LOCK ASSEMBLY FOR A WEAR ASSEMBLY
20210262206 · 2021-08-26
Assignee
Inventors
- Adam SCRIVEN (Ashtonfield, New South Wales, AU)
- Hayden BUCHANAN (Fletcher, New South Wales, AU)
- William ELPHINSTONE (Warners Bay, New South Wales, AU)
Cpc classification
International classification
Abstract
A locking assembly is disclosed for securing a wear member to a support structure. The locking assembly includes a locking pin having a pin capable of securing the wear member to the support structure. The pin is disclosed as including pin portions that are interconnected through a coupling to allow torque to be transferred from at least one pin portion to the other pin portion and allow axial movement of one of the pin portions relative to the other pin portion in the direction of the pin axis. Also disclosed is a locking assembly to retain a pin in a predetermined position.
Claims
1. A locking assembly for securing a wear member to a support structure, the locking assembly comprising: a locking pin having a pin axis and comprising a first pin portion and a second pin portion that are spaced along the pin axis, the pin portions being interconnected through a coupling to allow torque to be transferred from at least one of the first or second pin portions to the other of the first or second pin portions and allow axial movement of one of the pin portions relative to the other pin portion in the direction of the pin axis; wherein the coupling is in the form of complementary coupling elements that interfit and extend in the direction of the pin axis.
2. The locking assembly of claim 1, further comprising a housing having an internal passage which extends along a longitudinal axis between first and second ends; and the pin being locatable within the housing with at least one of the pin portions being rotatable about the longitudinal axis within the housing.
3. The locking assembly of claim 1, wherein the coupling elements of the first and second pin portions are angularly spaced apart about the pin axis, and wherein the coupling elements of the first pin portion are arranged to be angularly offset from the coupling portions of the second pin portion so as to interfit with one another to form the coupling.
4. (canceled)
5. The locking assembly of claim 2, further comprising a transforming mechanism that causes the relative axial movement of the pin portions on rotation of at least one of the pin portions.
6. The locking assembly of claim 5, wherein the coupling causes both the first pin portion and the second pin portion to rotate together.
7. The locking assembly of claim 5, wherein the transforming mechanism comprises at least one cam and follower mechanism.
8. The locking assembly of claim 7, wherein the at least one cam includes a cam surface which is formed about at least one of the pin portions and the at least one follower is mounted to the housing and the follower remains in contact with the cam surface as the at least one pin portion rotates to cause relative axial movement of the pin portions.
9. (canceled)
10. The locking assembly of claim 2, wherein the pin portions are axially movable between an extended position and a retracted position, wherein when in the extended position, an end region of at least one of the pin portions extends beyond at least one of the ends of the housing, and when in the retracted position, of the pin portions is disposed within housing.
11-14. (canceled)
15. The locking assembly of claim 10, further comprising at least one retainer to retain at least one of the pin portions in a predetermined axial position.
16. The locking assembly of claim 15, wherein the retainer including a keeper, and a latch member engageable with the keeper in a latched position to retain the at least one pin portion in the predetermined axial position.
17. The locking assembly of claim 16, wherein the latch member comprises a c-shaped member having opposing arms that are caused to resiliently deform on engagement with the keeper.
18. The locking assembly of claim 17, wherein the predetermined position is the extended position.
19-30. (canceled)
31. The locking assembly of claim 18, wherein the latch member is biased to the latched position and the keeper forms part of the at least one follower and wherein the latch member is mounted along a portion of the cam surface such that as the at least one pin portion rotates the at least one follower remains in contact with the cam surface and moves the latch member against its bias to allow the latch member to move past, or into contact with, the keeper so that the pin portion is able to move into its predetermined axial position, whereafter the latch member is able to return to the latched position, and when in the latched position, the keeper engages with the latch member to retain the at least one pin portion in the predetermined position.
