JP2002339402A - Lower traveling body of construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively protect pipes connected between a center joint and a traveling hydraulic motor without installing a pipe cover on a side frame. SOLUTION: The pipes 29 and 30 from the center joint 31 are introduced into the center frame 21, and are derived in an overhang part 24 extended toward the installing bracket 26 side of a driving wheel 28 via an opening part 32 arranged in a peripheral body part 21a of the center frame 21. An elongate hole 33 lengthwise in the direction orthogonal to the axis of a side frame 22 is bored in a lower plate 24a of the overhang part 24, and a circular through hole 34 is bored in an upper face plate 22a of the side frame 22. The pipes 29 and 30 are introduced into the side frame 22 via these elongate hole 33 and through hole 34, and are extended in a closed space between a side plate 22c in the side frame 22 and a partition plate 36a. An end plate 37 is installed on the tip of the side frame 22, and the traveling hydraulic motor 27 is connected to this end plate 37 via a pipe deriving opening 37a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine such as a hydraulic excavator, in which an upper revolving unit is pivotably installed via a revolving device, and a lower part of a crawler traveling construction machine driven by a hydraulic motor. It relates to a traveling body.

[0002]

2. Description of the Related Art As a construction machine, for example, a hydraulic shovel has a configuration shown in FIG. That is, in the figure,
Reference numeral 1 denotes a lower traveling body, and an upper revolving superstructure 3 is installed on the lower traveling body 1 via a revolving device 2 so as to be pivotable.
The upper swing body 3 is provided with a driver's cab 4 for an operator to sit down and operate each part of the hydraulic shovel, and a front work machine 5 equipped with earth and sand excavation means.
Is attached. The undercarriage 1 has crawler-type traveling means having a crawler belt 6.
And the driven wheel 8. The driving wheels 7 and the driven wheels 8 are supported by a frame constituting the lower traveling unit 1.

[0003] As shown in FIG. 5, the structure of a frame constituting the undercarriage 1 is a track frame 10.
Are the center frame 11 and the left and right side frames 1
2 and 12. The driving wheel 7 and the driven wheel 8
Both ends of these side frames 12 are rotatably supported. A center drum 11a is provided on the upper surface of the center frame 11, and two overhangs 11b are provided on each of the left and right sides. A total of four overhangs 11b are provided. It is connected to the left and right side frames 12. Center drum 11a
The swivel device 2 is installed in.

As shown in FIG. 6, hydraulic motors 13 are mounted on the left and right driving wheels 7, respectively. Each of these hydraulic motors 13 has at least two high-pressure pipes 1
4, 14 are connected. The hydraulic motor 13 is generally connected with two drain pipes as needed. The supply of pressure oil to the hydraulic motor 13 is performed from a hydraulic pump (not shown) provided on the upper swing body 3 side. The other end of the pipe 14 connected to the hydraulic motor 13 must be routed inside the upper swing body 3. For this purpose, a center joint 15 is arranged at the center of rotation of the center drum 11a.
5 is connected to the other end of the pipe 14.

[0005] From the viewpoint of the stability of the hydraulic excavator during traveling, it is desirable that the width between the crawler tracks 6 and 6 provided on the left and right is wide. For this purpose, as shown in FIG. 7, the crawler belt 6 projects outward from the upper swing body 3. That is, the crawler belts 6 protrude from the left and right sides of the upper swing body 3 by the dimension P. Therefore, when the width dimension of the upper swing body 3 is B, the vehicle width dimension of the hydraulic shovel is B + 2P. The hydraulic excavator is loaded on a trailer and transported at the time of shipping or moving between work sites. Since there are places on the road where the vehicle width that can be passed is limited, it is desirable that the vehicle width can be reduced to about the width of the upper swing body 3 for transportation or the like. For this purpose, the center frame 1
The overhanging portion 11b and the side frame 12 are detachably connected to each other, and the connection position therebetween can be changed in a direction orthogonal to the axis of the side frame 12.

FIG. 8 shows a state in which the side frame 12 is extended outward, and FIG. 9 shows a state in which the side frame 12 is pulled inward. The projecting portion 11b of the center frame 11 is in contact with the upper surface of the side frame 12, and is fixed in a connected state by using a plurality of bolts 16 therebetween. Therefore, the distance between the hydraulic motor 13 and the center joint 15 changes between the extended state of the side frame 12 in FIG. 8 and the retracted state in FIG. 9, and the piping 14 connecting the hydraulic motor 13 and the center joint 15 has flexibility. When it is necessary to be composed of a hose and it is in the retracted state,
It is necessary to secure a space for absorbing the amount of flexure of No. 4.
The overhanging portion 11b of the center frame 11 has a box shape and accommodates a pipe 14 therein, and a considerably large space is secured even when a plurality of pipes 14 are accommodated. Therefore, this overhang 11
The internal space b is a space for absorbing the deflection of the pipe 14.

