橡胶阻尼式动力吸振器固有频率测试方法分析

A Study on Methods for Measuring Natural Frequency of Rubber Damped Dynamic Vibration Absorber

考虑到橡胶元件的动刚度与激振振幅和激振频率有关,研究了不同激振形式下不同激励频率和激振幅值对橡胶阻尼式动力吸振器固有频率测试结果的影响.通常情况下,动力吸振器的固有频率的测试只考虑频率相关性,忽略了幅值相关性.文中分别采用恒振幅激振、恒加速度激振、随机加速度激振、脉冲激振和力锤敲击激振,对一橡胶阻尼式动力吸振器的固有频率进行了测试分析,给出了不同激振形式下动力吸振器的固有频率的测试值.结果表明:激振幅值对动力吸振器的固有频率的测试结果影响很大,目前一些企业采用的用力锤激振方法测试得到的橡胶阻尼式吸振器的固有频率并不能很好地表征动力吸振器的固有频率.文中结果为在真实振动工况下动力吸振器的固有频率的选择提供了依据.

Because the dynamic stiffness of a rubber component depends on the excitation amplitude and the excitation frequency,the influence of excitation methods and excitation values on the natural frequency of a rubber damped DVA is studied in this paper. In general,the natural frequency of the DVA is only considered frequencydependent,ignoring the amplitude correlation. The natural frequency of a rubber damped DVA is measured and compared under excitations of constant amplitude,constant acceleration, random acceleration, pulse excitation from a shaker and force hammer percussion,respectively. It is concluded that the measured natural frequency using force hammer excitation method does not well characterize the natural frequency of the dynamic vibration absorber in generic applications. The test method of the natural frequency of the dynamic vibration absorber described in this paper can provide the basis for the measuring natural frequency of a rubber damped DVA under the actual vibration condition.