DEVICES AND METHODS FOR FORMING MECHANICAL JOINTS

Abstract

A fastener device including mating hook-type and a complementary loop-type elements for releasable interengagement with each other includes at least first and second fastener tapes each having at least one surface having a plurality of such elements upstanding therefrom and defining a respective mating surface. When the elements are placed in face-to-face relation engagement of the elements takes place forming a unitary hook and loop structure resisting separation by forces substantially parallel to the interfacial plane of engagement. Auxiliary devices are provided to keep the unitary structure in a compressed state. The auxiliary devices are adapted to perform protective or compression functions. In the protective function the compressed state of the device is obtained as a result of compression of the hook and loop unitary structure. In the compression function additional compression of hook-type and loop-type elements by a special device is generated and said compression state is maintained.

Claims

1-22. (canceled)

23. A fastening device including hook and loop elements for releasably interlocking with each other, said fastening device comprising: at least first and second devises, each said device having at least one surface having a plurality of said elements extending outwardly therefrom and forming a respective mating surface; wherein when said elements are placed face-to-face and until said elements are engaged to form a single hook and loop integral structure resisting separation under action of separation forces directed parallel to a plane of contact between said elements; a compression device with movable members provided for holding said integral structure in compression during an entire operation of the fastening device in first and second states; wherein in the first state the movable members are superimposed before contacting said integral structure without compressing thereof, and in the second state the movable members of the auxiliary/compression device are superimposed before contacting the integral structure accompanied by subsequent compression thereof; and wherein the hook and loop elements are formed with free ends, in the first state the free ends of the hook and loop elements are held in engagement to protect the integral structure from separation; and in the second state the integral structure is compressed to increase the separation forces directed parallel to the plane of contact.

24. A method of operating a fastening device including hook and loop elements, the hook element comprises multiple hooks forming a part of a hook base and the loop element comprises multiple loops forming a part of a loop base, said hook and loop elements/bases configured for releasable interlocking with each other, the method comprising the steps of: providing first and second devices with each said device having at least one surface with a plurality of one of said hook or loop elements extending outwardly therefrom to form respective mating surfaces; placing the mating surfaces in face-to-face relation such that the hook and loop elements are positioned for engagement; squeezing the mating surfaces together to interlock the hook and loop elements and to form an integral hook and loop structure that resists separation under forces directed generally parallel to a plane of contact between the mating surfaces; providing a compression device having movable members configured to hold the integral structure in compression during operation of the fastening device in first and second operational states; in the first operational state, positioning the movable members of the compression device in a superimposed relationship before contacting the integral structure without compressing the integral structure, thereby holding free ends of the hook and loop elements in engagement to protect the integral structure from separation; in the second operational state, positioning the movable members of the compression device in a superimposed relationship before contacting the integral structure and subsequently compressing the integral structure, thereby increasing the separation forces directed generally parallel to the plane of contact; and deforming the hook elements in height during said compression.

25. The method of claim 24, further comprising the step of applying an external compression force to the interlocked hook and loop elements, whereby the hooks penetrate deeper into the loop base such that at a predetermined compression level is achieved, the hooks are positioned adjacent to the loop base, and further wherein continued compression produces elastic deformation of the hooks from an initial position (A) through intermediate positions (1, 2) to a compressed position (B), thereby reducing a hook base thickness (SHL.sub.2) below an initial hook height (H.sub.0).

26. The method of claim 25, wherein contact between the hooks and the loop bases occurs under a normal force (N.sub.1), and a further increase of the normal force to a value (N.sub.2) results in reduction of the hook height by an amount .

27. The method of claim 26, wherein a degree of an allowable compression of the hooks () is defined by the expression =[(H.sub.0SHL.sub.2)/(H.sub.0H*)]100%, where H.sub.0 represents the height of the hook in a free state and H* represents a limiting height of the hook under maximum compression.

28. The method of claim 24, further comprising a step of applying compression by an external compression device to interlock the hook and loop bases/elements, whereby the hooks penetrate deeper into the loop base until positioned adjacent to the loop base, and wherein continued compression of the hook and loop bases/elements produces elastic deformation of the hooks from an initial position through an intermediate positions to a compressed position, thereby reducing a hook base thickness (SHL.sub.2) below an initial hook height (H.sub.0); wherein contact between said hooks and loop bases/elements occurs under a normal force (N.sub.1), and a further increase of the normal force to a value (N.sub.2) reduces the hook height by an amount ; and wherein a degree of the allowable compression () is defined by the relationship =[(H.sub.0SHL.sub.2)/(H.sub.0H*)]100%, where H.sub.0 represents the height of the hook in a free state, H* represents the height of the hook under a maximum normal force (N*) corresponding to loss of stability, and SHL.sub.2 represents the current hook height under an applied normal force (N.sub.1<N<N*).

29. A method of operating a fastening device including hook and loop elements configured for releasable interlocking with each other, the method comprising the steps of: providing first and second elements, each said element having at least one surface with a plurality of one of said hook or loop elements extending outwardly therefrom to form respective mating surfaces; placing the mating surfaces in face-to-face relation such that the hook and loop elements are positioned for engagement; squeezing the mating surfaces together to interlock the hook and loop elements and to form an integral hook-and-loop structure that resists separation under forces directed generally parallel to a plane of contact between the mating surfaces; providing a compression device having movable members configured to hold the integral structure in compression during operation of the fastening device in first and second operational states; in the first operational state, positioning the movable members in a superimposed relationship before contacting the integral structure without compressing the integral structure, thereby holding free ends of the hook and loop elements in engagement to protect the integral structure from separation and causing the compression device to perform a protection function; in the second operational state, positioning the movable members in a superimposed relationship before contacting the integral structure and subsequently compressing the integral structure, thereby increasing the separation forces directed generally parallel to the plane of contact and causing the compression device to perform a compression function; applying compression by the compression device to the interlocked hook and loop elements such that the hooks and protrusions penetrate deeper into the loop layer until positioned adjacent to a base surface; wherein continuing compression produces an elastic deformation of the hooks from an initial position (A) through intermediate positions to a compressed position (B), thereby reducing an interlayer thickness (SHL.sub.2) below an initial hook height (H.sub.0); wherein contact between each hook and the base surface occurs under a normal force (N.sub.1), and a further increase of the normal force to a value (N.sub.2) reduces the hook height by an amount ; and wherein a degree of the allowable compression () of the hooks is defined by the relationship =[(H.sub.0SHL.sub.2)/(H.sub.0H*)]100%, where H.sub.0 represents the height of the hooks in a free state, H* represents the height of the hooks under a maximum normal force (N*) corresponding to loss of stability, and SHL.sub.2 represents the current hooks height under an applied normal force (N.sub.1<N<N*).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is a view showing a hook and related elements;

[0010] FIG. 2 is another view showing a hook and related elements;

[0011] FIG. 3 is a view showing a loop tape and related elements;

[0012] FIG. 4 is a side view showing the hook tape;

[0013] FIG. 5 is a view showing a technological hook;

[0014] FIG. 6 is a view showing a textile fastener, hook and loop fastener and an interlayer element:

[0015] FIGS. 7a, 7b, 7c, 7d, 7e, 7f, 7g and 7h are the views showing loading of hook and loop elements by external forces;

[0016] FIGS. 8a and 8b are the views showing a hook and loop unitary joint;

[0017] FIGS. 9a, 9b and 9c are the views showing deformation of the hook elements in straight (b) and reverse (c) directions;

[0018] FIG. 10 is a view showing compression the hook elements;

[0019] FIGS. 11a, 11b, 11c, 11d and 11e are the views showing deformation of hooks and a protrusion;

[0020] FIGS. 12a, 12b and 12c are the views showing tensile deformation of hook and loop fastener arrangement;

[0021] FIGS. 13a, 13b, 13c, 13d, 13e, 13f, 13g, 13 h and 13i are views showing compression devices for flat unitary joints;

[0022] FIGS. 14a and 14b are the views showing compression devices for the flat unitary connection exposed to transverse and longitudinal deformations;

[0023] FIGS. 15a, 15b, 15c, 15d, 15e, 15f, 15g and 15h are the views showing compression devices for cylindrical surfaces;

[0024] FIGS. 16a, 16b, 16c, 16d and 16e are the views showing half-rings and belts;

[0025] FIG. 17 is a view showing compression of the hook and loop arrangement;

[0026] FIGS. 18a, 18b, 18c, 18d, 18e, 18f, 18g, 18h and 18i are the views showing force members of compression devices for cylindrical surfaces;

[0027] FIGS. 19a, 19b, 19cl, 19c2, 19d, 19e and 19f are the views showing protection arrangement for flat surfaces;

[0028] FIGS. 20a, 20b, 20c, 20d, 20e, 20f and 20g are the views showing protection arrangement for cylindrical surfaces;

[0029] FIGS. 21a, 21b, 21c, 21d, 21e and 21f are the views showing elements of protection arrangement;

[0030] FIGS. 22a, 22b, 22c and 22d are the views showing fastening of the rod by means of buckles and a clamp;

[0031] FIGS. 23a, 23b, 23c, 23d and 23e are the views showing various types of protection arrangements for clamp connections;

[0032] FIGS. 24a, 24b, 24c, 24d1 and 24d2 are the views showing clamp stoppers;

[0033] FIGS. 25a and 25b are the views illustrating recommendations for the use of hook and loop;

[0034] FIG. 26 is a view showing unitary connection exposed to compression;

[0035] FIGS. 27a, 27b, 27c, 27d and 27e are the views showing a flat connection unit;

[0036] FIG. 28 is a view showing a flat connection unit consisting of four unitary arrangements.

[0037] FIGS. 29a, 29b, 29c and 29d are the views showing a handle toggle clamp;

[0038] FIGS. 30a and 30b are the views showing installation of a handle toggle clamp on a cart and a wall;

[0039] FIGS. 31a. 31b and 31c are the views showing a compressor holder;

[0040] FIGS. 32a, 32b and 32c are the view showing a stopper of a compression device;

[0041] FIGS. 33a, 33b, 33c and 33d are the views showing embodiments for a bar connection;

[0042] FIGS. 34a, 34b, 34c, 34d and 34e are the views illustrating a flange coupling;

[0043] FIGS. 35a and 35b are the views illustrating an end coupling;

[0044] FIG. 36 is a view showing an embodiment of an end coupling;

[0045] FIGS. 37a, 37b, 37c and 37d are the views showing fastening the rod by means of buckles and a clamp;

[0046] FIGS. 38a, 38b and 38c are the views showing fastening the rod by a clamp to the parts;

[0047] FIGS. 39a and 39b are the views showing securing the rod with a clamp;

[0048] FIGS. 40a, 40b and 40c are the views also showing securing the rod with a clamp;

[0049] FIGS. 41a, 41b and 41c are the views also showing securing the rod with a clamp;

[0050] FIG. 42 is a view showing fastening of the rods by a clamp having one cross-sectional profiles:

[0051] FIG. 43 is a view showing fastening of the rods by a clamp having another cross-sectional profile;

[0052] FIG. 44 is a view showing fastening of the rods by a clamp having a further cross-sectional profile:

[0053] FIG. 45 is a view showing an installation and its parts for compression of a hook and loop fasteners;

[0054] FIG. 46 is a chart illustrating thickness of hook and loop fastener and its parts;

[0055] FIG. 47 is a view showing an installation for stretching a hook and loop unitary connections;

[0056] FIG. 48 is a chart illustrating elongations of a unitary hook and loop fastener connection from applied tensile force;

[0057] FIG. 49 is a view showing a flat unit;

[0058] FIGS. 50a, 50b and 50c are the views showing a test installation for flange couplings;

[0059] FIG. 51 is a chart illustrating dependences of an angle of relative rotation of the flange coupling from the applied torque;

[0060] FIG. 52 is a view showing deformations of the hook tape and the loop tape provided on shafts;

[0061] FIGS. 53a, 53b and 53c are the views showing an installation for testing of end couplings;

[0062] FIG. 54 is a chart illustrating dependence of the angle of relative rotation of the end coupling from the applied torque; and

[0063] FIGS. 55a and 55b are the views showing an end coupling.

INITIAL DISCUSSION OF THE DISCLOSED TECHNOLOGY

[0064] For the purposes of disclosing an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. However, the illustrated embodiments are merely exemplary and many additional embodiments of this invention are possible. For example, this invention is shown in use with portable electronic devices; however, this invention is not intended to be limited to portable electronic devices. It is understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the illustrated devices, and such further application of the principles of the invention as illustrated herein are contemplated as would normally occur to one skilled in the art to which the invention relates.

