Dynamic Loads on Spur Gear Teeth at High Speed : Influence of the Pressure Angle Errors and Comparison between the Reduction Gears and the Speed-up Gears

Abstract

Dynamic loads on spur gear teeth are measured by a high speed gear testing machine at a periphery velocity of 80 m/sec and below. The ground gears (some of them have pressure angleerrors) are tested as reduction gears and also as speed-up gears respectively. The maximum dynamic loads occur at a critical speed, at which the meshing frequency is equal to the natural frequency of the vibratory system consisting of a pinion, a gear and a combined tooth stiffness. At a speed over the critical one, the magnitude of the dynamic load approaches a certain constant which is determined by the tooth errors. When the errors are repeated in each meshing as in these cases, the dynamic loads of the gear tested as a follower are nearly equal to the ones tested as a driver.