Shutter for closing opening e.g. window, of roof of building, has frame fixed on building, and flexible link co-operating with return unit and rolled up on idle pulley in direction opposite to rolling direction of apron on shaft

摘要

The shutter has a frame fixed on a building. A pulley is rotatably integrated with a shaft. A return unit i.e. idle pulley (22), is arranged in the frame at a side opposite to a caisson. An end of a flexible link (8) e.g. elastic tensioner or cable, is integrated with the pulley, and another end (8b) of the flexible link is integrated with an apron. The flexible link co-operating with the return unit is rolled up on the pulley in direction opposite to rolling direction of the apron on the shaft.