Optimization Design and Horizontal Stiffness Analysis of Three-wire Pendulum Mechanism of Air Spring Vibration Isolator

Vibration will affect the performance of high-precision equipment, so it is necessary for the research of vibration isolators. This paper takes air spring vibration isolators applied to high-precision chip testing equipment as the research object, and designs a three-wire pendulum mechanism with a ball hinge structure. The ball-hinge structure can reduce the horizontal stiffness of the three-wire pendulum mechanism, thereby improving the isolation performance of the vibration isolator. Then the mathematical model of the three-wire pendulum mechanism is established, and the factors that affect the horizontal stiffness of the three-wire pendulum mechanism when subjected to slight vibration are obtained through theoretical analysis. Finally, ANSYS Workbench is used to carry out the finite element simulation analysis, which verifies the results of the theoretical analysis. Reducing the diameter of the fixed plate of the swing rod can reduce the horizontal stiffness of the swing mechanism. When the diameter of the fixed plate of the swing rod is reduced by 2%, the horizontal rigidity is reduced by 5.86%; Increasing the diameter of the wobble plate can reduce the horizontal stiffness of the pendulum mechanism. When the diameter of the wobble plate is increased by 2%, the horizontal stiffness is reduced by 4.96%; Increasing the distance between the fixed plate of the swing rod and the swing plate can reduce the horizontal stiffness of the swing mechanism. When the distance between the fixed plate of the swing rod and the swing plate is increased by 2%, the horizontal rigidity is reduced by 3.99%. It provides a basis for the subsequent research on vibration isolators using the three-wire pendulum mechanism.