Bridgestone Corporation

Kabushiki Kaisha Bridgestone

Birdgestone Corporation

Masanobu Toyofuku

Takao Kokubu

Masaharu Oku

Koji Takao

Yoshinori Imamura

Hiromitsu Ichikawa

Hiromasa Hada

Shuhei Tsuchie

A tire internal pressure measuring system includes a detector for detecting the internal pressure of a tire, and an acquisition device for acquiring data relating to the internal pressure of the tire detected by the detector. An antenna unit of the acquisition device generates induced electromotive force in an antenna unit of the detector by electromagnetic induction, and acquires a resonant waveform in tune with the resonance of an LC resonance circuit configured from a capacitance sensor charged with the electromotive force generated in the antenna unit and the antenna unit. The acquired resonant waveform is frequency-divided, and a capacitor (C) is charged during a period from the rising edge to the falling edge of the waveform obtained by the frequency dividing. The value of charged voltage is associated with the tire internal pressure.

Tire inner pressure measurement system

A tire pressure information monitoring system includes a pressure sensor () for detecting air pressure within a tire, and a temperature sensor () for detecting temperature within the tire. The monitoring system further includes a CPU () that operates with a high frequency clock to send command to the pressure sensor () and the temperature sensor () to acquire internal information of the tire, and thereafter operates with a low frequency clock until stabilizing time of the pressure sensor () and the temperature sensor () elapses. The CPU then operates with a high frequency clock to transmit the internal information of the tire, which has been acquired by the pressure sensor () and the temperature sensor (), to an external receiver at a constant time interval, and thereafter operates with a low frequency clock until the constant time interval elapses.

Tire pressure information monitoring system operating with high and low frequency clocks

A tire sensor device comprising sensor modulesA toD, each comprising a sensor, a communication module having a communication function and a power regenerating circuit, and an antenna; and a base station comprising an internal communication device for communication with the sensor modulesA toD, an information processing device for processing tire information signals from the sensor modules, an external communication device for communicating with a car control deviceon the car body side and a power source. The sensor modulesA toD and the base stationare arranged in the tire and constitute an intra-tire LAN. Tire information signals transmitted from the sensor modulesA toD are processed by the base stationand transmitted to the car control deviceso that appropriate tire information can be obtained and the size and power consumption of the sensor device can be reduced.

Tire sensor device and tire information transmission method

An electronic device () includes a transmitter substrate () for generating information to be measured by a sensor () arranged in a partitioned space () which is partitioned by a tyre () and a rim wheel (), a signal line () extended from the transmitter subs/rate ()to outside of the partitioned space () and passing through an inner side of an air valve () provided at the rim wheel (), the signal line () being formed by a core wire () made of a conductor and a coaxial cable () covering that core wire (), and an antenna () for transmitting radio waves containing the information (such as information of the tyre) generated by that transmitter substrate (), the antenna () being connected to the signal line () and positioned outside the air valve ().

Electronic device and tyre

A method for directly and accurately estimating friction coefficient of a road surface independently from the slip rate is disclosed. The method measures tangential and vertical forces acting on an elastic bodyof an elastic wheel, and calculates the friction coefficient of a road surface based on the measured values of these forces and angular rate of the wheel

Road surface friction coefficient estimating method, signal multiplex transmission method and signal multiplex transmission device

A sensor unit bodyof a tire pressure sensor unitis provided with external signal-importing terminalsfor rewriting data of self-identification code stored in a ROM, so that a complex operation of associating the self-identification code of the sensor unit with its mounting position in the vehicle is eliminated by rewriting the self-identification code of the sensor unitafter the replacement to be identical to the self-identification code of the sensor unitbefore the replacement, when a tire wheel is replaced due to a breakdown of the tire unit or a replacement between a summer tire and a winter tire.

Growing community of inventors

Kodaira, Japan

Masanobu Toyofuku