[0065] Unless otherwise indicated, the drawings are intended to be read (e.g., arrangement of parts, proportion, degree, etc.) together with the specification, and are to be considered a portion of the entire written description of this invention. As used in the following description, the terms horizontal, vertical, left, right, up and down, as well as adjectival and adverbial derivatives thereof (e.g., horizontally, rightwardly, upwardly, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms inwardly and outwardly generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate.

[0066] Hook and loop connecting arrangement typically consist of two parts in the form of flexible textile tapes or elements such as a hook element and a loop element. The hook tape element comprises multiple hooks 2, 8 forming a part of a base 1 (FIG. 1, 2) and the loop tape element comprises multiple loops 11 (FIG. 3). The thickness of the hooks is typically much greater than the thickness of the loops, and the number of loops is many times greater than the number of books per unit area.

[0067] Hooks 2 and 8 on textile tapes are arranged in rows 15, 16 across the woven warp 1 (FIG. 4). They are obtained by cutting technological loops 17 (FIG. 5) with the formation of a gap 4 (FIGS. 1, 2). One row of technological loops along its row has cuts on one side of an axis of symmetry 5 of the loop (FIGS. 1, 4, row 15), and the next row after it is on the other side of its axis of symmetry 5 of the loop (FIGS. 2, 4; row 16) The result is multidirectional hooks 2 and 8, alternating through a row. They are called in the application as a straight line of hooks (row 15) and reverse line of hooks (row 16). All hooks in rows 15, 16 (FIG. 4) are approximately perpendicular to the row line direction. The remaining part 3 after cutting the technological loop is called a protrusion (FIG. 1, 2).

[0068] The loops 11 on the loop tape (FIG. 3) are randomly positioned on the base 10 without a visible orientation (in FIG. 3 they are shown at the time of manufacture of the tape). Both parts of the arrangement can be made from a variety of resilient fabrics. For example, they can be made of nylon. The front sides of textile tapes are the sides of the hooks 6 and loops 12, and the reverse side is the sides 7 and 13. The two parts of book and loop connecting arrangement are connected to each other by overlaying with the front sides, followed by short-term compression by hands of a person, for example. During the compression, the hooks penetrate deep into the loop layer (FIG. 6).

[0069] Hook and loop textile tapes and their connection are denoted in the application as follows: [0070] connection of textile tapeshook and loop arrangement, [0071] hook textile tapehook tape, [0072] loop textile tapeloop tape.

[0073] The contact zone of the hook and loop fastener connecting arrangement is a three-dimensional structure, in which rows of hooks protruding to a certain height from the base 1 are embedded in a layer of thin loops randomly arranged on the base 10 (FIG. 6). For the purposes of the application, it is called a contact zone arranged between bases 1 and 10, and interlayer 18 (FIG. 6).

[0074] To disconnect the book and loop fastener connected parts, it is needed to pull the edges of the hook and loop tapes by hands in a direction away from each other, regardless of the orientation of the hooks in the rows (FIG. 7b, c, d).

[0075] There are several methods of obtaining hooks and loops for hook and loop connecting operation in specific conditions. For example, according to one of the methods, hooks of different directions are made on a common leg without a protrusion. In another way, nonwoven materials are used as the loop in medical products. But in all cases, the original idea of the connecting arrangement is retained, wherein the hooks and the loops engage each other.

[0076] Below you will find discussion of various hook and loop connecting arrangements. One of the most common application is in use of this connecting arrangement in sewing, shoe and other industries, construction, as well as in medical devices. In the drawings hooks are shown to be slightly larger, so they can more clearly illustrate the features of the invention. Although the present invention is disclosed based on application of two textile tapes containing hooks and loops, principles of the invention are applicable to a substantial variety of hook and loop connecting arrangements.

[0077] The forces can be applied in 3 different directions to connected to each other by superimposition hook and loop elements (FIG. 7): [0078] A. Forces are applied perpendicular to the contact area of the hook and loop elements: [0079] Forces are applied to the entire contact area at the same time (FIG. 7a, force P); for this reason the hook and loop elements should be attached to rigid parts; [0080] Forces are applied from one side of the joint simultaneously to both edges of the hook and loop elements during the step of delamination (FIG. 7b, force P); [0081] Forces are applied from one side of the connection to the edge of either one hook and loop element during delamination, if the second hook and loop part is attached to a stationary rigid part with a flat or cylindrical surface (FIG. 7c, force P); [0082] If the hook and loop connecting arrangement is attached to a cylindrical surface, such as a shaft, the ends of the lower element of a connecting arrangement are overlapped by the upper element of the connecting arrangement; and only the ends of the upper element are accessible. In this case, the disconnection is made by applying force to one of the ends of the upper element of the hook and loop connecting arrangement (FIG. 7d, force P).

[0083] B. Referring now to the situation, wherein both parts of hook and loop fastener (for example, self-adhesive hook and loop arrangement) are fixed on the flat or cylindrical surfaces of two rigid parts. The parts are superimposed on each other and squeezed by hands. In this situation, the ends of the hook and loop elements are not accessible. This situation occurs when disassembling hook and loop connections and requires special recommendations. Consider two options when a force R is applied to the parts, and when a torque M is created by a force S applied at some distance from the hook and loop fastener joint (FIGS. 7e and 7f).

[0084] In the option of creating a torque by force S in a flat joint (FIG. 7e), the force S is applied, for example downward, and due to thickness related the thickness of the hook and loop fastener layer and the adhesive layer in the case of a self-adhesive structure, micro-deformations of the hooks and deformation of the adhesive layer occur. As a result of this, the part to which the force is applied rotates approximately around the point H, and distributed stresses arise along the interlayer with the resulting force T on the arm k. In this case, the torque is calculated as follows: M=kT.

[0085] The greatest stresses in the hook element occur in the region of maximum distributed loads (left side in FIG. 7e). If you increase the value of the torque M, then from a certain value, the loops will disengage a limited number of hooks located in maximum distributed loads. This will cause subsequent delamination of the entire connecting arrangement. In this case, the disconnection of the hook and loop joint occurs not by acting directly on the ends of both pieces, but by acting on the ends of the pieces through the joint pieces.

[0086] When the direction of action of the force S changes, the part rotates due to micro-displacements in the interlayer approximately around the point G, and the greatest stresses in the joint arise in the region along the line passing through the point H. A similar situation with the distribution of loads along the line of contact occurs when the force R is applied to the right side of the joint.

[0087] C. Referring now to the embodiment of FIG. 7f wherein the hook and loop elements are attached to the cylindrical surfaces of two rigid pieces. The parts are loaded in the same way as in the flat joint.

[0088] Referring now to FIGS. 7g and 7h, wherein forces are applied tangentially along the direction of the foundations/bases 1 and 10 (FIG. 7g, h, force P.sub.1), rows 15, 16 of the hooks are situated perpendicular to the direction of action of the force P.sub.1;

[0089] Forces are applied tangentially to the bases 1 and 10 of hook and loop arrangement (FIG. 7g,h), but rows 15, 16 of the hooks are oriented at an angle to the direction of the acting force P.sub.2; the angle can vary between 90 and 0 degrees (FIG. 7h).

[0090] Hook and loop fasteners react differently to the applied forces. The smallest force is required when peeling one part of the hook and loop arrangement from another. Such peeling is carried out by the pulling force directed away from the connection and applied to the edges of hook and loop arrangement (FIG. 7b, c, d). In this case, the arising exfoliation force can be applied by fingers of a person's hands. This is because it acts in the separation zone on a small number of hooks and loops at each time from initial separation until complete separation.

[0091] In any hook and loop arrangement/joint there is an edge that can be pulled, and the entire connection is peeled off to disassemble the connection. This is an advantage of joints using hook and loop arrangements. However, in some instances this is also a disadvantage that must be overcome in the present invention when it comes to assure safety and reliability of the connection under load.

[0092] Maximum hook and loop connection bond strength occurs when the force is applied tangentially along the hook elements (FIG. 7g, h, force P.sub.1). When the hooks are oriented at an angle to the direction of the force, the transmitted tangential force decreases.

[0093] The use of hook and loop arrangement to transmit tangential forces is limited in size by the ability to withstand these forces by the strength characteristics of the materials of hooks and loops, warp 1 and 10, and the operating conditions of the joint. The present invention encompasses devices that receive and transmit tangential (tensile) forces along the foundations/bases of hook and loop elements.

[0094] Referring now to FIG. 6, wherein the layer 18 when compressed through the supports 1 and 10 with a normal force N uniformly distributed over the entire contact area. Situation should be also considered when after the compression, a tensile force P.sub.1 is applied to the bases, which force is provided in the joint in the form of tangential (shear) forces along the bases (FIG. 9).

[0095] Option 1. The segment of hook tape 19 and the segment of loop tape 20 are connected along the length L, which is a part of their length, and briefly squeeze segments by the fingers developing force N.sub.0, and then remove the fingers (FIG. 8a). To the right and left of the contact zone of the hook and loop fastener parts there will be two free sections of the segmentscalled tails. There are sections of hook and loop fastener parts in the contact zone of length Lcalled wings. As a result, a hook and loop fastener 21 sample is formed consisting of hook and loop fastener parts superimposed on each other, compressed wings and two free tails on the sides. This hook and loop fastener 21 sample is called a unitary structure/connection.

[0096] In certain instances to produce hook and loop arrangement rolling of the superimposed hook and loop fastener elements/parts between two rollers is used. In this action the arrangement is compressed with the calibrated force N simulating hand compression (FIG. 8b); with one of the rollers being the leading roller.

[0097] During the superimposition and compression of the hook and loop elements, the top of the books and protrusions 3 (FIG. 1) penetrate in the layer of loops 11 in the base 10 (FIG. 6). The top of the hooks and protrusions inside the loop layer are practically not deformed. Part of the loops 11 in the amount of 1 or more (FIG. 6) penetrate through the gap 4 into the interior of the hook, into the area of gripping the loops by the hook and remain in this zone after compression by hand.

External compressive force after compression ends is N=0.

[0098] Denote the height of the hooks in the contact zone H.sub.0, and the thickness of the layer in the contact zone (interlayer thickness) S.sub.HL1; H.sub.0<S.sub.HL1 (FIG. 6).

After that, the tensile force P.sub.1 is applied to hook and loop fastener (FIG. 9).

[0099] From the moment the tensile force P.sub.1 is applied and as it increases, the relative displacement of the bases 1 and 10 of the hook and loop fastener parts increases due to the deformation of the hooks by the loops and the loops themselves that have penetrated the grip zone. Hooks 2 (FIG. 1) are deformed and oriented against the direction of the acting force P.sub.1. In FIG. 9b the simulation is illustrated of the deformation of one hook 2 with one loop 11. The loop is shown as non-stretching. Practically, it is easily deformed, and its length depends on the resistance of the hook to bending and the ability to be pulled out of the base 10).

[0100] It should be noted that not all loops simultaneously come into rigid contact with the hooks. Therefore, at each moment of time, as the bases 1 and 10 move, the growing force P.sub.1 is accepted by the loops that are in rigid contact with the hooks at different stages of their elastic deformation. Reverse hooks are also used (FIG. 9c).

[0101] The protrusions 3 are practically not captured by the loops. In addition, the book tape and loop tape are deformed to different degrees; the hook tape base is harder in tension than the loop tape base.

[0102] Depending on how many loops and in what particular elastic state loops are on the hook, the deformation of the hooks themselves and the stretching of the loops in the layer will be different. As a result, under the action of the force P.sub.1, the bases begin to move relative to each other, and this movement increases as the force P.sub.1 increases.

[0103] At the beginning there is an elastic movement of the bases. However, when a certain value of the force P.sub.1 and relative movement of the bases are reached, the loops disengage the books in the zone of their contact in the bases (FIG. 9a, arrow B). This leads to the decrease in the length of the contact zone and to the increase in tensile forces in the loops. This also leads to the increase in the deformation of the hooks, and to the involvement of more loops in hard contact with them.

[0104] The connection begins to lengthen from the initial position 0 through the positions 1, 2, 3. There is also a relative movement of the basics 1 and 10 hook and loop (FIG. 9b, c).

[0105] With the increase in tensile (tangential) forces, the ultimate deformation of the hooks and loops in the layer is achieved. Also, a gradual straightening of the hooks in contact with the loops 11 begins. Since they are oriented in the direction of action of the force P.sub.1, the loops disengage from the hooks. Hook and loop parts slide relative to each other, and then the entire connection breaks and parts of the hook and loop arrangement disengage.

[0106] Option 1, the interaction of the hook and loop parts in the contact zone when applying to their bases 1 and 10 forces of various orientations (FIG. 6) can be considered as the interaction of two bases through a layer having specific adhesive properties. They appear in maintaining the adhesion of the hooks to the loops upon applying the hook and loop fastener parts to each other and removing their compression force.

