JPH0419213A - Stabilizer for vehicle - Google Patents

Abstract

PURPOSE:To improve a riding feeling by detecting the road surface state, and in the case of judging an uneven road, commanding the decrease of a command signal for adjusting the cylinder chamber pressure of a fluid pressure cylinder or the stop of operation. CONSTITUTION:A road surface judging means judges the road surface state on the basis of the detected information of a road surface state sensor. In the case of detecting an uneven road, a control retreating command means decreases a command signal computed by an internal pressure control means or stops operation. The internal pressure control quantity of a stabilizer is thereby reduced to become zero or prevented from further increase, so that the spring force and damping force of the stabilizer is lowered. As a result, the transmission of vibration caused by the irregularity of the road surface is prevented to suppress the aggravation of a riding feeling.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vehicle stabilizer device, and particularly to a device using a hydraulic stabilizer such as a hydraulic stabilizer.

[Prior art] Conventionally, as this type of device, for example,
The device described in No. 506 (name of the invention is "hydraulic stabilizer") is known.

This conventional device has single-rod, double-acting hydraulic cylinders installed in the vertical direction between the left and right suspension arms and the vehicle body, and between the left and right hydraulic cylinders, one upper cylinder chamber and the other cylinder chamber are connected to each other. The lower cylinder chamber is communicated with the lower cylinder chamber in a cross state through hydraulic piping, and orifices are inserted in the middle of each hydraulic piping, and the hydraulic piping portion between the upper cylinder chamber and the orifice of each hydraulic cylinder is
A spring mechanism that elastically biases the hydraulic oil is communicated.

(Problem to be Solved by the Invention) However, in the conventional device described above, the configuration was such that orifices with variable damping ratios were simply inserted into the middle of the cross-connected pipes, so rolls were suppressed during turning. As a result, the bouncing force and damping force are increased, so when the turning surface is on a rough road with unevenness, vibrations are transmitted from the road surface to the vehicle body, increasing the rugged feeling and significantly deteriorating the riding comfort.

The present invention was made in view of the problems of the conventional devices, and the problem to be solved is to determine whether the turning surface is a rough road or not, and if it is a rough road, to provide a good ride. The idea is to prioritize ensuring comfort.

[Means to solve the problem]

In order to solve the above problem, the invention as claimed in claim (1) uses double-acting hydraulic cylinders that are individually inserted between the left and right suspension links and the vehicle body, as shown in FIG. 1(a). Of these left and right fluid pressure cylinders, there is a conduit that interconnects the cylinder chamber of one cylinder and the cylinder chamber of the other cylinder, and a conduit that communicates with each of these conduits via a throttle valve and that elastically transmits the working fluid. A stabilizer device for a vehicle comprising a fluid chamber that repulses the fluid pressure cylinder, the internal pressure variable means being capable of changing the pressure of the cylinder chamber of the fluid pressure cylinder according to a command signal, and the command signal based on the turning state of the vehicle. a road surface condition sensor that outputs information corresponding to the road surface condition; a road surface determination means that determines whether the road is uneven based on the detection information of the road surface condition sensor; control retreat command means for commanding to decrease the command signal or stop calculation when the road is determined.

Further, the invention as claimed in claim (2), as shown in FIG. A pipe line that interconnects the cylinder chamber of one cylinder and the cylinder chamber of the other cylinder, and is connected to each pipe line via a throttle valve and elastically urges the working fluid. A vehicle stabilizer device comprising a fluid chamber, an on-off valve inserted between the pipes and capable of opening and closing the flow path, and a pressure in the cylinder chamber of the fluid pressure cylinder capable of changing in response to a command signal. an internal pressure variable means, an internal pressure control means that calculates the command signal based on the turning state of the vehicle, a road surface condition sensor that outputs information corresponding to the road surface condition, and an irregularity exceeding a predetermined value based on the detected information of the road surface condition sensor. road surface determination means for determining whether the road is uneven; and control retreat command means for suspending the calculation of the command signal and commanding the open state of the on-off valve when the road surface determination means determines that the road is uneven. There is.

