JP3075133B2 - Suspension control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension control apparatus for performing open loop control of suspension characteristics such as damping force using a step motor.

[0002]

2. Description of the Related Art A conventional suspension control device is disclosed in, for example, Japanese Patent Application Laid-Open No. 3-42319. In this conventional example, by inputting a control signal,
A shock absorber that can change the extension-side damping force and the compression-side damping force to at least a low damping force and a high damping force by adjusting the throttle opening with a rotary actuator such as a step motor, and a spring that measures the sprung speed. An upper speed measuring means, a relative speed measuring means for measuring a relative speed between sprung and unsprung, a sign judging means for judging whether or not the sign of the sprung speed and the sign of the relative speed are coincident; When they match and the sign of the relative speed is positive, the extension side is set to high damping force and the compression side is set to low damping force.When both signs match and the sign of the relative speed is negative, A control signal output means for outputting a control signal for making the damping force low on the pressure side and a high damping force for the pressure side, and outputting a control signal for making both the compression side and the compression side have a low damping force when both codes do not match. It has the structure provided with.

[0003]

However, in the above-mentioned conventional suspension control device, the damping force is varied by adjusting the aperture of the throttle by the rotary actuator which is controlled by the open loop. It is highly likely that the control origin will be deviated due to disturbance or the like, and if left unchecked, the control performance of the actuator will be reduced. Therefore, it is necessary to calibrate, that is, initialize, the control origin of the rotary actuator.

In performing this initialization, it is usually necessary to bring the engaging piece, which rotates integrally with the rotary actuator, into contact with the stopper representing the control origin several times, and the engaging piece vigorously contacts the stopper. When this is done, the engagement piece separates from the stopper due to the reaction and the accuracy of control origin calibration is reduced, so that the speed at the time of contact with the stopper is reduced, so that the initialization execution time is relatively long. .

On the other hand, since the drive torque of the step motor is affected by the power supply voltage, the initialization is started when the power supply voltage is equal to or higher than a preset initialization start voltage, and after the initialization is started, the power supply voltage is lower than the initialization start voltage. Is satisfied, it is determined that the initialization is inaccurate, and the initialization is executed again.

For this reason, in the prior art, when the initialization is started in a state where the battery voltage is low, the four-wheel actuators are simultaneously driven, so that there is a high possibility that the power supply voltage becomes lower than the initialization start voltage. There is an unsolved problem that the initialization is repeatedly started and stopped, and the initialization cannot be completed forever.

Therefore, the present invention has been made in view of the above-mentioned unsolved problems of the prior art, and determines whether or not the initialized state can be maintained even when the power supply voltage is reduced during the initialization. Accordingly, it is an object of the present invention to provide a suspension control device that can prevent the start and stop of the initialization from being repeated and can complete the initialization early.

[0008]

In order to achieve the above object, a suspension control device according to the first aspect of the present invention comprises:
As shown in the basic configuration diagram of FIG. 1, the suspension is controlled by rotating a valve body by a step motor interposed between a vehicle body-side member and a wheel-side member and driven in accordance with an input control signal. A suspension control device comprising: an actuator capable of individually controlling characteristics; and control means for detecting a change in posture of the vehicle body and outputting the control signal corresponding to the detected change in posture to the step motor to perform open-loop control. A power supply voltage detecting means for detecting a power supply voltage to be supplied to the stepping motor; and a control means when a power supply voltage detection value of the power supply voltage detecting means reaches a preset voltage for performing initialization of a control system set in advance. Initialization executing means for performing initialization of the electronic device, and the power supply after the initialization is started by the initialization executing means. It is characterized in that the voltage detection value and a initializing stop means for stopping the initialization of the initialization execution means when the sum of time equal to or less than a lower monitored voltage than the set voltage is equal to or larger than a set value.

According to a second aspect of the present invention, in the suspension control apparatus according to the first aspect of the present invention, when the initialization execution means determines that the vehicle speed is equal to or higher than the set vehicle speed and the power supply voltage detection value is equal to or higher than the set voltage. It is characterized in that the control means is initialized. Further, in the suspension control device according to a third aspect of the present invention, in the first or second aspect of the present invention, the initialization stopping means has a counter for updating a count value while the power supply voltage detection value is equal to or less than the monitoring voltage, The initialization is stopped when the count value of the counter reaches a set value.

[0010]

According to the first aspect of the present invention, when the power supply voltage becomes equal to or higher than the set voltage by the initialization executing means, initialization of the control system is started, and during this initialization, the power supply voltage falls to a monitor voltage lower than the set voltage. Then, the decrease time is measured by the initialization canceling means, and when the sum of the decrease times is less than the preset value, the initialization by the initialization execution means is continued, and the sum of the decrease times becomes equal to or more than the set value. At first, it is determined that the initialization is defective, and the initialization of the initialization executing means is stopped.

According to the second aspect of the present invention, the initialization is started when the vehicle speed is equal to or higher than the set vehicle speed and the detected power supply voltage is equal to or higher than the set voltage by the initialization executing means, thereby generating a step motor generated at the time of initialization. It is possible to prevent the noise and vibration caused by the drive noise and the engagement piece from coming into contact with the stopper by driving noise or the like, thereby preventing the occupant from feeling uncomfortable.

Further, in the invention according to claim 3, the initialization canceling means updates the count value of the counter when the detected power supply voltage value is less than the monitor voltage, thereby returning the power supply voltage to the monitor voltage or more. Sometimes, the count value can be held, and the sum of times during which the voltage is equal to or lower than the monitoring voltage can be easily detected.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a schematic configuration diagram showing one embodiment of the present invention, in which variable damping force shock absorbers 3FL to 3RR as actuators constituting a suspension device are arranged between the wheels 1FL to 1RR and the vehicle body 2, respectively. The step motors 41FL to 41RR for switching the damping force of these variable damping force shock absorbers 3FL to 3RR are controlled by a control signal from a controller 4 described later.

Variable damping force shock absorber 3FL-3RR
Is a twin-tube gas-filled strut type having a cylinder tube 7 composed of an outer cylinder 5 and an inner cylinder 6 as shown in FIGS. 8 define upper and lower pressure chambers 9U and 9L. 4 to 7, the piston 8 has a cylindrical lower half 11 having a sealing member 9 molded on the outer peripheral surface thereof in sliding contact with the inner cylinder 6 and having a center opening 10 on the inner peripheral surface. The lower half 11 has an upper half 12 fitted therein.

