US2645822A - Drafting textile fibers - Google Patents

Description

1953 w. J. cABANA I 2,645,822

DRAFTING TEXTILE FIBERS Filed Dec. 10, 1946 8 Sheets-Sheet l COMBINE MACHINE SLJVER -6 ENDS P|N DRAFTER 11/ COARSELY DRAFT 6T0] Pl N N ED '*6 EN D5 SECON o PIN DRAFTER v s EN 05 1 THIRD DRAFT 6.8TO1

13'?" PIN DEAF-Til f4 ENDS PIN DRAFTER 14 FINELY DRAFT 7T0] PINNED DRAFT 6.5T0 1 CONE ROVER DRAFT 7.5TO1

DRAFTING AND DRAFT H4 T01 FRA M 'E SPUN WORSTED YARN mmvr w| LFRED J. CABANA.

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July 21, 1953 W. J. CABANA DRAFTING TEXTILE FIBERS 8 Sheets-Sheet 2 Filed Dec. 10, 1946 WILFRED 1 5? A.

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July 21, 1953 w. J. CABANA DRAFTING TEXTILE FIBERS 8 Sheets-Sheet 3 Filed Dec. 10, 1940 INVENTOR.

WILFRED J.CABANA. BY fl t w MORNEIS July 21, 1953 w. J. CABANA 2,645,

DRAFTING TEXTILE FIBERS Filed Dec. 10, 19.46 8 Sheets-Sheet 4 INVENTOR. WILFRED J. CABANA. BY A 0 J77? Rm.

July 21, 1953 w. J. CABANA DRAFTING TEXTILE FIBERS Filed Dec. 10, 1946 8 Sheets-Sheet 5 INVENTOR. WILFRED J. CABANA.

y 21, 3 w. J. CABANA 2,645,822

DRAFTING TEXTILE FIBERS Filed Dec. 10, 1946 8 Sheets-Sheet 6 INVENTOR.

IWILFRED J. CABANA.

3 w. J. CABANA 2,645,822

DRAFTING TEXTILE FIBERS "iled Dec. 10, 1946 8 Sheets-Sheet '7 INVENTOR. WI LFRED J. CABANA.

AZTORAIEYS.

Patented July 21 1953 Wilfred J. Cabana, Woonsocket, R. I., assignor to Uxbrid'ge Worsted Company, Inc., Uxbridge,

Mass, a corporation of Massachusetts v Application December 10, 1946, Serial No. 715,329

1 This invention relates to drawing textil fibers and pertains particularly to the worsted art.

The invention concerns generally the attenua tion of strands of loose fibers, uch as slivers. and rovings and treatment thereofito pi'oduceyarns, threads and the like, which are suitable for being made into textil fabrics,

The invention has amongits objects" the production of improved yarn, which hasa; better appearance, is stronger and. has less fwild fiber than heretofore obtainable, and in which the fibers are substantially parallel andgive a soft, lofty efiect. f

It is also an object to produc any of a wide variety of blends of different fibers, differing not only as to length of fiber, .weight, thickness and other physical characteristics, but also differing as to origin and whether natural or synthetic, or derived from animals or plants. I

Furthermore, it is an object to provide arrange-' ments for drawing such fibers rapidly, at relatively little expense, very nearly 'withoutbreakage and substantially without stressingthe fibers, or slivers,'r'ovings, slubbings and the like, beyond their elasticlimit.

Moreover, it is an object to produce yarns hav ing thequallities of yarn produced by the socalled French or continental system of worsted production, while employing even feweriopera tio'ns than involved in the so-called English or Bradfordsystem, or other modified systems here tofore proposed for obtaining the French ."soft I roving's. i

A further object'is to provide methods and ap-- paratus for drawing fibers which are of general utility and not limited to the worsted art, and still J another object is to provide ready adjustability for the most efficient processing of different fibers and blends of fibers.

Other and further objects, features and advantages of the invention will become apparent as the description proceeds. I

In carrying out the invention while drafting strands of fibers, such as slivers, rovings and the like, fiber control is maintained continuously throughout the drafting area. To this end durmg each passage of the fibers, through successive processing units, the fibers of the incident 24 Claims. (o1. 19-131) drafting area, by pressure applying members located along the path of the strand to engage thetraveling strand continually duringits passage through the drafting area. v

In accordance withthe invention the fibers are maintained loose, and in substantially untwisted condition, throughout the worsted process until the fibers are spun in the final step of the process of fabricating yarn. This produces a lofty yarn,

without sacrificing strength. The drafting of strands of fiber under continuous fiber control 'throughoutthe length of the drafting area enables the strands to be processed readily 'untwisted condition.

Heretofore, in the fabrication ofworsted yarnj it has been the practice to takea batch of wool fibers from storage space containing a predetermined blend and to scour, card andcomb them.

The batch leaves the combing machine in'the form of a sliver, which isfree from lumps,

bunches "and foreign matten-and inwhich the fibers lie substantially parallel. The product of the combing machine according to the prior practice is given several gilling operations to produce material in the formknown as tops. 7 The f tops are given several passages through drawstrand are maintained under lateral pressure or ing frames, twoqor more passages being through gill boxes which are particularly designedto parallelize the fibers. This and other operations,

including doublings, are to obtain a level end.

spinning of the yarn.

Under one system of the' prior art worsted process, tops are given two or'more passages through gifll boxes, and. these passagesare followed by sev'eral through drawing frames, such All these operations arepreliminary to the final as finishers, reducers and rovers,- which' do not includegill boin'es. In each of the latter drawing frames, the attenuated product strand of fibers is twisted, and wound on bobbin in the twisted condition. Ineach next sucoeeding'passage, the

twist is substantially removed during the draft-' ing operation, it being necessary thatthe' fibers be directed longitudinally its attenuation. v e

The object of twisting the product strands-tr certain passages in the prior'art p1-auce 1sm control their fibers during and between the various operations of the process. For a similar purpose, false twist is usually applied to the of c the strand during I 3 product sliver of the passage through a gill box, the sliver in false twisted condition being packaged into a ball. The false twist is also removed in the next succeeding passage, whereby the strand is in an untwisted condition when it is being attenuated.

In accordance with the present invention, I avoid twisting the product strand of the given passage and removing twist in the drafting operation in the next succeeding passage. Among other advantages obtained in accordance with the present invention is the elimination of the loss of piece-up waste.

I have discovered that an improved worsted yarn can be made with fewer operations when fiber control is maintained continuously during each drafting operation. Beginning with the product sliver of the combing machine, instead of with tops as in the prior art practice, the strand is given a number of passages including doublings, for the desired blending to get a level end. The strand is gradually reduced in successive passages, or may be substantially reduced in one of the passages, the last passage under one practice of the process of the present invention, producing a roving which is ready for spinning. The passages which include doublings are preferably all through drafting frames which embody pin drafting machines. These machines are similar in their general principle of operation to gill boxes well-known to those skilled in the art. None of the passages which include doublings are through drawing frames like the finishers and reducers of the prior art, which twist the product strand. Accordingly there is no pieceup in carrying out the present invention.

The product sliver of each passage, even though it is in untwisted condition, does not lose fiber control after it leaves the drafting area. The fibers continue under control with normal handling of the strand in the manner hereinafter described up to the drafting operation of the next passage where means are again provided for positively maintaining fiber control. The really critical time when fiber control is likely to be lost is when the strand is being worked, attenuation of the strand constituting the principal working in the worsted process which is severeenough to cause the loss of fiber control. I

A fabric woven of the loftier yarn produced in the practice of the present invention is fuller than Bradford yarn and equal in fullness to French yarn. The fabric is stronger, its component yarns being stronger than prior art yarns. As high as 15% greater strength hasbeen observed in yarns of comparable fiber content and count, and yarns for comparableuse'in fabric, than has heretofore been obtainable in the customary worsted processes.

Under the prior art worsted process, the length of ratch is adjusted for control of fibers in the drafting area, the adjustment being in accordance with the length of fibers in the given batch. A short ratch is used for a batch of short fibers and the ratch is lengthened accordingly as the batch contains longer fibers, or a greater percentage of long fibers. In a batch of long fiber wool, for which a long ratch is 'used, there is a tendency to lose control of the shorter fibers, with a resultant tendency towards bunching, and also a loss of fibers in fly waste. In the case of a batch of short fiber wool, for which a short ratch is used, fibers which are longer than the length of the ratch are subjected to lacerating tension, which breaks them.

