Abstract:Based on the rattle characteristic of gear pair and transmission assembly, a study on establishing quantitative evaluation indexes of rattle characteristic for transmissions is conducted. The test is conducted in a semi-anechoic laboratory. The experimental device is mainly used to test the vibration and noise of the transmission. The drive motor is a high dynamic permanent magnet motor with special torque-rotation characteristics, which can be used to simulate the gas pressure of internal combustion engine and reciprocating inertial force of piston, in order to realize the output torque characteristics of the engine. The rattle characteristic curves of gear pair and transmission assembly are obtained by calculating the standard deviation of velocity difference and energy superposition processing to transmission case vibration data, respectively. The evaluation index vectors of the rattle characteristic are built up by extracting the characteristic parameters from two characteristic curves. They are used for rattle problem analysis of a five speed transmission, and for comparative evaluation to the rattle performance of the transmission before and after optimization. The evaluation results show a good agreement with the subjective evaluation.