WO2006106274A1

WO2006106274A1 - Method for transforming and treating a textile yarn and implementing device

Info

Publication number: WO2006106274A1
Application number: PCT/FR2006/050313
Authority: WO
Inventors: Serge Costechareyre
Original assignee: Ritm
Priority date: 2005-04-08
Filing date: 2006-04-07
Publication date: 2006-10-12
Also published as: EP1871935A1; FR2884261B1; FR2884261A1

Abstract

The invention concerns a method for providing a synthetic yarn with the appearance of natural fibers, including in combination, either continuously on a common working unit, or in two phases on two separate working units, the following steps: double-twisting or directly cabling the yarn; thermofixing the yarn followed by cooling in tensionless relaxed state; scraping the yarn.

Description

PROCESS FOR TRANSFORMING AND PROCESSING TEXTILE YARN AND DEVICE FOR IMPLEMENTING THE SAME

The invention relates to the technical sector of textile yarn processing, including twisting operations, cabling, methods for conferring crimp son, associated with fastening methods.

More particularly, the invention relates to transformation methods for imparting to synthetic yarns the appearance of a yarn consisting of natural fibers, which consists in combining with the twisting, cabling or crimping operations of the yarn, an additional mechanical transformation. such as scraping, or other processes which have the effect of subdividing, breaking, moving, and / or intermingling the constituent filaments of the yarn to give it a woolly, cottony or silky fibrous appearance. In what follows, the term "scraping" is used to denote these mechanical processes.

Many techniques have been proposed to perform this "scraping" operation and to integrate it into other thread processing devices. The operation is to bring the wire into contact with a mechanical element having an "abrasive surface" by ensuring that there is a relative speed between the wire and this surface. By the term "abrasive surface" is meant in the following, any surface that has either a roughness or a coating with protruding particles or cutting or other, and is able to scrape, hang and / or cut filaments peripherals of a wire when it is brought into contact with it with a certain pressure and relative speed.

It is apparent from the prior art that one of the problems is to treat the entire circumference of the wire by creating a relative speed of the wire relative to the abrasive surface which forms an angle with the axis of the wire itself. Indeed, this angle is essential for the wire has a tendency to roll on itself and that the abrasion process affects its entire circumference.

GB 2076437 shows, for example, a device rotating the abrasive surface. It has also been proposed, as shown by, for example, GB 531161 or GB 548285, to integrate the scraping method associated with a twisting operation, applied to the processing of viscose.

Another problem relates to the treatment of son by processes which will be referred to in what follows by "heat setting". This treatment involves bringing the wire to a given temperature, for a given time and under a given voltage level, so that the material memorizes its morphology and releases internal tensions resulting from upstream transformations. Temperature, treatment times and voltages are parameters that depend on the characteristics of the material and the desired end effect. In general, this process is immediately followed by a cooling phase during which the wire must be subjected to as low a voltage as possible.

For most applications where it is necessary to set a high crimp level, such as for example the production of BCF yarn for the manufacture of carpets, the heat-setting operation is most often carried out, in a second operation, after twisting or wire wiring. For example, this operation is done by placing the coils in a heat-sealing autoclave. More frequently, this operation is done by passing the son in steaming machines, as illustrated by the patent FR 2453927 in which the wire is unwound, deposited on a carpet through a heated chamber and a cooling zone before being removed.

This results in several disadvantages: - The treatment requires recovery of the coils and loading, unloading and handling operations. Scraping is performed on a relatively compact and closed wire since the voltages from the upstream process are not relaxed. The filaments released by the scraping are retracted and fixed anarchically during the heat-setting process affecting the appearance and final touch of the yarn.

If the coils are treated in autoclaves, the intermingling and thermofixation anarchic filaments released by the scratching of the layered superimposed wires in the winding, cause clashes phenomena creating particular difficulties in the reeling of coils such as breakages or surges. If the yarn is treated in steaming machines, the intermingling and uncontrolled thermofixation of the filaments released by the scraping of the son laid in layers on the carpet, cause clipping phenomena when the threads are taken up on the carpet after the cooling zone, these difficulties being particularly important in view of the tension-free state of the wire at that moment. Broken filaments or abrasion-stripped particles being released into the autoclave or into the processing machine, they migrate onto other wires or coils and / or clog the filters of the apparatus. The object of the invention is to solve these problems by proposing a method and a device for transforming a textile thread by a method incorporating a scraping operation.

