scope:

Military tracked vehicles demand a very compact transmission to meet mobility requirements. Some of the desirable characteristics of these transmissions include: increased rating, improved power to weight ratio, low operating noise and vibration, and reduced weight. To achieve all or some of these characteristics, it is has been decided to apply a High Contact Ratio (HCR) spur gearing concept which will improve load carrying capacity, lower vibration, and reduce noise. Similar to helical gears, the load in HCR gearing is shared by minimum two pair of teeth. Therefore, load sharing analysis was conducted on Normal Contact Ratio (NCR) gearing used in sun - planet gears of an existing drive. This paper deals with analysis of load sharing of individual teeth in mesh for different load conditions throughout the profile for both sun and planet gears of NCR/HCR gearing using Finite Element Analysis. Also, the paper reveals the variation of bending stress and deflection along the profile of both gearing designs.