Honda Giken Kogyo Kabushiki Kaisha

Honda Giken Kogyo Kabushiki Kabushiki Kaisha

Yoshiaki Matsuzono

Sachito Fujimoto

Hideo Moriwaki

Masahiro Sakanushi

Akira Hashimoto

Satoshi Kiso

Hiroshi Oono

Norihiko Suzuki

Yuji Fujiki

Shinichi Kikuchi

Ryoko Yamada

Hideki Uedahira

Gaku Hatano

Hideki Uedahra

Hisato Shimizu

An exhaust emission control system for an internal combustion engine is provided. The exhaust emission control system () includes a monolith catalyst (MC) that includes an oxygen storage agent and a noble metal-based three-way catalyst including Pd, Rh, and Pt disposed at an upstream location in the exhaust gas flow in the internal combustion engine (), and a perovskite-type double oxide having a three-way catalytic function disposed at a downstream location in the exhaust gas flow. The amount C1 of Pd carried is 0.97 g/L&#x2266;C1&#x2266;1.68 g/L, the amount C2 of Rh carried is 0.11 g/L&#x2266;C2&#x2266;0.2 g/L, the amount C3 of Pt carried is 0.06 g/L&#x2266;C3&#x2266;0.11 g/L, the amount C4 of the oxygen storage agent carried is 25 g/L&#x2266;C4&#x2266;75 g/L, and the amount C5 of the perovskite-type double oxide carried is 5 g/L&#x2266;C5&#x2266;15 g/L. It is thereby possible to provide an exhaust emission control system that can reduce the production cost by reducing the amount of noble metal-based three-way catalyst used and at the same time can maintain a high exhaust emission control rate.

Device for clarifying exhaust gas from internal combustion engine

The invention provides a catalyst deterioration detecting system that is capable of detecting the degree of deterioration of each catalyst in a catalyst converter which includes two or more catalysts in series. The catalyst deterioration detecting system of an internal-combustion engine according to the invention is provided with a upstream catalyst located on an upstream side of an exhaust system of the internal-combustion engine and a downstream catalyst located on a downstream side of the exhaust system. The device comprises an oxygen density detector which is disposed downstream of the downstream catalyst and a deterioration detector for detecting a deterioration degree of the upstream catalyst based on the output of the oxygen density detector. According to an aspect of the invention, the deterioration detector detects deterioration degree of the downstream catalyst based on the previously detected deterioration degree of the upstream catalyst.

Catalyst deterioration detecting system for an automobile

A catalyst deterioration-determining system for an internal combustion engine has a catalyst arranged in the exhaust system, for purifying exhaust gases emitted from the engine, an oxygen concentration sensor arranged in the exhaust system at a location downstream of the catalyst, for detecting the concentration of oxygen present in the exhaust gases, and an ECU which controls the air-fuel ratio of an air-fuel mixture supplied to the engine in a feedback manner in response to the output from the oxygen concentration sensor. Determination of deterioration of the catalyst is carried out based on the output from the oxygen concentration sensor during execution of air-fuel ratio feedback control. An inversion period parameter representative of a repetition period of change in the output from the oxygen concentration sensor over a predetermined diagnosis period is measured, and a determination parameter is calculated by averaging values of the inversion period parameter measured over different diagnosis periods as the predetermined diagnosis period. The determination of deterioration of the catalyst is carried out based on the determination parameter.

Catalyst deterioration-determining system for internal combustion engines

An evaporative fuel-processing system for an internal combustion engine has an evaporative emission control system. An ECU carries out negative pressurization of the interior of the evaporative emission control system, by opening a purge control valve and closing a vent shut valve, and determines presence/absence of leakage from the evaporative emission control system, based on a rate of decrease in negative pressure within the system, by closing a purge control valve. Before the negative pressurization, the interior of the evaporative emission control system is opened to the atmosphere, and during the open-to-atmosphere, a pressure state within the fuel tank is estimated based on a rate of change in an output from a pressure sensor which senses pressure within the evaporative emission control system. The ECU determines whether the evaporative emission control system is normal, based on the estimated pressure state.

Evaporative fuel-processing system for internal combustion engines

An evaporative fuel-processing system for an internal combustion engine has an evaporative emission control system and a pressure sensor. An ECU carries out negative pressurization of the interior of the evaporative emission control system, by opening a purge control valve and closing a vent shut valve. The purge control valve is closed over a predetermined time period after the interior of the evaporative emission control system is brought into the predetermined negatively pressurized state, and a rate of decrease in negative pressure within the evaporative emission control system is detected. Then, it is determined whether or not there is leakage from the evaporative emission control system, based on the detected rate of decrease in the negative pressure, and at least one detected pressure value at at least one predetermined time point within the predetermined time period over which the purge control valve is closed.

Growing community of inventors

Wako, Japan

Yoshiaki Matsuzono