不同型线柔性轴承的性能分析及比较

柔性轴承的应力分布及动态刚度特性对低温制冷机的整体可靠性尤为重要.以最大应力值、轴向刚度、径轴向刚度比为性能指标,对新设计的费马型线柔性轴承和其他两种柔性轴承进行对比研究.通过有限元分析,对比了三者之间应力分布、应力变化及刚度变化特性.设计制作了这3种不同型线的柔性轴承,并测试了3种柔性轴承的径轴向刚度,结果显示:费马型线柔性轴承的径轴向刚度之比最大,牛津型柔性轴承的径向刚度最小;费马柔性轴承的应力值最大,但最大应力值小于材料的疲劳应力,因此费马型线的柔性轴承在性能上优于其他两种柔性轴承.

Performance analysis and comparison of flexure bearings with different profile lines

It is crucial to analyze the performances of flexure bearings which would influence the overall reliability of cryocoolers. The performance parameters of flexure bearings include the stress distribution, axial stiffness, and dynamic radial stiffness and so on. The Fermat flexure bearing was designed, which was analyzed and compared with the other two kinds of flexure bearings in the above aspects by finite element method (FEM) and experimental study. The three flexure bearings were fabricated, and the axial stiffness and dynamic radial stiffness were tested individually. The testing results agree well with the finite element analysis (FEA) results. They indicate that the Fermat flexure bearing owns the highest stiffness ratio. The radial stiffness of the Oxford flexure bearing is minimum. The maximum stress value of the Fermat flexure is highest among the three flexures, but which falls well below the material fatigue limit stress. Hence, the Fermat flexure bearing is superior to other two kinds of flexure bearings.