Bridgestone Corporation

Kabushiki Kaisha Bridgestone

Kokusai Denshin Denwa Kabushiki Kaisha

Hidetoshi Yokota

Hiroshi Morinaga

Toshiyuki Watanabe

Yoshihiro Ito

Masami Ishikura

Akio Kusano

Yoshiyuki Waki

Koji Otani

Seiji Ishikawa

Taiga Ishihara

Tooru Asami

Kento Hirohata

A pneumatic tire in which a cavity resonance sound is reduced while punctures are easily repaired with a puncture sealant. The pneumatic tire has a fibrous region where short fibers are bonded onto an inner surface of the tire. A circumferential fiberless region where short fibers are not bonded onto the inner surface of the tire extends circumferentially between both ends of a tread ground contact area.

Pneumatic tire

The frequency of an information signal indicative of a-vibration of a wheel detected by an acceleration sensor mounted to a wheel; or a change in the pressure of a gas in a tire detected by a pressure sensor installed in the tire, is analyzed. The band value of the obtained vibration spectrum or pressure change spectrum is detected, and a vibration level or pressure change level at the detected frequency band is compared with: a vibration level table showing the relationship between road friction coefficient &#x3bc; and vibration level; or a pressure change level table showing the relationship between road friction coefficient &#x3bc; and pressure change level, to estimate a road friction coefficient &#x3bc;. Therefore, it is possible to estimate the value of road friction coefficient &#x3bc; accurately and improve the safety of a car.

Method and apparatus for estimating road surface state and tire running state, ABS and vehicle control using the same

A purpose of the present invention is to provide a rim wheel and a tire rim assembly which are capable of effectively reducing cavity resonance of a tire, and accordingly, enhancing quietness and riding comfort. A plurality of cap membersis arranged on an outer circumferential surface of a rimin a circumferential direction thereof, diaphragms are disposed inwardly of each cap member, and a plurality of sub-air chambersis formed between the rimand the cap membersin a rim circumferential direction. The tire main air chamberis connected to the sub-air chambersthrough communicating holesformed on the cap members. The sub-air chambersand the communicating holesconstitute a Helmholtz resonance noise absorber that can absorb vibration with specified frequencies. Further, since the sub-air chamberis not formed in a continuous annular shape in a tire circumferential direction, occurrence of cavity resonance can be suppressed and a substantial reduction in noise can be secured.

Rim wheel, and tire-rim assembly

The output level of vibration of a portion below the spring of a vehicle detected by a sensor, and its frequency is converted to obtain the frequency spectrum of the vibration level. Next, an operation is carried out on at least two vibration levels, at different frequency bands. The computed value is compared with a master curve showing the frequency spectrum of vibration level stored in vibration level storage to estimate the condition of a road surface so as to estimate the running state of the vehicle. Further, the running state of each tire including air pressure is detected from the vibration level of the portion below the spring to estimate the running state of the vehicle. Thereby, a multi-function sensing system is constructed for estimating the condition of a road surface or the running state of the tire with one sensor.

Method for estimating vehicular running state, vehicular running state estimating device, vehicle control device, and tire wheel

An amount of data to be distributed to each receiving terminal is dynamically controlled for each receiving terminal in response to a congestion of each of plural receiving terminals. When a determination of an RR (Reception Report) returned from the receiving terminal results in a very low rate of packet loss, an adaptive control mixer distributes communication data transmitted from a transmitting terminal to the receiving terminal without reducing the communication data. On the other hand, the determination of the RRs returned from the receiving terminals results in a high rate of packet loss, for example, 50% and 90%, respectively. In this case, the adaptive control mixer reduces, for example, 50% of the communication data transmitted from the transmitting terminal and then distributes the data to the one receiving terminal. The adaptive control mixer reduces, for example, 90% of the communication data and then distributes the data to the other receiving terminal.

Method and apparatus for dynamic data rate control over a

A pneumatic radial tire which is excellent in drainage and capable of reducing air-column-tube resonance sounds in circumferentially extending grooves to decrease noises. The pneumatic radial tire comprises a tread provided thereon with a groove extending circumferentially in the circumferential direction of the tire and a vibration buffer wall having essentially an identical cross-sectional shape provided near the sidewall of said circumferentially extending groove, wherein the height of the outside edge of the vibration buffer wall in the radial direction of the tire is lower than the height of the outside edge of the circumferentially extending groove in the radial direction of the tire.

Growing community of inventors

Kodaira, Japan

Hidetoshi Yokota