Air-fuel ratio control system for internal combustion engines
US5724952A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1996 |
| Grant date | Mar 10, 1998 |
| Priority date | — |
| Expiry date | Jun 7, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D2041/1409
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
There is provided an air-fuel ratio control system for an internal combustion engine. The air-fuel ratio control system has an air-fuel ratio sensor arranged in an exhaust passage of the engine, which generates an output proportional to concentration of oxygen in exhaust gases emitted from the engine. The air-fuel ratio of a mixture supplied to the engine is controlled to a desired air-fuel ratio in response to the output from the air-fuel ratio sensor by the use of a proportional term and an integral term. A repetition period of inversion of the output from the air-fuel ratio sensor with respect to a predetermined reference value is calculated. Deterioration of the air-fuel ratio sensor is detected based the repetition period of inversion of the output from the air-fuel ratio sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.