Cam and Follower | Definition and Types Explained with Images

Definition of Cam

A cam is a mechanical member used to impart desired motion to follower by direct contact

Cam and follower combination belongs to the category of higher pairs.

Also read

• What are higher pairs?

Necessary members of cam and follower mechanism are

1. A driver member known as cam
2. A driven member known as follower
3. A frame which supports the cam and guides the follower

Types of Cams

Cams can be classified according to

1. Shape
2. Follower movement
3. Manner of constraint of the follower

Classifications of Cams according to shape

• Wedge and flat cams

• Radial or disc cams

• Spiral cams

• Cylindrical cams

• Conjugate cams

• Globoidal cams

Image source

• Spherical cams

Classifications of Cams according to follower movement

• Rise return rise

• Dwell rise return dwell

• Dwell rise dwell return dwell

Classifications of Cams according to constraint of the follower

• Preloaded spring cams

• Positive drive cams

• Gravity cam

Types of followers

Cam followers can be classified according to

1. Shape
2. Movement and
3. Location of line of movement

Classifications of followers according to shape

Image source

• Knife edge follower

• Roller follower

• Mushroom (or Spherical) follower

• Plate type follower

Classifications of followers according to movement

• Reciprocating follower

In this type, as the cam rotates, the follower reciprocates or translates in the guides.

• Oscillating follower

The follower is pivoted at a suitable point on the frame and oscillates as the cam makes rotary motion.

Classifications of followers according to line of movement

• Radial follower

The follower is known as a radial follower if the line of movement of the follower passes through the centre of rotation of cam.

• Offset follower

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If the line of movement of follower is offset from the centre of rotation of the cam, the follower is known as an offset follower.

Image sources

Flat, radial, cylindrical cam