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.