JPH0330523B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle height adjusting device that lowers the pressure of a gas chamber at a constant speed when lowering the vehicle height by exhausting air from the vehicle height adjusting gas chamber.

A vehicle height adjustment device is installed in vehicles such as automobiles and motorcycles, and is used to arbitrarily change the vehicle height and maintain an appropriate ground clearance by supplying and discharging high-pressure air to a gas chamber provided in a suspension system. This is what makes it possible.

In the vehicle height adjustment device, when lowering the vehicle height, a relief solenoid valve for opening to the atmosphere, which is an exhaust valve, is opened intermittently to selectively remove high-pressure air from each gas chamber of the suspension system at the front and rear of the vehicle. However, the air passages leading to the gas chambers at the front and rear of the vehicle are equipped with solid orifices, and due to the load distribution in the vehicle, the pressure in the front gas chamber is low, while the pressure in the rear gas chamber is high. As a result, the rate of pressure drop in each gas chamber will be different. That is, the pressure drop rate is slow on the low pressure side, and the pressure drop rate is fast on the high pressure side, making it difficult to control the manual adjustment of each gas chamber, that is, the manual adjustment of the vehicle height.

This also applies to the same gas chamber. For example, the pressure of the gas supplied to the rear side gas chamber is set to a lower limit of 2.0Kg/cm ² and an upper limit of 6.4Kg/cm ² , and if the gas chamber is continuously exhausted, The internal pressure gradually decreases, and as the internal pressure decreases, the rate of decrease gradually slows down, resulting in the same problem as above.

In view of the above-mentioned problems, the present inventors have created the present invention in order to effectively solve the problems.

An object of the present invention is to maintain a constant pressure drop rate when lowering the vehicle height by removing high-pressure air from each gas chamber in a vehicle height adjustment device. The reason is that pressure adjustment can be easily performed.

The present invention is characterized by selectively supplying and discharging high-pressure air to each of the vehicle height adjustment gas chambers formed in the front and rear suspension systems of the vehicle using a common pressure source or exhaust valve. In a vehicle height adjustment device that adjusts the height,
The internal pressure state of each of the above gas chambers is measured with a pressure sensor,
Based on the control of the control device, when the exhaust valve is intermittently opened and closed, its opening time is changed in accordance with the internal pressure of each gas chamber to be exhausted, so that the pressure is reduced in equal flux.

An embodiment of the present invention will be described below based on the accompanying drawings.

FIG. 1 shows a configuration diagram of a vehicle height adjustment device according to the present invention, and FIG. 2 shows a system diagram of the same adjustment device. In this embodiment, it is configured as a vehicle height adjustment device for a motorcycle.

In FIGS. 1 and 2, reference numeral 1 denotes a compressed air generator, which is comprised of a compressor 2 that compresses atmospheric air to generate high-pressure air, and a dryer 3 that removes moisture from the high-pressure air. Reference numerals 4 and 4 indicate front forks at the front of the vehicle, and 5 and 5 indicate rear suspensions at the rear of the vehicle, each of which has a gas chamber (not shown) formed therein that expands and contracts its length in the axial direction to change the vehicle height. ing. The compressed air generator 1 and the gas chambers of the front forks 4, 4 and rear suspensions 5, 5 are connected by an air pipe 6, and there is a part in the middle of the air pipe 6, as shown in the figure. A control valve unit 13 is provided which includes solenoid valves 7 and 8 which are front and rear switching valves, a relief solenoid valve 9 which is an exhaust valve for opening to the atmosphere, a pressure sensor 10, a pressure limiter 11, and further includes a check valve 12. .

In the above configuration, the compressor 2 and the solenoid valves 7, 8, and 9 are operated based on commands from a control device 14 composed of, for example, a CPU. That is, by opening the solenoid valve 7 and closing the solenoid valve 8, the compressor 2
When activated, high-pressure air is supplied to each gas chamber of the front forks 4, 4 to raise the vehicle height at the front of the vehicle, and the solenoid valves 7, 8 are kept in the same state as above, and the relief solenoid valve 9 is activated. If you open and close the front forks 4 and 4 intermittently,
High-pressure air is gradually released from each gas chamber, lowering the vehicle height. Conversely, if the solenoid valve 8 is opened, the solenoid valve 7 is closed, and either the compressor 2 or the relief solenoid valve 9 is operated, high-pressure air is supplied and discharged to the gas chambers of the rear suspensions 5, 5, and the vehicle height at the rear of the vehicle is increased. Adjustments can be made. Note that when the vehicle height is not adjusted, both solenoid valves 7 and 8 are closed, and the compressor 2 is closed.
is stopped and the relief solenoid valve 9 is closed.

Generally, the loads applied to the front and rear parts of a vehicle are different, and therefore the pressure settings of the high-pressure air supplied to each gas chamber are also different between the front and rear parts. For example, in the gas chamber of front fork 4, the lower limit is 0.0
Kg/cm ² , upper limit is 1.0Kg/cm ² , while rear 5
In the gas chamber, the lower limit is 2.0Kg/cm ² and the upper limit is 6.4Kg/cm ²
is set. Therefore, the height adjustment of the front and rear of the vehicle is performed separately, and the solenoid valves 7 and 8 are used to select the front and rear of the vehicle.

