Paper 13: Choice of Tooth Type for High-Speed Gearing

The paper considers the pros and cons of spur, single, and double helical gearing. A detailed geometric analysis of the basic load capacities of helical and spur gears, respectively, leads to non-dimensional optimum tooth numbers for each type, having a constant ratio to one another irrespective of size and material. Helical gears are shown to require the same volume as spurs but relatively coarser teeth. Consideration of the possible dynamic effects of characteristic errors leads to the conclusion that spur gears are potentially superior for very high speed applications.