Toyota Jidosha Kabushiki Kaisha

Masahiro Nagae

Hajime Shimizu

Hiroki Murata

Shigeki Nakayama

Tomomi Onishi

Hisashi Ohki

Takashi Koyama

Akira Yamashita

Tomohiro Kaneko

Isao Matsumoto

Tomoyuki Ono

Teruhiko Miyake

Takafumi Yamada

Hiroyuki Haga

Kiyoshi Fujiwara

Kouichi Akita

Seiji Ogura

In a valve drive system, a rocker arm is swung by a cam. An exhaust valve abuts on a first end portion of the rocker arm. A second end portion of the rocker arm is supported by a lash adjuster. The lash adjuster includes a bottomed cylindrical body, a plunger that is contained in the body and that is biased in a direction in which the plunger abuts on the rocker arm, a pooling chamber that is formed in the plunger, a filling chamber that is formed by the plunger and a bottom surface of the body, and a valve body that blocks inflow of oil from the pooling chamber to the filling chamber when the plunger is put in the body. The oil supply to the pooling chamber is stopped when an exhaust throttle valve is closed for actuating an exhaust brake.

Valve drive system of internal combustion engine

An object of the present invention is to control the discharge amount of unburned fuel components in the internal combustion engine. According the present invention, the number of times of execution of sub fuel injection is changed based on the operation range within which the operation state of the internal combustion engine falls so that the lower the engine load of the internal combustion engine is, and the lower the number of engine revolutions of the internal combustion engine is, the more the number of times of execution of sub fuel injection is increased. Furthermore, the lower the atmospheric pressure is, the lower the temperature of the cooling water of the internal combustion engine is, or the lower the temperature of the intake air of the internal combustion engine is, the more an operation range in which the number of times of execution of sub fuel injection is large is expanded to higher loads and higher revolutions.

Fuel injection system of compression ignition internal combustion engine

An object of the present invention is to provide a technology of preventing, in an exhaust gas recirculation system having a low pressure EGR passage that recirculates a part of the exhaust gas from the exhaust passage at some point downstream of the exhaust gas purification apparatus to the intake passage, fragments of the exhaust gas purification apparatus from entering the intake system through the low pressure EGR passage in case that breakage of the exhaust gas purification apparatus occurs. The inventive system has a low pressure EGR valve provided in the low pressure EGR passage, an EGR control unit (S-S) for recirculating exhaust gas to the intake passage by opening the low pressure EGR valve, and a breakage detection unit (S-S) for detecting breakage of the exhaust gas purification apparatus. When breakage of the exhaust gas purification apparatus is detected, the low pressure EGR valve is closed (S).

Exhaust gas recirculation system of internal combustion engine having a purification apparatus breakage detection unit

An EGR system includes a high-pressure EGR unit and a low-pressure EGR unit. During the steady operation of an internal combustion engine, the high-pressure EGR gas and the low-pressure EGR gas are mixed with each other at a mixture ratio, in which the ratio of the high-pressure EGR gas amount to the entire EGR gas amount is higher than that in a known mixture ratio, and then recirculated back to the internal combustion engine. In the engine speed-up transitional operation period, the opening amount of a high-pressure EGR valve is adjusted to the opening amount that is much smaller than the target opening amount corresponding to the target operation mode. Thus, it is possible to suppress occurrence of the situation where the entire EGR gas amount is excessive in the period in which the low-pressure EGR gas amount does not decrease by a sufficient amount.

EGR system for internal combustion engine and method for controlling the same

An exhaust gas recirculation system includes a high-pressure EGR unit; a low-pressure EGR unit; a high-pressure EGR valve; a low-pressure EGR valve; and an EGR control unit that adjusts the opening amount of the high-pressure EGR valve to a required value for achieving the target EGR rate based on the characteristics of the exhaust gas in the low-pressure EGR passage before the operation mode is changed, and that maintains the required value during a period from when the operation mode is changed until when the low-pressure EGR gas is changed to the exhaust gas discharged from the internal combustion engine in the post-change operation mode.

Exhaust gas recirculation system for internal combustion engine and method for controlling the same

A variable-geometry turbocharger and a low-pressure EGR passage are provided. The variable-geometry turbocharger includes a turbine provided in an exhaust passage, and a compressor provided in an intake passage. In the variable-geometry turbocharger, the cross sectional area of a path through which exhaust gas passes is adjusted by adjusting the opening degree of a nozzle vane. The low-pressure EGR passage connects the area of the exhaust passage downstream of the turbine to the area of the intake passage upstream of the compressor. The EGR gas is recirculated to the intake passage through the low-pressure EGR passage. The EGR gas is directed to flow through the low-pressure EGR passage when a vehicle is decelerating or when fuel supply to the internal combustion engine is cut off. The pressure in the intake passage is adjusted toward a target pressure by adjusting the opening degree of the nozzle vane when the EGR gas flows through the low-pressure EGR passage.

Exhaust gas recirculation apparatus for internal combustion engine and method of controlling exhaust gas recirculation apparatus

In an exhaust gas recirculation system for an internal combustion engine, which includes a turbocharger; a high-pressure EGR unit; a low-pressure EGR unit; a high-pressure EGR valve; and a low-pressure EGR valve, first, the opening amount of the high-pressure EGR valve is controlled in a feedback manner, and, then, the opening amount of a low-pressure EGR valve is controlled in a feedback manner in a transitional operation period in which the operation mode of the internal combustion engine is changing. In this way, the intake air amount is promptly adjusted to the target intake air amount without causing hunting.

The ratio between the amount of exhaust gas recirculated by a high-pressure EGR device and the amount of exhaust gas recirculated by a low-pressure EGR device (mixture ratio) is controlled based on the operating state of an internal combustion engine and the correlation between the fuel consumption rate of the internal combustion engine and the mixture ratio. Thus, high-pressure EGR and low-pressure EGR are performed at the mixture ratio (optimum mixture ratio) at which the fuel consumption rate is at or around the minimum value.

Exhaust gas control system for internal combustion engine

An exhaust gas recirculation device includes a turbocharger () having a turbine () on an exhaust pipe () and a compressor () on an intake pipe (), a low-pressure EGR passage () connecting the exhaust pipe () downstream of the turbine () and the intake pipe () upstream of the compressor (), and a filter () provided on the exhaust pipe () downstream of the turbine (). In the device, an exhaust throttle valve () is disposed on the exhaust pipe () that is downstream of the filter () and that is upstream of a site of connection with the low-pressure EGR passage ().

Exhaust gas recirculation device of internal combustion engine, and control method thereof

A variable-nozzle type turbo charger capable of temporarily decreasing the back pressure of the engine at the start of the engine. The turbo charger is equipped with a plurality of nozzle vanes of which the opening degree can be changed and are capable of changing the areas of turbine nozzles at the time when exhaust gases of an engine are guided from said turbine nozzles formed among said nozzle vanes to a turbine rotor, wherein an actuator that adjusts the opening degree of the nozzle vanes is so controlled that the areas of the turbine nozzles are larger than a minimum area for a predetermined period of time from the start of the engine, and, after the passage of said predetermined period of time, said actuator is so controlled that the areas of said turbine nozzles become the minimum area to promote the warming-up of the engine when the water temperature of the engine or the engine load is smaller than a predetermined value.

Growing community of inventors

Nishikamo-gun, Japan

Masahiro Nagae