Work machine

Abstract

To provide a work machine capable of appropriately limiting the rotation range of a hook device.SOLUTION: A work machine comprises: a hook device equipped with a hook side stopper for limiting a rotation range; a connecting link equipped with a first connecting portion rotatably connected to a quick coupler and the hook device, a second connecting portion rotatably connected to a tip of an attachment cylinder, and a link side stopper provided on an outer peripheral surface of the first connecting portion and abutting against the hook side stopper when the hook device is rotated to a predetermined position; and an adjustment member for adjusting an abutment position of the hook side stopper and the link side stopper in the circumferential direction of the first connecting portion.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a work machine equipped with a hook device and a quick coupler. [Background technology]

[0002] Conventionally, there are known work machines equipped with quick couplers to simplify the task of changing attachments according to the work application, and work machines that can perform lifting work by attaching a hook to the bucket link. These work machines can perform multiple types of work with a single machine, such as changing attachments and performing lifting work with a hook.

[0003] Some work machines equipped with both a quick coupler and a hook are provided with a stopper that limits the rotation range of the hook to prevent the hook from interfering with the quick coupler during lifting work (see, for example, Patent Document 1). More specifically, in Patent Document 1, the rotation range of the hook is limited by abutting a protrusion provided on the hook side against a stopper provided on the bucket link. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2003-095577 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in Patent Document 1, there is a possibility that the rotation range of the hook cannot be appropriately limited due to manufacturing errors, installation errors, and deterioration over time (eg, wear) of either or both of the protrusion and the stopper.

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide a work machine that is capable of appropriately limiting the rotation range of a hook device. [Means for solving the problem]

[0007] In order to achieve the above object, the present invention provides a work machine comprising a vehicle body, a boom connected to the vehicle body so as to be able to be raised and lowered, an arm connected to a tip of the boom so as to be rotatable, a quick coupler connected to a tip of the arm so as to be rotatable, an attachment detachably engaged with the quick coupler, an attachment cylinder which rotates the quick coupler relative to the arm, a hook device which suspends a load from the tip side of the arm, and a connecting link which rotatably connects the quick coupler, the attachment cylinder, and the hook device. the hook device is provided with a hook side stopper for limiting a rotation range, the connecting link is provided with a first connecting portion rotatably connected to the quick coupler and the hook device, a second connecting portion rotatably connected to the tip of the attachment cylinder, and a link side stopper provided on the outer circumferential surface of the first connecting portion and abutting against the hook side stopper when the hook device is rotated to a predetermined position, and further includes an adjustment member for adjusting the abutment position of the hook side stopper and the link side stopper in the circumferential direction of the first connecting portion. Effect of the Invention

[0008] According to the present invention, the rotation range of the hook device can be appropriately limited. Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a side view of a hydraulic excavator according to the present invention. [Diagram 2] FIG. 2 is an exploded perspective view of the hook device and the first link. [Diagram 3] 4A and 4B are side views of a hook device and a first link, in which FIG. 4A shows the working position of the hook device and FIG. 4B shows the stored position of the hook device. [Figure 4] FIG. [Diagram 5] 13A and 13B are diagrams illustrating modified examples of the adjustment member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An embodiment of a work machine according to the present invention will be described with reference to the drawings. Fig. 1 is a side view of a hydraulic excavator 1 according to the present invention. In this specification, front, rear, left and right are based on the viewpoint of an operator who is on board and operating the hydraulic excavator 1, unless otherwise specified.

[0011] [Configuration of hydraulic excavator 1] The hydraulic excavator 1 includes a lower traveling body 2 and an upper rotating body 3 supported by the lower traveling body 2. The lower traveling body 2 and the upper rotating body 3 are an example of a vehicle body. The lower traveling body 2 includes a pair of left and right crawlers. When the rotation of a traveling motor (not shown) is transmitted to rotate the pair of left and right crawlers, the hydraulic excavator 1 travels. However, the lower traveling body 2 may be of a wheel type instead of a crawler type.

