Process and apparatus for making alternate s/z twist plied braid or joined alternate s/z twist plied yarns

Abstract

The present invention provides an improved method and device for producing an alternate S/Z twist plied braid and joined alternate S/Z twist plied yarns. The invention further provides an alternate S/Z twist plied braid and joined alternate S/Z twist plied yarns produced according to a process of the invention.

Description

TECHNICAL FIELD[0001]This invention relates to an improved method and apparatus for producing an alternate twist plied braid and joined alternate twist plied yarns. The invention further relates to alternate S / Z twist plied braid and joined alternate S / Z twist plied yarns obtained with the method.BACKGROUND[0002]The concept of producing alternate twist plied yarns using the alternate twist, self-twist phenomenon is now rather well known in the art. Documents in which the general principles of alternate twisting and self-twisting are described include the following: “Self-Twist Yarn”, D. E. Henshaw, Merrow Publishing C° , Ltd., Watford, Herts, England, 1971; RE 27,717 Breen et al; U.S. Pat. No. 3,225,533 Henshaw; U.S. Pat. No. 3,306,023 Henshaw et al.; U.S. Pat. No. 3,353,344 Clendening, Jr.; U.S. Pat. No. 3,434,275 Backer et al.; U.S. Pat. No. 3,443,370 Walls; U.S. Pat. No. 3,507,108 Yoshimura et al.; U.S. Pat. No. 3,717,988 Walls; U.S. Pat. No. 3,775,955 Shahand and U.S. Pat. No. 3...

AI Technical Summary

Benefits of technology

[0051]In a preferred embodiment, the fibers or filaments of the alternate S / Z twist plied yarns are heated using a hot fluidum when connecting their nodes. In a preferred embodiment, inter-fiber or -filament friction of the alternate S / Z twist plied yarns is reduced by the addition of liquid additives prior to or during imparting additional alternate twist of said yarns.

[0052]In a preferred embodiment, inter-fiber or -filament friction of the alternate S / Z twist plied yarns is reduced by the addition of liquid additives during the connection of their nodes.

Problems solved by technology

A tufted carpet made from yarn of this description exhibits two significant disadvantages, one of these being the fact that relatively minor variations in the manufacturing process, such as small variations in twist between spindles, causes large changes in the light reflectance characteristics of the carpet tufts, and the carpet can have a highly noticeable streaky appearance which is unacceptable.

The second major problem is that with S=1.4 P or more , the individual yarn strands tend to retain their identity as individual strands, even though plied, and tend to split at the tuft tips into separate singles strands which are visible and which give the carpet surface an undesirable “stringy” appearance.

In forming a braid from previously plied strands, the various forces interact in each plying process in such a way that it is difficult to predict the degree of twist which will exist after all of the steps, and it is therefore a rather complicated process to arrive at an end product which has twist relationships which meet desired specifications.

Such joining is very difficult in a production environment, because the yarn tensions are high after the imparting of additional twist, and because the filaments have low entanglement capabilities due to the prior joining of the nodes in the yarns.

The reliable and reproducible joining of the nodes of the alternate S / Z twist plied yarn has in practice proven impossible.

This is disadvantageous as it may cause discomfort, itching and scratching.

This is disadvantageous for the production speed and apparatus capacity.

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