JP2007045372A - Crawler shock-absorbing device of construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crawler shock-absorbing device of a construction machine, which efficiently fills a grease cylinder with grease in a short period of time. <P>SOLUTION: In the crawler shock-absorbing device of the construction machine, an endless crawler 7 wound around an idler 4 and a sprocket 6 provided before and behind a side frame 3b are adjusted in tension by a grease filled in a grease cylinder 21a, and a shock applied to the crawler 7 is mitigated by an urging means 26 to urge the idler 4. A locking means 27 to prevent the rotation of the grease cylinder 21a is provided between a supporting part of the grease cylinder 21a and the side frame 3b. Since the grease cylinder 21a is not turned by the vibration or the like generated during the operation of the construction machine, the work of filling the grease cylinder 21a with grease from a grease filling port 23 and adjusting the tension in the crawler 7 is efficiently performed in a short period of time. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a crawler shock absorber for a construction machine such as a hydraulic excavator that travels in a crawler belt.

For construction machines such as hydraulic excavators that have been driven by conventional crawler belts, a crawler belt shock absorber that tensions the crawler belt and simultaneously reduces the impact on the crawler belt by urging the idler fitted with the crawler belt forward of the vehicle body. Is attached to the front part of the side frame (for example, Patent Document 1).
In the idler support structure for a construction machine described in Patent Document 1, a yoke is provided at the front part of the side frame provided on both sides of the track frame so as to be freely swingable back and forth, and the idler can be freely rotated on the yoke. It is supported.
A substantially circular recess is formed at the rear end of the yoke, and the tip of a rod protruding from one end of the grease cylinder is fitted into the recess via an annular joining member. A coil is provided at the tip of the connecting rod projecting from the other end of the rod and biases the idler in a direction in which the crawler belt is tensioned between the spacer and a flange provided on the grease cylinder. A spring is interposed.

Also, a nut is screwed on the tip of the connecting rod, and the spring receiver is locked so as not to come out of the connecting rod, and the cylindrical portion of the spring receiver is attached to a partition provided in the side frame. A grease injection port for injecting grease into the working chamber in the grease cylinder is provided at the rear end of the connecting rod while being fitted in the hole.
The grease injection port is formed by a grease nip bent in an approximately L shape, and is attached to the connecting rod tip surface so that the tip portion faces the outside of the side frame so that grease can be easily injected.
Japanese Patent Application Laid-Open No. 11-124067

In the crawler shock absorber of the conventional construction machine configured as described above, when the endless crawler belt fitted between the idler and the sprocket is not tensed with a predetermined tension, when the vehicle changes its direction, the idler Tracks may fall off from the sprocket.
For this reason, when the crawler belt tension decreases, a grease gun is connected to the grease injection port, and grease is injected into the working chamber in the grease cylinder, so that the spring force of the coil spring is adjusted and the crawler belt is always applied to the predetermined track. Adjustments are made to obtain tension.
However, like the idler support device for a construction machine described in Patent Document 1, the conventional crawler cushioning device has a circular recess and a mounting hole at the ends of rods and connecting rods protruding from both ends of a grease cylinder. is recieving.
For this reason, when mounting the crawler shock absorber on the side frame, even if the grease cylinder is mounted so that the tip of the grease inlet is directed to the outside of the side frame, the grease cylinder will rotate due to vibration during operation, etc. The tip of the grease injection port may face the inside of the side frame, resulting in a problem that grease cannot be injected from the grease injection port.

In such a case, conventionally, a grease injection port is rotated using a tool such as a wrench so that the grease injection port faces the outside of the side frame. However, this operation is complicated and time-consuming. There is a problem of lowering work efficiency.
Also, when the tension in the crawler belt is weakened or the grease in the grease cylinder is replaced with a new one, it is usually necessary to attach a tool to the grease inlet and loosen the grease inlet to discharge the grease in the grease cylinder. However, in the conventional crawler belt shock absorber, when the grease injection port is rotated by a tool, the grease cylinder rotates together, so that the grease injection port cannot be loosened.
For this reason, conventionally, a grease injection port is loosened with a sleeper or the like inserted between the nut screwed into the tip of the connecting rod and the side frame so that the grease cylinder does not rotate. There is a problem that work efficiency is poor because it takes a lot of time and effort.
The present invention has been made to remedy such a problem, and an object of the present invention is to provide a crawler cushioning device for a construction machine which can efficiently inject and discharge grease into a grease cylinder in a short time.

  The crawler belt shock absorber of the construction machine according to the present invention includes a traveling body that rotates by rotating an endless crawler belt mounted on an idler and a sprocket provided on the front and back of the side frame, and slides back and forth on the front portion of the side frame. A yoke that is freely provided and whose idler is rotatably supported, a grease cylinder that is interposed between the yoke and the side frame and that adjusts the tension of the crawler track by the grease injected into the working chamber from the grease injection port, and the yoke A crawler cushioning device for a construction machine having an urging means for urging the idler forward via the anti-rotation means for preventing rotation of the grease cylinder between the support portion of the grease cylinder and the side frame. It is provided.

With the above configuration, the grease cylinder does not rotate due to vibrations etc. that occur during the operation of the construction machine. Therefore, it takes a short time to adjust the tension of the crawler track by injecting grease into the working chamber of the grease cylinder from the grease injection port. This makes it possible to efficiently perform inspections and maintenance work before work.
Also, when loosening the grease inlet by applying a tool to the grease inlet to reduce the tension of the crawler belt or replacing the grease in the grease cylinder with a new one, the anti-rotation means receives the rotational reaction force and the connecting rod is To prevent co-rotation, the grease injection port can be loosened or tightened without using sleepers, etc., thereby reducing maintenance of the crawler belt tension or replacing grease. It will be possible to do it efficiently in a short time.

  The crawler belt shock absorber of the construction machine according to the present invention has a polygonal fitting portion formed on a spring receiving member that slidably supports the rotation preventing means on the rear end side of the connecting rod protruding rearward from the grease cylinder. And a polygonal mounting hole that is formed in the side frame and fits the fitting portion, and a grease injection port is provided on the rear end surface of the connecting rod so that the tip portion faces the outside of the side frame. It is a thing.

  According to the above configuration, since it can be carried out only by changing the shape of the spring receiving member for supporting the connecting rod and the mounting hole, the cost increase due to the provision of the rotation preventing means can be minimized.

  The crawler belt shock absorber of the construction machine according to the present invention includes a traveling body that rotates by rotating an endless crawler belt mounted on an idler and a sprocket provided on the front and back of the side frame, and slides back and forth on the front portion of the side frame A freely provided yoke on which an idler is rotatably supported, a front end of a working rod projecting from the front part is in contact with the rear surface of the yoke, and a rear end side of a connecting rod projecting from the rear part is a spring. A grease cylinder that is slidably supported by the side frame via the receiving member, and that adjusts the crawler belt tension by injecting grease into the working chamber from a grease injection port provided on the rear end surface of the connecting rod; By urging the idler to the front of the side frame through the yoke and provided on the outer periphery of the grease cylinder, the crawler belt is tensioned and at the same time the impact acting on the crawler belt is reduced. A crawler belt shock absorber for a construction machine having an urging means, which is formed in a polygonal fitting portion formed in a spring receiving member and a partition wall provided in a side frame, and fitting the fitting portion A non-rotating means for preventing rotation of the grease cylinder is formed by the polygonal mounting hole, and a grease injection port is attached to the rear end surface of the connecting rod so that the front end portion faces the outside of the side frame. .

With the above configuration, the grease cylinder does not rotate due to vibrations etc. that occur during the operation of the construction machine. Therefore, it takes a short time to adjust the tension of the crawler track by injecting grease into the working chamber of the grease cylinder from the grease injection port. In order to weaken the crawler belt tension or replace the grease in the grease cylinder with a new one, when the grease inlet is loosened by applying a tool to the grease inlet, the anti-rotation means receives the rotational reaction force. In order to prevent the connecting rods from co-rotating, maintenance work such as weakening the crawler belt tension or replacing the grease can be performed efficiently in a short time.
Further, since it can be carried out only by changing the shape of the spring receiving member for supporting the connecting rod and the mounting hole, the cost increase due to the provision of the rotation preventing means can be minimized.

  According to the crawler belt shock absorber of the construction machine of the present invention, since the grease cylinder does not rotate due to vibration or the like generated during the operation of the construction machine, the grease is injected into the working chamber of the grease cylinder from the grease injection port. Maintenance work, such as adjusting the tension, can be performed quickly and efficiently.

