Aisin Seiki Kabushiki Kaisha

Toyota Jidosha Kabushiki Kaisha

Yutaka Iguchi

Shuuichi Buma

Toshihiro Kobayashi

Kunihito Sato

Toshio Aburaya

Takashi Yonekawa

Kazuo Sato

Masaki Kawanishi

Kouichi Kokubo

Masayuki Sato

Shigemitsu Suzuki

Kenji Hayase

Hisayasu Mase

Hidemori Tsuka

Kohji Ariga

Teruaki Akata

Atsushi Watanabe

In order to realize, without inviting cost increase, a control for maintaining a pressure of fluid delivered from a pump at a target value, a pump control unit is provided with a driver control unit controlling a rotational speed of a hydraulic pump through adjustment of a duty ratio of a PWM signal driving excitation coils of an electric motor. Further, the pump control unit is provided also with a signal correction circuit configured to convert a current flowing in the excitation coils to a voltage signal with using a shunt resistor and to divide the voltage signal with using a voltage division ratio setting circuit and to shorten an ON signal of the PWM signal by increasing the divided voltage. The voltage division ratio setting circuit has a characteristics of setting the divided voltage higher, the longer an ON period of the PWM signal.

Current limited pulse width modulation controlled motor

A fixing member includes a case member provided with at least a substrate supporting member adjusted to support a substrate and integrally provided with a connector, a cap member adjusted to be fixed to the case member, at least an external force transmitting portion extending at the substrate supporting member between the substrate supporting member and the cap member and adjusted to transmit an external force subjected to the connector to the cap member while the case member has been fixed at the cap member.

Fixing member

A malfunction detection device for a wheel speed sensor includes a comparison circuit for comparing a wheel speed signal output from a wheel speed sensor with a predetermined voltage. A calculation circuit is provided for selectively increasing or decreasing a counter according to an output signal of the comparison circuit. A malfunction signal output circuit outputs a malfunction signal when the counter of the calculation circuit reaches a predetermined value.

Malfunction detection device and method for a wheel speed sensor

An angular rate detector includes an oscillator having a first terminal to which a drive voltage is applied, a second terminal where a signal occurs having a given phase displacement with respect to a signal appearing at the first terminal during a resonance of the oscillator and a third terminal where a signal occurs having a phase which changes in accordance with an angular rate. An oscillator is provided for producing an alternating signal which corresponds to the drive voltage applied to the first terminal in accordance with the signal appearing at the second terminal. A frequency multiplier responsive to a signal which corresponds to the oscillation frequency of the oscillator produces a clock pulse having a frequency higher than the oscillation frequency. A phase difference pulse signal is produced having a duty cycle which changes in accordance with a phase difference between the signal occurring at the third terminal of the oscillator and either the signal applied to the first terminal or the signal occurring at the second terminal. A counter is provided for counting the clock pulses during a time interval when the phase difference pulse signal assumes either a high or a low level.

Angular rate detector

An electrical circuit for reliably starting the oscillation of an oscillator comprising a cylindrical piezoelectric body on which an exciting electrode, a feedback electrode which causes an oscillation, and an electrode for detecting an angular rate are mounted. The electrical circuit includes an exclusive OR gate for detecting a phase difference between an exciting voltage and a voltage developed at the feedback electrode, a circuit for integrating an output voltage from the gate and a band pass filter having its resonant frequency shifted in proportion to a voltage from the integrating circuit. The band pass filter is effective to provide an automatic adjustment of a phase difference of a voltage, which is actually fed back to the exciting electrode, with respect to a voltage developed at the feedback electrode. In this manner, if the natural frequency of the oscillator is offset from a reference value, it is assured that a phase difference between the exciting voltage and the voltage which is actually fed back to the exciting electrode be equal to 360.degree.. The electrical circuit also includes an oscillation starter circuit which increases the gain of a positive feedback loop including the filter for a given time interval immediately after the turn-on of the power.

Oscillator unit

A suspension pressure control system on a vehicle applies a pressure which is proportional to a current level supplied to a solenoid of a pressure control valve to a shock absorber associated with respective one of suspensions from the valve. An electronic controller controls the current level to maintain an attitude of a vehicle substantially constant in spite of any change of longitudinal and lateral acceleration, which are detected by acceleration sensors. If a driver on the vehicle closes test indication switches TSW1 and TSW2, indicates 'high' by a height indication switch HSW and rotates a steering wheel on the vehicle by B toward right, the vehicle laterally inclines such that a height of the left side of the vehicle rises up and a right side falls down responding to the rotation of the steering wheel. The inclination increases as the rotation of the steering wheel increases. The inclination decreases when the steering wheel rotates inverse direction toward the neutral position. When the steering wheel rotates beyond the neutral position toward left, the vehicle laterally inclines such that the height of the left side of the vehicle calls down and the right side rises up responding to the rotation of the steering wheel.

Pressure control system for suspension

In a fluid pressure type active suspension in a vehicle such as an automobile, having a fluid pressure type actuator supporting a vehicle body from a wheel so as to be able to vary a height of the vehicle body relative to the wheel in accordance with a fluid pressure supplied to its fluid chamber, a fluid supply passage for supplying a working fluid to the fluid chamber of the actuator, a fluid exhaust passage for exhausting the working fluid from the fluid chamber of the actuator, and a pressure control circuit including a switching-over valve traversing the fluid supply passage and the fluid exhaust passage so as to be operated by a pilot pressure to selectively connect the fluid chamber of the actuator with either the fluid supply passage or the fluid exhaust passage for controlling the fluid pressure supplied to the fluid chamber of the actuator, a variable throttle valve for generating the pilot pressure for operating the switching-over valve from the pressure of the working fluid in the fluid supply passage by releasing a part of the working fluid therefrom, and a throttle control device for controlling the variable throttle valve so as to control the pilot pressure to a target value, the pressure control circuit comprises a means for modifying the target value to be lowered when the difference between the pressure of fluid in the fluid supply passage means at an upstream side of the pressure control circuit and the target value is smaller than a certain threshold value.

Fluid pressure type active suspension with bypass control for working

A rotation angle detecting device, that outputs a position data and a control data, each having a prescribed number of bits, as a serial data. A position-data generating circuit, that includes first detecting circuits, that are turned on or off according to the angle of rotation of a rotary shaft, outputs a position data, having a prescribed number of bits, according to the angle of rotation. A state-data generating circuit, that includes second detecting circuits, that are turned on or off according to the signals from the first detecting circuits, outputs a state data, having a prescribed number of bits, that indicate the states of operation of the first detecting circuits. The state data is transformed to a control data after passing through a data selector and a control code generating circuit. The last bit of the serial data is a parity bit.

Growing community of inventors

Kariya, Japan

Yutaka Iguchi