Fixing Structure of Replacement Component in Work Machine and Lock Member for the Fixing Structure

Abstract

This fixing structure is provided with an attachment part, a pin member, and a lock member. The replacement component is attached to the attachment part. The attachment part includes a pin hole. The pin member is disposed in the pin hole. The lock member is engaged with the pin member and retains the pin member. The lock member includes an opening, a groove part, a holding part, and a resistance part. The groove part extends from the opening and engages with the pin member. The holding part is provided in the groove part and holds the pin member in a manner that prevents separation of the pin member. The resistance part is provided between the opening and the holding part in the groove part. The resistance part comes into contact with the pin member at the time of engagement with the pin member to give a feeling of resistance.

Description

Technical Field

[0001] The present invention relates to a fixing structure of a replacement component in a work machine, and a lock member for the fixing structure. Background Art

[0002] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field. [0002a] Conventionally, a fixing structure for attaching a replacement component in a work machine is known. For example, Patent Document 1 discloses the fixing structure for attaching a bucket tooth to a tooth adapter. The fixing structure includes a pin member and a lock member. The tooth and the tooth adapter are each provided with a pin hole, and the pin member is inserted into the pin holes of the tooth and the tooth adapter. The lock member engages with the pin member to prevent the pin member from coming off.

[0003] The lock member has a U-shaped groove portion that engages with the pin member. A holding portion for holding the pin member is provided on an inner surface of the groove portion. The holding portion includes a pair of protrusions disposed on opposite sides in the groove portion. When the lock member is engaged with the pin member, the pin member rides over the holding portion and deforms the lock member so as to press and expand the groove portion, thereby engaging with the groove portion. Accordingly, the operator can determine that the lock member is engaged with the pin member by feeling a response by the pin member passing over the holding portion. After the lock member is engaged with the pin member, the 2023437963   29 Jul 2026 lock member returns to its original shape. Thus, the lock member is held in a state of being engaged with the pin member by the holding portion. Patent Literature

[0004] Patent Document 1: JP 2021-042633 A Summary of Invention

[0005] In the above-described fixing structure, the holding portion may be worn due to use of the work machine. When the holding portion is worn, in a case where the lock member is engaged with the pin member again after the lock member is removed from the pin member, it is not possible to obtain the same response as that at the time of the initial engagement. Therefore, it is difficult for the operator to determine whether or not the lock member is engaged with the pin member. Therefore, the lock member detached from the pin member cannot be reused, and a new lock member is required every time the replacement component is replaced. At least some embodiments of the present invention provide the fixing structure for a replacement component in a work machine and a lock member, which enable reuse of the lock member and easy determination of engagement of the lock member. [0005a] In one aspect, the invention provides a fixing structure for detachably fixing a replacement component in a work machine, the fixing structure comprising: an attachment portion including a pin hole and to which the replacement component is attached; a pin member disposed in the pin hole; and a lock member that engages with the pin member and prevents the pin member from coming off; wherein the lock member includes: an opening; a groove portion that engages with the pin member, the groove portion extending from the opening; a holding portion that holds the pin member such that the pin member does not come off, the holding portion being provided in the groove portion; and a resistance portion that comes into contact with the pin member to give a tactile response when engaging with the pin member, the 2023437963   29 Jul 2026 resistance portion being provided between the opening and the holding portion in the groove portion; the groove portion further includes: a curved portion that engages with the pin member; an inner portion inclined and extending from the opening toward the curved portion; and a bulging portion disposed between the curved portion and the inner portion and bulging to an inner side of the curved portion; the holding portion includes a pair of first protrusions disposed between the bulging portion and the curved portion; and the resistance portion includes a pair of second protrusions disposed between the inner portion and the curved portion. [0005b] Another aspect of the invention provides a lock member that engages with a pin member that detachably fixes a replacement component in a work machine to prevent the pin member from coming off, the lock member comprising: an opening; a groove portion that engages with the pin member, the groove portion extending from the opening; a holding portion that holds the pin member such that the pin member does not come off, the holding portion being provided in the groove portion; and a resistance portion that comes into contact with the pin member to give a tactile response when engaging with the pin member, the resistance portion being provided between the opening and the holding portion in the groove portion; the groove portion further includes: a curved portion that engages with the pin member; an inner portion inclined and extending from the opening toward the curved portion; and a bulging portion disposed between the curved portion and the inner portion and bulging to an inner side of the curved portion; the holding portion includes a pair of first protrusions disposed between the bulging portion and the curved portion; and the resistance portion includes a pair of second protrusions disposed between the inner portion and the curved portion.

