| 摘要 |
PURPOSE:To control the gas mixing ratio of an internal combustion engine with high precision while reducing the damage of an electrode which comes into contact with a gas flow securely, by providing many gas intakes in the axial direction of the protection pipe of a concentration sense pipe. CONSTITUTION:The protection pipe 6 of a concentration sense pipe 3 is stuck atop of a plug body 2, and gas intakes 6a and 6'a are made in the side circumferential surface of the pipe 6; the deflection directions of deflecting pieces 6b and 6'b for the gas intakes are equalized to a constant circumferential direction, and the directions of the deflecting pieces are made opposite by turns in the axial direction. Then, exhaust gas entering through the holes 6a is deflected by the deflecting pieces 6b to round counterclockwise, and exhaust gas entering through the holes 6'a is deflected by the deflecting pieces 6'b to round clockwise. Therefore, flows of the gas inverted in deflection direction by turns as axial layers are generated in the sense pipe 3, and while a deflected flow in the circumferential direction is held, a contact flow free of deviation on the whole is generated. |
