Vibrations in High Speed Take-Up Winders

Abstract

Recent progress in spinning technology toward high speed spinning requires take-up winders of very high winding speed and it becomes more important to understand the vibrational behaviors of the winders. Basically, take-up wind ers are composed of two components, (a) package and package spindle assembly and (b) friction drum and pressing mechanism. Vibrations of these two components are coupled each other through dynamic compressive characteristics of cylindrical yarn packages. To study the coupled vibrations of take-up winders, are proposed equivalent dynamic models expressed by lumped parameter systems. Introducing experimental results of the dynamic compressive char acteristics of packages into these models, the coupled vibrations of the winders can be analyzed mathematically.The following are the results of theoretical and experimental analysis of actual winders for mill use : (1) Two equivalent dynamic models of the take-up winders are proposed, which represent their basic vibrational behaviors fairly well.(2) One of the natural frequencies of the coupled system is always nearly equal to the natural frequency of the package and spindle assembly.(3) Due to coupling through dynamic compressive characteristics of packages, there exists another natural fre quency higher than that of the package and spindle assembly alone. This frequency is remarkably affected by the dynamic characteristics of the packages.(4) The above-mentioned two natural frequencies rapidly decrease as the packages grow up. Other natural fre quencies remain nearly constant during the package growth.(5) It should be noticed that many of the natural frequencies of the coupled system are quite different from those of the uncoupled system.