FR2523159A1 - METHOD OF REFINING A SET OF TEXTILE FIBERS OF FLAT, RIBBON, WICK, SHEAR: HIGH PERFORMANCE STRETCHING - Google Patents

Abstract

The invention relates to a method allowing the stretching of an assembly of fibers in mattress, tablecloth, tape, wick, by application of a single seam in order to ensure a rolling of layers of fibers during which and on which CONTROLLED NORMAL PRESSURE EXERCISED. THE PROCESS IMPLETS AT LEAST ONE PAIR OF "FIBER SUPPORTS" MORE OR LESS TOTALLY SUPERPOSED AND BETWEEN WHICH THE FIBERS ARE DRIVEN ACCORDING TO A SPEED GRADIENT DETERMINED BY THE RATIO OF THE SPEEDS: VV OF THE TWO MATCHING SUPPORTS. DEPENDING ON THE WIDTH OF THE ASSEMBLY OF FIBERS TO BE STRETCHED, THE "FIBER SUPPORTS" ARE CONSTITUTED BY STRIPS OR BANDS, METALLIC OR NOT, FLAT OR COATED WITH ANY POINTED GASKETS, OR WITH ANY JOINTS, TO IMPROVE THE TRAINING AND THE DEPLOYMENT OF FIBERS SUBJECT TO LAMINATION. THE NORMAL FORCES REQUIRED DURING STRETCHING ARE APPLIED TO THE SUPPORTS BY SPRING, CYLINDER, ELECTRIC MAGNET, LOAD LEVER ... AND DISTRIBUTED TO AREAS IN CONTACT WITH THE FIBERS, BY TENSIONING THE SUPPORTS, OR THROUGH PLATES OR ROLLERS OR PINCH ROLLERS.

Description

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  The present invention relates to a high-performance drawing method for reducing (refining) the mass of the cross-section of a set of textile fibers presented in surface form (mattress, web, sail) or in linear form (ribbon, wick ) by applying a cisai lement, further improving disentangling and paralleling the fibers. High performance results in an increase most often extremely significant compared to what happens for the known systems of quality (mass regularity, resistance, elongation and fracture energy, regularity of resistance and elongation of rupture ); ripening rates (or "draw ratio") applicable up to extremely high, unusual values, and the extreme limit, theoretically necessary to move from any previous primary stage to the final presentation stage; versatility of use ("flexibility") with regard to the possible use without adjustment, to all short or long fibers, on the same machine, and to the instantaneous modification (thus without long adjustment) of the drawing ratio desired, by simple variation of speed, thus

  computerization and automatic control of the machine are easily possible.

  Indeed, according to the conventional and known methods of implementation in spinning and spinning itself, the reduction in the mass of the cross section of a set of textile fibers (in "web" as in the drummer for example, in "ribbon" as drawbench or open-end open-end spinning looms for example, in "wick" or bench wick, as in continuous spin ring and slider for example), essentially by stretching between pair of input cylinders (or "supply or supply") (1, 2) (FIG. 1) and pair of output rollers (1 '(FIG. 1) with tangential velocity V 2 of rotation greater than that of pz input cylinders: the ratio (v 2 / vl) of these two speeds determines the

  the theoretical drawdown rate, which does not take account of any slippage

  fibers; the pinching is done only by the pressures P 15 and 16.

  Despite the many additions such as intermediate cylinders (3 l (Figure 2) or guide strips (4) (Figure 2) or, as in the case of implementation of "long" fibers (wool or fibers free) for example) of "hedgehog" cylinders (5) (FIG. 3), moving needlefields (6) (FIG. 4) or any other intermediate rotating or moving support: (FIG. 4b), all known processes are based on the drawing given by: positive call of the output cylinders (1 ', 2') with respect to the cylinders (1, 2 ')

previous upstream.

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  In fact, according to a new approach to the origin of this intervention, the process of refining the linear density or surface density of the fibers in a section can be likened to a flow of fibers By analogy, with

  what happens for fluids (Figure 5 abc) the lamellar flow in

  parallels sliding parallel to each other (7) relative to the others (81,

  is best done by applying what is called in rheology a "shear

  simply "on flat layers (Figure 5 a), or on layers cocylin-

  driques, telescopically (Figure 5b).

  According to this principle, the upper layer (9) (of fibers) is driven by the application of a force (10) while the lower layer (11) is retained relative to the upper layers by the application of a force (12) The effect

  the normal torque of the tangential forces (10/12) must be compensated by the

  cation of normal forces (13) and (14) (Figure 5c), otherwise the tendency to rotate would result in dislocation of the layers and conditions for

  an ideal sliding of the layers would no longer be ensured.

  However, in conventional known stretching systems, sliding can not

  normally take place only between the pinch points (fig 1 C 4) of the cylinders

  1.2 / 1, 2 yes strips (4), according to the pressures (15) and (1 applied (fig 1) at the points of clamping, but where o is carried out the sliding proper fibers, by drawing, c that is, in the interval between the nip points, there is little or no normal force exerted on the sliding surfaces, which by reaction with the torque (1 O / 12) causes the dislocation (17) ( fig 1) of all the fibers: because of this, some fibers are found badly or not controlled in their movement, which is then carried out in packets or clusters

  fibers of greater or lesser mass.

  In practice, this results in an irregularity of section (linear or surface density) all the greater than the theoretical irregularity (predictable from the mathematical Poisson model of a perfectly stretched linear or surface fabric) than the control of the movement of fibers

is less equiprobable.

  To better strive towards the conditions required for an equi-

  likely fibers, one must ensure the conditions of simple shear unfilled in known systems; on the other hand, the system according to the invention makes it possible to fulfill these conditions and thus to avoid the drawbacks and restrictive limits, particularly in drawing ratio of the known systems.

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  Indeed, the system according to the invention performs the refining of a set of fibers presented in the form of mattress, tablecloth (= "textile surface") or in the form of ribbon or wick (linear Etextile ') by simple shear: the relative sliding of the layers of fibers is done by the application (FIG. 6 a) of an "upper fiber support" (19) driving the fibers at the higher speed v 2 (and not equal as in the known systems) at the speed v1 "of a lower fiber support" (18) while applying during the sliding of the fiber layers (24), the normal forces C 20, 21): in a first versic

  simple practical realization of the system, the fiber supports are la-

  Of the same type as those used in conventional drawing on bench or on a loom, the normal forces are applied on the axes of the drive rollers and distributed over the fibers because of the tension given by the tensioners (25), adjustable or not (FIG.

  with (I) and (2) rotating at speed v1 and (1 ') C 2') at speed v 2.

  Of course, the arrangement of the longitudinal axis of flow of the fibers may be horizontal, vertical, or inclined, especially if one wants to take advantage of the gravity to perfect the guiding of the flow of the fibers and / or the maintenance on the supports of fibers, or between the supports or between the supply, even the exit, and the supports Also the qualifications

  "superior" and "lower" are correct only in the case of a pre-existing system.

  horizontally as in the figures These designations have now been

  naked for understanding, even for the case of a vertical flow, or the supports are vertical; similarly, the speed v 2 (higher than the speed vl)

  can be given to the lower support, the role played by the two supports

to be interchanged.

  The variants relating to this system described by the invention relate to the nature of the supports, the arrangement of the supports, the "cascade" combination of this system, repeated to ensure a gradual and gradual stretch, the way to apply the normal forces , the feeding and the output, the extension to the manufacture of a core wire in combination with this

stretching system.

  Of course, it is possible to combine the various contributions of the following two variants, which follow According to a first variant, the "fiber support" may be a strip or strip, metallic or not, fixed or extensible, grooved, notched, or coated with any other lining (pointed, toothed, with more or less rough surface)

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  to ensure the effectiveness of the training or to ensure at the same time as the main function of stretching, also other functions such as detangling, parallelization, carding (which facilitate the flow of fibrel and which are also facilitated by the shear given by the system of the invention In a second variant, the lower (418) and upper (19) supports are

  shifted according to FIG. 7 by a certain fixed or adjustable value "C", do not exceed

  normally not the length of the longest fibers worked.

  According to a third variant, the initial device according to the invention is mounted in successive repetitions to ensure a staggering of the stretches and / or to change the applied speed gradient, according to the constan or variable speed ratios v 2 v 3 vv yz vl V 2'V Vz and in fixed or variable number An example of such an embodiment is shown in FIG. 8a with three drawing stages: the support (19) (at speed v 2) offset with respect to the support ( 18) (at speed vl) ensures a first stretching

  V 2 theoretically, the support (26) at velocity v 3 provides a second theoretical stretching.

  that of v VI and the support (27) & speed V 4 ensures the third stretch v 2

V P

  theoretical of v 4 / v 3; to do this, we can choose the spacings el, e 2, e 3, e 4, depending on the length of the fibers with possibly the implementation in the spacings of a cu several supports or guides, such as roller (28 ) (2 e) or rollers grooved or décolletés, or else: condenser, (semi-) entonnoi for example, for the maintenance of the fibers in the zones of separation e (fig 8 a) having only a support, "superior "or" inferior "instead of a superior

and lower superimposed.

  According to a fourth variant, which concerns only linear textiles, the support can be produced at the limit by the fibers themselves of the ribbon, twisted to give the normal pressure by the centripetal effect of the torsion, and thus ensure a shear of the type telescopic (fig Sb) in analogy

  with what happens for the flow of a fluid in a capillary.

  The known method of application of a false twist twister whistle (45) conventional spinning type woolen carded (according to Fig 9a) or by stretcher-wringer

  (trade mark "Drehstreckwerk" according to fig 9 b) is only a particular case

  of shearing in a telescopic but truncated flow.

