JPS6280108A - Suspension controlling device - Google Patents

Abstract

PURPOSE:To rapidly suppress the vibration of a car by varying a suspension characteristic when judged that car height data correspond to a varying condition, while restoring said suspension characteristic when judged that said data correspond to a restoring condition. CONSTITUTION:A judging means M2 judges whether car height data from a car height detecting means M1 which detects the interval between a body and a wheel as a car height, correspond to a varying condition or a restoring condition, and a suspension characteristic is varied or restored in accordance with the judged result. This judging means M2 has a variation judging means M4 which judges that the data correspond to the varying condition when the difference between the maximum value and the minimum value of the car height data within a predetermined variation judging time is above a defined variation judging value, and a restoration judging means M5 which judges that the data correspond to the restoring condition when a condition that the maximum value and the minimum value of the car height data within a predetermined restoration judging time is below a defined restoration judging value, has continued certain times.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a suspension control device, and more specifically, to a system that adjusts suspension characteristics in response to the condition of the road surface on which the vehicle is traveling. Regarding changeable suspension control devices,
.

[Conventional technology 1] The condition of the road surface on which the vehicle is traveling is detected by a vehicle height sensor that detects, for example, the displacement of the distance between the vehicle body and the axle, and when driving on a rough road, the vehicle height is changed according to the suspension characteristics of the vehicle. A suspension control device has been developed that suppresses vehicle body vibration and improves both ride comfort, maneuverability, and stability.For example, when 11 cars change from driving on a good road to driving on a rough road. ``Vehicle height adjustment device'' configured to raise the vehicle height by more than a predetermined value to prevent bottoming from occurring due to vehicle bouncing, etc.
No. 808) and the like have been proposed. In such conventional technology, when the actual vehicle height exceeds a predetermined determination level,
When this frequency exceeds a predetermined value, it is determined that the vehicle is traveling on a rough road, and control is performed to change the vehicle height to a vehicle height for traveling on a rough road that is higher than when traveling on a good road.

[Problems to be Solved by the Invention] The prior art 4P suspension system 11 has the following problems. In other words, (1)
Conventionally, continuous rough roads have been determined by counting, for example, the number of times the actual vehicle height has risen by a predetermined value or more from the average vehicle height within a predetermined period of time.

Therefore, in order to determine whether a road is continuously rough, it is necessary to cover the road surface for a predetermined period of time, and there is a problem in that it is difficult to determine whether the road is continuously rough in a short period of time. Therefore, considering the current road conditions, there is a possibility that the vehicle has already moved from the bad road to a good road by the time a bad road is detected, and the reliability of bad road detection is also at a low level. .

(2) Also, related to the problem (1) above, since rough road judgment is delayed, suspension characteristics etc. are changed for specific periodic imaging that accompanies driving on rough roads, such as so-called pitching, bouncing, etc. There is also the problem that it is not possible to promptly take measures such as suppressing these images. For this reason, the above-mentioned vibrations continue, causing problems such as not only the uncomfortable gaping for the occupants but also changes in the vehicle's attitude, resulting in a decrease in maneuverability and stability.

(3) Furthermore, once the suspension characteristics are changed,
The vibration state of the vehicle body changes even when driving on the same road surface, but in the conventional judgment of continuous rough roads, the judgment conditions are not corrected for the above-mentioned changes in the vibration state.
There is also the problem that the control to change the suspension characteristics causes hunting, and unnecessary changes to the suspension characteristics are performed in a complicated manner, resulting in a decrease in the durability and reliability of the actuator and the like.

An object of the present invention is to provide a suspension control device that reliably detects vibrations caused by continuous driving on rough roads and specific circumferential vibrations, such as pitching and bouncing, and suitably changes suspension characteristics. .

Means for Solving the Problems] The present invention adopts the configuration shown in FIG. 1 in order to solve the above problems. FIG. 1 is a diagram conceptually illustrating the content of the present invention and showing a horizontal configuration. As shown in FIG. 1, the present invention includes a vehicle height detection means M1 that detects the distance between the vehicle body and the wheels as the vehicle height, and whether vehicle height data obtained from the detected vehicle height corresponds to a change condition. or determining means M2 for determining whether the return condition is met; and when the determining means M2 determines that the vehicle height data falls under change condition f4, the 1J suspension characteristic is changed;
On the other hand, in a suspension control 2I+ device comprising: a suspension characteristic changing means M3 that returns the suspension characteristic to its original state when it is determined that the return condition is met, the determining means M2 changes the vehicle height data within a predetermined change determination time; If the difference between the maximum value and the minimum value is greater than or equal to a predetermined change judgment value, a change ¥111 means M4 determines that the change condition is met, and J3 is added within a predetermined return judgment time. A state in which the difference between the maximum value and the minimum value of the F vehicle allocation height data is less than or equal to the predetermined return judgment value is
The present invention provides a suspension control device characterized in that it is equipped with a return determination means M5 that determines that the return condition is met if the return condition is met a predetermined number of times consecutively.

The vehicle height detection means M1 detects the distance between the wheels and the vehicle body as the vehicle height. For example, the displacement of the suspension arm relative to the vehicle body may be detected by a potentiometer and output as an analog signal. Alternatively, for example, the displacement may be detected as a rotation angle of the grating disk and output as a digital signal. Note that vehicle height data is calculated by 1q from this vehicle height. Here, the ili height data includes various characteristics such as the amount of displacement from the target vehicle height, the displacement speed of the vehicle height, the displacement acceleration, and the amplitude of the vehicle height vibration. The amount of displacement from the target vehicle height is the difference between the preset target vehicle height and the current vehicle height, the vehicle height displacement speed is the change in vehicle height within a certain period of time, and the displacement acceleration is the difference between the vehicle height and the current vehicle height. It is a change in displacement speed within a certain period of time. Further, the amplitude of the vehicle height vibration is the difference between the maximum value of 1 ft and the minimum value of the vehicle height detected within a certain fixed period of time.

Resvenge: The property changing means M3 is a means for changing or returning the characteristics of the suspension to its original state.

For example, the spring constant of the suspension, the damping force of the shock absorber, the "push" characteristics, the stabilizer "characteristics, etc. may be changed in multiple stages or in a stepless manner.

That is, in an air suspension or the like, it is possible to change the spring constant by communicating or blocking the main air chamber and the auxiliary air chamber. Further, for example, the damping force can be increased or decreased by changing the diameter of the orifice through which the oil of the shock absorber flows. moreover,
For example, by changing the stiffness of the bushing or the stiffness of the stabilizer, +7゛spendicon characteristics e 1il
i A state (HARD) and G; in the intermediate (7) state rl!
? (T in SPot) or soft state (SOFT)
It is also possible to change to

The change determination means M4 means that the difference between the maximum 1n and the minimum b0 of vehicle height data obtained from the vehicle height detected by the vehicle allocation height detection means M1 within a predetermined change determination time is greater than or equal to the predetermined change se1 predetermined value. In this case, it is determined that the change condition is met. For example, the above vehicle height data is detected at every predetermined detection time, the difference between the maximum value and the minimum value of the above detection results is determined every predetermined change judgment time, and the resulting value is set in advance. It may be configured to determine whether or not the vehicle ^-f-y falls under the change condition at the predetermined change determination time by comparing the predetermined change determination value with the predetermined change determination value.

The return determination means M5 is configured to determine whether the difference between the maximum value and the minimum value of the vehicle height data obtained from the vehicle height detected by the vehicle height detection means M1 within a predetermined return determination time is equal to or less than a predetermined −return determination value. If a certain condition continues for a predetermined number of times, it is determined that the condition falls under the conditions for reinstatement. For example, the above vehicle height data is detected at every predetermined detection time, and the difference between the maximum value and the minimum value of the above detection result is calculated every predetermined return judgment time, and the height of the vehicle height is calculated in advance. Predetermined return judgment 1ifM
The comparison result at the predetermined return determination time is stored by comparing with 4! It can also be configured to determine whether the data satisfies the return conditions.

The determining means M2 is composed of the change determining means M4 and the return determining means M5, and determines whether the vehicle height data obtained from the vehicle height detected by the vehicle height detecting means M1 corresponds to the change condition or not. It is for determining whether the size corresponds to the return condition.The determination means M2, the change determination means M4, and the return determination means M5 can be realized, for example, as independent discrete logic circuits.Furthermore, for example, It is configured as a logic operation circuit equipped with a CPU, ROM, RAMJ>, and other peripheral circuit elements, and implements each of the above means according to a predetermined processing procedure, so that the vehicle height data satisfies either of the above two conditions. It can also be configured to determine whether or not it is applicable.

[Function] As shown in FIG. 1, the suspension controller υ11 device of the present invention has a
! ? The determining means M2 determines whether the vehicle height data corresponds to the change ordinance or the return conditions, and if the change conditions are met, the suspension is changed by the suspension characteristics changing means M3. The characteristics are changed, and if the return conditions are met, processing is performed to restore the suspension characteristics to their original state. In this case, the change determination means M4 determines that the change condition is met if the difference between the maximum value and the minimum value of the vehicle height data within the predetermined change time is equal to or greater than a predetermined change determination value; The return determination means M5 operates to determine that the return condition is satisfied if the difference between the maximum value and the minimum value of the vehicle height data within a predetermined return determination time is less than or equal to a predetermined return determination value for a predetermined number of consecutive times. .

Therefore, the suspension control device of the present invention reliably detects vibrations of the vehicle body during continuous driving on rough roads or vibrations of the vehicle body that have a specific cycle, and changes or restores the suspension characteristics so that the vibrations are suppressed. I will work to bring it back to normal. As described above, each component of the present invention functions to solve the technical problem of the present invention.

"Embodiment" Hereinafter, a preferred embodiment of the present invention will be described in detail based on the drawings.

FIG. 2 shows a suspension control device for an automobile using an air suspension, which is an embodiment of the present invention.

111R represents a right front wheel height sensor provided between the right front wheel and the vehicle body, and detects the distance between the right suspension arm that follows the movement of the wheel and the vehicle body. H
IL represents a left front wheel height sensor provided between the left front wheel and the vehicle body, and detects the distance between the left suspension arm and the vehicle body.

