JP2000198471A - Crawler travel device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To expand the expansion-contraction stroke of a crawler travel device. SOLUTION: Leg bodies 26 which are right and left inwardly projected, are provided in right and left crawler travel bodies 11, supporting frames 21 right and left movably holding the right and left leg bodies 26 in a state where the right and left leg bodies 26 are longitudinally overlapped, are provided in a travel frame 12, and auxiliary leg bodies 27 which face the leg bodies 26 on one side out of the right and left sides and which are adjacent to the leg bodies 26 on the other side, are provided. Then, extension bodies 33 for extending the overlapped parts T2 are provided at the tip parts of the right and left leg bodies 26, and openings 28 into which the extension parts 33 can be inserted when the lateral distance between the right and left crawler travel bodies 11 is contracted, are provided at the tip parts of the auxiliary leg bodies 27.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crawler traveling device used for a construction machine such as a backhoe or the like, and more particularly to a device in which the distance between left and right crawler traveling members can be freely increased or reduced.

[0002]

2. Description of the Related Art As a conventional crawler traveling device used for a backhoe, the one shown in FIG. 7 is known. The crawler traveling device 61 mainly includes a pair of left and right crawler traveling bodies 64 each formed by winding an endless crawler belt 63 made of rubber or the like around a track frame 62, and a traveling frame 65 that supports the crawler traveling bodies 64. , This traveling frame 6
5 is provided with a pair of front and rear support cylinders 66, and each of the left and right track frames 62 is provided with a pair of front and rear legs 67 projecting inward from the left and right. It is inserted in the support cylinder 66 so as to be able to move left and right, and the driving body 68 such as a hydraulic cylinder drives the left and right crawler traveling bodies 64 to expand and contract the left and right spaces.

Further, since the left and right legs 67 are superposed one on the other, a gap is formed between the left and right legs 67 and the support cylinder 66 on the base end side.
2 is provided with an auxiliary leg 69 adjacent to each leg 67 to fill the gap.

[0004]

In the above prior art, the running stability and the stability during excavation work are improved by increasing the left-right spacing of the crawler running body 64, and the left-right spacing of the crawler running body 64 is reduced. As a result, it is possible to improve the running performance in narrow alleys and the like. However, in the crawler traveling device having the above-described configuration, the left and right legs 67 overlap each other in the support tube 66 so as to mutually support each other. It is necessary to secure enough overlap margin T,
In order to secure the overlapping margin T, the left-right distance between the left and right crawler traveling bodies 64 cannot be greatly increased, and it has been impossible to sufficiently improve running stability and the like.

In order to solve the above-mentioned problem, even if the crawler enlarged width is widened while extending the length of the legs 67 to secure the overlap allowance T, the left and right crawler traveling bodies 6
When the left-right space of the crawler traveling body 4 is reduced, the left-right space between the crawler traveling bodies is sufficiently reduced because the movement of the leg 67 inward in the left-right direction is restricted by abutting the opposing auxiliary leg 69. And running performance in narrow alleys and the like is impaired. That is, in the conventional crawler traveling device, the enlargement / reduction stroke of the left and right crawler traveling bodies 64 cannot be set large, and it has been difficult to achieve both improvement in traveling stability and the like and improvement in traveling performance on a narrow road.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a crawler traveling device that enables a crawler traveling body to set a large expansion / contraction stroke so that both traveling stability and traveling on narrow roads can be improved.

[0007]

The present invention employs the following technical means to achieve the above object. That is, the crawler traveling device according to the present invention is a crawler traveling device including a pair of left and right crawler traveling members 11 on a traveling frame 12 so as to be able to freely expand and contract the left and right intervals. Legs 26 projecting from
Is provided on the traveling frame 12, and a support frame 21 is provided on the left and right crawler traveling body 11 so that the left and right legs 26 can be freely moved in a state where the left and right legs 26 are overlapped with each other. An auxiliary leg 27 which is opposed to the left and right direction and is adjacent to the other leg 26,
An extension body 33 extending the overlapping margin T2 at the tip of
And an opening 28 into which the extension body 33 can be inserted when the left-right distance between the left and right crawler traveling bodies 11 is reduced is provided at the distal end of the auxiliary leg body 27.