[0107] Option 2. If Hook and loop arrangement is compressed by hands for a short time, while with the compression to be continued from outside, for example, by using a special compression device, then the hooks and protrusions begin to penetrate deeper into the loop layer. At certain point, the hooks are positioned at the base 10. FIG. 10 shows deformation of one hook from the moment of its contact with the base 10. Upon further compression by the increasing force N, clastic compression forces occur in the hooks 2. The hooks are deformed sequentially from the initial position A through positions 1, 2 to, for example, position B. As a result, the thickness of the interlayer S.sub.HL2<H.sub.0 is achieved.

[0108] Two positions of the hook from the moment of contact with the base 10 (position A) to the compressed state in position B (FIG. 10) are being considered.

[0109] To achieve a contact between the hook and the base 10, a normal force N.sub.1 is required. Upon further increase in force to the value N.sub.2, the hook height was decreased by .sub.B.

[0110] The deformation of the hook in height can be estimated by the value of its relative compressionthe degree of compression of the hook (compression means the vertical movement of the base 10):

[00001]$\begin{array}{cc}=\left[\left(H_0-S_{\mathrm{HL}2}\right)/\left(H_0-H^{*}\right)\right]/100\%.& \left(A\right)\end{array}$ [0111] where H.sub.0 is the height of the hook in the free state; [0112] H* is the height of the hook pressed as far as possible to the base 1 with the loss of stability by the normal force N*; [0113] S.sub.HL2 is the current hook height under the action of the force N, where N.sub.1

[0115] If in a compressed state, for example, in position B (FIG. 10, 11b), a tensile force P.sub.1 is applied to the base of hook and loop arrangement (FIG. 11c), the following factor will begin to influence the relative displacement of the base (as compared to the hook deformations in FIG. 9b) The increased bending stiffness of the hook will occur when loading the hook with loop 11 on the base 10 takes place. This is because if in option 1 (FIG. 9b), the hook was loaded by loop 11 as a cantilever beam (FIG. 11a). Now in option 2 there is an additional support at the contact point at the top of the hook with the base 10 (FIG. 11b, point A). Then the hook begins to operate as a two-support beam. This occurs due to the emerging frictional force F.sub.f between the top of the hook and the base 10 at point A. This increases the bending stiffness of the hook and, therefore, increases the maximum force in which the loops 11 come off the hook (FIG. 11c, after position 5).

[0116] If the interlayer is compressed by the normal force N.sub.3>N.sub.2 to position C (FIG. 10), then in this position the base 10 touches the protrusion 3 and begins to compress it. When a tensile force P.sub.1 is applied, some loops 11 are in the firm contact with the protrusions 3 from rows 15 and 16 (FIGS. 1, 4, 11e). In this case, the protrusion operates under the action of the loop 11 as a two-support beam. This indicates that with a certain degree of compression of the hooks, the protrusions 3 are also included in the operation.

[0117] As in the option 1, with an increase in tensile (tangential) forces, the ultimate deformation of the hooks and loops between the bases is achieved. Then the gradual overcoming of the friction force between the hook and the base 10 at points A begins. As the hooks bend and move along the base 10, their elastic force of compression decreases from contact with the base 10. The hooks are placed into the cantilever position (after position 3 of the loop. FIG. 11c).

[0118] In the interlayer 18, simultaneously with the compression of the hooks 2 (direct orientation from row 15, FIG. 4), the hooks 8 (reverse direction from row 16, FIG. 4, 11d) are compressed. As a result, each considered hook and loop elements in the interlayer contributes in different ways their part in the magnitude of the transmitted shear/longitudinal forces.

[0119] With continued increase in tensile force in the layer, all hooks are straightened, they are oriented in the direction of action of the force P.sub.1; the sliding of hook and loop parts relative to each other begins, and then the entire joint falls apart since parts with hook and loop come out of contact.

[0120] Also, as in Option 1, the relative movement of the bases 1 and 10 begin from the moment of application of the force P.sub.1 to the connection. It follows from the above that when the hooks are compressed by force N.sub.2 (N.sub.3), the maximum value of the tangential force transmitted by hook and loop joint increases, which is increases tensile force P.sub.1.

[0121] In the conducted experiments this is confirmed by measurements taken at the hook and loop joint. Further, in the abrasive industry, angle grinders are known in which a circular sandpaper disc is attached through a hook and loop joint to the drive disk of the machine. During operation, the emery wheel is pressed by the operator at an angle to the work surface, while in the contact zone hook and loop joint is compressed to transfer the working force of grinding. The emery wheel itself (it has loops), if necessary, is easily separated from the disc with hooks by peeling off with fingers of an operator.

[0122] In the discussion of the option 1, it was noted that the contact zone of the hook and loop parts (interlayer) can be considered as having specific adhesive properties. In the case of the option 2 with compression of hook and loop parts from outside, it can be considered that the introduction of compression improved the adhesive properties of the interlayer. In this sense, the hook and loop joint can be considered as an adhesive joint with specific glue properties, and which also has the possibility of easily losing these properties when the joint is taken apart.

[0123] Now we examine two compression options for hook and loop joint. In the initial option, a constant compressive force N is absent, and in the following optioncompression of the layer with the deformation of the hooks with a constant force N is provided. By changing the compression ratio of hook and loop joint with a normal force N from outside, the maximum value of the transmitted tangential (tensile) forces can be changed.

[0124] The value of the tangential (tensile) force transmitted by hook and loop joint, in addition to the degree of compression of the hooks , directly depends on the number of hooks that are engaged, i.e., depends on the size of the area of the hook and loop contact zone. The value of hook and loop joint compressive normal force N also depends on the number of deformable hooks.

[0125] After removal of the compressive force and separation of the hook and loop parts, for example, as a result of disassembly or breaking of the connection, due to the elasticity of the materials of the hooks and loops, their relaxationreturn to the initial state before the assembly of the joint. This takes some time. The relaxation is especially intense at the first time, when it often takes minutes, and after a while the hooks and loops adapt an approximately original shape/condition before the compression.

[0126] But return of the hooks and loops to the initial state, before being superimposed on each other and the compression being applied, may not occur completely. This depends on the physic-mechanical properties of the Hook and loop fabrication material, the magnitude of compression and the time spent in the compressed state. This also depends on the operating temperature of the connection parts and the ambient temperature, time expired after unloading and disassembling hook and loop joint, and other reasons.

[0127] Hook and loop joint typically is not designed to operate in an extreme mode, i.e., in the mode of a possible joint breaks. In this mode, residual deformations of hooks with their straightening and breaking of loops in the hook and loop-loop occur and accumulate upon repeated breaks in the joint. This leads to the fact that subsequent breaks of the connection occur at ever smaller loads. Extreme loads should be measured only to determine the margin of safety of the joint and does not represent a workload.

[0128] It should also be noted that after unloading and disconnecting the hook and loop joint, it takes some time for the relaxation of the hooks and loops to occur. To accelerate relaxation, it is possible to warm hook and loop-hook with warm air, without exceeding the permissible temperature, and additional time for relaxation in natural conditions, as well as by other means.

[0129] The complexity of the study of the processes of interaction of hook and loop parts and elements in the contact zone, given their small size and the large number of hooks and loops at different stages of the stress state in the contact zone, requires use of empirical methods for analyzing Hook and loop joints operation.

[0130] To implement the present invention in the hook and loop joints, two types of auxiliary devices and elements are used. For the purpose of the application the first type is called compression, and the second type is called protection devices. Such devices perform different functions depending on the design, purpose, characteristics of hook and loop joints and their working conditions. These auxiliary devices provide hook and loop joints new properties.

[0131] Hook and loop compression function is performed by special auxiliary compressing devices. It is designed to compress the hook and loop joint and keep it in the compressed state during operation of the joint. The compressing device consists of hook and loop-compressing parts with flat or cylindrical surfaces and force applying elements.

[0132] There are situations when the required value of the force transmitted by the connection is ensured by applying the hook and loop elements to each other and accompanied by a short-term compression by the hands of a user, without using additional external compression. In this case, the main issues are safety and reliability of the join under load permissible for this connection. For example, when one or both parts of the hook and loop joint are flexible, and at the same time the hook and loop joint transmits some force, the hook and loop joint is easily separated by fingers pulling on free end of the flexible parts away from the hook and loop joint. The connection or joint is dismantled under the load.

[0133] It is not advisable to keep the free and unprotected ends of the hook and loop joint, which a user pulls to disassemble and take the connection out of working condition. For example, when torque is transmitted by a rotary coupling or sleeve coupling in an open area or in a liquid medium, an incoming flow of air or liquid may peel off the joint. Negative application of centrifugal forces is also possible.

[0134] The above condition is especially unacceptable if the joint or connection is under a load. Therefore, the free ends must be protected from the possibility of accidental external influences, including the human factor. In addition, disconnection of the hook and loop joint during operation can occur not only due to exposure to the fingers of a person's hand, but also due to differences in the physic-mechanical properties of the hook and loop elements. This leads to varying degrees of elongation under current loads. This is because the loop base extends by a larger degree than the hook base. In addition, when the hook and loop fastener is stretched, due to the thickness and stiffness of the hook tape compared to the loop tape in area A (FIG. 12a), delamination occurs in the direction of the arrow B due to the peel force Q (FIG. 12b), which increases with repeated application of tensile load P.

[0135] In view of the foregoing, in the present invention in the above-discussed joints to ensure their safety and reliability, another type of auxiliary devices or protection devices is used.

[0136] Protection devices is a complex combination of various devices (including hook and loop joints) and elements for keeping hook and loop elements in a state that was briefly compressed by hands of a user during initial operation of the connection. These devices and components should complicate access to the free ends of the hook and loop wings. Protective function should include at least one additional action of the operator. This occurs after a purposeful execution of action in which free, unprotected ends of the Hook and loop parts are exposed. Then, the hook and loop parts themselves can then be separated by the fingers of a hand of a user. Protective devices should also prevent progression of the already initiated detachment of Hook and loop parts due to their physical and mechanical properties.

[0137] Additional actions of an operator may include, for example, a preliminary release of a predetermined one or multiple joints before the main action takes place. The main action might include delamination of the connection; or removing a thin adhesive tape placed on the edge of the wing of the hook and loop specimen or pulling the end of the clamp out of the buckle. Preliminary release of the main hook and loop joint by fingers of a user should be a meaningful action, if necessary, with a safety net, and should not lead to emergency situations of breaking the connection under load. The degree of complexity of the protection device is determined by the operating conditions of the connection and the requirements of reliability.

[0138] Protection devices perform the same function as the fuse in the revolver, protecting against accidental fall, blow, etc. that is, from any unintended and not intended use. Protection devices are used only in the embodiments operating under the initial option, wherein hook and loop joint is compressed by hand. In the joints compressed by the compressing arrangements, there is no need in protection devices. The compressing arrangement discussed below can be used as protection devices which are installed with minimal compression of the hook and loop joint.

[0139] An alternate situation can be also considered. If a self-adhesive hook element or Hook and the loop element is attached to a surface with a large curvature, then over time, in the free, disassembled state of the joint, detachment of their cut ends is observed. This is especially noticeable on the hard parts of the hook joint. Therefore, the softest part, namely the loop, should be glued to cylindrical surfaces. However, the cylindrical surface also needs own protection arrangement.

1. Compression

[0140] Compression devices must be designed to compress the entire hook and loop fastener joint evenly and to remain in this state throughout the entire operation.

A. Compression Arrangement for Flat Surfaces.

[0141] Flat surfaces are most suitable for the compressing action. For this purpose, a compact compressing arrangement is obtained, which provides evenly compressed hook and loop joint between two plates to the desired size.

[0142] In FIGS. 13a, 13b, 13c. 13d, 13e, 13f, 13g, 13h and 13i possible designs of such compression arrangements are shown, wherein hook and loop elements are compressed between the flat surfaces of two parts 22 and 23. Compression is carried out, for example, by screw connections 25, 26, a flat spring 27, a clamp 28, a weight 29, and latches 30.

[0143] The compression ratio in the compression devices is set to accommodate the structural size H of the window. This can be accomplished by installation of thin gaskets 24 or adjusting screws 31. The width of the window B* in the compressing arrangement allows free installation of the connected hook and loop parts.

[0144] In these compression arrangements, it is possible to provide the same hook and loop compression along the entire joint L. It is also possible to create another compression in separate sections. For example, it is possible to compensate for the change in the thickness of the hook and loop sample due to the presence of an attached element at the compression site, which caused, for example, by local thickening, not related hook and loop compression. Then, to obtain the same hook and loop compression, above this element the compressor plates are removed to achieve the thickness of the element to the size H.sub.1 (FIG. 13b).

[0145] Hook and loop specimens in compression arrangement can be compressed not only between flat surfaces, but also between cylindrical surfaces with a guide 32 located along the hook and loop specimen (FIG. 14a) or across the same (FIG. 14b, c).

