| 摘要 |
PROBLEM TO BE SOLVED: To provide complete airtightness just by mutually fitting ducts and riveting them and completely eliminating a need for winding airtight tape. SOLUTION: When fitting an inner pipe 1 and an outer pipe 2 by providing an annular recessed groove 3 on at least one of opposing faces in mutual fitting parts of the inner pipe 1 and the outer pipe 2 in regard to the ducts, and fitting an annular band 5 in regard to a elastic packing 4 comprised by integrally and protrudedly providing an annular pressure receiving protruding piece 6 facing a diametral direction on the annular band 5 in the annular recessed groove 3, the pressure receiving protruding piece 6 is tilted in an axial direction of both pipe bodies by a tip of either one and it is pressed against the opposing face of the counterpart pipe body. |
