Belt Forces and Surface Model for a Cloth-Backed and a Rubber-Backed Flat Belt

The normal and tangential belt forces for two types of flat belts are measured and compared. From friction theory, it was assumed that the actual contact area A_a is proportional to normal pressure p; i.e., A_aαpⁿ. For a flat belt with cloth backing, the n =2/3 is obtained for the belt surface contact model. For a flat belt with rubber backing, which is used for power transmission, the n = 0.9 to 1.0 is suggested as a surface model. Different friction surfaces, construction materials, and geometries for the two belts resulted in different contact patterns and different friction characteristics.