JPH0249923B2 - SHARYOYOSASUPENSHONSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle suspension device that prevents rolling of an automobile.

Conventionally, as shown in U.S. Pat. No. 2,950,124, for example, fluid spring chambers are arranged on the left and right sides of a vehicle, and when the vehicle is turning, fluid is supplied to the fluid spring chambers on the outside of the turn, and fluid is supplied to the fluid spring chambers on the inside of the turn. 2. Description of the Related Art Suspension devices are known that have a roll control function that reduces roll of a vehicle body by discharging fluid from a chamber. In order to obtain sufficient effects of roll control in this device, it is necessary to set the flow rate per unit time of the fluid supplied and discharged into the fluid spring chamber to a certain degree during roll control.

Therefore, when this type of device is configured to be able to adjust the vehicle height, if the fluid in the fluid spring chamber is supplied and discharged via the fluid supply and discharge path used during the roll control, the vehicle height will be adjusted. The problem was that the vehicle was too fast and the vehicle height overshot and could not be set to the target vehicle height.

This invention was made in view of the above points,
The purpose of this system is to create a vehicle suspension system that eliminates the drawbacks of the conventional systems described above by varying the flow rate per unit time of the fluid supplied and discharged into the fluid spring chamber during vehicle body posture control and vehicle height adjustment. It is about providing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An electronically controlled suspension device according to an embodiment of the present invention will be described below with reference to the drawings. In the diagram, S _FR indicates the suspension unit for the right front wheel of the automobile, S _FL indicates the suspension unit for the left front wheel, S _RR indicates the suspension unit for the right rear wheel, and S _RL indicates the suspension unit for the left rear wheel. . The above suspension units S _FR , S _FL , S _RR , and S _RL are the main air spring chamber 1, respectively.
1a to 11d, auxiliary air spring chambers 12a to 12d, shock absorbers 13a to 13d, and a coil spring (not shown) used as an auxiliary spring. Furthermore, 14 is a compressor.
The compressor 14 compresses atmospheric air sent from an air cleaner (not shown) and supplies it to the reserve tank 17 via a check valve 15 and a dryer 16.

In addition, the compressed air stored in the reserve tank 17 is supplied to the pipe A and the air supply solenoid valve 18.
a to the main air spring chamber 11a, via piping A and the air supply solenoid valve 18b to the main air spring chamber 11b, and via piping A and the air supply solenoid valve 18c to the main air spring chamber 11c.
Then, the air is supplied to the main air spring chamber 11d via the piping A and the air supply solenoid valve 18d. Here, the air supply solenoid valves 18a to 18
d is the same, and its detailed configuration will be described later with reference to FIG.

Further, the compressed air in the main air spring chambers 11a to 11d is supplied to exhaust solenoid valves 19a to 19d,
Exhaust flow rate restriction solenoid valve 20, exhaust pipe 2
1 to the atmosphere. Here, the detailed structure of the exhaust flow rate control solenoid valve 20 will be described later using FIG. 3.

Further, the main air spring chambers 11a and 11b are connected via a communication solenoid valve 22a, a communication pipe B, and a communication solenoid valve 22b. The communication solenoid valve 22a also controls communication and isolation between the main air spring chamber 11a and the auxiliary air spring chamber 12a. Similarly, the communication solenoid valve 22b is connected to the main air spring chamber 11b.
It also controls communication and isolation between the air spring chamber 12b and the auxiliary air spring chamber 12b. Further, the main air spring chambers 11c and 11d are connected via a communication solenoid valve 22c, a communication pipe C, and a communication solenoid valve 22d.
The communication solenoid valve 22c also controls communication and isolation between the main air spring chamber 11c and the auxiliary air spring chamber 12c. Similarly, the communication solenoid valve 22d is connected to the main air spring chamber 11d.
It also controls communication and isolation between the air spring chamber 12d and the auxiliary air spring chamber 12d.

Note that the air supply solenoid valves 18a to 1
8d and the above exhaust solenoid valves 19a to 1
9d is a valve that is always closed, and the communication solenoid valves 22a to 22d are valves that are always open.

