JPH0867126A - Stabilizer device for vehicle - Google Patents

Abstract

PURPOSE: To execute drive control on a stabilizer bar by means of air by providing air springs at the upper and lower parts of a stabilizer drive member, and letting the suction and exhaust of air be carried out based on the difference in pressure between a target value operated based on a detected value such as the inner pressure of an air spring and the like and an actually detected value. CONSTITUTION: One end of a stabilizer bar 18 and the other end are disposed at an axle 16, and at a drive member 26 disposed at an air cylinder 14 respectively, and a first and second air spring are interposed between a drive member 26 and a body 10, and between the drive member and a bracket 40 fixed onto the body 10 respectively. Respective signals for the pressure of the first and second air springs, sensors 92 and 94, a steering angle, vehicle speeds, and lateral acceleration are inputted to a controller to compute target pressure for both the air springs 28 and 3O, and each pressure command value computed based on a initial pressure value, and each detected pressure value are compared with the aforesaid target pressure, so that a drive command is thereby outputted. Based on the aforesaid command, a first and a second suction and exhaust valve 48 and 58; 52 and 62 are driven, so that both the sir springs 28 and 30 are thereby controlled. Therefore, the drive control of the stabilizer bar 18 can be executed by means of air pressure, and the device can thereby be made light in weight.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle stabilizer device, and more particularly to a stabilizer device suitable for use in vehicles such as trucks and buses.

[0002]

2. Description of the Related Art Conventionally, in order to suppress rolling of a vehicle body to improve running stability and the like, a stabilizer device has been widely used as a means for supplementing roll rigidity of a suspension spring with a spring steel bar, that is, a stabilizer bar. As a device for controlling the position of the stabilizer bar according to the traveling state, a device utilizing a hydraulic actuator has been proposed (for example, Japanese Utility Model Publication No. 63-104105 and Japanese Utility Model Publication No. 63-1).
55808, etc.).

[0003]

However, in the case where the hydraulic actuator is used to drive the stabilizer bar, a hydraulic power source device is required, and in order to construct a high pressure hydraulic system, the equipment is Since it is necessary to increase the strength, it is unavoidable to increase the wall thickness of the members constituting the hydraulic system such as the cylinder, and the weight increases. Further, when the stabilizer bar is driven, the ground clearance at the end of the stabilizer bar on the actuator side is lowered, and the running performance is poor.

It is an object of the present invention to provide a lightweight stabilizer device for a vehicle which can control the drive of the stabilizer bar by using the pressure of air and has excellent running performance.

[0005]

In order to achieve the above object, the invention of claim 1 is such that a stabilizer bar rotatably fixed to an axle and one end of the stabilizer bar rotatably fixed to a vehicle body. A supporting member for supporting, a driving member rotatably connected to the other end of the stabilizer bar, a first air spring arranged on the upper side of the driving member, and a second air arranged on the lower side of the driving member. Second fixed to the spring and body
A bracket that supports the air spring, an air reservoir that stores the air, a first air supply valve that controls the air supply from the air reservoir to the first air spring, and a first air valve that controls the exhaust of the air in the first air spring. A first exhaust valve, a second air supply valve that controls the supply of air from the air reservoir to the second air spring, a second exhaust valve that controls the exhaust of air in the second air spring, and a first air spring Pressure sensor for detecting the pressure in the second air spring, a second pressure sensor for detecting the pressure in the second air spring, a steering angle detecting means for detecting the steering angle of the vehicle, a vehicle speed detecting means for detecting the vehicle speed, and a steering wheel. The lateral acceleration detection means for detecting lateral acceleration based on the detection outputs of the angle detection means and the vehicle speed detection means, and the pressure target values of the first and second air springs are calculated based on the detection outputs of the lateral acceleration detection means. Pressure target value calculation means and pressure Pressure command value calculation means for calculating pressure command values for the first and second air springs from the calculated value of the standard value calculation means and the initial pressure values for the first and second air springs, and calculation by the pressure command value calculation means A first comparing means for comparing the value with the detection value of the first pressure sensor; and a second comparing means for comparing the calculated value of the pressure command value calculating means with the detected value of the second pressure sensor.
The comparing means, the first drive commanding means for instructing the driving of the first air supply valve and the first exhaust valve according to the comparison result of the first comparing means, and the second air supply according to the comparison result of the second comparing means. It is a stabilizer device of a vehicle provided with a valve and a 2nd drive command means which commands drive of the 2nd exhaust valve.

According to a second aspect of the invention, the other end side of the stabilizer bar is twisted toward the vehicle body side and arranged at a higher position than the one end side of the stabilizer bar, and the invention according to the third aspect is the drive member, The first and second air springs are arranged so that the line connecting the respective central portions is vertical with respect to the other end side of the stabilizer bar.

[0007]

According to the present invention, when the lateral acceleration is detected based on the steering angle and the vehicle speed of the vehicle, the target pressure value of each air spring is calculated based on the lateral acceleration. The pressure command value for each air spring is calculated from the target pressure value and the initial pressure value. Then, the pressure command value and the detection value of each pressure sensor are compared, and the drive of each air supply valve and exhaust valve is controlled according to the comparison result.

That is, when the air supply valve is opened, the pressure of the corresponding air spring is controlled to be high, and when the exhaust valve is opened, the pressure of the corresponding air spring is controlled to be low. Further, since the stabilizer server is driven by using the air from the air reservoir, it is not necessary to newly provide a hydraulic pressure source device, and the roll suppression control can be performed while reducing the weight.

According to the second aspect of the present invention, the ground height of the drive end of the stabilizer bar is increased and the running performance is improved.

[0010]

An embodiment of the present invention will be described below with reference to the drawings. 1 is a view showing a state in which a stabilizer device according to an embodiment of the invention of claims 1 and 2 is fixed to a vehicle body, and FIG. 2 is a top view showing a state in which the stabilizer device is fixed to the vehicle body. . Although this stabilizer device is provided on both the front and rear sides, it may be provided on only one side.

1 and 2, a suspension 12 composed of a leaf spring, a coil spring, an air spring or the like is fixed to a vehicle body 10 and an air cylinder 14 is provided.
Has been fixed. One end of the suspension 12 is connected to an axle (axle) 16, and a stabilizer bar 18 is rotatably fixed to the axle 16 by a pair of bearings 20. One end of the stabilizer bar 18 has a bearing 22
Is rotatably connected to the vehicle body 10. One end of the bearing 22 is connected to the vehicle body 10 via a rod 24. That is, bearing 2
2, the rod 24 is configured as a support member. On the other hand, the other end side of the stabilizer bar 18 is twisted toward the vehicle body side by an initial twist angle φ with respect to one end side of the stabilizer bar 18 and is arranged at a high position. The other end of the stabilizer bar 18 is rotatably connected to the drive member 26.

The drive member 26 is arranged in a substantially central portion of the air cylinder 14 and is formed in a substantially box shape. The first air spring 28 is arranged on the upper side of the drive member 26, and the second air spring 30 is arranged on the lower side. The first air spring 28 is a first bellows portion 3 that constitutes an expandable air chamber.
2 and the first piston part 3 for expanding and contracting the first blow part 32
4 and is mounted between the drive member 26 and the vehicle body 10. The second air spring 30 is composed of a second bellows portion 36 that constitutes an expandable air chamber and a second piston portion 38 that expands and contracts the second bellows portion 36, and is mounted between the drive member 26 and the bracket 40. ing. The bracket 40 is formed in a substantially U shape, and the upper side thereof is the vehicle body 10
It is fixed to.

The first bellows portion 32 is connected to an air reservoir 46 which stores air via a pipe line 42 and a pipe 44, and a first air supply valve 48 is inserted in the middle of the pipe 44. A first exhaust valve 52 is connected to the pipe 50 branched from the pipe 44. On the other hand, the second bellows portion 36 is connected to the air reservoir 46 via the conduit 54 and the pipe 56. A second air supply valve 58 is inserted in the middle of the pipe 56, and a second exhaust valve 62 is connected to the pipe 60 branched from the pipe 56. A controller 64 as shown in FIG. 3 is provided to control the drive of each air supply valve and exhaust valve.

The controller 64 has a plurality of input means 66.
˜74, a control means 76, and a plurality of output means 78 to 84. A steering angle detecting means 86, which is provided on the steering wheel and detects the steering angle of the vehicle, is connected to the input means 66. Input means 68
A vehicle speed detecting means 88 provided in the transmission for detecting the vehicle speed is connected to the. The input means 70 has a lateral acceleration detecting means 9 for detecting a lateral acceleration acting on the vehicle body.
0 is connected. The input means 72 has a first air spring 2
A first pressure sensor 92 provided on the pipe 44 for detecting the pressure in the valve 8 is connected. A second pressure sensor 94 provided on the pipe 56 for detecting the pressure in the second air spring 30 is connected to the input means 74. Control means 76
Calculates the pressure target value for each air spring 28, 30 based on the signals from each input means 66-74, and calculates the pressure command value for each air spring 28, 30 from the pressure target value and the initial pressure value. The calculated value and each pressure sensor 9
The detection values of Nos. 2 and 94 are compared with each other, and a drive command corresponding to each comparison result is output via the output means 78 to 84. That is, the controller 64 constitutes pressure target value calculation means, pressure command value calculation means, first and second comparison means, and first and second drive command means.

Next, the operation of this embodiment will be described with reference to the flow charts of FIGS. First, the detection outputs of the steering angle detection means 86 and the vehicle speed detection means 88 are read (steps S1 and S2), and the lateral acceleration Y1 is calculated (step S).
3). This calculation is performed according to the equation shown in step S3. Here, N is a steering gear ratio, L is a wheel base, and K is a stability factor. Then, the lateral acceleration Y2 detected by the lateral acceleration detecting means 90 is read (step S4). Next, it is determined whether the absolute value of the deviation between the lateral accelerations Y1 and Y2 is smaller than the set value α (step S5). When the determination is YES, Y1 is used as the lateral acceleration (step S6), and when the determination is NO, Y2 is used as the lateral acceleration (step S7).

Then, the process proceeds to step S8, and step S8
A process for calculating the target pressure values for the front side air spring and the rear side air spring is performed according to the equation shown below. Here, Lf is the distance between the front axis and the center of gravity, Lr is the distance between the rear axis and the center of gravity, Tf is the front star screw pan, Tr is the rear star screw pan, Asf is the area of the front air spring, Asr is the area of the rear air spring, m is the mass on the spring, and h is the roll height.

Then, the process proceeds to step S9 and step S8.
A pressure command value for each air spring is calculated according to the formula of step S9 from the target pressure value calculated in step S1 and the initial pressure value of each air spring. Here, P _f1REQ and P _f2REQ are pressure command values of the upper and lower air springs on the front side, and P _r1REQ and P _f1REQ
r2REQ is the pressure command value for the upper and lower air springs on the rear side.
Each pressure initial value is set to Pf10 = Pf20 (front side pressure initial value) and Pr10 = Pr20 (rear side pressure initial value). Further, α indicates a roll control coefficient on the front side, and β indicates a roll control coefficient on the rear side. If these coefficients are made high, the pressure becomes large, and if they are made small, the pressure becomes low.

After the pressure command values for the first and second air springs on the front side and the pressure command values for the first and second air springs on the rear side are calculated in step S9, the first pressure sensor 92, The detection value of the second pressure sensor 94 is fetched (step S10). That is, the internal pressures of the first and second air springs on the front side and the internal pressures of the first and second air springs on the rear side are read respectively. And step S
The pressure command value calculated in 9 is compared with the current internal pressure of the air spring read in step S10, and the drive of the air supply valve and the exhaust valve is controlled according to the comparison result (step S11). This processing is a subroutine processing, and control as shown in FIG. 5 is performed.

That is, the deviation between the pressure command value for each air spring calculated in step S9 and the internal pressure of each air spring read in step 10 is compared (step S2).
0). At this time, when the pressure command value is larger than the detected value, the first or second air supply valve is opened (step S2
1), closing the first or second exhaust valve (step S
22). When the pressure command value for each air spring is equal to the measured value, the first or second air supply valve is closed (step S23), and the first or second exhaust valve is closed (step S24). On the other hand, when the pressure command value for each air spring is smaller than the detected value, the first or second air supply valve is closed (step S25) and the first or second exhaust valve is opened (step S26).

The control in steps S20 to S26 is sequentially performed for each of the front and rear air springs, and the drive of the air supply valve and the exhaust valve is controlled in accordance with the deviation between the pressure command value and the detected value. It will be.

When the control according to FIGS. 4 and 5 is performed,
As shown in FIG. 6, the anti-roll moment generated by the stabilizer can be increased, and the roll angle depending on the steering angle and the lateral acceleration can be reduced.

As described above, according to this embodiment, since the drive of the stabilizer bar 18 is controlled by using the air source, it is not necessary to newly use a hydraulic pressure source device, and an increase in weight can be suppressed. it can.

Further, in this embodiment, the roll angle can be greatly reduced as compared with the fixed stabilizer device, and the maneuverability and stability can be improved. Further, since the hydraulic power source device is not used, the horsepower loss of the engine can be reduced and the deterioration of fuel consumption can be suppressed. Further, since the air spring is used as the stabilizer drive unit, it is possible to enhance the absorbability of high frequency vibration and contribute to the improvement of the riding comfort.

Further, according to this embodiment, since the initial twist angle is provided at the end of the stabilizer bar 18 to increase the ground clearance, the running performance in the case where there is a road surface protrusion or the like can be secured. When the air cylinder 14 is fixed to the vehicle body 10, as shown in FIG. 7, the line connecting the centers of the drive member 26, the first air spring 28, and the second air spring 30 is based on the other end side of the stabilizer bar 18. Can also be arranged so as to be vertical (claim 3).

In this case, for the stabilizer bar 18,
Since the first air spring 28 and the second air spring 30 are vertical, the efficiency is higher than that in the above-described embodiment in which the angles are angled.

[0026]

As described above, according to the inventions of claims 1 and 3, since air is used as a pressure source and the drive of the stabilizer bar is controlled by the pressure of the air, it is possible to contribute to weight reduction. .

According to the second aspect of the present invention, roll suppression control excellent in running performance can be realized.

[Brief description of drawings]

FIG. 1 is a main part configuration diagram of a stabilizer device showing an embodiment of the inventions of claims 1 and 2. FIG.

FIG. 2 is a top view showing a state in which the stabilizer device of FIG. 1 is fixed to a vehicle body.

FIG. 3 is a block configuration diagram of the stabilizer device in FIG. 1.

FIG. 4 is a flowchart for explaining the operation of the controller in the stabilizer device in FIG.

5 is a flowchart for explaining a process in a subroutine of the controller shown in FIG.

6A and 6B are views for explaining the action and effect of the stabilizer device according to the embodiment of FIG.

FIG. 7 is a side view showing another embodiment of the air cylinder according to the embodiment of the invention of claim 3;

[Explanation of symbols]

 10 Vehicle Body 12 Suspension 14 Air Cylinder 16 Axle 18 Stabilizer Bar 26 Drive Member 28 First Air Spring 30 Second Air Spring 46 Air Reservoir 48 First Air Supply Valve 52 First Exhaust Valve 58 Second Air Supply Valve 62 Second Exhaust Valve 64 controller

Claims (3)

[Claims] 1. A stabilizer bar rotatably fixed to an axle, a support member fixed to a vehicle body to rotatably support one end of the stabilizer bar, and rotatably connected to the other end of the stabilizer bar. A drive member, a first air spring arranged on the upper side of the drive member, a second air spring arranged on the lower side of the drive member, and a bracket fixed to the vehicle body to support the second air spring, An air reservoir for storing air, a first air supply valve for controlling air supply from the air reservoir to the first air spring, a first exhaust valve for controlling exhaust of air in the first air spring, and an air reservoir for Two
A second air supply valve for controlling air supply to the air spring;
A second exhaust valve for controlling the exhaust of air in the second air spring, a first pressure sensor for detecting the pressure in the first air spring, and a second pressure sensor for detecting the pressure in the second air spring, Steering angle detection means for detecting the steering angle of the vehicle, vehicle speed detection means for detecting the vehicle speed, lateral acceleration detection means for detecting the lateral acceleration based on the detection outputs of the steering angle detection means and the vehicle speed detection means, and the lateral acceleration A first and a second based on the detection output of the detection means
Pressure target value calculating means for respectively calculating the pressure target value of the air spring, the calculated value of the pressure target value calculating means, and the first and second
The pressure command value calculation means for calculating the pressure command values of the first and second air springs from the initial pressure value for the air spring and the calculated value of the pressure command value calculation means and the detection value of the first pressure sensor are compared. The first comparing means, the second comparing means for comparing the calculated value of the pressure command value calculating means with the detected value of the second pressure sensor, and the first air supply valve and the first comparing valve according to the comparison result of the first comparing means. Vehicle provided with first drive command means for commanding drive of the exhaust valve, and second drive command means for commanding drive of the second air supply valve and the second exhaust valve according to the comparison result of the second comparing means. Stabilizer device. 2. The stabilizer device for a vehicle according to claim 1, wherein the other end side of the stabilizer bar is arranged at a higher position by being twisted toward the vehicle body side than the one end side of the stabilizer bar. 3. The vehicle according to claim 1, wherein the drive member and the first and second air springs are arranged such that a line connecting the respective central portions is vertical with respect to the other end side of the stabilizer bar. Stabilizer device.