JPS624620A - Suspension device for automobile - Google Patents

Abstract

PURPOSE:To automize the diagonal control with the provision of its positive function by configurating a device in such a way that a wheel which looses traction, is detected by a stuck wheel detecting means which is newly provided, so as to effect the control for the restoration of traction. CONSTITUTION:Signals detected by ground clearance detectors 37a-37d are inputted into a controller 20. While the condition of running is being detected (36), the amount of rebound for each of wheels is computed on the basis of the said signals. And a wheel is judged to be stuck when the amount of rebound beyond the specified one has kept continuing beyond the specified period of time set by a timer 35. Resultantly, a wheel which looses traction, for example if it is a right front wheel 'b', allows both change-over valves 12 and 13 and a tank closing valve 15 to be opened permitting a compressor 2 to be operated. Subsequently, this causes a buzzer 32 to sound, a lamp 33 to go on and off, and the function of the diagonal control to be effected with actuators 22 and 23 extended. The controller 20 allows ground clearance to be restored to its initial condition just after the diagonal control has been completed. Thus, this configuration allows the diagonal control to be automized with the provision of its positive function.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an automobile suspension device having a vehicle height adjustment function.

(Prior Art) Although it is desirable for the vehicle height of an automobile to be low in terms of running stability, if the vehicle height is too low, there is a risk that the lower surface of the vehicle body may come into contact with the ground when driving on a bumpy road. For this reason, as disclosed in Japanese Patent Application Laid-Open No. 58-30809, various driving conditions are detected by sensors,
A vehicle height control method has been proposed that prevents damage to the vehicle body by controlling the suspension to lower the vehicle body on good roads and raise the vehicle body on bad roads.

Further, when a car is traveling on an uneven road surface and one wheel falls into a recess on the road surface, for example, if the left front wheel a falls into the recess as shown in FIG. The right rear wheel d, which is located on the diagonal line of the left front wheel a with respect to the axis X-x connecting the right front wheel and the left rear wheel C, lifts up or the ground load becomes small at the 8i end. Therefore, when this wheel d is a driving wheel, the wheel d spins idle and does not generate enough driving force or traction force to push the front wheel a out of the recess on the road surface, making it impossible to escape from the recess. It becomes possible.

Also, when a four-wheel drive vehicle is driving on snow or sand, I! Due to the difference in jm resistance, one of the drive wheels may dig into snow or sand on the road surface.

Now, assuming that the left front wheel a shown in FIG. The center lifts up or the ground load becomes small, causing the wheel to spin idly, and as a result, the left front wheel a cannot escape from the recess it has dug itself.

In view of this, the present applicant has filed patent application No. 58-1922.
A condition in which one of the four wheels in No. 46 becomes stuck due to falling into a recess or digging into snow or sand (hereinafter, this condition is referred to as a stuck condition)
If this happens, the vehicle height of only the suspension that supports the stuck wheel and the wheels located diagonally to this wheel is increased, and the stuck wheel and the wheels located diagonally to this We are proposing a suspension device that increases the ground contact load of the wheels that cause the vehicle to get stuck. Hereinafter, such vehicle height control will be referred to as diagonal control.

When using the suspension device proposed above, when a vehicle gets stuck, it is necessary to check which wheel has lost traction and raise the vehicle height of the part of the wheel that has lost traction. However, in this case, there is a problem in that when a vehicle gets stuck, the occupants and the like must check which wheel is losing traction each time, which is cumbersome.

(Object of the Invention) In view of such problems, the present invention automatically detects the position of the wheel losing traction when the wheel becomes stuck, and automatically performs diagonal control based on this detection. The object of the present invention is to provide a suspension device for an automobile that can perform the following steps.

(Structure of the Invention) The suspension device of the present invention includes a fluid actuator that is expandable and retractable by supplying and discharging pressurized fluid to a variable volume fluid chamber.
It is arranged between a support member that supports the wheels and the vehicle body, and allows pressurized fluid generated by a pump means such as an oil pump or a compressor to be supplied and discharged to the fluid chamber through the switching valve, and when one of the wheels When the vehicle is stuck due to loss of traction, the control means controls the operation of the switching valve, which is disposed between the wheel losing traction and/or a wheel located diagonally therefrom and the vehicle body. supplying pressurized fluid to the fluid chamber of a fluid actuator that has been installed, or discharging pressurized fluid from the fluid chamber of a fluid actuator that is disposed between the vehicle body and the wheel located on a diagonal line that intersects the diagonal line above. This feature is characterized in that it is made easier to escape from a stuck state by restoring 1 to lux.

