JP2001354044A - Differential lock device for self-advancing type roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a roller from stopping not to travel, caused by a reason why all the fluid delivered from a pump flows to a motor on the slip side and why a driving wheel on the opposite side opposed to the slip side loses driving force, when a driving wheel attached to one side motor is slipped, in the case where two left and right hydraulic motors arranged in parallel to he one hydraulic pump are connected to the driving wheels of front or rear wheels to be used. SOLUTION: In a driving gear using the two left and right hydraulic motors 8a, 8b arranged in parallel with respect to the one hydraulic pump 1 to be connected via pipelines a1, a2, a differential lock mechanism provided with flow dividing valves 6a, 6b is provided on the respective left and right hydraulic pipelines a1, a2, advancing and retreating of the roller are detected, the flow dividing valves 6a, 6b are made to be interposed only in this side of the hydraulic motors 8a, 8b for driving in any case of the advancing or the retreating, and the hydraulic fluid is replenished from an auxiliary pump 2 even when the roller is not under a rectilinear condition, so as to escape from a travel- incapable condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential lock device for a self-propelled rolling machine.

[0002]

2. Description of the Related Art Conventionally, as a differential lock mechanism of a rolling machine, a structure as shown in FIG. 3 or FIG. 4 has been used. FIG. 5 is a hydraulic circuit diagram of a general self-propelled rolling machine.
In FIG. 5, 1 is a hydraulic pump driven by the engine 10, and 2 is an auxiliary pump. The oil generated by the hydraulic pump 1 is
The hydraulic pumps are connected to the hydraulic motors 8a and 8b via a line 1 and from the hydraulic motors 8a and 8b to the hydraulic pump 1 via a line a2. Reference numerals 9a and 9b denote braking devices incorporated in the hydraulic motors 8a and 8b, respectively, which are connected from the auxiliary pump 2 via the electromagnetic switching valve 3 and the pipeline b. 11 is an oil tank.

FIG. 3 shows a hydraulic circuit of a differential lock device using brake devices 9a and 9b built in hydraulic motors 8a and 8b in the hydraulic circuit of FIG. In FIG. 3, reference numeral 12 denotes a solenoid switching valve for selecting which of the left and right braking devices 9a and 9b is to be operated. In the position shown in FIG. Hydraulic motor 8
A braking force acts on b. At the position B of the switching valve 12, a braking force acts on the hydraulic motor 8a. 13 is a check valve for adjusting the braking force, and 14 is a throttle valve.

FIG. 4 is another hydraulic circuit diagram of a differential lock device using a flow dividing valve in the hydraulic circuit of FIG.
In FIG. 4, reference numerals 4a and 4b denote solenoid switching valves for turning on and off the differential lock device during forward movement.

[0005] In the case of FIG. 3, the driving wheels on the slipping side are braked, and the oil flows to the driving wheels on the side opposite to the slipping side so as to escape the state in which the vehicle cannot travel. is there. On the other hand, in the case of FIG. 4, when the vehicle becomes incapable of traveling, the flow dividing valve 6a is mainly connected between the hydraulic pump 1 on the forward side (in some cases, the reverse side) and the two left and right driving hydraulic motors 8a and 8b. It is interposed. Due to the presence of the flow dividing valve 6a, oil is forcibly flown to the hydraulic motors 8a and 8b on both sides to escape from the traveling impossible state.

In the case of FIG. 3, it is necessary for the operator to determine which of the left and right driving wheels is slipping, switch a switch (not shown) to switch the solenoid switching valve 12, and to drive the left and right driving wheels on an uneven roadbed or the like. It is necessary to switch the switch every time when the vehicle slips alternately. In the case of a normal self-propelled rolling machine, the operator needs to operate the steering wheel with one hand and operate the forward / reverse lever with the other hand. This is not desirable for safety because it is necessary to release one hand when operating the switch. In addition, since the braking device built in the hydraulic motor is slid, there is a problem that the life of the braking device is shortened when frequently used.

