JPS6283210A - Electronic control suspension device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electronic 111tll suspension device that improves running stability during high-speed running.

[Technical background of the invention and its problems] By interposing a fluid spring, such as an air spring chamber, between the wheel and the vehicle body, and controlling the supply and discharge of compressed air to this fluid spring chamber, Suspension If designed to suppress vehicle body roll! f is happy thinking about it. For example, when turning, the resuspension unit on the opposite side to the turning direction contracts, and the suspension unit on the turning direction tries to extend. A set amount of compressed air is discharged from the fluid spring chamber of the extensile suspension unit to reverse the tilt of the vehicle and keep the vehicle horizontal. In this way, the vehicle body is returned in the opposite direction to the roll direction by supplying and discharging fluid to and from the fluid spring chamber. In such an electronically controlled suspension system, it is desired to improve running stability when roll control is performed at high speeds.

[Objective of the Invention 1] The present invention has been made in view of the above points, and its object is to provide an electronically controlled suspension device that can improve running stability during high-speed running.

[Summary of the Invention] A suspension unit having a fluid spring chamber provided for each wheel, a fluid supply means for supplying fluid to each of the fluid spring chambers, and a fluid discharge means for discharging fluid from each of the fluid spring chambers. , a communication control means for controlling communication and non-communication between the left fluid spring chamber and the right fluid spring T; and a communication control means for controlling communication between the left and right fluid spring chambers and the left and right fluid springs when it is detected that a cause of rolling occurs in the vehicle body. a roll control means for disabling communication between the springs, supplying a setting fluid to the fluid spring chamber on the contraction side in the roll direction, and emitting a secondary surface signal to discharge the setting fluid from the fluid spring chamber on the extension side; In the suspension device, the vehicle speed detecting means detects the vehicle speed, and when the vehicle speed detecting means detects that the width speed exceeds a set value, the communication control means unconditionally disconnects the left and right fluid springs. In this way, the spring reaction force of the suspension is increased to improve high-speed running stability.

[Embodiment 1 of the Invention] Hereinafter, an electronically controlled suspension device according to an embodiment of the present invention will be described with reference to the drawings.

In Figure 1, FSL to air suspension unit 1
, FS2. Since R81 and R82 each have substantially the same structure, the air suspension unit will be described below using the symbol S, unless the front and rear suspension units are specifically explained.

That is, it incorporates an air suspension unit 3 + and a T-strut type shock absorber 1.
This shock absorber 1 includes a cylinder 2 attached to the front or rear wheel side, and a piston 3 fitted in the cylinder 2 so as to be freely movable. By moving up and down, it can effectively absorb shock.

By the way, 5 is a damping force switching valve, and the rotation of this damping force switching valve 5 is controlled by an actuator 5a, and the first damping chamber 6a and the second damping chamber 1eb are connected to the orifice a1.
The choice is made whether to communicate only through the orifices a1 and a2 (hard state) or through both orifices a1 and a2 (soft state). Note that the actuator 5a
The drive is controlled by a control unit 37, which will be described later.

Incidentally, a main air spring chamber 7 that also serves as a vehicle height adjustment fluid chamber is disposed coaxially with the piston rod 2 in the upper part of the shock absorber 1, and a bellows is installed in a part of the main air spring chamber 7. 8, the piston rod 4 can be raised by supplying and discharging air to the main air spring 7 through the passage 4a provided in the piston rod 4.

Further, a spring receiver 9a facing upward is provided on the outer wall of the shock absorber 1, and a spring receiver 9h facing downward is formed on the outer wall of the main air spring v7.
A coil spring 10 is loaded between these spring receivers 9a and Qb.

Thus, 11 is a compressor. The compressor 11 compresses the atmospheric air sent from the air cleaner 12 and supplies it to the dryer 13. The compressed air dried by silica gel etc. It is stored in the side reserve tank 15a. This reserve tank 15 is provided with a low pressure side reserve tank 15b. A compressor 1 driven by a compressor relay 17 is installed between the reserve tanks 15a and 15b.
6 is provided.

