Differential pressure-based enablement of a particulate filter diagnostic
US8966882B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2012 |
| Grant date | Mar 3, 2015 |
| Priority date | — |
| Expiry date | Jan 3, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A vehicle includes an engine, an exhaust system having a particulate filter which removes soot from the exhaust stream, a sensor, and a controller. The sensor measures instantaneous differential pressure across the filter. The controller executes a method to selectively enable or disable execution of an efficiency diagnostic of the filter as a function of a learned differential pressure offset value. The controller may also compare the differential pressure to a calibrated threshold and execute a control action when the differential pressure falls within an allowable range of the threshold. This may include applying the differential pressure offset value and enabling execution of the diagnostic using measurements from the zeroed sensor. Another control action may be executed when the measured differential pressure is not within the allowable range of the threshold, including disabling the execution of the diagnostic and setting a diagnostic code indicating that the sensor may be faulty.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.