JP2013028988A - Work device of hydraulic shovel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To separate stone and others entered in a space between a front side link and an arm without catching the stone and others so as to prevent the front side link and the arm from being damaged by the stone and others.SOLUTION: The insides of left and right outside plates 26 located between a bucket side boss 22 and a cylinder side boss 24 of a front side link 21 are each provided with left and right inside inclined plates 27 which expand toward an upper face plate 13A of an arm 13 and which are inclined in a direction of the interval dimension between each other getting larger. Therefore, when a bucket 16 is rotated to the lower part and the front side link 21 is made to approach the upper face plate 13A of the arm 13 as stone R is entered between the front side link 21 and the upper face plate 13A of the arm 13, the stone R can be separated to the upper part of the front side link 21 along the inclined plane of left and right inside inclined plates 27.

Description

  The present invention relates to a working device for a hydraulic excavator that is preferably used for excavation work and crushing work of earth and sand.

  Generally, a hydraulic excavator is composed of a self-propelled lower traveling body, an upper revolving body that is turnably mounted on the lower traveling body, and a working device that is provided on the front side of the upper revolving body so as to be able to move up and down. It is roughly structured.

  The working device includes a boom that is provided on the front side of the revolving frame and is lifted and lowered by a boom cylinder, an arm that is provided on the distal end side of the boom and that is rotated by the arm cylinder, and a work implement cylinder that is provided on the distal end side of the arm. A work tool such as a bucket that is rotated by the rotation of the work tool cylinder, and a link mechanism that connects the front end side of the work tool cylinder to the work tool and the arm. This link mechanism includes a front link provided between the work tool and the work tool cylinder, and a rear link provided between the arm and the work tool cylinder (see, for example, Patent Document 1). ).

JP 2006-57313 A

  By the way, since the link mechanism by patent document 1 mentioned above has displaced the front side link by using the rear side link attached so that rotation with respect to the arm was a fulcrum, it rotated the work tool to the upper side with respect to the arm. Sometimes, the rear link rises and the front link is separated from the outer surface of the arm. On the other hand, when the work tool is rotated downward with respect to the arm, the rear link falls to the front side and the front link approaches the outer surface of the arm.

  Therefore, when the work tool is rotated upward and the front link is separated from the outer surface of the arm, a large gap is formed between them. And when the front link approaches the outer surface of the arm, stones or the like are bitten between the front link and the outer surface of the arm. Thereby, there exists a problem that a front side link and an arm will be shaved by the stone etc. which were bitten. On the other hand, it is conceivable to cover with a rubber wall plate so that stones do not enter between the front link and the arm, but in this case, there is a problem that the number of parts at the time of assembly and the work man-hour increase. is there.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to damage the front link and the arm by letting out stones or the like that have entered the gap between the front link and the arm so as not to get caught. It is an object of the present invention to provide a working device for a hydraulic excavator that can prevent the above-described problem.

  A working device for a hydraulic excavator according to the present invention includes a boom that is provided on a body of the hydraulic excavator and is lifted and lowered by a boom cylinder, an arm that is provided on a tip side of the boom and is rotated by an arm cylinder, and a tip side of the arm A work tool that is rotated by a work tool cylinder, and a link mechanism that connects a distal end side of the work tool cylinder to the work tool and the arm, and the link mechanism includes the work tool and the work tool. A front link provided between the cylinder and a rear link provided between the arm and the work tool cylinder.

  In order to solve the above-mentioned problem, the feature of the configuration adopted by the invention of claim 1 is that the front link of the link mechanism is spaced apart in the left and right directions between the work tool and the work tool cylinder. The left and right inner inclined plates are provided on the inner side of the left and right outer plates provided in this manner, and are inclined toward the outer surface of the arm in the direction in which the distance dimension increases.

  According to a second aspect of the present invention, the front link of the link mechanism is connected to the work tool side boss connected to the work tool via a connection pin, to the work tool cylinder and the rear link via the connection pin. A cylinder-side boss, the left and right outer plates connecting the work tool-side boss and the cylinder-side boss, and provided on the inner side of each of the outer plates, and expanded toward the outer surface of the arm. It is constituted by the left and right inner inclined plates.

  According to a third aspect of the present invention, the left and right outer plates and the left and right inner inclined plates forming the front link are joined to each other at the inner ends located on the outer surface side of the arm. In the outer end side away from the outer surface, a connecting plate for connecting between them is provided.

