Roller blind for covering window has winding roller containing spring exerting tension against crossbar with its ends attached to cords passing over rollers and attached to pistons in cylinders

摘要

The roller blind (10) is wound up on a roller (12) containing a tensioning spring (14). The end of the blind (16) pulls against a crossbar (18) with a centrally-positioned handle (20) and a slot (26) to accommodate a fixed locking catch (28). The ends of the crossbar are attached to sliders (22). These are attached to cords passing over guide rollers (36) and attached to pistons (32) in cylinders (30) which may act as dampers with flap valves controlling admission of air on either side of pistons.