[0006] Fixing structure according to one aspect of the present invention is the fixing structure for detachably fixing a replacement component in a work machine. The fixing structure includes an attachment portion, a pin member, and a lock member. The replacement component is attached to the attachment portion. The attachment portion includes a pin hole. The pin member 2023437963   29 Jul 2026 is disposed in the pin hole. The lock member engages with the pin member and prevents the pin member from coming off. The lock member includes an opening, a groove portion, a holding portion, and a resistance portion. The groove portion extends from the opening and engages with the pin member. The holding portion is provided in the groove portion and holds the pin member such that the pin member does not come off. The resistance portion is provided between the opening and the holding portion in the groove portion. The resistance portion comes into contact with the pin member when engaging with the pin member, and gives a response.

[0007] A lock member according to another aspect of the present invention engages with a pin member that detachably fixes a replacement component in a work machine to prevent the pin member from coming off. The lock member includes an opening, a groove portion, a holding portion, and a resistance portion. The groove portion extends from the opening and engages with the pin member. The holding portion is provided in the groove portion and holds the pin member such that the pin member does not come off. The resistance portion is provided between the opening and the holding portion in the groove portion. The resistance portion comes into contact with the pin member when engaging with the pin member, and gives a response.

[0008] According to the present invention, the resistance portion for providing a resistance to an operator at the time of engagement is provided separately from the holding portion that holds the pin member such that the pin member does not come off. Accordingly, even if the holding portion is worn when the lock member is reused, it is possible for the operator to obtain a response substantially equal to that of a new lock member. This makes it possible to easily determine the engagement of the lock member. [0008a] Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like are to be construed in an inclusive sense as 2023437963   29 Jul 2026 opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”. Brief Description of Drawings

[0009] FIG. 1 is a perspective view illustrating the fixing structure according to an embodiment.

[0010] FIG. 2 is an exploded perspective view of the fixing structure.

[0011] FIG. 3 is a perspective view of a tooth as viewed from a base end side.

[0012] FIG. 4 is a view illustrating a lock member.

[0013] FIG. 5 is a cross-sectional view of the fixing structure taken along line V-V in FIG. 1.

[0014] FIG. 6A is a view illustrating the operation of fixing the tooth to a tooth adapter.

[0015] FIG. 6B is a view illustrating the operation of fixing the tooth to the tooth adapter.

[0016] FIG. 7 is an enlarged view of the lock member.

[0017] FIG. 8 is an enlarged view of an engaging portion.

[0018] FIG. 9 is a view of the lock member according to a first modified example.

[0019] FIG. 10 is a view of the lock member according to a second modified example.

[0020] FIG. 11 is a view of the lock member according to a third modified example. 2023437963   29 Jul 2026 Description of Embodiments

[0021] Hereinafter, fixing structure of a replacement component in a work machine according to an embodiment will be described with reference to the drawings. FIG. 1 is a perspective view illustrating a fixing structure 1 according to an embodiment. FIG. 2 is an exploded perspective view of the fixing structure 1. As illustrated in FIGS. 1 and 2, the fixing structure 1 includes a tooth adapter 3, a tooth 4, a pin member 5, and a lock member 6. In the present embodiment, the fixing structure 1 is a structure for fixing the tooth 4 to a bucket 2 of a hydraulic excavator. That is, in the present embodiment, the tooth 4 corresponds to a replacement component.

[0022] The tooth adapter 3 is fixed to the bucket 2. The tooth 4 is attached to the tooth adapter 3. The tooth 4 is attached to the bucket 2 via the tooth adapter 3. The tooth 4 is worn by the use of the bucket 2. The tooth 4 that has been worn is removed from the bucket 2 and replaced with a new tooth 4.