[Operation] In the present invention, when there are irregularities on the turning surface, the road surface determination means determines that the road is uneven based on the detection information of the road surface condition sensor, so the control retreat command means is calculated by the internal pressure control means. Decrease the command signal or stop calculating the command signal. As a result, the internal pressure control amount of the stabilizer decreases, becomes zero, or no longer increases, and the spring force and damping force of the stabilizer decreases, making it difficult for vibrations caused by uneven road surfaces to be transmitted to the vehicle body. , deterioration of riding comfort is prevented.

In particular, in the invention described in claim (2), when it is determined that the turning surface is a rough road, control of the stabilizer device is stopped and the pipes are communicated with each other by an open state command of the on-off valve. . Therefore, the throttling effect due to conduit resistance is also reduced, and deterioration of riding comfort can be more reliably prevented.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 2 to 5 of the accompanying drawings.
This will be explained based on the diagram. In this embodiment, a hydraulic stabilizer is employed so that the roll rigidity generated auxiliary can be actively controlled according to the turning state.

In Figure 2, 2L and 2R represent the left and right wheels of the vehicle, respectively.
6 indicates a wheel support member, and 6 indicates a vehicle body.

One end of a suspension link 8 is swingably connected to the wheel support member 4, and the other end of the suspension link 8 is swingably connected to the vehicle body 6. A shock absorber 1 is provided between this suspension link 8 and the vehicle body.
0 and a coil spring 12 are provided.

Furthermore, in FIG. 2, 14 indicates a stabilizer device. This stabilizer device 14 includes a stabilizer body 1 provided between suspension links 8 of left and right wheels and a vehicle body 6.
4A, and a control section 14B that auxiliarily controls roll rigidity during turning by the stabilizer main body 14A.

The stabilizer main body 14A includes hydraulic cylinders 2OL and 2OR as fluid pressure cylinders, throttle valves 22A and 22B and accumulators 24A and 24B as fluid chambers, and an electromagnetic switching valve 25 as an on-off valve, and each of these elements are the first hydraulic pipes 26A, 26B and the second hydraulic pipes as pipes.
The structure is such that they are interconnected by hydraulic pipes 28A and 28B.

Each of the hydraulic cylinders 2OL and 2OR includes a cylinder tube 20a, a slidable piston 20b which separates the inside of this cylinder tube 20a into an upper cylinder chamber U and a lower cylinder chamber, and is fixed to this piston 20b. The piston rod 20c has a piston rod 20c extending in the axial direction. In each of the hydraulic cylinders 2OL and 2OR having such a structure, the lower end of the piston rod 20c is attached to the suspension link 8, the upper end is left free, and the cylinder at one end of the piston rod 20c is attached to the suspension link 8. The end portion of the tube 20a is swingably supported by the vehicle body 6, whereby hydraulic cylinders 2OL and 2OR are erected on the left and right upper and lower hinges, respectively.

Then, the upper cylinder chamber U of the left wheel side hydraulic cylinder 20L
is connected to the right wheel side hydraulic cylinder 2 via the first hydraulic pipe 26A.
The lower cylinder chamber of the left wheel hydraulic cylinder 2OL is connected to the upper cylinder chamber U of the right wheel hydraulic cylinder 2OR via the first hydraulic piping 26B. They are cross-connected to each other. Further, second hydraulic pipes 28A, 28B are connected to intermediate positions of the first hydraulic pipes 26A, 26B, respectively. The second hydraulic pipes 28A, 28B are connected to accumulators 24A, 24B, respectively, and throttle valves 22A, 22B are individually interposed in the middle of the pipes 28A, 28B.

Further, intermediate positions of the first hydraulic pipes 26A and 26B are connected to each other via an electromagnetic switching valve 25. The electromagnetic switching valve 25 is a normally open valve with two ports and two positions, and a solenoid control signal S is inputted to the solenoid from a controller to be described later.

On the other hand, the control section 14B includes a control cylinder 30 as an actuator that controls cylinder internal pressure, third hydraulic pipes 32A and 32B connected to this control cylinder 30, and an electric motor 34 that drives the control cylinder 30. The controller 36. Lateral acceleration sensor 38. and a road surface condition sensor 40.

Of these, the control cylinder 30 is configured as a double-rod double-acting type like the aforementioned hydraulic cylinders 2OL and 2OR, and has a cylinder tube 30a and the inside of this cylinder tube 30a separated into two cylinder chambers R1 and R2. and a slidable piston 30b, and this piston 30b.
The piston rod 30c is fixed to the piston rod 30c and extends in the axial direction. Among these, the cylinder chambers R1 and R2 are connected to the second hydraulic pipe 28A via the third hydraulic pipes 32A and 32B.
, 28B, respectively. Also, piston rod 3
One end of 0c is placed in a free state, and a rack 30 is placed on the other end.
d is formed. A pinion 34a of an electric motor 34 is engaged with this rack 30d.

