JPH08134955A - Control valve operation structure of back hoe - Google Patents

Abstract

PURPOSE: To connect control valve for work with an operation pedal by a simple structure in a back hoe and arrange both of them in a compact manner without creating waste space. CONSTITUTION: An operation pedal 34 which can perform oscillation operation freely is arranged around an oblique shaft core P2 at a position which is in front of a driver's seat 35 and is more to a side from a center A on the right and left of the driver's seat 35. A control valve unit 36 is arranged substantially in parallel with the shaft core P2 on the driver's seat 35 side from the operation pedal 34. A spool 27a which slides in the substantially orthogonal direction to the shaft core P2 is connected to the operation pedal 34 mechanically by a link mechanism 37 in a control valve 27 for work in the control valve unit 36.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arrangement of a work operation pedal provided on a swivel of a backhoe, and a structure for linking the operation pedal and a control valve.

[0002]

2. Description of the Related Art An example of a backhoe provided with an operation pedal as described above is disclosed in Japanese Utility Model Laid-Open No. 4-73056. In this backhoe, an axial center parallel to the front-back direction of the driver's seat (first part of the above publication)
An operation pedal (10 in FIGS. 1 and 3 of the publication) is arranged around 16) in FIGS. Then, the control valve unit (U in FIGS. 1 and 3 of the publication) is arranged in parallel with the left-right direction of the driver's seat, and the control valve of the control valve unit (V in the publication of FIG. 1) is arranged.
1) and the operation pedal are mechanically interlocked and connected.

[0003]

When the operator sits on the driver's seat in the above-mentioned backhoe, the operator often sits with his / her legs slightly open to the left and right. As a result, when the operation pedal is arranged so as to be swingable around the axis parallel to the front-rear direction of the driver's seat as described above, the worker sitting in the driver's seat puts his / her foot slightly inside (the left / right center side of the driver's seat). Since the operation pedal is operated toward the front, it may be difficult to operate the operation pedal.

In the above-mentioned backhoe, the axis about which the operation pedal is oscillated (the front-rear direction of the driver's seat) and the direction in which the control valve unit is arranged (the left-right direction of the driver's seat) are orthogonal to each other (the above-mentioned). (See FIG. 1 of the publication). As a result, the lateral movement of the operation pedal is converted into the longitudinal movement by the bell crank (20 in FIG. 1 of the publication) or the like, and the spool of the control valve (22 in FIG. 1 of the publication). Therefore, there is room for improvement in terms of simplification of the linkage structure between the operation pedal and the spool of the control valve. It is an object of the present invention to configure a backhoe control valve operating structure such that a linking structure between the operating pedal and the spool of the control valve is simple so that the operation pedal can be easily depressed.

[0005]

The feature of the present invention resides in that the backhoe control valve operating structure as described above is configured as follows. In other words, in the front of the driver's seat provided on the swivel seat, on the part of the swivel closer to the side from the left-right center of the driver's seat, the diagonal axis that moves farther from the driver's seat to the lateral A control pedal unit for oscillating operation is arranged around the core, and a control valve unit for driving the backhoe device is installed from the control pedal to the swivel base on the driver's side.
In the control valve for working in the control valve unit, the spool and the operation pedal that are slid in a direction substantially orthogonal to the axis of the operation pedal are arranged substantially parallel to the axis of the operation pedal by a link mechanism. Are linked together.

[0006]

With the construction of the present invention, as shown in FIG. 1, for example, the operation pedal 34 is obliquely arranged so as to open outward with respect to the driver's seat 35. As a result, when the worker sits on the driver's seat 35 with his / her legs slightly open to the left / right, the operator's seat does not have to turn his / her feet slightly inward (the left / right center A side of the driver's seat 35). Since the foot can be placed on the operation pedal 34 in a natural state when seated on the 35, the operation pedal 34 can be depressed in this natural state.

For example, as shown in FIG. 1, the operation pedal 34
When the control valve unit 36 is arranged substantially parallel to the axis P2 of the control pedal 34, the operation pedal 34 when the operation pedal 34 is depressed is operated.
And the spool 27a of the working control valve 27 in the control valve unit 36.
Is almost parallel to the slide direction. Thus, when the operation pedal 34 is depressed around the axis P2, the operation of the operation pedal 34 does not change its direction, and the link mechanism 3 is operated.
7 is transmitted to the spool 27a of the control valve 27, and the spool 27a is slid in the operating direction of the operation pedal 34 (direction substantially orthogonal to the axis P2).

In the present invention, for example, as shown in FIG. 1, when the control valve unit 36 is obliquely arranged with respect to the driver's seat 35 (substantially parallel to the axis P2 of the operation pedal 34), the control valve unit 36 is operated. It is arranged on the driver's seat 35 side with respect to the pedal 34. As a result, in a plan view, the operation pedal 34 and the control valve unit 36 are arranged so as to be laterally distributed within the driver's seat 35 and the front side of the driver's seat 35. The operating pedal 34 and the control valve unit 36 are compactly arranged without wasting space in a narrow range.

[0009]

As described above, in the control valve operating structure of the backhoe, the operator can step on the operation pedal in a natural state without turning the foot inward, and the operability of the backhoe can be improved. did it. When you depress the operation pedal, you can directly transfer the operation of the operation pedal to the spool of the control valve without changing the direction.
A structure for changing the direction of the operation pedal is not necessary, and a structure for linking the operation pedal and the control valve can be simply configured, which is advantageous in terms of simplification of the structure. Further, since the operation pedal and the control valve unit can be compactly arranged without wasting space in the driver's seat and a narrow area in front of the driver's seat, it is advantageous in using the space on the swivel base.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows the entire side surface of the backhoe, in which a swivel base 2 is supported by a traveling device 1 of a rubber crawler type, and a backhoe device 3 is provided in front of the swivel base 2. The backhoe device 3 is provided with a boom 4 which is rocked up and down by a hydraulic cylinder 11, an arm 5 which is rocked back and forth by a hydraulic cylinder 12, and a bucket 6 which is rocked back and forth by a hydraulic cylinder 13. It is configured.
A swing bracket 31 that supports the entire backhoe device 3 is swingably supported by a hydraulic cylinder 7 around a vertical axis P1 in the front portion of the swivel base 2.

Next, the hydraulic circuit structure of the backhoe will be described. As shown in FIG. 2, the first pump 8 is provided with a control valve 26 for the hydraulic motor 14 of the right traveling device 1, and a boom 4.
The control valve 21 for the hydraulic cylinder 11 and the control valve 23 for the hydraulic cylinder 13 of the bucket 6 are connected in parallel. The hydraulic motor 1 of the left traveling device 1 is attached to the second pump 15.
6, the control valve 28 for the hydraulic cylinder 11, the auxiliary control valve 25 for the hydraulic cylinder 11 of the boom 4, the control valve 22 for the hydraulic cylinder 12 of the arm 5, and the control valve 29 for the service port (not shown) are arranged in parallel. It is connected to the. The control valve 24 for the hydraulic motor 18 of the swivel base 2 in the third pump 17, and the control valve 3 for the hydraulic cylinder 19 that drives the dozer 32 shown in FIG.
3, and a control valve 27 for the hydraulic cylinder 7 that swings the swing bracket 31 is connected in parallel.

The control valves 21 to 29, 33 are of the center bypass type, and the control valves 26, 28 for the traveling device 1, the control valve 29 for the service port, and the control valve 33 for the dozer 32 are the operating levers (see FIG. It is a mechanically operated and neutral return type operated by (not shown). The control valve 27 for the swing bracket 31 is a mechanically operated neutral return type operated by an operation pedal 34 described later. The control valves 21 and 25 for the boom 4, the control valve 22 for the arm 5, the control valve 23 for the bucket 6, and the control valve 24 for the swivel base 2 are pilot operated by hydraulic pressure and are of a neutral return type.

Next, the control valve 21 for the backhoe device 3,
The operation structure of the control valve 24 for 22, 23, 25 and the swivel base 2 will be described. As shown in FIG. 1 and FIG. 3, a driver 20 is formed on the front side of the swivel 2 at a position closer to the left side from the left-right center of the swivel 2, and the left and right sides of a driver's seat 35 installed in the driver 20 are formed. On both sides, a right operation lever 9 and a left operation lever 10 that can be operated in the front, rear, left and right are provided. A pilot valve (not shown) that generates pilot pressure by operating the right and left operating levers 9 and 10 forward and backward and left and right is provided, and as shown in FIG. 2, the pilot valve supplies pilot pressure to the pilot valve. A pump 30 is provided.

Thus, when the right operation lever 9 is operated back and forth, the pilot pressure from the pilot valve operates the control valves 21 and 25 to swing the boom 4 up and down. (It works only when driving up)
When the right operation lever 9 is operated to the left or right, the control valve 23 is operated by the pilot pressure from the pilot valve and the bucket 6 is rocked back and forth. When the left operation lever 10 is operated back and forth, the pilot pressure from the pilot valve operates the control valve 22 to swing the arm 5 back and forth,
When the left operation lever 10 is operated to the left or right, the control valve 24 is operated by the pilot pressure from the pilot valve, and the swivel base 2 is driven to the right and left swivel sides.

As shown in FIG. 2, the hydraulic motors 14 and 16 for the traveling apparatus 1 are of variable output type. The hydraulic motors 14 and 16 are operated by a hydraulic cylinder 38 to shift between high and low stages. Hydraulic cylinder 38 on pilot pump 30
A switching valve 39 for the hydraulic motor 1 is connected to the hydraulic motor 1 by operating the switching valve 39 to expand and contract the hydraulic cylinder 38.
The gears 4 and 16 are shifted to the high and low stages.

Next, the operation structure of the control valve 27 for the hydraulic cylinder 7 of the swing bracket 31 will be described. As shown in FIGS. 1 and 3, the driver's seat 3 is located in front of the driver's seat 35.
In the part of the floor of the swivel base 2 which is located on the right side from the left-right center A of the vehicle 5, the driver's seat 3 is located farther away from the driver's seat 35.
An oblique horizontal axis P2 that moves away from the left-right center A of 5 to the right horizontal side
An operation pedal 34 is supported around (corresponding to an axis) so as to be swingable right and left.

Control valves 21 to 25 for the backhoe device 3,
The control valves 26 and 28 for the traveling device 1, the control valve 29 for the service port, the control valve 33 for the dozer 32, and the control valve 27 for the swing bracket 31 are arranged in a line to form one control valve unit 36. Each control valve 21
The spools 29 to 33 are arranged in parallel. From the operation pedal 34 to the left side of the drawing in FIG.
The control valve unit 36 is disposed below the driver's seat 35 so that the control valve unit 36 is substantially parallel to the horizontal axis P2 of the operation pedal 34 in the underfloor portion of the swivel base 2). The control valve 27 for the swing bracket 31 is provided at the front end of the control valve unit 36.
Is arranged, and the operation pedal 34 and the spool 27a of the control valve 27 are mechanically interlocked by a link mechanism 37.

With the above structure, when the operation pedal 34 is stepped left and right around the horizontal axis P2, the operation pedal 34 is operated.
Is transmitted to the spool 27a of the control valve 27 by the link mechanism 37 without changing the direction,
7a is slid in the direction substantially orthogonal to the horizontal axis P2 of the operation pedal 34 (the operating direction of the operation pedal 34), and the swing bracket 3 is moved by the hydraulic cylinder 7.
1 is swingably driven left and right.

[Other Embodiments] In the above embodiment, the operation pedal 34 and the control valve 27 for the swing bracket 31 are interlockedly connected, but the operation pedal 34 is controlled for the control valve 29 for the service port and the dozer 32. It may be interlocked with various control valves such as the valve 33. The operation pedal 34 is not the control valve 27 at the front end of the control valve unit 36, but the control valve unit 3
It may be interlocked with a control valve arranged in the middle of 6.

FIG. 1 shows a case where the present invention is applied to a swivel base 2 having a square shape in a plan view, but as shown in FIG. The present invention can also be applied to a backhoe in which the driver's seat 35 is arranged on the side. In the case of the circular swivel base 2, when the control valve unit 36 is obliquely arranged with respect to the driver's seat 35, the control valve unit 36 is arranged along the outer peripheral portion of the circular swivel base 2. Therefore, when the present invention is applied to the circular swivel base 2, it is advantageous in that the control valve unit 36 is arranged without wasting space. In the case of a backhoe provided with the swivel base 2 having a square shape and a circular shape in a plan view, particularly in the case of a small backhoe, the driver's seat 35 may be arranged in the left and right center of the swivel base 2, and the present invention is applied to such a backhoe. You may.

[0021] In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of drawings]

FIG. 1 is a plan view of the vicinity of a swivel base and a driving section.

FIG. 2 is a hydraulic circuit diagram for a backhoe device and a traveling device.

[FIG. 3] Overall side view of the backhoe

FIG. 4 is a plan view of the vicinity of a swivel base and a driving section in another embodiment.

[Explanation of symbols]

 2 swivel base 3 backhoe device 27 control valve 27a control valve spool 34 operation pedal 35 driver's seat 36 control valve unit 37 link mechanism P2 axis center A left and right center of driver's seat

Claims (1)

[Claims] 1. A driver's seat (3) provided on a swivel base (2).
5) In front of the driver's seat (35), the driver's seat (3)
5) The operation pedal (34) which can be rocked is arranged around an oblique axis (P2) which is further away from the left-right center (A) of the driver's seat (35) toward the side as it is further away from the front. A control valve unit (36) for driving the backhoe device (3) is provided at a portion of the swivel base (2) on the driver seat (35) side from the pedal (34) and a shaft center (P2) of the operation pedal (34). ), And in the working control valve (27) of the control valve unit (36), the axis (P) of the operation pedal (34) is arranged.
2) A control valve operating structure for a backhoe in which a spool (27a) that is slid in a direction substantially orthogonal to 2) and the operating pedal (34) are mechanically linked by a link mechanism (37).