Abstract:
A method for manufacturing a gas sensor includes: disposing a tubular holder and a tubular compact in a tubular metallic shell defining a through hole, the tubular holder defining a first insertion hole, and the tubular compact defining a second insertion hole; preparing a preliminary assembly in which a pin is inserted into the first insertion hole and the second insertion hole; pulling out the pin from the first insertion hole and the second insertion hole and inserting a sensor element into the first insertion hole and the second insertion hole such that a forward end of the pin will come into contact with an end of the sensor element; compressing the compact to thereby fix the sensor element inside of the metallic shell; welding a protection sleeve to the metallic shell to thereby form a semi-assembly; and combining the semi-assembly with another semi-assembly to thereby form the gas sensor.
Abstract:
Disclosed is a sensor, including: a sensor body having a cylindrical case and a sensor element accommodated in the case; a seal member disposed in a rear end part of the case; lead wires electrically connected to the sensor element and extending from inside to outside of the casing through the seal member; and a cylindrical heat shield tube retained to an outer surface of the case and extending rearward from the case so as to circumferentially surround the seal member and parts of the lead wires, characterized in that: the sensor further includes a cylindrical tube cap made of an elastic material and arranged to restrict a rearward movement of the heat shield tube; the tube cap has formed therein at least one lead wire insertion hole through which the lead wires are inserted; and the tube cap is reduced in diameter and held to the lead wires.
Abstract:
A method for manufacturing a sensor intermediate product includes: disposing a tubular holder and a tubular compact in a tubular metallic shell, and inserting a metallic pin into a first insertion hole of the holder and a second insertion hole of the compact; compressing the compact so as to form a filling member intermediate having a shape which brings the filling member intermediate into pressure contact with the inner wall surface of the metallic shell and allows removal of the metallic pin from the second insertion hole; pulling out the metallic pin from the first insertion hole and the second insertion hole; inserting a sensor element into the first insertion hole and the second insertion hole; and compressing the filling member intermediate to thereby form a filling member which fixes the sensor element inside of the metallic shell.
Abstract:
Disclosed is a gas sensor including a metal shell, a ceramic holder placed in an axial inner hole of the metal shell and a sensor element inserted through an insertion hole of the ceramic holder. The ceramic holder has a recessed hole recessed toward the rear from a front-facing surface of the ceramic holder. The sensor element has, at a front end part thereof, a detection portion covered with a porous protection layer such that a rear end part of the protection layer is accommodated in the recessed hole with a space left therebetween. Further, the ceramic holder has a front circumferential edge defined between an inner circumferential surface of the recessed hole and the front-facing surface of the ceramic holder such that the whole of the front circumferential edge is located radially inside of a radially innermost position of the axial hole.