JPH0120167Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a control device for a hydraulic vehicle height adjustment device for an automobile.

In an automobile, a vehicle height adjustment mechanism consisting of a hydraulic cylinder device is incorporated into the suspension system of each of the front, rear, left, and right wheels, and the vehicle height can be changed by controlling the increase or decrease of oil in the cylinder using an oil pump device. For example, Japanese Patent Application Publication No. 57-178911
It has already been publicly known in publications such as No.

In the above-mentioned hydraulic vehicle height adjustment device, a vehicle height sensor is usually provided for each wheel, and the operation of the oil pump device is controlled based on a signal from the vehicle height sensor.

The present invention is a hydraulic vehicle height adjustment device in which an oil pump is operated by turning on a vehicle height adjustment switch to raise the vehicle height to a predetermined value. The purpose of this invention is to simplify the structure and reduce costs by making it possible to control the operation.The present invention will be described below with reference to the accompanying drawings.

In FIG. 1, A is an oil pump device, and as shown in FIG. 2, the oil pump device A includes an oil tank 1, an oil pump 2, and a control valve 3.
When the oil pump 2 rotates in one direction, the oil in the oil tank 1 is sucked up through the check valve 4, and is fed to the oil path a by the check valve 5. As shown in Fig. 1, oil is supplied from oil passage a through pipe b into hydraulic cylinder devices B1 and B2 for adjusting the vehicle height of the left and right front wheels, and at the same time, hydraulic pressure for adjusting the vehicle height of the left and right rear wheels is supplied. The oil in the oil tank 1 is supplied to the cylinder device B3, and when these hydraulic cylinder devices B1, B2, and B3 are extended to raise the vehicle height, and the oil pump 2 is rotated in the opposite direction, the oil in the oil tank 1 is supplied to the check valve 6. It is sucked up through the oil passage c and supplied to the end face of the valve body 3a of the control valve 3, and then flows into the oil tank 1 through the oil passage d having an orifice d', and the oil pressure is used to close the valve of the control valve 3. The body 3a operates against the spring 3b,
The oil in each cylinder device B1, B2, and B3 passes through the drain oil passages e and f, and the oil in each cylinder device B1, B2, and B3 flows from the pipe b to the oil tank 1 through the drain oil passages e and f.
The cylinder devices B1, B2, and B3 contract with the weight of the vehicle to lower the vehicle height.

In the present invention, as shown in FIG. 2, an oil pressure switch 7 is provided that operates by detecting the pressure in the oil passage a on the side that raises the vehicle height, and the oil pressure switch 7 is used as a vehicle height sensor. When the cylinder devices B1, B2, and B3 all reach a predetermined height, the oil pressure switch 7 is activated and the operation signal of the oil pressure switch 7 is used to stop the operation of the oil pump 2. be.

That is, when the vehicle height adjustment switch installed near the driver's seat is turned on and the oil pump 2 starts rotating, oil flows from the oil path a through the pipe b to each hydraulic cylinder device B1, B2, and the like as described above. B3, the oil pressure in each cylinder device increases, and when the oil pressure reaches a predetermined pressure (P1 in FIG. 3), the pressure is applied to each hydraulic cylinder device B.
1, B2, and B3 begin to extend and raise the vehicle height. During this operation, the operating stroke required for adjusting the vehicle height of each hydraulic cylinder device is almost constant, and during the extension operation, the oil pressure in oil passage a and pipe b is approximately as shown in Figure 3. The pressure is constant P1.

All hydraulic cylinder devices B1, B2 and B3
When the oil pressure is extended to a predetermined position and the vehicle body enters a normal posture in which further extension is restrained by a stopper (not shown), the oil pressure in the oil supply path rises rapidly as shown in FIG. When the oil pressure reaches the set operating value P2 of the oil pressure switch 7, the oil pressure switch 7 is activated, and the oil pump 2 stops rotating in response to the activation signal to adjust the vehicle height, that is, the posture of the vehicle body. Control is complete.

As described above, the present invention focuses on the fact that in a hydraulic vehicle height adjustment system, each of the front and rear hydraulic cylinder devices are connected to a single pipe, and the oil pump supplies oil to each hydraulic cylinder device. By providing an oil pressure switch in the supply path that operates at a set oil pressure value higher than the oil pressure value required for each hydraulic cylinder device to extend, this one oil pressure switch can maintain the normal vehicle body posture. It functions as a vehicle height sensor that detects the temperature and stops the oil pump.
The vehicle height sensors that were conventionally provided in the front, rear, left and right wheel suspension units can be omitted, and the number of parts can be significantly reduced, the configuration can be significantly simplified, and costs can be reduced compared to conventional devices.

If the oil pressure switch 7 is incorporated into the unit of the oil pump device A as in the illustrated embodiment, it can be very compact in terms of space and is extremely effective. can be provided at any position of the oil supply path to each hydraulic cylinder device.

In addition, the illustrated embodiment shows an example in which the present invention is applied to a vehicle in which the height adjustment of the left and right rear wheels is performed by one hydraulic cylinder device B3. Needless to say, it is also applicable to a system in which hydraulic cylinder devices provided in each unit are used.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a hydraulic circuit for vehicle height control showing an embodiment of the present invention, Fig. 2 is a diagram showing an example of the oil pump device shown in Fig. 1, and Fig. 3 is a diagram showing changes in oil pressure during vehicle height adjustment. FIG. A...Oil pump device, B1, B2, B3...
...Hydraulic cylinder device, 1...Oil tank, 2...
...Oil pump, 3...Control valve, 7...Oil pressure switch.

Claims (1)

[Scope of utility model registration request] A vehicle height adjustment mechanism consisting of a hydraulic cylinder device is incorporated into the front, rear, left and right wheel suspensions, and an oil pump is operated to supply oil to each of the above-mentioned hydraulic cylinder devices to raise the vehicle height and bring the vehicle into a high normal posture. In a hydraulic vehicle height adjustment device that is capable of lowering the vehicle height and placing the vehicle body in a low normal posture by draining the oil in the device,
An oil pressure switch is connected to each hydraulic cylinder device from the oil pump to stop the operation of the oil pump by operating at a set oil pressure value higher than the oil pressure value required for the extension operation of all the above hydraulic cylinder devices. 1. A control device for a hydraulic vehicle height adjustment device for an automobile, characterized in that the control device is provided in an oil supply path for an automobile.