Mazda Motor Corporation

Kazunori Hirasawa

Masayuki Tetsuno

Masahiro Naito

Yoshitaka Wada

Masanobu Kanno

Takayuki Yamaguchi

Daishi Ikeda

Yoshiaki Tomita

Hiroshi Hayashibara

Kota Matsue

Kaoru Yamada

Takashi Kasai

Tetsuro Furuta

Takashi Tanaka

An exhaust pipe of an engine includes a crank-shaped pipe portion having a first bend and a second bend which guide exhaust gas to a mixer, and a straight pipe portion which is continuous with the second bend. The mixer is arranged in the straight pipe portion. An injector is attached to a portion of the second bend which faces the mixer. The injector has an injection axis which extends in a longitudinal direction of the straight pipe portion so as to point toward the mixer. A guide which guides a part of the exhaust gas from the first bend toward the injector is provided inside the crank-shaped pipe portion.

Exhaust gas purifier for engine

An exhaust emission control system of an engine is provided, which includes a NOcatalyst disposed in an exhaust passage for storing NOwithin exhaust gas when an air-fuel ratio of the exhaust gas is lean, and reducing the stored NOwhen the air-fuel ratio is approximately stoichiometric or rich. A processor executes a NOreduction controlling module for performing, when the NOstored amount exceeds a given amount, a NOreduction control in which a fuel injector performs a post injection of fuel to continuously control the air-fuel ratio to a target ratio so that the stored NOis reduced to be below a given amount, the target air-fuel ratio being a ratio at which the stored NOis reducible, the post injection causing the injected fuel to combust inside a cylinder, the execution of the control permitted when an engine load is within a medium load range.

Exhaust emission control system of engine

Growing community of inventors

Aki-gun, Japan

Kazunori Hirasawa