The present invention relates to a device for joining fibres during the spinning process of fancy yarn and to a machine and method for spinning fancy yarn that includes said device.

Background of the invention

The production of fancy yarn characterised in that it combines the use of a bundle of base fibres and a bundle of effect fibres of different colours or nature is known.

Patent EP2758572 discloses a first fancy yarn production method wherein a bundle of effect fibres is intermittently added to the bundle of base fibres to form the yarn, while patent WO20153381 1 discloses a second production method wherein the feeding of the bundle of effect fibres and the bundle of base fibres is alternately interrupted to form a yarn that combines alternating sections of effect fibres and base fibres.

Both fancy yarn production methods require the use of devices destined for joining or drawing together the effect fibres and base fibres during the spinning process. These devices are essential for obtaining high-quality yarn.

The use of devices for condensing and/or compacting fibres that include a pneumatic vacuum system for aspiring the fibres through perforated aprons that advance the fibres, once drafted, towards the torsion spindle, is known. These pneumatic devices have proven to be particularly useful in the fancy yarn production process as they make it possible to merge, orient and integrate the effect fibres and base fibres effectively and uniformly in the yarn cross-section.

However, the use of the aforementioned pneumatic devices raises the cost of purchasing and maintaining the spinning machines, since it requires a sophisticated air aspiration system coupled to the outlet of the drafting train. In addition, the energy consumption of these pneumatic devices is very high.

The existence of devices for condensing and/or compacting fibres that dispense with the pneumatic fibre aspiration system is known. Patent EP2758572 describes one of said devices that include a piece having a fibre joining channel configured in the manner of a floating wedge for being disposed at the outlet of the drafting aprons. This piece, configured in the manner of a wedge, is sustained by a support rod which is associated with the pressure arm that sustains the top rollers of the drafting train. The rod is horizontally movable over the pressure arm for adapting the position of the piece to the movement of the fibres.

The device described in the preceding paragraph is useful for joining fibres and has the advantage of being inexpensive, simple and easy to use. However, it has the drawback that it does not adapt to any type of production of fancy yarn. For example, the device described in patent EP2758572 is not suitable for producing fancy yarn of the type wherein the feeding of fibres is interrupted alternately to form yarn that combines sections of effect fibres and sections of base fibres. The need to obtain a device for joining or binding fibres that is simple, inexpensive and that also adapts to any type of production of fancy yarn is therefore evident.

Description of the invention The objective of the present invention is that of providing a device for joining or binding fibres during the spinning process of fancy yarn that is simple and inexpensive and, also, has the advantages described below.

In accordance with this objective, according to a first aspect, the present invention provides a device for joining fibres during the spinning process of fancy yarn, which is characterised in that it comprises a self-supporting piece having a fibre joining channel configured to be inserted between front rollers and intermediate rollers of the drafting train of a machine for spinning fancy yarn, wherein the reverse side of said piece defines a support surface on a bottom front roller, the obverse side of the same piece including a support base on a bar of the drafting train and a fitting arrangement dimensioned to fit said piece against drafting aprons associated with said bar.

According to a second aspect, the present invention provides a machine for spinning fancy yarn that comprises, in each spindle, a fibre drafting train having a pair of rear rollers and a pair of intermediate rollers for feeding a bundle of effect fibres and a bundle of base fibres, said drafting train including a pair of front rollers wherethrough said fancy yarn comes out once the fibres are drafted and which is characterised in that it comprises the claimed device for joining fibres, and in that the self-supporting piece of said device is configured to be inserted between said front rollers and said intermediate rollers such that the surface of the reverse side and the support base of the obverse side of the piece may come into contact respectively with the bottom front roller and with the nose bar of the drafting aprons, said piece being susceptible, in its work position, of being fitted against the drafting aprons in the fitting arrangement envisaged on the obverse side of said piece.

The self-supporting piece of the claimed device is configured with a design (curved surface of the reverse side and base of the obverse side) such that it is supported on a bottom front roller and on a bar of the drafting train, in particular, on the nose bar of the drafting aprons associated with the intermediate rollers. In addition, the piece includes a fitting arrangement dimensioned to fit the piece against the drafting aprons associated with the intermediate rollers.

Due to these characteristics, the piece is sustained on its own, inserted between the intermediate rollers and the front rollers of the drafting train and fitted against the drafting aprons, in such a manner that the fibre joining channel is disposed in a suitable position for receiving and supporting one or various bundles of fibres in parallel. As a result, a self- supporting piece is obtained having a fibre joining channel which adapts to any type of production of fancy yarn.

