Reverted Gear Train

If axes of the first and the last wheels of a compound gear coincide, it is called reverted gear train.

Example 15.9: In a reverted gear train, speed ratio is 10 as shown in Figure 15.26. The module of gear 1 and 4 is 3 mm and module of gear 2 and 3 is 2 mm. Calculate the number of teeth on gears.

Figure 15.26 Reverted Gear Train

Solution:

The speed radio is inverse of teeth ratio

i.e., 

Distance between shaft is 180 mm