According to the invention, the method includes either continuously on the same work unit, or in two phases on two separate work units, the following sequence of operations, according to which: the thread is twisted according to a double twist method or it is wired according to a direct wiring method; the wire is subjected to a heat-setting cycle followed by cooling in the relaxed state without tension; the wire is subjected to a scraping operation in a device where it is brought into contact with an abrasive surface with a certain pressure and a relative speed.

According to a preferred embodiment of the invention, the method consists in continuously producing, on the same work unit or working position, the following sequence of operations: the wire is twisted according to a double twist method or it is cable according to a direct wiring method; the wire is passed to a first call member setting the call speed in the pin and thus the twist level of the wire; the wire is muffled on a set consisting of a heated motorized bucket and a return cylinder, on which the wire undergoes a heat-setting cycle; the wire is passed through a cooling zone in a relaxed state, that is to say under a low voltage, or even zero; the wire is passed through a scraping device, where it is brought into contact with an abrasive surface with a certain pressure and a relative speed; the wire is called on a winding or winding system.

The invention proposes a device for advantageously, but not exclusively, the method according to the invention, said device consisting of a working position or a set of juxtaposed working positions, each working position comprising: double twist spindle or direct wiring, associated with means of feeding reels of food; a capstan type first call device, setting the call speed in the pin and thus the twist level of the wire; a thermofixing member consisting of a heated motorized bucket and a return cylinder; a cooling and relaxation zone; a scratching device; a winding or winding system.

According to the invention, the heating bucket has arrangements adapted to control the removal of the wire, which arrangements consist essentially of a longitudinal profile delimiting successive zones, including at least one zone of recovery of the initial crimp and a fixing zone. The heating cup and the return cylinder can be arranged in a thermally insulated enclosure.

According to the invention, the cooling zone is designed to accumulate a certain amount of wire in a relaxed state without tension for a time necessary for its cooling. According to one embodiment, this cooling zone consists of an accumulator consisting of a hollow rectilinear body, disposed in a substantially vertical position or forming with the vertical angle less than 45 °, and whose end, considered the side of the outlet, is frustoconical to create, within said body, a buffer zone braking the output of said wire by avoiding him out directly.

According to another embodiment, this cooling zone is constituted by a relaxation mat where the yarn forms a reserve, the winding speed being adjusted so that the amount of yarn accumulated in reserve is maintained between two predetermined minimum and maximum values.

According to the invention, the scraping device is a member having an abrasive surface brought into contact with the wire under a certain pressure and arranged so that there is a relative speed having an angle with the axis of the wire.

According to a preferred embodiment the scraping device is constituted by at least one element disposed between a fixed wire guide member and a wire guide member performing a back and forth movement, extending perpendicularly to the direction of scrolling of the wire, so that a portion having an abrasive surface is in contact with the wire when it performs its movement back and forth.

Advantageously, the back-and-forth movement used for the scraping operation according to this embodiment is that of the winding system, the scraping device being implanted immediately before the winding system, in the area where the thread evolves in a zone substantially triangular by following the movement of the wire guide of going and coming.

According to this embodiment of the invention the element (s) having an abrasive surface is or are revolving parts, fixed or rotated, arranged such that the wire is subject to circumvent said one or more parts ( s) of revolution according to an angle of loading.

According to an improvement of this embodiment, the at least one of the parts of revolution having an abrasive surface, are rotated at a chosen speed relative to that of the winding system to adjust the winding tension.

According to another embodiment the scraping device consists of a part of revolution rotated on its axis and all or part of the outer surface is abrasive and is brought into contact with the wire, the speed of rotation of the said piece being chosen so that its peripheral speed forms a non-zero angle with respect to the running speed of the wire.

According to another embodiment, the scraping device consists of a part of revolution that is recessed, rotated on its axis and all or part of the internal surface is abrasive and brought into contact with the wire, the speed of rotation of the said piece being chosen so that its peripheral speed forms a non-zero angle with respect to the running speed of the wire.

The invention is described below in more detail using the accompanying figures and drawings in which: The figure is a schematic representation of the method according to the invention.

Figure 2 is a schematic representation of a heat setting device consisting of a motorized profiled bucket and heated, combined with a return cylinder.

Figure 3 is a more detailed view of an example profile of the profiled bucket.

Figure 4 shows the schematic representation of an embodiment of the accumulator device for cooling and relaxation of the wire.

