Construction machine
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-12-05
- Publication Date
- 2026-08-13
Smart Images
Figure JP2025042508_13082026_PF_FP_ABST
Abstract
Description
Construction machinery
[0001] The present disclosure relates to construction machinery such as a hydraulic excavator equipped with a working device used for, for example, earth and sand excavation work, building demolition work, and the like.
[0002] Generally, a hydraulic excavator, which is a representative example of construction machinery, is composed of a self - propelled lower traveling body, an upper revolving body rotatably mounted on the lower traveling body, and a working device rotatably provided on the front side of the upper revolving body.
[0003] The working device includes a boom rotatably provided on the front side of the upper revolving body, an arm rotatably provided at the tip of the boom, a bucket rotatably provided at the tip of the arm, a boom cylinder for rotating the boom, an arm cylinder for rotating the arm, and a bucket cylinder for rotating the bucket.
[0004] Then, the hydraulic excavator can perform earth and sand excavation work and the like by rotating the upper revolving body on the lower traveling body and expanding and contracting the boom cylinder, arm cylinder, and bucket cylinder to rotate the boom, arm, and bucket.
[0005] Further, some working devices are configured to be able to perform operations such as gripping and moving objects (such as wood and rubble) that cannot fit into the bucket. This working device includes a gripper rotatably provided at the tip of the arm for gripping an object between the gripper and the bucket, a gripper cylinder in which a tube serving as a fixed end is provided on the arm and a rod serving as a movable end moves by expansion and contraction to rotate the gripper, a first link having one end rotatably provided on the rod of the gripper cylinder and the other end rotatably provided on the gripper, and a second link having one end rotatably provided on the arm and the other end rotatably provided at the connection portion between the tip of the rod and the first link (Patent Document 1).
[0006] U.S. Patent Application Publication No. 2004 / 0261301
[0007] Incidentally, Patent Document 1 describes a gripping cylinder in which the tip of the rod is connected to a second link that is rotatably mounted on the arm. In this structure, when the second link rotates and rises relative to the longitudinal direction of the arm, the gripping cylinder is positioned away from the arm. When the arm, boom, or upper slewing body is moved (the object is moved) while the gripping cylinder is away from the arm in this state (for example, when an object is gripped by the bucket and gripping device), there is a risk that the gripping cylinder will come into contact with surrounding obstacles. As a result, the operator has to take extra care to prevent the gripping cylinder from coming into contact with obstacles, which can lead to decreased work efficiency or necessitate the need for a cover or other protective device for the gripping cylinder.
[0008] The object of the present invention is to provide a construction machine that can improve work efficiency by suppressing contact of the gripping cylinder with obstacles and the like.
[0009] The present invention relates to a construction machine having a vehicle body and a work device provided on the vehicle body, wherein the work device comprises a boom rotatably mounted on the vehicle body, an arm rotatably mounted at the tip of the boom, a bucket rotatably mounted at the tip of the arm, a gripping device rotatably mounted at the tip of the arm for gripping an object between itself and the bucket, and a gripping device cylinder whose fixed end is provided on the arm and whose movable end moves by extension or retraction, thereby rotating the gripping device via a link, wherein the arm is provided with a guide member that guides the movable end of the gripping device cylinder to follow the arm when the movable end moves and rotates the gripping device via the link.
[0010] According to the present invention, contact of the gripping device cylinder with obstacles and the like can be suppressed, thereby improving work efficiency.
[0011] This is a left side view of a hydraulic excavator according to an embodiment of the present invention. This is a perspective view showing the arm, bucket, gripping device, bucket cylinder, gripping device cylinder, link, guide member, etc. in Figure 1 with the gripping device cylinder fully extended. This is a rear view showing the arm, bucket, gripping device, gripping device cylinder, link, guide member, etc. with the gripping device cylinder fully extended. This is a left side view showing the arm, bucket, gripping device, bucket cylinder, gripping device cylinder, link, guide member, etc. with the gripping device cylinder fully extended. This is a perspective view showing the arm, bucket, gripping device, bucket cylinder, gripping device cylinder, link, guide member, etc. with the gripping device cylinder fully retracted. This is a left side view showing the arm, bucket, gripping device, bucket cylinder, gripping device cylinder, link, guide member, etc. with the gripping device cylinder fully retracted. This is a perspective view showing the arm, bucket, gripping device, bucket cylinder, gripping device cylinder, link, guide member, etc. with the gripping device cylinder extended to an intermediate position. This is a left side view showing the arm, bucket, gripping device, bucket cylinder, gripping device cylinder, link, guide member, etc., with the gripping device cylinder extended to an intermediate position. This is a perspective view showing the gripping device cylinder, link, and guide member disassembled from the arm and bucket. This is a perspective view showing the link. This is a perspective view showing the guide portion of the guide member. This is a perspective view showing the movable part in its assembled state. This is a perspective view showing the movable part in its disassembled state. This is a perspective view showing the pin member in Figure 13. This is a perspective view showing the sliding part in Figure 13 from the front side. This is a perspective view showing the sliding part from the back side. This is a perspective view showing the spacer in Figure 13.
