Winding of conical packages at constant delivery rate - Part II: A new tension compensatory system for use in fixed rate delivery

WOS: 000075122500006The quality of a conical yarn package depends on the winding tension of the yarn wound onto the package. The problems of tension variation control during cone winding are different from those in cheese winding. In cone winding the peripheral speed of the package is varying and this results in the yarn tension changing during package building. This effect can be eliminated by storing and releasing a quantity of yam by means of a compensatory system. An analysis of the problem and the result of reducing variations in winding tensions are described

Deformation of a single helix under simultaneous application of extension, compression, and bending

WOS: 000087272400007An idealized model for a twisted yam structure assumes that each fiber or filament follows a helical path and the yam has a circular cross section in the undeformed state. An investigation of the behavior of a single helix can therefore be considered as a first step toward the mechanical analysis of yam deformation under simultaneous extension, compression, and bending, which is the kind of deformation that occurs in many textile processes and applications. This paper presents a theoretical model of the large-scale deformation of a single helix subjected to bending, compression, and extension. The work studies the effects of varying the ratio of the flexural rigidity to the torsional rigidity of the helix material and of varying the helix angle together with the variation of the deformation forces. The cross section of a deformed helix is discussed in relation to the position of the neutral axis and strain energy. Also, some experimental data are presented to show the relevance of the theoretical results to the experimental findings