What is pressure angle and its significance in design of cam and follower mechanism?

Pressure angle and its significance:

It is defined as "angle made between the direction of motion of follower and normal to the pitch curve at any point".It varies from maximum to minimum during complete rotation. It should be small and the angle can be minimized by making bigger cam size or maintaining the offset.

If the pressure angle is high, higher the side thrust and chances of jamming the motion of follower in guideways.

If pressure angle is very small,Weight of cam will increase with increase in inertia force.