Method for controlling oxygen concentration sensor

Abstract

Abstract PURPOSE:To prevent the erroneous discrimination of an air/fuel ratio immediately after the heater current supply is started by starting the pump current supply to electrodes made of oxygen pump elements after the prescribed period has elapsed since the heater current supply to a heating element was started. CONSTITUTION:A pump current is supplied so that the outer peripheral layer 11 of the oxygen pump element 4 becomes a positive electrode, whereby oxygen lying in a clearance part 8 is pumped out of the oxygen pump element 14 to develop an oxygen concentration difference between an exhaust gas and the gas in the clearance part 8. Due to this oxygen concentration difference, a voltage is generated between a battery element 5 and electrode layers 13 and 14. A pump current value IP is controlled to a preset value, whereby the generated voltage between the battery element 5 and the electrode layers 13 and 14 can be approximately proportionate to the oxygen density in the exhaust gas. When a heater current supply circuit 36 supplies the heater current, the heating elements 6 and 7 heat themselves, and heat an oxygen density detecting element 3.

Inventors

• 👤 Tomohiko Kawanabe
• 👤 川鍋　智彦
• 👤 Masahiko Asakura
• 👤 正彦 朝倉
• 👤 Noritaka Kushida
• 👤 櫛田　孝隆
• 👤 Takanori Shiina
• 👤 椎名　孝則

Bibliographic Details