  According to the first aspect of the present invention, the left and right inner inclined plates provided inside the left and right outer plates forming the front link are inclined toward the outer surface of the arm in the direction in which the interval dimension increases. Yes. Therefore, when the work tool is rotated upward with respect to the arm and the front link is separated from the outer surface of the arm, stones, concrete pieces, etc. enter between them, and in this state, the work tool is moved downward. If the front link rotates and approaches the outer surface of the arm, the stones that have entered between the front link and the outer surface of the arm can be moved to the left, without biting between the front link and the arm. It can escape to the upper side of the front link along the inclined surface by the right inner inclined plate.

  As a result, even if stones enter between the front link and the outer surface of the arm during excavation work, crushing work, etc., these stones can escape along the inner inclined plates. It is possible to prevent damage such as wear of the front side link and the arm due to biting of the like, and to improve reliability and life.

  According to the invention of claim 2, the work tool side boss and the cylinder side boss can be firmly connected by the left and right outer plates and the left and right inner inclined plates. On this, even if there is a possibility that the front link may approach the outer surface of the arm and bite stones etc., the left and right inner inclined plates let this stone etc. escape to the opposite side of the arm along the inclined surface be able to.

  According to invention of Claim 3, the edge located in the outer surface side of an arm can be formed in an acute angle by joining the inner edge part of an outer side board, and the inner edge part of an inner side inclination board. Thereby, it is possible to make it difficult to bite stones or the like between the outer plate, the inner inclined plate, and the outer surface of the arm. Furthermore, by connecting the outer end portion of the outer plate and the outer end portion of the inner inclined plate by a connecting plate, a cylindrical body having a triangular cross section having strength is formed by the outer plate, the inner inclined plate and the connecting plate. It is possible to connect the work tool side boss and the cylinder side boss more firmly.

It is a front view showing a hydraulic excavator provided with a work device to which a front side link by a 1st embodiment of the present invention is applied. It is a perspective view which expands and shows an arm, a link mechanism, a bucket cylinder, etc. It is the expansion perspective view which looked at the front side link in FIG. It is the expansion perspective view which looked at the front side link of Drawing 3 from the lower part alone. It is a front view which shows the front side link of FIG. 3 alone. It is a top view which shows the front side link of FIG. 3 alone. It is an expanded sectional view of the front side link seen from the arrow VII-VII direction in FIG. It is operation | movement explanatory drawing which shows the state in which the stone etc. entered into the clearance gap formed between an arm and a front side link by rotating a bucket to the upper side. It is operation | movement explanatory drawing which shows the state which the stone etc. which entered into the clearance gap between an arm and a front side link are escaping when a bucket is rotated below. It is sectional drawing which looked at the state which the stone etc. are moving along the left and right inner inclination board from the arrow XX direction in FIG. It is the expansion perspective view which looked at the front side link by the 2nd Embodiment of this invention independently from the upper side. It is the expansion perspective view which looked at the front side link of Drawing 11 from the lower part alone. It is an expanded sectional view of the front side link seen from the arrow XIII-XIII direction in FIG.

  Hereinafter, a working device for a hydraulic excavator according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  First, FIGS. 1 to 10 show a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a crawler-type hydraulic excavator. The hydraulic excavator 1 is mounted on a self-propelled lower traveling body 2 and the lower traveling body 2 so as to be able to turn. The upper revolving body 3 to be configured and a work device 11 (described later) provided on the front side of the upper revolving body 3 so as to be able to move up and down are roughly constituted.

  Here, the upper revolving structure 3 is attached to a revolving frame 4 provided on the lower traveling body 2 so as to be revolving, a cab 5 mounted on the left front side of the revolving frame 4, and a rear portion of the revolving frame 4. A counterweight 6 that balances the weight with a work device 11 described later and an engine (not shown) mounted on the revolving frame 4 are roughly configured. The cab 5 is for an operator to board, and is provided with a driver's seat on which the operator is seated, various operation levers and the like (none of which are shown).

  Reference numeral 11 denotes a working device provided on the front side of the upper swing body 3 so as to be able to move up and down. This working device 11 performs, for example, excavation work of earth and sand, and is roughly constituted by a boom 12, an arm 13, a bucket 16, a boom cylinder 17, an arm cylinder 18, a bucket cylinder 19, and a link mechanism 20 which will be described later.