[0023] As illustrated in FIG. 2, the tooth adapter 3 includes a fixing portion 11 and an attachment portion 12. The fixing portion 11 is fixed to the bucket 2. For example, the fixing portion 11 is fixed to the bucket 2 by welding. The fixing portion 11 includes a first fixing portion 13 and a second fixing portion 14. The first fixing portion 13 and the second fixing portion 14 are disposed apart from each other. The bucket 2 is disposed between the first fixing portion 13 and the second fixing portion 14.

[0024] The attachment portion 12 has a tapered shape. The first fixing portion 13 and the second fixing portion 14 protrude from the attachment portion 12 toward a proximal end side. The attachment portion 12 includes a first pin hole 15. The first pin hole 15 penetrates the attachment portion 12 in the left-right direction. The tooth 4 has a tapered shape. The tooth 4 includes a tip end portion 16 and a base end portion 17. The term " tip end side " means a 2023437963   29 Jul 2026 direction from the base end portion 17 toward the tip end portion 16 of the tooth 4. The term " base end side " means a direction from the tip end portion 16 toward the base end portion 17 of the tooth 4. The term " left-right direction " means a direction orthogonal to a direction from the base end portion 17 toward the tip end portion 16 of the tooth 4, and corresponds to the left-right direction of the bucket 2.

[0025] FIG. 3 is a perspective view of the tooth 4 as viewed from the base end side. As illustrated in FIG. 3, the base end portion 17 of the tooth 4 includes a recess portion 18. The recess portion 18 has a shape recessed toward the tip end side. The attachment portion 12 of the tooth adapter 3 is disposed in the recess portion 18. The recess portion 18 includes a first inner side surface 21 and a second inner side surface 22. The first inner side surface 21 is provided with a first guide groove 23. The first guide groove 23 extends from the base end portion 17 toward the tip end side of the tooth 4. The second inner side surface 22 is provided with a second guide groove 24. The second guide groove 24 extends from the base end portion 17 toward the tip end side of the tooth 4. The tooth 4 includes second pin holes 25, 26. The second pin holes 25, 26 penetrate the tooth 4. The second pin hole 25 is provided in the first guide groove 23. The second pin hole 26 is provided in the second guide groove 24.

[0026] The pin member 5 is disposed in the first pin hole 15 and the second pin holes 25, 26. The pin member 5 engages with the tooth 4 and the tooth adapter 3, thereby fixing the tooth 4 and the tooth adapter 3 to each other. The pin member 5 includes an annular pin groove 27. The pin groove 27 has a shape recessed from an outer circumferential surface 28 of the pin member 5.

[0027] The lock member 6 engages with the pin member 5, thereby preventing the pin member 5 positioned in the first pin hole 15 and the second pin holes 25, 26 from being released. The lock member 6 engages with the pin groove 27 of the pin member 5. The lock member 6 is formed of a steel material such as manganese steel. The lock member 6 has a bent 2023437963   29 Jul 2026 plate shape. FIG. 4 is a view illustrating the lock member 6. As illustrated in FIG. 4, the lock member 6 includes an engaging portion 31, a pressing portion 32, and a connecting portion 33. The engaging portion 31 engages with the pin member 5. The engaging portion 31 includes a U-shaped groove 34 and an opening 35. The pin groove 27 of the pin member 5 is disposed in the groove portion 34, so that the engaging portion 31 engages with the pin member 5. The groove portion 34 communicates with the opening 35.

[0028] The pressing portion 32 has a shape bent with respect to the connecting portion 33. The pressing portion 32 is a portion that is pressed by a jig when the lock member 6 is engaged with the pin member 5. The connecting portion 33 is disposed between the engaging portion 31 and the pressing portion 32. The connecting portion 33 connects the engaging portion 31 and the pressing portion 32. The lock member 6 has a narrowed shape at the connecting portion 33. The engaging portion 31 and the connecting portion 33 have a flush plate shape.

