JPH0592713A - Vehicle suspension - Google Patents

Abstract

PURPOSE:To secure stable traveling condition even in the case where abnormalities are detected by fixing the detected value of the traveling condition to the value immediately before the abnormalities are detected, if any abnormalities of a traveling condition detecting means are detected in a case when an actuator to suppress swaying of a vehicle is controlled on the basis of the traveling condition of the vehicle. CONSTITUTION:Swaying of the rolling motion, the pitching motion and the bounce motion of a vehicle is suppressed by means of an actuator (A) in a suspension for the vehicle. The traveling condition of the vehicle is detected by a traveling condition detecting means (B). In addition, the actuator (A) is controlled by a controlling means (C) on the basis of the detected traveling condition. In the above constitution, the abnormalities of the traveling condition detecting means (B) are detected by an abnormality detecting means (D). When the abnormalities are detected, the detected value of the traveling condition is fixed to the detected value of the traveling condition immediately before the abnormalities are detected. This arrangement allows suppression of the changes in the posture or the steering characteristics of the vehicle in an abnormal condition of the traveling condition detecting means (B) and securing a stable traveling condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle suspension capable of suppressing a roll, pitch or bounce of a vehicle.

[0002]

2. Description of the Related Art As a conventional vehicle suspension,
There is one described in Japanese Patent Application Laid-Open No. 63-188511 previously proposed by the present applicant. In this conventional example, a sensor abnormality detecting unit that detects a predetermined abnormal state of a vehicle behavior sensor based on behavior information output from the sensor, and when the vehicle abnormality sensor detects that the vehicle behavior sensor is in an abnormal state In addition, a behavior information value fixing means for fixing the value of the behavior information to a predetermined value is provided.

[0003]

However, in the above-described conventional vehicle suspension, when the vehicle behavior sensor is detected to be in an abnormal state, the behavior information value is set to a predetermined value (particularly forcing the actuator to operate). Since the fail-safe function is exhibited by fixing the value to a value that causes the anti-roll moment to be generated, the actuator is actuated according to the lateral acceleration detection value of the lateral acceleration sensor during vehicle turning to generate an anti-roll moment. If the lateral acceleration sensor is broken in such a state that the lateral acceleration detection value is fixed to zero or the maximum value of either left or right, the anti-roll moment promotes zero or roll. There is an unsolved problem that the vehicle attitude or the vehicle steer characteristic is changed by changing the value.

Therefore, the present invention has been made by paying attention to the unsolved problem of the above conventional example, and suppresses the change of the vehicle attitude or the vehicle steer characteristic when an abnormal state occurs in the running state detecting means. It is an object of the present invention to provide a vehicle suspension that can be used.

[0005]

In order to achieve the above object, a vehicle suspension according to the present invention, as shown in the basic configuration diagram of FIG.
A vehicle including an actuator that suppresses swinging such as bounce motion, a traveling state detection unit that detects a traveling state of the vehicle, and a control unit that controls the actuator based on a traveling state detection value of the traveling state detection unit. In the vehicle suspension, the abnormality detecting means for detecting an abnormality of the traveling state detecting means, and when the abnormality is detected by the abnormality detecting means, the traveling state detected value of the traveling state detecting means is fixed to the immediately preceding traveling state detected value. And a detection value fixing means.

[0006]

In the present invention, when the abnormality detecting means detects an abnormal state of the running state detecting means such as the lateral acceleration sensor, the longitudinal acceleration sensor, the vertical acceleration sensor, the wheel speed sensor, the yaw rate sensor, the steering angle sensor, etc. By fixing the traveling state detection value of the traveling state detection means immediately before the abnormality occurs as the traveling state detection value by the value fixing means, the vehicle posture change and the vehicle steer characteristic change due to the change of the traveling state detection value of the traveling state detection means. Can be suppressed.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a schematic configuration diagram showing an embodiment when the present invention is applied to an active suspension.

In the figure, 11FL to 11RR are active suspensions interposed between a vehicle body side member 12 and a wheel side member 14 that individually supports the wheels 13FL to 13RR, respectively, and are fluid pressures. Hydraulic cylinders 15FL to 15RR as cylinders, coil springs 16FL to 16RR interposed in parallel with these hydraulic cylinders 15FL to 15RR, and hydraulic cylinders 15FL to 14
Pressure control valves 17FL to 17RR for controlling the operating hydraulic pressure for the RR in response to a command value from a control device 31 described later.
It has and.

Here, the hydraulic cylinders 15FL to 15RR
Each of those cylinder tubes 15a is attached to the wheel side member 14, the piston rod 15b is attached to the vehicle body side member 12, and the upper and lower pressure chambers defined by the piston 15c having the through hole in the cylinder tube 15a The thrust corresponding to the operating hydraulic pressure supplied from the pressure control valves 17FL to 17RR is generated by the difference in pressure receiving area with respect to the piston 15c. Also, coil spring 16F
Each of L to 16RR supports a static load of the vehicle body, and may have a low spring constant that only supports the static load.

Each of the pressure control valves 17FL to 17RR has an input port 17i, a return port 17o and a control pressure port 17c, and the control pressure port 17c and the input port 17i and the return port 17o are closed or controlled. The spool 17c has a spool for switching the communication state to communicate with either the input port 17i or the return port 17o, the supply pressure and the control pressure are supplied as pilot pressures to both ends of the spool, and the proportional solenoid is provided on the supply pressure side. It has a configuration in which a poppet valve controlled by 17s is arranged, and the pressure P _C of the control pressure port 17c always depends on the exciting currents I _{FL to} I _RR supplied to the proportional solenoid 17s from the controller 31 described later. It is controlled so that it becomes pressure.

Here, the exciting current I_FL~ I_RRAnd control pressure port
Control oil pressure P output from the motor 17c _CThe relationship with
As shown in FIG._FL~ I_RRWhen is near zero
To P _MINIs output, and the exciting current I is output from this state._FL~ I_RRBut
When it increases in the positive direction, a predetermined proportional gain K₁Have
Control hydraulic pressure P_CIncrease from the hydraulic power source 23, which will be described later.
Setting line pressure P_HIs saturated with.

The input port 17i and the return port 17o of the pressure control valves 17FL to 17RR are connected to the hydraulic pressure source 23 via the supply side pipe 21 and the return side pipe 22, respectively, and the control pressure port 17c is connected via the hydraulic pipe 24. Are connected to the pressure chambers of the hydraulic cylinders 15FL to 15RR. In FIG. 2, 25 is a high pressure side accumulator connected in the middle of the supply side pipe 24, and 26 is a pressure control valve 1.
The unsprung vibration absorbing accumulator is connected to the hydraulic pipe 24 between the 7FL to 17RR and the hydraulic cylinders 15FL to 15RR via the throttle 27.