Therefore, under prior art practice, a blend of fibers is prepared with a predetermined degree of uniformity of fiber length, and the ratch is adjusted in accordance with the predominant length of fibers in the batch taken from a given blend. However, in a blend of fibers, either short or long, there will be some fibers which ar longer than, and others which are shorter than, the desired or predominant length range or gradient. Grades of wool are, accordingly, selected for a blend to have a low percentage of fibers which are shorter and longer than the predominant length range.

In practicing the present invention, there is continuous fiber control throughout the length of the drafting area, there is no limitation of the range of fiber lengths that may be contained in the batch of fibers being processed. With means provided along the path of the strand in the drafting area to apply fiber controlling lateral thrust continuously, the shorter fibers of the batch are held under control. Not only is the ratch adjusted long enough to avoid lacerating back draft tension being applied to the longest fibers, but a soft control is employed. Gradually increasing lateral pressure is applied to the strand for gradually increasing resistance to movement thereof, so that there is no danger of breaking the longest fiber, and the shortest fibers are held parallel to the others and within the strand. The permissible diversity of fiber lengths, in carrying out the present invention, is so versatile that it is feasible, for example, to blend cotton and wool fibers, and to fabricate yarn of blended cotton and wool under the new worsted process of the invention, although cotton fibers are relatively short in comparison with wool fibers. It is also feasible to blend a wide variety of natural and synthetic fibers, different in length and in character of fiber.

When a blended yarn is desired under prior art practice, for example, when a yarn is to be fabricated of different types of fibers which, by way of illustration, might be wool and a decorative rayon fiber, the blending is usually begun in the doublings of tops. Packages of the various types of fiber, which have previously been prepared to have uniform fiber length in the different packages of different types of fibers, are fed as several ends in a passage through a gill box. The wool fibers are supplied 'in the form of tops, which are the product slivers of the combing machine, after they have been given two or more finish gilling operations. The finish gilling of tops is not unlike later passages of tops through gill boxes in continuance of the worsted process, and in fact constitute the first of several drafting passages of the prior art practice of fabricating worsted yarn.

The worsted process of the present invention preferably begins with the sliver product from the combing machine, and begins before the finish gilling operations which produce tops. For example, if a blended yarn is desired, slivers of the various types desired in the blend are fed to a pin drafting machine as the several ends of doublings, the wool slivers being fed from cans, in which they were received directly from the combing machine. Thus, blending of all the fibers which are being fabricated into the yarn is begun simultaneously with the blending of the several grades of wool fibers contained in the woolbatch.

A better understanding of the invention will be afforded by the following detailed description considered in conjunction with the accompanyingdrawing,inwhich:

Fig. l is a block diagram representing an illustrative combinationof units to form: adrafting system and diagrammatically method employed; a

Fig, 2 is a schematic diagram' 'in side elevation representing a pin-drafting inachinewhich may be employed .-1

Fig. .3 is a fragmentary assembly-drawing in elevation of a frame for drafting and spinning.

the rovings;

i is a fragmentary type rovingdrafting head;

Fig. 4a is an enlarged fraginentaryview of a Fig; 9 is a schematic diagramof the apparatus of Fig. 8, representing outlinescut by a series of vertical planes; g, a I

Fig. 10 is a diagram of sliver cross-sections at successive positions in the apparatus of Figsrd and 9 but drawn to an enlarged scale; 1

.Fig. 11 is a side elevation of a portion of the apparatus shown in Fig. *7, with a modified bearing block for the free-running ratchroll, and

the addition of a switch responsive to breakage of the strand being'drafted for the purpose of interrupting the su'pplyof strand to the draft control aprons; I

i Fig. 12 is a fragmentary-view of the 'apparatus of Fig. ll with certain. portions thereof broken away to expose a sectioncut by the p1ane l2- l2 indicated in Fig. '13, and showing the parts in a position assumed after albrea'kage in the strand has occurred; and *4.

Fig- 13 isa fragmentary'top viewoftheportion of the apparatus of Fig. 11,. controllingthe free-running ratch rolls.. 1

Like reference characters are utiuzed throughout the drawing to designate like parts. 7

As indicated schematically in Fig l of the drawing, the "process of the p-resent invention commences after they fiberhas ,left'the combing machine in the form. of slivers. The sliver, combed in suitable apparatus, of conventional type, ispassed through'a pluralityof pin-drafting machines, for exampla'two to four such machines, then preferably passed through cone rover, and finally through a drafting and spinning frame employing a 'novel type ofdrafting headforming' a part of my invention. Aswill be described in greater detail hereinafter, the pinning of the pin-drafting machines is preferably made progressively finer. A number of ends are applied to each-pin-drafting machine so as to obtain a desired number of doublings. Thus a plurality-cf slivers, .for. .examplesix's'livers, are iedto va pin-drafting machine I I in which pins are relatively widelyspaced in comparison with subsequent pin-draftin machines." The product of the relativelyfcoarsely pinned draftin machine H is supplied to a can and such a product indicating theside view of my apron I with further doublings, forexample sixends up,

with five. ends up; and. the product. of the'third pin drafter I3 is, inturn, supplied to amore finelypinneddrafting machine M, with a suitable number of ends up, for example four. The productof the final pin'drafter H may eitherbe spooled or supplied to a canjaccording to the 1 preferredoperation, from which the sliver'isapplied preferably to a conerover [5. the output of.

which is spooiedand in turn supplied to the drafting and spinning'frame l6; 1

. Each of the pin :drafter'sl Ii. to M inclusive,

comprises briefly a set of faller points l7, adapt-i ed to be moved-in the direction of the arrow I8 Withmeansfor delivering thereto a plurality of slivers or of strands of :fiber l9from cans 2|;

Drafting- rollers 22, 23 and 29 are provided for drawing 'theconsolidated sliver 24 through the faller points i l and delivering them through condensers.25' and 26 to a conventional coiling head- 21 of a receiving can 28. The arrangement is I such as to maintain fiber control at all times during the passage of the fiber and especially .to 'hold or support thefibers at closely'spaced pointswherever the fibers are being worked. For example, for the sake of more closely" nipping the fiber after leaving the faller points H, the nip roll 29 of relatively.- smalldiameter is placed in very close proximity to. the delivery end of. the bed of faller points ll so as to press thefibers against the upper draft :roll 22 and thereby provide a closer nip than could be obtained from the larger diameter rolls'22 and.23.- The general arrangement-of the pinsyor faller points. in the faller point bed H, the method of moving them, and

Satisfactory results have be'enobtai n'edby em ploying apparatus taking either of two'difierent forms to serve as the cone rover l5, indicated schematicallyin Fig.1. For example, I may employ a conventional type of cone rover, emp'1oy-' ing roller drafting and'driven :fiyers in connection with bobbins, on. which I the rovings are wound; Such a cone rover may be of the type, for example, illustrated in Fig. 84, on page 258' of Manufacture of Woollen andWorsted Yarns, by' J. W. Radcliffe (second edition), published in 1924 by Emmott andCo and described'in chapter 20, pages 229110-247 of Radcliffe. .In this case the final pin 'drafter i4 is preferably-jofthe; type known as a spindle ,gill arranged to produce a minimum twist for which aspindle gill is-capable of adjustment. Such a spindle gill includes a bed of fallerpoints H, as indicated-in Fig. 2,

with a driven fiyer winding the sliver 24 on a drag bobbin instead of employing a receiving can 28. The flyers, however, are driven at such speeds as to produce relativelylittle twist in comparison with previous practice in worsted drafting.

