JP2002053033A - Running device for crawler type vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability of a running operation and to restrict load on a brake, in a crawler type vehicle having a seat switchable between a forward attitude and a backward attitude and running levers on both front and back sides of the seat. SOLUTION: Two sets of hydraulic remote control valves 14 and 15 corresponding to the front and back running levers 7 and 7 are disposed, and the corresponding valve is connected to a hydraulic pump control valve through a high pressure selector valve 13 for operation changeover. A pressure switch 42 for alarming for backing is provided in the downstream side of the high pressure selector valve 13. A supply oil passage 45 of a remote control valve and a parking brake releasing oil passage 38 to a parking brake releasing piston are disposed in parallel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crawler-type vehicle operating mechanism.

[0002]

2. Description of the Related Art In a crawler-type vehicle equipped with a seat that can be switched between a forward-facing and a rearward-facing posture and a running lever on both front and rear sides of the seat, the crawler is driven by a running lever connected to a front or rear mechanical link. Arrangements for operating an articulated vehicle are known. There is also known a configuration in which one of the traveling levers is locked by a mechanical mechanism so that the operation cannot be performed. An example is disclosed in Japanese Patent Publication No. Hei 4-9710.

[0003]

When the switching operation is performed by a link type mechanism, play may occur due to wear of a fulcrum pin or the like, and maintenance requires a great deal of labor. Further, since a link type mechanism is used, the structure is complicated, the adjustment requires labor, and the assembly requires time. In addition, the conventional parking brake has a mechanism independent of a traveling lever that moves forward and backward, and can be operated simultaneously, so that an excessive load is applied to the brake and abrasion of the brake plate may occur at an early stage.

[0004]

To solve the above-mentioned problems, the following means are taken. Claim 1
As described in the above, in a crawler-type vehicle equipped with a seat that can be switched between a forward facing position and a backward facing position and a traveling lever on both front and rear sides of the seat, two sets of hydraulic remote control valves corresponding to the front and rear traveling levers are provided. did.

According to a second aspect of the present invention, there is provided a hydraulic circuit connected to a hydraulic pump control valve for controlling a pump discharge amount from a valve opposed to the two hydraulic remote control valves via a high-pressure selection valve for operation switching. Configuration.

According to a third aspect of the present invention, a pressure switch for a reverse warning is provided downstream of the high-pressure selection valve connected to the reverse valve of the remote control valve.

According to a fourth aspect of the present invention, parking is performed on a parking brake release piston in parallel with a remote control valve supply oil passage from a shut-off valve operated by a parking brake lever to a remote control valve side, upstream of the two hydraulic remote control valves. A brake release oil passage was provided.

[0008]

Embodiments of the present invention will be described with reference to the accompanying drawings. 1 is an overall side view of a reverse type working vehicle, FIG. 2 is a front view thereof, FIG. 3 is a side view of a cabin, FIG. 4 is an assembly diagram showing a connection arrangement of a remote control valve of a travel lever, and FIG. FIG. 6 shows a configuration of a circuit, and FIG.
Is a diagram showing a configuration of a hydraulic oil supply circuit, FIG. 7 is a diagram showing a configuration of a remote control valve and a high pressure selection valve, FIG. 8 is an operation circuit diagram of a parking brake and a dump cylinder, FIG. 9 is a crawler drive circuit diagram, and FIG. It is a figure which shows the connection structure with the hydraulic circuit of an alarm.

Referring to FIGS. 1 and 2, the overall construction of a reverse work vehicle 1 which is an example of a crawler type irregular terrain vehicle will be described. The reverse-type work vehicle 1 includes a crawler-type traveling device 2, a main frame 3, and a dump-type carrier 4. A main frame 3 is mounted on the crawler type traveling device 2, and a dump type carrier 4 is disposed at a rear portion of the main frame 3. The dumping platform 4 is pivotally supported by a dump cylinder (not shown) so as to be able to move up and down. The dumping platform 4 is moved up and down by a dump cylinder to move earth and sand loaded on the dumping platform 4 into a reverse working vehicle 1. It is configured to discharge to the rear of the vehicle.

A cabin 5 is provided at the front of the body, and a seat 6 is provided inside the cabin 5. An engine 11 is provided beside the cabin 5, and the crawler traveling device 2 is driven by the driving force of the engine 11. The cabin 5 includes a roof portion that covers the seat 6 and a support portion that supports the roof portion. The front surface and the left and right side surfaces of the cabin 5 are open, and a fence is provided on the rear surface of the cabin 5, and the upper portion of the fence is open. With this configuration, the operator sits on the seat 6 and can visually recognize the front, left, right, and rear of the reverse work vehicle 1.

