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Contact Ratio Calculator
Calculates e_alpha (profile) and e_beta (overlap) with ISO/DIN full-depth assumptions and returns total contact ratio.
Contact Ratio Calculator
Computes e_alpha (profile) and e_beta (overlap) for ISO/DIN standard full-depth (ha* ~ 1, hf* ~ 1.25). For beta = 0, helix contribution is zero.
Profile contact ratio e_alpha1.573
Overlap ratio e_beta1.442
Total contact ratio e3.014
Transverse module m_t [mm]2.071
Transverse pressure angle α_t [deg]20.65
Center distance a [mm]74.54
In the e_alpha formula, base pitch p_b = π·m_t·cos(α_t) is used. e_beta = b*sin(β)/(π·mn); for beta = 0, e_beta = 0. ha* = 1 (standard addendum). Root safety should be checked separately for hf* ~ 1.25.
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