On the other hand, in the case of FIG. 4, it is not necessary for the operator to judge which of the left and right sides is slipping, and by using the foot switch, it is not necessary to release the hand from the handle or the lever. Better than the case. However, only on the forward side (or, in some cases, on the reverse side), the diverter valve 6
In this state, if the vehicle is operated backward (forward if there is a diverting valve on the reverse side), the diverting valve becomes a merging valve. In such a case, the amount of oil flowing through the left and right hydraulic motors 8a and 8b will differ due to the difference between the inner and outer wheels of the drive wheels, and the outlet side of the hydraulic motor 8a or 8b with the larger amount of oil and the flow dividing valve 6 ( In this case, an unusual pressure is generated between the pressure and the junction valve), and there is a possibility that the devices and the pipelines may be damaged. For this reason, there is a problem that it cannot be used unless the steering is in a straight running state.

[0008]

In the drive unit of a self-propelled rolling machine, two left and right hydraulic motors arranged in parallel to one hydraulic pump are connected to the front or rear drive wheels. When used, when the drive wheel attached to one motor slips, the oil discharged from the pump flows to the slip motor because the two motors are connected in parallel. The driving wheel opposite to the side loses the driving force and the rolling machine stops running. The present invention provides a differential lock circuit for solving this problem.

[0009]

Means for Solving the Problems (1) In the drive unit of the self-propelled rolling machine, in order to drive the front wheel or the rear wheel forming the left and right pair, two left and right wheels arranged in parallel with one hydraulic pump 1 are used. In a drive device using two hydraulic motors 8a and 8b connected via pipes a1 and a2, a differential lock mechanism provided with flow dividing valves 6a and 6b on the left and right hydraulic pipes a1 and a2 is provided. To detect the forward / backward movement of the compressor, so that the shunt valve 6a, 6b is interposed only on the front side of the driving hydraulic motors 8a, 8b during forward or backward travel,
Even if the rolling machine is not in the straight running state, the pressure oil can be supplied from the auxiliary pump 2 to escape from the running impossible state. (2) The differential lock mechanism has a pair of electromagnetic switching valves 4a and 4b on pipes d1 and d2 branched from a pipe a1 connected to one hydraulic pump 1, and the pair of electromagnetic switching valves. 4
a and 4b, one electromagnetic switching valve 4a is connected to one hydraulic motor 8a via a line d1, and the other electromagnetic switching valve 4b is connected to the other hydraulic motor 8b via a line d2. And a line a connected to the hydraulic pump 1
A diversion valve 6a connectable to the electromagnetic switching valves 4a and 4b is provided between the two pipelines d1 and d2 branching from 1. When the electromagnetic switching valves 4a and 4b are switched, the hydraulic pump 1 The pipeline a1 to be connected and the pipelines d1 and d2 leading to the hydraulic motors 8a and 8b are configured to be connected via the flow dividing valve 6a, and further branch off from the pipeline a1 connected to the hydraulic pump 1. A pair of check valves 7a and 7b are disposed between the pipes d1 and d2 through a pipe g1, and a pipe c and a pipe connected to the auxiliary motor 2 at an intermediate position between the pair of check valves 7a and 7b. A pair of solenoid-operated directional control valves 5a and 5b on pipes e1 and e2, which are connected to each other via a path f and are also branched from the other pipe a2 connected to the one hydraulic pump 1;
Of the pair of electromagnetic switching valves 5a and 5b, one electromagnetic switching valve 5a is connected to one hydraulic motor 8a via a line e1, and the other electromagnetic switching valve 5b is connected to the other hydraulic motor via a line e2. 8b, and a flow dividing valve 6b which can be connected to the electromagnetic switching valves 5a, 5b between two lines e1, e2 branched from the other line a2 connected to the hydraulic pump 1. Are provided, and the electromagnetic switching valves 5a and 5b are provided.
Is switched, the pipeline a2 connected to the hydraulic pump 1 and the pipelines e1 and e2 communicating with the hydraulic motors 8a and 8b are connected via the flow dividing valve 6b. A pair of check valves 7c and 7d are provided between the pipes e1 and e2 branching from the other pipe a2 connected to the valve 1.
Is disposed in the pipe g2, and the pair of check valves 7c and 7d
At an intermediate position between the pipes c and f connected to the auxiliary motor 2.