As shown in FIG. 3, a traveling lever 7 is disposed in front of and behind the seat 6, respectively. The traveling lever 7 is used to operate forward and backward and turn. The traveling lever 7 is connected to a hydraulic control valve (not shown), and is configured to operate the reverse type work vehicle 1 by operating the hydraulic control valve. The seat 6 is rotatably supported by a center box 8, and is normally fixed forward or backward by a lock mechanism (not shown). Further, even when the seat 6 faces rearward, the rear surface of the cabin 5 is open, so that the operator can visually observe the rear of the reverse work vehicle 1 while sitting on the seat 6 from the opening. Has become.

Next, the configuration of the traveling lever 7 will be described with reference to FIG. The base of the traveling lever 7 is a remote control valve 14
15 for controlling the remote control valves 14 and 15 by operating the travel lever 7. A high pressure selection valve 13 is connected to a lower portion of the remote control valve 14, and the remote control valve 15 is also connected to the high pressure selection valve 13 by piping. Remote control valve 14 is provided on the upper surface of high pressure selection valve 13.
And the remote control valve 15 disposed on the opposite side via the driver's seat 6 is connected to the high-pressure selection valve 13 by a hydraulic pipe, so that the operation mechanism can be easily configured. Lower part of remote control valves 14 and 15 and high pressure selection valve 1
Hydraulic ports are provided on the side surface of 3, and the hydraulic ports are connected to each other by hydraulic piping. Therefore, the configuration can be simplified, and the assemblability can be improved.

Next, a hydraulic circuit for driving the traveling device 2 will be described with reference to FIG. The hydraulic circuit shown in FIG. 5 includes a hydraulic oil supply circuit 12, a high pressure selection valve 13, a remote control valve 14,
15, shut-off valve 16, dump cylinder 17,
Dump cylinder operation circuit 18, crawler drive circuit 19
20. In the hydraulic oil supply circuit 12, a hydraulic pump is driven by the engine 11 to supply hydraulic oil to the hydraulic circuit. The engine 11 is connected to three hydraulic pumps, two of which are variable hydraulic pumps, which supply hydraulic oil to the hydraulic motors of the crawler drive circuits 10 and 20 by the variable hydraulic pumps. The remaining one hydraulic pump is for generating pilot hydraulic pressure.

The hydraulic cylinder supply circuit 12 includes a dump cylinder 1
7 is connected, and the dump cylinder 17 is expanded and contracted by hydraulic oil supplied from the hydraulic oil supply circuit 12. The operating circuit 18 is supplied with hydraulic oil from a constant displacement hydraulic pump of the hydraulic oil supply circuit 12, and controls a hydraulic oil supplied to the dump cylinder 17 by operating a lever provided in the operating circuit 18. Then, the expansion and contraction of the dump cylinder 17 is controlled.

The hydraulic oil supply circuit 12 has a remote control valve 14.
15 is connected via the high pressure selection valve 13. The remote control valves 14 and 15 control the discharge amount and the discharge direction of the hydraulic oil of the variable hydraulic pump disposed in the hydraulic oil supply circuit 12. The travel levers 7, 7 are connected to the remote control valves 14, 15, respectively, and the remote control valve 14 or the remote control valve 15 is operated by the travel lever 7.

The high pressure selection valve 13 is connected to the hydraulic oil supply circuit 12,
They are connected by four oil passages. These are a left crawler drive pump forward oil path 22, a left crawler drive pump reverse oil path 23, a right crawler drive pump forward oil path 24,
The right crawler drive pump reverse side oil passage 25. The remote control valves 14 and 15 are connected via the high pressure selection valve 13. The high-pressure selection valve 13 selects one of the remote control valves 14 and 15, and is disposed so that the one of the remote control valves can control the forward and backward movement of the left and right crawlers. While one of the remote control valves is being operated, the other remote control valve cannot be operated. For example, when the remote control valve 15 is operated, the oil passage connecting the remote control valve 14 and the hydraulic oil supply circuit 12 is closed by the high-pressure selection valve 13, and the operation to the remote control valve 15 is given priority. With such a configuration, when the traveling lever 7 disposed before and after the seat 6 is operated, only the operation of one traveling lever 7 is transmitted to the hydraulic oil supply circuit 12.

