Work machine and attachment

Abstract

To provide a working machine capable of easily mounting an attachment to a boom on a working machine body side.SOLUTION: The working machine 2 includes a first boom 8 and a second boom 11. The second boom 11 is detachably attached to the first boom 8. The second boom 11 has a pair of side walls 42 and a pin 44. The pair of side wall portions 42 are disposed at the base end portion 46 attached to the first boom 8, and face each other in the width direction Y. The pin 44 is disposed between the pair of side wall portions 42. The first boom 8 has a locking part 24. The locking portion 24 is inserted between the pair of side wall portions 42 to lock the pin 44. The locking portion 24 has a pair of side surfaces 33. The pair of side surfaces 33 are disposed at both ends in the width direction Y. The side surface 33 has a first side surface portion 33a. The first side surface portion 33a is disposed on the distal end direction side of the first boom 8, and is formed so as to be located on the inner side in the widthwise direction toward the distal end direction.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a work machine and an attachment. [Background technology]

[0002] The working equipment of a work machine used to demolish buildings and the like is configured to be able to change multiple attachments depending on the working height and type of work (debris collection, loading, etc.) (see, for example, Patent Document 1).

[0003] For example, the work machine shown in Patent Document 1 is provided with an attachment such as a long demolition specification or a two-piece boom (separate boom) specification that can be attached to a base machine.

[0004] Each attachment has a boom at its base end, and the boom at the base end is detachably attached to another boom on the base machine, allowing multiple attachments to be interchangeably attached to the base machine. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-21434 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when attaching an attachment to the boom of the work machine body, it was difficult to attach it unless the work machine body and attachment were placed on a horizontal surface and furthermore, the work machine body and attachment were positioned in a straight line. Therefore, if the positioning of the work machine body and attachment was not appropriate, it took a long time to attach it.

[0007] An object of the present disclosure is to provide a work machine and an attachment that allow the attachment to be easily attached to a boom on the work machine body side. [Means for solving the problem]

[0008] In order to achieve the above object, a work machine of a first disclosure includes a first boom and a second boom. The second boom is detachably attached to the first boom. The second boom has a pair of side wall portions and an engaging portion. The pair of side wall portions are arranged at an end attached to the first boom and face each other in the width direction. The engaging portion is arranged between the pair of side wall portions. The first boom has an engaging portion. The engaging portion is inserted between the pair of side wall portions to engage the engaging portion. The engaging portion has a pair of side surfaces. The pair of side surfaces are arranged at both ends in the width direction. The side surfaces have a first side surface portion. The first side surface portion is arranged on the tip side of the first boom and is formed so as to be positioned inward in the width direction as it moves toward the tip.

[0009] The second disclosed attachment is an attachment including a second boom detachable from a first boom attached to a work machine body. The second boom has a pair of side wall portions, a locking portion, and a bushing. The pair of side wall portions are arranged at the end attached to the main body boom and face each other in the width direction. The locking portion is arranged between the side wall portions and is rod-shaped. The bushing is arranged around the locking portion and inside the side wall portions. The locking portion is locked when the locking portion of the main body boom is inserted between the pair of side wall portions. The locking portion has a notch portion, a positioning portion, and a pair of side surfaces. The locking portion can pass through the notch portion. The positioning portion is where the locking portion that has passed through the notch is positioned. The pair of side surfaces are arranged at both ends in the width direction. The pair of side surfaces have tip portions that are positioned inward in the width direction as they extend toward the insertion direction of the pair of side wall portions. The bushing faces the side surfaces when attached to the main body boom. The bushing has a flat surface portion and a corresponding shaped portion. The flat surface portion is arranged on the opposite side to the direction of movement when the first boom is moved upward relative to the second boom so that the locked portion passes through the notch. The corresponding shaped portion is arranged on the movement direction side so as to protrude more inward in the width direction than the flat surface portion, and has a shape corresponding to the side surface. [Effects of the Invention]