According to this, in the state where the left and right crawlers 11 are widened, the left and right widths are set large while the overlap T2 of the left and right legs 26 is sufficiently secured by the extension body 33. In the state where the left-right distance of the crawler traveling body 11 is reduced, the extension body 3
3 is inserted into the auxiliary leg 27 via the opening 28, interference between the extension 33 and the auxiliary leg 27 is avoided, and the lateral width when the crawler is contracted is reduced as compared with the case where the leg is simply extended. And it is possible to improve running performance on narrow roads.

Further, the extension body 33 of the crawler traveling apparatus according to the present invention is characterized in that a tip end portion facing the auxiliary leg 27 is tapered.
Accordingly, the extension body 33 can be reliably inserted into the auxiliary leg body 27 through the opening 28, and the extension body 33 can be reduced in weight, and the increase in the weight of the crawler traveling device 1 due to the provision of the extension body 33 can be suppressed. Further, it is preferable that the extension body 33 is formed by casting and fixed to the leg body 26, whereby the degree of freedom of the shape of the extension body 33 is increased, and the tapered shape or the like can be easily formed.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6 show a backhoe 2 using a crawler traveling device 1 according to the present invention. As shown in FIGS. 3 and 4, the backhoe 2 is provided on the crawler traveling device 1 so as to be rotatable around a vertical axis.
And a driving unit 6 including a driver's seat 4 and a control unit 5 is provided on the swivel base 3, and an excavating work machine 10 including a boom 7, an arm 8 and a bucket 9 is freely swingable at the front end of the swivel base 3. In preparation.

The crawler traveling device 1 is mainly composed of a pair of left and right crawler traveling bodies 11 and a traveling frame 12 for supporting the crawler traveling bodies 11. It is configured as a freely variable leg type. The backhoe 1 is of a so-called small rearward turning type, and the turning locus drawn by the rear end of the turntable 3 fits within the front-rear width of the crawler running body 11 and the reduced width of the left and right crawler running bodies 11, and the crawler width is reduced. Makes it easy to travel on narrow alleys, etc., and at a place where the crawler traveling device 1 can pass, without contact with the surroundings,
Can be turned. In addition, when the crawler width is increased, excavation work such as running and digging a side ditch can be performed in a more stable state.

The crawler traveling body 11 includes a driving wheel 13,
Track frame 1 including driven wheel 14 and rolling wheel 15
An endless elastic crawler belt 17 made of rubber or the like is wound around the outer periphery of 6, and is driven forward by the operation of a hydraulic motor 18. The traveling frame 12 is provided with a support portion for the revolving base 3 above the substrate 19, and a pair of front and rear support frames 21, each having a U-shaped cross section, having an open upper side, with the longitudinal direction facing left and right, on the back side of the substrate 19. The support tube 22 is fixed, and the back surface side of the substrate 19 and the inner surface of the support frame 21 constitute a rectangular support tube 22. A hydraulic cylinder 2 is provided at the front of the traveling frame 12.
3 is provided with a dozer device 24 that swings up and down.

As shown in FIGS. 1 and 2, on the inner surface of the track frame 16, a leg
A pair of front and rear members 6 are provided, and the leg body 26 is formed by a square pipe, and is inserted into the support cylinder 22 so as to be movable left and right. Further, the legs 26 corresponding to the left and right are inserted so as to overlap in the front and rear within the support cylinder 22, and mutually support the gaps between each leg 26 and the support cylinder 22 so as to fill each other. The play of the crawler traveling body 11 against the frame 12 is prevented.

An auxiliary leg 27 is provided on the track frame 16 adjacent to the base end of each leg 26. The auxiliary leg 27 is supported by the base end of each leg 26. The auxiliary leg 27 is inserted into the support tube 22 so as to be movable left and right so as to fill a gap with the tube 22.
The backlash of the base end is prevented. The auxiliary leg 27 is formed in a U-shape in cross section with an open portion adjacent to the leg 26, has an opening 28 at the left or right inner end, and has the tip of the left or right auxiliary leg 27 and the other end. The auxiliary leg 27 and the leg 26 abut against each other in a state where the tip of the leg 26 faces in the left-right direction and the distance between the left and right crawler traveling bodies 11 is reduced.

