JPS61184110A - Hydraulic suspension controller - Google Patents

Abstract

PURPOSE:To suppress rolling of body when getting on/off, in hydraulic suspension controller where second fluid chamber is communicated through open/close means to first fluid chamber arranged between the body and the wheel while regulatably of car height, by blocking the open/close means upon opening of door. CONSTITUTION:Under car height regulation control, a controller 12 will receive an output signal from a car height detector 13 and temporarily store as a car height detection level H. Then it is decided whether said level H is within preset referential car height region, and if the answer is NO, it is decided whether said level H is higher than said region. Supply/discharge of air against main air chamber 4 in suspension unit 1 is controlled in accordance to the decision results thus to regulate the car height. Upon detection of open door through a door opening condition detector 14, power is fed through an output circuit 15 to a relay 16 thus to close the contact and to switch a valve 11 to the operating position while to close a conduit 9 and to interrupt regulation of car height.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention allows the vehicle height to be increased or decreased by adjusting the pressure of the fluid chamber interposed between the vehicle body and the wheels, and the volume of the fluid chamber to be increased or decreased. The present invention relates to a fluid pressure suspension control device that can change a spring constant by changing the spring constant.

[Conventional technology]

As a conventional hydraulic suspension control device, there is, for example, one published in 5AE840342 (Journal of the American Society of Automotive Engineers).

This device consists of a 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, and a near hole that can supply high-pressure air to this fluid chamber. It has a fluid pressure source consisting of a compressor, an electric motor, etc., and an opening/closing pulp that is driven to open and close by a control signal supplied from a controller is interposed in a conduit that communicates these. The controller is connected to a vehicle height detector that detects the vehicle height, a door open/close state detector that detects the open/close state of the door, etc. Based on the detection signals of these detectors, the controller It repeatedly determines whether the height is within a predetermined range or not at very short predetermined intervals, and if the detected vehicle height is lower than a preset reference vehicle height, air is supplied to the fluid chamber to raise the vehicle height. let me, also,
When the detected vehicle height is higher than the reference vehicle height, air is discharged from the fluid chamber to lower the vehicle height.

[Problem that the invention seeks to solve] [However,
In such a conventional fluid pressure suspension control device, the controller drives the fluid pressure source and controls the opening/closing pulp based on the vehicle height detection signal from the vehicle height detector and the door state detection signal from the door opening/closing state detector. The system was configured to control the opening/closing operation and raise the vehicle height when the detected vehicle height was lower than the standard vehicle height, but since there was a delay in the rise of air pressure in the fluid chamber, the opening/exiting door could not be opened. If the driver gets on the vehicle immediately after riding the vehicle, there is a problem in that the load fluctuation during riding causes the vehicle body to roll significantly, impairing the ride comfort. In particular, if the vehicle height change due to the rolling occurs, for example, in a location where the sidewalk is one step higher than the road, the lower end of the door protruding outward from the vehicle body will collide with the curb.

[Means for solving problems]

This invention was made by focusing on such conventional problems, and as shown in the basic configuration diagram in Fig. 1, the present invention is a system that is interposed between the vehicle body and the wheels and adjusts the internal fluid pressure. In a fluid pressure suspension control device for a vehicle, a second fluid chamber is communicated with a first fluid chamber through an opening/closing means that is opened/closed in response to input of a control signal to increase or decrease the vehicle height. a door opening/closing state detector that outputs a detection signal according to the opening/closing state of the door; and a door opening/closing state detector that outputs the control signal to the opening/closing means at least when the door is opened based on the detection signal of the door opening/closing state detector; It is an object of the present invention to solve the above-mentioned problems by configuring a fluid pressure suspension control device including: a control means for isolating between the fluid chamber and the second fluid chamber.

[Effect]

According to the present invention, the open/closed state of the door for getting on and off, etc. is detected by the door open/closed state detector, and the detection signal is supplied to the control means, and based on the detection signal, at least when the door is opened, the control is performed. By closing the opening/closing means in response to a control signal from the means and isolating the first fluid chamber and the fluid chamber i2, the spring constant of the fluid pressure suspension device can be adjusted to Switching to the hard side using only the fluid pressure in the first fluid chamber, which allows vehicle height adjustment, suppresses rolling and pitching of the vehicle body due to load fluctuations when getting on and off.

