Design of a Four Square Gear Tester for Noise and Vibration Measurements

摘要

The following report provides the design procedures for a Four Square Gear Tester. The primary purpose of the tester is to investigate noise generation in spur gears that result from two major sources: 1) Dynamic Loads and 2) Fluid Dynamics. The tester is designed to operate at 9000 rev/min with an applied shaft load of 301.11 in-1lbs. The design includes mechanical components, such as: 1) A dc shunt-wound electric motor (with SCR) which will allow testing to be performed over wide range of loading as well as speed, 2) A speed increasing mechanism consisting of pulleys and V-belts to provide the desired range of speed and torque, 3) Air bearings which are intended to minimize extraneous vibrations and provide good shaft alignment, 4) Flexible shaft couplings, with a low degree of dynamic imbalance and bending force transmission, to accommodate both angular and parallel shaft misalignment, 5) Gear mounts, also with low dynamic imbalance and with the required torque rating, to fasten the gears to the shaft; and 6) Precision ground steel shafts which will provide center-to-center accuracy and therefore minimize vibration. In addition a pressure-spray lubrication system was also selected to cool and lubricate the mating gear teeth.