On the other hand, the vehicle body has a lateral acceleration generated in the vehicle body.
Lateral acceleration sensor 28 for detecting the
The longitudinal acceleration sensor 29 for detecting the acceleration is in the right place.
It is provided. The lateral acceleration sensor 28 is shown in FIG.
As described above, when the lateral acceleration is zero, the neutral voltage V_NLateral acceleration
Degree detection value Y_G0Is output to the left of the vehicle by turning the vehicle to the right.
Lateral acceleration detected value Y when lateral acceleration in the direction occurs_G0Than
Low lateral acceleration detection value Y _GIs output and the vehicle turns left
Lateral acceleration is detected when lateral acceleration occurs to the right of the vehicle body
Value Y_G0Higher lateral acceleration detection value Y_GIs output. Also,
The longitudinal acceleration sensor 29 also accelerates longitudinally, as shown in FIG.
When the degree is zero, the neutral voltage V_NLongitudinal acceleration detection value X
_G0Is output, and the acceleration of the vehicle causes the vehicle to move backward
Longitudinal acceleration detection value X when speed occurs_G0Before and after lower
Acceleration detection value X_GIs output and the vehicle body decelerates
The longitudinal acceleration detection value X when a forward deceleration occurs
_G0Higher longitudinal acceleration detection value X_GIs output.

Further, the vehicle body side member 12 and the wheel side member 14
Vehicle height sensors 30FL to 30RR are provided between the vehicle height sensor 30 and the vehicle height sensors 30FL to 30RR.
FL to 30RR is composed of, for example, a potentiometer,
Vehicle height detection value H _FL which consists of analog voltage according to relative distance
Outputs H _RR . Then, the detection values of the lateral acceleration sensor 28, the longitudinal acceleration sensor 29, and the vehicle height sensors 30FL to 30RR are supplied to the control device 31.

As shown in FIG. 6, the control device 31 includes a microcomputer 32 and the microcomputer 3
The control valve drive circuits 33FL to 33RR to which the pressure command values P _{FL to} P _RR output from the control valve 2 are input. The microcomputer 32 has at least an interface circuit 32a, an arithmetic processing unit 32b, and a storage device 32c. The interface circuit 32a has a lateral acceleration detection device 28 and a lateral acceleration detection value Y _{G of the} longitudinal acceleration detection value 29 on its input side. And the longitudinal acceleration detection value X _G is the A / D converter 3
The vehicle height detection values H _{FL to} H _{RR of the} vehicle height sensors 30FL to 30RR are input via the 4Y and 34X, and are A / D.
The pressure command values P _{FL to} P _RR input from the converters 35FL to 35RR and output from the output side are converted into D / A converters 36.
The voltage is converted to an analog voltage by FL to 36RR and supplied to the control valve drive circuits 33FL to 33RR.

The arithmetic processing unit 32b reads the vehicle height detection values H _{FL to} H _RR of the vehicle height sensors 30FL to 30RR via the interface circuit 32a and compares these with the preset target vehicle height value H _S , The vehicle height command values PH _{FL to} PH _RR so that the vehicle height detection values H _{FL to} H _RR match the target vehicle height value H _S.
And the lateral acceleration detection value Y of the lateral acceleration sensor 28.
_G is read to determine whether or not the lateral acceleration detection value Y _G is normal, and when normal, the roll suppression command value PL is calculated based on the read lateral acceleration detection value Y _{G (n).} If it is abnormal, the lateral acceleration detection value Y read last time is read.
To calculate the roll-reduction command value PL based on _{G (n-1),} Nde read longitudinal acceleration detection value X _G of the longitudinal acceleration sensor 29, calculates a pitch control command value PP based on the longitudinal acceleration detection value X _G Then, the command values P _{FL to} P _RR for suppressing the posture change of the vehicle body are calculated by adding / subtracting each command value, and these are inputted to the D / A converter 34FL via the interface circuit 32a.
Output to ~ 34RR.

The storage device 32c is composed of a ROM, a RAM and the like, stores a program necessary for the arithmetic processing of the arithmetic processing device 32b in advance, and the arithmetic processing device 32.
The calculation result of b is sequentially stored. In addition, the control valve drive circuit 3
Each of 3FL to 33RR is composed of, for example, a floating type constant current circuit, and the pressure command voltage V _FL to be input is input.
Excitation currents I _{FL to} I _RR corresponding to V _RR are applied to each pressure control valve 17F.
It supplies to the proportional solenoid 17s of L-17RR.

Next, the operation of the above embodiment will be described with reference to the arithmetic processing unit 3.
2B will be described with reference to the flowchart of FIG. When the ignition switch is turned on,
The control device 31 is powered on, and the arithmetic processing device 32 is turned on.
At b, the posture change suppressing process shown in FIG. 7 is executed. That is, first, in step S1, each pressure control valve 17FL to 17R is
The pressure command values P _{FL to} P _RR for R are required to maintain the target vehicle height value H _S in the standard loading state.
Set to _S.

Next, in step S2, the vehicle height detection values H _{FL to} H _RR of the vehicle height sensors 30FL to 30RR are read, and the vehicle height detection values H _i (i = _{FL to RR)} are read in steps S3 to. The vehicle height adjustment pressure command value PH _i is calculated by performing the processing of S7. That is, in step S3, it is determined whether the vehicle height detection value H _i and the target vehicle height value H _S are equal. If H _i ≠ H _S , it is determined that vehicle height adjustment is necessary, and step S4 is performed. Then, it is determined whether or not the vehicle height detection value H _i exceeds the target vehicle height value H _S. At this time, when H _i > H _S, it is determined that the vehicle height needs to be lowered, the process proceeds to step S5, and the pressure command value PH _{i (j-1)} at the time of the previous processing is preset. A value obtained by subtracting the predetermined value ΔH is a new pressure command value PH _{i (j)} (= PH _{i (j-1)}
-ΔH), which is updated and stored in the vehicle height adjustment pressure command value storage area of the storage device 32c, and then step S7.
When H _i <H _S, it is determined that the vehicle height needs to be increased, and the process proceeds to step S6 to preset the pressure command value PH _{i (j-1)} at the time of the previous processing. The new pressure command value PH _{i (j)} (= PH
_{i (j-1)} + ΔH), which is updated and stored in the vehicle height adjustment pressure command value storage area of the storage device 32c, and then the vehicle height adjustment processing is ended and the process proceeds to step S7.

