Disk on disk test of gear pair power losses

Abstract

This paper presents the research of friction in gear pairs by using tribometer that provides diskon-disk contact. When gear teeth mesh, there is a combination of sliding friction and rolling friction, and in that, the values of sliding and rolling velocity are changed, as well as contact pressure. For the simulation of changes of velocities disk of various diameters with controlled tangential velocities are applied, and this enables a broad range of combinations of sliding velocity and rolling velocity. High and variable values of contact pressures that appear in real gear pairs are realized by the combination of variable values of normal load and dimensions (diameter and width) of the disks. Friction coefficient is used as the indicator of friction magnitude. By knowing the changes of contact conditions and friction coefficient during the meshing of one pair of gear teeth it is possible to determine total gear pair power losses. Disk-on-disk contact provides the most realistic simulation of gear teeth meshing.