[0029] FIG. 5 is a cross-sectional view of the fixing structure 1 taken along line V-V in FIG. 1. As illustrated in FIG. 5, the lock member 6 is inserted into a gap between the attachment portion 12 of the tooth adapter 3 and the first inner side surface 21 of the tooth 4, and engages with the pin member 5 in the tooth 4. The pressing portion 32 is located behind the base end portion 17 of the tooth 4 and is exposed to the outside.

[0030] Next, the operation of fixing the tooth 4 to the tooth adapter 3 will be described. First, as illustrated in FIG. 6A, the tooth 4 is placed over the attachment portion 12 of the tooth adapter 3, whereby the attachment portion 12 of the tooth adapter 3 is disposed in the recess portion 18 of the tooth 4. Then, the pin member 5 is inserted into the first pin hole 15 of the tooth adapter 3 and the second pin holes 25, 26 of the tooth 4. Next, as illustrated in FIG. 6B, the lock member 6 is inserted into the first guide groove 23. Then, an operator presses the pressing portion 32 of the lock member 6 toward the tip end side using a jig. As a result, the 2023437963   29 Jul 2026 lock member 6 slides along the first guide groove 23, and the engaging portion 31 engages with the pin member 5 as illustrated in FIG. 5.

[0031] In the above description, the case where the lock member 6 is inserted into the first guide groove 23 has been described. However, the lock member 6 may be inserted into the second guide groove 24. That is, the lock member 6 may be inserted into a gap between the attachment portion 12 of the tooth adapter 3 and the second inner side surface 22 of the tooth 4.

[0032] Next, the structure of the lock member 6 will be described in detail. In the following description, a direction from the pressing portion 32 toward the engaging portion 31 is referred to as a front side, and the opposite direction is referred to as a rear side. In addition, a direction orthogonal to the front-rear direction in each drawing is referred to as the left-right direction. FIG. 7 is an enlarged view of the lock member 6. As illustrated in FIG. 7, the groove 34 is open to the front side. The groove portion 34 includes a curved portion 41, a first bulging portion 42, a second bulging portion 43, a first inner portion 44, and a second inner portion 45. The curved portion 41, the first bulging portion 42, and the second bulging portion 43 engage with the pin member 5.

[0033] The curved portion 41 has an arc shape. The curved portion 41 has an inner diameter larger than that of the pin groove 27. The first bulging portion 42 and the second bulging portion 43 are disposed apart from each other in the left-right direction. The first bulging portion 42 and the second bulging portion 43 bulge to the inner side of the curved portion 41. The first bulging portion 42 is located between the first inner portion 44 and the curved portion 41. The second bulging portion 43 is located between the second inner portion 45 and the curved portion 41.

[0034] In FIG. 7, the double-dashed line indicates the pin member 5 located at an engagement position. The pin member 5 engages with the groove portion 34 at the engagement position. In FIG. 7, a portion where the pin member 5 and the lock member 6 overlap each other 2023437963   29 Jul 2026 in the axial direction of the pin member 5 is hatched. As illustrated in FIG. 7, the first bulging portion 42 and the second bulging portion 43 increase the area of the portion where the pin member 5 and the lock member 6 overlap each other. This firmly prevents the pin member 5 from falling off in the axial direction.

[0035] As illustrated in FIG. 7, the first inner portion 44 and the second inner portion 45 are disposed apart from each other in the left-right direction. The first inner portion 44 is located on the right side of the groove portion 34, and the second inner portion 45 is located on the left side of the groove portion 34. The first inner portion 44 extends to the front side from the first bulging portion 42. The first inner portion 44 is inclined with respect to the front-rear direction toward the front side and the outer side in the left-right direction. The second inner portion 45 extends to the front side from the second bulging portion 43. The second inner portion 45 is inclined with respect to the front-rear direction toward the front side and the outer side in the left-right direction. The distance between the first inner portion 44 and the second inner portion 45 increases toward the front side.

[0036] The engaging portion 31 includes a holding portion 46 and a resistance portion 47. The holding portion 46 and the resistance portion 47 are provided on the inner surface of the groove portion 34. The holding portion 46 holds the pin member 5 so as not to fall off. The holding portion 46 includes a pair of first protrusions 48, 49 disposed on opposite sides in the left-right direction in the groove portion 34. The pair of first protrusions 48, 49 protrude toward the inner side of the groove portion 34. Specifically, the first protrusion 48 is provided on the first bulging portion 42. The first protrusion 49 is provided on the second bulging portion 43.

[0037] FIG. 8 is an enlarged view of the engaging portion 31. As illustrated in FIG. 8, the holding portion 46 holds the pin member 5 by contacting the pin member 5 in the pin groove 27 so that the pin member 5 does not fall off from the engagement position. In FIG. 8, the pin 2023437963   29 Jul 2026 member 5 indicated by the double-dashed line indicates the position of the pin groove 27 of the pin member 5.

[0038] The resistance portion 47 is disposed between the holding portion 46 and the opening 35. The resistance portion 47 comes into contact with the pin member 5 when engaging with the pin member 5, and gives a response. As illustrated in FIG. 7, the resistance portion 47 includes a pair of second protrusions 51, 52 disposed on opposite sides in the left-right direction in the groove portion 34. The pair of second protrusions 51, 52 protrude toward the inner side of the groove portion 34. The second protrusion 51 is provided on the first inner portion 44. The second protrusion 52 is provided on the second inner portion 45. The width between the pair of second protrusions 51, 52 is narrower than the width between the pair of first protrusions 48, 49. The width between the pair of second protrusions 51, 52 is narrower than the outer diameter of the pin groove 27.

[0039] In FIG. 8, the position of the pin member 5 before engagement is indicated by the single-dashed line 5 ‘. The resistance portion 47 is provided so as to generate a resistance force by contacting the pin member 5 before the pin member 5 reaches the engagement position when the lock member 6 is engaged therewith. That is, the pin member 5 enters the groove portion 34 from the opening 35. Then, when passing through the resistance portion 47, the pin member 5 pushes and expands the resistance portion 47. As a result, the lock member 6 is elastically deformed, and a resistance force is generated by a reaction force thereof. Thus, the resistance portion 47 gives a tactile response when the lock member 6 is engaged with the pin member 5. In addition, in a state where the pin member 5 is located at the engagement position, the resistance portion 47 does not contact the pin member 5.

[0040] According to the fixing structure 1 of the present embodiment described above, the resistance portion 47 for providing a resistance at the time of engagement is provided separately from the holding portion 46 that holds the pin member 5 so as not to come off. Accordingly, 2023437963   29 Jul 2026 even if the holding portion 46 is worn when the lock member 6 is reused, it is possible to obtain a response substantially equal to that of a new lock member 6. This makes it possible to easily determine the engagement of the lock member 6.

[0041] Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the invention.

[0042] The work machine is not limited to a hydraulic excavator and may be another machine such as a bulldozer, a wheel loader or a grader. The replacement component is not limited to the tooth 4, and may be another component such as a lip shroud, a side shroud, or a ripper point.

[0043] The structure of the lock member 6 is not limited to that of the embodiment described above and may be changed. For example, FIG. 9 is an enlarged view of the lock member 6 according to a first modified example. As illustrated in FIG. 9, the bulging portion may be omitted. The holding portion 46 and the resistance portion 47 are not limited to the protrusions, and may be a part of a rounded shape 61 provided in the groove portion 34. That is, the holding portion 46 and the resistance portion 47 may be disposed apart from each other by the rounded shape 61 provided in the groove portion 34.

[0044] FIG. 10 is an enlarged view of the lock member 6 according to a second modified example. As illustrated in FIG. 10, a straight portion 62 may be provided between the holding portion 46 and the resistance portion 47. That is, the holding portion 46 and the resistance portion 47 may be disposed apart from each other by the straight portion 62 provided in the groove portion 34.

[0045] FIG. 11 is an enlarged view of the lock member 6 according to a third modified example. As illustrated in FIG. 11, the first inner portion 44 and the second inner portion 45 are 2023437963   29 Jul 2026 not limited to a linear shape, and may have a bent shape. That is, the first inner portion 44 may include a first inclined surface 63 and a second inclined surface 64. The second inclined surface 64 may extend to the front side from the first inclined surface 63. The inclination angle of the second inclined surface 64 with respect to the front-rear direction may be larger than the inclination angle of the first inclined surface 63. Although not illustrated, the second inner portion 45 may have a shape symmetrical to the first inner portion 44. Although only the right portion of the lock member 6 is illustrated in FIGS. 9 to 11, the left portion of the lock member 6 of each modified example has a shape symmetrical to the right portion illustrated in FIGS. 9 to 11. Industrial Applicability

[0046] According to the present invention, the fixing structure for a replacement component in a work machine and a lock member, which enable reuse of the lock member and easy determination of engagement of the lock member are provided.

[0047] Reference Signs List 1: Fixing structure 4: Tooth (replacement component) 5: Pin member 6: Lock member 12: Attachment portion 15: First pin hole 34: Groove portion 2023437963   29 Jul 2026 35: Opening 41: Curved portion 42: First bulging portion 44: First inner portion 45: Second inner portion 46: Holding portion 47: Resistance portion 48, 49: First protrusion 51, 52: Second protrusion

Claims

1. A fixing structure for detachably fixing a replacement component in a work machine, the fixing structure comprising:an attachment portion including a pin hole and to which the replacement component is attached;a pin member disposed in the pin hole; anda lock member that engages with the pin member and prevents the pin member from coming off; whereinthe lock member includes:an opening;a groove portion that engages with the pin member, the groove portion extending from the opening;a holding portion that holds the pin member such that the pin member does not come off, the holding portion being provided in the groove portion; anda resistance portion that comes into contact with the pin member to give a tactile response when engaging with the pin member, the resistance portion being provided between the opening and the holding portion in the groove portion;the groove portion further includes:a curved portion that engages with the pin member;an inner portion inclined and extending from the opening toward the curved portion; anda bulging portion disposed between the curved portion and the inner portionand bulging to an inner side of the curved portion2023437963   29 Jul 2026the holding portion includes a pair of first protrusions disposed between the bulging portion and the curved portion; andthe resistance portion includes a pair of second protrusions disposed between the inner portion and the curved portion.

2. The fixing structure according to claim 1, wherein the holding portion is provided at the bulging portion.

3. The fixing structure according to claim 1, wherein the pair of first protrusions is disposed on opposite sides in the groove portion, andthe pair of second protrusions is disposed on opposite sides in the groove portion.

4. The fixing structure according to claim 3, wherein a width between the pair of second protrusions is narrower than a width between the pair of first protrusions.

5. The fixing structure according to claim 3, wherein the pin member includes a pin groove that is engaged with the lock member, and a width between the pair of second protrusions is smaller than an outer diameter of the pin groove.

6. A lock member that engages with a pin member that detachably fixes a replacement component in a work machine to prevent the pin member from coming off, the lock member comprising:an opening;a groove portion that engages with the pin member, the groove portion extending from the opening;a holding portion that holds the pin member such that the pin member does not come off, the holding portion being provided in the groove portion; and2023437963   29 Jul 2026a resistance portion that comes into contact with the pin member to give a tactile response when engaging with the pin member, the resistance portion being provided between the opening and the holding portion in the groove portion;the groove portion further includes:a curved portion that engages with the pin member;an inner portion inclined and extending from the opening toward the curved portion; anda bulging portion disposed between the curved portion and the inner portion and bulging to an inner side of the curved portionthe holding portion includes a pair of first protrusions disposed between the bulging portion and the curved portion; andthe resistance portion includes a pair of second protrusions disposed between the inner portion and the curved portion.

7. The lock member according to claim 6, wherein the holding portion is provided at the bulging portion.

8. The lock member according to claim 6, wherein the pair of first protrusions is disposed on opposite sides in the groove portion, andthe pair of second protrusions is disposed on opposite sides in the groove portion.

9. The lock member according to claim 8, wherein a width between the pair of second protrusions is narrower than a width between the pair of first protrusions.2023437963   29 Jul 202610. The lock member according to claim 8, wherein the pin member includes a pin groove that is engaged with the lock member, and a width between the pair of second protrusions is smaller than an outer diameter of the pin groove.

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