Patent · US Expired

Air fuel ratio detecting device

US5366610A · kind A · utility

3Cited by
7References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 28, 1989
Grant dateNov 22, 1994
Priority date
Expiry dateDec 28, 2009

Classification

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

Abstract

An air fuel ratio detecting device which is improved in accuracy as compared to similar prior art devices comprises a sensor cell for developing an electrical signal in response to the difference between the concentration of oxygen within an exhaust gas and the concentration of oxygen within a reference gas, a controlling means for developing an electrical control signal having a polarity determined from the output of the sensor cell, a pump cell for moving oxygen ions in response to the electrical control signal received from the controlling means, a control current detecting means for detecting control current flow between the controlling means and the pump cell, an air fuel ratio detecting means for detecting an air fuel ratio from the control current flow, a stoichiometric air fuel ratio detecting means for detecting the direction of the control current flow so as to determine the stoichiometric air fuel ratio, a storage means for storing therein a linear air fuel ratio value which is determined from a predetermined functional relationship with respect to the magnitude of the control current flow, a linear air fuel ratio detecting means for detecting the magnitude of the contro…

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