A Parametric Study on the Vibration Transmissibility Characteristics of Transmission Ring Gear Structure

The vibratory energy from the ring gear resulting due to planet/ring gear dynamic forces is typically transmitted via structure-borne paths and is most evident in the range of 1-6000 Hz for automotive transmissions. In this paper, a comprehensive parametric force response analysis to study the vibration transmissibility characteristics of typical automotive planetary ring gears is performed. Effects of various geometrical parameters and number of planets on vibration transmissibility characteristics of ring gear structure are also studied. The planet/ring gear mesh forces are explicitly defined as externally applied force. Vibration transmissibility is defined by the spatial average acceleration response of the outer surface of the ring gear. The root mean square (RMS) value of these average responses is also predicted. The resulting trends are useful in identifying more robust design with lesser tendency towards the generation and transmissibility of excessive gear vibration and noise.