The lower half body 11 has an extension oil passage 13 penetrating vertically and a sealing member 9 extending downward from the upper surface.
The hole 14 a having a diameter larger than that of the extension-side oil flow path 13 and extending from the outer peripheral surface of the cylindrical body 11 to the hole 14.
a, a pressure-side oil flow path 14 formed of a hole 14b drilled in communication with the bottom of the hole a, annular grooves 15U, 15L formed at the upper and lower open ends of the central hole 10, and formed on the upper surface side. A long groove 16 communicating with the annular groove 15U and the expansion-side oil flow path 13 and a long groove 17 formed on the lower surface side and communicating with the annular groove 15L are formed. The long groove 17 is closed by the extension-side disk valve 18, and the upper end side of the compression-side oil flow path 14 is closed by the compression-side disk valve 19.

The upper half 12 has a small-diameter shaft 21 inserted into the center opening 10 of the lower half 11 and
The lower end face of the small-diameter shaft portion 21 is formed at the center of the small-diameter shaft portion 21 and the large-diameter shaft portion 22. 23a extending from the side to the middle of the large-diameter shaft portion 22, and a hole 23b communicating with the upper end of the hole 23a and having a smaller diameter than the hole 23a.
And a hole 23c having a larger diameter than the hole 23c communicating with the upper end side of the hole 23b. The through hole 23 is formed at a position facing the annular grooves 15U and 15L of the small diameter shaft 21 respectively. Pair of through holes 24 penetrating the inner peripheral surface side in the direction
a, 24b and 25a, 25b are drilled, and the upper end side of the hole 23a of the large-diameter shaft portion 22 is connected to the arc-shaped groove 2 communicating therewith.
6 is formed, and an L-shaped pressure-side oil flow path 27 communicating with the arc-shaped groove 26 and the lower end face is formed.
Is blocked by

The lower half 11 and the upper half 12 are positioned below the lower half 11 of the small-diameter shaft 21 with the small-diameter shaft 21 inserted into the central opening 10 of the lower half 11. The nut 29 is screwed into the lower end protruding from the nut, and the nut 29 is tightened to be integrally connected. Further, a cylindrical valve body 31 whose upper end is closed in a hole 23a of the upper half body 12 and constitutes a variable throttle is rotatably disposed. As shown in FIG. 4, the upper half 1
2, a through-hole 32 is formed at a position facing the arc-shaped groove 26 of the large-diameter shaft portion 22 so as to reach the inner peripheral surface in the radial direction, and the small-diameter shaft of the upper half body 12 as shown in FIGS. A communication groove 33 is formed in the outer peripheral surface corresponding to the portion between the through holes 24a and 24b of the portion 21 so as to communicate with each other. Further, as shown in FIG.
An elongated hole 34 extending in the axial direction is formed in the outer peripheral surface corresponding to the area between the inner peripheral surface and the inner peripheral surface side.
Then, the positional relationship between the through hole 32, the communication groove 33 and the long hole 34 is selected so as to obtain the damping force characteristic with respect to the position of the valve element 31 shown in FIG. 8, that is, the step angles of the step motors 41FL to 41RR described later. I have.

That is, at the position A in FIG. 8, which is the maximum rotation angle position in the clockwise direction when viewed from the plane, only the through hole 32 communicates with the arc-shaped groove 26 as shown in FIG. Moves downward from the lower pressure chamber 9L through the pressure-side oil flow path 14 to the upper pressure chamber 9U through an orifice formed by the open end and the pressure-side disk valve 19. Channel C
1 through the inner peripheral surface of the valve body 31 from the lower pressure chamber 9L, through the through hole 32, the arc-shaped groove 26, the pressure side oil flow path 27, and through the orifice formed by the opening end and the pressure side disc valve 28. Pressure side flow path C2 shown by a broken line toward the upper pressure chamber 9U.
Is formed and the piston 8 moves upward on the extension side, the orifice formed by the open end and the extension side disc valve 18 from the upper pressure chamber 9U through the elongated groove 16 and the extension side flow path 13. Only the extension side flow path T1 shown by a broken line toward the lower pressure chamber 9L is formed, and a high damping force that rapidly increases in accordance with an increase in the piston speed is generated on the extension side, and is increased on the compression side. Generates a low damping force that increases slightly as the piston speed increases.

As shown in FIG. 5, the valve body 31 is rotated counterclockwise from the position A so that the communication groove 33 of the valve body 31 and the through hole 2 of the small diameter shaft portion 21 are rotated.
4a and 25a are in communication with each other, and the opening area between the communication groove 33 and the through holes 24a and 25a gradually increases as the rotation angle increases. For this reason, as shown in FIG. 5 (a), the elongated groove 16, the annular groove 15U, the through hole 24a, the communication groove 33, the through hole 25a, Passing through the annular groove 15L and the long groove 17, the long groove 1
A flow path T2 is formed toward the lower pressure chamber 9L through an orifice formed by the pressure valve 7 and the pressure-side disk valve 18, and the maximum value of the damping force is increased as shown in FIG.
3 and the through-holes 24a, 25a of the small-diameter shaft portion 21 gradually decrease as the opening area increases, and as shown in FIG. To maintain the formed state, the minimum damping force state is maintained.

Further, when the valve body 31 is rotated counterclockwise as viewed from a plane and becomes near the position B, as shown in FIG. 6, a long hole 34 is formed between the through holes 25a and 25b of the valve body 31.
The communication is established. Therefore, the piston 8
As shown in FIG. 6 (a), the lower side passes through the long groove 16, the annular groove 15U, the through hole 25a, the long hole 34, and the hole 23a in parallel with the flow paths T1 and T2. 9L pressure chamber
Is formed, the extension-side damping force becomes the minimum damping force state, and the hole 23a and the long hole are provided for the movement of the piston 8 on the compression side in addition to the channels C1 and C2. 34, the through-hole 25a, the long groove 1 through the annular groove 15U.
6, the flow path C3 and the hole 23a, the long hole 34, the through hole 25b, the annular groove 15L, the through hole 24b, the communication groove 33,
A flow path C4 that reaches the long groove 16 through the through hole 24a and the annular groove 15U is formed, but maintains the minimum damping force state as shown in FIG.

