Cam and Follower Systems

A cam is a component on which a particular profile has been machined.   The profile of the cam imparts (causes) a follower to move in a particular way.  This can be seen if we examine the diagram below.  As the shaft is rotated the cam rotates with it causing the follower to move up and down.

Cams fall into two main categories:

1. edge, plate or face cams and

2. cylindrical cams.

Category No.1

The plate cam is merely a flat disc that has had a certain shape (or profile) machined on to it.  The follower is placed in contact with this profile and as the cam is rotated the profile of it translates into a particular movement of the follower usually up and down.  This can be seen in the diagram above.

The face cam is a disc the has a groove machined into its face and a roller follower is used to follow the groove as the cam rotates.

Category No.2

The cylinder or drum cam is a cylinder which has had a profile machined onto it and as the cam rotates the profile imparts a particular motion on its follower.

Types of follower:

There are three main types of follower:

1. the knife edge follower (seen in the cam and follower system table below)

2. the roller follower (seen in the cam and follower system table below)

3. the flat follower (seen in the cam and follower system table below)

The table below shows three different system each containing a different type of follower.

Knife edge follower	Roller follower	Flat follower