Foldable image projection screen

摘要

In the unfolded state the projection screen (1) is vertically tensioned by a weighting beam (3) on the lower side of the screen. The beam connection is carried out indirectly by clamps (4), such a rubber clamp or spring. On both screen sides are fitted tensioning and support ropes (5) firmly coupled to the lower heavy beam. The ropes are linked to the screen side via eyelets, loops, or rings (6) which safeguard the screen tension in unfolded state. The ropes are secured are looped over deflection pulleys (7) on top support beam (2) and guided on winding drums (8), manually on or motor driven. In latter instance, the drum movement is controlled by limit switches.