Further, when the valve element 31 is rotated counterclockwise as viewed from the plane, the elongated hole 34 and the through holes 24b and 25b
And the opening area between the hole 34 and the long hole 34 at the rotation angle θ _B2 is reduced.
7, the opening area between the through hole 32 and the arc-shaped groove 26 gradually decreases from the rotation angle θ _B2 . Therefore, between the rotation angle θ _B2 and the maximum counterclockwise rotation angle θ _C ,
For the movement of the piston 8 on the extension side, the flow path T1 and the flow path T2 coexist, so that the minimum damping force state is maintained. As the opening area between them gradually decreases, the maximum damping force gradually increases, and when the valve body 31 reaches the position C, as shown in FIG. By being in the cutoff state, the flow path from the lower pressure chamber 9L to the upper pressure chamber 9U is only the flow path C1 with respect to the pressure side movement of the piston, and the pressure side is in a high damping force state.

On the other hand, a cylindrical piston rod 35 is fitted into the hole 23c of the upper half body 12, and the upper end of the piston rod 35 projects upward from the cylinder tube 7, as shown in FIG. The upper end side is the vehicle body side member 36.
Is fixed by a nut 39 via rubber bushes 38U and 38L to a bracket 37 attached to the piston rod 35, and the step motors 41FL to 41RR are mounted on the upper end of the piston rod 35 via a bracket 40 by the rotation shaft 41a.
The rotating shaft 41a and the above-described valve element 31 are connected by a connecting rod 42 loosely inserted into the piston rod 35. 43 is a bumper rubber. The lower end of the cylinder tube 7 is connected to a wheel-side member (not shown).

As shown in FIG. 9, a projecting body 44 in the form of a rectangular parallelepiped is provided at the upper end of the valve body 31 so as to rotate the valve body 31 by the rotating shaft 41a of the step motors 41FL to 41RR. It rotates synchronously with the movement. And the upper half 1
A stopper plate 45 is provided in the inner hole of the second receiving body 44, and the pressing body 44 and the stopper plate 45 constitute a stopper mechanism.

Two abutting projections 45a and 45b are provided in the inner hole of the stopper plate 45, and the abutting body 44 is rotated by the rotation shaft 41a of the step motor 41 or the valve body 31. When the valve body 31 rotates to the position A or the position C described above, the two restricting end faces 44a or 44b of the abutment body 44 are brought into contact with the abutment projection 4.
5a or 45b, the valve body 31 is prevented from rotating any further, and the position P of the valve body 31 is shifted to the positive maximum position _PMAX or the negative maximum pressure position (-).
P _MAX ) is used to correct the positional deviation between the rotation angle of the step motor 41 and the position of the valve element 31 by a control origin configuration process, that is, a so-called initialization process, which will be described later.

As shown in FIG. 10, the controller 4 has on its input side an analog voltage that is upwardly positive and downwardly negative according to the vertical acceleration provided on the vehicle body corresponding to each wheel position. Vertical acceleration detection value X _2FL ″
_{FLX 2RR} ″ are connected to vertical acceleration sensors 51FL to 51RR as vertical acceleration detecting means.
A vehicle speed sensor 52 for detecting a vehicle speed is connected, and a step motor 41FL-41RR for controlling the damping force of each of the variable damping force shock absorbers 3FL-3RR is connected to the output side.

The controller 4 includes a battery 5
A stabilized power supply circuit 54, which receives a DC power supply from the power supply 3 and converts it into a control power supply;
5a, output interface circuit 55b, arithmetic processing unit 5
5c, a microcomputer 55 having at least a storage device 55d, an A / D converter 56 for converting a power supply voltage of a battery 53 into a digital value and inputting the digital value to an input interface circuit 55a, and vertical acceleration sensors 51FL to 51FL-5.
The A / D converters 57FL-57RR for converting the detected vertical acceleration values X _2FL ″ _{-X 2RR} ″ of 1RR into digital values and inputting them to the input interface circuit 55a, and converting the vehicle speed detection value V of the vehicle speed sensor 52 into digital values. A / D converter 58 which supplies the data to input interface 55a, and outputs each step motor 41 output from output interface circuit 55b.
A step control signal for FL to 41RR is input, and is converted into a step pulse to convert each step motor 41FL to 41RR.
The motor drive circuits 59FL to 59RR for driving the 41RR are provided.

Here, the arithmetic processing unit 55c of the microcomputer 55 calculates the detected vehicle vertical acceleration values X _2FL ″ to X _2FL ″ to X
Calculating a vehicle body vertical velocity X _2FL '~X _2RR' by integrating the _2RR ", calculates the extension phase and compression phase position P _T and P _C on the basis of the vehicle body vertical velocity, these and the current position P
A damping force control process of calculating a difference value from _P and outputting a step control amount corresponding to the calculated value to the motor drive circuits 59FL to 59RR is performed, and when the ignition switch is turned on and the vehicle speed detection value V the preset set speed V flat road surface and the road surface input and the vehicle body swings little above _S in either the case the vehicle is traveling, by rotating the body 44 from the current position P _P in the counterclockwise direction abutment Each butting protrusion 4
An initializing process for calibrating the control origin is performed by returning to the origin after being brought into contact with 5a and 45b.

The storage device 55d stores the arithmetic processing device 5
A program necessary for the arithmetic processing of 5c is stored in advance, and a value and an arithmetic result required in the arithmetic processing are sequentially stored. Next, the operation of the above embodiment will be described with reference to FIGS. 11 to 14 showing an example of a multitask processing procedure in the arithmetic processing unit 55c of the microcomputer 55.

That is, the process of FIG. 11 is a start judging process for judging an initialization start condition. When the ignition switch (not shown) is turned on, a timer interrupt for every predetermined time (for example, 50 msec) is performed. First, in step S1, it is determined whether or not the initialization completion flag END is set to "1". When this flag is set to "1", it is determined that the initialization processing has been completed. Then, the timer interrupt process is terminated as it is, and the process proceeds to another task process. When the initialization completion flag end is reset to "0", the process proceeds to step S2.

In step S2, each step motor 41i (i = F) is stored in the control position storage area at the end of the previous control.
It is determined whether or not the final control position P _{Pi of (} L, FR, RL, RR) is stored. This determination is for determining whether or not the current position of each step motor 41i can be secured and control accuracy can be maintained at the start of control based on the ON state of the ignition switch.
_{When PFL to} P _PRR are stored, it is determined that the control accuracy can be maintained, and the process proceeds to step S3.

In step S3, the vehicle speed detection value V of the vehicle speed sensor 52 is set so that the noise or vibration generated in the initialization process due to the preset road noise is lost and the occupant cannot sense the vehicle speed. Set vehicle speed V _S higher than V ₁ (for example, 35k
m / h) to determine a whether or, V <V when is _S, the noise of the initialization process is determined to have a possibility to be sensed to the occupant goes to step S4, the counter CNT "0 ”, The timer interrupt process is terminated, and the process proceeds to another task process. If V ≧ V _S , the process proceeds to step S5.