112C represents a rear wheel height sensor installed between the rear wheel and the vehicle body, and detects the distance between the rear suspension arm and the middle rest. Vehicle height sensor HIR.

1-11L, H2C short cylindrical main body IRa, 1La.

ICa is fixed to the vehicle body side, and the main body IRa, 11-a,
Links 1Rb, 11b in a direction approximately perpendicular to the central axis of iCa
, 1Cb are provided. The links 11b, 1Lb,
At the other end of ICb are turnbuckles IRc, 1Lc, 1C.
The turnbuckle 1Rc is rotatably attached to the turnbuckle 1Rc.

The other ends of 1Lc and 1Cc are rotatably attached to a part of each suspension arm.

J3, vehicle height sensor + jl'1 R, HI L, H2C's main body is equipped with multiple photo interrupters, and a disc plate with a slit coaxial with the center axis of the vehicle height sensor responds to changes in vehicle height. 41-internal signal.

31 L, SIR, S2L, S2R represent the lζ air suspension installed on the right-hand rear wheel, respectively.Jl,
The air suspension 82L is installed in parallel with a suspension spring (not shown) between the suspension arm of the left rear wheel and the vehicle body. The air suspension S2L includes a main air chamber 52La and a sub air chamber 821b that perform an air spring function, a shock absorber 82LC, and an actuator A that changes the air spring constant or shock absorber damping force.
It is composed of 2L. 5IL1SIR and 82R also represent air suspensions with similar configuration and functions,
Air suspension SIL is on the left front wheel, air suspension S1R is on the right front wheel, [Asus Penjicon S 2 R
are located on the right rear wheel.

10 is each air suspension SIL, S1R.

This represents a compressed air supply/discharge system for the air springs S2L and S2R, and a compressor 10b is operated by a motor 10a to generate compressed air. This compressed air is guided to the air dryer 10d via the check valve 10c. The check valve 10c is connected to the air dryer 10 from the conbrella v10b.
The direction toward d is defined as the forward direction. air dry l-1
06 is each air suspension 81 L, SI R, S2
The compressed air supplied to L and 82R is dried, and the air piping and each Niarisu Pension 81 L, 31 R, and S2L are dried.

In addition to protecting the S2R components from moisture, each Niaris Pension 31 L, SI R, 82 m.

Main air chambers 51La, 51Ra, 521-a of 82F<.

52Ra and auxiliary air chamber 81 Lb, 5IRb.

52Lb, 52Rb internal moisture phase change (pressure abnormality reported in H) is prevented.The check valve of the non-return valve 10e with fixed throttle is used for each air suspension SIL, SL such as compresses f 10 b f'X. The direction toward R, S2L, and S2R is defined as the forward direction.The fixed throttle check valve 10e
When compressed air is supplied, the check valve part listens, and when compressed air is discharged, the check valve part closes, and the air is discharged only from the fixed throttle part. The exhaust valve 10f is a 2-point, 2-position spring offset type solenoid valve. The exhaust valve 10f is normally in the position shown in FIG.
When discharging compressed air from S2L and 82R, the communication state is switched to the position shown on the right side of FIG. 2, and the compressed air is discharged into the atmosphere via the fixed throttle check valve 10e and the air dryer 10d.

11. , , V1R1V2L and V2R are air spring supply and exhaust valves that perform a vehicle height adjustment function, and are respectively arranged between each air suspension SIL, S1R, S2L, and S2R and the compressed air supply and exhaust system 1o described above. ing. The air spring supply and exhaust valves V11-1VIR, V2L, V2
R is a 2-port 1-24iI spring A-set 1-type solenoid valve, which is normally located at a position not shown in Figure 2 and is in the cutoff state, but when adjusting the vehicle height, It is switched to the communication state shown above. That is, when the air spring supply and exhaust valves V1 L, VI R, V2LXV2R are brought into communication, the main air chamber 51 of each air suspension
Air supply and exhaust becomes possible between La, 81 Ra, 52La1S2Ra and the compressed air supply/exhaust system 10, and if the air supply is shifted, the volume of the main air chambers 51LaXSIRa1S2La, 52Ra increases and the vehicle height becomes higher, and due to the weight of the vehicle. Exhaust 1
If so, the volume will be reduced and the vehicle height will be lowered. Further, when the air spring supply/exhaust pulses 7V1L, VlR, V2L, and V2R are cut off, the vehicle height is maintained at the vehicle height at that time.

In this way, the above-mentioned exhaust valve valve 10f of the compressed air supply and exhaust system and each of the above-mentioned air spring supply and exhaust valves V11-1V
By performing communication/cutoff til control of IR, V2L, and V2R, air suspension S1L, S1R, and
2L%S2F<(1) Main air chamber 5ILa, 51Ra, 5
It is possible to adjust the vehicle height by changing the volumes of 2La and 52Ra.

SE1 is a vehicle speed sensor installed inside the speedometer, and outputs a signal according to the vehicle speed.

The above vehicle height height IIL, Ll I R, H2Ct
Each signal from the vehicle speed sensor SEI and the vehicle speed sensor SEI is input to an electronic control unit (hereinafter referred to as ECU) 4. ECIJ4 converts these signals, processes the data, and uses air suspension actuators △11-1△1R, A 2 L, A to perform appropriate control as necessary.
2R, skyffiha*supplyiJlki/(/Iz7V IL,
VlR, V2L, V2R1 compressed air supply and exhaust system Noshi-9
A starting signal is output to the solenoid of the exhaust valve 10a and the exhaust valve 10f.

Next, based on Figures 3 and 4, air suspension SIL
, S1R, S2L, and S2R.

Since each air suspension has a similar configuration, the right-side air suspension suspension will be described in detail.

As shown in FIG. 3, this air suspension S2R includes a shock absorber 52Rc consisting of a conventionally well-known piston/cylinder, and a shock absorber 52Rc.
2Rc.

Cylinder 1 of shock absorber 52Rc (buffer)
A center shaft (not shown) is supported at the lower end of 2a,
The upper end of the piston rod 12b extending from a piston (not shown) slidably disposed in the cylinder 12a is provided with a cylindrical elastic flu s' for elastically supporting the piston rod 12b on the vehicle body 16. 18 are provided. In the illustrated example, the shock absorber 52Rc is a conventionally well-known variable damping force shock absorber whose damping force can be adjusted by operating a valve IN function provided on the piston, and adjusts the reduced force. A control rod 20 for this purpose is rotatably disposed within the piston rod 12b via a seal member 22 in a liquid-tight manner.

The air spring device 14 includes a peripheral wall member 26 comprising a bottom portion 26a provided with an opening 24 through which the screw rod 12b passes, and a peripheral wall portion 26b rising from the edge of the bottom portion.
, an upper housing member 28a disposed to cover the peripheral wall member 26 and fixed to the vehicle body, and the housing member 2
The chamber 32 includes a lower housing member 28b with an open lower end connected to the lower end of the lower housing member 8a, and a diaphragm 30 made of an elastic member that closes the lower end of the lower housing member 28b. The chamber 32 has an opening 34 corresponding to the opening 24 provided at the bottom 26a of the peripheral wall member, and is connected to a lower main air chamber 52Ra and an upper sub air chamber by a partition member 36 fixed to the bottom 26a. 52Rb, and rain air chambers 52Ra and 52Rb are filled with compressed air. The partition member 36 is provided with a conventionally well-known buffer rubber 40 that can come into contact with the upper end of the cylinder 12a.
0, both openings 24d3 and 34 between 0[I are connected to the main air chamber S
2R) A passage 42 for communicating with 1 is formed.

The cylindrical elastic assembly 18 is arranged around the piston rod 12b inside the circumferential wall member 26 that constitutes the inner circumferential wall of the sub air chamber 52Rb in the circumferential wall 26b. rain air chambers 52Ra and 52Rb
A valve device 44 is provided to control communication between the two.

The cylindrical assembly 18 includes an outer cylinder 18a, a cylindrical elastic body 18b, and an inner cylinder 18C, which are arranged concentrically with each other,
The cylindrical elastic member 18b is fixed to both cylinders 18a and 18c. The outer part [18a] of the cylindrical assembly 18 is press-fitted into the peripheral wall part 26b of the peripheral wall member 26 fixed to the vehicle body via the upper housing part U28a. Also,
A valve number body 448 of the valve device 44 that allows one passage of the piston rod 12b is fixed to the inner cylinder 18G, and since the piston rod 12b is fixed to the valve number body 44a, the screws and rods are fixed. 1.2b is elastically supported by the vehicle body via the cylindrical elastic assembly 18.

The space between the outer cylinder 18a and the peripheral wall portion 26b is sealed by an annular air seal member 46, and the piston rod 12b
An annular air seal member 4 is provided between the valve number container 44a and the valve number container 44a.
It is sealed by 8. Further, the space between the inner cylinder 18c and the valve number body 44a is sealed by an annular air seal portion 050.

A hole 52 that extends parallel to the piston rod 12b and is open at both ends is formed in the valve number body 44a, and a rotary valve body 44b is rotatably housed in the hole.

The rotary valve body 44b includes a main body portion 56a that can come into contact with a lower positioning ring 54a disposed at the lower end of the hole 52, and a small diameter body portion 56a that projects from the main body portion toward one of the cylindrical elastic assemblies 18. An operation section 56b is provided. An upper positioning ring 54b is disposed at the upper end of the hole 52, and cooperates with the lower positioning ring 54a to prevent the rotary valve body 44b from falling out of the hole 52. There is a hole 5 between the main body part.
An annular seal base 60 is disposed on the right side of the inner air seal portion U38a and the outer air seal member 581) for sealing the inner air seal portion U38a and the outer air seal member 581). Also, between the seal base 60 and the main body portion 56a of the rotary valve (A44b), when the main body portion 56a of the valve body indicated by i'+7J is pressed against the seal base 60 by air pressure, the rotary movement of the rotary valve body 44b is controlled. A friction reducing portion vU62 is provided for smoothing.

Below the cylindrical elastic assembly 18, there is a
．． 34 and the main air chamber 5 through the passage 42 of the buffer rubber 40.
2Ra is formed in the main body portion 55a of the rotary valve body 44b.
A recess 66 is formed that is open to the P member 64. Further, a communication passage 68 is formed in the main body portion 56a, passing through the main body portion in the diametrical direction and crossing the recess 66.