(Embodiments) Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a pneumatic circuit diagram of a suspension device according to an embodiment of the present invention. A compressor 2 driven by a motor 1 pressurizes air and sends it out to a passage L1, and this pressurized air is sent to a passage L2 via a dryer 3 and a check valve 4.

The first to third pressure switches 5.6.7 are connected to the passage L2, and the first to fourth switching valves 11 to 14 and the tank opening/closing valve 15 are connected to the passage L2.

The first to fourth switching valves 11 to 14 are opened and closed by the operation of solenoids 118 to 14a, respectively, and thereby communicate and cut off the passage L2 and the passages 4 to L7. The passages L4 to L7 communicate with the variable volume fluid chambers of the first to fourth actuators 21 to 24, which are disposed between the vehicle body and the support member that supports each wheel, and are connected to the variable volume fluid chambers of the first to fourth actuators 21 to 24, respectively, and are connected to the variable volume fluid chambers of the first to fourth actuators 21 to 24, respectively. Fourth switching valve 11
Pressurized air is supplied to and discharged from the fluid chamber in accordance with the opening and closing operations of the actuators 21 to 14, and the fluid actuators 21 to 24 expand and contract. The tank opening/closing valve 15 is opened and closed by the operation of the solenoid 15a, and by opening the tank opening/closing valve 15, the pressurized air sent to the passage L2 is stored in the reserve tank via the passage L3. Switching valves 21 to 24
When opened, the stored pressurized air is sent out to the fluid chambers of the fluid actuators 21-24. A relief valve 9 is provided in the passage L3 to prevent the air pressure in the reserve tank 10 from exceeding the maximum allowable pressure. In general, a fourth pressure detection switch 8 is connected to the reserve tank 10 to detect the pressure inside the reserve tank. Note that an exhaust opening/closing valve 16 operated by a solenoid 16a communicates with the passage L1 communicating with the outlet side of the compressor 2, and by opening this valve 16, the air in the fluid chambers of the fluid actuators 21 to 24 is released. It is now possible to discharge and retract the fluid actuators 21-24.

FIG. 2 is a control circuit diagram for controlling the operation of the pneumatic circuit diagram shown in FIG. 1. This control is performed by controller 2.
0 to the first to fourth switching valves 11 to 14 via lines 21 to 24, lines 25 and 2.
6 to the tank opening/closing valve 15 and the exhaust opening/closing valve 16, these valves 11
- 16 are operated, supplying and discharging pressurized air to the fluid chambers of the first to fourth fluid actuators 21 to 24 arranged between each wheel a to d and the vehicle body, and pressurizing the reserve tank 10. Air is supplied and discharged, and the passage L2 is communicated with and cut off from the atmosphere. Further, a control signal sent from the controller 20 to the compressor 2 via a line 27 causes the compressor 2 to operate υll1l. The controller 20 receives detection signals from the first to fourth pressure detection switches 5 to 8 via lines 5a to 8a, detection signals from an engine operation detection sensor 31 via a line 31a, and a detection signal from the engine operation detection sensor 31 via a line 34a. An input signal from the high switching manual switch 34, an input signal from the timer 35 via line 35a, an input signal from the running state detection means 36 via line 36a, and an input signal from each wheel a to e via line 37a.
Vehicle height sensor 37 that detects the vehicle height of the suspension section of
Input signals from a to 37d are input. The manual switch 34 adjusts the vehicle height, and when an input signal is input from this switch, the operation of each valve and the compressor 2 is controlled to adjust the vehicle height, and at the same time, the buzzer 32 generates a warning sound if necessary. and an indicator 33 displays. On the other hand, when the car is stuck, the controller 20 detects the wheel that has lost traction based on the signals from the vehicle height sensors 37a to 37d, and controls each valve and the controller 20 to restore the traction of the wheel. The operation of the compressor 2 is automatically controlled.

Such operation control will be explained using FIG. 1 J5 and FIG. 2 together. First, vehicle height adjustment will be explained. According to this device, the manual switch 34 is
The vehicle height can be adjusted using the H'' button, but this adjustment is only possible when the vehicle is stopped, and the HIGH, LOW
Only two-stage switching is possible. Further, this device can only operate when the engine operation detection sensor 31 detects that the engine is operating.

