Study on Pattern Formation Phenomena Gernerated in Contact Rotating Systems

1.将辊系视为多层结构，考虑辊轴的弯曲变形，将橡胶视为粘弹性体，将接触辊系视为具有粘弹性变形的时滞系统，分析了造纸机辊套橡胶的多边形变形现象。在此基础上，探讨了其形成机理，并提出了防止斑图形成的对策.其结果是，（1）辊覆盖橡胶的波纹化是由辊之间的异相模式引起的，（2）对于其中辊的弹性弯曲模式和刚性体过渡模式以相同相位叠加的异相模式中的凸模式，不能期望仅通过轴承支撑阻尼来有效抑制花纹形成，并且在旋转辊内的轴承之间安装非旋转中心轴防止了图案形成现象， 关于我们 中心轴与隔室之间的油膜起到阻尼作用，中心轴起到补充增强侧倾刚度的作用。因此，根据最佳条件，辊的操作旋转速度显著增加。对载重汽车和轿车轮胎的多边形磨损现象进行了实验和分析，明确了轮胎垂直方向第一阶固有振动模态引起多边形磨损的产生机理。在分析中，这种现象被建模为时滞系统伴随着自激磨损，其中轮胎的磨损量被反馈作为强制位移后的时间周期的旋转垂直方向。轮胎多边形磨损的增长过程是非常缓慢的，并且是通过在轮胎多边形数与旋转速度的乘积小于轮胎系统的固有频率的有限区域中产生的稳态磨损过程的不稳定振动来实现的。当产生多边形磨损时，轮胎以几乎正多边形的形状变形。轮胎磨损的表现形式和刚度几乎与发生区的宽度无关。另一方面，阻尼与产生区的宽度直接相关。实验结果与理论分析结果吻合较好，证实了轮胎多边形磨损的发生。少

1. Regarding the roll system as a multi-layred structure, taking flexural deformation of the roll axs into account, the rubber as a viscoelastic body and the contact roll system as a system with time lag accompanied by viscoelastic deformation, the polygonal deformation phenomena of roll-covering rubber in a paper making machine were analyzed. Then, their mechanisms were made clear and the countermeasures to prevent the pattern formation were discussed. As the results, (1) The polygonization of roll-covering rubber is caused by out-of-phase modes between rolls, (2) For the convex mode among out-of-phase modes in which the elastic bending mode and the rigid body transitional mode of the rolls are superimposed in the same phase, suppression of pattern formation by only bearing support damping can not be expected to be effective, and the installation of a non-rotating center shaft between bearings inside the rotating rolls prevents the pattern forming phenomenon because it is expected tha … More t the oil film between the center shaft and the cell contributes to the damping effect and the center shaft to the strengthening complementarily the roll stiffness. Hence, the operating rotational speed of the rolls is considerably increased in accordance with the optimum condition.2. The polygonal wear phenomenon of truck/bus and car tires was treated experimentally and analytically, and the generation mechanisms of the polygonal wear caused by the first natural vibration mode of the tire in the vertical direction were made clear. In the analysis, the phenomenon is modeled as time delay system accompanied by self-excited wear in which the wear amount of tire is fed back as forced displacement in the vertical direction after the time period of the rotation. The growth process of the polygonal wear of tire is very slow and is realized by the unstable vibration from steady-state wear process generated in the limited regions where the products of polygonal number and rotational speed of tire are less than the natural frequencies of the tire system. The tire is deformed in the shape of almost regular polygon when the polygonal wear is generated. The expression and the rigidity of tire wear are almost independent of the width of generation regions. On the other hand, the damping is directly related to the width of generation regions. A good agreement between experimental and analytical results concerning the occurrence of the polygonal wear of tire was confirmed. Less