Loading patent…
AssigneeNgk Spark Plug Co., Ltd.
InventorsTessho Yamada, Katsuhisa Yabuta, Takeshi Kawai, Hideki Toyoda
Estimating the term…
An oxygen sensor according to the present invention has battery element and a pump element in each of which porous electrodes are disposed on both faces of a solid electrolyte substrate. A minute current is supplied to the battery element after the start of energizing a heater and the activation of the sensor elements are judged on the basis of an interelectrode voltage generated at this energizing. A heater voltage is set to be 12V at the start of energizing. When the time period necessary for the interelectrode voltage to reach a predetermined voltage is short, the applied voltage is lowered to 11V. As a result, the time period necessary for judging the sensor elements to be activated can be made substantially constant irrespective of variations in sensor characteristics. After the activation judgment, the variation of the temperature of the sensor element is monitored on the basis of the interelectrode voltage. When the element temperature is varied, the heater voltage is raised or lowered so that the element temperature is stabilized.
A method of controlling the energizing of a heater for an oxygen sensor, said oxygen sensor including a first sensor element having a pair of porous electrodes disposed on both faces of a solid electrolyte, said solid electrolyte being oxygen-ion-conductive, and a heater being disposed in the vicinity of said first sensor element and being energized to heat said first sensor element, said method comprising the steps of:
An apparatus for controlling the energizing of a heater for an oxygen sensor, said apparatus being disposed in an oxygen sensor comprising a first sensor element having a pair of porous electrodes disposed on both faces of a solid electrolyte, said solid electrolyte being oxygen-ion-conductive;
Dependencies are inferred from the claim text.