Patent · US Expired

Air/fuel ratio detector

US4578171A · kind A · utility

17Cited by
4References
8Claims
0Family size

Assignees

Inventors

Key dates

Filing dateDec 13, 1984
Grant dateMar 25, 1986
Priority date
Expiry dateDec 13, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N27/4065
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An A/F ratio detector capable of accurately and unambiguously detecting the operating A/F ratio of a burner such as an internal combustion engine whether the engine is operating in the fuel-rich region, fuel-lean region or at the theoretical A/F ratio. The detector includes a solid-electrolyte oxygen pump element having a porous electrode formed on both sides of an oxygen-ion-conductive solid electrolyte, and a solid-electrolyte oxygen-concentration-difference-actuated electrochemical cell sensor element disposed to face the pump element with a small gap therebetween and which has two porous electrodes formed on opposite sides of an oxygen-ion-conductive solid electrolyte. An air compartment open to the atmosphere is formed on a side of the electrochemical cell sensor element opposite the small gap. The electromotive force generated by one pair of the porous electrodes on the electrochemical cell sensor element, the pump current flowing through the other pair of porous electrodes on the sensor element, or the pump current flowing through the porous electrodes on the pump element provides an output signal for A/F ratio detection.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.