In this step S5, it is determined whether or not the initialization permission flag INT is set to "1". When the initialization permission flag INT is reset to "0", it is determined that the initialization processing is not permitted. And the process moves to step S6. In step S6, the vertical acceleration vertical in the sensor 51i acceleration detected value X _2i "the absolute value road vibration input and the vehicle body moves up and down the preset is less set the vertical acceleration X _20"
It is determined whether it is less than. This determination is performed to determine whether or not the fluid force passing through the orifice due to the influence of the piston speed of the shock absorber at the time of performing the initialization process can perform the accurate initialization process without affecting the driving force of the step motor 41i. When | X _2i ″ | ≧ X ₂₀ ″, it is determined that accurate initialization processing cannot be executed, and the process proceeds to step S 4. When | X _2i ″ | <X ₂₀ ″ holds, It is determined that a proper initialization process can be executed, and the process proceeds to step S7.

[0033] In the step S7, the counter CNT "1" transition from incremented by the step S8, the count value of the counter CNT is equal to or a set value CNT ₀ or a preset, CNT < CNT ₀
, The timer interrupt process is terminated and the process proceeds to another task process. If CNT ≧ CNT ₀ , the process proceeds to step S9 and the initialization permission flag I
NT is set to "1", and then the process proceeds to step S10, where the counter CNT is cleared to "0", the timer interrupt process ends, and the process proceeds to another task process.

On the other hand, when the final control position P _Pi is not stored in the process of step S2 and when the result of the determination in step S5 is that the initialization permission flag INT is set to "1", the process proceeds to step S11. . In this step S11, the A / D converter 56
, The current power supply voltage E _N of the battery 53 is read, and then the process proceeds to step S12 to read the read power supply voltage E _N
Is determined to be equal to or higher than the initialization start voltage E _INT that can compensate for the drive torque of the step motor 41i set in advance, and when E <E _INT , the power supply voltage is too low to secure the reliability of the initialization processing. If it is determined that the processing cannot be performed, the timer interrupt processing is terminated without starting the initialization processing and the processing proceeds to another task processing. When E _N ≧ E _INT, it is determined that the reliability of the initialization processing can be secured. Then, the process proceeds to step S13 to clear the count value N of the monitoring counter in the power supply voltage monitoring process described later to “0”, and then proceeds to step S14 to start the initialization execution process shown in FIG. The interrupt processing ends.

In the initialization execution process, the priority is set higher with respect to other task processes, and as shown in FIG. 12, the process first proceeds to step S21 to execute the initialization process. This initialization process is performed by rotating the step motors 41FL to 41RR counterclockwise assuming that the final position P (the position immediately before the initialization process is executed) P of the valve element 31 is at the position shown in FIG. And outputs a step amount S gradually decreasing as a control signal at predetermined time intervals.
1 Accordingly, the abutment body 44 rotates in the counterclockwise direction while gradually reducing its rotation angle, and eventually rotates to the maximum pressure side position (−P _MAX ), so that the abutment body 44 It comes into contact with the abutting projections 45a and 45b, and stops rotating any more. From this state, the stepping motor 41
By outputting a predetermined step amount S _a relative FL～41RR, step motor 41FL~41RR the rotation angle a only position the position P of the body 44 i.e. the valve element 31 butting is rotated clockwise value "0 And the initialization completion flag END is set to "1" in this state.

Then, the process shifts to step S22 to determine whether or not the initialization completion flag END is set to "1". Initialization completion flag END
Is reset to "0" in step S23.
And the initialization stop flag STP is set to "1".
It is determined whether or not the initialization stop flag STP has been reset to "0". If the initialization stop flag STP has been reset to "0", the process proceeds to step S24, waits for a predetermined time, returns to step S21, and returns to the initialization stop flag S
If TP is set to "1", step S
Then, the process goes to step S25, where the initialization stop flag STP is reset to "0". Then, the initialization execution process is terminated, and the process goes to another task process.

If the result of the determination in step S22 is that the initialization completion flag END is set to "1", it is determined that the initialization processing has been completed, and the initialization execution processing is terminated as it is, and other task processing is completed. Move to In the present embodiment, when the step motors 41FL to 41RR are rotated counterclockwise and stepwise by a predetermined rotation angle, a predetermined time is maintained for each rotation position, and the supply voltage is maintained during the predetermined time. The driving force is set to “0” in the off state. That is, during the initialization, the driving force of the step motors 41FL to 41RR is interrupted. Further, as shown in FIG. 15, for example, an angle from the end position P to the extension side maximum position P _MAX and gamma, the speculative maximum overshoot position P _N to the compression side maximum position (-P _MAX) which is reached by and initialization processing Is set to be larger than the angle γ so that the final position P always reaches the maximum pressure side position (−P _MAX ) regardless of where the final position P is in the damping force control range. I have.

When the initialization execution processing of FIG. 12 is started, the initialization execution processing is simultaneously performed at predetermined time intervals (for example, 3.33 msec) in FIG.
The battery voltage monitoring process shown in FIG. 3 is executed as a timer interrupt process. In this battery voltage monitoring process, first,
In step S31, the power supply voltage E _N of the battery 53 is read, and then the process proceeds to step S32, where the power supply voltage E _N
Is the above-mentioned initialization start voltage E _INT
It is determined whether or not a monitor voltage E _WAT (<E _INT ) that can generate a minimum drive torque with a lower step motor 41i is exceeded. If E _N ≦ E _WAT , the process _proceeds to step S33. After the count value N of the monitoring counter is incremented by "1", the process _proceeds to step S34, and if E _N > E _WAT , the process directly _proceeds to step S34.
Move to 34.

In step S34, it is determined whether or not the count value N of the monitoring counter has reached a predetermined value N _S for determining that there is a possibility that the reliability of the initialization process may be reduced. If N _S , the process proceeds to step S35 to clear the initialization stop flag STP indicating stop of initialization to “0”, ends the timer interrupt process, and returns to the initialization execution process of FIG. _{If S} , step motor 4
It is determined that the reliability of the initialization has decreased due to the decrease in the driving torque of 1i, and the process shifts to step S36 to set the initialization stop flag STP to “1” and thereafter terminates the processing.

