JPS61222809A - Level-control device - Google Patents

Abstract

PURPOSE:To make a car so as to keep its proper level even at the time of leaving the car intact for a long period of time, by holding a level detector operatable even when a traveling drive unit stops and feed or discharge of a fluid to or from a hydraulic chamber comes to a stop and, if the car becomes below its desired level, constituting a device so as to control the level. CONSTITUTION:When an ignition switch 21 is turned off, stopping an engine, and an off contact (a) is connected to a power source 17, a feeder circuit be tween a controller 15 and this power source comes off, thus this controller 15 stops its operation. On the other hand, since a level detector 16 is connected to the power source 17 at the upstream side of the ignition switch 21, it is energized with a continues rating current and continues its level detection even if the ignition switch 21 is off, and outputs a level detection signal DH. There fore, when the detected level becomes less than a second setting level, a relay switch 20 is turned on, making the controller 15 come into a state of being operated, thus it drives a compressor 10 and adjusts a car level. Thus, the car level is adjusted even at the time of leaving a car intact for a long period of time.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to increasing or decreasing the vehicle height by adjusting the fluid pressure in a fluid chamber that is interposed between the vehicle body and the wheels so that the vehicle height can be adjusted. This invention relates to a vehicle height control device that can perform

[Conventional technology]

As a conventional vehicle height control device, for example, 5AE8403
42 (Journal of the American Society of Automotive Engineers). There is something like that.

The device consists of a fluid chamber that is interposed between the vehicle body and wheels so that the vehicle height can be adjusted, and that can increase or decrease the vehicle height by adjusting the internal fluid pressure, and supplies high-pressure air to this fluid chamber. The system has a fluid pressure source consisting of a near compressor, an electric motor, etc., which can be operated, and an opening/closing valve that is driven to open and close by a control signal supplied from a controller is installed in the pipeline that communicates these. . Then, the controller is supplied with a vehicle height detection signal corresponding to the vehicle height from the vehicle height detector, an on/off signal from the ignition switch, etc. Based on these signals, the controller determines the on/off state of the ignition switch. The vehicle height is adjusted by executing a predetermined vehicle height adjustment logic according to the vehicle height.

[Problem that the invention seeks to solve]

However, with such conventional vehicle height adjustment devices, when the ignition switch is turned off after the vehicle is stopped, the vehicle height is read by the vehicle height detector 60 minutes after the switch is turned off, and the vehicle height is adjusted. If the detected vehicle height value is not within the predetermined target vehicle height range, the vehicle height adjustment is performed, and thereafter no vehicle height adjustment is performed until the ignition switch is turned on again. For example, a drop in vehicle height due to a drop in air temperature in the fluid chamber immediately after driving can be corrected 60 minutes after the ignition switch is turned off, but if the vehicle is left for a long time, the fluid pressure If there is even a slight leak in the equipment itself or in the connections with piping, it is impossible to correct the drop in vehicle height caused by the air leak, and there is no way to deal with such a drop in vehicle height. There was a point.

[Means for solving problems]

This invention' was made by paying attention to such conventional problems, and it is possible to increase or decrease the vehicle height by interposing the vehicle between the vehicle body and the wheels and adjusting the internal fluid pressure. a fluid chamber, a fluid pressure source that supplies fluid to the fluid chamber via an on-off valve, a vehicle height detector that outputs a detection signal according to the vehicle height, and a detected vehicle height value that is set as a first target vehicle height value. In the vehicle height control device, the vehicle height control device includes a controller that controls the fluid pressure source and the on-off valve to adjust the supply and discharge of fluid to the fluid chamber so as to match the fluid pressure source and the opening/closing valve. operation holding means for holding the vehicle height detector in an operable state when supply and discharge of fluid to and from the fluid chamber is stopped; The above-mentioned problem can be solved by providing a vehicle height determining means that sends a signal to the controller to restart the supply and discharge of fluid to the fluid chamber when the vehicle height falls below a second target vehicle height value that is lower than the target vehicle height value. The purpose is to resolve the issue.

