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Constant velocity ratio

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Involute

InvoluteInvolute : (r cosUU rsinUrsinU U r cosU )

U

r

UrU

r cosU

r sinUUr cosU

Ur sinU

sin coscos cos sin sin

sin sin cos coscos sin

dy dr r

dy r r rd ddx ddx r r r

r r

d d

U U UU U U U UU U

U U U U UU U U

U U

! ! ! !

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Involute Properties

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Proofs

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Involute action

U R

Ur

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Terminology

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Terminology

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Involute and Rack

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Rules and Standards

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Tooth thickness

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Tooth thickness

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Interference and Undercutting

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Interference and Undercutting

Addendum : a

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Interference and Undercutting

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Contact ratio

AxialcontactratioAxialcontactratio

Transverse contactratioTransverse contactratio

Totalcontact ratioTotalcontact ratio

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Manufacturing

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Manufacturing