PURPOSE: To reduce the man-hours, suppress the manufacturing costs, and pre vent output of unacceptable products by furnishing detents consisting of No.1, No.2 flap in places at the perimeter of a base board to constitute a seal ring, and by pinching the inner edges of a through hole with the detents.
CONSTITUTION: Detents 15 consisting of No.1, No.2 flap 16, 17 each forms a couple are furnished in places at the perimeter of a base board 7 made of metal which constitutes a seal ring 6. This seal ring 6 is fixed fast to the inner side of a through hole 4 by pinching its inner edges with the No.1 flap 16 and No.2 flap 17 constituting each detent 15. Thus, man-hours are reduced, the manufacturing costs suppressed, and output of unacceptable products prevented.
TAKANAKA TOSHIMASA
MAEDA SHU
