US2304902A - Textile apparatus - Google Patents

Description

DeC. 15, 1.942.' w 1 ELVlN ETAL 2,304,902

TEXTILE APPARATUS Filed Dec. 19, 1940 Patented Dec. l5, 1942 'raxrmr maaa'rrrs wimm J. Elvin. mann, ma., .ne Elmer a.

Stahl, Meyeredale, Pa., asslgnora to Celaneee Corporation of America, a corporation o! Del- Application December 19, 1940, Serial No. 370,740

ZCIalml.

This invention relates to a novel apparatus for the production of slubby yarns from staple fibers, and relates more particularly to an apparatus for the production of slubby yarns wherein the slubs are formed substantially at random along the length of the yarn.

An object of our invention is the provision in a cotton spinning frame of means for controllably and intermittently altering the speed of the drafting rolls of the spinning frame so as to cause an uneven drafting of the roving with the resultant formation of slubs.

Another object of our invention is the provision in a spinning vframe provided with means for'altering the speed of the drafting rolls of means for causing the speed change to take place automatically.

Still another object of our invention is the production from staple ,flbers oi.' slubby or doupioni yarns which may be used for the weaving of shantung-type fabrics.

Other objects of our invention will appear from the following detailed description.

Slubby or thick and thin yarns have been prepared artificially in the form of continuous lament yarns by extruding a suitable solution through orifices into coagulative or evaporative media under certain conditions or by interrupting or varying the continuity with which the illaments are drawn from the orifices through which they are being extruded. In the case of natural silk, thick and thin yarns are obtained from cocoons which are spun so closely together that they are joined. In unreeling, the silk nlaments are obtained in a thick and thin form.

It has been proposed to produce slubby yarns from staple fibers. A diiilculty encountered in the production of slubby yarns from staple fibers is that the slubs were obtained at regular intervals or were obtained in closely spaced repeat sequences. This uniformity in the yarn gave the fabrics woven therefrom an undesirable regularity of pattern and detracted from their appearance. To overcome this, many expedients were employed but without substantial success. In accordance with our invention, however, thick and thin yarns may be prepared from staple fibers with the slub formation at irregular intervals along the yarn by applying to the drafting rolls of a. cotton spinning frame means for intermittently altering the speed of said drafting rolls.

Our invention will now be described in greater detail, particularly with reference to the accompanying drawing wherein the preferred embodiment of our invention is shown. It is to be understood, however, that this description is given by way Vof example only and is in no way limitative.

In the drawing:

Fig. 1 is a plan view' of a mechanism for variably driving a set of drafting rolls,

Fig. 2 is a detail view taken along the line 2--2 of Fig. l showing a peripherally slotted cam which operates a make-and-break switch in the electrical circuit which controls the generation of the magnetic flux in one of the clutches, and

Fig. 3 is a detail view taken along the line 3-3 of Fig. l showing a second cam which controls the switch in the electrical circuit which actuates the second clutch.

In Fig. 1 a roving l of staple fibers, which is to be drafted into slub yarn, is shown being drawn from a supply package 5. Roving I 1s passed through a series of pairs of rotating drafting rolls, the upper rolls of each pair not being shownl for the sake of clarity. The drafting rolls comprise a pair of back rolls 6, a pair of intermediate rolls 1, and a pair of front rolls I, all the rolls being driven by suitable means hereinafter described. I'he arrangement of the rolls and the direction of rotation is such that` the roving is nipped between each pair of rolls and is thus drawn forward. The speed of rotation of the front rolls 8 is greater than that of the back rolls 6 and intermediate rolls l, which causes the front rolls l to exert a positive pull on the roving t causing some of the individual fibers which make up the roving to slide forward relative to each other. By maintaining the front drafting rolls 8 at a fixed rotational speed higher than the back and intermediate rolls, the roving is uniformly reduced in diameter and a ilner yarn is formed. The uniform drafting of a roving to a yarn of higher count is an operation well known to the textile art. To form a slubby yarn, however, in accordance with my invention, the rotational speed of the rolls is intermittently varied causing the drafting rolls to permit portions of the roving to pass through without effecting thereon any substantial reduction in diameter.

