立方体状の粘弾性体と質量を組み合わせた多方向動吸振器の開発

抄録

Flexural vibration modes of railway vehicle car bodies around 10 Hz negatively affect ride comfort because humans are sensitive to this frequency range. The purpose of this study is to develop a new vibration reduction device which can reduce some flexural vibration modes. In this paper, we developed a cube filled dynamic vibration absorber (called CFDVA in this report), which consists of iron blocks, viscoelastic blocks, and a container. The multidirectional motion of iron blocks are expected to reduce three-dimensional flexural vibration modes. The CFDVA has a mechanism to adjust the frequency by changing the arrangement of viscoelastic blocks and iron blocks and apply to various types of car bodies which have different natural frequencies. We conducted a vibration test on CFDVA alone to investigate the natural frequencies. As a result, CFDVA has a mechanism that can adjust the natural frequency in each of the vertical and horizontal direction, and we were able to determine the appropriate placement for the scale model. And then, a FEM model of the CFDVA is constructed to verify the mechanism of the vibration reduction, and it was confirmed that the same tendency as in the vibration test, but there was a quantitative difference.