| 摘要 |
PURPOSE:To detect an air fuel ratio with high accuracy over a wide range by supplying a current to an oxygen partial pressure control part so that the output of the oxygen partial pressure detection part of an oxygen sensor attains to a command, and detecting the voltage between electrodes of this oxygen partial pressure control part. CONSTITUTION:Exhaust gas is admitted into a gas introduction part 18 and the oxygen partial pressure detection part SC has electrodes 20 and 21 which faces each other across an oxygen ion conductive solid electrolyte 14 and is exposed to the gas at the gas introduction part 18 and gas with specific oxygen thickness. The oxygen partial pressure control part PC has electrodes 22 and 23 which faces across an oxygen ion conductive solid electrolyte 17 and the current is so supplied to the control part PC that the output of the detection part SC attains to the command. Then, the voltage between both electrodes 22 and 23 of the control part PC is led out as a detection output which indicates the air fuel ratio. |
