Akebono Brake Industry Co., Ltd.

Other

Sanyo Electric Co., Ltd.

Akebono Research and Developement Centre Ltd.

Japan Oil, Gas and Metals National Corporation

Nihon Inter Electronics Corporation

Nihon Inter Electronic Corporation

The University of Tokyo

West Japan Railway Company

Takashi Kunimi

Masatomo Mori

Masahiro Nezu

Tadao Matsunaga

Kimio Takahashi

Katsuya Miyake

Hirohisa Suzuki

Eiichiro Kuwako

Tadashi Kobayashi

Tatsuo Ogawahara

Takashi Enomoto

Satomi Okubo

Masayoshi Esashi

Yoshihiro Suda

Hiroshi Saito

Toru Sekine

Yoshiaki Hirobe

Rokurou Naya

Shougo Suzuki

Takashi Kurosawa

Masaya Sakamoto

Hideki Kakizaki

Kunio Fukaya

Naoyuki Hagiya

Fumio Kato

Shihpin Lin

Takahiro Tsunoda

Masahiko Aki

Shinichi Akutagawa

Minoru Mashiko

Atsushi Tanimoto

Kazuya Kato

Katsuka Miyake

Yukimasa Mitsude

Shinichirou Koga

Hidemi Yano

Kazuhiro Kobayashi

Tetsuya Kawanabe

Takashi Sakai

Takayoshi Yamashita

Wen-Jun Wang

Fumio Tanaka

Chieh-Jen Hung

In a method for fabricating an electrostatic capacitance-type acceleration sensor having a capacitor which electrostatic capacitance between a movable electrode and a fixed electrode changes according to the displacement of the movable electrode, the method includes: a step of forming a groove on at least one of the surface of an insulative substrate and the surface of a semiconductor substrate; a step of forming a hole in the semiconductor substrate so as to penetrate the semiconductor substrate at a position communicating with a passage formed by the groove; and a step of forming an electrode extraction hole in the insulative substrate so as to penetrate the insulative substrate, at a position communicating with the passage formed by the groove.

Method and apparatus for fabricating electrostatic capacitance-type acceleration sensor and electrostatic capacitance-type acceleration sensor

An acceleration sensor circuitof the invention includes an acceleration sensorhaving a first capacitor Cwhose capacitance changes according to a position of a first movable electrode and a second capacitor Cwhose capacitance changes as opposed to the first capacitor according to a position of a second movable electrode moved together with the first movable electrode, a first circuitA for generating a sinusoidal AC signal of a predetermined frequency, a second circuitfor generating a signal according to the positions of the movable electrodes, and an arithmetic circuitfor analyzing data in which a signal generated by the second circuitis encoded and outputting data of acceleration.

Acceleration sensor circuit

A pseudo rock includes a housing, a strain sensor, a three-axis acceleration sensor, a vibration generator and a controller. The housing has an average shape and size of rocks. The strain sensor detects a stress acting in positive and negative directions of each axis with respect to three-dimensional coordinates using the center of the housing as the origin. The three-axis acceleration sensor detects acceleration acting in each axis of the three-dimensional coordinates. The vibration generator produces vibration in a specific direction with respect to the three-dimensional coordinates. The controller converts respective detected values of the strain sensor and the three-axis acceleration sensor into vibration pulses of specific patterns and outputting the vibration pulses to the vibration generator.

Pseudo rock and analysis system using the same

Electromagnetic field transmissions between a sensor unit mounted on the inside surface of a tire and a sensor control unit mounted on the vehicle body are attenuated by the wall surface of a tire disposed between the units, and sensitivity is reduced. A booster antenna () is embedded in the tire wall surface between the sensor unit () and the sensor control unit (). The booster antenna () is a coil antenna, and is configured so that the resonance frequency, which corresponds to the impedance and capacitance component of the booster antenna coil, corresponds to the frequency fof the transmission electromagnetic field of the sensor control unit (). The booster antenna () is disposed in a position in which a magnetic coupling is formed with the coil antenna of the sensor unit (), and transmissions via the electromagnetic field between the sensor unit () and the sensor control unit () are carried out through the booster antenna ().

Tire sensor system and tire used for the same

The position of the rotation of a tire complicates the establishing of a wireless connection between a sensor unit attached to the tire and a sensor control unit attached to a vehicle body. A reflection plate is attached to an inner surface of a wheel housing at a position different from that of a sensor control unit. A transmission electromagnetic field from the sensor control unit is reflected by the metal reflection plate and transmitted to a sensor unit rotated to a position to which the field does not readily reach directly from the sensor control unit. The sensor unit varies an impedance of a coil antenna in accordance with transmission data, and generates a variation in the transmission electromagnetic field. The variation is detected via the reflection plate as a variation in a transmission load of the sensor control unit, and the transmission data from the sensor unit is detected in the sensor control unit.

Tire sensor system and vehicle body having the same mounted thereon

A tire inflation pressure determining system is provided in which measurement results are transmitted to the exterior without providing a high precision oscillation circuit to a tire-mounted air pressure determining system. An LC resonance circuit is composed of a coil Ls and an inflation pressure sensor in which the electric capacitance varies in accordance with tire air pressure. The fluctuations of the electromagnetic field having a frequency fgenerated by a sensor control unit are sensed in a coil L, a clock is generated based on the sensed fluctuations, the clock is inputted to a coil Le that is transformer coupled to the coil Ls, and the LC resonance circuit is excited. The output voltage of the LC resonance circuit is converted to digital data in an A/D conversion circuit in correspondence with the intensity of the resonance, the impedance of the coil Lis varied in accordance with the bit sequence constituting the data, and a modulation is thereby generated in the voltage of a coil Lof the sensor control unit via the electromagnetic field.

