Abstract: The present invention aims to provide a gas sensor that can favorably be assembled by proper positioning of a connection terminal relative to a separator and a subassembly unit for such a gas sensor. In an oxygen sensor, a separator has protruding portions formed on a surface of a front end part thereof; an outer connection terminal has an outer fitting portion fixed to outer circumferential surfaces of the protruding portions under its biasing force; and an inner connection terminal has an inner fitting portion fixed to inner circumferential surfaces of the protruding portions under its biasing force. Thus, it is less likely that the outer and inner connection terminals will be displaced in position relative to the separator and is possible to allow proper positioning of the outer and inner connection terminals.

Abstract: The present invention aims to provide a gas sensor that can favorably be assembled by proper positioning of a connection terminal relative to a separator and a subassembly unit for such a gas sensor. In an oxygen sensor, a separator has protruding portions formed on a surface of a front end part thereof; an outer connection terminal has an outer fitting portion fixed to outer circumferential surfaces of the protruding portions under its biasing force; and an inner connection terminal has an inner fitting portion fixed to inner circumferential surfaces of the protruding portions under its biasing force. Thus, it is less likely that the outer and inner connection terminals will be displaced in position relative to the separator and is possible to allow proper positioning of the outer and inner connection terminals.

Abstract: The present invention relates to improvement in the corrosion resistance of a weld joint between a metal shell and an outer casing. As a solution to this object, a metal shell 11 and an outer metal casing 16 are laser welded to each other via a weld joint 100 by irradiating a laser beam onto the entire circumference of a crimped area 90 in a circumferential direction of the outer metal casing 16. This laser welding operation is performed at a plurality of positions (two positions) displaced from each other in the direction of an axis O so that the weld joint 100 is formed with a front weld zone 110 and a rear weld zone 120.