Air intake side secondary air supply system for an internal combustion engine with a duty ratio control operation
US4705012A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 11, 1985 |
| Grant date | Nov 10, 1987 |
| Priority date | — |
| Expiry date | Dec 11, 2005 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D41/1456
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An air intake side secondary air supply system for an internal combustion engine has an air intake system using a carburetor and an air intake side secondary air supply passage leading downstream of the carburetor. The passage includes an oxygen concentration sensor producing an output signal whose level is substantially proportional to an oxygen concentration of the exhaust gas. A control means for controlling a flow control valve is disposed in the air intake side secondary air supply passage and operates in accordance to the output signal of the oxygen concentration sensor. In a variation of the invention, the feedback control of air-fuel ratio using the output signal of the oxygen concentration sensor is effected only when the engine operational state is in a predetermined operational region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.