[0146] Let us denote the thickness of all parts of the sample assembly in the free state (before the installation of the compressor) H.sub.0, and their thickness in the state of the compressor compressed by H. We introduce the concept of compression ratio of the assembly:

[00002]$\begin{array}{cc}{}_1=\left[\left(H_0-H\right)/H_0\right]100\%.& \left(B\right)\end{array}$

[0147] By setting a different degree of compression, we simulate the action of an external compressive force N, deforming the assembly to a given thickness N. By the compression devices of this type, it is easy to set and control the compression ratio, since it is only set by the height H of the compressor window.

[0148] The compression ratio of the assembly includes the thickness stiffness of the parts and their elements to which the hook and loop fastener elements are attached. The force N compressing the parts 22 and 23 (FIG. 13) depends on the area of the hook and loop contact zone and the compression ratio of the assembly.

B. Compression Device for Cylindrical Surfaces.

[0149] The clamp must follow the shape of the surface on which the hook and loop fastener is located in order to act on virtually every hook and deform it to the required degree. In FIGS. 15a, 15b, 15c, 15d, 15e, 15f, 15g and 15h a process is illustrated for assembly of a joint that can be used to connect shafts and extend rods. Self-adhesive loop tapes 35 and 36 are attached to the ends of coaxial shafts 33 and 34 of the same diameter. A hook tape 37 linear piece is applied over them (FIG. 15b, c).

[0150] The compression arrangements are, for example, three pads 38, which, when assembled, without gaps at the joints, form an inner diameter D.sub.2=D.sub.12, where is the required hook and loop fastener compression (FIG. 15b, d).

[0151] Pads 38 are mounted on Hook Tape 37 and pulled together, for example, by clamps 40 to reach contacts at the joints (FIG. 15d, g). The overlays must be rigid enough to provide even book and loop fastener compression over the entire length of the joint.

[0152] The illustrated connection provides the required compression of hook and loop arrangement.

[0153] If the self-adhesive hook and loop type arrangement is used as the line segment of the hook-type and loop-type arrangement 37, the arrangement 37 is cut into three pieces and each piece is attached to the overlays 38 (FIG. 15e).

[0154] The connection of FIG. 15g is a sleeve coupling, in which book and loop elements 35, 36, 37, pads 38 and tightening collars 40 act as a sleeve. This sleeve is simultaneously the driving and driven elements of the entire coupling, i.e., torque from one shaft to another, as well as tensile forces are transmitted jointly by hook and loop-hook element 37 and overlays 38. When torque is transmitted in the area above the shaft junction into hook-type and loop-type arrangement 37, shear stresses arise, which manifests itself in some angular deformation of the shafts.

[0155] In the case of installation over each end of the shaft 33 and 34 of a separate compressing arrangement made of strips 39 and clamps 40 (FIG. 15f, h), it becomes possible to compensate by connecting small misalignments and misalignment of the shafts due to deformation of hook-type and loop type arrangement 37. Torque transmission occurs only through hook and loop type arrangement 37. The connection operates as a sleeve coupling and can be used as a flange coupling in which the flanges are connected to each other through a book and loop piece (FIG. 34).

[0156] Instead of overlays 38 and 39, covering hook and loop fastener without a gap at the joints, it is possible to use half rings 43 with a diameter D.sub.1>D.sub.3>D.sub.2, having a gap m between the half rings in the compressed state of the joint (FIG. 16a). The joint 41 of the ends of the hook tape 37 should be covered with a half ring. In the case of self-adhesive hook tape 37, it is glued to half rings 43 (FIG. 16b, c). FIGS. 16a, 16b, 16c, 16d and 16e are the views showing half-rings and belts.

[0157] A corrugated belt 44 (FIG. 16d) can be used as a compression member. It is applied to both ends of shafts 35 and 36 and is pulled together by the force elements of the compressing arrangement.

[0158] The shafts 33 and 34 can have different diameters, in this case they can be connected by overlapping each other (FIG. 15e): the end of the shaft 33 is made, for example, in the form of a half pipe. On its inner surface self-adhesive hook tape 37 is fixed, and a piece of loop tape 35 is attached or glued to the end of shaft 34.

[0159] In some cases, it is possible not to use overlays and tighten the hook and loop assembly directly with at least one clamp 45 disposed over each part of the hook and loop fastener 35 and 36 (FIG. 17). In this case, the clamps cause local compression of the hooks. To increase the efficiency of the transfer of forces by the joint/connection, the width and number of clamps can be increased.

[0160] In the case of, for example, round parts with a radius R, when the clamp compresses the hook and loop fastener around the entire perimeter, the circumference thereof decreases.

[0161] If the length of the circle perimeter in the free state is L=2R, then if necessary, compress hook and loop arrangement, for example, by , the length of the circle perimeter with a radius (R) will be

[00003]$\begin{array}{cc}{L}_1=2\left(R-\right)=2R-6.3.& \left(C\right)\end{array}$

[0162] For example, to squeeze the hook and loop fastener 0.5 mm, the clamp (Screw clamp FIG. 18) needs to be tightened by about 3 mm. Knowing the required amount of compression Hook & Loop, the diameter D.sub.2 is determined. For the case shown in FIG. 17, to this diameter according to template 54 (FIG. 18) we adjust the clamp, for example, Screw clamp 52 (FIG. 18) and mark it in the required position.

[0163] FIGS. 18a, 18b, 18c, 18d, 18e, 18f, 18g, 18h and 18i are the views showing force members of compression devices for cylindrical surfaces that can be used as strength members of a cylindrical surface compressor. Other options are possible.

[0164] Cable tie guns can be used to ease the screed of cable tie and releasable cable tie. Cable Tie itself has to be cut when dismantling the connection, so they should be considered as consumable goods.

[0165] By analogy with the calculations of machine parts, we introduce the parameter of safety factor for hook and loop fastener compression:

[00004]$\begin{array}{cc}n=\left[\right]/,& \left(D\right)\end{array}$ [0166] where is the working compression of Hook & Loop, [0167] []allowable hook and loop fastener compression.

[0168] The safety factor for compression should take into account: [0169] the ability of hook and loop to recover (relax) after unloading and disassembling the connection. [0170] operating conditions of the compound: temperature, aggressiveness of the environment, etc. [0171] the quality and accuracy of the assembly of the connection of parts with hook and loop and the placement of a compressor on them.

[0172] Determining the safety factor requires testing specific compounds with hook and loop arrangement under actual operating conditions.

[0173] The hook and loop compression value can be set depending on the application conditions ranging from a conditional zero (when hook and loop arrangement is compressed only with the fingers of human hand) to the maximum value *, when the hook-type and loop-type tapes are compressed to approximately the thicknesses of the bases of hook-type and loop-type elements. Such compression unacceptable in working condition. In actual compression, allowable compression [] and safety factor must be taken into account.

[0174] Depending on the tasks being solved and the magnitude of the force transmitted by hook and loop arrangement, their compression may vary. It is assumed that in each case, a compressor for a constant compression value is used. However, there may be cases when this value may vary (be adjusted) depending on the operating conditions of the joint and the design of the compressing arrangement.

[0175] With multiple assemblies, loads and disassembly of the joint, damage to the hook and loop parts occurs, these damages are accumulated and at a certain point their influence becomes noticeable. In this regard, perhaps the concept of the allowable number of assembly-disassembly cycles of the joint, as well as the service life of hook and loop arrangement, based on the service life of the materials it is made of, should be introduced.

[0176] Hook and loop joints have the peculiarity that they are begins to lengthen from the moment tangential (tensile) forces are applied to the respective parts. For example, in hook and loop joints with a flat surface gripper (FIGS. 12a, 13), as increasing shear forces are applied to the hook and loop pieces, they are displaced relative to each other and then disengaged when one of the hook and loop pieces is pulled out of the gripper.

[0177] Elongation occurs mainly due to the elastic lengthening of the loops, their pulling out of the base, bending and deformation of the hooks, and with a certain amount of effortthe loops come off the hooks, in which loop breaks and damage to the books are possible.

[0178] The elongation range of the joint should be limited to its initial section, where the elastic properties of Hook and loop are realized, and which limits the amount of transmitted force. To do this, the parameter permissible elongation of the hook and loop connection [l] should be entered.

[0179] In connections such as sleeve and flange couplings with a compressor (FIG. 15h), one end of the shaft, when an increasing torque is applied to it, can rotate relative to the fixed second shaft by an unlimited angle with inevitable damage to the hook and loop parts. Torque transmitted through hook and loop increases in magnitude from the beginning of its application, reaches a maximum and then begins to decrease.

[0180] Torque is transferred from one shaft to the other through the hook section located above the shaft gap. Shear deformations are observed in this area.

[0181] Let's assume that there is no gap between the shafts. We are interested in the initial section of the increase in torque at a small relative rotation of the shafts .

[0182] If hook and loop strip is cut around the circumference in the area of maximum shear deformations with the middle of the strip above the ends of the shafts and unfold it, then in this strip the rows of hooks 15 and 16 (FIG. 4) between its lateral edges will have a shift towards the action of the torque due to for turning one shaft relative to the other (FIG. 34b, c) by the value 1. This shift is caused by the relative rotation of the shafts at an angle;

[00005]$\begin{array}{cc}k/R,& \left(E\right)\end{array}$

where the angle in radians, R is the radius of the circle passing through the Hook and loop coupling layer.

[0183] Let us assume that the value of 1 is approximately twice the value of the permissible elongation [l], since shear deformation occurs in two hook and loop sections at the ends of the shafts, and we will consider [l] as a limiter of the relative angle of rotation of the shafts:

[00006]$\begin{array}{cc}\left[\right]=2\left[1\right]/R.& \left(F\right)\end{array}$

[0184] The following limiting parameters are introduced for working with hook and loop connections: [0185] coefficient of safety factor [n], (see equation D); [0186] permissible elongation of the hook and loop connection[l]; [0187] admissible angle of rotation of the shafts[], (equation F)

[0188] These parameters limit the transmitted force and should increase the reliability and durability of the joint. They need to be specified during testing for each type of hook and loop joints.

2. Protective Devices

[0189] Description of various protective arrangements is provided below.

A. Protective Devices Associated with Flat Surfaces.

[0190] FIGS. 19a, 19b, 19c1, 19c2, 19d, 19e and 19f are the views showing protection arrangement for flat surfaces In some embodiments of protection devices a thin adhesive tape (Scotch tape for example) 54 (FIG. 19a, b) is wrapped with an interference fit around the hook and loop wings, including their free ends is used. Applying the adhesive tape also has some squeezing positive effect on the hook and loop arrangements. Wrapping the hook and loop joint with tape also protects the hook and loop from contamination during use.

[0191] In FIG. 19c, a clamp 55 is shown, consisting of a section of hook and loop part 56. The opposite side of the part 56 has a hook and loop counterpart portion 57. The clamp is connected or sewn to one of the hook and loop parts. A reusable hook and loop cable ties can be used for this purpose.

B. Protective Devices Associated with Cylindrical Surfaces.

[0192] FIGS. 20a, 20b, 20c, 20d, 20e, 20f and 20g are the views showing protection arrangement for cylindrical surfaces. Self-adhesive Loop Tape 65 is glued to the ends of two rods 63 and 64 (FIG. 20a). Hook Tape 66 is placed on top, the length of which is equal to the perimeter of the outer diameter of the glued loop tape. By wrapping the hook tape in the joint 67, a small gap may be created. Regardless of the size of the gap, when the torque M is transmitted through the joint along the joint, the edges of the hook tape 66 shift (FIG. 20b). To reduce and minimize the shift along the joint and ensure the joint is functional, a strip of thin rigid adhesive tape 68 is glued (FIG. 20c).

[0193] Alternatively, strips of the same tape 69 are placed around the circumference of the circle above the overlap joint (FIG. 20d). It is also contemplated to use both embodiments simultaneously (FIG. 20c, d). The adhesive properties of the tape should be sufficient to reliably adhere to the materials at the application sites.

[0194] If it is necessary to disassemble the hook and loop arrangement and it is difficult to separate the adhesive tape by hands, it is possible to cut the connection neatly without damaging the parts. In all cases, adhesive tape should be considered a consumable material. The thin sticky tape strips 68 and 69 act as protective arrangements.

[0195] Tightening a piece of adhesive tape around the perimeter of the hook and loop connection also has some squeezing effect on the hook and loop arrangement. The adhesive tape also protects the hook and loop connection from contamination.

[0196] Another embodiment of protective device is shown in FIG. 20d. In this arrangement on the edge of the loop tape 66 is attached a strip of hook tape 71; the other end of the loop tape 66 is superimposed on the hook tape 71 and pressed by hand. To enhance the protection, as well as in the case of reverse operation of the connection, a strip of thin tape 68 can be applied to the ends of the hook tape (FIG. 20e).

