Exhaust gas sensor temperature detection system
US4153023A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1977 |
| Grant date | May 8, 1979 |
| Priority date | — |
| Expiry date | Dec 23, 1997 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D41/1455
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
In a mixture control system having an exhaust gas sensor located in an exhaust system of an internal combustion engine for controlling the air-fuel ratio of the mixture supplied to the engine, a detection system for detecting when the temperature of the exhaust gas sensor is within its normal operating range. A deviation signal is derived from the exhaust gas sensor to represent the deviation of the air-fuel ratio within the exhaust system from a desired air-fuel ratio. The peak value of the deviation signal is detected and stored in a storage circuit and compared with a threshold which represents the normal operating temperature of the exhaust gas sensor to provide a disabling signal for the mixture control system to suspend feedback control operation when the temperature of the sensor falls below its normal operating temperature. The exhaust gas sensor is then supplied with a current in response to the presence of the disabling signal so that the voltage across the sensor's internal impedance increases because of its high impedance value at low sensor temperatures. The output from the gas sensor is compared with a preset value higher than the maximum output level of the sensor wh…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.