The valve number container 56b that receives the valve body 56a has a fourth valve number container 56b.
As clearly shown in the figure, a pair of ventilation passages 7O are provided, one end of which can communicate with the communication passage 68, respectively.
The ventilation passages extend outward in the diametrical direction of the hole 52 on substantially the same plane toward the outer periphery of the valve body 44b, and the other end of each ventilation passage 70 is open to the outer peripheral surface of the holding body 44a through a seat hole 72. do.

Further, between the pair of ventilation passages 70 in the circumferential direction of the hole 52, a ventilation passage 74 whose one end can be communicated with the communication passage 68 is arranged so that the ventilation passage 74 is located on substantially the same plane as the ventilation passage 70 toward the outer periphery of the holding body 44a. Stretch. The diameter of the ventilation passage 74 is smaller than that of the ventilation passage 70, and the other end of the ventilation passage 74 has a seat hole 75.
It opens onto the outer circumferential surface of the push container 44a. On the inner peripheral surface of the inner cylinder 18c that covers the outer periphery of the holding container 44a,
An annular groove 76 surrounding the outer peripheral surface of the holding body 448 is formed to communicate the seat holes 72, 75 of the ventilation passages 70 and 74.

The inner cylinder 18G is formed with an open lower part 8 that opens into the groove 76 forming an annular air passage, and the cylindrical elastic member 18b has an elastic member corresponding to the open lower part 8. A through hole IL80 is formed that extends radially outward.

Further, each through hole 80 is an opening 82 provided in the outer cylinder 18a.
It opens onto the outer circumferential surface of the outer cylinder 18a. Accordingly, the open lower portion 8° 82 and the through hole 80 define four air passages that are provided corresponding to the air passage 70 and that pass through the cylindrical elastic assembly 18.

The lower part 8.82 and the through hole 80 are connected to the sub air chamber 5.
2Rb, the auxiliary air chamber 82r!
A plurality of openings 84 that open to b are provided at equal intervals in the circumferential direction. All openings 84 and the opening lower 8.82
In order to communicate with the through hole 80, an annular groove 86 is formed on the outer circumferential surface of the outer cylinder 18a and surrounds the outer cylinder at the part where the frontage 82 opens, forming an annular air passage. The opening 84 opens into the groove 86 .

In the example shown in FIG. 4, the open lower lower part 8.82 and the through hole 80 are provided corresponding to the two ventilation passages 70 of the holding body 44a, but between the inner cylinder 18c and the holding body 44a. Since the annular air passage 76 is formed in which the air passages 70 and 74 communicate with each other, the elastic member 18
The air passage can be formed at a desired position in the circumferential direction of b.

Referring again to FIG. 3, the upper end of the piston rod 12b is used to adjust the hole reducing force of the vacuum absorber 52Rc. f
'! A conventionally well-known actuator A2R is provided for rotationally operating the control rod 20 and the rotary valve body 44b of the valve device 44. is rotated.

This Air Suspension S2R is configured as described above, and has the following effects.

First, the rotary valve body 44b is held in the closed position as shown in FIG. 4, but in a position where the communication passage 68 of the valve body does not communicate with any of the ventilation passages 70 and 74 of the holding body 44a. When this happens, the communication between the sub air chamber 52Rb and the main air chamber 52Ra is cut off, so that the spring constant of the suspension S2R is set to a large value.

Also, the communication path 6 of the valve body is controlled by the actuator △2R.
8 communicates with the large-diameter ventilation passage 70 of the holding body 44a. , the spring constant of the suspension S2R is set to a small value because it communicates with the sub air chamber 52Rb through the open lower 8, q through hole 80, and openings 82 and 84 of the elastic assembly 18.

Moreover, when the communication passage 68 of the rotary valve body 44b is operated to a position communicating with the small diameter ventilation passage 74 of the holding body 44a by adjusting the actuator A2R, the main air chamber 5
2Ra is the communication passage 6 communicating with the main air chamber 52Ra.
8. Small diameter ventilation passage 74, said air passage 76, said open lower part 8 of said elastic assembly 18, through hole 80 OJ: Tj D
il D 8213 and opening 1] 84, 'auxiliary air v
Connects to S2Rb. Since the small-diameter air passage 74 provides greater air resistance than the large-diameter air passage 70,
The spring constant of the suspension S2R is set to an intermediate value.

Next, the configuration of the ECLI 4 will be explained based on FIG.

The ECIJ 4 inputs and calculates data output from each sensor according to a control program, and also includes a central processing unit (hereinafter referred to as CPU) 4a that performs processing to output control signals to each ladder device, and a central processing unit (hereinafter referred to as CPU) 4a, which performs the above-mentioned control. Read-only memory (hereinafter referred to as ROM) in which programs and initial data are stored 4b, E
Random access memory (hereinafter referred to as RAM) in which data input to the CU 4 and data necessary for performance control are read. 401 Even if the key switch of the car is turned off, it retains the data necessary afterward. It is configured as a logic operation circuit centered around a backup random access memory (hereinafter referred to as backup RAM) 4d backed up by a battery, an input port (not shown), a waveform shaping circuit provided as necessary, and the outputs of the above-mentioned sensors. an input section 4e equipped with a multiplexer for selectively outputting signals to the CPLJ 4a, an A/D converter for converting the analog signal 3 into a digital signal, and the like;
It also includes an output port (not shown), and an output section 4f which is provided with a drive circuit and the like for driving each of the above-mentioned foots according to a control signal from the CPIJ 4a as required. In addition, the ECU 4 connects each element such as the CPLJ 4a and the ROM 4b, the input section 4e, and the output section 4f, and a path line 4g to which each data is sent, and the ROM including the CPU 4a.
4b.

It has a Q-tock circuit 4h which sends a clock signal serving as a control timing to the RAM 4c etc. at predetermined intervals.

If the vehicle height sensors HI L, 1-11R, and H2C are the vehicle height sensors that output digital signals made up of a plurality of photo ink rubbers used in this example,
For example, as shown in Figure 6, the buffer? CPL via 4e
Can be connected to I4a. Also, for example, vehicle height sensors HI L, 1-11 R, H2C that output analog signals
In this case, the structure can be replaced with, for example, the structure shown in FIG. In this case, the vehicle height value is input to the ECU 4 as an analog voltage signal, converted to a digital signal by the A/D converter 4e2, and transmitted to the CPU 4a via the pass line 4g.

Here, the vehicle height replacement calculated values H, , I adopted in one embodiment of the present invention will be explained with reference to FIG.

The front wheel height sensor (ILll-11R described above) detects the distance between the wheel and the φ body as the vehicle height.The vehicle height is determined by the height of the vehicle around the normal vehicle height position, as shown in FIG. Displayed in 4 [bits] when the vehicle bounces, such as when riding on a protrusion, the vehicle height goes to the low position or to the extra low position.On the other hand, when the wheel rebounds, such as when the wheel rides down to a depression, the vehicle height goes to the high position or the extra high position, displayed in 4 bits. The relationship between the output value of the first height sensor and the vehicle height replacement calculated value H is defined by a map as shown in FIG.
is stored in advance in a predetermined area in the ROM 4b. The ECU 4 converts the output +a of the front wheel height sensors NIL and l-11R into a vehicle height replacement value HM based on the above map.
After converting it into , it is used for suspension control processing, which will be described later. It should be noted that the reason why the vehicle height displacement values near the extra-high position (which are similar to the extra-low position) are not specified at equal intervals is to prevent bottoming and the like.

Next, the relationship between vehicle height change, detection time, and determination time in one embodiment of the present invention will be explained with reference to FIG. 9. 9th
As shown in the figure, the time ts is 61t during the front wheel? 'I'
This is the detection time for the car to detect the output of L, l-11R.

In the case of this embodiment, for example, ++ such as 8 [m5CC]
It is ti. Further, the time T1 is a change determination rf period for determining whether or not to change the suspension characteristics. The time T1 is determined as shown in the following equation (1).

TI = (Nl-1)Xts...(1) However, N1
... Number of detected vehicle height data for change In this embodiment, N1 is 6
There are 4 [pieces].

When changing the suspension characteristics, first calculate the maximum vehicle height increase H1 within the change determination time from the maximum value HH and minimum value HL of the vehicle height within the change determination time T1 as shown in the following equation (2). put out

11=HH-1'' L... (2) Here, all vehicle heights are vehicle height replacement calculated values. This change γ11 Maximum vehicle height change within 1 hour] 1 is the change judgment small height reference value 1-
If it is 1k1 or more, the suspension characteristics are changed from a soft state (SOFT) to a sport state (SPORT), or from a sport state (SPORT>) to a hard state (IARD). The judged vehicle height performance semi-value Hk1 is 11 when expressed as a vehicle height replacement calculation value.

Further, time T2 is a return determination time for determining whether or not to restore the suspension characteristics to their original state. The time T2 is determined as shown in the following equation (3).

T2 = (N2-1) xts...(3) However,
N2...Return type i! ? ! Number of i-data detected In this embodiment, N2 is 126.

To restore the suspension characteristics to their original state, first calculate the maximum vehicle height change within the restoration determination time T2 (1ia l-(maximum vehicle height change within the restoration determination time from h and minimum value 11)-12 using the following formula (4). ) to shine like this.

H2= (h-1-1 sentence...〈4) Again, each vehicle height is the vehicle height level l! It is lyk calculation association. This return judgment II: If the vehicle height change maximum value within 'J ('2 is 2 or less than the return judgment car height standard value 11) three times in a row, the suspension characteristics will be changed to a sporty state! (SPOr<T
) to the soft state @<5OFT), and from the hard state (]"ΔRD) to the sport state fil (SPORT). In this example, the vehicle height standard 1a for return judgment is used.
Hk2 is expressed as -4 and 8 as calculated values for vehicle height.

Next, regarding the vehicle speed sensitivity adopted in this example, the first
This will be explained based on Figure 0. FIG. 10 is an explanatory diagram showing a map that defines the relationship between vehicle speed and suspension characteristics when driving on a rough road and when driving on a good road.As shown in FIG. If it is determined that the vehicle is traveling at a speed of 25 [1 v/h], the suspension characteristics will be in a soft state, and if it is in the process of acceleration, the suspension characteristics will be in a soft state.
v/hl to soft I-state, 40 [km/h] or more 1
Less than 00 [kll/h] is in sports state, 100 [kll/h]
[ki/h If it is 1 or more, it is set to the hard state.

