Belt 5 runs over two pulleys 1 and 8 which rotate about axis A of motor base 9, turning about fixed axis C, and about axis B of rocker arm 7, turning about fixed axis E. Belt 6 runs over pulley 11, rigidly attached to pulley 8, and over pulley 2 which rotates about fixed axis D. Belts 5 and 6 are tensioned by spring 4 which is enclosed in sleeve a of rod 3. Rod 3 is connected by turning pair K to arm 7 and by a sliding pair to plunger 10 which, in turn, is connected by turning pair L to motor base 9.
$3544$CFL,ML$