Denso Corporation

So-ken Corporation

Nippon Soken, Inc.

Denso Corpora Tion

Tohoku University

Pacific Industrial Company, Ltd.

Takatoshi Sekizawa

Masashi Mori

Nobuya Watabe

Yoichiro Suzuki

Akira Takaoka

Youichirou Suzuki

Noriaki Okada

Ryosuke Kanbayashi

Takashi Saitou

Kenichiro Sanji

Munenori Matsumoto

Naohito Takasuka

Hideyuki Ikemoto

Hidenori Osai

Youichiro Suzuki

Yasuhiro Tanaka

Yuuji Kakuya

Suguru Matsushita

Yoshinori Hayashi

Akihiro Taguchi

Hiromasa Hayashi

Noritaka Hirao

Takao Araya

Gorou Inoue

Ryoichi Ijima

Mitsugi Ohtsuka

Toshifumi Shimoda

Hiroki Kuwano

Hironori Kato

A road surface state determination device includes a tire-side device and a vehicle-body-side system. The tire-side device is attached to each of a plurality of tires included in a vehicle. The vehicle-body-side system is included in a body of the vehicle. The tire-side device may output a detection signal corresponding to a magnitude of vibration of the tire. The tire-side device may sense the detection signal and generate road surface data indicative of a road surface state appearing in a waveform of the detection signal. The tire-side device may transmit the road surface data. The vehicle-body-side system may perform bidirectional communication with the tire-side device and receive the road surface data. The vehicle-body-side system may determine the road surface state of a road surface on which the vehicle is traveling based on the road surface data.

Road surface state determination device and tire system including same

A tire wear detection apparatus includes a tire side device and a vehicle body side system. The tire side device includes a vibration detection unit, a vehicle speed estimation unit, a signal processing unit, and a first data communication unit. The vibration detection unit is configured to output a detection signal. The vehicle speed estimation unit is configured to estimate the vehicle speed. The signal processing unit is configured to generate wear data. The vehicle body side system includes a second data communication unit and a controller. The controller has a wear determination unit configured to determine a tire wear state based on the wear data. The signal processing unit is configured to acquire the detection signal within a detection signal acquiring range, and calculate a level value of a vibration level of the acquired detection signal within a predetermined frequency range based on a natural frequency of the tire.

Tire wear detection apparatus

A wheel position detection apparatus applied to a vehicle including a vehicle body attached with multiple travelling wheels. The apparatus includes: multiple transmitters respectively disposed at travelling wheels; and a receiver disposed at the vehicle body. The transmitter includes: an acceleration sensor outputting a detection signal according to an acceleration including a gravitational acceleration component being varied by a rotation of the corresponding travelling wheel attached with the transmitter; and a first controller creating a frame including unique identification information, and transmit the frame in response to the receiver outputting a transmission command. The receiver includes a second controller executing a wheel position detection through: identifying, from each set of the unique identification information included in the frame, which of the travelling wheels is attached with the transmitter having transmitted the frame; and registering the travelling wheels in association with the unique identification information of the transmitter.

Wheel position detection apparatus and tire pneumatic pressure monitoring system including same

A tire device has a tire side device and a vehicle body side system, and determines a road surface condition and detects a tire wear state. The tire side device includes a vibration detection unit that outputs a detection signal according to a magnitude of a tire vibration, a control unit extracts a feature amount during one rotation of the tire, and a first data communication unit that transmits a road surface data including a feature amount. The vehicle body side system includes a second data communication unit that receives road surface data, a road surface determination part that determines a road surface condition based on the road surface data, an integral calculation part that calculates an integral value of the feature amount in a specific frequency band included in the road surface data, and a wear determination part that detects the tire wear state from the integral value.

Tire device

A control unit of a tire side device has a feature amount extraction part, a feature amount storage part, a change determination part, a vehicle speed estimation part, and an algorithm switching part. The change determination part determines whether or not there is a change in the road surface condition based on a present feature amount and a previous feature amount stored in the feature amount storage part, and transmits a road surface data including the present feature amount when there is a change in the road surface condition. The algorithm switching part switches based on the vehicle speed estimation by the vehicle speed estimation part whether to transmit the road surface data from the transmission unit when the road surface condition is changed, or to transmit the road surface data without determining whether or not the road surface condition is changed by the change determination part.

Tire side device and road surface condition determination device containing same

A transceiver of a spare wheel includes a sensing unit having a pressure sensor and an acceleration sensor configured to output a detection signal according to a tire pressure of the spare wheel and an acceleration generated in the spare wheel, a first control unit configured to create a frame that processes the detection signal indicating the tire pressure and stores it as data related to the tire pressure, and a first transmitter receiver configured to transmit the frame. A receiver includes a second transceiver configured to receive a frame and transmit a response signal indicating that the frame is received and a second control unit configured to detect the tire pressure and transmit a response signal from the second transceiver when the frame is received.

Tire pressure monitoring system

A tire side device includes a vibration detection unit that outputs a detection signal according to a magnitude of vibration of a tire, an air pressure detection unit that detects the tire pressure, a data acquisition unit that calculates a contact length of the tire with a road surface based on the detection signal and acquires a wheel load data that is a data related to the wheel load based on the contact length, and a data transmission unit that transmits a data related to the tire pressure and the wheel load data. A vehicle side device includes a receiving unit that receives data on tire pressure and wheel load data, a threshold setting unit that sets an alarm threshold for tire pressure based on the wheel load data, and an alarm determination unit that determines that the tire pressure has decreased when the tire pressure indicated by the data on the tire pressure decreases below the alarm threshold.

Tire pressure monitoring system including tire side and vehicle side devices

A tire wear detection apparatus for a vehicle includes a tire side apparatus and a vehicle body side system. In response to a wet road surface being detected, from a vibration waveform of a tire indicated by a detection signal according to a magnitude of a vibration of the tire, the tire side apparatus is configured to (i) acquire a peak level value of a vibration level at a stepping time at which an apparatus corresponding position in the tire corresponding to an arranged position of the tire side apparatus starts to contact the road surface, and/or (ii) calculate a level value of the vibration level in a post-kicking range after the apparatus corresponding position kicks to separate from the road surface, so as to generate a wear data indicating a wear state of the tire.

Tire wear detection apparatus having a signal processor in the tire side apparatus including a state detection unit and level acquisition unit and/or level calculaton unit

A tire system is configured to enable a general-purpose communication device to establish data communication with a tire-side device, thereby enabling transmission of data indicating a tire-related condition from the tire-side device to the general-purpose communication device. The general-purpose communication device acquires the tire-related condition, and reports the tire-related condition to the user via a notification unit. Based on the above, it is possible to report the tire-related condition via the general-purpose communication device based on the communication between the general-purpose communication device and the tire-side device.

Tire system

A road surface condition identification apparatus for identifying a road surface condition is provided. The road surface condition identification apparatus includes a vibration detector unit configured to output a detection signal being an analog signal according to magnitude of vibration of the tire. For identifying the road surface condition, the road surface condition identification apparatus performs A-D conversion of converting the detection signal of the vibration detector unit into a digital signal. Based on data on vehicle speed, the road surface to condition identification apparatus sets a conversion range of the magnitude of the vibration of the tire used in the AD conversion from the detection signal into the digital signal.

Road surface condition identification apparatus

A tire-side device is attached to a tire included in a vehicle and applied to a tire apparatus for estimating a condition of a road surface on which the vehicle travels. The tire-side device includes: a vibration detector outputting a detection signal according to a level of vibration of the tire; a controller having a feature quantity extraction device extracting a feature quantity of the detection signal in one rotation of the tire; and a transmitter transmitting road surface data including the feature quantity extracted by the feature quantity extraction device.

Tire-side device and tire apparatus including the same

When information related to road surface conditions is conveyed from a vehicle body side system to a tire-mounted sensor and the tire-mounted sensor determines the road surface condition, an integrated voltage value is corrected based on the information related to the road surface condition. It is thus possible to estimate the road surface condition more accurately. Furthermore, in as much as the road surface condition is estimated at each tire-mounted sensor, the road surface condition can be estimated for each wheel.

Road surface condition estimation device

A road surface state determination device includes a tire-side device and a vehicle-body-side system. The tire-side device is attached to a back surface of a tread of each of a plurality of tires included in a vehicle. The vehicle-body-side system is included in a body of the vehicle. The tire-side device outputs a detection signal corresponding to a magnitude of vibration applied to the tire. The tire-side device generates road surface data indicative of a road surface state appearing in a waveform of the detection signal. The tire-side device transmits the road surface data. The vehicle-body-side system performs bidirectional communication with the tire-side device and receives the road surface data. The vehicle-body-side system determines the road surface state of a road surface on which the vehicle is traveling based on the road surface data.

Road surface state determination device

A collision detection unit corrects a threshold value to a larger value, which a collision check unit uses to compare an output value of a collision detection unit, in case of a rough road surface than in case of a flat road surface. Thus, it becomes possible to suppress erroneous detection on the rough road surface while detecting a collision sensitively on a flat road surface. The rough road is detected by a vibration detection unit provided in a tire side device.

Collision detecting device

In a road surface condition determining device, when determining a road surface condition, a vibration detection unit, a waveform processing unit and a data transmission unit for implementing a sensing function and a data transmission function are not set continuously to an active state for all tire side device, but at least only one tire side device is set to an active state. Remaining one or more is set to a sleep state. A reduction in power consumption of the tire side devices set to the sleep state can thus be achieved. Further, with regard to the at least one tire side device, since the sensing function and the data transmission function remain in the active state, the road surface condition can be reliably determined based on the road surface data of the tire side device.

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Kariya, Japan

Takatoshi Sekizawa