[Effect]

Therefore, in the present invention, when the traveling drive device of the vehicle is in a stopped state and the supply and discharge of fluid to the fluid chamber interposed between the vehicle body and the wheels so as to be adjustable in vehicle height is stopped, The vehicle height detector is maintained in an operable state by the operation holding means, and the detected vehicle height value from the vehicle height detector is used as a reference for vehicle height adjustment when the traveling drive device is in the driving state. The vehicle height determination means determines whether or not the vehicle height has fallen below a second target vehicle height value, which is lower than the first target vehicle height value, and when the detected vehicle height value falls below the second target vehicle height value, the controller determines whether the fluid pressure The fluid is supplied to the fluid chamber by driving and controlling the source and the on-off valve, and in this way, control to raise the vehicle height is executed, and the system is activated only when vehicle height adjustment is necessary.

〔Example〕

The present invention will be explained below based on illustrated embodiments.

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

First, to explain the configuration, numeral 1 in the figure is a suspension unit (for example, for the front right wheel), which includes a shock absorber 2 whose expansion and contraction direction is set in the vertical direction, and a suspension unit that is provided above the shock absorber 2 and is made of rubber or the like. The fluid chamber 4 is defined by a shaped elastic body 3. The upper end portions of the piston rod 5 and rubber-like elastic body 3 of the shock absorber 2 are attached to the vehicle body 6, and the lower end portion of the shock absorber 2 is pivoted to a suspension arm 7 that is swingably supported by the vehicle body. The right wheel 8 is rotatably supported by the suspension arm 7, and in this way, the fluid chamber 4 is connected to the vehicle body 6 and the wheel 8.
The vehicle height can be increased or decreased between the vehicle and the vehicle.

The fluid chamber 4 is connected via a conduit 9 to a near compressor 10, which is a specific example of a fluid pressure source. This near compressor 10 has an electric motor 11 and an air pump 12 driven by the electric motor 11,
The high-pressure air discharged from the air pump 12 is supplied to an air supply/exhaust valve 1 which is an opening/closing valve inserted into the pipe line 9.
3 to the fluid chamber 4. Furthermore, the pipe line 9,
An exhaust valve 14, which is also an opening/closing valve, is connected upstream of the supply/exhaust valve 13. These supply/exhaust valves 13 and exhaust valves 14 each consist of a spring-offset/electromagnetic type two-point/two-position electromagnetic switching valve, and when the normal position is in a closed state, the output is output from a controller 15, which will be described later. Opening and closing are controlled based on control signals.

Furthermore, a vehicle height detector 16 that can be expanded and contracted in the vertical direction is inserted between the vehicle body 6 and the suspension arm 7.
The vehicle height is detected by measuring the relative position of the vehicle body 6 and the suspension arm 7 in the vertical direction. This vehicle height detector 16 is directly connected to a power source 17 such as a battery, and uses the power constantly supplied from the power source 17 to constantly detect the vehicle height and generate a vehicle height detection signal DH corresponding to the detected vehicle height value. It is output to the comparator 18.

Means for directly connecting the vehicle height detector 16 to the power source 17 is an engine (route in the figure), which is a specific example of a traveling drive device.
When the vehicle is stopped and supply and discharge of fluid to and from the fluid chamber 4 is stopped, the vehicle height detector 16 is configured as an operation holding means that maintains the vehicle height detector 16 in an operable state.

The comparator 18 compares the voltage corresponding to a preset second target vehicle height value H2 with the value of the vehicle height detection signal DH, and determines that the detected vehicle height value H is lower than the second target vehicle height value H2. At the same time, a signal as a result of the determination is sent to the electromagnetic coil 20a of the relay switch 20. The contact portion 20b of this relay switch 20 has one end connected to the controller 15.
The other end is connected to the off-side contact a of an ignition switch 21, which has two contacts a and b and is inserted between the controller 15 and the electric terminal a17.

