Patent · US Expired

Heater control apparatus for oxygen sensor

US5719778A · kind A · utility

36Cited by
12References
38Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 10, 1995
Grant dateFeb 17, 1998
Priority date
Expiry dateJul 10, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05D23/1928
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In a heater control of an oxygen sensor, a heater control circuit is rendered fully conductive at 100% duty initially to supply full power to a heater until the resistance value of the heater reaches a predetermined initial value corresponding to a predetermined temperature. Then, the duty of the heater control circuit is feedback controlled so that the heater temperature becomes a target value until the internal resistance of the oxygen sensor reaches a target temperature, and further, after the internal resistance of the oxygen sensor S reaches the target temperature, the duty of the heater control circuit is feedback controlled so that the element temperature of the sensor becomes a target value.

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