From DT Online
A Snail Cam (aka Drop Cam), so-called because of the snail-like appearance, has a slow rise and then a sudden drop. This is a one-event-per-turn cam with a slow build-up to the peak and a rapidly decreasing edge. These cams can rotate in one direction only, which in the case of the illustration shown, is counter-clockwise.
Features and Applications
Snail Cams are a particular type of Radial Cam and can be used to drive punches, hammers, automata, or drum sticks in mechanical fairground organs - or any circumstance when a sudden drop is required.
|Disc Cam - the cam profile is an Archimedian spiral so the follower’s speed is constant. Gravity maintains permanent contact between follower and cam.||Disc Cam - the pink Input cam is driven by a motor and the orange weight maintains contact between the cam and red pin of the yellow follower. The blue cable should be wound more than one revolution on green pulleys to increase friction torques.|
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