BE analysis of shaft–hub couplings with polygonal profiles

In the mechanical transmission field, shaft–hub couplings with polygonal profiles play an interesting role because of their characteristics of self-alignment, lack of projecting elements (responsible for high stress concentration) and constructive compactness. Other characteristics, like transmission of static/oscillating torque load, even with small overall dimensions, and easy hub interchangeability, make such couplings competitive with the traditional ones based on keys and splined shafts. This work concerns a study on steel made polygonal couplings, with trochoidal three-lobe profile, and is aimed to highlight the contact stress and strain state of shaft–hub interface, with reference to particular profile geometric parameters. From Mechnik’s and Kollmann’s works, in which the analysis was performed by the Finite Element Method, this work develops a CAD/CAE methodology for coupling design, oriented to an efficient integration between CAD systems and BEM solvers. The stress analysis is carried out with a Boundary Element code (BEASY) well suited for this kind of contact problems while coupling geometric model is made by Pro/Engineer, a solid parametric modeller.