Embodiments of the present invention will be described in detail with reference to the drawings.
1 is a side view of a construction machine made of a hydraulic excavator, FIG. 2 is a partially cutaway plan view of a track frame, FIG. 3 is a partially cutaway side view of the track frame, and FIG. 4 is an enlarged view taken along line AA in FIG. FIG. 5 is a cross-sectional view, FIG. 5 is a perspective view of the crawler belt shock absorber in the vicinity of the rotation preventing means, and FIG. 6 is a perspective view of the crawler belt shock absorber.
A construction machine including a hydraulic excavator illustrated in FIG. 1 includes a traveling body 1 that is capable of traveling freely and a revolving body 2 that is rotatably disposed on the traveling body 1.
The traveling body 1 has a track frame 3 including a center frame 3a and a pair of side frames 3b provided on both sides of the center frame 3a. An idler 4 is provided at one end of each side frame 3b. A sprocket 6 that is movably supported and is rotationally driven by a traveling motor 5 made of a hydraulic motor is provided on the other end side.
An endless crawler belt 7 is provided between the idler 4 and the sprocket 6, and the crawler belt 7 is driven by the sprocket 6 so that the traveling body 1 can self-propel and the side frame 3b. A plurality of rolling wheels 8 are rotatably supported on the upper and lower portions.

The revolving structure 2 installed on the center frame 3a of the track frame 3 so as to be able to swivel has a bottom part constituted by a body frame 2a, and a work machine 11 is mounted at the center of the front part of the body frame 2a.
As shown in FIG. 1, the work machine 11 has a base end pivotally attached to the body frame 2 a and can be raised and lowered by a boom cylinder 13, and a base end side pivotally attached to the tip end of the boom 12, and an arm cylinder 14. Is constituted by an arm 15 that can be rotated by a pivot, and a bucket 17 that is pivotally attached to the tip of the arm 15 and that can be pivoted by a bucket cylinder 16.
A driver's cab 10 is installed on the left side of the work machine 11 at the front of the vehicle body frame 2a, and an engine room 18 is installed at the rear of the vehicle body frame 2a. A power engine (see FIG. (Not shown), the upper surface and both side surfaces of the engine compartment 18 are covered with an engine cover 18a, and have a substantially sealed structure, and a counterweight 19 is attached to the rear end of the vehicle body frame 2a. .

On the other hand, a guide rail 3c is provided horizontally in the front-rear direction at the front portion of the side frame 3b, and a bearing 20a of a yoke 20 that supports the idler 4 is slidably supported on the guide rail 3c.
As shown in FIG. 2, the yoke 20 has a bifurcated structure on the front end side, and is provided with block-shaped bearings 20 a at the front ends, and shafts that project from the center of the idler 4 on these bearings 20 a. The part 4a is rotatably supported.
On the rear side of the yoke 20, a crawler belt shock absorber main body 21 that tensions the crawler belt 7 by urging the idler 4 forward and at the same time reduces the impact applied to the crawler belt 7 is installed.
As shown in FIG. 4, the crawler belt main body 21 has a grease cylinder 21a that is open at both end faces, and the rear end side of the operating rod 21b is slidably inserted into the front end of the grease cylinder 21a. The front end side of the connecting rod 21c is fitted into the end portion.
A flange-shaped joining member 22 is fitted to the front end side of the operating rod 21b, and a tapered projecting portion 22a projecting from the front surface of the joining member 22 is formed in a recess 20b formed on the rear surface of the yoke 20. It is mated.

A large-diameter portion 21d that is substantially equal to the inner diameter of the grease cylinder 21a is formed on the front end side of the connecting rod 21c. The large-diameter portion 21d engages with the end plate 21e of the grease cylinder 21a from the inside. The connecting rod 21c is prevented from coming off from the cylinder 21a, and the inside of the grease cylinder 21a defined by the large diameter portion 21d and the rear end surface of the operating rod 21b is an operating chamber 21f for adjusting the tension of the crawler belt 7. .
A passage 21g is formed in the central portion of the connecting rod 21c in the axial direction, the front end side of the passage 21g is opened in the working chamber 21f, and the rear end side is opened on the other end surface of the connecting rod 21c. .
A grease injection port 23 made of a grease nipple is detachably screwed into the opening of the passage 21g opened in the rear end surface of the connecting rod 21c.
As shown in FIG. 5, the grease injection port 23 is bent in an approximately L shape so that the front end faces the outside of the side frame 3 b, and a reverse upper valve (not shown) is provided inside the grease injection port 23. By connecting a grease gun (not shown) to the tip of the grease, grease can be injected into the working chamber 21f via the passage 21g by the grease gun.