The means for operating the drafting rolls t, 1 and l is driven by any suitable source of power (not shown) through a shaft 9 which carries a sprocket wheel il keyed thereto. A sprocket chain II operatively connects sprocket wheel il to a sprocket wheel I2, suitably fixed to ashaft i3 as by a screw Il. The rotation of the shaft il drlvesthefrontdraftingrollslbymeansoia sprocket chain Il, operatively connecting a spsockstwheel'llattachedtoashaftllbyascrew nmstantiaily constant rate of detheresultsnt productatalitimegwhich bya variation in the notaof the main driving shaft l. The issuitablyiournaledinandsupportedby bearingsllandll.

llountedontheshaft Ilarethemeansfor prlsesamagneticclutchandlowspeedgeartrain generally indicated by the reference character A andamagnetic clutchandhighspeedgeartrain generally indicated by the reference character B. ThismagneticclutchinassemblyAisshownln disengaged position and consists ofadriving magnednblebodyll slidablykeyedonrotatingshaft llbymeansofakey lla,andadrivenclutchbody Ilfreelymountedontheshaft Ilsothatthe shaft il normally rotates relative thereto, and fixed against longitudinal movement. Integral withthehubofthehousingofclutchboibuisa spur gear 2l which is also freely mounted on the shaft IJ. Gear 2l engages an intermediate gear Ilwhichengagesagearl'lilxedtoasecondshaftl ilbyascrewll. Gearrotatesinandissur portedbyabearingll whileshaftllisjournaled in and supported by bearings Il and 32.

ThehighspeeddrivingassemblyBisshownin engaged position and consists similarly of a drivlng magnetinble body 3l slidably keyed on rototing shaft il by means of a key 34 anda driven clutch body 3l freely mounted on shaft Il and .fixed against longitudinal movement. Integral 'with the hub of the housing of clutch body Il is a spur gear 3l which is also freely mounted on the .shaft Il. Gear Il engages an intermediate gear J1 which engages a gear 3l ilxed to drive shaft 2l by a screw 3l. Gear Il rotates in and is supported bya bearing Il. The rotational movement of drive shaft Il, which, as shown in Fig. l, is being driven by the high speed assembly B, is transmitted to the drafting rolls i and I through a chain drive consisting of a sprocket chain 4i, operatively connecting a sprocket l2 fixed to shaft 2l by a screw 43, to a sprocket wheel M fixed to the shaft 4l of the back drafting rolls C by a screw 4B. The rotation of back rolls 6 drives intermediate rolls 1 through a gear 4l xed to shaft Il by a-screw Il, and a gear 49 fixed to the rolls l as by a screw Il. The intermediate gear through which the rotation of gear Il is transmitted to gear 4l is not shown.

The magnetic clutches are energized by a sultable source of direct current. The circuit for the 'clutch of assembly A comprises a lead wire il which divides at a junction i2 into a wire I3 and a wire I4. 'I'he wire I3 leads into a cam-actuated switch comprising a rotating cam il and a springloaded pawl Il which carries a breaker point I1. Cam Il is fixed to shaft l as by a screw Il. Pawl Il is pivotally attached to a pin 5! and is maintained in contact with the irregular periphery of cam Il by a flat spring 6l which is attached to pawl Il at one end and bears against a pin 6| at the other. The current enters the switch at the lower terminal I! and when the rotation of the cam Il lifts the pawl I6 out of slots Il on to the peripheral edge of the cam, the breaker point Il comes in contact with the breaker point I4 and accesos closes the circuit. The parts of the switch mountedonapanelll'. Whenthecircuit closed, the current flows into wire ll. brush Il and enters the magnetisable. through a collector ring l1. By means of mutable ,amagnetioiluxhcreatedinthemagnetisablebodyllbytheilowofcurrent. The magnetically-induced polarity in the body Il causesittoslidealongtheahaft Ilandkey lts andtonltgetheclutohbody". Therotating magnetisable body Il in frictional contact with clutchbodyllcausesthegearlltobringgeara It and I'Ilnto motion thus rotating shaft Il and therebydraftrollsland'l. Thecurrentpasses through the windings and leaves the msgnetisable boch' through a collector ring Il in contact with a brushllreturningtothepowersourcethrotuh awire 1l. Whenpawlll dropgintothenextslot II on cam Il, the switch opensthe circuit and the clutch in assembly A is de-energized, releasing the clutch and permitting the magnetizable body lltorotatefreelywithshaft Ilindieng'agedrelation with clutch body 2l.

