New software (e.g., NREL’s Drivetrain toolbox) generates gears not based on standard modules, but on stress-flow optimization. The generator modifies the helix angle dynamically across the face width (bi-directional crowning) to reduce edge loading under deflection.
The generator uses these relationships to plot the tooth root, working profile, and tip diameter. The lead (L) of the helix—how far the tooth travels axially in one rotation—is calculated as: [ L = \frac{\pi \cdot d_p}{\tan(\beta)} ]
Create a Right-Hand Helical Gear, Module 2, 30 Teeth, Helix Angle 25°, Pressure Angle 20°.