Patent · US Expired

Method of abnormality detection of oxygen concentration sensor

US4777922A · kind A · utility

20Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 27, 1987
Grant dateOct 18, 1988
Priority date
Expiry dateMar 27, 2007

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02D2041/2093
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Abnormalities are detected in an oxygen concentration sensor employed to sense the oxygen concentration in engine exhaust gas for obtaining data to control the air/fuel ratio of a fuel mixture supplied to the engine, in which the oxygen concentration sensor includes a sensor cell element and an oxygen pump element. The method functions to detect an abnormality of the oxygen concentration sensor on the basis of the value of sensor voltage which is developed by the sensor cell element and at least one of a set of parameters consisting of an engine operating condition, the value of pump current which flows between the electrodes of the oxygen pump element, and an air/fuel ratio compensation value which is derived from a sensed oxygen concentration level.

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