US2196621A

US2196621A - Apparatus for treating textile fibers

Info

Publication number: US2196621A
Application number: US281508A
Authority: US
Inventors: Harold T Battin; Walter F Silva
Original assignee: United States Rubber Co
Current assignee: Uniroyal Inc
Priority date: 1939-06-28
Filing date: 1939-06-28
Publication date: 1940-04-09
Anticipated expiration: 1957-04-09

Description

April 9, 1940. H. T. BATTIN El AL APPARATUS FOR TREATING TEXTILE FIBERS s Sheets-Shet 1 Filed June 28, 1939 INVENTORS #46010 7.' 5477/ #441727) f. J71 144 ATTORNEYS April 9, 1940. H. T. BATTIN ET AL APPARATUS FOR TREATING TEXTILE FIBERS Filed June 28, 1939 5 Sheets-Sheet 2 INVENTORS 194K010 Z 8477/ W41 715/, E 671/4 ATTORNEY 6 April 9, 1940.

H. 1'. BATTIN ET AL APPARATUS FOR TREATING TEXTILE FIBERS 5 Sheets-Sheet 3 Filed June 28, 1939 I v 'INVENTORS BY W417? f7 5711 ATTORNE s April 9, 1940. H. 'r. BATTIN ET AL APPARATUS FOR TREATING TEXTILE FIBERS Filed June 28, 1939 5 Sheets-Sheet 4 INVENTORS 5645020 I 5477/ W4Zff/f r. 671/4 BY- PM ATTORNEYS V April 1940- H. T. BATTIN El AL 2,196,6

APPARATUS FOR TREATING TEXTILE FIBERS Filed June 28, 1959 5 Sheets-Sheet 5 INVENTORS h mmvw z 5477/ BY W41 75/? f. 5/11 4 M r W AT TORNE Patented Apr. 9, 1940 srrsnsrns roa rename 'rnx'rnn mans Harold '1. Battin, Ridgewood, N. .L, and Walter F. Silva, New York, N. Y., assignors to United States Rubber Company, New York, N. Y., a corporation of New Jersey Application June 28, 1939, Serial No. 281,508

19 Claims.

The present invention relates to novel apparatus for drafting and spinning textile fibers, and more particularly to reciprocating means for effecting the drafting operation. The invention may be employed to treat the usual animal and vegetable fibers and also the much shorter asbestos fibers.

It is well known that mule spun yarn is considerably softer than the usual ring and traveler spun yarn of the same size and number of twists per inch. but that mule spun yarn is more expensive to produce. The present invention contemplates an apparatus which is simple in construction and inexpensive to operate as compared with a mule spinning machine, while it is capable of producing yarn having the desirable soft characteristics of mule spun yarn. Furthermore, the apparatus of the present invention may be employed to draft much shorter fibers than those which can be satisfactorily drafted on the usual type of drafting mechanism employing sets of drafting rolls.

One feature of the present invention resides in means for advancing a strand or roving of loosely aggregated fibers and having associated therewith pairs of reciprocating drafting jaws adapted to attenuate or draft these fibers. The arrangement is such that the fibers are drafted by first one pair of jaws and then by the other and the jaws are so operated as to avoid subjecting the fibers to a severe jerk during the drafting operation.

Another feature resides in novel mechanism including eccentrics and cooperating eccentric arms for reciprocating these jaws and holding them closed during the drafting stroke and open during the return stroke.

Another feature resides in spinning means associated with said reciprocating drafting jaws and adapted to spin the yarn while the attenuated fibers are held first by one pair of jaws and then by the other pair.

Another feature resides in means for supin independent means for controlling: the opera ation of the drafting jaws. v Another feature resides in blast means for facilitating the passage of the strand or roving between the drafting jaws in threading up] the apif paratus, and which serves also to keep the operating parts free of dust and lint.

- in its. lowermost position, the yarn It is not fully understood why the apparatus of the present invention produces a yarn of much greater softness than the ordinary ring and traveler spinning mechanism, so that it resembles mule spun yarn in its feel. It is believed however that when the ordinary pairs of drafting rolls are used in connection with a ring and traveler spinning machine the fibers tend to cling to the surface 'ofthe rotating rolls and that these fibers are not twisted into the body of the yarn but tend to lie on the surface thereof and render the yarn harsh to the hand. In the present construction the drafted roving is firmly gripped by one pair of jaws or the other as the twist of the spinning mechanism is imparted thereto and this insures the proper spinning of all the fibers.

Still another feature of the invention resides in means whereby the drafted roving or strand may be applied to a rubber thread as a cover during the spinning operation to thereby produce a roving covered elastic yarn.

Other features of the invention and novel combination of parts in addition to the above will be hereinafter described in connection with the accompanying drawings which illustrate one good practical form thereof.

In the drawings:

Fig. 1 is a front elevation of one-drafting unit constructed to draft and spin simultaneously two rovings or strands;

Fig. 2 is a plan view of the mechanism of Fig. 1 with parts broken away and showing means for drafting one strand or roving at one side of the machine and another strand or roving at the opposite side of the machine;

Fig. 3 is a sectional view taken on the line 3-3 of Fig. 2;

Fig. 4 is a vertical sectional view taken on the line 4-4 of Fig. 1; a

Fig. 5 is a view of a detail feature showing the operation of the feed rolls and also thread guides;

Fig. 6 is a longitudinal sectional view through a gear casing to be described; I f

Fig. 7 is a detailview showing the upper pair and lower pair of drafting jaws, with their operating eccentrics set 180 apart and one eccentric in its uppermost position and the other eccentric.

s n means being also shown; I r I y I Fig. 8 is'a view similar to Fig. '7 showing the position of the jaws when the operating eccentrics are rotated clockwise through an angle of Fig. 9 is a similar view showing the position of shown as provided with one drafting apparatus f at one side thereof and another drafting apparatus at the other side thereof, it'is to be under-" stood that the unit may consist of only one drafting device, and that the entire drafting machine may be provided with a large number of drafting'units such as shown in Fig. 1 or of the single drafting units just referred to.

Referring now to the embodiment of the invention illustrated in the drawings, l0 designates a main casting adapted to support the feed means for delivering the roving or strand R of loosely aggregated fibers to the drafting jaws to be described. This feed means as illustrated comprises the feed rolls H and I2, and the casting I0 is shown as having one pair of these feed rolls disposed at one side thereof to feed one roving and another'pair of these feed rolls at the opposite side thereof to feed a second roving, as will be apparent from Fig. 1.

There is disposed at one side of the casting II, in the embodiment of the invention illustrated, a side casting l3 adapted to support the drafting jaws and operating means therefor for one of said rovings R, and there is disposed at the opposits side of this casting III a second and similar side casting l3 adapted to support the other set of drafting jaws and operating means therefor, as will be apparent from Fig. 1. The central casting l0 and side castings l3 are shown as secured by the bolts l4 to the supporting base I5.

It will be apparent, however, that a single casting' or supporting frame could be employed in place of the three castings just mentioned.

Each side casting i3 is provided at its uppe end with a forward bearing housing I6 and rearward bearing housing If, and within these housings, is rotatably mounted a shaft I8 adapted to operate the upper and lower pairs of drafting jaws to be described. The shaft I3 has mounted upon its rear end a driving wheel or pulley is which is shown as rotatably mounted on a reduced end portion 20 of the shaft l3 and is held against longitudinal movement thereupon by a collar 2|. It is desirable to pfivide clutch means whereby the shaft i3 may be placed in or out of driving engagement with the rotating pulley l3 and this is accomplished in the construction shown by providing, upon the inner face of the pulley IS the diametrically spaced lugs 22 each of which has rigidly secured thereto a spring plate 23 extending radially inwardly toward the shaft I8. These spring plates constitute one part of the clutch and the other part comprises the sleeve 24 slidably mounted upon the shaft l3 and connected thereto by the key 25. Upon the outer end of this sleeve are provided the oppositely disposed lugs 23. The sleeve 24 isjournaled within a bearing 21 mounted within the above mentioned housing l1, The arrangement is such that when the sleeve 24 is slid rearwardly so that its lugs 23 lie within the path of the springs 23 a yielding driving connection will be effected between the pulley I 3 and its supporting shaft l8, and when this sleeve 24 is moved to its forljecting rearwardly from the casting l3.

.end by a pin to the transversely extending shaft 3| which shaft is journaled in lugs 32 pro- This shaft 3! is supported for limited rocking and sliding movement by the lugs just mentioned and has secured to a projecting end thereof the operating lever 33. A coil spring 34 confined between one face of the arm 28 and lug 32 serves to urge the shaft 3| continuously in the direction of its length to thereby hold the handle 33 against one face of the casting l3 as shown at the right hand side of Fig. 1. When the parts are in this position the handle 33 rests upon a supporting lug 35 which serves to hold the handle raised in the shaft driving position. When it is desired to release the clutch and stop the rotation of the shaft it it is merely necessary to pull the shaft 3| longitudinally slightly against the pressure of the spring 34 so as to disengage this handle from the lug 3,5 and rock the handle 33 downwardly as shown at the left hand side of Fig. 1.

The shaft l8 at each side of the apparatus shown in Fig. 1 serves to operate the upper pair and lower pair of drafting jaws, and to this end it is provided at its forward end with two eccentrics disposed at an angle of 180 apart. In the construction shown the forward eccentric 33 secured upon a reduced portion of the shaft l3 serves to operate the lower eccentric arm 31 of Fig. 4, and the rearward eccentric 38 serves to operate the upper eccentric arm 33. These two eccentrics are non-rotatably secured to the operating shaft 13 by a pin 40, and washers 4i are provided to hold the eccentric arms 31 and 33 in operating relation with their corresponding eccentrics. The eccentrics and washers are shown as removably' secured in place upon the shaft i8 by the screw 42 which may be removed when desired to change the eccentrics shown for other eccentrics having a different throw to thereby vary the stroke imparted to the drafting jaws.

In accordance with the present invention the roving or strand R of loosely aggregated fibers ispulled forward from a source of supply, not shown, about a guide such as the pin 43 (see Fig. 3) and then downwardly between the nip of the feed rolls II and I2 which serve to deliver the roving to the drafting jaws. These jaws in accordance with the present invention comprise an upper pair and a lower pair and the operation is such that the upper pair grasp the strand at some distance from the nip of the feed rolls and move downwardly to partially attenuate the fibers, whereupon the second or lower pair of jaws grasps the strand adjacent the lowermost position of the upper jaws and move downwardly to further attenuate or draft the fibers.

In the embodiment of the invention shown, one upper jaw 44 and one lower jaw 45 is supported for sliding reciprocating movement along a vertical path, and to this end the upper jaw is rigidly secured to the head 46 and the lower jaw 45 is rigidly secured to the head 41. These two to the projection 48 formed upon the casting l8, and extend upwardly therefrom as clearly shown in Fig. 1.

The upper jaw 44 is provided with a cooperating jaw which is held in accurate alignment therewith and is supported for lateral movement relative thereto by the spaced pins 5| secured toand projecting laterally from the jaw 44. Likewise the lower jaw 45 is provided with the cooperating jaw 52 which is held in alignment therewith and supported for lateral movement relative thereto by the-pins 58.

The operation of these pairs of reciprocating drafting jaws is such that only one pair .of jaws acts upon the strand at a time, so that the first or upper pair of jaws partiauy effect the attenuating operation and then the second or lower pair of jaws grasps the fibers and completes the attenuating or drafting operation. Each pair of jaws is held closed during its downward or active stroke and open during its upward or inactive stroke, and simple mechanism of the present invention for operating these jaws in this manner at high speed includes the crank

arms

81 and 39 above described. The lower crank arm 81 is provided with an upwardly projecting tongue 54, and the upwardly extending arm 39 is provided with a downwardly projecting tongue 55. The upper end of the tongue 54 is pivotally secured to the sliding head 41 by the pivot pin 58, and the lower end of the tongue is pivotally secured to the sliding head 46 by the pivot pin 51.. 7

As a result of this construction the rotation of the eccentrics 36 and 38 actuates the

arms

81 and 39 so as to reciprocate the heads 41 and 46 respectively to thereby reciprocate the drafting jaws at a variable speed. The eccentrics serve also to tilt the arms 31 and 89 in first one direction and then another as will be apparent from Figs. 7 to 10 inclusive and this tilting movement is utilized to effect the'opening and closing of the

jaws

50 and 52 in the proper timed relation. The means for opening and closing the upper jaw 50 in the construction shown comprises the downwardly extending arm 58, see Fig, 1, the upper end of which is pivoted at 59 to the bifurcated portion of the lug or projection 68 provided upon the housing I6. The lower end of this arm 58 has the reduced portion 6| which projects slidably through a hole in the jaw 50. Rocking movement is imparted to the arm 58 to thereby open and close the jaw 56bythe connecting rod 62 one end of which-is pivotally secured to the arm 58 at 63 and a substantial portion of this rod is provided with a reduced diameter adapted to slidethrough a block 64 pivotally secured to the tongue 55. The arrangement is such that a coiled spring 65 mounted upon the reduced portion of the connecting rod .62 and confined between the block. and the nut 66 atthe outer end of this ;rod-,serves continuouslytb urge this rod in" a mentionedtprojection;-rl9t and the=upper' end of iarm; is; provided- Ewith i-a- "reducedportion which slides in a: holez formed in th'e jaw' Rocking movement iskimparte'd to the arm 81 -by a -.connect1ngfrod il whichhasa that slides within the block 68, and upon which reduced portion is provided a coil spring 10 similar to the construction just described for operating the upper jaw 50.

Having described the mechanism for operating the pairs of drafting jaws, we will now describe the means herein shown for driving the feed rolls II and I2 and for adjusting these feed rolls towards or from the drafting jaws to accommodate different length fibers to be drafted. The adjustment for drafting any particular roving or strand of loosely aggregated fibers should be such that the distance between the nip of the feed rolls anduppermost position of the. upper jaws is slightly greater than the length of the longest fibers.

In order to employ the drafting mechanism of the present invention to draft either short or .long fl-bers means is providedjwhereby the feed rolls may be'adjusted towards: or from the path of travel of the drafting -j'a .ws =-'T6 end in the construction shown,' the reanrol gil which is preferably a corrugated steelff .is power driven whereas the front jaw I! which isfrictionally driven is preferably provided with a. rubber cover. The pairs of rolls at the opposite sides of the central casting III are secured upon the opposite ends of the supporting shafts 1| and I2 which extend entirely through the gear casing 78. This casing rotatably supports these rolls and also supports them for swinging movement so that they may be adjusted towards the drafting mechanism. The gear casing 13 is mounted for rocking movement about the main driving shaft 14 disposed rearwardly of the operating jaws above described, and which shaft serves to positively drive the steel rolls II. The shaft 14 is rotatably supported by bearings I5 provided at the upper end of the central casting l0 and rotative movement is imparted from the power shafts 74 to the shaft II upon which the rolls II are mounted, by gears mounted within the casing 13. These gears comprise a main gear 18 rigidly secured to the shaft 14, an idler I1 supported by the shaft 18 and which idlerdrives the pinion 19 that is keyed to the shaft! I;

The front rolls I2 are frictionally driven from the-rear rolls l I and in accordance with the present invention means are provided whereby the front rolls l2 maybe moved frontwardly out of engagement with the rear rolls to thereby facilitate threading up of the machine and stop the feed of the roving. To this end the shaft 12 for the front rolls l2 passes through openings in the casing 13 of sumcient size to permit the desiredamount of swinging movement to be imparted to this shaft, and the means shown for supporting this shaft for swinging movement comprises the yoke 88, see Figs. 1, 3 and 5. This yoke straddles the housing 13 and is pivotally secured thereto bythe pivot pin 8|. The shaft 12 is journaled in the upwardly extendinglegs of this yoke at a point above the pivotpin 8| as will be apparent from Fig. 5. The rolls I 2 are normally held in feeding engagementQvvith the rear rolls? H by weight means comprisingth'e laterally extending pin 82 extending rearwardly from the lower'po'r- 'tion of the yoke and upon which pin is mount ed the weight which may be adjusted lengthwise of the pin to vary its effective weight. Means is providedfor holdingthe rolls i2 front? wardly away from their cooperating rolls l I. "To this 'end in the construction shown, the rocking handle is'provide'd. This'handle is pivotally secured by he pin eenth u wa d y P jecting lugs 86 provided upon the gear casing 18 and the arrangement is such that when this bandle is swung frontwardly from the raised position in which it is shown in Fig. 3, the projections 81 thereupon will engage the upwardly projecting fingers 88 of the yoke 88 and swing the free end of this yoke frontwardly to thereby separate "therolls II and I2.

It will be seen from the foregoing that the feeding rolls II and I2 are supported by the gear casing I3 for movement in the arc of a circle about the drive shaft H towards and from the path of the drafting jaws and that the rolls I2 are also' supported for movement horizontally toward and from the rolls II. In order to adjust these feed rolls towards or from said jaws and to lock them in any desired position, the adjusting screws 88 and 88 are provided. The upper. adjusting screw 88 has threaded engagement with a laterally extending portion of the gear casing I8 and is arranged so that the lower end of this bolt may abut against a projection upon one housing 15 for the shaft ll, whereas the upwardly extending bolt 98 is threaded in the projection 8i upon the gear casing I3 and the upper end of this bolt abuts against a projection upon the other housing I5 as will be apparent from Fig. 3. It will be apparent that by backing off one of these bolts and tightening the other the desired vertical adjustment of the feed rolls II and I2 may be secured.

Various means may be provided for driving the power shaft H and the operating pulleys I! one of which is provided at the right hand side of the central casting I8 and the other at the left hand side thereof as shown in Fig. 2. I'he pulleys I9 for operating the drafting units shown in Fig. 1, or any desired number of such drafting units, may be driven by means of an endless belt 82 which may be driven by any suitable means such as a motor 93, see Fig. 11, and if this is a variable speed motor it may be employed to drive these pulleys. I9 at different speeds. I

It is desirable to provide means for driving the power shaft I4 at different speeds because the degree to which the fibers forming the strand or roving R are drafted may be controlled by increasing or decreasing the speed of the feed rolls II and I2. If these rolls are operated slowly while the drafting jaws are operating at high speed a high draft will be secured, and the amount of draft imparted to these fibers will. be decreased as the speed of the feed rolls II and I2 is increased.

Therefore the means shown in Fig. 11 for di i ing this shaft I4 at any desired speed comprises a motor 84 which may be operated by the Reeves or other type of variable speed driving mechanism 95. This variable speed mechanism by means of a chain 96 and cooperating sprockets operates reducing gears, not shown, within the gear casing 91 to thereby drive the shaft I4.

By referring to Figs. 7 to 10 inclusive, the operation of the upper and lower pairs of drafting jaws will be clearly understood. As above stated the operating eccentrics 36 and 38 have the enlarged portions thereof disposed at apart to thereby cause one pair of jaws to effect its drafting operation while the other pair of jaws is being moved in the non-drafting direction to the initial drafting position. By referring to Fig. 7 it will be seen that both pairs of jaws are closed, as the lower jaw has just completed its drafting operation whereas the upper jaw is ready to start its drafting operation. By referring to Fig. 8

in which the eccentrics have advanced through an angle of 90", it will be seen that the upper jaws are moving downwardly as indicated by the arrow andhave partially completed their attenuating operation, whereas the lower jaws at this instant are in their open position and are being moved upwardly as indicated by the arrow towards the upper end of their path of travel.

In Fig. 9 in which the eccentrics have advanced through an angle of 180 from their position in Fig. I, it will be noted that the upper jaws are at the lower end of their stroke and the lower jaws are at the upper end of their stroke so that these two pairs of jaws lie close together. At this instant the'upper jaws are beginning to release the strand as the lower jaws grip it. By referring to Fig. 18in which the eccentrics have rotated through 270 from their position in Fig. 7 it will be noted that the lower jaws are closed and are moving downwardly on their attenuating'stroke whereas the upper jaws are'open and are moving upwardly as indicated by the arrows.

The operation of these jaws is such that the strand being drafted is always gripped by at least one pair of jaws and the drafting operation is invention may be employed to attenuate or draft fibers irrespective of whether or not the fibers are twisted immediately thereafter, means is shown in Fig. 7 for twisting or spinning the drafted fibers to thereby produce'the yarn Y. This means as shown comprises the usual ring 88 and traveller 88 adapted to cooperate with the rapidly rotatingtake-up package I88 which may be driven by the whirl I8I and belt I82. As the yarn Y passes downwardly from the drafting jaws it passes through the usual pigtail I83 disposed in spaced relation to the upper end of the package I". I

It is found in practice, that the feed rolls II and I2 may be much smaller in diameter than the ordinary roving drafting rolls. Furthermore, by employing the reciprocating drafting jaws of the present invention, the upper jaws may be brought much closer to the nip of the feed rolls than the distance usually provided between the first and second pairs of drafting rolls of the ordinary drafting mechanism. Therefore, the present device is adapted to draft muchshorter fibers than can be drafted by the usual drafting rolls. Furthermore, by employing the construction of the present invention whereby the strand being drafted is always gripped by at least one pair ofreciprocating jaws, the'twist imparted to the yarn Y is prevented from passing upwardly beyond the upper pair of jaws so that it never reaches the nip of the feed rolls. This insures the proper spinning of all the fibers and produces a yam having the soft feel or hand characteristic of mule spun yarn.

. In order to help keep the jaws clean and free of lint and to facilitate their operation and the threading up of the machine, it may be desirable to provide means for producing a very slight air blast between the upper and lower pairs of jaws. This may be accomplished by providing an air pipe I such as shown in Fig. 1 having the 7s laterally extending nozzle I04 positioned to direct a slight blast of air continuously between the pairs of jaws. This clears the top of the lower pair of jaws when they are closed and causes some air to pass vertically between the jaws when they areaopen to remove the lint. It

' also appears to help the fibers to pass down bethat the bare rubber thread T may be led downwardly from any suitable source of supply (not shown) about a guide I05 and then laterally to the guide I06 placed just below the nip of the rolls II and I2 so that this rubber thread may 'pass downwardly with the fibers being drafted.

The elasticity of this rubber thread accommodates the attenuating action of the drafting jaws thereupon, and the twist imparted to the drafted strands and rubber core by the spinning mechanism will serve to wind or twist the fibers about;

the rubber core as a cover to thereby produce the elastic yarn E consisting of a rubber corehaving a single roving like cover spun or wrapped thereupon.

The operation of the machine may be started as follows: The shaft 14 is operated at the desired speed by starting the motor 94 and adjusting the variable speed device 95 to operate the feed rolls II at the proper speed. The spinning mechanism shown in Fig. '7 is driven from any suitable source of power by the belt I02, and the pulleys H! as above stated and driven from the motor 93 by the belt 92.

When the operator is ready to thread up a roving R he raisesthe lever 84 to permit the rolls l2to move toward the rolls ll under the action of the weight 83' and thereby grip and feed this roving. The operation of the drafting jaws may then be started by raising the lever 33 to rest upon the lug 35 as shown to the right in Fig. 1. It should be noted that the roving may be introduced between these jaws by .moving it horizontally therebetween- The drafting jaws are operated by their eccentrics at a variable speed that is relatively slow at each end of the stroke and highat the central portion of the stroke. This slow initial stroke movement prevents the fibers from being jerked at the instant they are engaged by the jaws, as is the case when the usual drafting rolls are used, and thereby lessens the strain upon the individual fibers. The down stroke of the jaws during the major portion of their travel is sufficiently faster than the feed of the roving to cause the roving to be attenuated first by one pair of jaws and then by the other.

It will be apparent from the foregoing that the reciprocating drafting jaws of the present invention can be operated at high speed. It is found in practice that theoutput of the present device is approximately as high as that of the ordinary series of drafting rolls but that the resulting yarn is much softer.

Having thus described our invention, what we claim and desire to protect by Letters Patent is:

1. A textile fiber drafting mechanism, comprising a pair of feed rolls having a nip for advancing a strand of loosely aggregated fibers, two pairs of reciprocating drafting jaws operable upon the strand so that one pair at a time grips the strand and attenuates it by pulling it forward relative to said nip, and means for rotating the feed rolls and reciprocating said jaws.

2. A textile fiber drafting mechanism, comprising a pair of feed rolls having a nip for advancing a strand of loosely aggregated fibers at uniform speed, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said nip, whereby one pair of jaws completes its attenuating operation as the second pair starts its attenuating operation, and means for rotating the feed rolls and reciprocating said jaws.

3. A textile fiber drafting mechanism, comprising a pair of feed rolls having a nip for advancing a strand of loosely aggregated fibers at uniform speed, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said nip, whereby the first pair of jaws .partially attenuates the strand and the second pair completes the drafting operation, and means for rotating the feed rolls and reciprocating said-jaws.

4. A textile fiber drafting mechanism, comprising a pair of feed rolls having a nip for advancing a strand of loosely aggregated fibers, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said nip and thenrelease the strand, and means for rotating the feed rolls and reciprocating said jaws to draft the strand.

5. A textile fiber drafting mechanism, comprising a pair of feed rolls having a nip for advancing a strand of loosely aggregated fibers, two pairs of reciprocating drafting jaws operable one pair at a time and along difierent paths to grip the strand and attenuate it relative to said nip and then release the strand, and means for rotating the feed rolls and reciprocating said jaws to draft the strand.

6. A textile fiber drafting mechanism, comprising feed'means for advancing a strand of loosely aggregated fibers, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to cating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said feed means and then release the strand,

' means for actuating said jaws, and means for twisting the drafted strand.

8. A textile fiber drafting mechanism, comprising a pair of feed rolls having a nip for advancing a strand of loosely aggregated fibers, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said nip and then release the strand, means for rotating the feed rolls and reciprocating said jaws to draft the fibers, means for twisting the drafted fibers, and said strand being at-all times gripped by at least one pair of said jaws to prevent the twist from reaching the nip point.

9. A textile fiber drafting mechanism, comprising a pair of feed rolls having a nip for advancing a strand of loosely aggregated fibers, means for operating said rolls, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said nip, and means for operating said jaws to reciprocate them and hold them closed during their working stroke and open during their return stroke.

10. A textile fiber drafting mechanism, comprising a pair of feed rolls having a nip for advancing a strand of loosely aggregated fibers, means for rotating said rolls at a constant speed, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said nip, and means for reciprocating said jaws so that they travel faster than the feed of said strand during a part of each working stroke and slower during a part of said stroke.

11. A textile fiber drafting mechanism, comprising a pair of feed rolls having a nip for advancing a strand of loosely aggregated fibers. means for rotating said rolls, two pairs of reciprocating drafting jaws operable to grip the strand and attenuate it relative to said nip,.and operating means for said jaws comprising a power driven shaft having angularly disposed eccentrics thereupon one for operating one pair of jaws and the other for operating the other pair of jaws, an eccentric arm for each eccentric, one of said arms being connected to one pair of jaws and the other to the other pair of jaws for rocking movement relative to its eccentric and jaw.

12. A textile fiber drafting mechanism, com-' prising feed means for advancing a strand of loosely aggregated fibers, a pair of reciprocating drafting jaws operable to grip the strand and attenuate it relative to said feed means, and operating means for reciprocating said jaws and moving them into and out of gripping engagement with said strand, comprising a power driven eccentric, an eccentric arm pivotally connected to one of said jaws and adapted to be rocked about said pivot by said eccentric to thereby open and close and reciprocate said jaws.

13. A textile fiber drafting mechanism, comprising feed means for advancing a strand of loosely aggregated fibers, a pair of reciprocating drafting jaws operable to grip the strand and attenuate it relative to said feed means, and operating means for reciprocating said jaws and moving them into and out of gripping engagement with said strand, comprising means forming a slide-way for guiding the reciprocating movement of one jaw, an eccentric arm pivotally connected to said jaw and adapted to be rocked about said pivot by said eccentric to thereby reciprocate said jaw and also efiect the opening and closing of the other jaw.

14. A textile fiber drafting mechanism comprising feed means for advancing a strand of loosely aggregated fibers, two pairs of reciprocating drafting jaws operable to grip the strand and attenuate it relative to said feed means, a slide-way for supporting one jaw of each pair for reciprocating movement, a power driven eccentric for operating each pair of jaws, an eccentric arm pivotally secured to 'each of said sliding jaws and operated by an eccentric, and means for utilizing the movement of said arm by its eccentric to eflect the opening and closing of the jaws.

15. A textile fiber drafting mechanism, comprising ieed rolls for advancing a strand of loosely aggregated fibers, two pairs of reciprocating.

drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said rolls, means for driving said rolls and actuating said jaws, and means for supporting said rolls for adjustment towards and from said jaws to accommodate diil'erent length fibers.

16. A textile fiber drafting mechanism, comprising feed rolls for advancing a strand of loosely aggregated fibers, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said rolls, means for driving said rolls and actuating said jaws, and means for supporting one of said rolls for movement toward and from the other to start or stop the feeding of said strand.

17. A textile fiber drafting mechanism, comprising feed rolls for advancing a strand of loosely aggregated fibers, two pairs of reciprocating drafting jaws operable to grip the strand and attenuate it relative to said rolls, means for driving said rolls and actuating said jaws, manually controlled means for starting or stopping the feeding of said strand by said rolls, and independent manually controlled means for starting and stopping the operation of said jaws.

18. A textile fiber drafting mechanism, comprising feed means for advancing a strand of loosely a gregated fibers, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said feed means, mechanism for actuating said feed means and said jaws, and means for directing an air blast between said jaws to thereby facilitate the keeping of said jaws clean and free of lint.

19. A machine for making elastic yarn, comprising feed rolls for advancing a strand of loosely aggregated fibers, two pairs of reciprocating drafting jaws operable one pair at a time to grip the strand and attenuate it relative to said feed rolls, means for actuating said jaws and rolls, means for supplying an elastic thread to a point adjacent said rolls and then between said jaws, and means for twisting the thread and drafted fibers as they are held by one pair of said jaws to wrap the fibers about the thread as a cover.

HAROLD T. BATTIN. WALTER F. SILVA.