  Reference numeral 12 denotes a boom that constitutes the working device 11, and the boom 12 is attached to the front side of the revolving frame 4 so that the foot portion on the base end side can move up and down. The boom 12 has an intermediate portion bent in a substantially L shape, and a proximal end side of an arm 13 described later is rotatably attached to a distal end portion. The boom 12 is provided with an arm cylinder bracket 12A that is positioned substantially on the upper surface side in the middle of the length direction, and a tube 18A of an arm cylinder 18 to be described later is turnable on the arm cylinder bracket 12A. Installed. Further, boom cylinder bosses 12B (only the left side is shown) are provided on the left and right side surfaces at substantially the middle part in the length direction of the boom 12, and each boom cylinder boss 12B will be described later. The tip of the rod 17B of the boom cylinder 17 is rotatably attached.

  Reference numeral 13 denotes an arm rotatably provided at the tip of the boom 12. The arm 13 includes an upper surface plate 13A as an outer surface located on the upper side in a state where the working device 11 is extended, and a lower surface plate located on the lower side. 13B and a left side plate 13C and a right side plate 13D (see FIGS. 2 and 10) positioned between them are formed as an elongated box-like body (square tube body) having a square cross section. The base of the arm 13 is attached to the tip of the boom 12 so as to be rotatable via a connecting pin 14.

  An arm cylinder bracket 13E is provided at the base end portion of the arm 13, and a distal end of a rod 18B of an arm cylinder 18, which will be described later, is rotatably attached to the arm cylinder bracket 13E via a connecting pin 15. . Further, a bucket cylinder bracket 13F is provided on the base end side of the upper surface plate 13A of the arm 13, and a tube 19A base end of a bucket cylinder 19 to be described later is connected to the bucket cylinder bracket 13F via a connecting pin 15. It is pivotally mounted.

  Further, as shown in FIG. 2, a cylindrical bucket boss 13 </ b> G is provided at the tip of the arm 13. A bracket 19C of a bucket 16 described later is rotatably connected to the bucket boss portion 13G via a connecting pin 14.

  Further, a link boss portion 13H is provided on the distal end side of the arm 13 so as to be located on the base end side from the bucket boss portion 13G. The link boss portion 13H is a cylindrical body extending in the left and right directions. The left and right side plates 13C and 13D are provided through. A rear link 31, which will be described later, is rotatably connected to the link boss 13H via a connecting pin 15.

  Reference numeral 16 denotes a backhoe-type bucket rotatably provided at the distal end portion of the arm 13, and the bucket 16 constitutes one of the working tools attached to the distal end portion of the working device 11. The bucket 16 is roughly constituted by a bottom plate 16A formed to be curved in a concave shape, and side plates 16B fixed to both the left and right sides of the bottom plate 16A. On the base end side of the bottom plate 16A, an arm bracket 16C and a link bracket 16D are erected so as to be continuous. As shown in FIG. 10, the arm bracket 16 </ b> C of the bucket 16 is rotatably connected to the bucket boss portion 13 </ b> G of the arm 13 via a connecting pin 14. Further, the link bracket 16D is rotatably connected to a bucket-side boss 22 of the front link 21 described later via a connection pin 15.

  Reference numeral 17 denotes left and right boom cylinders (only one on the left is shown) provided between the revolving frame 4 and the boom 12, and each boom cylinder 17 moves the boom 12 up and down. The boom cylinder 17 is generally composed of a tube 17A and a rod 17B that protrudes from the tip of the tube 17A so as to expand and contract in the axial direction. In the boom cylinder 17, the base end portion of the tube 17 </ b> A is rotatably connected to the turning frame 4, and the distal end portion of the rod 17 </ b> B is rotatably connected to the boom cylinder boss portion 12 </ b> B of the boom 12.

  An arm cylinder 18 is provided between the boom 12 and the arm 13, and the arm cylinder 18 rotates the arm 13 with respect to the boom 12. The arm cylinder 18 is generally composed of a tube 18A and a rod 18B in the same manner as the boom cylinder 17. The arm cylinder 18 is connected to the arm cylinder bracket 12A of the boom 12 via the connecting pin 15 so that the proximal end of the tube 18A is pivotable, and the tip of the rod 18B is connected to the arm 13 via the connecting pin 15. The arm cylinder bracket 13E is rotatably connected.

