Upon the efficiency of gear transmissions

The work proposes an experimental method and device for finding the efficiency of the spur gear mechanism. A simple device that can measure the work lost by friction only in teeth contacts was constructed. The test rig was designed to ensure measurements for two configurations with the same inertial characteristics but for different gear friction conditions. The principle is based on the difference of energy losses for the two mounting cases that provides the energy lost by friction between flanks. Recording the variation of the decreasing rotational speed for the case of constant actuating torque, the frictional losses can be deduced. The values of the efficiency obtained are smaller than in literature. The method is simple and rapid and the experimental results validate the theoretical model.