The cam and follower is a mechanical device used to achieve the desired reciprocating
motion. The cam is the rotating member, and the follower is the reciprocating member. The
cam is a profiled disc, cylinder or sphere that rotates. The shape or profile of the cam
influences the motion of the follower. The follower is a rod that is in contact with the cam.
The contact between the cam and follower is achieved using spring or the follower's wAs the
cam rotates, its varying cross-section makes the follower in contact with it to reciprocate. The
frame or guide guides the follower while reciprocating and acts as a support for the cam and
Types of Cam Based on the Shape
.Radial Cam: A flat plate or disc is carved and is used as a cam to obtain the required motion
of the follower. In this type, the motion of the follower is perpendicular to the axis of rotation
of the cam.
.Cylindrical Cam: This cam is cylindrical in shape, and there is a groove cut on its surface.
The follower moves along the path of the groove. In this type, the motion of the follower is
parallel to the axis of rotation of the cam.
.Wedge Cam: The cam is in the shape of a wedge and has a sliding motion. The follower
moves up and down as the cam moves to and fro. Here the motion of the cam and follower
are perpendicular to each other.
.Conjugate Cam: Two rollers are connected to the follower in this cam. Both rollers restrict
the motion of each other, and this type of cam is used primarily for noiseless operation.
.Globoidal Cam: Globiodal cam is similar to cylindrical cam as they both have a groove cut.
The difference is that the surface of the globoidal cam is either concave or convex.
.Spherical Cam: The spherical cam also has a groove cut in it, and here, the cam is in the
shape of a sphere.
Compiled by Mr Murisa B (Harare Polytechnic Automotive Engineering Division)