[0010]

1 is a hydraulic circuit diagram of the present invention, FIG.
Is an electric circuit diagram. Now, the present invention uses a flow dividing valve similar to that of FIG. 4, and in order to solve the problems of the prior art in FIG. 4, the flow dividing valve 6a is provided on each of the forward side and the reverse side.
And 6b, so that the oil flows only to the forward-side flow dividing valve 6a when the vehicle moves forward, and the oil flows only to the reverse-side flow dividing valve 6b when the vehicle moves backward. Further, the differential lock device has a detection mechanism for detecting a traveling direction of the rolling machine, and can escape from the traveling impossible state in any state of the rolling machine.

The differential lock device will be further described with reference to FIG. 1. A pair of electromagnetic switching valves 4a and 4b are provided on a pipeline a1 connected to one hydraulic pump 1, and one electromagnetic switching valve 4a is provided.
Is connected to one hydraulic motor 8a via a conduit d1. The other electromagnetic switching valve 4b is connected to the other hydraulic motor 8b via a line d2.

The flow dividing valve 6a is provided between the two conduits d1 and d2. In the state of FIG. 1, the electromagnetic switching valves 4a and 4b and the flow dividing valve 6
Although a is not connected, when the electromagnetic switching valves 4a and 4b are switched, the pipe a1 and the pipes d1 and d2 communicating with the hydraulic motors 8a and 8b are connected via the flow dividing valve 6a.

Check valves 7a and 7b are disposed between the pipes d1 and d2 by a pipe g1, and an auxiliary motor 2 is provided at an intermediate position between the check valves 7a and 7b via a pipe c and a pipe f. It is connected to the.

Similarly, a pair of solenoid-operated directional control valves 5a and 5b are also provided on the other conduit a2, and the conduit e is provided in the same manner as the above configuration.
At 1 and e2, they are connected to the hydraulic motors 8a and 8b. A flow dividing valve 6b and check valves 7c and 7d are provided between the pipes e1 and e2 via a pipe g2.

When the engine 10 is started in FIG. 1 and a parking brake switch (not shown) is turned off, FIG.
A of the relay Ra shown in FIG. a
(3) is excited, and the pressure oil from the switching auxiliary pump 2 passes through the pipe b, and the built-in braking device 9 of the driving hydraulic motors 8a, 8b.
a and 9b, and the drive hydraulic motors 8a and 8b become rotatable.

In the normal state, SOL. b1 (4
a), SOL. b2 (4b), SOL. c1 (5a) and SOL. Since c2 (5b) is not excited, when pressure oil flows from the drive hydraulic pump 1 to the forward side or the reverse side,
When moving forward, SOL. b1 (4a) and SOL. b2 (4
Pressure oil flows to the drive hydraulic motors 8a and 8b via b). And SOL. c1 (5a) and SOL. c2 (5
The oil returns to the hydraulic pump 1 via b). In reverse, oil flows on the reverse route.

If one of the drive wheels slips and it becomes necessary to operate the differential lock device, a foot switch 19 provided on the driver's seat or a switch 20 provided on the operation panel (see FIG. 2). Is turned on, and the relay Rc (2
2) is excited to turn on the A contact 22a of the relay Rc.
At that time, the limit switch LS (18) for detecting the operation of the forward / reverse lever remains OFF when the vehicle is moving forward, and the relay R
b through the B contact 21b of SOL. b1 (4a) and S
OL. b2 (4b) is excited. Therefore, in the normal case, SOL. b1 (4a) and SOL. The pressure oil that has directly flowed to the drive hydraulic motors 8a and 8b via b2 (4b) flows through the flow dividing valve 6a. as a result,
Approximately the same amount of pressure oil flows through the driving hydraulic motors 8a and 8b, so that the rolling machine can escape from the running impossible state.

