JP2007277930A - Working device of construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a burden in the work phase and the cost phase, by easily providing both a bearing device endurable against a load and a bearing device superior in abrasion resistance, without replacing an arm. <P>SOLUTION: This working device is constituted by installing an abrasion resistant top 32 having a durable bearing device 34 having higher durability against abrasion than a bearing device 14 of a standard specification arranged on the tip side of the arm 13, on the tip side of the arm 13 instead of a bucket 15. Thus, when performing work on which the load acts, the bucket 15 is directly installed on the bearing device 14 of the arm 13. While, when performing work of fearing abrasion by intrusion of sediment, the abrasion resistant top 32 having the durable bearing device 34 is installed on the tip side of the arm 13, and the bucket 15 is installed in this durable bearing device 34. Thus, both the bearing device 14 endurable against the load and the durable bearing device 34 superior in abrasion resistance can be provided by simple work. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a working device for a construction machine that performs various operations by, for example, rotating a work tool on the distal end side of an arm.

  In general, a working device mounted on a hydraulic excavator as a construction machine includes a boom that can be raised and lowered on the front side of a revolving frame, an arm that can be turned on the tip side of the boom, A bucket that is rotatably provided at the front end side, a boom cylinder that is provided between the swing frame and the boom and moves the boom up and down, and is provided between the boom and the arm. An arm cylinder to be moved, a link mechanism located on the tip side of the arm and connected to the arm and the bucket, and provided between the arm and the link mechanism, and the bucket is rotated through the link mechanism. It is roughly constituted by a bucket cylinder to be moved.

  Also, a bearing device is attached to the tip end side of the arm, and a pair of brackets are provided on the bucket with an interval sandwiching the arm bearing device. And it is set as the structure which attaches a bucket with respect to the said arm so that rotation is possible by inserting a connecting pin in the bearing apparatus of an arm from the bracket of a bucket (for example, refer patent document 1).

JP 2001-115479 A

  Here, the excavator may perform excavation work in mudland, discharge work of underwater sediment and accumulated mud, etc., and in such work, the tip side of the arm will be submerged in the mud. . In this case, even if one seal member is attached to the bearing device, there is a problem that minute earth and sand passes through the seal member due to the influence of water pressure, fluidity, etc., and enters the sliding portion to cause wear. is there.

  Therefore, other work devices include a bearing device that prevents minute earth and sand from entering the tip of the arm and has improved durability against wear. The bearing device includes a boss member, an outer bush fitted into the boss member, an outer bush fitted to the outer bush so as to be slidable, and an inner bush fitted to the connecting pin on the inner peripheral side. A first seal member that seals between the end of the inner bush and the end of the boss member; and a second seal that seals between the end of the inner bush and the outer periphery of the connecting pin It is comprised by the member (for example, refer patent document 2).

JP-A-11-107305

  By the way, in the bearing device according to Patent Document 2 described above, an outer bush and an inner bush are provided in the boss member, and a first seal member is provided between the inner bush and the boss member, and between the inner bush and the connecting pin. It is set as the structure which provides a 2nd sealing member. As a result, the bearing device prevents intrusion of minute earth and sand by the two seal members, and the durability against wear in excavation work in a muddy area, discharge work in water, and the like is higher than that of the bearing apparatus according to Patent Document 1. Can also be increased.

  However, the double bush structure employed by the bearing device of Patent Document 2 is not only suitable for excavation work on the ground where a large load acts, in addition to being expensive and having a large number of parts. Therefore, when performing an operation in which a load is applied, the arm must be exchanged with a conventional bearing device (the bearing device according to Patent Document 1), which is a burden on the work surface and cost. There is a problem that increases.

  In addition, the bearing device provided on the distal end side of the arm may wear the bush or the like due to long-term use, or may be damaged due to unreasonable work, falling rocks, etc. In this case, it is necessary to replace the bearing device. is there. However, in order to replace the bearing device, it is necessary to cut the bearing device welded to the tip end side of the arm, and to re-weld and attach a new bearing device to the tip end side of the arm. .

  Furthermore, if the tip of the arm is damaged, the entire arm must be replaced with another arm equipped with a new bearing device, which requires a lot of labor for the replacement. There is a problem that it ends up.

  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 easily provide both a bearing device that can withstand a load and a bearing device that has excellent wear resistance without exchanging the arm. It is an object of the present invention to provide a working device for a construction machine that can be obtained and can reduce the work and cost burdens.

  Another object of the present invention is to provide a new bearing device on the distal end side of the arm by a simple operation without performing a welding operation, an arm replacement operation, or the like when the bearing device is worn or damaged. It is an object of the present invention to provide a construction machine working apparatus that can perform the above.

  A working device for a construction machine according to the present invention includes a boom provided on the vehicle body of the construction machine so as to be able to move up and down, and an arm provided with a bearing device for pin coupling on the tip side of the boom. And a working tool that is rotatably attached to the distal end side of the arm via a bearing device.

  In order to solve the above-mentioned problem, the feature of the configuration adopted by the invention of claim 1 is that the wear-resistant top provided with a durable bearing device having higher durability against wear than the bearing device, and the work tool. In place of the arm, it is prepared in advance so that it can be attached to the tip side of the arm, and when the wear-resistant top is attached to the tip side of the arm, the durable bearing device is used for the wear-resistant top. The work tool is attached.

