US2493830A - Hosiery - Google Patents

Description

Jan. 10, 1950 J, PlCARD 2,493,830

HOSIERY Filed Oct. 30, 1946 IN ENTOR' @waMZL fi ATTORNEYS Patented Jan. 10, 1950 UNITED STATES PATENT OFFICE Application October 30, 1946, Serial No. 706,648

I '3 Claims. 1

This invention relates to hosiery, and has for its object the provision of certain improvements in hosiery manufacture.

Hose are customarily knit on one of two types of machines, fiat or circular. when knit flat, the hose is known as full-fashioned or fully shaped. The hose comes off this machine flat, and is folded together and seamed down the back to form a tube. The toe and heel are then attached,,leaving a small opening at the end of the toe or at the end of the heel, or at both ends, which is closed by a chain stitch in an operation known in the industry as looping.

Much the greater volume of hose is commercially fabricated on circular knitting machines. This machine customarily produces the entire hose, but leaves an opening between the toe and body portions. The opening is usually on top and extends over about half the circumference at the point where the toe joins the body portion. Approximate each edge of the opening, a loose course or open stitch is put in and knittin continued a short distance, say about onequarter inch or more, beyond the loose course to leave a marginal portion for looping. An operator (looper) then manually folds together the two mating halves of the marginal portion be- .yond the loose course so that the open stitches of the two halves of the loose course are aligned.

This is a painstaking and tedious operation, and

one of the major problems of the hosiery mill is to secure enough loopers for the mill's machine capacity. With the marginal portion so folded, the operatorplaces the hose on a looping machine in which a chain stitch through the mating loose course closes the opening andsimultaneously clips oil the excess marginal portions. With trained operators the looping operation takes about 45 seconds for each hose.

The present invention is especially adapted to close the toe opening left after fabrication of a hose on a circular knitting machine, but is equally applicable for closing any opening in a machine-fabricated hose, such for example as the aforementioned toe and heel openings in full-fashioned hose. In accordance with the invention, a thermoplastic bonding agent is associated with the juxtaposed and mating edges of the opening, and while so associated the agent is subjected to high frequency dielectric heating until it softens sufllciently to impregnate the terized by having the initial opening closed by the thermoplastic bonding'agent.

The foregoing and other novel features ofth invention will be best understood from the following description taken in'conjunction'with the accompanying drawing, in which Fig. 1 is an elevation of a hose-supporting mandrel suitable for the practice of the invention,

Fig. 2 is a detail elevation of the mandrel with a hose supported thereon,

Fig. 3 is an elevation of the mandrel and associated elements during the stage of high frequency dielectric heating,

Fig. 4 is a top plan of the equipment shown in Fig. 3,

Fig. 5 is a sectional elevation of a detail of the equipment shown in Fig. 3, and

Figs. 6 and 7 are plan and elevation, respectively, of a modified form of the movable electrode.

The hose supporting mandrel comprises a cylindrical body portion ll topped by a hemi-spherical dome l I. An electrode H, such as a flat metal ring, is provided at the junction of the body portion Ill and dome II. The electrode may be about A inch wide and inlayed so that its outer .face is flush with the outer adjacent surfaces of the body portion and dome. The electrode is electrically connected to one terminal of a source of high frequency electric energy (20 in Fig. 3) such as high frequency oscillator.

A hose I3, having the open toe characteristic of circular knitting. is pulled over the dome II with the greater length of the hose, especially in the case of womens hose, caught and held in a shelf or trough l4 surrounding the lower part of the body portion I0. The hose is knitted with no looselor open stitch and no marginal portion, but on the contrary knitting is terminated so that the toe and adjacent body portions of the hose have their desired completed shape when the mating edges of the opening are juxtaposed. In pulling the hose over the dome l I and adjusting it for subsequent treatment, the mating edges of the opening are carefully juxtaposed as indicated by the line I! in Figs. 2 and 5 showing those edges in exact abutting, juxtaposed position. The juxtaposed mating edges (I!) of the toe opening overlay the electrode II.