〔Example〕

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

1 to 4 are diagrams showing one embodiment of the present invention.

First, to explain the configuration, 1 shown in FIG. 2 is, for example,
This is a suspension device for the front right wheel, and this suspension device 1 includes a shock absorber 2 whose expansion and contraction direction is set in the vertical direction, and a rubber-like elastic body 3 such as rubber that is provided above the shock absorber 2. The main air chamber 4 is an integrated example of the first fluid chamber. The piston rod 5 and the upper end of the rubber-like elastic body 3 of the shock absorber 2 are attached to the vehicle body 6, and the lower end of the shock absorber 2 is pivoted to a suspension arm 7 that is swingably supported by the vehicle body 6. A right wheel 8 is rotatably supported by the suspension arm 7, and in this way, the hydraulic suspension device 1 is interposed between the vehicle body 6 and the wheel 8.

The main air chamber 4 is communicated via a conduit 9 to an auxiliary air chamber 10, which is a specific example of a second fluid chamber. and,
These air chambers 4 and 1O are communicated with a near compressor and a reservoir tank (not shown) that constitute a fluid pressure source, and air at a predetermined pressure produced by the near compressor is supplied to these air chambers 4 and 10 via the reservoir tank. Supplied.

Furthermore, an opening/closing pulp 11 consisting of a spring-offset electromagnetic type electromagnetic switching valve is inserted into the pipe line 9. The opening/closing pulp 11 is in a communication state in its normal position, and is held in its normal position by a control signal with a logic value of "0" output from a controller 12, which will be described later, and its electromagnetic position is maintained by a control signal with a logic value of "1". The solenoid is energized and switched to an operative position where it blocks line 9. The opening/closing valve 11 constitutes an example of an opening/closing means.

A vehicle height detector 13 and a door opening/closing state detector 14 are connected to the controller 12 . The vehicle height detector 13 is configured by, for example, an ultrasonic distance measuring device that is attached to the lower surface of the vehicle body 6 and outputs a vehicle height detection signal DH corresponding to the height from the mounting position to the road surface. Further, the door open/close state detector 14 is constituted by, for example, a door lock switch, and outputs a signal with a logical value of "1" when the door is in the locked state, while outputting a signal with a logical value of "1" when the door is in the unlocked state. A door state detection signal DD with a value of "0'" is output.

The controller 12 to which each detection signal of these detectors 13 and 14 is supplied is an input/output port processing unit (CPt
J) It has a microcomputer equipped with a storage device such as RAM, ROM, etc., and its input side board receives the vehicle height detection signal DH of the vehicle height detector 13 and the door opening/closing state detector 14.
A door state detection signal DD is supplied to the microcomputer, and based on these input signals and its own output signal, the microcomputer outputs a logic value "1" or a logic value "
A control signal of 0'' is output to the output circuit 15.

The output circuit 15 receiving this control signal outputs an excitation current to the drive relay 16 to drive it, and closes the circuit to set a predetermined value when the control signal has a logical value of "1". A driving current is supplied from the power source 17 to the on-off valve 11.
energizes the electromagnetic solenoid. As a result, the on-off valve 11 is switched from the normal position to the operating position, the conduit 9 is closed, and the connection between the main air chamber 4 and the auxiliary air chamber IO is cut off.

The microcomputer executes normal vehicle height adjustment control to increase or decrease the vehicle height based on the vehicle height detection value according to the main program shown in FIG. 3, which is stored in advance in the ROM of the storage device.

That is, first, initial settings are executed in step (2), and then the process proceeds to step (2), where the vehicle height detection signal DH of the vehicle height detector 13 is read, and the vehicle height of the attachment portion of the suspension device 1 is calculated based on this. Then, it is temporarily stored as a vehicle height detection value H in a predetermined storage area of the RAM of the storage device.

