EP0378931A1 - Process and apparatus for yarn winding, and a cross-wound bobbin thus obtained - Google Patents

Abstract

According to the invention, after forming the reserve (9) on the outer annular end (6) of the central body (2) of the carrier support (1), a limited quantity of yarn (10) is wound in the form of approximately contiguous turns forming a ring (11) on the central body (2) before the actual cross-winding. The ring (11) is preferably formed towards the end opposite the reserve (9). The ring comprises, for example, 30 to 80 turns of yarn. The invention is applicable, in particular, to the dyeing bobbins on compressible tubes. <IMAGE>

Description

The present invention relates to the winding of a thread in the form of a crossed spool on a textile machine, equipped with a winding system, in particular a spinning machine with released fibers. It relates to a process allowing the formation of a reel, with reserve thread, such that it can be unwound directly for weaving or knitting with great reliability. More particularly, the process of the invention relates to the formation of crossed coils on compressible tubes, said coils being intended for dyeing and being after dyeing unwound directly for weaving or knitting, without it being necessary to carry out a rewinding operation.

It is known that a significant number of breaks in yarn in weaving and knitting are due to a defect in the winding of the supply spool, in particular in the last turns when passing the thread from a given spool to the spool. the next reel, this last wire being attached to the first by the piecing reserve. Most often, there is a phenomenon of attachment of the wire on the support of the coil or a phenomenon of massive supply of wire, leaving in a packet. The latter phenomenon is particularly accentuated when the supply spool is a dye spool, on a compressible tube, which makes it almost compulsory to rewind these dye spools before weaving or knitting.

Now we have found and this is what is the subject of the invention, a process for forming crossed bobbins which overcomes the aforementioned drawback in that it allows perfectly reliable use in weaving and knitting even for bobbins. dyeing on compressible tubes. In known manner, during the winding of the wire on its support, the first few turns are wound on an end zone of the support, external to the winding zone constituting the coil, and form the piecing reserve. According to the invention, after formation of the reserve and before the cross winding, a limited quantity of the wire is wound on a section of the support, inside the winding zone constituting the coil, in the form of approximately contiguous turns whereby a narrow ring of wire.

Unexpectedly, the presence of this ring consisting of approximately contiguous turns, in contact with the support in the zone constituting the spool itself, eliminates any massive detachment of thread, in bundle, during weaving or knitting.

We can try to explain this unexpected result, in particular in the case of dye coils on compressible tubes. Traditionally, after the formation of the reserve, the wire is wound in a helix at an angle to the axis of rotation which is a function of the adopted pitch. The compression of the tube leads to a reduction in the angle of crossing of the wire, which undoubtedly has the consequence of relaxing the layers of wire in contact with the tube. It would be these layers of thread loosened in place that would form the bundles of thread, disrupting the unwinding. The wire ring formed on the tube is not affected during the compression of the tube, since the turns are already substantially contiguous; there is therefore no loosening of the winding at the end of the coil.

Preferably the wire ring is made towards one of the ends of the support and in particular towards the end opposite to the zone where the reserve is located. In fact, during use, the spool being placed on the spool holder with the side of the reserve down and the wire being unwound upwards, it is preferable to minimize friction on the body of the support. place the ring towards the upper part of said support, therefore opposite the reserve.

The formation of the crossed coil, according to the invention, is continuous, when the crossed winding, according to the formation of the ring, is carried out on the support with the same wire. It can be discontinuous, in particular in the so-called spinning looms with beginners, when in a first step we fill the support with the reserve and with the ring and we break the first wire to the right of the ring, then in a second step we attach a second wire, especially a wire during spinning, with the free end of said first wire.

The wire ring is for example produced, after formation of the reserve, by winding the wire along the support in a decreasing step up to the zone of formation of the ring.

It is another object of the invention to protect a device specially designed to implement the above process on a spinning machine with a starter. In known manner, the device for forming a coil of the starter by winding the wire on a support comprises a support drive drum and a wire placement arm having a displacement in an arc of a circle in front of the support in contact with the drive drum. According to the invention, the drum has, opposite the part of the support close to the zone of formation of the ring, a surface having a hollow relief in the form of an endless screw and on the other hand for each coil of the starter the arm is stationary at first short, corresponding to the formation of the reserve, then it moves continuously to the zone of formation of the ring, and finally it is almost stationary in the zone of formation of the ring for a longer time.

The crossed coil of the invention is constituted by the winding of a wire around a support, with from the start to the end of the winding first a few turns of wire in an external zone of the support forming the reserve of reattaching, then a limited quantity of said wire in the form of approximately contiguous turns, and finally the actual cross winding. Preferably, the limited quantity of wire in the form of approximately contiguous turns corresponds to a number of turns comprised between 30 and 80 turns.