[0012] The upper rotating body 3 is rotatably supported by the lower traveling body 2. The upper rotating body 3 mainly comprises a rotating frame 5 serving as a base, a cab (driver's seat) 7 arranged on the front left side of the rotating frame 5, a front working implement 10 attached to the center of the front end of the rotating frame 5 so as to be rotatable in the vertical direction, and a counterweight 6 arranged at the rear of the rotating frame 5 to balance the weight of the front working implement 10.

[0013] The cab 7 defines an internal space in which an operator who operates the hydraulic excavator 1 sits. A seat (not shown) on which the operator sits, and operation devices (e.g., a steering wheel, pedals, levers, switches, etc.) operated by the operator seated in the seat are arranged inside the cab 7. When the operator seated in the cab 7 operates the operation devices, the lower traveling body 2 travels, the upper rotating body 3 rotates, and the front working implement 10 operates.

[0014] The front working implement 10 is supported by the upper rotating body 3 and performs various operations (for example, excavation work, demolition work, and lifting work). The front working implement 10 mainly comprises a boom 11, an arm 12, a quick coupler 13, a bucket 14 (attachment), a boom cylinder 15, an arm cylinder 16, an attachment cylinder 17, a hook device 20, a first link 30 (connecting link), and a pair of second links 40.

[0015] The boom 11 is connected to the upper rotating body 3 so as to be rotatable (raised and lowered) around a pin (not shown) extending in the left-right direction (width direction of the upper rotating body 3). One end (cylinder tube side) of the boom cylinder 15 is rotatably supported by the upper rotating body 3, and the other end (cylinder rod side) is rotatably supported by the boom 11. The boom 11 stands up when the boom cylinder 15 extends, and is lowered when the boom cylinder 15 retracts.

[0016] The arm 12 is connected to the tip of the boom 11 so as to be rotatable around a pin (not shown) extending in the left-right direction. One end (cylinder tube side) of the arm cylinder 16 is rotatably supported by the boom 11, and the other end (cylinder rod side) is rotatably supported by the arm 12. When the arm cylinder 16 extends, the tip of the arm 12 rotates in a direction (rearward, downward) approaching the upper rotating body 3, and when the arm cylinder 16 contracts, the tip rotates in a direction (forward, upward) away from the upper rotating body 3.

[0017] The quick coupler 13 is rotatably connected to the tip of the arm 12 around a pin 41 extending in the left-right direction, and is rotatably connected to the first link 30 around a pin 42 extending in the left-right direction. The quick coupler 13 also detachably engages the bucket 14. The quick coupler 13 rotates integrally with the bucket 14 around the pin 41 as the attachment cylinder 17 extends and retracts.

[0018] One end (cylinder tube side) of the attachment cylinder 17 is rotatably supported on the base end side of the arm 12, and the other end (cylinder rod side) is rotatably connected to the first link 30 and the second link 40 around a pin 43 extending in the left-right direction. The attachment cylinder 17 rotates the quick coupler 13 relative to the arm 12. More specifically, when the attachment cylinder 17 extends, the quick coupler 13 rotates in a direction in which the bucket approaches the abdominal surface of the arm 12, and when the attachment cylinder 17 contracts, the quick coupler 13 rotates in a direction in which the bucket moves away from the abdominal surface of the arm 12.

[0019] The bucket 14 is supported by the quick coupler 13 so as to be detachable. In addition, specific examples of the attachment are not limited to the bucket 14, and may be a grapple, a cutter, a breaker, etc. Here, "detachable" means that the bucket 14 can be easily attached and detached at the work site by extending and contracting the boom cylinder 15, the arm cylinder 16, and the attachment cylinder 17 in a predetermined order. More specifically, the quick coupler 13 has hooks that engage pins 14a, 14b that are attached to the bucket 14 and extend in the left-right direction. The structure for engaging the bucket 14 with the quick coupler 13 is already well known, so a detailed description will be omitted.

