Patent ID: 7484401

Claim:
A gas sensor comprising: a sensor element for detecting the concentration of a particular gas contained in a measurement gas; a housing holding said sensor element; an air cover installed on an end of said housing; a lead wire making an electric contact with said sensor element; an elastic insulating member having a lead wire insertion hole for receiving said lead wire and sealing a base portion of said air cover, wherein said elastic insulating member has a longitudinal hole, formed in the axial direction thereof and open at an end thereof, and a passage portion communicating between said longitudinal hole and an outer side thereof; a tubular member forming an internal space that is open at an end thereof and having a through-hole penetrating between said internal space and an outer side of said tubular member, wherein the tubular member is disposed in said longitudinal hole; an air permeability filter wound around an outer circumference of said tubular member and crimped between said elastic insulating member and said tubular member, wherein said air cover is radially calked at plural axially spaced calking portions to retain said elastic insulating member; and an air vent, through which air is admitted into said passage portion of said elastic insulating member, the air vent being disposed between said multiple calking portions.