Patent ID: 6500322
Filing Date: 2002-12-31
Classification: G01N

Abstract:
A gas sensor comprising:a detecting element having electrodes on first and second surfaces of an oxygen ion conductive solid-state electrolyte; a main fitting having a fitting portion to be fitted into a mounting hole formed on a wall of a pipe defining a flow path for a gas-to-be-measured for holding said detecting element in such manner that said first surface is disposed via said mounting hole at an inner position of said pipe with respect to said fitting portion; a cylindrical cover of which one end is connected to an outer position of said pipe with respect to the fitting portion of said main fitting and the other end is provided with a cylindrical sealing member, said sealing member having an air hole extending therethrough in an axial direction for introducing air to said second surface and a through hole through which leads connected to the electrodes of said detecting element pass; and a gas permeable water repellant filter for closing said air hole, characterized in that said water repellant filter is formed in a sheet shape and mounted on said air hole by means of an inserting member inserted into said air hole and said water repellant filter is interposed between an outer peripheral surface of said inserting member and an inner peripheral surface of said air hole so as to close an open end of said inserting member.