[0012] Hereinafter, embodiments of the construction machinery according to the present invention will be described using a hydraulic excavator, a representative example of construction machinery, with reference to Figures 1 to 17. In this embodiment, regardless of the rotational position of the upper slewing body, the side where the working device is located will be described as the front, the side where the counterweight is located as the rear, the side where the cab is located as the left side, and the side opposite the cab as the right side. Furthermore, the rotational directions of the boom, arm, bucket, gripping device, etc., which constitute the working device will be described as the vertical and longitudinal directions relative to the upper slewing body as the vehicle body. In addition, the width direction of the arm, etc., will be described as the left-right direction.
[0013] In Figure 1, the hydraulic excavator 1 is composed of a self-propelled crawler-type lower vehicle 2 and an upper rotating vehicle 3 that is rotatably mounted on the lower vehicle 2. A work device 11, described later, is rotatably mounted on the front of the upper rotating vehicle 3. The hydraulic excavator 1 can travel using the lower vehicle 2 and perform tasks such as excavating soil and demolishing buildings using the work device 11. The lower vehicle 2 and the upper rotating vehicle 3 constitute the vehicle body of the present invention.
[0014] The upper rotating body 3 is composed of a rotating frame 4 that forms a support structure, a cab 5 provided on the left front side of the rotating frame 4, a counterweight 6 provided on the rear of the rotating frame 4 to balance the weight with the working device 11, and an exterior cover 7 provided on the rotating frame 4 that covers the engine, hydraulic pump, control valve device, etc. (none of which are shown).
[0015] Next, the working device 11, which is rotatably mounted on the upper rotating body 3 that constitutes the body of the hydraulic excavator 1, will be described in detail.
[0016] The working device 11 is located on the front side of the slewing frame 4. The working device 11 consists of a boom 12, an arm 13, a bucket 14, a boom cylinder 16, an arm cylinder 17, a bucket cylinder 18, a gripping device 20, and a guide member 28. The working device 11 is used for tasks such as excavating soil and demolishing buildings.
[0017] The boom 12 is mounted on the front side of the upper slewing body 3 so as to be rotatable in the vertical or longitudinal direction. The boom 12 is made of an L-shaped bent rectangular tube and is rotatably mounted on the slewing frame 4 with its longitudinal base end as a pivot point. The boom connecting boss portion 13D of the arm 13, which will be described later, is rotatably connected to the tip of the boom 12.
[0018] The arm 13 is mounted on the tip of the boom 12 so as to be rotatable in the vertical or horizontal direction, with its longitudinal base end as a pivot point. As shown in Figure 2, the arm 13 is formed as a rectangular tube that tapers from the base end to the tip. Specifically, when the arm 13 extends forward, it comprises an upper plate 13A and a lower plate 13B facing each other with a gap between them in the vertical direction, and left and right side plates 13C facing each other so as to sandwich the upper plate 13A and the lower plate 13B in the left-right direction, which is the width direction.
[0019] A boom connecting boss portion 13D is provided at the base end of the arm 13. This boom connecting boss portion 13D is rotatably connected to the tip of the boom 12. On the other hand, a bucket connecting boss portion 13E, which is a cylindrical body extending in the left-right direction, is provided at the tip of the arm 13.
[0020] Furthermore, the arm 13 is provided with a bucket cylinder bracket 13F on the base end side of the upper plate 13A. In addition, a gripping cylinder bracket 13G is provided on the middle of the longitudinal portion of the lower plate 13B, located closer to the base end.
[0021] The bottom end of the bucket cylinder 18 tube is attached to the bucket cylinder bracket 13F. The first boss portion 26C of the tube 26A, which is the fixed end of the gripping cylinder 26, is attached to the gripping cylinder bracket 13G.
[0022] Furthermore, the lower plate 13B of the arm 13 is provided on the lower side opposite to the bucket cylinder 18. A guide portion 29 of the guide member 28, which will be described later, is provided on this lower plate 13B, located near the tip of the arm 13.
[0023] The bucket 14 is mounted on the tip of the arm 13 so as to be rotatable in the vertical or horizontal direction. The bucket 14 comprises a container-shaped bucket body 14A for scooping up and storing soil and other materials through its opening, a pair of mounting plates 14B erected at a distance from each other in the left-right direction at the base end of the bucket body 14A, and a tip edge 14C extending in the left-right direction at the tip of the bucket body 14A. Excavation claws and the like (not shown) can also be attached to this tip edge 14C.