Figure 5 shows the schematic representation of another embodiment of the accumulator device for cooling and relaxing the wire.

Figure 6 shows the schematic representation of an embodiment of the scraping device.

Figure 7 shows the schematic representation of another embodiment of the scraping device.

Figure 8 shows the schematic representation of the integration of the scraping device with a system of back and forth. FIG. 9 shows in perspective an exemplary embodiment according to the principle represented in FIG. 8.

Figure 10 shows in perspective a variant of Figure 9 with two profiles.

Figure 11 shows in perspective another embodiment of passing the wire between two parallel abrasive surfaces.

FIG. 12 shows the photo of a yarn obtained by means of the process according to the invention corresponding to the first example. Figure 13 shows the comparison of two son, one obtained by scraping before heat-setting, the other, according to the invention, by scraping after heat-setting, corresponding to the second example.

The purpose of the yarn transformation method according to the invention is to carry out a twisting or direct cabling twisting operation, a mechanical abrasion transformation to give the yarn a waxy, cottony or silky appearance and feel and heat-setting, intended to fix the crimp of the wire.

According to an essential characteristic, the mechanical transformation by abrasion, or scraping, is carried out after heat-setting.

According to a preferred embodiment of the invention, the transformation method consists of treating the wire in a single operation, according to the sequence illustrated in FIG.

According to the invention, a wire (F) is arranged in the form of a winding or spool (1) in a double-twist spindle (2), and is passed through the spindle according to a known threading method of a spindle double twist. Or, according to an alternative not shown, two son are arranged one in a direct wiring pin and the other in an associated unwinding system, the two son being passed through the pin according to the known threading method of a direct wiring pin.

At the output of the spindle the thread (F) that is twisted (or wired) goes into a first call (3). According to a preferred embodiment, this call system is for example of the capstan type consisting of a motorized call cylinder (4) associated with a second return cylinder (5) motorized or not. The thread (F) is muffled around the assembly forming a sufficient number of turns for the drive of the wire is carried out without slippage. By passing in the first call (3), the wire (F) is therefore set in motion at a controlled speed which determines, in relation to the speed of the spindle, the number of twists per meter received in the spindle (2) by twisted or wired wire (F). It will be observed that the tension of the thread (F) following the method of twisting or direct cabling in the spindle (2) is supported by this first call (3). The wire (F) is therefore delivered to the output of the first call (3) at a speed equal to the circumferential speed of the motor cylinder.

After the first call, the wire then passes into a heat setting means (6) consisting of a motorized and heated rotary cup (8) associated with a second return cylinder (7), motorized or not and heated or not.

Importantly, the heated rotary cup (8) has arrangements for controlling the removal of the wire. These arrangements are constituted by a longitudinal profile of the bucket shaped to delimit successive and continuous zones extending over its length. The profile is such that it delimits at least two zones, namely, a zone (8a) of recovery of the initial crimp and a zone (8c) of fixation. Preferably, a zone (8b) of residual withdrawal is arranged between these two zones.

FIG. 5 shows an example of a profile according to the invention which delimits a recovery zone (8a), and a fixing zone (8c), as well as a residual intermediate withdrawal zone (8b). It can be seen that the recovery zone (8a) has a mean angle of taper (α) and that the residual shrink zone (8b) has a mean angle of taper (β), the angle (α) being greater than the angle (β). The fixing zone (8c) is here substantially cylindrical. We observe also that the length of the attachment zone (8c) is greater than the sum of the lengths of the other two zones (8a and 8b).

As shown in FIG. 2, the yarn (F) is muffled around the heating bucket assembly (8) - return cylinder (7):

A sufficient number of turns is formed in the zone (8a) for taking up the initial crimping of the heating bucket, so that the wire has time to be heated by heat transfer and retracted to resume its initial crimp. For this, the winding zone has a conical profile, for example, so that the successive peripheral speeds of the wire are degressive from one winding to the other. A sufficient number of turns is formed in the zone (8c) for fixing the heating cup, so that the wire reaches its core temperature at heart.

The number of loops required for each zone, as well as the number of possible additional turns in the zones of transition or residual withdrawal (8b), results from the experiment, for example according to the nature and the title of the wire ( F) worked.

The heating bucket assembly (8) - return cylinder (7) can be arranged in an enclosure (not shown in the diagrams), thermally insulated, and having openings for the entry and exit of the wire. It is possible to have the heating means in this chamber, and / or to inject fluids therein, for example steam, which contributes to heating, moistening or treating the wire.

