| 摘要 |
PURPOSE:To provide an automatic shutter closing device in which not only the number of component elements can be decreased, but also their reuse can be performed and the device is operated when a fire occurs by a method wherein a stopper made of shape memory alloy is used in place of a temperature fuse stopper and an operating spring. CONSTITUTION:A stopper 14 made of shape memory alloy is returned to its original position when its temperature is reached to a melting point of a temperature fuse stopper in the conventional system and then the stopper is set to extend. With the stopper being set in this way, when a fire occurs and a surrounding temperature of the ventilation fan is reached to a shape returning temperature of the stopper 14 of shape memory alloy during a condition in which the switch is turned on, i.e. the shutter 6 is kept open, the stopper 14 of shape memory alloy is extended to cause the operating element 11 to be pushed down and a connection between the connector rod 7 and the wire 9 for the switch is released. Then, the connector rod 7 is raised up by the force of the shutter spring 15, resulting in that the shutter 6 is automatically closed. |
