Abstract
An orthopedic device for limiting the movement of a joint arranged between a first and a second body region. The orthopedic device comprises at least a receptacle that can be fastened to the first body region and a pull-out body that can be fastened to the second body region and can be moved in relation to the receptacle, wherein a passage cross-section filled with a dilatant fluid is provided perpendicularly to a pull-out direction between the receptacle and the pull-out body, wherein at least one passage-limiting element is provided for changing the passage cross-section.
Claims
1. An orthopedic device for limiting the movement of a joint disposed between a first body portion and a second body portion, comprising at least one reception fixable to the first body portion, and a pull-out body fixable to the second body portion and movable relative to the reception, wherein perpendicular to a pull out direction between the reception and the pull-out body a passage cross section filled with a shear thickening fluid is provided, and wherein at least one passage limiting element for changing the passage cross section is provided.
2. The orthopedic device according to claim 1, wherein the at least one passage limiting element is at least one of plate shaped, disc shaped, and rod shaped.
3. The orthopedic device according to claim 1, wherein the at least one passage limiting element is flexible and on a first end firmly, preferably in a torque proof manner, connected to one of the pull-out body and the reception, in order to deflect from a starting position.
4. The orthopedic device according to claim 1, wherein the at least one passage limiting element on a first end is connected to one of the pull-out body and the reception by means of a joint, preferably a hinge, and more preferably a film hinge, in order to deflect from a starting position.
5. The orthopedic device according to claim 1, wherein the at least one passage limiting element is disposed in an acute angle to one of the pull-out body and the reception in a starting position.
6. The orthopedic device according to claim 1, wherein the pull-out body is surrounded by at least one umbrella shaped passage limiting element.
7. The orthopedic device according to claim 1, wherein at least one of the pull-out body and the reception have at least one recess in which at least one passage limiting element is recessed in a starting position.
8. The orthopedic device according to claim 1, wherein the pull-out body has at least one passage for providing an additional flow path for the shear thickening fluid, in which at least one passage limiting element is recessed in a starting position.
9. The orthopedic device according to claim 7, wherein the at least one passage limiting element has at least one protrusion protruding into the passage cross-section for the activation of a deflection of the at least one passage limiting element.
10. The orthopedic device according to claim 1, wherein the at least one passage limiting element has a pouch in order to redirect a part of the shear thickening fluid into a passage of the pull-out body, wherein a pouch opening points in the direction of the movement of the pull-out body, preferably in the pull-out direction of the pull-out body.
11. The orthopedic device according to claim 1, wherein between the reception and the pull-out body a flexible membrane is provided in parallel to the pull-out direction, wherein the membrane has an inlet opening in the area of a second end of the reception for receiving the shear thickening fluid, and an outlet opening in the area of a first end of the reception for letting out the shear thickening fluid, wherein the membrane divides the inside of the reception into a first chamber for receiving the pull-out body and a second chamber, wherein a stripper is disposed in front of the inlet opening in order to lead the shear thickening fluid from the first chamber through the inlet opening into the second chamber.
12. The orthopedic device according to claim 1, wherein the reception is flexible.
13. The orthopedic device according to claim 1, wherein the reception comprises a weaving structure, preferably a pulling grip, which encloses a reception body.
14. The orthopedic device according to claim 1, wherein a pulling grip for closing the reception filled with the shear thickening fluid is disposed between the reception and the pull-out body, wherein a first end of the pulling grip is circumferentially attached to an upper section of the pull-out body, and a second end of the pulling grip is circumferentially attached to an opening edge of the reception.
15. The orthopedic device according to claim 1, wherein the at least one passage limiting element is a torsion body which is twistable around the longitudinal axis of the at least one passage limiting element from a starting position to a limiting position and from the limiting position to the starting position, wherein in the starting position a narrow side of the at least passage limiting element points into a pull-out direction and in a limiting position a broad side of the at least one passage limiting element points into the pull-out direction.
16. The orthopedic device according to claim 1, wherein the reception has an elastic balancing membrane in at least one area, which can balance a change of volume within the reception caused by a movement of the pull-out body.
17. The orthopedic device according to claim 1, wherein the distance between the pull-out body and the reception perpendicular to the pull-out direction in the starting position amounts between 0.01 to 1000 mm, preferably 0.1 to 50 mm, and more preferably 0.1 to 15 mm and even more preferably 0.1 to 5 mm.
18. The orthopedic device according to claim 1, wherein the at least one passage limiting element comprises one of natural rubber and plastic, preferably one of silicon and thermoplastic resin, more preferably at least one of polypropylene, polyethylene and polyurethane.
19. The orthopedic device according to claim 1, wherein the shear thickening fluid comprises a dispersion of one of ethylenglycol and silicone oil and siliciumdioxid, preferably silica gel with a particle size of 2 to 1000 nm, surfaces of 30 to 250 m.sup.2/g, and a solid content of 5 to 80 weight-% and stabilizers.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0090] Further embodiments and aspects of the present device are explained by means of the following description of the figures in more detail.
[0091] FIG. 1 shows a schematic side view of a cross-section through an orthopedic device in a starting position;
[0092] FIG. 2 shows a schematic cross-section side view of the orthopedic device in a position differing from the starting position;
[0093] FIG. 3a shows a schematic cross-sectional top view of the orthopedic device of FIG. 2;
[0094] FIG. 3b shows a schematic cross-sectional top view of the orthopedic device of FIG. 3b;
[0095] FIG. 4 shows a schematic cross-sectional detailed view of a pull-out body comprising a recess;
[0096] FIG. 5 shows a cross-sectional side view of an orthopedic device with a pull-out body in a starting position comprising a passage;
[0097] FIG. 6 schematically shows a cross-sectional side view of the orthopedic device of FIG. 5 in a position differing from the starting position;
[0098] FIG. 7 schematically shows a front view of a pull-out body with passages and passage limiting elements disposed therein;
[0099] FIG. 8 schematically shows a cross-sectional side view of an orthopedic device with a pull-out body in a starting position according to FIG. 5 with a protrusion on the passage limiting element;
[0100] FIG. 9 schematically shows a cross-sectional side view of the orthopedic device according to FIG. 7 with a passage limiting element having a protrusion;
[0101] FIG. 10 schematically shows a cross-sectional side view of an orthopedic device in a starting position with an anchor-shaped passage limiting element;
[0102] FIG. 11 schematically shows a cross-sectional side view of the orthopedic device according to FIG. 10 in a position differing from the starting position;
[0103] FIG. 12a schematically shows a cross-sectional front view of an orthopedic device in a starting position with a passage limiting element in the form of a torsion body;
[0104] FIG. 12b schematically shows a cross-sectional top view of the orthopedic device according to FIG. 12a;
[0105] FIG. 13a schematically shows a cross-sectional front view of the orthopedic device according to FIG. 12a in a position differing from the starting position;
[0106] FIG. 13b schematically shows a cross-sectional top view of the orthopedic device according to FIG. 13a;
[0107] FIG. 14 schematically shows a cross-sectional side view of an orthopedic device in the starting position with a passage limiting element in the form of a pouch;
[0108] FIG. 15 schematically shows a cross-sectional side view of the orthopedic device according to FIG. 14 in a position differing from the starting position;
[0109] FIG. 16 schematically shows a cross-sectional side view of an orthopedic device in a starting position with a membrane;
[0110] FIG. 17 schematically shows a cross-sectional side view of the orthopedic device according to FIG. 16 in a position differing from the starting position;
[0111] FIG. 18 schematically shows a cross-sectional side view of an orthopedic device in a starting position with a balancing membrane at the end of the reception;
[0112] FIG. 19 schematically shows a cross-sectional side view of an orthopedic device with a balancing membrane at the end of the reception in a position differing from the starting position;
[0113] FIG. 20a schematically shows a cross-sectional front view of an orthopedic device in a starting position with a passage limiting element in the form of a shield;
[0114] FIG. 20b schematically shows a cross-sectional top view of the orthopedic device according to FIG. 20a;
[0115] FIG. 21a schematically shows a cross-sectional front view of the orthopedic device according to FIG. 20a in a position differing from the starting position;
[0116] FIG. 21b schematically shows a cross-sectional top view of the orthopedic device according to FIG. 21a;
[0117] FIG. 22 schematically shows a diagram of the development of the viscosity over the related shear rate with respect to different passage cross-sections, respectively;
[0118] FIG. 23 schematically shows an ankle joint orthosis with an orthopedic device; and
[0119] FIG. 24 schematically shows a wrist orthosis with an orthopedic device.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0120] Hereafter preferred embodiments are described by means of the figures. Thereby, the same elements, similar elements or elements with the same effect are indicated by identical reference numerals. To avoid redundancies the following description partially goes without a repeated description of these elements.
[0121] FIG. 1 schematically shows an orthopedic device 1 for limiting the movement of a joint disposed between a first and a second body portion. The device 1 comprises a reception 2 filled with a shear thickening fluid, which can be fixed to a first body portion, and a pull-out body 3, which can be fixed to a second body portion and is movable relatively to the reception 2 in a pull-out direction A and partially extends to the inside of the reception 2 so that between the reception 2 and the pull-out body 3 a passage cross-section filled with the shear thickening fluid is provided.
[0122] In the present case, the pull-out body 3 is made of polyamide and the reception 2 is made of polyurethane. Alternatively, both parts can be made of different plastics, such as silicone, rubber, or of a thermoplastic material, such as polyamide, polypropylene, polyethylene or polyurethane. In particular, in terms of the reception 2 it is important that the used material is fluid impermeable.
[0123] In the embodiment shown in FIG. 1 the pull-out body 3 has a passage limiting element 6, 6 on each of a front side 30 and a back side 31. The passage limiting element 6, 6 has a first surface 63, 3 which faces the pull-out body surface, and a second surface 64, 64, which faces the inner surface 20 of the reception 2. Furthermore, the passage limiting element 6, 6 comprises a first end 61, 61, which is connected with the pull-out body 3, and a second end 62, 62, which is free standing and points into the direction of the pull-out direction A. In FIG. 1 the passage limiting element 6, 6 is connected to the pull-out body 3 on its first end 61, 61 via a joint 66, 66, here in the form of a film joint. In this case, the film joint is provided as a local reduction of the wall thickness of the passage limiting element 6, 6. Thus, the bending stiffness of the passage limiting element 6, 6 in the area of the film joint is reduced. Thus, the passage limiting element 6, 6 is disposed in a manner foldable around the joint 66, 66, in this case the film joint, relative to the pull-out body 3.
[0124] In the starting position the passage limiting element 6, 6 is aligned parallel to the pull-out body 3, hence, in pull-out direction A. The two passage limiting elements 6, 6 are attached at the same height on the pull-out body 3 with respect to the pull-out direction A. Thus, when the pull-out body 3 is pulled out of the reception 2, on the front side 30 and the back side 31 of the pull-out body 3 symmetrical flow conditions of the shear thickening fluid or a symmetrical fluid flow F relative to the pull-out body 3 and, thus, a symmetrical load distribution within the orthopedic device 1 is created. Alternatively, the passage limiting elements 6, 6 can also be disposed in an offset manner.
