Removable device for attaching two mechanical parts

Abstract

A removable device for attaching two mechanical parts includes a pin removably locking a first part with respect to a second part, a retainer member on the pin and a resiliently loaded tension member which collaborate to prevent the pin from coming out of its locked position; the removable device further includes at least two inclined surfaces, the general shape of which is that of a projection oriented in the axial direction of the pin, such that when the pin rotates, the retainer member runs along the inclined surfaces and the pin moves between the locked position and unlocked position against a force exerted on the pin along a longitudinal axial direction of the pin exerted by the tension member.

Claims

1. An assembly comprising: a female part having a cavity with a cavity opening; a male part having a complementary nose configured to be inserted through the cavity opening and received in the cavity; a pin for securing the female part with the male part, the pin comprising a shaft having a longitudinal axis and a retainer member extending therefrom; the male and female parts each having a respective pin opening passing through a wall thereof, wherein the pin openings overlap when the nose is inserted in the cavity to axially receive the pin, which is configured to turn in a first direction in the pin openings to lock the nose to the cavity; and a tension member disposed between the male and female parts adjacent the pin openings, the tension member configured to engage and to be resiliently loaded by the retainer member when the pin is turned in the first direction, thereby preventing the pin from turning in a second direction opposite the first direction; the tension member comprising a ramp on a front surface thereof such that when the retainer member rotates in the first direction, said retainer member runs along said ramp moving between at least two positions against a force exerted on the pin in a longitudinal axial direction of the pin by said tension member, and a back surface opposite the ramp which engages an opposing surface of the male part; wherein in a locked configuration, a surface of the retaining member engages an opposing surface of the female part so that the retaining member is resiliently clamped between the tension member and the female part; wherein the ramp has a first configuration comprising a lower inclined surface followed by a planar portion followed by an upper inclined surface, or a second configuration comprising a lower flat surface followed by an inclined surface which is stepped-up from the flat surface in the longitudinal axial direction of the pin; and wherein each of the inclined surfaces are inclined relative to a plane perpendicular to the longitudinal axial direction of the pin and inclined relative to a plane parallel to the longitudinal axial direction of the pin.

2. The assembly according to claim 1, wherein the inclined surfaces are formed on one face of the tension member.

3. The Assembly according to claim 1, wherein the ramp comprises the first configuration and the lower inclined surface and the upper inclined surface form at least two inclined ramps, one after the other and separated by the planar portion, one of the ramps having a steeper slope than the other one.

4. The device according to claim 1, wherein the pin has the shape of a surface of revolution.

5. The device according to claim 4, wherein the pin is frustoconical.

6. The device according to claim 1, wherein the pin has a circular section.

7. The device according to claim 1, wherein the pin has an elliptical section.

8. The device according to claim 1, wherein the retainer member constitutes a transverse projection of the pin.

9. The device according to claim 8, wherein the retainer member is joined to the pin.

10. The device according to claim 1, wherein one of the ends of the pin has a coupling for a tool by means of which it is possible to apply a rotational movement to said pin about its longitudinal axis.

11. The device according to claim 1, wherein the tension member is a curved segment.

12. The assembly according to claim 1, wherein the ramp comprises the second configuration and the inclined surface is followed by an upper flat surface, such that the lower flat surface, the inclined surface, and the upper flat surface are directly subsequent to each other along the ramp.

13. The assembly according to claim 1, wherein the ramp comprises the first configuration, such that, when the retainer member is guided from the lower inclined surface along the ramp in the axially direction, the retainer member moves to a higher level along the ramp.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In order to better understand that which has been set forth, several drawings are enclosed in which several practical embodiments have been represented schematically and only by way of non-limiting example.

(2) In the drawings:

(3) FIG. 1 shows a perspective view of a tooth-tooth bar assembly of a bucket of an excavating machine with a device according to an embodiment of the invention;

(4) FIG. 2 shows a perspective view of the tooth of FIG. 1;

(5) FIG. 3 shows two side views of the tooth of FIG. 1;

(6) FIG. 4 shows two sectional views of the tooth of FIG. 2 according to A-A;

(7) FIG. 5 shows a sectional view of the tooth of FIG. 3, according to B-B;

(8) FIG. 6 shows a side view of the tooth bar of FIG. 1;

(9) FIG. 7 shows a sectional view of the tooth bar of FIG. 6 according to C-C;

(10) FIG. 8 shows a plan profile and sectional view of a cylindrical pin;

(11) FIG. 9 shows a plan profile and sectional view of a frustoconical pin;

(12) FIG. 10 shows three views of a tension member according to an embodiment of the invention and applicable in the assembly of FIG. 1;

(13) FIGS. 11A-C show three successive views showing the operation of a device according to an embodiment of the invention;