Next, the process proceeds to step (2), where the vehicle height detection value H stored in step (2) is read out, and the vehicle height detection value H is set in a predetermined width ΔH within a vehicle height reference range Ho≦H<Ho+Δ
It is determined whether or not it is within H. Therefore, when the vehicle height detection value H is within the vehicle height reference region Ho≦H<Ho+ΔH, the process returns to step (2), whereas when the vehicle height detection value H is not within the vehicle height reference region Ho≦H<Ho+ΔH, the process returns to step Move to ■.

In this step ■, the vehicle height detection value H is set to the vehicle height reference area Ho.
It is determined whether or not ≦H<Ho+ΔH, and when the result of the determination is H<Ho, it is determined that the vehicle height is low and the process moves to step (2), and the result of the determination is H>Ho
When it is 10ΔH, it is determined that the vehicle height is high and the process moves to step (2).

In step (3) above, the vehicle height is increased by controlling the opening and closing of the on-off valve (not shown), and as a result, the air produced by the near compressor (not shown) and stored in the reservoir tank is pumped into the main air chamber 4. As a result, the main air chamber 4 expands in the vertical direction, increasing the vehicle height. In addition, in step (2), the opening/closing valve is controlled to lower the vehicle height, and as a result, air is discharged from the main air chamber 4 to the atmosphere, and as a result, the main air chamber 4 contracts. Vehicle height is lowered.

While executing the main program, this microcomputer also executes the timer interrupt processing program according to the present invention shown in FIG. 4, which is prestored in the ROM of the storage device.

This interrupt processing first reads the door state detection signal DD from the door open/closed state detector 14 and stores it in a predetermined storage area of the storage device at step [share].

Next, the process proceeds to step (3), where it is determined whether the vehicle's entrance/exit door is in an open state. In this case, the judgment is whether the door state detection signal DD is a logical value “1” or a logical value “0”.
This is done by checking whether Here, when the door is in a closed state, the interrupt process is ended and the program returns to the main program, but when the door is in an open state, the process moves to step @.

In step [phase], a control signal with a logical value of "1" is output to the output circuit 15, thereby supplying an excitation current to the drive relay 16. As a result, the electromagnetic opening/closing valve 11 A predetermined driving current from the power source 17 is supplied to the solenoid, thereby switching the on-off valve 11 to the operating position and closing the conduit 9. This completes the interrupt processing and returns to the main program.

The processing of steps [phase] to step @ above constitutes a control means.

The door may be of a type in which one side is rotatably supported toward the vehicle body by a hinge and the other side is pivoted, or it may be a door that is slid along the vehicle body.

Next, the effect will be explained.

Assuming that the vehicle is now in a parked state, when the processing program shown in FIG. Then, the process moves to step (2), and it is determined whether the door for getting on and off is opened based on the door state detection signal DD read in step [phase].

At this time, for example, when a person opens the door to board the vehicle,
Since the logical value of the door state detection signal DD output in accordance with the open/closed state of the door becomes "1", it is determined in step (2) that the door is in the open state. Therefore, the process moves to step @, and a control signal with a logical value of "1" for closing the on-off valve 11 is output to the output circuit 15.

In this way, when a control signal with a logical value of "1" is supplied to the output circuit 15, the output circuit 15 outputs an exciting current to the drive relay 16, which closes the drive relay 16 and closes the opening/closing valve 11. A predetermined drive current is supplied to the electromagnetic solenoid. As a result, the on-off valve 11 is switched to the operating position, so the conduit 9 is closed and communication between the main air chamber 4 and the auxiliary air chamber 10 is cut off.

As a result, the volume of the fluid chamber that determines the spring constant of this fluid pressure suspension device 1 changes from the volume of the main air chamber 4 plus the volume of the auxiliary air chamber 10 to the volume of the main air chamber 4 alone. , the spring constant increases (hard state) due to the decrease in volume. Therefore, when a person gets on the vehicle in this state, the spring constant of the suspension device is set to the stiff side, and the vehicle body is affected by the load fluctuation caused by the person getting on the vehicle, compared to a case where the spring constant is set to the soft side. The occurrence of rolling, pitching, etc. can be suppressed.