[0125] The passage limiting element 6, 6 in FIG. 1 is configured in a way that even at a deflection of 90 degree to the pull-out direction A it does not contact the inner surface 20 of the reception 2. The bending stresses created in the film joint when the passage limiting element 6, 6 is deflected, cause the passage limiting element 6, 6 to return itself to the load-free state. Due to the configuration of the film joint it is not possible for the passage limiting element 6, 6 to take-up an angle greater than 90 degrees to the pull-out direction A. Thus, a stop at the joint 66, 66 for limiting the movement of the passage limiting element 6, 6 can be provided. Also, a means for returning the passage limiting element 6, 6 or for increasing the reflection resistance around the joint 66, 66, such as a bending spring, can be provided. In a further alternative the passage limiting element 6, 6 can be configured in a way that the second end 62, 62 contacts the inner surface 20 of the reception 2 at a maximum deflection and, thus, defines the maximum angle of the deflection of the passage limiting element 6, 6.
[0126] In an alternative embodiment the passage limiting element 6, 6 can also be connected directly to the pull-out body 3 without a joint connection. Alternatively, the pull-out body 3 can also include several passage limiting elements 6, 6 on its front side 30 and its back side 31, which at least in a section of the pull-out body 3 are regularly disposed. The pull-out body 3 has the same number of passage limiting elements 6, 6 on the front side 30 and the back side 31. In the present case, the passage limiting element 6, 6 is of the same material as the pull-out body 3. Alternatively, the passage limiting element 6, 6 can also be of a different material, preferably a different thermoplastic resin and be connected to the pull-out body 3 by means of a multi-component manufacturing process.
[0127] In the embodiment of the orthopedic device 1 shown in FIG. 1 the pull-out body 3 is movably held in the reception 2 in a rail guide, not shown. The pull-out body 3 can retract into or extend from the reception 2 in the pull-out direction A. Alternatively the pull-out body 3 can also have spacers in the form of local protrusions in order to guide the pull-out body 3 through the reception 2 in a defined manner.
[0128] In the embodiment shown in FIG. 1 the orthopedic device 1 has returning means 5 for the pull-out body 3, which after a movement of the pull-out body 3 out of the starting position into a position differing from the starting position moves the pull-out body 3 back into the starting position. Depending on the physiological conditions of the joint disposed between the first body portion and the second body portion, the returning means 5 can be necessary in order to return the joint after being deflected into a resting position. The returning means 5 is chosen in a way that the joint undergoes a gentle reset or that the pull-out body 3 is moved through the shear thickening fluid so that no substantial rise of the viscosity in the shear thickening fluid is induced. Alternatively, the returning means 5 can also be configured in a way that it is solely provided for the reset of the pull-out body 3 into the starting position and does not influence the position of the joint. In this case the return means 5 enables that the pull-out body 3 which, for example, underwent a change of position in a position differing from the starting position, in particular about an offset in the pull-out direction A, by means of an elongation of the joint, also returns in its starting position after a reset of the joint in its resting position.
[0129] The return means 5 shown in FIG. 1 is an elastic plastic in the form of a rubber band with the aforementioned properties. Alternatively, the return means 5 can also be formed by a spring, by a pair of permanent magnets, wherein one permanent magnet is disposed at the lower end of the reception 2 and the other permanent magnet is disposed at the end of the pull-out body 3 facing the lower end of the reception 2, or by an elastic sealing. Furthermore, the reset of the pull-out body 3 can also be caused by a negative pressure present in the reception 2. The negative pressure is created when the pull-out body 3 is pulled out along the pull-out direction A.
[0130] Furthermore, FIG. 1 schematically shows a sealing 12 which is disposed on the upper end of the reception 2, which is open to the outer vicinity, and seals the inside of the reception 2 against the outer vicinity. The sealing 12 runs around the front side 30, the back side 31 and the lateral surfaces 32 and 32 (see FIG. 3) of the pull-out body 3. The pull-out body 3 can be moved relatively to the sealing 12. A circumferential sealing lip of the sealing 12 prevents the shear thickening fluid from leaking out of the inside of the reception 2. In the present case the sealing is formed of thermoplastic polyurethane, alternatively, the sealing can be formed of a different plastic such as latex.
[0131] Alternatively, the sealing 12 can be formed like a bellows. A first end of the sealing bellows is firmly connected with the reception 2 and a second end of the sealing bellows is firmly connected with the pull-out body 3. When the pull-out body 3 moves out of the reception 2 the distance between the first and the second end of the sealing bellows increases. Accordingly, the sealing bellows follows the movement of the orthopedic device 1 or the pull-out body 3.
[0132] Furthermore, a sealing bellows additionally can provide the function of the return means. In this case, the bellows body of the sealing 12 has an elasticity which enables returning to a resting position after a deflection of the orthopedic device 1, wherein the first end and the second end of the sealing bellows approach each other. An elastic rubber is used as sealing material.
[0133] When the pull-out body 3 is moved into or out of the reception 2 the movement of the pull-out body 3 is affected by the properties of the shear thickening fluid. A movement of the pull-out body 3 relative to the reception 2 creates an initiation of a shear force into the shear thickening fluid due to the side adhesion between the shear thickening fluid and the pull-out body surfaces 30, 31 or the inner surface 20 of the reception 2. Due to the viscosity of the shear thickening fluid a force in the direction of the pull-out direction A can be transferred from the pull-out body 3 to the reception via the shear of the shear thickening fluid. The amount of the forces to be transferred depends on the speed of the pull-out body 3 relative to the reception 2 and to a high degree on the passage cross-section.
