JP3243076B2 - Vehicle roll control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roll control device for suppressing rolling that occurs on a vehicle body due to lateral acceleration acting on the vehicle body during running of a vehicle such as an automobile.

[0002]

2. Description of the Related Art Conventionally, in order to suppress rolling generated on a vehicle body of a running vehicle, a stabilizer of a variable hydraulic pressure type, for example, as disclosed in Japanese Patent Application Publication No. 24609 in 1986, has been used.

[0003] In other words, in this device, a torsion bar portion of a stabilizer for connecting suspension arms of left and right wheels is divided into two parts, one of which is divided into a housing side of a hydraulic rotary actuator and the other is divided into a rotor side. To each other.

[0004] Then, pressure hydraulic oil is selectively fed to the rotary actuator to apply a rotational torque in two forward and reverse directions. By applying force, a rotational moment in the roll direction is applied to the vehicle body.

Thus, when the vehicle rolls, for example, when the vehicle is turning, pressure hydraulic oil is sent to the rotary actuator, and the roll moment acting on the vehicle body by centrifugal force is applied to the vehicle by the rotary actuator. And the roll of the vehicle body is suppressed.

[0006]

However, according to the above-mentioned prior art, it is possible to increase the rigidity of the stabilizer by sending pressure hydraulic oil to the rotary actuator when necessary, thereby suppressing the roll generated on the vehicle body. However, there is no disclosure as to how this effectively corresponds to the magnitude of the centrifugal force applied to the vehicle body according to the running conditions at that time and how to effectively suppress the roll acting on the vehicle body.

[0007] From this, it is unsolved how to effectively suppress only the rolls acting on the vehicle body without impairing the riding comfort in actual application to the vehicle, and it is not practically used as it is. There was a problem that it could not be provided.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a roll control device for a vehicle using a variable hydraulic stabilizer of this type which has a simple hydraulic circuit and a control device, and which has an energy-saving and fail-safe effect. is there.

[0009]

Means for Solving the Problems To achieve the above object, the present invention provides a variable hydraulic stabilizer which is divided into two parts by a torsion bar and connected by a rotary actuator, and a hydraulic pressure for operating the rotary actuator. And a switching valve for holding the differential pressure control valve and the hydraulic source in an unloaded state at a normal position in the middle of a hydraulic circuit connecting the hydraulic source and the rotary actuator, and a switching valve for keeping the rotary actuator on the stabilizer side in a blocked state. A roll control device for a vehicle, which is provided in series with a control device for switching and controlling the differential pressure control valve and the switching valve by a lateral acceleration signal, wherein the differential pressure control valve has a supply port and a discharge port. And a valve housing having two control ports as output ports. A control spool which is slidably inserted into the jing by defining back pressure chambers at both end surfaces thereof, and a base end of a reaction force pin slidably inserted into one end of the control spool is brought into contact with the valve housing. A feedback chamber formed in the control spool, a spring is provided between the end face on the reaction pin side with respect to both end faces of the control spool and the valve housing, and the opposite end face is provided with a spring. An electromagnetic solenoid for switching the control spool while applying a thrust to the end surface and cooperating with the spring is provided, and of the two control ports, the thrust of the electromagnetic solenoid overcomes the spring to switch the control spool. In this case, the control port on the high pressure side is connected to the feedback chamber, and the other control port on the low pressure side is connected to the back pressure chamber. It is characterized in that the.

[0010]

[0011]

[0012]

In other words, according to the above configuration, if the control device applies a reference current to the differential pressure control valve in advance and holds the differential pressure control valve in a control state of zero differential pressure,
During normal operation when lateral acceleration is not applied to the vehicle body such as when traveling straight, the differential pressure control valve blocks the rotary actuator in the stabilizer with the switching valve while maintaining the state of zero differential pressure, and the stabilizer performs normal operation. Become.

At the same time, the hydraulic pressure source is also kept in the unloaded state by the switching valve, thereby saving energy.

On the other hand, when a lateral acceleration acts on the vehicle body such as when turning, the control device detects the magnitude of the lateral acceleration and generates a lateral acceleration signal (control current signal) corresponding thereto. The switching valve is switched to the open state by the signal, and the proportional control valve is controlled to perform a differential pressure corresponding to the magnitude of the lateral acceleration signal to the rotary actuator of the stabilizer.

Thus, the rotary actuator is
Through the stabilizer, a roll moment in a direction opposite to the roll moment acting on the vehicle body due to the centrifugal force at that time is applied to the vehicle body, and the roll generated on the vehicle body is effectively suppressed.

When the vehicle returns to a normal state such as straight running again, the lateral acceleration signal from the control device disappears, and the differential pressure control valve and the switching valve are switched to the original switching positions. As described above, the stabilizer performs the normal operation, and the hydraulic pressure source is also in the unload state.

In the above, when an abnormal situation occurs such that the reference current of the control device becomes zero, the differential pressure control valve performs a maximum control operation on one side to apply the maximum differential pressure to the rotary actuator. Take the position to add.

In this state, when a roll moment in the same direction as the roll direction by the rotary actuator acts on the vehicle body in this state, the vehicle body is greatly inclined in that direction by the synergistic action of these two rolls, and in an extreme case, the vehicle body is overturned. It could cause an accident.

However, at this time, since the switching valve always assumes the normal position, the rotary actuator is blocked by the switching valve, and the stabilizer performs a normal operation to suppress the roll of the vehicle body.

At the same time, the hydraulic pressure source is also kept in the unloaded state by the switching valve, thus achieving energy saving and a fail-safe effect.

[0021]

FIG. 1 systematically shows an embodiment of a roll control device according to the present invention. Both front and rear wheel stabilizers 1f and 1r are constituted by dividing a torsion bar portion into two parts at the center. One of the divided portions is fixed to the housing side of the hydraulic rotary actuators 2f and 2r, and the other is fixed to the rotor side.

In this embodiment, as shown in FIG. 2, the rotary actuators 2f and 2r have one inside.
Housing 4 provided with partition walls 3a and 3b at intervals of 80 degrees
The rotor 6 having the two vanes 5a and 5b is rotatably housed in the housing 4 at the same interval of 180 degrees.

The rotor 6 has a central portion in the housing 4.
Of the partition walls 3a and 3b, and the tip ends of the vanes 5a and 5b are slidably contacted with the inner wall of the housing 4.
a, 7b and 7c, 7d.

Of these four oil chambers 7a to 7d, diagonally located oil chambers 7a and 7c and oil chambers 7b and 7d communicate with each other through through holes 8a and 8b formed in the center of the rotor 6. In addition, the housing 4 is provided with ports 9a and 9b that open to the oil chambers 7a and 7b.

As can be seen from FIG. 1, the ports 9a and 9b of the rotary actuators 2f and 2r are connected to a hydraulic source 1 composed of a hydraulic pump 12 and a reservoir 13 through a hydraulic circuit 11 composed of pipelines 10a and 10b.
It leads to 4.

In the middle of the hydraulic circuit 11, the differential pressure control valve 15 and the hydraulic source 14 are held in the unloaded state at the normal position, and the pipelines 10a, 10b toward the ports 9a, 9b of the rotary actuators 2f, 2r are connected. A switching valve 16 for keeping a block state is provided in series.

In the above, the switching valve 16 is constituted by an extremely popular spring offset type electromagnetic valve which has been widely and conventionally used in various hydraulic circuits, and is small in size and suitable for in-vehicle equipment. In addition, since the configuration is well known, detailed description is omitted here.

However, since the differential pressure control valve 15 used in this embodiment is made smaller and lighter than the conventional one, especially in consideration of the use in a vehicle, the configuration thereof will be described below.

The differential pressure control valve 15 in this embodiment
Is provided with a valve housing 20 having a supply port 21 and a discharge port 22 and first and second two control ports 23 and 24 as shown in FIG.

An axially extending valve hole 25 is formed in the center of the valve housing 20. Three annular grooves 26, 27 and 2 are formed in the inner wall of the valve hole 25.
8 are formed respectively.

The three annular grooves 26, 27 and 28
The annular groove 26 located at the center of the
1 through the line 10a to the hydraulic pump 12 of the hydraulic source 14 in FIG. 1, and the remaining two annular grooves 27 and 28 also from the discharge port 22 through the line 10b to the reservoir 13 of the hydraulic source 14. .

The portions of the lands 29 and 30 located between the annular grooves 26 and 27 and between the annular grooves 26 and 28 are directed toward the switching valve 16 through the first and second control ports 23 and 24, respectively. The pipes 10a and 10b communicate with each other.

A control spool 36 having lands 31, 32 and 33 and annular grooves 34 and 35 therebetween is slidably inserted into the valve hole 25 of the valve housing 20.

In this embodiment, the control spool 36 is
It is configured as an underlap type, and the valve holes 25 are formed on the left and right back pressure chambers 37, 38 on the respective surfaces at both ends.
And these back pressure chambers 37, 38 are provided with passages 40a, 40b having damping orifices 39a, 39b on the way.
Are both connected to the second control port 24.

A hole 41 with a bottom is formed in the control spool 36 along the axis from the end surface on the side of the back pressure chamber 38, and a reaction force pin 42 extends from the open end of the hole 41 toward the inside.
Is slidably inserted, and a proximal end of the reaction force pin 42 abuts on the valve housing 20 to partition the feedback chamber 43 in the hole 41 with the reaction force pin 42 and to divide the feedback chamber 43 into a control spool. A through hole 44 formed in 36 communicates with the first control port 23 from the annular groove 34.

On the other hand, a spring 45 is applied between the end face on the reaction force pin 42 side and the valve housing 20 with respect to both end faces of the control spool 36, and a thrust is applied to the end face on the opposite end face. An electromagnetic solenoid 15a for switching the control spool 36 in cooperation with the spring 45 is provided.

The differential pressure control valve 15 and the switching valve 16
As shown in FIG. 1, the control device 17 for controlling the operation of the vehicle comprises a controller 18 and a lateral acceleration detector 19 for detecting a lateral acceleration acting on the vehicle body.

The output end of the controller 18 in the control device 17 is connected to the electromagnetic solenoid 15a of the differential pressure control valve 15 and the electromagnetic solenoid 1 for operating the switching valve 16.
6a, the control device 17 controls switching between the differential pressure control valve 15 and the switching valve 16.

The lateral acceleration detector 19 includes:
The lateral acceleration sensor may be provided on the vehicle body, or the vehicle speed and the steering angle may be detected, and the lateral acceleration acting on the vehicle body may be estimated from these.

Next, the operation of the vehicle roll control device according to the present invention configured as described above will be described.

First, referring to FIG.
Let F be the thrust of the electromagnetic solenoid 15a, W be the restoring force of the spring 45, a be the cross-sectional area of the reaction force pin 42, and Pa and Pb be the hydraulic oil pressures of the first and second control ports 23 and 24, respectively. The balance condition expression for keeping the control spool 36 stationary is “F = W + a (Pa−P
b) ".

Therefore, when the hydraulic oil pressures Pa and Pb of the first and second control ports 23 and 24 are the same (zero differential pressure) and "Pa = Pb", the feedback that is in communication with the first control port 23 is provided. The hydraulic oil pressure in the back pressure chambers 37 and 38 communicating with the chamber 43 and the second control port 24 is also “Pa = Pb”.
Therefore, the balance condition of the control spool 36 at that time is “F = W”.

From this, if the control current I flowing through the electromagnetic solenoid 15a through the controller 18 and the reference current im are passed so that the thrust F of the electromagnetic solenoid 15a becomes equal to the restoring force W of the spring 45, the control spool 36 Holds the neutral position shown in FIG. 3 while the forces acting on both ends cancel each other, and the stationary state is maintained, whereby the hydraulic oil pressures Pa and Pb of the first and second control ports 23 and 24 are reduced. The differential pressure of the same pressure is kept at zero.

As a result, there is no pressure difference between the hydraulic oil pressures Pa and Pb between the first and second control ports 4 and 5, so that the rotary actuators 2f and 2r of the stabilizers 1f and 1r shown in FIG. No rotational force in the direction works.

Here, from the above state, the controller 18
When the control current I flowing through the electromagnetic solenoid 15a through the solenoid is increased to increase the thrust F of the electromagnetic solenoid 15a to the thrust Fi, the balance condition of the control spool 36 collapses as "Fi>W", and the control spool 36 collapses. The switch 36 switches rightward in FIG. 3 while pressing and contracting the spring 45 in accordance with the increase Δf (= Fi−F) of the thrust of the electromagnetic solenoid 15a.

The switching operation of the control spool 36 increases the opening area between the lands 29 and 31 and the lands 30 and 33 in the valve housing 20 and the control spool 36, and conversely, the lands 29 and 32 and The opening area between the lands 30 and 31 is reduced.

As a result, the hydraulic oil pressure Pa of the first control port 23 increases, and the hydraulic oil pressure Pb of the second control port 24 decreases, and the feedback chamber 43 and the two back pressure chambers 37 communicating therewith. , 38, the differential pressure Δp (= Pa−
Pb) occurs, and a thrust force S (= Δp × a) acting in the opposite direction to the switching direction acts on the control spool 36 due to the differential pressure Δp.

Thus, the sum of the thrust force S due to the differential pressure Δp and the increase Δw of the restoring force W of the spring 45 due to the displacement of the control spool 36 is equal to the increase Δf of the thrust of the electromagnetic solenoid 15a. When they become equal, that is, when “Δf = Δw + Δp × a”, the balance is stopped, and the rotary pressure of the stabilizers 1f, 1r is maintained by maintaining the state of the differential pressure Δp between the first and second control ports 23, 24. A rotational force is applied to the actuators 2f and 2r in a predetermined direction.

Conversely, if the control current I flowing to the electromagnetic solenoid 15a through the controller 18 is reduced, the control spool 36
The spring 45 according to the decrease of the thrust of 5a “−Δf”.
The switch operation is performed to the left while being pushed by, and the operation is counterbalanced and stopped when "-.DELTA.f =-. DELTA.w-.DELTA.p.times.a" by the action opposite to the above, and the first and second control ports 23, 2 are stopped.
4 while maintaining the differential pressure “−Δp” between them.
A reverse rotational force is applied to the rotary actuators 2f, 2r of f, 1r.

In any of these cases, if the control current I flowing to the electromagnetic solenoid 15a through the controller 18 is returned to the original current im, the control spool 36 switches to the neutral position and The differential pressure Δp between the second control ports 23 and 24 becomes zero, and the rotational force applied to the rotary actuators 2f and 2r disappears.

Thus, the first and second control ports 2
As shown in FIG. 4, the pressure difference Δp between the solenoids 3 and 24 is adjusted in accordance with the change in the control current I to the electromagnetic solenoid 15a, and is applied to the rotary actuators 2f and 2r of the stabilizers 1f and 1r. And the differential pressure Δp
Will be applied.

From this, when the vehicle is in a straight running state and there is no detection signal from the lateral acceleration detector 19, the controller 18 supplies a reference current im to the electromagnetic solenoid 15a of the differential pressure control valve 15, The solenoid valve 16a of the switching valve 16 is kept at a normal position without flowing a current.

Thus, the differential pressure control valve 15 is controlled so that the differential pressure Δp between the first and second control ports 23 and 24 is zero, and the switching valve 16 is connected to the stabilizer 1.
The rotary actuators 2f, 2r of f, 1r are kept in a blocked state, and therefore, the operations of these rotary actuators 2f, 2r are locked, and the stabilizers 1f, 1r perform their normal operations.

In addition, by keeping the switching valve 16 in the normal position, the hydraulic pump 12 of the hydraulic power source 14 is in the unloaded state, and at the same time, the energy saving effect is achieved.

On the other hand, when a lateral acceleration is generated in the vehicle body such as when turning, the lateral acceleration detector 19
Detects the magnitude of the lateral acceleration and inputs a control signal corresponding thereto to the controller 18.

The controller 18 outputs a switching signal to the electromagnetic solenoid 16a of the switching valve 16 in response to the input of the control signal to switch the switching valve 16, and opens the hydraulic circuit 11 to open the rotary actuator 2f in the stabilizers 1f, 1r. The ports 9a and 9b of the 2r are opened to the hydraulic pressure source 14.

On the other hand, at the same time, the controller 18 outputs a lateral acceleration signal (control current signal) corresponding to the magnitude of the control signal.
Is output to the electromagnetic solenoid 15a of the differential pressure control valve 15, and accordingly, the proportional control valve 15 performs the above-described control operation, and outputs the differential pressure corresponding to the magnitude of the lateral acceleration signal to the stabilizers 1f, 1r. Between the ports 9a and 9b of the rotary actuators 2f and 2r.

Thus, the rotary actuator 2
The f and 2r apply, through the stabilizers 1f and 1r, a roll moment in the opposite direction to the roll moment acting on the vehicle body due to the centrifugal force at that time, thereby effectively suppressing the roll generated on the vehicle body.

Thus, when the vehicle returns to a normal state such as straight traveling again, the lateral acceleration signal from the control device 17 disappears, and the differential pressure control valve 15 and the switching valve 16 are switched to the original switching positions. As described above, the stabilizers 1f and 1r perform normal operations, and the hydraulic power source 14 is also in the unload state.

In the above, if an abnormal situation occurs such that the reference current of the control device 17 becomes zero, the differential pressure control valve 15 operates to the maximum on one side and the maximum differential pressure is applied to the rotary actuators 2f and 2r. Take the position to apply pressure.

Therefore, if a roll moment acting in the same direction as the roll direction by the rotary actuators 2f and 2r acts on the vehicle body at this time, the vehicle body is greatly inclined in that direction due to the synergistic action of these two rolls. Can also cause

However, even in this case, since the switching valve 16 always assumes the normal position at the same time, the ports 9a and 9b of the rotary actuators 2f and 2r are blocked by the switching valve 16, and at least the stabilizers 1f and 1r are turned off. A normal operation is performed to suppress the roll of the vehicle body.

At the same time, the hydraulic pressure source 14
As a result, the unloaded state is maintained, and the energy saving and the fail-safe effect are achieved.

[0064]

As described above, according to the present invention, a roll generated on a vehicle body can be effectively suppressed while automatically controlling a variable hydraulic stabilizer by a simple hydraulic circuit and a control device. . In addition, in the normal state where the roll control is not performed, the hydraulic source is automatically kept in the unload state to save energy, and the hydraulic source is switched to the unload state even in the event of an abnormality in the control device. The rotary actuator of the stabilizer is locked while maintaining the same, whereby energy saving and a fail-safe effect can be achieved. Further, the differential pressure control between the two ports of the rotary actuator can be performed by using a differential pressure control valve having a set of an electromagnetic solenoid and a feedback chamber. Since the number of harnesses and the like can be reduced by half, manufacturing can be facilitated and cost can be reduced.

[0065]

[0066]

Further, in addition to the above, the form of the differential pressure control valve itself is reduced in size and the weight is reduced.
The same effect as that of the first aspect can be achieved by using a differential pressure control valve suitable for use as an in-vehicle device whose installation space and weight are restricted.

[Brief description of the drawings]

FIG. 1 is a schematic diagram systematically showing an embodiment of a roll control device according to the present invention.

FIG. 2 is a longitudinal sectional view showing an example of a rotary actuator used for a variable hydraulic stabilizer.

FIG. 3 is a longitudinal sectional view showing an example of a differential pressure control valve suitable for use in a control system of the present invention.

FIG. 4 is a graph showing a relationship between a control current to an electromagnetic solenoid of the differential pressure control valve and a control differential pressure.

[Explanation of symbols]

 1f, 1r Stabilizer 2f, 2r Rotary actuator 11 Hydraulic circuit 14 Hydraulic source 15 Differential pressure control valve 15a, 16a, 27 Electromagnetic solenoid 16 Switching valve 17 Control device 18, 28 Controller 19 Lateral acceleration detector 20 Valve housing 21 Supply port 22 Discharge Ports 23, 24 Control port 36 Control spool 37, 38 Back pressure chamber 40a, 40b Passage 42 Reaction force pin 43 Feedback chamber 44 Through hole 45 Spring

Continuation of the front page (56) References JP-A-5-310023 (JP, A) JP-A-63-180510 (JP, A) JP-A-61-24609 (JP, A) JP-A-2-296524 (JP) JP-A-60-169314 (JP, A) JP-A-4-191114 (JP, A) JP-A-64-101215 (JP, A) JP-A-63-263124 (JP, A) 60-29317 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60G 1/00-25/00

Claims (1)

(57) [Claims] 1. A variable hydraulic stabilizer which is divided into two parts by a torsion bar and connected by a rotary actuator, and a hydraulic source for operating the rotary actuator, and is provided in a hydraulic circuit connecting the hydraulic source and the rotary actuator. A switching valve that keeps the hydraulic pressure source in the unloaded state at the normal position with the differential pressure control valve and the rotary actuator on the stabilizer side in the blocked state is arranged in series, and switches with these differential pressure control valves using the lateral acceleration signal. In a roll control device for a vehicle provided with a control device for switching and controlling a valve, the differential pressure control valve has a valve housing having two supply ports, a supply port, a discharge port, and an output port; Separate back pressure chambers at both ends in housing and slidably insert And a feedback chamber formed in the control spool by applying a base end of a reaction force pin slidably inserted into one end of the control spool to the valve housing. A spring is provided between the end face on the reaction pin side and the valve housing with respect to both end faces, and a thrust is applied to the end face on the opposite end face to switch the control spool while cooperating with the spring. A solenoid is disposed, and among the two control ports, a control port that becomes a high pressure side when the thrust of the electromagnetic solenoid overcomes the spring and switches the control spool communicates with the feedback chamber, and a low pressure side. A roll control device for a vehicle, wherein the other control ports are respectively connected to the back pressure chambers.