Consider the following characteristics :
1. Small interference
2. Strong tooth
3. Low production cost
4. Gear with small number teeth.
Those characteristics which are applicable to stub 20° in volute system would include :
Option (A)
1 alone
Option (B)
2, 3 and 4
1, 2 and 3
1, 2, 3 and 4
Correct Option:
Question Solution:
20° stub tooth involute:
Stub mean 20% less working depth than full depth gear so addendum is shorted (small interference is stub system). The tooth becomes stronger as the level arm of bending moment on tooth is reduced. Machining cost is less as compared to full depth system as less metal must be cut away minimum no of teeth on pinion to avoid interference is 14.