  According to a second aspect of the present invention, another end of the arm is provided with a bearing device for attaching a link mechanism for transmitting the expansion / contraction operation of the work tool cylinder to the work tool. The present invention has a configuration in which a first mounting hole that is attached to the bearing device using a connecting pin and a second mounting hole that is attached to the other bearing device using a connecting pin are provided.

  According to a third aspect of the present invention, the wear-resistant top has substantially the same dimension as the distance between the first mounting hole and the second mounting hole and the distance between the durable bearing device and the first mounting hole. It is in having been set to.

  According to a fourth aspect of the present invention, the wear-resistant top durable bearing device includes a boss member provided on a tip side of the wear-resistant top, an outer bush fitted in the boss member, and an outer peripheral side on the outer side. An inner bush that is slidably fitted into the bush and has an inner peripheral side fitted to the connecting pin, and a first seal member that seals between the end of the inner bush and the end of the boss member; A double bush structure comprising a second seal member for sealing between the end of the inner bush and the outer periphery of the connecting pin is provided.

  According to a fifth aspect of the present invention, there is provided a construction machine working apparatus according to a fifth aspect of the present invention, wherein a boom is provided on the vehicle body of the construction machine so as to be able to move up and down, and is provided at the front end side of the boom so as to be rotatable. An arm in which the bearing device and the second bearing device are spaced apart from each other in the length direction; a work tool rotatably attached to the distal end side of the arm via the first bearing device; A work tool cylinder that is attached to the arm and has a free end as a distal end to operate the tool and extends in the vicinity of the work tool; and a telescopic operation of the work tool cylinder to transmit the work tool cylinder to the work tool. The distal end side of the working tool cylinder is constituted by a link mechanism that connects the working tool and the second bearing device at the distal end of the arm.

  In order to solve the above-described problem, the feature of the configuration adopted by the invention of claim 5 is that a replacement top that can be attached to the tip of the arm is prepared in advance instead of the work tool, and the replacement is performed. The top is a casing attached to the distal end side of the arm, a first attachment hole provided at a central position in the longitudinal direction of the casing and attached to the first bearing device of the arm using a connection pin, A second mounting hole provided on the base end side in the longitudinal direction of the casing and attached to the second bearing device of the arm using a connecting pin; and a replacement bearing device provided on the front end side of the casing. When the replacement top is attached to the distal end side of the arm, the working tool is attached to the replacement top using the replacement bearing device.

  According to the first aspect of the present invention, when performing leveling work on the ground, normal excavation work, etc., the work tool can be rotated on the bearing device of the arm without attaching the wear-resistant top to the arm. Install to. Thereby, a working tool can be attached to the normal bearing device which can endure a big load at the front end side of the arm.

  On the other hand, when performing work such as excavation work in a muddy area, discharge work of underwater sediment or accumulated mud soil, where there is concern about wear of the bearing device, the work tool is removed from the arm. Instead, a wear-resistant top equipped with a durable bearing device having high durability against wear is attached to the tip side of the arm. Thereby, a work tool can be attached to the endurance type bearing device excellent in wear resistance on the tip side of the arm.

  Therefore, both a normal bearing device and a durable bearing device with excellent wear resistance can be obtained by a simple operation of attaching and removing a wear-resistant top prepared in advance to the tip side of the arm. As a result, it is not necessary to replace the arm, and it is not necessary to prepare two arms, so that workability can be improved and the cost burden can be reduced.

  According to the invention of claim 2, a bearing device provided in advance on the tip end side of the arm and another bearing device are used, and one connecting pin is connected to the first mounting hole of the wear-resistant top and the arm bearing device. The other connecting pin is inserted into the second mounting hole of the wear-resistant top and the other bearing device of the arm. As a result, the wear-resistant top can be attached to the arm with a simple operation without any additional processing of the existing arm.

  According to the invention of claim 3, the distance between the first mounting hole and the second mounting hole provided in the wear-resistant top and the distance between the durable bearing device and the first mounting hole are substantially the same. Because of the size, the wear-resistant top can keep the protruding dimension from the tip of the arm to the durable bearing device short, and can be formed with a short overall length. Thereby, also when using an abrasion-resistant top, a working device can be formed in a lightweight and compact, and assembly workability, portability, etc. can be improved. Further, since the amount of rotation of the work tool when the work tool cylinder is expanded and contracted can be made substantially the same as when the work tool is directly attached to the arm, the operability and workability can be improved.

  According to the invention of claim 4, the durable bearing device having a double bush structure can seal between the boss member and the inner bush by the first seal member, and the inner bush by the second seal member. And the connection pin can be sealed. As a result, the two seal members can reliably and reliably prevent dirt and the like from entering the sliding surface between the outer bush and the inner bush over a long period of time. Can be improved.

  According to the invention of claim 5, when the bearing device provided on the distal end side of the arm is worn away by long-term use, or is damaged due to unreasonable work, falling rocks, etc., Install the replacement top with the replacement bearing device. As a result, a new replacement bearing device can be replaced with a work tool and installed on the distal end side of the arm by a simple operation without performing welding work, arm replacement work, etc. You can install the tool.

  The replacement top uses a first bearing device and a second bearing device provided in advance on the tip side of the arm, and the first mounting hole of the replacement top is connected to the first arm of the arm using a connecting pin. It can be attached to the bearing device, and the second mounting hole of the replacement top can be attached to the second bearing device of the arm using the connecting pin. As a result, the replacement top can be attached to the arm by a simple operation without separately processing the existing arm.

