Shaft 1 rotates about fixed axis A. Rigidly mounted on shaft I is double-throw crankshaft a with c rank- pins c and b which are connected by turning pairs to frames 3 and 5. The body of screen 4 is attached to frame 3 and that of screen 2 to frame 5. Frame 3 is suspended on flexible links (ropes) 6, and frame 5 on flexible links (ropes) 7. When shaft 1 rotates, the bodies of screens 2 and 4 have circular motions.
$3530$SFL,FD$