[0134] When under a low force impact or with a physiological speed the orthopedic device 1 retracts or extends, due to the low viscosity of the shear thickening fluid only a low shear force generation occurs. Thus, the pull-out body 3 can easily be moved in the shear thickening fluid.
[0135] In case of a pull-out movement the shear thickening fluid flows around the passage limiting elements 6, 6 which are configured in a way that due to the forces caused by the flow acting on the passage limiting elements 6, 6 at physiological pull-out speeds they do not or only to a little degree move out of their starting position. The position of the passage limiting elements 6, 6 substantially corresponds to the starting position.
[0136] FIG. 2 shows the orthopedic device 1 of FIG. 1 in a position differing from the starting position. With respect to the starting position the passage limiting element 6, 6 is deflected around the joint 66, 66 in the direction of the inner surface 20 of the reception 2. Thus, the second end 62, 62 of the passage limiting element 6, 6 is closer to the inner wall of the reception compared to the starting position. Thereby, the passage cross-section in the area of the passage limiting element 6, 6 is reduced compared to the starting position. Accordingly, the shear rate of the shear thickening fluid compared to the shear rate of the shear thickening fluid in the starting position is substantially higher in the area of the passage limiting element 6, 6, leading to an increase of the viscosity of the shear thickening fluid in these areas when the pull-out body 3 is moved in pull-out direction A, and, thus, the resulting shear rates in the shear thickening fluid are substantially higher compared to the non-deflected passage limiting element 6, 6.
[0137] The deflection of the passage limiting elements 6, 6 occurs at pull-out speeds above the physiological area due to the flow dynamic pressure forces acting on the passage limiting elements 6, 6 caused by the flow resistance of the passage limiting elements 6, 6 in the shear thickening fluid. Due to their geometry the passage limiting elements 6, 6 are folded around the joints 66, 66 in the direction of the inner surface 20 of the reception 2.
[0138] The higher the forces acting on the orthopedic device 1 or the higher the speeds, which extend or retract the reception 2 and the pull-out body 3 with respect to each other, the higher are the shear rates occurring between the pull-out body 2 and the shear thickening fluid. With the increase of the shear rates also the viscosity of the shear thickening fluid rises. The shear thickening fluid has a discrete jump in dilatancy at which a rapid, significant increase of the viscosity can be registered. In terms of a high viscosity present in the shear thickening fluid, in particular beyond the jump in dilatancy, the reception 2 and the pull-out body 3 of the orthopedic device 1 cannot or only slightly be moved with respect to each other or for a further movement particularly high forces are required.
[0139] When the passage limiting elements 6, 6 are in the deflected position the shear rate of the shear thickening fluid in the area of the passage limiting elements 6, 6 at unphysiological pull-out speeds is above the critical shear rate at which the jump in dilatancy occurs. This requires a particularly high viscosity of the shear thickening fluid whereby, a high degree of force transfer between the pull-out body 3 and the reception 2 is generated and a high retention force occurs which acts against a pull-out force responsible for the pull-out of the pull-out body 3. The movement of the pull-out body 3 and, thus, the movement of the first and the second body portion between which the orthopedic device 1 is disposed is slowed down or completely impeded.
[0140] Compared to the starting position the unfolded passage limiting elements 6, 6 cause an increase of turbulences and whirlings W in the shear thickening fluid due to the stronger redirection of the shear thickening fluid and the higher flow resistance of the passage limiting elements 6, 6. This also leads to an increase of the retention force described above.
[0141] In an alternative embodiment of the orthopedic device instead on the pull-out body the passage limiting elements can also be provided on the inner surface of the reception. Here, the orientation of the passage limiting elements with respect to the pull-out direction is reversed. In other words, the second end points contrary to the pull-out direction. Alternatively, the passage limiting elements can be provided on one side of the pull-out body, for example the front side, and the second side, here the back side accordingly, can be realized without passage limiting elements. The part of the inner surface of the reception which faces the second side, here the back side accordingly, one or a plurality of passage limiting elements can be provided. A combination of passage limiting elements on the inner surface of the reception and the pull-out body is also possible.
[0142] FIG. 3a schematically shows a cross-sectional top view of the orthopedic device 1 of FIG. 1. The passage limiting elements 6, 6 are present on the front side 30 as well as on the back side 31 of the pull-out body 3 in the starting position and, thus, in a folded state. The front side 30 and the back side 31 of the pull-out body 3 are many times larger than both the lateral surfaces 32, 32 of the pull-out body 3. Thus, the front side 30 and the back side 31 and the passage limiting elements 6, 6 present thereon are responsible for the majority of the shear force transfer from the pull-out body 3 to the shear thickening fluid.
[0143] In comparison FIG. 3b schematically shows a cross-sectional top view of the orthopedic device 1 of FIG. 2. The strongly reduced passage cross-section due to the unfolded position of the passage limiting elements 6 can be significantly recognized. Furthermore, due to the unfolded position of the passage limiting elements 6 the pull-out resistance in pull-out direction A is increased due to the increased projected area of the passage limiting elements 6. When the pull-out body 3 is moved into the pull-out direction the shear thickening fluid experiences a stronger redirection. Furthermore, more turbulences and whirlings W are created.
[0144] FIG. 4 schematically shows a cross-sectional detailed view of a pull-out body 3 having a recess 36. The first surface 63 of the passage limiting element 6 has a distance to an inner surface 37 of the recess 36 so that during the pull-out movement the shear thickening fluid flows around the first surface 63 of the passage limiting element 6 and, thus, can cause a deflection of the passage limiting element 6 at unphysiological pull-out speeds. In the case of a pull-out body 3 having a plurality of recesses 36 the recesses 36 of the pull-out body 3 with a passage limiting element 6 contained therein can be provided according to the pull-out body 3 of FIGS. 1 and 2, preferably also on the front side 30 and the back side 31 of the pull-out body 3. By means of recessing the passage limiting elements 6 in the recess 36 the total distance of the pull-out body 3 to the reception perpendicular to the pull-out direction A can be used as passage cross-section for the shear thickening fluid. By means of a force impact onto the orthopedic device 1 uncritical for the joint to be preserved, the pull-out body 3 and the reception can be moved relatively towards each other, wherein the passage cross-section is not influenced or reduced by the passage limiting elements 6.
[0145] FIG. 5 schematically shows a cross-sectional side view of an alternative embodiment of an orthopedic device in a starting position. The pull-out body 3 has passages 34, 34, which completely pass through the pull-out body 3 from the front side 30 to the back side 31. The passage limiting elements 6, 6 are disposed in the passages 34, 34 of the pull-out body 3 and are connected to the pull-out body 3 by means of joints 66, 66. The passage limiting elements 6, 6 are configured in parallel to the pull-out direction A, thus, no local reduction of the passage cross-section occurs as it is the case in the configuration of the passage limiting elements 6, 6 in FIG. 1. Overall, little component heights of the orthopedic device 1 can be realized. No additional gap is needed between the pull-out body 3 and the reception 2 in order to provide the passage limiting elements 6, 6. Due to the low flow redirection of the fluid flow F when the pull-out body 3 having passage limiting elements 6, 6 with this geometry is moved, less viscosity increasing turbulences and whirlings W occur. This enables a high ease of operation of the movement of the pull-out body 3 in pull-out direction A.
[0146] In the present embodiment the passage limiting elements 6, 6 are disposed centrally in the passages 34, 34. As the wall thickness of the passage limiting elements 6, 6 is lower than the one of the pull-out body 3, the first surface 63, 63 or the second surface 64, 64 of the passage limiting elements 6, 6 are offsetted to the inside with respect to the front side 30 or the back side 31, respectively. The material slots for realizing the film joints of the passage limiting elements 6, 6 are disposed alternatingly with respect to the central axis of the pull-out body 3 so that the passage limiting elements 6, 6 each are deflected in the direction of the front side 30 and the back side 31 of the pull-out body 3, respectively, in terms of unphysiological pull-out speeds. On the one hand an even load distribution on the pull-out body 3 can be achieved. On the other hand the positive effect for reducing the passage cross-section of the fluid achieved by the passage limiting elements 6, 6 can be used on both sides of the pull-out body 3.
[0147] In an alternated embodiment the passage limiting elements 6, 6 can also align with the surface of the pull-out body 3 which lies in the folding direction of the respective passage limiting element 6, 6 or can protrude there from. The passage limiting elements 6, 6 can also have the same or a higher wall thickness than the pull-out body 3 and also be disposed eccentrically in the passage 34, 34. Furthermore, instead of the connection by means of a joint 66, 66 also a rigid connection between the passage limiting elements 6, 6 and the pull-out body 3 can be provided.
[0148] FIG. 6 shows the orthopedic device 1 of FIG. 5 in a position differing from the starting position. The passage limiting elements 6, 6 are deflected in the direction of the inner surface 20 of the reception 2. The passage cross-section between the inner surface 20 and the reception 2 and the corresponding second end 62, 62 of the passage limiting elements 6, 6 is reduced compared to the starting position. Due to the deflection of the passage limiting elements 6, 6 in the passages 34, 34 of the pull-out body 3 the passages 34, 34 are open. In terms of a movement of the pull-out body 3 fluid can flow through the passages 34, 34. Thus, in terms of a movement of the pull-out body 3 the fluid flow F of the shear thickening fluid is divided in a way that a first part of the shear thickening fluid flows through the passage cross-section and a second part of the shear thickening fluid flows through the passage 34, 34 of the pull-out body 3. Compared to the flow path of the flow through the passage cross-section in the starting position in both the flow paths of the flow of the shear thickening fluid a higher shear rate is present so that the shear thickening fluid has an increased viscosity in both divided flow paths.
[0149] In order to facilitate the deflection of the passage limiting elements 6, 6 the geometry of the passages 34, 34 and the passage limiting elements 6, 6 is configured in a way that when the pull-out body 3 is moved in pull-out direction A, a slightly asymmetrical incident flow of the passage limiting elements 6, 6 occurs. For example, this can be realized by means of radius of different sizes at the corresponding edges of the top side 34a of the passages 34, 34 as well as opposite on the corresponding edges of the second end 62, 62 of the passage limiting elements 6, 6, not shown in FIG. 6. Alternatively, also other geometric designs can be used in order to achieve the asymmetrical incident flow. Furthermore, in the starting position the passage limiting elements 6, 6 can be arranged slightly inclined with respect to the pull-out direction A under a small angle in the direction of the inner surface 20 of the reception 2.
[0150] FIG. 7 schematically shows a front view of the pull-out body 3 of FIGS. 5 and 6 with passages 34, 34, 34, 34, 34, 34 and passage limiting elements 6, 6, 6, 6, 6, 6 present therein; the passages 34 to 34 are provided continuously and provided in two rows of three pieces each. The passage limiting elements 6 to 6 present in the passages 34 to 34 each are provided centrally on the bottom side 34a of the passages 34 to 34 and have a defined distance to the lateral edges 34b, 34c, and the top side 34d of the passages 34 to 34.
[0151] Due to the opposing deflection of the passage limiting elements 6, 6 shown in FIG. 6 the forces created by the passage limiting elements 6, 6, acting on the pull-out body 3, can be balanced to the maximum possible extent. Accordingly, in FIG. 7 with respect to one passage limiting element 6 to 6 the fold-out direction of the adjacent passage limiting elements 6 to 6 in the same row and of the passage limiting elements 6 to 6 in the next row directly above or below opposes to the fold-out direction of the one passage limiting element 6 to 6.
[0152] FIG. 8 shows an embodiment of the orthopedic device 1 similar to the one of FIG. 5 in a starting position. The passage limiting elements 6, 6 have a protrusion 68, 68 disposed at a first end 61, 61 on the first surface, which extends perpendicular to the pull-out direction A and protrudes into the passage cross-section without significantly influencing it. In the present embodiment the joint 66, 66 is a film joint according to FIG. 1 which is configured such that when the pull-out body 3 is pulled out with a physiological pull-out speed due to the caused leverage no or only a very little deflection of the passage limiting element 6, 6 occurs and the passage cross-section is not or only insignificantly changed in this area. Furthermore, due to the protrusion 68, 68 only negligibly low turbulences and whirlings W are created in the shear thickening fluid at these speeds.
[0153] The orthopedic device 1 of FIG. 8 is shown in FIG. 9 in a position different from the starting position. The passage limiting elements 6, 6 are deflected towards the inner surface 20 of the reception 2. The orthopedic device 1 has this position in terms of an unphysiological body movement, for example. The deflection of the passage limiting elements 6, 6 occurs due to the leverage of the flow dynamical forces onto the respective protrusion 68, 68. The effect of the deflection of the passage limiting elements 6, 6 on the viscosity of the shear thickening fluid corresponds to the one of the FIGS. 2 and 6. The protrusions 68, 68 can also serve for limiting the deflection movement of the passage limiting elements 6, 6.
[0154] FIG. 10 shows an orthopedic device 1 in a starting position, wherein the pull-out body 3 has an anchor-shaped passage limiting element 6, 6 each on its front side 30 and on its back side 31. The first ends 61, 61 of the passage limiting elements 6, 6 are connected to the pull-out body 3 in a torque-proof manner. In the starting position or the resting position the passage limiting elements 6, 6 point in pull-out direction A and differ therefrom solely around a small angle in the direction of the inner surface 20 of the reception. Thus, the form corresponds to an anchor with tight flukes. Thereby, the second end 62, 62 of each passage limiting element 6, 6 is very close to the pull-out body 3, so that a relatively large passage cross-section is provided. Accordingly, in the areas of the passage limiting elements 6, 6 the passage cross-section is only insignificantly smaller than the ones between the inner surface 20 of the reception 2 and the smooth front side 30 and back side 31 of the pull-out body.
[0155] At physiological body movements the forces caused by the flow only achieve insignificant or no changes with respect to the geometry of the flake-shaped passage limiting element 6, 6. Accordingly, the geometry of the passage limiting elements 6, 6 at physiological movements corresponds to the one in the starting position. By means of the configuration of the passage limiting elements 6, 6 at an acute angle to the pull-out direction A due to the form resulting when the pull-out body 3 is reset from a pulled-out position into the starting position a low flow resistance without or with only little generation of turbulences or whirlings W occurs. Alternatively, any desired number of passage limiting elements 6, 6 can be attached to the pull-out body 3.
[0156] FIG. 11 shows the orthopedic device 1 of FIG. 10 in a position different from the starting position. The passage limiting elements 6, 6 are bent according to their bending stiffness due to the flow dynamical forces acting on the first surface 63, 63 in the direction of the inner surface 20 of the reception 2. Thereby, the second end 62, 62 of each passage limiting element 6, 6 is closer to the inner surface 20 of the reception 2 reducing the passage cross-section compared to the starting position. This position of the orthopedic device 1 is typically caused by unphysiological body movements.
[0157] FIGS. 12a and 12b show an embodiment of the orthopedic device 1 with passage limiting elements 6, 6 in the form of torsion bodies which can be twisted around the longitudinal axis of the passage limiting elements 6, 6. The passage limiting elements 6, 6 are disposed on the lateral surfaces 32, 32 of the pull-out body 3 and are in a starting position. The passage limiting elements have a narrow side and a broad side. In the starting position the narrow side points in the pull-out direction. Thereby, between the passage limiting elements 6, 6 and the inner surface 20 of the reception 2 a maximum distance is provided.
[0158] In the present case, the twist of the passage limiting elements 6, 6 arises by means of a torsional moment which when pulling out the pull-out body 3 is caused by an asymmetrical geometry of the passage limiting elements 6, 6 with respect to the pull-out direction A and an asymmetrical incident flow resulting there from. Already in the starting position, the passage limiting elements 6, 6 have a slight twist along their longitudinal axis and are bent around an axis of curvature which is perpendicular to the longitudinal axis. Also other options for the generation of the torsional moment onto the passage limiting elements 6, 6 can be used such as one-sided attached protrusions in the area of the second ends 62, 62 of the passage limiting elements 6, 6.
[0159] FIGS. 13a and 13b show an orthopedic device 1 similar to the one of FIGS. 12a and 12b in a position differing from the starting position. Compared to the starting position in this position the passage limiting elements 6, 6 are twisted around a torsional angle so that a majority of the broad side of the passage limiting elements 6, 6 points in pull-out direction. Thereby, the projected surfaces in pull-out direction A of the passage limiting elements 6, 6 are increased leading to an increased pull-out resistance and an increased generation of turbulences and whirlings W. The projected areas are generated when the passage limiting elements 6, 6 are projected parallel to the pull-out direction A onto an area perpendicular to the pull-out direction A. The distance between the inner surface 20 of the reception and the passage limiting elements 6, 6 is reduced which creates a smaller cross-section. With an increasing torsional angle of the passage limiting elements 6, 6 the pull-out resistance rises and due to the decreased passage cross-section also the viscosity of the shear thickening fluid rises.