Further, a pressure switch 1B is provided which is turned on when the pressure in the low pressure side reserve tank 15b becomes higher than atmospheric pressure. When the pressure switch 18 is turned on, the compressor relay 17 is driven. This results in
The reserve tank 15b+ is kept at a pressure below atmospheric pressure. The route through which compressed air is supplied from the high-pressure side one reserve tank 15a to the suspension unit S is indicated by a solid arrow. That is, the compressed air from the reserve tank 15a is supplied to the air supply flow rate control valve 19, which is a three-way valve to be described later. Front wheel air supply solenoid valve 2
0. Check valve 21. Front Ishikawa solenoid valve 22°Front suspension unit FS2. It is sent to the front left suspension unit FSI.

Similarly, the compressed air from the reserve tank 15a is supplied to an air supply flow rate control valve 19, which is a three-way valve to be described later.
Air supply solenoid pulp 24° check valve 25 for ring invasion
．． Rear Ishikawa suspension unit R82, rear left suspension unit R8I via rear Ishikawa solenoid valve 26, rear left circle solenoid valve 27
sent to. Note that the downstream side of the check valve 21 and the downstream side of the check valve 25 are connected via a check valve 211. On the other hand, the exhaust route from the suspension unit S is indicated by a broken line arrow. In other words, suspension unit FS1. Exhaust from the FS2 is sent to the low pressure side reserve tank 15b via the solenoid valves 22, 23, the front exhaust valve 28, and the residual pressure valve 29. Furthermore, suspension unit FS1. Exhaust from FS2 is carried out through solenoid valves 22, 23, front exhaust valve 28, dryer 13. Exhaust solenoid valve 30
．． The air cleaner 12 is now opened to the atmosphere. Also,
Exhaust gas from the suspension units R81 and R82 is sent to the low pressure side reserve tank 15b via the solenoid valves 26 and 27, the rear exhaust valve 31, and the residual pressure valve 32. Note that when the pressure in the reserve tank 15b is lower than the pressure in the main air spring chamber 3, the residual pressure valves 29 and 32 are opened, and when the pressure in the reserve tank 15b is higher than the pressure in the main air spring chamber 3, the residual pressure valves 29 and 32 are opened. , 32 are in a closed state. Furthermore, suspension unit R8I.

Exhaust from R82 is carried out through solenoid valves 26, 27, rear exhaust valve 31, dryer 13. Exhaust solenoid valve 30. It is released to the atmosphere via the air cleaner 12. Reference numeral 33 denotes a pressure switch provided in a communication path communicating with the rear main air spring chamber 3, and its operation signal is output to a control unit to be described later.

Further, 34 is a vehicle height sensor, and this vehicle height sensor 34 is a vehicle height sensor.
The front vehicle height sensor 34F is attached to the lower arm 35 of the front right suspension of the II vehicle and detects the front vehicle height of the vehicle width, and the front vehicle height sensor 34F is attached to the lateral rod 36 of the rear left suspension of the vehicle JII vehicle. The vehicle includes a rear vehicle height sensor 34R that detects the vehicle height, and detection signals are supplied from these vehicle height sensors 3, 1F, and 34R to the control unit 37.

In each sensor 34F, 34F in the vehicle height sensor 34,
Distances from the normal mid-high level and low vehicle height level or high vehicle island level are detected respectively.

Furthermore, a vehicle speed sensor 38 is included in the speedometer, and this sensor 38 detects the vehicle speed and supplies the detected signal to the control unit 37.

In addition, for example, a left and right differential transformer type G sensor 39 is used as a vehicle body attitude sensor that detects changes in the attitude of a heavy object.
An acceleration sensor is provided to detect acceleration in the longitudinal direction. The output voltage V of this G sensor 39 increases as the acceleration G increases, and an example of the output voltage is shown in FIG. 4. Further, the time differential value of the voltage V becomes a value proportional to the steering wheel angular velocity or the brake depression speed.

Reference numeral 40 is an indicator for displaying oil pressure, and the display of this indicator 40 is controlled by the roll unit 1-37. Further, 41 is a steering sensor that detects the rotation angle of the steering wheel 42, that is, the steering angle, and its detection signal is sent to the control unit 37.

