US2569957A - Production of staple fibers of artificial materials such as rayon - Google Patents

Description

1951 w. H. SCH IDER PRODUCTION OF STAPLE F RS OF ARTIFICIAL MATERIALS SU Filed June CH AS RAYON Patented Oct. 2, 1951 assess? PRODUCTION OF STAPLE FIBERS OF ARTI- FICIAL MATERIALS SUCH AS RAY ON Walter Helvetio Schneider, Zurich, Switzerland Application June 23, 1947, Serial No. 756,488 In Great Britain July 1, 1946 5 Claims. (Cl. 19-1) This invention concerns improvements relating to the production of strands (slivers, roves, or yarns) of staple fibres, especially staple fibres of rayon or other artificial fibrous material, from a plurality of continuous filaments or from fibres, hereinafter termed filaments, which are, at least, longer than the said staple length.

According to the invention, apparatus for the purpose set forth comprises in combination with pairs of front and rear drawing rollers and cutting means located between the said rollers. a roller or cushionhaving a continuous but flexible filament-guiding surface and arranged to defiect the filaments from a straight course between the rear and front rollers whilst permitting a reduction of the deflection of individual filaments as their ends are gripped by the front rollers, the cutting means being arranged so that it is engaged by tensioned filaments upon the said reduction of their deflection. The roller or cushion may have a fluid filling.

In an advantageous form of the apparatus, means producing a light pressure on the filaments beyond the cutting means is provided for controlling the fibres out oil. The deflecting roller or cushion, followed by the cutting means, is arranged just beyond the real-rollers and an endless apron is arranged to travel from over a guide, located under the deflecting and cutting means, to the said front rollers. The apron may be provided, between the guide and the front rollers, with a portion inclined downwardly in relation to the guide.

Apparatus in accordance with the invention permits of continuous or long filaments being cut effectively and economically into fibres of required uniform staple length and delivered continuously in a manner permitting of their conversion into the form of slivers or roves which are capable of being drafted and spun without previous carding and combing.

A preferred form of apparatus in accordance with the invention will now be described by way of example and with reference to the accompanying diagrammatic drawings, in which- Fig. 1 is a side elevation view of the apparatus. and

Fig. 2 a plan view thereof.

2 nip between the rear rollers I with a good spread,

, i, e. in the form of a thin band or fleece of uni- Drawing apparatus shown comprises a rear From the deflecting roller 4, the filaments 3 are carried forward to the nip of the front or drawing oil. rollers 2 with the assistance of an endless apron or belt 5 which runs around the lower roller 2 and an additional roller 6 and over a guid 1 extending forwardly from under the roller 4. Cutting means, as shown a fixed knife 8, is arranged a short distance in front of the roller 4, its cutting edge being disposed with a certain clearance above the normal path of the filaments on the apron 5. The cutting means extends parallel to the rollers at a distance from the nip of the front rollers 2 equal to the required staple length. Beyond the cutting means, a light roller 9 runs upon the filaments carried by the apron 5 over the guide 'i. The front portion of the apron is inclined to the horizontal between the front end of the guide I and the rollers 2.

Means for initially breaking the filaments may comprise a fixed and a movable clamp adapted for gripping the fleece at points separated by approximately th staple length so that the filaments can be stretched and broken by moving the latter clamp away from the former. In this breaking operation which need be performed once only, at the commencement of working, the ends or points of division of the filaments are well distributed over the first staple length, that is they are at different cross-sections in. neighbouring filaments.

Due to this distribution of the points of division throughout the staple length, the ends of the filaments will reach the nip of the front rollers 2 at different times, so that the filaments will be gripped and .drawn independently of each other. The draft due to the greater circumferential speed of the rollers 2 will thus cause each filament, as soon as its end reaches the nip of the said rollers, to be individually stretched between the rollers I and 2. The downwardly deflected filament thus tends to be brought into a straighter course between the said rollers and the straightening permitted by local deformation of the roller 4 is arranged to be sufllcient for the tensioned filament to be brought into contact with the knife 8,so that a fibre of the required length will be cut oil. The roller 4 continues ments from coming into contact with the knife. The light roller 9 controls the severed fibre as it contracts and is drawn forward after cutting. The new end of the filament is caused to re-enter the fleece by the roller 4 whose local deformation will be eliminated by the action of its liquid filling directly the stretched filament is cut. For light deniermaterial, a slight air draft may be directed upon the fleece to assist the re-entry of the filament ends.

With the front portion of the apron 5 inclined downwardly as shown, filaments stretched into contact with the knife 8 extend freely between the rollers I and the front edge of the guide 1 only. Beyond the said edge, they still rest on the apron 5. It is easier to keep the filaments parallel over this short free distance than over the whole distance from the rollers I to the rollers 2.

Beyond the front rollers 2, a sliver I is formed by, for instance, compressing the fleece in a conductor or guide means II. The sliverv may then be conveyed into a can with the assistance of a pair of delivery rollers I2, or twist may be introduced and the material wound upon a bobbin. The former procedure will be more usual for coarse denier fibres and the latter for finer denier fibres.

Means other than those described above may be employed for deflecting and guiding the fleece and for severing the filaments, depending upon the character of the fibrous material and other practical requirements. In place of the rotary cushionor roller 4, use may be made of a nonrotary cushion or pad with a deformable deflecting-surface of flexible non-porous material and a filling of liquid or gas. In the case of hard materials, the knife 8 may be replaced by a fine endless band-saw which is resharpened continuously as it travels round. For other materials, an alternative severing means is a heated wire or edge which melts the filaments at the point of contact. Instead of the apron and guide I, a fixed guide may be used having a concave surface between the rollers l and the knife 8 and extending to the vicinity of the rollers 2.

I claim:

1. Apparatus for converting textile filaments, particularly of rayon, into a strand of staple fibers, comprising in combination with pairs of front and rear drawing rollers and cutting means located between the said rollers, a cushion which 2. Apparatus for converting textile filaments. particularlyof rayon, into a strand of staple fibers, comprising, in combination pairs of front has a continuous flexible filament-guiding sur- 7 face constituted by a thin skin having a fluid filling, arranged to deflect the filaments from a straight course between the rear and front rollers while permitting a reduction of the deflection of individual filaments as their ends are gripped by the front rollers, the cutting means being arranged so that it is engaged by tensioned filaments upon the said reduction of their deflection.

and rear drawing rollers, cutting means located between the said rollers, a roller which has a continuous but flexible filament-guiding surface constituted by a thin skin having a fluid filling arranged to deflect the filaments from a straight course between the rear and front rollers while permitting a reduction of the deflection of individual filaments as their ends are gripped by the front rollers, the cutting means being arranged so that it is engaged by tensioned filaments upon the said reduction of their deflection.

3. Apparatus according to claim 1, and comprising also an apron and a guide for the said apron, wherein the deflecting cushion, located before the cutting means with respect to the direction of travel of the filaments, is arranged Just beyond the rear rollers and the endless apron is arranged to travel in contact with the deflected filaments from over the guide, located under the deflecting and cutting means, to the front rollers.

4. Apparatus according to claim 1, and comprising also an apron and a guide for the said apron, wherein the deflecting cushion, located before the cutting means with respect to the direction of travel of the filaments, is arranged just beyond the rear rollers and the is arranged to travel in contact with the deflected filaments from over the guide, located under the deflecting and cutting means, to the front rollers, said apron being provided, between the guide and the front rollers, with a portion inclined downwardly in relation to the guide.

5. Apparatus according to claim 1, and comprising also an apron and a guide for the said apron, the deflecting cushion, which is located before the cutting means with'respect to the direction of travel of the filaments, being arranged just beyond the rear rollers, and the endless apron being arranged to travel'in contact with the deflected filaments from over the guide, located under the deflecting and cutting means, to the front rollers, an additional roller being disposed in contact with the filaments and above the apron and guide beyond the cutting means.

WALTER HELVETIO SCHNEIDER.

REFERENCES CITED The following references are of record in the flle of this patent:

UNITED STATES PATENTS endless apron

Claims (1)

1. APPARATUS FOR CONVERTING TEXTILE FILAMENTS, PARTICULARLY OF RAYON, INTO A STRAND OF STAPLE FIBERS, COMPRISING IN COMBINATION WITH PAIRS OF FRONT AND REAR DRAWING ROLLERS AND CUTTING MEANS LOCATED BETWEEN THE SAID ROLLERS, A CUSHION WHICH HAS A CONTINUOUS FLEXIBLE FILAMENT-GUIDING SURFACE CONSTITUTED BY A THIN SKIN HAVING A FLUID FILLING, ARRANGED TO DEFLECT THE FILAMENTS FROM A STRAIGHT COURSE BETWEEN THE REAR AND FRONT ROLLERS WHILE PERMITTING A REDUCTION OF THE DEFLECTION OF INDIVIDUAL FILAMENTS AS THEIR ENDS ARE GRIPPED BY THE FRONT ROLLERS, THE CUTTING MEANS BEING ARRANGED SO THAT IT IS ENGAGED BY TENSIONED FILAMENTS UPON THE SAID REDUCTION OF THEIR DEFLECTION.

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