Cams 👍 Flashcards
What does a cam do
A CAM changes the input motion, which is usually rotary motion to a reciprocating motion of the follower. They are found in many machines and toys
How many parts does a cam have
2
What are the 2 parts of a cam called
Follower
Cam profile
How does the cam work
You push the follower up and the cam profile slowly rotates anti-clockwise while the follower slowly drops back down. It rotates anti-clockwise until it has turned 360 degrees
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
What are the different types of profiles
Pear .
Eccentric.
Heart .
Drop (snail)
What are the different types of follower
Flat
Point knife
Roller
Off set
Fall
The part of the cam that uses the follower to fall
Describe how 6 frames of a pear shaped cam would look/how it happens (short)
In frame 1 the cam is in a vertical position and it slow rotates in an anticlockwise direction. As it rotates the follow drops down. In frame 4 the follower is in its lowest position. The cam continues to rotate and the follower begins to rise in frames 5 and 6 until it returns to its original position.
How can you decide how fast the profile rotates?
If you turn it gently it will rotate slowly. The faster you turn it the faster it will rotate.
What is the profile
The shape of the cam is called the profile. They can be in any shape depending on the way the follower is going to move.
Tell me about a pear cam profile
They are used on the shafts of cars. The follower remains motionless for about half of the cycle of the cam and during the second half it rises and falls.
Tell me about an eccentric cam profile
Circular cams or eccentric cams produce a smooth motion. These cams are used in steam engines.
