Design and Assessment of an Antibacklash Single Roller Enveloping Hourglass Worm Gear 2019-01-1071

A theoretical and experimental analysis is conducted to study the influences of key design parameters on the backlash of the roller enveloping hourglass worm gear. Two equations, the gear engagement equation and the tooth profile equation have been derived and represented in terms of four key parameters arising from the backlash of the worm gear by applying the gear meshing theory. Based on the derived equations, an efficient approach for reducing or eliminating the backlash of such a novel warm gear is developed. Specifically, the influences of center distance, roller radius, transmission ratio, and the radius of base circle on the contact curves and the tooth profile have been systematically investigated through numerical analysis, modeling and simulation. Next, a roller enveloping hourglass worm gear is manufactured and used for assessing the efficiency of the developed method in reducing and/or eliminating the backlash. Results from the tooth contact analysis (TCA) and the experiment indicate that the proposed tooth profile design approach can effectively reduce the backlash therefore improving the performance of the roller enveloping hourglass worm gear.