| 摘要 |
PROBLEM TO BE SOLVED: To provided a flexible pipe used in an air conditioning duct increased in heat insulation while flexibility is kept. SOLUTION: The conventional pipe obtaining by winding a coil spring 2b round the outer periphery of an aluminum foil tube 2a and forming a flocked layer 2c is taken as an outer pipe 2. A little smaller-diameter inner pipe 3 obtained by winding a coil spring 3b round the outer periphery of the aluminum foil tube 3a is inserted in the outer pipe 2, and the interior of the inner pipe 3 is made an air passage for air conditioning. External heat is intercepted by the outer pipe 2, besides the heat insulating effect is heightened by heat insulation of an air layer in a gap and thermal reflectivity of the outer peripheral surface of the inner pipe 3. |