In step S7, the lateral acceleration sensor 2
Lateral acceleration detection value Y of 8_{G (n)}Read, then step S
8, the lateral acceleration detection value Y_{G (n)}To lateral acceleration
Acceleration detection value Y when is zero_GNBy subtracting
The lateral acceleration when turning left is positive, and the lateral acceleration when turning right is negative.
Actual lateral acceleration detection value Y corresponding to the actual lateral acceleration
_{GR (n)}Is calculated, and then the process proceeds to step S9 to calculate
Actual lateral acceleration detection value Y _{GR (n)}Predetermined in the storage device 32c
Update and store in the storage area, and then move to step S10
It

In step S10, an abnormal flag described later is
Rag F_AIs set, and the abnormal flag
Gu F_AWhen is not set, the lateral acceleration sensor
28 is determined to be normal, and the process proceeds to step S11.
It In this step S11, it is stored in step S9.
Actual lateral acceleration detection value Y _{GR (n)}To the previous actual lateral acceleration
Detection value Y_{GR (n-1)}Absolute value of the difference value obtained by subtracting | Y_{GR (n )}−
Y_{GR (n-1)}Whether | exceeds the preset allowable value ε
To determine. At this time, | Y_{GR (n)}-Y_{GR (n-1)}｜ ＞
When ε, the lateral acceleration sensor 28 is in an abnormal state.
If it is determined that the lateral acceleration
Abnormality flag F indicating that the sensor 28 is in an abnormal state_A
Is set to “1”, and then the process proceeds to step S13.
Calculated lateral acceleration value Y_GOPLater acceleration read as
Degree detection value Y_{G (n-1)}Actual lateral acceleration detection value Y based on_{GR (n-1)}
Is adopted and updated to a predetermined storage area of the storage device 32c.
After storing, the process proceeds to step S15. Also,
The judgment result of S11 is | Y_{GR (n)}-Y_{GR (n-1)}| ≦ ε
At some time, it is assumed that the lateral acceleration sensor 28 is normal.
Judgment is made and the process proceeds to step S14 to detect the lateral acceleration for calculation.
Value Y_GOPLateral acceleration detection value Y read this time as_{G (n)}Based on
Actual lateral acceleration detection value Y_{GR (n)}Adopt this and store this
Setting₃₂After updating and storing in a predetermined storage area of c, step S1
Go to 5.

In step S15, the actual lateral acceleration detection value Y
_GRA predetermined roll suppression control gain K _YMultiply and roll
The suppression pressure command value PL is calculated and stored in the storage device 32c.
After the roll suppression pressure command value storage area is updated and stored,
Then, the control process ends and the process proceeds to step S16. this
In step S16, the longitudinal acceleration of the longitudinal acceleration detector 29 is applied.
Speed detection value X_GIs read, and then the process proceeds to step S17.
Then the longitudinal acceleration detection value X_GTo longitudinal acceleration X_GIs zero
Acceleration detection value X_G0Forward by subtracting
The actual longitudinal acceleration with positive acceleration and negative deceleration
Corresponding actual longitudinal acceleration detection value X_GRAnd then
The actual front-back acceleration detection value X_GRGiven to
Pitch suppression control gain K_XMultiply the pitch suppression pressure finger
Calculate the command value PP and suppress the pitch of the memory device 32c.
Pitch suppression processing after updating and storing in the pressure command value storage area
Is completed and the process proceeds to step S19.

In step S19, the storage device 32c
Each of the pressure command values PH _{FL to} PH _RR , PL and PP stored in the vehicle height adjustment pressure command value storage region, the roll suppression pressure command value storage region and the pitch suppression pressure command value storage region are read out, and based on these, Then, the following equations (1) to (4) are calculated to calculate the pressure command values P _{FL to} P _RR for the pressure control valves 15FL to 15RR.

P _FL = PH _FL -PL + PP (1) P _FR = PH _FR + PL + PP (2) P _RL = PH _RL -PL-PP (3) P _RR = PH _RR + PL-PP (4) Then, the process proceeds to step S20 and the above step S1.
After outputting the pressure command values P _{FL to} P _RR calculated in step 9, the process proceeds to step S21 to determine whether a predetermined control end condition is satisfied. If the control end condition is not satisfied, the process returns to step S2. When the control termination condition is satisfied, the processing is terminated. Here, as the control end condition,
It is set when a predetermined time elapses after the ignition switch is switched from the on state to the off state, and the power-on state of the control device 31 is self-maintained for a predetermined time even after the ignition switch is turned off. ..

Therefore, the vehicle is now stopped on a flat road surface.
When the lateral acceleration sensor 28 is normal,
Positive neutral voltage V from the lateral acceleration sensor 28_NIs acceleration detection
Value Y _GIs output as. For this reason, the steps in FIG.
In step S8, the actual lateral acceleration detected value Y_{GR (n)}Is zero
And is stored in a predetermined storage area of the storage device 32c.
Previous actual lateral acceleration detection value Y_{GR (n-1)}Is also zero
Therefore, in step S11, | Y_{GR (n)}-Y_{GR (n-1)}
Since it is determined that | ≦ ε, the process proceeds to step S14,
Actual lateral acceleration detection value Y_{GR (n)}Lateral acceleration detection
Value Y_GOIs updated and stored as
Then, the roll suppression pressure command value PL is calculated. This and
Lateral acceleration detection value Y for calculation_GOIs zero, so the roll
The suppression pressure command value PL also becomes zero. On the other hand, the longitudinal acceleration sensor
Longitudinal acceleration detection value X output from the sensor 29_GAlso positive neutral
Voltage V_NTherefore, the actual calculated in step S17
Rear acceleration detection value X_{GR (n)}Also becomes zero pitch suppression pressure finger
The command value PP also becomes zero, and the occupants get on and off or the load is loaded and unloaded.
Pressure command value P that suppresses vehicle height change due to_FL~ P_RRIs arithmetic
Are output to the D / A converters 35FL to 35RR.
The D / A converters 35FL to 35FL
Command voltage V output from RR_FL~ V_RRExcitation corresponding to
Current I_FL~ I_RRIs the control valve drive circuit 33FL to 33RR
From the pressure control valve 17FL to 17RR proportional solenoid 17
of the pressure control valves 17FL to 17RR.
Control pressure P_CIncreases and decreases, and hydraulic cylinders 15FL to 15RR
The vehicle height matches the target vehicle height by changing the thrust of
To be done.