In the microcomputer 55,
12 and FIG. 13 are not executed
Sometimes, the damping force control process shown in FIG.
Execute as timer interrupt processing. This damping force control process
As shown in FIG. 14, first, in step S41,
Vertical acceleration detection value X_2i”(I = FL, FR, RL, RR)
Then, the process proceeds to step S42 and proceeds to step S41.
At each damping force variable shock absorber 3i position
Vertical acceleration X_2iLow-pass filter for ″
The vehicle vertical speed X is integrated by performing the processing._2i′
Out, and then proceeds to step S43 to calculate the calculated vehicle body.
Vertical speed X_2i'Is positive including zero.
This judgment is made by the piston of the variable damping force shock absorber 3i.
When the ton rod 35 moves to the extension side or
X_2iWhen '≧ 0
Is determined to be moving to the extension side, and step S4
4 and the vehicle body vertical speed X_2i′ To the preset expansion
True maximum value P of side position_TLMAXOn the body when
Lower speed X_2TM'Divided by X_2i'/ X_2TM'Exceeds 1
To determine whether or not X_2i'/ X_2TM'> 1
Then, the process proceeds to step S45, where X_2i'/ X _2TM′
= 1, the process proceeds to step S46, and X_2i'/
X_2TMIf '≦ 1, step S46 is performed as it is.
Move to

In step S46, the vehicle vertical speed X_2i′
And X_2TM'And the maximum position P on the extension side_TMAXAnd based on
The following formula (2) is used to calculate the target extension side position P._TTo
After the calculation, the process moves to step S47. P_T= (X_2i'/ X_2TM') P_TMAX (2) In this step S47, the data stored in the storage device 55d is stored.
Current position P _PAnd target position P_T(Or later
P to describe_C) And calculate this as the step control amount.
Update and store in a predetermined storage area of the storage device 55d as S
With the target position P_TOr P_CThe current position
P_PIs updated and stored, and then to step S48
The data is transferred to a predetermined storage area of the storage device 55d
Step control amount S is output to the motor drive circuit 59i.
Then, the process proceeds to step S49, where predetermined control ends.
Judge whether the condition is satisfied or not and satisfy the control end condition.
If not, end the timer interrupt processing and
Return to the main program and satisfy the control end condition.
Sometimes, the process proceeds to step S50 and the current position P
_PTo the ignition switch installed in the storage device 55d.
Backup power is supplied even if the switch is turned off.
Semiconductor memory or backup power
Electrically rewritable non-volatile memory that does not require a source
(E^TwoStored in the holding memory 55e composed of PROM)
After that, the process ends.

Here, the predetermined control termination condition is set, for example, when a self-holding period of a predetermined time has elapsed since the ignition switch was turned off. On the other hand, if the result of the determination in step S43 is X _2i ′ <0, it is determined that the piston rod 35 of the variable damping force shock absorber 3i is moving to the compression side, and the flow shifts to step S51 to shift the vehicle body vertical speed X _{2i Is} divided by the vehicle body vertical speed X _2CM 'when the true maximum value P _CMAX of the preset pressure side position is _obtained, and it is determined whether or not X _2i ' / X _2CM 'exceeds 1. _2i '/ _X2CM '> 1
, The process proceeds to step S52, where X _2i ′ /
After setting X _2CM ′ = 1, the _{process proceeds} to step S53,
When X _2i '/ X _2CM' is ≦ 1, the process moves to step S53.

In step S53, the vehicle body vertical speed X _2i '
And performing the following calculation formula (3) proceeds from the calculated target compression side position P _C to the step S47 on the basis of the on and the compression side maximum position P _CMAX X _2CM '. P _C = (X _2i ′ / X _2CM ′) P _CMAX (3) In the processing of FIGS. 11 to 14, FIG. 11 and FIG.
The process 2 corresponds to the initialization executing unit, the process in FIG. 13 corresponds to the initialization canceling unit, and the process in FIG. 14 corresponds to the control unit.

Therefore, when the ignition switch is turned on, the controller 4 is turned on, thereby turning on the microcomputer 55.
After the flags are reset to "0" by the arithmetic processing unit 55c and predetermined initialization processing such as clearing the count values N and CNT to "0" is executed, the processing in FIG. 11 is started.

At this time, since the initialization completion flag END has been reset to "0" by the initialization,
Final control position P _{PFL to} P _PRR at the end of previous control
It is determined whether or not is stored in the holding memory 55e (step S2). In the normal state, the last control positions P _{PFL to} P _PRR are stored in the holding memory 55e by the damping force control process of step S14 when the previous control ends. since it is, it is determined whether the vehicle speed V is set vehicle speed V _S or higher (step S3), and because the vehicle is stopped, the count value CNT of the time counter "0" timer interrupt processing is cleared to To end. Therefore, the initialization execution process of FIG. 12 is not started, and the damping force control process of FIG. 14 is executed instead.

In this stopped state, the occupant getting on and off and the load
If there is no loading / unloading, the body will swing
Output from vertical acceleration sensors 51FL-51RR
Vertical acceleration detection value X_2FL"~ X_2RR″ Is almost zero
And the vehicle vertical speed X_2FL'~ X_2RR′ Is also omitted
Since it is zero, the process goes from step S43 to step S44.
To step S46, and the extension target position P_TAlso
Body vertical speed X_2iIs zero because ′ is zero, and the step
The motor 41FL-41RR is the extension target position P _TMatches
Driven to Therefore, the damping force variable shock
The valve elements 31 of the absorbers 3FL to 3RR are positioned as shown in FIG.
The piston B is set to
The pressure side damping force is set to the soft state with the minimum state.

When the vehicle is started slowly from this stopped state and runs straight on a flat good road, the vehicle body hardly moves up and down again in this case.
Vertical acceleration detection value X _2FL ″ output from 1RR
X _2RR ″ becomes substantially zero, and the valve element 31 of the variable damping force shock absorbers 3FL to 3RR maintains the position B shown in FIG. 6, whereby the soft state in which the extension side and compression side damping forces of the piston 8 are in the minimum state. Therefore, even if vibrations due to fine irregularities on the road surface are input to the wheels, the vibrations are absorbed by the variable damping force shock absorbers 3FL to 3RR and are not transmitted to the vehicle body, so that a good ride comfort can be secured. .