[0160] In FIG. 14 two passage limiting elements of an embodiment shown in a starting position of an orthopedic device 1 are configured on the pull-out body 3 in the form of pouches 7, 7. The pouches 7, 7 comprise passages 34, 34 on the pull-out body 3 which have a shell-shaped wall 74, 74 and a pouch opening 72, 72 on one side. Upon movement of the pull-out body 3 shear thickening fluid flows through the pouches 7, 7. Thus, the pouches 7,7 provide further discrete passage cross-sections. When the pull-out body 3 is pulled out of the reception 2 a first flow path of the shear thickening fluid is created through the passage cross-section between the inner surface 20 of the reception 2 and the pouches 7, 7, and further flow paths through the pouch openings 72, 72. The two pouches 7, 7 are disposed offset from one-another. Alternatively any number of pouches 7, 7 can be provided on the pull-out body.
[0161] FIG. 15 shows the orthopedic device 1 of FIG. 14 in a position differing from the starting position, wherein the device 1 is positioned at an unphysiological body movement. The pouch openings 72, 72 are blocked due to the high viscosity of the shear thickening fluid, i.e. the shear thickening, in the area of the pouch openings 72, 72, caused by the high pull-out speeds and the high shear rates resulting there from. The entire flow of the shear thickening fluid is led through the passage cross-section between the inner surface 20 of the reception 2 and the pouch 7, 7. This results in a strong increase of the shear rate. Additionally, the blocking of the pouch opening 72, 72 causes an increase of turbulences and whirlings W which also contribute to an increase of viscosity of the shear thickening fluid.
[0162] FIG. 16 shows the orthopedic device 1 of FIG. 14 in a starting position, wherein the reception 2 has a membrane 22 which divides the inside of the reception 2 into a first chamber 26 for housing the pull-out body 3 and a second chamber 27. Alternatively, any embodiment of the passage limiting elements 6 of the pull-out body 3 can be combined with the reception 2 having the membrane 22. The membrane 22 has an inlet opening 28 in the area of a second end of the reception 2 for incorporating the shear thickening fluid into the second chamber 27, and in the area of a first end of the reception 2 an outlet opening 29 for letting out the shear thickening fluid from the second chamber 27. Upstream of the inlet port 28 there is a stripper 24 for leading the shear thickening fluid from the first chamber 26 through the inlet opening 28 into the second chamber 27. In this embodiment the inlet port 28 is bigger than the outlet port 29. Alternatively, the proportions can be different depending on the configuration of the orthopedic device 1.
[0163] The second chamber 27 runs parallel to the pull-out body 3. Due to the elastic properties of the membrane 22 the latter extends perpendicular to the pull-out direction A towards the pull-out body 3 when the shear thickening fluid flows from the first chamber 26 into the second chamber 27. With the increase of the distance the pull-out body 3 travels in pull-out direction A, the membrane 22 is increasingly pushed in the direction of the pull-out body due to the increase of the shear thickening fluid led into the second chamber 27. This reduces the passage cross-section additionally and provides an even stronger back holding force.
[0164] FIG. 17 shows the orthopedic device of FIG. 16 in a position in which the membrane 22 is extended into the direction of the pull-out body 3. In this position the passage cross-section between the passage limiting element 6 and the membrane 22 in the first chamber 26 is additionally reduced by means of the expansion of the membrane 22 perpendicular to the pull-out direction A towards the pull-out body 3.
[0165] FIG. 18 shows an orthopedic device 1 with a reception 2 having an flexible rubber balancing membrane 4 which is attached to the bottom side of the reception 2. The orthopedic device 1 is in a starting position in which the pull-out body 3 is retracted with respect to the range of motion of the orthopedic device 1. The balancing membrane 4 is of an outwardly curved form with respect to the inside of the reception 2. The entire volume inside the reception 2 is filled with shear thickening fluid up to the sealing 12.
[0166] FIG. 19 shows the orthopedic device 1 of FIG. 18 in a position different from the starting position. Compared to the starting position the pull-out body 3 has been pulled out in pull-out direction A about a certain amount, thus, reducing the volume inside the reception 2 accordingly. The balancing membrane 4 balances the created negative pressure by means of bulging into the pull-out direction A according to the replaced volume inside the reception 2. In the present case the balancing membrane 4 has a form curved to the inside with respect to the inside of the reception 2. The balancing membrane 4 can be of any shape that is defined due to the position of the pull-out body 3 relative to the reception 2.
[0167] When the pull-out body 3 is pulled out due to the balancing of the volume within the reception 2 a vacuum effect can be prevented which would be disadvantageously for the viscosity of the shear thickening fluid and would provide an additional back holding force to the pull-out body 3. Thus, the balancing membrane 4 provides a pressure compensation within the reception 2, thereby, in particular in the area of physiological movements, a further increased ease of operation of the orthopedic device 1 can be provided compared to a rigid reception 2. Alternatively, the balancing membrane 4 can also be of a different flexible material, such as latex or a thermoplastic polyurethane.
[0168] FIG. 20a schematically shows a cross-sectional front view of an orthopedic device 1 with a passage limiting element 6 in the form of a shield in a starting position, such that the pull-out body 3 is surrounded by the passage limiting element 6 like an umbrella. In the starting position the umbrella-like passage limiting element 6 and the pull-out body 3 form a closed shield. The first end 61 of the passage limiting element 6, which surrounds the pull-out body, forms a torque-proof connection with the pull-out body 3. The umbrella-shaped passage limiting element 6 is made of natural rubber.
