초록 ▼

An exhaust-gas temperature raising system, installed in an in-cylinder injection type internal combustion engine adapted to spark-ignite fuel injected from a fuel injection valve directly into a combustion chamber, includes an electronic control unit which controls the fuel injection valve to inject

An exhaust-gas temperature raising system, installed in an in-cylinder injection type internal combustion engine adapted to spark-ignite fuel injected from a fuel injection valve directly into a combustion chamber, includes an electronic control unit which controls the fuel injection valve to inject the fuel, at a delayed fuel-injection timing in a compression stroke of the engine, in such an amount as to form an overrich air-fuel mixture locally around an ignition plug together with air in the combustion chamber, when the engine is in an operating condition in which an exhaust-gas temperature is required to rise. The electronic control unit controls an engine control parameter so that the fuel injected at the delayed fuel-injection timing and spark-ignited is insufficiently combusted around the ignition plug, and is then mixed with extra oxygen in the combustion chamber so as to be combusted while being affected by a gas flow in the combustion chamber, whereby the exhaust-gas temperature is effectively raised while suppressing the fuel consumption rate to a minimum.

대표청구항 ▼

[ What is claimed is:] [1.] An exhaust-gas temperature raising system for an in-cylinder injection type internal combustion engine in which fuel injected from a fuel injection valve directly into a combustion chamber is spark-ignited for stratified combustion, comprising:engine operating condition d

[ What is claimed is:] [1.] An exhaust-gas temperature raising system for an in-cylinder injection type internal combustion engine in which fuel injected from a fuel injection valve directly into a combustion chamber is spark-ignited for stratified combustion, comprising:engine operating condition detecting means for detecting an operating condition of the engine, in which an exhaust-gas temperature is required to rise, to raise a temperature of a catalyst;fuel injection control means for controlling the fuel injection valve to inject the fuel, in a compression stroke of the engine, in such an amount as to form an over-rich air-fuel mixture locally around an ignition plug together with air in the combustion chamber, when the engine is in the operating condition in which the exhaust-gas temperature is required to raise; andengine control means for controlling an engine control parameter so that the fuel injected in the compression stroke and spark-ignited is insufficiently combusted around the ignition plug, and is then mixed with extra oxygen in the combustion chamber such that the insufficiently combusted fuel is combusted while being affected by a gas flow in the combustion chamber, when a control of the fuel injection valve is carried out by said fuel injection control means.