Diagnostic apparatus for an exhaust gas purification system of an internal combustion engine, an exhaust gas purification system and a diagnostic method thereof
US8341937B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 2007 |
| Grant date | Jan 1, 2013 |
| Priority date | — |
| Expiry date | Jan 1, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An apparatus for an exhaust gas system includes a main exhaust passage, a main catalytic converter disposed in the main exhaust passage, a bypass exhaust passage, a bypass catalytic converter disposed in the bypass exhaust passage, and a valve configured to open or close a section of the main exhaust passage. The bypass exhaust passage bypasses the main exhaust passage between a branch point of the bypass exhaust passage out of the main exhaust passage and a junction with the main exhaust passage at a upstream side of the main catalytic converter. A first sensor indicates a first air-fuel ratio of exhaust gas in the bypass exhaust passage. A second sensor indicates a second air-fuel ratio of exhaust gas flowing into the main catalytic converter. A controller determines whether the valve in the closed configuration leaks exhaust gas based on the first and second air-fuel ratios of exhaust gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.