In addition, when the vehicle speed is in the deceleration process in the range of 25 [1 v/h1 or more and 40 [km/h1] or more, the sport state is maintained. If it is determined that the vehicle is driving on a good road,
The suspension characteristics are soft when the vehicle speed is up to 70 [km/h], and when the vehicle speed is over 70 [1un/h] and 90 [km/h1]
Similarly, when the vehicle is in the m/h acceleration process, it is set to the soft state, and when the vehicle speed is over 90 [km/h] m/h, it is set to the sport state. In addition, if the vehicle speed is 70 [km/h] or more, 90
When the speed is less than [km/h] and the vehicle is in the 1st speed process, the sport state is maintained.

The reason why the settings of the suspension characteristics are changed depending on whether the vehicle is in the acceleration process or deceleration process as described above is because the history of changes in the suspension characteristics up to that point has been considered.

For example, after the vehicle speed increases by 90 [km/h] m/ due to driving on a rough road, the vehicle speed increases from 70 [km/h] to 90 [km/h].
When the vehicle speed decreases by h1m/m and then shifts to driving on a good road, the suspension characteristics are not immediately changed to a soft state in consideration of the history, but are maintained in a sport state.

Next, the suspension control system 6+1 process executed by the ECU 4 is shown in FIGS. 11 (A), (B), (C), and (D).
This will be explained based on the flowcharts shown in . This suspension control process is started when the driver selects auto mode (AUTO) after the vehicle starts and accelerates. First, an overview of this process will be explained.

(1) Detect the vehicle height at the vehicle height detection time tsfrJ, calculate the maximum vehicle height change value H1 within the change determination time T1, and determine the maximum vehicle height change 1a within the change determination time H1 is the change determination vehicle height standard If the value is 1 to 1 or more, the suspension characteristics are changed to a sport state (SPORT) or a hard state (HARD) according to the vehicle speed (steps 100 to 1).
160).

(2) Detect the vehicle height at every vehicle height detection time ts, determine the maximum value of the vehicle height change within the return judgment time 12 three times in a row, and calculate the maximum value of the vehicle height change within the return judgment time +1i11H2,
If all N3.144 are below the return judgment vehicle height base * value Hk2, the suspension characteristics are changed to soft state 11 according to the vehicle speed! (SOFT) is a sports state (SPOR)
T) (steps 200 to 534).

(3) If at least one of the vehicle height change maximum values H2, H3, and H4 within the return determination time in (2) above is equal to or greater than the return determination vehicle height reference value Hk2, the suspension characteristics are maintained according to the vehicle speed. or change (step 60
0-640).

Next, details of this process will be explained. In step 100,
Initialization processing is performed in which the minimum value 5 of the vehicle height displacement 1-IM is substituted for the vehicle height maximum value HMAX.

In the subsequent step 102, an initialization process is performed in which the maximum value 26 of the vehicle height replacement value H is substituted for the minimum vehicle height 'mHHHH. Next, in step 104, a process is performed to reset the change determination time timer TSZ for measuring the change determination time T1. In the following step 106, the change determination time timer TsZ starts measuring time! l! H'I! will be carried out. Next, in step 108, the vehicle height detection time (
A process of resetting the vehicle height detection time timer 1-5m for S measurement is performed. In the subsequent step 110, processing is performed to start counting the vehicle height detection time timer Tsm. Next, the process proceeds to step 112, where the vehicle height detection time timer T
A determination is made as to whether or not the count value of SI has become greater than the vehicle height detection time ts. If 31:00 of the vehicle height detection time timer Tsm is still not sufficient, the same steps are repeated while waiting. On the other hand, if the vehicle height detection time ts has elapsed, the process advances to step 114, and the front wheel height sensor H1
The output values of L and H1R are detected, and at the same time, a process is performed in which the output values are converted into vehicle height replacement calculated values and used as vehicle height data hn. Here, the front wheel height sensor HIL, l-(
The output value of the IR may be either the left or right value, or the average value of the left and right values or the larger value may be used. In the subsequent step 116, it is determined whether the vehicle height data old 1 exceeds the maximum vehicle height value t1-^x. If the vehicle height data hn is larger than 11tW height maximum 1 angle FI MAX, the process proceeds to step 118, where processing is performed to set the vehicle height data hn to the vehicle height maximum value HMl, and step 12
Proceed to step 4.

On the other hand, if the vehicle height data hn is less than or equal to the maximum vehicle height value HMAX, the process proceeds to step 120, where it is determined whether or not the vehicle height data hn is less than the minimum vehicle height value H)4t+J. If the vehicle height data hn is smaller than the vehicle height minimum value (vehicle height minimum value) - 1 μIN, the process proceeds to step 122, where processing is performed to set the vehicle height data hn to the vehicle height minimum value HHt,J, and step 124
Proceed to. In step 124, a change determination time timer Ts
A determination is made as to whether or not the counted value of z has become equal to or greater than the change determination time - 1. If the change determination time timer Tsz is still not measuring enough time, the process returns to step 108 and the width is again detected. On the other hand, change determination time T1
If the vehicle height has elapsed, the process proceeds to step 126, where a process is performed to calculate the maximum vehicle height change 1a)-11 within the change determination time by subtracting the minimum vehicle height from the maximum vehicle height.

Next, the process proceeds to step 128, where it is determined whether the maximum vehicle height change value H1 within the change determination time is greater than or equal to the change determination Φ high reference value)1. If the maximum change in vehicle height within the change determination time (1) is less than 1 in the change determination vehicle height reference value 14, it is determined that the change in vehicle height is small and the process returns to step 100. If the maximum vehicle height change value H1 within the determination time is greater than or equal to the change determination vehicle height reference value 11 by 1 or more, the process proceeds to step 130. In step 130, it is determined whether the vehicle speed V is 40 km/h'1 or more. It is determined whether the vehicle speed V is 40 [km/h] or not. If the vehicle speed V is 40 [km/h], the process returns to step 100. On the other hand, if the vehicle speed V is 40 [1 v/h]
] In the above case, the process proceeds to step 132, and a process of resetting the vehicle speed detection flag "90" is performed. The vehicle speed detection flag F90 is a flag that is set when the vehicle speed V once exceeds 90 [km/hl].Continued In step 134, it is determined whether the vehicle speed V is 90 [km/h1 or more]. If the vehicle speed V is 90 [km/h1 or more, the process proceeds to the summation block 136, where the medium speed detection flag F90 is set. A setting process is performed and the process proceeds to step 140.On the other hand, if the vehicle speed V is less than 90 [km/h], step 1
Proceed to 40.

In step 140, it is determined whether the vehicle speed ■ is greater than or equal to 100 km/h. q1st speed V is 100[k
m/h1 or more, proceed to step 142;
Processing is performed to change the suspension characteristics to a hard state (HARD) based on the map for driving on a rough road as described above. However, in step 142, processing is performed to reset the hard state change timer TpH9. Next step 144? ' is the suspension characteristics in the hard state (H
ARD) is started. That is, the rotary valve body 44b and the control rod 2 are operated by the actuators A1L, AIR, A2L, and A2H.
0 rotational drive is started. In the following step 146, a hard state change timer T1))10 is started at 51:00. Next, the process proceeds to step 148, where the count value of the hard state change timer T[)HC) is set to the hard state change constant 1-? It is determined whether or not it has become equal to or greater than loN.

It is set to change to the hard state @TNON (If the period has elapsed, proceed to step 150 and end the process of changing the suspension characteristics to the hard state (+-I A RD ). L, AI R,
Driving of A2L and A2R is stopped.

On the other hand, in step 140 above, the vehicle speed ■ is 100 [km/h]
If it is less than 1, the process proceeds to step 152, where a process is performed to change the suspension characteristic to sport mode 1 (SPORT>) based on the map during rough road driving described above.In other words, the actuators AI L, AI R1A
2L and A2R, the tarry valve body 44b and the control rod 20 are rotationally driven, and the spring constants and damping forces of the air suspensions SIL, SIR, S2L, and S2R are set to intermediate values. Step 152.154.156.158.160).

Next, the process proceeds to step 200, and below, processing is performed to calculate the maximum value H2 of the vehicle height change within the first return determination time T2 (steps 200 to 226).

Next, the process proceeds to step 300, and a process is performed to calculate the maximum value of the vehicle height change within the second return determination time T2 (steps 300 to 326).

Next, the process proceeds to step 400, and below, processing is performed to calculate the maximum value H4 of the vehicle height change within the 3ti'il return determination time T2 (steps 400 to 426).

Each of the above processes is substantially the same as the process of calculating the maximum value of the vehicle height change within the change determination time T1 described above, so a detailed explanation of each step will be omitted.

Next, in steps 500, 502, and 504, the maximum value H2, l of the vehicle height change within the return determination time T2 mentioned above is determined.
-13, [''4] It is determined whether or not the return determination vehicle height reference value Hk2 or more is F.

m large value of vehicle height change within return judgment time T2) -12
, 1-(3, a5 when H4 is all below the return judgment vehicle height reference value Hk2, it is determined that the mid-rest vibration has converged due to the change of the suspension characteristic, and the process proceeds to step 506 and below.Vehicle speed V is 90 [km/h] or more and the suspension characteristics are in the sport state (SPORT), the process returns to step 100 (step 50).
6.508). The vehicle speed ■ is 90 [km/h] or more, and the suspension characteristics are in a sport state (S P O
RT), if not, return the respension characteristics to the sports state (SPO1te"), and perform step 10 above.
Return to 0 (steps 506.508.510.512.
514.516.518) a Medium speed V is 90 [km/
h] less than 70 [kn+/h1, or if the vehicle speed V once exceeded 90 [tn+/h] in the past, the suspension characteristics are changed to a sporty state r/1 (SP0
17T), then return to step 100 (steps 506, 520, 522, 510, 512, 514).
．． 516.518.524). However, the vehicle speed V was 9 in the past.
0 [1v/h], the suspension characteristics are returned to the soft state (SOFT) and the process returns to step 100 (steps 506 and 520).
．． 522.524.526.528.530.532.
534). In addition, when the vehicle speed V is less than 70 [kil/h1], the suspension characteristics are changed to soft state fl (SOF
T), then return to step 100 (steps 506, 520, 526, 528, 530, 532.5).
34).

