Mixed EHL Analysis of the Variable Torque Slipping Clutch With Skewed Rollers

In this paper, a mixed EHL analysis is presented for the variable torque slipping clutch with skewed rollers. It is characterized by a finite spatial curve contact and two dimensional rolling and slipping. A combination of the average roughness Reynolds equation developed by Patir and Cheng and the pressure-compliance relationship of roughness contact developed by Greenwood and Tripp is adopted to combine the effect of surface roughness in the lubrication. The average roughness Reynolds equation is extended to involve the two dimensional rolling and slipping while the pressure dependence of both the density and viscosity are considered. Based on the numerical techniques of the FEM discretization and relaxation iteration, the average roughness Reynolds equation is solved simultaneously with the GT contact pressure-compliance relationship under the equilibrium condition of the elements of the slipping clutch. The hydrodynamic and asperity contact pressures are then calculated and the interactions and mutual influences between these two kinds of pressures are shown. In addition, the influences of the rotation speed on the resistant torque are investigated both theoretically and experimentally. Concurring agreements are found between the theoretical and experimental data.