Low frequency vibration isolator with adjustable configurative parameter

Abstract This paper will develop a low frequency vibration isolator with a mechanism for adjusting the configurative parameter (shorted LFVIM). This isolator offers a large isolation range, ensures a load bearing capacity and maintains the isolation effectiveness when the isolated weight is replaced. This way, adjustment of its configurative parameters is indispensable in accordance with self weight of newly placed isolated object. This will be realized by introducing a mechanism that enables easy and quick adjustment of the configurative parameters of the LFVIM. Then, the effects of the parameters including the dynamic stiffness at the desirable static equilibrium position, the self-weight of the isolated object and the slope of the dynamic stiffness curve on the steady state response as well as the isolation effectiveness of LFVIM are clearly analysed. A seventh order approximate polynomial function is used to explore the effects of these parameters. Then, the normal form method (NF) is employed to predict the frequency response curve of the LFVIM at the steady state. The simulation results show that the LFVIM can offer significant isolation advantages. Besides, these results furnish a useful insight for the design and analysis of the LFVIM.

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