Alternatively the cone rover limay are modified form employing a carrier apron drafting head with a fiyerspinner adjusted for very littletwist; In this-case, the cone rover is fed from rotatingcans instead of from a plurality: of:

supplied to the third pin drafter I3, forexampld- For example, the arrangement may be 1 wound bobbins carried on a creel board. Accordingly, the final pin drafter II will then be of the type illustrated in Fig. 2, feeding the sliver 24 into the receiving can 28. For a maximum degree of loftiness and softness of fiber desired, the latter type of cone rover is advantageous inasmuch as the delivery cans may be set for a negligible speed of rotation so as to impart substantially no twist to the sliver processed by the rover. Supplying the rover from rotating cans has the further advantage that with a set condition of the aprons, the amount of twist can be adjusted to suit the condition of the aprons 'and to suit the condition of the stock. The apron drafting head employed in such a ,cone rover may be of the type which will be described in greater detail in connection with drafting and spinning frames [6, except that in the cone rover, I preferably employ a drafting head in which the carrier aprons are substantially horizontal instead of nearly vertical.

The drafting and spinning frame 16, indicated schematically in Fig. 1, includes a plurality of drafting heads and spinning bobbins as illustrated in Fig. 3. Such a drafting head, illustrated for example in Figs. 4 and 5, comprises briefly a pair of conveyor and ratch rolls 3| and 32, the rear roll 3| being driven; a pair of draft rolls 33 and 34, the rear roll 33 being driven; and a pair of carrier aprons or belts 35 and .36, driven from the upper end in a manner which will be described more in detail hereinafter. A significant feature of the carrier aprons 35 and 36, where the apparatus is to be employed for drafting worsted, is the space shown at 31 in Fig. 4 between the confronting surfaces of the belt or apron at the upper end of the aprons 36 and 35. The invention is not, however, limited to the use of this spacing 31, and in drafting certain types of fibers, this feature may be eliminated. Snubbing bars 36 and 39 are provided for causing the confronting contact portions of the belts 35 and 36 to follow a serpentine path. Relatively narrow guide bars or strips 4| and 42 are provided at the lower ends of the belts 35 and 36 in place of rollers in order to permit the provision of fiber control at the lower end of the carrier aprons relatively close to the nip of the draft rolls, and also in order to provide for a soft pliable control at this lower end.

The conveyor or ratch rolls 31 and 32 are arranged for feeding a sliver 45 to the aprons 35 and 36. The draft rolls 33 and 34 are arranged for drawing a reduced .strand 48 from the aprons 35 and 36. The surface speeds of the pair of rolls 3| and 32, the pair of aprons 35 and 36, and the pair of rolls 33 and 314 are progressively greater so as to effect a desired degree of drafting. Various details of construction and additional advantageous features of the apron type drafting head will be described hereinafter.

As indicated in Fig. 3, a conventional type of spinning throstle of the ring type may be employed, having spindles 5|, driven by belting, not shown, engaging wharls 52 and winding yarn upon bobbins '53. The yarn is drawn through guide eyes 54 and travelers 55 carried by rings 56. Suitable conventional mechanism, not shown, is provided for raising or lowering either the rings 56 or the spindles 5| for distributing the yarn on the bobbins 53.

The worsted process for a given batch of fibers is set up for a predetermined numberof passages through pin-drafting machines, all essentially the same as illustrated in Rig. 2. Two to four passages are usually sufficient to produce a level end in the product yarn, and this is typical of the process of the present invention. The number of ends fed into each passage of the pin drafters will depend upon the number of doublings predetermined as being desirable for producing the desired blending in the passages. Six to eight ends are typical for any given passage, and the doublings for producing a given worsted yarn may be from 200 to 1,000, depending upon the blend of fibers in the batch. Drafts ranging from between 5 to 1 and 8 to 1 are typical for each passage, the draft of each passage being predetermined to level the strand and to reduce it the desired amount. The reduction through the several passages is to level and reduce the product strand through the last pin-drafting machine to a size suitable for the roving frame.

Under the prior art there are two principal systems for fabricating worsted yarns, known as the English or Bradford system and the continental or French system. Other systems are modifications of either of these or the combination of practice in both.

Under the English system, which is the simpler and less costly of the two, there are usually four or five successive passages through gill boxes from the comb followed by four or more successive passages through drawing frames followed by finishers, reducers and rovers. The latter drawing frames do not include gilling mechanism, and each operates to produce a product strand which is twisted and is wound on bobbins in twisted condition. In the later passages, in which the product strand is packaged in twisted condition for transfer to the next operation, there is a high percentage of piece-up waste.

The process of the present invention is more nearly comparable with the English system. These passages of the English system in which the product strand is twisted are not included in the new process, and there is no loss of fibers in piece-up waste. For production of comparable yarns, there are no more passages through gill boxes and ordinarily fewer passages under the process of the present invention than there are under the English system.

The other well known prior art system, known as the French system, uses finer grade fibers, and produces a loftier yarn, than the English system, which was devised as a worsted process for using all grades of fibers. The process of the present invention is capable of using all grades f fibers. The product yarn of the new process has a loftlness, quality and texture comparable with a yarn of the French system.

The French system as a process is not readily comparable with the process of the present invention. One characteristic feature of the French system is the employment of many passages through mechanisms known as porcupine rolls. these revolving rolls having steel pins arranged around the periphery. The French system requires many more operations than the English system, ranging from 9 to 14 passages under the French system, depending upon the'grade of yarn desired as compared to '7 to 9 passages under the English system. The French system is, therefore, inherently :more costly than the present invention.

The :followingare comparatlve tables of typical operations under the English system and the new llm if r producing yarns ofcomparable count;

Typzcal steps under the Englzsh 01' Bradford system OPERATIONS AFTER THE COMBING MACHINE Operation Draft Doublings Machine Remarks Gombing Mill:

1 18-24 7 1 18-24 Intersecting gill box. False lst finish gilling 01' tops,

twister to can. 7 2 4-6 6 72-144 Iutersecting gill box. False 2nd finish gillingoftops. Prodtwister, boiler. not is tops. Yarn Processing:

3 (1) 5-6 6 6 lntcrsecting or open gill box. 1st gilung operation. If dif- False twister to can. ferent types of fiber are I g blended, it is done in Blending Box. J 6 6 to 7 36 Two spindle intersecting or 2nd gillingopcration.

gpengillbox. Flyers Bob- 5 6 180 Open drawing box, twister, 3rd Drawing Box.

Flyers Bobbin. 4 6 720 Drawing frame. Bobbin 1st finisher.

winding fiyer. v 4 6 2880 .do 2nd finisher. 2 6 5760 do Reducer. l or 2 6 to 7 .do Rover.

1 5 to 8 Ring, Cap or Flyer spinning Product is yarn. fame.

Typical steps under practiceof invention OPERATIONS AFTER THE COMBINGYYMAOHINEL" Operation Draft igffi Machine Remarks 6 .6 6 Intersecting gill box. Qoiler to If different types of fibers are can. blended, it-is' done in this p operation. I 6 6.5 36 do. 5 6.8 180 do 4 7 720 Iutersectiug gill box.

Y can or to spindle drafter. l 1 7.5 Cone Rover. Preferably Product is roving, slightly V twisted I 1 7m 14 Ring, Cap or Flyer spinning frame. I I

l Io'rE.Ihe operation listed above as third is so listed'for better com parison with the present invention. Ordinarily,

the first two operations are considered preliminary to drafting; and operations 3 .to are considered as thefirst to eighth operations in drawing from tops to yarn. Doublings are counted from operation 3 (l), doublings in gilling oftops being disregarded.

In any drawing frame passage which does not embody a pin-drafting machine, for example in the passage of the spinning frame, it is advisable also to maintain continuous fiber control through-* out the length of the drafting area.

Pursuant to this purpose, in accordance with my invention I provide fiber control mechanism which extends to close proximity with the front drafting mechanism. For example, in a spinning frame, comprising a set of front drafting rolls, and a set of back rolls. or feed rolls, I preferably provide carrieraprons instead of carrier rolls be tween the front and back rolls, the carrier aprons extendingtowards' the' front drafting-rolls to close proximity with the nip thereof.