To raise the vehicle height, press #HT of manual switch 34.
*Press the button to turn it on. This allows the first
~The fourth switching valves 11 to 14 are opened, the compressor 2 is driven by the motor 1, and at the same time the tank opening/closing valve 15 is opened.
opens. At this time, the "H" lamp of the indicator 33 flashes, and the buzzer 32 emits a warning sound.As a result, the compressed air in the reserve tank 10 and the compressed air from the compressor 2 are supplied, and the fluid actuators 21 to 2
4 is extended and the vehicle height is raised. The tank opening/closing valve 15 closes 10 seconds after opening, and the internal pressure of the passage L2 (this is equal to the fluid chamber pressure of the fluid actuator) is 6.8 kg/ci.
At this time, the east 1 pressure detection switch 5 is turned on, thereby closing the third and fourth switching valves 13 and 14. Then, the internal pressure of passage L2 is 7,8 Kg/cr.
When the pressure reaches i, the second pressure detection switch 6 turns on, and ■i
1 J5 and 2nd switching valve 1 after determining that up is complete.
1.12 is closed, the operation J3 of the compressor 2 and the warning from the buzzer 32 are stopped, and the indicator 33 lights up the ゛H parameter. Note that even if the first and second pressure detection switches 5.6 are turned off after this, the system does not restart.

To lower the vehicle height, press the manual switch 34 “HII”.
Press the button to turn it off. This allows the first
~Fourth switching valves 11 to 14 and exhaust opening/closing valve 1
6 opens, and the air in the fluid chambers of the fluid actuators 21 to 24 is discharged.

When the "1-1" button is turned OFF, the "H" lamp of the indicator 33 starts, and the buzzer 32 emits a warning sound. After 45 seconds have passed after the IN H11 button is turned OFF, it is determined that the vehicle height has been lowered. Then, all of the above-mentioned valves are closed, the indicator 33 is turned off, and the buzzer 32 is deactivated.

In addition, since it is necessary to always store a predetermined amount of pressurized air in the reserve tank 10, the fourth pressure detection switch 8 is turned OFF and the tank internal pressure is below the standard (9.0K in this example).
Fi/ci), the tank opening/closing valve 15
is opened and the compressor 2 is operated to send pressurized air into the tank to maintain the tank internal pressure above the standard.

Next, diagonal control will be explained.

First, a description will be given of a case where the vehicle gets stuck while driving with the vehicle height at LOW. At this time, it detects which wheel is losing traction.
This detection is performed by vehicle height sensors 37a to 37d.

A wheel loses 1 traction when the wheel falls into a recess, so when the rebound Q of the wheel exceeds a predetermined value, the wheel that has lost 1 traction can be determined by detecting a rebound range of more than the predetermined value. To detect. However, if the rebound is only temporarily exceeded while driving, it is not a stuck state, so the timer 35 detects the duration of the rebound state for more than a predetermined time and indicates that the rebound state continues for more than a predetermined time. A stuck state is detected only when the Furthermore, when the vehicle is stopped and the vehicle is to be lifted up by 1ν to repair a puncture, for example, the rebound state will continue by a predetermined amount or more.
Based on the detection of the engagement state of the transmission gear and the connection state of the clutch in step 6, this is performed only when the vehicle is in a running state. As a result of this detection, if it is detected that the front wheel on the G side is losing traction, for example, the second and third switching valves 12 and 13 and the tank opening/closing valve 15 are activated based on the control signal from the controller 20. It is opened and compressor Fj2 is operated. At this time, the buzzer 32 starts generating a warning sound and the indicator 33 starts blinking the R11 lamp. As a result, the second and third fluid actuators 22
．． Pressurized air is supplied to the fluid chamber 23, and the seven cutout units 22, 23 are extended.

As a result, the internal pressure in the passage L2 and the reserve tank 10 also increases, and the first and second pressure detection switches 5 and 6 are set to 6, 8 Kg/cti, 7, and 8 K, respectively.
It turns on at a pressure of g/ci, and then the fourth pressure detection switch 8 turns on at a pressure of 9.0 g/ci. This pressure increases in proportion to the ground load of the wheel, and when the pressure reaches the point at which the fourth pressure detection switch 8 turns ON, the ground load of the wheel to which the actuator 22, 23 is attached is sufficient. It is determined that the diagonal control is completed, and each valve is closed, the RII clamp of the indicator 33 is lit, and the buzzer 32 is turned on.
The warning sound continues. When the stuck state is released by this diagonal control, the controller 20 sends an operation control signal to each valve etc. so as to perform the same operation as lowering the vehicle height described above, thereby returning the vehicle height to its original state. Note that the warning sound from the buzzer 32 continues during this period, and stops only when the diagonal control is completed and the vehicle height has been lowered to its original state.