That is, when the vehicle height is lowered (or increased) by the passenger getting on (or getting off), in the process of FIG. 7, the process proceeds to step S4 via steps S2 and S3, and H _i <H _S (or Since H _i > H _S ), the process proceeds to step S6 (or step S5), and the predetermined value ΔH is added (or subtracted) to the previous vehicle height adjustment pressure command value PH _{i (j-1).} , The vehicle height adjustment pressure command value PH _{i (j)} increases (or decreases), and the pressure command values P _{FL to} P _FL are correspondingly increased.
_By increasing (or decreasing) _RR , hydraulic cylinder 1
The vehicle pressure is increased (or lowered) by increasing the internal pressure of 5FL to 15RR, and this vehicle height increase processing is repeated, and when the vehicle height detection value H _i matches the target vehicle height H _S , the vehicle height is increased (or (Decrease) is stopped and the vehicle height is maintained at the target vehicle height.

When the vehicle is started from this stopped state, the neutral voltage V from the longitudinal acceleration sensor 29 according to the longitudinal acceleration is generated.
_The longitudinal acceleration detection value X _G having a positive voltage higher than _N is output. Therefore, in the process of step S17, the actual longitudinal acceleration detection value X _GR becomes a positive value,
The pitch suppression pressure command value PP also becomes a positive value, and regarding the rear wheel side pressure command values P _RL and P _RR , the above-mentioned equation (3) and
As is clear from the equation (4), the vehicle height adjustment pressure command value PH _RL
And PH _RR plus the pitch pressure command value PP, and conversely for the front wheel side pressure command values P _FL and P _FR ,
As is apparent from the equations (1) and (2), the pitch pressure command value PP is _calculated from the vehicle height adjustment pressure command values PH _FL and PH _FR.
Will be subtracted. Therefore, the thrust of the hydraulic cylinders 15RL and 15RR on the rear wheel side increases, and the thrust of the hydraulic cylinders 15FL and 15RR on the front wheel side decreases.
The so-called scut phenomenon in which the rear wheel side sinks due to the acceleration generated in the vehicle can be suppressed and the vehicle body can be maintained in a flat state.

When the vehicle changes from the constant speed running state to the braking state, the longitudinal acceleration sensor 29 detects the longitudinal acceleration detected value X _G which is a positive voltage lower than the neutral voltage V _N according to the deceleration.
Therefore, in contrast to the above, the thrusts of the hydraulic cylinders 15FL and 15FR on the front wheel side are increased, and the thrusts of the hydraulic cylinders 15RL and 15RR on the rear wheel side are decreased. The so-called nose dive phenomenon in which the front wheel side sinks due to the speed can be suppressed to maintain the vehicle body in a flat state.

When the vehicle shifts from the straight traveling state to the left (or right) turning state, the lateral acceleration sensor 28 outputs a lateral acceleration detection value Y _G having a positive voltage higher (or lower) than the neutral voltage V _N. Therefore, the actual lateral acceleration detection value Y _GR calculated in step S8 becomes a positive (or negative) value,
In response to this, the roll suppression pressure command value PL is positive (or negative)
The right hydraulic cylinders 15FR and 15FR
Thrust of RR is increased (or decreased) and thrust of left hydraulic cylinders 15FL and 15RL is decreased (or increased).
Thus, the roll of the vehicle body can be suppressed and the vehicle body can be maintained in a flat state.

By the way, when the vehicle is turning right or is traveling straight ahead, for example, a disconnection occurs in the lateral acceleration sensor 28,
When the lateral acceleration detection value Y _G output from now on becomes zero,
The actual lateral acceleration detection value Y _{GR (n)} calculated in step S8 becomes “−Y _G0 ”, which is a value indicating a sharp left turn state. Therefore, the determination result of step S11 is | Y _{GR (n)} −Y
_{Since GR (n-1)} |> ε, the process proceeds to step S12, the abnormality flag F _A is set to "1", and then the process proceeds to step S13 to calculate the lateral acceleration detection value Y for calculation.
_The previous actual lateral acceleration detection value Y _{GR (n-1)} is adopted as _GO . As a result, the roll suppression pressure command value PL calculated in step S15 is held at a value immediately before the lateral acceleration sensor 28 enters the abnormal state. Therefore, when the vehicle continues to turn right, the hydraulic cylinders 15FL to 15FL
Since the internal pressure of the RR does not fluctuate, the vehicle body can be maintained in a substantially flat state and the steering stability can be improved.

After that, the abnormality flag F_AIs set to “1”
Since it has been registered, steps S10 to S
22 will be moved to the previous calculation lateral acceleration detection
Value Y _{GR (n-1)}The lateral acceleration detection value Y for this calculation_{GR (n)}When
As shown in Fig. 8, the actual lateral acceleration is
Detection value Y_{GR (n)}Lateral acceleration detection regardless of changes in
Value Y_{GO (n)}Is fixed to the value just before the abnormal state, and
Keeps the vehicle in a substantially flat state by maintaining the control state of
can do.

As described above, according to the first embodiment, when the lateral acceleration sensor 28 has an abnormal state, the actual lateral acceleration detection value Y _GR immediately before the abnormal state is held. It is possible to improve the steering stability without causing a change in the posture of the vehicle body due to the abnormality of 28. In the first embodiment described above, the case where the present invention is applied to the active suspension has been described.
The air suspension is not limited to this,
The present invention can be applied to any suspension, such as a semi-active suspension, that can change the roll, pitch, damping at bounce, and rigidity. Among these, as the suspension that can change the roll rigidity, the roll rigidity variable stabilizer shown in FIG. 9 can be applied. This roll rigidity variable stabilizer is connected to a lower arm 41 that constitutes the left and right wheel side members 14, and has a connecting actuator 43 attached at one end via a bush 42, and left and right wheels attached to the other end of the connecting actuator 43. And a stabilizer 44 extending between the side members 14. Here, the connecting actuator 43 is a cylinder tube 4 whose lower end is attached to the lower arm 41 via a bush 42.
3a and the inside of this cylinder tube 43a
b and a piston 43d that defines the lower pressure chamber 43c, and a stabilizer 4 connected to the piston 43d and provided at the upper end.
3 port 2 position electromagnetic directional control valve 43h inserted in a communication passage 43g that externally connects the piston rod 43f to which the end portion of 4 is attached via a bush 43e and the upper pressure chamber 43b and the lower pressure chamber 43c. And the electromagnetic directional control valve 43h controls the lateral acceleration detection value Y _{G of the} lateral acceleration sensor 28.
Is switched and controlled by the exciting current from the controller 45 to which is input. The electromagnetic directional control valve 43h is set to P
Port is to lower pressure chamber 43c, Port A is to upper pressure chamber 43b
In addition, the B port is connected to the accumulator 46, the upper pressure chamber 43b and the lower pressure chamber 43c communicate with each other at the normal position where the exciting current is not supplied, and the accumulator 46 is connected to these communicating passages. In this state, an exciting current having a predetermined value is supplied to switch to the offset position. In this state, the upper pressure chamber 43b and the lower pressure chamber 43c are shut off, and the accumulator 46
It becomes the state which separated.

