JPS6135485Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an emergency steering device for a vehicle equipped with a hydraulic steering device.

The hydraulic steering device operates by being supplied with pressure oil from a hydraulic pump driven by the engine, and naturally its operational function stops when the engine stops. For this reason, if the engine stops due to engine trouble while the vehicle is running, the steering cannot be operated, resulting in a dangerous situation.

Various emergency steering devices have been devised and implemented in the past for such cases, but all of them have the problem of being complicated and expensive.

The present invention was developed in consideration of the above-mentioned problems, and has a simple structure by using the running energy of the vehicle to drive an emergency hydraulic pump and using the hydraulic pressure from this to operate the steering device. The present invention aims to provide an emergency hydraulic steering device that can be obtained at low cost.

The configuration will be explained below based on the embodiment shown in the drawings.

In the figure, 1 is a regular hydraulic pump driven by an engine 2, 3 is a steering circuit that supplies hydraulic pressure from this hydraulic pump 1 to a hydraulic steering device (not shown), and 4 is a switching device installed in this steering circuit 3. It is a valve. 5 is a cam fixed to a propulsion shaft 6 that rotates together with the axle of the vehicle; 7 is an emergency hydraulic pump that is reciprocated by this cam 5; its suction port 7a is connected to an oil tank via a check valve 8; At 9,
Further, the discharge port 7b is connected to the switching valve 4 via a check valve 10. The piston of this hydraulic pump 7 is urged toward the cam by a spring 7c.

The switching valve 4 has a first regular position 4 where hydraulic pressure from the regular hydraulic pump 1 is sent to the hydraulic steering device.
a, a first emergency position 4b where hydraulic pressure from the emergency hydraulic pump 7 is sent to the steering device, and a second normal position 4c where hydraulic pressure is sent from the hydraulic pump 1 to the rod side of the hydraulic pump 7. It has a second emergency position 4d that connects the rod side of the hydraulic pump 7 and the oil tank 9, and uses the pressure of the normally used hydraulic pump 1 as a pilot to enter the first and second normal positions 4a and 4c, and is not in normal use. When the hydraulic pump 1 loses pressure, the spring moves it to the first and second emergency positions 4b, 4.
d.

In the above configuration, when the engine 2 rotates and the regular hydraulic pump 1 is driven and there is future hydraulic pressure, the switching valve 4 is moved to the first and second regular positions 4.
a, 4c. Therefore, the pressure oil from the pump 1 is fed to the steering device through the first normal position 4a, and normal steering operation is performed.
Also, at this time, the pressure oil from the hydraulic pump 1 is sent to the rod side of the emergency hydraulic pump 7 through the second normal position 4c, the piston rod is separated from the cam 5, and the hydraulic pump 7 becomes inactive. Become.

When the engine 2 stops and the supply of hydraulic pressure from the hydraulic pump 1 stops, the switching valve 4 becomes the first and second emergency positions 4b and 4d, the inoperable state of the piston pump 7 is released, and the piston pump The discharge port 7 is connected to the steering circuit 3. When the vehicle is running due to inertia in this state, the propulsion shaft 6 is rotating, which drives the piston pump 7 via the cam 5, and the discharged oil is sent to the steering circuit 3. The steering device becomes operable.

The present invention is as described above, and in a vehicle equipped with a hydraulic steering device, an emergency hydraulic pump is connected to the propulsion shaft 6 of the vehicle via a clutch that is released by hydraulic pressure. In the steering circuit 3 that connects the regular hydraulic pump 1 driven by the engine 2 and the steering device, regular positions 4a and 4 are used to supply hydraulic pressure from the regular hydraulic pump 1 to the steering circuit 3 and the clutch.
c, and emergency positions 4b and 4d for feeding oil discharged from the emergency hydraulic pump 7 to the steering circuit 3 and draining pressure oil to the clutch. Since the emergency hydraulic steering device is constructed by interposing the switch according to the discharge pressure, the emergency hydraulic pump 7 is driven using the running energy of the vehicle, and the steering device is operated by the hydraulic pressure of the emergency hydraulic pump 7. It is possible to obtain an emergency hydraulic steering device that is operable, has a simple configuration, and is inexpensive. Further, according to the present invention, the emergency hydraulic pump 7 is operated by the rotation of the propulsion shaft 6 only in an emergency when the engine 2 has stopped, and is not constantly rotating. No power loss occurs.

[Brief explanation of drawings]

The drawing is a hydraulic circuit diagram showing an embodiment of the present invention. 1 and 7 are hydraulic pumps, 2 is an engine, 3 is a steering circuit, 4 is a switching valve, 4a and 4c are normal positions, 4b and 4d are emergency positions, and 6 is a propulsion shaft.

Claims (1)

[Scope of utility model claims] In a vehicle equipped with a hydraulic steering device, an emergency hydraulic pump is connected to the propulsion shaft 6 of the vehicle via a clutch that is released by hydraulic pressure, and a regular hydraulic pump driven by the engine 2 is connected to the propulsion shaft 6 of the vehicle. In the steering circuit 3 that connects the hydraulic pump 1 and the steering device, there are regular positions 4a and 4c for supplying hydraulic pressure from the regular hydraulic pump 1 to the steering circuit 3 and the clutch, and an emergency hydraulic pump 7.
Emergency positions 4b, 4 supply the discharged oil to the steering circuit 3 and drain the pressure oil to the clutch.
An emergency hydraulic steering device characterized in that a switching valve 4 having a switch valve d and a switching valve 4 is interposed so as to be switched by the discharge pressure from a regular hydraulic pump 1.