Catalyst activation control system for engines
US6513319B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 2001 |
| Grant date | Feb 4, 2003 |
| Priority date | — |
| Expiry date | Jun 5, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An engine has variable timing mechanisms, which are controlled in starting an engine to set valve opening overlap of an intake valve and an exhaust valve around 30° CA. In this case, internal EGR is actively conducted and fuel burning velocity within a cylinder becomes relatively slow and unburned fuel within the cylinder is emitted to an exhaust pipe to be post-burned by itself. Temperature of exhaust gas is maintained high and catalyst converters in the cold state may be activated quickly by actively implementing the post-burning within the exhaust pipe. Further, ignition timing is retarded, an air-fuel ratio is controlled at a slightly lean ratio and the exhaust valve is advanced. The effect of raising the temperature of exhaust gas by the post-burning may be realized more reliably by combining each of these controls.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.