[0020] The hook device 20 is connected to the first link 30 so as to be rotatable around the pin 42. In other words, the hook device 20 is rotatably supported at the tip of the arm 12 (in other words, between the arm 12 and the quick coupler 13) via the first link 30. The hook device 20 is configured so as to be able to suspend a load. The configuration of the hook device 20 will be described later with reference to Figs. 2 and 3.

[0021] The first link 30 rotatably connects the quick coupler 13, the other end (tip) of the attachment cylinder 17, the hook device 20, and the pair of second links 40. More specifically, the first link 30 is rotatably connected to the quick coupler 13 and the hook device 20 via a pin 42. The first link 30 is also rotatably connected to the other end of the attachment cylinder 17 and the pair of second links 40 via a pin 43. The configuration of the first link 30 will be described later with reference to Figures 2 and 3.

[0022] The pair of second links 40 are long rod-shaped members. One end of each of the pair of second links 40 is rotatably connected to the other end of the attachment cylinder 17 and the first link 30 via a pin 43. The other end of each of the pair of second links 40 is rotatably connected to the tip of the arm 12 via a pin 44 extending in the left-right direction.

[0023] [Configuration of hook device 20 and first link 30] Fig. 2 is an exploded perspective view of the hook device 20 and the first link 30. Fig. 3 is a side view of the hook device 20 and the first link 30, in which (A) shows the hook device 20 in a working position and (B) shows the hook device 20 in a stored position.

[0024] 2 and 3, the hook device 20 mainly comprises a hook body 21 for suspending a load, and a bracket 22 for connecting the hook body 21 to the first link 30 so as to be rotatable about two axes (pins 25 and 26 described below). The bracket 22 is composed of a first bracket 23 and a second bracket 24.

[0025] The first bracket 23 includes a cylindrical portion 23a, a pair of first support portions 23b, 23c, and a hook side stopper 23d. The cylindrical portion 23a is a cylindrical portion through which the pin 42 is inserted. The pair of first support portions 23b, 23c protrude radially outward from the outer circumferential surface of the cylindrical portion 23a. The pair of first support portions 23b, 23c are arranged spaced apart in the left-right direction. The first support portions 23b, 23c support the pin 25 extending in the left-right direction. The hook side stopper 23d is arranged on the outer circumferential surface of the cylindrical portion 23a at a position circumferentially shifted from the first support portions 23b, 23c. The hook side stopper 23d abuts against a link side stopper 38, which will be described later, thereby limiting the rotation range of the hook device 20.

[0026] The second bracket 24 has a pin insertion hole 24a and a pair of second support portions 24b, 24c. A pin 25 is inserted into the pin insertion hole 24a. This allows the second bracket 24 to be rotatably connected to the first bracket 23 around the pin 25. The pair of second support portions 24b, 24c are spaced apart in a direction perpendicular to the left-right direction. The second support portions 24b, 24c support a pin 26 extending in a direction perpendicular to the left-right direction.

[0027] Hook body 21 is connected to second bracket 24 so as to be rotatable around pin 26. As a result, hook body 21 is supported by bracket 22 so as to be rotatable around pins 25 and 26 which are perpendicular to each other. Hook device 20 may be configured, for example, by attaching hook side stopper 23d to an existing hook device.

[0028] As shown in Figures 2 and 3, the first link 30 includes a plate-shaped base plate 31, a pair of first connecting portions 32a, 32b, a pair of second connecting portions 33a, 33b, a pair of guard plates 34a, 34b (plate-shaped members), mounts 35, 36, a hook catch 37 (locking portion), and a link side stopper 38.