The hydraulic oil supply circuit 12 and the crawler circuit 19
A shut-off valve 16 is connected to 20 and the remote control valves 14 and 15. A parking brake is connected to the shut-off valve 16 in the crawler circuits 19 and 20, and slides by operating the parking brake to operate the parking brake provided in the crawler control circuits 19 and 20. Further, the supply of hydraulic oil to the remote control valves 14 and 15 is controlled by operating the shut-off valve 16. That is, a parking brake release oil passage is provided in parallel with the remote control hydraulic supply oil passage 21 to the remote control valves 14 and 15.

Next, the configuration of the hydraulic oil supply circuit 12 will be described in detail with reference to FIG. Hydraulic oil supply circuit 12
Are variable hydraulic pumps 31 and 32 and a hydraulic pump 33,
It is constituted by hydraulic control valves 34 and 35 and the like.
The variable hydraulic pumps 31 and 32 and the hydraulic pump 33 are driven by the engine 11 and have a hydraulic control valve 34.
The numeral 35 controls the movable swash plate of the variable hydraulic pumps 31 and 32. The hydraulic motor of the traveling device is driven by hydraulic oil discharged from the variable hydraulic pumps 31 and 32, and the hydraulic control valves 34 and 35 are controlled by the remote control valves 14 and 15.

Next, the configurations of the remote control valves 14 and 15 and the high-pressure selection valve 13 will be described with reference to FIG. The high pressure selection valve 13 is constituted by a plurality of high pressure priority type shuttle valves. The high pressure selection valve 13 is connected to the remote control valves 14 and 15, respectively. The remote control valve 14 is connected to the traveling lever 7 that is operated during forward movement, and the remote control valve 15 is connected to the traveling lever 7 that is operated during backward movement.
Connected to. By operating the travel lever 7, the corresponding relief valve of the remote control valve is controlled, and the hydraulic pumps 31 and 3 are controlled via the high-pressure selection valve 13.
2 is controlled.

Next, the structure of the shut-off valve 16 connected to the parking lever will be described with reference to FIG. The switching valve 37 is connected to the parking lever 36, and the switching valve 37 slides by operating the parking lever 36. When the parking brake 39 is turned on, the remote control pilot is turned off, and the parking brake release passage 3
The oil pressure of 8 also decreases. Then, the parking brake 39 is turned off.
When in the F state, the remote control valve supply oil passage 45 is closed,
The remote control pilot is turned on, and the hydraulic pressure in the parking brake release passage 38 increases.

When the parking brake 39 is turned on, the supply of hydraulic oil to the remote control valves 14 and 15 is stopped. As a result, the swash plate control of the variable hydraulic pumps 31 and 32 stops, the swash plate becomes neutral, and the supply of hydraulic oil to the hydraulic motor stops. Further, the hydraulic pressure in the parking brake release passage 38 decreases, and the parking brake 39 described later is applied. Conversely, when the parking brake 39 is turned off, the remote control valve supply oil passage 45 is opened and the remote control valve 14 is opened.
・ Hydraulic oil is supplied to 15 and variable hydraulic pumps 31 and 32
Can be controlled by the remote control valves 14 and 15. Then, the hydraulic pressure in the parking brake release passage 38 increases, and the parking brake 39 is released. That is, when the parking brake 39 is applied, the supply of the hydraulic oil to the hydraulic motor that drives the crawler is stopped, and the braking is applied by the parking brake connected to the hydraulic motor. Thus, it is possible to perform efficient braking without applying braking while driving the hydraulic motor.

Next, the crawler drive circuit will be described with reference to FIG. The crawler drive circuits 19 and 20 include a hydraulic motor 40 and a parking brake 39. A drive wheel 41 and a parking brake 39 are connected to the hydraulic motor 40. When hydraulic oil is supplied to the hydraulic motor 40, the hydraulic motor 40 is driven and the drive wheel 41 is driven. When the parking brake 39 is operated, the driving wheels 41 are braked.

The parking brake 39 releases the brake when the hydraulic pressure is applied, and applies the brake by the urging member when the hydraulic pressure is lost. The parking brake 39 includes a friction plate and a biasing member, and the friction plate is configured to be fixed to the body and to rotate together with the output shaft of the hydraulic motor. When there is no oil pressure applied to the parking brake 39, the friction members are pressed against each other by the urging member and braking is applied. When the oil pressure is applied, the urging member is pushed back and the contact of the friction plate is released. Things.