When the ignition switch 21 is turned on to drive the engine, the on side contact a is selected and power is supplied directly from the power supply 17 to the controller 15, while when switched to the off side, the off side contact a is selected. is selected, and the controller 15 and power source 17 are indirectly connected via the controller 20.

Based on the signal from the vehicle height detector 16 and its own output signal, the controller 15 controls the electric motor 11 of the near compressor 10 and the air supply and exhaust gas, at least when electric power is supplied from the electric circuit on the relay switch 20 side. It has a function of supplying a drive current to the electromagnetic solenoid of the valve 13, opening the supply/exhaust valve 13, and supplying air from the near compressor 10 to the fluid chamber 4.

The comparator 18 and the relay switch 20 select a second target vehicle height value H that is lower than the first target vehicle height value H1.
This constitutes a specific example of a vehicle height determination means for determining whether the detected vehicle height H has fallen below the second target vehicle height H2, and closes the circuit and causes the controller 15 to Power is supplied from a power source 17. As a result, the controller 15 is activated, power is supplied from the controller 15 to the fluid pressure source 10 and the intake/exhaust valve 13, and the vehicle height adjustment to raise the vehicle height is executed.

Note that, apart from the vehicle height adjustment control when the ignition switch 21 is off according to the present invention, the controller 15 directly supplies power from the power source 17 to the controller 15 by selecting the on-side contact of the ignition switch 21. 15 and in a normal state where the engine is driven, the first target vehicle height value H1 is set in advance.
Based on this, when the detected vehicle height value H exceeds a predetermined appropriate vehicle height range (for example, H1±Δh, where Δh is the deviation value), the vehicle height is lowered and the detected vehicle height is When the vehicle height value H exceeds the appropriate vehicle height range to the lower side (H<Hl-
At Δh), normal vehicle height adjustment control is executed to raise the vehicle height.

Next, the effect will be explained.

Now, after the vehicle has stopped running, the ignition switch 21 is disconnected to stop the engine, and its off-side contact a is connected to the power source 17, and the controller 15
A relay switch 20 whose circuit is closed in the initial state is interposed between the power supply 17 and the power supply 17.
Since the power from 7 is not supplied to the controller 15, the controller 15 stops operating.

On the other hand, the vehicle height detector 16 is connected to the power supply 17 upstream of the ignition switch 21 and is constantly supplied with power, so even after the ignition switch 21 is turned off, the vehicle height cannot be detected. Then, the vehicle height detection signal DH is continuously sent to the comparator 18. The comparator 18 uses a detected vehicle speed value H based on the vehicle speed detection signal DH.
The voltage corresponding to the preset second target vehicle height value H
2, and when the detected vehicle speed value H is lower than the second target vehicle speed value H2 (H<H2), a control signal is sent to the relay switch 20.

In this case, due to the vehicle being left unused for a long period of time, the vehicle height may be lowered due to slight air leakage from fluid pressure devices such as the fluid chamber 4, supply and exhaust valves 13, and the pipes 9 that connect them. When the vehicle height value H falls below the second target vehicle height value H2,
A signal is output from the comparator 18, and the signal is supplied to the electromagnetic coil 20a of the relay switch 2. Therefore, the electromagnetic coil 2.Oa is excited, and its contact portion 20b
By closing, the controller 15 and the power source 17 are connected through the relay switch 20 and the ignition switch 21, and power from the power source 17 is supplied to the controller 15 through the on-side contact a and the contact portion 20b.

As a result, the controller 15 is activated, and drive current is supplied from the controller 15 to the electric motor 11 of the fluid pressure source 10 and the electromagnetic solenoid of the supply/exhaust valve 13, respectively. Therefore, the supply and exhaust valve 13 is opened, and the air pump 12 is driven in conjunction with the electric motor 11, and the high-pressure air produced thereby is pumped into the supply and exhaust pulp 13.
The fluid is supplied to the fluid chamber 4 of the suspension unit 1 through the. This increases the pressure within the fluid chamber 4, causing the rubber-like elastic body 3 to stretch upward and push up the vehicle body, thereby increasing the vehicle height.