32. (canceled)
33. An excavation wear assembly for attachment of a wear member to a support structure, the excavation wear assembly comprising: the support structure having a nose portion which is configured to receive a socket of the wear member; a locking space formed in the support structure arranged to receive a locking assembly; the locking assembly comprising: a locking pin having a pin axis and comprising a first pin portion and a second pin portion that are spaced along the pin axis, the pin portions being interconnected through a coupling to allow torque to be transferred from at least one of the first or second pin portions to the other of the first or second pin portions and allow relative axial movement of the pin portions in the direction of the pin axis; wherein the coupling is in the form of complementary elements that interfit and extend in the direction of the pin axis, wherein the axial movement of one of the pin portions relative to the other pin portion in the direction of the pin axis are configured to secure the wear member to the support structure.
34. The excavation wear assembly of claim 33, wherein the locking assembly further comprises a housing locatable in the locking space of the support structure, the housing having an internal passage which extends along a longitudinal axis between first and second ends; and the pin locatable within the housing, wherein at least one of the pin portions is rotatable within the housing.
35. The excavation wear assembly of claim 33, wherein the pin portions are axially movable between an extended position and a retracted position.
36. The excavation wear assembly of claim 33, further comprising the wear member, the wear member having at least one retaining surface, and when the wear member is mounted to the support structure, the retaining surface is arranged to be aligned with the locking space of the support structure such that when the pin is in the extended position, the wear member is secured to the support structure, and when the pin is in the retracted position, the wear member is releasable from the support structure.
37. The excavation wear assembly of claim 36, wherein when the wear member is mounted to the support structure and when the pin is in the extended position, an end region of at least one of the pin portions extends beyond at least one of the ends of the housing and into engagement with the at least one retaining surface of the wear member to secure the wear member to the support structure, and when the pin is in the retracted position, the at least one of the pin portions is disposed within housing and disengaged from the at least one retaining surface of the wear member to allow the wear member to be removed from the support structure.
38-40. (canceled)
41. The excavation wear assembly of claim 33, wherein the locking assembly further comprises a transforming mechanism that causes the relative axial movement of the pin portions on rotation of at least one of the pin portions wherein, in use, the coupling causes the first pin portion and the second pin portion to rotate together.
42-51. (canceled)
52. The locking assembly of claim 17, wherein the c-shaped member is disposed in the pin and the keeper is disposed in the housing.
53-63. (canceled)
Description
BRIEF DESCRIPTION OF THE FIGURES
[0065] Embodiments will now be described by way of example only, with reference to the accompanying drawings in which
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DETAILED DESCRIPTION OF THE DISCLOSURE
[0096] In the following detailed description, reference is made to accompanying drawings which form a part of the detailed description. The illustrative embodiments described in the detailed description, depicted in the drawings and defined in the claims, are not intended to be limiting. Other embodiments may be utilised and other changes may be made without departing from the spirit or scope of the subject matter presented. It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings can be arranged, substituted, combined, separated and designed in a wide variety of different configurations, all of which are contemplated in this disclosure.
[0097] The present disclosure relates generally to excavation wear assemblies for digging equipment. In the illustrated embodiment, an excavation wear assembly is shown comprising a wear member that is mounted to a nose portion of a support structure that is fixed to a bucket lip or other digging edge. The nose portion may be part of the support structure or may be integrally formed to the digging edge. However, it is to be understood that embodiments of the present disclosure could be applied to excavation wear assemblies in which the wear member is mounted to an intermediate member (which may also be referred to as a support structure) that in turn is mounted to a nose that forms part of the digging edge or to the nose of a further tooth member that is mounted to the digging edge. In the excavation wear assemblies of the present disclosure, a lock is used to lock the wear member to the nose of the support structure or the nose integrally formed with the digging edge. Similarly, in excavation wear assemblies comprising an intermediate member, locks are used to lock the point to the intermediate member and the intermediate member to the nose formed with the digging edge or of the tooth member attached to the digging edge.
