Analysis and experiment of a magnetic levitation vibration isolator with the positive stiffness and the negative one in parallel
LI Qiang1, XU Dengfeng2, LI Lin1，Wei Shaoyan2
1. Information and Engineering school, Wuchang University of Technology, Wuhan 430223, Hubei, China
2. Department of Mechanical Engneering, Tsinghua University, Beijing, 100084 China
Abstract：In order to develop a new type of vibration isolator for a miniature instrument, a magnetic levitation vibration isolator (MLVI) with a permanent magnetic spring (PMS) in combination with rubber ligaments was proposed, in which, the magnetic spring provides the positive stiffness and the rubber ligament supplies the negative one.For studying the vibration isolation performance of the isolator, an analytical model of the stretched force of the rubber ligament was built and validated by an experiment, which proves that the analytical expression is efficient.Then an analytical expression of the stiffness of the rubber ligament was deduced by the derivative of the stretch force to the vertical deformation of the rubber ligament.As a case study of the isolator, the dynamic characteristic of the isolator was analyzed.A vibration isolator table was constructed to verify the vibration isolation performance of the isolator.The transmissibility curves of isolator were calculated and tested by the instrument.The experimental results show that there is a good agreement between the measured transmissibility and the calculated ones, which proves that the negative stiffness can partially offset the positive one.The main advantages of the isolator is when the load capacity of the isolator achieves the maximum value with the lowest stiffness, the isolator obtains the lowest natural frequency.Compared with the experimental data of the permanent magnet spring and the MLVI, it demonstrates that it is a valid method to explore the new MLVI.
李强1，徐登峰2，李林1，魏绍炎1. 基于正负刚度并联永磁隔振器的隔振性能分析及实验验证[J]. 振动与冲击, 2019, 38(16): 100-107.
LI Qiang1, XU Dengfeng2, LI Lin1，Wei Shaoyan2. Analysis and experiment of a magnetic levitation vibration isolator with the positive stiffness and the negative one in parallel. JOURNAL OF VIBRATION AND SHOCK, 2019, 38(16): 100-107.
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