| 摘要 |
PROBLEM TO BE SOLVED: To increase the mechanical strength and heat resistance of a gas sensor installed in an internal combustion engine and the like for detecting a constituent to be detected in gas flowing through a gas flow pipe. SOLUTION: A main body metal fitting 4 provided in an oxygen sensor 2 is provided with an integrally formed leg part 10, an expanded diameter part 12, and a rear end part 14. In the rear end part 14, the cross section of a part ranging from a part equivalent to the upper end part of an insulative protection body 6 to the rear end is formed in a rectangle substantially. By means of guide parts 14a, 14b, 14c, 14d and 14e formed on the outside wall of the rear end part 14, and connecting direction is defined when an external connector member is fitted and connected around the outside wall of the rear end part 14. Consequently, the connection part 14 is asymmetric with respect to the central axis of the main body metal fitting 4. The main body metal fitting 4 is formed by using a metal injection molding method, in which the main body metal fitting with a predetermined shape is completed by sintering a molded product after a metal material is injected into a die so as to provide the molded product serving as an original form. |