[0029] The pair of first connecting parts 32a, 32b are arranged at one end of the base plate 31 in the longitudinal direction, spaced apart in the left-right direction. The first connecting parts 32a, 32b support a pin 42 extending in the left-right direction. The quick coupler 13 is arranged outside the pair of first connecting parts 32a, 32b, the cylindrical part 23a is arranged between the pair of first connecting parts 32a, 32b, and the pin 42 is inserted through the quick coupler 13, the pair of first connecting parts 32a, 32b, and the cylindrical part 23a. As a result, the quick coupler 13 is rotatably connected to the first connecting parts 32a, 32b via the pin 42. The hook device 20 is rotatably connected to the first connecting parts 32a, 32b via the pin 42.

[0030] The pair of second connecting parts 33a, 33b are arranged at the other end of the base plate 31 in the longitudinal direction, separated in the left-right direction. The second connecting parts 33a, 33b support a pin 43 extending in the left-right direction. One end of the pair of second links 40 is arranged outside the pair of second connecting parts 33a, 33b, the other end of the attachment cylinder 17 is arranged between the pair of second connecting parts 33a, 33b, and the pin 43 is inserted through the pair of second links 40, the pair of second connecting parts 33a, 33b, and the other end of the attachment cylinder 17. As a result, the attachment cylinder 17 is rotatably connected to the second connecting parts 33a, 33b via the pin 43. The pair of second links 40 are rotatably connected to the second connecting parts 33a, 33b via the pin 43.

[0031] The guard plate 34a is provided between the first connecting portion 32a and the second connecting portion 33a, and extends in a direction perpendicular to the base plate 31. The guard plate 34b is provided between the first connecting portion 32b and the second connecting portion 33b, and extends in a direction perpendicular to the base plate 31. That is, the pair of guard plates 34a, 34b are provided at positions spaced apart in the left-right direction, and each extends in a direction perpendicular to the base plate 31. As shown in FIG. 3B, the pair of guard plates 34a, 34b serve to prevent foreign objects from coming into contact with the hook device 20 in the stored posture.

[0032] The first connecting parts 32a, 32b and the second connecting parts 33a, 33b are provided, for example, at the four corners of the rectangular base plate 31. The first connecting parts 32a, 32b and the second connecting parts 33a, 33b have a cylindrical outer shape with a through hole extending in the left-right direction. The guard plates 34a, 34b are disposed along the long sides of the base plate 31 at both ends of the base plate 31 in the short direction.

[0033] The mounts 35, 36 are attached to the surface of the base plate 31 at a predetermined interval. The mounts 35, 36 support the hook device 20 in the storage position. The hook catch 37 is attached to the surface of the base plate 31 on the pin 43 side (in other words, the side farther from the pin 42) of the mounts 35, 36. The hook catch 37 locks the hook device 20 in the storage position and prevents the hook device 20 from changing its position to the working position. The hook catch 37 can also be operated by an operator to release the lock of the hook device 20.

[0034] The link side stopper 38 is provided across the first connecting parts 32a, 32b. The link side stopper 38 protrudes radially outward from the outer circumferential surfaces of the first connecting parts 32a, 32b. As shown in FIG. 3A, the link side stopper 38 abuts against the hook side stopper 23d when the hook device 20 rotates around the pin 42 to a predetermined position. This limits the range of rotation of the hook device 20. The surfaces (abutment surfaces) of the hook side stopper 23d and the link side stopper 38 facing each other are parts (flat surfaces) of a plane passing through the pin 42, the cylindrical part 23a, and the centers of the first connecting parts 32a, 32b. It is preferable that the hook side stopper 23d and the link side stopper 38 be in surface contact with each other.

[0035] The hook device 20 rotates around a pin 42 between a working posture shown in Fig. 3(A) and a stored posture shown in Fig. 3(B). More specifically, the hook device 20 changes its posture from the working posture to the stored posture by rotating clockwise (first direction) in Fig. 3. The hook device 20 also changes its posture from the stored posture to the working posture by rotating counterclockwise (second direction) in Fig. 3. The first direction and the second direction are opposite directions. The working posture is the posture of the hook device 20 when performing a lifting operation. The stored posture is the posture of the hook device 20 when not performing a lifting operation (for example, when the hydraulic excavator 1 is traveling or when an excavation operation is being performed by the bucket 14).

