Control method of oxygen concentration sensor

Abstract

Abstract PURPOSE:To bring a detecting part of an oxygen concentration sensor to an operational state quickly immediately after the start of an engine and to avoid a blackening phenomenon, by starting the supply of a heater current to a heater element when the specified starting state of the engine is detected. CONSTITUTION:A detecting part 1 of an oxygen concentration sensor, which is arranged in the exhaust system of an internal combustion engine, is composed of an oxygen-ion conductive solid-state electrolyte material 12 and pairs of electrodes 16a, 16b, 17a and 17b, which hold the material. The solid-state electrolyte material 12 and the pair of the electrodes 16a and 16b act as an oxygen pump element 18. The solid-state electrolyte material 12 and the pair of the electrodes 17a and 17b acts as a battery element 19. A heater element 20 is provided so as to heat the elements 18 and 19 on the outer wall surface of an atmosphere reference chamber 15. When the fuel in the engine 2 is completely detonated, supply of a heater current to the element 20 is started based on the control of a control part 4. The detecting part 1 comprising the element 18 and 19 is quickly heated by the heating of the element 20. thereafter, the increase in internal resistance to the value with in a specified range owing to the temperature increase of the element 20 is detected. At this time, supply of a pump current to the element 18 is started. Thus the flow of the excessive pump current is prevented.

Inventors

• 👤 Toyohei Nakajima
• 👤 Toshiyuki Mieno

Bibliographic Details