[0098] Referring to
[0099] As shown in
[0100] The coupling 30 includes complementary coupling elements 32 that interfit and extend in the direction of the pin axis. The coupling elements 32 of the first pin portion are angularly offset from the coupling elements 32 of the second pin portion so they interfit with one another. In the illustrated embodiment, the coupling elements 32 are in the form of fingers or splines that are angularly spaced apart about the pin axis. Together, the coupling elements 32 form the coupling 30 which is cylindrical in shape. The first pin portion 26 includes two coupling elements 32 that are angularly spaced apart by approximately 180°. As a result, the two coupling elements 32 are opposing one another. It is to be appreciated that different configurations of coupling elements are contemplated which may include more than two coupling elements on each pin portion.
[0101] Each coupling element 32 extends between a first end 34 and a second end 36 and includes radially extending inclined side surfaces 38. The side surfaces 38 are in contact to bear against one another to transfer torque between one pin portion to the other pin portion. Depending on the direction of the torque applied to the one pin portion, the side surfaces 38 that bear against one another will vary. Torque is applied to an end 42 of one of the pin portions, which then rotate about the pin axis in either a clockwise or a counter-clockwise direction. This arrangement disperses the forces across the side surfaces to prevent jamming of the pin portions during rotation.
[0102] In the illustrated embodiment, a drive arrangement 40 in the form of a hexagonal recess 40 is provided in the end 42 of the first pin portion to enable an operator to cause rotation of the locking pin 24 as required. This is carried out by the operator inserting an appropriately shaped tool into the recess 40. The manner in which the locking pin 24 is inserted into the locking space 22, means that after it has been inserted, the hexagonal recess 40 remains exposed at the end of the locking space 16. This allows for easy access to the recess 40 for access to the drive arrangement 40 and for removal of the locking pin 24 from the locking space 22 when required.
[0103] The locking assembly further includes a housing 44. The housing 44 includes a body 45 that includes a hollow passage 46 that extends along a longitudinal axis between first 48 and second 50 ends. The locking pin 24 is locatable within the housing 44. The hollow passage 46 of the body 45 is cylindrical to allow rotation of the pin portions within the passage 46. The housing 44 is locatable in the locking space 22 which is formed in the support structure 14, and the locking pin 24 is locatable in the housing 44. The external shape of body 45 is non-circular so that the housing 44 does not rotate relative to the support structure 14. For example, in the illustrated embodiment, the body 45 is elongated at its upper surface which prevents rotation of the housing relative to the support structure 14. The housing 44 also includes a collar 52 positioned about the second end 50. The collar 52 extends laterally relative to the longitudinal axis and allows the housing 44 to only be inserted and removed from one side of the support structure 14. The locking space 22 of the support structure is enlarged at one end to include a recess 54 also formed in the support structure that extends about the one end of the locking space 22. A concavely curved surface forms the enlarged recess 54 in the support structure and the collar 52 includes a shoulder portion 56 that is convexly curved to be complementary and engage one another when the housing 44 is inserted into the support structure 14. The curved surfaces help reduce wear on the housing and the support structure 14. The collar 52 is also elongated to correspond to the shape of the external surface of the body 45. In alternative embodiments, the external surface of the housing may be any non-circular shape, such as oval, hexagonal, etc.
[0104] The pin portions 26, 28 are axially movable between a retracted (
[0105] As best shown in
[0106] A transforming mechanism causes the axial movement of one of the pin portions 26, 28 relative to the other pin portion 26, 28 between the extended and the retracted positions on rotation of at least one of the pin portions. In the illustrated embodiment, the first pin portion 26 is rotated and then both the first pin portion 26 and the second pin portion 28 rotate together. The transforming mechanism includes at least one cam and follower mechanism, but multiple cam and follower mechanisms may be provided. For example, in the illustrated embodiment, each pin portion 26, 28 includes a cam 62 and follower 64 mechanism. In alternative embodiments, the cam 62 and follower 64 mechanism may be replaced by corresponding threads, or a J-slot capable of inducing the longitudinal displacement of the pin portions.
