US2925627A - Textile combing and other machines - Google Patents

Description

Feb. 23, 1960 w. NUTTER TEXTILE COMBING AND OTHER MACHINES Filed April 28, 1954 5 Sheets-Sheet 1 Wm m a, ,w,

Feb. 23, 1960 w. NUTTER 2,925,627

TEXTILE COMBING AND OTHER MACHINES Filed April 28, 1954 3 Sheets-Sheet 2 IIVVN R WA: 15/? V0 TI'ER M, M 0144mm Feb. 23, 1960 w, NUTTER 2,925,627

- TEXTILE COMBING AND OTHER MACHINES Filed April 28, 1954 3 Sheets-Sheet 3 wm-w 70/ 11/41. re 775/? B M M 0m;

United States atent O r TEXTILE COMBING AND OTHER MACHINES Walter Nutter, Water-foot, Rossendale, England, assignor to T. M. M. (Research) Limited, Oldham, England Application April 28, 1954, Serial No. 426,168 Claims priority, application Great Britain July 29, 1953 3 Claims. 01. 19-130 Variation in thickness of a textile sliver may be broadly identified as either of random or periodic type. Variations may be due to random fibre arrangement and more particularly may be caused by incomplete control of the shorter fibres in a drafting system; it is almost invariably present in all drafted or drawn slivers. Periodic variation, on the other hand, may be caused by mechanical imperfections in a machine, or by an inherent characteristic of a machine such as the intermittent piecing operation in a rectilinear textile combing machine.

Rectification of known mechanical imperfections will frequently eliminate the periodic variation, but if they are small they may be diflicult to trace and correct. Especial ly serious however, are variations which arise from an inherent characteristic of a machine, since their correction is usually impossible.

The present invention is concerned with slivers having a periodic variation and particular attention is given to the effect thereonof the process of drawing and doubling of which considerable use is made in the treatment of textile slivers preparatory to spinning, special reference being made (a) to the delivery of a textile combing machine where reconstitution of the combed tufts into a continuous web by the over-lapping piecing operation which is an essential characteristic of these machines produces a serious periodic variation, and (b) to the drawframe by which combed slivers are prepared for the first spinning operations. The invention has proved to be particularly applicable to the processing of combed cotton.

In a combing machine we have found that the periodic variations present in the head-slivers are amplified by the frictional drag of the surface of the table upon which the slivers from the several combing heads are assembled and along which they are passed to the draw-box for reduction by a combined doubling and drawing operation into a single sliver. We have also found that even though the variations in the thicknesses of the several head-slivers are not in phase when said slivers are assembled, there is a tendency for the variations to be brought into phase during their passage through the draw-box, so that the output sliver exhibits a periodic variation of considerably greater amplitude.

We have ascertained that the wave-length of the variation in thickness of the output sliver is a direct function of the piecing wave in the individual head-sliver and the degree of draft introduced at the draw-box, and that the amplitude of the variation in the output sliver varies according to the quality of the piecing (i.e. the amount of overlap in the piecing) effected at the combing head.

Although the characteristic wave may disappear in the draw-box output sliver if a particularly good piecing is produced, we find that with an indifferent piecing a large amplitude periodic irregularity will persist indefinitely, the wave-length of the period being measured by the product of the piecing length and the draft introduced at the drawbox.

A possible explanation of the aggravation of the irregularity by the passage of the slivers through the draw-box 2,925,627 Patented Feb. 23, 1960 is that the effective diameter of a pair of cooperating rollers (such as drafting rollers) is increased according to the thickness of the material passing between them, so that there is a tendency for thick and thin slivers to be drawn forward at differential rates, and where a plurality of slivers are passed side-by-side through several successive pairs of drafting rollers, with their periodic irregularities out-of-phase on entering the nip of the first pair of rollers, the differential action of the rollers has a selective effect, tending to bring the periodic variations into phase by the time the slivers reach the last pair of rollers, and a large-amplitude variation in the output sliver results.

The passage of the draw-box output sliver through a conventional draw-frame has the efiect of producing a further variation having a wave-length measured by the product of the comber draw-box wave-length and the draw-frame draft. Thus, the effect of a bad comber piecing is not only amplified at the comber draw-box but is reflected in subsequent drawing operations with progressively greater Wave-lengths at each stage.

Whilst a satisfactorily regular draw-box output sliver can be produced from an exceptionally good piecing in the comber head slivers, with almost complete elimination of the characteristic large amplitude periodicity, it is difficult and indeed almost impossible to achieve such a high standard of piecing, in actual mill conditions. Furthermore, attempts to prevent phasing of the comber head sliver variations by use of staggered bollards on the draw-box table, or diagonally disposed drafting rollers in the draw-box, have proved unsuccessful.

As it was evident that phasing had occurred in the draw-box itself and since it appeared that this might be caused by passage of the slivers between multiple drafting rollers, the presentinvention is based upon a realization that to reduce the tendency for thin and thick places to get into phase, the number of rollers used in the comber draw-box should be reduced to a minimum.