  Reference numeral 19 denotes a bucket cylinder as a working tool cylinder provided between the arm 13 and a link mechanism 20 described later. The bucket cylinder 19 rotates the bucket 16 via the link mechanism 20. Further, the bucket cylinder 19 is roughly composed of a tube 19A and a rod 19B, almost the same as the boom cylinder 17. The bucket cylinder 19 has a proximal end portion of the tube 19A connected to the bucket cylinder bracket 13F of the arm 13 via the connecting pin 15 so as to be rotatable, and a distal end portion of the rod 19B connected to the front link via the connecting pin 25. 21 and the rear link 31 are rotatably connected.

  Next, the configuration of the link mechanism 20 of the work device 11 that is a characteristic part of the present embodiment will be described in detail.

  That is, 20 indicates a link mechanism provided on the tip side of the arm 13. The link mechanism 20 connects the rod 19 </ b> B of the bucket cylinder 19 to the bucket 16 and the arm 13 in order to transmit the power of the bucket cylinder 19 to the bucket 16. As shown in FIGS. 2 to 10, the link mechanism 20 increases the rotation angle of the bucket 16, and is roughly configured by a front link 21, connecting pins 23 and 25, and a rear link 31 described later. Yes.

  Reference numeral 21 denotes a front side link provided between the bucket 16 and the bucket cylinder 19. The front link 21 has an overall skeleton that is substantially U-shaped. As shown in FIGS. 3 to 7, the front side link 21 is roughly constituted by a bucket side boss 22, a cylinder side boss 24, an outer side plate 26, an inner inclined plate 27, and reinforcing members 29 and 30 which will be described later.

  Reference numeral 22 denotes a bucket-side boss provided on the bucket 16 side of the front link 21. The bucket-side boss 22 is formed as a cylindrical body extending in the left and right directions as shown in FIGS. 3, 4, and 6. Yes. The bucket-side boss 22 is pivotally attached to the base end side of the bucket 16 by inserting the connecting pin 23 in a state where the link bracket 16D of the bucket 16 is disposed at both ends in the axial direction. ing.

  Reference numeral 24 denotes a cylinder-side boss provided on the bucket cylinder 19 side of the front link 21, and the cylinder-side boss 24 is configured to rotatably connect the bucket cylinder 19 and a rear link 31 described later. The cylinder-side boss 24 is composed of two cylindrical bodies 22A arranged coaxially so as to be parallel to a position separated from the bucket-side boss 22 by a predetermined dimension. The cylinder-side bosses 24 are arranged in such a state that one end side of the rear link 31 is arranged at the outer end portion in the axial direction of each cylindrical body 24A, and the tip of the rod 19B of the bucket cylinder 19 is arranged between each cylindrical body 24A. By inserting the connecting pin 25 over the front link 21, the bucket cylinder 19 and the rear link 31 can be rotatably connected.

  A left and right outer plate 26 is provided between the bucket 16 and the bucket cylinder 19, that is, between the bucket side boss 22 and the cylinder side boss 24. The left and right outer plates 26 are made of a substantially rectangular plate, and the bosses 22 and 24 are parallel to each other at the left and right outer positions separated in the axial direction of the bosses 22 and 24. It extends in a direction perpendicular to the 24 axes. Each outer plate 26 has a front portion fixed to the end side of the bucket-side boss 22 using welding means, and a rear portion close to the outer end portion side of the cylindrical body 24A of the cylinder-side boss 24. Similarly, it is fixed using welding means. Further, in each outer plate 26 made of a substantially rectangular plate body, the end edge of the arm 13 on the upper surface plate 13A side is the inner end portion 26A, and the end edge of the arm 13 away from the upper surface plate 13A is the outer end portion 26B. It has become.

  Reference numeral 27 denotes left and right inner inclined plates provided inside the left and right outer plates 26. The left and right inner inclined plates 27 extend along the outer plate 26 between the bucket-side boss 22 and a first reinforcing member 29 described later. The inner inclined plate 27 includes a slope portion 27A located on the upper surface plate 13A side of the arm 13 and a vertical surface portion 27B continuous to the slope portion 27A at a position away from the arm 13.

  Here, as shown in FIG. 7, the inclined surface portion 27 </ b> A of each inner inclined plate 27 is linearly inclined in the direction in which the distance dimension increases toward the upper surface plate 13 </ b> A of the arm 13. That is, the inclined surface portion 27 </ b> A is an inclined surface that is inclined with respect to the outer plate 26 by an angle α. In this case, in each slope portion 27A, the inner end portion 27C located on the upper surface plate 13A side of the arm 13 is fixed to the inner end portion 26A of the outer plate 26 using welding means or the like. Thereby, the inner inclined plate 27 is arranged in a V-shaped cross section with respect to the outer plate 26.

