Abstract: A pair of separators is overlapped and placed on a base jig and thereby positioned with each other. Respective through-holes thereof are positioned to the position of a pin hole provided in the base jig. When a main jig is pressed against the base jig to clamp the pair of separators, and a pin of a sub-jig is inserted into the pin hole to clamp the pair of separators by a head, an annular light guiding path is formed by a gap generated between an opening provided in the main jig and the head of the sub-jig, and hence a laser welding position which surrounds the through-holes is exposed. The surrounding of each through-hole is seamlessly laser-welded when the laser welding position is irradiated with a laser beam.

Abstract: A welding position is provided which can prevent surface pressure drop in a seal bead in a pair of metal gaskets is determined. Joint surfaces of a pair of metal gaskets are joined to each other by welding. The pair of metal gaskets include a seal bead that encloses opening and a plurality of structures that bulge from the joint surfaces. A pressure-sensitive medium is sandwiched between the seal bead and a member to be engaged so that the pair of joined metal gaskets and the member to be engaged are stacked on one another, and the pair of joined metal gaskets are tightly engaged with the member to be engaged. The tight engagement is released, and a surface-pressure-drop location in the seal bead is detected based on a mark which remains on the pressure-sensitive medium after the release of the tight engagement.

Abstract: A device is used for forming a part by welding a plurality of members together, and includes a jig on one side having a joint face on one side, which is adapted to contact one of faces exposed on the outer surface sides of the plurality of members overlaid one on top of the other, and an opening on one side corresponding to a portion of desired welded portions of the part; a jig on another side having a joint face on the other side, which is adapted to contact another face of the faces exposed on the outer surface sides of the plurality of members, and an opening on the other side corresponding to another portion of the desired welded portions of the part and not corresponding to the opening on one side; a laser welding machine on one side that is configured to emit a laser beam toward the opening on one side; and a laser welding machine on the other side that is configured to emit a laser beam toward the opening on the other side.

Abstract: A welding jig device is used for forming a part by welding a plurality of members together, and includes a jig on one side having a joint face on one side, which is adapted to contact one of faces exposed on the outer surface sides of the plurality of members overlaid one on top of the other, and an opening on one side corresponding to a portion of desired welded portions of a part; and a jig on another side having a joint face on the other side, which is adapted to contact another face of the faces exposed on the outer surface sides of the plurality of members W, and an opening on the other side corresponding to another portion of the desired welded portions of the part and not corresponding to the opening on the one side.

Abstract: A welding position is provided which can prevent surface pressure drop in a seal bead in a pair of metal gaskets is determined. Joint surfaces of a pair of metal gaskets are joined to each other by welding. The pair of metal gaskets include a seal bead that encloses opening and a plurality of structures that bulge from the joint surfaces. A pressure-sensitive medium is sandwiched between the seal bead and a member to be engaged so that the pair of joined metal gaskets and the member to be engaged are stacked on one another, and the pair of joined metal gaskets are tightly engaged with the member to be engaged. The tight engagement is released, and a surface-pressure-drop location in the seal bead is detected based on a mark which remains on the pressure-sensitive medium after the release of the tight engagement.

Abstract: A pair of separators is overlapped and placed on a base jig and thereby positioned with each other. Respective through-holes thereof are positioned to the position of a pin hole provided in the base jig. When a main jig is pressed against the base jig to clamp the pair of separators, and a pin of a sub-jig is inserted into the pin hole to clamp the pair of separators by a head, an annular light guiding path is formed by a gap generated between an opening provided in the main jig and the head of the sub-jig, and hence a laser welding position which surrounds the through-holes is exposed. The surrounding of each through-hole is seamlessly laser-welded when the laser welding position is irradiated with a laser beam.