Patent · US Expired

Gas sensing apparatus

US4897174A · kind A · utility

16Cited by
31References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 24, 1988
Grant dateJan 30, 1990
Priority date
Expiry dateMay 24, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N27/4077
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Apparatus for measuring the concentration of oxygen in exhaust gases. A gas sensor element of yttria-stabilized zirconia (Y.sub.2 O.sub.3 -ZrO.sub.2) has at one end a gas pump of two chambers separated by intervening Y.sub.2 O.sub.3 -ZrO.sub.2 with an orifice extending between each chamber and the exterior of the gas sensor element. Two platinum electrodes of a first set face one chamber and two platinum electrodes of a second set face the other chamber. The gas sensor element is mounted in an insulating mounting collar in close contact with two ceramic heaters of resistance heating elements on silicon nitride substrates. The mounting collar is clamped between a shield member encircling the gas pump of the sensor element and a housing member by threaded clamping nuts. The shield member has one or more apertures therein to admit exhaust gases to be analyzed to the gas pump of the sensor element. The housing member has an electrical connector at one end which is spaced from the sensor element for providing electrical connections to the sensor element and the ceramic heaters.

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