camshaft drivers "chain ,belts and gears "

Camshaft drivers it is a mechanical component that used for Power Transmission .

It may be belt ,chain or gear depending on engine design parameters like distance between cracnkshaft and camshaft,engine maximum speed,engine
torque and engine construction cost.

The belts are used to transmit power from
one shaft to another by mean of pulleys
which rotate at the same speed or at different
speeds .

The amount of power transmitted depends
upon the following factors :

1 -The velocity of the belt .
2 -The condition under which the belt is used.
3 -The arc of contact betwwen the belt and
   the smaller pulley .
4 -The tension under which the belt is placed
   on the pulleys .

The material used for belts must be strong , flexible , and durable .It must have a high coefficient of friction. It may be leather , cotton or fabric ,rubber ,or balata belts .Timing belts and chains are used
on overhead camshaft engines because the camshaft is far from the crankshaft .

In chain drive there is may be a hydrulic tensioner which is filled with oil under pressure .The chain
also uses guides to reduce noise and vibration , the chain are made up of rigid linkswhich are hinged together in order to provide the necessary flexibility for warping around the driving
" crankshaft " and driven " camshaft " wheel .

The chain are mostly used to transmit motion and power from one shaft to another , when the
distance between the centers of the shafts is short .The wheels have projecting teeth and fit into
the corredponding recess ,in the links of the chain .

Advantages and Disadvantages of chain drive over belt :

   Advantages

1 - The chain drive gives less load on the shafts .
2 - The chain drive gives a high transmission efficiency ( up to 98 percent ) .
3 - The chain drives may be used when the distance betwwen the shafts is less .
4 - The chains occupy less space in width than a belt drive , since the chains are made of metal.

Disadvantages

1 - The chain drive has velocity fluctuations especially when unduly stretched .
2 - The chain drive production cost is relatively high .
3 - The chain drive needs accurate mounting and careful maintenace .