In particular, the self-supporting piece of the claimed device is suitable for producing either fancy yarn of the type wherein the feeding of the bundle of effect fibres and the bundle of base fibres is interrupted alternately to form yarn combining alternating sections of effect fibres and base fibres or fancy yarn of the type wherein a bundle of effect fibres is added intermittently onto the bundle of base fibres. In both cases, the fibre joining channel of the piece is positioned and fitted to the drafting aprons enveloping the intermediate rollers, in such a manner that said channel may receive and support one or various fibre bundles, in accordance with the type of production, in parallel.

According to a preferred embodiment, said fibre joining channel is envisaged in an upper portion of the self-supporting piece, wherein the reverse side of said upper portion defines a surface configured to adapt to the contour of the top front roller, the obverse side of said upper portion including the entrance of the fibre joining channel.

This upper portion of the self-supporting piece extends and adapts to the shape of the contour of the front rollers, facilitating the joining and controlled insertion of the fibres through the channel that spans the distance between the drafting aprons and the front rollers in the manner of a bridge.

According to the same preferred embodiment, the obverse side of the upper portion of the piece includes a support base configured in the manner of two projections which, in the work position, rest on the nose bar that secures the drafting bags or aprons, on both sides of the drafting aprons associated with said bar.

These projections enable the correct positioning of the joining channel of the piece with respect to the fibre outlet point.

Preferably, the entrance of the fibre joining channel defines a support bed "L" dimensioned to receive one or various bundles of fibres at the outlet of the drafting aprons of the intermediate rollers and, advantageously, said fibre joining channel includes enveloping curved walls that converge in an exit envisaged on the reverse side of the upper portion of the piece.

According to a production method of a type of fancy yarn, a cut end of one of the bundles of fibres can rest on the aforementioned support bed "L" when the feeding of this bundle of fibres is interrupted and waiting to be newly injected.

According to the same preferred embodiment, a lower portion of the self-supporting piece extends from the aforementioned upper portion to occupy, in a work position, a free space "e" between the bottom front roller and the bottom intermediate roller, the obverse side of said lower portion including the fitting arrangement to fit the piece against the drafting aprons and the reverse side of the same lower portion defining the support surface on the bottom front roller.

This lower portion is inserted in the free space "e" between bottom rollers and fitted against the drafting bags or aprons by means of the aforementioned fitting arrangement, facilitating the controlled joining of the fibres in the channel of the upper portion of the same piece.

Advantageously, the lower portion of the self-supporting piece is dimensioned to abut against the nose bar of the drafting aprons when the pressure arm of the drafting train rises and the piece moves to an upper position actuated by the front roller, said same piece being susceptible of being moved to the work position again when the pressure arm descends and comes into contact with the edge of the upper portion of the same piece.

In this manner, the piece is prevented from escaping from its position when the pressure arm of the drafting train rises to perform, for example, a maintenance operation.

Optionally, according to another embodiment, the piece comprises clips, each of which has a fixation flap capable of being inserted under pressure beneath the nose bar of the drafting aprons when the piece is fitted against the drafting aprons.

In this manner, when the pressure arm rises the piece does not move, but rather the fixation flap must be forced out from underneath the nose bar of the drafting aprons in order to remove the piece.

Advantageously, the reverse side of the self-supporting piece includes lateral recesses made on both sides of the curved support surface of the piece, wherein said recesses facilitate the exit of the fibres accumulated between the bottom front roller and said support surface.

According to an embodiment of the claimed machine which corresponds to a first production method of fancy yarn, said machine comprises a processing and control unit:

a. configured in such a manner as to allow the intermittent feeding of a bundle of effect fibres susceptible of passing between said pair of rear rollers while said intermediate rollers continuously feed a bundle of base fibres to the drafting train of the same spindle position of the machine, such that the bundle of effect fibres can be added intermittently onto the bundle of base fibres to form fancy yarn, the fibre joining channel of the self-supporting piece being susceptible of receiving of a set of fibres from the bundle of effect fibres and the bundle of base fibres.

According to an embodiment of the claimed machine that corresponds to a second production method of fancy yarn, said machine comprises a processing and control unit:

a. configured to allow the simultaneous feeding of a bundle of effect fibres and a bundle of base fibres to the drafting train of the same spindle position of the machine, both bundles being susceptible of passing substantially parallel between the pair of rear rollers and the pair of intermediate rollers, and

b. configured to alternately interrupt the feed of one or another bundle of fibres for the purpose of forming fancy yarn that combines different sections of effect fibres and base fibres, the fibre joining channel of said self-supporting piece being susceptible of receiving the two bundles of effect fibres and base fibres at the outlet of the drafting aprons.