Next, the configuration of the air supply solenoid valves 18a to 18d will be explained using FIG. In FIG. 2, 31 is a valve body. This valve body 31 includes a valve passage 32 and a valve hole 3 which will be described later.
A valve passage 33 having a smaller diameter than 7 is formed. One end of the valve passage 32 is connected to the main air spring chambers 11a to 11d, and the other end is connected to the reserve tank 17. The valve passage 32 including the valve hole 37 is a passage for supplying a large amount of compressed air per unit time for attitude control. This valve passage 32 is controlled to open and close by a valve seat 35 attached to a plunger 34. That is, normally, the valve seat 35 is seated in the valve hole 37 by the biasing force of the return spring 36, and the valve hole 37 is closed. However, when the solenoid coil 38 is energized, the plunger 34 is attracted to the left and the valve seat 35
is removed from the valve hole 37, and the valve hole 37 is no longer blocked. Further, the valve passage 33 is a passage for supplying a smaller amount of compressed air per unit time than the valve passage 32 for vehicle height adjustment. This valve passage 33 is controlled to open and close by a valve seat 40 attached to a plunger 39. That is, normally, the valve seat 40 is seated in the valve hole 42 by the biasing force of the return spring 41, and the valve hole 42 is closed. However, when the solenoid coil 43 is energized, the plunger 39 is attracted to the right, the valve seat 40 is removed from the valve hole 42, and the valve hole 42 is no longer blocked.

In other words, during posture control, the solenoid coil 38
is excited, the valve hole 37 opens, and the reserve tank 1
7 to the main air spring chamber 11 via the valve passage 32
A large amount of compressed air is supplied to a to 11d. On the other hand, when adjusting the vehicle height, the solenoid coil 43 is energized, the valve hole 42 is opened, and the main air spring chambers 11a to 1 are supplied from the reserve tank 17 via the valve passage 33.
A small amount of compressed air is supplied to 1d.

Next, the configuration of the exhaust flow rate control solenoid valve 20 will be explained using FIG. In FIG. 3, 51 is a valve body. A valve passage 52 is formed in this valve body 51 . One end of the valve passage 52 is connected to the main air spring chamber 1.
1a to 11d, the other end is connected to the exhaust pipe 21. A partition wall 51 is integrally formed with the valve body 51 in the valve passage 52, and a small hole 54 is bored in the partition wall 51. Further, the opening and closing of the valve passage 52 is controlled by a valve seat 56 attached to a plunger 55. In other words,
Normally, the valve seat 56 is separated from the valve hole 58, which has a larger diameter than the small hole 54, due to the tension of the spring 57, and the valve hole 58 is unoccluded. However, when the solenoid coil 59 is energized, the plunger 55 is pushed downward, the valve seat 56 is seated in the valve hole 58, and the valve hole 58 is closed.

In other words, during posture control, solenoid coil 3
8 is released, the valve hole 58 opens and a large amount of compressed air per unit time flows from the main air spring chambers 11a to 11d through the valve hole 58 and the small hole 54 to the exhaust pipe 21.
is discharged to. On the other hand, when adjusting the vehicle height, the solenoid coil 59 is energized, the valve hole 58 is closed, and a small amount of compressed air per unit time is discharged from the main air spring chambers 11a to 11d to the exhaust pipe 21 through the small hole 54.

Next, the operation of the present invention configured as described above will be explained. For example, a case will be explained in which the vehicle height is lowered on the left side of the front and rear wheels of the vehicle, which occurs when the vehicle makes a right turn, thereby preventing the vehicle from rolling.

First, the communication solenoid valve 22b is closed to shut off the main air spring chamber 11b and the auxiliary air spring chamber 12b, and the air spring constant of the left front wheel suspension unit S _FL is made hard. As a result, communication between the main air spring chamber 11a and the main air spring chamber 11b is also cut off. Furthermore, the communication solenoid valve 22d
Close the main air spring chamber 11d and the sub air spring chamber 12.
d and the left rear wheel suspension unit.
Make the air spring constant of S _RL hard. This results in
Communication between the main air spring chamber 11c and the main air spring chamber 11d is also cut off.

Next, the solenoid coil 38 is energized and the air supply solenoid valves 22b and 22d are opened for a predetermined period of time to supply a large amount of compressed air per unit time from the reserve tank 17 to the main air spring chambers 11b and 11d. Raise the height.