An expansion / contraction drive 30 composed of a hydraulic cylinder is provided along the left-right direction between the front and rear support cylinders 22. A cylinder tube of the drive 30 is fixed to the inner surface of one of the left and right track frames 16, and a cylinder rod is provided. Is fixed to the inner surface of the other track frame 16. Therefore, the left and right crawler traveling bodies 1 are actuated by the operation of the driving body 30.
The interval of 1 is adapted to perform a scaling operation. An engaging hole 31 formed in a long hole in the left-right direction is formed on the upper surface of each leg 26, and an engaging pin 32 inserted into the engaging hole 31 is provided on the substrate 19 so as to protrude downward. In addition, when the engagement pin 32 comes into contact with the end of the engagement hole 31, the left and right crawler traveling body 11 is restricted in the amount of lateral movement.

At the tip of each leg 26, the leg 26
An extension 33 is provided to extend the length of the opening 28. The extension 33 is formed into a block shape by casting, and has an upper and lower and front and rear width smaller than the upper and lower and front and rear widths of the opening 28. The ends (left and right outer ends) are inserted into the cylinder of the leg 26 and fixed by fasteners such as welding and bolts, and the tip side projects left and right outward from inside the cylinder of the leg 26 and overlaps the other side. Slidably in contact with the opposite side surface of the leg 26. Therefore, when the left-right distance between the left and right crawler traveling bodies 11 is widened, even if the overlap allowance T1 of the leg 26 itself is small, the extension 33 can provide a sufficient overlap allowance T2, and the mutual support of the legs 26 is ensured. This makes it possible to prevent rattling and the like, and to set the maximum width of the left and right crawler traveling bodies 11 larger.

Further, when the crawler traveling body 11 has a reduced horizontal distance, the auxiliary leg 27 is formed in a U-shaped cross section, so that the extension 33 is in contact with the opposite side surface of the other leg 26. The auxiliary leg 27 is inserted into the auxiliary leg 27 via the opening 28 while being held, and the leg 26 and the auxiliary leg 27 facing left and right face each other. Accordingly, the left-right distance between the crawler traveling bodies 11 can be reduced to the minimum at which the auxiliary legs 27 and the legs 26 come into contact with each other without interference between the extension 33 and the auxiliary legs 27. In addition, the enlargement / reduction stroke S can be set large in conjunction with the increase in the maximum width of the crawler traveling body 11 described above.

As described above, by increasing the expansion / contraction stroke of the crawler traveling body 11, when the crawler traveling body 11 is reduced, it is possible to travel on a narrower alley in a city or the like, and when it is enlarged, it is possible to travel more stably. Excavation workability such as gutter digging can be improved. The outer side surface of the extension body 33 is formed with a tapered surface 33a at the tip end side so that the extension body 33 can be securely inserted into the auxiliary leg 27 even if play occurs between the legs 26 that overlap each other. It can be inserted. Further, by forming the extension body 33 on the tapered surface 33a, the weight of the extension body 33 can be reduced, and the increase in the weight of the crawler traveling body 11 due to the provision of the extension body 33 can be suppressed.

The extension body 33 has a tapered surface 33b whose outer surface on the base end side is also tapered so as to reduce the weight and to increase the front and rear wall thickness at the left and right central portions. Is formed thick to improve the strength. Further, the extension body 33 may be formed integrally with the leg body 26 by extending the tip of the leg body 26. Also in this case, the upper and lower widths and the front and rear widths of the extended portion are set to the opening 2.
8 may be formed to be smaller than the top and bottom and front and rear widths so as to be insertable into the auxiliary leg 27 through the opening 28.

As shown in FIG. 3 and FIG.
Is mounted on the swivel 3 via the support 35,
The support base 35 is formed in a U-shape when viewed from the front, houses a battery 36 therein, and has a cover 38 on the front surface thereof, which is detachable by a fastener 37 such as a bolt. An operation lever 39 for operating a hydraulic cylinder constituting the expansion / contraction driving body 30 is provided below the driver's seat 4, thereby facilitating the operation of expanding / contracting the crawler traveling body 11 from the driver's seat 4. ing.

The operating lever 39 is disposed in the front-rear direction, and has an operating portion 39 having a grip 40 detachably provided at a front end.
an operating rod 39b extending downward from the rear end of the operating portion 39a, bending backward from the extended end, and further bending downward from the rear end;
b, and a lever shaft 39c whose base end is supported by the revolving base 3 so that the base end can freely swing up and down around the axis in the left-right direction. The operating portion 39a is disposed and penetrates a vertically long hole 41 formed in the cover 38 and protrudes forward of the support base 35.

