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Types of followers :

The followers may be classified as discussed below:

1. According to the surface in contact.

(a)Knife edge follower. When the contacting end of the follower has a sharp knife edge, it is called a knife edge follower.

(b) Roller follower. When the contacting end of the follower is a roller, it is called a roller follower.

Ans.: Given data; N1 = 80 rpm. N2 =150 rpm. D1= 600 mm. S = 4 % To find; D2 =?;

(i) Case I: Taking t = 5 mm. Velocity ratio, (V.R.) N2/N1 = (D1 + t)/ (D2 + t)

150/80 = (600 + 5)/ (D2 + 5)

Therefore, diameter of driven pulley D2 = 317.66 mm ~ 318mm

(ii) Case II: Assuming for belt thickness 5 mm and total slip of 4%. Velocity ratio, (V.R.) N2/N1 = {(D1 + t)/ (D2 + t)} × {1- (S/100)}

 150/80 = {(600 + 5) / (D2 + 5)} × {1- (4/100)

Therefore, diameter of driven pulley D2 = 304.76 mm ~ 305 mm

Applications- Automobiles like scooters, motorcycles, textile and paper industries, machine tools