cams

• cams are used in mechanisms to change rotary motion to reciprocating motion
• types of cams:

  • pear
  • eccentric
  • snail
• pear shaped = follower stays at the lowest position for half a turn and then rises and fall steadily

  
• eccentric = the follower rises and falls steadily

  A) follower

  
• snail = the follower will rise steadily and fall suddenly

  can only move in one direction or it will lock

  
• followers stay touching the edgy of cam by gravity or a return spring fitted to them
• cranks are like cams but have a slider that gets pushed and pulled

  A) crank

  B) slider

  
• carnks can be found in cars and bicycle (pedal system)
• screw heads change rotary motion to linear as it move in and out the thread hold