Usually, power is transmitted from one shaft to another using belts, ropes, chains and gears. The salient features of them are as follows:
· Belts, ropes and chains square measure used wherever the space between the shafts is massive. For tiny distances, gears square measure most well-liked.
· Belts, ropes and chains are flexible types of connectors, i.e., they can be bent easily.
· The flexibility of belts and ropes is due to the property of their materials whereas chains have several small, rigid elements having relative motion between the two elements.
· Belts and ropes transmit power owing to friction between them and therefore the pulleys. If the ability transmitted exceeds the force of friction, the belt or rope slips over the pulley-block.
Owing to slipping and straining action, belts and ropes are not positive types of drives, i.e., their velocity ratios are not constant. While chains have a constant velocity.