Patent ID: 6341599
Filing Date: 2002-01-29
Classification: F02D,G01N

Abstract:
A heater control apparatus for controlling power supplied to a heater used to heat a solid electrolyte-made sensing element of a gas concentration sensor up to a temperature at which the sensing element is activated to provide a desired gas concentration output, said desired gas concentration output intermittently being read by automotive control circuitry, said heater control apparatus comprising:a power supply-controlling circuit controlling an electric power supply to the heater to bring a temperature of the sensing element of the gas concentration sensor into agreement with a target temperature value; and a target temperature value-determining circuit determining the target temperature value as a function of an environmental condition in which the gas concentration sensor is used and a use of the gas concentration sensor; wherein said target temperature value-determining circuit decreases the target temperature value during periods of time in which the gas concentration output from the gas concentration sensor is not required to be read by the automotive control circuitry and wherein said target value-determining circuit increases the target temperature value during periods of time in which the gas concentration output is required to be read by the automotive control circuitry.