Pulleys 5 and 6 rotate about fixed axes A and B. Flexible link 4 runs over pulleys 5 and 6, guide rollers 7, rotating about fixed axes D, and idler pulley 1 which rotates about axis C of slider 2. Slider 2 moves in fixed guides a-a. The required tension of link 4 is maintained by weight 3.
$3501$SFL,ML$