A band'li of thermoplastic material is next placed over the juxtaposed mating edges of the toe opening. The band completely surrounds the hose on the mandrel and, of course, overlaps the juxtaposed mating edges of the toe opening. A movable electrode is then placed around the thermoplastic band l6. In Figs. 3 and 4, this electrode includes two semi-circular parts I! connected by a hinge I8. The eflective electrode surface is a metallic ring closely surrounding the band It when the two parts of the electrode are closed and locked together. In Figs. 6 and '7 the movable electrode is a metal ring l9, slightly tapered on the inside surface if desired, which can he slipped over the thermoplastic band It. The movable electrode is elec- Where the a ing temperature is around 150 F.. and the band j is approximately 0.03 cm. thick, 0.70 cm. wide and 19 cm. in circumference, a-h'eating period of 10 to 12 seconds for one kilowatt of output is required. With nylon (whose melting temperature is about 480 F.) asthe thermoplastic material, the required" heating period for ,one kilowatt of output is about 28 seconds. With an oscillator of 2.5 kilowatt output, such as isnow readily available, the dielectric heating contemplated by the invention can be carried out in from 5 to seconds, although heating -periods;up to 30 seconds are not too long ecenomically} In the course of the high frequency dielectri heating, the thermoplastic material "softens or melts and impregnates the portions of the hose adjacent the juxtaposed mating edges of the toe opening. Upon cooling, the plastic material forms a strong bond between the toe and body portions of the hose. Thus, tli'e initial toe opening is closed by the thermoplastic bonding agent. The thermoplastic binder, in the form of v the invention hereinbefore described, extends all around the hose at the junction of the toe and body portions, althoughJt is only required, for bonding purposes, at the initial toe opening. Where it is undesired to have any thermoplastic binder on portions of the hose other than for closing the initial toe opening, a flat strip of thermoplastic material may be used in lieu of a band, and may be temporarily held over the juxtap'osed mating edges of the toe opening bya film of adhesive or the like. It is also possible to use the thermoplastic material in other forms, such as a tacky powder or paste which can be applied by brushing. spraying or the like to the vicinity of the juxtaposed mating edges of the toe opening on the mandrel. Y

The invention is particularly applicable to nylon hose since the thermoplastic material may then be a band or strip of nylon, and in subsequent dyeing the thermoplastic binder will take the dyes in substantially the same manner as the knitted nylon thread. Where the thermoplastic binder is not the same as the material of the knitted hose, it may, after dyeing, be of a somewhat different shade than the knitted hose, but its relatively small area and its location at the toe of the hose generally makes any such difference in shade of no practical significance.

A wide variety of thermoplastic materials are suitable for the practice of the invention. The thermoplastic binder should be resilient and elastic and of sumcient strength to serve as an effective bonding agent. Its softening or melting'temperature should be not less than about 150 F. and preferably somewhat higher in order to permit laundering of the hose in relatively hot water. On the other hand, for economic reasons. the softening or melting temperature of the thermoplastic material should not be too high, and I prefer materials with softening or melting temperatures under 500? I". I In addition to Vinylite 4- and nylon, other vinyl chloride and vinyl acetate polymers or co-polymers, styrene resins, urea-- formaldehyde resins, phenolic resins and various other thermoplastic synthetic resins are obtainable with characteristics suitable for the purposes of the invention. a

. The invention is applicable to all types ofmachine-fabricated hose made, for example, of silk,

nylon, cotton, rayon (including the regenerated cellulose, cellulose ester and similar varieties),'

wool etc. .With cotton and rayon hose, the thermoplastic binder "may advantageously be of a cellulosic base.

A- suitable source of high or radio frequency electric energy is theMegatherm high frequency generator. While I have hereinbefore mentioned a high frequency of 200 megacycles, this is not necessary since the contemplated dielectric heating can be attained with any radio frequency power developed by an oscillator or by any other suitable means. I

I claim:

1. 'The improvement in closing the open toe of a machine-fabricated hose which comprises placing the mating edges of the opening between the toe and the body portion of the hose in juxtaposed, flat-seaming' position over a mandrel having one electrode of a high frequency dielectric heating apparatus, with the juxtaposed edges'overlying said electrode, associating a thermoplastic bonding agent with the jux aposed mating edges, placing a second electrode of the high frequency dielectric heating apparatus over the juxtaposed mating edges and the associated thermoplastic bonding agent, and causing a high frequency current to pass between said electrodes until the thermoplastic material softens and unites with the juxtaposed edges-whereby on cooling of the softened thermoplastic material the juxtaposed edges will be bonded together.

2. The improvement in closing the open toe of machine-fabricated hose which comprises placing the mating edges of the opening between the toe and the body portions of the hose substantially .in abutting, juxtaposed position over a mandrel having one electrode of a high frequency dielectric heating apparatus, with the juxtaposed edges overlying said electrode, associating a thermoplastic bonding agent with the juxtaposed mating edges, placing a second electrode of the high frequency dielectric heating apparatus over the juxtaposed mating edges and the associated thermoplastic bonding agent, and causing a high overlying said electrode, associating a thermoplastic bonding agent with the juxtaposed mating 'edges, placing a second electrode of the high frepregnates' the juxtaposed edges. whereby on cool- Magoo ing of the softened thermoplastic material the I'OREIGN PATENTS.

juxtaposed edges will'be bonded together. Number comm. mm

W m 555,054 Great Britain "Aug. 3, 1943 I REFERENCES CITED 5 OTHER REFERENCES The following references are of record in the Electronlcs, Aug. 1943. Article by Hoyler 0 file of this patent: "An Electronic Sewing Machine." I

UNITED STATES PATENTS Number Name Date 2,157,116 Carothers 'May 9, 1939 2,224,036 Voorhls Dec. 3, 1940

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