Honda Motor Co., Ltd.

Shinichiro Otsuka

Noritaka Masumitsu

Ryoko Yamada

Kenji Katayama

An exhaust purification system includes an LAF sensor provided in an exhaust pipe and generates a signal corresponding to an air-fuel ratio of exhaust gas. An upstream catalytic converter is downstream of the LAF sensor and has a catalyst to purify the exhaust gas. An O2 sensor is downstream of the upstream catalytic converter, and generates a signal corresponding to the air-fuel ratio of the exhaust gas. A GPF is downstream of a the O2 sensor and purifies the exhaust gas. An ECU controls an air-fuel mixture in an engine using output signal KACT of the LAF sensor and an output signal VOof the O2 sensor such that the air-fuel ratio of exhaust gas flowing into the GPF converges to a target value near the stoichiometric ratio. The GPF has a filter substrate and a downstream TWC supported by a partition of the filter substrate.

Exhaust purification system of internal combustion engine

Provided is a GPF capable of exhibiting better than conventional three-way purification function. A gasoline particulate filter (GPF) that is provided in an exhaust pipe of an engine and that performs purification by capturing particulate matter (PM) in exhaust gas is provided with a filter substrate in which a plurality of cells extending from an exhaust gas inflow-side end face to an outflow-side end face are defined by porous partition walls and in which openings at the inflow-side end face and openings at the outflow-side end face of the cells are alternately sealed; and a three-way catalyst (TWC) supported by the partition wall. The three-way catalyst is the GPF comprising a catalytic metal containing at least Rh, and a composite oxide having an oxygen storage capacity and containing Nd and Pr in a crystal structure.

Exhaust purification filter

An exhaust purification system includes an LAF sensor provided in an exhaust pipe and generates a signal corresponding to an air-fuel ratio of exhaust gas. An upstream catalytic converter is downstream of the LAF sensor and has a catalyst to purify the exhaust gas. An O2 sensor is downstream of the upstream catalytic converter, and generates a signal corresponding to the air-fuel ratio of the exhaust gas. A GPF is downstream of a the O2 sensor and purifies the exhaust gas. An ECU controls an air-fuel mixture in an engine using output signal KACT of the LAF sensor and an output signal VO2 of the O2 sensor such that the air-fuel ratio of exhaust gas flowing into the GPF converges to a target value near the stoichiometric ratio. The GPF has a filter substrate and a downstream TWC supported by a partition of the filter substrate.

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Wako, Japan

Shinichiro Otsuka