[0024] The pair of mounting plates 14B extend from the bottom side of the bucket body 14A toward the opening side. The opening sides of the pair of mounting plates 14B are positioned on either side of the bucket connecting boss portion 13E of the arm 13 and are rotatably connected using the bucket pin 15 described later. In addition, the bucket link 19 described later is rotatably attached to the bottom side of the pair of mounting plates 14B.
[0025] The bucket pin 15 supports the bucket 14 at the tip of the arm 13 so that it can rotate vertically or in the front-to-back direction. The bucket pin 15 is inserted into the bucket connecting boss portion 13E, and the protruding portion that extends from the bucket connecting boss portion 13E is connected to a pair of mounting plates 14B of the bucket 14. Furthermore, both ends of the bucket pin 15 extend beyond the pair of mounting plates 14B. Both ends of the extended bucket pin 15 are inserted into the mounting bosses 22A of the mounting portion 22 that constitutes the gripping device 20, which will be described later.
[0026] Two boom cylinders 16 are provided, positioned to sandwich the boom 12 from side to side (only one is shown in Figure 1). These two boom cylinders 16 are located between the slewing frame 4 and the boom 12, causing the boom 12 to rotate vertically or longitudinally. The bottom end of the tube of the boom cylinder 16 is attached to the slewing frame 4. The protruding end of the rod of the boom cylinder 16 is attached to the middle of the longitudinal side of the boom 12.
[0027] The arm cylinder 17 is installed between the boom 12 and the arm 13, and rotates the arm 13 in the vertical or longitudinal direction. The bottom end of the tube of the arm cylinder 17 is attached to the upper surface of the boom 12. The protruding end of the rod of the arm cylinder 17 is attached to the base end of the arm 13.
[0028] The bucket cylinder 18 is mounted on the upper plate 13A of the arm 13. The bottom end of the bucket cylinder 18's tube is attached to the bucket cylinder bracket 13F of the arm 13. The protruding end of the rod of the bucket cylinder 18 is attached to the bucket 14 via the bucket link 19. The bucket cylinder 18 rotates the bucket 14 in the vertical or horizontal direction via the bucket link 19.
[0029] The bucket link 19 is provided to connect the arm 13, the bucket 14, and the bucket cylinder 18. The bucket link 19 converts the extension and retraction motion of the bucket cylinder 18 into a large rotational motion of the bucket 14.
[0030] The gripping device 20 has its longitudinal base end mounted on the tip of the arm 13 so as to be rotatable in the vertical or horizontal direction. The gripping device 20 is also mounted so as to be rotatable with the same axis as the bucket 14 as its pivot point. As a result, the gripping device 20 can grip an object between itself and the bucket 14 at its tip.
[0031] The gripping device 20 rotates around the bucket pin 15 between the arm 13 and the bucket 14, that is, between a position close to the lower plate 13B side of the arm 13 (the position shown in Figures 5 and 6) and a position on the extension line of the lower plate 13B of the arm 13 (the position shown in Figures 2 and 4). As shown in Figures 2 to 9, the gripping device 20 is composed of a main body portion 21, a mounting portion 22, a claw portion 23, and a link bracket 24, which will be described later.
[0032] The main body 21 comprises a rectangular base plate 21A that faces the opening side of the bucket 14, left and right side plates 21B erected from the left and right sides of the base plate 21A on the side opposite to the bucket 14, and a reinforcing plate 21C that extends in the left-right direction and is erected on the end edge of the base plate 21A on the tip side of the gripping device 20, with its left and right ends attached to the side plates 21B.
[0033] The left and right mounting portions 22 extend from the left and right side plates 21B toward the base end of the gripping device 20. The left and right mounting portions 22 curve to avoid the edge on the opening side of the bucket 14. At the base ends of the left and right mounting portions 22, cylindrical mounting bosses 22A are provided, with an axis extending in the left-right direction as the center line. The left and right mounting bosses 22A are positioned to sandwich the left and right mounting plates 14B of the bucket 14. Both ends of the bucket pin 15 are rotatably inserted into the mounting bosses 22A.
[0034] The claw portions 23 are provided extending from the center of the left and right side plates 21B and the reinforcing plate 21C toward the tip of the gripping device 20. The three claw portions 23 are curved toward the bucket 14 and have a tapered shape. The three claw portions 23 have a length dimension that allows them to approach or contact the tip edge 14C of the bucket 14. The claw portions 23 can grip an object between themselves and the tip edge 14C of the bucket 14. Two or more claw portions 23 may also be provided.
[0035] The link bracket 24 is provided on the side of the base plate 21A opposite to the bucket 14. The link bracket 24 is formed by two facing plates spaced apart in the left-right direction. Pin holes 24A (see Figure 9) are provided through the two link brackets 24 in the left-right direction. With the second link boss 27C of the link 27 (described later) positioned between the link brackets 24, mounting pins 25 are inserted into the pin holes 24A and the second link boss 27C. As a result, the second link boss 27C is rotatably attached to the link bracket 24.
[0036] The gripping cylinder 26 is located on the lower side of the arm 13, that is, on the lower plate 13B side, opposite to the bucket cylinder 18. The gripping cylinder 26 has a fixed end tube 26A whose bottom side is attached to the arm 13, and the rod 26B, which is the movable end, moves as it expands and contracts, thereby rotating the gripping device 20 via the link 27. A piston (not shown) is inserted inside the tube 26A with the rod 26B connected to it. The gripping cylinder 26 has a first boss portion 26C on the bottom side of the tube 26A and a second boss portion 26D on the tip side of the rod 26B.
[0037] The gripping cylinder 26 has a first boss portion 26C on the tube 26A side that is rotatably attached to the gripping cylinder bracket 13G of the arm 13 using a mounting pin 25. The second boss portion 26D on the rod 26B side is movably engaged with the elongated hole 29A of the guide portion 29 via a movable portion 32, which will be described later.
[0038] In this case, as will be described later, the elongated hole 29A of the guide portion 29 is positioned close to the lower plate 13B of the arm 13, so the gripping cylinder 26 is positioned close to the lower plate 13B and aligned with the lower plate 13B. This structure aligned with the lower plate 13B includes not only a configuration in which the gripping cylinder 26 extends parallel to the lower plate 13B, but also a configuration in which it is slightly inclined, as long as it does not deviate significantly from the lower plate 13B.
[0039] Furthermore, as shown in Figures 4, 6, and 8, the gripping cylinder 26 is positioned closer to the lower plate 13B than the protruding end 13G1 of the gripping cylinder bracket 13G. As a result, the entire gripping cylinder 26 remains firmly attached to the lower plate 13B regardless of its position when the rod 26B extends or retracts. Therefore, the gripping cylinder 26 does not move significantly away from (protrude from) the lower plate 13B.
[0040] Link 27 is provided between the gripping cylinder 26 and the gripping device 20. As shown in Figure 10, link 27 is composed of a Y-shaped link body 27A, which is bifurcated at the base end in the longitudinal direction and narrower at the tip end; a first link boss 27B located at the base end of link body 27A and sandwiching the second boss portion 26D of the gripping cylinder 26; and a second link boss 27C located at the tip of link body 27A.
[0041] Link 27 has a first link boss 27B, which is the base end, rotatably mounted on a rod 26B, which is the movable end of the gripping cylinder 26. On the other hand, link 27 has a second link boss 27C, which is the tip end, rotatably mounted on the gripping device 20.
[0042] Specifically, the first link boss 27B of the link 27 inserts the pin member 33 of the moving part 32 described later inside while sandwiching the second boss part 26D of the gripper cylinder 26 between the guide parts 29 described later. As a result, the first link boss 27B of the link 27 moves in the longitudinal direction of the arm 13 along the long hole 29A of the guide part 29 together with the second boss part 26D of the gripper cylinder 26. At this time, the link 27 switches the expansion and contraction operation of the rod 26B of the gripper cylinder 26 along the arm 13 to the rotation operation of the gripper 20.
[0043] Next, the configuration and guide function of the guide member 28, which is a characteristic part of this embodiment, will be described in detail.
[0044] The guide member 28 is provided on the arm 13. The guide member 28 guides the rod 26B along the arm 13 when the rod 26B, which is the movable end of the gripper cylinder 26, moves and rotates the gripper 20 via the link 27. Further, the guide member 28 restricts the range in which the rod 26B of the gripper cylinder 26 moves to be smaller than the maximum extension and the minimum contraction of the gripper cylinder 26. That is, the guide member 28 restricts the extension operation of the rod 26B before the maximum extension and restricts the contraction operation of the rod 26B before the minimum contraction. The guide member 28 includes a guide part 29, an extension side stopper part 30, a contraction side stopper part 31, and a moving part 32, which will be described later.
[0045] The guide part 29 is provided on the lower plate 13B of the arm 13. The guide part 29 is located near the bucket connection boss part 13E on the tip side of the lower plate 13B and is formed as a pair of vertical plates arranged at intervals in the left - right direction, which is the width direction of the arm 13. The pair of guide parts 29 has a rectangular shape that is long in the longitudinal direction of the arm 13, and the height dimension from the lower plate 13B is kept low. The height dimension of the guide part 29 is set to, for example, the dimension obtained by combining the diameter dimension of the second boss part 26D of the gripper cylinder 26 and the gap for preventing clogging of earth and sand between the lower plate 13B and the second boss part 26D.
