Patent · US Expired

Oxygen concentration detecting device

US4915813A · kind A · utility

15Cited by
5References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 9, 1988
Grant dateApr 10, 1990
Priority date
Expiry dateDec 9, 2008

Classification

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

Abstract

An oxygen concentration detecting device includes at least one oxygen concentration detecting element formed by an oxygen-pumping element and a cell element, composed of an oxygen ion-conductive wall, separating a pair of electrodes. The oxygen-pumping element and cell element define a gas diffusion chamber. A current detecting resistance forms a series circuit with the oxygen-pumping element. A voltage applying circuit applies to the series circuit an output voltage corresponding to the difference between a voltage between the electrodes of the cell element and a first reference voltage. An output detecting circuit outputs a voltage signal corresponding to a value of pumping current flowing through the resistance. An operational amplifier has a non-inverting input terminal supplied with a second reference voltage, an inverting input terminal connected to one end of the resistance, and an output terminal connected to the other end of the resistance. The output detecting circuit detects a first voltage at the one end of the resistance and a second voltage at the other end and outputs the voltage signal corresponding to the difference between the detected first and second voltages. T…

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