CAE Analysis And Study Of High-speed Spindle Unit Of Test Bench

Gearbox performance directly influences overall performance of automobile. High quality test bench for transmission is the first condition to acquire accurate measurement data, and the high speed spindle unit is the core components in the test bench, spindle unit have a greater impact on the gearbox test results, so the research of spindle unit is of great significance.This article surveys the research status of motorized spindle unit, a common structure of spindle unit is selected, and the detail of the structure of the spindle unit is analyzed.Then, the static and dynamic mechanical analysis is carried out on the spindle unit, spindle unit stiffness is analyzed and the measures to improve the spindle stiffness are listed. In order to avoid any serious deformation or fracture on spindle unit caused by the resonance happens when unit natural frequency equals to external force frequency, the modal natural frequency of the spindle in each order, as well as its vibration mode and critical rotating speed, etc. are examined; frequency response characteristic near the first-order natural is examined, especially maximum deformation situation of key nodes on spindle front, middle and back end has been studied, the results shows that the structure is reasonable, but the critical speed is seriously excessiveThe structure is optimized based on the above analysis results, the span is fundamental for maximum stiffness of spindle unit, the optimal span is calculated. In order to eliminate the vibrations from axis misalignment, the main shaft is integrated with drive shaft, and the shaft sleeve is adopted. From static and dynamic analysis on optimized shaft sleeve and the shaft, there come the results of natural frequency, maximum stress, strain, and conclusion that dynamic state responds displacement. The analysis result shows that the critical speed of spindle unit reduce from36993r/min to25679r/min which can still meet the requirements of the test-bench maximum operating speed of6000r/min, and that the influence of axial vibration from displacement is eliminated.