System for feedback control of air/fuel ratio in IC engine with means to control supply of current to oxygen sensor
US4359030A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 1980 |
| Grant date | Nov 16, 1982 |
| Priority date | — |
| Expiry date | Oct 22, 2000 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D41/1494
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A system for feedback control of air/fuel ratio in an IC engine, utilizing an oxygen-sensitive device which is provided with a heater and disposed in exhaust gas to provide a feedback signal. This device has a porous solid electrolyte layer with an outer electrode layer on one side and an inner electrode on the other side facing a substrate. There is a circuit to supply a heating current to the heater and also force a DC current to flow in the solid electrolyte layer to cause migration of oxygen ions therethrough toward the inner electrode to thereby establish a reference oxygen partial pressure on the inner side of the solid electrolyte layer. This circuit is provided with current intensity regulation means to temporarily decrease the intensity of the current flowing in the solid electrolyte layer by a predetermined value while the oxygen-sensitive device is not sufficiently heated to thereby preclude undesirable rise of the basic level of the output voltage of the oxygen-sensitive device by the effect of an increased internal resistance of the not sufficiently heated element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.