Secondary air supply for internal combustion engine
US4617891A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 1984 |
| Grant date | Oct 21, 1986 |
| Priority date | — |
| Expiry date | Sep 4, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A secondary air intake system is used in an internal combustion engine. The system supplies secondary air through a first and a second secondary air passage. The first secondary air passage includes a first vacuum operated air control valve. A vacuum control which includes an electrically operated vacuum control valve operates the first vacuum operated air control valve to vary the effective area of the first secondary air passage. The second secondary air passage includes a second vacuum operated air control valve and an electrically operated air control valve positioned in series. Intake manifold vacuum operates the second vacuum operated air control valve to vary the effective area of the second secondary air passage. An air-fuel ratio control which includes an intake air temperature sensor, an exhaust gas oxygen concentration sensor and a throttle plate vacuum sensor determines the engine air-fuel ratio to intermittently open and close the electrically operated air control valve to open and close the second secondary air control passage. The air-fuel ratio control also operates the electrically operated vacuum control valve to gradually open and close the first vacuum operated …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.