After thermofixation, the wire (F) is cooled in a relaxed state, that is to say under a low voltage or zero. This operation consists of accumulating the wire on a support, for a time long enough to return to a temperature substantially below the fixing temperature.

According to an embodiment illustrated in Figure 4, the relaxation is performed in an accumulation device (9), consisting of a belt conveyor (10). The forward speed of the belt (16) and the downstream wire feed speed (F) are adjusted so that the amount of yarn accumulated in reserve is maintained between two predetermined minimum and maximum values.

According to another embodiment illustrated in FIG. 5, the relaxation is carried out in an accumulation device (9) consisting of an elongated hollow body (17), preferably rectilinear and arranged in a vertical position or forming a lower angle at 45 ° to the vertical. The lower end of said accumulation device (17) has a frustoconical shape to create, inside the body, a buffer zone (17b) braking the output of the wire by avoiding it to exit directly under the effect of gravity . The feed rate of the yarn (F) downstream is adjusted so that the amount of yarn accumulated in reserve in the body (17) is maintained between two predetermined minimum and maximum values.

Whatever the embodiment, the wire (F) can be distributed in the storage member (9) by a depositing mode resulting from a relative movement between a member guiding the upstream wire (18) and the body accumulator (9) itself. This movement can be a reciprocating movement reciprocating, or a continuous or alternating rotation. This relative movement can be created by moving the guide member of the wire upstream (18) or by moving the member (9) itself. Whatever the embodiment, the wire (F) can pass to the output of the accumulator member (9) by a stripping device (19). This device aims to remove the tendrils that the thread tends to do on itself when released. It consists in restoring a certain tension to the wire, for example, by passing it with a certain arc of loading on parallel bars (19) arranged perpendicularly to its direction of unwinding.

After heat setting, the wire passes into a scraping device (11), where it is brought into contact with an abrasive surface (12) with a certain pressure and a relative speed having an angle with its axis of the wire.

According to an embodiment illustrated in FIG. 6, the scraping device consists of a part of revolution rotated about its axis and all or part of the external surface (12) of which is abrasive and is brought into contact with the wire (F). The rotational speed of said workpiece is chosen so that its peripheral speed forms an angle (γ) which is non-zero with respect to the running speed of the wire.

According to another embodiment, illustrated in FIG. 7, the scraping device consists of a part of revolution that is recessed, rotated on its axis and all or part of the internal surface (12) is abrasive and set in motion. contact with the wire (F). The speed of rotation of the said part is chosen so that its peripheral speed forms a non-zero angle (γ) with respect to the speed of travel of the wire.

According to a preferred embodiment of the invention, illustrated by FIGS. 8, 9, 10 and 11, the scraping device is constituted by at least one element (21) disposed between a fixed guide member (22) of the wire and a yarn guiding member reciprocating (20) and extending perpendicular to the running direction of the wire, such that a portion having an abrasive surface is in contact with the wire when it moves back and forth. According to this embodiment, the reciprocating motion creates an additional component of relative speed of the wire (F) relative to the abrasive surface which is perpendicular to its forward speed. It can be deduced that the back and forth motion must have a reversal time at the extremities as short as possible, so that the time during which the additional component vanishes by changing direction is negligible.

According to this embodiment, a particularly advantageous integration of the scraping device consists in implanting the device in the zone of movement of the wire in its reciprocating motion generated by a winding system (13) forming coils (14). say "crossed". It is briefly recalled here that a cross-coil is obtained by winding the wire on a cylindrical support rotated, the wire being distributed along the generatrix of said cylinder by reciprocating between two positions which delimit the width of the coil. The winding speed and the speed of the reciprocating reciprocating movement are combined so that the wire is wound in substantially helical turns, the pitch of which is reversed at each end, the layers superimposed by crossing one another. The reversal at the ends of the back-and-forth movement, for the formation of crossed rolls, is extremely rapid.

According to this embodiment of the invention the element or elements (21) having an abrasive surface (12), are parts of revolution, fixed or rotated, arranged such that the wire is subject to circumvent said one or more cylinders according to a corner angle. According to an improvement of this embodiment, at least one of the elements (21) of revolution having an abrasive surface (12) is rotated at a speed chosen with respect to that of the winding system

(13) to adjust the winding voltage. For example, the peripheral speed of the element (21) can be adjusted to be slightly less than the winding speed to recreate a sufficient winding voltage. Or on the contrary, the peripheral speed of the element (21) can be adjusted to be slightly greater than the winding speed to lower the tension created by the friction of the wire in the scraper and thus obtain a correct winding voltage.

According to an alternative embodiment of this embodiment, the scraping system (11) comprises two elongate sections (21) having substantially parallel surfaces between which the wire is subjected to pass, said parallel surfaces being applied against each other. other with an adjustable force determining a pressure exerted on the wire.

It is of course possible to add other complementary treatments upstream, intercalated, or downstream such as, for example and without limitation, the application of liquids, intermixing by jet of fluid, drawing on systems additional calls ....) without departing from the scope of the present application, since the basic operations described in the description are performed in the order presented.

Two non-limiting examples of application of the invention are given below.

First example: BCF polypropylene yarn of 2100 Dtex. Twisting in a double twist spindle at 105 T / m. Heat setting temperature on heating cup = 21O ⁰ C. Relaxation time and cooling = 1 min. Scraping and winding speed = 79 m / min. Reference is made to Figure 12 which shows the result obtained.

Second example:

Two BCF polypropylene yarns of 2100 Dtex. Wiring in a direct wiring pin at 105 T / m. - Heat-setting temperature on heating cup = 21O ⁰ C.

Relaxation time and cooling = 3 mn 30s. Scraping speed and winding = 45 m / min.

Referring to Figure 13 which shows the result obtained (23). By comparison, there is shown in the same figure 13 a similar wire (24) obtained by a direct wiring method (same equipment, same spindle speed), then scraping (same device on reception), followed by heat-fixing (same process achieved in a second step).

The advantages are apparent from the description. Especially :

A complete transformation of the wire involving twisting, heat setting and scraping is carried out in a single operation and on the same machine or working position, and therefore without recovery or intermediate handling. - The scraping process is performed downstream of the heat-setting process.

The effectiveness of scraping and the characteristic of the wire obtained are improved. This avoids the removal and anarchic fixation of the filaments released by scraping. The spun effect and feel of the yarn are not affected by heat setting.

This avoids the difficulties associated with clashes and overvoltages due to the free heat-set filaments, especially in the cooling zone at or unwinding the wires.

The scraping device is particularly simplified by its integration in the winding system, thus benefiting from the back and forth movement of the cross-coil winding. The scraping device is disposed in a particularly accessible area for the wire passage, cleaning, exchange of abrasive surfaces ...

Claims

1. A process for transforming and treating a textile yarn (F) intended to give it the appearance of a thread made of natural fibers, including in combination, either continuously on the same work unit, or in two phases on two separate work units, the following successive steps: the wire is subjected to a double twist operation or direct wiring; the wire is subjected to a thermofixation operation followed by cooling in the relaxed state without tension; the wire is subjected to a scraping operation.

2. Transformation method according to claim 1, characterized in that it carries out continuously, on the same work unit or working position, the sequence of operations: twisting in a spindle (2), the wire (F ) according to a method of double twisting or wiring the wire (F) according to a direct wiring method; passing the wire (F) on a first call member (3) setting the call speed in the pin (2) and thus the twist level of the wire; - Blow the wire (F) on a set (6) consisting of a heated motorized bucket (8) and a return cylinder (7), on which the wire undergoes a heat-setting cycle; passing the wire (F) in a cooling zone (9) in a relaxed state, that is to say under a low voltage, or even zero; - Passing the wire (F) in a scraping device (11), where it is brought into contact with an abrasive surface (12) with a certain pressure and a relative speed, calling the wire on a winding or emptying system (13).

3. Method according to any one of claims 1 or 2, characterized in that the heat-setting cycle undergone by the wire (F) in the assembly (6) consisting of a motorized heated bucket (8) and a deflection cylinder (7), comprises at least one phase of recovery of the initial crimp and a fixing phase.

4. Device for implementing the method according to any one of claims 1 to 3, characterized in that it consists of a working position or a set of juxtaposed working positions, each working position comprising: a double twist or direct wiring spindle (2) associated with means for feeding reels of food; a first call member (3) of the capstan type, setting the call speed in the pin and thus the twist level of the wire; - a thermofixing member (6) consisting of a heated motorized bucket (8) and a return cylinder (7); a cooling zone (9); a scraping device (11); a winding or emptying system (12).

5. Device according to claim 4, characterized in that the cooling zone consists of means of accumulating the wire for the time necessary for cooling in a relaxed state, that is to say at a very low voltage, even zero.

