Denso Corporation

Denso Corpora Tion

Ryosuke Kanbayashi

Masashi Mori

Takatoshi Sekizawa

Nobuya Watabe

Yoichiro Suzuki

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 road surface state determination apparatus includes a plurality of tire-side devices each of which detects vibration applied to corresponding tire and produces road surface data indicative of a road surface state based on data of the vibration, and a vehicle-body-side system that determines the road surface state based on the road surface data.

Road surface state determination apparatus

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 system includes a tire side device that is arranged corresponding to a tire provided in a vehicle and transmits data related to the tire, and a wear estimation unit that estimates a tire wear state based on the data related to the tire. The tire side device holds data related to an elapsed time since the tire was manufactured as data related to the tire, transmits data related to the elapsed time to the wear estimation unit. The wear estimation unit estimates the tire wear state based on the mileage from the start of use of the tire and a tire deterioration degree indicated by the data related to the elapsed time.

Tire system

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 condition assessing device includes: a tire-mounted device; and a vehicle body system. The tire-mounted device includes: a vibration detector that outputs a detection signal of a vibration on a tire; a waveform processor that generates the road surface data; and a first data communication unit. The vehicle body system includes: a second data communication unit; and a road surface evaluation unit that evaluates the road surface condition. The tire-mounted device transmits an advertise signal including the road surface data indicative of a result of a waveform process on the detection signal and a waveform processing value corresponding to the road surface condition. The vehicle body system evaluates the road surface condition based on the waveform processing value.

Road surface condition assessing device

A control unit of a tire-mounted sensor determines whether a tire has been exchanged. When the tire has been exchanged, the control unit changes the threshold value of a road surface state determination condition used for detecting the road surface state from vibration data of the tire detected by an acceleration sensor of the tire-mounted sensor. For example, the threshold value of the road surface state determination condition is reset upon determining that the tire has been exchanged, by transmitting an instruction to the tire-mounted sensor through a tool at an automobile maintenance shop, etc.

Road surface state estimation device

A condition in which an abnormality can occur in a tire is accurately detected on the basis of a detection signal from an acceleration sensor used to detect a road surface state and a possibility that an abnormality has occurred in the tire is also detected. In addition, the detection result is stored as a diagnosis history. The diagnosis history or the possibility that an abnormality has occurred in the tire are notified through a notification device in a vehicle body side system so that a user is informed in advance of the possibility that an abnormality has occurred in the tire. In addition, when the diagnosis history is checked through a tool in a car repair shop, etc., the diagnosis history stored in a tire-mounted sensor is read out. Accordingly, the possibility of abnormality of the tire can be informed also in the car repair shop, etc.

Tire-mounted sensor, diagnosis history memory device and diagnosis notification device

A tire-mounted sensor includes a vibration detector, an acceleration sensor, a signal processor, and a transmitter. The vibration detector outputs a detection signal according to amplitude of a vibration of the tire. The acceleration outputs a detection signal according to an acceleration of the tire in a radial direction. The signal processor detects a rotational angle of the tire reaching a ground angle during each rotation of the tire, sets a measurement period including a time period during which the rotational angle of the tire is at the ground angle, extracts a ground contact section during which the portion of the tread provided with the vibration sensor is in contact with the ground, in the measurement period, and generates a road surface data based on the detection signal output from the vibration detector during the ground contact section. The transmitter transmits the road surface data.

Tire-mounted sensor and road surface condition estimation apparatus including the same

A tire-mounted sensor is mounted to a rear surface of a tread of a tire. the tire-mounted sensor includes: a vibration detector, a signal processor, a transmitter, and an activation controller. The vibration detector outputs a detection signal according to amplitude of a vibration of the tire. The signal processor extracts a ground contact section during which the portion of the tread provided with the vibration sensor is in contact with the ground, from the detection signal, and generates a road surface data based on the detection signal during the ground contact section. The transmitter transmits the road surface data. The activation controller starts an activation of the signal processor at a time in association with the ground contact starting time at which the portion of the tread provided with the vibration detector begins to be in contact with the ground.

In a tire-mounted sensor attached to a tire, the rotation direction of which is predetermined with respect to the direction of forward movement, a left/right determination as to which of a right wheel or a left wheel has the tire-mounted sensor attached thereto is made on the basis of a detection signal of an acceleration sensor. The result of left/right determination is transmitted to a receiver. In this way, without requesting an operator's manual operation or equipment for bidirectional communication, which of the right wheel or the left wheel has the tire-mounted sensor attached thereto can be determined.

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Kariya, Japan

Ryosuke Kanbayashi