Secondary air injection diagnostic system using pressure feedback
US6983590B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 2002 |
| Grant date | Jan 10, 2006 |
| Priority date | — |
| Expiry date | Oct 22, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A diagnostic system according to the present invention diagnoses system failure of a secondary air injection system. The secondary air injection system includes a pump that provides air to an exhaust system via a conduit and a valve that controls the flow of air through the conduit. A pressure sensor measures pressure in the conduit. A controller predicts pressure in the conduit during first, second and third operational phases of the secondary air injection system. The controller compares the measured pressure to the predicted pressure to evaluate operation of the secondary air injection system. During the first phase, the secondary air injection system is used to reduce vehicle emissions. During the second phase, the valve is shut while the pump is on. During the third phase, the pump is turned off while the valve is closed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.