Face cam 1 rotates about fixed axis A and has profiled groove a. Follower 2 turns about fixed axis B and carries roller 9 which rolls and slides along groove a. Follower 2 has screw 8 with a nut by means of which slider 7 can be adjusted to various positions along screw 8. This varies distance B͞C on follower 2. Connecting rod 3 is connected by turning pairs C and D to slider 7 and to lever 5 which turns about fixed axis E. Pawl 4 turns about axis D and periodically engages ratchet wheel 6 which rotates about axis E. When cam 1 rotates continuously, ratchet wheel 6 rotates intermittently with dwells, and the angle of rotation can be varied by means of screw 8.
$3351$CR,LL$