In this good road running state, for example, when the vehicle passes through a transient step such as a step rising forward, and the vehicle does not move up and down due to the passage of the step, the vehicle vertical speed X
_{Since 2FL} 'to _X2RR ' are maintained at zero, to maintain the minimum damping force state, it is possible to absorb the thrust force when the wheel rides on the step, but ride on a relatively large step, If you can't absorb that thrust,
Body also would be displaced upward, thus resulting in the vehicle body vertical velocity X _2FL '~X _2RR' is increased in the positive direction. As described above, when the vehicle body vertical speeds X _2FL ′ to X _2RR ′ increase in the positive direction, the _{process proceeds to} step S44 through step S44.
6 goes to, so the extension side position P _T of the target maximum position P _TMAX side of the extension side position P _T1 in FIG. 8 is calculated, the valve body 31 of the damping force variable shock absorber 3FL~3RR shown in FIG. 5 The switching is controlled as follows. As a result, when the displacement speed X _1i ′ on the wheel side is higher than the displacement speed X _2i ′ on the vehicle body side due to the stepping over and the piston 8 moves to the compression side, the compression-side minimum damping force is maintained.
The vibration input to the wheel side can be absorbed, and when the climbing speed on the wheel side becomes lower than the climbing speed on the vehicle body side by overcoming the step from this state, the piston 8 moves to the extension side. At this time, since the damping force has a large value, the damping force exerts a damping effect of suppressing the rise of the vehicle body, and when the vehicle body stops rising thereafter, the vehicle body vertical speed _X2FL'- X
_{When 2RR} 'becomes zero, the step motors 41FL to 41RR are rotated counterclockwise and returned to the position B as described above, whereby both the compression side and the extension side are controlled to the minimum damping force, and then the vehicle body is When you start descending,
By the vehicle body vertical velocity X _2FL '~X _2RR' is increased in the negative direction in response to this, step S from step S43
51 and proceeds to step S53 through, by calculating the compression side target position P _C, the valve element 31 is rotated to further counterclockwise, is rotated in the rotated position shown in FIG. Therefore, when the vehicle body is lowered and the piston 8 moves to the pressure side, the damping force is increased, so that a large damping effect is exhibited.

Conversely, when the wheels pass through the step of descending forward, the relative speeds X _DFL ′ to X _DRR ′ increase in the forward direction due to the rebound of the wheels, but the vehicle body does not move up and down at this time. Body vertical speed X _2FL '~ X
_{Since 2RR} 'is zero, the damping coefficients of the damping force variable shock absorbers 3FL to 3RR maintain the minimum damping force, allow the wheels to descend, and then the vehicle body starts to descend, and the vehicle vertical speed _X2FL ' When to X _2RR 'is increased in the negative direction, and the compression side target position P _C becomes a large value, since the valve body 31 is rotated to the position shown in FIG. 7, a large damping force against the movement of the compression side of the piston 8 To exert a large vibration damping effect, and thereafter, the vehicle vertical speed X _{2F L} ′ to X _2RR ′
Depending on the compression side target position P _C is smaller becomes small, the valve body 31 is returned to position B side is rotated clockwise, the vehicle body vertical velocity X _2FL '~X _{2R R'} is zero, the valve The body 31 becomes the position B and returns to the minimum damping force state. Then, when you start to rise by the vehicle body unwag, since the vehicle body vertical velocity X _2FL '~X _2RR' is increased in the positive direction increases the extension phase target position P _T, the valve element 31 is rotated clockwise As a result, a large damping force can be applied to the movement of the piston 8 on the extension side to exert the vibration damping effect.

As described above, when the vehicle travels on a temporary step while traveling on a good road, a good vibration damping effect can be exerted by the skyhook control. also, by a positive vehicle body vertical velocity X _2FL '~X _2RR' (or negative) by Shin-side target position P _T (or pressure side target position P _C) is calculated, the piston 8 body rises Gasing The damping force is controlled to the minimum damping force in the vibration direction in which the piston 8 moves to the compression side, and the piston 8 moves to the compression side when the body moves up and the piston 8 moves to the extension side. When it is in the vibration direction, the damping force is controlled to the optimum damping force according to the vertical speed X _2FL ′ to X _2RR ′,
Good ride comfort can be ensured.

Even when the vehicle is traveling on a rough road, as in the case of passing through the step, the vehicle body rises and the piston 8 moves to the extension side, and the vehicle body descends and the piston moves to the compression side. The damping force is controlled to the minimum damping force in the vibration direction. Conversely, vibration suppression is performed when the vehicle body rises and the piston 8 moves to the compression side, and when the vehicle body descends and the piston moves to the extension side. When the damping force is in the vertical direction X
Control is made to an optimum value according to _2FL 'to _X2RR ', and a good ride comfort can be secured.

Thereafter, the vehicle speed V becomes equal to the set vehicle speed V._SReach
When the processing in FIG. 11 is executed, step S5 is performed.
Then, the process proceeds to step S6, where the vehicle is traveling on a flat good road.
The absolute value of the vertical acceleration detection value of the vertical acceleration sensor 51i.
Value | X_2i″ | Is the set acceleration X₂₀Is less than ″
Proceed to step S7 to set the counter CNT to "1" only.
This is incremented, and this is repeated
Value CNT is set value CNT ₀When you reach
Is set to "1" and the
The counter CNT is cleared to "0".

Therefore, when the processing of FIG. 11 is executed next, the processing shifts from step S5 to step S11,
It reads the power supply voltage E _N of the battery 53, and then proceeds to step S12, the process proceeds to step S13 initialization execution process of FIG. 12 is started when the power supply voltage E _N is initialized starting voltage E _INT above. When the initialization execution processing is started, the priority of this processing is high, so that the damping force control processing in FIG. 14 is suspended, and the initialization execution processing is executed with priority.

By this initialization execution processing, the stepping motor 41i is rotated counterclockwise so as to reduce the amount of rotation stepwise as shown in FIG. 45a, 45
b to abut and then is rotated clockwise by a predetermined amount a, in this state, will be set to "0" the current control position P _P.

In this state, the vehicle is running at the set vehicle speed V _S or higher, and the noise generated by the initialization processing and the noise due to the vibration are eliminated by the road noise, and the occupant does not feel uncomfortable. Absent. When the initialization execution process is started, the process shown in FIG.
The power supply voltage monitoring process 3 is also executed simultaneously as a timer interrupt process for the initialization process.

Therefore, the power supply voltage E _{N of the} battery 53
12 is higher than the monitor start voltage E _{WAT, not} to mention that it is higher than the initialization start voltage E _INT , it is determined that the initialization process can be performed normally, and the initialization execution process of FIG. 12 is continued. When the initialization process is completed and the initialization completion flag END is set to "1", the initialization execution process is terminated, and the process returns to the damping force control process.