Next, the operation mechanism of the alarm will be described with reference to FIG. A battery 44 and pressure switches 42 are connected to the alarm 43. Then, when the pressure switch 42 is turned on, the alarm 43 is activated. The pressure switches 42 are connected to the left crawler drive pump reverse side oil passage 23 and the right crawler drive pump reverse side oil passage 25, respectively, and are turned ON when the oil pressure of the oil passage becomes equal to or higher than a certain value. It becomes. That is, the remote control valve 14 or the remote control valve 1
5, the left crawler drive pump reverse oil passage 23 or the right crawler drive pump reverse oil passage 25
When the hydraulic pressure of the pressure becomes equal to or more than a certain value, the pressure switch 42
Is turned on, and the alarm 43 is activated. The alarm 43 is activated when the left crawler or the right crawler is driven backward. The alarm 43
Can be configured such that the pressure switches 42 are connected in series, and are activated only when both pressure switches 42 are turned on, that is, only when the vehicle is moving backward.

[0025]

As described above, the present invention has the following advantages. As set forth in claim 1, in a crawler-type vehicle equipped with a seat capable of being switched between a forward facing position and a rearward facing position and traveling levers on both front and rear sides of the seat, two sets of hydraulic remote control valves corresponding to the front and rear traveling levers. Is arranged, the reliability of the traveling device is improved, and the operation mechanism of the traveling device can be simply configured.

According to a second aspect of the present invention, there is provided a hydraulic circuit connected to a hydraulic pump control valve for controlling a pump discharge amount from a valve opposed to the two hydraulic remote control valves via a high-pressure selection valve for operation switching. With this configuration, the reliability of the traveling device is improved, and the operation mechanism of the traveling device can be simply configured.

According to a third aspect of the present invention, a pressure switch for reverse warning is provided downstream of the high-pressure selection valve connected to the remote control valve reverse valve, so that the reliability of the traveling device is improved and traveling is improved. The operation mechanism of the device can be simply configured.

According to a fourth aspect of the present invention, the parking is performed on the parking brake release piston in parallel with the remote control valve supply oil passage from the shut-off valve operated by the parking brake lever to the remote control valve on the upstream side of the two hydraulic remote control valves. Since the brake release oil passage is provided, it is possible to extend the life of the brake and to improve the reliability of the traveling device.

[Brief description of the drawings]

FIG. 1 is an overall side view of a reverse working vehicle.

FIG. 2 is a front view of the same.

FIG. 3 is a side view of the cabin.

FIG. 4 is an assembly diagram showing a connection arrangement of a remote control valve of the traveling lever.

FIG. 5 is a diagram showing a configuration of a travel control hydraulic circuit.

FIG. 6 is a diagram showing a configuration of a hydraulic oil supply circuit.

FIG. 7 is a diagram showing a configuration of a remote control valve and a high-pressure selection valve.

FIG. 8 is an operation circuit diagram of a parking brake and a dump cylinder.

FIG. 9 is a crawler drive circuit diagram.

FIG. 10 is a diagram showing a connection configuration of an alarm device with a hydraulic circuit.

[Explanation of symbols]

 7 Travel lever 11 Engine 12 Hydraulic oil supply circuit 13 High pressure selection valve 14/15 Remote control valve 16 Shut-off valve 17 Dump cylinder 19/20 Crawler drive circuit

Claims (4)

[Claims] 1. A crawler-type vehicle equipped with a seat capable of being switched between a forward facing position and a rearward facing position, and traveling levers on both front and rear sides of the seat, provided with two sets of hydraulic remote control valves corresponding to the front and rear traveling levers. A traveling device for a crawler-type vehicle, comprising: 2. A hydraulic circuit connected to a hydraulic pump control valve for controlling a pump discharge amount from an opposing valve of two sets of hydraulic remote control valves via a high pressure selection valve for operation switching. Item 2. A traveling device for a crawler type vehicle according to item 1. 3. The traveling device for a crawler-type vehicle according to claim 2, wherein a pressure switch for reverse warning is provided downstream of the high-pressure selection valve connected to the remote control valve reverse valve. 4. A parking brake release oil path to a parking brake release piston is provided in parallel with a remote control valve supply oil path from a shut-off valve for operating a parking brake lever to a remote control valve side, upstream of the two sets of hydraulic remote control valves. The traveling device for a crawler-type vehicle according to claim 1, wherein: