Based on the fixed end beam calculation. Anticipates that the total circumferential force can only be carried by one tooth. Adds an extra contact check.
Allowable load
F all = π c min b w ζ m en μ≥ F t
where:
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c min = min (c b , c c ) |
minimum tooth allowable stress |
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b w |
operating facewidth |
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m en |
normal module at end (normal diametral pitch at end inverse value) |
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| μ |
factor of dependence on the precision degree (material property) |
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F t |
circumferential force acting on the teeth |
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width factor |
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where: |
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K = 1.4 for straight teeth, 1.25 for helical teeth |
Safety factor
S = F all / F t
Bending factor
where:
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σ Ab |
allowable stress in bending (material property) |
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r b |
speed bending factor (table value) |
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y b |
shape bending factor (table value) |
Contact factor
where:
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σ Ac |
allowable stress in contact (material property) |
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r c |
speed pressure factor (material property) |
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y c |
shape pressure factor (material property) |
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size factor |
