Experiment Of A Rubber And Wire-cable Composite Vibration Isolator

When the strength of vibration source in the real project is more and more severity, the harm of vibration and noise becomes very important. To reduce and control the level of vibration and noise, vibration control technology has been researched and used widely. Based on the studying of the isolation technology and analysing of the advantage and disadvantage of common isolator, a new rubber wire-cable composite vibration isolator has been designed in this paper. It has not only wider vibration isolation frequency range, which can restrain the high and low frequency vibration, but also larger carrying capacity, which can improve the isolation performance at the resonance area.Since the rubber wire-cable composite vibration isolator has the compound characteristics of friction damping and viscoelasticity damping, the mixed type model is chosen to establish the dynamic model of the composite vibration isolator. According to the nonlinear characteristics of the composite vibration isolator, the equivalent linear method and harmonic balance method are used to obtain the frequency response equation of the composite vibration isolator.The test platform and vibration test system are designed basing on the electrodynamic shaker. A series of systematic tests is performed to study the transmissibility and the dynamic characteristics curves of the composite vibration isolator. From the test data of isolation performance, the influences of different isolation mass, exciting amplitude and rubber material on the transmissibility of the composite vibration isolator are analysed. The studies show that the rubber wire-cable composite vibration isolator has wider carrying capacity and also has good isolation performance on different exciting amplitude. From the tests of dynamic characteristics of the rubber wire-cable composite vibration isolator, the influences of different exciting amplitude and exciting frequency on the dynamic characteristics of the composite vibration isolator are analysed. It shows that the rubber wire-cable composite vibration isolator's dynamic stiffness and damping has strong non-linear characteristics. The comparison of the dynamic characteristics curves of wire-cable and composite isolators shows that the composite vibration isolator can dissipate more vibration energy and the performance is better than the wire-cable isolator at the resonance area.The influences of different rubber materials (natural rubber and EPDM rubber) on the transmissibility of composite vibration isolator are analysed by using the test platform. The dynamic hysteresis loop curves of natural and EPDM rubber composite isolators at the resonance area are compared. It is verified that the EPDM rubber which has a larger damping has a little different influence on the isolation characteristics with that of the natural rubber. The results show that the natural rubber vibration isolation is enough to achieve a good isolation performance.