The pin-drafting machine, illustrated in Fig. 2 schematically, may take any suitable form and is not limited to the specific arrangement illustrated. Preferably, intersecting pins are employed as in intersecting types of gill boxes. For the sake of simplicity, however, only one set of faller bars i? is represented as in an open type of gill box. There are guide rollers Stand 58 for delivering slivers ififrom a plurality of supply cans 2! to a delivery apron or belt 59. There may be a Weight or tension roller 6| for press ing the slivers [9 into a combined mass 62 carried by the delivering apron 59. v

In conventional worsted gill box assemblies there. are usually movable ratch rolls mounted in a position approximately corresponding to that of the right-hand apron carrying roller 60. Such ratchrolls acting in conjunction with the faller {bars I? and the draft rolls 22 and 23 provide the desired draft: of the fibrsif In such a case, the taller bars I] are progressed'in the direction of motion'of the fibersata speed intermediate the "urface speed or the ratchrolls and the drafting rolls. In carrying out my invention, however, I prefer to omit su'ch' ratch'rolls'and to obtain the entire 'dra'fting effect as'a result of drawing the fibers through the faller pins 63 by means of the '5 draft rollsf'22, 2-3 and 29. 'To this end the length a throat 64, a longitudinal section of which has "the shape of outline indicated in Fig. 8B. The throat has a circular cross-section as indicated Fig". 9B.- Preferably a convex surface guide bar 65 is mounted in advance of the condenser 25 in sucha manner that the strand 24 is caused to rest upon the guideb'ar 65 prior to entering into 'the throatt' of the" condenser 25.v As indicated in Fig'.8A; the guide bar 65'may be pivoted upon a; shaft fifiwhich is interconnected or linked in a mannernot constituting a part of the present invention with a stop motion serving to stop delivery of-the'sliverto the'machine in the event of breakage; A light, balance or spring mech- --:a'nism,'n0tshown, is provided Where-the guide bar is'to'be mployedin conjunction-with a, stop 1 l mechanism. I have found that it is unnecessary to cause rotation of the condenser 25 although a rotating type of condenser may be employed if desired.

Heretofore in processing worsted through gill boxes it has been customary to impart an appreciable twist to the sliver after itleaves the faller points in order to provide adequate tensile strength to the sliver for handling preparatory to the next operation. However, in order to preserve the loftiness of the yarn and the parallelism of the fibers, I avoid such twisting. Nevertheless, I maintain adequate strength of slivers so that they may be handled in the receiving end delivering cans and passed through a succeeding operation, such as an additional pin-drafting operation or a cone-drawing operation. In order to avoid adhesion between successive coils of sliver in a supply can, I provide condensers 25 and 26 so designed as to fold in the selvage of the sliver and eliminate wild fibers or unevenness at the selvage. The condenser 26 has a throat 61 of elliptical cross-section, as shown in Fig. 9C. Preferably, the condenser 26 is so mounted that the major axis of the ellipse 61 is horizontal, where the flattened sliver 24 lies substantially in a horizontal plane in its passage through the faller points I1 and the draft rolls 22 and 23.

The draft rolls 22 and 23 compress the fibers so that the strand 62 formed from the combination of slivers |9 is flattened to a single tape-like strand 24. In passing over the convex upper surface of the polished guide bar 65 the strand 24 is given a slight crescent shape with drooping sides or selvage, as indicated at 68 in Fig. 10A. The minimum throat diameter of the condenser 25, shown in Fig. 9B, is less than the width of the fiat sliver 68, shown to a larger scale in Fig. 10, so that in passing through the trumpet 64 the selvages are gradually folded in and the sliver has a shape 69, indicated in Fig. 103, after passing through the throat 64. In the passage of the sliver toward the throat 61 of the elliptical condenser 26, the selvages are curled in, as indicated at H in Fig. 10B; and after passage 1.

through the elliptical throat 61, the selvages are further curled, as indicated at I2 in Fig. 100. In this manner the fibers are condensed and the selvages are protected. As a result of this treatment of the output of the pin-drafting machine and the continuous fiber control, maintained in the course of continuous operations, the fibers may be retained parallel and it is unnecessary to impart any twist to them, especially during the pin-drafting operations. stood that as the sliver is coiled by the coiling head 21 and drops in progressively displaced coils around the inner surface of the receiving can 28, the edges of one portion of the sliver tend to come in contact with the edges of another portion of the sliver and the folding-in of the selvages is, therefore, advantageous as it eliminates adhesion by the successive coils when the sliver is being drawn from the can after the can becomes a supply container corresponding to one of the cans 2| in a subsequent stage of the pin-drafting machines or in connection with an operation following pin drafting.

It is accordingly unnecessary to provide means for supplying a false twist to the product strand I2 delivered to the can 28. The supply sliver containers or cans 2| contain the product strands of the next passage, each container 2| comprising a supply end packaged in the manner hereinbefore described. As many supply sliver cans It will be under- 12 2| are placed at the feed end of the pin-drafting machine as there are ends required to obtain the desired number of doublings in the incident passage.

The strand 62 may contain some fibers which are so short as not to extend across the gap between the bed of faller points I! and the nip of the drafting rolls 22 and 23. The bulk of the fibers in the strand, however, operates to carry fibers along into the drafting rolls, including fibers which are shorter than the gap. Another factor to be considered is the tendency of the short fibers to lose parallelism due to working the strand in the drafting operation, and there is the companion tendency for short fibers to fall out of the strand, these being lost as fly waste. The use of a longer faller bed together with the close proximity of the inner nip roll 29 to the faller bed, in accordance with my invention, minimizes the tendency of the short fibers to lose parallelism and to fall out of the strand.

Under prior art practice, the nip of the drafting rolls of a Bradford roll drafting frame is usually located 2" or more away from the control rollers of the frame. Therefore, the percentage of fi'bers which are so short as not to span the gap between the support points and the nip of the drafting rolls is high. Accordingly, the tendency of fibers to lose parallelism is great, and there is a relatively high percentage of fiber lost as fiy waste. More important, control of the fibers is partially relinquished in the critical drafting area, cause bunching, which produces unevenness of the product strand of the incident passage. For this reason, under prior art practice, relatively many passages, including doublings, are deemed necessary to attain a level end, or the desired degree of uniformity in the final product yarn.

In carrying out the present invention, the nip of the drafting rolls 22 and 23 is positioned much closer to the retreat end of the bed of faller points I! than under Bradford practice. The gap between the faller points and the nip of the set of drafting rolls is preferably to 1% as compared to the 2 or more under Bradford pracice. 7

A greater percentage of fibers in the strand 62, therefore, are long enough to span the gap between the bed of faller points l1 and the nip of the set of drawing rolls, to thus be under positive control of the faller points I! while they are being drafted. The corresponding smaller percentage of fibers in the strand 62 is so short as not to span the gap between the draft rolls and the faller points, and this reduced percentage of short fibers is so low that there is a greatly reduced and negligible loss in fiy waste in practicing the present invention. A more important result, as previously noted, is that the product strand of each of the several passages is more uniform because of continuous fi'ber control in the drafting area.

It should be understood that the gap between the bed of faller points I! and the nip of drafting rolls 22 and 23 need not be reduced to less than the length of the shortest fibers in the sliver. There is mutually cooperative fiber control between fibers, incident to the lateral thrust exerted by fibers upon each other. Those fibers which do not span the gap between the bed of faller points and the nip of the drafting rolls are, therefore, maintained under continuous contro1 throughout the length of the drafting Under preferred practice, the pins 63 in the faller bed I! are stepped up slightly in speed about 3%.;% to 5% over the linear speed of the belt 59. The drafting rolls 22 and 23 are driven at a speed greater than the travel of the faller pins which is predetermined to produce the desired degree of attenuation in the product sliver of the incident passage. The amount of draft and the number of doublings to be used depend upon the type of fiber handled and the characteristics desired in the yarn to be produced. Nevertheless, for the sake of illustration, numerical valuesofdrafts successfully employed in successive pin-drafting machines have been indicated in the schematic diagramof Fig. l. v

The normal intersecting types of gill boxused in the Bradford system have approximately a four-inch upper bed and a six-inch lower bed,

with 8.to 16 pins per inch measured cross-wise, the bed length being measured longitudinally. In carryingout my process, however, I employ pin drafters in which both the upper and lower beds 7 extend up to nine inches in the direction of stock travel and no ratch rolls are employed. At present, it is believed best results are ob tained by employing at least 22 pins per inch in the faller bars and as many as 29 pins per inch may be employed; A coarser pinning may be employed for coarser grades of stock. As indicated also in Fig. 1, the pin-drafting machines I2, I3 and l4 maybe successively more finely pinned. For a 64-grade wool, the best pinning is now believed to be 22 pins per inch in the pin six ends up and the third pin drafter H with five ends up and the fourth pin-drafter machin with four ends up. I I