Therefore, it is possible to reduce changes in vehicle height caused by people getting on and off the vehicle, thereby improving the ride comfort of the vehicle when getting on and off the vehicle. In particular, for example, when the height of the sidewalk is one step higher than the height of the road, even if the door protrudes outward from the vehicle body, the lower end of the door may change due to changes in vehicle height when getting on the vehicle. It can prevent you from colliding with a curb.

In the above embodiment, a case has been described in which the suspension device for the front right wheel is controlled, but the configurations of the other suspension devices are also similar to the suspension device 1, and are controlled in the same manner as described above. In addition, the controller is not limited to the above configuration,
It can also be constructed from electronic circuits such as comparison circuits and logic circuits.

Further, the door opening/closing state detector may be a touch switch provided on the handle of the door. At least when the door is opened includes not only the time when the door is actually opened by a predetermined amount and the time when the door starts to be opened, but also the stage immediately after the door lock is released before the door is opened. Furthermore, it goes without saying that the configuration of the on-off valve 11 is not limited to the above embodiment. Although air was used as the working fluid in the above embodiment,
It goes without saying that other gases may be used, and even a hydropneumatic suspension that uses a gas spring and a liquid such as oil or water is also applicable.

〔Effect of the invention〕

As explained above, according to the present invention, the first fluid chamber interposed between the vehicle body and the wheels so as to be able to adjust the vehicle height;
The second
A fluid pressure suspension control device that communicates with a fluid chamber includes a door opening/closing state detector for detecting the opening/closing state of the door, and a control means for controlling opening/closing of the opening/closing means, and at least when the door is opened, the opening/closing means is operated. Activate the first
The structure is such that the fluid chamber is isolated from the second fluid chamber.

Therefore, when the door is opened for the purpose of getting on or off the vehicle, the spring constant of the fluid pressure suspension device can be set to a larger (harder) side almost at the same time. Shaking of the vehicle body due to load fluctuations at that time can be effectively suppressed. Therefore,
The effect of improving the riding comfort of the vehicle when getting on and off the vehicle can be obtained. In particular, if the door is of a type that protrudes outward from the vehicle body when opened, for example, even if you open the door carelessly and get into the vehicle at a location with a protrusion such as a curb, the fluid pressure will be reduced immediately after the door is opened. Since the spring constant of the suspension device is set on the stiff side, it is possible to suppress the door from colliding with a curb or the like, and there is also the effect that damage to the vehicle due to such load fluctuations can be prevented.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic configuration of the present invention, FIG. 2 is a system explanatory diagram showing an embodiment of the invention, FIG. 3 is a flowchart showing an example of the processing procedure of normal vehicle height adjustment control, and FIG. FIG. 4 is a flowchart showing an example of the processing procedure of the control device according to the present invention. 1...Fluid pressure suspension device, 2...
... Shock absorber, 3 ... Rubber-like elastic body, 4 ... Main air chamber (first fluid chamber), 6 ...
... Vehicle body, 7 ... Suspension arm, 8
...Wheel, 9...Pipe line, 10...
... Auxiliary air chamber (second fluid chamber), 11... Opening/closing valve (opening/closing means), 12... Controller, 13... Vehicle height detector, 14... ...Door open/close status detector

Claims (1)

[Claims] A first fluid chamber, which is interposed between the vehicle body and the wheels and is capable of increasing or decreasing the vehicle height by adjusting internal fluid pressure, is connected to a second fluid chamber through an opening/closing means that is opened and closed by inputting a control signal. A fluid pressure suspension control device for a vehicle that communicates a fluid chamber with a door opening/closing state detector that outputs a detection signal according to the opening/closing state of a door of the vehicle, and a door opening/closing state detector that outputs a detection signal according to the opening/closing state of a door of the vehicle; A fluid pressure suspension control device comprising: a control means that outputs the control signal to the opening/closing means to cut off a connection between the first fluid chamber and the second fluid chamber when the opening/closing means is opened. .