[0197] Other protective options are within the scope of the invention.

[0198] C. FIGS. 21a-21f illustrate various parts and materials that can be used as protective arrangements. Clamps and ties are used to surround hook and loop arrangement on cylindrical surfaces. The clamps are tightened with a force to ensure that they are held at the exterior of the hook and loop arrangement. This force can cause some deformation of the hooks under the clamps, which will lead to strengthening of the connection. Ropes and threads are also used as clamps with fixing the ends by tying knots or by any other conventional means.

[0199] When installing hook and loop fastener clamps on shafts with unidirectional rotation, it can be considered that the incoming air flow does not contribute to the opening of the clamp.

[0200] Shown in FIG. 21 elements can also be used for the protection on flat surfaces instead of adhesive tape 54 (FIG. 19).

D. Protective Devices Applicable for Connection of Bars to Parts Using the Clamps.

[0201] A special group protective devices is represented by connections with power elements in the form of buckles and clamps, or simply clamps for fastening rods, poles, cables, pipes, etc. to various objects (for example, bags) and parts, or vice versa, fastening objects to rods, sticks, cables, pipes, etc. FIGS. 22a, 22b, 22c and 22d are the views showing fastening of the rod by means of buckles and a clamp.

[0202] Such connections typically consist of three components: a rod 74 (FIG. 22a), fastening elements on part 79 in the form of two double slot buckles 76 (FIG. 22b), and a clamp 75 (FIG. 22c), on which the book and loop sections are arranged in a certain order, and which in a certain way, through the slots of the buckles they surround the rod 74.

[0203] A self-adhesive loop tape 84 is attached to the rod 74 around its exterior. Two buckles 76 are attached to part 79 by a buckle holder 78. Clamp 75 has a stopper 80. In this example, the clamp is a loop tape 77 with face 12. Hook Tapes 81, 82 and 83 are sewn onto it at the appropriate locations with orientation relative to face 12 (FIG. 22c).

[0204] The clamp is inserted into the slot a of the left buckle (FIG. 22b, d), then in the slots b and c of the right buckle, it is pulled up to the stop of the stopper 80 in the left buckle.

[0205] Next, a rod 74 is installed between the buckles, with the Loop Tape 84 being pressed against the Hook Tapes 81 on the clamp. Then the clamp is pulled, bent around the rod 74 and is passed through the slots a and d of the left buckle, pulled with the maximum effort of the hand; Hook Tapes 82 on the clamp contact the Loop Tape on the stem. The end of the clamp goes around the rod, the loop tape of the clamp with the front side 12 is connected to the Hook Tapes 83. The clamp is passed through slot c of the right buckle and tightened. If necessary, for a more reliable connection of the end of the clamp, it is additionally attached to Hook Tapes 85 on part 79

[0206] The connection between rod 74 and part 79 is made through hook and loop fastener parts 84 on the rods and 81, 82 on the clamp. The connection is protected by a section of the clamp gh and passing the end of the clamp through the slots a, d and c of the buckles, over buckles connectors e and f, and with the hook tapes section 85 onto part 79 (FIG. 22c, d).

[0207] FIGS. 23a, 23b, 23c, 23d and 23e are the views showing various types of protection arrangements for clamp connections. FIGS. 23a, b, c show another example of attaching the rod 74 to the part 79 using buckles and a clamp. In all cases considered, the rod 74 has a self-adhesive loop tape 84. FIG. 23a shows clamp 75, which is loop tape 77, where hook tapes 82 and 83 are sewn to each other on both sides of the clamp at appropriate locations. The connection is secured with a clamp from point A. From there, it is inserted into the groove of the right buckle; the hook and loop fastener 83 part connects to the hook and loop fastener 77 part of the clamp itself. Protection can be increased by placing a piece of hook tape 86 on the yoke next to the stopper 80 and using the double slot buckle 76 (FIG. 23b) or by creating an additional hook and loop fastener connection 85-77 on the left side of the left buckle (FIG. 23c).

[0208] Note that in all discussed buckle joints, they are placed on part 79, so that when the joint is assembled and the clamp is pulled, the buckles are tightly attracted to the rod 74, creating additional compression in the hook and loop joints. Also, when passing the clamp through the buckles, it is pinched due to bends and pressing against the rod. In the figures, the buckles are shown spaced from the bar for ease of explanation of how the joint works.

[0209] FIGS. 23d, e show examples of fastening a rod to a part using a single clamp. The device shown in FIG. 23d, consists of loop tape 77 sewn together and hook tape 87 folded in half. The clamp is attached to part 79 at the junction of the hook and loop tapes. Shaft 74 wraps around hook tape 87 on the left side and loop tape 77 wraps around the shaft on the right and attaches to hook tape 85 to part 79. Protection is provided by loop tape 77 and the outside of hook tape 87 of the clamp, as well as an additional hook and loop connection 85-77.

[0210] FIG. 23e shows the attachment of the rod 74 to a separate part or a bridge 89, which can be attached in turn to the part 90. The connection uses the same clamp as in the previously discussed example (FIG. 23d); it is attached to the bridge 89, a part of the hook and loop-hook 88 is attached to the bottom of the bridge. The connection is assembled in the same way as in the previous example, with the difference that the end of the clamp 77 is connected to the hook and loop part 88 at the bottom of the bridge. This ensures the concealment of the clamp fastening and increase the quality of the protection.

[0211] FIGS. 24a, 24b, 24c. 24d1 and 24d2 show various views of the collar stoppers securing its end to or near the buckle. Stoppers can be made by bending the end of the clamp 75 in 3 and 4 layers with fixation by a thread or heat seam, while the thickness of the folded parts must exceed the gap 93 in the buckle 76 (FIG. 24a).

[0212] The stoppers can be made, for example, of metal 80, 94 and can be larger than the width of the buckle slot (FIG. 24b); or made of another rigid material 95 and attached to the clamp with a seam 91 or a rivet 96 (FIG. 24c). The clamp can be fixed next to the buckle or sewn to the buckle bridge (FIG. 24d). The above examples discussed protective arrangements for hook and loop joints wherein the parts can be squeezed by human hands.

The following requirements are applicable for the component connections utilizing hook and loop arrangements.

[0213] 1. Compression of hook and loop joint should not lead to irreversible deformations of the elements including: changing the shape of the hooks, decreasing their height, breaking the loops, pulling the loops out, etc.

[0214] 2. Breaking the hook and loop joint under load is considered to be an extreme, emergency situation, unacceptable during normal operation. To prevent this, the following requirements must be met when designing and operating the joint: [0215] provide a tensile safety margin, i.e., the recommended maximum working force transmitted by the connection should be less than the force of breaking the connection; [0216] Hook and loop compression of the joint allows preservation of its initial physical and mechanical properties and dimensions after unloading.
The tensile strength should also consider the quality and accuracy of the assembly of the hook and loop connection of the parts and the placement of the squeezing device on them. In all cases, the connection must be performance tested.

[0217] 3. It is advisable when designing devices with hook and loop arrangement, in which tangential forces act constantly in one direction, to use special hook and loop-hooks, in which all rows of technological loops for hooks should be cut with orientation in one direction. In this case the hook and loop joint will be able to transmit greater force.

[0218] 4. The hook and loop material must be suitable for the operating conditions of the joint.

[0219] 5. When using self-adhesive hook and loop tapes, the respective adhesive layer should withstand the working loads and operating conditions, not to shift or peel off under the influence of a long-term load, and the ends of the tape in a free state without pressing force should not peel off over time from parts in areas having a curvature. Adequate protective arrangements must be provided for this purpose.

[0220] 6. For joints using hook and loop arrangements, it is desirable to establish a calendar life span and the recommended number of assembly-loading and unloading-disassembly cycles under operating conditions, during which the required fastening efficiency and wear resistance are provided. It is known that the number of opening-closing cycles of hook and loop arrangements made of nylon is not less than 10,000. Over time and depending on the number of loading-unloading-disassembly cycles, the strength characteristics of the hook and loop arrangement may change.

[0221] The type of joints using hook and loop arrangements of the invention are not known in the prior art.

[0222] The currently used hook and loop joint with short-term hand squeezing, after the hook and loop parts are placed on top of each other, is not subject to the proposed method in the following circumstances: the connection does not require protection from unwanted, unintentional delamination of the hook and loop under a load, and in which all the needs for transferring tensile (tangential) forces are fully provided due to the adhesive property of hook and loop in the form of adhesion of hooks and loops when they are briefly squeezed by a human hand.

DETAILED DISCLOSURE OF SPECIFIC EMBODIMENTS OF THE INVENTED TECHNOLOGY

[0223] The method of the invention is implemented as described below. Loop-type tape is attached to one of the joint parts, and hook-type tape is attached to another joint part. The parts are superimposed by the front sides of the hook and loop parts on top of each other and can be compressed by fingers of a user (as typical in the conventional hook and loop joints). Further hook and loop joint is equipped with additional devices and elements provided to ensure that the compressed state is maintained during the entire joint operation. The protective devices prevent inadvertent peeling off the elements or provide further compression of the hook and loop joint from outside and fix this compression-by-compression devices.

[0224] To disassemble the joint, the protection or compression devices are removed, and the hook-type and loop-type elements are manually disconnected by peeling them off. As a result of providing hook and loop joint with additional devices and elements, the book and loop joint receives the following new qualities: the ability to work safely and reliably in the loaded state and acquires the ability to transfer large forces with the same dimensions of hook and loop arrangements.

[0225] The proposed method and devices using hook and loop arrangements have the following advantages: [0226] simplicity of the joint design; [0227] ease and simplicity of manufacture, assembly and disassembly of the joint; [0228] low weight of used elements and compression devices; [0229] the ability to manufacture a joint without metal parts, and parts subject to corrosion in aggressive environments; for example, in the aquatic environment; [0230] flanges in flange and end couplings can be made of easily processed materials (for example, wood, plywood) and Hook and loop parts can be attached to them with staples, nails, screws, etc. [0231] allow greater tolerance errors in the alignment and misalignment of the shafts when transmitting torque; [0232] simplify attachment to joint parts when using self-adhesive hook and loop arrangement. This makes it easier to repair the joint when a hook and loop parts needs to be replaced; [0233] the parts to which hook and loop arrangement is attached and the applicable compression devices do not have a noticeable effect on the deformation and strength characteristics of the parts to be joined; [0234] as power elements of compressive devices, it is possible to use simple parts, for example, shaped springs, screw connections, clamps, cable tie, etc. [0235] the possibility of fastening to ski poles, for Nordic walking, for the elderly, etc., for example, bags, sports equipment and other items.
Recommendations for using hook and loop joints are as follows:

[0236] A. The magnitude of the transmitted tangential forces in the joint can be increased by the following factors: [0237] increase in the contact area of hook and loop arrangement, i.e., increasing the number of hooks in the contact area; [0238] increase the degree of compression, taking into account the margin of safety; [0239] uniform compression of all hooks in the contact zone; [0240] use of hook and loop arrangements with hooks of one orientation, where possible. [0241] in connections transmitting forces in different directions, hooks of forward and reverse orientation should be oriented taking into account the prevailing direction of action of the forces; [0242] of interest is the modification of book and loop-book tape, in which hooks of forward and backward orientation are located on the same leg; in this case, the hook and loop arrangement can be squeezed until the base of the Hook and loop-loop comes into contact with the leg on the hook and loop-hook at the branch of the hooks: in addition, in this modification, all hooks in all rows along the tape are applicable.
B. Features of self-adhesive hook and loop arrangements. [0243] In case of self-adhesive hook and loop elements, over time, the edges at the joint in the free state (in the disassembled joint) peel off on the surfaces of parts with a large curvature. This is especially so for the hook tapes. This is because such bases are more rigid than the bases of the loop tapes. Therefore, it is better in these cases to use self-adhesive loop tapes, as they are thinner and softer.

[0244] The following can be used to prevent hook and loop parts from peeling off on convex cylindrical surfaces: [0245] form (for example, by heating) pieces of hook and loop parts at fixed intervals (equal to diameters of the parts) in order to remove residual bending stresses in the bases of hook and loop parts; [0246] place narrow segment 71 (FIG. 20g), for example, of Loop Tape on shafts 63 and 64 with hook tape being installed on the shafts; [0247] pull off the book and loop fastener with thin threads (in the hook tape, place the threads between the hooks); [0248] other arrangements are within the scope of the invention.
In some instances, glue in self-adhesive tape is weaker than the hook and loop fastener interlayer itself.

