US2522332A

US2522332A - Textile drafting apparatus

Info

Publication number: US2522332A
Application number: US612483A
Authority: US
Inventors: Edward J Abbott
Original assignee: Abbott Machine Co Inc
Current assignee: Abbott Machine Co Inc
Priority date: 1945-08-24
Filing date: 1945-08-24
Publication date: 1950-09-12
Anticipated expiration: 1967-09-12
Also published as: FR926018A

Description

Sept. l2, 1950 AE. J. ABBoTr 2,522,332

TEXTILE DRAFTING APPARATUS Filed Aug. 24, 1945 3 Sheets-Sheet 5 j? l f wenn J- a az- 1 QU.

Iwana'r' n Petented Sept. l2, 1950 UNITED STATES PATENT -orrlce TEXTILE DRAFTIN G APPARATUS Edward J, Abbott, Wilton, N. n., assignmto Abbott Machine Company, Wilton, N. H., scorporation of New Hampshire Application August, 1945, Serial No. 612,483

18 Claims. (Cl. 19-130) This invention relates to textile drafting apparatus, and has for one of its principal objects to provide apparatus capable of increasing the degree of draft consistently with securing evenness of the resulting drafted product. The invention is applicable to the various stages of textile manufacture that involve drafting, for instance, the stages in which machines referred to as slubbing frames, roving frames or spinning frames are employed. In this application the therm sliver is used in a generic sense to refer to a textile strand adapted to be drafted, that is, a textile strand of which the fibers can slide with relation to each other, the strand not having acquired sufficient permanent twist to prevent such action. Thus, as here used, the term sliver includes the sliver initially produced for example by carding and also includes the draftable material which at subsequent stages is referred to as slubbing and roving. As will be evident from the above, the term "drafting" is here used to refer to elongating a sliver by causing its bers to slide with relation to each other.

In drafting textile materials, particularly as the degree of draft is increased, there is the problem of exercising sufficient restraint on the material to prevent the shorter fibers from becoming bunched in the drafted product. Twist applied to the material before a drafting step, for instance at the conclusion of a preceding drafting step, is a factor tending to restrainthe short bers. However, as the degree of drafting is increased, the amount of twist, considered as turns per unit of length left in the material as it reaches the front drafting elements, becomes correspondingly less, so that previously-applied twist eventually becomes so slight asto be ineffective in controlling the shorter fibers.

Accordingly, in certain machines employing a high degree of draft, intermediate carrier rolls or aprons are provided in order to confine and restrainthe fibers, rolls or aprons being employed because they provide moving surfaces that insure a definite forward movement of all of the bers.

It is usually desirable to extend such intermediate rolls or aprons as close as possible to other elements of the drafting apparatus. For instance in the case of intermediate rolls or aprons located between two sets of drafting rolls or similar elements, it is often desirable for these intermediate rolls or aprons to extend close to the drafting rolls or similar aprons which precede the intermediate rolls or aprons, and even more close, if possible, to the drafting rolls or similar elements which follow. Yet practical 2 I considerations limit the closeness with which carrier rolls or aprons can be made to approach other usual drafting elements. Reduction in diameter of intermediate carrier rolls aids to some extent in getting them nearer to other drafting elements, but the point is soon reached where the carrier rolls, because of their small diameter. have too great a tendency to wrap the fibers up upon them, forming what are termed bungs or laps A similar limitation exists in the case of intermediate carrier aprons, because it is undesirable for aprons to beI bent abruptly around rolls of too small a diameter.

Consequently, in usual forms of drafting ma.- chinery, there has had to be a substantial gap between the carrier rolls or aprons and drafting rolls or similar elements. The sliver has had to pass across this gap unconned, and this has constituted an obstacle to attempts to increase the degree of drafting that could be employed in practice.

The present invention overcomes this limitation and provides for transferring the sliver from one element whosesurface moves with the material to another element whose surface moves with the material, with very little unconflned travel of the sliver between such successive surfaces.

In the illustrated apparatus one of the elements of the apparatus is a rotatable member presenting a rotating end surface to the sliver. For yieldingly urging the sliver against this rotating end surface, a further rotatable member may be yieldingly opposed to the first rotatable member so that opposed end surfaces of two rotatable members engage the sliver therebetween.

Further objects and advantages of the invention will be apparent from this specification and its drawings wherein the invention is explained by illustration and description of a preferred example thereof.

In the drawings Fig. 1 is aview, taken on the plane I-l of Fig. 2, of a preferred form of drafting apparatus according to the present invention shown by way of example as embodied in a spinning machine;

Iig. 2 is a vertical sectional view of the device of Fig. 1; and

Fig. 3 is a diagrammatic view from the point of View of Fig. 1 but three times enlarged, showing the action of the apparatus of Fig. 1 on a typical roving used in cotton manufacture.

The invention may be embodied in a variety of constructions in which the end surface of a rotatable member'either receives the sliver after the latter has been discharged from some preceding drafting elements such as a pair of back drafting rolls or aprons, or delivers the sliver to some following drafting elements such as a pair of front drafting-rolls or aprons, or does both ofthese things for instance as in the machine of the drawings of this application. In this application the term drafting elements", is not limited to the forward elements that pull the sliver forward but is intended to be broad enough to include also rolls, aprons or the like that exert a .holding action on the sliver, resisting such forward pull.

For simplicity of illustration the invention is shown as embodied in drafting apparatus of a simple type which employs usual upper and lower fn/t rolls Ill-and II and usual upper and lower back rolls I2 and I3 respectively, the fron't and back lower rolls being driven positively at speeds which establish the desired degree of drafting of the sliver between these rolls.l This degree of drafting may be relatively high in this stage. or in cases where the rolls Iii, l I and I2, I3 form part of a coordinated larger system of drafting apparatus there may be cumulative drafts before and after the illustrated sets of rolls and, if desired, little or no draft between these rolls. The spacing between these pairs o f rolls I0, II and I2, I3 may be varied depending upon the fibers treated, the stage of manufacture of the material, the type of drafting system employed and upon whether or not the equipment'such as illustrated is used alone or as part of a larger system of drafting apparatus. v

The front and back upper rolls may be loaded as usual by a saddle I5 pulled downwardly hv a stirrup IB and weighted lever I'l. Usual trumpet guides I9 may be employed to guide the entering -sliver in between the back rolls I2 and I3, and usual pigtails 26 may be employed to receive the drafted strands as they pass to the usual twisting and winding mechanism of the spinning frame. In Fig. l, two slivers are shown as passing through adjacent sets of rolls as shown by the dotted lines S-S.

Thus the machine to which the invention is shown as applied involves discharge of the sliver from` between arcuately moving surfaces of one set of drafting elements and reception of thel rolls, the invention is equally applicable in case any one or more of these arcuately moving surfaces is the surface of a belt or apron. Thus the arcuately moving surfaces of the front elements.

As mentioned above the invention involves provision in the apparatus of a rotatable member presenting a rotating end surface to the sliver being drafted. The drawings show such element as a rotatable disk 2i of which the substantially flat upper surface engages. the sliver in between the front and back` drafting elements. This substantially flat upper surface of the disk 25, constituting an end surface of a. rotatable member, preferably lies approximately in a plane which is parallel to a line of contact of the front draft rolls with the sliver and also' parallel to a line of contact of the back draft rolls with the sliver, such plane in which the surface of disk 2l lies preferably being coincident with both of these lines of contact. 'Ihe sliver is .pressed against this rotating surface by suitable means, preferably, as shown, by another cooperating rotatable disk 28. l i

While certain of ,the advantages of the invention can be secured by mounting the two such disks one directly over the other, improved results are obtained if the axes of the disks are olfset laterally of the path of the sliver, as shown in Fig. l, so that the two disks overlap only in part but overlap substantially throughout the zone in which they act on the sliver.

As a mounting for the disks 23 and 26, a yoke 30 (Fig. 2) may be provided, equipped with upstanding pins 3| and 32 upon which the disks rotate. The upper surface of the yoke 30 also constitutes a supporting surface upon which the lower disk 25 is held. The weight of the upper disk yieldingly urges the upper disk against the sliver and yieldingly presses the sliver against the lower disk.

The sliver-engaging surface of one or both of the disks maybe given a slight concavity which has the effect of improving the evenness with which the two disks bear upon a somewhat tapering sliver.

It is preferred to provide for driving each of the disks so that its portion which engages the sliver rotates generally in the direction of progress of the sliver. Thus as viewed in Fig. 1 the y lower disk 25 is driven counterclockwise and the sliver could be delivered from cooperating aprons v Whose surfaces move in arcuate paths as they discharge the sliver at the back of the apparatus, and the sliver could be received by cooperating aprons whose surfaces move in arcuate paths to grip the sliver at the front of the apparatus. In any of these cases the sliver-engaging surfaces of the back elements, whether they be rolls or aprons, have at least a line of contact with the upper disk 26 is driven clockwise as indicated by the `arrows thereon. A positively driven shaft 3d is shown as extending through the yoke 30 parallel with the front and back draft rolls and beneath the disks. Shaft 34 carries collars 35 and 33 which respectively engage the

disks

25 and 26. lreferably the lower disk 25 is driven positively by pins 38 in thecollar 35 engaging in recesses 39 in the lower face of this disk, and the upper disk 26 is driven by contact with its cooperating collar 35.

Where the trumpets I8 are. as usual, reciproaccordingly and equalize wear on the rolls, 'the whole assemblage of the shaft 34, yoke 30, and

sliver and leave the sliver in arcuate paths as they The invention in one aspect is concerned with confining the sliver in between the time it is released by the arcuately moving surfaces of the back elements and the time it isreceived by 'the

disks

26 and 26 may also be reciprocated longitudinally of the rolls in synchronlsm with the trumpets I9 so as to preserve substantially the `relative positions of the overlapping disks and of the sliver as the sliver is shifted back and forth by the trumpets.

The force with which the sliver is pressed against the end surface of the rotating member, such as a disk 2B, may of course be varied in accordance with the extent to which it is desired that the sliver be gripped at this place. As shown in combination with both the front rolls I0 and I I :,saassa and the back rolls I2 and I8, only a relatively light pressure of the disks Il and il upon the sliver is desired and the weight of the relatively light upper disk can accordingly be yrelied upon to urge this disk 2l yieldingly against the sliver.

-When heavier pressure is desired, the upper disk can be made heavier or otherwise loaded as by 'springs or weights so as to press harder against the sliver. Any degree of grip, including a practically positive grip upon the sliver, can thus be secured. A positive grip upon the sliver is de- `the end surface ofthe rotating member engages the sliver between two sets of positively-gripping mechanism,- as illustrated.

In general, when the disks are located between a set of front draft rolls and a set of back rolls and the disks engage the sliver relatively lightly, I prefer to drive the disks at speeds which tend only slightly to accelerate the sliver reaching the disks, and to drive the front draft rolls at speeds which produce a relatively high degree of draft between them and the back rolls. However the invention is applicablev to situations -in which there is little or no draft between the set of rolls that precedes and the set of rolls that follows the disks. Using the disks in commotion with a set of front draft rolls, without any back draft rolls, or in conjunction with a set of back draft rolls, without any front draft rolls, the relative speeds of the disks and the cooperating set of draft rolls may be adjusted to give a relatively high degree of draft.

The original patent drawings forming part of this application show the apparatus in full size in Figs. l and 2 and three times full size in Fig. 3, as adapted to a cotton spinning machine. In use of the invention in drafting cotton il-bers, as well as in application of the invention to the Bradford worsted system, close proximity of the sliver-engaging portions of the rotating faces of the disks to both a set of drafting elements in rear of the disks and a set of drafting elements in front of the disks is desirable, but is of more importance with respect to the drafting elements in front ofthe disks because of the high degree of draft taking place adjacent to the front drafting elements. is rendered possibleby the invention.

Thus as shown in the drawings both disks 25 and 2l are shown as extending well in between the arcuately moving surfaces of both the front drafting elements and the back drafting elements. As shown in Fig. 1, overlapping portions of the disks extend substantially to, and may even extend into, the space defined by orthogonal projection of the arcuate path of a front drafting element upon the path of the sliver, and also the space defined by orthogonal projection of the arcuate path of a back drafting element uponthe path of the sliver. The sliver is confined between the moving surfaces of the disks almost immediately after discharge from thearcuately moving surfaces of the drafting elements I2, I3 and this confinement is maintained up to a very short distance from the point of engagement of the sliver by the arcuately moving surfaces of the drafting elements I Ii, I I.

A very close relation of these parts cal woolen'system of drafting, in which the front draft rolls are one to two feet distant from 'the back draft rolls, to provide a relatively long space in which drafting of relatively unrestrained sliver can take place, the disks 25, Il can more advantageously be disposed relatively close to the front rolls rather than close to the back rolls.

The principle of engaging the sliver between end surfaces of oppositely rotating members may advantageously be employed to impose on the sliver a different condition as to twist than the sliver would otherwise have.

As mentioned above, each of the disks is preferably driven so that its portion which engages the sliver rotates generally in the direction of progress of the sliver. Thus the cooperating surface portions of disk 25 and disk 26 have components of motion along the line S-fs (Fig. l) so that these surface portions advance generally with the sliver although not necessarily at the same speed. The forward component of the surface motion of the disks insures that substantially all of the material of the sliver, including short fibers, will be fed forward and partake of the general advance of the sliver as a whole.

In the initial part of the region in which the sliver is engaged between the disks, the surface portion of disk 25 which engages the sliver from below has a component of motion toward the left, and the opposed surface portion of disk 26 which engages the sliver from above has a component of motion toward the right, these oppositeiy-directed components both being transverse to the direction of advance of the sliver. Consequently, the

'sliver in the initial region of confinement is acted vrolls III, II toward the disks).

Then, farther along in the latter part of the region in which the sliver is engaged between the disks, the surface portion of disk 25 which engages thesliver from below has a component of motion toward the right, and the opposed surface portion of disk 25 which engages the sliver from above has a component of motion toward the left, these oppositely-directed components again beingtransverse to the direction of advance of the sliver. As a consequence, the sliver in this subsequent region of confinement is acted on frictionally by overlapped moving surfaces which tend to roll or rotate the sliver about its axis in the reverse of the direction in which the sliver tends to be rotated by the action of the disks in the initial region of confinement.

The two disks, one rotating clockwise and the other counterclockwise, thus not only serve to confine the sliver and keep all of its fibers advancing toward the front drafting elements but also constitute a means for first rotating the sliver about its own axis in one direction and then rotating the sliver about its axis in the opposite direction. The extent of this rotation of the sliver may be varied by varying the loading of the disks and hence the grip they have upon the sliver.

In the typical cotton system to which the invention is shown as applied in the drawings, the sliver, or more specifically the roving shown, has the usual twist which is imparted to it by the speeders in the drawing room. This twist is sufilcient to give the roving lengthwise strength enough for handling and feeding of the roving, but is not suillcient to prevent the bers from In the application of the invention to thetypibeing drawn past each other in the drafting. As

applied to this typical cotton roving, the apparatus may advantageously be operated as shown in Fig. 3, first to rotate the roving about its axis in a direction and vamount such as to remove its initial twist, and then to rotate the roving about its axis in the opposite direction with the result of twisting it up again.

Observations made with apparatus such as shown in the drawings, but employing a top disk made of transparent glass, show that the portion of the roving extending from the line of nip X-X of the rolls l2,Y I3 to the line of centers Y-Y of the disks becomes approximately free from twist as shown in Fig. 3. This is advantageous in permitting any long fibers that may extend back from the front rolls into this untwisted portion to be drafted easily, without un# due resistance resulting from their long length. Such observations also show that from approximately the line of centers Y-Y of the disks to the line of nip Z-Z of the front drafting rolls the roving receives twist which runs preferentially to the most attenuated part of the roving at the entrance to the nip of the front drafting rolls. The twist thus imparted to the roving compacts the fibers together, holds the short fibers back so that they conform to the travel of the main bulk of the roving, restrains the short fibers from splitting ofir from the remainder of the roving, and delivers a consolidated roving to the front rolls, in turn reducing the tendency the woolen system is useful in strengthening the y drafting sliver and equallzing its bulk.

I claim:

1. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for confining the sliver being drafted, said confining means comprising a rotatable member having an end surface positioned to engage the sliver approximately in a plane which is approximately parallel to said line of contact of the front set of drafting elements, said surface being rotatable about an axis which is approximately perpendicular thereto and which is oifset from the line of travel of the sliver, said surface having components of motion in a forward direction along said line of travel of the sliver, and a further member positioned to press the sliver against said end surface, said two members being mounted in opposition to engage the sliver between them.

2. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of Contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for conning the sliver being drafted, said confining means comprising a rotatable member having an end surface positioned y to engage the sliver approximately in a plane contact of the front set of drafting elements and to said line of contact of the back set of drafting elements, said surface being rotatablel about an axis which is approximately perpendicular thereto and which is offset from the line of travel of the sliver, said surface having components of motion in a. forward direction along said line of travel of the sliver, and a further member positioned to press the sliver against said end surface, said two members being mounted in opposition to engage the sliver between them.

3. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least e. line of contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for confining the sliver being drafted, said confining means comprising a rotatable member having an end` surface positioned to engage the sliver approximately in a plane which is approximately coincident with said line of contact of the front set of drafting elements, said surface being rotatable about an axis which is approximately perpendicular thereto and which is offset from the line of travel of the sliver, said surface having components of motion in a forward direction along said line of travel of the sliver, and a further member positioned to press the sliver against said end surface, said two members being mounted in opposition to engage the sliver between them.

4. In apparatus arranged tok draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for confining the sliver being drafted, said confining means comprising a rotatable member having an end surface positioned to engage the sliver approximately in a plane which is approximately parallel to said line of contact of the front set of drafting elements, said surface being rotatable about an axis which is approximately perpendicular thereto and which is offset from the line of travel of the sliver, Said surface having components of motion in a forward direction along said line of travel of the sliver, and a further member positioned to press the sliver against said end surface, said two members being mounted in opposition to engage the sliver between them, the sliver-engaging surfaces of said front drafting elements approaching each other in arcuate paths having a space between them and said rotatable member extending into said space.

5. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact-and driven so as to establish a draft of the sliver between said sets, and means between said sets for confining the sliver being drafted, and confining means comprising a rotatable member having an end surface positioned to engage the sliver approximately in a. plane which is approximately parallel to said line of contact of the front set of drafting elements, said surface being rotatable about an axis which is approximately perpendicular thereto to press the sliver against said end surface, Sald two members being mounted in opposition to engage the sliver between them, the sliver-engaging surfaces of said front drafting elements apassassa "preaching each other in arcuate paths having a space between them. the sliver-engaging surfaces of said back drafting elements leaving each other in arcuate paths having a space between them, and said rotatable member extending into` both of said spaces.

6. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven sov as to establish a draft of the sliver between said sets, and means between said sets for confining the sliver being drafted, said means comprising two rotatable members having their end surfaces positioned to engage the sliver approximately in a plane which is approximately parallel to said line of contact of the front set of drafting elements, the axes l line of travel of the sliver, and said end surfaces each having components of motion in a forward direction aiongvsaid line of travel of the sliver. said two members being mounted in opposition to engage the sliver between them, the sliverengaging surfaces of said iront drafting elements approaching each other in arcuate paths having a space between them and said rotatable members extending into said space.

sliver, front and back Asetsof, drafting elements each adapted to grip the sliver `at at least a line of contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for confining the sliver being drafted, said means comprising two rotatable members having their end surfaces positioned vtoengage the sliver approximately in a plane which 'is approximately parallel to said line ofcontact of the front set of drafting elementsand to said line of contact of the back set of drafting elements, the axes of rotation of saidfmlembers being approximately perpendicular to such plane and offset from the line of travel of the sliver,- and said end surfaces each having components of motion in a, forward direction along said line `oftravel of the sliver, said two members being mounted in opposition to engage the sliver between them.

8. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for confining the sliver being drafted, said means comprising tworotatable members havingtheir end surfaces positioned to engage the sliver approximately in a plane which is approximately coincident with said line of contact of the front set of drafting elements, the

axes of rotation of said members being approxisliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for connning the sliver bein drafted, said means comprising two rotatable members having their end surfaces positioned to engage the sliver approximately in a plane which is approximatelyparallel to said line of contact of the front set of drafting elements, the axes of rotation of said members being approximately perpendicular to such plane and offset from the 10. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven so as to establish a draft of. the sliver between said sets, and means between said Asets for vconfining the sliver being drafted, said means comprising two rotatable members having their end surfaces positioned to 'engage the sliver approximately in a plane which is approximately parallel to said line of contact of the front set of drafting elements, the axes of rotation of said members -being approximately perpendicular to 4such plane and offset from the line of travel of the sliver, and said end surfaces each having components of motion in a forward direction along said line of travel of the sliver, said twcmembers being mounted in opposition to engage the sliver between them, the sliverengaging surfaces of said front drafting elements approaching each other in arcuate'paths having a space between them, the sliver-engaging surfaces of said back drafting elements leaving each other in arcuate paths having a space between them, and said rotatable members extending into both of said spaces.

1l. In apparatus arranged to draft a textile sliver, drafting elements cooperatingto grip the sliver at at least a line of contact and draft the sliver, and a pair of rotatable members having end surfaces disposed to conne between them the sliver approaching -said drafting elements and positioned to engage said sliver approximately in a plane which is approximately parallel to said line of contact of said drafting elements. the axes of rotation of said members being approximately perpendicular to such plane and located, oifset from each other, on opposite sides of the line of travel of the sliver. each such rotatable end surface having, along said line of travel, components of motion in a forward direction. and lateral components of motion cooperating with the other rotatable end surface to rotate the sliver around its axis first in one direction and then in the opposite direction.

12. In apparatus arranged to draft a textile sliver, drafting elements cooperating to grip the sliver at at least a line of contact and draft the sliver, and a pair'of rotatable members having end surfaces 'disposed to confine between them the sliver approaching said drafting elements and positioned to engage said sliver approximately in a plane which is approximately coincident with said line of contact of said drafting elements, the axes of rotation of said members being approximately perpendicular to such plane and located, offset from each other, on opposite sides of the line of travel of the sliver,A

each such rotatable end surface having. along said line of travel, components of motion in a forward direction, and lateral components of motion cooperating with the other rotatable end surface to rotate the sliver around its axis rst sliver, at at least a line of contact"and draft the sliver, and a pair of rotatable members having end surfaces disposed to confine between them the sliver approaching said drafting elements and positioned to engage said sliver approximately in a plane which is approximately parallel to said line of contact of said drafting elements. the axes of rotation of said members being approximately perpendicular to such plane and located, oifset from each other, on opposite sides of the line of travel of the sliver, each such rotatable end surface having, along said line of travel. components of motion ina lforward direction, and lateral components of motion cooperating with the other rotatable end surface to rotate the sliver around its axis first in one direction and then in the opposite direction, the sliverengaging surfaces of said drafting elements approaching each other in arcuate pathsfhaving a space between them and said rotatable members extending into said space.

14. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for confining the sliver being drafted, said means comprising two rotatable members having their end surfaces positioned to engage the sliver approximately in a plane which is approximately parallel to said line of contact of thefront set of drafting elements, the axes of rotation of said members being approximately perpendicular to such plane and offset from the line of travel of the sliver and on opposite sides thereof, and said end surfaces each having components of motion in a forward direction along said line of travel of the sliver, said two members being mounted in opposition to engage the sliver between them.

15. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven so as to establish a draft of the sliver between said sets, and means be tween said sets for confining the sliver being drafted, said means comprising two rotatable members having their end surfaces positioned to engage the sliver approximately in a. plane which is approximately parallel to said line of contact f of the front set of drafting elements and to Said line of contact of the back set of drafting elements, the axes of rotation of said members being approximately perpendicular to such plane and onset from the line of travel of the sliver and on opposite sides thereof, and said end surfaces each having components of motion in a forward direction along said line of travel of the sliver, said two members being mounted in opposition to engage the sliver between them.

16. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line asaassa of contact and driven so as to establish a draft l2 offset from the line of travel of the sliver and on opposite sides thereof,v and said end surfaces each having components of motion in a forward direction along said line of travel of the sliver, said two members being mountedin opposition to engage the sliver between them.

17. In apparatus arranged tojdraft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for conning the sliver bei!!! drafted, said means comprising two rotatable members having their end surfaces positioned to engage the sliver approximately in a plane which is approximately parallel to said line of contact of the front set of drafting elements. the axes of rotation of said members being approximately perpendicular to such plane and odset from the line of travel of the sliver and on opposite sides thereof, and said end surfaces each having components of motion in a forward direction along said line of travel of the sliver, said two members being mounted in opposition to engage the sliver between them. the sliver-engaging surfaces of said front drafting elements approaching each other in arcuate paths having4 a space between them and said rotatable members extending into said space.

18. In apparatus arranged to draft a textile sliver, front and back sets of drafting elements each adapted to grip the sliver at at least a line of contact and driven so as to establish a draft of the sliver between said sets, and means between said sets for confining the sliver being drafted, said means comprising two rotatable membershaving their end surfaces positioned to engage the sliver approximately in a plane which is approximately parallel to said line of contact of the front set of drafting elements, the axes of'rotation of said members being approximately perpendicular to such plane and offset from the line of travel of the -sllver and on opposite sides EDWARD J. ABBUIT.

The following references are of record in the ille of this patent: f

UNTED STATES PATENTS France Aug. 13, 1928 Certificate of' Correction Patent No. 2,522,332 September 12, 1950 EDWARD J. ABBOTT It is hereby certied that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 8, line 61, for the Word and read said;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent OfIoe.

Signed and sealed this 12th day of December, A. D. 1950.

[SEAL] THOMAS F. MURPHY,

Assistant Gommz'ssz'oner of Patents.