JPS6015729Y2 - Steering hydraulic circuit for a vehicle with two engines - Google Patents

Description

[Detailed explanation of the invention] This invention relates to a steering hydraulic circuit for a vehicle that is equipped with two engines and is driven by two engines. Even if one hydraulic pump stops, the pressure oil from the hydraulic pump being driven by the other engine is routed to the circuit on the failed engine side, allowing steering to be performed.

In a transport truck that is configured with the same steering hydraulic circuit consisting of a hydraulic pump, a flow control valve, a control valve, a steering cylinder, etc. driven by two engines, each engine is driven by one engine. - If the engine fails, the hydraulic pump will stop and one of the steering hydraulic circuits will become inoperable, making steering impossible.

Therefore, it is necessary to carry out repairs immediately, but if the transport truck is large, it is difficult to tow it and repairs must be carried out on the spot.During repairs, hydraulic oil may spill out and stain the traveling road surface. Because it took time to contact and arrive at the repair equipment, breakdowns in the middle of the route could hinder the operation of other vehicles.

This invention allows even if one of the two engines breaks down and the hydraulic pump stops while the vehicle is running, the pressure oil of the hydraulic pump driven by the other engine is transferred to the circuit of the faulty pump. The purpose of this device is to enable stable steering by guiding an equal amount using a simple device, so that the vehicle can continue to run.

In this invention, when one engine breaks down while driving, the shutoff valve of the communication circuit is opened, and the shutoff valve of one volume control valve circuit is closed, and the hydraulic pressure driven by the other engine is The pump's pressure oil is supplied in equal amounts to the malfunction side circuit and the normal side circuit of the engine using the distribution valve, thereby making it possible to steer the transport vehicle without causing an imbalance in the steering angle and steering speed. This is what I did.

Embodiments of the present invention will be described in detail with reference to the drawings.

The figure shows the hydraulic circuit of a transport vehicle having two engines, with hydraulic cylinders 7'2a located at the front and rear positions of the transport vehicle, respectively.
2b and the driving engine la.

1b is installed.

Hydraulic circuits for steering are constructed on the front and rear sides of the vehicle centering around these hydraulic pumps 2a and 2b.

In this steering hydraulic circuit, hydraulic pumps 2a and 2b suck oil from hydraulic oil tanks 3a and 3b and discharge pressure oil.

Pressure oil is supplied to the steering cylinders 6a, 6b via flow control valves 4a, 4b and control valves 5a, 5b.

Relief valves 7a*7b are provided to protect the circuit.

The present invention provides a communication circuit for each of these steering hydraulic circuits.

That is, communication circuits 8a, 8b and 9at9b
The communication circuits 8a, 8b and 9a,
9b through a circuit 10, and a check valve 12 is connected to these circuits.
and a distribution valve 11 are provided.

Further, there are provided a communication pipe 15 between the shutoff valves 13a and 13b which are in an open state during a normal circuit, the shutoff valve 14 which is in a closed state, and the hydraulic oil tank 3av3b.

In the steering hydraulic circuit configured as described above, when the two engines are in a normal state, the hydraulic pump 2a driven by the engine 1a sucks oil from the hydraulic oil tank 3a and discharges pressure oil.

This pressure oil is controlled at a constant flow rate by the flow control valve 4a and sent to the control valve 5a via the shutoff valve 13a.

The control valve 5a is connected to the steering wheel by a mechanical link, and the port of the control valve 5a is switched by operating the steering wheel depending on the road conditions, and the port of the control valve 5a is switched between the front side of the steering cylinder 6a and the head side of the steering cylinder 6a. The vehicle body is turned to the left or right by sending pressure oil to the side to extend and retract the steering cylinder 6a, and by moving the wheels connected to the steering cylinder 6a by levers and shafts.

The discharge amount of the hydraulic pump 2a increases proportionally as the rotation speed of the engine 1a increases, but the pressure oil exceeding the control flow rate of the flow control valve 4a is returned from the flow control valve 4a to the hydraulic oil tank 3a as surplus oil. It will be done.

When the vehicle is traveling straight, the pressure oil from the hydraulic pump 2a returns to the hydraulic oil tank 3a from the control valve 5a without operating the steering cylinder 6a.

The steering hydraulic circuit on the other hydraulic pump 2b side also functions in a similar manner.

Next, if one engine 1a suddenly breaks down while driving,
The hydraulic pump 2a stops and no longer discharges pressure oil.

In this situation, in order to guide the pressure oil discharged from the hydraulic pump 2b driven by the other normal engine 1b to the engine 1a side, the shutoff valve 14 is opened and the shutoff valve 1
3a and 13b are closed.

Accordingly, the pressure oil from the hydraulic pump 2b passes through the communication circuit 8b, and since the communication circuit 8a is closed by the check valve 12, the oil is sent to the circuit 10 and enters the distribution valve 11.

Since the distribution valve 11 divides the inflow oil equally and discharges it in two directions, the pressure oil of the hydraulic pump 2b is divided equally by the distribution valve 11 and sent to the communication circuits 9a and 9b, respectively.

As a result, the pressure oil of the hydraulic pump 2b enters both the control valve 5a of the failed circuit and the control valve 5b of the normal circuit.

Therefore, if the driver operates the steering wheel to move the control valve 5av5b, the steering cylinder 6.6
Pressure oil is sent to each of the points b and the vehicle is steered.

Flow control valves 4a and 4b when only one of these is used
Since the shutoff valves 13a and 13b are closed, no pressure oil flows.

In addition, when only one hydraulic pump is driven in this way, oil is sucked from one hydraulic oil tank and the return oil is returned to both hydraulic oil tanks, so the left and right hydraulic oil tanks 3at3b
Although this causes an imbalance in the amount of oil, there is no problem because the communication pipe 15 allows oil to be moved between the hydraulic oil tanks 3a and 3b.

In this way, when two engines are used, steering can be performed even if one engine fails.

According to the present invention, even if one engine breaks down in a transport vehicle with two engines, the other normal engine can be used for steering with a simple device.
Therefore, even if one engine breaks down, the train can continue to operate without having to move the vehicle, which has the effect of reducing the impact of vehicle suspension on work plans.

[Brief explanation of the drawing]

The figure is a circuit diagram showing a steering hydraulic circuit according to the present invention. 1a, 1b...Engine, 2a, 2b...
... Hydraulic pump, 3 a, 3 b ... Hydraulic oil tank, 4 a, 4 b ... Flow rate control valve, 5 a,
5 b...Control valve, 6a, 6
b...Steering cylinder, 7a, 7b------
Relief valve, aat 8bt 9at 9b
......Communication circuit, 10...Circuit, 11.
...Distribution valve, 12...Check valve, 13a,
13b...Shutoff valve, 4...Shutoff valve, 1
5...Communication pipe.

Claims (1)

[Scope of utility model registration request] A shutoff valve is installed in each circuit that has a steering hydraulic circuit of the same system consisting of a hydraulic pump driven by two engines, a flow control valve, a control valve, a steering cylinder, etc., and the control valve is connected to the shutoff valve of the circuit. The two sides are connected by a communication circuit equipped with a distribution valve and a check valve, and the flow control valve side from the hydraulic pump in the one side circuit is connected by a communication circuit equipped with a check valve installed opposite to the above check valve. A steering hydraulic circuit for a vehicle having two engines, characterized in that both communication circuits are connected by a circuit provided with a shutoff valve.