At this time, if the steering of the rotary press is operated and the vehicle is not running straight, the required oil amount of the drive hydraulic motors 8a and 8b differs depending on the difference between the inner and outer wheels of the drive wheels. In order to compensate for the different oil amount, the pressure oil discharged from the auxiliary pump 2 is supplied from the check valve 7a or 7b via the pipe c. In this state, when the oil flowing out of the driving hydraulic motors 8a and 8b flows into the flow dividing valve 6b (in this case, a merging valve), the flow dividing valve 6b controls the amount of oil flowing from the driving hydraulic motors 8a and 8b. Are caused to substantially equalize each other, and an abnormal pressure is generated between the hydraulic motor 8a or 8b on the side with a large amount of oil and the flow dividing valve 6b. To prevent this, SO
L. c1 (5a) and SOL. c2 (5b) is returned to the hydraulic pump 1 without excitation without passing through the flow dividing valve 6b.

In reverse, the limit switch (LS) 18 for detecting the operation of the forward / reverse lever is turned on, so that the relay Rb (21) is excited, the B contact 21b of the relay Rb is turned off, and the SOL. b1 (4a) and SOL. b2
(4b) is demagnetized, and at the same time, the A contact 21a of the relay Rb is turned ON, and SOL. c1 (5a) and SO
L. c2 (5b) is excited, and the pressure oil flows in a direction opposite to that at the time of forward movement.

The above-mentioned foot switch 19 of the switch for the differential lock device is a momentary type (a type that is turned ON only while the switch is being operated), and the switch 20 on the operation panel is an alternate type (the switch is operated again once the switch is operated). Use the type whose switch is ON until the switch is turned on. Then, when working on uneven roadbed or the like in advance, the switch 20 on the operation panel should be turned off.
By setting N, it is possible to prevent running failure due to slippage of the drive wheels.

[0021]

As compared with the known one shown in FIG. 3, it is not necessary to check the driving wheel on the slipping side, and at the same time, the switch is operated even when the left and right driving wheels slip alternately on an uneven roadbed or the like. It is possible to escape from the state in which the compressor cannot travel without switching. In addition, by using the foot switch 19, the operation can be performed without releasing the hand from the steering handle and the forward / reverse lever during driving, and safety is further improved.

In comparison with the known motor shown in FIG. 4, when the vehicle is moving forward or backward, the flow dividing valves 6a and 6b are always interposed in front of the driving hydraulic motors 8a and 8b so that the driving hydraulic motors 8a and 8b After that, the oil was allowed to flow to the hydraulic pump 1 without passing through the flow dividing valve. At the same time, when the steering is not in the straight running state, the difference in oil amount due to the difference between the inner and outer wheels of the drive wheels is determined by using the pressure oil of the auxiliary pump 2 as check valves 7a, 7b, 7c and 7c.
By supplying from d, it is possible to escape from the running impossible state regardless of the state of the compactor.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram of the present invention.

FIG. 2 is an electric circuit diagram of the present invention.

FIG. 3 is a hydraulic circuit diagram of a known differential lock device using a braking device of a driving hydraulic motor.

FIG. 4 is a hydraulic circuit diagram of a known differential lock device using a flow dividing valve.

FIG. 5 is a hydraulic circuit diagram of a general self-propelled rolling machine.

[Description of Signs] 1 (for driving and traveling) Hydraulic pump 2 (for replenishing oil) Auxiliary pump 3 (for releasing brake device of driving hydraulic motor) Solenoid valves 4a, 4b (Turning on / off differential lock device during forward movement) Solenoid valves 5a, 5b (for turning on and off the differential lock device during reverse) Solenoid valves 6a, 6b (for operating the differential lock mechanism) Dividing valves 7a, 7b, 7c, 7d (auxiliary pump) Check valve 8a, 8b Hydraulic motor for driving 9a, 9b Braking device (with built-in hydraulic motor for driving) 10 Engine of rolling mill 11 Oil tank 12 (Either left or right braking device) Select whether to activate)
Solenoid valve 13 Check valve (for adjusting the braking force) 14 Throttle valve (for adjusting the braking force) 15 Power supply 16 Fuse 17 Relay (for releasing the braking device of the driving hydraulic motor) 18 Limit switch 19 (to detect whether the compressor is moving forward or backward) Foot switch (for turning on / off the differential lock device) (momentary type) 20 Switch (on the operation panel for turning on / off the differential lock device) (Alternate type) 21,21a, 21b (Detects which differential lock device to actuate forward / backward) Relay 22,22a (To turn on / off the differential lock device) Relay 23 (Displays the on / off status of the differential lock device) Pilot lamp)

