| 摘要 |
PROBLEM TO BE SOLVED: To provide a weather cover having a motor-operated fireproof damper serving also as a motor-operated shutter, which in case of a fire, etc., securely shuts off the passage for air. SOLUTION: When an air passageway 50 becomes heated to temperatures above a certain point, a thermal fuse 27 melts and a wire 26 is severed into two. Therefore, the force for winding up a wire exerted by a winding motor 23 is not transmitted to a damper 22a and by a spring 28a attached to the back of the damper 22a the damper 22a is turned on an axis 25a in the direction of closing the air passageway 50. With turn of the damper 22a toward closure of the air passageway 50, the force acting on a link 29 in the direction of the inside of the room dies down whereas the force exerted by springs 28b, 28c attached to dampers 22b, 22c gain and the dampers 22b, 22c also turn toward closure of the air passageway 50. Therefore, even while a pressure-creative blower is working, the spring 28a, etc., exerting the force on the damper 22a, etc., toward closure of the air passageway 50 overpowers the pressure of the current of air and closes the air passageway 50. |