Preferably the approximately contiguous turns are located towards the end of the support opposite the reserve.

• La figure 1 est une vue schématique de côté d'un tube compressible pour bobine de teinture.
• La figure 2 est une vue du tube de la figure 1 garni de la réserve et de l'anneau de fil selon l'invention
• La figure 3 est une vue schématique de face du dispositif d'enroulement .

Other characteristics and advantages will appear more clearly on reading the description which will be given of an exemplary embodiment of a crossed coil according to the invention, illustrated by the appended drawing in which:

• Figure 1 is a schematic side view of a compressible tube for dye reel.
• Figure 2 is a view of the tube of Figure 1 filled with the reserve and the wire ring according to the invention
• Figure 3 is a schematic front view of the winding device.

The example which will be described below relates to the formation of a crossed reel on a compressible tube on a spinning equipment known as a starter.

The compressible tube 1 shown in Figure 1 is a hollow plastic tube of generally cylindrical shape. The main body 2 of the tube 1 is largely hollowed out, it comprises a network of cells 3 delimited on the one hand by annular elements 4 and on the other hand by connecting elements in the form of chevrons 5, connecting the elements annular 4, over the entire periphery of the tube 1.

To obtain the compression of the coil, a strong pressure is exerted between the two lateral faces of the latter. Under the effect of pressure, the connecting elements 5 are deformed, causing the annular elements 4 to come together. Stops 6, distributed between the annular elements 4 on the connecting elements 5, limit this deformation and prevent obstruction of the cells. 3.

On either side of the central body 2, the tube has two planar annular ends 6,7 whose diameter is different from that of the central body 2. The first end 6, whose diameter is slightly smaller than that of the central body, corresponds to the training area of the piecing reserve. The second end 7 has an outside diameter slightly greater than that of the central body and an inside diameter very slightly greater than the outside diameter of the first end 6, so as to allow the nesting of two successive tubes during dyeing.

A spinning material is said to start when the formation of the crossed reel is carried out in two distinct stages. In the first step, the tube is placed on a winding device where only the piecing reserve is made on this tube and a cross-wound pre-winding of a reduced quantity of wire. In the second step, the tube thus filled is placed on the actual spinning loom where the free end of the pre-wound wire is sought by a nozzle and attached to the wire in training on the loom.

Usually the crossed pre-winding represents about 70 meters of wire, that is to say a quantity sufficient for this pre-winding to constitute a relatively complete covering of the cells favoring the gripping action of the end. free of thread by suction from the squeegee.

FIG. 2 shows the packed tube according to the invention after the first step has taken place. On the annular end 6 of the tube 1, the reattachment reserve 7 is formed in the form of a few contiguous turns; the free end 9 of the thread 10 on the reserve side, blocked under a few turns, is available for attaching it to weaving or knitting with the start thread of another spool.

Towards the other annular end 7, on the central body 2, the wire 10 is wound in the form of an accumulation of approximately contiguous turns constituting the ring 11. The free end 12 of the wire 10 at the level of the ring 11 is not blocked, it is available for connection with the wire being formed in the second step.

Between the reserve 9 of the ring 11, the wire 10 is wound in a helix with a pitch which decreases from the reserve 9 to the ring 11.

When the wire 10 is gripped by the nozzle, the tube 1 turns on itself, the free end 12 of the wire is released in line with the ring 11, in a plane perpendicular to the axis of rotation of the tube 1 As a result, this end 12 is sucked in and taken up by the nozzle without any difficulty.

Once the end 12 has been sucked in, the reattachment system integrated into the machine connects this end 12 of the wire 10 to the wire being formed, and the cross winding of this wire around the central body 2 of the tube 1 continues so conventional.

The rotation of the spool on the spinning machine is obtained by rotating rollers generally made of rubber, on which the external surface of the tube or of the spool being formed is applied.

It has been noted that the presence of the ring 11 at one of the rollers improved the training at the start of the operation; undoubtedly the attachment of the ring by the roller is better than that obtained with the plastic tube, the surface condition and surface geometry may vary.

In an exemplary embodiment, the quantity of wire 10 pre-wound on the same tube 1 was for the invention from 12 to 15 meters, compared to the usual 70 meters of pre-winding. Thus the pre-winding according to the invention requires significantly less yarn than according to the conventional method. This has a double advantage. On the one hand, the time for producing this pre-winding is reduced accordingly and the productivity of the machine is improved. On the other hand, in the event of an error in the choice of the yarn 1 constituting the pre-winding, the defect in weaving or knitting due to this error will be reduced by the same amount.