Next, the communication solenoid valve 22a is closed to shut off the main air spring chamber 11a and the auxiliary air spring chamber 12a, and the air spring constant of the right front wheel suspension unit _SFR is made hard. As a result, communication between the main air spring chamber 11a and the main air spring chamber 11b is also cut off. Furthermore, the communication solenoid valve 22c
Close the main air spring chamber 11c and the sub air spring chamber 12.
C is shut off and the right rear wheel suspension unit
The air spring constant of S _RR is made hard. Thereby, communication between the main air spring chamber 11c and the main air spring chamber 11d is also cut off. Next, the exhaust solenoid valves 19a and 19c are opened for a predetermined period of time to exhaust the compressed air in the main air spring chambers 11a and 11c through the exhaust pipe 21, thereby lowering the vehicle height on the right side of the front and rear wheels. At this time, the exhaust flow rate control solenoid valve 2
0 solenoid coil 59 is in a de-energized state,
The flow rate of compressed air discharged from the main air spring chambers 11a and 11c is large per unit time. In this way, it is possible to sufficiently prevent the vehicle from rolling, which occurs when the vehicle makes a right turn, and to keep the vehicle body level. Hereinafter, after turning right, the communication solenoid valves 22a to 22d are opened to soften the air spring constants of each suspension unit S _FR , S _FL , S _RR , and S _RL , and to soften the air spring constants of the main air spring chambers of the front wheels. 1
The communication between 1a and 11b and between the rear wheel main air spring chambers 11c and 11d is returned to the communication state.

Also, when adjusting the vehicle height, solenoid valve 4
3 is excited and the air supply solenoid valve 18a~
18d is controlled to open and a small amount of compressed air in the reserve tank 17 is sent into the main air spring chambers 11a to 11d per unit time, and when adjusting the vehicle height, the exhaust solenoid valves 19a to 19d are controlled to open and the exhaust flow rate is controlled. The solenoid coil 59 of the solenoid valve 20 is energized and the main air spring chamber 1
This is done by discharging a small amount of the compressed air in the air in the air 1a to 11d per unit time via the exhaust solenoid valves 19a to 19d and the exhaust flow rate control solenoid valve 20. That is, when adjusting the vehicle height, a small amount of compressed air is supplied per unit time from the reserve tank 17 to the main air spring chambers 11a to 11d via the small diameter valve passage 33, and when adjusting the vehicle height, , the main air spring chambers 11a to 11d through small diameter holes 54.
Since a small amount of compressed air is discharged per unit time from the main air spring chambers 11a to 11d during vehicle height adjustment, the flow rate per unit time of compressed air supplied to and discharged from the main air spring chambers 11a to 11d is smaller than during attitude control. Therefore, it is possible to prevent the vehicle height from overshooting when adjusting the vehicle height.
Furthermore, since both the vehicle height adjustment and the vehicle height lowering adjustment are performed slowly, it is possible to eliminate the discomfort felt by the occupants when adjusting the vehicle height.

As described in detail above, according to the present invention, in a vehicle suspension device that controls the vehicle body posture and adjusts the vehicle height by supplying and discharging fluid in the fluid spring chamber of each suspension unit, the It is possible to provide a vehicle suspension device that can prevent high overshoot and passenger discomfort.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a vehicle suspension device according to an embodiment of the present invention, FIG. 2 is a sectional view of an air supply solenoid valve, and FIG. 3 is a sectional view of an exhaust flow rate control solenoid valve. 11a-11d...main air spring chamber, 12a-1
2d... Sub-air spring chamber, 17... Reserve tank, 18a-18d... Air supply solenoid valve, 19a-19d... Exhaust solenoid valve, 20... Exhaust flow rate control solenoid valve.

Claims (1)

[Claims] 1 A suspension unit provided for each wheel and having a fluid spring chamber, a fluid supply device that supplies fluid to each of the fluid spring chambers via a supply control valve, and a fluid supply device that supplies fluid to each of the fluid spring chambers through a supply control valve, and a and a fluid discharge device that discharges fluid through a control valve, and is configured to control the vehicle body posture by supplying fluid to a fluid spring on the outside of the turn and discharging fluid from the fluid spring on the inside of the turn during turning. In the suspension device, the fluid supply device and the fluid discharge device each have a vehicle height adjustment passage whose flow rate per unit time is smaller than a passage through which fluid passes when controlling the vehicle body posture, A vehicle suspension device that supplies and discharges fluid in the fluid spring through the vehicle height adjustment passage when adjusting the vehicle height.