Toyota Jidosha Kabushiki Kaisha

Yusuke Kawamura

Hiroshi Sawada

Yasushi Iwazaki

Takashi Nakamura

Shinya Kondo

Takuya Matsumoto

Makoto Sato

Toru Kidokoro

Naoki Takahashi

Takahiko Fujiwara

Masahiko Takeuchi

Tadashi Suzuki

Keizo Hiraku

Koji Umezawa

Takeho Aisaka

Akemi Satou

Takahiro Fujiwara

A map creation unit that creates a driving diagnostic map used by the driving diagnostic unit for driving diagnosis of the vehicle based on a detection value of vehicle information acquired by a sensor provided in the vehicle, and a map management unit that discards the driving diagnostic map when a discarding condition is satisfied with respect to the driving diagnostic map and the latest detection value created by the map creation unit based on the detection value acquired before the latest detection value which is the latest detection value.

Driving diagnostic map creation device, driving diagnostic map creation system, and driving diagnostic map creation method

A vehicle behavior estimation system includes: a yaw rate sensor that detects a yaw rate of a diagnosis target vehicle; a vehicle speed sensor that detects a vehicle speed of the diagnosis target vehicle; and a processor. The processor acquires a first curvature that is a curvature of a traveling locus of the diagnosis target vehicle based on the yaw rate and the vehicle speed, and performs a driving diagnosis related to steering of the diagnosis target vehicle based on a criterion and a curvature-related value. The criterion defines a relationship between a steering angle-related value that is a value based on a steering angle of a steering wheel of a reference vehicle that is a vehicle different from the diagnosis target vehicle and a behavior of the reference vehicle caused by steering. The curvature-related value is a value based on the first curvature.

Vehicle behavior estimation system and vehicle behavior estimation method

A secondary air supply device for an internal combustion engine, the secondary air supply device includes a secondary air supply passage, an air pump, a control valve, a pressure sensor and an electronic control unit. The electronic control unit is configured to: (a) when the control valve is opened so that the secondary air supply passage is opened and the air pump is driven, control the air pump to maintain driving of the air pump and control the control valve to close so as to close the secondary air supply passage; (b) calculate a differential pressure between a maximum pressure and a convergence pressure of the pressures within the secondary air supply passage since just after the secondary air supply passage is closed; and (c) calculate a flow amount of secondary air supplied from the secondary air supply passage supplied to the exhaust gas passage based on the differential pressure.

Secondary air supply device for internal combustion engine

A secondary air supply system includes an electric air pump that supplies secondary air to a location upstream of an exhaust gas purification catalyst arranged in an exhaust passage; a control valve that opens/closes a secondary air supply passage; a pressure detector that detects a pressure between the pump and the control valve; and a control unit that detects a first pressure in a first operating state where the control valve is closed, and detects a second pressure in a second operating state where the control valve is open, using the pressure detector. The control unit corrects at least one of the first and second pressures based on a first driving voltage for the pump in the first operating state and a second driving voltage in the second operating state, and estimates a secondary air flow rate based on the first and second pressures after correction.

Secondary air supply system for internal combustion engine

An electronic control device calculates the maximum actual oxygen storage capacity of a catalyst. The gradient of a linear expression formed between the catalyst temperature and the maximum oxygen storage capacity of the catalyst is stored for each degradation level of the catalyst. The gradient can be learned in accordance with the same temperature of the catalyst and the maximum actual oxygen storage capacity. When the maximum actual oxygen storage capacity is calculated, it is revised in accordance with the temperature of the catalyst, a reference temperature, the linear expression, and the learned gradient. The revised maximum oxygen storage capacity which is the maximum oxygen storage capacity when the temperature of the catalyst during the same calculation period is equal to the reference temperature is then calculated. If a response delay is detected in the output of an oxygen sensor, the gradient of the learned linear expression is discarded.

Device for purifying exhaust gas of internal combustion engine

The fact that 'with respect to a process in which the output value of a downstream air-fuel ratio sensor (sensor output value) is inverted from the minimum output value to the maximum output value during execution of an active control, the local maximum and minimum values of the secondary differential value of the sensor output value is widely affected by the size of the response delay of the downstream air-fuel ratio sensor and the size of the degree of the degradation of the three-way catalyst' is utilized. By preliminarily acquiring and memorizing, as maps, these relations obtained through an experiment, and applying the 'local maximum and minimum values of the secondary differential value of the sensor output value' calculated from the transition of the sensor output value acquired during execution of the active control to the maps, the response delay (time constant) of the downstream air-fuel ratio sensor is acquired.

Apparatus for acquiring responsibility of oxygen concentration sensor

An exhaust gas purification catalyst includes: a lower catalyst layer that contains a ceria-zirconia mixed oxide having 50 to 70 mass % of CeOand 5 mass % or more of PrOand carries at least one of Pt and Pd; and an upper catalyst layer that contains at least zirconia and carries at least Rh, wherein the total amount of CeOper liter of the carrier base is 15 to 30 g. Because the amount of CeOis small, formation of HS is suppressed and a high capability of adsorbing and releasing oxygen is brought out in spite of the small amount of CeO.

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Susono, Japan

Yusuke Kawamura