The drafting heads, such as illustrated in Fig. 4, are mounted in two rows on either side of the spinning frame above banks of spindles 5| on either side of the frame in an arrangement similar to that customarily employed in conventional frames having roller drafting heads. Such spinning frames have two inclined-surface rails or supports running thelength of the frame on either side, one of which is represented in cross-section at 13 in Fig. 4. As indicated in Fig. 3, these spindles 5| are mounted in a bank below each row of drafting heads. Preferably the drafting heads are mounted in pairs or as twin units 14 as represented in Fig. 3. The aprons of each twin unit 14 have a'common power drive connection and are mounted so as to be removable in pairs as will be explained morein de tail hereinafter. 7 I

Each twin unit 14 has common feed rolls 3| and 32 and individual draft rolls 33 and 34 as indicated in Figs. 3 and 6. The feed rolls, which each unit Hfordriving allfour aprons, that is, :therear aprons 35 and the outside aprons 36 from the drive shaft "through a separate drive 114' a common drive shaft running the length of the spinningframe for allof the feed rolls 3| on one side of the frame and, likewise, a common "drive shaft 16 for all the draft rolls 33 on the same side of the frame. The aprons and 36, however, are'not directly driven from common :shaftsrrunnin'g the lengthof the frame. Instead etoifacilitateremovalof the apron mechanism in :twin units without necessitating the disassembly of the parts of the twin unit, an auxiliary apron driving shaft 11 is provided which runs the length of the spinning frame. Means are provided in g'ear IB'for each unit '14. It is to be understood that a suitable gear box 19 is provided for driving shafts 15, Hand "(including the'requ'isite change gears for changing roller speed ratios, if desired, and suitable mechanism, not shown, is "also provided for driving the spindle wharls 52 through bands, not shown, running at suitable speeds in relation to speeds of the shafts 15,

16 and 11. v As represented in Figs. '6 and 7, eachtw-in unit 14 has a separate supporting frame or casing including side pl'ates'BI. The side platesill include flanges 83by means of which they are removably mounted upon the front surfaces of uprights or brackets 84bo1ted to the lengthwise 86. The rear gear 89 in turn meshes with the drive ge'ar"'|8 carriedby the common apron drive 11.

In'order to drive the belts 35 and 36 without ten- "sion so asin effect to push the belts instead of pulling themes in an ordinary pulley'drive, squeeze rolls'9l and 92 are provided which are carried by hollowshafts 93'and Sljournaled in floating bearings 95, resiliently clamped together by a bolt 91 having a coil spring'98' mounted under a tension-adjusting nut 99'. The belts or aprons 35 and Marc compose'd of any suitable material such as leather or rubber impregnated and covered fabrics such asused in industrial rubber belting. Preferably, rubber belting is employed as suchi material may be obtained with ends bonded together without changing the thickness to formv endless belts. The belt material has sufficient resiliency so that it tends to take a form with the bends having the greatest'pos may also be called back or feed rollsor ratch rolls, include the power-driven rear or inside roll 3| and the freely running outside roll 32. Likewise, the drafting rolls 33 and 34, which may also be called delivery rolls or front rolls, include the power driven inside or rear roll 33 and the freely running friction-driven outside'roll 34. There is sible radius. Consequently, if mounted loose enough not to be under tension, as described, the belts will move with their inner confronting portions traveling toward and through the space between the guide bars 4| and 42 in response to .the driving action of the rolls and 86 and the and I04 respectively. The fixed shafts |0| to H34, inclusive, have square ends W5 to I08, respectively, as shown in Fig. 7. The shaft ends I05 and -|06 are eccentric with respect to the axes of the fixed supporting shafts and the'hollow shafts.

For receiving the square ends I05 to I08 inclusive, keyhole shaped slots I09 are provided in the side plates III of each twin unit 14. Each such keyhole slot I09 has a circular portion III of greater diameter than the diagonal dimension of the cross section of the square shaft end and has a parallel sided portion II2 sufficiently wide to make an easy slide fit with one of the square ends I65 to I08. Accordingly, the spacing between the confronting surfaces of the aprons 35 and 36 may be varied by rotating the eccentric square ends I05 or I06 to any of the four different possible positions, since this operation varies the spacing between the axes of the apron driving rolls 85 and 86. In this manner the space 31 between the confronting surfaces of the aprons 35 and 36 at their feed end may be varied in order to vary the softness of the control or to accommodate the apparatus to slivers of varying thickness in order to make sure that fiber control of the sliver is maintained without introducing any nip, and without applying any drag prior to reaching the snubbing bar 38. It will be observed that for any of these settings of the axes of the apron-supporting rollers, the spacing between the axes is greater than the sum of the radii of the rolls and the thickness of both aprons so that space remains between the confronting surfaces of the aprons at the feed or entry end thereof where the strand is received from the feed rolls 3I and 32.

Although the apparatus illustrated is especially useful in the drafting of worsted fibers, the inven tion is not limited thereto and may be employed also in'connection with other classes of fibers. It is well known to those skilled in the art that worsted and woolen fibers should not be drawn twice in the same direction. Accordingly interdraft is not ordinarily employed in the drafting of worsted or woolen fibers. However, some fibers such as cotton, for example, may successfully be drafted twice in the same direction and interdraft may be employed. The adjustable arrangement, described for varying the lateral spacing of the apron drive rolls 85 and 86, permits also providing a close nip at the upper or feed end of the aprons 35 and 36. Accordingly, the apparatus illustrated is adaptable for use, if desired, in connection with inter-draft of suitable fibers such as cotton fibers. In this manner very high draft ratios may be obtained by drafting successively from the ratch rolls 3I and 32 to the aprons 35 and 35 and again from the aprons 35 and 36 to the draft rolls 33 and 34 (Fig. 4).

In the drafting of worsted, however, the interdraft adjustment is not employed and I consider it important to maintain the spacing 31 at the feed end of the aprons 35 and 36. Consequently the effective length of ratch m the entire distance between the line of contact of the feed rolls 3I and 32 and the line of contact of the draft rolls 33 and.34. This length of ratch may be made longer than the length of the longest fibers in the strand 45 without at any time losing control of the shorter fibers and without failing to provide lateral compression of the strand to support the shorter fibers. The serpentine path, followed by the strand 45 after passing the snubbin bar 38, gives progressively increasing compression and lateral thrust upon the fibers. Since the aprons 35 and 36 are not maintained under tension, but are in elTect, pushed rather than pulled by the drive rolls 85 and 36 they are relatively loose and pass loosely over the guide bars 4| and 42 so that. even at the lower end of the aprons 35 and 36- the fibers are not gripped so tenaciously so as to result in rupture of the longer fibers of the draft caused by the grip of the draft rolls 33 and 34. The apron surfaces are held against the strand by the resilience of the apron so as to hold the strand softly like a glove. The serpentine path of the aprons 35 and 36, on either side of the snubbing bar 39, gives progressively increasing frictional drag to the strand bein drafted, to assure maintenance of all fibers in parallel condition.

In order that this frictional drag may be adjusted or that the snubbing effect of the snubbing bars 33 and 39 may be adjusted, these bars are also adjustably mounted. As illustrated in Fig. 6, notches II3 varying in depth are cut in the snub'bing bars 38 and 39 so that by varying the longitudinal position of the bars 38 and 39 in supporting slots I I4 and I I5 in the side plates BI, any desired adjustment may be obtained. Similar notches II6 of varying depth are provided in the top edges of the lower end apron guide rails 4| and 42 in order to permit requisite adjustment in case of slight variations in belt lengths or to vary the lateral compression effect at the lower end of the aprons 35 and 36.

To facilitate easy removal of the twin apron units as a unit, the supporting flanges 83 at the sides of the side plates III are also provided with button-hole or keyhole shaped slots III, cooperating with readily loosened screws II8 threaded into the vertical supporting brackets 84. Preferably thefian ges 83 carry locating pins I I9 cooperating with complementary sockets I2I in the vertical bracket surfaces 84.