[0036] Here, if the hook device 20 rotates counterclockwise without limit, there is a possibility that the hook device 20 may come into contact (interfere with) the quick coupler 13 depending on the postures of the boom 11, the arm 12, and the bucket 14. Therefore, before the hook device 20 rotating counterclockwise interferes with the quick coupler 13, the hook side stopper 23d and the link side stopper 38 are brought into contact with each other. That is, the position of the hook side stopper 23d in the circumferential direction of the cylindrical portion 23a and the position of the link side stopper 38 in the circumferential direction of the first connecting portions 32a, 32b are appropriately adjusted depending on the shapes of the quick coupler 13, the hook device 20, and the first link 30, etc.

[0037] Also, since the hook side stopper 23d and the link side stopper 38 are manufactured, for example, by casting or cutting a metal material (for example, SUS), they may include manufacturing errors. Furthermore, since the hook side stopper 23d and the link side stopper 38 are fixed, for example, by welding to the outer circumferential surfaces of the cylindrical portion 23a and the first connecting portions 32a and 32b, they may include installation errors. Furthermore, repeated contact between the hook side stopper 23d and the link side stopper 38 may cause deterioration over time (for example, wear).

[0038] Therefore, there is a possibility that the hook device 20 will come into contact with the quick coupler 13 before the hook side stopper 23d and the link side stopper 38 come into contact with each other. Furthermore, the line or point contact between the hook side stopper 23d and the link side stopper 38 accelerates wear of the hook side stopper 23d and the link side stopper 38. Furthermore, if the hook side stopper 23d and the link side stopper 38 come into line or point contact with each other while a heavy load is suspended, the components of the front working implement 10 (particularly the quick coupler 13, the hook device 20, the first link 30, and the pins 41 and 42) may be damaged. Therefore, the hydraulic excavator 1 according to this embodiment further includes an adjustment member 50 shown in FIG. 4 in order to absorb the above-mentioned manufacturing errors, installation errors, and deterioration over time.

[0039] [Configuration of adjustment member 50] FIG. 4 is a schematic diagram of the adjustment member 50. More specifically, FIG. 4(A) is an exploded view of the adjustment member 50. FIG. 4(B) is an assembly view of the adjustment member 50 omitting the adjustment plates 52 and 53. FIG. 4(C) is an assembly view of the adjustment member 50 omitting the adjustment plate 53. The adjustment member 50 serves to adjust the contact position of the hook side stopper 23d and the link side stopper 38. As shown in FIG. 4, the adjustment member 50 includes an adjustment block 51, one or more adjustment plates 52 and 53, and a bolt 54.

[0040] The adjustment member 50 is configured to be detachably attached to a surface of the hook side stopper 23d facing the link side stopper 38. Furthermore, a bolt hole 23e into which a bolt 54 is screwed is formed in a surface of the hook side stopper 23d facing the link side stopper 38 (i.e., the surface to which the adjustment member 50 is attached). However, the adjustment member 50 may be configured to be detachably attached to a surface of the link side stopper 38 facing the hook side stopper 23d. Alternatively, the adjustment member 50 may be provided on both the hook side stopper 23d and the link side stopper 38.

[0041] The adjustment block 51 is formed, for example, by injection molding an engineering plastic (for example, MC nylon). The inner peripheral surface 51a of the adjustment block 51 may be an arcuate surface that follows the outer peripheral surface of the cylindrical portion 23a, or may be a flat surface. A surface 51b of the adjustment block 51 that faces the hook side stopper 23d is a flat surface. Similarly, a surface 51c of the adjustment block 51 that faces the link side stopper 38 is a flat surface. On the other hand, the outer peripheral surface 51d of the adjustment block 51 may have any shape (for example, an arcuate surface, a flat surface).