Further, numeral 44 is an accelerator opening sensor (not shown) that detects the depression angle of an accelerator pedal of the engine, and its detection signal is sent to the control unit 37. Also,
45 is a compressor relay for driving the compressor 11, and this compressor relay 45 is controlled by sub-section signals from the control unit 37 hl and others. Furthermore, there is a pressure switch that turns on when the pressure in the 4G [ma1 nosave tank 15a becomes below a predetermined value], and its output signal is the above-mentioned con! - Output to roll units 1-37. In other words, when the pressure in the reserve tank 15a falls below a predetermined value, the pressure switch 46 is turned on, and the compressor relay 45 is activated under the control of the control unit 31.

As a result, the compressor 11 is driven and compressed air is sent into the reserve tank 15a.
The internal pressure of 5a is made equal to or higher than a predetermined value. J3, the above solenoid valve 20.22.23.24.26.27°30
The opening/closing control of the valves 19, 28, and 31 is performed by the υl1fl signal from the control unit 37.

In addition, the solenoid valves 22, 23, 26, 27 and valves 19, 28, 31 are three-way valves, and the second
The two states are shown in Figure 2. FIG. 2 (A>) shows a state in which the three-way valve is driven, and in this state compressed air moves along the path indicated by the arrow.

On the other hand, FIG. 2(B) shows a state in which the three-way valve is not driven, and in this state compressed air moves along the path indicated by arrow B. Also, solenoid valve 20.24.3
0 consists of a two-way valve, and for its two states the fourth
It is shown in the figure. Figure 3 (A>) shows the state in which the solenoid valve is driven, and in this state compressed air moves in the direction of arrow C. On the other hand, when the solenoid valve is not driven, it is shown in Figure 3 (8). In this case, there is no flow of compressed air.

Next, the operation of an embodiment of the present invention configured as described above will be explained. First, an overview of each control mode will be explained with reference to the valve opening/closing diagram shown in FIG. First, roll control when turning the vehicle to the right by steering the steering wheel to the right will be explained.

In this case, the vehicle height of the suspension unit on the left side of the vehicle body tends to decrease, and the vehicle height of the suspension unit on the right side of the vehicle body tends to increase. For this reason, the front wheel air intake solenoid valve 20, the rear wheel air intake solenoid valve 24,
The front right solenoid valve 22 and the rear right solenoid valve 26 operate the control unit 3 for a set time.
It is opened by a control signal from 7. As a result, the compressed air stored in the reserve tank 15a is sent to the main air spring chamber 7 of the front left suspension unit via the front wheel solenoid valve 20 and the front left solenoid valve 23. Further, the compressed air stored in the reserve tank 15a is sent to the main air spring chamber 7 of the rear left suspension unit via the rear wheel air supply solenoid valve 24 and the rear left solenoid valve 27.

This biases the left suspension unit in a direction that increases the vehicle height. On the other hand, compressed air discharged from the main air spring chamber 7h1 of the suspension unit on the right side of the front 1 is discharged in a set amount to the reserve tank 15b via the front right solenoid valve 22 and the front exhaust valve 28. Similarly, compressed air discharged from the main air spring v7 of the rear right suspension unit is discharged in a set amount to the reserve tank 15b via the rear right solenoid valve 26 and the rear exhaust valve 31.

This biases the right suspension unit in a direction that lowers the vehicle height. In this way, when turning right, the vehicle height of the left suspension unit is lowered, and the vehicle height of the right suspension unit is prevented from increasing. The above processing is the start mode, and when the start mode processing is finished, the process moves to the holding mode. That is, the @width air intake solenoid valve 20 and the rear wheel air intake solenoid valve 24 are closed. As a result, the air supply to the main air springs 7 of the front left suspension unit and the rear left suspension unit is stopped.

Furthermore, a front exhaust valve 28 and a rear exhaust valve 3
1 is driven and compressed air is discharged from the main air spring chamber 7 of the front right suspension unit and the rear right suspension unit. This maintains the roll controlled state. Then, when the right turn is completed, all valves are turned off.

As a result, the main air spring chambers 7 of the left and right suspension units are communicated via the front Ishikawa solenoid valve 22 and the front left circular solenoid valve 23, the rear Ishikawa solenoid valve 26, and the V left solenoid valve 27. Therefore, the main air springs 7 of the left and right suspension units are maintained at the same pressure. This releases Role IIIi. .