Advantageously, according to this second production method, the distance between the intermediate rollers and the front rollers of the drafting train is greater than 45 mm, preferably, equal to or greater than 48 mm, in order to facilitate the insertion of the self-supporting piece.

The present invention also relates to a method for spinning fancy yarn such as that disclosed in patent WO20153381 1 , which can be implemented using the claimed machine that includes said device. In particular, the present invention provides a method for spinning fancy yarn that comprises the stages of:

a. feeding, simultaneously and in parallel, a bundle of effect fibres and a bundle of base fibres to the drafting train from a same spindle position of the machine, and b. alternately interrupting the feed of one or another bundle of fibres for the purpose of forming fancy yarn that combines different sections of effect fibres and base fibres, and is characterised in that the interruption of the feeding of one or another bundle of fibres of stage b) is carried out when said bundles of fibres are disposed on the support bed (L) of the fibre joining channel of the claimed device, an end of the bundle of fibres whose feed has been interrupted being susceptible of remaining on said support bed (L) and of waiting to be newly fed to the drafting train of the machine.

Due to the presence of the device and the self-supporting piece, the spinning process can be performed at high speed and without losing control of the fibres to obtain high-quality fancy yarn that alternately combines sections of base fibres and effect fibres. The processes of the state of the art require the use of pneumatic devices with air aspiration systems that entail high energy consumption.

Advantageously, the feeding of the bundle of effect fibres of stage a) is carried out when the bundle of effect fibres extends between a first set of drafting aprons associated with the rear rollers and with the intermediate rollers of the drafting train of the machine, and the feeding of the bundle of base fibres of stage a) is carried out when the bundle of base fibres extends between a second set of independent drafting aprons associated with the intermediate rollers of the same drafting train, said two sets of drafting aprons being susceptible of being fitted in the fitting arrangement envisaged on the obverse side of the self-supporting piece of the device.

In the present invention;

Fancy yarn shall be understood to be yarn formed from a bundle of base fibres and a bundle of effect fibres, said bundle of base fibres being, for example, a bundle selected from among natural, artificial or synthetic fibres, and said effect fibres being, for example, a bundle selected from among natural, artificial or synthetic fibres.

Brief description of the drawings

For a better understanding of that which is described herein, a set of drawings is attached which, schematically and solely by way of non-limiting example, represent various practical cases of embodiment.

Figure 1 shows a perspective view of the self-supporting piece of the device for joining fibres of the present invention showing the obverse side of this piece.

Figure 2 shows a perspective view of the self-supporting piece of the device for joining fibres of the present invention showing the reverse side of this piece.

Figure 3 shows a lateral view of the self-supporting piece of figures 1 and 2.

Figure 4 shows a perspective view of a drafting train of a machine for spinning fancy yarn that incorporates the self-supporting piece of the claimed device. For the sake of clarity, the figure does not include the pressure arm of the drafting train and the associated rollers. This figure 4 shows a machine having a processing and control unit configured to carry out a production method of fancy yarn wherein the feeding of the bundle of effect fibres and the bundle of base fibres is alternately interrupted to form yarn that combines alternating sections of effect fibres and base fibres.

Figure 5 shows a perspective view of a drafting train of a machine for spinning fancy yarn that incorporates the self-supporting piece of the claimed device. For the sake of clarity, the figure does not include the pressure arm of the drafting train and the associated rollers. This figure 5 shows a machine having a processing and control unit configured to carry out a production method of fancy yarn wherein a bundle of effect fibres is intermittently added to the bundle of base fibres.

Figure 6 shows a lateral view of the drafting train of a machine for spinning fancy yarn that incorporates the self-supporting piece of the claimed device. In this figure 6, the self- supporting piece is disposed in its work position.

Figure 7 shows a side view of the drafting train of a machine for spinning fancy yarn which incorporates the self-supporting piece of the claimed device. This figure 7 shows the pressure arm of the drafting train raised and the self-supporting piece disposed in an upper position abutting against the top bar of the drafting aprons.

Figure 8 shows a side view of the drafting train of the machine for spinning fancy yarn which incorporates the self-supporting piece of the claimed device. This figure 8 shows the pressure arm of the drafting train raised and the self-supporting piece completely extracted.

Figures 9 to 12 show three views of a second embodiment of the piece of the present invention that includes clips having fixation flaps.

Figure 13 shows a side view of the drafting train of a machine for spinning fancy yarn that includes the second embodiment of the self-supporting piece of figures 9 to 12 in the work position.

Description of preferred embodiments

Following is description of two embodiments of the device and two machines that include said device, making reference to figures 1 to 13.

