JPH02141318A - Posture control device for vehicle body - Google Patents

Abstract

PURPOSE:To make it possible to smoothly and safely control posture by connecting in parallel a first control valve operatively associated with handle operation and a second control valve operatively associated with a control arm, between a vehicle height adjusting actuator supporting a control arm supporting a wheel and a fluid pressure source. CONSTITUTION:In a vehicle of which vehicle height is adjusted by inclination control of control arms 14 supporting respective wheels, by control units for front and rear wheels containing actuators A arranged on respective wheels, front and rear, right and left, pressure oil from the cylinder of a hydraulic front wheel steering mechanism C operated with a handle 43 is fed to respective control units. Second control valves 30 actuating to restore motion of the control arms 14 to neutral positions corresponding to inclination of the control arms 14 are provided on the respective control units. Further, a pair of right and left first control valves 51, 51a are provided on the rear wheel control units operatively associated with an actuator B connected to the front wheel steering mechanism C, and actuate to increase the vehicle height on the outside of turning route and decrease the vehicle height on the inside of turning route.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a vehicle body attitude control device that suppresses misappropriation of the vehicle body when traveling on oil roads.

[Conventional technology] The vehicle body moves forward and backward due to acceleration and deceleration of the vehicle, driving on oil roads, and changes in the road surface.
Lean from side to side. In order to suppress changes in the posture of the vehicle body as much as possible and maintain a stable horizontal posture,
As disclosed in Publication No. 9, there is a known vehicle that mechanically detects changes in vehicle height and directly drives a hydraulic control valve.
With this technology, the hydraulic actuator moves only in the direction of raising the vehicle height, and the action of lowering the vehicle height is left to the weight of the vehicle, so there is a problem in that the responsiveness to changes in vehicle height is poor.

Even if reciprocating hydraulic actuators, electromagnetic actuators, or motors are used, feedback control of the vehicle height of each wheel based on changes in vehicle height detected by a vehicle height sensor has a limited responsiveness, making it difficult for the vehicle to change lanes. , slalom, etc., and depending on the driving mode, changes in the vehicle's attitude may diverge, causing the vehicle to spin.

[Problems to be Solved by the Invention] The object of the present invention is to detect that the vehicle has entered the oil road driving state from a change in the turning angle of the steering wheel, to activate the 1lIIl valve, and to operate the control valve for feedback before the feedback control valve is activated. Another object of the present invention is to provide a highly stable vehicle attitude control device that operates a vehicle height adjustment actuator in a direction that should be subjected to feedback control to compensate for the response delay of the feedback valve.

[Means for Solving the Problems] In order to achieve the above object, the configuration of the present invention includes a seven-piece unit for adjusting vehicle height supported between a control arm supporting an axle and a vehicle body, and a fluid pressure source. In between, there is a first control valve that works in conjunction with the steering wheel operation via a damper to raise the vehicle height on the outside of the white bean paste and lower the vehicle height on the inside of the white bean paste, and a first control valve that works in conjunction with the control arm to change the vehicle height. It is connected in parallel with a second control valve that acts to cancel the flow.

[Function] When the vehicle is running, when the steering wheel 43 is turned, the actuator B that is linked to the front wheel steering mechanism C is driven, and the damper 6 is activated.
The first control valves 51.51a on the left and right sides are driven via the valves 0 and 60a, and the actuator A for adjusting the vehicle height of the wheels outside the oil passage is extended, increasing the vehicle height, while the wheels on the inside of the oil passage are extended. The actuator A for adjusting the vehicle and horse is shortened, and the vehicle height is lowered. While the vehicle is running, when the inclination of the control arm 14 changes due to changes in the road surface and movement of the vehicle body load, the second control valve 30 is driven and the inclination of the control arm 14 is controlled to return to the neutral position. .

Therefore, when the vehicle enters the oil path, the actuator A is driven by the first control valve 51.51a to prevent the vehicle body from sinking to the outside of the white bean paste. is driven by the second control valve 30 that responds to changes in the inclination of the control arm 14, thereby suppressing changes in vehicle height.

[Embodiments of the Invention] FIG. 3 is a schematic configuration diagram of a vehicle body attitude control device according to the present invention. Control arms 14 (
The inclination (Fig. 1) is controlled and the vehicle height is adjusted. A front wheel control unit and a rear wheel control unit are provided to separately control the front wheel actuator A and the rear wheel actuator A.

Pressure oil from the cylinder of the hydraulic front wheel steering mechanism C operated by the handle 43 is sent via pipes 68, 69 to the front wheel control unit and the rear wheel control unit, thereby driving the first control valve, A fluid pressure circuit extending from the hydraulic pump 36 to each actuator A via the pipe 37, the front wheel control unit, the rear wheel control unit, and the pipe 2a or 3a is controlled.

The front wheel control unit and the rear wheel control unit also have a second control valve 30 that operates to restore the tilt of the control arm 14 to the neutral position in response to the tilt of the control arm 14 that supports each wheel.
(FIG. 1), and the fluid pressure circuit of the actuator A is also controlled by the second control valve 30.

FIG. 1 is a hydraulic circuit diagram of a rear wheel control unit that controls actuator A of the left rear wheel. The front wheel control unit is also configured similarly to the rear wheel control unit, and the actuator A for the right rear wheel is also configured similarly to the actuator A for the left rear wheel. The rear wheel control unit includes an actuator B that is interlocked and connected to the front wheel steering mechanism C, a pair of left and right first control valves 51.51a that are driven by the actuator B, and the operation of the control arm 14 that supports the rear wheel 40. A pair of left and right second I control valves 30 (second right control valve 3
0 is not shown).

The hydraulic front wheel steering mechanism C is integrally equipped with a servo control valve 45 and an actuator. For example, when the steering wheel 43 is turned to the right, the valve body connected to the steering shaft 44 is activated, and the pressure oil of the hydraulic pump 42 is activated. passes through the servo control valve 45 to the cylinder 47
enters the end chamber 53 and pushes the piston 46 to the left. At the same time, oil in the end chamber 52 is returned to the oil tank 41 via the servo control valve 45. When the tie rod 59 is pushed to the left together with the piston 46, the knuckle arm 48 that supports the front wheel 50
is rotated clockwise around the support shaft 49, and the front wheel 50
is deflected to the right.

The servo control valve 45 is a four-bottom neutral position open type directional switching valve, and when the rotation of the handle 43 is stopped, the valve passage of the servo control valve 45 becomes a neutral state, and the piston 46 stops at its operating position. The front wheel 50 is held at a position corresponding to the turning angle of the handle 43.

The actuator B is driven in conjunction with the operation of the handle 43, specifically, in conjunction with the front wheel steering mechanism C. That is, since the end chambers 52 and 53 of the cylinder 47 are communicated with the end chambers 65 and 66 of the cylinder 63 through the pipes 68 and 69, the rod 67 is pushed to the left together with the piston 64. Both ends of the rod 67 are connected to the pistons of the null tampers 60, 60a by fitting the pistons into the cylinders,
Each spool 58 of the first control valve 51, 51a has a cylinder.
connected to.

The first control valve 51 on the left side is a four-bottom neutral position block type directional switching valve having a spool 58 mounted on a valve housing 56. The spool 58 is biased toward the neutral position by springs 57 on both ends. The first control valve 51a on the right side is also configured symmetrically with the first control valve 51.

As shown in FIG. 2, the first control valve 51 has a pair of left and right annular grooves 62a on the inner peripheral surface of the valve housing 56.

61atfi is provided, and the input boat 37b with which the pipe 37a communicates between the annular grooves 628.61a is connected to the annular grooves 61a,
An input boat 34b communicating with the pipe 34a is provided on the outside of each of the input ports 62a. The spool 58, which is biased toward the neutral position by a pair of left and right springs 57, is formed with an annular groove 54 communicating with the central input boat 37b and a pair of annular grooves 55 communicating with the input boats 34b on both sides at the neutral position. Ru. A pipe 62 connected to the annular groove 628 is connected to the end chamber 2 of the actuator A via the pipe 2a (FIG. 1), and a pipe 61 connected to the annular groove 618 is connected to the end chamber 2 of the actuator A.
are respectively communicated with the end chambers 3 of the actuator A via pipes 3a.

As shown in FIG. 1, an actuator A that adjusts the vehicle height of the left rear wheel 40 is incorporated into a suspension mechanism for the rear wheel 40. As shown in FIG.

A control arm (lower arm) 14 is tiltably supported on the vehicle body 1 by a longitudinal support shaft 15, and a knuckle 10 is connected to the tip of the control arm (lower arm) via a ball joint 12. A rear wheel 40 is rotatably supported by the knuckle 10. A shock absorber 8 is connected between the control arm 14 and the bottom of the vehicle body 1, and a suspension spring 18 and an actuator A are arranged in series. In the actuator A, a piston 5 is fitted inside a cylinder 4 connected to the bottom of the vehicle body 1, and an end chamber 2.3 is defined. A rod 6 connected to the piston 5 is projected downward. A suspension spring 18 is interposed between the spring seat 7 connected to the rod 6 and the spring seat of the control arm 14.

The upper arm is attached to the side wall of the vehicle body 1 by a support shaft 21.
19 is tiltably supported, and the tip of the upper arm 19 is connected to the ball joint 9.
is connected to the upper end of the knuckle 10, thereby forming a known double Witschbon type suspension mechanism. However, the present invention is not limited to this suspension mechanism, but is also applicable to strut type suspension mechanisms.

Like the first control valve 51, the second control valve 30 is a four-bottom neutral position block type directional control valve, and a valve housing 31 connected to the vehicle body 1 is provided with a spool 32 and a pair of springs 33.
A rod protruding from the spool 32 is connected to the link 26 by a pin 27. The other end of the link 26 is connected to one arm of the bell crank 23 by a pin 25.

The bell crank 23 is rotatably supported on the vehicle body 1 by a support shaft 24, and the other arm is connected to the link 17 by a pin 20. The lower end of the link 17 is connected to the control arm 1 by a ball joint 16.
It is connected to the middle part of 4.

Output ports connected to a pair of annular grooves in the valve housing 31 of the second control valve 30 communicate with the end chambers 2 and 3 of the actuator A via pipes 28, 2a and 29.degree. 3a, respectively.

An input port at the center of the valve housing 31 is communicated with a discharge port of a hydraulic pump 36 via a pipe 37, and the valve housing 31
The input boats on both sides of the tank are connected to an oil tank 35 via a pipe 34.

A hydraulic pressure/flow control valve 38 and a pressure accumulator 39 are connected in the middle of the pipe 37 .

Next, the operation of the vehicle body attitude control device according to the present invention will be explained. When the vehicle approaches the oil path, if the steering wheel 43 is turned to the right, for example, the actuator B is activated as described above.
While the pressure oil of the hydraulic pump 42 is supplied to the end chamber 66 of
Oil in the end chamber 65 is returned to the oil tank 41. therefore,
The rod 67 moves to the left together with the piston 64, and the spool 58 is pushed to the left via the damper 60 against the force of the spring 57. The pressure oil of the hydraulic pump 36 is connected to the pipe 37° 37a.
1 is supplied to the upper end chamber 2 of the actuator A via the first control valve 51 and the pipe 62.2a.

The oil in the lower end chamber 3 is supplied to the pipes 3a, 61, and the first 1lIi11.
It is returned to the oil tank 35 via valve 51 and pipe 348.34. In this way, the rod 6 is extended by the piston 5 of the actuator A, the control arm 14 is tilted downward about the support shaft 15, and the vehicle height of the left rear wheel 40 is increased.

On the other hand, in the first control valve 51a on the right side, the pipe 37a is connected to the pipe 61.
Although not shown, pressurized oil is supplied to the lower end chamber 3 of the cutter A of the right wheel, lowering the vehicle.

In this way, at the same time as the steering wheel 43 is turned to the right, the vehicle height of the outer wheels of the oil passage is increased and the vehicle height of the inner wheels is lowered, so that tilting of the vehicle body 1 to the left due to centrifugal force is suppressed. Eventually, due to the action of the dampers 60 and 60a, the first control valve 51
．． 518 returns to the neutral position and actuator A is held in the adjusted position.

When the vehicle enters the oil road driving state, the left front wheel 50 and rear wheel 4
0 sinks in a bumpy manner), and the front and rear wheels on the right side rise up in a rebound manner), at which point the second control valve 30 operates.

In other words, when the axle load on the left wheel increases due to centrifugal force,
The suspension spring 18 is compressed and the car on the left becomes lower. The control arm 14 tilts upward about the support shaft 15, the bell crank 23 rotates clockwise in FIG. 1 about the support shaft 24, and the spool 32 of the second control valve 30 moves to the left. . Due to the leftward movement of the spool 32, 9!37 moves to the pipe 2.
8 and tube 34 is in communication with tube 29 . Therefore, the pressure oil from the hydraulic pump 36 is i! 37, second control valve 30,
The oil in the lower end chamber 3 is supplied to the upper end chamber 2 of the actuator A via the tube 28. It is returned to the oil tank 35 via the pipe 34. In this way, the piston 5 protrudes downward and the 1IilJIIl arm 14 is pushed back to the position shown in the figure, so that the left side of the vehicle body sinks.

When the control arm 14 is pushed back to the illustrated position by the actuator A, the spool 32 is returned to the illustrated neutral position by the operation of the bell crank 23, the operation of the actuator A is stopped at that position, and the vehicle height is adjusted to that height. It is maintained. Control l1II as the road surface changes and the axle load moves! When the tilt of the control arm 14 changes, the second control valve 30 operates continuously to cancel the change, and the actuator 8 operates to cancel the change in the tilt of the control arm 14 from the reference position.

Conversely, when the axle load on the right wheel decreases, control 1'1i
l14 tilts downward, the second control valve 30 operates in the opposite direction,
Pressure fluid from the hydraulic pump 36 is sent to the lower end chamber 3 of the 7-cut unit A, and the piston 5 moves upward, thereby canceling out the change in vehicle height.

Although the case of the left and right rear wheels 40 has been described above, the front wheel control unit similarly operates in the case of the left and right front wheels 50.

[Effects of the Invention] As described above, the present invention provides a system in which a vehicle height adjustment actuator supported between a control arm supporting an axle and a vehicle body and a fluid pressure source are interlocked with handle operation via a damper. A first control valve that works to raise the vehicle height on the outside of the oil passage and lower the vehicle height on the inside of the oil passage, and a second control valve that works in conjunction with the III control arm to cancel out changes in vehicle height. Since the valves are connected in parallel, when the vehicle is traveling on a curved road, the vehicle height of the outer wheels of the oil passage is raised and the vehicle height of the inner wheels is lowered by the action of the first control valve at the same time as the steering wheel is operated. When the tilting of the vehicle body to the outside of the oil path due to the force is suppressed and the vehicle enters the state of traveling on the oil path, the second control valve operates and the control arm is driven by the actuator to cancel out the i^ change. The vehicle body is kept almost horizontal.

As mentioned above, when the vehicle is running on oil roads or slalom, the actuator operates quickly to prevent the vehicle from stealing and keep the vehicle level, resulting in smooth and highly safe posture control without causing any discomfort to the driver. is obtained.

[Brief explanation of the drawing]

Fig. 1 is a hydraulic circuit diagram for operating the left rear wheel actuator of the vehicle body attitude control system according to the present invention;
The figure is a plan sectional view of the first control valve in the attitude control device, and FIG. 3 is a schematic configuration diagram of the entire attitude control device. A: Actuator C: Front wheel steering mechanism and vehicle body 2,
3 = End chamber 4 Niji cylinder 5: Piston 14: Control arm
15: Support shaft 18: Suspension spring 30: Second control valve 3
2 Nisbourg 36: Hydraulic pump 40: Rear wheel 50:
Front wheel 51.51a: First control valve 60.60a: Damper patent applicant Isuzu Motors Co., Ltd.

Claims (1)

[Claims] An actuator for adjusting the vehicle height supported between the control arm supporting the axle and the vehicle body and a fluid pressure source are connected to the steering wheel operation via a damper to raise the vehicle height on the outside of the oil passage. A vehicle body characterized in that a first control valve that works to lower the vehicle height on the road side and a second control valve that works in conjunction with a control arm to cancel changes in vehicle height are connected in parallel. Attitude control device.