Cam and Follower Mechanism

Introduction:

A cam is a reciprocating, oscillating or rotating body that imparts reciprocating or oscillating motion to the follower, with which it is in contact. The shape of cam depends upon its motion and time of dwell, it also depends on the nature of surface in contact with the follower. There are different classification and types of cam, which are described further. It has seen that the follower usually has a line contact with the cam, so that the follower and cam constitute a higher pair. With few exceptions of the motion of the follower is only determined positively by cam during a part of each stroke, while during rest of stroke contact between cam and follower has to be maintained by an external force. This external force has to be provided by a compression spring although sometimes weight of the follower is sufficient.

Complicated motions, which are difficult to achieve, are easily achieved with the help of cam. Cams are widely used in automatic machines, IC engines, machine tools, printing control mechanism, dye casting, milling and punch presses. Cam is the main cause behind the opening and closing of inlet and exhaust valve timely.

A driver member is known as Cam.

A driven member is known as Follower.

A Frame is that which supports the cam and guides the follower.