On the other hand, the maximum vehicle height change within return determination time T2 is 1+
If at least one of TH12, H3, and H4 exceeds 2 in the return determination vehicle height reference value 11, it is determined that the vibration of the vehicle body has not converged even after changing the suspension characteristics, and the process proceeds to step 600 or below. move on. Vehicle speed V is 10
0 [km/h] or more and the suspension characteristics are in the hard state (1-IARD), the process returns to step 200 (steps 600 and 60).
2). On the other hand, the suspension characteristics are in a hard state ()-1
If it is not in ΔRD), change the suspension characteristics to hard type rl (HARD), and then perform step 20 above.
Return to 0 (steps 600.602.604.606.
608, 610, 612). Also, the vehicle speed V is 100 [k
m/l+] less than 40 [km/h1 or more and the suspension characteristics are in the sport state (SPORT), the process returns to step 200 above (step 60
0.614.616). On the other hand, if the suspension characteristics are not in the sport state (SPORT), after changing the suspension characteristics to the sport state (SPORT),
Return to step 200 above (steps 600, 614.
616.618.620.622.624.626).

Furthermore, if the vehicle speed V is less than 40 [km/h] r25 [k
i/h], if the suspension characteristics are in the hard state (HA RD ), this is changed to the sport state (SPORT) and the process returns to step 200 (
Step 6001614.628.630.618.6
20.622.624.626). In addition, if the suspension characteristics are not in the hard state (]"ARD) state,
Return to step 200 above (step 600,
614.628.630). Also, the vehicle speed ■ is 25 [k
+++/h ] In the following cases, change the suspension characteristics to a soft state (80FT) and then perform step 10 above.
Return to 0 (steps 600, 614.628.632.
634.636.638.640). Thereafter, the tree suspension control process is repeatedly executed as the vehicle travels.

Next, an example of the control timing of the suspension control process will be explained with reference to FIGS. 12, 13, and 14. Figure 12 shows vehicle a hitting the road at a speed V [km].
/h ], the front wheel W1R1 (WIL) attempts to overcome an uneven road surface C, which is the beginning of a rough road. Furthermore, Figs. 13 and 14 show the output of the front wheel height sensor l-+1RSH11- and the υ suspension characteristic changing actuators AIR and A in the above case.
Changes in ILSA2R, A2L driving current and suspension characteristics are expressed over time.

As shown in FIG. 12, when the vehicle a is running on a flat road surface, the front wheel height sensor 1llL is changed from time (1 to time t2 after change determination time T11) as shown in FIG. 13. , (maximum vehicle height change detected from HIR)
10 is smaller than the change judgment small^ standard 11fiHkl. From time t2, as shown in FIG.
1R1 (WIL) begins to climb over the uneven portion C. Then, as shown in FIG. 13, from the same time t2 to the time t3 after the change determination time T1, the front wheel height sensor]1L,
The maximum vehicle height change value H1 detected from (H1R) becomes smaller than the change determination Mn"=Mt Hk 1. In this case, the maximum vehicle height value of the vehicle height data detected at each vehicle height detection time ts The vehicle height replacement values for the minimum vehicle height and minimum vehicle height are 21 and 10, respectively, and the maximum vehicle height change value 1''1 becomes 11, which is equal to the value 11 of the change determination vehicle height reference value 1. Therefore, at the same time t3, energization is started to the suspension characteristic changing actuators Δ1R, AllL, A2R1A2L, and the suspension characteristic is changed to the soft state (SOF) at time t4 after the suspension characteristic switching time Ta has elapsed.
T) to the sport state (SPORT). Note that the energization of each actuator is continued until time t5 after the actuator 1 energization time Tb has elapsed. On the other hand, since the suspension characteristics are changed to a hard state at time t4, the vibration of the vehicle body is suppressed, and the front wheel height sensor HI
The outputs of L and HIR show a damped vibration state as shown by the solid line in the same figure.The outputs of front wheel height sensor)-111 and l-11R when the suspension characteristics are not changed are shown in the same figure. It does not attenuate easily, as shown by the dashed line. Time t6 after the return determination time 2 has elapsed from the above-mentioned time t3
The vehicle height replacement values for the maximum vehicle height and minimum vehicle height up to are 2, respectively.
0 and 13, and the maximum vehicle height change value H2 is 7, which is the value 8 or less of 1 and 2. Furthermore, the vehicle height replacement calculated values of the maximum vehicle height and minimum vehicle height from time t6 to time t7 after the return determination time T2 has elapsed are each 20
and 13, and the maximum vehicle height change value t13 is 7, which is less than the value 8 of the vehicle height reference hti Hk2 for return determination. Further, 111 height position IIl of the maximum vehicle height and minimum vehicle height from time t7 to time t8 after the return determination time T2 has elapsed! The S value is
19 and 14, respectively, and the maximum vehicle height change value 114 is 5, which is less than or equal to the return determination vehicle height reference if Hk2 of 8. Therefore, at the same time t8, it is determined that the shooting during the mid-day break has ended, and energization of the suspension characteristic changing actuators A1R, Δ111A2R, and A2L is started. Suspension characteristic switching time Ta from the same time t8
At time t9 after the elapse of time, the suspension characteristics are returned from the sport state (SPORT) to the soft state (SOFT). Note that the energization of each actuator continues until time t10 after the actuator energization time Tb has elapsed.

Next, an example of the control timing when the vehicle speed (2) changes when the automobile 8 passes through an uneven portion C on the road surface will be explained based on the timing chart of FIG. 14. While car a is traveling on a flat road surface, the vehicle speed ■ is 90 at time t20.
Exceeds [km/h].

For this reason, the suspension characteristic changing actuator △1
[-1AIR, A2L, A21 are energized starting from C1,
At time t21 after the suspension characteristic switching time Ta has elapsed, the suspension characteristic changes to a soft state fi (SOF
T) to the sport state (SPORT). Next, at time t23, the front wheel WIL1WIR begins to ride over the uneven portion C of the road surface. Therefore, the maximum vehicle height change value T11 detected by the front wheel vehicle height sensor 1-111, ()IIR by 24 after the change determination time T1'IA from the same time t23 is change determination 1 quasi-4IIIHhi. Become bigger.

Also, the vehicle speed V at time t24 is 110 [km].
/hl. Therefore, at the same time t24, the suspension characteristic changing actuator A1R1Δ1l-1A
2R%A2+- is started to be energized, and at time t25 after the suspension characteristic switching time Ta has elapsed, the suspension characteristic is changed from the sport state (SPORT) to the hard state <HARD). Vehicle height change maximum value 1 (2) from time (24) to time t27 after return determination time 12
, time t2Q after return determination time T2 has elapsed from time t27.
The maximum vehicle height change value H3 from time t28 to time 6+B29 after the return determination time T2 has elapsed are both the vehicle height reference for return determination till l-1.
There are more than k2. Therefore, it is determined that the vibrations of the vehicle body have not converged, and the original suspension characteristics are not restored. However, at time t29, I was in J3 and the heavy speed V was 60.
The speed is expected to drop to [km/h].

Therefore, at the same time t29, the suspension characteristic changing actuators △1R1△IL, △2R.

At time t30 after the suspension characteristic switching time Ta has elapsed after energization of A2L starts, the suspension characteristic changes from the hard state (HA RD ) to the sport state (SP
ORT). Return determination time T2 from time t29
Vehicle height change maximum value H5 until time [32] after elapsed time, time 1
Vehicle height change maximum value 11G from 32 to time t33 after return determination time T2 has elapsed, from time t33 to return determination time T2
The maximum value H1 of vehicle height change up to time t34 after the elapse of time is all return judgment vehicle height MQ! The value will be 1-1 and 2 or less. Therefore, it is determined that the vibration of the vehicle body has converged, and moreover, the vehicle nv at time t34 has decreased by 50' [km/h]. Therefore, at the same time t34, the suspension characteristic changing actuator A1R1A1L.

Electrification is started to A2R and A2L, and at time [35] after the suspension characteristic switching time Ta has elapsed, the suspension characteristic changes from the sport state (SPORT) to the soft state @ (
SOFT>. Thereafter, while the tree suspension control process continues, the suspension characteristics are changed as appropriate depending on the road surface condition and medium speed.

In this embodiment, the right front wheel height sensor 11R, the left front wheel height sensor 1 (1L, ECtJ4 and the EC
Processing executed by U4 (steps 114, 214
, 314, 414) as the vehicle height detection means M1, the ECL
J4 serves as the determining means M2, and the suspension characteristic changing actuators AIR, AIL, Δ21. A2R and ECU
4 and the process executed by the ECU 4 (step 1
42,144°146.148,150,152,15
4,156.158,160,510,512.514
゜516.518,526,528,530,532.
534> respectively function as suspension characteristic changing means M3. Further, E14 and the processes executed by the ECU 4 (steps 100 to 128) are changed as the change determination means M4, and the processes executed by the ECU 4 and the ECU 4 (steps 200 to 226, 300 to 326, 400 to 42)
6,500, 502, 504> respectively function as the return determination means M5.

As explained above, in this embodiment, the front wheel height sensor HIL
, (HIR) is used to detect the vehicle height at each vehicle height detection time ts, and the maximum change in vehicle height within change determination time T1 is 111, and the change determination vehicle height is 1 or more in the l I'lf value 1-1. In this case, the suspension characteristics are changed from the sport state (S I ORT ) to the hard state ( ) l A RD ) according to the vehicle speed V at that time, and on the other hand, the maximum vehicle height change within the return judgment time 12 is (I issued a shift three times in a row, and the failure values H2, +13, and H4 are all the vehicle height reference values for return judgment (if they are less than 1 to 2, the resuspension characteristics are set to soft according to the vehicle speed at that time). It is configured to return to the state (SOFT) or sport state (SPORT). Therefore, depending on the change in vehicle height within change judgment 114 (T1), the suspension characteristics are returned to the sport state (SOFT).
(SPORT) or hard state (HA RD)
Since the vehicle is changed to a relatively used condition, the vibration of the vehicle body can be quickly reduced.