Regarding the vehicle height adjustment device having the above configuration, furthermore, the manual/auto selection switch 1
5. Operating means such as a manual front/rear selection switch 16, a manual up/neutral/down selection switch 17, a vehicle height sensor 18 that outputs vehicle height information, a brake sensor 19 that detects the brake state, and a gas chamber in the front fork. A display 20 for digitally displaying the internal pressure of the engine, and a display 21 for digitally displaying the internal pressure of the gas chamber of the rear suspension. Output signals from each operating means and vehicle height sensor 18,
The output signal from the brake sensor 19 is sent to the control device 1.
4, and the displays 20 and 21 output and display the pressure value calculated by processing the pressure data obtained from the pressure sensor 10 in the control device 14 during social adjustment.

The vehicle height adjustment device as described above has a brake sensor 1
Based on the signal given from 9, if other requirements such as the fact that the brake has not been applied are met, the brake becomes ready for operation. The vehicle height adjustment method is as follows:
The manual/auto selection switch 15 allows manual vehicle height adjustment or automatic vehicle height adjustment. In the case of manual vehicle height adjustment, use switch 16 to select either the front or rear side, and use switch 17 to adjust the height up or down.
By selecting one of these, the driver can adjust the vehicle height according to his/her preference under a certain pressure limit while visually checking the changes in the pressure display on the display devices 20 and 21. On the other hand, in the case of automatic vehicle height adjustment, predetermined "OK", "HIGH", and "LOW"
Based on the vehicle height information output from the vehicle height sensor 18, etc., the vehicle height is adjusted so that whenever the vehicle height changes with respect to the standard vehicle height, the vehicle height is always set to the standard vehicle height ("OK" state). . In this case, the adjustment target is only the rear side, and the driver himself is not involved in adjusting the vehicle height.

In the case of manual vehicle height adjustment, the driver visually checks the internal pressure status of the front fork and rear suspension gas chambers displayed on the display devices 20 and 21, and selects the up/neutral/down selection switch 17. Operate to adjust the vehicle height appropriately. Therefore, manual vehicle height adjustment essentially involves adjusting the pressure in each gas chamber at the front and rear of the vehicle. In order to lower the vehicle height, when the relief solenoid valve 9 is intermittently opened and closed, the high pressure air in each gas chamber is released and the vehicle height is lowered. In this case, the present invention is configured such that the time period during which the relief solenoid valve 9 is kept open varies depending on the internal pressure state of each gas chamber at the front and rear of the vehicle. That is, when the internal pressure of the gas chamber is high, the time during which the relief solenoid valve 9 opens is shortened.
When the internal pressure of the gas pressure is low, the relief solenoid valve 9 is opened for a long time, so that the pressure decreases at a constant speed regardless of the internal pressure of the gas chamber. Therefore, the changes in the internal pressure of each gas chamber displayed on the displays 20 and 21 change at a constant speed, making it easier for the operator to control the pressure when manually adjusting it.

When discharging air from each gas chamber as described above,
The opening time of the relief solenoid valve 9 is made variable in proportion to the internal pressure state of each gas chamber.
The pressure sensor 10 detects the internal pressure of the gas chamber being evacuated, and the control device 14 controls the opening/closing operation of the relief solenoid valve 9 based on this pressure data.

In the above embodiment, a vehicle height adjustment device for a motorcycle has been described, but the present invention can of course be applied to a hydraulic type or various vehicle height adjustment devices for automobiles.

As is clear from the above description, according to the present invention,
When adjusting the pressure by evacuating gas chambers with different pressure states by intermittent opening and closing operations of a common exhaust valve, the opening time of the exhaust valve is changed in accordance with the internal pressure state of each gas chamber. This makes it possible to keep the rate of pressure drop in each gas chamber constant regardless of the internal pressure state of the gas chamber, making it easy to control the pressure when manually adjusting it.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a vehicle height adjustment device according to the present invention,
FIG. 2 is a control system diagram of the adjustment device. In the drawing, 2 is a compressor, 4 is a front fork, 5 is a rear action, 7 and 8 are solenoid valves for front/rear switching, 9 is a relief solenoid valve for opening to the atmosphere, 10 is a pressure sensor, 14 is a control device, and 20 and 21 are digital units. It is a pressure indicator.

Claims (1)

[Claims] 1. A vehicle height adjustment device that adjusts the vehicle height by selectively supplying and discharging high-pressure air to each of the vehicle height adjustment gas chambers formed in the front and rear suspension systems of the vehicle using a common pressure source or exhaust valve. in which the internal pressure state of each of the gas chambers is measured by a pressure sensor, and the control device changes the opening time of the exhaust valve during intermittent opening and closing operations in accordance with the internal pressure of each gas chamber to be exhausted; A vehicle height adjustment device characterized by depressurizing at a constant speed.