[0007] A through hole 17a is formed in the partition wall 17 constituting the overhang portion 11b of the center frame 11,
The pipe 14 is drawn out of the projecting portion 11b through the through hole 17a, extends along the side surface of the side frame 12, and the tip is connected to the hydraulic motor 13. Here, since the pipe 14 is formed of a flexible hose, a pipe cover 18 is provided in order to guard a portion of the pipe 14 that extends to the outside from the through hole 17a. It is provided fixed to the side surface of the frame 12. This protects the pipes 14 from being damaged by rocks or the like and damaging these pipes 14.

[0008]

The pipe cover 18 is provided only for protecting the pipe 14.
It is composed of a relatively thin steel plate. Then, a through hole 17a formed in the partition wall 17 forming the overhang portion 11b
As shown in FIG. 9, even when the side frame 12 is drawn inward, the side frame 12 must be located inside the side frame 12, so that the side frame 12 projects outward as shown in FIG. In this state, the through hole 17a is further displaced inward. Therefore, even in the state shown in FIG. 8, the pipe cover 18 attached to the side frame 12 projects largely from the side frame 12 to cover the pipe 14 drawn out from the through hole 17a. For this reason, rocks and the like repeatedly hit the pipe cover 18 while the vehicle is running or when excavating earth and sand, and the pipe cover 18 is deformed by the impact,
The function of guarding the piping 14 may be impaired due to damage. In order to prevent such a situation from occurring, the pipe cover 18 must have a large thickness and a high fixing strength to the side frame 12 in order to have a high strength. There is a problem that it becomes expensive and heavy, making it difficult to mount and attach to the side frame 12 for welding.

The present invention has been made in view of the above points, and an object of the present invention is to connect a center joint and a traveling hydraulic motor without mounting a pipe cover on a side frame. The purpose of the present invention is to make it possible to effectively protect pipes.

[0010]

In order to achieve the above-mentioned object, the present invention provides a center frame connected to an upper revolving unit via a turning device, and a pair of right and left connected to an overhang from the center frame. A track frame consisting of a side frame, a drive wheel connected to one end of the side frame, and a driven wheel connected to the other end, and a crawler belt between the drive wheel and the driven wheel. The drive wheel is provided with a hydraulic motor connected thereto, and a pipe from the hydraulic motor is extended to the upper revolving unit via the revolving device. A lower traveling body of a construction machine capable of adjusting an interval between frames, wherein the overhang portion is provided with a long hole that is elongated in a direction orthogonal to an axis of the side frame, and A through hole is provided in a position overlapping with the elongated hole on the upper surface of the id frame, and the pipe is connected to the hydraulic motor from inside the overhang portion through the inside of the side frame. It is assumed that.

[0011]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a cross section of a main part of a track frame constituting a lower traveling body of a construction machine,
2 shows a cross section taken along the line AA of FIG. 1, and FIG. 3 shows a cross section taken along the line BB of FIG.

1 and 2, reference numeral 20 denotes a track frame. The track frame 20 is composed of a center frame 21 and a side frame 22. A center drum 23 that supports the revolving body so as to be revolvable is provided. The center frame 21 has two projecting portions 24 extending to the left and right, respectively. And
Each of the overhang portions 24 is provided so as to be connected to the side frame 22. Here, the overhang portion 24 is connected to and fixed to the side frame 22 so as to be position-adjustable in a direction orthogonal to the axis of the side 22. This is similar to what was described in the prior art,
Widen the spacing between the left and right crawler tracks to ensure the stability of the body,
This is also to reduce the vehicle width during transportation. Therefore, each projecting portion 24 of the center frame 21 is detachably connected to the upper surface plate 22 a of the side frame 22 by the bolt 25.

At the end of the side frame 22, a mounting bracket 26 is connected and provided.
A traveling hydraulic motor 27 is mounted on 6, and the traveling hydraulic motor 27 is connected to driving wheels 28. Accordingly, when the hydraulic motor 27 is driven, the drive wheels 28 rotate, and a crawler belt (not shown) provided between the drive wheels 28 and the driven wheels is driven, and the vehicle travels. Will be. The traveling hydraulic motor 27 is connected to four high pressure pipes 29, 29 through which a pair of high pressure oils flow, and a pair of drain pipes 30, 30. The other ends of these pipes 29 and 30 are connected to a center joint 31 installed at the center of rotation of the center drum 23. Although not shown, the center joint 31 is connected to a pipe from a hydraulic pump installed on the upper swing body.

Pipes 29 and 3 from center joint 31
0 is guided inside the center frame 21. These pipes 29 and 30 are connected to the mounting bracket 2 of the drive wheel 28 through an opening 32 provided in the peripheral body 21 a of the center frame 21.
It is led out into the overhang portion 24 extending toward the sixth side. The lower plate 24a of the overhang portion 24 has a long hole 3 elongated in a direction orthogonal to the axis of the side frame 22.
3, and a circular through hole 34 is formed in the upper surface plate 22a of the side frame 22. And
The pipes 29 and 30 are introduced into the side frame 22 through the long holes 33 and the through holes 34. Here, the reason why the elongated hole 33 is provided in the overhang portion 24 is that the through hole 34 provided in the side frame 22 is also provided when the side frame 22 is pulled out or pulled into the overhang portion 24 of the center frame 21. This is for maintaining the state in which it communicates with the long hole 33 provided in the overhang portion 24.

As is apparent from FIG. 3, the side frame 22 includes an upper plate 22a, a lower plate 22b, and left and right side plates 2a.
2c and 22d. Here, the side plates 22c, 2
The interval between 2d is wider on the front end side than the contact portion of the drawer portion 24 than on the rear end side. Lower plate 22
The lower roller 35 is attached to b. Lower roller 35
Is composed of a roller 35a, and bearings 35b, 35b rotatably supporting a rotation shaft of the roller 35a.
The mounting portion of the roller 35a on the lower plate 22b is open. The left and right partition plates 36a and 36b are provided so as to sandwich the opening. Piping 2
Reference numerals 9 and 30 denote side plates 22c in the side frame 22.
And a partition plate 36a. An end plate 37 is attached to the end of the side frame 22. The end plate 37 has an opening 3 for leading out a pipe.
7a are formed. Accordingly, the pipes 29 and 30 are led out through the opening 37a and connected to the traveling hydraulic motor 27. Although not shown, the mounting bracket 26 may be provided with a motor cover that covers the traveling hydraulic motor 27. However, even if the motor cover is provided, the motor cover does not protrude inward from the position of the side plate 22c of the side frame 22.

In order to change the vehicle width, the side frame 22
Are displaced in a direction perpendicular to the axis of the vehicle, so that the traveling hydraulic motor 27 and the center joint 31
The pipes 29 and 30 connecting between the pipes are constituted by flexible hoses. Therefore, when rocks and the like collide with the pipes 29 and 30, they are easily broken. However, piping 2
Reference numerals 9 and 30 extend from the inside of the center frame 21, which is a structure having high strength constituting the track frame 20, and the overhanging portion 24 thereof to the inside of the side frame 22. Even if a rock or the like collides with the center frame 21, the overhang portion 24, and the side frame 22, the center frame 21, the overhang portion 24, and the side frame 22 are not deformed or damaged. Therefore, there is no possibility that the pipes 29 and 30 may be damaged.

In order to protect the pipes 29 and 30,
Since there is no need to provide a member such as a protective cover, the number of parts is reduced, and the assembling of the lower traveling body is facilitated. In addition, when the protective cover is provided, when the protective cover is damaged, it must be replaced, and the frequency of repair of the lower traveling body can be reduced by that much, thereby improving the maintainability.

[0018]

Since the present invention is constructed as described above, it is possible to effectively protect the pipe connected between the center joint and the traveling hydraulic motor without mounting the pipe cover on the side frame. Play.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a track frame showing one embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along the line BB of FIG. 1;

FIG. 4 is a front view of a hydraulic shovel as an example of a construction machine.

FIG. 5 is an exploded perspective view of a conventional track frame.

FIG. 6 is an external perspective view showing a connection structure of a pipe from a center joint to a traveling hydraulic motor.

FIG. 7 is a left side view of FIG. 4 omitting a front working machine.

FIG. 8 is a cross-sectional view of a main part of a conventional track frame.

FIG. 9 is a cross-sectional view similar to FIG. 8, showing a state where the side frame is retracted.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 20 Track frame 21 Center frame 22 Side frame 24 Projection part 26 Mounting bracket 27 Hydraulic motor 29, 30 Piping 31 Center joint 33 Long hole 34 Through hole 36a, 36b Partition plate 37 End plate 37a Opening

Claims (1)

[Claims] 1. A track frame comprising a center frame connected to an upper revolving structure via a turning device, and a pair of left and right side frames connected to a projecting portion from the center frame. A drive wheel is connected to one end side, and a driven wheel is connected to the other end side, and a crawler belt is wound and provided between the drive wheel and the driven wheel. A hydraulic motor is connected to the drive wheel. In the lower traveling body of the construction machine, the piping from the hydraulic motor is extended to the upper revolving body via the revolving device, and furthermore, the distance between the two side frames is adjustable. The overhang portion is provided with a long hole that is elongated in a direction perpendicular to the axis of the side frame, and a through hole is provided at a position overlapping the long hole on the upper surface of the side frame. Provided set, the pipe includes a lower traveling body of a construction machine, characterized in that through the interior of the side frame from the said projecting portion is configured to be connected to the hydraulic motor.