Cams Flashcards
One cycle
One rotation/revolution of the cam.
Dwell
When the cam rotates but the follower does not rise or fall.
The rise
That part of the cam that causes the follower to rise.
Pear shaped cams
Used on shafts of cars
Follower remains motionless for about half of the cycle of the cam
Second half it rises and falls
Eccentric
Produce a smooth motion
Used in steam engines
Heart shaped cams
Allows the follower to rise and fall with uniform velocity
Snail cam
Used on production lines
It causes the follower to remain stationary for half a turn before gently rising and suddenly falling. They can only work by rotating in one direction.
Shape of the cam is called?
The profile
The follower
The part that rests on the cam and moves up and down is called the follower
3 main types of followers
Flat, knife and roller
Flat follower
This type of follower has a large flat surface at its base. It is used when it is not
necessary that it follows a very precise cam profile
The cam will move in rotary motion (round and round!) while
the follower will move in reciprocating motion (up and down!).
Knife followers
These are mainly used with heart shaped cams as they can follow a very detailed
profile
Roller followers
This type of follower has a small roller bearing at the end. They are useful for
reducing friction and wear between the cam and the follower.