  Therefore, as shown in FIG. 8, when the bucket 16 is rotated upward with respect to the arm 13, the front link 21 is separated from the arm 13. At this time, stones, concrete pieces, metal pieces or the like (hereinafter, representatively referred to as stone R) may enter between the front link 21 and the upper surface plate 13A of the arm 13. In this state, as shown in FIG. 9, when the bucket 16 is rotated downward, the front link 21 approaches the upper surface plate 13A of the arm 13, and the stone R is moved between the front link 21 and the upper surface plate 13A. Will be pinched. However, as shown in FIG. 10, the left and right inner inclined plates 27 follow the inclined surfaces of the stone R that have entered between the front link 21 and the upper surface plate 13A of the arm 13 without being bitten. It can escape to the upper side of the front link 21. Moreover, since the joint between the inner end 27C of the inner inclined plate 27 and the inner end 26A of the outer plate 26 is formed at an acute angle, the resistance when the stone R comes into contact can be further reduced. The stone R can be moved smoothly.

  Further, a connecting plate 28 that connects the inner inclined plate 27 and the outer plate 26 is provided at the outer end portion 27D of the inner inclined plate 27 that is separated from the upper surface plate 13A of the arm 13. The connecting plate 28 is formed as a strip-shaped plate extending substantially over the entire length of the outer plate 26, and the widthwise ends thereof are the outer end portion 27 </ b> D of the inner inclined plate 27 and the outer end portion of the outer plate 26. It is fixed to 26B using welding means. In this case, the outer end 26B of the outer plate 26 and the outer end 27D of the inner inclined plate 27 are connected by the connecting plate 28, so that the outer plate 26, the inner inclined plate 27 and the connecting plate 28 have strength. A cylindrical body having a triangular cross section can be formed, and the bucket boss 22 and the cylinder boss 24 can be firmly connected.

  Reference numeral 29 denotes a first reinforcing member provided on the front link 21, and the first reinforcing member 29 is provided between the cylinder-side boss 24 and the inner inclined plate 27. The first reinforcing member 29 is formed by bending a rectangular plate into a U shape. The first reinforcing member 29 has two end edges on the opening side fixed to the respective cylinders 24A of the cylinder side boss 24, and the left and right inner inclined plates 27 are provided between the end edges and the arc portion. It is fixed. Thereby, the first reinforcing member 29 has a strength of the front link 21, particularly a strength on the cylinder side boss 24 side, so that the entire front link 21 is not twisted and the two cylindrical bodies 24 </ b> A are not displaced. Can be increased.

  Reference numeral 30 denotes a second reinforcing member provided on the front link 21, and the second reinforcing member 30 is located near the bucket-side boss 22 and extends between the left and right outer plates 26 and the inner inclined plate 27. Is provided. The second reinforcing member 30 is formed as a cylindrical body (bar-shaped body) extending in the left and right directions. The second reinforcing member 30 is located between the bucket-side boss 22 and the first reinforcing member 29 and penetrates the left and right outer plates 26 and the inner inclined plate 27 in the left and right directions, The plate 26 and the inner inclined plate 27 are fixed using welding means. Thereby, the second reinforcing member 30 cooperates with the first reinforcing member 29 so that the entire front link 21 is not twisted, in particular, the strength of the front link 21, particularly the strength on the bucket boss 22 side. Can be increased.

  Reference numeral 31 denotes two left and right rear links attached to the front link 21 and the arm 13, and each rear link 31 is a cylinder of the front link 21 at one end in the length direction via a connecting pin 25. The other boss is connected to the link boss 13H of the arm 13 via the connecting pin 15 so as to be rotatable.

  The hydraulic excavator 1 according to the first embodiment has the above-described configuration. Next, an operation when the hydraulic excavator 1 is operated to perform work will be described.

  First, the operator gets into the cab 5 and sits in the driver's seat. By operating the operation lever for traveling in this state, the crawler of the lower traveling body 2 can be driven to move the hydraulic excavator 1 forward or backward. In addition, an operator seated in the driver's seat can perform work such as excavation of earth and sand by operating the operation lever for work to move the working device 11 up and down.

