Combustion state-determining system and combustion state control system for internal combustion engines
AssigneeHonda Giken Kogyo Kabushiki Kaisha
InventorsShigetaka Kuroda, Kazutomo Sawamura, Masayoshi Yamanaka
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Abstract
A combustion state-determining system for an internal combustion engine has an ECU which determines a misfiring state of the engine, and calculates a misfiring rate of the engine, based on the result of the determination of the misfiring state. A catalyst temperature sensor detects the temperature of a catalytic converter as the exhaust system temperature, and the ECU determines the combustion state of the engine, based on the detected exhaust system temperature and the calculated misfiring rate. A combustion state control system restrains the output from the engine, based on the determination result of the combustion state-determining system.
Claims7
In a combustion state-determining system for an internal combustion engine having an exhaust system, and a catalytic converter arranged in said exhaust system, for purifying exhaust gases emitted from said engine, said combustion state-determining system including misfire-determining means for determining a misfiring state of said engine, and misfiring rate-calculating means for calculating a misfiring rate of said engine, based on a determination result of said misfire-determining means, the improvement comprising:
- temperature-detecting means for detecting a temperature of said exhaust system of said engine;
- and
- combustion state-determining means for determining a combustion state of said engine, based on the temperature of said exhaust system detected by said temperature-detecting means and said misfiring rate calculated by said misfiring rate-calculating means, wherein when the misfiring rate is below a first predetermined value, said combustion state-determining means determines that the combustion state of said engine is normal if the temperature of said exhaust system is below a predetermined value, and when the misfiring rate exceeds said first predetermined value, said combustion state-determining means determines that the combustion state of said engine is in a first misfiring state which causes an adverse effect on component parts of said exhaust system if the misfiring rate exceeds a second predetermined value which decreases as the temperature of said exhaust system increases, and the combustion state of said engine is in a second misfiring state which causes degradation of exhaust emission characteristics of said engine if the misfiring rate is below said second predetermined value.
In a combustion state control system for an internal combustion engine having an exhaust system, and a catalytic converter arranged in said exhaust system, for purifying exhaust gases emitted from said engine, said combustion state control system including misfire-determining means for determining a misfiring state of said engine, and misfiring rate-calculating state of said engine, and misfiring rate-calculating means for calculating a misfiring rate of said engine, based on a determination result of said misfire-determining means, the improvement comprising:
- temperature-detecting means for detecting a temperature of said exhaust system of said engine;
- combustion state-determining means for determining a combustion state of said engine, based on the temperature of said exhaust system detected by said temperature-detecting means and said misfiring rate calculated by said misfiring rate-calculating means;
- and
- output-restraining means for restraining an output from said engine, depending on a determination result of said combustion state-determining means,
- wherein when the misfiring rate is below a first predetermined value, said combustion state-determining means determines that the combustion state of said engine is normal if the temperature of said exhaust system is below a predetermined value, and when the misfiring rate exceeds said first predetermined value, said combustion state-determining means determines that the combustion state of said engine is in a first misfiring state which causes an adverse effect on component parts of said exhaust system if the misfiring rate exceeds a second predetermined value which decreases as the temperature of said exhaust system increases, and the combustion state of said engine is in a second misfiring state which causes degradation of exhaust emission characteristics of said engine if the misfiring rate is below said second predetermined value, said output-restraining means restraining the output from said engine when said combustion state-determining means determines that the combustion state of said engine is in said first misfiring state.
Dependencies are inferred from the claim text.