Then, the controller 45 calculates the actual lateral acceleration detection value Y _GR based on the lateral acceleration detection value Y _G of the lateral acceleration sensor 28, and the absolute value of this actual lateral acceleration detection value Y _GR is a predetermined threshold value Y _TH. It is determined whether or not the above, and | Y _GR | <
When Y _TH , the supply of the exciting current to the electromagnetic directional control valve 43h is cut off, when | Y _GR | ≧ Y _TH , an exciting current of a predetermined value is output to the electromagnetic directional control valve 43h, and the first Similar to step S11 of the embodiment, it is determined whether or not the lateral acceleration sensor 28 is abnormal based on the actual lateral acceleration detection value Y _{GR, and} when it is determined that the lateral acceleration sensor 28 is abnormal, the excitation is performed. Maintain the current output status to the previous status.

Therefore, when the vehicle is traveling straight ahead and the lateral acceleration detection value Y _{G of the} lateral acceleration sensor 28 is the neutral voltage V _N , | Y _GR | <Y _TH is established and the electromagnetic directional control valve 43h is operated. Since no exciting current is supplied, the electromagnetic directional control valve 43h is in the normal position. For this reason,
Since the upper pressure chamber 43b and the lower pressure chamber 43c of the connecting actuator 43 are in communication with each other and the accumulator 46 is connected to the communication passage, the piston 43d is in a freely movable state, and the lower arm 41 and the stabilizer are connected. 44 and 44 are separated, and the roll rigidity becomes small. At this time, when the road surface vibration input from the wheel is transmitted to the connecting actuator 43, the vertical movement of the cylinder tube 43a causes a pressure increase in the lower pressure chamber 43c (or the upper pressure chamber 43b), and the increased amount is the communication passage. 43
However, since the pressure fluctuation is absorbed by the accumulator 46, it is possible to prevent the vibration input from the road surface from being transmitted to the vehicle body side member and to secure a good riding comfort. .. From this straight traveling state, the vehicle turns to generate a lateral acceleration in the vehicle body, and the absolute value of the actual lateral acceleration detected value Y _GR based on the lateral acceleration detected value Y _G output from the lateral acceleration sensor 28 is a predetermined threshold value. When it becomes Y _TH or more, an exciting current of a predetermined value is supplied from the controller 45 to the electromagnetic directional control valve 43h, so that the electromagnetic directional control valve 43h is switched to the offset position. Therefore, the lower pressure chamber 43b and the upper pressure chamber 4 of the connecting cylinder 43 are
The communication passage 43g between the 3c is closed and the accumulator 46 is also disconnected, so that the sliding of the piston rod 43f with respect to the cylinder tube 43a is stopped and the cylinder tube 43a and the piston rod 43f are stopped.
Are integrated, the roll rigidity of the stabilizer 44 is increased, the roll of the vehicle body can be suppressed, and the anti-roll effect can be exhibited.

In this state, when the lateral acceleration sensor 28 becomes abnormal, the controller 45 causes the first
Since the same abnormality determination as in step S11 of the embodiment is performed,
Since the actual lateral acceleration detection value immediately before the abnormality is adopted and the processing is continued, the anti-roll effect can be continuously exerted and the steering stability can be improved. Next, a second embodiment of the present invention will be described with reference to FIG.

In the second embodiment, when the lateral acceleration sensor 28 is in an abnormal state, the actual lateral acceleration detection value Y _{GR (n-1)} immediately before the abnormality is obtained as the calculation lateral acceleration detection value Y _GO. This state is maintained, and after this state is continued for a predetermined time, the calculation lateral acceleration detection value Y _GO is gradually returned to zero. That is, as shown in FIG. 10, when the determination result of step S10 in the flowchart of FIG. 7 in the first embodiment is that the abnormality flag F _A is set to “1”, the process proceeds to step S23 and the predetermined operation is performed. It is determined whether or not time has elapsed, and when the predetermined time has not elapsed,
When the process proceeds to step S22 and a predetermined time has elapsed, the process proceeds to step S24, and it is determined whether or not the calculation lateral acceleration detection value Y _GO is within a predetermined dead zone centered on zero. _{If GO} |> α, step S
25, it is determined whether or not the calculated lateral acceleration detection value Y _GO is positive. If Y _GO > 0, step S2
6 proceeds to, step S15 described above after updating stores a value obtained by subtracting a predetermined value ΔY from calculation lateral acceleration detected value Y _GO at that time as the lateral acceleration detection value Y _GO for the new calculation
When Y _GO <0, the process proceeds to step S27, and a value obtained by adding the predetermined value ΔY to the calculation lateral acceleration detection value Y _GO at that time is added to the new calculation lateral acceleration detection value Y _GO.
After updating and storing as, the process proceeds to step S15,
Further, when the determination result of step S24 is | Y _GO | ≦ α, the process directly proceeds to step S15.

According to the second embodiment, when the lateral acceleration sensor 28 has an abnormal condition such as a wire breakage or a power supply abnormality, the process proceeds from step S11 to step S12 and the abnormality flag is detected as in the first embodiment. F _A is set to "1", and then the process proceeds to step S13, where the previous actual lateral acceleration detection value Y _{GR (n-1)} is set as the calculation lateral acceleration detection value Y _GO.
) Is adopted and the roll restraining pressure command value PL is calculated based on the calculated lateral acceleration detection value Y _GO , it is possible to improve the steering stability when an abnormality occurs in the lateral acceleration sensor 28.

Then, a predetermined time has passed from the time of occurrence of the abnormality.
After that, the process moves from step S23 to step S24 to perform the performance.
Calculated lateral acceleration value Y_GOWhether is in the dead zone including zero
If it is within the dead zone, step as it is.
Shift to S15 to calculate the roll suppression pressure command value PL
If it is out of the dead zone, the process proceeds to step S25.
Then, the lateral acceleration detection value Y for calculation at that time_GOIs positive
Move to step S26 (or S27) depending on whether it is negative
Lateral acceleration detection value Y for calculation_GOSubtract a predetermined value ΔY from
The calculated (or added) value is the new lateral acceleration detection value Y for calculation._GO
After updating and storing as
The pressure suppression pressure command value PL is calculated. As a result, lateral acceleration
The predetermined time has passed since the
After that, the lateral acceleration detection value Y for calculation is sequentially incremented by a predetermined value ΔY._GO
Is decreased, and the lateral acceleration detection value Y for calculation is decreased. _GOTo reset to zero
The vehicle has returned from the turning state to the straight-ahead state.
Sometimes it can prevent the car body from leaning.
Wear.

Next, a third embodiment of the present invention will be described with reference to FIGS. The third embodiment shows a case where the present invention is applied to an active suspension having an encapsulation mechanism for enclosing the pressure of a fluid cylinder when not controlled. Figure 1
3, 80FL to 80RR are hydraulic cylinders inserted between the wheels and the vehicle body, and 81FL to 81RR are hydraulic cylinders 80.
A pressure control valve for controlling the operating pressure of FL to 80RR, and 82 is a hydraulic pressure source. The hydraulic pressure source 82 includes a supply pipe 83 and a return pipe 84.
Are connected to the supply and return ports of the pressure control valves 81FL to 81RR, respectively, and the output ports of the pressure control valves 81FL to 81RR are connected to the cylinder chamber via the output pipe 85. Pilot pressure operated type operation check valves 86FL to 86RR as opening / closing valves are inserted in each output pipe 85, and the pilot ports of these check valves 86FL to 86RR are connected by a pipe 87 to a 3-port / 2-position electromagnetic switching valve 8
8 cylinder ports A communicate with each other. Solenoid switching valve 8
The pump port P and the tank port T of 8 are the supply pipes 83
And the return pipe 84.

Here, each of the hydraulic cylinders 80FL to 80RR is composed of a single-acting cylinder, and the cylinder tube 80a has a cylinder chamber L defined by the piston 10b, and the lower end of the cylinder tube 80a is a wheel side member. The upper end of the piston 6 degrees 80c is attached to the vehicle body side member. Each cylinder chamber L is connected to a small-capacity sub-accumulator 93 via a throttle valve 92, and absorbs hydraulic vibrations in the unsprung resonance frequency range that cannot be responded by the pressure control valves 81FL to 81RR.

Among the output pipes 85 connected to the hydraulic cylinders 80FL to 80RR, a midway position between the operation check valve 86FL and the hydraulic cylinder 18FL and a midway position between the operation check valve 86FR and the hydraulic cylinder 80FR in the front wheel side pipe. Are connected to each other by a communication pipe 94F, and two diaphragms 95FL,
95 FR is inserted in series. Similarly, a midway position between the operate check valve 86RL and the hydraulic cylinder 80RL and a midway position between the operate check valve 86RR and the hydraulic cylinder 80RR in the pipe on the rear wheel side are connected to each other by a communication pipe 94R. Two diaphragms 95RL and 95RR are inserted in series in the middle of the line. Further, the position between the throttles 95FL and 95FR in the front wheel side communication pipe 94F and the position between the throttles 95RL and 95RR in the rear wheel side communication pipe 94R are connected to each other through another communication pipe 96, and this communication is performed. A diaphragm 97 is inserted in the middle of the tube 96. Here, diaphragms 95FL and 95FR and 95RL and 9
The damping constant of 5RR is set to a value at which the hydraulic pressures of the left and right wheels hardly interfere during roll control, and the damping constant of the throttle 97 is set to a value at which hydraulic pressures of the front and rear wheels hardly interfere during pitch control. There is.

The hydraulic pressure source 82 includes a reservoir tank 82a for storing hydraulic oil, a hydraulic pump 82b for reducing the rotational drive of the vehicle engine, a relief valve 82c for setting a predetermined line pressure, and a main pulsation absorbing main body. Accumulator 8
2d and an oil cooler 82e that cools the return hydraulic oil. The supply pipe 82S of the hydraulic power source 82 is connected to the input side ports of the pressure control valves 81FL to 81RR and the pump port P of the electromagnetic directional control valve 88. The return pipe 82R is connected to the return side ports of the pressure control valves 81FL to 81RR and the tank port T of the electromagnetic directional control valve 88.

Further, operate check valves 86FL-8FL
For each of 6RR, the pilot port has an electromagnetic directional control valve 88
Of the pressure control valves 81FL to 81RR and output ports thereof to the hydraulic cylinders 80FL to 80RR, respectively, and the pilot pressure P _P supplied to the pilot port is preset. When the relief pressure is higher than the atmospheric pressure P _P0 or less (P _P ≦ P _P0 ), it is in the fully closed state, and when P _P > P _P0, it is in the fully open state.

Then, the acceleration detection value Y _G of the acceleration sensor 28 and the switch signal OP of the switch 86A for detecting the open / closed state of each of the operation check valves 86FL to 86RR are input to the controller 91, and the controller 91 described above in the first embodiment. The roll restraining pressure command value PL, the vehicle height adjusting pressure command values PH _{FL to} PH _RR , and the pitch restraining pressure command value PP are calculated by performing the same processing as in step S1 to calculate the pressure command values P _{FL to} P _RR to the pressure control valve 81FL. .About.81RR, and also outputs a switching signal CS for controlling switching of the electromagnetic directional control valve 88.

Next, the operation of this embodiment will be described. First, the processing of FIG. 12 is executed. The controller 91 starts up when the power is turned on, reads a switch signal from a key switch (not shown) in step S31 in the figure, determines whether or not the ignition switch is on in step S32, and steps S31 and S32 until the engine is turned on. The process is repeated to wait. If it is determined in step S32 that the engine is on, the process proceeds to step S33, and the pressure command values P _{FL to} P _RR given to the pressure control valves 81 _{FL to} 81 _RR are initialized to P _{FL to} P _RR = 0. ..

