US3277537A - Yarn guide for shaping tow - Google Patents

Description

Oct. 11, 1966 R. M. ROEDER ETAL 3,277,537

YARN GUIDE FOR SHAPING TOW Filed March 2, 1964 5 Sheets-Sheet l FIG.J0 FIG. Eb

I NVENTORS RICHARD M. ROEDER DAVID DONALD DRUMMOND, JR.

ATTORNEY Oct. 11, 1966 R. M. ROEDER ETAL 3,277,537

YARN GUIDE FOR SHAPING TOW 3 Sheets-Sheet Filed March 2, 1964 RR m? NED ON WRO 1 MM U DR RD MD L A N 0 ATTORNEY Oct. 11, 1966 R. M. ROEDER ETAL 3,277,537

YARN GUIDE FOR SHAPING TOW Filed March 2, 1964 5 Sheets-Sheet :5

INVENTORS RICHARD M. ROEDER DAVID DONALD DRUMMOND, JR

BY 8M4 ATTORNEY United States Patent Wee Ware Filed Mar. 2, 1964, Ser. No. 348,529 1 Claim. (Cl. 19-161) This invention relates to the production of synthetic fibers. It is particularly concerned with that phase of fiber production involving the formation of tow and the improvement of tow quality.

Tows of synthetic fibers are formed by combining several ribbons of fibers, each ribbon being made up of continuous, discrete fibers obtained from a number of spinnerets. A tow usually has a denier in the hundreds of thousands. The tow is made up by carefully arranging the ribbons so that the tow will be even in thickness from side to side. In this form the tow is passed through a stuffer box crimper to impart crimp to the individual fibers. The crirnped tow may then be cut into staple or used for direct spinning into a yarn. In the latter case the tow may first be hot stretched and randomly broken on a Turbo Stapler, or randomly cut on a Pacific Converter, then spun into yarn.

Regardless of how the tow is to be used it is important that it be uniform in fiber properties and in fiber distribution. All the fibers should have the same crimp frequency and the same crimp amplitude or crimp index. The fiber density should be constant across the tow and the fibers should be intermingled to the same extent throughout so that the tow will be coherent. The individual fibers should not be damaged or broken.

One common fault of the tows which causes difiiculty in converting into uniform yarns is their tendency to split apart. Another is the appearance of thick and thin spots in the tow, often associated with split tows, damaged fibers, and unevenly crimped fibers.

In order to produce spun yarns and fabrics of uniform appearance and uniform properties it is necessary to make a uniform tow. To make a uniform tow, it is necessary to form the same from ribbons which have an essentially uniform thickness throughout their width, whereby they can be laid out side by side without gaps, thin places, or overlapping, unduly thick places. The practical problem arises from the fact that ordinarliy moving ribbons of filaments tend to acquire a more or less pancake cross section. That is, they are thick and reasonably uniform throughout the major portion of their width but tend to thin out at the edges.

Heretofore, little effort has been made to control the width, thickness or shape of ribbons that go into the formation of tow. In some cases, ribbons of textile filaments have been passed between pins or posts spaced apart for a distance slightly less than the width of the entering ribbon of filaments. Such passage, however, does not permanently constrict the width of the ribbon, and the edges spread out to essentially their original width and thinness immediately after passing through the pins.

Accordingly, it is an object of this invention to provide apparatus for shaping the cross section of a moving ribbon-like mass of essentially aligned, loose, continuous textile filaments whereby to impart thereto a lasting, essentially rectangular cross section of reasonably uniform thickness throughout its width. Other objects and achievements of this invention will appear as the description proceeds.

In a general way, the objects of this invention are achieved by passing the moving ribbon-like mass through a rigid body which comprises an essentially U-shaped 3,277,537 Patented Oct. 11, 1966 channel portion therein, said portion having considerable extent along the line of the moving filament mass, compared to its width. In other words, while constricting the ribbon laterally in essentially the same manner as a pair of pins would, the apparatus of our invention holds the mass in its constricted form for a measurable interval of its travel, whereby the individual edge filaments which have been crowded together are given a chance to enmesh, intertangle or otherwise acquire an influence on each other to make it easier for them to stay together than to separate.

The required length of the channel portion for the aforegoing purpose cannot readily be expressed with reference to its width or the width of the passing ribbon, because ribbons will differ in width over a wide range in different plants, or from one time to another in the same plant, depending on the needs of the particular production. The constrictive effect of the channel walls, however, exerts its influence principally on filaments lying close to the edge (say Within A: inch from the edge), there being no transmission of force from the edge filaments inwards until the edge filaments have become excessively crowded. It is possible, however, to define the requisite length of the channel in terms of its time of contact with the moving ribbon. We have found that satisfactory results are obtained, if the length of the restricting channel is such that it is in contact with the moving ribbon for at least 0.002 second. For instance, if the ribbon moves at the rate of 7 yards (6.4 meters) per second, satisfactory results are obtainable with channels which will provide from 0.5 to 10.0 inches (1.27 to 25.4 cm.) of contacting length with the ribbon.

For a clearer understanding of this invention, reference is now made to the accompanying drawings, in which:

FIG. 1 is a diagram in two parts, a and b, to illustrate the fundamental observations on which this invention is based.

FIG. 2 is a perspective View of one form of this invention, situated in a position for passing therethrough a vertically moving ribbon.

FIG. 3 is a perspective view of an assembly of the channels of this type on the inside wall of the last tank of a wash-draw machine, whereby a plurality of the washed ribbons are withdrawn from the tank, side-by-side, in a vertical direction.

FIGS. 4 and 5 are, respectively, a top view and an end view of another form of this invention.