Therefore, even after the vehicle stops running and the ignition switch 21 is turned off, if the vehicle height falls below the target vehicle height value due to air leakage, etc., the vehicle height detector 16, which is kept in an operable state by the operation holding means, Based on the operation of the vehicle height determination means that determines that the vehicle height has fallen below the target vehicle height value, the controller 15 is activated, and the fluid pressure source 10 and the intake and exhaust valves 13 are activated to execute vehicle height adjustment and adjust the actual vehicle height. Control is performed to match the target vehicle height value. Therefore, even if the vehicle is left unattended for a long period of time, the vehicle height is always maintained at a predetermined height, making it possible to reliably prevent interference between the underfloor of the vehicle and obstacles on the road surface. .

In particular, when the ignition switch 21 is off, power is not supplied to the comparator 15, but power is supplied to the vehicle height detector 16 and vehicle height determination means, and when vehicle height adjustment is required, power is supplied to the comparator 15. Since the vehicle is configured to perform vehicle height adjustment, the amount of power output from the power source 17 can be reduced, and waste of that power can be effectively suppressed.

2 and 3 show a second embodiment of the invention.

In this embodiment, as shown in FIG. 2, in addition to the vehicle height detector 16 in the previous embodiment, a vehicle height switch 30 is interposed between the vehicle body 6 and the suspension arm 7, and the ignition switch 21 is interposed between the vehicle body 6 and the suspension arm 7. After disconnecting the vehicle height switch 3
0, the vehicle height switch 30 detects a decrease in vehicle height, and activates the controller 15.

As shown in an enlarged cross-sectional view in FIG. 3, the vehicle height switch 30 includes a switch box 31, a piston-shaped upper electrode 32 slidably housed in a gap formed in the switch box 31, It has a plunger-shaped lower electrode 33 that penetrates the lower surface of the switch box 31 and is slidably provided so that its upper end faces the upper electrode 32, and the upper electrode 32 is suspended by a spring 34 so as to be movable up and down. This allows the suspension arm 1 to move up and down during driving.

The vehicle height switch 30 is rotatably supported by the vehicle body 6 at its upper end and by the suspension arm 7 at its other end. The upper electrode 32 is connected to the controller 15, the lower electrode 33 is connected to the off-side contact a of the ignition switch 21, and both electrodes 32.
33 approaches and the distance between them becomes less than a predetermined distance l, the vehicle height switch 30 is turned on and its circuit is connected.

The other configurations are the same as in the previous embodiment except for the comparator 18 and the relay switch 20, which have been discontinued, and by configuring in this way, it is possible to obtain the same effects as in the previous embodiment.

FIG. 4 shows a third embodiment of the invention.

In this embodiment, the controller 15 is composed of a microcomputer 40 and a power supply circuit 41 for the vehicle height adjustment system. The microcomputer 40 outputs a signal to the power supply circuit 4 to activate it, and determines whether or not to perform vehicle height adjustment based on the detected vehicle height value H.
1 to supply power to the fluid pressure source 10 etc. only when necessary.

The microcomputer 40 has an input/output port, a processing unit (CPU), a storage device such as a RAM, a ROM, and a timer, and has a vehicle height detection device connected to the input port via a sensor/power line 42. A vehicle height detection signal DH of the device 16 is supplied, and based on the detection signal, a control signal is output from the output side port to the electric motor 11, the supply/exhaust pulp 13, and the exhaust valve 14 via the power supply circuit 41.

In a normal state, this microcomputer 40 executes vehicle height control processing during general driving, such as rolling control performed based on vehicle height and vehicle speed, in accordance with a main program (not shown) stored in advance in a ROM of a storage device. do.

The microcomputer 40 executes the vehicle height control process during general driving, and at the same time executes the process, for example, every 100m5ec, as shown in FIGS. 5 and 6, which is stored in advance in the ROM of the storage device. The vehicle height adjustment process according to the present invention is executed according to the timer interrupt process.