At the same time the clutch of assembly A is released by the opening of the switch, the clutch in assembly B is brought into operation by means of a cam-actuated switch shown in Fig. 3, timed by a second cam to operate alternately with the switch of assembly A. This switch comprises a peripheral cam 1| likewise mounted on shaft l, having projections 12 randomly spaced about the periphery thereof. and a pawl 'I3 pivotally attached to a pin 13' carrying a breaker point 14. The alternate operation of the switches is effected by having the projections 12 spaced about the periphery of cam 'H so that they act in register with the slots on cam 5I as both cams rotate. Thus, as one switch opens, the other simultaneously closes and the clutches operate alternately. 'I'he parts of the switch controlling assembly B are mounted on a panel 14'. Current enters the switch through wire I4 and terminal 15. 'Ihe rotation of cam Il raises the pawl Il upward, as shown, against the tension of a flat spring I6 bearing against pin Il and brings it in contact with a breaker point 11, closing the circuit. 'Ihe current then flows through wire 1l. brush 'Il and enters the magnetizable body 3l by means of a collector ring Il. The current flows through suitable coils in the magnetizable body and creates a magnetic flux, as heretofore described in connection with the operation of the magnetic clutch of the assembly A. The magnetic flux brings the clutch into operation by causing magnetizable body I3 to slide along shaft Il and key Il, and frlctionally engage clutch body 35. This causes the gear 36 to bring gears l1 and Il into operation, thus rotating shaft 2l and operating drafting rolls 6 and 1. The current leaves magnetizable body 3l through a collector ring Il, a brush I2 and a wire I3 joined` to wire l0 at a junction I4 and leading to outlet wire B5. The brushes in assembly A are suitably held in position by a post I8 while the brushes of assembly B are held by a post l1.

Ascanbeseeninl'ig2the shape ofcamll is such that the switch which it operates is usually closed, since pawl N rests upon the outer circular periphery of cam 55 during the greater part of its rotational movement. Thus, draft rolls I and 1 are driven in substantially constant speed relation to draft roll I which, as has been indicated, is rotated at constant speed. In this manner, a uniform draft is applied to the roving l while the clutch-of assembly A is engaged. As

the respective cams 55 and 1| are rotated by shaft 8,' the pawl I8 rises out of slot B3 in cam I! closing the circuit controlling the clutch in assembly A, while the circuit controlling the clutch in assembly B is simultaneously opened as pawl 13 drops on passing one of the projections 12 which are circumferentially registered with slots 63.- Magnetizable body 33 is de-energized releasing clutch body 35, while cam y55 simultaneously brings the clutch of assembly A into operation and drives shaft 28 through the gear train comprising gears 25, 28 and 21. These gears are in a lower ratio than gears I6. Il and 38 and when assembly B is again brought into operation. the higher gear ratio gives the drafting rolls 6 and 1 a sudden increase in rotational speed. This sudden speed-up permits the yarn to pass through the drafting rolls B and1 withoutbeingdrafted and thus a slub or thick place in the yarn remains.

Thechangeinthespeedofthedraftingmlls by the operation of the respective clutches is accomplished smoothly since clutch body 24 and clutch body I are each normally in rotational movement even when disengaged. When clutch body 24 is not being driven by magnetizable body 23 it is rotated freely about shaft I3 since the rotational movement of shaft 2l is transmitted backward to clutch body 24 by the gear train comprising gears 21, 28 and 25. Similarly, clutch body is rotated continuously when not being driven by magnetizable body Il through the gear train comprising gears ll, 31 and 36. The sudden increase in the rotational speed of vdrafting rolls duce a slub yarn-which is singularly free of undesirable regularity of pattern since the slub repeat comes only at widely spaced intervals.

It is to be understood that the foregoing detailed description is merely given by way of'illus- Y tration-and that many variations may be madel therein without departing from the spirit of our invention. v

Having described our invention, what we desire to secure by Letters Patent is:

1. In a mechanism for producing slubby yarns from rovings, the combination with a spinning machine including a plurality of cooperating pairs of drafting rolls, of means for rotating one of said pairs of drafting rolls, means including a plurality of magnetically operated clutches for rotating the cooperating pairs of drafting rolls atalternating variable speeds. and means including a plurality of complementary cams act. ing upon a plurality of make-and-break switches to bring each of said clutches into alternate operation.

2. In a mechanism for producing slubby yarns from rovings, the combination with a spinning machine including front, intermediate and back drafting rolls, of means for driving said front rolls at substantially constant speed and means for rotating both said back and intermediate rolls alternately at different speed, said latter'means including a plurality of magnetically operated clutches each actuating a gear train adapted to cause said back and intermediate rolls to rotate at a different speed relative to the speed of said front roll, said magnetically operated clutches being brought alternately into operative position by a plurality of complementary surface cams acting upon a plurality of make-and-break switches energizing each of said clutches.

WILLIAM J. ELVIN. ELLEER R. STAHL.

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