Next, a description will be given of a case where the vehicle gets stuck while driving with the vehicle height at HIGH. At this time as well, the front wheel that is losing traction is detected by the signal from the vehicle height sensor E, etc., and if this is the right front wheel, for example, then the 163rd and 4th switching valves 11.14 Then, the exhaust opening/closing valve 16 is opened, the buzzer 32 starts sounding, and the "R" lamp of the indicator 33 starts flashing.As a result, the pressurized air in the fluid chambers of the first iJ3 and the fourth fluid actuator 21, 24 is discharged and this actuator 21.24 retracts.On the other hand, the second and third fluid actuators 21.23 attached to the wheels that have lost traction remain as they are, so that the ground load of the wheel that has lost traction is reduced. When 45 seconds have elapsed after the start of diagonal control, the main operation is judged to have been completed, the opened valve is closed, and the "'R" lamp of the indicator 33 lights up. However, the buzzer 32 continues to sound. After this, when the vehicle escapes from the stuck state, the vehicle height is raised in the vehicle height adjustment based on the control signal from the controller 20, the vehicle height returns to the original state, and at this point the buzzer 32 stops operating. .

Note that the third pressure detection switch 7 detects the specified minimum pressure, (0,
6/m), and when the ignition is turned on, the "H" button of the manual switch 33 is turned OFF.
When F, open the first to fourth switching valves 11 to 14,
Detect whether the pressure at this time is above 0.6 Kg/cm, and if it is below 0.6 to 9/ci, operate the compressor 2 to reduce this pressure to 0.6 to 9/ci.

In the above example, air is used as the working fluid, but it is a matter of heat theory that water, oil, etc. may be used instead of air.

(Effects of the Invention) As explained above, according to the present invention, by detecting the vehicle height at the mounting portion of each wheel, a wheel losing traction in a stuck state is detected, and based on this detection signal, each wheel Controls supply and discharge of overpressure fluid to the fluid chamber of a fluid actuator disposed between the support member supporting the vehicle and the vehicle body, and controls the supply and discharge of overpressure fluid to the fluid chamber of the fluid actuator that supports the wheel and/or the wheel located diagonally thereto. Diagonal control, which increases the ground contact load, is automatically performed, so in the event of a stuck condition, the occupants have to check the wheel that is losing traction each time, and manually perform diagonal control. This eliminates the need for operation, making the operation more convenient and allowing for more reliable diagonal control.

[Brief explanation of the drawing]

Fig. 1 is a pneumatic circuit diagram of a suspension device according to the present invention, Fig. 2 is a control circuit diagram for controlling the operation of the above pneumatic circuit diagram, and Fig. 3 is a schematic plan view of an automobile to show the conventional problems. It is a diagram. 2...Complete tree' 5-8...Pressure detection switch 10...Reserve tank 11...Switching valve 15...Tank opening/closing valve 1
6...Exhaust on/off valves 21-24...Controller 32...Buzzer 33...Indicator 34
・・・Manual switch

Claims (1)

[Scope of Claims] 1) A fluid actuator that has a variable volume fluid chamber, is expandable and retractable by supplying and discharging pressurized fluid to the fluid chamber, and is disposed between a support member that supports wheels and a vehicle body; , a pump means for generating the pressurized fluid; a switching valve for disconnecting and disconnecting the pump means from the fluid actuator and supplying and discharging the pressurized fluid to the fluid chamber; and one of the wheels. When the vehicle is stuck due to loss of traction, the fluid enters the fluid chamber of the fluid actuator, which is disposed between the vehicle body and the wheel that has lost traction and/or a wheel located diagonally to the wheel. Traction is restored by supplying pressurized fluid or discharging the pressurized fluid from a fluid chamber of the fluid actuator disposed between the vehicle body and a wheel located on a diagonal line intersecting the diagonal line. and a control means for controlling the operation of the switching valve, and a stuck wheel detection means for detecting a wheel losing traction in response to the output of the vehicle height sensor, and based on a signal from the detection means. A suspension device for an automobile, characterized in that the control means automatically performs control for traction recovery. 2) The stuck wheel detection means determines that the fluid actuator is stuck when a rebound state of a predetermined value or more continues for a predetermined time or more, and issues a signal to the control means. An automobile suspension device according to claim 1. 3) The stuck wheel detection means detects the stuck state only when the vehicle is running.
Suspension devices for automobiles listed in Section.