[0046] The pair of guide portions 29 are provided with elongated holes 29A extending in the moving direction of the rod 26B of the gripper cylinder 26. In this elongated hole 29A, a moving portion 32 (described later) that connects the rod 26B (second boss portion 26D) of the gripper cylinder 26 and the first link boss 27B of the link 27 is engaged so as to be movable along the lower plate 13B at a position close to the lower plate 13B of the arm 13. In this case, since the elongated hole 29A guides the moving portion 32 so that it does not move far away from the lower plate 13B, the elongated hole 29A can be provided in a state inclined (a state other than parallel) with respect to the lower plate 13B.
[0047] As shown in FIG. 11, in the elongated hole 29A, the inner edge portions facing each other in the short side direction serve as sliding contact edges 29A1. The sliding contact surface 34B of the sliding portion 34 constituting the moving portion 32 is movably in contact with the sliding contact edge 29A1. The sliding contact edge 29A1 (guide portion 29) has higher wear resistance than the sliding contact surface 34B of the sliding portion 34.
[0048] The extension side stopper portion 30 is provided on the guide portion 29 at the end portion on the gripper 20 side of the elongated hole 29A. The extension side stopper portion 30 restricts the extension operation of the gripper cylinder 26 before the gripper cylinder 26 reaches its maximum extension. Specifically, the extension side stopper portion 30 has a structure in which it abuts against the pin member 33 of the moving portion 32 at a stage before the rod 26B of the gripper cylinder 26 reaches its maximum extension. Thereby, when the gripper 20 is further pressed toward the bucket 14 side from the states shown in FIGS. 2 and 4, the extension side stopper portion 30 can prevent the rod 26B of the gripper cylinder 26 from being pulled out beyond the extension limit and damaged by abutting the pin member 33 of the moving portion 32.
[0049] The retraction-side stopper portion 31 is located on the guide portion 29 at the end of the elongated hole 29A opposite to the gripping tool 20. The retraction-side stopper portion 31 restricts the retraction movement of the gripping tool cylinder 26 before it is fully retracted. Specifically, the retraction-side stopper portion 31 is structured to contact the pin member 33 of the movable portion 32 before the rod 26B of the gripping tool cylinder 26 is fully retracted. As a result, when the gripping tool 20 is pushed further toward the arm 13 from the state shown in Figures 5 and 6, the retraction-side stopper portion 31 contacts the pin member 33 of the movable portion 32, thereby preventing the rod 26B of the gripping tool cylinder 26 from being pushed beyond its retraction limit and being damaged.
[0050] The movable part 32 connects the rod 26B (second boss portion 26D) of the gripping cylinder 26 to the first link boss 27B of the link 27. The movable part 32 is also movably engaged with the elongated hole 29A of the guide portion 29. This allows the movable part 32 to move the rod 26B of the gripping cylinder 26 and the first link boss 27B of the link 27 along the elongated hole 29A of the guide portion 29. As shown in Figures 12 and 13, the movable part 32 is composed of a pin member 33, a sliding portion 34, a bolt 35, a nut 36, and a spacer 37, which will be described later.
[0051] As shown in Figure 14, the pin member 33 is formed as a cylindrical body extending in the left-right direction. The pin member 33 has a length dimension that exceeds the left and right guide portions 29, and a diameter dimension that is smaller than the dimension (inner width dimension) between the sliding contact edges 29A1 facing each other in the short direction of the elongated hole 29A.
[0052] Furthermore, sliding part mounting surfaces 33A are formed at both axial ends of the pin member 33 so as to face each other across the axis. The pair of sliding part mounting surfaces 33A facing each other in the radial direction are formed as rectangular chamfered portions that are parallel to each other and are at the same distance from the axis of the pin member 33.
[0053] The pin member 33 is provided with, for example, two bolt insertion holes 33B that penetrate across a pair of sliding part mounting surfaces 33A. The bolt insertion holes 33B are formed near the tip of the pin member 33 such that, with the movable part 32 mounted across the left and right guide parts 29, the bolts 35 and nuts 36, described later, that are inserted into the bolt insertion holes 33B are positioned further outward in the left-right direction than the guide parts 29.
[0054] As shown in Figure 9, the pin member 33 is rotatably inserted between the first link boss 27B of the link 27 and the rod 26B of the gripping cylinder 26. In this state, by attaching sliding parts 34 etc. to the four sliding part mounting surfaces 33A, the first link boss 27B of the link 27 and the rod 26B of the gripping cylinder 26 are held in place by the pin member 33 in a manner that prevents them from coming loose.
[0055] The sliding portion 34 is provided at both axial ends of the pin member 33. The sliding portion 34 is formed as a thick, roughly rectangular plate. The sliding portion 34 is positioned to slide against the sliding contact edge 29A1 of the elongated hole 29A of the guide portion 29. Furthermore, the sliding portion 34 is formed to wear out before the sliding contact edge 29A1 (guide portion 29) when it comes into sliding contact (frictional contact) with the sliding contact edge 29A1 of the elongated hole 29A. In addition, the sliding portion 34 can be easily attached to and detached from the pin member 33.
[0056] More specifically, as shown in Figures 15 and 16, the sliding portion 34 comprises a mounting surface 34A that faces the sliding portion mounting surface 33A of the pin member 33 with a spacer 37 in between, and a sliding contact surface 34B on the opposite side of the mounting surface 34A. The axial length dimension of the sliding portion 34 is set to be the same as that of the sliding portion mounting surface 33A of the pin member 33. Furthermore, the thickness dimension of the sliding portion 34 is set such that, when the mounting surface 34A is in contact with the sliding portion mounting surface 33A of the pin member 33 via the spacer 37, the sliding contact surface 34B protrudes beyond the outer circumferential surface of the cylindrical portion of the pin member 33.
[0057] The wear resistance of the sliding portion 34, either overall or on its sliding surface 34B, is set lower than that of the sliding edge 29A1 of the elongated hole 29A. In other words, the sliding portion 34, either overall or on its sliding surface 34B, is more prone to wear than the sliding edge 29A1 of the elongated hole 29A, and is therefore subject to replacement due to wear.
[0058] When the sliding portion 34 is attached to the pin member 33 (sliding portion mounting surface 33A), the area from the axial middle of the pin member 33 inward (the inner portion in the left-right direction) is the sliding contact area, and the area from the middle outward (the outer portion in the left-right direction) is the mounting area. In the inner sliding contact area, the sliding contact surface 34B slides against the sliding contact edge 29A1 of the elongated hole 29A. In the outer mounting area, two bolt insertion holes 34C are provided, extending through the plate thickness direction, at positions corresponding to the bolt insertion holes 33B of the pin member 33.
[0059] The sliding part 34 is then mounted to a pair of sliding part mounting surfaces 33A facing each other radially on the pin member 33, with the mounting surface 34A in contact via a spacer 37. In this state, a bolt 35 is inserted into the bolt insertion holes 34C and 33B, and a nut 36 is screwed onto the protruding end of the bolt 35. This allows the sliding part 34 to be easily attached to and detached (replaced) from the pin member 33 using the bolt 35 and nut 36.
[0060] The sliding portion 34 has a side surface 34D in the direction of movement of the movable portion 32, between the mounting surface 34A and the sliding contact surface 34B. Of the side surface 34D, the corner on the sliding contact surface 34B side that slides against the sliding contact edge 29A1 of the elongated hole 29A of the guide portion 29 is a scraped portion 34E. This scraped portion 34E has an acute angle shape because the sliding contact surface 34B protrudes by a dimension A in the direction of movement of the movable portion 32 compared to the mounting surface 34A.
[0061] Therefore, when the sliding surface 34B of the sliding part 34 slides along the sliding edge 29A1 of the elongated hole 29A, the sliding part 34 can efficiently scrape off any foreign matter adhering to the sliding edge 29A1 with the sharp scraping portion 34E. This prevents foreign matter from getting caught between the sliding edge 29A1 of the elongated hole 29A and the sliding surface 34B of the sliding part 34 when the sliding part 34 is in motion.
[0062] Furthermore, the sliding portion 34 is provided with an inclined portion 34F at the part that slides against the sliding edge 29A1 of the elongated hole 29A. This inclined portion 34F sweeps out foreign matter adhering to the sliding edge 29A1 of the elongated hole 29A. The inclined portion 34F is located at the sliding contact portion of the sliding portion 34 and is provided at the end of the moving portion 32 in the direction of movement. The inclined portion 34F is provided connected to the scraping portion 34E and is inclined from the inside to the outside of the elongated hole 29A when the sliding portion 34 is attached to the moving portion 32. In other words, the inclined portion 34F is formed as an inclined surface in which the width dimension of the sliding portion 34 gradually widens in the direction of movement from the middle part in the left-right direction toward the inside, specifically, the inside part is wider by dimension B than the middle part in the left-right direction.
[0063] Therefore, when the sliding surface 34B of the sliding hole 29A slides along the sliding edge 29A1 of the elongated hole 29A, the scraping portion 34E scrapes off foreign matter adhering to the sliding edge 29A1, and then the scraped-off foreign matter is pushed out along the inclined portion 34F by the scraped-off foreign matter, moving it to the outside and sweeping it away. This prevents foreign matter from accumulating in the elongated hole 29A.
[0064] As shown in Figures 13 and 17, the spacer 37 is provided between the mounting surface 33A of the pin member 33 and the mounting surface 34A of the sliding part 34. Multiple types of spacers 37 with different plate thicknesses, or multiple thin spacers, are provided. When installing a new sliding part 34, the spacer 37 may not be provided, and the spacer 37 may be provided according to the amount of wear on the sliding part 34.