Figures 4 and 5 show corresponding perspective views of the drafting train of two machines for spinning fancy yarn, each of which incorporate one self-supporting piece 1 of the claimed device. For the sake of clarity, the figures do not include the pressure arm of the drafting train and the associated rollers. Each of the machines is configured to carry out a different fancy yarn production method.

The drafting train of both machines includes three lines or pairs of rollers 2a, 2b, 2c wherebetween the bundles of effect fibres and base fibres pass. These three pairs of rollers 2a, 2b, 2c rotate at different increasing speeds to feed and draft one or more bundles of fibres in each spindle position. At the outlet of the last pair of front rollers 2c, the already drafted fibres are introduced in a torsion spindle (not represented).

The bottom rollers of each pair of rollers 2a, 2b, 2c are configured by cylinders which are mounted on trestles that likewise support a rod 4 whereon the pressure arms are mounted (an arm for each two spindle positions). These pressure arms have the function of positioning and securing the top rollers of the three lines of rollers (rear 2a, intermediate 2b and front 2c) under pressure on their respective bottom rollers.

As can be observed in figures 4 and 5, the drafting train also includes, for each spindle position, drafting aprons 6 that encircle the intermediate rollers 2b and are supported on a nose bar 7 of the drafting train itself.

The machine shown in figure 4 has the particularity that, in each spindle position, the intermediate rollers 2b are responsible for feeding a bundle 9 of effect fibres, while the rear rollers 2a are responsible for feeding a bundle of base fibres 8 that passes parallel to the bundle 9 of effect fibres, among independent drafting aprons 6. The feeding of the bundle 8 of base fibres and the bundle 9 of effect fibres is carried out in parallel when the rear rollers 2a and the intermediate rollers 2b are actuated by corresponding servomotors through a processing and control unit which is programmed to alternately interrupt the feeding of one or another bundle, 8, 9 for the purpose of forming fancy yarn that combines different sections of effect fibres and base fibres. As can be observed in figure 4, the bundle of base fibres 8 passes between first drafting aprons 6 associated with the rear rollers 2a and intermediate rollers 2b while the bundle 9 of effect fibres passes between second independent drafting aprons 6 associated solely with the intermediate rollers 2b.

As regards the machine shown in figure 5, it has the particularity that, in each spindle position, the intermediate rollers 2b are responsible for continuously feeding a bundle 8 of base fibres, while the rear rollers 2a are responsible for intermittently feeding a bundle of effect fibres that passes between the same drafting aprons 6. The feeding of the bundle 9 of effect fibres is carried out by intermittently injecting or adding a segment of the bundle 9 of effect fibres onto the bundle 8 of base fibres when the rear rollers 2a are actuated by a servomotor through a processing and control unit that is programmed for intermittently injecting the effect fibres into the base fibres.

Both the machine of figure 4 and the machine of figure 5 incorporate one self-supporting piece 1 having a fibre joining channel 10 which has been inserted between the front rollers 2c and the intermediate rollers 2b, at the outlet of the drafting aprons 6. As can be observed in figures 4 and 5, in their work position, the obverse side of the self-supporting piece 1 is centred and fitted against the drafting aprons 6 while the obverse side rests on the bottom front roller 2c.

Figures 1 to 3 show three views of a first embodiment of the self-supporting piece 1 , which is a one-piece made of plastic and having a very simple and reduced design.

The upper portion 1 a of the self-supporting piece 1 includes, on its obverse side, the entrance 10a of the fibre joining channel 10 and a support base configured by two projections 1 1 which, in the work position, rest on the nose bar 7 that secure the drafting aprons 6, on both sides of the drafting aprons 6 associated with said bar 7 (see figures 4 and 5). The reverse side of the same upper portion 1 a defines a surface 12 configured for adapting to the contour of the top front roller 2c. As can be observed in figure 2, this surface 12 includes the exit 10b of the fibre joining channel 10.

The lower portion 1 b of the self-supporting piece 1 extends from the upper portion 1 a to occupy, in a work position, a free space "e" between the bottom front roller 2c and the bottom intermediate roller 2b. The obverse side of this lower portion 1 b includes a fitting arrangement 13 dimensioned to fit the piece 1 against the drafting aprons 6 associated with the bar 7 that secures them (see figure 1 ). This fitting arrangement 13 allows the fibre joining channel 10 to be disposed in a suitable position for receiving the fibres that come out of drafting in a secure and controlled manner and for guiding said fibres towards the exit 10b of the same channel 10. The reverse side of the lower portion 1 b of the piece 1 defines the curved support surface 14 that rests on the bottom front roller 2c, as well as recesses 15 made on both sides of this support surface 14 for facilitating the output of the fibres that accumulate between the bottom front roller 2c and the said support surface 14 (see figure 2).

