BELT

 The belt or ropes are used to transmit power from one shaft to another shaft by means of pulleys which rotate at the same speed or at different speed.

 Types of belt drives.

 1.     Light drives: belt speed upto10m/s

 2.     Medium drives: speed 10m/s to22m/s

 3.     Heavy drives :Speed ove r22m/s

Types of belt

 1.Flat belt

2.V- belt

3.Circular belt or rope

Type of flat belt drives

 Open belt drive

 Cross belt drive

 Quarter turn belt drive

 Belt drive with idler pulley

 Velocity of belt drive

It is the ratio between the velocies of the driver and follower or driven.

d₁      =       diameter of the driver

d₂      =       diameter of the follower

N₁      =       Speed of the driver r.p.m

N₂      =       Speed of the driven r.p.m

Let r1 and r1  =    Radii of the larger or smaller pulleys

 x         =Distance between the centres of the two pulleys

 L   =       Total length of the belt.

 Length of an open belt drive

 Length of the cross belt drive.

  Power transmitted by a belt

T₁ and T₂    =       Tensions in the tight and slack side of the belt respectively N

r1 and r1     =       Radii of the larger or smaller pulleys

v        =Velocity of the belt m/s

Power         =       (T1-T2)v W

Belt and rope drives: