Toyota Jidosha Kabushiki Kaisha

Yamaha Hatsudoki Kabushiki Kaisha

Nippon Thermostat Co., Ltd.

Denso Corporation

Hiroyasu Koyama

Kenji Kimura

Shigemasa Hirooka

Kaoru Ohtsuka

Yasuhiro Oi

Fujio Inoue

Takeo Ogiso

Keita Nakanishi

Takayuki Demura

Shinya Kondo

Tetsuji Nagata

Daisuke Tsukamoto

Shinya Kondou

Ryohei Muramoto

A coolant passage deviceincludes coolant intake pipesandthat take in coolant from an engine, a delivery pipeto a radiator communicating with the coolant intake pipes, and a delivery pipeto the heater core branched from a central passageconnecting the coolant intake pipes with the delivery pipe to the radiator. A branch portleading to the delivery pipeto the heater core is opened in an upper portion in the central passagein a state where the coolant passage deviceis mounted to the engine, and the branch porthas a wall surfacesurrounding the branch port and hanging down into the central passage. The wall surfaceprevents bubbles contained in the coolant from entering the branch port. And the coolant passage device consequently prevents coolant flow noise from occurring.

Coolant passage device for internal combustion engine

A cylinder block includes a first bank, a second bank, and a press-fitting portion. The first bank and the second bank are arranged in positions offset from each other in a cylinder arrangement direction. The press-fitting portion is provided straddling a first end surface of the first bank and a second end surface of the second bank. The press-fitting portion has a hole. The first end surface protrudes in a direction in which the press-fitting portion protrudes in the cylinder arrangement direction, with respect to the second end surface. A thickness of the press-fitting portion in a radial direction of the hole at a first portion that is connected to the first end surface is thinner than a thickness of the press-fitting portion in the radial direction of the hole at a second portion that is connected to the second end surface.

Cylinder block

A pair of coolant receiving pipes () and () for respectively receiving a coolant from left and right engine heads of a V-engine are provided on a first body () side, and a collecting passage () for collecting the coolant, communication opening () towards a radiator via the above-mentioned collecting passage () and communication opening () towards a branch passage provided with a heater core part or the like are provided on a second body () side and these are individually resin molded. A coolant passage apparatus () is formed by joining the above-mentioned first body () and second body () for example by welding means.

Coolant passage apparatus for internal combustion engine

When an air pump is operated, a brush temperature increase rate stored in an ECU in relation to a discharge pressure of the air pump and a brush temperature is multiplied by a calculation cycle time, and the resultant value is cumulatively added. When the air pump is stopped, a brush temperature decrease rate stored in the ECU in relation to the brush temperature is multiplied by the calculation cycle time, and the resultant value is cumulatively added. Each of the cumulative values read from a map is added to and subtracted from an initial brush temperature value, respectively so as to estimate the brush temperature.

Electric air pump for secondary air supply system

There is provided a device for supplying secondary air, which comprises a secondary air passage for supplying secondary air, to an exhaust passage of an engine, upstream of an exhaust purification device provided in the exhaust passage, a pump provided in the secondary air passage for supplying a secondary air, a battery used for driving the pump, at least one opening-closing device for opening and closing the secondary air passage, and a pressure sensor provided between the pump and the opening-closing device for detecting a pressure in the secondary air passage. A malfunction of at least one of the pump and the opening-closing device is detected on the basis of at least one of the pressures detected when the secondary air passage is opens and when the secondary air passage is closed. The malfunction detection is ceased when the voltage of the battery changes by a value larger than a predetermined value when the pressure sensor detects a malfunction of the pressure variation in the secondary air passage for detecting a malfunction of at least one of the pump and the opening-closing device.

Device for supplying secondary air

In a secondary air supply system, each of two branch portions of a secondary air supply pipe that is divided from a joint portion is provided with an air control valve, and the joint portion is provided with a pressure sensor and an auxiliary air control valve. The air control valves are opened at different timings such that pressure fluctuations in the joint portion upon opening of the firstly and the secondly opened air control valves are measured. An abnormality diagnosis is performed with respect to those two air control valves based on combinations of the aforementioned two pressure fluctuations.

Secondary air supply system and abnormality diagnosis method of secondary air supply system

An anomaly judgment apparatus for a secondary air supply system which includes a secondary air supply path for introducing secondary air into an exhaust path of an internal combustion engine and an open-close valve disposed in the secondary air supply path. The valve is opened and/or closed by drive force of negative pressure introduced from a portion of an intake path of the engine downstream of a throttle valve. The anomaly judgment apparatus includes an anomaly judgment section for judging whether or not the secondary air supply system is anomalous; a negative pressure judgment section for judging whether or not the negative pressure is secured to a degree required for the drive force to reliably open and/or close the open-close valve; and an anomaly judgment prohibition section for prohibiting judgment by the anomaly judgment section when the negative pressure is not secured to the required degree.

Anomaly judgment apparatus for secondary air supply system

An anomaly judgment apparatus for a secondary air supply system which includes a secondary air supply path for introducing secondary air from an intake path of an engine into an exhaust path at a location upstream of a catalytic converter disposed in the exhaust path. The apparatus includes a pressure detector for detecting pressure in the secondary air supply path, and an anomaly judgment section for calculating pulsation level indicative of the degree of pulsation of pressure detected by the pressure detector and for judging, on the basis of at least the pulsation level, whether or not the secondary air supply system is anomalous. The apparatus further includes an anomaly judgment prohibiting section for prohibiting judgment by the anomaly judgment section when the degree of propagation of intake air pulsation arising in the intake path into the secondary air supply path is equal to or higher than a predetermined level.

An exhaust gas purifying apparatus adopted to an internal combustion engine provided with air-fuel ratio learning means for learning a primary air-fuel ratio given in the form of a mass ratio between air and fuel introduced into a combustion chamber, comprises an exhaust gas purifying catalyst provided in an exhaust gas passage of the engine and a catalyst activating means for supplying secondary air to an upstream of the exhaust gas purifying catalyst and increasing the quantity of fuel supplied to the engine to activate the exhaust gas purifying catalyst. The apparatus further comprises air-fuel ratio learning determining means for, when the internal combustion engine is started, determining whether or not learning of the primary air-fuel ratio by the air-fuel ratio learning means is completed; and activation control means for, when determined that the learning of the primary air-fuel ratio is not completed, prohibiting supply of the secondary air and increase of the quantity of fuel by the catalyst activation means.

Exhaust gas purifying apparatus of internal combustion engine and activation control method for the same

The invention controls the opening of an oil control valve (OCV), which controls the operation of a variable valve timing mechanism in an internal combustion engine, according to a duty ratio of a driving pulse signal. An electronic control unit (ECU) performs feedback control on a duty ratio DR of the driving pulse signal during ordinary operation based on a target value and an actual value of the valve timing. When the oil temperature is low (i.e., when the operating oil viscosity is high), the ECU controls the valve timing of the engine by repeating an inching operation that maintains the duty ratio DR of the signal at a large value (i.e., 0% or 100%) for a predetermined hold time so as to operate the variable valve timing mechanism, and then maintaining the duty ratio DR of the signal at a value (50%) that does not operate the variable valve timing mechanism.

Growing community of inventors

Mishima, Japan

Hiroyasu Koyama