Further, the lateral acceleration sensor 38 is installed at a predetermined position on the vehicle body, detects a positive and negative lateral acceleration signal G in the form of a voltage signal depending on the direction of the inertial force, and supplies the detected lateral acceleration signal G to the controller 36. The road surface condition sensor 40 is composed of, for example, a vertical acceleration sensor, an ultrasonic sensor, a stroke sensor between wheels and the vehicle body, and outputs a vertical acceleration signal or a distance signal corresponding to the unevenness of the road surface to the controller 36.

In this embodiment, the controller 36 includes a microcomputer, a motor drive circuit, a solenoid drive circuit, etc.
Detection signal G of lateral acceleration sensor 38 and road surface condition sensor 4
When a detection signal of 0 is input, the processing shown in FIGS. 3 and 4, which will be described later, is performed, and a motor drive signal i for driving the electric motor 34 and a solenoid control signal S for switching the switching valve 25 are output. Note that a rotation angle sensor (not shown) is attached to the electric motor 34, and a motor rotation position signal θR from this sensor is supplied to the controller 36.
Used to control the rotational position of the motor.

Next, the operation of this embodiment will be explained.

First, the process shown in FIG. 3.4 executed by the microcomputer of the controller 36 will be explained.

First, the process shown in FIG. 3 starts when the power is turned on. To explain this, in step (2) in the figure, the controller 360 microcomputer reads the detection signal G of the lateral acceleration sensor 40, stores the value, and then proceeds to step (2).

In step (2), in order to determine whether it is necessary to control the stabilizer device 14, it is determined whether the lateral acceleration G=0. If this judgment is rYEsJ, step■
Then, the solenoid drive signal S is turned off and the electromagnetic switching valve 25 is brought into the "open" state. As a result, the first hydraulic pipes 26A and 26B are brought into communication with each other.

On the other hand, if the determination in step ■ is "NO", it is determined that it is necessary to control the stabilizer device 14, and step
to move to. In step (2), the solenoid control signal S is turned on, contrary to step (2). As a result, the electromagnetic switching valve 25 enters the "closed" state, and the first. Second hydraulic pipe 26
A and 26B are cut off from each other.

Next, the microcomputer steps the process
Proceed to. In this step (■), the irregular road flag F=
Determine whether it is 1 or not. When the irregular road flag F is "1", it corresponds to an irregular road of a predetermined level or higher, and when it is "0", it corresponds to a good road or an uneven road surface close to this.

So, step 1. If the answer is "NO" in step (2), it is assumed that the road is not rough and the process moves to step (2), referring to the characteristic map stored in advance corresponding to the normal driving curve a in FIG.
A motor rotation angle command value Iθ, 1 (degree) corresponding to the read value G in step (2) is calculated. Curve a in the figure represents a command value 1θ9 (degrees) that increases by 3 to the proportional gain as the lateral acceleration G increases. Also, the proportional gain is large (k
, >k,) is set. In this embodiment, the curves a and b in FIG. 5 are linearly proportional to the lateral acceleration G, but it is sufficient that the command value 1θ9 during driving on a rough road is smaller than that during normal driving. The rate of increase may be gradually increased or decreased as the value increases.

On the other hand, if the determination in step (2) is rYES, it is assumed that the current turning surface is a rough road, and the process moves to step (2). In this step ■, the motor rotation angle command value 1θ, 1 corresponding to the read value G in step ■ is calculated by referring to the characteristic map stored in advance corresponding to the normal running curve in Fig. 5. do.

Motor rotation angle command value 1 at step ■ or ■ as shown in 2.
When θ and 1 are set, the process moves to step (2), and it is determined from the sign of 4MG read in step (2) whether the vehicle is turning to the right or not. In the case of rYEsJ in this judgment, steps ① to ② are processed. That is, the microcomputer outputs the motor drive signal i in the direction corresponding to the right rotation of the motor (clockwise direction in FIG. 2) in step (2). Next, in step [phase], the motor rotational position signal θR is input, and in step 2, the input signal θR is used to determine whether the electric motor 34 has rotated clockwise by a command value of 68 minutes. If "NO", the processes of steps (2) to (2) are repeated; if "rYEs", the motor rotation is stopped in step @, and then the process returns to step (2). by this,
The electric motor 34 rotates in the right direction by a command value θ4.

