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Mechanisms Cam and Follower
Cam and Follower
Cam and Follower • The cam and follower is a device which can convert rotary motion (circular motion) into linear motion (movement in a straight line) Cam Follower
Cam and Follower follower The cam can have various shapes. These are know as cam profiles. Cam
Pear shaped Cams an followers are used in car engines to control the movements of the inlet and exhaust valves.
Snail/Drop Cam Snail or drop cams have the appearance of a snail shell. 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. Snail cams with notches are used as chain tensioners in modern bicycles
Eccentric Cams Eccentric cams are used on many modern bicycles. During a bicycle race, the cyclists sometimes get flat or punctured tyres. They then have to take the wheel off to remove the tyre before they can fix the tyre. This takes a lot of time, and they'll struggle to catch up with the other cyclists again. Many years ago, engineers designed a mechanism with which you can quickly take a wheel off a bicycle, without using any tools. This is called a "quick release" mechanism. Today, more expensive bicycles use quick release mechanisms on their wheels. They also use a quick release mechanism to make it quick and easy to change the height of the saddle. The photos below and on the right show a quick release mechanism uses an eccentric cam to lock the saddle at the correct height.
Eccentric Cams A quick-release mechanism is used to clamp the seat post to the frame of this bicycle.
Cam and Follower A follower is a component which is designed to move up and down as it follows the edge of the cam Knife edge Follower Flat foot follower Off set follower Roller follower