固有频率连续可调的动力吸振器设计研究

Design and Research of a Dynamic Vibration Absorber with Continuous Adjustable Natural Frequency

振动通常会对周围的人和物造成危害,为避免此危害,在振动体上安装无阻尼动力吸振器是有效控制振动的措施之一。而无阻尼动力吸振器的使用条件是其固有频率需要与振动体的激振频率相等或极为接近。文章提出一种动力吸振器固有频率连续可调的新结构和新理论。在前、后无盖的钢制长方体框架内部,对称安装两根斜置弹簧,两弹簧的上端沿框架上表面可以对称移动,两弹簧下端悬挂同一球形质量块。从理论上确立了弹簧上端的水平位移与弹簧竖向夹角、弹簧的竖向总刚度与弹簧竖向夹角、弹簧的竖向总刚度与弹簧上端的水平位移之间的定量变化关系,并对该动力吸振器的振动控制效果进行实验验证,以期为动力吸振器的设计提供新参考。

Vibrations usually cause harm to the people and objects around them.However,installing non-damped dynamic vibration absorber on the vibration body is one of the measures to effectively control the vibration.Service condition for a non-damped dynamic vibration absorber is that its natural frequency needs to be equal to or very close to the excitation frequency of the vibrating body.In this article,a new structure and theory for a dynamic vibration absorber with continuous adjustable natural frequency is proposed.Inside the steel rectangular frame without covers at the front and rear,two diagonal springs are symmetrically installed.The upper ends of two springs can be moved symmetrically along the upper surface of the frame,and the same spherical mass block is suspended from the lower ends of two springs.Quantitative change relationships between horizontal displacement of upper end of spring and angle between spring and vertical direction,between total vertical stiffness of springs and angle between spring and vertical direction,between total vertical stiffness of springs and horizontal displacement of upper end of spring are established theoretically.Meanwhile,the vibration control effects of this dynamic vibration absorber are experimentally verified.This is used to provide a new reference for the design of dynamic vibration absorber.