Authors

Abstract

Gearing is one of the most critical components in mechanical power transmission
systems. This work investigates the characteristics of an Involute gear system
including contact stresses. Current methods of calculating spur gear (Non-linear
Analysis), contact stress using Hertz’s equation, which were originally derived for
contact between two cylinders. To enable the investigation of contact problems with
Finite Element Method (FEM), the stiffness relationship between the two contacts
areas is usually established through a spring placed between the two contacting areas.
This can be achieved by inserting a contact element placed in between the two areas
where contact occurs. A computer program was built up using (MATLAB 6.5). The
results of the two dimensional FEM analyses from ANSYS are presented. These
stresses are compared with the theoretical values (Hertz’s equations). Both results
agree very well. This indicates that the Finite Element Method(FEM) model is
accurate. The results of contact stress analysis indicates that increasing the geometrical
parameters (Pressure angle, number of teeth and module) lead to improve the tooth
contact stress, with the contact position, because the increasing of the geometrical
parameters will results in an increase of the tooth stiffness which leads to decrease the
tooth contact stress.

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