[0042] The faces 51b and 51c of the adjustment block 51 face each other in the circumferential direction of the cylindrical portion 23a (in other words, face opposite directions). The faces 51b and 51c of the adjustment block 51 are parallel to each other. In other words, the distance between the faces 51b and 51c of the adjustment block 51 (hereinafter, referred to as the "thickness dimension") is the same in the radial direction of the cylindrical portion 23a, the first connecting portions 32a and 32b, and the pin 42. Furthermore, the adjustment block 51 is formed with a through hole 51e that penetrates in the thickness direction (i.e., the opposing direction of the faces 51b and 51c).

[0043] The adjustment plates 52 and 53 are formed of, for example, the same material as the hook side stopper 23d. The adjustment plates 52 and 53 are flat plates sandwiched between the hook side stopper 23d and the adjustment block 51. The adjustment plates 52 and 53 are formed with through holes 52e and 53e that penetrate in the thickness direction. The through holes 52e and 53e communicate with the through hole 51e and the bolt hole 23e when the adjustment plates 52 and 53 are sandwiched between the hook side stopper 23d and the adjustment block 51. The thickness dimensions of the adjustment plates 52 and 53 may be the same or different. The number of adjustment plates 52 and 53 included in the adjustment member 50 is not limited to two. Furthermore, the adjustment plates 52 and 53 can be omitted.

[0044] 4(B), the surface 51b of the adjustment block 51 may be directly abutted against the hook-side stopper 23d. Then, the adjustment block 51 is detachably attached to the hook-side stopper 23d by screwing a bolt 54 into the communicating through-hole 51e and the bolt hole 23e.

[0045] As another example, as shown in Fig. 4(C), an adjustment plate 52 may be interposed between the surface 51b of the adjustment block 51 and the hook side stopper 23d. Then, by screwing a bolt 54 into the communicating through holes 51e, 52e and the bolt hole 23e, the adjustment block 51 and the adjustment plate 52 are detachably attached to the hook side stopper 23d. Note that the number and type (thickness) of the adjustment plates 52 sandwiched between the adjustment block 51 and the hook side stopper 23d are not limited to the example shown in Fig. 4(C).

[0046] According to the above embodiment, for example, the following advantageous effects are achieved.

[0047] According to the above embodiment, by combining the adjustment block 51 and the adjustment plates 52, 53, it is possible to absorb manufacturing errors, installation errors, and aging deterioration of the hook side stopper 23d and the link side stopper 38. This makes it possible to appropriately limit the rotation range of the hook device 20. As a result, it is possible to appropriately prevent interference between the hook device 20 and the quick coupler 13.

[0048] Furthermore, according to the above embodiment, by making the adjustment member 50 detachable from the hook side stopper 23d, it is possible to easily replace the adjustment block 51 that has deteriorated over time. This makes it possible to extend the life of the hook device 20. Furthermore, by forming the adjustment block 51 from a material that is less wear resistant than the link side stopper 38, the adjustment block 51 wears preferentially, so that only the adjustment block 51 needs to be replaced.

[0049] Furthermore, according to the above embodiment, the necessary adjustment plate 52 can be selected from a plurality of adjustment plates 52, 53 having different thicknesses, thereby improving the freedom of the timing of contact between the hook side stopper 23d and the link side stopper 38.

[0050] [Variations] FIG. 5 is a diagram showing a modified example of the adjustment member 50A. More specifically, FIG. 4(A) is an exploded view of the adjustment member 50A. FIG. 5(B) is an assembly view of the adjustment member 50A omitting the adjustment plate 53. Note that detailed description of commonalities with the above embodiment will be omitted, and differences will be mainly described. The adjustment member 50A according to the modified example differs from the above embodiment in that it includes an adjustment block 55 instead of the adjustment block 51.

