US2197856A - Manufacture of yarns containing staple fiber from yarns composed of continuous filaments - Google Patents

Description

Apnl 23, 1940. D. FINLAYSON ET AL 2.l97,856

MANUFACTURE OF YARNS CONTAINING STAPLE FIBER FROM YARNS COMPOSED OF CONTINUOUS FILAMENTSf Filed Feb. 4, 1937 350% L. Lmfkacw Patented Apr. 23, 1940 MANUFACTURE OF YARNS CONTAINING STAPLE FIBER FROM YARNS COMPOSED OF CONTINUOUS FILAM'ENTS Donald Finlayson and Leonard Latham, Spondon,

near Derby, England, assignors to Celanese Corporation of America, a corporation of Delaware Application February 4, 1937, Serial No. 124,048

, In Great Britain February 12, 1936 1 Claim. (0]. 19-1) This invention relates to the manufacture of yarns containing staple fibers from yarns composed of continuous filaments.

According to the present invention yarns con- 5 taining staple fibers are produced by continuously drawing yarns composed'of continuous filaments, for example yarns of cellulose acetate artificial silk or the like, over a razor edge in such a way that at intervals along the yarn, some but not all 10 of the filaments are severed.

Besides the yarns composed of continuous filaments of cellulose acetate referred to above, yarns containing continuous filaments of other materials may also be used for the purpose of the invention, for example materials having a basis of other organic derivatives of cellulose, regenerated cellulosic materials, for example cuprammonium artificial silk and viscous artificial silk, and natural silk.

The yarns treated should preferably be lightly twisted but even untwisted yarns may be used provided that suitable means are adopted to maintain the necessary coherence between the severed and the unsevered filaments, for example 5 by sizing or by the insertion during winding of twist which runs back from the collecting device as far, or nearly as far, as the razor edge. On the other hand it is of advantage that the filaments in the yarn should not be so closely packed as to 80 prevent them from spreading somewhat during the severing.

The invention is particularly advantageous when applied to continuous filament yarns whose volume or bulk has been increased, e. g., by sub- 1 jecting the yarn, either on its way to the razor edge or in a previous stage, to a false twisting operation in the course of which the twist inserted in the yarn is set, e. g., by the application of wet steam or other setting agent. In the case of the I false twisting operation of this kind the twist so set in the yarn automatically runs out owing to the nature of the false twisting operation. Alternatively the yarn may, in a previous stage, have been actually twisted prior to or during set- 1 ting of the twist, in which case the twist should preferably be removed. Indeed, in the case either of a twisting or of a false twisting operation carrled out in a previous stage a small quantity of twist in the reverse direction to that set in the yarn may conveniently be imparted to the yarn after the setting and removal of twist. In the case either of a twisting or of a false twist operation, the setting and removal of twist leaves the yarn with a greater bulk than it previously possessed on account of the distortion of the individual filaments, imposed while the yarn was temporarily twisted and retained after untwisting. A yarn whose bulk has been increased in this manher, and which has been given a small degree of reverse twist, is particularly convenient for the purposes of the present invention,

Two forms of apparatus according to the present invention will now'be described in greater detail with reference to the accompanying drawing, in which:

Fig. 1 is a diagrammatic side elevation of an apparatus according to the invention;

Fig; 2 is a front elevation of a part of Fig. 1;

Fig. 3 shows a detail of the apparatus shown in Figs. 1 and 2; and

Fig. 4 shows an alternative method of mounting the blade.

Referring to Figs. 1 and 2, the yarn l is drawn from a. stationary package 2 through a balloon guide 3 and then proceeds directly over an exposed part of the edge of a blade 4 which is of the wafer type commonly employed in safety razors. The blade 4 is provided with a guard 5 having a gap at B in one of its edges through which gap the yarn is caused to pass. The blade 4 and the guard 5 are secured to a holding plate I by means of a nut and bolt 8. The holding plate I is carried, on a bar 9 and is set at an acute angle of, e. g., 45, to the yarn coming to it so that the yarn is drawn past the edge, and the filaments are not instantly and simultaneously severed.

From the edge of the blade at the gap 6 the yarn passes through a pig-tail guide Ill and thence round three rollers ll, l2, l3. The roller II is a driven roller and drives the rollers i2 and I3 by friction. The rollers l2 and 13 drop into slots l4 and I5 in a bracket I6, the slot l4 opening in front of the bracket so that the roller I! may be dropped in in such a way that the yarn is caused to pass over the roller I l, behind the roller I2 and in front of the roller l3. From the roller l3 the yarn proceeds to the guides l1, 18 of a take-up device by means of which they are wound on a package IS.

The guide I0 is carried on a long wire 20 which is pivotally mounted at 2| on the bracket 16. A-U-shaped piece of wire 22 is secured to the wire 20 and engages with a disc 23 obliquely secured to the spindle 24 of the roller I2, as is shown in Fig. 3. The obliquity of the disc 23 causes the wire 20 which is connected to the disc 23 by the U-shaped wire 22 to oscillate about the pivot point 2| so that the pig-tail guide In oscillates to and fro lengthwise of the exposed edge of the blade 4. In this way the yarn is caused to traverse to and fro along the exposed part of the blade. In order to prevent the accumulation of loose severed filaments beneath the blade 4, a nozzle 34 is provided in order to direct a jet of air against the edge of the blade, and blow any loose filaments away. In place of the nozzle 34 there may be employed a rotating brush or a Wiper which may be synchronized with the reciprocation of the thread.

As an alternative to the blade 4 and its mounting means I, 8, 9 there may be employed the device shown in Fig. 4. Here a blade 25 of the safety razor type is secured by means of a screw 26 to an electrically vibrated arm 21. The arm 21 is vibrated by means of an electro-magnet 28 connected to a source of supply of current 29 through a make and break contact 30 carried on the arm 21. The arm 21 is wholly or partly of iron so as to be attracted by the core 3| of the electro-magnet 28 when current is flowing through the electro-magnet. When this occurs, however, the movement of the arm 21 towards the electro-magnet 28 breaks the circuit at the contact 30 and permits the arm 21 to spring back to its initial position, so closing the circuit and re-establishing the current in the electro-magnet 28 so that the cycle is repeated. The yarn l coming from the balloon guide 3 passes through a wire guide 32 carried on supporting bar 33, the blade 25 being disposed over the bar 33 and under the guide 32. The device is adjusted so that the edge of the blade 25 just comes into contact with the yarn passing through the guide 32 in the extreme position of the blade. This device may be obliquely disposed in a position similar to that of the blade 4 and its mounting I, 8, 9 over the balloon guide 3. In this case the pigtail guide In and its mounting 20, 2| and operating means 22, 23 are dispensed with.

When yarn having a crinkle produced by twisting the yarn, setting the twist therein and removing the twist is employed, it is preferable that the take-up package I9 should be rotated at a speed slightly lower than the peripheral speed of the rollers ll, l2 and I3 so that the crinkle is not pulled out by the tension between the take-up package l9 and the roller l3,

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

Apparatus for the production of yarn containing staple fibers from yarns composed of continuous filaments, said apparatus comprising a blade having a razor-like cutting edge, means for continuously drawing yarns composed of continuous filaments past said edge and means for re-, ciprocating the said blade so as to bring its edge intermittently into and out of contact with the yarn whereby at intervals along the yarn some, but not all, of the filaments are severed.

DONALD FINLAYSON. LEONARD LATHAM.

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