[0010] According to the present disclosure, it is possible to provide a work machine and an attachment that allows the attachment to be easily attached to the boom on the work machine body side. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a side view showing a work machine according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a side view showing a state in which the attachment has been detached from the first boom from the state shown in FIG. 1; [Figure 3] FIG. 2 is a perspective view showing the first boom and the second boom of FIG. 1. [Figure 4] FIG. 4 is an exploded perspective view of the first boom and the second boom of FIG. 3. [Figure 5]5(a) and (b) are perspective views showing the vicinity of the tip of the first boom in FIG. 4. FIG. [Figure 6] FIG. 5 is a plan view of the engaging portion of the first boom in FIG. 4; [Figure 7] FIG. 5 is a perspective view showing the vicinity of the base end portion of the second boom in FIG. 4. [Figure 8] 8A is a perspective view showing the vicinity of the bushing in FIG. 7, and FIG. 8B is a perspective view showing the bushing. [Figure 9] FIG. 10 is a side view showing the operation when the pin of the second boom is locked by the locking portion of the first boom. [Figure 10A] FIG. 10 is a diagram showing the positional relationship between the second boom and the first boom when attaching an attachment to the first boom. [Figure 10B] FIG. 10 is a diagram showing the positional relationship between the second boom and the first boom when attaching an attachment to the first boom. [Figure 10C] FIG. 10 is a diagram showing the positional relationship between the second boom and the first boom when attaching an attachment to the first boom. [Figure 11] FIG. 10 is a plan view showing a state in which the engaging portion of the first boom is inserted between a pair of side wall portions. [Figure 12] 5(a) to 5(c) are plan views schematically showing the insertion of the locking portion into a pair of side wall portions. [Figure 13] 10 is a schematic plan view illustrating insertion of a locking portion into a pair of side wall portions in a conventional configuration. FIG. [Figure 14] FIG. 10 is a plan view showing a state in which the locking portion locks the pin. [Figure 15] A diagram showing the attachment for the two-piece boom. [Figure 16] 10A and 10B are plan views showing a locking portion of a modified example of the embodiment according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0012] A working machine equipped with a working implement according to an embodiment of the present invention will be described below with reference to the drawings.

[0013] (composition) (Overall overview of the work machine) 1 is a side view showing a work machine 100 of this embodiment. The work machine 100 has a work machine main body 1 and a work implement 2.

[0014] The work machine main body 1 has a running body 3 and a rotating body 4. The running body 3 has a pair of tracks 3a, and the work machine 100 travels when the tracks 3a are driven by driving force from the engine.

[0015] The rotating unit 4 is mounted rotatably on the running unit 3. The rotating unit 4 has a cab 5, a storage room 6, a counterweight 7, etc. The cab 5 serving as a driver's cab is provided at the front left side of the rotating unit 4. The storage room 6 is provided behind the cab 5 and stores the engine, radiator, radiator fan, etc. The counterweight 7 is located at the rear of the rotating unit 4.

[0016] (Work machine 2) The work implement 2 has a first boom 8, a boom cylinder 9, and an attachment 10. The work implement 2 is attached to the front center position of the revolving unit 4, and the base end of the first boom 8 is rotatably connected to the revolving unit 4. The attachment 10 is detachably attached to the tip end of the first boom 8. Figure 2 is a side view showing the attachment 10 detached from the first boom 8.

[0017] The boom cylinder 9 has a tip of a rod 9a connected to the first boom 8 and a base end of a cylinder tube connected to the rotating body 4, and raises and lowers the first boom 8 by extending and contracting.

[0018] The attachment 10 is a long-length attachment for demolition work. The attachment 10 has a second boom 11, an intermediate link 12, an arm 13, a tip attachment (not shown), a first hydraulic cylinder 14, a second hydraulic cylinder 15, and a third hydraulic cylinder 16.

[0019] The second boom 11 is detachably attached to the tip of the first boom 8. One end of the intermediate link 12 is attached to the tip of the second boom 11 so as to be rotatable in the vertical direction. The tip of the rod of the first hydraulic cylinder 14 is connected to the intermediate link 12, and the base end of the cylinder tube is connected to the second boom 11.

[0020] The arm 13 has its base end attached to the other end of the intermediate link 12 so as to be rotatable in the vertical direction. The second hydraulic cylinder 15 has a rod tip connected to the arm 13 and a cylinder tube base end connected to the intermediate link 12.

[0021] A tip attachment (not shown) is attached to the tip of the arm 13 so as to be rotatable in the vertical direction. A crushing tool, a bucket, or the like is used as the tip attachment. The tip of the rod of the third hydraulic cylinder 16 is connected to the tip attachment, and the base end of the cylinder tube is connected to the arm 13.

[0022] The boom cylinder 9, the first hydraulic cylinder 14, the second hydraulic cylinder 15, and the third hydraulic cylinder 16 extend and retract to drive the work implement 2.