[0249] C. Recommendations for the design, assembly and use of joints using Hook and loop arrangements. [0250] To reduce the effect of different deformations of the hook and loop tapes during stretching, as well as to increase the strength of the connection parts, the hook and loop parts can be sewn to the tape along the contour. It is possible to add additional seams in the middle along the braid. [0251] In the event that frequent disassembly of the hook and loop joint is required, a smooth piece of tape can be attached to the free end of the hook and loop piece, which is easy to grasp with fingers. In the case of using the protective devices in the joint, the tape must be also protected (FIG. 25a). [0252] In the case of passing the clamp, with the hook and loop parts attached to it, through a narrow opening in which the hook and loop part is already located, to prevent unwanted adhesion of their parts, it is possible to use a separating pad. Such pad, for example, can be made of paper, and can be removed after installing and tightening the clamp (FIG. 25b).

[0253] It is necessary to provide for hook and loop joint with time for the rest between disassembly and subsequent assembly for the relaxation of hooks. It is possible to warm parts of hook and loop assembly with warm air (by hairdryer for example). [0254] Spare, interchangeable mating hook parts can be utilized in case of frequent work requiring assemblies and dis-assemblies of the joint with small breaks between them in the disassembled state. This is especially so if the working conditions of the joint do not allow the hooks to provide sufficient relaxation time. [0255] The hook and loop tapes can be placed at the same time in connection with the loop and hook tapes, respectively. However, some combinations of hook and loop elements on the details of specific connections have their advantages. [0256] When disassembling joints with parts of self-adhesive hook and loop elements attached to rigid parts, it is sometimes necessary to create large amounts of force. Therefore, mandrels and disassembly devices can be provided, and special places should be identified on the connection parts for the insertion of such devices.

[0257] D. Care and cleaning of hook and loop joints.

The surfaces of hook and loop parts, especially hook tapes, are susceptible to capture various types of contaminants: pile, thread, fibers, hair, fluff, dust, etc. Clogged hook and loop joints lose their properties, cease to reliably transmit the efforts applied to it. Timely cleaning of hook and loop parts helps to restore its functionality and extend the life span of the joint.

[0258] Before each assembly of the joint, it is necessary to inspect the Hook and loop parts and check for contamination at the front and back sides. Depending on the type of contamination, the following can be used during cleaning: applying adhesive tape (Scotch tape) to the Hook and loop-hook, pressing and pulling it off, special hard brushes, pointed tweezers, etc. Clean with caution along the rows of hooks, being careful not to damage them.

[0259] After cleaning, the hook and loop parts can be sprayed with anti-static spray to help minimize subsequent hook and loop contamination.

[0260] Sometimes, when working with self-adhesive hook and loop parts, when disassembling a joint, due to the creation of large local forces at the edge, the adhesive is squeezed out and contaminates the hook and loop work surface and parts. In such cases, it is recommended to choose another method for disassembly or use a disassembly tool and clean the stained areas with a solvent.

[0261] In a free state during long-term storage, the hook and loop parts should either be connected without compression by a squeezer, or to remain in a separate state, but protected from possible various contaminants, for example, by placing into protective covers.

[0262] During operation, hook and loop joints, if possible, should be also placed into protective covers.

[0263] The transmission of tensile (tangential) forces is one of the main aspects of the hook and loop joint of the invention. Tangential forces (stresses) are mainly responsible for the transmission of the tensile forces and torques. The stratification/disassembly of hook and loop elements by human fingers in the invention often plays an auxiliary role and is used only when dismantling the joint.

[0264] The following applications of the invention are possible in various technical fields. For this purpose, detachable fixed joints (devices) using hook and loop are divided into the following groups: [0265] 1. Joints to transfer of tensile forces through flat parts such as flexible tapes made of woven materials (braid), plastic, metal, etc., for example, for transportation or fastening of objects; [0266] 2. Joints for transmission of torque and combined loads:
a. sleeve couplings, connection and extension of rods, shafts, sticks;
b. couplings for transmitting torque through outer surfaces-flange couplings,
c. couplings for transmitting torque through end surfaces-end couplings; [0267] 3. fastening sticks, rods to objects using clamps.

[0268] Each of group of hook and loop joints is discussed below.

Joint Group 1Transmission of Tensile Forces Through Flat Parts.

[0269] A basic joint is formed by superimposed hook and loop parts. Consider now a unitary joint 21 (FIG. 8a). A compression device consisting of two rigid plates 107 and 108 (FIG. 26) is applied to the wings of the hook and loop parts (the contact zone along the length L). In FIG. 26 compression is applied by a leaf spring 109, which creates a normal force N. Other plate compression methods are also applicable (FIG. 13).

Such unitary joints with the compression devices can transmit a tensile force P. In the contact zone (interlayer), the force P is converted into shear stresses, accepted by the hooks and loops of the Hook and loop parts.

[0270] Unitary joints can be arranged into assemblies of several joints substantially parallel to each other and form a flat assembly. A squeezing device is also superimposed on the flat units.

[0271] It is considered that the assembly of an even number of unitary joints is more compact and technologically advanced in manufacture.

[0272] FIGS. 27a, 27b, 27c, 27d and 27e show the flat units composed of two unitary joints. Four options of the respective assembly are discussed below: [0273] Options a, bunitary connections are assembled by the respective tails. The front sides of the hook and loop parts are directed inward or outward; and provided with a plane of symmetry 110 (FIG. 27a, b), or [0274] Options e, dunitary joints are assembled together in different combinations (FIG. 27c, d). [0275] Options a, b have certain advantages, since they are more technologically advanced and compact, convenient to assemble and disassemble, the symmetrical arrangement of unitary joints neutralizes the negative effect of Q forces (FIG. 12b, c).

[0276] In FIG. 28 a flat assembly is illustrated consisting of four unitary joints. Buckles (D-Ring) 112 can be attached to the ends of the tails, so as to make the assembly as an independent unit.

[0277] The unitary joints in the flat assembly should have the same size to assure uniform compression. In a flat unit, the amount of compression by a common compressor increases proportionally to the number of unitary joints.

[0278] By utilizing flat units (FIG. 27, 28), it is possible to create a compact joint that transfers large forces P from a unit of length (unit of area) hook and loop arrangement. This is because the energy intensity of a flat unit as compared to one unitary unit increases approximately in proportion to the number of unitary units. Only thickness increases in the flat unit itself. The number of unitary joints in a flat assembly may be greater than the four shown in the drawing.

[0279] With a certain degree of compression of a unitary joint, when it transfers great forces, the strength of the bases 1 and 10 of the hook and loop parts is not enough. Therefore, the Hook and loop parts along the length of the contact area are attached by sewing or otherwise attaching to a strong base, and then the working forces are transmitted through it.

[0280] Group 1 joints can be used to transmit tensile forces. Such joints can be also used as safety, emergency devices that disconnect attached parts when the permissible load is exceeded. Flat units can be used without compressing devices, but with protective devices.

[0281] FIG. 19d shows a flat unit assembly consisting of 2-unit joints without a compressing device. The outer wings 59 and 60 are protected at the ends with hook and loop fasteners at a short length L*. This assures the protection of the joint and its ability to transmit tensile forces by two unitary joints with a working length L. However, if the length L* is increased, it becomes possible to increase the transmitted force by including two new sections L*. When the equality L*=L is reached, a flat unit of two unitary joints turns into a flat assembly consisting of four-unit unitary joints (FIG. 19e).

[0282] This new assembly can be viewed from two perspectives:

The assembly consisting of two unitary joints, but with a protection that increases the transmitted force. Due to the lack of protective devises on wings 61 and 62, which themselves act as protection for wings 59 and 60, they can be considered as protection devices of a higher degree for a flat assembly of two unitary joints.
If the wings 61 and 62 are protected, for example, by applying a thin adhesive tape 54, then the new assembly can be considered as a flat assembly of four-unit unitary joints (FIG. 19f). Accordingly, the value of the permissible transmitted force also changes.

[0283] FIGS. 29a, 29b, 29c and 29d are the views showing a handle toggle clamp. In particular, FIG. 29 show a device consisting of part 115 and handle toggle clamp 116. On a flat clamp 117, mounted on a clamp and part 115 are installed, for example, self-adhesive loop tapes 118 and 119, respectively.

[0284] In the open, non-operational position of clamp 116 (FIG. 29a, the lever 121 is raised), the part 120 with the hook tapes 122 and 123 fixed on both sides is mounted on the loop tape 119 counterpart. By turning the lever 121 downward, the clamp 117 freely falls onto the part 120 and is presses against the loop tape 122.

[0285] The clamp 117 at the moment of initial compression of the hook and loop parts is approximately parallel to the surface to which the hook and loop part 119 is attached. Compression of the entire hook and loop set to the required thickness H, which is set, for example, by screws 31, ends through a small angle of rotation of the lever 121 down by the locking in the working position (FIG. 29c).

[0286] To unlock Clamp, lever 121 is rotated upward in the direction of the arrow (FIG. 29d) by a small angle, with the hook and loop compressing force removed. But for clamp to be fully open, it is necessary to apply a relatively large force to the lever directed almost perpendicularly to the entire surface of the contact zone with the simultaneous separation of all the loops from the hooks in hook and loop arrangement.

[0287] This can be avoided in the following manner. The lever 121 rises a small angle, clamp is unlocked, the compressive force is removed from the hook and loop unit. Lever 121 is released. Next, part 120 is easily pulled out of clamp by a sharp upward movement and slightly upward (FIG. 29d, arrow at an angle ). In this case, the clamp 117 leans upward and at the same time, all hook and loop parts are disconnected in the same way as manual disconnection. Item 120 is completely freed.

[0288] In the example considered, parts of hook and loop fasteners 118 and 119 are mounted on parts 115 and 117 of the compression device. Elements with hook and loop fastener parts form a flat assembly of their two-dimensional unitary connections (FIG. 27b). Handle of toggle clamp operates as a compressive force element.

[0289] FIG. 30 shows examples of the use of a device with a handle toggle clamp type compression device on a trolley (FIG. 30a) and when hanging products on a wall (FIG. 30b). To free the trolley and remove the load from the wall, the clamp should be unlocked as described above. When removing the load from the wall, it is necessary to prevent it from falling.

[0290] Hook and loop parts can be attached to connection elements in the following manner: [0291] by rivets, brackets, nails, screws, screws, screws with nuts, staples; [0292] by coverage with clamps along the outer contour of the hook and loop part; [0293] by sewing directly to the part; [0294] by sewing or welding to an intermediate element, which is then attached to the part; [0295] by gluing (self-adhesive hook and loop arrangement); double-sided adhesive tape; [0296] by heat welding; [0297] by binding by wrapping around a part with a thin thread; [0298] Hook and loop parts can transmit forces directly through their bases; [0299] and in other ways.

[0300] The compressing arrangement is an independent connection/joint unit, which forms a part of a flat unit. For ease of use of the connection, compressing plates 126 and 127 can be attached, for example, with braid 128 and 129 to one of the tails of, for example, 125 assembly (FIG. 31). This facilitates disassembly and reassembly and use of the connection unit.

[0301] FIGS. 31a, 31b and 31c are the views showing a compressor holder. In particular, FIG. 31 show options for securing a compressing arrangement on one of the connection tails. In the embodiment of FIG. 31c, Hook and loop pieces are attached to the gripping plates so that they become the working elements of unitary joints.

[0302] If, for some reason, the load on the joint may be higher than the maximum permissible (case of peak load), then to protect it from unwanted rupture of the joint, a rigid stopper 131 made of metal for example can be installed on it (FIG. 32a). This stopper at the moment of operation can, for example, close the contacts 132 of the sensor circuit, signaling the occurrence of an emergency.

[0303] Also, at the end of the wings of the central part 133 of the flat assembly joint, an enlargement in the form of, for example, a wedge 135 can be provided in front of the compressor/squeezer. The wedge in the contact area increases the local compression of hook and loop fastener and the transmitted force will also increase.

Connection/Joint Group 2a Including Sleeve Couplings, Joint and Extension of Rods, Shafts, Sticks.

[0304] FIGS. 15, 16, 17 and 18 show embodiments of sleeve couplings with compressing arrangements, and FIG. 20 and FIG. 21 show embodiments of protective arrangements. If there is no gap between the ends of the sticks, rods at the junction, such connection/joint facilitates the transmission of compression forces along the axis.

[0305] FIGS. 33a, 33b. 33c and 33d are the views showing embodiments for a bar connection. In particular, FIG. 33 show the embodiments for using hook and loop joints with compressing arrangements in an assembly of volumetric bar structures. Spring rings 48 are shown as force elements of the compressor, but other force elements can be also used (FIG. 18). Half rings 43 and rods 136 are connected to each other at different angles, for example, by welding.

