Limiting electric current type oxygen sensor with heater and limiting electric current type oxygen concentration detecting device using the same

摘要

The invention provides a limiting electric current type oxygen sensor with a microheater, having: an oxygen ionic conductor; an anode and a cathode respectively formed on two major surfaces of the oxygen ionic conductor; an insulating film which has a porosity of not less than 0.2 %!, an average pore diameter of not less than 140 Å!, and a thickness between 0.2 &mgr;m! and 10 &mgr;m!, and which is formed on one of the anode and the cathode so as to regulate a flow rate of oxygen gas and to provide electrical insulation; and the microheater formed on the insulating film. The oxygen ionic conductor is electrically insulated from the microheater through the insulating film. The invention also provides a limiting electric current type oxygen concentration detecting device having the limiting electric current type oxygen sensor and a constant temperature control circuit.