Patent ID: 6913678

Claim:
A gas sensor comprising: a gas sensing element extending in a longitudinal direction of said gas sensor; a cylindrical insulator having a through hole into which said gas sensing element is airtightly inserted; and a cylindrical housing airtightly supporting said cylindrical insulator via an annular metallic packing, wherein an annular receiving surface provided on an inside wall of said housing supports said insulator via said metallic packing, said annular receiving surface extending in a radial direction with a predetermined inclined angle with respect to an axis of said gas sensing element, said insulator has a small-diameter portion and a large-diameter portion which are continuously aligned in an axial direction of said insulator, an outer cylindrical surface of said insulator includes a small-diameter cylindrical surface extending in parallel with the axis of said gas sensing element, a tapered surface, and a large-diameter cylindrical surface extending in parallel with the axis of said gas sensing element, said tapered surface extends in a radially outer direction with a predetermined inclined angle with respect to the axis of said gas sensing element from said small-diameter cylindrical surface to said large-diameter cylindrical surface, an outer circumferential portion of said tapered surface being in line contact with one surface of said metallic packing, and said annular receiving surface of said housing is in face-to-face contact with the other surface of said metallic packing.