Soft linear O2 sensor
US6481427B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 16, 2000 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Dec 13, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D2041/1432
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
The switching characteristic of zirconia solid electrolyte type oxygen sensors is shaped to generate a limited proportional range around the stoichiometric A/F through a modified operation of the port injection or direct fuel injection control system. The linear response is obtained by imposing fuel-injection offsets, of particular patterns and magnitudes, on the average fuel quantity determined by the closed-loop fuel controller. The linear range of the sensor is then used for precise stoichiometric A/F control for tailpipe emission improvements. Also, further reductions in HC and CO emissions during cold-start (with leaner air-fuel ratio operation) and reduction in NOx (slightly rich air-fuel ratio operation) under warm-up and hot conditions are made possible using production O2 sensors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.