Figure 3 shows a side view of the self-supporting piece 1 wherein the extension and thickness of the lower portion 1 b of the piece 1 can be observed. In the work position, this lower portion 1 b is inserted in a free space "e" between the front rollers 2c and the intermediate rollers 2b (see figure 8).

In the embodiment described, the lower portion 1 b of the piece has been dimensioned to abut against the nose bar 7 when the pressure arm 5 rises and the piece 1 moves to an upper position actuated by the bottom front roller 2c (see figure 7). In this manner, the piece 1 does not escape from its position when the pressure arm 5 rises to perform, for example, a maintenance operation. The same piece 1 can be moved to its work position again when the arm 5 descends and comes into contact with the edge of the upper portion 1 a of the same piece 1 . If necessary, the piece 1 can be fully extracted (see figure 8).

Optionally, according to a second embodiment of the piece 1 , this piece 1 has clips 17, each of which has a fixation flap 18 capable of being inserted under pressure beneath the nose bar 7 for securing the drafting aprons 6 when the piece 1 is fitted against the drafting aprons 6 (see figures 9 to 13).

Therefore, when the pressure arm 5 rises, the piece 1 does not move and the fixation flap 18 must be forced out from under the nose bar 7 of the drafting aprons in order to remove the piece 1 .

Figures 9 to 12 show the details of this second embodiment of the piece 1 with the two side clips 17 having the fixation flaps 18 and tongues 19 for forcing the exit of the flaps 18 when the piece 1 must be removed.

Following is a description of the operation of the device and of the two machines that include the device and which are configured to produce fancy yarn according to two different production methods.

As mentioned earlier, in the machine of figure 4, the feeding of the bundle 8 of base fibres and the bundle 9 of effect fibres is carried out simultaneously and in parallel while said bundles 8, 9 of fibres pass between two sets of independent drafting aprons associated with the same spindle position. The entrance 10a of the fibre joining channel 10 of the self-supporting piece 1 is dimensioned to receive in parallel two bundles 8, 9 of fibres on a same support bed "L".

The process carried out by the machine represented in figure 4 is characterised in that the interruption of the feeding of one or another bundle of fibres is carried out when said bundles 8, 9 of fibres are disposed on the support bed "L", such that the end of the bundle whose feeding is interrupted may be disposed, after the cutting or separation of the fibres, on said support bed "L", waiting to be newly fed. The bundle that continues to be fed penetrates walls 16 that envelop the fibre joining channel 10 of the fibres that converge in the exit 10b envisaged on the reverse side of the upper portion 1 a of the self-supporting piece 1 , in order to be positioned between the front rollers 2c before entering the torsion spindle.

Due to the presence of the self-supporting piece 1 , the spinning process carried out by the machine of figure 4 may be performed at high speed and without losing control of the fibres to obtain high-quality fancy yarn that alternately combines sections of base fibres and effect fibres. The processes of the state of the art that manufacture this type of yarn require the use of pneumatic devices having sophisticated air aspiration systems that entail high energy consumption.

As regards the machine of figure 5, it is configured to produce fancy yarn that includes segments of effect fibres added onto the base fibres. As mentioned earlier, in this machine the bundle 8 of base fibres is fed continuously on passing said bundle 8 of base fibres between the drafting aprons 6 associated with the intermediate rollers 2b. The addition of the effect fibres occurs on intermittently injecting a segment of the bundle 9 of effect fibres onto the bundle 8 of base fibres when a servomotor actuates the rear rollers 2a.

In the machine represented in figure 5, the entrance 10a of the fibre joining channel 10 of the self-supporting piece 1 receives and supports, in this case, a single bundle of fibres that intermittently incorporates the addition of effect fibres. However, in this case, the enveloping walls 16 of the channel 10 also guarantee the cohesion of all the effect fibres and base fibres and their compaction up to the exit 10b envisaged on the surface 12 of the obverse side of the piece 1 disposed underneath the top front roller 2c.

Due to the presence of the self-supporting piece 1 , the spinning process carried out by the machine of figure 5 may also be carried out at high speed, without losing control of the fibres, to obtain high-quality fancy yarn.

Surprisingly, the claimed device and, in particular, the self-supporting piece 1 of this device, makes it possible to adapt the spinning machines to any type of production of fancy yarn in a simple and inexpensive manner.

Despite the fact that reference has been made to a specific embodiment of the invention, it is evident for a person skilled in the art that the described device and process is susceptible to many variations and changes, and that all the aforementioned details may be replaced by other technically equivalent ones, without detracting from the scope of protection defined for the attached claims.