Question

A 20-tooth spur pinion has a diametral pitch of 8, runs at 1200 rev/min, and drives a gear at a speed of 400 rev/min. Find the number of teeth on the gear and the theoretical center-to-center distance

Answer 1

number of teeth = 60 teeth

center to center distance = 5 in

Step-by-step explanation:

Given data

diametral pitch p = 8

no of teeth pinion n = 20

speed s = 1200 rev /min

gear speed Sg= 400 rev/min

to find out

number of teeth in gear and distance

solution

we will find here number of teeth in gear by formula that is

number of teeth = p×dg ............1

dg = s/sg × dp

and dp = 20/8 = 2.5

so

dg = s/sg × dp

dg = 1200/ 400 × 2.5

dg = 7.5

so from equation 1

number of teeth = p×dg

number of teeth = 8 × 7.5

number of teeth = 60 teeth

and

center to center distance will be calculate by formula

center to center distance = ( dp + dg ) / 2

center to center distance = ( 2.5 + 7.5 ) / 2

center to center distance = 5 in