US2197638A - Manufacture of yarn - Google Patents

Description

April 16, 1940. HAINv 2,197,638

MANUFACTURE OF YARN Filed July 12, 1959 2 Sheets-Sheet 1 INVENTOR, Motilolm a/(In,

April 16, 1940. M. HAIN 2,197,638

' MANUFACTURE OF YARN Filed July 12, 1939 I 2 Shets-Sheet 2 my I LN WW2- INVENTOR, Ma, (160L171, ie/ n,

ATTORNEY.

Patented Apr. 16, 1940 UNITED STATES PATENT "OFFICE I I Claims.

Oneobject of this invention is to provide a drawing system, especially for use in drawing jute or other best fiber, not involving the use of gill mechanism whereby sliver not twisted or of the more slowly rotated retaining roll-pair- Due to this spacing of the roll--pairs the part of the sliver at any time undergoing actual drawing may be said to'include three classes of fibers-those nipped by the drawing rolls alone, those nipped by the retaining rolls alone, and those not nipped by eitherroll-pair. Imperfect drawing usually occurs because the fibers of the third class are not actually subject to true drawing but are advanced only by the adhesion existing between them and those of thefirst class or actually nipped by the drawing rolls. Such imperfect drawing means a sliver which is not uniform in gauge, being too bunchy in some places and too lean in others. In the effort to overcome this fault pressure on the sliver between the two roll-pairs has been resorted to, as by rolls driven in the direction to favor the advance of the sliver but at a speed less than that of the drawing rolls so to impose a drag on the fibers of the third class and thus overcome the adhesion between them' and the fibers of the first class. This application of pressure, usually resorted to in the case of shortfibered sliver, as cotton, of course reduces the 4 non-uniformity in gauge of the sliver by the holding-back of some of the vagrant or thirdclass fibers, but it cannot, unqualified, result in the inevitable holding-back of more than the minor portion of the vagrant fibers, at least in 45 the case of long-fiber (as jute) sliver, as considerable experimenting by me has shown. Some qualifying factor must be present in the case of the long-fiber sliver if more than a comparatively few of the vagrant fibers-are to be held 50 back. This qualifying factor I have discovered to be a definite positioning of the pressure. Thus:

In two different cross-sections of a sliver taken between the roll-pairs at opposite sides of a as median point between them, the ratios of the first-class to third-class fibers are not the same. In the section at the retaining rollside of such point there will be more of the vagrant fibers to a given number of the first-class fibers than V at the other side, to wit, because the trailing ends 8 of many of the fibers at the latter side reach past said point to the other side. Therefore retaining rolls, or closer to them than to the drawing. rolls, to wit, where there is a relatively superior abundance of the vagrant fibers in proportion to fibers of the first class and where they will therefore be more effectively subject to the holding-back pressure than to the pulling (adhesion) eifort of the first-class fibers.- 15

To obtain the pressure I use a certain system of rolls, per se known. But, toprevent the sliver bunching up behind such rolls, I rotate the latter at a certain speed, to wit, approximating that of the retaining rolls, such speed being suit- 20 able for holding back the vagrant fibers and still favoring the advance of the sliver incident to the drawing.

In the spinning machine there will usually be a number of units each comprising a spinner 25 or spinning means and a drawing system, and when the sliver of any unit breaks between said means and system it is desirable to provide for stopping thedrawing as to that unit. Assuming said system to include the aforesaid pressure 30 means, for effecting the stopping I provide for simultaneously applying a brake to the sliver relatively back of the retaining rolls and terminating the coaction of said pressure means and retaining rolls with the drawing rolls in effecting 35 the draft. Since the sliver following the breaking thereof continues more or less to be delivered by the drawing system, the delivered portion usually has to be removed in order to piece up the sliver. This should not be done so that the new end of the sliver will be back of the drawing rolls and thus inaccessible; According to my invention, therefore, when the brake is applied and the coaction of the pressure means and retaining rolls with the drawing rolls in efiecting draftis terminated, a parting of the sliver is 'caused to occur at a convenient point, to wit,

substantially if not quite at the drawing rolls, which it will be.understood continue running. so In the drawings, 7 Fig. 1 shows mainly in side elevation but partly in section a drawing system embodying. the invention;

Fig. 2 is a plan of what is shown in Fig. 1 taken a in a plane between a certain rolls 6-40; and

Fig. 3 is a plan. partly in section, of a part of the means for stopping the drawing.

Ila designates the drawing rolls of which roll i is fixed to a constantly rotating shaft! and roll in. has its axial portion 3, as trunnions. supported by guides 5 of the frame 4, this roll being held bearing a suitable pressure against roll I by any well-known means (not shown).

6-6a designates the retaining rolls, fluted as usual and above the drawing rolls and of which roll 6 is fixed to a shaft I, constantly rotating at a suitably less speed than that of shaft 2, and roll 6a is here journaled in bearings 8a of the forked forward arm of a lever 8 fulcrumed in frame 4 at 40. and carrying on its rear arm a weight 9 to hold roll 6a bearing against roll 6.

Between rolls IIa and Ma is arranged the mentioned pressure means, thus: On a constantly rotated shaft Illa is fixed a roll It. A pair of rolls ll bear against the periphery of roll I 0 and these are free to rotate independently of each other in a carrier l2 pivoted in the forward arm of a lever l3 fulcrumed between its ends in the frame at 40 and having its rear arm first bent downwardly and then back and carrying a weight All the axes of the pivots and bearings described are here horizontal and parallel. The pivot of carrier I2 is in a plane cutting roll it and extending between rolls ll, wherefore the latter rolls when both are under pressure bear against roll Ill with substantially equal pressure.

fork Ila and the In this example the pivoting axis of the device- 'll-l2 is offset with respect to its center of gravity so that when the pressure is withdrawn it bears with only the upper roll against roll l0.

Lever l3 may be equipped with a fork |3a forming a sliver guide and projecting forwardly between the upper roll II and rolls 6-611. And above the latter rolls there may be a fork l5 forming another sliver guide and fast to the frame 4.

The sliver it extends over a guide it atop the frame, down through guide l5, between rolls 6-6a, through guide l3a, between rolls l0ll, between rolls l-l a and then through the usual spout I1 and a suitably adjustable grooved guide l8 to and through the cap l9 of the usual spinning unit.

Assume the unit to be in operation: A zone of the sliver, from nip :1: to nip :1: in Fig. 1, of less width than the length of substantially any fiber of the sliver exists under pressure; and the rolls lO-H exert an advancing influence on the silver at a speed betweenthose ofthe drawing and retaining rolls. Hence a state of friction between all the fibers within said zone exists, wherefore those fibers which are not nipped by the drawing rolls are held by this friction against advance merely by such bond as may be existing between them and those actually so nipped, wherefore the drawing proceeds uniformly, or without bunching.

Fast to the frame between guides 15 and I6 is a bracket 20 and fast to this bracket is a fixed clamping member 2| having a crotch to'receive the sliver and presenting thereto a rounded sur crank lever 23 one arm of which upstands and the other projects rearwardly. A link 24 is pivoted to the former arm and has a forward downbent end pivoted to the lever ll between its cam and its free end, wherefore when such lever is depressed until a lug 22a. thereon encounters member II the pivot between such lever and the link will have passed dead-center so that the lever will be locked in the depressed position. The rear arm of the lever 23 has pivoted thereto and depending therefrom a link 25 which at 25a has a projection under lever I and at 25b is pivoted to lever II.

To stop the action on breakage of the silver between the drawing rolls and the spinning means the hand-lever is depressed which clamps the silver above the retaining rolls and simultaneously, through the parts 24-23-25, causes retraction of roll a and the carrier l2, so that the described normal action of lO-H and 8-6:: ceases. The silver thereupon definitely parts at or near the actual nip of the (still active) drawing rolls, that is to say, not above them where access to the sliver to effect now the piecing would be difiicuit. I account for this as follows: When the brake is applied, the drawing rolls still running and active, the sliver will of course part in some portion thereof under strain at the weakest point. Such point may be anywhere between the brake and the drawing rolls. But when the brake is applied all actual strain or pull on the sliver effected by the retaining rolls and the pressure means simultaneously ceases, so that there remains no tendency of the silver to part between such means and the brake. But said means, nevertheless, presents a certain continued resistance to advance of the sliver under the pull of the drawing rolls, to wit. by the pressure still exerted by and due here to gravity acting on the upper roll ll, so that from the drawing rolls to such roll II the sliver is under strain. That part of the sliver, however, has been fully drawn or attenuated (that is. graduated in strength from roll ll down to the drawing rolls), wherefore the be such as to defeat the primary purpose, the

drawing of the sliver by the coaction of rolls lla and Ma.