That is, as shown in FIG. 5, first, in step ■,
It is determined whether an ignition switch (not shown) is in an off state. This determination can be made by checking whether power is being supplied from the ignition switch side. As a result of this determination, if the ignition switch is off and the engine is stopped, such as when the vehicle is stopped, the process moves to step (3) and starts a timer provided in the memory device. At the same time, the sensor/power line 42 connecting the controller 15 and the vehicle height detector 16 is turned off to cut off the power supply to the vehicle height detector 16.

Next, the process moves to step (2), and by counting and amplifying the timer, a predetermined value Δt set in advance is set in the timer. Next, the process moves to step (2), where it is determined whether the contents of the timer match any of a large number of time values (tl, t2, t3...tN) corresponding to a preset predetermined time. judge. As a result of the judgment, if the contents of the timer match any of the many time values,
Proceeding to step (3), the sensor/power line 42 is turned on to supply power to the vehicle height detector 16.

Next, the process proceeds to step (3), where the vehicle height detection signal DH of the vehicle height detector 16 is read, the vehicle height is calculated based on this, and the detected vehicle height value H is temporarily stored in a predetermined storage area of the storage device. .

Next, the process proceeds to step (2), where the detected vehicle height value H stored in step (2) is determined as the appropriate vehicle height obtained by subtracting a predetermined deviation value ΔH from the second target vehicle height value H2 previously stored in a predetermined storage area. A target upper limit value (H2+ΔH) that is larger than the target lower limit value (H2-ΔH) of the range (H2-ΔH=H2+ΔH) and is the second target vehicle height value H2 plus the deviation value ΔH.
Determine whether it is smaller than. As a result of that determination, H2
−Δl(<H<H2+ΔH when it is determined that
That is, the detected vehicle height value H is smaller than the target lower limit value H2−ΔH−, or the detected vehicle height value H is smaller than the target upper limit value H2+Δ
When it is larger than H, the process moves to step (2).

In step (2), by turning on the power supply circuit 41, power can be supplied to the electric motor 11 of the fluid pressure source 10, the electromagnetic solenoid of the supply/exhaust valve 13, and the electromagnetic solenoid of the exhaust pulp 14.

Next, the process moves to step (3) to execute vehicle height adjustment processing.

This vehicle height adjustment process has the configuration shown in FIG. 6. First, in step @, it is determined whether or not the detected vehicle height value H read in step (2) is smaller than the target lower limit value H2-ΔH. As a result of the determination, when the detected vehicle height value H is smaller than the target lower limit value H2-ΔH (H<H2-ΔH), that is, the vehicle height is within the appropriate vehicle height range (H2-ΔH%H2+ΔH)
If the current is being exceeded, the process moves to step 0, where a drive current is supplied to the electric motor 11 of the fluid pressure source 10 to start it, and an excitation current is supplied to the electromagnetic solenoid of the supply/exhaust valve 13. The lever pulp 13 is opened, and the high pressure air discharged from the air pump 12 is delivered to the fluid chamber 4 of the suspension unit 1 via the pipe 9 and the supply/exhaust valve 13.
to be introduced. As a result, the pressure inside the fluid chamber 4 increases,
Since the suspension unit 1 expands in response to the increase in pressure, the vehicle height is increased.

Next, the process moves to step 0 and a new detected vehicle height value Hne
- is read, and then the process moves to step @, where it is determined whether the new detected vehicle height value Hnew has become larger than the target lower limit value H2-ΔH. As a result of the determination, if the new detected vehicle height value Hnew is still smaller than the target lower limit value H2-ΔH, the process returns to step 0 and repeats the steps from step 0 until the determination result of step [phase] becomes Hnew > H2-ΔH. Repeat the @ process.

Also, the determination result of step [phase] is Hnew >H2-
When ΔH is reached, that is, when the new detected vehicle height value Hnew exceeds the target lower limit value H2−ΔH as a result of the vehicle height adjustment, the process moves to step [phase] and the electric motor 11
At the same time, the excitation current to the electromagnetic solenoid of the intake/exhaust valve 13 is cut off to close the intake/exhaust valve 13, thereby completing the vehicle height adjustment. Then move to step [phase].

