Detection of malfunction in gas concentration detection system
US6164125A · kind A · utility
26Cited by
9References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 7, 1998 |
| Grant date | Dec 26, 2000 |
| Priority date | — |
| Expiry date | Apr 7, 2018 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D41/1456
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A gas concentration sensor voltage and current (in both heater on and heater off states) are detected and compared with predetermined thresholds, respectively, by a microcomputer. Based on a combination of the comparison results, the presence or absence of trouble in the system is detected and trouble location in the system is specified. In addition or alternatively, the sensor voltage is compared with thresholds to determine whether it is outside of a normal zone. The voltage may be actually detected or calculated. If the voltage is outside the normal zone, sensor voltage is reduced to zero or restricted to a predetermined limit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.