Stacked plate - elastomer system

The suspension-spring vibration isolation system has a disadvantage It is large. Gerber et al. (1985) developed a vibration isolation system using a stack of metal plates separated by rubber pieces. It was first used in the pocket-size STM, which will be described in Section 13.1. By increasing the number of metal plates, reasonably good vibration isolation can be achieved in a modest space (see Fig. 10.8). 

An analysis of the transfer function of this system can be made using the matrix method described by Okano et al. (1987). However, the stiffness of the rubber pieces is highly nonlinear. Okano et al. (1987) found that the measured transfer function does not fit theoretical predictions based on a constant stiffness. A nonlinear elastic behavior must be taken into account. Another problem with the metal-stack system is that the resonance frequency is around 

10 Hz because of its small size. The isolation is effective only for vibrations with relatively high frequencies ( 50 Hz). To suppress the low-frequency vibrations, an additional suspension-spring stage is needed. 

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Vibration isolation 237—250 critical damping 239 pneumatic systems 250 quality factor, Q 239 resonance excitation 241 stacked plate-elastomer system 249 transfer function 240 Virus 341 Viton 250, 270, 272 Voltage-dependent imaging 16, 17 Si(lOO) 17 Si(lll)-2X1 16 Volterra equation 310 Vortex 334 W... 

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