[0107] Each cam 62 includes a cam surface 66 in the form of a helical portion that extends over the surface of the pin portion 26, 28 helically relative to the pin axis of the locking pin 24. The helical portion is in the form of a groove 66. Each pin portion 26, 28 extends from the external end 42 to an end 43 located internal the housing 44. The helical groove 66 extends about 360° from the external end 42 towards the internal end 43 of each pin portion 26, 28 and finishes in at least one retainer 69 for receiving the follower 64 when the locking pin 24 is in its extended position. The helical groove varies in pitch such that proximal each end of the groove, the groove extends radially having close to zero pitch, and between the ends of the groove, the pitch of the groove increases for a portion. The pitch of the groove 66 affects the axial displacement of the pin portions 26, 28. The groove 66 of each pin portion 26, 28 is identical such that, in position in the housing 44, the grooves 66 are mirror images of one another. In alternative embodiments, the cam surfaces may be longer or shorter distances about the respective pin portion than one another, may extend at a different pitch about the pin portion, and may also be different shapes. Different cam surfaces will affect the relative axial displacement of the pin portions. Also, the cam surfaces do not need to be identical.
[0108] The follower 64 is in the form of a projection 68 that projections that projects radially from the housing 44 into the passage 46. The follower 64 is designed to engage the cam surface as the pin portion rotates between the extended and retracted positions. The follower 68 is configured to be received in the groove 66 of the respective pin portion 26, 28.
[0109] According to
[0110] The biasing member 70 includes a rigid portion 72 and a resilient portion 74. The rigid portion is in the form of a hemispherical projection 72 that is shaped to locate in the recessed end of the keeper. It is also shaped to ride in the groove of the pin portions 26, 28. The rigid portion 72 extends into the path of the helical groove 66 so as to engage the follower and allow the follower 64 to travel past it during rotation of the pin portions 26, 28. The resilient portion 74 of the biasing member 70 compresses the biasing member 70 against its bias to follow the path of the groove 66.
[0111] In the illustrated embodiment, the resilient portion 74 comprises concentric layers of elastomeric material positioned below the rigid portion 72 in the hole. It is the resilient portion 74 which compresses upon engagement of the follower 64 with the rigid portion 72. The resilient portion 74 is able to be compressed by its expansion into a wall defining the hole. Alternatively, the resilient portion may be replaced by any resilient material such as a spring also compressible within the hole. In operation, the keeper 70 is biased so as to extend into the path 62 (either the cam surface or a part of the helical portion) of the follower 64 (i.e., the latch) during rotation of the pin portions 26, 28. As the pin portions 26, 28 rotate the follower travels in the path of the groove past the keeper to the latched position and to retain the pin portions in the predetermined position. The follower/latch 64 engages the keeper 70 to move the keeper 70 against its bias as it travels along the groove while engaging the cam surface. Once the follower 64 passes over the keeper it is in the latched position. In the latched position, the keeper 70 returns to its biased position. In its biased position, the keeper 70 engages with the latch 64 to retain the pin portions in the predetermined position. In the illustrated embodiment, the predetermined position is the extended position.
[0112] As a further alternative, the latch may include a biasing member rather than the keeper. As a further alternative, the latch may be in the form of a locking detent that includes a depressible boss. The detent has a resilient portion that is designed to engage in a dimple in the groove to retain the detent in a locking position.
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[0114] The wear member 14 includes ears that extend away from the digging edge on either side of the socket. Each ear includes an aperture 78that, in operation, is aligned with the locking space 22 of the support assembly. As a result, the tool is able to access the end 42 of the locking pin 24 to move the locking pin 24 from the retracted to the extended position and vice versa.
