Long Addendum Teeth Profile

We came by the knowledge of some competitor companies (agricultural tractor transmissions) use high addendum gear profiles like 1.35xM. Even the gears are have high numbers of teeth, the tips are very small unlike the normal profile.
I could not understand the benefits of such so-called high depth teeth and was looking for articles about it but could not find a good source. Are any of you familiar with such profile gears? Do you know the advantages of such profiles? Do they give better tooth root strength or flank safety?


It sounds like these are “extended addendum” gears. They typically use standard pitch centers, tooth thickness, and backlash. The benefit of this approach is higher contact ratio, smoother meshing, reduced noise, etc. The drawback is reduced tooth bending strength. The practical limit to extending the addendum is minimum acceptable width of the tooth top lands.

Don’t know the reason this particular type of gear geometry was used for your tractor transmission.

Above is a snippet.