Study on the Bending Vibration of a Two-Piece Propeller Shaft for 4WD Driveline

摘要

Currently, four wheel drive (4WD) system is widely used in Sports Utility Vehicle (SUV) due to the increasing demand of fuel efficiency and dynamic performance by customers. However, propeller shaft consisting of different universal joints and tubes on 4WD vehicle easily induces low frequency bending vibration. This paper analyzes the characteristics of driveline bending vibration of a 4WD vehicle and provides control methods to reduce the low frequency vibration caused by propeller shaft bending resonances. Firstly, the driveline bending vibration model of the 4WD vehicle is established using FEA method and the natural frequencies are calculated. Secondly, the influence parameters, such as universal joint, relative length of two-piece propeller shaft, and tube diameters, on bending frequencies are analyzed by both FEA analysis and physical testing. Thirdly, the bending vibration responses for several propeller shafts with different lengths and diameters are predicted by unit force input at PTU shaft output. Finally, the control methods to reduce propeller shaft bending vibration are proposed. The analysis results are validated by testing and both reach good consistency.