  Hereinafter, a working device for a hydraulic excavator will be described as an example of a working device for a construction machine applied to an embodiment of the present invention, and will be described in detail with reference to the accompanying drawings.

  First, FIGS. 1 to 12 show a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a hydraulic excavator as a construction machine. The hydraulic excavator 1 is a self-propelled crawler-type lower traveling body 2 and is mounted on the lower traveling body 2 so as to be able to turn. In addition, the upper revolving unit 3 constituting the vehicle body and a work device 11, 31 described later provided on the front side of the upper revolving unit 3 are roughly configured. Here, the upper swing body 3 includes a swing frame 4, a cab 5 mounted on the left front side of the swing frame 4, a counterweight 6 attached to the rear portion of the swing frame 4, an engine (not shown), and the like. It is configured to include.

  Next, 11 shows the working device according to the first embodiment provided on the front side of the upper swing body 3. The working device 11 performs various work with different environments and loads, such as excavation work in a muddy area, scooping work of mud in water, excavation work on a flat land, and a cliff. In this case, excavation work in mud and scooping out mud in water, although the load during the work is small, fine soil and sand enter the sliding part together with water due to the action of water pressure, fluidity, etc. There is concern about the wear of the sliding part. On the other hand, in excavation work on flat ground and cliffs, it is unlikely that a large amount of earth and sand will invade the sliding site, but the load due to impact during the work increases.

  Here, the working device 11 shown in FIGS. 1 to 3 is a form for carrying out work with a heavy load during work, for example, excavation work such as flat land, cliff, etc. 15 is directly attached. Further, the working device 31 shown in FIGS. 4 to 12 is a form for performing work in which minute earth and sand are likely to wear due to intrusion into the sliding portion, for example, muddy work and underwater work. A wear-resistant top 32 is attached to the tip end side of 13 instead of the bucket 15, and the bucket 15 is attached to the wear-resistant top 32.

  Therefore, in the first embodiment, first, a description will be given of the form of the standard specification work device 11 suitable for work in which a large load acts. The working device 11 of the standard specification is generally configured by a boom 12, an arm 13, a bucket 15, a bucket connecting pin 16, a link mechanism 17, a link connecting pin 18, a boom cylinder 19, an arm cylinder 20, a bucket cylinder 21 and the like which will be described later. ing.

  Reference numeral 12 denotes a boom whose base end is attached to the front side of the revolving frame 4 so as to be able to move up and down. The boom 12 is formed as a box structure having a hollow inside and a rectangular cross section, and is bent in a “h” shape as a whole. A boom cylinder mounting portion 12A (only the left side is shown) to which a rod 19B tip of a boom cylinder 19 to be described later is attached and a tube 20A base end of an arm cylinder 20 to be described later are attached to an intermediate portion in the length direction of the boom 12. Arm cylinder bracket 12B.

  Reference numeral 13 denotes an arm pivotably attached to the tip of the boom 12. The arm 13 is formed as a box structure having a hollow inside and a rectangular cross section by an upper flange 13A, a lower flange 13B, a left web 13C (shown in FIG. 7 and the like) and a right web 13D. As shown in FIG. 2, the upper flange 13 </ b> A and the lower flange 13 </ b> B gradually approach toward the distal end side of the arm 13, whereby the left web 13 </ b> C and the right web 13 </ b> D are tapered.

  In addition, an arm cylinder attachment portion 13E that protrudes rearward and is attached to the tip of the rod 20B of the arm cylinder 20 is provided at the base end portion of the arm 13. Further, on the base end side of the left and right webs 13C and 13D, a boom mounting portion 13F (only the right side is shown) is provided that is positioned on the lower flange 13B side and on which the tip end portion of the boom 12 is rotatably mounted. Yes. Further, a bucket cylinder bracket 13G for attaching a tube 21A base end of a bucket cylinder 21 described later is provided on the base end side of the upper flange 13A.

  On the other hand, as shown in FIG. 11, at the front end side of the left and right webs 13C and 13D, a link bearing device as another bearing device that rotatably supports a second link 17B of a link mechanism 17 described later. 13H is provided. A bearing device 14 described later is provided at the tip of the arm 13.

  Reference numeral 14 denotes a standard bearing device provided at the tip of the arm 13, and the bearing device 14 constitutes a part of the arm 13. The bearing device 14 supports the bucket 15 so as to be rotatable via a bucket connecting pin 16 described later. Here, as shown in FIG. 3, the standard-specific bearing device 14 has a large contact area with a bush 14 </ b> B (described later) in sliding contact with the outer peripheral surface of the bucket connecting pin 16, thereby causing an impact or the like generated during excavation. It has a structure that can be received and can withstand a large load.

  The standard bearing device 14 has a cylindrical boss member 14A attached to the tip of the arm 13 so as to extend leftward and rightward, and is fitted into the boss member 14A, and is bucket-connected to the inner peripheral side. A bush 14B into which the pin 16 is slidably inserted and a pair of seal members 14C mounted on the boss member 14A at both ends of the bush 14B are roughly constituted. Further, the boss member 14A and the bush 14B are provided with an oil supply passage 14D for filling the sliding surface between the bush 14B and the bucket connecting pin 16 with lubricating oil.