Next, the roll control (2) when turning the vehicle to the left by steering the steering wheel to the left will be explained. In this case, the vehicle height of the suspension unit on the side of the intermediate body in the IJ tends to decrease, and the vehicle height of the suspension unit on the left side of the intermediate body tends to increase.

Therefore, the front wheel air intake solenoid valve 20, the rear wheel air intake solenoid valve 24, the front left solenoid valve 23, and the rear left solenoid valve 27 are opened by the control signal from the control unit 37 for a set time. As a result, [
Compressed air is supplied by the front wheel air supply solenoid valve 20, front t.
It is sent to the main air spring chamber 7 of the front right suspension unit via the right solenoid valve 22.

Further, the compressed air stored in the reserve tank 15a is sent to the main air spring 7 of the rear left suspension unit via the rear width air supply solenoid valve 24 and the rear right solenoid valve 26. As a result, the right suspension unit is biased in a direction that increases the vehicle height. On the other hand, the compressed air discharged from the main air spring 7 of the front left suspension unit is discharged in a set amount to the reserve tank 15b via the front left solenoid valve 23 and the freon 1 to exhaust valve 28. In addition, the main air spring chamber 7 of the rear left suspension unit is also similar to the
The compressed air discharged from the rear left solenoid valve 2
1. Reserve tank 15b via rear exhaust valve 31
Only the set amount is discharged. As a result, the left suspension unit 1- is biased in a direction that lowers the vehicle height. In this way, when the vehicle turns left, the vehicle height of the right suspension unit is lowered, and the vehicle height of the left suspension unit is prevented from increasing. The above process is the start mode, and the process in the start mode is transferred to the process in the hold mode. That is, the front wheel air intake solenoid valve 20 and the rear wheel air intake solenoid valve 24 are closed. As a result, the air supply to the main air spring chamber 7 of the front right suspension unit and the rear right suspension unit is stopped. Further, the front exhaust valve 28 and the rear exhaust valve 31 are driven to stop the discharge of compressed air from the main air spring joints 7 of the front left and rear left suspension units. This maintains the roll controlled state. At the end of the left turn, all valves are turned off. As a result, the main air spring chambers 7 of the left and right suspension units are communicated via the front Ishikawa solenoid valve 22 and the front left solenoid valve 23, and through the rear left solenoid valve 26 and rear left solenoid valve 27. Therefore, the main air springs 7 of the left and right suspension units are maintained at the same pressure. This releases roll control.

Next, nose dive control will be explained. This 11
1111 is designed to prevent the front part of the automatic vehicle from going down and the rear part of the car from going up when the brake is stepped on. First, the front wheel air intake solenoid valve 20 is used as the starting mode in which this nose dial starts.
．． Rear Ishikawa and rear left solenoid valve 26.27
is turned on. As a result, the reserve tank 15 is placed in the main air spring chamber 7 of the front left and right suspension units.
Compressed air is supplied from a. Then, compressed air flows from the main air springs 7 of the rear left and right suspension units to the solenoid valves 26 and 27 and the rear exhaust valve 31.

It is discharged to the reserve tank 15b through the tank. The valves that were turned on for a long time are then turned off. As a result, air supply to the front suspension unit is stopped, and exhaust air from the rear suspension unit is also stopped. Due to this.

Move to hold mode. By the way, when the brake is no longer depressed, the control shown in the above-mentioned start mode is no longer necessary. Therefore, as return control, the rear wheel intake solenoid valve 24, the front right and left solenoid valves 22.2
3 are each turned on. As a result, the compressed air discharged from the main air spring chambers 7 of the front right and left suspension units is sent to the reserve tank 15b via the solenoid valves 22, 23 and the front exhaust valve 28. Further, the compressed air from the reserve tank 15a is supplied to the rear wheel air supply solenoid valve 24, the solenoid valve 26.
27 to the main air spring π7 of the rear wheel suspension unit. This returns the vehicle to the state before nose dive control.

