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The synthetic filament winder drives the filament through the traverse mechanism with rotary wings so that it can complete the transverse reciprocating motion when it is continuously wound and achieve the spiral distribution on the cylindrical package. When the existing traverse mechanism leads the filament, the filament is easy to oscillate and breaks away from the control of the rotary blade during the reversing process at both ends of the package, which directly affects its forming on the package. In this study, firstly, the filament leading process is analyzed from the filament leading principle of the traverse mechanism with rotary wings and the key points of the profile are identified. Secondly, we applied parameter constraints of key points and developed a blade profile that can not only meet the demand of filament reversing but also improve the above abnormal phenomena by curve-fitting, so that the blade can continuously and stably lead and control the filament during the reversing process. Finally, through the actual winding experiment, we contrasted the state of the filament leading process of the original blades with the improved blades, and verified the improvement effect. This study provides a design basis and optimization reference for realizing a smooth and stable relay between the filament and blades. [ABSTRACT FROM AUTHOR]

During the winding process, the filament moves at a high speed with multiple configurations and large deformations, and is acted upon by winding tension, contact force, transverse force, air resistance, and so on. Accurately predicting the trajectory and tension fluctuation of the filament under the high-speed running condition is the basis for regulating winding parameters and ensuring high-quality winding. This paper proposed a novel dynamic approach for modeling the polyester filament winding system. The filament element was established by absolute nodal coordinate formulation. The nonlinear spring and viscous damper elements were used to establish the contact model between the filament and the mechanical parts, and the mechanical model of the influence of the airflow on the filament was established. Through considering the moving filament and all the force factors, the dynamic model of the multi-body coupling system of the filament winding and the corresponding nonlinear dynamic equation were established, and the dynamic equations were solved using MATLAB. An example of the high-speed winding system was simulated and further analyzed, and the simulated trajectory of the moving filament was highly consistent with the experimental image record. [ABSTRACT FROM AUTHOR]

A filament bundle is a type of yarn, which is composed of nearly parallel and highly oriented polymer monofilaments. Due to its nonlinearity both in material constitutive properties and structure, the filament bundle possesses nonlinear viscoelastic properties. It is important to study the dynamic behavior of the filament bundle accurately during its high-speed movement. Therefore, an accurate expression of the constitutive relation of the filament bundle is an essential prerequisite for its dynamic simulation and analysis. Continued the previous study in Part I: modeling filament bundle method, in this paper, an approach was proposed to identify the equivalent dynamic constitutive parameters of the filament bundle considering frequency-dependent characteristics. Firstly, the identification formulas of the dynamic elastic modulus and viscoelastic coefficients were derived based on the Kelvin model. Then, a testing method of the cross-sectional parameters of the filament bundle under a certain tension was proposed, and the testing device was developed to obtain the area of the filament bundle; The dynamic loading test of the bundle filament was conducted in a DMA Q800 dynamic mechanical tester. Thirdly, the equivalent dynamic elastic modulus and viscoelastic coefficients were obtained through the experimental test. Finally, an analytical method was proposed to verify the correctness of experimental results through simulation. The results show that the excitation frequency has a significant influence on the dynamic elastic modulus and viscoelastic coefficient, and the curves of the equivalent dynamic elastic modulus and viscoelastic coefficient present nonlinear variation characteristics. [ABSTRACT FROM AUTHOR]

During the high-speed winding of polyester filament, a contact roller must be applied to press on the filament package's surface to ensure the filament is placed stably and precisely on the package surface. Thus, a twin-rotor system with contact coupling characteristics between the contact roller and the filament package is formed. Identifying the contact parameters between the contact roller and the package are prerequisite to precisely analyze the dynamic behavior of the winding system, as well as to determine the technical parameters. In this paper, an approach was proposed to identify the equivalent contact stiffness and contact damping coefficients by means of coordination through experiment and simulation. First, based on the forced non-resonance method of a single-degree-of-freedom system, the testing scheme was drawn up in consideration of the winding process parameters. Then, an experimental device for the twin-rotor system was developed, and the dynamic contact parameters just in the working frequency band corresponding to low linear speed of winding were obtained by the experiment, due to the requirement of the forced non-resonance theory and economic limitations of the experimental device. Third, the basic parameters including equivalent radial Young's modulus and damping ratio of the package were obtained through experimental test. Furthermore, the contact parameters in the working frequency band corresponding to high linear speed of winding were obtained through simulation. Finally, the curve fitting of contact parameters was finished; in addition, the comparative results between the simulation and the experiment are in good agreement. The dynamic contact parameters present nonlinear frequency variation characteristics. [ABSTRACT FROM AUTHOR]

A filament bundle is a kind of filament assembly with less twist or nontwist. It is a viscoelastic body and has a large aspect ratio. Its large deformation during motion over a wide range is a universal phenomenon in many textile processes. The dynamic viscoelasticity of the filament bundle, gravity, and air resistance are three important factors affecting the filament bundle's dynamic behavior. Taking account of these factors, a filament bundle dynamics analysis method is proposed in a series of three papers. This paper, the first in the series, presents an approach to model the dynamics of the flexible filament bundle with viscoelasticity and to analyze its dynamic behavior under the action of gravity and air resistance. The filament bundle element (FBE) is established based on absolute nodal coordinate formulation (ANCF), in which slope vectors and global coordinates are applied. The approach presented in this paper is well suited for the analysis of large deformation motions of filament bundles. As an example, a dynamic model was established to predict the filament bundle's trace during its swinging through large displacements under the action of gravity and air resistance, taking into account the filament bundle viscosity. The nonlinear differential equations of the filament bundle system were solved using MATLAB. Furthermore, the swing traces of the filament bundle in a closed Plexiglas box with different vacuum degrees were recorded using a high-speed camera to prove the validity of the established filament bundle model based on ANCF. [ABSTRACT FROM AUTHOR]