JPS6255210A - Wheel suspension device or vehicle - Google Patents

Abstract

PURPOSE:To enhance the stability of a vehicle incorporating a suspension device whose damping force and spring constant is variable, by comparing the product of detection signals delivered respectively from an oscillation type angular speed detector and a vehicle speed detector with a set value, and by controlling the damping force and the spring constant in accordance with the result of the comparison. CONSTITUTION:A multiplier circuit 10 in a processor 3 receives a yaw angular speed signal 1 from an oscillation type angular speed detector and a vehicle speed signal 2 from a vehicle speed detector, and multiplies the thus received signals together, delivering the thus obtained value as a lateral acceleration to a comparator 12. The comparator 12 compares the thus delivered lateral acceleration with a set value 11, and if it is higher than the set value, energizes a drive circuit 13 which therefore, drives a damping force change-over actuator 5 to increase the damping force of a shock absorber. With this arrangement, it is possible to enhance the stability of the vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The damping force of the shock absorber of the present invention is controlled to improve the stability of a vehicle when turning. So-called anti-roll lt
Regarding control.

[Prior art, J-near and its problems] Conventionally, the steering angle has been detected by a steering sensor installed in the middle of the steering shaft for roll control, but the steering sensor has the following problems. be. (1) Since the disc is press-fitted and fixed to the steering shaft, the steering shaft must be modified, which increases the cost. (2) Since the neutral point of the steering is unknown, it is necessary to perform sensor correction without interrupting driving.

[Means for solving the problem and effects of the invention]

The present invention has been made in view of the above points, and therefore uses a vibrating angular velocity detector to detect rolls.

This detector consists of two pairs of piezoelectric link vibration elements and can obtain a signal proportional to angular velocity. The yaw angular velocity is detected by setting the measurement axis of the detector in the vertical direction of the vehicle. This detects vehicle turns and performs anti-roll control.

Here, the amount of roll of the vehicle, that is, the roll angle φ is expressed by the following equation.

φ−mshφ・■・ψ／φ However, ms + sprung mass, hφ: roll arm, kφ
: Roll stiffness, V: Vehicle speed, ψ: Yaw angular velocity Here, ms, hφ, and kφ are values specific to the vehicle, so the amount of roll is a function of the product of vehicle speed and 9-angular velocity. Therefore, it is controlled by the magnitude of the set value of the product of vehicle speed and yaw angular velocity.

Since this detector directly detects the vehicle's yaw angular velocity, there is no need to attach it to a moving part like a steering sensor, and the mounting location within the vehicle interior or trunk room can be freely selected. Furthermore, since no angular velocity occurs unless the car turns, there is no need for center correction.

〔Example〕

FIG. 1 is a schematic diagram showing the entire structure of the present invention.

1 is a vibration type angular velocity detector that outputs a signal corresponding to the yaw angular velocity of the vehicle; 2 is a vehicle speed detector that outputs a signal corresponding to the traveling speed of the vehicle; 3 is a device to which the signal is input to switch the damping force of the shock absorber 4; This figure shows the basic configuration of a processing device that outputs a drive signal to an actuator 5 that performs a process, in which a detection unit 7 and a drive unit 6 made of a piezoelectric vibration element are connected at an angle of 90° to each other, and the other end is fixed to a substrate 8. was done 2
Consists of a pair of cantilever beams.

When the drive section 6 is vibrated, the detection section 7 resonates in an arc in its plan view. When an angular velocity Ω exists around the detection axis, Coriolis acts perpendicularly to the detection section, bending the detection section and generating a signal. The magnitude of the signal is proportional to the angle and the phase depends on the direction of rotation.

9 is a case in which the above-mentioned angular velocity detection section is built-in. The case 9 is mounted inside the vehicle, trunk room, etc. using bolts, double-sided tape, etc. so that the detection axis is in the same direction as the vertical direction, and detects the yaw angular velocity caused by turning of the vehicle.

FIG. 3 is a control block diagram according to the present invention.

The outputs of the yaw angular velocity signal and the vehicle speed signal are multiplied by a multiplier circuit 10 and detected as a lateral acceleration that increases as the yaw angular velocity and vehicle speed increase. The output of this multiplier circuit 10 is compared with a predetermined set value 11 of a comparator 12, and when the output exceeds a predetermined value, the comparator 12 outputs a command signal, and the drive circuit 13 drives the damping force switching actuator to shock the driver. Control the damping force of the absorber to a high level.

Note that not only the damping force but also the spring constant or both the damping force and the spring constant may be controlled.

Further, the set value may be set to two or more types depending on the vehicle speed.

[Brief explanation of the drawing]

The accompanying drawings show embodiments of the present invention; FIG. 1 is an overall configuration diagram, FIG. 2 is a basic configuration diagram of a vibration type angular velocity detector, and FIG. 3 is a block diagram of a control system. 1... Vibration type angular velocity detector, 2... Vehicle speed detector, 3
...processing device, 4...shock absorber, 5...
・Actuator, 10... Multiplier circuit, 12... Comparator.

Claims (1)

[Claims] A vibration-type angular velocity detector that outputs a signal according to the yaw angular velocity of the vehicle in a vehicle wheel suspension system equipped with a shock absorber capable of changing at least one of the damping force and the spring constant. and a vehicle speed detector for detecting the speed of the vehicle; and means for controlling at least one of the damping force or the spring constant of the shock absorbing device by comparing a multiplication value of the outputs of the two detectors and a set value. Suspension system.