Failure diagnostic apparatus and failure diagnostic method for gas concentration detecting apparatus
US6882927B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 15, 2003 |
| Grant date | Apr 19, 2005 |
| Priority date | — |
| Expiry date | Dec 15, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/4175
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A failure diagnostic apparatus for a gas concentration detecting apparatus is provided, which can early detect disconnection in a cell included in the gas concentration detecting apparatus. The gas concentration detecting apparatus is provided, which includes cells each of which pumps out oxygen in a gas detection chamber, thereby generating an electric current corresponding to the concentration of oxygen in the gas detection chamber. A heater which heats each of the cells to an activation temperature is provided. A period during which a predetermined electric current should flow in the cell after the heater starts heating is detected. A determination on whether there is disconnection is made based on whether each of electric currents flowing in the cells is appropriate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.