By the way, for the duration of the initialization execution process of FIG. 12, as shown in FIG. 16, when the power supply voltage E _N is state occurs below the monitoring voltage E _WAT, the power supply voltage monitoring process of Figure 13 is executed Each time, the count value N of the monitoring counter is incremented by “1”. Until the count value N reaches the set value N _S , as shown in FIG. 15, the number of steps for contacting the abutting body 44 with the abutting projections 45 a and 45 b of the stopper plate 45 is set to the actual maximum number of steps. By setting a larger value, accurate control origin calibration can be performed, so that the initialization execution processing of FIG. 12 is continued. If the initialization processing is completed during this time, the initialization completion flag END is set. Is set to “1”, and the initialization execution processing ends.

[0058] However, the power supply voltage E _N monitoring voltage E _WAT
In this state, when the count value N of the monitoring counter becomes equal to or more than the set value N _{S, the} abutment body 44 is moved by the abutment member 44 of the stopper plate 45 due to insufficient driving torque of the step motors 41FL to 41RR. 45a, 4
5b, it is determined that the reliability of the initialization is degraded, and the initialization stop flag STP is set to "1" (step S3).
6).

Therefore, when the processing in FIG. 12 is restarted, the process proceeds from step S23 to step S25, resets the initialization stop flag STP to "0", and prepares to start the initialization execution processing again. To cancel the initialization execution process. Thereafter, in the processing of FIG. 11, when the initialization start condition is satisfied, the initialization execution processing is started again, and when the initialization processing is completed, the initialization completion flag END is set to “1”.
When the processing in FIG. 11 is executed, the timer interrupt processing is terminated as it is from step S1, and this state is maintained until the ignition switch is turned off and the control is terminated. Repeated.

Thereafter, the vehicle is stopped from the running state,
When the ignition switch off, when the processing of FIG. 13 has been executed, the process proceeds from step S49 to step S50, terminating the control is held by the holding memory 55e the current control position P _P as control position data I do. On the other hand, when the when the ignition switch turned on, the control position data P _P to the holding memory 55e represents the current position is not stored,
When the current control position of the variable damping force shock absorber 3i is indefinite, and the damping force control is executed through traveling, accurate damping force control can be performed until the initialization process at the set vehicle speed is executed. Disappears. Therefore, when the process of FIG. 11 is executed, the process proceeds from step S2 to step S11, and the power supply voltage E _N
Immediately starts when the voltage becomes equal to or higher than the initialization start voltage E _INT , and the initialization processing is executed at the time of startup.

As described above, according to the above-described embodiment, when the ignition switch is turned on, it is determined whether or not the current control position data _PP is stored. immediately initialization process is executed, when the control position data P _P is stored, the occupant predetermined initialization start condition which does not give discomfort initialization process is executed after the established, during the execution of this initialization process,
The power supply voltage is momentarily changed to the monitoring voltage E _WAT
Even if the following cases occur, when the count value N of the monitoring counter, which is counted up when the voltage becomes equal to or lower than the monitoring voltage, is less than the set value, the initialization process is continued, and if the initialization process is completed during this time, It can be determined that the initialization has been completed, and the initialization process is stopped only when the count value N becomes equal to or greater than the set value N _S. It is possible to reliably avoid a chattering phenomenon in which the initialization process is repeatedly stopped and restarted due to a large drop in the power supply voltage.

In the above embodiment, the case where variable damping force shock absorbers 3FL to 3RR are applied as actuators has been described. However, the present invention is not limited to this. The present invention can be applied to a stabilizer, an air suspension capable of changing a spring constant, and the like, when an open-loop controlled step motor is used.

Further, in the above embodiment, the case where the valve element 31 for controlling the damping force is formed in a rotary type is described. However, the present invention is not limited to this. Different flow paths may be formed on the side and in this case, in this case, step motors 41FL to 4FL
A pinion may be connected to the rotation shaft 41a of the 1RR, and a rack that meshes with the pinion may be attached to the connection rod 42 or an electromagnetic solenoid may be used to control the sliding position of the valve element 31.

Further, in the above embodiment, the case where the abutting body 44 is provided on the connecting rod 42 connected to the rotating shaft 41a of the step motors 41FL to 41RR and the stopper plate 45 is provided on the upper half body 12 has been described. The stopper plate 45 is connected to the connecting rod 42 in the reverse relationship,
4 may be provided on the upper half body 12. Further, instead of the stopper plate 45, a position detecting means such as a microswitch which engages with the abutting body 44 is provided. The drive of the step motors 41FL to 41RR may be stopped when the signal 44 is detected, and the origin calibration may be performed more accurately. In this case, since the occurrence of vibration and noise due to the contact between the abutment body and the stopper plate is small, the initialization process can be executed when the ignition switch is turned on by omitting the holding memory 55e. Further, even when the occurrence of vibration and noise can be ignored, the initialization process can be executed when the ignition switch is turned on.

Further, in the above embodiment, the case where the count value N of the monitor counter is incremented when the power supply voltage becomes equal to or lower than the monitor voltage has been described. However, the present invention is not limited to this. When the count value becomes equal to or less than the preset value, the count value of the monitoring counter is preset to the set value N _S , and then decremented sequentially. When the count value N becomes zero, the initialization stop flag ST
P may be set to “1”.

Furthermore, in the above embodiment, the case where the skyhook approximation control in which the vertical acceleration of the vehicle body is detected and the damping force is controlled based on the vertical acceleration is described, is limited to this. Instead, a stroke sensor for detecting the relative displacement between the vehicle body and the wheels is separately provided, and the relative speed X _Di 'obtained by differentiating the relative displacement detection value X _Di of the stroke sensor and the vehicle body vertical speed X _2i ' described above. Based on this, the following equation (3) is calculated to calculate a damping coefficient C, and based on the damping coefficient C, a target position is calculated with reference to, for example, a map corresponding to FIG. It may be performed.

C = C _{S ×} X _2i ′ / X _Di ′ (3) where C _S is a preset damper damping coefficient.
Further, in the above-described embodiment, the case has been described in which the posture change of the vehicle body due to vibration input from the road surface is suppressed.
However, the present invention is not limited to this, and control for suppressing a change in the attitude of the vehicle body by detecting a running state of the vehicle, such as a roll state or a braking state, may be performed.

Further, in the above-described embodiment, the case where the control origin is calibrated by the normal initialization process when the vehicle is traveling on a flat road surface at the set vehicle speed V _S or higher has been described. However, the present invention is not limited to this. If the piston speed of the damping force variable shock absorber 3i is high, the step amount due to the driving force of the step motor 41i fluctuates due to the influence of the fluid force passing through the orifice, and step-out may occur. Alternatively, the piston speed may be estimated, and the control origin may be calibrated by the initialization process after reaching the piston speed at which the step-out may occur.