Claims (2)

[Claims] In a drive unit of a self-propelled rolling machine, two left and right hydraulic motors (1) are arranged in parallel with one hydraulic pump (1) to drive a pair of left and right front wheels or rear wheels. 8a, 8b) connected via pipelines (a1, a2), the drive device comprising: a flow dividing valve (6) on the left and right hydraulic pipelines (a1, a2);
a, 6b) is provided to detect the forward / backward movement of the compressor, and to detect the forward / backward movement of the rotary machine, and to provide the above-mentioned only on the front side of the driving hydraulic motors (8a, 8b) during forward or backward travel. Self-propelled, characterized in that the flow dividing valves (6a, 6b) are interposed, and even if the compressor is not in the straight running state, the driving oil can be replenished from the auxiliary pump (2) to escape the inoperable state. Differential locking device for a compacting machine. 2. A differential lock mechanism comprising: a pair of electromagnetic switching valves (4) on pipes (d1, d2) branched from a pipe (a1) connected to one hydraulic pump (1).
a, 4b), and the pair of electromagnetic switching valves (4a, 4b)
Of these, one electromagnetic switching valve (4a) is connected to one hydraulic motor (8a) via a pipe (d1), and the other electromagnetic switching valve (4b) is connected to the other hydraulic motor via a pipe (d2). A pipe (a1) connected to the motor (8b) and further connected to the hydraulic pump (1)
A flow dividing valve (6a) connectable to the electromagnetic switching valves (4a, 4b) is provided between the two pipelines (d1, d2) branching from the valve, and the electromagnetic switching valves (4a, 4b) are switched. And a pipeline (a1) connected to the hydraulic pump (1) and pipelines (d1, d2) communicating with the hydraulic motors (8a, 8b) are connected via the flow dividing valve (6a). And a line (a) connected to the hydraulic pump (1).
A pair of check valves (7a, 7b) is disposed by a pipe (g1) between the pipes (d1, d2) branching from 1), and an intermediate position between the pair of check valves (7a, 7b). And auxiliary motor (2)
Are connected via a pipeline (c) and a pipeline (f), and similarly a pipeline (e1, branching from the other pipeline (a2) connected to the one hydraulic pump (1)). e2) has a pair of electromagnetic switching valves (5a, 5b), and one of the pair of electromagnetic switching valves (5a, 5b) is connected to one of the electromagnetic switching valves (5a) via a pipe (e1). The other electromagnetic switching valve (5b) is connected to the other hydraulic motor (8b) via a pipe (e2), and further connected to the hydraulic pump (1). Between the two pipelines (e1, e2) branched from the other pipeline (a2)
A flow dividing valve (6) connectable to the electromagnetic switching valves (5a, 5b).
b) is provided and when the electromagnetic switching valves (5a, 5b) are switched, the pipeline (a2) connected to the hydraulic pump (1) and the pipeline (e) leading to the hydraulic motors (8a, 8b).
1, e2) are connected via the flow dividing valve (6b), and the lines (e1, e2) branched from the other line (a2) connected to the hydraulic pump (1). ), A pair of check valves (7c, 7d) is disposed in a line (g2), and a line connected to the auxiliary motor (2) at an intermediate position between the pair of check valves (7c, 7d). The differential lock device for a self-propelled rolling machine according to claim 1, wherein the differential lock device is configured to be connected to (c) via a pipeline (f).