The common apron drive shaft 11 is carried in a bearing block I22 having a slot I23 for receiving the shaft I1 and a cover I24 adapted to be screwed to the block I22 for closing the slot I23. Thus the shaft 1'! is readily removed.

Similar arrangements are provided for supporting the feed and draft r011 drive shafts I5 and 16, as shown in Fig. '7. There is a bearing block I25 bolted to the bracket 84 having a slot I26 for the drive shaft 16 with a securing plate I21. For carrying the feed roll drive shaft 15 there is a bearing block I28 bolted to the bracket 84 having a slot I29 for the shaft 15, adapted to be covered in this case by a second bearing block I3I having a slot I32 for receiving the supporting shaft I33 of the outer or friction driven feed roll 32. Although not clearly evident in the drawing owing to the scale employed, the slot I 32 is slightly inclined so that the shaft I33 in the roll 32 tends to roll downward and inward against the driven roll 3I. The friction driven draft roll 34 is also provided with supporting stub shafts I34 adapted to rest on an inclined edge I35 of a projecting portion of the lower bearing bracket I25. Feltcovered clearer rolls I36 and I3! may also be provided for removing lint from the surface of the draft rolls 33 and 34, respectively. The clearer roll I3! is shown as carried by stub shafts I38 riding on the same inclined surface I35 and the clearer roll I36 is mounted in a conventional linkage I39, illustrated in Fig. 4. If desired, a yoke I4I biased by a spring I42 under the adjusting nut I43 and a yoke-carrying pin I44 may be provided for releasing the draft roll 34 in response to a stop motion (not illustrated in Fig. 4) in the case of breakage of the sliver 45.

The bearing bracket I3I for carrying the friction driven feed roll 32 is interchangeable with a modified bearing bracket, illustrated in Fig. 11,

- for use when it is desired to incorporate a quick 17 acting automatic stop motion in an apron drafting head 14.

Preferably the strand 45 is supplied to the feed rolls 3| and 32 through a condenser I45 which is attached to a traverse rod I43, and may be of the trumpet type. The rod I46 isreciprocated a predetermined amount longitudinally of itself, that is cross-wise with respect to the direction of travel of the roving 45, by driving means at the end of the frame. Such driving means is known to those skilled in the art and is, therefore not shown. In this manner the condenser I45 serves to traverse the strand 45 widthwise of the drafting mechanism of Fig. 5 to distribute wearing action of the strand 45 on the parts to prevent concentrated wear of the control aprons 35 and 36, and of the feed and draft rolls 3|, 32, 33 and 34.

It will be noted that th lower edges of the lower guide rails 4| and 42 of the'aprons 35 and 36 are close to the nip of the drafting rolls or delivery rolls 33 and 34. The aprons extend substantially into the space bounded by the cylindrical surfaces of the drafting rolls 33 and 34 and an imaginary plane, not shown, tangent to both of these cylindrical surfaces. Such an imaginary plane would intersect the aprons 35 and 36. The drafting area extends from the nip of the feed rolls 3| and 32 to the nip of the delivery rolls or draft rolls 33 and 34. The actual extent of the drafting effect depends upon the length of the fibers in the roving 45. Each fiber, as it passes into the nip of the drafting rolls 33 and 34, is subjected to frictional resistance or retardation exerted by reason of lateral pressure or thrust by the opposed surfaces of the aprons 35 and 36.

Because of the close spacing between the nip of the drafting rolls 33 and 34 and the apron guide rails or bars 4| and 42, a relatively small percentage of fibers in the roving 45 is'so short as not to span the gap between theaprons and the nip of the drafting rolls. The short fibers which donot span the gap are carried along by the relatively high percentage of fibers in the strand which are long enough to span the gap. By this means the shorter fibers are maintained under fiber control as they travel across the gap. The result is negligible loss of fibers as fly waste, which evidences the more important result attained, of continuous fiber control being maintained on all the fibers of the roving 45 throughout the length of the drafting area.

The spacing between the opposed surfaces of the drafting aprons 35 and 36 is adjusted to produce the desired degree of tension on the fibers of the roving 45. The adjustment is made, as previously explained, by setting the eccentric shaft means I65 and I06 and the snubbing bars I I4 and H5 in order to provide the desired gradient of spacing between the apron surfaces longitudinally of the travel of the roving 45, and to provide the desired degree of snubbing action. The adjustment is made in accordance with the quality of the roving, the fibers which comprise the roving, and the count of yarn to be produced.

The shaft I5 is driven at a predetermined speed to drive the feed rolls 3| and 32 at a surface speed to travel the roving 45 at the desired predetermined speed of travel. The shaft 11 is driven at a predetermined speed to drive the aprons 35 and 35 at a surface speed sufiicient to receive the roving 45 as quickly as it is delivered by feedrolls 3| and 32. The preferred practice is to step up the linear speed of the aprons 35 and 36 slightly, up to for example, and this is accomplished in the gear ratio, of the inter-gearing between the shafts I5 and I1, such gearing being consolidated within a gear box I9. The increase in linear speed should not exceed the maximum recovery value of the stock, which is about 10% in most types of worsted stock, and may be as little as zero in some types of synthetic fibers, such as rayon. I

The shaft 16 is driven at such a speed as to drive the draft roll 33 with the required higher surface speed than the speed of travel of the aprons 35 and 36 and higher than the speed of travel of the strand 45 through the feed rolls 3| and 32 to produce the desired amount of attenuation of the roving 45.

According to one practice, the roving 45 which serves the spinning frame, can be the product strand of the last passage through pin drafting machines, such as illustrated in Fig. 2, the roving being fed to the spinning frame directly from the cans 28 in which it is received from the pindrafting machine. 'Underthis practice, there is no twist applied to the roving in any stage of the worsted process up to its being spun, and the product is a lofty yarn, having a texture similar to the product yarn of the French system.

Nevertheless, it does not follow that twisting the strand at some stage in theworsted process will invariably defeat the purpose of producing I a lofty yarn. A slight twist applied to the prod-- uct strand of one or more operations in the process will not detract from loftiness of the yarn to any noticeable or appreciable extent.

As already explained, if the last pin-drafting machine I4, indicated in Fig. 1, is of the spindle gill type, a twist of a fraction of a turn per inch, e. g., two-tenths turn per inch, may be employed and an additional twist of up to approximately. one and one-half turns per inch may be pro-:

The twist used in machine I4 is arranged to provide no twist and a .if, a cone rover is employed, the cone rover may beof the type employing apron drafting heads similar to those illustrated in Fig. 5, except that ordinarily in the cone rover it is more convenient to arrange the aprons with substantially horizontal confronting'surfaces and to arrange the feed rolls and draft rolls accordingly for substantially horizontal travel of the sliver before being delivered to the fiyers. In this case, the cone rover is supplied with sliver from rotating .cans instead of bobbins. As little twist may be imparted by rotation of the cans as desired, e. g. from one-tenth to five-tenths turns per inch.

Experiments determined that twists as low as,

0.5 turn per inch operatedsatisfactorily as supply ends in th spinning frame, the rovings withdrawing from the bobbins evenly, and without-1. drafting. Twists up to 1.0 turn per inch produced 1 yarn of the same loftiness and quality as comparable yarns spun from untwisted rovings. Higher degrees of twist up'to 1.50 turns per inch did notshow appreciable increased hardness in the product, and twists of 2.5 to 3 turns per inch, which are comparablewith' the practice of the prior art worstedprocess, produced a yarnof:

much greater loftiness, and finer quality, than yarn fabricated under the English system.

In a sliver or rovingwhich is entirely without,

twist, the fibers are arranged paralleland directed longitudinally of the strand. By twisting the strand, the fibers continue directed substantially longitudinally of the strand until a twist is applied of relatively high magnitude, for example, such as is applied under the prior art worsted process. A low degree of twist of the product strand of a passage in the worsted process will not operate to disarrange the fibers of the strand from disposition longitudinally of the strand, to any substantial extent.

It can be, therefore, stated as a general conclusion that loftiness and fine quality texture is attained in the product yarn of the process of the invention when the strand of fibers is maintained in throughout the several operations until the yarn is spun, and this statement applies in the case of the product strand of one or another passage being slightly twisted.