[0306] Hook and loop parts are glued to half rings 43 and pipe 137 from the inside. Hook and loop fastener counterparts are glued to the rods 136 from outside. FIG. 33c shows a connection/joint with a half-ring 43 similar to that of FIG. 16c. FIG. 33d shows a connection/joint similar to that of FIG. 16e.

[0307] Assembly and disassembly of the structure must be carried out in a specific sequence.

[0308] To facilitate assembly of a structure, it is possible to start with a preliminary assembly: [0309] to install spring rings on the rods; [0310] during assembly, the Hook and loop parts are separated by a gasket, for example, made of paper; [0311] spring rings are installed on all connections and the design is verified.

[0312] After assembly, one by one, from each joint, the spring rings are moved to the sides, the gasket between the hook and loop parts are removed and the spring rings are returned to their places.

[0313] Disassembly of the structure can be started, for example, by moving to the sides spring rings from the connections E and F (FIG. 33b). Then we apply a force to the top of the rods 136 in the direction of arrow G, creating a torque M (see FIG. 7f), and sever the hook and loop at connections E and F. Then remove the springs from all the remaining connections, create by hand or by using a tool the force in the direction of the arrow H (FIG. 7f) and disconnect connections B and C.

Connection Group 2b Including Flange Couplings

[0314] FIGS. 34a, 34b, 34c, 34d and 34e are the views illustrating a flange coupling. Specifically, FIG. 34a shows a flange coupling. On the coaxial shafts 138 and 140 with a small clearance 142, flanges 139 and 141 having wide external cylindrical surfaces are attached. On these cylindrical surfaces, the segments of the hook or loop parts 143 and 144 are attached around circumference. There may be a small gap between the ends of the segments at the junction. Depending on the material and design of the flanges, hook or loop pieces can be attached to them with screws, nails, paper clips, glue (Self-adhesive hook or loop tape), double-sided adhesive tape, welding and other methods.

[0315] On top of two segments around the circumference, a second, counterpart loop part 145 is superimposed. The width of the loop part is approximately equal to the width of both segments plus the gap 142 between the flanges. There may be a small gap between the ends of the loop part at the junction.

[0316] The hook tape and loop tape contact areas on the flanges are pulled together by separate compression devices/arrangements. In this case they are pulled directly by their force elements, for example, cable tie 146. Other types of compression arrangements are shown in FIGS. 15, 16, 17, 18.

[0317] A torque M.sub.1 is applied to the shaft 138 in the direction of the arrow n (FIG. 34b), overcoming the moment of resistance M.sub.2 on the shaft 140. The torque M.sub.1 is transmitted to the shaft 140 through the loop tape 145.

[0318] FIG. 34b shows how the pulling force from the shaft 138 is transmitted to the shaft 140 through the interlayer 18the contact zone of the hook and loop fastener parts (FIG. 6). Unitary hook and loop arrangement is used. As an example, from the shaft 138 to the flange 139, from the flange 139 the force is transmitted through chain: book 147, loop 148, to loop 149 and then to hook 150. From FIG. 32b it follows that the hooks 147 and 150 are multidirectional, i.e. in one case, a series of hooks 15 are used, and in another case series of hooks 16 (FIG. 4) are applied. As a result of this, in the region 151 (FIG. 34c) of the upper part of the loop tape in the region above the gap 142, shear torsional deformations occur due to the elasticity of the base of the upper part of the loop tape 145.

[0319] To reduce shear deformations in the upper part of the loop tape 145, it is possible to use a thin flexible strip 152 of metal, plastic, braid or other material that is applied or attached in any way (sewing, gluing, heat welding, etc. FIG. 34e) to the upper part 145. The width of the strip 152 should capture the expected zone of shear deformations 151.

[0320] Compression of the hook and loop fastener joint in the case of the reinforcement 152 of the upper Hook and loop part can be accomplish by the squeezer/compression pads 39 (FIG. 15c, g), having a stepped profile shape, taking into account the thickness of the strip 152 (FIG. 34d, e).

[0321] The flange coupling can transmit torque clockwise and counterclockwise. If the flange coupling is capable of transmitting torque M.sub.1 without compression arrangements, then the devices and protection elements shown in FIG. 20, 21 are used.

[0322] The coupling is disassembled as follows: all elements of the compression device or protective device are removed from the coupling, starting from the junction of the loop tape 145 over the edge, followed by disconnection from book parts 143 and 144 on flanges.

Connection Group 2e Including End Couplings

[0323] FIG. 35 shows an end coupling. A flange 154 is mounted on the drive shaft 153, and a flange 157 with a sleeve 158 mounted on the shaft. 159; the shaft 159 and the sleeve 158 can move relative to each other only in the axial direction. The above elements form, for example, a spline connection. Parts of hook and loop fasteners 163 and 164 are attached between the flanges 154 and 157 (FIG. 35b). Hook and loop parts through flanges 154 and 157 are pressed against each other by spring 160.

[0324] On the flange 157, a ring with a collar 156 is fixed, by which it is possible to move the flange 157 away from the flange 154 by the shutdown handle 161, compressing the spring 160. The operating and disconnected positions of the flange 157 are fixed by a stopper 162. When the flanges are disconnected, the force from the lever is applied perpendicular to the entire surface hook and loop contact at the same time. It is advisable to disconnect when the shafts are stationary. However, if necessary, the shutdown handle can be also used to achieve the emergency stop of the driven shaft 159.

[0325] By attaching the hook and loop portions to sectors 163 and 164 (FIG. 35b), the forward and the reverse orientation hooks 165 and 166 can be optimally oriented to transmit maximum forces.

[0326] The function of the power element of the hook and loop compressor is carried out by the spring 160.

[0327] The clutch/coupling can transmit torque clockwise and counterclockwise. The considered mechanical coupling functionally corresponds to the known friction couplings, the transmission of rotational motion occurs due to the adhesive properties of hook and loop arrangement, improved due to the pressure of the spring.

[0328] Instead of a spring, magnets, for example, can be used as a force/power element. On one side of the book and loop connection, magnets are installed in a flange made of non-magnetic material, and on the other side, a steel washer is provided. This assures a compact design. When choosing the strength of the magnets, the thickness of the hook and loop should be considered.

[0329] FIG. 36 shows an embodiment of an end sleeve in which, as compared to FIG. 35, the second flange is mounted on the shaft 168, so as to prevent axial movement relative to the shaft. Further, there is no spring, and the compression of the hook and loop parts is performed during assembly due to the structural dimension C using an adjusting shim 171.

[0330] When the coupling is disassembled, the cover 170 is removed and a force is applied perpendicular to the shaft 153 until the Hook and loop parts are separated (see FIGS. 7e, f, force R).

Connection Group 3

[0331] These connections are applicable for fastening poles, rods to objects, as well as fastening objects to rods and poles, for example, fastening bags for personal belongings to ski poles, Nordic walking poles, in auxiliary equipment for mobility (movement) of the elderly and disabled (for example, walking sticks), tourist and mountaineering equipment, orthopedics, prostheses, fastening cables in the lines of laying, etc. using clamps.

[0332] The connection with two slot buckles is discussed in the protection section and is shown in FIG. 22. Various types of stoppers for clamps are discussed in the protection section and shown in FIG. 24

[0333] The connection shown in FIGS. 37a, 37b, 37c and 37d differs from the connection in FIG. 22 in that hook tape 177 is attached to the buckle holder 78 between the buckles, and the hook tape 85 is attached to base 79 on the left side of the buckles.

[0334] The clamp is passed through the slot of the left buckle until the stopper 80 contacts the buckle. The rod 74 is positioned so that its Loop Tape 84 is positioned on Hook Tape 177 between the buckles. The clamp is placed on top and fixes the Hook Tape 82. Then the clamp is threaded into the slot of the right buckle, tightened, around the buckle and rests on the Hook Tape 83 on the clamp. The clamp is tightened around the left buckle and its end is attached to Hook Tape 85 on base 79. FIG. 37d shows an embodiment of attaching the end of the clamp to a Hook Tape 86 attached to the clamp near the stopper.

[0335] If necessary, for a more reliable connection of the end of the clamp, instead of the unitary slot of the left buckle 175, a double slot buckle 76 can be used, and the end of the clamp is led into the upper slot (FIG. 37d).

[0336] The connection between rod 74 and base 79 is made through loop tape 84 on the rod, hook tape 177 on the part and 82 on the clamp. The protective function is provided in the joint and carried by the following elements: the clamp, starting from point A, hook tape 83 of the clamp, loop tape 77 of the clamp, hook tape 85 on the base 79 or 86 on the clamp, as well as buckle 76 (FIG. 23d).

[0337] FIGS. 38a, 38b and 38c are the views showing fastening the rod by a clamp to the parts. In the joints of group 3, instead of buckles, it is possible to use a part with slots for passing a clamp to which the rod is connected. FIG. 38 shows two configurations of such parts: flat 183 (FIG. 38a, b) and cylindrical 184 (FIG. 38c). In the parts, the cuts are made similar to the slots in the buckles.

[0338] The mutual arrangement of elements in the connection is shown in FIG. 38. FIGS. 38a, c corresponds to the buckle embodiment shown in FIG. 22, and FIG. 38b corresponds to the embodiment of FIG. 37.

[0339] It is possible to use clamp 75 without buckles and slots in the part attached to the rod.

[0340] In FIG. 39, a clamp is attached to the base 79, consisting of hook tape 87 and loop tape 77 connected together. A segment of hook tape 85 is attached to the base 79 (FIG. 23d).

[0341] The rod 74 with a ring of loop tape 84 is applied to the clamp at the place where the hook and loop parts are joint. The tail 87 of the clamp covers the rod on the left side, after that the tail 77 is applied with tension to the tail 87 from the right side and then rests on the hook and tape 85.

[0342] It is possible to provide the joint/connection, into which an additional structural protective element is introduced, which ensures the hidden fastening of the end of the clamp. This embodiment complicates the disassembly of the joint (FIG. 40). In general, FIGS. 40a, 40b and 40c are the views also showing securing the rod with a clamp.

[0343] The joint/connection differs from the joint/connection of FIG. 39 in that the function of the base 79 is carried out by an independent part-bridge 89, which can be attached to another part 90 using screws, rivets, seams, etc. The bridge can be formed as a rigid structure. A clamp is fixed on the top of the bridge, and hook tape 88 is attached at the bottom. The joint is assembled in the same way as in FIG. 39, but at the final stage of the assembly, the end of the clamp e (FIGS. 40a, c) passes through the window between the bridge 89 and part 90 and fixed to the hook tape 88.

[0344] To prevent the hook tape of the clamp from clinging/attaching to the loop tape 88 during the insertion of the end of the clamp e into the window, it is possible to initially insert, for example, paper, then insert the clamp from below, remove the paper and squeeze the hook and loop arrangement (FIG. 25b).

[0345] FIGS. 41a, 41b and 41c are the views also showing securing the rod with a clamp and related connection. The joint/connection shown in FIG. 41 differs from the connection in FIG. 40 in that the clamp 197 is made as a separate element, which is not rigidly attached to any other element. On the bridge 89. Hook and loop-hooks 198 and 88 are attached above and below. The bridge is fixed to the part 90.

[0346] The clip consists of sections of hook 87 and loop 77 connected to each other, hook 201 is attached to the loop from the inside.

[0347] The connection is then assembled in the following order:

On the hook tape 198 of the bridge 89, the rod 74 is installed with the loop tape 84. The tail 87 of the clamp is applied to the ring 84 starting from the place a and is drawn around the rod. The clamp is pulled through the window 200 under the bridge, connected to the hook tape 88. Next, the clamp covers the tail 77 attached to the rod 74, the end of the tail is inserted into the window 200 and fixed on the hook tape 201 on the clamp.

[0348] The protective function in the joint/connection is performed by the upper section of the clamp on the rod and by attaching the clamp to the hook tape 201.

[0349] The bridge 89 can be installed on the part 90 after pre-assembly with the rod 74. This joint/connection increases the complexity of disassembly when the end of the clamp does not protrude from the window 200.

[0350] FIG. 42 show embodiments for attaching rods with different cross-sectional profiles to the bridge. The rods are shown with a piece of hook and loop fastener 204 installed on them, such as a loop tape for example.

Mechanical Characteristics of Hook and Loop Elements and Connection Sizes.

[0351] Previously, the interaction processes of hook and loop fastener elements were considered from a qualitative point of view (FIGS. 9, 10, 11). But to calculate hook and loop fastener connections when used as structural elements of machine parts, knowledge of the mechanical characteristics of hook and loop fastener and its parts is required. In order to obtain such characteristics, four testing mechanisms or stands were created: two stands for measuring hook and loop fastener characteristics and testing flat assemblies (FIGS. 45, 47) and two mechanisms/stands for testing flanged and end couplings (FIGS. 50, 53).