Tire inflation pressure determining system and tire inflation pressure determining apparatus

A method of estimating an eccentric position of an acceleration sensor for a double turntable-type acceleration generating apparatus includes the steps of mounting the acceleration sensor on an auxiliary rotating body; rotating the auxiliary rotating body at a constant frequency with a main rotating body held at a standstill; measuring an output signal from the acceleration sensor; determining an amount of eccentricity in an X-axis direction of the acceleration sensor from the frequency of the auxiliary rotating body and the output signal; and determining an amount of eccentricity in a Y-axis direction by using tangential acceleration generated by the rotation of the auxiliary rotating body in a state in which the amount of eccentricity in the X-direction is set to substantially zero.

Method of estimating an eccentric position of an acceleration sensor and acceleration generating apparatus with an eccentricity adjuster

An eccentric error corrector for a rotary-type acceleration generating apparatus. The eccentric error corrector includes a large-diameter turntable and a small-diameter turntable. The large-diameter turntable is rotated by a first servo motor. The small-diameter turntable is mounted on the outer periphery portion of the large-diameter turntable and rotatable by a second servo motor, in which an acceleration sensor is attachable to the small-diameter turntable. The eccentric error corrector includes a DC-component remover removing only the DC component from an output signal of the acceleration sensor attached on the small-diameter turntable.

Eccentric error corrector and method of eccentric error correction for acceleration sensor in acceleration generating apparatus

To improve a response rate and an impact detection precision of an auxiliary acceleration sensor device for an air bag system, an auxiliary acceleration sensor device includes a longitudinal G sensor for sensing a longitudinal acceleration G of a vehicle, and lateral G sensor for sensing a lateral acceleration G of the vehicle. The longitudinal G sensor includes a constant current source circuit, a detector portion for outputting an electrical signal representative of a longitudinal acceleration G, and an amplifier portion for amplifying the signal received from the detecting portion. The comparator includes comparing elements that compare the voltage values corresponding to longitudinal threshold values Tf to Tf of the longitudinal acceleration G with an output signal of the amplifier portion. Lateral G sensor includes a constant current source circuit, a detector portion for outputting an electrical signal representative of a lateral acceleration G, and an amplifier portion for amplifying the signal received from the detecting portion. Comparator means includes comparing elements which compare the voltages corresponding to lateral threshold values Ts to Ts of the lateral acceleration G with the output signal of the amplifier portion. An OR circuit coupled for reception with the comparator means outputs a signal to a main controller of an air bag control system when predetermined conditions are satisfied.

Auxiliary acceleration sensor device for an air bag system

Semiconductor acceleration sensor and its self-diagnosing method

A turntable acceleration generating apparatus includes a first servo motor, a large-diameter turntable rotated by the first servo motor, and a small-diameter turntable being mounted on the large-diameter turntable at a position offset from the central axis of the large-diameter turntable such that the small-diameter turntable is rotated by a rotary shaft. Furthermore, the turntable acceleration generating apparatus includes a signal line for deriving signals from an acceleration sensor located on one of the sides of the large-diameter turntable, and a control signal line for applying control signal to a second servo motor located on the other side of the large-diameter turntable, wherein the large-diameter turntable is grounded such that the large-diameter turntable prevents noise leakage from the control signal line to the signal line.

Turntable acceleration generating apparatus

A semiconductor acceleration sensor including a central board having a movable electrode section, an outside board having a stationary electrode section, and a sealing insulating section for joining the central board and the outside board which are laminated on each other, wherein the sealing insulating section has a conductive layer, and the conductive layer is a sealing member or an anodic bonding electrode.

Semiconductor acceleration sensor and manufacturing method thereof

An acceleration sensor includes a first substrate, a second substrate and a third substrate. The second substrate has a through-hole, a first contact formed on an inner surface of the through-hole, and a first bonding pad connected to the first contact. An electrically conductive ball is accommodated in the through-hole. The third substrate has a recess, a second contact formed in the recess contacting the bottom of the electrically conductive ball, and a second bonding pad connected to the second contact.

Acceleration sensor and method for manufacturing thereof

A semiconductor acceleration sensor comprising a rectangular semiconductor substrate on the moving electrode side and a rectangular semiconductor substrate on the fixed electrode side laminated on each other, the moving electrode side substrate being formed with a heavy weight and a thin cantilever, a moving electrode being provided on the heavy weight, a first electrostatic attraction electrode being provided on the cantilever, the fixed electrode side substrate being formed with a fixed electrode at a position opposed to the moving electrode and a second electrostatic attraction electrode at a position opposed to the electrostatic attraction electrode. The first and second electrostatic attraction electrodes are placed facing each other. A predetermined spacing is provided between the electrostatic attraction electrodes and a predetermined voltage is applied therebetween.

Semiconductor acceleration sensor using semiconductor microworking

In a semiconductor acceleration sensor, a weight and thin beam parts adjacent to the weight are formed on a substrate, a moving electrode is formed on the weight, and a fixed electrode is formed at a position of the other substrate opposed to the moving electrode. Both the electrodes come in contact with each other and conduct as a result of acceleration on the weight, whereby the semiconductor acceleration sensor operates. The fixed electrode or the moving electrode is formed with a projection toward the opposed electrode and the projection and the electrode come in contact with each other and conduct by action of acceleration with a predetermined spacing held between both the electrodes for preventing occurrence of chattering caused by the electrostatic attraction force between both the electrodes.

Semiconductor acceleration sensor

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Tokyo, Japan

Takashi Kunimi