[0065] Furthermore, when the sliding contact surface 34B of the sliding part 34 wears down, the spacer 37 can be replaced with one that is thicker by the amount of wear, or the number of spacers stacked on top can be increased by the amount of wear, thereby maintaining the mounting height position of the sliding part 34 (the sliding contact state of the sliding contact surface 34B with the sliding contact edge 29A1 of the elongated hole 29A) at an appropriate value. As a result, the sliding part 34 can be used for a long period of time, even with wear (the replacement cycle can be extended).
[0066] Furthermore, the spacer 37 is formed in an E-shape by providing two grooves 37A through which the bolt 35 passes in a rectangular plate body. As a result, the spacer 37 can be easily attached and detached by simply loosening the bolt 35 and lifting the sliding part 34 (creating a gap for insertion) without removing the sliding part 34, bolt 35, and nut 36.
[0067] As shown in Figure 9, the guide member 28 configured in this way has the first link boss 27B of the link 27 positioned between the left and right guide portions 29, and the second boss portion 26D of the gripping cylinder 26 positioned between the first link bosses 27B. In this state, the pin member 33 is inserted into the elongated hole 29A of the guide portion 29, the first link boss 27B, and the second boss portion 26D. Next, a spacer 37 and a sliding portion 34 are positioned between the sliding portion mounting surface 33A of the pin member 33 and the sliding contact edge 29A1 of the elongated hole 29A, and these are fixed to the sliding portion mounting surface 33A with bolts 35 and nuts 36. The second link boss 27C of the link 27 is rotatably attached to the link bracket 24 of the gripping device 20 using a mounting pin 25.
[0068] As a result, when the rod 26B of the gripping cylinder 26 is extended or retracted, the guide member 28 moves together with the movable part 32 so that the first link boss 27B of the link 27 is aligned with the elongated hole 29A of the guide part 29. At this time, the link 27 connected to the movable part 32 rotates the gripping device 20.
[0069] The working device 11 of the hydraulic excavator 1 according to this embodiment has the configuration described above. When performing building demolition work using this working device 11, the bucket cylinder 18 is extended or retracted to rotate the bucket 14, and the gripping cylinder 26 is extended or retracted to rotate the gripping device 20. As a result, the bucket 14 and the gripping device 20 can grip and demolish the object to be demolished, or grip the demolished material (reinforcement bars, etc.) and transport it to a desired disposal site.
[0070] In this case, as described in Patent Document 1, if the link or gripping cylinder is separated from the arm, the operator has to take extra care to prevent the link or gripping cylinder from coming into contact with an obstacle, which reduces work efficiency. Alternatively, a cover or the like is needed to protect the gripping cylinder, etc.
[0071] However, according to this embodiment, the arm 13 is provided with a guide member 28 that guides the rod 26B, which is the movable end of the gripping cylinder 26, to move along the arm 13 when the rod 26B moves and rotates the gripping device 20 via the link 27.
[0072] Therefore, since the rod 26B of the gripping cylinder 26 moves along the arm 13 by the guide member 28, the rod 26B of the gripping cylinder 26 and the first link boss 27B of the link 27 never move away from the arm 13. This suppresses contact between the gripping cylinder 26 and the link 27 and obstacles, so the operator does not need to pay extra attention. As a result, work efficiency can be improved. In addition, covers and other protective devices for the gripping cylinder 26 can be eliminated, reducing costs.
[0073] The guide member 28 includes an extension-side stopper portion 30 and a contraction-side stopper portion 31 that restrict the range of movement of the rod 26B of the gripping cylinder 26 to be smaller than the maximum extension and maximum contraction of the gripping cylinder 26.
[0074] As a result, the extension-side stopper portion 30 prevents the rod 26B of the gripping cylinder 26 from being pulled out beyond its extension limit and being damaged. In addition, the retraction-side stopper portion 31 prevents the rod 26B of the gripping cylinder 26 from being pushed in beyond its retraction limit and being damaged.
[0075] Link 27 is rotatably mounted at one end on a rod 26B which is the movable end of the gripping cylinder 26, and at the other end on the gripping device 20. The guide member 28 includes a movable part 32 that connects the rod 26B of the gripping cylinder 26 and the first link boss 27B which is one end of the link 27, a guide part 29 in which an elongated hole 29A is formed and into which the movable part 32 is movably engaged, and an extension-side stopper part 30 and a retraction-side stopper part 31 located at the end of the elongated hole 29A and provided on the guide part 29, which restrict the range of movement of the rod 26B of the gripping cylinder 26 when the movable part 32 comes into contact with them.
[0076] As a result, the guide member 28 can move its movable part 32 along the elongated hole 29A of the guide part 29, thereby keeping the rod 26B of the gripping cylinder 26 and the first link boss 27B of the link 27, which are connected by the movable part 32, always in the vicinity of the arm 13. Furthermore, the extension-side stopper part 30 and the retraction-side stopper part 31 can be easily provided using the elongated hole 29A of the guide part 29.
