Drum 1 rotates continuously about fixed axis D and has a common geometrical axis with driven disk 2. Slots in disk 2 contain balls 3 which are subject to the action of compression springs 4 and are prevented from jamming between drum 1 and disk 2 by pins a which are mounted in disk 6. Disk 6 rotates freely about shaft 8 and is restricted against rotation by lug b of starting lever 7 which turns about fixed axis A. When starting lever 7 is momentarily turned clockwise, compression springs 4 push balls 3 so that they jam between disk 2 and drum 1, engaging them so that disk 2 begins to rotate. At the end of one revolution, lug c of disk 6 engages lug b of l ever 7 which has returned to its initial position. At this, pins a disengage disk 2 from drum 1. Reverse rotation of disk 6 is prevented by cam 5 and pawl 9 which turns about fixed axis B. Pawl 9 and lever 7 are held in contact with cam 5 and disk 6 by springs 10 and 11.
$3447$CF,D$