FIG. 6 is a side view of a bank of guides of this modified type arranged in a vertical frame for transmitting a plurality of essentially horizontal ribbons and simultaneously changing the course of each individually so as to direct the assembly toward a single stacking (i.e. tow forming) device.

FIG. 7 is a side view of still another modification of this invention, showing a bank of guides in which each member is essentially a full-circle spool and the entire bank is mounted on an axle for free rotation in suitable bearings.

FIG. 8 is a vertical section along line 8-8 of FIG. 7.

Taking up now the drawings in detail, part a of FIG. 1 shows the behavior of a ribbon like mass 1 of essentially aligned, discrete and continuous textile filaments as it passes through two restricting pins 2, Z, in the direction of the arrow. Immediately after passing, the ribbon spreads out to essentially its initial width, as indicated at 1a.

In part b, the same type of a ribbon 1 is passed in the direction of the arrow through two restricting walls 3, 3 of substantial extent in the direction of the ribbon movement. The emerging ribbon then retains its restricted width for a considerable distance as indicated at 1b.

The remaining figures deal with several mechanisms according to this invention for putting the above observations to practical use.

.Theembodiment shown in FIG. 2 has a solid or hollow base portion 10, drilled at 11 for mounting on a horizontal shaft 12 and provided with a set screw 13 for fastening the base to said shaft. Extending forward from the base are sidewall portions 14 which together with face 15 form a channel for shaping a filamentary ribbon as the latter is passed through the channel.

Because of its simplicity of structure, this modification is best suited for use on the inside of the washdraw tank, and may for this purpose be mounted, through shaft 12 and brackets 16 on the inside of wall 17 of the lasttank in a wash-draw system, as shown in FIG. 3.

In this modification of FIG. 2, the floor portion .of

the channel is constituted by the flat, vertical face 15 of base 10, and the ribbon moves through the channel in a straight line.

In the modification shown in FIGS. 4 and 5, the rib bon moves around the circular shank 21 of a spool like 'rnember 20, whose flanges 22 may or may not run completely around the shank, but should extend at least over an arc of sufficient magnitude to provide lateral support for the moving filamentary ribbon for an interval of time not less than the minimum above indicated. As

a thumb ru-le generalization, it is recommended that the flanges extend for somewhere between 20 and 180 of arc.

Each spool'20 may he adjustably fastened over a horizontal shaft 23 which projects from a vertical backplate 26, in turn fitted to slide over a vertical post 27 (FIG. 6). The flanges 22 are made slideable over shank .21; screws 24 and longitudinal slots in the broadened tops of said flanges serve. simultaneously for fastening the flanges at an optional distance from each other and for fastening the entire spool at an optional distance from back-plate 26. Or, if desired, positioning with respect to the back-plate may be achieved by means of a slideable, arcuate supporting plate, as shown in FIG. 2 of J. C. Resors US. Patent Number 3,145,429. A

'plurality of spools 20 may in this fashion be spaced off plurality of them into a single tow.

In FIGS. 7 and 8, the entire plurality of guide channels is mounted on a single horizontal shaft 30 which -is mounted for rotation in suitable bearings. Each spool 31 possesses a shank portion 33 which can slide for the purpose of proper positioning over a horizontal barrel 32 and is then fastened to said barrel. The latter is fastened to ax-le 30 and rotates therewith. The flanges of each spool run in a complete circle around shank 33,

one of them (for instance flange 34) being made integral with the shank if desired, while the other one '(35) is made slideable over shank 33 and is provided with a set screw 36 for fastening it in a selected position on shank 33.

This modification may be used either inside the last .tank of the wash-draw system or at any subsequent stage in moving the ribbons toward the stacking rolls for making tow, and has the advantage over the other modifications that, because of the rotatability of the spools, wear upon them is at a minimum and they stay accurate for a long time. It will be understood that the drawings above discussed are merely illustrative and are not entended to limit the invention. For instance, while the walls 14 of the U-channel in FIG. 2 have been shown as rising perpendicularly from the bottoni 15, they may deviate slightly from the perpendicular, say an angles up to 15 outwards, so that the two walls may diverge with respect to each other at a total angle of up to 30. The same is true of the flanges shown in the spool-like modifications of FIGS. 4 and 7. Other variations and modification of this invention will be readily apparent .to those skilled in the art.

We claim as our invention:

Apparatus for shaping the cross section of a moving ribbon-like mass of essentially aligned, loose, continuous textile filaments of an initial cross section which is thinner at the edges than in the middle, whereby to produce a ribbon of substantially uniform thickness throughout its width, which comprises a rigid body having an essentially U-shaped channel portion therein, said channel por- 'tion having a floor portion and sidewall portions and being positioned in the path of the ribbon whereby to intercept and confine said ribbon for a stretch along its path, the sidewalls of said channel portion being spaced apart at a distance equal to that estimated for the width of the desired, uniformly thick ribbon and having a sufiicient extent in the direction of the motion of the ribbon to contact the edge portions of said ribbon for a period of time not less than 0.002 second, said channel being formed by a segment of an essentially spoollikerbody having adjustable circumferential flanges, said flanges each having a slot therein, and screws oper-ably associated with said slots to allow individual adjustment of said flanges in the axial direction of said spool.

References Cited by the Examiner UNITED STATES PATENTS 2,208,174 7/ 1940 Weinberger. 1 2,345,544 3/1944 Worthington.

2,377,173 5/1945 Nelson 24'2.-157 2,621,376 12/1952 Cottom et al. 19-157 3,130,453 4/1964 Haigler 19-65 3,131,843 5/1964 Bentley 226--l96 X 3,145,429 8/1964 Resor 19157 3,231,958 2/1966 Chadwick 19- -150 X ROBERT'R. MACKEY, Primary Examiner.

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