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[0116] Often there may be some wear on the relevant surfaces of the wear member 12, the support structure 14 or the locking assembly 15 after the parts have been used. When the pin 24 is fully in the extended position, the taper on the ends of the pin 24, the angle of the wall 90 of the aperture 78 of the wear member 14, the resilient nature of the at least one retainer, and the coupling 30 including interfitting coupling elements that are able to accommodate relative axial movement are able to pull the wear member 12 onto the support structure 14.
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[0118] In relation to the locking assembly 116, the primary difference is that a biasing member is included about the coupling 30. In the illustrated embodiment, the biasing member is in the form of a spring 180. The spring is shown in
[0119] In relation to the at least one retainer 169, a second embodiment is shown in
[0120] The nodule 186 is also able to retain the keeper 64 in the latched position and the latching pin 24 in the extended position.
[0121] The spring steel arrangement 170 is not limited to being positioned in the wall of the groove 66. Alternatively, the spring steel arrangement may be positioned in the path of the groove 66 along the cam surface so as to engage the keeper.
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[0123] As also discussed above, the coupling 230 includes complementary coupling elements 290, 292 that they interfit and extend in the direction of the pin axis. The coupling elements 290, 292 are fit together in an arrangement that is similar to a tongue and groove connection. Together, the coupling elements 290, 292 form the coupling 230 which is cylindrical in shape.
[0124] The first pin portion 26 includes two coupling elements 290 (which form a portion of the coupling 230) that are angularly spaced apart by approximately 180°. In between the coupling elements 232 is a groove or channel 294 which receives the coupling elements 292 of the second pin portion 28. The channel 294 extends from the second end 236 towards the first end 234, and bifurcates into two channels 295 in the direction of the direction of the pin axis having a portion of the coupling therebetween. Each bifurcated channel 295 is shallower than the channel 294 and is defined by side walls 297 and a floor 298 which are shaped to receive the coupling elements 292 of the second pin portion.
[0125] The second pin portion 28 includes two coupling elements 292 (which form part of the coupling 230) which in use, oppose and complement the groove 294 to fit together closely. Likewise, the coupling elements 292 are also angularly spaced apart by approximately 180°. In this embodiment, the coupling elements 292 are shaped (and resemble) a U-shape including two parallel sides 296. The sides 296 of the U-shape are received in the bifurcated channels 294 and are able to abut against the side walls 297 in the retracted position.
[0126] In particular, the bearing surfaces are the parallel sides 296 rather than the angled bearing surfaces in the first embodiment. This arrangement in the third embodiment as it allows for a closer fit of the coupling elements 290, 292 inside the channel 294. This helps to prevent jamming of the pin portions during rotation and during axial movement of the pin portions relative to one another.
[0127] Further, the third embodiment of the “tongue and groove” coupling 230 is also shown in
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[0130] The at least one retainer 369 includes the keeper 64 as shown in relation to the other embodiments, the coupling 230 as shown in relation to the third embodiment, and a third embodiment of the latch member 370. The latch member 370 is in the form of a spring material, preferably spring steel, arrangement that is biased to extend into the groove 66. The spring steel arrangement 370 is in the form of a C-shaped spring clip. The C-shaped spring clip is received in a similarly shaped depression 390 in the path defined by the groove 66. The C-shaped spring clip includes two arms 382 that are biased towards one another to a natural or rest position. There are gaps 388 between each arm 382 in their natural rest position and the wall of the depression towards the top. As the C-shaped spring clip rides past the keeper 64, the arms 382 move against their bias away from one another. When the keeper 64 engages the C-shaped spring clip 370, the spring steel arrangement is sprung such that the arms 382 respectively move into the gaps 388 (and towards each wall).
[0131] The arms 382 retain the keeper 64 in the latched position and the latching pin 24 in the extended position. In this way, the arms 382 of the spring clip 370 block the groove 66 until a threshold force is applied to force the keeper 64 to engage the arms 382 and move the arms 382 against their bias. Subsequently, once the threshold force is reached, the keeper 64 is able to ride past (or through) the C-clip to allow the latch assembly to move to the retracted position.
[0132] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.