The mechanism is intended for rapid return of the follower to the initial position. Disk 1 rotates counterclockwise about fixed axis A and is connected by spring 7 to cam 2 which turns freely about axis A. Follower 3 turns about fixed axis B and carries rollers 4 and 5. In the position shown, roller 4 enters recess b in cam 2 to lock follower 3. When disk 1 rotates, cam 2 and follower 3 remain stationary until pin a of disk 1 contacts roller 5, turning follower 3 and releasing cam 2. Follower 3 is swung farther to the right by the action of cam 2 on roller 4. If disk 1 is stopped in any position, follower 3 is rapidly returned to its initial position by spring 6.
$3347$CR,ML$