[0169] In terms of physiological pull-out speeds the umbrella-shaped passage limiting element 6 does not undergo any or undergoes only little deflection so that the fluid flow F relative to the pull-out body is only influenced slightly by means of the umbrella-shaped passage limiting element 6.
[0170] FIG. 20b schematically shows a cross-sectional top view of the orthopedic device 1 of FIG. 20a. Due to the close fitting of the umbrella-shaped passage limiting element 6 on the pull-out body 3 a larger passage cross-section is provided.
[0171] FIG. 21a schematically shows a cross-sectional top view of the orthopedic device according to FIG. 20a in a position differing from the starting position. Compared to the starting position the umbrella-shaped passage limiting element 6 is stretched towards the direction of the reception 2 reducing the passage cross-section between the reception 2 and the umbrella-shaped passage limiting element 6.
[0172] FIG. 21b schematically shows a cross-sectional top view of the orthopedic device according to FIG. 21a. Compared to the starting position a reduced passage cross-section is provided by means of the stretched umbrella-shaped passage limiting element 6. The umbrella-shaped passage limiting element 6 is in the stretched position in terms of unphysiological pull-out speeds and provides an increase of the viscosity of the shear thickening fluid between the umbrella-shaped passage limiting element 6 and the reception 2 and an increase of turbulences and whirlings W in the shear thickening fluid.
[0173] FIG. 22 schematically shows the development of viscosity of a shear thickening fluid, not described any closer herein, with respect to the shear rate for different passage cross-sections, wherein the viscosity is given logarithmically in Pas on the ordinate axis and the shear rate is given in s.sup.1 on the abscissa axis. The passage cross-sections only differ in the distances between the pull-out body and the inner surface of the reception, which are listed in the caption on the right side of FIG. 22. All four graphs show the typical behavior of shear thickening fluids. After an initial shear thinning due to an increasing homogenization of the fluid according to the increased particle movement, at a critical shear rate a rapid increase of the viscosity occurs, namely the jump in dilatancy. In other words, from the jump in dilatancy on there is a sudden shear thickening in the shear thickening fluid.
[0174] From FIG. 22 it is evident that with a decreasing passage cross-section on the one hand the viscosity increases at a constant shear rate and on the other hand the jump indilitancy already occurs at a lower shear rate. Thus, by means of a specific constructive adjustment of the passage cross-section of an orthopedic device 1 both the occurring viscosity as well as the position of the jump indilitancy can be adapted to the particular application.
[0175] FIG. 23 shows an ankle-joint orthosis 8 which has an orthopedic device 1. The orthosis is disposed around an ankle-joint, not shown, at two body portions, not shown, in a way that the ankle-joint is located between a first orthosis section 14 and a second orthosis section 16. The first orthosis section 14 and the second orthosis section 16 are connected by means of the orthopedic device 1, wherein the reception 2 is attached to the first orthosis section 14 and the pull-out body 3 is attached to the second orthosis section 16. In terms of a supination movement of the ankle-joint the pull-out body 3 is pulled out of the reception 2 in the scale of the radian measure resulting from the angle of the supination and the distance between the pull-out body 3 and the joint center. In the area of physiological movements the pull-out body 3 is not or only slightly restrained. If the supination speed is in the unphysiological area, a movement restriction of the two orthosis sections 14, 16 and, thus, of the two body portions towards each other occurs due to the strong back holding force of the orthopedic device 1 resulting therefrom.
[0176] FIG. 24 shows a wrist orthosis 9. The wrist orthosis 9 has a distal first orthosis section 14 and a proximal second orthosis section 16 of a wrist, not shown. The first orthosis section 14 and the second orthosis section 16 are connected by means of the orthopedic device 1 in a way that the pull-out body 3 is attached to the second orthosis section 16 and the reception 2 is attached to the first orthosis section 14. Dorsal extension of the wrist the pull-out body 3 is pulled out of the reception 2 according to the radian measure depending on the dorsal extension angle and the distance between the wrist rotation axis and the device. In terms of physiological movements the pull-out body 3 is not or only slightly restrained. If the dorsal extension speed is in the unphysiological area a restriction of movement of the two orthosis sections 14, 16 and, thus, of the two body portions towards each other occurs due to the resulting strong back holding forces of the orthopedic device 1.
LIST OF REFERENCE NUMERALS
[0177] 1 orthopedic device [0178] 2 reception [0179] 20 inner surface [0180] 22 membrane [0181] 24 stripper [0182] 26 first chamber [0183] 27 second chamber [0184] 28 inlet opening [0185] 29 outlet opening [0186] 3 pull-out body [0187] 30 front side [0188] 31 back side [0189] 32, 32 lateral surface [0190] 34, 34, 34, 34, 34, 34 passage [0191] 34a bottom side [0192] 34b, 34c lateral edge [0193] 34d top side [0194] 36 recess [0195] 37 inner side [0196] 4 balancing membrane [0197] 5 reset means [0198] 6, 6, 6, 6, 6, 6 passage limiting element [0199] 61, 61 first end [0200] 62, 62 second end [0201] 63, 63 first surface [0202] 64, 64 second surface [0203] 66, 66 joint [0204] 68, 68 protrusion [0205] 7, 7 pouch [0206] 71, 71 pouch opening [0207] 74, 74 shell-shaped wall [0208] 8 ankle-joint orthosis [0209] 9 wrist orthosis [0210] 12 sealing [0211] 14 first orthosis section [0212] 16 second orthosis section [0213] A pull-out direction [0214] F fluid flow relative to the pull-out body [0215] W turbulences and whirlings