Next, Sukhwat 11 suburb will be explained. The control system prevents the front of the car from rising and the rear of the car from falling when the accelerator is suddenly pressed. First, the rear wheel air intake solenoid valve 24 is turned on as a start mode in which the swift I+ 11 is started. As a result, the reserve tank 15 is connected to the main air spring seedlings 7 of the rear left and right suspension units.
Compressed air is supplied from a. As a result, the vehicle height on the rear side is raised. Then, after a predetermined period of time, the above-mentioned turned-on valve is turned off. This stops the air supply to the rear suspension unit. This moves to holding mode. By the way, when the accelerator is no longer depressed, the control shown in the above-mentioned start mode is no longer necessary. Therefore, as a return control, the front wheel air intake solenoid valve 20 and the rear and left solenoid valves 2G and 27 are turned on, respectively.

This allows the main air springs of the rear right and left suspension units! The compressed air discharged from the tank 7 is sent to the reserve tank 15b via the solenoid valves 26, 27 and the rear exhaust valve 31. In addition, the reserve tank 15a
The compressed air is supplied to the main air spring chamber 7 of the front wheel suspension unit 1- through the front wheel air supply solenoid valve 20 and the solenoid valves 22 and 23. This returns the state to the state before performing the squat λ control.

Next, a case will be described in which the vehicle height is adjusted slowly. First, the case of raising the vehicle height will be explained. In this case, the front wheel air intake solenoid valve 20 and the rear wheel air intake solenoid valve 24 are turned on, and the air intake flow layer control valve 19 is turned on. For this reason, reserve tank 15a
The compressed air sent from the dia.
, to the suspension unit main air springs 7 on the front and rear wheels through solenoid valves 22, 23, 26, 27.

This raises the vehicle height.

On the other hand, the case of lowering the vehicle height will be explained. In this case, front and rear exhaust valves 28.31, exhaust solenoid valve 30. Solenoid valve 22゜23, 26.
27 turns on. As a result, the compressed air discharged from the main air spring chambers 7 of the front and rear suspension units is transferred to the solenoid valves 22, 23, 26, 27, the front exhaust valve 28. [air valve 31, dryer 13, exhaust solenoid valve 30, air cleaner 12]
is emitted to the atmosphere via In this case dry 1713
is played.

Next, a case in which the vehicle height is rapidly raised will be explained. In this case, the front wheel air intake solenoid valve 20 and the rear wheel air intake solenoid valve 24 are opened.

As a result, the compressed air from the reserve tank 15a is supplied to the main air spring 7 of the front and rear suspension units via the large diameter tube of the valve 19 and the solenoid valves 22, 23, 26, 27. Ru.

In this case, the supplied compressed air is supplied through the large-diameter pipe of the air supply flow rate control valve 19, so the supply area of compressed air can be increased, and the vehicle height can be adjusted rapidly. I can do it.

Next, a case will be described in which the main air springs 7 of the left and right suspension units are made non-communicating to maintain a roll-controlled state. In this case, the front exhaust valve 28
This is done by turning on the rear exhaust pulse 131 and turning on the front Ishikawa solenoid valve 22 and the rear 6 solenoid valve 26. As a result, the main air spring chambers 7 of the left and right suspension units
The space between them is considered to be non-communicating.

As described above, attitude control is performed by the suspension device having the configuration shown in FIG.

Next, the operation of an embodiment of the present invention configured as described above will be explained. 6(A) and 6(B) show the operations performed by the control unit 37. FIG. First, as an initial setting, the left and right main air springs 7 to the suspension unit 1 are communicated.

In addition, the memory area lower m that stores the control time for controlling the solenoid valve is reset (step S
1). Next, the vehicle speed V detected by the vehicle speed sensor 38, the steering angle θh of the steering wheel detected by the steering sensor 41, and the steering wheel angular velocity aeh detected based on the steering angle θh are read into the control unit 37 (step S2 >.

Subsequently, it is determined whether the vehicle speed V is greater than 201'J/h (step $3). Here, car IVtfi
If it is larger than 20 Km'h, it is determined as rYEsJ and the process proceeds to step S4. Then, the vehicle speed V is t20 K
It is determined whether ta is greater than 7r+. Here, if the vehicle speed V is greater than 120 km/h, step S
Proceeding to step 5, the main air springs v7 of the left and right suspension units are disconnected from each other. This increases the spring reaction force of the suspension unit, improving stability during high-speed driving.