  Reference numeral 15 denotes a backhoe-type bucket that is rotatably provided at the distal end side of the arm 13, and the bucket 15 constitutes one of the working tools attached to the distal end portion of the working device 11. The bucket 15 includes a bottom plate 15A that is curved in a concave shape, a side plate 15B that is fixed to the left and right sides of the bottom plate 15A, and a left that is erected on the base end side of the bottom plate 15A with a gap therebetween, This is roughly constituted by the right bracket 15C.

  Each bracket 15C of the bucket 15 has an arm pin hole 15C1 and a link pin hole 15C2. Then, the bucket 15 is rotatably connected to the distal end side of the arm 13 by inserting a bucket connecting pin 16 described later into the bearing device 14 of the arm 13 from the arm pin hole 15C1 provided in each bracket 15C. Has been.

  Reference numeral 16 denotes a bucket connecting pin for attaching the bucket 15 to the tip side of the arm 13. This bucket connecting pin 16 is inserted into the bearing device 14 of the arm 13 from the arm pin hole 15C1 provided in each bracket 15C of the bucket 15 so that the bucket 15 can be rotated to the tip side of the arm 13. To be connected. The bucket connecting pin 16 can also be used when the bucket 15 is attached to a durable bearing device 34 of a wear-resistant top 32 described later.

  Reference numeral 17 denotes a link mechanism located on the tip side of the arm 13 and connected to the arm 13 and the bucket 15, and the link mechanism 17 increases the rotation angle of the bucket 15. The link mechanism 17 has a first link 17A, one end of which is rotatably connected to a link pin hole 15C2 provided in each bracket 15C of the bucket 15 via a link connecting pin 18, and one end of the link mechanism 17. The second link 17B is rotatably connected to a position sandwiching the other end of one link 17A via a connecting pin 17C. The other end of the second link 17B is rotatably attached to the link bearing device 13H of the arm 13 via a link connecting pin 18.

  Reference numeral 19 denotes two boom cylinders (only the right side is shown) provided between the revolving frame 4 and the boom 12, and each boom cylinder 19 moves the boom 12 up and down. In addition, the boom cylinder 19 has a proximal end of a tube 19 </ b> A attached to a front end portion of the revolving frame 4 so as to be rotatable, and a distal end of a rod 19 </ b> B attached to a boom cylinder attaching portion 12 </ b> A of the boom 12 so as to be rotatable.

  An arm cylinder 20 is provided between the boom 12 and the arm 13, and the arm cylinder 20 rotates the arm 13 with respect to the boom 12. Further, the arm cylinder 20 has a proximal end of the tube 20 </ b> A attached to the arm cylinder bracket 12 </ b> B of the boom 12 so as to be rotatable, and a distal end of the rod 20 </ b> B is attached to an arm cylinder mounting portion 13 </ b> E of the arm 13 so as to be rotatable. .

  Reference numeral 21 denotes a bucket cylinder provided between the arm 13 and the bucket 15. The bucket cylinder 21 rotates the bucket 15 at the tip of the arm 13. Further, the bucket cylinder 21 has a proximal end of a tube 21A rotatably attached to a bucket cylinder bracket 13G of an arm 13, and a distal end of a rod 21B rotates together with each link 17A, 17B to a connecting pin 17C of a link mechanism 17. It is mounted movably.

  In such a standard working device 11, a bucket 15 is attached to a standard bearing device 14 provided at the tip of an arm 13 via a bucket connecting pin 16. At this time, since the bearing device 14 rotatably supports the bucket connecting pin 16 by the bush 14B having a large contact area, the bearing device 14 can sufficiently receive the impact transmitted from the bucket 15. Thereby, the standard working device 11 is suitable, for example, for excavating a flat ground, a cliff, or the like, or for demolition of a building.

  Next, a description will be given of the form of the wear resistant work device 31 suitable for work in which earth and sand and moisture enter the sliding portion and wear, with reference to FIGS. 4 to 12. This wear resistant work device 31 is obtained by attaching a wear resistant top 32 and the like described later to the standard work device 11 described above. Specifically, a wear-resistant top 32 is attached to the distal end side of the arm 13 instead of the bucket 15, and the bucket 15 is attached to the durable bearing device 34 of the wear-resistant top 32 using the bucket connecting pin 16. Therefore, a wear resistant top 32 capable of easily changing the standard working device 11 to the wear resistant working device 31 will be described.

  Reference numeral 32 denotes a wear-resistant top that is detachably attached to the distal end side of the arm 13. This wear-resistant top 32 is used when performing work in which earth and sand or the like can wear due to intrusion into the sliding portion, for example, muddy work, underwater work, etc. Can be pivotally mounted. As a result, the wear-resistant top 32 suppresses the wear of the sliding portion when the bucket 15 is rotated, thereby extending the life. As shown in FIGS. 5 and 7, the wear-resistant top 32 is roughly constituted by a casing 33 and a durable bearing device 34 which will be described later.

  Reference numeral 33 denotes a casing of the wear-resistant top 32. As shown in FIGS. 8 and 9, the casing 33 is notched in a U-shape at the base end side and has a narrow end portion. Further, on the left and right side surfaces of the casing 33, a first mounting hole 33A, which is positioned at a substantially intermediate portion in the length direction and is mounted to the bearing device 14 of the arm 13 using a connecting pin 36 described later, It has a second mounting hole 33B which is located at the base end portion and is mounted to the link bearing device 13H of the arm 13 using the connecting pin 36. A bush (not shown) is inserted into each of the mounting holes 33A and 33B. Further, a durable bearing device 34 to be described later is attached to the tip of the casing 33.

  Here, the distance L1 between the first mounting hole 33A and the second mounting hole 33B and the distance L2 between the durable bearing device 34 and the first mounting hole 33A are set to substantially the same dimension. (L1 ≒ L2). Thereby, when the casing 33 is attached to the distal end side of the arm 13, the projecting dimension from the distal end of the arm 13 to the durable bearing device 34 can be kept short, and the overall length of the casing 33 can be shortened. .

  With this configuration, even when the wear-resistant top 32 is used, the work device 31 can be formed in a lightweight and compact manner, and assembly workability, portability, and the like can be improved. Further, since the entire length of the arm 13 including the wear-resistant top 32 can be kept short, the load acting on the arm 13, the bucket cylinder 21 and the like can be reduced. Furthermore, the amount (angle) by which the bucket 15 rotates via the link mechanism 17 when the bucket cylinder 21 is expanded and contracted can be made substantially the same as when the bucket 15 is directly attached to the arm 13. And workability can be improved.

  Reference numeral 34 denotes a durable bearing device provided at the tip of the casing 33. The durable bearing device 34 is attached to the tip of the arm 13 so as to be rotatable, in the same manner as the bearing device 14 of the standard specification. Is. However, the durable bearing device 34 has a structure that is more durable against wear than the standard bearing device 14.

  That is, as shown in FIG. 10, the durable bearing device 34 includes a cylindrical boss member 34A attached to the front end portion of the casing 33 so as to extend leftward and rightward, and both axial ends of the boss member 34A. The outer bush 34B that is fitted, the inner bush 34C that is slidably fitted in each outer bush 34B, and the inner peripheral side is fitted to the bucket connecting pin 16, the end of the inner bush 34C, and the boss A first seal member 34D that seals between the ends of the member 34A in two stages, a second seal member 34E that seals between the end of the inner bush 34C and the outer periphery of the bucket connecting pin 16, and the like Thus, a double bush structure is formed. The boss member 34A and the outer bush 34B are provided with an oil supply passage 34F for supplying lubricating oil to the sliding surface between the outer bush 34B and the inner bush 34C.

  Here, the durable bearing device 34 having a double bush structure has a sliding surface between the outer bush 34B and the inner bush 34C, and a two-stage first seal member at a portion communicating with the sliding surface from the outside. 34D and one-stage second seal member 34E are arranged. Thereby, it is possible to efficiently prevent minute earth and sand, water, and the like from entering the sliding surface by the seal members 34D and 34E, and the durability of the outer bush 34B and the inner bush 34C is improved and the life is extended. be able to.

  Reference numeral 35 denotes two additional links constituting the wear-resistant top 32. One end of the additional link 35 is rotatably connected to the other end of the first link 17A of the link mechanism 17 and the tip of an additional rod 37 described later, and the other end rotates to the first mounting hole 33A of the casing 33. It is mounted movably. Here, the additional link 35 substantially has a distance L1 between the first mounting hole 33A and the second mounting hole 33B of the casing 33 and a distance L2 between the durable bearing device 34 and the first mounting hole 33A. By setting the same dimension, the same length and shape as the second link 17B used in the existing link mechanism 17 can be used as a common part.

  Reference numeral 36 denotes four long connecting pins. Two of the four connecting pins 36 are used to attach the casing 33 of the wear-resistant top 32 to the distal end side of the arm 13. One of the two connecting pins 36 is connected to the bearing device 14 of the arm 13 with the first mounting hole 33A of the casing 33 and the other end of the additional link 35, as shown in FIGS. By positioning and being inserted in this state, the casing 33 of the wear-resistant top 32 is attached to the arm 13, and the additional link 35 is rotatably attached to the casing 33. The other connecting pin 36 positions the second mounting hole 33B of the casing 33 and the other end of the second link 17B of the link mechanism 17 in the link bearing device 13H of the arm 13 in this state. The casing 33 is attached to the arm 13 by being inserted, and the second link 17B is rotatably attached to the casing 33.

  The other connecting pin 36 is used to connect the first link 17 </ b> A of the link mechanism 17, the additional link 35, and an additional rod 37 described later. Still another connecting pin 36 is used to connect the second link 17B of the link mechanism 17 to the tip of the rod 21B of the bucket cylinder 21 and the additional rod 37.

  As described above, the four connecting pins 36 are formed to be longer than the link connecting pins 18 and the like because the casing 33 of the wear-resistant top 32 is wider than the arm 13. Further, two of the connecting pins 36 do not use any additional fastening means or the like, and wear resistance using the bearing device 14 and the link bearing device 13H provided in advance on the standard specification arm 13. The casing 33 of the top 32 can be easily fixed and attached, and can be easily removed.

  Reference numeral 37 denotes an additional rod that connects the first link 17A of the link mechanism 17 and the bucket cylinder 21. The additional rod 37 is formed in a Y-shape with a proximal end branched into two branches. Further, the additional rod 37 has a proximal end portion disposed coaxially with the distal end portion of the rod 21B of the bucket cylinder 21, and a spacer 38 and one end of the second link 17B are disposed so as to sandwich the proximal end portion from both sides. Thus, the connecting pin 36 is inserted over these. The tip of the additional rod 37 is disposed coaxially with the other end of the first link 17A, and the spacer 38 and one end of the additional link 35 are disposed so as to sandwich the first link 17A from both sides. The connecting pin 36 is inserted. Thereby, the additional rod 37 can connect the bucket 15 and the bucket cylinder 21 which are separated by providing the wear-resistant top 32.

