Detection of air-fuel ratio rich-lean imbalance using an oxygen sensor
US9453782B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 3, 2014 |
| Grant date | Sep 27, 2016 |
| Priority date | — |
| Expiry date | Jun 12, 2035 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A system and method for detecting air-fuel ratio rich-lean imbalance in an automotive engine cylinder is provided. The system and the method are configured to receive an oxygen sensor voltage of an oxygen sensor. They also include filtering the oxygen sensor voltage to create a filtered oxygen sensor voltage. An engine speed and load are determined, and an air-fuel ratio imbalance detection threshold is determined based on the engine speed and the engine load. A rich-lean imbalance status is determined, the rich-lean imbalance status being non-normal if any portion of the filtered oxygen sensor voltage exceeds the air-fuel ratio imbalance detection threshold, and the rich-lean imbalance status being normal if none of the filtered oxygen sensor voltage exceeds the air-fuel ratio imbalance detection threshold. An engine control unit having several control logics to execute similar steps is also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.