On the other hand, on the rear end side of the connecting rod 21c, a spring receiving member 24 is fitted so as to be slidable in the axial direction, and a cylindrical spring fitting portion 24b projects from the front side of the flange portion 24a. .
One end side of the urging means 26 made of a coil spring fitted to the outer peripheral portion of the grease cylinder 21a is fitted to the spring fitting portion 24b, and the other end side of the urging means 26 is the front end side of the grease cylinder 21a. It is in contact with a flange-shaped spring seat 21h protruding from the outer periphery.
On the rear surface side of the spring receiving member 24, a rotation preventing means 27 for supporting the connecting rod 21c and preventing the grease cylinder 21a from rotating is formed.
As shown in FIGS. 5 and 6, the anti-rotation means 27 has a polygonal shape, for example, a quadrangular fitting portion 27a projecting from the rear surface of the spring receiving member 24, and an attachment hole formed on the side frame 3b side. 27b, the end face of the nut 28 screwed into the tip of the connecting rod 21c is brought into contact with the end face of the fitting portion 27a, and the spring receiving member 24 is locked so as not to come out of the connecting rod 21c. ing.
As shown in FIG. 2, a partition wall 3f made of a plate material is welded to the side frame 3b at the rear of the crawler belt cushioning device main body 21 in a direction orthogonal to the traveling direction. A fitting hole 27b having a square hole shape slightly larger than the joint portion 27a is formed. By fitting the fitting portion 27a into the attachment hole 27b, the grease cylinder 21a is locked so as not to rotate, and at the same time, connected. The rear end of the crawler belt shock absorber main body 21 is supported by the partition wall 3f of the side frame 3b through the collar 21c.
In addition, 3g in FIG. 5 is a work hole opened in the side surface of the side frame 3b.

Next, the operation of the crawler belt shock absorber of the construction machine constructed as described above will be described.
In attaching the idler 4 to the front portion of the side frame 3b, first, the crawler shock absorber main body 21 is assembled in the state shown in FIG. At this time, the phases of the attachment hole 27b of the rotation preventing means 27 opened in the partition wall 3f of the side frame 3b and the fitting portion 27a protruding from the rear surface of the spring receiving member 24 are matched. In this state, the crawler shock absorber main body 21 is prevented from rotating with a jig (not shown) so that the crawler belt shock absorber main body 21 does not rotate.
Next, when the crawler shock absorber main body 21 is inserted into the side frame 3b in this state and the fitting portion 27a of the rotation preventing means 27 is fitted into the mounting hole 27b of the partition wall 3f as shown in FIG. The bearing 20a of the yoke 20 supporting the bearing 20 is fitted and inserted into the front end side of the guide rail 3c. In this state, the yoke 20 is slid rearward to the recess 20b formed on the rear end surface of the yoke 20, and to the tip of the operating rod 21b. By fitting the tapered projection 20a of the attached joining member 22, the crawler belt cushioning device main body 21 and the idler 4 are assembled to the front portion of the side frame 3b as shown in FIG.

Next, when the traveling motor 5, the sprocket 6, the wheel 8, etc. are assembled to the side frame 3b, the endless crawler belt 7 is fitted between the idler 4 and the sprocket 6, and then the tension of the crawler belt 7 is adjusted.
The tension of the crawler belt 7 is adjusted by connecting a grease gun inserted from the work hole 3g of the side frame 3b to the grease inlet 23 of the crawler shock absorber main body 21, and the crawler shock absorber main body 21 is attached to the side frame 3b. Since the crawler shock absorber main body 21 is assembled to the side frame 3b in advance so that the tip of the grease injection port 23 faces the outside of the side frame 3b, the grease cylinder 21a is adjusted without adjusting the direction of the grease injection port 23. Thus, the grease can be injected into the working chamber 21f, and the work of tensioning the crawler belt 7 can be performed efficiently in a short time.

On the other hand, when an impact force is applied to the crawler belt 7 from the front during operation of the construction machine, the urging means 26 made of a coil spring contracts to relieve the impact force. Therefore, the crawler belt 7 is less likely to be damaged by an excessive impact force. In addition, if it has been operating for a long time, the crawler belt 7 may be stretched or worn, and the tension of the crawler belt 7 may be reduced.
In such a case, the grease gun inserted from the work hole 3g is connected to the grease inlet 23 at the time of inspection and maintenance before work, and the grease is filled into the working chamber 21f of the grease cylinder 21a. An anti-rotation means 27 is provided between the spring receiving member 24 that supports the rear end side of the rear end and the partition wall 3f of the side frame 3b, and the grease cylinder 21a rotates due to vibrations or the like generated during operation of the construction machine. For this reason, the tip of the grease inlet 23 always faces the outside of the side frame 3b.
As a result, the operation of injecting grease by connecting a grease gun to the grease injection port 23 can be performed in a short time, so that the work efficiency at the time of inspection before maintenance and maintenance is improved.

When the tension of the crawler belt 7 is weakened or when the grease in the grease cylinder 21a is replaced with a new one, the grease inlet 23 is loosened with a tool and the grease in the working chamber 21f is discharged. When the grease injection port 23 is rotated by applying a tool, the rotation preventing means 27 is subjected to a rotational reaction force to prevent the connecting rod 21c from rotating together. Thus, maintenance work such as reducing the tension of the crawler belt 7 or replacing the grease can be performed efficiently in a short time.
In the above embodiment, the fitting portion 27a of the anti-rotation means 27 has a quadrangular shape. However, as long as it functions as the anti-rotation of the crawler belt shock absorber main body 21, even with a two-sided width, a triangular or pentagonal shape. Of course, it may be.

It is a side view which shows the construction machine which employ | adopted the crawler belt shock absorber which becomes embodiment of this invention. 1 is a partially cutaway plan view showing a track frame of a construction machine that employs a crawler belt shock absorber according to an embodiment of the present invention. 1 is a partially cutaway side view showing a track frame of a construction machine that employs a crawler belt shock absorber according to an embodiment of the present invention. It is sectional drawing which follows the AA line of FIG. It is a perspective view which shows the rotation stopping means vicinity of the crawler belt shock absorber of the construction machine which becomes embodiment of this invention. It is a perspective view which shows the crawler belt shock absorber of the construction machine which becomes embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Traveling body 3b Side frame 3f Bulkhead 4 Idler 6 Sprocket 7 Crawler belt 20 Yoke 21a Grease cylinder 21b Actuation rod 21c Connection rod 21f Actuation chamber 23 Grease injection port 24 Spring receiving member 26 Energizing means 27 Anti-rotation means 27a Fitting part 27b Attachment Hole

Claims (3)

  A traveling body that rotates by rotating an idler provided before and after the side frame and an endless crawler belt mounted on a sprocket, and a front body that is slidable forward and backward, and the idler rotates. A freely supported yoke, a grease cylinder that is interposed between the yoke and the side frame and that adjusts the tension of the crawler belt with grease injected into a working chamber from a grease injection port, and the idler via the yoke A crawler belt shock absorber for a construction machine, which is provided with a biasing means for biasing the front of the grease cylinder, wherein a rotation preventing means for preventing rotation of the grease cylinder is provided between a support portion of the grease cylinder and the side frame. A crawler shock absorber for a construction machine.   The anti-rotation means is formed on the side frame and a polygonal fitting portion formed on a spring receiving member that slidably supports the rear end side of the connecting rod protruding rearward from the grease cylinder, And a grease-injection port provided on the rear end surface of the connecting rod so that the front end portion faces the outside of the side frame. The crawler belt shock absorber for a construction machine according to 1. A traveling body that rotates by rotating an idler provided on the front and back of the side frame and an endless crawler belt mounted on the sprocket, and a front and rear slidably provided on the front portion of the side frame so that the idler is rotatable. The front end of the operating rod projecting from the yoke is in contact with the rear surface of the yoke, and the rear end side of the connecting rod projecting from the rear is slidable via a spring receiving member. A grease cylinder that adjusts the crawler belt tension by injecting grease into a working chamber from a grease injection port provided on a rear end surface of the connecting rod, and The crawler belt is tensioned and acts on the crawler belt by urging the idler forward of the side frame through the yoke. A crawler belt shock absorber for a construction machine provided with an urging means for mitigating an impact, wherein the crawler belt shock absorber is formed in a polygonal fitting portion formed in the spring receiving member and a partition wall provided in the side frame, and The polygonal mounting hole for fitting the fitting portion constitutes a rotation preventing means for preventing the rotation of the grease cylinder, and the tip end portion faces the outside of the side frame on the rear end surface of the connecting rod. A crawler shock absorber for a construction machine, wherein the grease injection port is attached to the crawler belt.

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