| 摘要 |
PURPOSE:To prevent the wind noise from being generated to substantially reduce the noise level by locating a semicircular part set in the bend of a shutter between the ends of two pins so as to form a continuous circle at the ends of the rotating shaft for the shutter. CONSTITUTION:One end of a shutter 7 is folded to form a bend 1w which has a semicircular section 13 in its middle part whose section configuration is semicircular and flat sections 16 on both sides formed by bending in the shape of a channel. Fitting holes 8 are formed at the locations where the semicircular section 13 and the flat sections 16 meet. The shutter 7 is rotatably supported by the bend 123 by fitting pins 9 from both sides into the holes 5 formed to oppose the side plates 1a, 1d of the outlet 1b of a casing unit 1. The pin 9 has at its end hooks 10, 14 which are engaged with the fitting holes 8 in the bend 12 and an axially extending fastening groove 11. The flat sections 16 of the bend 12 of the shutter 7 are fitted into the fastening groove 11. As the end of the hook 10 is engaged with the fitting hole 8 and the end of the hook 14 is inserted into the fitting hole 8, the bend 12 functions as the rotating shaft for the shutter 7. |