On the other hand, in step S4 above, rNC)! In other words, if it is determined that the vehicle speed (■) is less than 1201 m/h, the process proceeds to step S6, where it is determined whether the steering angle eh of the steering wheel is greater than 100 and less than θO.

In other words, it is determined whether the steering wheel is in the neutral range.

rN] in this step S6, the process advances to step S7. In this step S7, it is determined whether the above-mentioned handle angular velocity 6h is equal to or higher than a predetermined angular velocity 00. Then, if "θ≧θO", the control time Tp for opening the valve is determined from the V-θ map shown in FIG. 7 (step 88). On the other hand, “θ〈θO
If J, tll'mvfHTo for opening the valve is determined from the ve map shown in FIG. 8 (step 89). Then, TmTp-Tm is calculated (step 510). Here, since the aM step is set to Tm-0, when the step 310 is first proceeded to, the WJ time is based on the T-Tpffi system. Next, the process proceeds to step 811, where it is determined whether "T>0". Here, if rT>OJr, roll control is started (step 512). Here, this roll control is either right turn control or left turn back control of the attitude control explained using FIG. 5. Then, when the roll control ends, Tm is set to lower. and,
It is determined whether the steering wheel is on the return side (step 514). Here, if it is determined that the steering wheel has been steered to the return side, the process returns to step $1, and the seed air springs 7 of the left and right suspension units are communicated with each other. This returns the state to the state before roll control.

On the other hand, if it is determined in step 314 that the handle is not on the return side, the suspension air springs 7 of the left and right suspension units are disconnected from each other. If the communication is already disconnected, that state is maintained. Then, the process returns to step S2 and the various monitors are read into the control unit 37 again. Below are steps $
If the processes from 3 onwards are repeated and the control j11 time To obtained in step S8 or S9 increases, T=Tρ-Tm>Q in the process of step S10, so additional roll control is performed in step 812. be exposed.

By the way, when the steering wheel is returned to the neutral range, rYEsj is determined in step S6, and the process returns to step S1, where the main air springs 7 of the left and right suspension units are communicated with each other, and the roll control is completed.

[Effects of the Invention] As detailed above, according to the present invention, it is possible to provide an electronically controlled suspension device that can improve running stability during high-speed running.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an electronically controlled suspension device according to an embodiment of the present invention, FIG. and (B)
Figure 4 shows the activated and non-activated states of the solenoid valve.
The figure shows an example of the output voltage of the G sensor, Figure 5 shows the opening and closing of the valves for attitude control and vehicle height adjustment, and Figure 6 (A)
and (B) are flowcharts (to,
FIG. 7 is a diagram showing a vehicle speed-steering wheel angular velocity map, and FIG. 8 is a diagram showing a vehicle speed-steering wheel angle map. 11... Compressor, 15... Reserve tank,
19...Air supply flow rate control Co., Ltd. valve, 20...Air supply solenoid valve for front wheels, 24...Air supply solenoid valve for rear wheels, 28...Front exhaust valve, 31...
rear exhaust valve. Applicant's agent Patent attorney Takeshi Suzue Foolish plan 2
Figure 3 (A) (A) Figure 4 Figure 6 (A) Figure 6 CB) Figure 7 Figure 8

Claims (1)

[Claims] A suspension unit provided for each wheel and having a fluid spring chamber, a fluid supply means for supplying fluid to each of the fluid spring chambers, a fluid discharge means for discharging fluid from each fluid spring chamber, and a left fluid A communication control means for controlling communication and non-communication between the spring chamber and the right fluid spring chamber, and a communication control means for controlling communication between the left and right fluid spring chambers when it is detected that a cause of rolling occurs in the vehicle body. and a roll control means for supplying a set amount of fluid to the fluid spring chamber on the contraction side in the roll direction and issuing a control signal to discharge the set amount of fluid from the fluid spring chamber on the extension side, The vehicle is equipped with a vehicle speed detection means for detecting vehicle speed, and a control means for unconditionally disconnecting the left and right fluid spring chambers by the communication control means when the vehicle speed detection means detects a vehicle speed equal to or higher than a set value. An electronically controlled suspension device characterized by: