| 摘要 |
PURPOSE:To secure electromotive force with only displacement of a slight amount of reference air by providing at least two airtight parts, and communicating at least one or more second spaces which are formed between said sealing parts to atmosphere. CONSTITUTION:The axial line passing through a lateral hole 34 is formed so as to cross the axial line passing through a communicating hole 36 at a right angle. A space 32a in the inside of an oxygen sensor 20 is communicated to atmosphere through a lateral hole 34, a space 32b and the communicating hole 36. Meanwhile, a minute water repellent gap 25 is provided at a ring 23 made of a water repelling material between a cap 26 and a fixing metal fitting 21. Water is repelled, and only air is made to pass. In this constitution, exhaust gas which passes through the gap formed by a spacer 28, a sensor element 22 and the cap 26 and intrudes into spaces 32a and 32b by way of an airtight sealing part 30b on the exhausting side is discharged to the outside through the lateral hole 34, the space 32b and the communicating hole 36. Therefore, the gas does not reach the space on the reference air side, and the decrease in electromotive force of the sensor element can be prevented. |