  The hydraulic excavator 1 applied to the first embodiment has the above-described configuration, and according to the work content, a standard working device 11 suitable for excavation work on a flat ground, a cliff, and the like, It can be changed to a muddy place where earth and sand or the like can wear due to intrusion into the sliding part, and a wear-resistant work device 31 suitable for work in water.

  First, the standard working device 11 has a bush 14B wider than the bucket connecting pin 16 by attaching the bucket 15 to the standard bearing device 14 provided at the tip of the arm 13 via the bucket connecting pin 16. The contact area can be slid and the impact transmitted from the bucket 15 can be received sufficiently. Thereby, the standard working device 11 can perform, for example, excavation work on a flat land, a cliff, or the like, or a demolition work of a building.

  On the other hand, when performing an operation in which earth and sand may invade the sliding portion and wear, a wear-resistant top 32 provided with a durable bearing device 34 having high durability against wear is attached to the tip side of the arm 13. At this time, the wear-resistant top 32 prepared in advance is attached to the distal end side of the arm 13 by using the connecting pin 36 instead of the bucket 15, and the bucket connecting pin 16 is attached to the durable bearing device 34 of the wear-resistant top 32. Attach the bucket 15 using, for example, In this way, the standard working device 11 can be changed to the wear resistant working device 31 with a simple work.

  As a result, the wear resistant work device 31 can efficiently prevent dirt, water, and the like from entering the sliding surface by the durable bearing device 34 having a double bush structure. Accordingly, since the durability of the outer bush 34B and the inner bush 34C can be improved, the wear-resistant work device 31 can be used even when performing muddy work, underwater work, etc., where wear due to intrusion of earth and sand is a concern. It can be used stably over a long period of time without causing excessive wear.

  According to the first embodiment configured as described above, for example, excavation work on level ground, cliffs and the like on which a load due to impact during excavation acts, leveling work, demolition work of a building, and the like are performed. In this case, without attaching the wear-resistant top 32 to the arm 13, the bucket connecting pin 16 is inserted into the bearing device 14 of the arm 13, and each bracket 15 </ b> C of the bucket 15 is attached. Thereby, the bucket 15 can be attached to the bearing device 14 of the standard specification suitable for the operation | work which a comparatively big load acts on the front end side of the arm 13. FIG.

  On the other hand, when performing muddy work, underwater work, etc., the wear-resistant top 32 provided with a durable bearing device 34 that has high durability against wear by preventing intrusion of earth and sand or water at the tip side of the arm 13 is provided. The bucket 15 can be attached in place of the bucket 15, and the bucket 15 can be attached to the durable bearing device 34 of the wear-resistant top 32 via the bucket connecting pin 16. As a result, the wear-resistant top 32 suitable for muddy work and underwater work can be attached to the distal end side of the arm 13, and the bucket 15 can be attached to the wear-resistant top 32.

  Therefore, in the first embodiment, a standard specification bearing device 14 capable of withstanding the load is obtained by a simple operation of attaching and removing the wear-resistant top 32 prepared in advance to the distal end side of the arm 13, and excellent wear resistance. Both the durable bearing device 34 can be obtained. As a result, it is not necessary to replace the arm 13, and it is not necessary to prepare two arms 13. Therefore, the workability when switching between the work devices 11 and 31 can be improved, and the cost burden on the customer is reduced. can do.

  Further, the wear-resistant top 32 can be attached using the connecting pin 36 by using the bearing device 14 and the link bearing device 13H that are provided in advance on the tip side of the existing arm 13. As a result, the wear-resistant top 32 can be easily attached to the arm 13 without any additional processing.

  Moreover, the wear-resistant top 32 has the same distance L1 between the first mounting hole 33A and the second mounting hole 33B and the distance L2 between the durable bearing device 34 and the first mounting hole 33A. Is set. As a result, the casing 33 of the wear-resistant top 32 can keep the protruding dimension from the tip of the arm 13 to the durable bearing device 34 short, and can shorten the overall length.

  As a result, when the wear-resistant top 32 is used, it is possible to prevent the entire length of the arm 13 including the wear-resistant top 32 from being inadvertently lengthened. Therefore, the work device 31 is formed to be lightweight and compact. As a result, assembly workability, portability, and the like can be improved. Moreover, the load which acts on the arm 13, the bucket cylinder 21, etc. can be reduced. Furthermore, the amount (angle) by which the bucket 15 rotates via the link mechanism 17 when the bucket cylinder 21 is expanded and contracted can be made substantially the same as when the bucket 15 is directly attached to the arm 13. And workability can be improved.

  In addition, the distance L1 between the first mounting hole 33A and the second mounting hole 33B of the casing 33 and the distance L2 between the durable bearing device 34 and the first mounting hole 33A are set to substantially the same dimension. Thus, the additional link 35 of the wear-resistant top 32 can have the same length and shape as the second link 17B used in the existing link mechanism 17. Thereby, since the additional link 35 and the second link 17B can be used as a common part, it is possible to prevent erroneous assembly and reduce costs.