Although a stop motion may be provided to reduce lap waste, very few breakages occur and it is seldom necessary for the attendant to splice or lick in rovings.

Nevertheless, if desired, a stop motion may be embodied in the apron drafting apparatus, as illustrated in Figs. 11, 12 and 13. For this purpose the bearing block I3I, shown in Fig. '7 for supporting the free-running feed roll or outside feed roll 32, is replaced by a linkage for braking the feed roll 32 and lifting it away from the strand, in the event of breakage, in order to avoid delivery of further strand to the aprons 35 and 36. In addition, a delicately balanced switch carrying a guide eye, is provided at the lower end of the apron drafting head in order to actuate the feed roll braking and lifting means in response to breakage of the strand.

For supporting the linkage controlling the feed roll 32 and other associate mechanism, a frame I41 is mounted between each pair of uprights 84 carrying one of the twin drafting heads 14. The frame I41 comprises side arms I48 and a cross member I49. A center arm II is secured to the cross arm I49.

The side arms I48 and the center arm I5I have ears I52 in which are pivoted bell crank levers I53 with forwardly extending handles I54.for effecting manual resetting. Depending from the pivot points of the bell crank levers I53 are crank arms I55. At the lower end of each crank arm I55 there is pivoted a brake rigging I56. Each brake rigging comprises a brake bar I51 extending laterally to the rear of the peripheral surface of the free-running feed roll 32 with which it is associated. Each brake bar I51 is secured at the ends to a pair of curved links I58. Each curved link I58 is pivoted at the end opposite the attachment of the brake bar I51 to the lower end of the crank arm I55 at a pivot point I59. The links I58 are curved upwardly and have a concave under edge I6I adapted to ride over the stub shaft I33 of the feed roll 32. Small bearing blocks I82 screwed or otherwise secured to the forward end of the frame side arms I48 are provided for supporting the stub shafts I33.

Shelves I63 are provided at the angles of the side arms I48 and I49 and have openings I64 therein adapted to receive vertically slidable rods or bars I65 with a loose slide fit. There is a bell crank I53 and a brake bar I51 for each of the ratch rolls 32 and likewise a crank-operating bar I65 for each of the cranks I53. At the upper end, each crank-operating'bar I65 is pivoted to the rear end of one of the bell cranks I53, preferably by means of an elongated opening I66 (Figs. 11 and 12) in the bifurcated rear end porsubstantially untwisted condition tion I81, (Fig. 13) of the bell crank I53 and a cross pin I68 secured in the upper portion of the bar I65.

The lower end of each bar I65 has a collar I69 secured thereto. A compression spring I" is mounted between the collar I69 and the shelf I63 for depressing the bar I65 and drawing the crank arm I55 forward to break and release the feed rolls 32.

Each bar I65 has a socket or notch I12 therein adapted to cooperate with the nose or detent portion I13 of a pin I14 horizontally slidable in the shelf portion I63 of the frame I41. The detent I13 is spring biased by means not shown to engage the notch I12 in the bar I65 for holding the brake bar I51 out of the operating position until the detent I13 is retracted.

The frame I41 also has rear wings I15 supporting solenoids or electro-magnets I16 each of which has an armature I11, shown in Fig. 12 but omitted for clarity from Fig. 13. Each such armature I11 is pivotally joined to the end of the detent for retracting it from the notch I12 in response to energization of the solenoid I16. The solenoid I16 is adapted to be connected to a suitable source of energizing current I18 by means of leads I19 and I80.

For controlling the energization of the solenoid 16, a switch I8I is provided which may be of any suitable type adapted to carry a delicately balanced lever arm I82 and to close an electrical circuit in response to relatively minute variations in weight resting on the lever arm I82. A guide eye I83 is mounted in the end of the lever 282. The drafted sliver 48 from the draft rolls 33 and 34 is threaded through the guide eye I83 in such a manner that the weight of the sliver 48 normally holds the lever I82 in the open circuit position of the switch IBI, which is a socalled normally closed switch. The switch I6I may be of any suitable type responding to minute changes in pressure acting on the operating mechanism, such as switches of the type sold under the trade name of Microswitch, for example.

The Micro-switch I8I has contacts connected in series with the solenoid winding and the energizing leads I19 through a pair of conductors I84, and preferably also in series with a second switch comprising a stationary contact I85 and a movable contact I86. The stationary contact I85 comprises a button of conductor material, such as copper, mounted on the under side of the cross arm I49 of the frame I61, but insulated therefrom and connected through a conductor I81 to one terminal of the solenoid winding I16, the other terminal of which is connected to the current supply lead I19. For supporting the movable contact I86 an insulated bracket N38 is mounted upon the collar I69 at the lower end of the bell crank-operating bar :65. Preferably, the movable contact button I86 is carried at the end of a pin I89 slidably mounted in the bracket I88 and resiliently biased to the upward position by means of a compression coil spring IQI. The lower end'of the pin I89 is electrically connected to one of the leads I84 from the lvIicro-switch I81. The arrangement is such that the contact carrying pin I89 has considerable longitudinal play so that it is free to rise with respect to the supporting bracket I38 when the bell crank-operating bar I65 is in the lower or depressed position, as shown in Fig. 12, and is pressed toward the supporting bracket I88 when the bar I65 is in the upper or latched position represented in Fig. 11.,

When the spinning frame is to bestarted up after a shut down or after the solenoid I has operated, the operator depresses the reset handle I54 thereby releasing the feed roll 32 from the brake bar 51 and allowing the feed roll 32 to ride in contact with the driven feed roll 3|. This causes the feed rolls 31 and 32 to nip the strand 45 and causes the strand 55. to be fed through the aprons and 35 to the draft rolls 33 and 3%, from which the drafted strand it emerges. The oper ator passes the end through the guide eyes 183 and 54, the ring traveler 55 or cap or flyer and to the bobbin 53. Thereafter, as the sliver passes through the stop motion guide eye I83, the weight of the strand 48 is sufficient to hold the Microswitch I8! in an open circuit position. In depressing the reset handle I54, the operator will have caused the rod I55 to be lifted so as to permit the notch I12 therein to engage the detent 1Y3 which isthus permitted to enter the notch I12 and lock the rod I65 and the bellcrank lever I53 in the operating or drafting position of the drafting head. 4 In the event, however, that afdefective strand shouldbe supplied to the feedrolls 3| and 32 resulting in a break I 92 in theemerging strand 48, the switch-operating lever I82 will be returned to its normal position causing the closing of the switch I8I, which thereupon energizes the solenoid I16 since, as indicated in Fig. 11, the con tact buttons I85 and I85 are in contact when the bell crank lever I53 is in the drafting position.

22: speed with which the fibers are fed to the entry end of the drafting area, applying lateral pressure to the fibers and confining them between towardthe delivery end of the drafting area for increasing the magnitude of the lateral thrust by Upon energization of the solenoid I15, its armature I11 is drawn inward retracting the detent I13 from the notch I12 and permitting the rod I65 to move downward under the force of the spring I1l. 'Owing to the longitudinal, vertical play permitted the pin I89 carrying the movable contact button" I85, the electrical circuit between the contacts I35 and I86 is not broken until the rod I65 has moved downward sufficiently to assure the notch I12 being cleared by the pin IE3 and assure that the spring I1I will move the rod I65 fully to the downward position.

In this manner the brake bar I51 is first brought in contact with the surface of the feed roll 32, stopping the rotation thereof, immediately thereafter drawing the feed roll 32 away from the driven feed roll 3| so that the supply strand 45 is no longer nipped and no further strand is fed-through the drafting aprons 35 and 35. The opening of the contacts I85 and 186, as the rod I65 approaches its extreme downward position, serves to de-energize the solenoid I16 to avoid over-heating thereof, and to avoid closure of any electrical circuits while the apparatus is shut down.

Certain embodiments of the invention and certain methods of operation embraced therein have been shown and particularly described for the purpose of explaining the principle of operation of the invention and showing its application, but it will be obvious to those skilled in the art that many modifications and variations are possible, and it is intended therefore, to cover all such modifications and variations as fall within the scope of the invention which is defined in the appended claims.