Then, the process proceeds to step S34, and the switch 8 provided in each of the operation check valves 86FL to 86RR.
The switch signals OP from all 6A are read, and the process proceeds to step S35. In step S35, all the switch signals OP input in step S34 are turned off, that is, 4
It is determined whether or not each of the operation check valves 86FL to 86RR is in the initial starting state in which the closed state is maintained. If the result of determination in step S35 is the initial state of starting, the process proceeds to step S36, and the switching control signal CS supplied to the electromagnetic switching valve 88 is turned off, and then steps S37, S.
38 is performed. In step S37, command values P _{FL to} P _FL
In order to gradually increase _RR , a predetermined value ΔP _S is added to each of the current command values P _{FL to} P _RR and new command values P _{FL to} P _RR are added.
Is calculated, and the command values P _{FL to} P _RR calculated in step S37 are output in step S38. As a result, the command currents i corresponding to the command values P _{FL to} P _RR are supplied to the pressure control valves 81 _{FL to} 81 _RR . After that, the process returns to step S34,
The above process is repeated.

During the process, the operating check valve 86
If all of FL to 86RR are in the open state and it is determined in step S35 that the initial starting state has passed, step S35
39 and S40 are processed. In step S39, the switch signal from the key switch is read, and in step S40
Determines whether the engine is on. When it is confirmed that the ignition switch is turned on, that is, the engine is turned on by this determination, the process proceeds to step SH, and after the process for calculating the vehicle height pressure command values PH _{FL to} PH _RR is performed,
The process proceeds to step S7 described above.

Then, in the processing of steps S7 to S14,
While performing the abnormality determination process similar to that of the first embodiment, and when the lateral acceleration sensor 28 is normal, the process proceeds to step S14 through steps S7 to S11, and the current actual lateral acceleration detection value Y _{GR (n) is obtained.} Is calculated lateral acceleration detection value Y _GO
When the lateral acceleration sensor 28 is in the abnormal state, the process proceeds to step S41 to turn on the switching control signal CS and then to step S15.
After shifting from step S13 or S22 to step S42, the switching control signal CS is turned off, and then step S
When the engine is in the ON state as a result of the determination in step S40, the process also proceeds to step S42.

It is now assumed that the vehicle is stopped with the engine stopped. In this stopped state, the power is off, and the switching control signal CF for the electromagnetic directional control valve 88 is OFF, so the electromagnetic directional control valve 88 is in the non-energized position, that is, the open state between the cylinder port A and the tank port T. I am maintaining. As a result, the pilot pressure of each of the operation check valves 86FL to 86RR is also atmospheric pressure, and the check valves 86FL to 86RR are
Is closed and the output pipe 85 is cut off. That is,
The operating pressures of the hydraulic cylinders 80FL to 80RR are balanced and enclosed by the four wheels.

From this state, when the key switch is rotated to the accessory position, control by the controller 91 is started, and when the key switch is further rotated to the ignition on position, the engine is started. As a result, the hydraulic pump 82
Since b starts to be driven, the pump discharge pressure immediately rises to a specified value, and the line pressure set by the relief valve 82c is supplied to the pressure control valves 81FL to 81RR.

In the initial state of engine startup, the controller 91 determines the operating conditions of the operation check valves 86FL to 86RR based on the switch signal OP (see steps S34 and S35 in FIG. 12), and the electromagnetic switching valve 88 is normally operated when it is not energized. The position is maintained (see step S36 in FIG. 12). However, the operation check valves 86FL-86
Since the pilot pressure of RR is still atmospheric pressure, the operating check valves 86FL to 86RR do not operate, and only function as a check valve with a small amount of leak to seal the cylinder operating pressure. Along with this, the controller 91
Gradually increases the command current i to the pressure control valves 81FL to 81RR from the low pressure side (steps S33 and S3 in FIG. 12).
7, S38), the control pressure P _C output by the pressure control valves 81FL to 81RR also smoothly rises according to the command current i. Then, the control pressure> operate check valve 86FL~86RR when it becomes a sealed cylinder pressure are opened, with the cylinder pressure encapsulation is released, enclosed cylinder pressure and the control pressure P _C is connected smoothly.

For this reason, for example, due to a long-term stopped state,
Even if the enclosed cylinder pressure is lower than the value at the time of the previous stop due to the cylinder leak, the state in which the vehicle height suddenly increases when the engine is started is accurately eliminated, and the occupant does not feel useless. In this way, when the control pressure P _C gradually rises and all the operation check valves 86FL to 86RR of each wheel are opened, the controller 91 exits the initial state of engine start (see step S35 in FIG. 12) and performs normal control. Get into action.

In this normal control state, assume that the suspension system is normal and the engine is running (see FIG. 12).
(See steps S39 and S40), the switching control signal CS for the electromagnetic switching valve 88 is turned on (FIG. 12, step S4).
1). As a result, the electromagnetic switching valve 88 connects the switching position at the time of energization, that is, the cylinder port A to the pump port P, so that the pressure of the pilot pressure pipe 87 of the operating check valves 86FL to 86RR is the line pressure of the supply pipe 85 (supply). Pressure), and therefore the operation check valves 86FL to 86RR are forcedly opened, and the cylinder pressure is controlled by the control pressure P _C.

Then, the active posture control for suppressing the swing of the vehicle body is made possible in accordance with the detected lateral acceleration value Y _G (see steps S7 to S20 in FIG. 12). That is, when the active control is performed, the cylinder pressure on the outer wheel side during turning is increased compared to when it is straight ahead, and the cylinder pressure on the inner wheel side is reduced compared to when it is straight ahead, so an anti-roll moment proportional to the inertial force is generated. Occurs, and the roll angle falls within the target value.

During this roll control, the lateral acceleration sensor 28
If an abnormal state occurs in step S1 as described above,
Shifts from 1 to step S12, while set to "1" abnormality flag F _A, the actual lateral acceleration detected value of the previous Step S13 Y _{GR (n-1)} the calculation lateral acceleration detected value Y _GO
Is stored as an update, and the anti-roll control is continued by calculating the roll suppression pressure command value PL based on the calculated lateral acceleration detection value Y _GO , and at the same time, step S4.
In the processing of 2, the control signal CS for the electromagnetic directional control valve 88
Is turned off, the electromagnetic switching valve 88 is switched to the normal position, and the pilot pressure pipe 87 and the return side pipe 82
R is communicated. As a result, the pilot pressures of all the operation check valves 86FL to 86RR become almost atmospheric pressure, so that the check valves 86FL to 86RR are closed in an instant after an abnormality occurs. Due to this closing operation, the hydraulic cylinder 8
The operating pressure at the time of occurrence of an abnormality of 0FL to 80RR is temporarily confined, and thereafter, the pressure of the cylinder chamber L confined to a high pressure among the cylinder chambers L of the hydraulic cylinders 80FL to 80RR is gradually reduced to 95FL to 95RR. And 97 to the lower cylinder chamber L. Therefore,
When the vehicle returns from the turning state to the straight running state,
The pressure of each hydraulic cylinder 80FL-80RR is equalized,
The posture of the vehicle body is kept flat.