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  It is remarkable to note that patents and actual false-twist applications in drawing only relate to the final stage before rewinding to

  coil (50) of continuous spinning ring, but anyway the rates of stretching

  In this fourth variant, the application of the whistle or of a stretch-wringer ("Drehstreckwerk") is done more upstream, therefore before the final stretching on continuous spinning, for example on the pinbank, to the drawing benches, also by cascade mounting with two or more elements in series, alternately with or without false twists, as shown by way of example, FIG. 10 relating to three stages with three elements (30) (31). ) and (32) alternately false twists, to obtain a sufficient and effective stretching. According to a fifth variant, the normal forces (springs, cylinders, electromagnets, levers and the like) (20) (21) (FIG. 6 abc) can be transmitted to the supports: either via plates (22) (23). (Figure 6b), on which slide the supports and which distribute on these the applied forces

(20) (21),

  or to avoid the disadvantage of parasitic friction of the supports on the fixed plates, by means of rollers (28), rollers (29) (FIG. 6c) or any other device holding the supports under a corresponding pressure

  to the normal force required in the "ab" interval.

  According to a sixth variant, the power supply of the device can be realized by

  any known system, delivering fibers in mattresses or sheets (for the application

  "surface") or wicking ribbon (for the application in "linear") including also by the systems releasing the fibers (for example by breaker, by selector) of the type of those used in so-called fiber-free spinning

("open end").

  According to a seventh variant, the device can be equipped with accessories

  at the entrance or exit only possibly between the entrance and the exit (

  in the event of shifting according to the second and / or third * zariante) such as funnel, condenser, roller or roll grooved Or no, décolleté 3 or not, or any other part, with or without pinching fibers, improving the guiding

  fibers or allowing them to slide Figure 11 shows an example of

  at the inlet and the outlet are mounted low-profile rollers (33) rotating on smooth rollers (34) for drawing> snxi a system with offset supports, according to the ratio of the speeds v 2 / v 1 of the supports straps (18) and (19); Such an achievement has made it possible to reach stretching rates in the range of 50 as easily from wicks of wool as cotton by giving yarns of exceptional quality: systematic superiority in regularity.

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  mass, cleanliness, and dynamometric properties, compared to yarns

  of the same title obtained from the same materials on conventional spinning

  ring rings for cotton on the one hand and for wool on the other hand, but with stretching rates of not more than 30 for cotton and 20 for wool; According to an eighth variant, a continuous filament yarn may be inserted at any stage of the stretching process according to the invention: before, during or at the end of stretching proper, to allow the production of a "thread" at

  Soul, that is to say, the center or heart of which is constituted differently than the

  where are discontinuous fibers.

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Claims (6)

  1) Process for refining (stretching) a set of textile fibers in mattresses, sheets, ribbon, wicks characterized by the application of a single shear, made by rolling layers of fibers (24) with   strips or webs of "lower" (18) and "upper" fibers (1 i -   superimposed (and between which the fibers are rolled) because of their different speeds, and on which normal forces apply (2 O '   ? 1) acting on the fibers especially in the sliding zone, it is   say during the actual rolling.   2) Method according to claim 1, characterized in that the fiber supports, metal or not, fixed or extensible, are notched, grooved, or filled with rafters or not, or coated with any other lining: spikes, teeth, or other reliefs to improve training and / or deployment fibers subjected to rolling.   3) Process according to claim 1 or claim 2, characterized by a shift of the supports, to be superimposed only on a part in which the rolling effect and the application of normal forces are assured, 4) Method characterized by the series combination, in cascade of two or   several drawing trains according to any one of the preceding claims.   to allow progressive stretching with an equal draw ratio or   variable at each drawing stage.   Method according to claim 1 and claim 4, characterized by concentric telescopic cocylindrical shell shearing   applying only to the case of ribbon or wick, where the external support is   by the superficial fibers themselves twisted for example by false torsion, whose centripetal effect ensures the application of normal pressure   and in particular according to the series assembly of elements with false alternating twists   born or not, of the same values or not.   6) Process according to any one of claims 1 to 4, characterized   by the application of the normal forces (20) (21) by means of plates, rollers, rollers which transmit to the supports the pressures which are conferred by spring, cylinder, electromagnet, charged levers and the like   7) Method according to any one of the preceding claims, characterized   by a breaker or fiber selector feed of the type of   those mounted in so-called open-end spinning.   8) Method according to any one of the preceding claims, characterized   in that the feed and / or the outlet are equipped with a guide such as: funnel, condenser, roller or roller grooved or not, decottened or not, or any other part with or without nipping fibers improving the guiding of the flow of fibers.   9) Method according to any one of the preceding claims, characterized   by inserting a continuous filament yarn, before, during or at the end   stretching itself, in order to make a soul thread.