含中间质量改进三参数隔振器动力学特性研究

通过在含X形机构非线性三参数隔振器中引入中间质量，提出一种改进三参数隔 振器并建立其理论模型 . 采用谐波平衡法得到隔振系统的稳态解析解，利用四阶龙格库塔法 和多体动力学软件 ADAMS验证其正确性 . 将力传递率作为评价隔振系统动态性能的技术指 标，与传统三参数隔振器以及含X形机构非线性三参数隔振器进行对比，结合工程实际，分别 给出3种类型隔振器在多频稳态激励下的时域位移响应，并进行对比研究. 分析了该隔振系统 的功率流特性以及能量特征，选择隔振系统部分关键设计参数进行影响因素分析 . 从动力吸 振器的角度，讨论了所提模型中非线性连接方式对其减隔振效果的影响. 计算结果表明，合理 选择中间质量可以在原隔振系统谐振频率附近形成一个反共振低谷，且系统固有频率向低频 移动，使隔振系统有效隔振频带变宽；相比于传统三参数隔振器和含X形机构非线性隔振器， 隔振系统在低频和高频的隔振性能均得到有效提升；通过力传递率评估设计参数，结果表明 各参数均存在最优值；将线性动力吸振器与接地X形机构连接，可进一步改善其减隔振效果.

Research on Dynamics Characteristics of Improved Three-parameter Isolator with Intermediate Mass

By introducing an intermediate-mass into the nonlinear three-parameter isolator with an X-shaped mechanism, an improved three-parameter isolator is proposed, and its theoretical model is established. The Har? monic Balance Method is used to obtain the steady-state analytical solution of the vibration isolation system, and the correctness is verified via the fourth order Runge-Kutta method and ADMAS. By using the force transmissibility as the indicator for evaluating the isolating performance, some comparisons are carried out among the proposed isolators. Meanwhile, according to the engineering application, the time-domain displacement responses of three types of isolat? ing systems under multi-frequency steady excitation are solved, and a comparative study is carried out, respectively. The vibration power flow and maximum kinetic energy are investigated, and some typical design parameters are se? lected and analyzed. At last, from the perspective of the vibration dynamic absorber, the effects of the nonlinear connection on the vibration suppressing performance are further discussed. The calculation results show that the natural frequency of the vibration isolator can be decreased after the intermediate mass is introduced into the system, the ef? fective vibration isolation frequency band of the vibration isolation system becomes wider, and an anti-resonance fre? quency is introduced at the original resonant frequency at the same time. Compared with the traditional threeparameter isolator and the nonlinear vibration isolator with an X-shaped mechanism, the vibration isolation perfor? mance of the developed isolator at both low and high frequencies is improved accordingly. In addition, the abovementioned all design parameters exist the optimal values when the force transmissibility of the nonlinear isolator is used as an evaluating index. Besides, the vibration suppressing performance of the vibration dynamic absorber with a grounded X-shaped mechanism is enhanced.