Claims
- 1. A process for transferring a package of yarn from a hollow core to a dye spring, comprising:
- a. in any order:
- 1. inserting through a first end of said dye spring a reciprocally mounted first transfer head provided with an expandable portion adapted for expansion to grip the remote end of said dye spring,
- 2. positioning said remote end in axial alignment with said core and in close end-to-end relationship with one end of said core,
- 3. axially compressing said package, and
- 4. gripping said core with a second transfer head,
- followed by
- b. simultaneously withdrawing said core while inserting said remote end of said dye spring through said package.
- 2. The process of claim 1 wherein axial compression of the package of yarn is accomplished by pushing the package of yarn in the direction of the location of the second transfer head against a stationary plate member.
- 3. The process of claim 1 wherein the yarn is false twist textured yarn.
- 4. The process of claim 1 wherein the yarn is made of polyester polymer.
BACKGROUND OF THE INVENTION
This is a continuation of application Ser. No. 595,971 filed July 14, 1975, now abandoned.
1. Field of the Invention
The present invention relates to a process of substituting in situ one core for another core in a yarn package. More particularly, it relates to a process of substituting for a liquid-impermeable rigid core in a yarn package a liquid-permeable resilient core in preparation for dyeing or otherwise treating the yarn forming the package with a liquid.
2. Prior Art
Today vast quantities of man-made continuous filament yarn are textured by various processes in order to enhance the bulk and stretch characteristics of fabric made therefrom. One such texturing method involves heat setting a false twist imposed on a running threadline. After the false twist crimp is lastingly impressed on the threadline, it is taken up in an orderly manner by being wound on a core. It is commonplace that the core is fabricated from spirally wound paper or paperboard sheets using an adhesive to bond the paper plies. Such a core is rigid and normally imperforate to liquids and must be sufficiently strong to withstand contractive forces developed by the wound yarn. It is often desirable to dye in package form the textured yarn that has been wound on such a core. Package dyeing requires circulating dye liquid evenly through the package from outside to inside of the package or vice-versa. Obviously, an imperforate core does not permit even and thorough penetration of the dye liquid throughout the package as is needed. Hence, the yarn to be dyed must be removed or rewound on a core that permits passage therethrough of a dye liquid. Mere removal of the imperforate core is not satisfactory because the yarn on the inside windings of the package tends to become disarranged and entangled during dyeing. This gives rise to difficulties during subsequent knitting or weaving of the dyed yarn. Rewinding of the yarn from the imperforate core to a dye liquid-perforate core is quite expensive. At the present time it is common practice in the industry to replace the imperforate core with a perforate core without rewinding, thereby permitting free flow of liquid therethrough but at the same time having a core to impart needed stability to the windings during liquid treatment.
In U.S. Pat. No. 3,425,110 core replacement is accomplished by simultaneously inserting a perforate core, such as a foraminous stainless steel dye tube or dye spring, while removing the imperforate core by pushing out the former with the latter. The diameter of the replacement core is usually only very slightly smaller than the diameter of the imperforate core of the yarn package. It has been found that while the windings are rendered stable during liquid treatment and the small difference in diameter permits a correct amount of inward expansion of the package to achieve a desired uniform bulk level throughout the package, the windings become disarranged by the movement of the cores during transfer. In particular, the windings in the vicinity of where the replacement core enters the package and the inner windings are noticeably rumpled.
In U.S. Pat. No. 3,681,007 another core replacement procedure is suggested. A perforate core is placed internally of a rigid imperforate core of which yarn is wound. While the package is under axial compression the imperforate core is removed while at the same time preventing axial movement between the yarn package and the perforate core. To withstand the contraction forces of the yarn, the imperforate core must have a rather thick wall. For example a core with a 4 inch diameter may have a wall thickness of one fourth inch or more. Hence the difference between the outside diameter of the replacement core and the inside diameter of the yarn package is even larger. Unfortunately, such a difference permits the inside windings to expand to the extent that the bulk level of the yarn from inside to outside of the package is not satisfactorily uniform.
Hence, there is a need in the art to provide a core transfer process wherein disarrangement of the windings is minimized while at the same time a satisfactorily even bulk level is maintained throughout the package.
There is provided a new and useful process for replacing a rigid imperforate hollow cylindrical core internally supporting a package of yarn with a liquid permeable hollow cylindrical core of the same or slightly smaller diameter. A foraminous dye tube or dye spring is axially aligned with the imperforate core in close end-to-end relation. The liquid permeable core may be inserted into the imperforate core for a short distance only. For example, the liquid permeable core will be inserted for a distance of no more than about 35 percent of the lengthwise distance of the imperforate core. The package is positioned between a pair of pressure plates or discs. The plates are moved relative to one another to cause the package to be axially compressed by a squeezing action of the plates. A transfer head equipped with expandable rubber rings is inserted axially of the core; at least one rubber ring is positioned within the confines of each of the cores. Thereupon, the rubber rings are expanded to grip both of the cores. The transfer head is withdrawn from the centers of the cores as the package remains relatively stationary to simultaneously pull both cores in tandem along the axis of the yarn package for a predetermined distance during which time the rubber ring gripping the perforate core is decompressed to release the perforate core in a suitably centered position within the package. The transfer head is further withdrawn until the imperforate core is moved away from the package. Later the expanded rubber ring gripping the imperforate core is decompressed to release the imperforate core. The pressure plates are moved apart; and the package of yarn now containing a perforate core is removed for subsequent treatment, such as dyeing.
In a second embodiment of the present process, two transfer heads with expandable rubber rings are used. A first transfer head enters the imperforate core whereas the second transfer head enters the liquid permeable core. The package of yarn is placed under axial compression. The first head whose rubber ring or rings are expanded pulls the imperforate core out and away from the package while the other head whose rubber ring or rings are expanded pushes the liquid permeable core into the package to take the place of the imperforate core. The rubber ring or rings gripping the liquid permeable core are decompressed to release the liquid permeable core in a suitably centered position within the package. Then, the second transfer head is retracted to its original position. The rubber ring or rings of the first transfer head holding the imperforate core are decompressed to release the same. The axial pressure on the package is released; and the package of yarn containing the liquid permeable core is now readied for subsequent treatment, such as dyeing.
US Referenced Citations (13)
Continuations (1)
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Number |
Date |
Country |
| Parent |
595971 |
Jul 1975 |
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Patent Grant
4045858
