Operating Behavior and Performance of Polymer Gears in Pulsator Tests

Abstract For designing gears reliable strength values are essential. The determination of strength values for the tooth root load-carrying capacity is usually based on experimental fatigue tests in a pulsator due to various advantages compared to back-to-back tests. In contrast to steel gears, it is currently unclear how polymer gears perform in the pulsator test and whether the pulsator test is suitable for determining the tooth root load-carrying capacity of such gears. Against this background, theoretical and experimental investigations on the operating behavior and fatigue life of POM gears were conducted and evaluated. Measurements on the tooth temperature under dynamic load provide insights into the thermal behavior of polymer gears, which must be considered due to the high-temperature dependency of the mechanical properties. Based on theoretical studies on the tooth root stress in the pulsator, S-N curves are determined and evaluated for different tooth temperatures revealing comparable tendencies to results from the back-to-back test in terms of damage pattern as well as service life.