Having thus fully described my invention. 'what I claim is:

1. Mechanism for drawing bast sliver comprising pairs of drawing and retaining rolls, means between said pairs and closer to the latter than to the former pair to impose pressure on the silver including a driven roll. two freely rotative rolls and means yieldingly urging the latter rolls against the driven roll, all said rolls having their axes substantially parallel and the nips of the freely rotative rolls being spaced apart a distance less than the length of substantially any fiber of the sliver being drawn, and means to drive one drawing roll and one retaining roll, the former at the superior speed, and also drive said driven roll at a speed between those of the latter drawing roll and relid ill

Wm H including a pair of drawing rolls, other rolls relatively back of said drawing rolls and one oi which is freely rotative and movable toward but retractive from the other oi such rolls, all said rolls having their axes substantially parallel, means to drive one drawing roll and one of said other rolls, the former at the superior weed, andmeans movalole in one direction to brake the sliver at a point relatively back of said other rolls and free the retractive one of the latter rolls and in the opposite direction to free the sliver at said point and urge said retractive roll toward said other roll. w 3. dliver drameans comprising a pair of drawing rolls, a pair of retaining rolls one of which is movable toward but retractive from the other, all said rolls having their axes substantially parallel, coactive means between said pairs to impose pressure on the sliver one of which is retractive from but movable toward the other, means to drive one drawing roll and said other retaining roll, the former at the superior speed, and means movable in one direction to brake the sliver at a point relatively back of the retaining rolls and free the retractive one of said retaining rolls and the retractive one or said coactive means and in the opposite directlon to free the sliver at said point and move the retractive one toward the other of said retaining rolls and the retractive one toward the other of said coactive means.

4. Sliver drawing means comprising a pair of drawing rolls, a pair of retaining rolls relatively back of the drawing rolls and one of which is movable toward but retractive from the other, a driven roll between said pairs, two pressure rolls coactive with the driven roll, a carrier in which the pressure rolls are journaled, a memher movable tod but retractive from the driven roll and adording a pivot for the carrier, the axes of all said rolls and the pivot being substantially parallel and said pivot being in a plane between the axes of the pressure rolls and cutting the driven roll and said carrier being normally urged to turn on its pivot in one direction, means to drive one drawing roll, (said driven roll and the other retaining roll at such speeds that said driven roll will rotate slower than the drawing rolls and said other retaining roll will rotate slower than said driven roll, and means movable in one direction to brake the sliver at a point relatively back of the retainlng rolls and free said member for retraction from the driven roll and tree the retraotive retainlng roll for retraction from the other retainlngrroll and in the opposite direction to tree the sliver at said point and urge the retractlve roll toward the other retaining roll and said member toward the driven roll.

5. Sliver drawing means comprising a pair of drawing rolls, a pair of retaining rolls above the drawing rolls and one of which is movable to ward but retractive from the other, a driven roll at an elevation between the drawing and retaining rollatwopreuurorollslatcralotmd coactive with the driven roll, a carrier in which the pressure rolls are journaled, a member movable toward but retract-lye from thedriven roll and .11 a pivot for the carrier further removed for the driven roll than the axes of the pressure rolls, the axes of all said rolls and the pivot being substantially parallel and said pivot being in a plane between the axes of the pressure rolls and cutting the driven roll and said carrier being normally urged to turn on its pivot in one direction, means to drive one drawing roll, said driven roll and the other retaining roll at such speeds that said driven roll will rotate slower than the drawing rolls and said other retaining roll will rotate slower than said driven 'roll, and means movable in one direction to brake the sliver at a point relatively back of the retaining rolls and free said member for retraction from the driven roll and free the retractive retaining roll for retraction from the other retaining roll and in the opposite direction to free the sliver at said point and urge the retractive roll toward the other retaining roll and said member toward the driven roll.

6. Sllver drawing means comprising a pair of drawing rolls, a pair of retaining rolls relatively back of the drawing rolls andone of which ismovable toward and retractive from the other, a driven roll between said pairs, a device to hold the sliver in contact with the driven roll throughout an arc of its periphery, a member movable toward but retractlve from the driven roll and affording a pivot for said device, the axes of all said rolls and the pivot being substantially parallel and said pivot being in a plane cutting said arc and said device being normally urged to turn on its pivot in one direction, means to drive one drawing roll, said driven roll and the other retaining roll at such speeds that said driven roll will rotate slower than the drawing rolls and said other retaining roll will rotate slower than said driven roll, and means movable in one direction to brake the sliver at a point relatively back or the retaining rolls and free said member for retraction from the driven roll and free the retractive retaining roll for retraction from the other retaining roll and in the opposite direction to free the sliver at said point said member on an axis substantially parallelwith and in a plane between the axes of said freely rotatlve rolls and cutting the driven roll,

and means to drive one drawing roll and one retaining roll, the former at the superior speed,

and also drive said drivenroll at a speed between those of thelatter drawlng'and retaining rolls.

mucous mm.

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