Page 83 - Gear Technology Solutions

5.9 Summary

Root interference is a common problem not only for straight bevel gears but also
for cylindrical gears as well as for spiral bevel and hypoid gears. Interferences are
often difficult to detect but their influence on the performance of a gearset is signif-
icant. Interference lines and increased single flank errors are in many cases only
present if deflections under load are applied. Even the smallest interference leads
to noisy operation and often causes flank surface damage or tooth fracture.

The Gleason Dimension Sheet shows what the maximally permissible blade edge
radii are. The gear engineer who designs a new bevel gearset should select the
smallest value of the three different limit radii for the cutter edge radius. In addition,
attention has to be paid to the top-root clearance. If this value is too small, then an
interference will still occur, although the blade edge radii have been chosen cor-
rectly.

5.10 Literature

[1] Stadtfeld, H.J. “Gleason Bevel Gear Technology - The Science of Gear Engi-
neering and Modern Methods for Angular Transmissions”, Com-
pany Publication, The Gleason Works, Rochester, New York,
2014, ISBN 978-0-615-96492-8, Pages 235 to 239

[2] Stadtfeld, H.J. “Practical Gear Engineering - Answers to common Gear Manufac-
turing Questions” Company Publication, The Gleason Works,
Rochester, New York, 2019, ISBN 978-0-578-46376-6, Pages:
107 to 116

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