초록 ▼

A deterioration of a catalytic converter for purifying an exhaust gas produced by burning a mixture of a fuel and air in an internal combustion engine, for example, is judged by supplying the exhaust gas to the catalytic converter, detecting the amount of a predetermined component of the exhaust gas

A deterioration of a catalytic converter for purifying an exhaust gas produced by burning a mixture of a fuel and air in an internal combustion engine, for example, is judged by supplying the exhaust gas to the catalytic converter, detecting the amount of a predetermined component of the exhaust gas which has passed through the catalytic converter with an exhaust gas sensor disposed downstream of the catalytic converter, calculating a target air-fuel ratio for the exhaust gas to be supplied to the catalytic converter for achieving a predetermined emission purifying capability of the catalytic converter based on a detected output signal from the exhaust gas sensor, and judging a deteriorated state of the catalytic converter based on the calculated target air-fuel ratio.

대표청구항 ▼

[ What is claimed is:] [1.] A method of judging a deterioration of a catalytic converter for purifying an exhaust gas produced by burning a mixture of a fuel and air, comprising the steps of:supplying the exhaust gas to the catalytic converter;detecting the amount of a predetermined component of the

[ What is claimed is:] [1.] A method of judging a deterioration of a catalytic converter for purifying an exhaust gas produced by burning a mixture of a fuel and air, comprising the steps of:supplying the exhaust gas to the catalytic converter;detecting the amount of a predetermined component of the exhaust gas which has passed through the catalytic converter with an exhaust gas sensor disposed downstream of the catalytic converter;calculating a target air-fuel ratio for the exhaust gas to be supplied to the catalytic converter for achieving a predetermined emission purifying capability of the catalytic converter based on a detected output signal from said exhaust gas sensor; andjudging a deteriorated state of the catalytic converter based on the calculated target air-fuel ratio. [20.] A method of judging a deterioration of a catalytic converter for purifying an exhaust gas produced by burning a mixture of a fuel and air, comprising the steps of:supplying the exhaust gas to the catalytic converter;detecting the amount of a predetermined component of the exhaust gas which has passed through the catalytic converter with an exhaust gas sensor disposed downstream of the catalytic converter;calculating a target air-fuel ratio for the exhaust gas to be supplied to the catalytic converter for achieving a predetermined emission purifying capability of the catalytic converter based on a detected output signal from said exhaust gas sensor;controlling the air-fuel ratio of the mixture so as to equalize the air-fuel ratio of the exhaust gas supplied to the catalytic converter with said target air-fuel ratio;detecting the air-fuel ratio of the exhaust gas supplied to the catalytic converter while the air-fuel ratio of the mixture is being controlled, with an air-fuel ratio sensor disposed upstream of the catalytic converter; andjudging a deteriorated state of the catalytic converter based on a detected output signal from said air-fuel ratio sensor.