Further, the supply line 8 is provided by the electromagnetic switching valve 88.
Even in the normal control state in which the 2S and the pilot pressure pipe 87 are in communication, if the supply pressure falls below the pilot pressure reference value P _{P0 of the} operating check valves 86FL to 86RR due to the failure of the hydraulic pressure source 82. , Operate check valves 86FL to 86RR are automatically closed. Because of this
Even when an abnormal state of the hydraulic pressure supply system occurs, a suboptimal suspension state can be obtained relatively well as described above.

Further, even when the suspension system is normal, when the vehicle is stopped and the engine rotation is stopped, this state is detected and the working pressure is sealed in the same way as when an abnormality occurs. As a result, a decrease in vehicle height due to engine stop is reliably prevented, and the operating pressure when the engine is off is held for a long time by the operation check valves 86FL to 86RR, and the vehicle height value is maintained at a good level.

In such an operation, a pilot pressure operated type switching valve is used as the on-off valve, and the pilot pressure of each of the switching valves is collectively switched by one solenoid valve. Therefore, the solenoid valve is used as the on-off valve for each wheel. Compared to the case of using, the number of electromagnetic solenoids is reduced, and the pilot pressure switching solenoid valve need only have a capacity to form pilot pressure (low pressure), so it is compact as a whole and saves space. Can be promoted and the manufacturing cost can be reduced. At the same time, power consumption is reduced and the burden on the battery can be reduced.

[0059] Incidentally, in the third embodiment, configured for detecting the opening operation of the operate check valve 86FL~86RR is not limited to the configuration to detect by the switch 86A, for example, a control pressure P _C> cylinder pressure The stroke check of the hydraulic cylinders 80FL to 80RR may be performed by detecting the stroke increase of the hydraulic cylinders 80FL to 80RR due to opening of the operation check valves 86FL to 86RR and slight increase of the cylinder pressure.

Further, the on-off valve of the third embodiment is not limited to the structure of the operating check valve described in the above-mentioned embodiment, and for example, the pilot operated spool type switching valve described in JP-A-63-106132. Can also be used. Furthermore, in the third embodiment described above, the case where the operating check valve is applied has been described, but the present invention is not necessarily limited to the configuration described in the above embodiment, and for example, a check valve including a poppet valve and a first spring, and a pilot pressure are used. A pilot piston for receiving the pressure and a push mechanism having a second spring against the piston, the pilot piston being poppet when the force received from the pilot pressure by the pilot piston is larger than the second spring. It is also possible to push the valve and open both ports that were closed by the pilot valve until then.

Furthermore, in each of the above-described embodiments, the case of detecting the abnormal state of the lateral acceleration sensor 28 has been described, but the present invention is not limited to this, and not only the acceleration sensor such as the longitudinal acceleration sensor and the vertical acceleration sensor but also the acceleration sensor. It is also possible to detect an abnormal state of a sensor such as a steering angle sensor, a vehicle speed sensor, or a vehicle height sensor that detects a running state of the vehicle. If the abnormal state occurs, the previous detection value can be maintained. Good.

Furthermore, in each of the above embodiments, the case where the working oil is applied as the working fluid has been described, but the present invention is not limited to this, and for example, air may be used. The controller may be started in the ignition on state. Further, the controller may be composed of a logic circuit and an analog electronic circuit other than the microcomputer.

[0063]

As described above, according to the vehicle suspension of the present invention, the abnormality detecting means for detecting the abnormality of the traveling state detecting means for detecting the traveling state of the vehicle, and the abnormality detecting means for detecting the abnormality. Since the detection value fixing means for fixing the detected traveling state value of the traveling state detection means to the immediately preceding traveling state detection value when detected is provided, the control means immediately before the traveling state detection means becomes abnormal. It is possible to control an actuator that suppresses swings of the vehicle such as roll motion, pitch motion, and bounce motion based on the traveling state detection value, and prevent changes in the control mode of the vehicle due to an abnormality in the traveling state detection means. As a result, it is possible to obtain the effect of ensuring a stable running state.

[Brief description of drawings]

FIG. 1 is a diagram corresponding to the claims of the present invention.

FIG. 2 is a schematic configuration diagram showing an overall configuration of a first embodiment of the present invention.

FIG. 3 is a characteristic diagram showing a relationship between an exciting current of a pressure control valve and a control pressure.

FIG. 4 is a characteristic diagram showing output characteristics of a lateral acceleration sensor.

FIG. 5 is a characteristic diagram showing an output characteristic of a longitudinal acceleration sensor.

FIG. 6 is a block diagram showing an example of a controller.

FIG. 7 is a flowchart showing an example of a processing procedure of a controller.

FIG. 8 is a characteristic diagram showing changes in the detected actual lateral acceleration value and the calculated actual lateral acceleration detected value.

FIG. 9 is a schematic configuration diagram showing an example of a roll rigidity variable stabilizer applicable to the present invention.

FIG. 10 is a flowchart showing an example of a processing procedure in the second embodiment of the present invention.

FIG. 11 is a schematic configuration diagram showing a third embodiment of the present invention.

FIG. 12 is a flowchart showing a processing procedure of a controller in the third embodiment.

[Explanation of symbols]

 11FL-11RR Active suspension 15FL-15RR Hydraulic cylinder 17FL-17RR Pressure control valve 28 Lateral acceleration sensor 29 Front-back acceleration sensor 30FL-30RR Height sensor 32 Microcomputer 43 Connection actuator 44 Stabilizer 80FL-80RR Hydraulic cylinder 81FL-81RR Pressure control valve 82 Hydraulic power source 86FL to 86RR Operate check valve 91 Controller 95FL to 95RR, 97 Throttle

Claims (1)

[Claims] 1. An actuator for suppressing swinging of a vehicle such as a roll motion, a pitch motion, a bounce motion, a running state detecting means for detecting a running state of the vehicle, and a running state detection value of the running state detecting means. In a vehicle suspension provided with a control means for controlling the actuator by means of an abnormality detection means for detecting an abnormality of the traveling state detection means, and a traveling state of the traveling state detection means when an abnormality is detected by the abnormality detection means. A vehicle suspension characterized by comprising detection value fixing means for fixing the detection value to the immediately preceding traveling state detection value as a state detection value.