[0023] (Structure of the tip of the first boom 8) FIG. 3 is a perspective view showing a state in which the second boom 11 is attached to the first boom 8. FIG. 4 is a perspective view showing a state in which the second boom 11 has been detached from the first boom 8. In the following description, the term "inside of the work machine" refers to the center side of the work machine 2 when the work machine 2 is bent, for example, as shown in FIG. 1. The "inside of the work machine" corresponds to the lower side when the first boom 8 is lowered and the second boom 11 is positioned substantially horizontally as shown in FIG. 1. In the following specification, the term "outside of the work machine" refers to the outer periphery side of the work machine 2 when the work machine 2 is bent, as shown in FIG. 1. The "outside of the work machine" corresponds to the upper side when the first boom 8 is lowered and the second boom 11 is positioned substantially horizontally as shown in FIG. 3. In FIG. 3, the inside and outside of the work machine are indicated by arrows Xi and Xo, respectively. The width direction is indicated by Y, and the rightward direction within the width direction Y is indicated by Yr and the leftward direction is indicated by Yl. Furthermore, within the longitudinal direction Z of the first boom 8, the direction toward the tip side (the side to which the second boom 11 is connected) is indicated as the tip direction Za, and the direction toward the work machine body 1 is indicated as the base direction Zb.

[0024] 3 and 4, the first boom 8 has a first boom body 21, a pair of brackets 22, a connecting portion 23, and a locking portion 24. The first boom body 21 has a base end portion 25 rotatably attached to the revolving unit 4, a tip end portion 26 to which the second boom 11 is detachably attached, and a connection portion 27 to which the tip of the rod 9a of the boom cylinder 9 is connected. The connection portions 27 are provided on side surfaces 21a on both sides of the first boom body 21 in the width direction Y. The boom cylinders 9 are arranged on both sides of the first boom 8 in the width direction Y.

[0025] Each bracket 22 is provided on the side surface 21a on both sides in the width direction Y, closer to the tip portion 26 than the connecting portion 27. As shown in FIG. 4, the bracket 22 is fixed to the side surface 21a at its base portion 221, and the base portion 221 is located near the tip portion 26 side of the connecting portion 27. The bracket 22 extends from the base portion 221 toward the tip portion 26 along the first boom main body 21. An end portion 222 of the bracket 22 on the tip portion 26 side is located with a predetermined space between it and the side surface 21a of the first boom main body 21. An inner end portion 421 of a side wall portion 42 of the second boom 11, which will be described later, is located in the space between this end portion 222 and the side surface 21a.

[0026] 5(a) and 5(b) are perspective views showing the vicinity of tip 26 of first boom 8. Connecting portion 23 is disposed at the end of first boom 8 on the inside of the work machine (the side of arrow X1). Connecting portion 23 connects to connected portion 43 of second boom 11.

[0027] The connecting portion 23 has a first through hole 231 and a second through hole 232. The first through hole 231 is formed in the first boom body 21 along the width direction Y. The second through hole 232 is formed in the end portion 222 on the tip portion 26 side of each bracket 22. The second through hole 232 is formed along the width direction Y. The central axes of the first through hole 231 and the second through hole 232 are coaxial. Although not shown, a hydraulic expansion / contraction pin that expands and contracts hydraulically is disposed in the first through hole 231, and expansion of the hydraulic expansion / contraction pin connects the connecting portion 23 of the first boom 8 to the connected portion 43 of the second boom 11.

[0028] As shown in Figures 5(a) and 5(b), the locking portion 24 is disposed at the tip end 26 of the first boom body 21. As shown in Figure 3, the locking portion 24 locks onto a pin 44 (an example of a locked portion) of the second boom 11. The locking portion 24 supports the pin 44 from below.

[0029] The locking portion 24 is formed along the width direction Y at the end of the tip portion 26 of the first boom body 21 on the outer side of the work machine (the side of the arrow X2). The connecting portion 23 is disposed closer to the base end direction Zb than the locking portion 24.

[0030] As shown in Figures 5(a) and 5(b), the locking portion 24 has a cutout portion 31, a placement portion 32, and a pair of side surfaces 33. The locking portion 24 has a generally cylindrical shape with the cutout portion 31 formed along the width direction Y. The cutout portion 31 is provided on the locking portion 24 on the outer side of the work machine (the side indicated by arrow X2). The cutout portion 31 is formed to allow the pin 44 of the second boom 11 to pass through. The placement portion 32 is inside the locking portion 24 and is a cylindrical space having an axis along the width direction Y. The pin 44 of the second boom 11 that has passed through the cutout portion 31 is placed in the placement portion 32.

[0031] The pair of side surfaces 33 are arranged on both ends of the locking portion 24 in the width direction Y. The side surfaces 33 form the side surfaces of the locking portion 24. As shown in FIG. 5(b), the side surfaces 33 are arranged around an opening 32a facing outward in the width direction of the arrangement portion 32, and are cut out by an opening 31a facing outward in the width direction Y of the cutout portion 31.

[0032] Fig. 6 is a plan view of the locking portion 24. As shown in Fig. 6, the side surface 33 on the right side Yr in the width direction Y and the side surface 33 on the left side Yl are each formed into a spherical shape. The side surface 33 on the right side Yr is formed into a spherical shape centered at a position P1 located on the central axis O of the arrangement portion 32. This spherical surface Q1 is indicated by a two-dot chain line. The left side surface 33 is formed into a spherical shape centered at a position P2 located on the central axis O. This spherical surface Q2 is indicated by a two-dot chain line.

[0033] In FIG. 6, a portion of the side surface 33 located closer to the distal direction Za than the central axis O is shown as a first side surface portion 33a. A portion of the side surface 33 located closer to the proximal direction Zb than the central axis O is shown as a second side surface portion 33b. The first side surface portion 33a is the portion on the distal direction Za side of the openings 31a, 32a. The second side surface portion 33b is the portion on the proximal direction Zb side of the openings 31a, 32a. The first side surface portion 33a is formed so as to be positioned more inward in the width direction Y as it extends toward the distal direction Za. The second side surface portion 33b is formed so as to be positioned more inward in the width direction Y as it extends toward the proximal direction Zb. The side surface 33 is formed so as to be curved convexly outward in the width direction Y along the insertion direction B.

[0034] The locking portion 24 also has a pair of side portions 34 and an intermediate portion 35. The outer surface of each side portion 34 in the width direction Y is the side surface 33. The intermediate portion 35 is disposed between the pair of side portions 34. The intermediate portion 35 connects the pair of side portions 34. The pair of side portions 34 and the intermediate portion 35 are connected by welding, for example. The portion of the intermediate portion 35 of the cutout portion 31 is formed larger than the portion of the side portions 34. The portion of the intermediate portion 35 of the placement portion 32 is formed larger than the portion of the side portions 34. The pin 44 of the second boom 11 is locked by the pair of side portions 34 of the locking portion 24.

[0035] (Structure of the base end of the second boom 11) 7 is an enlarged view of the vicinity of the base end 46 (an example of an end) of the second boom 11. The second boom 11 has a second boom main body 41, a pair of side wall portions 42, a connected portion 43, a pin 44, and a pair of bushings 45. The second boom main body 41 is attached to the first boom 8 via the pair of side wall portions 42 and the pin 44. As shown in FIG. 4, the second boom main body 41 has a base end 46 on the first boom 8 side and a tip end 47 on the intermediate link 12 side.

[0036] The pair of side wall portions 42 are disposed at the base end portion 46 of the second boom main body 41. The pair of side wall portions 42 protrude from the base end portion 46. Each side wall portion 42 is connected to a side surface 41a of the second boom main body 41 in the width direction Y. Each side wall portion 42 is generally plate-shaped and disposed perpendicular to the width direction Y. The side wall portion 42 on the right side (Yr side) protrudes from the side surface 41a on the right side (Yr side). The side wall portion 42 on the left side (Yl side) protrudes from the side surface 41a on the left side (Yl side).

[0037] The connected portion 43 is connected to the connecting portion 23 of the first boom 8. The connected portion 43 is arranged at the inner end portion 421 on the inner direction Xi side of each side wall portion 42. The connected portion 43 has a pair of through holes 431. Each through hole 431 is formed in each side wall portion 42. The through holes 431 penetrate the side wall portion 42 along the width direction Y. The through hole 431 formed in the side wall portion 42 on the left direction Yl side and the through hole 431 formed in the side wall portion 42 on the right direction Yr side have their central axes aligned along the width direction Y and are coaxial.

[0038] The pin 44 is disposed between the pair of side wall portions 42 along the width direction Y. Both ends of the pin 44 are fixed to the side wall portions 42. The pin 44 is fixed to an outer end portion 422 on the outer side in the outward direction Xo of each side wall portion 42. The pin 44 is disposed closer to the tip portion 47 than the connected portion 43.

[0039] The pair of bushings 45 are arranged inside each side wall portion 42. FIG. 8(a) is a diagram showing the configuration in the vicinity of the right bushing 45. FIG. 8(b) is a perspective view showing the configuration of the bushing 45. The pair of bushings 45 are arranged line-symmetrically with respect to the central axis of the second boom 11. A through hole 45a into which the pin 44 is inserted is formed in the bushing 45. The bushing 45 is arranged around the pin 44.

[0040] As shown in FIGS. 8(a) and 8(b), the bushing 45 has a flat portion 51 and a corresponding shaped portion 52. The flat portion 51 is disposed parallel to the side wall portion 42. The corresponding shaped portion 52 protrudes inward in the width direction Y beyond the flat portion 51. The corresponding shaped portion 52 has an inner surface 52a formed into a curved surface that corresponds to the side surface 33 of the locking portion 24. The inner surface 52a is formed into a curved surface that corresponds to a spherical surface.

[0041] 8(b), approximately half of the bushing 45 is the flat portion 51, and the remaining portion is the corresponding shape portion 52. The flat portion 51 is the portion of the bushing 45 that is approximately on the side of the through hole 431. The corresponding shape portion 52 is the portion of the bushing 45 that is approximately on the opposite side from the through hole 431.

[0042] The arrangement of the corresponding shape portion 52 and the flat portion 51 will be further described. Figure 9 is a diagram showing the operation when the pin 44 of the second boom 11 is locked by the locking portion 24 of the first boom 8. In Figure 9, the left side wall portion 42 is omitted.

[0043] As will be described in more detail below, by moving the first boom 8 upward relative to the second boom 11, the pin 44 passes through the cutout 31 and is placed in the placement section 32, where it is locked by the locking section 24. Here, the direction in which the locking section 24 moves due to the upward rotation of the first boom 8 is indicated by arrow A.

[0044] The corresponding shape portion 52 is formed on a portion of the bushing 45 on the side of the movement direction A. The flat portion 51 is formed on a portion of the bushing 45 on the opposite side of the movement direction A. In FIG. 9 , for ease of understanding, the corresponding shape portion 52 of the bushing 45 is hatched. By forming the flat portion 51 on the portion of the bushing 45 on the opposite side of the movement direction A in this way, it is possible to prevent the bushing 45 from abutting against the side surface 33 of the locking portion 24 when the locking portion 24 moves to lock the pin 44, thereby preventing the movement of the locking portion 24 from being hindered.

[0045] (Installation operation) Next, the mounting operation for mounting the attachment 10 on the first boom 8 will be described.

[0046] 10A to 10C are diagrams showing the positional relationship between the second boom 11 and the first boom 8 during the operation of attaching the attachment 10 to the first boom 8. FIG.

[0047] As shown in Fig. 2, with the attachment 10 placed on the ground or a platform, the work machine main body 1 equipped with the first boom 8 moves toward the attachment 10 (see arrow B). As shown in Fig. 10A, the locking portion 24 of the first boom 8 is inserted between a pair of side wall portions 42 of the second boom 11. The insertion direction B of the first boom 8 is a direction that generally coincides with the longitudinal direction of the first boom 8.

[0048] FIG. 11 is a plan view showing the state in which the locking portion 24 is inserted between a pair of side wall portions 42. In this embodiment, the side surface 33 of the locking portion 24 is formed in a spherical shape. In FIG. 11, the second boom 11 and the first boom 8 are not arranged in a straight line. More specifically, the central axis 8a of the first boom 8 and the central axis 11a of the second boom 11 are not arranged in a straight line but are misaligned. Even in such a case, in the work machine 2 of this embodiment, the side surface 33 of the locking portion 24 is formed in a spherical shape, so the locking portion 24 can be inserted between the pair of side wall portions 42.

[0049] 12(a) to 12(c) are plan views showing the insertion of the locking portion 24 into the pair of side wall portions 42 in this embodiment. For ease of understanding, for example, the inner end portion 421 and the like are omitted from FIGS. 12(a) to 12(c).

[0050] Figure 12(a) is a diagram showing a state in which the locking portion 24 is inserted between a pair of side wall portions 42. In Figure 12(a), the central axis 8a of the first boom 8 and the central axis 11a of the second boom 11 are arranged on a straight line.

[0051] Figure 12(b) is a diagram showing a state before the locking portion 24 is inserted between the pair of side wall portions 42. In the state shown in Figure 12(b), similar to Figure 11, the central axis 8a of the first boom 8 and the central axis 11a of the second boom 11 are not arranged on a straight line, and the central axis 8a of the first boom 8 is tilted relative to the central axis 11a of the second boom 11.

[0052] 12(b), because the side surface 33 has a spherical shape, the side surface 33 has a circular shape in a plan view, and the width perpendicular to the central axis 8a of the locking portion 24 is approximately the same as the width perpendicular to the central axis 11a of the locking portion 24. Therefore, even if the locking portion 24 is moved relative to the side wall portions 42 along the insertion direction B in a state in which the central axes 8a and 11a are not aligned as shown in FIG. 12(b), the locking portion 24 can be inserted between the side wall portions 42 as shown in FIG.

[0053] 13 is a schematic plan view illustrating insertion of the locking portion 1024 into a pair of side wall portions 1042 in a conventional configuration. In FIG. 13, the side surface 1033 of the locking portion 1024 is not spherical, but is formed parallel to the central axis 1008a of the first boom 1008. In the conventional configuration, if the central axis 1008a of the first boom 1008 and the central axis 1011a of the second boom 1011 are not aligned, the width of the locking portion 1024 perpendicular to the central axis 1011a is longer than the width of the locking portion 1024 perpendicular to the central axis 1008a. Therefore, when the locking portion 1024 is moved relative to the pair of side wall portions 1042 in the direction of arrow B, for example, portion P1000 of the locking portion 1024 interferes with the side wall portions 1042, making it impossible to insert the locking portion 1024 between the side wall portions 1042.

[0054] As described above, in the work implement 2 of this embodiment, even if the second boom 11 and the first boom 8 are not arranged in a straight line, the side surface 33 of the locking portion 24 is formed into a spherical shape, so that the locking portion 24 can be inserted between the pair of side wall portions 42. Furthermore, in the work implement 2 of this embodiment, because the side surface 33 is spherical, the side surface 33 is circular in the work implement inward direction Xi and the work implement outward direction Xo (the up-down direction when attached). Therefore, as described above, even if the central axis O of the arrangement portion 32 is slightly inclined with respect to the width direction of the second boom 11, the locking portion 24 can be easily inserted between the side wall portions 42.

[0055] Next, from the state shown in Fig. 10A, boom cylinder 9 is extended, and first boom 8 rotates upward (see arrow A in Fig. 10A). As a result, pin 61 of second boom 11 is placed in positioning portion 32 through notch 31 of locking portion 24, and is locked by locking portion 24.

[0056] Here, a corresponding shape portion 52 is formed on the bushing 45 on the side of the movement direction A of the locking portion 24. Therefore, as the locking portion 24 moves toward the pin 44, the side surface 33 of the locking portion 24 slides against the corresponding shape portion 52, so that the central axis O of the locking portion 24 in the width direction and the central axis of the pin 44 coincide with each other, thereby aligning them. FIG. 14 is a plan view showing the state in which the locking portion 24 has locked the pin 44. As shown in FIG. 14, this alignment positions the central axis 11a of the second boom 11 and the central axis 8a of the first boom 8 on a straight line. Furthermore, because the bushing 45 has the corresponding shape portion 52, even if a force acts on the locking portion 24 in the width direction Y, the force can be received by the bushing 45.

[0057] 10B, the boom cylinder 9 is further extended, and the first boom 8 moves upward (see arrow A). When the first boom 8 moves upward in this manner, the second boom 11 moves toward the first boom 8 side, with the pin 44 as a fulcrum (see arrow C).

[0058] By rotating the second boom 11 toward the first boom 8, the inner end 421 of the side wall portion 42 of the second boom 11 is inserted into the space between the side surface 21a of the first boom main body 21 and the end 222 of the bracket 22.

[0059] 10C , once the alignment of the through hole 431 of the side wall portion 42 with the first through hole 231 and the second through hole 232 is complete, the hydraulic expansion / contraction pin arranged in the first through hole 231 extends and is inserted into the through hole 431 and the second through hole 232. This connects the connecting portion 23 of the first boom 8 to the connected portion 43 of the second boom 11, completing the attachment of the second boom 11 to the first boom 8.

[0060] To remove the attachment 10 from the first boom 8, the above operations are performed in reverse. The hydraulic expansion / contraction pin is contracted to release the connection between the connecting portion 23 and the connected portion 43, and the first boom 8 is rotated downward to place the attachment 10 on the ground or a pedestal. After that, the first boom 8 is rotated downward further to release the locking of the pin 44 by the locking portion 24, and the first boom 8 is moved in the direction opposite to the insertion direction B, and the locking portion 24 is pulled out from between the pair of side wall portions 42. This allows the attachment 10 to be removed from the first boom 8.

