US 3926381 A
Abstract available in
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Description (OCR text may contain errors)
States Patent Lawson et a1,
[ YARN TENSIONING MEANS 3,648,939 3/1972 ROSen 242/4701 3,702,176 11/1972 242/47.0l  lnvemors' John Provldence, 3,759,300 9/1973 Pfarrwaller 242/4701 Charles Cooper, Attleboro, Mass- 3,791,598 2/1974 Vischiani et a1. 242/4712  Assignee: Lawson-Hemphill, Inc., Central F ll R1 Primary Examiner-Stanley N. Gllreath Filed p 18 1974 Attorney, Agent, or FirmMiller, Frailey & Prestia  Appl. No.: 461,909 - ABSTRACT R l d [13 A li i D A yarn storage drum is provided with a separate exter-  Continuation-in-part of S61. NO. 431 478 Jan. 7 P for holding a plurality yam m 1974 1n selectlvely spaced, stacked relation. Each ring includes spacer means for supporting a next-above ring. 52 US. Cl. 242/4701; 242/4712; 242/128; 521811 g has an annular Set of elqngated fi s 242/147 R wh1ch pro ect from the base of the ring and incline 51 1111. (:1. B65H 51/20; B65H 59/00 toward the Storage drum and also Circumferentially 5 Field f Search 242 47 7 128, R thereto. The fingers of the lower rings overlap those of the upper rings, and the tips of the two fingers of each 5 References Cited ring contact the periphery of the drum and together UNITED STATES PATENTS apply a selected uniform tension to the yarn. The tension rings are free to float transversely with respect to 3,411,548 11/1968 Pfarrwaller 242/47.12 X the drum. 3,490,710 1/1970 Muhlhausler 242/4701 4 Claims, 6 Drawing Figures l8 Y\,: If r 12 1 Z 25 if US. Patent D56. 16, 1975 Sheet 1 of2 3,926,381
f 26 L Y :\\I if 2 US. Patent Dec. 16, 1975 Sheet 2 of2 3,926,381
YARN TENSIONING MEANS CROSS REFERENCE TO OTHER APPLICATIONS This application is a continuation-in-part of our pending patent application Ser. No. 431,478, filed Jan. 7, 1974, entitled Yarn Tensioning Device.
BACKGROUND OF THE INVENTION This invention concerns yarn storage devices of the type wherein a drum, which may either be rotational or fixed, takes up yarn from a yarn package for delivery to a yarn consuming machine. The yarn is wound tangentially on the drum, usually intermittently, and is pulled continuously therefrom axially through a tensioning ring which encircles the drum and which applies a drag or tension to the yarn.
The invention relates specifically to yarn storage devices of the type wherein the tensioning rings consist of a base ring from which extend a plurality of elongated fingers at regularly spaced intervals. The fingers project along lines which incline toward the axis of the storage drum and also extend circumferentially thereto. The distal ends of the fingers rest against the surface of the drum.
Tension rings for the purpose of applying tension or drag to yarn being pulled from a yarn package or other yarn storage means or device are well known in the art. See, for example, US. Patents to Chapman US. Pat. No. 350,345, Grothey US Pat. No. 2,366,101, Gift US. Pat. No. 2,838,922, Sarfati et al. US. Pat. No. 3,225,446, Rosen US. Pat. No. 3,648,939 and Rosen US. Pat. No. 3,702,176; and British Pat. Nos. 12,321 (1885) and 6727 (1892).
SUMMARY OF THE INVENTION A principal object of the present invention is to provide improved tension means for yarn storage devices of the type referred to hereinabove.
The object of the invention is achieved by providing a separate support exterior of the yarn storage drum for supporting at least one tension ring in an encircling position about the drum and at a spaced distance therefrom. This arrangement avoids the annular shoulder on the drum used by some of the prior art devices to support the tension ring on the drum, and thereby reduces the angle of contact of the yarn with the take-off yarn guide which is spaced from the drum on the projected axis thereof. Reducing this angle of contact provides a smoother yarn travel or flow to the yarn consuming machine.
The further object of the invention is to provide a plurality of tension rings, stacked one above the other, at such axially spaced separations that the fingers of each lower ring overlap those of the next above ring without any contact between the fingers of the upper and lower rings, whereby yarn pulled from the storage drum is selectively and controllably tensioned by the fingers of each of the axially stacked tension rings.
It is common practice with tension rings of similar design, such as shown in Rosen v US. Pat. No. 3,702,176, to stack multiple rings to achieve higher tensions without regard to the axial relation of the rings. However, such stacking leads to unpredictable and uncontrollable tensions. For, when tension rings are stacked so as to cause interference between the fingers of one ring and another, the flexing ability of the fingers of one ring is affected by the pressure of the fingers of the other ring, and the resulting tension on the yarn is not a simple addition of the effect of the two rings. It is, therefore, a further object of this invention to provide a tension ring design whereby rings may be stacked to achieve increased tensions wherein each additional ring adds only that increase in tension which it is designed to add, that is, each additional ring adds only that tension it alone would provide in the absence of other rings.
Further, it has been demonstrated that, when higher yarn tensions are required, a more uniform, smoother tension is achieved through the use of multiple light tension rings rather than from using a single stiffer or more rigid ring designed to produce the same total tension. This is because the stronger fingers of such a single ring tend to pluck the yarn and produce a bumpy yarn flow. The smaller the drag of each finger on a yarn the less the pluck effect. Thus, where two or three times as many fingers can be used to produce a selected tension, the smoother will be the yarn flow.
Additionally, it should be noted that an increase in bulk of a yarn, such as a knot or slub, will pass under multiple sets of light, easily-flexed fingers much more smoothly than it will pass under a single set of relatively stiff fingers.
In the preferred arrangement, the lowermost tension ring rests loosely on an external support ring, and each succeeding tension ring stacked above it rests loosely on the next lower ring. This arrangement permits each tension ring to float in the transverse plane of its base ring, with respect to the yarn storage drum. Thus, each tension ring is free to move radially, in the transverse plane of its base ring, until the opposing arcuate forces exerted by its fingers on the periphery of the storage drum are substantially in balance. By reason of this freedom to float radially, or transversely, with respect to the storage drum, the distal ends of the fingers of each tensioning ring exert a highly uniform tension or drag on the yarn, as it is withdrawn from the drum.
As a result of this capacity of the rings to float, and thereby seek an equilibrium condition of substantially uniform finger pressure circumferentially about the drum, compensation is provided automatically for slight but routine defects, such as molding errors in the fingers of the tension ring, axial misalignment of the parts, e.g. between the storage drum and the ring support, and run-out or wobble conditions occurring between the periphery of the storage drum and the tension ring support arising, for example, from defects in the drum or its supporting shaft.
BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevational view, partly in section, of the lower portion of a known form of yarn storage device having thereon two tensioning rings supported in accordance with the present invention;
FIG. 2 is a view looking along the line 22 of FIG. 1;
FIG. 3 is a plan view of one form of tensioning ring provided in accordance with the present invention;
FIG. 4 is a view in section along the line 44 of FIG.
FIG. 5 is a plan view of another form of tensioning ring in accordance with the present invention;
FIG. 6 is a view in section along the line 66 of FIG. 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 there is shown, largely in section, the lower portion of a known form of yarn storage feeder having a stationary drum which receives yarn tangentially from a yarn package (not shown) and about which the yarn Y is collected. A storage feeder of the type shown partially in FIG. 1 is shown in detail in John B. Lawson US. Pat. No. 3,776,480, issued Dec. 4, 1973, entitled Yam Handling Apparatus.
In some forms of storage devices, the yarn collecting drum 10 is rotatable. So far as the present invention is concerned, the drum may be either stationary or rotatable. However, in the particular form illustrated in FIG. 1, the yarn collecting drum 10 is stationary and the yarn Y is wound thereabove by a rotatable yarn guide (not shown) which is revolvable about the drum. For such a rotatable yarn guide, see the aforesaid US. Pat. No. 3,776,480.
