Device for producing control signal for feedback control of air/fuel ratio
US4306957A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 1980 |
| Grant date | Dec 22, 1981 |
| Priority date | — |
| Expiry date | Jul 25, 2000 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02B1/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A device comprising an oxygen-sensitive element to be disposed in a combustion gas exhausted from a combustor to detect deviation of actual air/fuel ratio from a stoichiometric ratio. The element is a combination of two oxygen concentration cells each having a solid electrolyte layer, a measurement electrode layer formed on one side of the electrolyte layer, a reference electrode layer formed on the opposite side and covered with a shield layer. Either measurement electrode layers or reference electrode layers of the two cells are connected to each other, and a constant DC voltage is applied to the element to force a current to flow through solid electrolyte layers of both cells to cause migration of oxygen ions therethrough, from the measurement electrode to the reference electrode in one cell and reversely in the other. The device has a circuit to make a comparison between a fixed reference voltage and an output voltage developed between the measurement and reference electrodes of one cell of the element to produce a high-or-low level control signal according to the result of the comparison. The output voltage is independent of the internal resistance of the element and is scarce…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.