6. Device according to claim 5, characterized in that said cooling zone (9) consists of an accumulator consisting of a hollow rectilinear body (17) disposed in a substantially vertical position or vertically forming a lower able to 45 °, and whose end (17b), considered on the output side, is frustoconical to create, inside said body, a buffer zone preventing the output of said wire by avoiding it to go out directly, under the effect of gravity.

7. Device according to claim 5, characterized in that this cooling zone (9) is constituted by a relaxation mat (16) where the yarn forms a reserve, the winding speed being adjusted so that the amount of yarn accumulated in reserve is maintained between two predetermined minimum and maximum values.

8. Device according to any one of claims 5 to 7, characterized in that the wire (F) is distributed in the cooling zone (9) by a removal mode resulting from a relative movement between an element guiding the wire upstream (18) and the accumulator member (9) itself, this movement being a reciprocating reciprocating movement, or a continuous or alternating rotation and can be created by displacement of the guide member the upstream wire (18) or by moving the member (9) itself.

9. Device according to any one of claims 5 to 8, characterized in that, at the outlet of the cooling zone (9), the wire (F) passes through a deflection device (19) consisting of parallel bars (19). ) arranged perpendicularly to its unwinding direction.

10. Device according to any one of claims 4 to 9, characterized in that the heating cup (8) has arrangements adapted to control the withdrawal of the wire, which arrangements consist essentially of a longitudinal profile defining successive zones, of which at least one initial crimp recovery zone (8a) and an attachment zone (8c).

11. Device according to claim 10, characterized in that a residual withdrawal zone (8b) is arranged between the initial crimp recovery zone (8a) and the attachment zone (8c), and in that the zone of recovery (8a) has a mean angle of taper (α), the residual withdrawal zone (8b) has a mean angle of taper (β), the angle (α) being greater than the angle (β) .

12. Device according to any one of claims 10 to 11, characterized in that the fixing zone (8c) is substantially cylindrical and in that its length is greater than the sum of the lengths of the other two zones (8a and 8b optionally ).

13. Device according to any one of claims 10 to 12, characterized in that the heating cup (8) and the return cylinder (7) are surrounded by a thermally insulated enclosure and having openings for entry and exit wire (F).

14. Device according to any one of claims 4 to 13, characterized in that the scraping device (11) is a member having an abrasive surface (12) brought into contact with the wire under a certain pressure and arranged so that there is a relative speed at an angle to the axis of the wire.

15. Device according to claim 14, characterized in that the scraping device (11) is constituted by at least one element (21) disposed between a guide member of the fixed wire (22) and a guide member of the wire performing a reciprocating movement (20), extending perpendicularly to the direction of travel of the wire (F), such that a portion having an abrasive surface (12) is in contact with the wire (F) when the it follows its movement back and forth.

Device according to claim 15, characterized in that the back-and-forth movement used for the scraping operation is that of the winding system (13), the scraping device (11) being implanted immediately before the system. winding (13), in the area where the wire (F) evolves in a substantially triangular area following the movement of the guide wire reciprocating (20).

17. Device according to any one of claims 14 to 16, characterized in that the elements (21) are one or parts of revolution, fixed or rotated, arranged so that the wire (F) is subject to bypassing said cylinder or cylinders at a bending angle.

18. Device according to any one of claims 16 to 17, characterized in that the elements (21) are one or parts of revolution, rotated at a speed chosen with respect to that of the winding system (13). to adjust the winding voltage.

19. Device according to any one of claims 15 to 16, characterized in that the scraping device (11) comprises at least two elongated sections (21) have abrasive surfaces (12) substantially parallel between which the wire is subject to passing, said abrasive parallel surfaces (12) being applied against each other with an adjustable force determining a pressure exerted on the wire.

20. Device according to claim 14, characterized in that the scraping device (11) and consisting of a part of revolution rotated on its axis and all or part of the outer surface (12) is abrasive and is placed in contact with the wire (F), the rotational speed of said piece being chosen to its peripheral speed forms a non-zero angle (γ) with respect to the speed of travel of the wire.

21. Device according to claim 14, characterized in that the scraping device (11) and consisting of a hollow part of revolution, rotated on its axis and all or part of the inner surface (12) is abrasive and is brought into contact with the wire, the speed of rotation of said piece being chosen so that the speed its peripheral speed forms a non-zero angle (γ) with respect to the speed of travel of the wire.