As yarn Y on the storage drum 10 is pulled downwardly to the yam-consuming equipment (not shown) it leaves the peripheral surface of the yarn storage drum 10 and passes through a stationary yarn guide 16 supported by a channel bracket 17. Yarn guide 16 is located below the yarn collecting drum 10 on the projected center axis thereof. Stationary bracket 17 is supported at its upper end from the frame of the device.
In accordance with the present invention, stationary bracket 17 supports a ring 20 in such a position that it encircles drum 10 near the lower end thereof. Ring 20 may preferably be metal and may consist of a circular loop from which a pair of arms 21 extend radially outwardly. The ends of the radial arms 21 are supported in a pin 22 which extends across the channel of bracket 17 and is supported in the sidewalls thereof. The pin 22 may be provided with a locking detent fastened to bracket 17 or other means which allows the ring 20 to be adjusted into position by pivotal movement about pin 22 so that ring 20 may be swung down to load tension rings 25 onto it. The particular means just described for securing ring 20 pivotally to bracket 17 is not important to the present invention. Any suitable means may be used. It is important, however, that the ring 20 be supported by a bracket or other means spaced radially outwardly from the drum l0, and that such means be capable of supporting the loop or ring 20 in an encircling position about drum 10 at a small, spaced distance therefrom, as seen in FIG. 1.
In accordance with a preferred embodiment of the present invention, the ring 20 is used to support one or more yarn tension rings 25. The tension rings 25, preferably plastic, are provided integrally with spacer means so that they can be stacked one above the other at selected, axially spaced locations.
Each of the tension rings 25 may be identical to the other. In a preferred form, illustrated in FIGS. 3 and 4, each ring 25 has an annular base portion or ring 26 which is provided with an integral annular rib 28. Rib 28 performs two functions. One, it stiffens the annular base portion 26. Two, it functions as a spacer, as will be described.
From the inner rim of each ring 25 an annular set of elongated fingers 27 and 127 extend downwardly and inwardly. These fingers may preferably be at regular spaced locations leaving interstices between the fingers. The fingers are inclined inwardly toward the axis 4 0f the ring, as seen in FIG. 4. They also extend in the circumferential direction, as seen in FIG. 3.
The height of rib 28 is chosen to provide the desired axial spacing between the lower and upper rings 25 and their fingers 27 and 127, so that the fingers of the two rings are in overlapping relation, but not contacting, as seen in FIGS. 1-4, with the tips of the fingers of the two rings resting on the surface of the drum 10. While the two tension rings 25 will usually be identical, the component parts of the upper and lower rings are distinguished by reference numerals which differ by 100. For example, in FIG. 2, the fingers of the upper ring are 27; the fingers of the lower ring are 127.
While only two tension rings 25 are shown in FIGS. 1-4, the present invention contemplates that more than two may be used, and in FIGS. 5 and 6, three tension rings are illustrated. In addition, FIGS. 5 and 6 illustrate another form of tension ring, in which the spacer means, in lieu of the annular rib 28 shown in FIGS. 3 and 4, consists of a plurality of posts 29, three being shown at spacing. The number of posts 29 may, of course, be greater than three. The form of spacer shown in FIGS. 5 and 6 is not, however, presently preferred since the stiffening effect of the rib 28 is lost.
The lowermost tension ring 25 rests loosely on the support ring 20. This arrangement permits yarn tension ring 25 to float radially, in the transverse plane of its base ring or portion 26, with respect to the yarn storage drum 10. Thus, tension ring 25 is free to move radially in the transverse plane of its base ring, until the opposing arcuate forces exerted by its fingers on the surface of the storage drum 10 are substantially in balance.
Similarly, each of the succeeding, axially stacked yarn tension rings 25 is supported loosely on the annular rib 28 of the ring 25 next below it. Thus, each of the upper yarn tension rings 25 also is free to float in the transverse plane of its base ring 26, until it finds a position of equilibrium, in which its fingers exert a substantially uniform pressure circumferentially about the drum.