Further, in the above embodiment, the case where the control is performed by applying the microcomputer 55 has been described. However, the present invention is not limited to this. The output of the vertical acceleration sensor 51i is integrated to reduce the vehicle vertical speed. An electronic circuit such as an integrator for calculating and an arithmetic circuit for calculating a target position may be combined. Furthermore, in the above embodiment, each wheel 1FL-1RR of the vehicle body 2
Although the case where the vertical acceleration sensors 51FL to 51RR are provided at the position has been described, one of the vertical acceleration sensors may be omitted and the vertical acceleration at the omitted position may be estimated from the values of the other vertical acceleration sensors. Good.

The variable damping force shock absorber is not limited to the above-described configuration, and the present invention is applied to other variable damping force shock absorbers in which the damping force can be switched in two or more steps by a stepping motor. obtain.

[0071]

As described above, according to the first aspect of the present invention, when the power supply voltage becomes equal to or higher than the set voltage, the initialization of the control system is started by the initialization execution means. Is lower than the monitor voltage lower than the set voltage, the decrease time is measured by the initialization suspending means, and when the sum of the decrease times is less than the preset value, the initialization is continued by the initialization execution means, and the decrease is continued. When the sum of the times becomes equal to or more than the set value, it is determined that the initialization is defective and the initialization of the initialization execution means is stopped. During this time, the initialization processing can be continued, and during this time, the initialization processing can be completed. Can, to prevent the chattering phenomenon to repeat initialization start and stop and the like in the conventional example described above, there is an advantage that it is possible to complete the early initialization process.

According to the second aspect of the present invention, the initialization is started when the vehicle speed is equal to or higher than the set vehicle speed and the detected power supply voltage is equal to or higher than the set voltage. It is possible to obtain an effect that it is possible to prevent a noise caused by the driving noise of the step motor or the noise caused by the engagement piece from coming into contact with the stopper and a noise caused by the vibration by a road noise or the like, thereby giving a passenger an uncomfortable feeling.

Further, according to the third aspect of the present invention, the initialization canceling means updates the count value of the counter when the detected power supply voltage becomes less than the monitor voltage, so that the power supply voltage becomes higher than the monitor voltage. When returning, the count value can be held, and the effect that the sum of the times when the voltage is equal to or lower than the monitoring voltage, that is, the accumulated time can be easily detected is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a basic configuration of the present invention.

FIG. 2 is a schematic configuration diagram showing one embodiment of the present invention.

FIG. 3 is a partially sectional front view showing an example of a variable damping force shock absorber.

FIG. 4 is an enlarged sectional view showing a damping force adjusting mechanism in a maximum damping force state when the vehicle body is lifted.

FIGS. 5A and 5B are enlarged cross-sectional views showing a damping force adjusting mechanism in an intermediate damping force state when the vehicle body is lifted, wherein FIG. 5A shows a hydraulic oil path on the extension side and FIG.

FIGS. 6A and 6B are enlarged cross-sectional views showing a damping force adjustment mechanism when the vehicle body does not fluctuate, wherein FIG. 6A shows a hydraulic oil path on the extension side and FIG.

FIGS. 7A and 7B are enlarged cross-sectional views showing a damping force adjusting mechanism in a state of maximum damping force when the vehicle body descends, wherein FIG. 7A shows a hydraulic oil path on the extension side and FIG.

FIG. 8 is an explanatory diagram showing a damping force characteristic with respect to a position of a valve body of a variable damping force shock absorber.

FIG. 9 is an enlarged sectional view taken on line AA of FIG. 3;

FIG. 10 is a block diagram illustrating an example of a controller.

FIG. 11 is a flowchart illustrating an example of an initialization start determination processing procedure of a controller.

FIG. 12 is a flowchart illustrating initialization execution processing of a controller.

FIG. 13 is a flowchart showing a power supply voltage monitoring process executed during the initialization execution process of FIG. 12;

FIG. 14 is a flowchart illustrating an example of a damping force control process of a controller.

15 is an explanatory diagram of the operation of the initialization (control origin calibration) process of FIG.

FIG. 16 is an explanatory diagram showing a relationship between a power supply voltage fluctuation at the time of initialization and a count value of a monitoring counter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1FL-1RR Wheel 2 Body 3FL-3RR Variable damping force variable shock absorber 4 Controller 8 Piston 11 Lower half 12 Upper half 13 Extension oil flow path 14 Compression oil flow path 31 Valve element 35 Piston rod T1-T3 Extension side flow path C1-C4 Pressure side flow path 41FL-41RR Step motor 51FL-51RR Vertical acceleration sensor 52 Vehicle speed sensor 53 Battery 55 Microcomputer 59FL-59RR Motor drive circuit

Continuation of front page (56) References JP-A-6-58359 (JP, A) JP-A-8-108729 (JP, A) JP-A-7-329532 (JP, A) JP-A-6-135215 (JP) JP-A-2-206399 (JP, A) JP-A-5-80815 (JP, U) JP-A-5-71007 (JP, U) JP-A-6-12971 (JP, Y2) (58) Field surveyed (Int.Cl. ⁷ , DB name) B60G 17/015 F16F 9/50 H02P 8/00 303

Claims (3)

(57) [Claims] 1. The suspension characteristics can be individually controlled by controlling the rotation of a valve body by a step motor interposed between a vehicle body-side member and a wheel-side member and driven according to an input control signal. And a control means for detecting a change in posture of the vehicle body and outputting the control signal corresponding to the detected change in posture to the step motor to perform open-loop control. Power supply voltage detection means for detecting a power supply voltage to be supplied, and initialization execution for performing initialization of the control means when a power supply voltage detection value of the power supply voltage detection means reaches a preset voltage for performing initialization of a control system. Means, and after the initialization is started by the initialization execution means, A suspension control device, comprising: initialization stop means for stopping the initialization of the initialization execution means when the sum of the times during which the monitoring voltage is equal to or less than the monitoring voltage lower than the set voltage is equal to or more than the set value. 2. The suspension control device according to claim 1, wherein said initialization executing means initializes the control means when the vehicle speed is equal to or higher than a set vehicle speed and a power supply voltage detection value is equal to or higher than the set voltage. . 3. The initialization canceling means includes a counter for updating a count value while the power supply voltage detection value is equal to or less than a monitor voltage, and the initialization is stopped when the count value of the counter reaches a set value. The suspension control device according to claim 1, wherein the suspension control device is configured as follows.