What I claim is: I

1. In the art of fabricating worsted yarn and the like, the process which comprises drawing a batch of fibers in the form of a strand in a drafting area of predetermined length greater than the length of substantially any of the fibers in the batch, drawing the fibers at the delivery end of the drafting area at a multiple of the surface causing the confronting surfaces to converge from a spaced relationship to a substantially engaging relationship, whereby continuous fiber control is maintained without breaking the longest fibers or subjecting the strand to forces exceeding the elastic limit.

2. The art of fabricating worsted yarn or the like which comprises passinga batch of fibers in the form of a strand through drafting operations a predetermined number of times, in each of predetermined passages traveling the strand through a bed of faller points to a set of drafting rollers with a nip in close proximity to the faller point bed to control the fibers continuously throughout the length of the drafting area, and in another passage traveling the strand from feed rolls to front drafting rolls between opposed carrier aprons which extend from said feed rolls into closeproximity with the nip of the front drafting rolls, causing said aprons to converge and applying graduallyincreasing lateral pressure to the strand while between said carrier aprons for gradually increasing resistance to movement of the strand to control the fibers continuously throughout the drafting area from feed rolls to draft rolls.

3. The art of fabricating yarn or the like which comprises passing a batch of fibers in the form of a strand through drafting operations a predetermined number of times, in at least one of said passages drawing the strand through a bedof faller points moving in the direction of longitudinal movement of the strand, nipping the strand in close proximity to the exit end of the bed of faller points and simultaneously laterally compressing the strand to a fiat ribbon-like form,

folding in the edges of the ribbon-like strand and in another of the passages drawing the strand from feed rolls to drafting rolls while retarding the strand between converging flexible surfaces subjecting the strand to progressively increasing lateral thrust to control the fibers continuously throughout the drafting area from the feed rolls to the drafting rolls while gradually increasing the resistance to movement of the strand.

. 4. The art of fabricating yarn or the like which comprises passing a batch of fibers in the form of a strand through drafting operations a predetermined number of times, in at least one of said passages drawing the strand through a bed of faller points moving in the direction of longitudinal movement of the strand, nipping the strand in close proximity to the exit end of the bed of faller points, folding in the edges of the ribbonlike strand and in another of the passages drawing the strand from feed rolls to drafting rolls while retarding the strand between converging flexible surfaces subjecting the strand to progres sively increasing lateral thrust to control the fibers continuously throughout the drafting area from the feed rolls to the drafting rolls and in: creasing gradually the resistance to movement of the strand.

5. The art of fabricating worsted yarn or the like which comprises, blending different grades and qualities of fibers without regard for their staple lengths, passing a batch of the blend of fibers in the form of a strand through drafting operations a predetermined number of times, including doublings in predetermined passages to blend the fibers uniformly longitudinally and transversely of the yarn, during each passage maintaining fiber control continuously throughout the length of the drafting area by lateral thrust, in the last passage progressively increasing such lateral thrust, thereby gradually increasing resistance to movement of the strand, and spinning the product strand of the last passage.

6. The art of fabricating worsted yarn or the like which comprises, passing a batch of a blend of wool fibers comprising the product strand of a combing machine through drafting operations a predetermined number of times, including flbers other than wool in the first passage following the combing machine, including doublings in predetermined passages to blend the various fibers uniformly longitudinally and-transversely of the yarn, during each passage maintaining fiber control continuously throughout the length of the drafting area by lateral thrust, in the last passage progressively increasing such lateral thrust, thereby gradually increasing resistance to movement of the strand, and spinning the product strand of the last passage.

7. The method of attenuating astrand of fiber which comprises, travelling the strand longitudinally of itself in a drafting area from feed rolls along a path confined between surfaces into the nip of a-set of front drafting rollers, the confining surfaces applying lateral thrust to the-strand, causing the confining surfaces to approach each other more closely toward the delivery end and thereby progressively increasing the magnitude of lateral thrust applied by the opposed surfaces to the strand to increase gradually the resistance to movement thereof and maintaining such values of lateral thrust in successive portions of the drafting area as to produce retardation of the fibers of the strand to a predetermined-extent.

8. The method of attenuatinga strand of fiber which comprises confining the strand "between confronting surfaces the surfaces traveling between afeed end and an 'exit'end and 'beingsomewhat spaced at the feed end, causing said surfaces to travel in aserperitinep'ath, the surfaces approaching each other more clos'elythan'atth'e feed end, applying progressivelyincreasing lateral pressure to'thestrand of fiber and drawing'said strand between said surfaces from feed rollsat a longitudinal speed exceeding the speed of said surfaces by nipping the strand closely 'beyond the exit end of said moving surfaces.

9. The method of attenuating a strand of fiber which comprises causing a pair of surfaces to travel in confronting relation along a path having a feed end and an exit end and reverse around a relatively smalllradius 'to permit coming into close proximity to the nip of drafting rolls, causing said surfaces to converge 'toward each other along the path of confronting relationship, for applying increasing lateral pressure to the strand, and drawing the strand-of fibers through said surfaces from feed rolls while restraining the strand progressively during its passage between the surfaces and drawing it from the exit end with a close nip.

'10. The method of attenuating a strand of f1- bers which comprises passing the strand longitudinally between a pair of spaced longitudinally moving surfaces, causing the surfaces to con- H verge continuously along the path of travel of the strand, thereafter bending the surfaces in a serpentine path to apply lateral thrust to the fibers, and drawing the strand between the surfaces in the same longitudinal direction as the direction of travel of the surfaces.

11. The method of attenuating a strand of flbers which comprises passing the strand longitudinally from feed rolls between a pair of spaced longitudinally moving surfaces, causing the surfaces to converge along an extended path for snubbing the strand and applying progressively increasing lateral thrust to the fibers for control thereof by causing the strand to follow a varying path, and drawing the strand between the surfaces in the same longitudinal direction as the direction of travel of the surfaces.

12. Apparatus for attenuating strands of fibers which comprises a pair of feed rolls, a pair of draft roll and a pair of carrier aprons between said rolls extending substantially into the space bounded by the cylindrical surfaces of the draft rolls and an imaginary plane tangent to the draft rolls, said aprons having means for directing the aprons in serpentine paths in the portion of the aprons toward the draft rolls for snubbing the fibers, whereby continuous fiber control is maintained without subjecting the strand to forces exceeding the elastic limit, the confronting surfaces of the aprons near the feed rolls being spaced and converging in the direction toward the draft rolls.

13. Apparatus for attenuating strands of fibers which comprises a pair of feed rolls, a pair of draft rolls, a pair of carrier aprons between the said rolls extending in close proximity to the nip of the draft rolls,'a pair of drive rolls supporting said carrier aprons at the end thereof toward said feed rolls, a pair of guide strips supporting the carrier aprons at the opposite end in close proximity to the nip of the draft rolls, snubber bars for directing the carrier aprons in a serpentine path along their confronting surfaces located between said drive rolls and said guide strips, said drive rolls having their axes so spaced as to provide spacing between the confronting surfaces of the carrier aprons in the area between said drive rolls and the nearest snubber bar, squeeze rolls mounted laterally movable adjacent said drive rolls, and meansfor resiliently pressing said squeeze rolls toward said drive rolls for holding said carrier aprons against the surfaces of their supporting drive rolls, whereby the carrier aprons are driven with a pushing action instead of a pulling action, normally stationary spindles on which said drive rolls are revolvably mounted, said spindles having eccentric square ends, side plates for supporting the apron assembly having straight-sided openings to receive the square ends of said spindles, whereby the lateral spacing between said drive rolls and accordingly the spacing between confronting surfaces of the carrier aprons at the entry end may be adjusted by adjusting the angular mounting position of the drive roll supporting spindles in said side plates, and means for rotatively driving said drive rolls.

1 4. Apparatus for attenuating strands of fibers which comprises a pair of feed rolls, a pair of draft rolls, a pair of carrier aprons between the said roll extending in close proximity to the nip of the draft rolls, a pair of driverolls supporting said carrier aprons at the end thereof toward said feed rolls, a pair of guide strips supporting the carrier aprons at the opposite end in close prox-

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