In addition, once the suspension characteristics are changed to a sport state (SPO
RT) or hard state < l-I A RD ), the vehicle height change at the return judgment time T2 is detected three times in succession, and the vehicle height change becomes the return judgment vehicle height reference hlIH.
When it becomes smaller than k2, the suspension characteristics return to the soft state (SOFT) or sport state (SPORT) depending on the vehicle speed V at that time, so it becomes possible to judge whether there is a continuous rough road or not. If it is determined that the road is continuous, the vehicle body photography is suppressed,
It is possible to continue the control so as to quickly attenuate the amount of water.

Furthermore, the change determination time T1 when the suspension characteristics are in a relatively soft state is set short, and the value of the change determination vehicle height reference value 1-1kl is set as large as 11. On the other hand, when the suspension characteristic is in a relatively hard condition f, the return determination time T2 is set to be long, and the value of the return determination vehicle height reference value 1''k2 is set to be as small as 8. However, the suspension control start condition targets vibrations with large amplitudes and short periods, while the control end conditions target vibrations with small amplitudes and long periods assuming that the above-mentioned vibrations are attenuated. A clear difference is provided between the control termination condition and the control termination condition. Therefore, it is possible to prevent hunting from occurring due to suspension characteristic change control.

Furthermore, with the above effect, the suspension characteristics are changed optimally, eliminating unnecessary changes Z11611, reducing the frequency of changes to the suspension characteristics changing actuators AIL, AlR.

The durability and reliability of Δ2L and A2R can be maintained at a high level.

Furthermore, in each case of driving on good roads and bad roads, l11
Since suspension control is performed based on a map that defines suspension characteristics related to speed V, it is possible to achieve optimal suspension characteristics corresponding to the medium speed V at that time even when driving on the same road surface. . This allows the vibrations of the vehicle body to quickly settle down, especially when driving.
It is effective in improving maneuverability and stability.

In addition, since the change determination time T1 is set shorter than the return determination means 2, when a light rain enters a rough road from a good road,
By quickly detecting the first impact caused by unevenness on the road surface and setting the suspension characteristics to a hard state, the initial large vibration can be quickly reduced and the occurrence of bottoming or hitting the rebound stopper can be prevented.

Due to the above effects, when a vehicle runs on a continuous rough road,
Alternatively, when the vehicle body is running with vibrations having a specific period, the suspension characteristics can be set to a hard state to suppress the vibrations and improve ride comfort, while also ensuring maneuverability and stability. It is possible to keep the vehicle running safely.Next, we will discuss other examples of suspension characteristics that can be used as a lower stage for changing suspension characteristics, other than air suspensions.

First, as a first example, as shown in FIGS. 15(a) and 15(b), the rigidity of the bushing used for connecting rod-shaped resuspension members such as the roll arm to the upper control arm and lower controller 1 of the suspension is changed. This shows a configuration in which the respension characteristics can be changed by having a mechanism.

Changing the rigidity means changing the spring constant and damping force in the bushing.

Fig. 15 (a) is a vertical cross-sectional view showing the connecting part of the rod-shaped suspension member 3, and Fig. 15 (b) is the line B-- of Fig. 15 (a).
FIG. In these figures, 901 designates a control arm extending along axis 9.02 and having a hollow bore 903. control arm 901
One end has an axis 904 perpendicular to the axis 902, and a hole 9
05 is welded around the hole 905. More fixed. There is a hole 9 in the sleeve 906.
An outer cylinder 908 with 07 is fixed by press fitting. An inner cylinder 909 is arranged inside the outer cylinder 890B concentrically with the outer cylinder, and a bushing 910 made of anti-vibration rubber is interposed between the outer cylinder 908 and the inner cylinder 909. Bushu 910
The hollow portions 9 cooperate with the outer cylinder 908 and extend in an arc shape around the axis 904 at positions facing each other along the axis 902.
11 and 912, thereby the axis 902
The stiffness in the direction along the direction is set to a relatively low value.

The hollow hole 903 of the control arm 901 has an axis 902
It constitutes a cylinder that supports the piston member 913 so as to be able to reciprocate along the piston member 913. Piston member 913 and hollow hole 9
A seal member 914 is used to seal between the wall surface 03 and the wall surface 03. An abutment plate 916 is fixed to one end of the piston member 913, which is curved around the axis 904 and extends along the axis 904 so as to come into close contact with the inner wall surface 915 of the cavity 911.

The other end of the control arm 901 also has the same structure as shown in FIGS. A cylinder chamber 917 is defined between the piston member and the piston member, which is not shown in the figures. The cylinder chamber 917 is communicated with the outside through a screw hole 918 provided in the control arm 901. Screw hole 9
18 has a nipple 923 fixed to the other end 922 of a 4-pipe 921 whose one end (not shown) is connected to a hydraulic pressure generation source, so that hydraulic pressure is supplied to the cylinder chamber 917. It is composed of

When the pressure of the oil in the cylinder chamber 917 is relatively low, the force pushing the piston member 913 to the left in the figure is also small, and the piston member 913 has a contact plate 916 that presses against the bush 91.
The bushing 910 is held at the illustrated position in light contact with the inner wall surface 915 of the bushing 910, so that the stiffness of the bushing 910 in the direction along the axis 902 is relatively low. On the other hand, cylinder chamber 9
If the hydraulic pressure inside 17 is relatively high, the piston member 913
is driven to the left in the figure, and the contact plate 916 is pushed 191.
Immediately press the inner wall surface 915 of the bushing 910,
Since the part between 16 and inner@909 is compressed and deformed,
The stiffness of the bushing 910 in the direction along the axis 902 is increased.

Since the above-mentioned rod-shaped suspension member is provided between the wheels and the suspension, suspension characteristics can be changed by controlling the hydraulic pressure in the cylinder chamber 917 (hydraulic pressure source and hydraulic pressure control valve, etc.). This is done by controlling it with an actuator.In other words, when the fluid pressure increases according to instructions from the ECU 4, the stiffness of the bushing 910 increases, and the suspension characteristics increase the damping force and the spring constant. , the lease pension characteristics become hard, making it possible to improve maneuverability and stability, and conversely, lowering the hydraulic pressure reduces shock.

Next, as a second example, FIGS. 16(a) and 16(b) show other configurations of bushings that have similar functions.

FIG. 16(a) is a cross-sectional view showing a bushing integrated with an inner cylinder and an outer cylinder as a bushing assembly;
FIG. 6(b) is a sectional view taken along line CC in FIG. 16(a).

Embedded inside the bushing 1005 are four telescopic hollow bags 1010 extending along the axis 1003 at equally spaced positions around the axis 1003. Four chamber spaces 1011 are defined extending along an axis 1003 equally spaced around the . Each hollow bag 1010 is fixed at one end to one end of a base 1012 also buried within the bushing 1005 by a clamp 1013, and each chamber space 1011 is communicated with the outside of the bush 1005 through the base 1012. One end of a hose 1015 is connected and fixed by a lamp 1014 to the (l!! end of the base 1012).The other end of each hose 1015 is compressed through an actuator such as a pressure side tall valve, although it is not shown in the figure. It is connected in communication with an air supply source, thereby allowing controlled air pressure to be introduced into each chamber space 1011.

When the actuator is actuated by the ECU 4, the air pressure within each chamber space 1011 can be changed, and thereby the stiffness of the bushing can be changed steplessly. In this way, the stiffness of the bushing can be changed as appropriate after a change in vehicle height at the front wheels is detected.

Next, FIGS. 17A to 17G show the configuration of a stabilizer as a third example.

Fig. 17 (a) is a perspective view (not showing the torsion bar set stabilizer) incorporated in an axle-type realispension of an automobile, and Fig. 17 (b) and Fig. 17 (c) are respectively Fig. 17 (a). Fig. 17 is an enlarged partial vertical sectional view showing the main parts of the example shown in the unconnected state and the connected state, respectively.
17(b) and 17(c) with the clutch removed, and FIG. 17(e) shows the main parts shown in FIG. 17(d). FIG.

In these figures, reference numeral 1101 indicates an axle housing that rotatably supports an axle 1103 connected to a wheel 1102. A pair of brackets 1104 and 1105 are fixed to the axle housing 1101 at positions spaced apart from each other in the vehicle width direction. +riioe is connected to the axle housing 1101.

The stabilizer 1106 consists of a stabilizer light 1107 disposed on the right side of the vehicle and a stabilizer left 1108 disposed on the left side of the vehicle, and the stabilizer light 1107 and the stabilizer left 1108 are selectively integrated with each other by a coupling device 1109. It is now connected to. Ends 1114 and 1115 of the rod parts 1110 and 1112, respectively, shown in FIG.
A protrusion 1117 and a hole 111 extending along l 116
8 is formed. These protrusions and holes are provided with male and female threads that are screwed together, respectively, so that the rod portions 1110 and 1112 are aligned with the axis 1116.
are connected to each other for relative rotation around the . Returning to FIG. 17(a) again, arm parts 1111 and 1113
are connected to brackets 1123 and 1124 fixed to side frames 1121 and 1122 of the vehicle by links 1119 and 1120, respectively.

As shown in FIG. 17(c), the coupling device 1109 includes a cylindrical clutch 1125 and one end 11 of a rod portion 1110.
14 and supports the clutch 1125 so that it cannot relatively rotate around the axis al 116 and can reciprocate along the axis 1116, and the rod part 111
2, the clutch 1125 is connected to the shaft F+
11116, and a clutch receiver 1127 which is received in a relatively non-rotatable manner around the clutch receiver 11116. D-L in Figure 17 (b)
) is a cross-sectional view. As shown in Figure 17(f),
The inner peripheral surface of the clutch 1125 is a plane 1 that faces each other on both sides of the axis 1116 and extends parallel to the axis 1116.
128 and 1129 and these planes as axis FA1116
cylindrical surfaces 1130 that connect to each other at opposite positions.
and 1131. Correspondingly, the outer circumferential surface of the crudge guide 1126 has planes 1132 and 1133 extending parallel to each other along the axis 1116 on both sides of the axis IllA 1116, and planes 1132 and 1133 extending parallel to each other along the axis 1116. It consists of cylindrical surfaces 1134 and 1135 that connect at these positions. Figure 17 (
D) As shown in (e), the outer peripheral surface of the clutch receiver 1127 has flat surfaces 1136 and 1137 facing each other on both sides of the axis 1116 and extending parallel to each other along the axis FIi 1116, as shown in Irj1. The plane is the axis 111
Cylindrical surface 113 connected to 6 at mutually opposing positions
8 and 1139.

