Patent ID: 6415647
Filing Date: 2002-07-09
Classification: G01N,Y10T

Abstract:
A gas sensor comprising:a gas sensing element having an gas-exposed portion; a hollow housing having a first and a second end, said housing holding said gas sensing element therein so as to arrange the gas-exposed portion outside said housing for exposure to a gas to be measured; a protective cover installed on the first end of said housing to cover the gas-exposed portion of said gas sensing element; leads connecting with said gas sensing element, extending from the second end of said housing for electrical communication with an external device; a metallic cover installed on the second end of said housing, said metallic cover including a small-diameter portion, a large-diameter portion greater in diameter than the small-diameter portion, and a shoulder portion connecting the smaller-diameter portion and the large-diameter portion; and an insulator including a body and a flange projecting from the body, having disposed therein said leads connecting with said gas sensing element, the body having an outer diameter smaller than an inner diameter of the small-diameter portion of said metallic cover and being disposed within the small-diameter portion, the flange having a first and a second end surface opposed to each other and an outer diameter which is smaller than an inner diameter of the large-diameter portion of said metallic cover and which is greater than the inner diameter of the small-diameter portion, said insulator being disposed in said metallic cover with the first end surface of the flange urged by an elastic member to bring the second end surface into constant engagement with an inner wall of the shoulder portion of said metallic cover.