| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent corrosion of a core member and realize sound absorbency at a heat insulation layer of a flexible duct.SOLUTION: A flexible duct 1 comprises: a helical-formed metallic core member 11; an inner membrane member 12 of which shape is formed into a tubular shape by the core member 11; and a heat insulation layer 13 having sound absorbency as well as adiabaticity to enclose an outer circumference of the inner membrane member 12. The core member 11 of the flexible duct 1 has engaging parts 11a, 11a for fixing the inner membrane member 12 from sides opposite to the side of a gas flow passage 19 and the core member is covered by the inner membrane member 12 from the side of the gas flow passage 19. The inner membrane member 12 is constituted by non-woven fabric.</p> |
