【作者】 胡光军；

【导师】 李鸿光；

【作者基本信息】 上海交通大学 ， 机械设计及理论， 2011， 硕士

【摘要】 在大部分工程实际中,隔振广泛存在,它与我们的生活息息相关,对国民经济、人民生活都起着十分重要的作用。在传递路径中加入隔振装置,可以减小振源对于机械系统的影响,对保证民生起到了积极的作用。本文在总结前人对于隔振器设计经验的基础上,设计并实验验证了一种新型的非线性隔振器,该隔振器具有很好的通用性和良好的隔振效果。具体说来,本文的主要研究成果和结论如下:1、分析了斜薄壁梁结构,在竖直方向力的作用下的屈曲特性,通过两只斜向布置的薄壁梁与竖直方向弹簧结构的并联,在平衡位置附近,随着承载力的变化,位移的变化更显著且承载力的变化很小。2、分析了该装置在受谐波激励作用下的动力特性,即在工作区间具有较小的动刚度。通过与线性系统(竖直弹簧结构)的比较,发现该装置具有较低的共振频率,从而具有更大的隔振区间。同时该系统具有更小的位移传递率,可以有效隔离来自地基、底座等的振动,从而达到保护承载物的目的。3、通过该系统的动力学模型,结合静力学实验结果,推导出系统的动力学方程。由于薄壁梁结构的屈曲特性,使得并联结构的特性发生了改变,其振动可以用Duffing方程描述。通过谐波平衡法得到了系统的近似解,用Runge-Kutta法求得了数值解,分析了该系统可能出现的分岔、系统稳定性以及出现的跳跃现象。4、设计了该隔振器的验证样机,该样机具有可调节性,通过移动在滑槽中的支撑板,来调节水平方向上的距离,竖直方向的调节旋钮用来调节竖直方向的距离,可以扩大样机的承载能力,该样机具有通用性。5、在振动台上测试了线性系统和该隔振器的加速度传递率,实验结果与理论分析基本吻合。通过实验结果可知,该隔振器可使系统的固有频率减小,从而扩大隔振区间。更多还原

【Abstract】 In most practical engineering situation, vibration isolation is widespread, it plays a very important role in the national economy and our lives. Set a vibration isolator system in the transmission path, which can reduce vibration from the source to the receiver. This paper summarizes the previous accumulated design for the isolation, designs and analyzes a new type of nonlinear vibration isolator. The isolator has good versatility and good vibration isolation. Specifically, the paper’s main findings and conclusions are as follows:1、Analyze the oblique thin-walled beam structure’s buckling force characteristics in the vertical direction. By two thin diagonal layout thin-walled beam in parallel with the spring, and nearby the equilibrium position, it has such characteristic that with the capacity change, the displacement has more significant changes but the capacity force has small changes.2、Analyze the device’s dynamic characteristics under harmonic excitation, which has a smaller range of dynamic stiffness in the work region. Contrast with the linear system (vertical spring structure), it was found that the device has a low resonance frequency, which can enlarge the zone of vibration isolation. The system also has a smaller displacement transmissibility, and can effectively isolate the vibration from the ground, base and so on, to achieve the purpose of protecting the object.3、Through the dynamics model of the system, combined with static test results, the system’s dynamic equation is derived. Since the buckling force properties of thin-walled beam structure, the composite structure’s characteristic has changed, the vibration can be described by Duffing equation. By the harmonic balance method, the approximate solution can be obtained. By using Runge-Kutta solution, we can obtain exact solution. Analyze the dynamic system , it may occur such phenomenon that bifurcation ,system stability and the jumps.4、Design a isolator prototype to verify the theory. The model is adjustable. Moving the supportable plate in the chute to adjust the distance between the horizontal direction. Vertical direction of the adjustment knob is to adjust the vertical distance. The model can expand the carrying capacity, and it has versatility.5、The acceleration transmissibility of linear spring and the isolator are tested on vibration table test. Basically, experimental results are consistent with the theoretical analysis. Through experimental results, the isolator can reduce the natural frequency of the system, thereby expanding the range of vibration isolation.更多还原