[0061] (Features, etc.) In the work implement 2 of this embodiment, the side surface 33 of the locking portion 24 of the first boom 8, which is inserted between the pair of side wall portions 42 of the second boom 11, is formed into a spherical surface. As a result, even if the first boom 8 and the second boom 11 are positioned slightly off-center from a straight line, the locking portion 24 can be easily inserted between the pair of side wall portions 42, making it easy to attach the attachment 10 to the first boom 8. Furthermore, even if the central axis O of the positioning portion 32 is slightly inclined with respect to the width direction of the second boom 11, the locking portion 24 can be easily inserted between the side wall portions 42.

[0062] In the work implement 2 of this embodiment, a bushing 45 is disposed inside the side wall portion 42 around the pin 44. The bushing 45 has a flat portion 51 and a corresponding-shaped portion 52. The flat portion 51 is disposed on the side opposite the direction of movement A when the first boom 8 is moved upward relative to the second boom 11 so that the pin 44 passes through the cutout portion 31. The corresponding-shaped portion 52 is disposed on the direction of movement A side so as to protrude inward in the width direction Y from the flat portion 51, and corresponds to the shape of the side surface 33. As a result, the side surface 33 of the locking portion 24 slides over the corresponding-shaped portion 52, thereby aligning the central axis O of the locking portion 24 in the width direction with the central axis of the pin 44. This alignment aligns the central axis 11a of the second boom 11 and the central axis 8a of the first boom 8 on a straight line. This makes it easy to attach the attachment 10 to the first boom 8 even if the first boom 8 and the second boom 11 are slightly misaligned.

[0063] (Other embodiments) Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the gist of the present disclosure.

[0064] (A) In the above embodiment, a long demolition attachment 10 was used as the attachment to be attached to the first boom 8, but this is not limited to the long demolition attachment, and a short, excavation, or two-piece boom attachment may also be used.

[0065] 15 is a diagram showing a two-piece boom attachment 200. The attachment 200 has a second boom 211, an arm 212, a tip attachment (not shown), a first hydraulic cylinder 214, a second hydraulic cylinder 215, and a third hydraulic cylinder 216.

[0066] The second boom 211 has a bracket 217 and a second boom body 218 . The bracket 217 is attached to the base end 246 of the second boom body 218. The bracket 217 is detachably attached to the first boom 8. In this specification, the boom includes a bracket disposed at the base end of the boom body. The first hydraulic cylinder 214 has a rod end connected to the second boom body 218 and a cylinder tube end connected to the bracket 217.

[0067] The arm 212 is rotatably attached to the tip of the second boom 211. The second hydraulic cylinder 215 has a rod end connected to the arm 212 and a cylinder tube end connected to the second boom main body 218. A tip attachment (not shown) is rotatably attached to the tip of the arm 212. The third hydraulic cylinder 216 has a rod end connected to the tip attachment and a cylinder tube end connected to the arm 212.

[0068] The bracket 217 has a pair of side wall portions 242, a connectable portion 243, a pin 244, and a bushing (not shown). The side wall portion 242 corresponds to the side wall portion 42 in the above embodiment, the pin 244 corresponds to the pin 44 in the above embodiment, and the bushing corresponds to the bushing 45 in the above embodiment. The connectable portion 243 has a through hole 243a formed in the side wall portion 242. The connectable portion 243 is connected to the connecting portion 23 of the first boom 8. The pin 244 is engaged with the engaging portion 24 of the first boom 8. The second boom 211 of the attachment 200 is attached to the first boom 8 by engaging the pin 244 with the engaging portion 24 of the first boom 8 and connecting the connectable portion 243 with the connecting portion 23.

[0069] (B) In the working machine 2 of the above embodiment, the side surface 33 of the locking portion 24 is formed in a spherical shape, but it is not limited to a spherical shape and may be a curved surface other than a spherical surface or may be tapered. For example, the first side surface portion 33a of the locking portion 24 may be formed so as to be positioned inward in the width direction Y as it extends toward the tip end direction Za of the longitudinal direction Z, and may be tapered. The second side surface portion 33b of the locking portion 24 may be formed so as to be positioned inward in the width direction Y as it extends toward the base end direction Zb of the longitudinal direction Z. Furthermore, the second side surface portion 33b may be formed parallel to the longitudinal direction Z.

[0070] Fig. 16(a) is a plan view showing a modified locking portion 24'. As shown in Fig. 16(a), on a side surface 33' of the locking portion 24', a first side surface portion 33a' on the distal direction Za side is formed in a tapered shape that is positioned inward in the width direction Y as it extends toward the distal direction Za. Furthermore, a second side surface portion 33b' on the proximal direction Zb side is formed in a tapered shape that is positioned inward in the width direction Y as it extends toward the proximal direction Zb.

[0071] FIG. 16(b) is a plan view showing a modified locking portion 24''. In the locking portion 24'', the second side surface portion 33b'' of the side surface 33'' is formed parallel to the longitudinal direction Z, unlike the locking portion 24'. Even in this type of locking portion 24'', at least the tip side is tapered, making it easier to insert between the pair of side wall portions 42.

[0072] (C) In the above embodiment, the bushing 45 has the flat portion 51 and the corresponding shaped portion 52, but the bushing 45 may not be provided with the corresponding shaped portion 52 and may have only the flat portion 51. Even in this case, it becomes easier to insert the locking portion 24 between the pair of side wall portions 42.

[0073] (D) In the above embodiment, the locking portion 24 is configured by connecting a pair of side portions 34 and the middle portion 35, but it may also be formed from a single member.

[0074] (E) In the above embodiment, the working machine 100 with dismantling specifications has been described as an example, but it is not limited to dismantling specifications and can be applied to any working machine that is interchangeable with a plurality of attachments. [Industrial Applicability]

[0075] The working machine and attachment of the present invention have the effect of making it possible to easily mount an attachment to the boom on the working machine body, and are useful as a working machine with demolition specifications, etc. [Explanation of symbols]

[0076] 2: Work equipment 8: First boom 11: Second boom 24: Locking part 33: Side 33a: 1st side part 42: Side wall 44: Pin

Claims

1. a first boom and a second boom detachably attached to the first boom, The second boom is a pair of side wall portions disposed at an end attached to the first boom and facing each other in a width direction; a locking portion disposed between the side wall portions, the first boom has a locking portion that is inserted between the pair of side wall portions and locks the locked portion, The locking portion has a pair of side surfaces arranged at both ends in the width direction, the side surface has a first side surface portion that is disposed on a tip direction side of the first boom and is formed to be positioned inward in the width direction as it extends toward the tip direction, Work equipment.

2. the side surface has a second side surface portion that is disposed on a base end direction side opposite to the tip end direction of the first side surface portion and is formed so as to be positioned inward in the width direction as it extends toward the base end direction; The work machine according to claim 1 .

3. The side surface is formed into a curved surface that is convexly curved outward in the width direction, the first side surface portion is a portion of the curved surface on the insertion direction side, The second side surface portion is a portion of the curved surface on the proximal direction side. The work machine according to claim 2.

4. The curved surface is a spherical surface. The work machine according to claim 3.

5. The locked portion is rod-shaped, The locking portion has a notch portion through which the locked portion can pass, and an arrangement portion in which the locked portion that has passed through the notch portion is arranged. The work machine according to claim 1 .

6. the second boom further includes a bushing that is disposed around the engaged portion and inside the side wall portion and faces the side surface, The bushing is a flat surface portion disposed on an opposite side to a moving direction of the engaging portion when the first boom is moved upward relative to the second boom so that the engaged portion passes through the notch portion; a corresponding shape portion that is disposed in the movement direction so as to protrude inward in the width direction from the flat portion, and has a shape corresponding to the side surface, The work machine according to claim 5.

7. The side surface is formed into a curved surface that is convexly curved outward in the width direction, the first side surface portion is a portion of the curved surface on the insertion direction side, The corresponding shape portion is formed into a curved surface corresponding to the curved surface. The work machine according to claim 6.

8. the second boom further includes a connected portion that is disposed at the end portion and is positioned below the engaged portion when attached to the first boom, The first boom further includes a connecting portion connected to the connected portion. A work machine according to any one of claims 1 to 7.

9. An attachment including a second boom detachable from a first boom attached to a work machine body, The second boom is a pair of side wall portions disposed at an end attached to the first boom and facing each other in a width direction; a rod-shaped locked portion disposed between the side wall portions; a bushing disposed around the locked portion and inside the side wall portion, the engaged portion is engaged with the engaging portion of the first boom inserted between the pair of side wall portions, the engaging portion has a cutout portion through which the engaged portion can pass, an arrangement portion in which the engaged portion that has passed through the cutout portion is arranged, and a pair of side surfaces arranged at both ends in the width direction, the side surfaces having a first side surface portion that is arranged on the tip side of the first boom and is formed so as to be positioned inward in the width direction as it extends toward the tip side, the bushing faces the side surface when attached to the first boom, The bushing is a flat surface portion disposed on an opposite side to a moving direction when the first boom is moved upward relative to the second boom so that the engaged portion passes through the notch portion; a corresponding shape portion that is disposed in the movement direction so as to protrude inward in the width direction from the flat portion, and has a shape corresponding to the side surface, attachment.

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