(14) FIG. 12 shows a perspective view of a tooth-tooth bar assembly of a bucket of an excavating machine with a device according to an embodiment of the invention;

(15) FIG. 13 shows a side view of the tooth bar of FIG. 12;

(16) FIG. 14 shows a sectional view of the tooth bar of FIG. 13 according to D-D:

(17) FIG. 15 shows a sectional view of the tooth and of the tooth of FIG. 12;

(18) FIG. 16 shows a tension member applicable in the assembly of FIG. 12;

(19) FIG. 17 shows a tension member applicable in the assembly of FIG. 12;

(20) FIG. 18 shows a tension member applicable in the assembly of FIG. 12;

(21) FIG. 19 shows a perspective view of a tooth-tooth bar assembly of a bucket of an excavating machine with a device according to an embodiment of the invention;

(22) FIG. 20 shows a side view of the tooth of FIG. 19;

(23) FIG. 21 shows a sectional view of the tooth of FIG. 20;

(24) FIG. 22 shows a side view of the tooth bar of FIG. 19;

(25) FIG. 23 shows a sectional view of the tooth bar of FIG. 22 according to E-E;

(26) FIG. 24 shows three views of a tension member applicable to the assembly of FIG. 19;

(27) FIGS. 25A-C show three successive views showing the operation of a device according to the embodiment of the invention shown in FIG. 19;

(28) FIG. 26 shows a perspective view of a tooth-tooth bar assembly of a bucket of an excavating machine with a device according to an embodiment of the invention;

(29) FIG. 27 shows a perspective view of a mounted tooth-tooth bar assembly of a bucket of an excavating machine with a device according to FIG. 26;

(30) FIG. 28 shows a tension member applicable in the assembly of FIG. 26;

(31) FIGS. 29A-C show three successive views showing the operation of a device according to the assembly of FIG. 26;

(32) FIG. 30 shows two views of a tension member according to an embodiment of the invention;

(33) FIG. 31 shows a sectional view of a tooth according to an embodiment of the invention;

(34) FIG. 31a shows a detail of the tooth of FIG. 13;

(35) FIG. 31b shows an enlarged detail of the tooth of FIG. 13a;

(36) FIG. 32 shows two views of a tension member according to an alternative embodiment of the invention;

(37) FIGS. 33A-C show three successive views showing the operation of a device using the tension member of FIG. 32;

(38) FIG. 34 shows a perspective view of a tooth-tooth bar assembly of a bucket of an excavating machine with a device according to an embodiment of the invention;

(39) FIG. 35 shows a plan, elevational and sectional view of a pin;

(40) FIG. 36 shows a plan, elevational and sectional view of a pin;

(41) FIGS. 37A-C show three successive views showing the operation of a device according to an embodiment of the invention with the pin of FIG. 35;

(42) FIG. 38 shows a side view of a tooth bar according to an embodiment of the invention applicable with the pin of FIG. 35 or FIG. 36;

(43) FIGS. 39A-C show three successive views showing the operation of a device according to an embodiment of the invention with the pin of FIG. 36 and the tooth bar of FIG. 38.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

(44) Embodiments of the invention applied, by way of example, to the assembly and removal of a tooth in a tooth bar of a bucket of an excavating machine are described below, but it is clear that the device can be used for the removable attachment of another type of mechanical parts.

(45) In reference to FIGS. 1 to 11, a tooth-tooth bar assembly 1 comprises a tooth 10, a tooth bar 20, a pin 30 and a resilient tension member 40, the latter formed by a metal member 43 located on a resilient member 44.

(46) The pin 30 is provided with a body, the shape of which is that of a surface of revolution, and of a transverse projection 31 constituting a retainer member for the pin itself. One of the ends of the pin 30 contains a recess 32 with the shape suitable for coupling a tool by means of which a rotational movement can be applied to the pin about its longitudinal axis.

(47) The tooth 10 is provided with a hole 11 with a notch 12 for being able to introduce the pin 30 with the projection or retainer member 31. It can also include a hole 11a with a notch 12a on the surface or side wall opposite to the previous one, such that it allows the introduction of the pin through either of the two sides. The tooth bar 20 includes a hole 21 for the pin 30 and a cavity 22 for housing the tension member 40. It is likewise possible to also include a hole 21a and a cavity 22a on the surface of the tooth bar opposite to the previous one.

(48) With the pin mounted in the assembly, the tension member 40 should not be loaded or significantly resiliently loaded, said tension member 40 remaining between the cavity 22 and the retainer member 31. Said tension member 40 is a curved segment and has the function of hindering the backwards movement, possibly caused due to the vibrations occurring in the excavation process, of the retainer member 31 from its assembly position (position C in FIG. 11) to its introduction or extraction position (position A in FIG. 11).