On the other hand, when "NO" is determined in step (2), steps (2) to (2) and (2) are performed in the same manner as steps (2) to (2). As a result, the electric motor 34 rotates to the left by the command value θ8.

Furthermore, the process shown in FIG. 4 will be explained. The process shown in the figure is executed by a timer interrupt process at fixed time intervals in the microcomputer of the controller 36.

In step (3) in FIG. 4, the controller 36 reads the detection signal of the road surface condition sensor 40 for a predetermined period of time. Next, the process moves to step (2) to perform road surface level calculation processing, and in step (2) it is determined whether or not the road is uneven. This series of rough road judgment processing is carried out, for example, as described in the conventionally well-known Japanese Patent Application Laid-Open Nos. 61-30408 and 61-37515.

Therefore, if it is determined in step (2) that the road surface does not exceed a predetermined level, that is, it is determined that the road is not rough, the process moves to step (2) and the rough road flag is set to F=O. On the other hand, if it is determined in step (2) that the road is uneven beyond a predetermined level, that is, the road is bad, the process proceeds to step (2) and the uneven road flag F is set to 1.

In this embodiment, the third hydraulic piping 32A, 32B control cylinder 3Q, electric motor 34. and solenoid switching valve 2
5 constitutes an internal pressure variable means, the lateral acceleration sensor 38 and the processing in steps ①, ②, ≈~■, ②~■ in Fig. 3 constitute an internal pressure control means, and the processing in Fig. 4 constitutes a road surface judgment means. death,
The processing of steps (2) and (2) in FIG. 3 constitutes a control retreat command means.

Next, the overall operation of this embodiment will be explained.

Assuming that the vehicle is traveling straight on a smooth road, the detection signal G of the lateral acceleration sensor is zero, so no rotation command is issued to the electric motor 34 through the process shown in FIG.
The solenoid control signal S=off, and the electromagnetic switching valve 25 is in an open (communicating) state. As a result, the piston position 30b of the control cylinder 30 maintains the neutral position,
Moreover, each piping and cylinder chamber U of the stabilizer 14,
The internal pressure of L is maintained at the same pressure. In this straight-ahead state, no bounce or rebound occurs in the wheels 2L, 2R, so no stroke change occurs in the left and right hydraulic cylinders 20L, 20R, and the piping 26A.

No flow of hydraulic oil occurs within 26B, 28A, and 28B.

Therefore, no spring reaction force is generated, and the throttle valve 22. A
, 22B and the flow path resistance of the pipes 26A, 26B, 28A, and 28B, no damping force is generated, and predetermined suspension characteristics are maintained.

Assume that while the vehicle is traveling straight, only one wheel 2L (2R) causes a stroke change due to running over a protrusion or the like. In this case, since the lateral acceleration is almost zero, the control cylinder 30 is in the neutral state as described above, and the electromagnetic switching valve 2
5 is in the open state, the internal pressure remains the same. Therefore, the shock absorber 10 of the wheel in which stroke fluctuation occurs generates a damping force based on a predetermined damping ratio. Along with this,
For example, by reducing the stroke of the hydraulic cylinder 2OL (2OR), the upper cylinder chamber U is compressed, and the hydraulic oil flows out. However, since the hydraulic cylinder 2OL (2OR) is a double rod type, the lower cylinder chamber is expanded by the same amount as the compressed volume, and the hydraulic oil flowing out from the upper cylinder chamber U is passed through the electromagnetic switching valve 25. and is absorbed into the lower cylinder chamber R of the same cylinder. In other words, the hydraulic fluid is in the throttle valve 22A.
(22B), almost no damping force is generated, and the ride quality is not impaired by the stabilizer device 14.

Furthermore, suppose that while the vehicle is traveling straight, both wheels bounce due to unevenness of the road surface. In this case as well, since the detected lateral acceleration value G is approximately zero, the control by the controller 36 is the same as described above. Therefore, the left and right shock absorbers 10 generate a damping force according to a predetermined damping ratio to accurately suppress vehicle body vibration. At the same time, if the wheel 2L passes through the convex portion.

