US2896435A - Yarn tensioning device for circular knitting machine - Google Patents

Description

y 1959 c. P. BERG 2,896,435

YARN TENSIONING DEVICE FOR CIRCULAR KNITTING MACHINE Filed Aug 6. 1956 136115 ATTORJVEY United States Patent Chester P. Berg, Birdsboro, Pa., assignor to Manor Hosiery Mills, Inc., Birdsboro, Pa.

Application August 6, 1956, Serial No 602,378

1 Claim. 01. 66-146) This invention relates to circular knit hosiery and, more particularly, to a circular knitting machine, a yarn tensioning attachment and to a method of knitting seamless hosiery, particularly the welt portion thereof.

The conventional method of knitting ladies seamless hosiery in circular knitting machines is to use preshrunk yarn, such as preshrunk nylon yarn, for knitting the welt portion, as well as other portions, so that high temperatures encountered in subsequent operations, such as the dyeing and preboarding operations, will not cause further shrinkage of the yarn. While the use of preshrunk nylon yarn avoids the disadvantages of later shrinking of the yarn and of the welt, which would cause discomfort to the wearer, it has the outstanding disadvantage of requiring expensive yarn material since preshrunk nylon yarn is rather costly. Furthermore, the use of preshrunk nylon yarn does not permit sufiicient stretchability in the welt portion, therefore is disadvantageous since substantial flexibility is a desideratum in the welt to give wearing comfort and eliminate formation of welt impressions on the wearers legs. Furthermore, preshrunk nylon yarns still cause certain defects in the welt such as distorted stitches sometimes referred to as crows feet or hen tracks" resulting in unattractive and imperfect hosiery.

An object of this invention is to provide a novel method and apparatus for circular knitting of hosiery of the seamless type, particularly the welt or shadow-welt portions thereof, which will overcome the above stated disadvantages.

A further object of this invention is to provide a novel method of knitting and a novel tension controlling attachment for a circular knitting machine, which will enable the use of very inexpensive yarn in its raw state, that is without preshrinking, and thus consider-ably reduce the cost of makingladies hosiery, and simultaneously improve the quality of the hosiery.

A more specific object of this invention is to provide a novel tension controlling attachment for a circular knitting machine which will enable loose knitting with raw yarn for making the welt portion of ladies seamless hosiery, thereby providing a considerable increase in stretchability of the welt, as compared to knitting with preshrunk nylon yarn under tension, and giving an amazingly high degr of comfort to the wearer.

A more specific object of this invention is to provide in a tension control device for any seamless knitting machine a tension control means responsive to operations of the yarn feeding finger so as to effect loosening of the tension when raw yarn is being knitted to form the welt portion, or shadow-welt portion, and so as to elfect tighten ing of the tension when it is not being knitted.

Other objects and advantages of the invention will become more apparent from a study of the following specification taken with the accompanying drawing, wherein the single figure is a vertical elevational view of the yarn feeding and tensioning portion of a circular knitting machine and including a tension controlling attachment embodying the principles of the present invention.

Referring more particularly to the drawing, numeral 1 denotes a cone or bobbin supplying yarn 2 which is fed into a seamless knitting machine of any type. In accordance with the present invention, yarn 2, instead of being preshrunk, such as is the conventionally used preshrunk-S-turn nylons, is merely raw yarn, such as raw nylon yarn, as it comes from the producer of nylon yarn, therefore, which yarn is very inexpensive in cost and whose fibers are rather loosely held together. Yam 2 may be raw nylon from pern /2 turn only and is fed through an eye 3 loosely supported on a U-shaped bracket 4, which bracket is suspended from a branch 5 extending from a stand or post 6. A plurality of branches (not shown) similar to branch 5 extend from post 6, each of which supports a similar U-shaped bracket and eye for guiding yarn coming from other cones (not shown). Also supported on the stand 6 is a yarn take-up bracket 7, partially shown, which is conventionally used in the Scott and Williams KN type circular knitting machine, and denoted as S.W. 24,259 AX.

In accordance with the present invention, any suitable fastening means is used for attaching the tension controlling device 10 to a stationary part of the machine, such as the take-up bracket 7. For example, a cylindrical or barrel shaped element 9 may serve as the fastening means and has a screw threaded into its top portion for fastening the leaf element 8 of bracket 7 to its top portion and has a similar screw in its bottom portion for fastening tension controlling device 10 to bracket 7 by means of element 9.

The tension controlling device 10, itself, is well known in the art and forms a component part of the Scott and Williams machine. It comprises a solid bracket with downwardly extending end flanges 10a on which is pivotally mounted a rocker assembly including a plurality of arms 11, 12 and 13 which are pivotally mounted in unison underneath the bracket. The arms 11, 12 and 13 are slotted at one end. Mounted in the slots are eyes 11a, 12a, and 13a, respectively, which are in registry and through which the yarn 2 passes. Rigidly secured to the side of the bracket of tension controlling device 10 are a pair of spools 14 and 15 of ceramic or other suitable material for guiding the yarn and for applying tension thereto in a manner to be described hereinafter. At one end of the bracket of 10 is screw threaded a post 16 for adjustably supporting one end of a coil spring 17, the other end of which spring is connected to the other extremity of arm 11, whereby spring 17 serves as a return spring for biasing the arms 11, 12 and 13 clockwise to a position shown in dash outline such that eyes 11a, 12a and 13a will align below the central portions of spools 14 and 15, thus yarn will not contact the spools, thereby removing tension from the yarn.

In accordance with the present invention, a coil spring 18 is connected, at one end, to one extremity of arm 11, and at the other end, to the end of a yarn feed finger 19 and, more specifically, to the yarn feed finger which controls the knitting of the welt or shadow-Welt portion of the hosiery. Spring 18 is connected to the appropriate yarn feed finger 19 by means of wire 23.

Each of the yarn feed fingers 19 has a spring 20 connected to one extremity of the finger, the other end of the spring 20 being connected to the top flanged portion of plate 21. Springs 20 act as return springs for biasing fingers 19 in a clockwise direction about pivot 22 as a center. After yarn 2 has passed through the tension control device 10, it passes through an eye 26, thence through a groove formed in the end portion of finger 19 and finally is led to a conventional assembly on dial cap 24 which includes a yarn binder and a scissors-like cutter (not shown) for holding the thread and for cutting it in a manner well known in the art. Such assembly, per se,

forms no part of the present invention since it is a well known component part of a circular knitting machine, such as a Scott and Williams KN type.

In operation, yarn 2 is normally fed through the tension control device when the arms 11, 12, and 13 are in theposition shown in full lines, that is, when the eyes 11a,-12a and 13a are in the paths of spools 14 and 15, so thatthe thread will assume a sinuous path and engage the lower surfaces of spools 14 and 15 whereby the spools will effect tensioning of the yarn. However, let us assume that the welt-controlling finger 19 is moved to the dash line position in order to effect knitting of the welt (or shadow-welt) portion of the hosiery. Immediately. before this takes place it will be noted that tension spring 18 is stronger than return spring 17, therefore, will bias the rocker assembly, that is, arms 11, 12 and 13, to the position shown in full lines, that is, in the yarn tensioning position. But as soon as the appropriate finger 19 which controls the knitting of the welt (such as the No. 2 finger) is moved to the dash line position to effect such knitting it will lift the lower end extremity of wire 23 and thus relieve the tension on spring 18 and enable return spring 17 to rotate the rocker arms 11, 12 and 13 clockwise to the position shown in dash lines, that is, to the non-tensioning position, whereby the yarn is passed solely through eyes 11a, 12a, and 13a, without contacting the surfaces of spools 14 and 15, and thus knit the yarn is under no tension, that is, it is in loose condition while it is being knitted to form the welt. As soon as the knitting of the welt has been completed, the finger 19 which was in the position shown in dash outline, will now be moved in a well known manner to the full line position, therefore again tensioning spring 18 so as to overcome the action of weaker spring 17 and restore the parts to the position shown in full lines in the drawing, that is, to the yarn tensioning position. Thus, the raw yarn for knitting any particular portion of the stocking, such as a welt or shadow-welt portion, or in fact, any other portion, may be effectively controlled by the pivotal movements of the particular figure 19 which controls the knitting of the particular portion of the stocking. The yarn feed fingers needles, and associated parts, which are well known in the circular knitting machine art, are shown in greater detail in Pons Patent 2,472,614, Lawson et al. Patent 1,757,434 and Pratt Patent 1,825,089.

In the practice of my invention, that is, in applying it to the Scott and Williams circular knitting machine type KN, the catalog spring number 10,282 is removed and a new spring, denoted as 18 on the drawing, is substituted which spring is preferably about 3 inches long with a coil diameter of .187 x .015 inch wire diameter.

Flexible piano wire, denoted in the drawing by numeral 23, may be used having a thickness of .023 inch and which is linked to spring finger 19 on the welt controlling spring finger (catalog No. 205,523).

By knitting the welt portion, or shadow welt portion, with raw nylon yarn or other raw yarn, without tensioning, there will be produced a very stretchable welt portion having at least about 2 inches or more additional stretch than in preshrunk nylon welts. More specifically, the stretch is extended from perhaps 11 /2 inches to as much as 14 or 14 /2 inches. cessity of preboarding and prevents crows feet, and similar knitting imperfections. considerably increased stretchability of the welt of the finished hosiery results in an amazingly greater comfort in wear. And by using raw yarn of any linear polyarnide, such as nylon, or of other synthetic material, the cost of throwing is eliminated, as

It also eliminates the ne-,

well as the cost for preshrinking and twisting of the welt yarn. In short, the cost of making the stocking or other knit fabric is considerably reduced, whereas the quality is considerably increased, particularly as to stretchability of the welt as elimination of imperfect knitting, such as crows feet and the like.

While the loose, raw yarn has been described above for the making of the welt or shadow-welt portion, it should be noted that such yarn may also be knitted to form other portions of a stocking, and, in fact, if desired, the entire stocking, or perhaps other fabrics wherein stretchability is desired, as well as low cost in manufacture, for example ladies undergarments, such as girdles, brassieres, and the like.

Thus it will be seen that I have provided a novel circularly knit stocking and a novel tension controlling device in the form of an attachment that can be incorporated in the tension control device of a circular knitting machine, or other seamless knitting machine, wherein the tension of the yarn is controlled directly by the pivotal movements of the yarn feed finger, whereby the yarn may be fed loosely or without tension in the knitting of the welt or shadow welt-portion or other desired portion or portions of the stocking; also I have provided a very inexpensive attachment to enable knitting of ladies hosiery and other fabrics, wherein stretchability is desired, by the use of very inexpensive raw yarn, such as raw nylon yarn, therefore considerably reducing the cost of manufacture of such stockings and greatly increasing the stretchability, wearing comfort and perfection of the knit.

While I have illustrated and described a single specific embodiment of my invention, it will be understood that this is by way of illustration only, and that various changes and modifications may be made within the contemplation of my invention and within the scope of the following claim.

I claim:

In a circular knitting machine including a cone of raw yarn, and a yarn tensioning device comprising stationary aligned spools and a plurality of rocker arms having registering eyes mounted adjacent the ends thereof which are adapted to selectively move into and out of alignment with said spools to effect tensioning or relieve it, respectively, a return spring connected to said rocker arms and biasing them to the tension relieving position, a plurality of yarn feed fingers cooperable with the needles of said machine, spring means connecting one of said feed fingers, which controls knitting of the welt of a stocking, with said rocker arms against the action of said rocker arm return spring, whereby movement of said feed finger to the welt knitting position will relieve tension of said spring means and allow said return spring to move the rocker arms to the non tensioning position so as to knit said welt with loose raw yarn to produce a welt having substantial stretchability.

References Cited in the file of this patent UNITED STATES PATENTS 1,666,056 Epps Apr. 10, 1928 2,290,005 Toone July 14, 1942 2,332,738 Meade Oct. 26, 1943 2,396,166 Faucette Mar. 5, 1946 2,500,337 Berg Mar. 14, 1950 2,729,083 Rabinovitz Jan. 3, 1956 2,729,957 Pope Jan. 10, 1956 2,767,567 Jenard et al Oct. 23, 1956

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