The pre-winding of the first step is carried out on the device shown very diagrammatically in FIG. 3. This device comprises a drive drum 13, which is a cylinder rotating around its horizontal axis 14. It also includes an arm 15, mounted pivoting about an axis 16. The arm 15 is terminated by a clamp 17, able to grip the wire and move it during the pivoting of the arm 15. Compared to the conventional pre-winding device, only the shape of the drum 13. This is usually grooved to ensure the formation of helical turns, for cross-winding traditional. According to the invention, the drum 13 has its outer surface which has a hollow relief in the form of an endless screw.

The operation of the device is as follows. The tube 10 is applied against the drum 13, with the annular end 6 corresponding to the reserve placed on the side where the arm 15 is in the high position. The wire 10, coming from a reel not shown and held by the clamp 17, is presented by the arm 15 on the tube 1 according to the following sequence. Firstly, the arm 15 remains opposite the annular end 6, during the winding of the first few turns of the connecting reserve 9. Secondly, the arm 15 pivots about its axis 16 describing an arc of circle, in front of the tube 1 and the drum 13, this circular arc passing in front of the line of tangency 18 of the tube 1 and of the drum 13 towards the central part of the central body 2 of the tube 1. During this pivoting, the wire 10 is wound around the tube 1 first at an important step and then at a decreasing step until the arm is in the low position. The third step corresponds to the end of pivoting of the arm 15; the wire 10 is wound according to the approximately contiguous turns for a determined time to constitute the ring 11, then it is cut.

The invention is not limited to the embodiment which has been described in a non-exhaustive manner, but covers all variants thereof. In particular, it is understood that it is up to the person skilled in the art to determine the location where the ring on the tube must be situated as a function of the type of support and of winding material which it has. For example, in the case of a compressible tube for dyeing reels, the tube can be designed so that the deformation of the compressed tube is mainly in the middle part of the central body of the tube; in this case, the ring will preferably be placed towards one of the ends of the central body in an uncompressed part so that it is well irrigated by the dye bath passing through the cells from inside the tube.

Furthermore, the invention is not limited to dyeing reels on compressible tubes. The ease of grip of the end of the wire by the nozzle, resulting from the position of this end on the ring, is such that the invention proves to be advantageous even for non-compressible coils.

Claims (11)

1. Method for forming a crossed coil by winding a wire (10) on a support (1), of the type according to which the first few turns are wound on an end zone (6) of the support (1), outside to the winding zone (2) constituting the coil, and form the reattachment reserve (9), characterized in that after formation of the reserve and before the cross winding, a limited quantity of the wire (10) is wound on a section of the support, inside the winding zone (2) constituting the coil, in the form of approximately contiguous turns whereby a narrow ring (11) of wire is produced on said section. 2. Method according to claim 1 characterized in that the zone in which the ring (11) is produced is located towards one of the ends of the winding zone (2) constituting the coil. 3. Method according to claim 2 characterized in that the ring (9) is produced towards the end of the winding zone (2), opposite to the end zone (6) where the reserve is located (9) . 4. Method according to one of claims 1 to 3 characterized in that, after formation of the reserve, it consists in winding the wire (10) on the support (1) by moving said wire (10) along the support ( 1) according to a step which decreases to the zone of formation of the ring (11). 5. Method according to claim 1 characterized in that the actual cross winding is carried out on the support (1) continuously, after the formation of the ring (11) and without breaking the wire (10). 6. Method according to claim 1, applied to spinning with a starter, characterized in that in a first step we fill the support with the reserve (9) and with the ring (11) and we break the first wire (10) in line with the ring (11), then in a second step, a second wire, in particular a wire in the course of spinning, is attached to the free end (12) of said first wire (10). 7. The method of claim 1 applied to the formation of a crossed reel for dyeing, characterized in that the thread is wound on a compressible plastic tube. 8. Device for implementing the method according to claim 6 of the type comprising a drum (13) for driving the support (1) in rotation and a placement arm (15) of the wire (10), said arm (15 ) having a displacement in an arc in front of the support (1) in contact with the drum (13), characterized in that the drum (13) has, opposite the part of the support close to the zone of formation of the ring (11), a surface having a hollow relief in the form of an endless screw and on the other hand for each coil the arm is stationary at first in a short time, corresponding to the formation of the reserve, then it moves continuously until 'at the ring formation zone, and finally it is almost stationary in the ring formation zone for a longer time. 9. Crossed coil constituted by the winding of a wire (10) around a support, comprising in a known manner at the start of the winding a few turns of wire on an annular end (6) of the support forming the reserve (9 ) of piecing, characterized in that it comprises, on the central body (2) of the support (1) and before the actual cross winding, a winding of a limited quantity of the wire (10) in the form of coils approximately contiguous (9), forming a ring of wire. 10. Cross coil according to claim 9 characterized in that the ring (11) comprises from 30 to 80 turns of the wire (10). 11. Crossed coil according to one of claims 9 or 10 characterized in that the ring (11) is located towards the end of the central body (2) opposite the annular end (6) of the piecing reserve ( 9).

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