Flat Connections Characteristics

[0352] Referring now to FIG. 45 illustrating an apparatus for compression of hook and loop fasteners including parts thereof. The apparatus consists of first posts 311 and second post 314 supported by the base 301. On the left post, on a pin 307, there are two levers 308 provided spaced from each other, covering both posts at front and rear. Both levers 308 are connected to the first post 311 by a pin 307. A compression unit provided between the posts and levers consists of lower plate 302 and upper plate 310 connected by two ties 309. The lower plate 302 attached to the base 301 is adapted to receive/support a hook and loop fastener sample 317.

[0353] A dial indicator 312 is installed at a central area of the upper plate 310. The contact point of the indicator engages an adapter 306 situated in a space between the levers 308 and attached to the levers by a pin 315. A self-aligning pressure unit 316 is installed on the lower part of the adapter 306, through which the hook and loop fastener sample 317 is compressed.

[0354] A dynamometer 313 is attached to the free ends of the levers 308, which by means of a power unit (not shown in the figure) applies pressure to the hook and loop fastener sample 317. The dynamometer 313 reflects the value of the applied pressure/force P, and the dial indicator 312 shows the value of the hook and loop fastener sample 317 compression.

[0355] The hook and loop fastener samples including parts thereof such as hook tape and loop tape are tested in the apparatus 300. The applicable dimensions of the sample are as follows: width B.sub.0 and length L.sub.0, for example. 11 inch, with contact area hooks and loops .sub.0. The .sub.0 value is typically less than 1 square inch because the hook and loop stripes do not extend to the side edges of the respective tapes.

[0356] FIG. 46 is a graph illustrating relation between the thickness S of hook and loop fastener and its parts and the compressive force N. The compression data is used to calculate the value of the compressive force generated by the force/power element of the power unit. This is applicable to the spring (FIG. 13), and the hook and loop fastener compression force in the end sleeve (FIGS. 35, 55).

[0357] B. Referring now to FIG. 47 illustrating apparatus for stretching individual/unitary hook and loop fastener connections.

[0358] The apparatus for stretching individual/unitary hook and loop fastener connections (FIG. 8a) mainly consists of the apparatus 300 for compression of hook and loop fasteners (FIG. 45), with the following additional elements. Instead of the hook and loop fastener sample 317, a clamp 303 is installed on the lower plate 302, a clamp 305 is attached to the upper plate 310, a unitary connection 304 is fixed in the clamps. A unitary joint 304 is stretched in the apparatus. Therefore, the force P is applied to the levers 308 through the bearing assembly 321, which is fixed on the beam 320.

The stretching apparatus can be used for testing flat units (see FIGS. 26, 27, 28).

[0359] FIG. 48 is a chart illustrating relation between the elongation L of individual hook and loop fastener joints and the tensile/stretching force P applied at various value of the compression force in the compressor.

[0360] The value S on the right side of the curves is the hook and loop fastener thickness in the compression device, and it varies between minimum (curve a) and maximum (curve e) compression values. Compression is carried out by a compressor (FIG. 13c), the change in the value of compression is provided using thin liners installed in the window of the compressor.

[0361] C. An example of calculating/determining a flat unit having a compressor/squeezer (FIGS. 26, 27, 28).

[0362] Initial data: [0363] the parameter of an individual connectionthe area of the contact zone .sub.0; [0364] the connection has a compressor/squeezer; [0365] thickness of an unitary/individual connection S=S.sub.A: it is determined by the thickness of the hook and loop fastener compressed in the compressor/squeezer; point A is selected in FIG. 46; change in the elongation of a unitary connection from the tensile force P occurs along the curve c (FIG. 48); [0366] elongation of a unitary/individual joint L.sub.B=1 mm; it corresponds to point B and tensile/stretching force P.sub.B (FIG. 48); [0367] connection width B=1 inch; [0368] the connection must transmit the tensile force P*.

[0369] The dimensions of the connection are determined in the following manner:

[0370] 1. Determine the coefficient k of exceeding the specified value of the tensile force P* over the force P.sub.B of a unitary/individual connection having the length of 1 inch:

[00007]$k=P^{*}/P_B.$

[0371] 2. The area of the required contact area of the hook tape and loop tape parts is equal to

[00008]${}^{*}=k{}_0.$

[0372] 3. Since the width B of 1 inch connection is equal to the width of a unitary/individual connection B.sub.0, the connection length will be

[00009]$L^{*}=k\mathrm{inches}.$

[0373] 4. If the obtained value of L* is not satisfactory/enough; then, for example, it is possible to reduce it by half, to obtain a flat unit having the length of L* by means two individual units connected in parallel (FIG. 49).

[0374] 5. Determine the compression force N to calculate compression elements, for example, springs.

[0375] Based on the thickness of the compressed unitary/individual joint S.sub.A (FIG. 46, point A), the value of the compression force N.sub.A is determined. Taking into account the coefficient k, we have:

[00010]$N=k{N}_A.$

[0376] In a flat unit, the compression force does not depend on the number of individual joints and each of them is compressed to a thickness S=S.sub.A by the same force.

[0377] A. Referring now to FIG. 50 illustrating an apparatus for testing flange couplings (FIG. 50). The apparatus consists of a base 333 supporting a stand 334 formed with a bushing 335 through which the coupling shaft 332 passes. A holder 336 for the right half coupling with a right coupling 348 are disposed on the left side of the shaft. The holder 336 is fixed on the shaft by a clamp 347. At the left end of the shaft there are mounted the left half of the coupling 349 with connected holder 350. The half-coupling 349 is installed directly at the half-coupling 348, on the other hand a small gap can be provided therebetween.

[0378] Identical hook and loop fastener parts 343 and 344 (the loop tape, for example) are attached to the outer cylindrical surfaces of the coupling halves. After installation of the half couplings on the shaft, a wide strip of the hook and loop fastener 337 counterpart (in this instance hook tape) is applied over both loop tape sections.

[0379] At the right end of the coupling shaft, a pulley 331 with a flexible connector 345 is installed. The flexible connector 345 can be a braid for example. The connector 345 through the dynamometer 346 is connected to a power device that generates a force Q) on the shaft 332 resulted in the torque M (the power device is not shown).

[0380] The Dial Indicator holder 342 and the Dial Indicator 341 are fixed to the holder 350. The contact point of the indicator 341 rests against the mounting surface 340 on the holder 336 of the right half coupling. The mounting surface 340 is at the level of the coupling shaft axis.

[0381] After the coupling is assembled, the holder 350 of the left half coupling is fixed on the base 333 by an angle 339 and a screw 338. Dynamometer 346 shows the value of the force Q, and the Dial Indicator 341 shows the value of the angle of the relative rotation of the half-couplings.

[0382] Referring now to FIG. 51 which is a chart showing relationship between the angle of relative rotation of the halve coupling of the flange coupling and the torque momentum M.

[0383] When coupling is tested without a clamp (curve 1), the hook tape 337 (FIG. 50) has the protection shown in FIG. 20e. When tests are conducted with a clamp (curve 2); two screw clamps were used as a clamp. Before installation the clamps were adjusted to the required diameter according to a template and marked in this position (FIG. 18, windows 52, 54).

[0384] B. An example of calculating a flange coupling (FIG. 34).

Available Data:

[0385] coupling dimensions; [0386] D is the diameter of the coupling:*

[0387] (*) hook and loop fastener is attached to the outer surfaces of the flanges, so the diameter over which the torque is transmitted passes over the hook and loop fastener inner layer 18 (FIG. 6); we assume that it passes in the middle of the hook and loop fastener thickness; in this instance the diameter D* is larger than the diameter of the coupling flanges by the thickness S:

[00011]$D^{*}=D+S,\mathrm{mm}.$

[0388] The thickness S is assumed to be constant; [0389] B is the width of the half-coupling flange; [0390] hook and loop fastener connection width on flanges

[00012]$B=1\mathrm{inch}.$ [0391] in the calculation, the parameters of an individual connection are accepted as in the case of a flat unit

[0392] (FIG. 49); B.sub.0=L.sub.0=1 inch and .sub.0.

[0393] It is required to determine the maximum torque momentum M for the given coupling dimensions.

[0394] 1. Determine the perimeter of the hook and loop fastener contact zone L=D* and the number of individual connections the length of 1 inch that fits into the perimeter of the diameter D *:

[00013]$k=L/1\mathrm{inch}.$

[0395] 2. Determine the required area of the hook and loop fastener contact zone of one half-coupling:

[00014]$=k{}_0.$

[0396] We use half the width of a 2B Hook Tape for each half-coupling.

[0397] 3. Knowing the thickness S.sub.A of the compressed hook and loop fastener of a unitary joint with elongation of the joint, for example, L.sub.B=1 mm at point B (FIG. 48), the tensile force P.sub.B is determined;

[0398] 4. Torque transmitted by the half-coupling:

[00015]$M=P{D}^{*}/2,$ [0399] where P=k P.sub.B.

[0400] 5. Angle of relative rotation of half-couplings

[00016]$=3601/\left(D\right){[}^0],$ [0401] where the value of the linear displacement I of the half-couplings tangentially disposed to the outer diameter D of the flanges is the sum of l=l.sub.1+l.sub.2+l.sub.3 (FIG. 52).

[0402] Referring now to FIG. 52 illustrating an embodiment of a flange coupling, in which the diameter of the shafts is equal to the outer diameter of the flanges. This coupling is considered to be a sleeve coupling. Processes taking place in hook and loop fastener are the same for both types of couplings. The shafts are installed with a gap G, and the distance between the strips of loops 372 on their bases 370 at the ends of the shafts is H.

[0403] l.sub.1=l.sub.2hook and loop fastener deformations over the half-couplings, l.sub.3deformation of the upper part of the book and loop fastener over the joint of the half-couplings, in this example, it is hook tape. If measures are taken to increase the rigidity of the hook tape over the joint and take l.sub.3=0, as well as l.sub.1=l.sub.2=L.sub.B, then it is possible to approximately determine the angle of rotation .

[0404] The actual angle of rotation is determined in the process of testing the coupling, after which the assumptions adopted in the calculation are refined.

Example of the End Sleeves Application Characteristics

[0405] A. Referring now to FIG. 53 illustrating an apparatus for testing end couplings.

[0406] The apparatus for testing the end couplings differs from the apparatus for testing the flange couplings (FIG. 50) by the location of the hook and loop fastener parts on the half-couplings (they are located at the end surfaces) and by the presence of book and loop fastener compressive devices. Such devises include a thrust ball bearing 357 fixed on the rack 334, and a device that compresses the hook and loop fastener 360 through the push rod 356 by force N through the dynamometer 355. The device for compressing the hook and loop fastener is not shown.

[0407] The holder 350 of the left half-coupling is fastened to the base 333 by an angle 339 and a screw 338 after the hook and loop fastener 360 has been compressed. Dial Indicator 355 shows the amount of force of compression N of hook and loop fastener in the coupling.

[0408] FIG. 54 is a chart showing the relationship of the angle of relative rotation of the half-couplings of the end coupling and the applicable torque momentum M.

[0409] B. An example of calculation of an end coupling (FIG. 35).

Available Data:

[0410] coupling dimensions (FIG. 55): D.sub.1; D.sub.2; m; [0411] D.sub.3=D.sub.1(m/2)2. Assuming that the width m of the hook and loop fastener is small and that the resulting force P is applied in the middle of the ring; [0412] hook and loop fastener compression is performed by a spring until the thickness S=S.sub.B (FIG. 48, point B) is reached; at this point the force P.sub.B is transmitted.

[0413] It is required to determine the maximum torque momentum M.

[0414] 1. The area of the contact zone hook and loop fastener and the coefficient k1 of the excess of the area of the contact zone in the coupling over an individual connection:

[00017]$k_1=/{}_0$

[0415] It follows from the above that the resulting force P in the coupling is equivalent to k.sub.1 individual connections and the force P=k.sub.1 P*.sub.0, where P*.sub.0=P.sub.B is the force transmitted by the individual connection.

[0416] 2. Torque created by force P in the coupling:

[00018]$M=P{D}_3/2.$

[0417] 2. To compress an individual hook and loop fastener connection on the compression apparatus (FIGS. 45, 46, point A) to the thickness S=S.sub.A, force N.sub.A is required. As a result, the hook and loop fastener compression force in the coupling will be N*=k.sub.1N.sub.A. This value is used to calculate the spring.

[0418] 3. Angle of relative rotation of half-couplings

[00019]$=360L_B/\left(D_1\right){[}^0],$ [0419] where the value of the linear displacement of the half-couplings tangentially to the outer diameter D of the flanges is assumed to be equal in the first approximation to L.sub.B. The actual angle of rotation is determined in the process of testing the coupling, after which the assumptions adopted in the calculation are refined.