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Design of Safety Factor for Slip of Half-toroidal Variator by Dynamic Behavior Analysis

Article of Honda R&D Technical Review Vol.29 No.2


In order to determine the power transmission characteristics of half-toroidal variators, a dynamic behavior analysis technique was developed to predict the traction coefficient. The approach uses the finite element method so that the elastic deformation of the parts in actual operation can be reproduced in variator modeling. As the technique reflects the shear characteristics of the traction fluid on the traction surface, frictional force was identified based on a four-roller test and used for the contact surface in the behavior analysis model. To control ratios, feedback control was applied based on the shifting mechanism of the toroidal variator. Using this technique to quantitatively predict the change in slip rate for the traction coefficient of the half-toroidal variator allows for the corresponding safety factor to be established.


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Author (organization or company)

Masahiro TANAKA(Automobile R&D Center)、Toshihiro SAITO(Automobile R&D Center)、Koji MIYAMOTO(ITO CORP.)

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