On the other hand, in step @, the determination result is H<H2-
If the detected vehicle height value H is not ΔH, that is, if the detected vehicle height value H is greater than the target lower limit value H2−ΔH, the process proceeds to step O, and it is determined whether the detected vehicle height value H is greater than the target upper limit value H2+ΔH. do. As a result of the determination, if the detected vehicle height value H exceeds the target upper limit value H2+ΔH, the process moves to step [phase], and excitation current is supplied to each electromagnetic solenoid of the intake and exhaust valve 13 and the exhaust pulp 14 to It opens, and the air in the fluid chamber 4 is discharged from the exhaust valve 14 via the conduit 9 and the supply/exhaust valve 13, thereby contracting the fluid chamber 4 and lowering the vehicle height.

Next, the process moves to step [phase] and a new detected vehicle high value H
ne- is read, and then the process moves to step [phase], where it is determined whether the new detected vehicle height value Hnew has become smaller than the target upper limit value H2+ΔH. As a result of that judgment,
When the new detected vehicle height value Hnew is still larger than the target upper limit value H2+ΔH, the process returns to step [phase] and processes from step [phase] to step [phase] are performed until the determination result of step [phase] becomes Hnew <H2+ΔH. repeat.

Further, when the determination result of step [phase] is Hnew <H20ΔH, that is, as a result of vehicle height adjustment, vehicle height Hn
If e- is less than the target upper limit value H2+ΔH, the process moves to step
The excitation current to each electromagnetic solenoid No. 4 is cut off, both pulps 13 and 14 are closed, the vehicle height adjustment is completed, and the process moves to step [phase].

In step [phase], it is determined whether or not the ignition switch is on, and as a result of the determination, when the switch is in the on state, and as a result of the determination in step (2), the ignition switch is in the on state. sometimes,
This ends the interrupt processing and returns to the main program. However, if the determination result in step 0 is that the ignition switch is in the OFF state, the process moves to step (2) to turn off the power supply circuit 41 and cut off the power to the fluid pressure source 10, supply/exhaust valve 13, and exhaust valve 14. Then, return to step ■.

Further, in step (2), if the content of the timer does not match any of the multiple time values tl, t2...tN, and in step (2), the detected vehicle height H
is within the appropriate vehicle height range H2-ΔH-H2+ΔH, the process returns to step (2).

The processing of steps (1) to (2) above constitutes an operation holding means, and the processing of steps (2) to (3) constitutes a vehicle height determining means.

Next, the operation of this embodiment will be explained.

When the vehicle is stopped and the ignition switch is turned off to stop the engine, the ignition switch is determined to be in the OFF state in step ■, so the timer set in the memory device is activated in step ■. , and at the same time, the sensor/power line 42 is turned off. After counting and amplifying the timer in step (2), the process moves to step (2), where the contents of the timer are changed to a number of preset time values ti (i=1.2... ...N) is matched.

In this case, the processes of steps (2) and (2) are repeated until the contents of the timer match one of the time values ti, so that a preset predetermined time elapses. After this predetermined time has elapsed, the sensor/power line 4 is
2 is turned on. Therefore, the power supplied from the controller 15 to the vehicle height detector 16 is not continuously supplied all the time, but is supplied intermittently at necessary predetermined time intervals, so that unnecessary power is supplied to the vehicle height detector 16. without having to supply
Power consumption can be reduced.

In the next step ■, the vehicle height detector 160 vehicle height detection signal D
H is read, the detected vehicle height value H is calculated based on this, and the process proceeds to step (2), where it is determined whether the detected vehicle height value H is within the appropriate vehicle height range H2-ΔH-H2+ΔH.