  When performing this excavation work or the like of the earth and sand, a stone R falls on the working device 11, and a part of the stone R is located in the gap between the front link 21 and the upper surface plate 13A of the arm 13 as shown in FIG. May get in. In this state, the operation is continued, and as shown in FIG. 9, when the bucket 16 is rotated downward, the front link 21 approaches the upper surface plate 13A of the arm 13, and between the front link 21 and the upper surface plate 13A. The stone R will be sandwiched between them. As described above, when the hard stone R is bitten, the front side link 21 and the upper surface plate 13A of the arm 13 are worn.

  However, in the first embodiment, the front link 21 is connected to the bucket bracket 16D of the bucket 16 via the connection pin 23, the bucket cylinder 19 and the left and right rear links 31. Cylinder side boss 24 connected to each other via a connecting pin 25, and the bucket side boss 22 and the cylinder side boss spaced apart in the left and right directions between the bucket side boss 22 and the cylinder side boss 24. 24, left and right outer plates 26, and left and right inclined plates provided inwardly of the outer plates 26 so as to expand toward the upper surface plate 13A of the arm 13 so that the distance dimension increases. A right inner inclined plate 27 is used.

  Accordingly, when the stone 16 is inserted between the front link 21 and the upper surface plate 13A of the arm 13, the bucket 16 is rotated downward, and the front link 21 is brought closer to the upper surface plate 13A of the arm 13, The stone R can escape to the upper side of the front link 21 along the inclined surface by the left and right inner inclined plates 27 without biting between the front link 21 and the arm 13.

  As a result, the stone R that has entered between the front side link 21 and the upper surface plate 13A of the arm 13 during excavation work or the like can escape along the inner inclined plates 27. Damage to the front link 21 and the upper surface plate 13A of the arm 13 due to the wear can be prevented, and the reliability and life can be improved.

  Further, the left and right outer plates 26 and the left and right inner inclined plates 27 can firmly connect the bucket boss 22 and the cylinder boss 24. On this, the stone R that has entered the area surrounded by the outer side plate 26, the bucket side boss 22, and the cylinder side boss 24 can be released to the side opposite to the arm 13 by each inner inclined plate 27.

  Furthermore, since the joint portion between the inner end portion 27C of the inner inclined plate 27 and the inner end portion 26A of the outer plate 26 is formed at an acute angle, the resistance when the stone R contacts can be further reduced. Thereby, it is possible to make it difficult for the stone R to be bitten between the outer side plates 26, the inner inclined plate 27 and the upper surface plate 13A of the arm 13, and the stone R can be smoothly moved and released. In addition, the inner end portion 26A of the outer plate 26 and the inner end portion 27C of the inner inclined plate 27 are connected by the connecting plate 28 so that the outer plate 26, the inner inclined plate 27 and the connecting plate 28 have a stronger cross section. A triangular cylindrical body can be formed, and the bucket-side boss 22 and the cylinder-side boss 24 can be more firmly connected.

  Next, FIGS. 11 to 13 show a second embodiment of the present invention. A feature of the present embodiment is that a tubular body having a triangular cross section composed of an outer plate, an inner inclined plate, and a connecting plate is provided over the entire length between the work tool side boss and the cylinder side boss. It is in. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In FIG. 11, reference numeral 41 denotes a front link according to the second embodiment, and 42 denotes left and right inner inclined plates according to the second embodiment provided on the front link 41. The left and right inner inclined plates 42 have a slope portion 42A and a vertical surface portion 42B in substantially the same manner as the inner inclined plate 27 according to the first embodiment. The outer end portion 42D is fixed to the connecting plate 28, and is fixed to the end portion 26A. However, each inner inclined plate 42 according to the second embodiment is provided over the entire length between the bucket-side boss 22 and the cylinder-side boss 24, and therefore the inner inclined plate according to the first embodiment. 27. In this case, the U-shaped first reinforcing member 29 according to the first embodiment is omitted.

  Reference numeral 43 denotes a first reinforcing member according to the second embodiment provided in place of the first reinforcing member 29. As shown in FIGS. 12 and 13, the first reinforcing member 43 is formed of a substantially trapezoidal plate, and is located near the cylinder-side boss 24 and uses welding means for the left and right inner inclined plates 42. It is fixed. Thereby, the 1st reinforcement member 43 can cooperate with the 2nd reinforcement member 30, and can raise the intensity | strength of the front side link 41. FIG.