This capacity of the individual yarn tension rings 25 to float, until they adjust themselves to a position of exerting substantially equal finger pressure about the storage drum, serves to compensate automatically for minor defects of alignment or construction in the axially disposed parts of the yarn storage feeder. It also serves to enhance the uniformity of the tension exerted by the tension rings on the yarn.
The tension ring means shown and described in the present application has other advantages over prior art devices. Since no shoulder is required on the drum surface below the tension ring 25 to support the ring, the yarn slides down along the drum surface to the centrally located yarn guide 16 along a path which provides a reduced angle of contact with the guide, thereby providing a smoother yarn path. This is, of course, advantageous. This advantage is obtained whether or not two or more tension rings are used.
Further, since the yarn tension rings 25 are supported about the storage drum 10 by the separate, external support ring 20, the tendency of the yarn tension rings 25 to fall off the drum is, for all practical purposes, eliminated. One of the difficulties with the prior art devices, which utilize an annular shoulder on the storage drum to support the yarn tension rings, is the tendency for the rings to be knocked off of the drum when they are disturbed or jarred by knots or slubs or similar imperfections in the yarn passing under the tension ring as it is withdrawn from the drum.
Another advantage arises from the employment of two or more tenstion rings 25, stacked one above the other, in such relative positions that the fingers of one ring do not contact the fingers of another ring. As the yarn leaves the drum 10, a separate drag is applied thereto by each set of axially spaced fingers. Thus, additional drag may be added by adding additional tension rings. The two or more tenstion rings are free to move angularly, as well as radially, relative to the drum and also relative to each other. In operation, as the yarn is pulled past the tips of the fingers of the two or more sets of fingers, the rings will move or float relative to each other until the most uniform tension possible is applied to the yarn. Thus, the present invention, by using two or more sets of tension rings applies a more even tension, as compared with that provided by prior art devices.
What is claimed is:
l. A yarn tension ring for a yarn storing device having a yarn storage drum, said tension ring including:
a. a base ring for surrounding the storage drum,
b. a plurality of bristle-like flexible elements extending from the base ring axially beyond the base ring and inwardly toward the axis of the ring, whereby the tips of the flexible elements are contiguous with the surface of the drum when the tension ring is mounted relative thereto, and
c. means for locating a second yarn tensioning ring surrounding the storage drum at a selected, axially spaced, distance from said tension ring to space the tips of the flexible elements of of a second yarn tension ring from the tips of the flexible elements of said tension ring a distance sufficient to avoid contact between the respective flexible elements of said tension ring and a second ring,
(1. said locating means comprising spacer means mounted on the base ring and extending from the base ring in a direction generally opposed to the direction toward which the flexible elements extend from the base ring.
2. A tension ring according to claim 1, wherein the spacer means comprises an annular rib integral with the base ring of the tension ring.
3. A tension ring according to claim 1, wherein the spacer means comprises a plurality of spaced, generally annularly-arranged, protuberances formed integrally with the base ring of the tension ring.
4. Yarn tensioning means for a yarn storing device having a yarn storage drum, said tensioning means comprising a. a plurality of axially stacked yarn tension rings surrounding the drum,
b. each tension ring comprising a base ring and a plurality of bristle-like flexible elements extending from the base ring axially beyond the base ring and inwardly toward the axis of the ring, whereby the tips of the flexible elements are contiguous with the surface of the drum when the tension ring is mounted relative thereto, and
c. means for locating the plurality of tension rings at spaced intervals axially of the storage drum with the tips of the flexible elements of each ring spaced axially from the tips of the flexible elements of each next adjacent ring a distance sufficient to avoid contact between the respective flexible elements of said adjacent rings,
d. said locating means comprising i. a support ring disposed externally of the drum for supporting the stack of yarn tension rings, and ii. spacer means mounted on the base ring of each yarn tension ring and extending from the base ring in a direction generally opposed to the direction toward which the flexible elements extend