Toyota Jidosha Kabushiki Kaisha

Shinichi Nakagoshi

Akihiro Katayama

Isao Nakajima

Masahide Okada

Leuth Insixiengmai

Sei Maruta

Kazuhiro Akisada

Shinji Yoshioka

Masashi Hakariya

Yoshihisa Oda

Hiromasa Hashimoto

Toshihiro Kato

Tatsuro Shimada

Kiyotaka Kushihama

An engine control device is configured to perform an air-fuel ratio main feedback process based on an output of a front air-fuel ratio sensor, an air-fuel ratio sub feedback process of alternately switching a target air-fuel ratio between a rich side target air-fuel ratio and a lean side target air-fuel ratio based on an output of a rear air-fuel ratio sensor, and a catalyst air-fuel ratio correction process of, when an opening degree of a wastegate valve is large, correcting the target air-fuel ratio to be the air-fuel ratio on the rich side with respect to the air-fuel ratio when the opening degree is small.

Engine control device

An engine control device performs air-fuel ratio control of an engine through a main air-fuel ratio feedback process based on an output of a front air-fuel ratio sensor, a sub air-fuel ratio feedback process of alternately switching a target air-fuel ratio between a lean-side target air-fuel ratio and a rich-side target air-fuel ratio based on an output from a rear air-fuel ratio sensor. The engine control device performs a limiting process of setting an upper limit of a control range of an opening level of a waste gate valve to be less when a combustion operation of the engine continues to be performed for a long time without being stopped by fuel cutoff than otherwise.

An exhaust gas purification apparatus for an internal combustion engine includes a particulate filter, an air fuel ratio sensor to detect an air fuel ratio of exhaust gas at the downstream side of the filter, and a controller configured to: change an air fuel ratio, determine whether an amount of particulate matter (PM) deposited in an interior of a partition wall of the filter is equal to or smaller than a predetermined amount, and estimate a maximum storable oxygen amount of the catalyst from a change of the air fuel ratio of exhaust gas at the time when the air fuel ratio of the exhaust gas is changed, in cases where the amount of PM deposited in the interior of the partition wall of the filter is equal to or smaller than the predetermined amount.

Exhaust gas purification apparatus for an internal combustion engine

An apparatus for detecting imbalance abnormality in an air-fuel ratio between cylinders in a multi-cylinder internal combustion engine is disclosed. The apparatus includes an imbalance determining unit programmed to determine imbalance in an air-fuel ratio of a first cylinder belonging to a cylinder group based upon a difference value between an index value correlative with a crank angular speed detected in the first cylinder and an index value correlative with a crank angular speed detected in a second cylinder belonging to another cylinder group, and further a correction unit programmed to correct the difference value for the first cylinder based upon the index value detected in at least one of other cylinders belonging to the same cylinder group as that of the first cylinder.

Apparatus for detecting imbalance abnormality in air-fuel ratio between cylinders in multi-cylinder internal combustion engine

An inter-cylinder air-fuel ratio variation abnormality detection apparatus is disclosed. The apparatus determines imbalance of an air-fuel ratio among the cylinders based on a difference between index values correlated with crank angular velocities detected in a set of opposite cylinders belonging to different banks and having crank angles different from one another by 360&#xb0;; and carries out an air-fuel ratio feedback process for controlling an amount of injected fuel for each of the banks, wherein the apparatus comprises a correction unit correcting, before determining the air-fuel ratio imbalance, the difference between the index values in a direction of combustion improvement for opposite cylinders that are opposite to cylinders belonging to a bank identical to a bank of a cylinder with the most deviating index value from a standard value among all the cylinders and being other than the cylinder with the most deviating index value.

Inter-cylinder air-fuel ratio variation abnormality detection apparatus for multicylinder internal combustion engine

In an engine having a plurality of cylinders in which a plurality of fuel injection valves are provided respectively, fuel is injected at a predetermined injection ratio, and an abnormality of air-fuel ratio variation is detected. If a fuel injection amount of at least one of the plurality of the fuel injection valves is smaller than a predetermined reference value, the fuel injection amount is increased so as to become equal to or larger than the reference value.

Growing community of inventors

Miyoshi, Japan

Shinichi Nakagoshi