  Further, the durable bearing device 34 used for muddy work, underwater work and the like can seal the sliding surfaces of the outer bush 34B and the inner bush 34C with the first seal member 34D and the second seal member 34E. . Thereby, it is possible to reliably prevent the sand and the like from entering the sliding surfaces of the outer bush 34B and the inner bush 34C over a long period of time, and to improve the durability of the durable bearing device 34 against wear. it can.

  Next, FIGS. 13 to 15 show a second embodiment of the present invention. The feature of the present embodiment is that a replacement top provided with a replacement bearing device on the tip side of an arm is attached instead of a work tool. It is in the configuration. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

  In FIG. 13, reference numeral 41 denotes an exchange top according to the second embodiment that is detachably attached to the distal end side of the arm 13. The replacement top 41 is replaced with the arm 13 in place of the bucket 15 when the bearing device 14 provided on the distal end side of the arm 13 is worn due to, for example, long-term use or is damaged due to unreasonable work, falling rocks, or the like. It is to be attached to the tip side. As shown in FIGS. 14 and 15, the replacement top 41 is roughly constituted by a casing 42 and a replacement bearing device 43 described later.

  Reference numeral 42 denotes a casing of the replacement top 41. The casing 41 is provided with a connecting pin 36 on the bearing device 14 which is located at a substantially intermediate portion in the length direction and is the first bearing device of the arm 13 in the same manner as the casing 33 according to the first embodiment described above. The first mounting hole 42A to be mounted using and the second mounting member 36H to be mounted on the link bearing device 13H, which is located on the base end side in the length direction and serves as the second bearing device of the arm 13, using the connecting pin 36. And mounting holes 42B.

  Reference numeral 43 denotes a replacement bearing device provided at the tip of the casing 42. The replacement bearing device 43 is configured to pivotally attach the bucket 15 to the distal end side of the arm 13, and is configured in substantially the same manner as the standard specification bearing device 14 according to the first embodiment.

  Here, the replacement top 41 is substantially the same as the wear-resistant top 32 according to the first embodiment, and the distance L1 between the first mounting hole 42A and the second mounting hole 42B of the casing 42 and the replacement bearing device. 43 and the first mounting hole 42A are set to have substantially the same distance L2 (L1≈L2).

  Thus, according to the second embodiment configured in this way, 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, when the bearing device 14 provided on the distal end side of the arm 13 is worn due to, for example, long-term use or is damaged due to excessive work, falling rocks, etc., Instead of the bucket 15, an exchange top 41 provided with an exchange bearing device 43 can be attached. Accordingly, a new replacement bearing device 43 can be obtained by a simple operation without performing a welding operation, an arm 13 replacement operation, or the like, and the operation is performed by attaching the bucket 15 to the replacement bearing device 43. Can do.

  In the first embodiment, the durable bearing device 34 includes a boss member 34A provided on the distal end side of the arm 13, an outer bush 34B fitted in the boss member 34A, and an outer peripheral side on the outer side. An inner bush 34C that is slidably fitted in the bush 34B and has an inner peripheral side fitted to the bucket connecting pin 16, and a first seal member 34D that seals between the inner bush 34C and the boss member 34A. In the above description, the double bush structure including the second seal member 34E that seals between the inner bush 34C and the bucket connecting pin 16 is described as an example.

  However, the present invention is not limited to this, and for example, a durable bearing device 51 according to a modification as shown in FIG. 16 may be used. In this case, the durable bearing device 51 includes a cylindrical boss member 51A, a bush 51B that is fitted in the boss member 51A, and the bucket connecting pin 16 is slidably inserted on the inner peripheral side, What is necessary is just to comprise by the sealing member 51C located in the both ends of the bush 51B, and being attached to the said boss member 51A 2 each. Even in this configuration, the sealing members 51C arranged in two stages can prevent intrusion of earth and sand and water, and can improve durability against wear. Further, a durable bearing device may be used in which a high-performance single-stage seal member is used or the structure of the boss member and bush is changed to prevent intrusion of earth and sand.

  On the other hand, in the first embodiment, the case where the additional rod 37 that connects the first link 17A of the link mechanism 17 and the rod 21B of the bucket cylinder 21 is formed in a Y shape with the proximal end branched into two branches. Explained with an example. However, the present invention is not limited to this. For example, a plate formed with two pin holes such as the additional link 35 is used as an additional rod, and the first link 17A of the link mechanism 17 and the bucket cylinder 21 are used. It is good also as a structure which connects the rod 21B of this. That is, the additional rod may adopt a shape other than the illustrated shape as long as it can connect the first link 17A of the link mechanism 17 and the rod 21B of the bucket cylinder 21. This configuration can be similarly applied to the second embodiment.

