Profile Shift (Addendum Modification)
x-coefficients → modified center distance, working pressure angle, tip/root diameters, contact ratio
Module — m
Pinion Teeth — z₁
teeth
Gear Teeth — z₂
teeth
Pressure Angle — α
Face Width — b
mm
Pinion Shift Coefficient — x₁
Gear Shift Coefficient — x₂
Positive shift (x > 0) strengthens the tooth and avoids undercut. Standard gears use x = 0. Min to avoid undercut at 20°: x_min = (17 − z) / 17.
Undercut Check
Min Shift Pinion x₁_min
—
Min Shift Gear x₂_min
—
Modified Mesh
Sum of Shifts x₁ + x₂
—
Working Pressure Angle αw
— °
Standard Centre Distance a
— mm
Modified Centre Distance a′
— mm
Centre Distance Change Δa
— mm
Pinion Dimensions
Pitch Circle Dia d₁
— mm
Tip Diameter da₁
— mm
Root Diameter df₁
— mm
Base Circle db₁
— mm
Gear Dimensions
Pitch Circle Dia d₂
— mm
Tip Diameter da₂
— mm
Root Diameter df₂
— mm
Base Circle db₂
— mm
Contact Ratio
Contact Ratio εα
—