Catalyst temperature control system for internal combustion engines
US5201173A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 1992 |
| Grant date | Apr 13, 1993 |
| Priority date | — |
| Expiry date | Jan 29, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A catalyst temperature control system is provided for an internal combustion engine having a catalyst arranged in the exhaust system for purifying noxious components in exhaust gases emitted from the engine, and an exhaust gas recirculation passage connected to the intake system and the exhaust system for returning part of the exhaust gases from the exhaust system to the intake system. The temperature of a catalyst bed of the catalyst is detected. An ECU increases a recirculation amount of exhaust gases flowing through the exhaust gas recirculation passage, when the detected temperature of the catalyst bed is higher than a first predetermined value, and enriches the air-fuel ratio of a mixture supplied to the engine. when the detected temperature of the catalyst bed is higher than a second predetermined value upon the lapse of a predetermined time period after the start of increase of the recirculation amount.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.