采用摆线包络线旋转曲面轨道滚珠式动力吸振器制振特性

Vibration isolation characteristic of a ball type of dynamic vibration absorber with an orbit formed due to revolution of a cycloidal envelope

针对基于单摆原理的球面滚道、滚珠式多向动力吸振器中,因吸振器恢复力的非线性导致吸振器固有频率随主系统外激励幅值变化、吸振系统参数偏离最优设计值问题,提出采用摆线包络线旋转曲面作为轨道面,与滚珠组合成动力吸振器方案。该吸振器最大优点为作用于主系统的激励幅值不影响吸振器固有频率、系统参数能始终保持最优设计值、能有效对多方向共振响应进行制振,结构简单,性能可靠。并据定点理论,通过分析及数值模拟等研究动力吸振器参数最优设计。

Dynamic vibration absorbers are extensively used to suppress high amplitude resonance responses of machines or structures near their natural frequencies extensively. For a ball type multi-direction vibration isolator with a spherical orbit based on the theory of a single pendulum, its isolation system parameters deviate from the optimized design values because the nonlinear character of the restoring force often causes its natural frequency changing with the amplitude of external excitation force acting on the main system. A new type of dynamic vibration absorber was proposed here, its orbit was formed due to revolution of a cycloidal envelope and a ball is in the cavity. It was shown that the absorber has an excellent advantage that the external force acting on the main system has no influence on the natural frequency of the isolation system, so the parameters of the isolation system can always keep the optimized design values and suppress the resonance response in multi-direction effectively; in addition, the isolator is simple and reliable. According to the fixed- point theory, the parameters to be optimized were studied through the theoretical analysis and numerical simulation.