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Wormgear Drives

Nomenclature K dynamic factor
v
K face load factor

a centre distance, mm K FN bending life factor
c clearance, mm K HN contact life factor
d reference diameter, mm L total contact length, mm
d a diameter of addendum circle, mm L h design life in hours, h
d diameter of dedendum circle, mm l span between two bearings, mm
f
E elasticmodulus,MPa m module, mm
F a axial force, N m a axial module, mm
F n normal force, N m n normal module, mm
F r radial force, or separating force, N m t transverse module, mm
F tangential force, or transmitted N number of cycles
t
force, N n rotational speed, rpm
f equivalent coefficient of friction P transmitted power, kW
v
I moment of inertia, mm 4 p a axial pitch, mm
i speed ratio, velocity ratio p transverse circular pitch, mm
t
j number of gear teeth meshing per p lead, mm
z
revolution q worm diameter factor, worm
K load factor quotient
K A application factor S housing external surface area, m 2

Analysis and Design of Machine Elements, First Edition. Wei Jiang.
© 2019 John Wiley & Sons Singapore Pte. Ltd. Published 2019 by John Wiley & Sons Singapore Pte. Ltd.
Companion website: www.wiley.com/go/Jiang/analysis_of_machine_elements