The present invention consists in simultaneously treating a plurality of textile slivers containing periodic variations of thickness by subjecting the slivers to asingle drawing stage in apparatus comprising not more than two successive pairs of rollers rotating at constant speed (of which the second pair has a higher surface speed than the first pair). It is found that the limitation of the drawbox of a combing machine, or the drawing head of a draw-frame operating on combed slivers to only two pairs of rollers, i.e. one pair of holding rollers and one pair of drafting rollers, is effective to reduce periodic thickness variations, and that the periodic irregularity which is characteristic of slivers which have passed through the conventional multi-stage drawing apparatus is almost entirely absent.

Embodiments of the invention are hereinafter described with reference to the accompanying diagrammatic drawings, of which Fig. 1 is a side elevation of the draw-box of a rectilinear combing machine, Fig. 2 a plan thereof with the upper rollers removed, and Fig. 3 a side elevation of a draw-frame.

The combing machine draw-box illustrated in Figs. 1 and 2 comprises two spaced side-frames 10, 11 between which are mounted two pairs of drawing rollers arranged in tandem, the first pair consisting of the lower roller 12 and upper roller 13 and the second pair consisting of the lower roller 14 and upper roller 15. The rollers of each pair are mounted between vertical guides formed by slots 16 in the side-frames so as to be capable of a limited degree of relative vertical movement as required by the thickness of the sliver as it passes between the rollers.

The sliver is fed along the plate =17 to the first pair of rollers 12, 13 and after undergoing drafting by the second pair 14, 15 it is delivered through the funnel 18 and calender rolls 19, 20.

The requisite loading pressure is applied to the upper rollers 13 and 15 through the medium of a rectangular frame 21 which is pivoted upon the side frames at 22 and which incorporates spring-pressed plungers 23, 24 which are adapted, when the frame 21 is securedin the operative position shown in the drawings by the catches 25, 25, to bear downwardly upon the arbors of said upper rollers. The catches 25 are fixed upon a transverse rod 26 which can be rotated for the purpose of engaging or releasing said catches by means of a handle 27.

The roller 12 receives its drive through the gearing 28, 29, 30, 31 and 32 from the driven shaft 33, and the roller 14 is driven at a higher surface speed than the roller 12 by the driven shaft 34 through the gearing 35, 36 and 37.

' The rollers 12, 13 are conveniently mounted in members 101 and 111 which are slidable on the side-frames 10, 11 in the direction of the path of the sliver, so that the distance between the nip of the rollers 12, 13 from that of the rollers 14, 15 may be adjusted as desired.

The draw-frame illustrated in Fig. 3 comprises the conventional roller-stand 40 on which are mounted the usual assisting rollers 41, 42 and two pairs of drawing rollers, i.e. the first pair consisting of the lower roller 43 and upper roller 44, and the second pair consisting of the lower roller 45 and upper roller 46. The second pair of drawing rollers 45, 46 are mounted in a stationary bearing-block 47, whilst the assisting rollers 41, 42 and the first pair of drawing rollers 43, 44 are mounted in bearing-blocks 48 and 49 respectively which are capable of sliding movement towards or away from the rollers 45, 46, thereby making provision for varying the distances between the several pairs of rollers to suit the staple length of the fibres under treatment.

Each of the aforedescribed machines incorporates only a single drafting zone, i.e. between the rollers 12, 13 and the rollers 14, 15 in the case of the comber draw-box, and between the rollers 43, 44 and the rollers 45, 46 in the case of the draw-frame. By these means periodic irregularities in the thickness of a processed sliver are nearly completely eliminated.

The slivers are not again subiected to concurrent drawing, without first abandoning the phase relation which exists between slivers at the conclusion of the single drawing operation. At any subsequent drawing operation the slivers can be deliberately started out of phase, or the matter of phase can be left to chance. I

What I claim as my invention and desire to secure by Letters Patent is: a 1

1. A method of treating a plurality of textile slivers containing periodic variations of thickness, the variations in the respective slivers being relatively out-of-phase, consisting in subjecting the slivers simultaneously to a single drawing operation performed by passing the slivers side by side through no more than two successive pairs of rollers rotating at constant speed, the second pair having a surface speed higher than that of the first, the slivers passing directly from the first pair of rollers to the second pair, and thereupon combining the independently drawn out-of-phase slivers into an output sliver.

2. A method of treating textile fibres consisting of the steps of simultaneously performing a combing operation on each of a plurality of laps of the fibres of such nature that there is a tendency to produce in the slivers periodic variations of thickness which are out-of-phase with one another, and subjecting the resultant combed slivers to a single drawing operation performed by passing them side by side through two successive pairs of rollers rotating at constant speed, the second pair having a surface speed higher than that of the first pair, and the slivers passing directly from the first pair of rollers to the second pair, and thereupon combining the independently drawn out-of-phase slivers into an output sliver.

. 3. The method according to claim 1, wherein the staple length of the fibres is 2%" or less.

References Cited in the file of this patent UNITED STATES PATENTS 874,715 Westcott et al Dec. 24, 1907 1,722,006 Nigrin et a1 July 23, 1929 1,973,552 Williamson Sept. 11, 1934 2,199,842 Schlums May 7, 1940 2,412,357 Robinson Dec. 10, 1946 2,705,423 Strother et al. Apr. 5, 1955 2,738,554 Whitehurst Mar. 20. 1956

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