Analysis of Traction Forces in a Precision Traction Drive

Abstract

A theory for the shear stress between a rough elastic cylinder and a cylinder with a soft layer has been developed. The theory is based on a Fourier transform approach for the elasticity equations coupled with surface deflection equations for transient contacts. For thick layers (h > .001 in.) the shear stress on the surface approaches the shear of the layer alone. The elastic shear deflection (∼100 μin.) as a result of the tangential load is significant and increases if a surface layer such as a thin coating is added to one or both cylinders. The predicted interfacial shear stresses are considerably altered by surface roughness on uncoated surfaces and these effects are ameliorated by the addition of a thin soft surface coating.