[0051] The distance between faces 55b, 55c of adjustment block 55 (i.e., thickness dimension) gradually increases toward the outside in the radial direction of cylindrical portion 23a, first connecting portions 32a, 32b, and pin 42. More preferably, when faces 55b, 55c of adjustment block 55 are extended toward the inside, they intersect at the centers of cylindrical portion 23a, first connecting portions 32a, 32b, and pin 42. In other words, it is desirable that adjustment block 55 forms part of a sector when viewed from the side from the extension direction of pin 42. The other configuration of adjustment member 50A is common to adjustment member 50.

[0052] According to this modification, it becomes easier to bring the link side stopper 38 into surface contact with the adjustment block 55. This makes it possible to suppress wear on the adjustment block 55 and to suppress damage to the components of the front working implement 10 (in particular, the quick coupler 13, the hook device 20, the first link 30, and the pins 41 and 42).

[0053] The above-described embodiments are illustrative examples of the present invention, and are not intended to limit the scope of the present invention to these embodiments. Those skilled in the art can implement the present invention in various other forms without departing from the gist of the present invention. [Explanation of symbols]

[0054] 1: Hydraulic excavator 2: Lower running body 3: Upper rotating body 5: Swivel frame 6: Counterweight 7: Cab 10: Front work machine 11: Boom 12: Arm 13: Quick coupler 14: Bucket 14a, 14b, 25, 26, 41-44: Pin 15: Boom cylinder 16: Arm cylinder 17: Attachment cylinder 20: Hook device 21: Hook body 22: Bracket 23: First bracket 23a: Cylindrical section 23b, 23c: First support part 23d: Hook side stopper 23e: Bolt hole 24: Second bracket 24a: Pin insertion hole 24b, 24c: 2nd support part 30: First link 31: Base plate 32a, 32b: 1st connection part 33a, 33b: 2nd connection part 34a, 34b: Guard plate 35,36: Mount 37: Hook catch 38: Link side stopper 40: Second link 50, 50A: Adjustment parts 51,55: Adjustment block 51a: Inner surface 51a-51d,55a-55d: Surface 51d: Outer surface 51e, 52e, 53e: Through hole 52,53: Adjustment plate 54: Bolt

Claims

1. The car body and A boom connected to the vehicle body so as to be capable of being raised and lowered; An arm rotatably connected to the tip of the boom; A quick coupler rotatably connected to the tip of the arm; an attachment detachably engaged with the quick coupler; an attachment cylinder that rotates the quick coupler relative to the arm; a hook device for suspending a load from a tip end of the arm; A working machine including a connecting link that rotatably connects the quick coupler, the attachment cylinder, and the hook device, The hook device includes a hook side stopper for limiting a rotation range, The connecting link is A first connecting portion rotatably connected to the quick coupler and the hook device; A second connecting portion rotatably connected to a tip end of the attachment cylinder; a link side stopper provided on an outer circumferential surface of the first connecting portion and abutting against the hook side stopper when the hook device is rotated to a predetermined position; The working machine further comprises an adjustment member that adjusts a contact position between the hook side stopper and the link side stopper in a circumferential direction of the first connecting portion.

2. 2. The work machine according to claim 1, a working machine characterized in that the adjustment member includes an adjustment block that is detachably attached to one of the hook side stopper and the link side stopper and abuts the other of the hook side stopper and the link side stopper.

3. 3. The work machine according to claim 2, A work machine, wherein a thickness dimension of the adjustment block is constant in a radial direction of the first connecting portion.

4. 3. The work machine according to claim 2, A working machine, wherein a thickness dimension of the adjustment block gradually increases toward the radially outer side of the first connecting portion.

5. 3. The work machine according to claim 2, A working machine characterized in that the adjustment member includes an adjustment plate that is sandwiched between the hook side stopper or the link side stopper and the adjustment block.

Images