Swinging / Rocking Mechanisms
This type of mechanism produces a swinging or rocking motion of a link. The motion is generally less than 360o and is an oscillatory motion.
Toothed Rack System
This is simply a rotating arm (b) with a link fitted with a toothed rack (c) which meshes with a gear (d) to produce a rocking motion of the gear.
Crank and Rocker Mechanism
This is simply a four bar linkage (the frame provides the first link). The operating characteristics are dependent on the length of the links and the design of the frame setting the pivot points..Rotation of the arm (b) produces a rocking motion of arm (d).
Quick Return linkage
The arm (b) rotates and results in a rocking motion of arm (d)via the slider (c). The action is a quick return action because the angle (b) rotates through in one direction ,assumed to be the forward direction, is greater than the angle which result in the return motion.
Cam and Follower Mechanism
A very simplified version on this system is shown below. Rotation of the cam (c) produces a rocking motion of the lever (d) via the sliding interface (b). The arrangement below only identifies the principle involved. In practice some means would have to be provided to ensure the lever is maintained in contact with the lever.