The operating portion 39a is moved up and down along the long hole 41, so that the lever shaft 39 is moved through the operating rod 39b.
is rotated to operate the control valve of the hydraulic cylinder 30 via a link mechanism or the like. When the operation lever 39 is provided below the driver's seat 4, the operation lever 39 may be an obstacle when replacing the battery 36 in the support base 35, but in this embodiment, the grip 40 is operated. The cover 38 is removed from the lever 39 and the cover 38 is
From the front and open the front, and swinging forward with the operation lever 39 lowered allows the operation lever 39 to be in a retracted state, thereby easily replacing the battery 36 without obstructing the operation lever 39. Can be done.

As shown in FIGS. 4 and 5, the dozer device 24 comprises a pair of left and right arms 42 supported by the traveling frame 12 so as to be able to swing up and down. The left and right widths of the main blade 43 are set corresponding to the widths of the left and right crawler traveling bodies 11 in the contracted state. An extension blade 48 is detachably attached to both ends of the main blade 43 via fasteners 47 including bolts 45 and nuts 46. The total width of the blade to which the extension blade 48 is attached is enlarged. The width corresponds to the width of the left and right crawler traveling bodies 11 in the state.

The arm 42 is provided with a storage portion 49 for storing the extension blade 48 when not in use. The storage portion 49 is provided on a top surface of each of the left and right arms 42 with a pair of front and rear brackets projecting left and right inward. 50, and the bracket 50
A hole 50a through which the bolt 45 of the fastener 47 is inserted is formed, and the mounting plate 48a of the extension blade 48 is fixed to the bracket 50 via the fastener 47 with the extension blade 48 arranged inside the arm 42. It is configured to store by doing. Accordingly, even when soil is moved to the back surface side of the main blade 43 due to burying work or the like by the main blade 43, the soil is less likely to cover the extended blade 48 in the stored state. Further, since the extension blade 48 is fixed to the storage portion 49 by using the fastener 47 for attaching to the main blade 42, the fastener 47 can be prevented from being lost.

The present invention is not limited to the above embodiment, and can be appropriately changed in design. The excavator using the crawler traveling device of the present invention is not limited to the above-described small backward turning type, It can be applied to a standard type in which the turning locus at the rear end of the turntable protrudes from the crawler traveling device, a so-called ultra-small turning type in which an excavating device is arranged beside a driver's seat, and the like.

[0026]

As described in detail above, according to the present invention,
It is possible to increase the expansion / contraction stroke of the crawler traveling body, and it is possible to achieve both improvement in traveling performance of the narrow path when the crawler width is reduced and traveling stability when the crawler width is enlarged.

[Brief description of the drawings]

FIG. 1 is a plan view of a crawler traveling body according to an embodiment of the present invention, showing an enlarged state and a contracted state of left and right crawler traveling bodies.

FIG. 2 is a diagram showing an arrow AA in FIG. 1;

FIG. 3 is a side view of the backhoe.

FIG. 4 is a plan view of the backhoe.

FIG. 5 is a perspective view showing a dozer device.

FIG. 6 is a side view showing an expansion / contraction operation lever of the crawler traveling device.

FIG. 7 is a plan view of a crawler traveling device showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crawler running device 11 Crawler running body 12 Running frame 21 Support frame 26 Leg 27 Auxiliary leg 28 Opening

Claims (3)

[Claims] 1. A crawler traveling device comprising a pair of left and right crawler traveling bodies (11) provided on a traveling frame (12) so as to be able to expand and contract a left / right interval, wherein the left and right crawler traveling bodies (11) are provided with left and right inner sides. The running frame (12) is provided with a leg (26) projecting from
A support frame (21) is provided so that the left and right legs (26) can be freely moved in the left and right direction with the left and right legs (26) overlapped with each other. An auxiliary body (27) is provided opposite to the right and left direction and adjacent to the other leg (26), and an extension body (T) is provided at the tip of the left and right legs (26) to extend the overlap margin (T). 3
3), and an opening (28) through which the extension body (33) can be inserted when the left-right distance between the left and right crawler traveling bodies (11) is reduced is provided at the tip of the auxiliary leg body (27). A crawler traveling device. 2. The crawler traveling device according to claim 1, wherein the extension body (33) has a tapered tip end facing the auxiliary leg body (27). 3. The crawler running device according to claim 1, wherein the extension body (33) is formed by casting and fixed to the leg body (26).