As shown in FIG. 17(f), the flat surfaces 1132 and 1133 of the clutch guide 1126
113G and 1128 of the clutch receiver 1127, and when the clutch 1125 is in the position shown in FIG.
37 also correspond to planes 1129 and 1 of clutch 1125, respectively.
128 and thereby stabilizer light 110
7 and the stabilizer left 1108 are integrally connected around the axis 111G so as not to be relatively rotatable. As shown in FIG. 17(E), in particular, chamfers 1140 and 114 are formed on the ends of the flat surfaces 1136 and 1137 of the clutch receiver 1127 on the stabilizer light 11o7 side.
1 is applied, which allows the rod portion 1110 and 1
Even when the clutches 112 and 112 are slightly rotated relative to each other around the axis 1116, the clutch 1125
The stabilizer light 1107 and the stabilizer lights 1 to 1108 can be moved from the position shown in FIG. 17 (b) to the position shown in FIG. They are designed to be integrally connected to each other so as to exist in the same plane.

The clutch 1125 is reciprocated along an axis 1116 by an actuator 1142 controlled by the ECU 7I. As shown in FIG. 17(a), the actuator 1142 includes a hydraulic piston-cylinder device 1143 fixed to a differential casing (not shown) and an E-E in FIG. 17(b).
As shown in FIG.
Arm portions 1146 and 114 that engage 4 and 1145
7, which is connected to a piston rod 1148 of a piston-cylinder device 1143 shown in FIG. 17(A) to a fork 1149.

When the actuator 1142 moves the clutch 1125 to the position shown in FIG. By bringing out the mechanism and bringing it to a 1'7 state, rolling is reduced and maneuverability/
Stability can be improved. Further, when the actuator 1142 brings the clutch 1125 to the position shown in FIG. This reduces vehicle shock, especially on one wheel, and improves ride comfort.

Next, FIGS. 18(a) and 18(b) show an example of a Haku's stabilizer as a fourth example.

The assembly of the stabilizer bar set vA1310 in this example is the 18th
As shown in Figure (A), the first stabilizer bar 131
8 and a second stabilizer bar 1320. 1st
The stabilizer bar has a main body part 1322 and an arm part 132.
3 is on the right.

The main body portion 1322 is attached to the vehicle body by a pair of mounting brackets 1324 so that the body portion 1322 can be twisted around one engagement line.

The second stabilizer bar 1320 is formed in a hollow shape, as shown in FIG. Let me pass it through. This second
The stabilizer bar 1320 has a pair of mounting brackets 1324.
The first stabilizer bar 1318 can be connected and disconnected. In the illustrated example, a piston 1330 to which a spool 1328 is fixed is attached to one end of the interior of the second stabilizer bar 1320 with a sealing member 1
332 so as to be slidably arranged in a liquid-tight manner. This spool 1328 is made liquid-tight by a seal member 1334 and projects outward from the second stabilizer bar 1320.

The spool 1328 has a spline 1336 adjacent the piston 1330 while the second stabilizer bar 1
320 has a spline 1338 at one end that can engage spline 1336. The spool 1328 further includes a spline 134 on the inside of the outwardly projecting end.
has 0.

The coupler 13 is coupled to the body portion 1322 of the first stabilizer lever 1318 by a spline 1342.
44 is attached. The coupler 1344 has a spline 1340 at the end opposite the spool 1328.
It has interlockable splines 1346. In the illustrated example, the coupler 1344 is coupled to the mounting bracket 1324 via a rubber bushing 1345;
By deforming 345, the main body portion 1322 is configured to be torsionally deformed. coupler 1344
The attachment position is such that spline 1340 can engage spline 1346 when spool 1328 moves to the left and spline 1336 engages spline 1338. two splines 1340
．． Fragmented boots 1 that protect 1346 from dust
347 is the second stabilizer bar 1320 and coupler 1
344.

Piston 1330 of second stabilizer bar 1320
Two ports 1348.1 on both sides of the
350 is provided, and piping is provided so that pressure fluid can be guided to each port, and the port is put into use.

Now, when pressure fluid is introduced into the port 1350 through an actuator such as a hydraulic control valve, the piston 1330 moves to the left together with the spool 1328, and the spline 1336
spline 1338 and spline 1340 engage spline 1346, respectively. As a result, the first and second stabilizer bars 1318, 1320 are connected and the stiffness of the stabilizer bar assembly is increased.

Conversely, when pressure fluid is introduced into port h 1348, piston 1
330 moves to the right, the engagement of each spline is released, and the rigidity of the stabilizer bar 49 becomes only that of the first stabilizer bar 1318.

Next, FIGS. 19A to 19C show another example of the stabilizer as a fifth example.

The stabilizer 1410 of this example is shown in the schematic plan view of FIG. 19(a). Here, 1411 is a wheel, and 1412 is a suspension arm. It includes a main body 1414, a pair of arms 141G, and an extension means 1418.

The round bar-shaped main body 1414 is passed through bearing parts 1421 of a pair of links 1420 arranged at a distance of 47 in the width direction of the vehicle body, and is supported by the bearing parts 1421 so as to be able to twist around its axis. . Another bearing 422 at the upper end of the link 1420 is rotated by a pin 1428 passed through a bracket 1426 welded to the vehicle body 1424. ) + 7'iJ ability. As a result, the main body 1414 is arranged in the width direction of the vehicle body and can be twisted relative to the vehicle body.

In the illustrated example, the pair of arms 1416 are formed by flat rods, and the first ends 1430 of the arms 1416 are connected to the body 1414.
is connected at both ends by bolts and dogs 1432 for rotation about a vertical axis. second end 1
431 is arranged at a distance from this end portion 1430 in the longitudinal direction of the vehicle body. Here, the front-back direction includes a diagonal case.

Extension means 1418 extends from second end 143 of arm 1416.
1 in the width direction of the vehicle body. In the illustrated example, the extension means 1418 is constituted by a power cylinder.

As shown in FIG. 19(c), the power cylinder includes a cylinder 1434, a piston 1436 slidably disposed in the cylinder 1434 in a fluid-tight manner, and a screw 1-1.
A piston rod 1438 has one end connected to the cylinder 1436 and the other end projects outward from the cylinder 1434, and a piston rod 1438 that urges the piston 1436 in the direction in which the piston rod 1438 contracts.
A compression spring 1440 is provided. The piston 1436 is biased beyond a predetermined level by a stopper 1442 fixed to the piston.
is inhibited by

The cylinder 1434 is fixed to the suspension arm 1412 so that the piston rod 1438 is positioned outward in the width direction of the vehicle body.

The second end 1431 of the arm 1416 is connected to the outwardly projecting end 1439 of the piston rod 1438 by a bolt and a button 1432 so as to be rotatable about a vertical axis.

A flexible hose 1446 is connected to the liquid chamber 1444 on the opposite side of the cylinder 1434 from where the compression spring 1440 is located.
is connected at one end. This flexible hose 14
The other end of 46 is connected to hydraulic pressure 8 (not shown) via an actuator such as a hydraulic pressure control valve.

If no pressure is supplied to the fluid chamber 1444 of the power cylinder due to the state of the actuator according to the instructions of the ECU'l, the second end 1431 of the arm 1416 will move as shown in FIG.
Cover the position inward as shown in b). Therefore, the wheel rate of the stabilizer is low.

On the other hand, when the actuator is activated by the command of ECtJ4 and pressure is supplied to the liquid chamber 1444 of the power cylinder, the pressure moves to the piston 1436 and the piston rod 1438 is pushed out against the compression spring 1440. The second end 1431 of the stabilizer is pushed outward as shown by the two points vAa in FIG.

Next, as a sixth example, FIGS. 20(a) and 20(b) show the configuration of a coupling device between the stabilizer and the lower control arm.1. .

Figure 20 (a) is a partial front view showing a wishbone type suspension system incorporating the vehicle stabilizer according to this example, and Figure 20 (b) is shown in Figure 20 (a). FIG. In these figures, 1501 indicates a wheel rotatably supported by a knuckle 1503. The knuckles 1503 are each pivotally connected at an upper end to one end of an upper control arm 1507 by a pivot 1505, and are each pivotally connected to one end of a lower control arm 1511 by a pivot 1509 at a lower end. 17 control arm 1507 and lower control arm 1
511 are connected to a cross member 1517 of the vehicle by a bearing shaft 1513 and a pivot shaft 1515, respectively.

Further, in FIG. 20 (A), 151B indicates a U-shaped stabilizer arranged in the narrow width direction. Bracket 152
2 to the vehicle body 1524 so as to be rotatable about its axis. .

Tip 152 of arm portion 1520 of stabilizer 1518
0a are each coupled to a device proximate to one end of the lower control arm 1511 by a coupling device 1525 according to this example.

As shown in detail in FIG. 20(b), the connecting device 1
525 includes a cylinder piston device 1526. The cylinder piston device 1526 consists of two pistons 152 and a cylinder 530 that cooperate with the roof to define two cylinder chambers 1527 and 1528. The cylinder 1530 includes an inner cylinder 1532 that reciprocally receives a piston 1529 along an axis 1531, an outer cylinder 1533 arranged substantially concentrically with respect to the inner cylinder 1532, and an end cap that closes both ends of the inner cylinder and the outer cylinder. Members 1534 and 1
535 and more. The piston 1529 is the main body 15
36 and the arm portion 1 of the end main 1 shift member 1534 and the stabilizer 1518 carrying the main body 1536 at one end.
Hole 1538 provided at the tip of 520 Gi 1520 a
The piston rod 1537 extends along the axis 1531 through the piston rod 1537.

A rubber bush 1540 and a retainer 1541 for holding it are interposed between a shoulder 1539 formed on the screw rod 1537 and the tip 1520a, and a nut 154 screwed into the tip of the piston rod 1537 is inserted.
A rubber pusher 11543 and a rear end 1544 are interposed between the end 1520a and the end 1520a of the stabilizer 1518.

