Abstract: A control system for controlling the adjustable damping rate of a suspension in a vehicle dependent on a road condition. The control system includes a detector for detecting a vibration acceleration of the vehicle, and a control means for controlling the suspension in response to information on the vibration acceleration from the first detector. The control system can automatically control the suspension quickly and reliably.

Abstract: An antilock brake system with separate front- and rear-wheel safety means, in which front-wheel antilock control means and rear-wheel antilock control means are made so operative independently of each other that, when the front-wheel antilock control means for a front wheel generally having a larger proportion of the brake force distributed is troubled in its brake force suppressing state, front-wheel saftey means makes the function of the front-wheel antilock control means wholly ineffective to ensure the brake force to the front wheel whereas, when the rear-wheel antilock control means for a rear wheel generally having a smaller proportion of the brake force distributed is troubled in a state having lost its brake force suppressing function, rear-wheel safety means operates to effect that the brake force to the rear wheel is always stronger than that to the front-wheel thereby to maintain the steering stability of the wheeled vehicle.

Abstract: A method of preventing wheels of a vehicle from skidding, including the steps of detecting the peripheral speed of a wheel and picking it up as a wheel-speed signal, detecting the vehicle speed and setting a reference wheel-speed signal based on the detected vehicle speed, deriving a wheel-acceleration signal from said wheel-speed signal, and setting a reference wheel-deceleration signal for comparison with said wheel-acceleration signal. During braking operation, the brake torque applied to the wheel is controlled such that it is maintained constant to prevent the further increase thereof when the level of the wheel-accleration signal decreases below the level of said wheel-deceleration signal under the condition that the level of said wheel-speed signal is higher than that of said reference wheel-speed signal.

Abstract: A method and apparatus for controlling an anti-skid brake in a vehicle, in which an estimated vehicle speed signal is obtained by selecting the higher value signal from wheel speed signals of the front and rear wheels at the left and right side and anti-skid brake devices for the front and rear wheels are independently controlled by independent signals. In this way, the anti-skid brake control can always be performed assuredly while preventing locking of the wheels on slippery roads while also preventing unnecessary anti-skid braking operations at the time of sharp turning. In a modified method and apparatus, control of the anti-skid brake of the rear wheel on the left or right side is effected according to vehicle speed estimated from the speed of a front wheel on the right or left side, whereby gradual locking of the wheels at the time of braking on a slippery road is prevented, and the anti-skid brake control can always be accomplished assuredly and excellent braking effects can always be obtained.

Abstract: A control circuit for a vehicle levelling system including a detecting device for detecting a change in vehicle height with respect to a predetermined reference vehicle-height position and generating a directional signal and an adjustment-on or -off command signal. A control device is provided for controlling the operation of a mechanical system according to the signals, and a holding device is provided for holding the adjustment-off signal for a certain period of time even when the command signal has changed from the adjustment-off signal to the adjustment-on signal. In case a plurality of reference vehicle-height positions are provided, in order that the switching between the reference positions can be performed smoothly, there is provided a circuit for interrupting the function of the adjustment-off signal holding circuit temporarily according to the switching operation.

Abstract: A control circuit for a vehicle level adjusting apparatus which avoids performing vehicle level adjustment in response to momentary changes in the vehicle level during driving of the vehicle, and at the same time provides a prompt vehicle level adjustment in response to essential or substantial changes in the vehicle level during a halt or rest state. The control circuit includes a first circuit which receives at least one first signal based on a comparison between a reference vehicle level range and an actual vehicle level to make a judgment as to the necessity of an adjustment of the vehicle level and issues a second signal having a first signal status when the adjustment is judged to be necessary and a second signal status when the adjustment is judged to be unnecessary.

Abstract: An antiskid brake controlling method and apparatus comprising: comparing by a first comparator and during braking of a vehicle, a wheel speed signal V.sub.w representative of the peripheral speed of a wheel of the vehicle with a first reference wheel speed signal V.sub.R 1 less than a vehicle speed signal V.sub.E and with a second reference wheel speed signal V.sub.R 2 which is less than the first reference wheel speed signal V.sub.R 1; comparing by a second comparator a wheel acceleration signal V.sub.w representative of the peripheral acceleration of the wheel with a first reference wheel acceleration signal V.sub.wl representing a predetermined positive peripheral acceleration of the wheel, a second reference wheel acceleration signal V.sub.w2 greater than the first reference wheel acceleration signal and a reference wheel deceleration signal -V.sub.w3 representative of a predetermined negative peripheral acceleration of the wheel.

Abstract: A control circuit for a vehicle leveling system which operates to restore the vehicle height to be within a reference vehicle height range. The control circuit comprises a first detecting device which detects the direction of change in the vehicle height, a second detecting device which determines the necessity of levelling operation, a logic circuit which properly controls the leveling operation in response to outputs of the first and second detecting devices, and a holding circuit which increases the duration of an OFF signal so as to render the pneumatic system of the vehicle to be inoperative, for a predetermined length of time. The control circuit effects adjustment in height in response to those changes in vehicle height which inherently require adjustment and avoids any adjustment in response to those changes in vehicle height which naturally occur instantaneously under normal driving conditions.

Abstract: A control and compensation device in an anti-skid control system in which wheel speed detectors detect peripheral speeds of wheels to produce wheel speed signals. A main control circuit receives wheel speed signals, and an electromagnetic actuator is provided for actuating the anti-skid control device. A control and compensation circuit is arranged so that when the wheel speed signal indicates the locked state of wheels continuously more than a predetermined period of time, the electromagnetic actuator is immediately placed in an energized state only for a predetermined time to produce an output signal for releasing the braking force. There is provided a group of first circuits which is disposed on each wheel and designed so that when the wheel speed signal indicates the locked state of wheel for a period in excess of a predetermined time, an output signal is immediately produced whereas when the wheel speed signal indicates the release of the locked state, the output signal is immediately stopped.

Abstract: An antiskid brake device in which the braking force on wheels is controlled while processing a wheel speed signal and a vehicle speed signal. A reference wheel speed signal setter provides a reference wheel speed signal in response to the vehicle speed by adding a predetermined slip rate which is preset on the basis of the vehicle speed. A signal level adjustor adjusts the level of at least one of the wheel speed signal and the reference wheel speed signal so as to uniformly increase a signal level of the wheel speed signal relative to the reference wheel speed signal. The wheel speed signal is compared after being adjusted in level, with the reference wheel speed signal. The signal level adjustor may be in the form of an adder which adds a wheel speed to correspondence signal of relatively small value to the wheel speed signal.

Abstract: A trouble diagnosing device of a control circuit for receiving, as input signals, signals containing information on controlled means and producing, as output signals, control signals for controlling the controlled means on the basis of the input signals, includes modulator means for modulating the input signals by means of a modulation signal having a trouble diagnosing discrimination waveform, and a trouble diagnosing circuit for producing an output signal indicating trouble in the control circuit system when the output signals of said control circuit systems produced upon receipt of the input signals modulated by the modulator means, contain an abnormal signal.In an embodiment of the invention, the modulator means modulate input signals by means of a trouble diagnosing modulation signal having such a small pulse width that electromagnetic actuators for controlling the controlled means are not able to respond thereto.

Abstract: An antiskid brake device comprising a reference wheel speed signal setting device for setting the slip rate of the wheel so as to have a relatively small value when the value of the vehicle speed signal is large and to have a relatively large value when the value of the vehicle speed signal is small, the thus set slip rate of the wheel being added to the vehicle speed signal thereby setting the reference wheel speed signal. The reference wheel speed signal setting device comprises an input section for receiving the vehicle speed signal, a logical operation section for setting such slip rate of the wheel and adding the slip rate to the vehicle speed signal for determination of the reference wheel speed signal, and an output section for delivering the reference wheel speed signal. The operational section comprises an operational amplifier, division circuits including resistors, and gain control circuits including resistors and a diode.

Abstract: A skid prevention method for reducing braking torque during a wheel lock while braking, using a main control system of an anti-skid brake device regardless of the brake input by the driver. When wheel lock is overcome, reduction of braking torque ceases. When wheel lock lasts more than a preset period without reduction in breaking torque, even when wheel lock results from failure of the main control system, the braking torque is reduced for a preset period through an auxiliary system. If the main control system reduces the braking torque for a period longer than a preset time, braking torque reduction by the main control system may be nullified, and when wheel lock lasts longer than a preset period, the braking torque may be reduced by the auxiliary control system for the preset period. An anti-skid device for carrying out this method has a brake for applying the braking torque to the wheels, a main control system for controlling the brake to reduce braking torque in case of wheel lock.

Abstract: A trouble diagnosing device for diagnosing a fault in a control circuit for controlling a plurality of electromagnetic actuators in an operating system such as a brake system. The control circuit receives a plurality of mutually independent input signals for individually controlling the operations of the electromagnetic actuators. The trouble diagnosing device includes an analog signal oscillator for feeding a trouble diagnosing analog signal to the control circuit and a trouble diagnosing circuit receiving the output signals from the control circuit for producing output signals indicating fault in the control circuit when the output signals of the control circuit include an abnormal signal.

Abstract: A method of preventing wheels of a vehicle from skidding in which a wheel-acceleration signal representative of the peripheral acceleration of a wheel is obtained by differentiating a wheel-shaped signal representative of a suitably detected peripheral speed of the wheel. The braking torque applied to the wheel during braking is controlled and held constant when the level of a wheel-acceleration signal is higher than that of a first reference wheel-acceleration signal and lower than that of a second reference wheel-acceleration signal, whereas it is increased when the level of the wheel-acceleration signal is higher than that of the second reference wheel-acceleration signal.

Abstract: An inflating device for safety air bag for an automotive vehicle is basically constructed with an air bag inflating implement, a first sensor which is installed in the neighborhood of the vehicle cabin and generates an actuating signal when a change in the running speed of the vehicle within a sampling time exceeds a predetermined value, a second sensor which is provided in a position forward of the first sensor and which detects the change in the vehicle speed at the initial stage of the collision, a third sensor which is provided within the vehicle cabin, the third sensor having no sampling time relative to a predetermined speed reduction value in the vehicle, and a memory device which is composed of an electronic circuit or mechano-electric components, in which construction the actuating signal is made to be applied to the air bag inflating implement when output signals are generated from the memory device and the first sensor simultaneously.