In belt drive, the velocity of two shafts can be varied by variation in diameter of pulley on which belt is mounted. But in chain or gear drive, the velocity of two shafts is varied by variation in the number of teeth on sprocket and gear, respectively. If an unstretched belt is mounted on the pulleys, the outer and inner faces of belt are subjected to tension and compression, respectively. In between the sections, there is a neutral section which has no tension or compression. Usually, this is considered at the half of thickness of the belt. The effective radius of rotation of a pulley is obtained by adding half the belt thickness to the radius of the pulley. A schematic diagram of belt drive is shown in Figure 15.1.
Figure 15.1 Belt Drive
Leave a Reply