Abstract: An accelerometer for automobiles is disclosed which is mounted on an electrically insulating plate (i.e., a printed circuit board) accommodated within an electrically conductive casing. The electrical connections from the electrodes of the piezoelectric element to the inputs of the charge amplifier are effected by a wiring pattern formed on the insulating plate. The casing consists of an open box-shaped base and a plate-shaped cover, a packing member being interposed therebetween, wherein an electrical connection between the base and the cover is provided by the fixing screws for fixing the cover to the base. The cover has a central recess in which through-type capacitors for producing hermetically sealed electrical connections through a wall of the casing are accommodated.

Abstract: Ultrasonic waves are transmitted from an ultrasonic transmitter mounted on a vehicle towards a road surface. An ultrasonic receiver mounted on the vehicle receives ultrasonic waves reflected from the road surface and generates a signal which is amplified by an amplifier. The amplified signal is compared with a reference signal to detect components in the amplified signal due to obstacles on the road surface. The magnitude of the reference signal and/or the amplification factor of the amplifier is controlled to maintain a constant ratio between the average of the reference signal and the average of the amplified signal.

Abstract: A suspension control device including a control device for variably controlling a damping force of a suspension to an optimum value by determining a magnitude of acceleration is vertical opposite directions of a vehicle body which magnitude is equal to or greater than a predetermined level and measuring the accumulated duration time of a sprung resonance which is detected by a cycle of vibration of the vehicle body from a timing of the determination of the magnitude. In another aspect, the suspension control device includes a control device for outputting a command for increasing a damping force when a magnitude of acceleration in vertical opposite directions of a vehicle body is determined to be equal to or greater than a predetermined level, and measuring the number of repetitions of a sprung resonance which is detected by measuring a cycle of vibration of the vehicle body from a timing of the determination of the magnitude.

Abstract: An ultrasonic obstacle sensor for sensing an obstacle on a road surface is disclosed which projects ultrasonic waves in the form of pulses toward the forwardly distant surface of a road in a downwardly inclined forward direction, and which is able to discriminate an obstacle on the road surface through reflection waves therefrom in a most effective and reliable manner. To this end, a timing instructor intermittently generates an instruction signal, based on which ultrasonic waves are generated. An ultrasonic transmitter projects the ultrasonic waves thus generated toward a road surface, and the reflected waves therefrom are received by an ultrasonic receier which in turn generates a reception signal. A reception signal processor AM detects the reception signal to provide an AM modulation signal. A time calculator calculates a time elapsing from the generation of the instruction signal.

Abstract: A shock absorber control apparatus which performs a fuzzy inference by use of a predetermined fuzzy rule regarding comfortable ride, steering stability and grounding efficiency corresponding to a detected running condition of a vehicle, thereby setting an optimum damping force. A shock absorber control apparatus which fetches a plurality of specified frequency components from a vertical acceleration signal of a vehicle body so as to perform a fuzzy inference by use of a fuzzy rule corresponding to a quantity of each frequency component, thereby setting an optimum damping force.

Abstract: A controlling circuit for an actuator which is provided with a change-over switch for selecting a desired rotational position of a rotating shaft of the actuator, exciting circuit forming device for selectively magnetizing a plurality of electro-magnets in order to control rotation of the rotating shaft to be in a selected desired rotational position in response to an outputted change-over signal, and electrifying switching device for supplying electricity to the electro-magnets only for a predetermined duration from the time when selection of the rotational position of the rotating shaft is changed over by the change-over switch, wherein there is no generated any unnecessary heat for the actuator and construction of the circuit can be more simplified.

Abstract: A suspension control apparatus for an automotive vehicle has a plurality of suspension units which are disposed between each of the wheels of the vehicle and the vehicle body. A plurality of actuators for controlling the characteristics of the suspension units are controlled by a control unit in response to the output of an acceleration sensor. The ground circuit of the acceleration sensor is connected to the ground circuit of the control unit.

Abstract: There is disclosed a malfunction diagnostic apparatus for a vehicle control system wherein a period of time after the last detection of a malfunction state is set by a timer, to inhibit the display of stored information when the period of time has exceeded over a specific period of time, and to release the inhibited display in accordance with an inhibition release signal.

Abstract: Disclosed is a control apparatus for a vehicular suspension system having a plurality of suspension units each disposed between a road wheel and the body of a vehicle for suspending the corresponding road wheel from the vehicle body. The control apparatus includes a control unit which is connected to receive the output signals from an acceleration sensor, a vehicle-speed sensor and a steering sensor for calculating the rolling state of the vehicle due to a transverse acceleration thereof and controlling the respective suspension units based on the calculated rolling state of the vehicle so as to suppress the rolling thereof.

Abstract: A suspension control apparatus for an automotive vehicle has a plurality of suspension units which are disposed between each of the wheels of the vehicle and the vehicle body. An acceleration sensor measures the lateral acceleration of the vehicle body. A contol unit corrects the output of the acceleration sensor for drift of the neutral point of the sensor from a prescribed value. Based on the corrected output, the control unit controls the suspension units so as to suppress rolling of the vehicle body.

Abstract: A suspension control apparatus and a method for a vehicle having a plurality of suspension units each disposed between a road wheel and the body of a vehicle for suspending the corresponding road wheel from the vehicle body. The suspension control apparatus includes a control unit which is connected to receive the output signals from an acceleration sensor, a vehicle-speed sensor and a steering sensor for calculating the rolling state of the vehicle due to a transverse acceleration thereof and controlling the respective suspension units based on the calculated rolling state of the vehicle so as to suppress the rolling thereof. The control unit serves to determine the period or frequency of change or reversal of the direction of the detected transverse acceleration of the vehicle, and control the suspension units so as to stop the roll-suppression control when the frequency of reversal exceeds a prescribed level.

Abstract: Disclosed is a suspension control apparatus for a vehicle having a plurality of suspension units each disposed between a road wheel and the body of a vehicle for effectively and quickly correcting any deviation of the vehicle height from a normal height level immediately upon finishing of active suspension control operations. Priority is determined for vehicle-height control and various active suspension control operations such as roll control, nose-dive and squat control, and pitching and bouncing control so that normal vehicle-height control is stopped or inhibited during active suspension control operations are being carried out, thereby preventing the traveling attitude of the vehicle from being made unstable.

Abstract: When vibrations having a period at which pitching tends to occur in a vehicle body is detected, if its amplitude falls out of the range between "H" and "L", a control unit increases the damping force of each suspension unit by using an actuator. In addition, if the amplitude falls out of the range between "HH" and "LL", the control unit supplies a predetermined amount of air to each air spring chamber in response to an upward displacement of vehicle height, and exhausts a predetermined amount of air from each air spring chamber in response to a downward displacement of vehicle height.

Abstract: If a deceleration exeeds first set value G1 within set time T1 after the brake is depressed, a set amount of fluid is supplied to the fluid spring chamber of each front-wheel suspension unit. If a deceleration exceeds the second set value G2 when set time T1 or more has elapsed upon this operation, a set amount of fluid is exhausted from the fluid spring chamber of each rearwheel suspension unit. With this operation, since braking action for gradually increasing a deceleration is controlled by two stages, uncomfortableness which passangers feel in anti-nose-dive control can be greatly reduced. In addition, control is not performed only by depressing the brake pedal if an acutal deceleration is smaller than first set value G1.

Abstract: A suspension device for automobile performs changing-over of the damping force of a shock absorber and the spring constant of a suspension spring by an output from an acceleration sensor or an output from a road clearance sensor mounted on the vehicle body. The changing operation is not performed by magnitude of an output but is performed only when an output greater that a predetermined level continues for a predetermined time period to avoid unnecessary change-over operations of the suspension characteristic during cruising a rough road.

Abstract: In a suspension device for automobile having a shock absorber provided with a damping force change-over mechanism and a suspension spring provided with a spring constant change-over mechanism, a power source to perform both the changing-over of the damping force of the shock absorber and the spring constant of the suspension spring depends on a fluid pressure source equipped in the automobile and the fluid pressure from the pressure source is controlled by an electromagnetic valve.

Abstract: A suspension system for an automobile wherein after having been changed to a "HARD" mode upon commencement of the turning movement, the characteristic of the suspension is not restored to the standard condition until completion of the turning movement is detected so that a stable running performance is obtained irrespective of the status of the curve of a road while good riding comfort at normal running is also maintained.

Abstract: An apparatus for measuring the flow velocity by detecting the number of Von Karman's vortex streets or Strouhl vortexes by utilizing heating wires, said apparatus comprising a vortex generator disposed in a fluid to be measured, at least one heat-sensitive element which detects the flow velocity or flow rate of the fluid in the form of change of temperature caused by said vortex generator, and which produces detection signals that represent change in frequency of the electric signals, an operational amplifier for amplifying the detection signals, and a feedback circuit which feeds the output of said operational amplifier back to said heat-sensitive element such that its temperature is maintained substantially constant, and such that the preset temperature of said heat-sensitive element changes in response to the output of said operational amplifier, whereby the frequency characteristics thereof are improved and the apparatus can be stably started under any conditions.

Abstract: A flow velocity measuring apparatus includes a vortex-generating member disposed in the flow path and a temperature-resistance converting element positioned in contact with vortexes produced at the downstream side. A bridge circuit includes as one side the temperature-resistance converting element, and an amplifier circuit amplifies the output of the bridge circuit to provide a detection signal having a frequency corresponding to the periodic change in temperature of the element due to cooling action of the vortexes.

Abstract: An air flow rate measuring device for use with an internal combustion engine in which a signal accurately representing the air flow rate of intake air in an intake air passage of the engine is always available. A first, frequency signal is generated which has a frequency which varies in proportion to frequency of vortices in a vortex stream in the intake air passage. An analog signal is provided which has an amplitude which varies in accordance with an average of the air flow rate in the intake air passage. By using these signals together, an accurate indication of the air flow rate in the intake air passage is continuously provided.