文档介绍：Available online at hanism
and
Machine Theory
Mechanism and Machine Theory 43 (2008) 1557–1584
ate/mechmt
Effect of addendum on contact strength, bending strength
and basic performance parameters of a pair of spur gears
Shuting Li *
Nabtesco Co. Ltd., Oak-hills No. 202, Heki-cho 7028-2, TSU-shi, Mie-ken 514-1138, Japan
Received 15 July 2007; received in revised form 15 December 2007; accepted 26 December 2007
Available online 13 February 2008
Abstract
This paper investigates effect of addendum on tooth contact strength, bending strength and basic performance param-
eters of spur gears. Face-contact model of teeth, mathematical programming method (MPM) and three-dimensional (3D),
finite element method (FEM) are used together to conduct loaded tooth contact analyses (LTCA), deformation and stress
calculations of spur gears with different addendums and contact ratios. Tooth load, load-sharing rate, contact stress, root
bending stress, transmission error and mesh stiffness of the spur gears are analyzed. Effects of addendum and contact ratio
on gear strength and basic performance parameters are also discussed.
It is found that contact stress distributed on tooth surface along the profile is asymmetrical around the geometrical con-
tact point of the gears when the geometrical contact point is far away from the pitch point, especially at the tip or root
contacts. The maximum contact stress is also not exactly at the geometrical contact point. Hertz formula can only calculate
the tooth contact stress approximately. FEM can be used to conduct precise analysis of the tooth contact stress.
It is also found that increment of addendum can increase number of contact teeth, then this increment can reduce tooth
contact stress and root bending stress, generally speaking. But this increment also makes the tooth depth long and lets the
tooth be deformed easily. So, this increment can reduce tooth contact stress, but there is no guarantee that this increm