The end cap member 1535 has an axis 15 extending through a hole 1549 formed in the lower control arm 1511.
A rod 1546 extending along 31 is fixed. A rubber pusher 11547 and a retainer 1548 for holding it are interposed between the end cap member 1535 and the roller 1.1511.
A rubber push-piece L1550 and a retainer 1551 that holds it are interposed between a nut 1549 screwed into the tip of the D-rad 1546 and the lower control arm 1511, so that the rod 1546 is buffer-connected to the lower control arm 1511. has been done.

Inner cylinder 1532 is provided with L'3 through holes 1552 and 1553 at positions close to end cap members 1534 and 1535, respectively. The end cap member 1534 has a protrusion 15 that extends along the axis 1531 between the inner cylinder 1532 and the outer cylinder 1533 and comes into close contact with the inner cylinder and the outer cylinder.
54 is integrally formed. The protrusion 1554 has one end aligned with the N through hole 1552 and the other end aligned with the inner cylinder 1.
Annular space 15 between 532 and outer cylinder 1533
An internal passage 1556 is formed that opens into 55 . Thus, the through hole 1552, the internal passage 1556, the annular space 1
555 and the through hole 1553 are two cylinder chambers 1527
and 1528 are defined. Note that 14 people are filled with air in a part of the annular space 1555, and the cylinder chamber 1527 and the internal passage 1556
, a part of the annular space 1555 is filled with oil, and the volume change inside the cylinder of the piston rod 1537 caused by the relative displacement t of the screw 1529 with respect to the cylinder 1530 causes the change in the volume of the piston rod 1537 in the annular space 1555. It is compensated by the compression and expansion of the enclosed air.

Communication of the internal passage 1556 is selectively controlled by a normally open electromagnetic on-off valve 1557. The electromagnetic on-off valve 1557 has a solenoid 1558 inside and a housing 1559 fixed to the outer cylinder 1533 at one end.
a core 1561 disposed within the housing 1559 so as to be reciprocally movable along an axis rJ1560;
Figure (mouth) compression coil spring 1562 biasing to the right
It is becoming more and more. At one end of the core 1561 (Yo valve point 1
563 is integrally formed, and the valve element 1563 (
The projection 1554 is adapted to selectively fit into a hole 1564 formed across the internal passage 1556.

In this way, when the solenoid 1558 is not energized according to the instruction from ECIJ4, the core 1561 is compressed]
By being biased toward Ij1j in the figure by the oil spring 1562, the valve is opened as shown in the figure to correct communication of the internal passage 1556, and on the other hand, the solenoid 15 is
58 is energized, the core 1561 is driven to the left in FIG. The internal passage 1556 is configured to be disconnected from communication.

In the connection arrangement configured as described above, the solenoid 1558 of the electromagnetic on-off valve 1557 is energized to close the electromagnetic on-off valve, thereby cutting off communication between the cylinder chambers 1527 and 1528. The oil in the two cylinder chambers is prevented from flowing into each other through the internal passage 1556, etc., and this causes the piston 1529
The stabilizer 1518 is prevented from displacing relative to the cylinder 1530 along the axis 1531, thereby allowing the stabilizer 1518 to perform its original function (
J' and i are controlled, so rolling of the vehicle is suppressed and the maneuverability and stability of the vehicle when riding on one wheel or getting on and off are improved.

Also, if the solenoid 1558 is de-energized, the electromagnetic on-off valve 1557 is opened as shown in FIG.
The oil in 27 and 1528 flows freely into each other through internal passages 1556, etc., and 1! Therefore, piston 1529
can move freely relative to the cylinder 1530, and as a result, the tips of both the left and right arm portions of the stabilizer 1518 can move freely relative to the corresponding control arm 1511, so that the stabilizer This function reduces the shock to the middle wheel and ensures sufficient ride comfort.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it goes without saying that the present invention can be implemented in various forms without departing from the gist of the present invention. It is.

Effects of the Invention As described in detail above, the suspension control device of the present invention is capable of detecting when the maximum amount of change within the predetermined change time of the medium data obtained from the vehicle height detected by the vehicle height detection means is equal to or greater than the predetermined change determination value. The change determining means determines that the change ordinance falls under the change ordinance, and the suspension characteristics are changed by the suspension characteristics changing means, and on the other hand, the maximum change amount of the vehicle height data within the predetermined return time is less than or equal to the predetermined return judgment value. If this continues a predetermined number of times, it is determined by the return adjustment means that the return condition is met, and the suspension characteristic is returned to its original state by the first stage of suspension characteristic change. Therefore, it is possible to reliably detect vibrations of the vehicle body due to continuous driving on rough roads or vibrations of the vehicle body with a specific lap III, and to suppress the vibrations by changing the suspension characteristics to speed 15. Therefore, it is possible to realize suspension control that is suitable for the road surface conditions and vehicle posture, improving the riding comfort and improving the steering performance.・It has an excellent effect of being able to maintain a high level of stability.

Also inside? 3i-evening is determined by the change f111 means to correspond to the J:re change condition and the suspension characteristics are changed for one day. Therefore, since the start and end conditions for suspension control are different, hunting caused by control can be prevented, and the number of changes to the suspension characteristics can be minimized, making it possible to change the suspension characteristics. Improving the durability and reliability of actuators, etc. is f-I.
I become capable.

Furthermore, so-called semi-active control of the suspension, which changes the suspension characteristics according to road conditions, becomes possible. For this reason, when designing the Suspension, there is no longer a restriction that one of the suspension characteristics must be prioritized between ride comfort, maneuverability, and stability, and there is an advantage that the degree of freedom when designing the 4J suspension is increased.

For example, if the predetermined change 711 predetermined time is set to be shorter than the predetermined return judgment time, the high frequency vibration with a large vibration amplitude that occurs when the vehicle crosses from a good road to a bad road can be quickly removed. Since the suspension characteristics can be changed by detecting the vibration, it is possible to prevent the occurrence of so-called bottoming or hitting the rebound stopper caused by the vibration. It has good maneuverability and stability, making it possible to improve maneuverability and stability.

In addition, for example, if the change condition (i) applies, the resuspension characteristic changing means changes the suspension characteristic to a harder state II.
! If the configuration is changed to J, it becomes possible to quickly and quickly attenuate the vibrations of the vehicle body, and the maneuverability and stability of the vehicle are sufficiently guaranteed.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is an M water level block diagram conceptually illustrating the content of the present invention, Fig. 2 is a J system block diagram showing an embodiment of the present invention, and Fig. 3 is a diagram showing the present embodiment. FIG. 4 is a cross-sectional view of the main parts of the air suspension used in the example, FIG. 4 is a cross-sectional view taken along the line A in FIG. Figure 7 is a block diagram showing a digital vehicle height sensor signal input circuit; Figure 7 is a block diagram showing an analog vehicle height sensor signal input circuit; An explanatory diagram showing the map that defines the relationship with the replacement i value, Figure 9 is an explanatory diagram to explain the change determination conditions and return determination conditions, and Figure 10 is the relationship between vehicle speed and suspension 14. An explanatory diagram showing a map that defines
FIG. 11 (Δ), (B), (C). (D) is a flowchart showing the processing executed by the electronic control unit (ECU), FIG. 12 is a schematic diagram of the automatic vehicle of this embodiment overcoming uneven road surfaces, and FIG. 13 is the case shown in FIG. 12. Timing chart showing changes in front wheel height sensor output, suspension Tj characteristic change actuator drive current, and 1 suspension Tokuchiku, Figure 14 shows timing charts 1 to 1 when the vehicle speed changes.
Figures 15 to 20 show other examples of necks that change the suspension characteristics, Figure 15 (A) is a longitudinal sectional view of the first example, and Figure 15 (B) is its B-8 sectional view. , FIG. 16(A) is a cross-sectional view of the second example, FIG. 16(B) is a cross-sectional view taken along the line C-C, FIG. 17(A) is a perspective view of the third example in use, and FIG.
Figures 7(b) and (c) are respectively enlarged partial vertical sectional views of the third example, Figure 17(d) is a perspective view of the main parts, and Figure 17(e).
is a plan view of the same figure (D), FIG. 17 (F) is a sectional view taken along the line D-D in FIG. ) is a perspective view of the fourth example,
Figure 8 (b) is a partial enlarged vertical sectional view of figure (a), Figure 19 (a) is a schematic plan view of the fifth example, and Figure 19 (b) is the same figure (
Fig. 19 (c) is a sectional view of the extension means, Fig. 20 (a) is a partial front view of the sixth example (in historical use state), and Fig. 20 (b) is the same figure. It is an enlarged sectional view of (a)) and the notebook device. Ml...Small height detection means M2...Judgment means M3...The suspension characteristic changing means M4...Change judgment means M5...Return judgment means SIR, Sl 1. -, S2R, S2+-...Nearly Pension H1II, H11...Front wheel height sensor 1'' 2C・
・Rear wheel height sensor

Claims (1)

[Scope of Claims] 1. Vehicle height detection means for detecting the distance between the vehicle body and the wheels as the vehicle height, and vehicle height data obtained from the detected vehicle height that corresponds to a change condition or a return condition. and a suspension that changes suspension characteristics when the determination means determines that the vehicle height data falls under a change condition, and on the other hand, returns the suspension characteristics to the original when it is determined that the vehicle height data falls under a return condition. In the suspension control device, the determining means determines the change condition when the difference between the maximum value and the minimum value of the vehicle height data within a predetermined change determination time is equal to or greater than a predetermined change determination value. The change determination means determines that the change falls under the return condition if the difference between the maximum value and the minimum value of the vehicle height data within the predetermined return judgment time is equal to or less than the predetermined return judgment value for a predetermined number of consecutive times. A suspension control device comprising: a return determination means for determining that the condition is applicable. 2. The suspension control device according to claim 1, wherein the predetermined change determination time is set shorter than the predetermined return determination time. 3. The suspension control device according to claim 1, wherein the predetermined change determination value is set to be larger than the predetermined return determination value. 4. The suspension control device according to claim 1 or 3, wherein the suspension characteristic changing means changes the suspension characteristic to a harder state.