At this time, the vehicle had been left unused for a long period of time, and a small air leak had occurred from equipment such as the fluid chamber 4 and supply/exhaust valve 13, or from the conduit 9 that connects them, so the vehicle height was adjusted to the appropriate vehicle height. If it is below the range, it is determined in step (2) that H2-ΔH(1)<H2+ΔH is not satisfied. Therefore, the process moves to step (2) and turns on the power supply circuit 41, thereby making it possible to supply power to the fluid pressure i10, the supply/exhaust valve 13, and the exhaust valve 14.

Next, move to step ■ and perform the step @ ~
Vehicle height adjustment is performed through the process of raising the vehicle height in step [phase]. After that, in step [phase], it is determined that the ignition switch is in the OFF state, so the interrupt processing is ended and the program returns to the main program.

Therefore, in this embodiment, power is not constantly supplied to the vehicle height detector 16, but power is supplied every necessary time to detect the vehicle height, and the vehicle height is detected based on the detected vehicle height value. Since it is determined whether or not to perform the height adjustment, unnecessary power is not supplied to the vehicle height detector 16, and power consumption can be effectively reduced.

In addition, in the above example, air was used as the fluid, but
It goes without saying that other gases may be used, and liquids such as oil and water may also be used.

〔Effect of the invention〕

As explained above, according to the present invention, fluid pressure is applied to the fluid chamber that is interposed between the vehicle body and the wheels and that can increase or decrease the vehicle height by adjusting the internal fluid pressure. At the same time, the vehicle height detection signal from the vehicle height detector is supplied to the controller that controls the fluid pressure source and the drive of the opening/closing valve. Based on the detected vehicle height value, the controller sets the detected vehicle height value to the first value. In a vehicle height control device that adjusts vehicle height by driving and controlling a fluid pressure source and an on-off valve to adjust the supply and discharge of fluid to a fluid chamber to match a target vehicle height value, there is a detector operating means for maintaining the vehicle height detector in an operable state when supply and discharge of fluid to and from the fluid chamber is stopped; and a vehicle height value detected from the vehicle height detector is a first target vehicle height value. The structure includes vehicle height determination means that sends a signal to the controller to resume supplying and discharging fluid to the fluid chamber when the vehicle height falls below a second target vehicle height value, which is lower than the second target vehicle height value. Vehicle height adjustment can be performed by supplying power to the vehicle height detector. Therefore, since the controller or vehicle height detector is activated only when necessary, unnecessary power is not supplied to the controller or vehicle height detector, resulting in a significant reduction in power wastage. It will be done. Moreover,
Even when the vehicle is left unused for a long period of time, the vehicle height is always maintained within the appropriate vehicle height range, which also has the effect of reliably preventing interference with road surface protrusions due to a decrease in vehicle height.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing one embodiment of the present invention, FIG. 2 is an explanatory diagram showing a second embodiment of the invention, FIG. 3 is an explanatory diagram of the vehicle height switch shown in FIG. FIG. 5 is an explanatory diagram showing a third embodiment of the present invention, FIG. 5 is a flowchart showing an example of a processing procedure of a controller according to the third embodiment, and FIG. 6 shows details of step (2) in FIG. It is a flowchart.

Claims (1)

[Claims] A fluid chamber that is interposed between the vehicle body and the wheels and that can increase or decrease the vehicle height by adjusting internal fluid pressure, and a fluid pressure source that supplies fluid to the fluid chamber via an on-off valve. a vehicle height detector that outputs a detection signal according to the vehicle height; and a vehicle height detector that controls driving and controlling the fluid pressure source and the opening/closing valve so that the detected vehicle height value matches a first target vehicle height value to supply fluid to the fluid chamber. a controller that adjusts the supply and discharge of the fluid to the fluid chamber; an operation holding means for holding the vehicle in an operable state, and a detected vehicle height value from the vehicle height detector is set to
further comprising: vehicle height determining means for transmitting a signal to the controller to restart supplying and discharging fluid to the fluid chamber when the vehicle height falls below a second target vehicle height value that is lower than the target vehicle height value of the vehicle height. Vehicle height control device.