US 2021/0215113 A1 · CATALYST DETERIORATION JUDGING DEVICE FOR INTERNAL COMBUSTION ENGINE

Abstract

In order to detect the degree of deterioration of one catalyst with a simple configuration, a catalyst deterioration judging device for an internal combustion engine includes an upstream catalyst disposed in an engine exhaust passage, a downstream catalyst disposed in the engine exhaust passage downstream of the upstream catalyst, an inflow air-fuel ratio sensor for detecting the air-fuel ratio of an inflow exhaust gas to the upstream catalyst, an outflow air-fuel ratio sensor for detecting the air-fuel ratio of an outflow exhaust gas from the downstream catalyst, and an electronic control unit. The maximum oxygen storage amount of the upstream catalyst is detected based on the output of the inflow air-fuel ratio sensor and the output of the outflow air-fuel ratio sensor when the upstream catalyst is in the active state and the downstream catalyst is in the inactive state.

Claims14

Dependent claims

A catalyst deterioration judging device for an internal combustion engine, comprising:

a catalyst including a first catalyst and a second catalyst arranged in series in an engine exhaust passage;
an inflow exhaust gas detector configured to detect a state quantity of an inflow exhaust gas to the catalyst;
an outflow exhaust gas detector configured to detect a state quantity of an outflow exhaust gas from the catalyst;
and
an electronic control unit configured to detect a degree of deterioration of the first catalyst based on an output of the inflow exhaust gas detector and an output of the outflow exhaust gas detector when the first catalyst is in an active state and the second catalyst is in an inactive state.

2 more elements

A catalyst deterioration judging method of an internal combustion engine which is provided with a catalyst including a first catalyst and a second catalyst arranged in series in an engine exhaust passage, the catalyst deterioration judging method comprising:

detecting a state quantity of an inflow exhaust gas flowing into the catalyst;
detecting a state quantity of an outflow exhaust gas flowing out from the catalyst;
and
detecting a degree of deterioration of the first catalyst based on the state quantity of the inflow exhaust gas and the state quantity of the outflow exhaust gas when the first catalyst is in an active state and the second catalyst is in an inactive state.

1 more element

Dependencies are inferred from the claim text.

Catalyst deterioration judging device for internal combustion engine

Life of this patent

Catalyst deterioration judging device for internal combustion engine

Life of this patent

Abstract

Claims14