Patent · US Expired

Method and apparatus for determining combustion mixture air/fuel ratio

US4125374A · kind A · utility

6Cited by
6References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 21, 1977
Grant dateNov 14, 1978
Priority date
Expiry dateNov 21, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T436/22
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A wide range combustion mixture air/fuel ratio sensor in which an electrochemical cell supplies hydrogen gas to a palladium sensor element at a rate regulated by the output of a Wheatstone bridge circuit incorporating the sensor element. This generated hydrogen gas combines with any oxygen present in the exhaust gas through catalytic action and also maintains the level of absorbed hydrogen, and therefore the electrical resistance of the palladium sensor element, at a preselected value. The magnitude of the current applied to the electrochemical cell necessary to maintain this balance is a measure of the combustion mixture air/fuel ratio.

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