  Thus, also in the second embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, according to the second embodiment, since the left and right inner inclined plates 42 are provided over the entire length between the bucket side boss 22 and the cylinder side boss 24, the bucket side boss 22 and the cylinder side are provided. The strength of the cylindrical body having a triangular cross section connecting the boss 24 can be increased.

  In the first embodiment, the case where the outer plate 26, the inner inclined plate 27, and the connecting plate 28 are separately provided and fixed to each other using welding means is illustrated. However, the present invention is not limited to this. For example, the outer plate and the inner inclined plate may be formed by bending a single plate, and the connecting plate may be fixed thereto. Similarly, the inner inclined plate and the connecting plate may be formed from a single plate, and the outer plate and the connecting plate may be formed from a single plate. These configurations can be similarly applied to the second embodiment.

  Further, in the first embodiment, an example in which the inclined surface portion 27A of the inner inclined plate 27 is linearly inclined in the direction in which the distance dimension increases toward the upper surface plate 13A of the arm 13 will be described as an example. did. However, the present invention is not limited to this. For example, the slope portion 27A of the inner inclined plate 27 may be formed as a curved arc surface. This configuration can be similarly applied to the second embodiment.

  Further, in the first embodiment, a case in which two pieces of the first reinforcing member 29 and the second reinforcing member 30 are provided on the front link 21 is illustrated. However, the present invention is not limited to this. For example, the configuration may be such that the reinforcing member is eliminated. Moreover, it is good also as a structure which provides one or three or more reinforcement members. These configurations can be similarly applied to the second embodiment.

  Furthermore, in each embodiment, the working device 11 provided in the crawler type hydraulic excavator 1 as the working device of the hydraulic excavator and including the bucket 16 as the working tool has been described as an example. However, the present invention is not limited to this, and may be applied to, for example, a working apparatus for a hydraulic excavator provided with a wheel-type lower traveling body. In addition, the present invention can be applied to a working device provided with a crushing device for crushing a rock or a building, a cutter, or the like as a working tool.

1 Hydraulic excavator 2 Lower traveling body (vehicle body)
3 Upper swing body (car body)
11 Working device 12 Boom 13 Arm 13A Top plate (outer surface)
16 bucket (work implement)
17 Boom cylinder 18 Arm cylinder 19 Bucket cylinder (work implement cylinder)
20 Link mechanism 21, 41 Front link 22 Bucket side boss (work implement side boss)
23, 25 Connecting pin 24 Cylinder side boss 26 Outer plate 26A, 27C, 42C Inner end portion 26B, 27D, 42D Outer end portion 27, 42 Inner inclined plate 27A, 42A Inclined portion 27B, 42B Vertical surface portion 28 Connecting plate 29, 43 First reinforcing member 30 Second reinforcing member 31 Rear link α Inclination angle of inner inclined plate

Claims (3)

A boom provided on the body of the hydraulic excavator and moved up and down by a boom cylinder, an arm provided on the tip side of the boom and rotated by an arm cylinder, and rotated by a work tool cylinder provided on the tip side of the arm. A work tool, and a link mechanism for connecting the front end side of the work tool cylinder to the work tool and the arm,
The link mechanism is a hydraulic excavator configured by a front link provided between the work tool and the work tool cylinder, and a rear link provided between the arm and the work tool cylinder. In work equipment,
The front link of the link mechanism has a spacing dimension toward the outer surface of the arm on the inner side of the left and right outer plates provided to be separated in the left and right directions between the work tool and the work tool cylinder. A working apparatus for a hydraulic excavator, characterized in that left and right inner inclined plates are provided so as to be inclined in a direction in which the pressure increases.   The front link of the link mechanism includes a work tool side boss connected to the work tool via a connection pin, a cylinder side boss connected to the work tool cylinder and the rear link via a connection pin, The left and right outer plates that connect the work tool side boss and the cylinder side boss, and the left and right inner slopes that are provided on the inner side of each outer plate and expand toward the outer surface of the arm. The working device for a hydraulic excavator according to claim 1, comprising a plate. The left and right outer plates and the left and right inner inclined plates that form the front link are joined to each other at the inner ends located on the outer surface side of the arm,
The working device for a hydraulic excavator according to claim 1 or 2, wherein a connecting plate is provided on an outer end portion side away from an outer surface of the arm to connect the arms.

Images