(49) The tooth-tooth bar assembly 1 is mounted first by coupling the tooth 10 and the tooth bar 20 with the tension member 40 previously housed in the cavity 22 of the tooth bar 20, then by introducing the pin into the holes of the tooth and the housing of the tooth bar and, lastly, rotating the pin by means of a suitable tool until the assembly or lock position in which the retainer member 31 of the pin 30 remains trapped between the tooth and the tooth bar. Due to the shape of the hole 11 of the tooth 10, the pin 30 can only be introduced in the precise position in which the retainer member 31 passes through the notch 12.

(50) In this embodiment, shown in FIG. 11 in three positions A, B and C, the tension member 40 formed by the metal portion 43 and resilient portion 44 is planar and an inner surface of the tooth 10 is provided with two inclined surfaces 13a and 13b ending in a projection 14. On the same inner surface of the tooth, next to inclined surface 13b, there is a cavity 15 for housing the retainer member 31 of the pin 30 in its lock position (position C in FIG. 11).

(51) Inclined surface 13a presents a first slight ramp which does excessively obstruct the forward movement of the retainer member 31 from position A to said lock position C, and a steep second ramp 13b making the backwards movement of the retainer member from position C to said unlock position A more difficult. The tension member 40 is housed in the cavity 22 and cannot be displaced, but it can be compressed since it is resilient, and this compression allows the forward movement of the retainer member 31 along the inclined surfaces 13a and 13b, passing through the projection 14 (position B in FIG. 11). Furthermore, as previously mentioned, when the pin is in its final lock position, the tension member 40 does not maintain a significant resilient compression load.

(52) In order to remove the tooth 10, the pin 30 is simply rotated from its lock position to the introduction or unlock position with enough force so that the retainer member 31 compresses the tension member 40 even more and overcomes the steep ramp of surface 13b, then all that remains is to easily extract the pin from the tooth bar and from the tooth.

(53) In this embodiment, the movements of the pin 10 are translational and rotational and the body of the pin will preferably be cylindrical (see FIG. 8). The pin has two translational movements until its assembly position, therefore conferring greater security to the retainer device given that its extraction requires a translational movement in one direction and subsequently a translational movement in the direction opposite to the previous one, thus making the accidental removal of the pin, and therefore of the tooth while working, difficult. The pin in this embodiment is preferably cylindrical given that the spaces for the possible housing of dirt between the pin and the housing thereof in the tooth bar are limited to the outer surface of the pin. If the pin used in this embodiment were frustoconical, there could be problems in the extraction thereof since the dirt which is introduced while the device is working could prevent the translational movement of the pin as it fills up those spaces existing between the pin and the housing in the tooth bar, creating dirt wedges around the outer surface of the pin.

(54) In another embodiment of the invention as shown in FIGS. 12 to 18, rather than being a curved segment, the tension member can be a circular washer 70 made up of a resilient portion 74 and a metal portion 73. When the tooth and tooth bar are applied to hot-working operations, said tension member 70 with a metal portion and another resilient portion may be replaced by a metal washer, such as a spring 76 or spring 75 for example.

(55) In this embodiment, the movements of the pin 30 are also axially rotational such that the body of the pin will preferably be cylindrical, since if it were frustoconical said translational movement would only be possible at the expense of a poor fitting of the pin 30 in the tooth 10 and the tooth bar 20.

(56) In another embodiment represented in FIGS. 19 to 25, the tension member 80 is provided with a planar entry surface 87 and two inclined surfaces 85a and 85b, which end in a projection 81, said inclined surfaces separating the initial introduction or unlocking position (corresponding to planar surface 87) of the retainer member 61 together with the pin 60 (position A in FIG. 25) from its final assembly or lock position, planar surface 86 of the tension member 80 (position C in FIG. 25). The assembly and removal process of this embodiment is similar to that of the previously explained embodiment, and in this embodiment, the lock position of the pin 60 is secure by virtue of the interaction between the resilient tension member 80, retainer member 61, planar surface 86 and surface 22. In said FIG. 25, it can be observed how the tension member 80 is compressed with respect to reference line R-R when the pin axially rotates and said tension member is compressed due to the action of the retainer member 61, without there being axial displacement of the pin 60. In these cases in which there is only a rotational and not axial movement of the pin, it is preferable for the pin to be frustoconical since during the unlocking operation, its being frustoconical facilitates its extraction, since the contact between the surface of the pin and of the housing is less and therefore should the gap between the pin and walls of the housing be full of dirt, the effort required to axially displace the pin will be less. Likewise, should the pin become deformed during the working of the retainer device, if said pin were cylindrical, rotation thereof would be more complicated since there would be greater contact between the pin and the housing in the tooth bar due to the constant section of the pin, however since it is frustoconical, the rotation will not be hindered due to there being less contact with the housing in the tooth bar.

(57) In this embodiment, a frustoconical pin 60 has been used (FIG. 9), although as in all the explained embodiments, frustoconical and cylindrical pins may be used indistinctly, although evidently the use of one rather than the other will be more advantageous according to the embodiment.

(58) In another embodiment of the invention represented in FIGS. 26 to 29, the tension member 100, with a metal portion 103 and a resilient portion 104, preferably with a curved segment shape, is provided with two downwardly inclined surfaces 105a and 105b separated from one another by a planar section 101 in its metal portion 103. There is also a planar area 106 at the end of said tension member 100. The operation is identical to that already described for the previous embodiments, but it allows different assembly positions in order to increase the pressure on the retainer member 61 of the preferably frustoconical pin 60 of the tooth 10. By means of this configuration, it is possible to displace the pin inwardly as the tooth 10 or tooth bar 20 becomes worn due to the effect of the shocks and vibrations generated between the tooth 10 and tooth bar 20.

(59) Three positions A, B and C are represented in FIG. 29 in which the axial rotation and axial translation displacement of the pin 60 along the metal surface 103 of the tension member 100 is observed.

(60) Another embodiment of the invention, represented in FIGS. 30 and 31, shares the same technical principle as the one described in FIGS. 26 to 29, with two downwardly inclined surfaces 53a and 53b, separated from one another by a planar surface 54, and said surfaces located on the inner wall or surface of the tooth 10. In this embodiment, after the inclined surface 53 the inner wall or surface of the tooth 10 has another planar surface 55 where the run of the retainer member 61 of the pin 60 ends, said pin 60 preferably being frustoconical. The tension member 130 used for this embodiment, formed by a metal portion 133 on a resilient portion 134, preferably with a curved segment shape, has its upper surface planar, straight and inclined, corresponding to the metal portion, with respect to its lower surface which is planar and straight, corresponding to its resilient portion.

(61) Another embodiment is represented in FIGS. 32 and 33, having the same operating principle as all the embodiments and similar in its construction to the embodiment shown in FIGS. 26 to 29. In this variant the tension member 90 has, as in the others, a metallic member 93 placed on top of a resilient portion 94, the upper surface of the metal portion 93 of the tension member having a first planar surface 97 followed by an inclined surface 95a, after which there is arranged a second inclined surface 95b and ending in a second planar surface 96. The second inclined surface 95b is almost perpendicular to planar surfaces 97, 96. The operation of this embodiment is similar to the previous ones, providing the fixing system with a self-tightening system.

(62) This device facilitates the extraction of the pin from its housing given that when the disassembly tool is turned, the pin comes out due only to the effect of the tension member which pushes it outwards. The height difference between the first planar surface 97 of the tension member 90 and the second planar surface 96 of said tension member 90 is the run of the axial displacement of the pin, allowing the arrangement of part of the pin outside of its housing prior to the introduction of the pin in the housing. This device is preferably applicable in dredging systems.

(63) In another embodiment shown in FIGS. 34 to 39, the tension member 113, 123 could be mounted or constructed on the pin 110, 120, specifically on the retainer member 111, 121 and having facing inclined surfaces defining a rib 14, 125 either on the inner surface of the tooth 10 or on the outer surface of the tooth bar 20.

(64) Specifically, and in view of FIGS. 34, 35 and 37, the tension member 113 is located on the lower portion of the retainer member 111 of the pin 110, locating the facing inclined surfaces 13a, 13b defining a rib 14 on the inner surface of the tooth 10, a housing 15 remaining for the retainer member 111 in its assembly position. In this device, the pin 110 carries out an axial rotation and translation displacement.

(65) However in view of FIGS. 36, 38 and 39, if the tension member 123 is located in the upper portion of the retainer member 121 of the pin 120, the facing inclined surfaces 127a, 127b defining a rib 125 must be located on the outer surface of the tooth bar 20, preceded on both sides by planar surfaces 124, 126. In this case, the displacement of the pin is also axially rotational and translational.

(66) Both configurations can be alternated according to the working requirements, being able to change the movements carried out by the pin.

(67) On the other hand, the specific shape of the inclined surfaces may be any shape suitable for facilitating the rotation of the pin from the unlocking position to the lock position and at the same time preventing the retainer member from being released from the lock position during normal working of the excavator. It is also possible to arrange more than two inclined surfaces if the embodiment so requires, mainly in those embodiments allowing several tightening positions between the tooth and tooth bar as the tooth bar becomes deformed.

(68) The invention has been described making reference to several specific embodiments, but a person skilled in the art could combine the different embodiments according to the application requirements and introduce variations and replace some members with other technically equivalent members, which will also be comprised within the scope of protection defined by the attached claims.