| 摘要 |
PURPOSE:To prevent rainwater to entering a duct and to prevent back pressure from being generated in the duct by providing slit grooves in the lower part of a sleeve and a drain hole at the outer end of an outer tube. CONSTITUTION:The part 2 of 1/3 in the lower part of a sleeve and an outer tube 3 form a double tube. In the inner tube part 2 of the double tube, a plurality of slit-like groove holes 4 are formed in the circumferential direction so that overflowing rainwater is discharged from an outer drain hole 5 through the outer tube part 3. The outer surface side of a windbreak plate 6 is flat and an inner surface side is formed in an inverted conical shape. Accordingly, exhaust air from a duct 9 is exhausted in the direction of 360 deg. of the outer wall of a bulding along the invertied conical surface. Upon strong wind produced because of the presence of the building, the exhaust air flows between the sleeve 1 and the windbreak plate 6 in one direction along the outer wall surface of the building irrespective of wind direction and hardly becomes back pressure in an indoor side in association with a venturi effect. |