2R bounces and both the pistons 20b of the hydraulic cylinders 20L and 20R try to move upwards in the vehicle body, the upper cylinder chambers U are compressed at the same time, and the lower cylinder chambers simultaneously shift to a negative pressure state. As a result, the hydraulic oil in the upper cylinder chamber U flows into the lower cylinder chambers of the self cylinder and the opposite cylinder through the first hydraulic piping 26A (26B). However, since the changes in volume of the upper and lower cylinder chambers U and L are equal due to the rod shape, the amount of oil in the second hydraulic pipes 28A and 28B does not change. This allows wheels 2L and 2R to pass through the recess.
The same is true when the lower cylinder chamber is compressed together with the rebound. Therefore, since the hydraulic fluid does not pass through the throttle valves 22A and 22B during both bounce and rebound,
Almost no damping force is generated, and no spring reaction force is generated. As a result, the damping force caused by the throttle valves 22A and 22B is not generated due to uneven road running accompanied by bounce, as in the conventional case, and the ride comfort is not impaired by the stabilizer device 14.

Furthermore, assume that the above-mentioned straight-ahead state has transitioned to a turning state on a good road. Assume that this turning is, for example, a right turning, and a roll occurs in which the left wheel 2L side sinks and the right wheel 2R side lifts up (see arrow A in FIG. 2) when viewed from the rear of the vehicle. During this turn, the lateral acceleration sensor 3
8 detects the inertial force and outputs a positive or negative lateral acceleration signal G to the controller 36 according to the turning direction. Therefore, the controller 36 closes the electromagnetic switching valve 25 based on the process shown in FIG. 3, and disconnects the first hydraulic pipes 26A and 26B from each other, thereby making each pipe 26A and 26B an independent system. moreover,
Since the controller 36 determines that the road is "good" through the process shown in FIG. 4, the motor rotation command value 1 during normal driving is
θ, 1 is set and commanded. As a result, the electric motor 34 rotates in the set direction (in the present example, clockwise in FIG. 2) and moves the piston rod 30c toward the left end in FIG. 1 by a command value of 68 minutes.

Therefore, the cylinder chamber R1 of the control cylinder 30 is compressed, the hydraulic oil inside the cylinder chamber R1 flows into the second hydraulic piping 28A side via the third hydraulic piping 32A, and the other cylinder chamber R2 is under negative pressure. become a state. Therefore, the internal pressure of the second hydraulic piping 28A, that is, the working pressure in the upper cylinder chamber U of the left-wheel hydraulic cylinder 2OL and the lower cylinder chamber of the right-wheel hydraulic cylinder 40R increases, and the hydraulic oil flows through the throttle valve 22A. It gradually flows through the accumulator 24A and is absorbed. On the other hand, the other accumulator 24
Hydraulic oil flows from the first.B through the throttle valve 22B. It is gradually supplied to the second hydraulic pipes 26A, 28A, the lower cylinder chamber of the left-wheel hydraulic cylinder 2OL, and the upper cylinder chamber U of the right-wheel hydraulic cylinder 20R.

In other words, while a splash reaction force is obtained, a damping force that resists sinking of the vehicle body is generated in the left-wheel hydraulic cylinder 20L due to the throttling effect of the throttle valves 22A and 22B, and a damping force that resists the sinking of the vehicle body is generated in the right-wheel hydraulic cylinder 2OR. The throttle effect of 22A and 22B generates a damping force that resists lifting of the vehicle body. This generates a moment that resists the roll in the direction A in the figure, and the roll is proactively suppressed in advance.

Since this moment is finely adjusted according to the magnitude of the lateral acceleration G that changes during the turn, it works together with the damping effect of the shock absorber 10 to accurately suppress the roll angle, and when the turn is completed, as described above. Automatically returns to neutral state for straight-ahead driving.

In the case of a left turn, the above-mentioned operations are the same, although the left and right directions are reversed.

Furthermore, assume that the vehicle turns on a rough, uneven road. in this case,
The controller 36 controls the electromagnetic switching valve 2 by the process shown in FIG.
5 is maintained closed, and since a "bad road" is determined by the process shown in FIG. 4, a motor rotation angle command value 1θM 1 when traveling on a rough road is set. This command value Iθ91 is a smaller value for the same lateral acceleration G than when turning on a good road (see the curve in FIG. 5). Therefore, when the electric motor 34 rotates based on the smaller command value lθM1, the amount of movement of the piston 30b of the control cylinder 30 is also suppressed to a smaller value than when turning on a good road, and as described above, it passes through the throttle valves 22A and 22B. The amount of oil is also small. As a result, the throttling effect of the throttle valves 22A, 22B is reduced, and the spring reaction force of the accumulators 24A, 24B is also reduced, so that the stabilizer device 14 keeps the generation of damping force and spring force to small values when traveling on rough roads. In other words, while roll suppression is entrusted to the shock absorber 10, the stabilizer device 14 exhibits soft damping force and spring force characteristics, so vibration transmission from the road surface is suppressed, resulting in worsening of riding comfort due to turning on uneven roads. is definitely prevented.

Note that in the configuration of the embodiment described above, the controller 3
The process shown in FIG. 3 carried out in step 6 may be changed as shown in FIG. 6 (corresponding to the invention described in claim (2)). In other words,
In the process shown in FIG. 6, the lateral acceleration signal G is read in step (2), and it is determined in step (2) whether the lateral acceleration G=O. In this judgment, if rYES, the command is given to open the electromagnetic switching valve 25 in step ■, and if rNo, the process moves to step ■, and the uneven road flag F is set in real time in the process shown in FIG. = 1 or not.

Then, if the judgment in this step ■ is "NO",
Assuming that the vehicle is turning on a good road, proceed to step ■, and switch valve 2.
Command 5 to close. Thereafter, the processing of steps ① to [phase] (same as the processing of steps ① and ① to ① in Fig. 3) is performed.

On the other hand, in the case of rYEsJ in the process of step (2), it is assumed that the vehicle is turning on a rough road, and the process moves to step (2), where the switching valve 25
Command to open and return to step ■. In other words, when turning on a rough road, the first hydraulic pipes 26A and 26B are communicated with each other and the control is also stopped, so the damping force generated by pipe resistance is reduced, and the entire stabilizer device 14 is This results in the softest damping and spring characteristics, further ensuring that ride comfort is prevented from deteriorating. Step (2) in FIG. 6 constitutes a control retreat command means.

Furthermore, in the process shown in FIG. 3 showing the above-mentioned embodiment, when rYEs, that is, a turning condition on a rough road is determined in step (2), it may be configured to directly return to step (2) (in this case, The process in step (2) in the figure is omitted, and the other processes are the same as in the figure). In other words, the first hydraulic piping 26A is closed by the electromagnetic switching valve 25 when judging the rough road.
26B is maintained in a non-communicating state, active control of the stabilizer device 14 is discontinued to prevent deterioration of riding comfort.

In the embodiment described above, the electromagnetic switching valve 25 as an on-off valve is provided between the first hydraulic pipes 26A and 26B, and when the stabilizer device 14 is not controlled, the switching valve 25 is
Although the switching valve 25 is set to the open state, it is also possible to remove the switching valve 25 (invention as claimed in claim (1)).
Although this generates a slight damping force when only one wheel goes over bumps, the configuration and control are simplified (
3), the roll suppression effect similar to that of the above-mentioned embodiment is exhibited, and the damping force and spring force are lowered when driving on rough roads, improving ride comfort. Deterioration is prevented.

Furthermore, in such a configuration in which the switching valve 25 is not installed, the rotation of the electric motor 34 may be stopped when turning on a rough road, that is, the damping force and spring force control may be stopped. As a result, active damping force and spring force are no longer generated, resulting in the softest stabilizer characteristics and preventing deterioration of riding comfort.

Further, the internal pressure control means in the present invention is configured to directly detect lateral acceleration using a sensor, but this is based on a vehicle speed detection signal and a steering angle detection signal, for example,
The lateral acceleration may be estimated using the method disclosed in Japanese Patent No. -293167.

Further, the double-acting hydraulic cylinder used in the present invention is not limited to the double-rod type as described above, but may be a single-rod type. In addition, the wheel side of the fluid pressure cylinder,
The mounting positions on the vehicle body side can be set in opposite directions on the left and right sides of the vehicle, so that the pipes connecting the fluid pressure cylinders appear to be parallel connections instead of cross connections. Furthermore, the fluid chamber of the present invention may be constructed using a spring that biases the piston as an elastic mechanism in addition to the actuator.

Furthermore, the working fluid in the present invention is not limited to the one using hydraulic oil as described above, and for example, incompressible gas may be used as the working fluid.

〔Effect of the invention〕

As explained above, in the present invention, it is determined whether or not the road is uneven based on information corresponding to the road surface condition output from the road surface condition sensor, and when it is determined that the road is uneven, the command signal for internal pressure control is reduced or Therefore, when the turning surface is uneven, the spring force and damping force of the entire stabilizer are forcibly reduced and corrected, making it difficult for vibration input from uneven road surfaces to be transmitted to the vehicle body. As a result, unlike conventional devices, it is possible to accurately prevent a decrease in ride comfort caused by turning on an uneven road.

In particular, in the invention described in claim (2), roll stiffness control is stopped when turning on an uneven road, and the pipes connecting the cylinder chambers of each fluid pressure cylinder are communicated with each other via the on-off valve. , the damping force and spring force generated by the pipe resistance are further reduced, and the reduction in riding comfort is more reliably prevented.

[Brief explanation of the drawing]

Figures 1 (a) and (b) are claims correspondence diagrams of the claimed invention;
5 to 5 are diagrams showing an embodiment of the present invention,
Fig. 2 is a schematic configuration diagram, Figs. 3 and 4 are schematic flowcharts showing an example of processing in the controller, and Fig. 5 shows an example of characteristics of the motor rotation angle command value during normal driving and when driving on a rough road. The graph in FIG. 6 is a schematic flowchart 1 showing a processing example in another embodiment of the present invention. Main symbols in the figure are 6...vehicle body, 8... suspension link, 14... stabilizer device, 20L. 2OR... Hydraulic cylinder, 22A, 22B... Throttle valve, 24A 24'B... Accumulator, 25.
...Solenoid switching valve, 26A, 26B...First hydraulic pipe, 28A28B...Second hydraulic pipe, 30...Control cylinder, 32A, 32B...Third hydraulic pipe, 34...・Electric motor, 36...controller,
38... Lateral acceleration sensor, 40... Road surface condition sensor, U... Upper cylinder chamber, L... Lower cylinder chamber,
It is. Figure 1 (G)

Claims (2)

[Claims] (1) A double-acting hydraulic cylinder that is individually inserted between the left and right suspension links and the vehicle body, and a cylinder chamber of one cylinder and a cylinder chamber of the other cylinder of the left and right hydraulic cylinders. a conduit interconnecting the
In the vehicle stabilizer device, the pressure in the cylinder chamber of the fluid pressure cylinder is controlled in accordance with a command signal in a vehicle stabilizer device including a fluid chamber that communicates with each of the pipes via a throttle valve and elastically urges the working fluid. a changeable internal pressure variable means; an internal pressure control means that calculates the command signal based on the turning state of the vehicle; a road surface condition sensor that outputs information corresponding to the road surface condition; A stabilizer for a vehicle, characterized in that it is provided with a road surface judgment means for judging whether or not the road is uneven, and a control retreat command means for instructing to reduce the command signal or stop calculation when the road surface judgment means judges that the road is uneven. Device. (2) Double-acting fluid pressure cylinders individually inserted between the left and right suspension links and the vehicle body, and the cylinder chamber of one cylinder and the cylinder chamber of the other cylinder of the left and right hydraulic cylinders. a conduit interconnecting the
In a vehicle stabilizer device that is provided with a fluid chamber that communicates with each of the pipes via a throttle valve and elastically urges the working fluid, the fluid chamber is inserted between the pipes and is capable of opening and closing the flow passages. an on-off valve, an internal pressure variable means that can change the pressure in the cylinder chamber of the fluid pressure cylinder according to a command signal, an internal pressure control means that calculates the command signal based on the turning state of the vehicle, and information corresponding to the road surface state. a road surface condition sensor that outputs a road surface condition sensor, a road surface judgment means that judges whether or not the road is uneven exceeding a predetermined value based on the detection information of the road surface condition sensor, and a road surface judgment means that outputs the command signal when the road surface judgment means judges that the road is uneven. A stabilizer device for a vehicle, comprising: a control retreat command means for stopping calculation and commanding an open state of the on-off valve.