  Furthermore, in each embodiment, the case where the bucket 15 was attached as a working tool to the front end side of the working devices 11 and 31 was described as an example. However, the present invention is not limited to this. For example, a work tool such as a breaker, a fork grapple, or a crusher may be attached to the distal end side of the arm 13.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view showing a hydraulic excavator applied to a first embodiment of the present invention with a standard working device. It is a front view which expands and shows the arm in FIG. 1, a bucket, a link mechanism, and a bucket cylinder. It is the expanded sectional view which looked at the bearing apparatus and bucket connection pin of a standard specification from the arrow III-III direction in FIG. It is a front view which shows the hydraulic excavator applied to the 1st Embodiment of this invention in the state provided with the working apparatus of abrasion-proof specification. It is a front view which expands and shows the arm in FIG. 4, a bucket, a link mechanism, a bucket cylinder, and a wear-resistant top. It is operation | movement explanatory drawing which shows the state which attaches a wear-resistant top to the front end side of an arm. It is a top view which expands and shows the arm shown in FIG. 5, a link mechanism, a bucket cylinder, and a wear-resistant top. It is a front view which expands and shows a wear-resistant top. It is a top view which expands and shows a wear-resistant top. It is an expanded sectional view which looked at the durable type bearing apparatus and the bucket connection pin from the arrow XX direction in FIG. It is a disassembled front view shown in the state which decomposed | disassembled the arm, the bucket, the link mechanism, the bucket cylinder, and the abrasion-resistant top. FIG. 3 is an exploded plan view showing an arm, a bucket, a link mechanism, a bucket cylinder, a wear-resistant top and the like in an exploded state. It is operation | movement explanatory drawing which shows the state which attaches the exchange top applied to the 2nd Embodiment of this invention to the front end side of an arm. It is a front view which expands and shows an exchange top. It is a top view which expands and shows an exchange top. It is an expanded sectional view which shows the durable bearing apparatus by the modification of this invention with a bucket connection pin.

Explanation of symbols

1 Excavator (construction machine)
2 Lower traveling body (car body)
3 Upper swing body (car body)
DESCRIPTION OF SYMBOLS 11 Standard specification working device 12 Boom 13 Arm 13A Upper flange 13B Lower flange 13C Left web 13D Right web 13E Arm cylinder attachment part 13F Boom attachment part 13G Bucket cylinder bracket 13H Link bearing device 14 Standard specification bearing device 15 Bucket 15A Bottom plate 15B Side plate 15C Bracket 16 Bucket connection pin 17 Link mechanism 17A First link 17B Second link 17C, 36 Connection pin 18 Link connection pin 21 Bucket cylinder 31 Wear-resistant working device 32 Wear-resistant top 33, 42 Casing 33A, 42A First mounting hole 33B, 42B Second mounting hole 34, 51 Durable bearing device 34A Boss member 34B Outer bushing 34C Inner bushing 34D First seal member 34E Second seat L1 35 Additional link 37 Additional rod 41 Replacement top 43 Replacement bearing device L1 Spacing dimension between the first mounting hole and the second mounting hole of the casing L2 Spacing dimension between the bearing device and the first mounting hole of the casing

Claims (5)

A boom provided on a vehicle body of a construction machine so as to be able to move up and down, an arm provided rotatably on the tip side of the boom and provided with a bearing device for pin coupling on the tip side, and a bearing device on the tip side of the arm In the working device of the construction machine constituted by the work tool that is rotatably attached via
A wear-resistant top provided with a durable bearing device having higher durability against wear than the bearing device is prepared in advance so that it can be attached to the distal end side of the arm instead of the working tool,
A construction apparatus for a construction machine, wherein when the wear-resistant top is attached to the tip side of the arm, the work tool is attached to the wear-resistant top using the durable bearing device. On the distal end side of the arm, there is provided another bearing device for attaching a link mechanism for transmitting the work tool cylinder expansion and contraction operation to the work tool.
The wear resistant top is provided with a first mounting hole that is attached to the bearing device of the arm using a connecting pin and a second mounting hole that is attached to the other bearing device using a connecting pin. The construction machine working device according to claim 1.   The wear resistant top is formed by setting the distance between the first mounting hole and the second mounting hole and the distance between the durable bearing device and the first mounting hole to be substantially the same. 2. The construction machine working apparatus according to 2.   The wear-resistant top durable bearing device includes a boss member provided on a tip side of the wear-resistant top, an outer bush fitted in the boss member, and an outer peripheral side slidable in the outer bush. An inner bush fitted to the connecting pin on the inner peripheral side, a first seal member for sealing between the end of the inner bush and the end of the boss member, and an end of the inner bush; The construction machine working device according to claim 1, 2 or 3, wherein the working device is constructed as a double bush structure including a second seal member for sealing between the outer periphery of the connecting pins. A boom that is provided on the vehicle body of the construction machine so as to be able to move up and down, and a first bearing device and a second bearing device that are rotatably provided at the distal end side of the boom and that are coupled to the pin at the distal end side in the longitudinal direction An arm that is spaced apart from the arm, a work tool that is rotatably attached to the distal end side of the arm via a first bearing device, and a base end side that is attached to the arm for operating the work tool. A working tool cylinder extending in the vicinity of the working tool with the distal end side being a free end, and the working tool cylinder at the tip side of the working tool and the arm tip in order to transmit the telescopic operation of the working tool cylinder to the working tool. In the working device of the construction machine constituted by the link mechanism connected to the second bearing device of
Prepare in advance an exchange top that can be attached to the tip of the arm instead of the work tool,
The replacement top includes a casing attached to the distal end side of the arm, and a first attachment hole provided at a central position in the longitudinal direction of the casing and attached to the first bearing device of the arm using a connecting pin. A second mounting hole provided on the base end side in the longitudinal direction of the casing and attached to the second bearing device of the arm using a connecting pin, and a replacement bearing device provided on the front end side of the casing And consisting of
The construction machine working apparatus according to claim 1, wherein when the exchange top is attached to the distal end side of the arm, the work implement is attached to the exchange top using the exchange bearing device.

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