[0077] The arm 13 is equipped with a bucket cylinder 18 for rotating the bucket 14, and a gripping cylinder 26 and a guide member 28 are positioned on the lower plate 13B on the underside of the arm 13, opposite the bucket cylinder 18. This allows the gripping cylinder 26 and the guide member 28 to be placed on the opposite side from the bucket cylinder 18.
[0078] The guide section 29 is formed as a pair of vertical plates spaced apart in the width direction of the arm 13. This simplifies the configuration of the guide section 29.
[0079] The movable part 32 is equipped with a detachable sliding part 34, which slides against the elongated hole 29A via the sliding part 34. As a result, the movable part 32 only needs to be replaced when the sliding part 34 is worn, thus improving the workability of replacement work for worn parts.
[0080] The sliding portion 34 is provided on the surface that slides against the elongated hole 29A and includes a scraping portion 34E for scraping off foreign matter adhering to the elongated hole 29A, and an inclined portion 34F connected to the scraping portion 34E that slopes from the inside to the outside of the elongated hole 29A when the sliding portion 34 is attached to the movable portion 32.
[0081] As a result, the scraping portion 34E can scrape off foreign matter adhering to the elongated hole 29A when the sliding contact surface 34B of the sliding portion 34 slides along the elongated hole 29A. Furthermore, when the sliding contact surface 34B of the sliding portion 34 slides along the elongated hole 29A, the scraping portion 34E scrapes off foreign matter adhering to the elongated hole 29A, and then pushes the scraped-off foreign matter along the inclined portion 34F, thereby sweeping the foreign matter out to the outside.
[0082] In this embodiment, a hydraulic excavator 1 equipped with a crawler-type lower traveling body 2 was given as an example of a construction machine. However, the present invention is not limited to this and can also be applied to, for example, a wheeled excavator equipped with a wheeled lower traveling body.
[0083] 1 Hydraulic excavator (construction machine) 2 Lower traveling body (vehicle body) 3 Upper rotating body (vehicle body) 11 Working device 13 Arm 13B Lower plate (underside) 13D Boom connecting boss (base end) 13E Bucket connecting boss (tip) 14 Bucket 18 Bucket cylinder 20 Gripping device 26 Gripping device cylinder 26A Tube (fixed end) 26B Rod (movable end) 27 Link 27B First link boss (one end) 27C Second link boss (other end) 28 Guide member 29 Guide part 29A Slotted hole 29A1 Sliding contact edge 30 Extension side stopper part (stopper part) 31 Retraction side stopper part (stopper part) 32 Moving part 34 Sliding part 34E Scraping part 34F Inclined part
Claims
1. A construction machine having a vehicle body and a work device provided on the vehicle body, wherein the work device comprises: a boom rotatably mounted relative to the vehicle body; an arm rotatably mounted at the tip of the boom; a bucket rotatably mounted at the tip of the arm; a gripping device rotatably mounted at the tip of the arm for gripping an object between itself and the bucket; and a gripping device cylinder having a fixed end provided on the arm, the movable end moving as the gripping device extends and retracts to rotate the gripping device via a link, wherein the arm is provided with a guide member that guides the movable end of the gripping device cylinder to move along the arm when the movable end moves and rotates the gripping device via the link.
2. A construction machine according to claim 1, characterized in that the guide member restricts the range of movement of the movable end of the gripping cylinder to be smaller than the maximum extension and maximum contraction of the gripping cylinder.
3. A construction machine according to claim 2, wherein the link is rotatably provided at one end on the movable end of the gripping cylinder and at the other end on the gripping device, and the guide member comprises: a movable part that connects the movable end of the gripping cylinder and the one end of the link; a guide part having an elongated hole into which the movable part is movably engaged; and a stopper part located at the end of the elongated hole and provided on the guide part, which restricts the range of movement of the movable end of the gripping cylinder when the movable part abuts against it.
4. A construction machine according to claim 3, wherein the arm is provided with a bucket cylinder for rotating the bucket, and the gripping cylinder and the guide member are arranged on the lower surface of the arm opposite to the bucket cylinder.
5. The construction machine according to claim 3, characterized in that the guide portion is formed as a pair of vertical plates spaced apart in the width direction of the arm.
6. A construction machine according to claim 3, characterized in that the movable part comprises a detachable sliding part and is in sliding contact with the elongated hole via the sliding part.
7. The construction machine according to claim 6, wherein the sliding part is provided on a surface that slides against the elongated hole and scrapes off foreign matter adhering to the elongated hole, and is provided connected to the scraping part and is inclined from the inside to the outside of the elongated hole when the sliding part is attached to the moving part.