WO2016058987A1

WO2016058987A1 - Machine and method for the production of fancy yarns

Info

Publication number: WO2016058987A1
Application number: PCT/EP2015/073558
Authority: WO
Inventors: Davide Maccabruni; Roberto BADI; Antonio RIPAMONTI
Original assignee: SSM Giudici SRL
Current assignee: SSM Giudici SRL
Priority date: 2014-10-13
Filing date: 2015-10-12
Publication date: 2016-04-21
Anticipated expiration: 2017-04-13
Also published as: TW201623713A

Abstract

Machine for the production of a composite yarn (F) having a core yarn (FC), an effect yarn (FE) and an elastomer yarn (FL) combined together comprising: a core yarn feeding path; an effect yarn feeding path and an elastomer yarn feeding path. The machine further comprises a texturing and interlacing jet (51), where the paths of the core yarn (FC), the effect yarn (FE) and the elastomer yarn (FL) converge. The texturing and interlacing jet is configured and arranged to join together, in a single operation, the core yarn, the effect yarn and the elastomer yarn.

Description

MACHINE AND METHOD FOR THE PRODUCTION OF FANCY YARNS

DESCRIPTION

Technical field

The present invention relates to the field of threads and yarns production, particularly synthetic threads and yarns. In greater detail, the present invention relates to the production of so-called composite yarns, in which a core yarn, an effect yarn and an elastomer yarn are combined together to obtain a composite yarn destined for production of textile articles for apparel, furnishing, automotive industry and for other applications.

Background Art

In the textile industry, for producing various types of textiles, in both the field of apparel and furnishing, as well as in the automotive industry, for the creation of upholstery of the interior of motor vehicles, or similar, so-called composite or fancy yarns are frequently used. These yarns are obtained by combining at least one core yarn and at least one effect yarn. The core yarn and the effect yarn both normally comprise a plurality of fibres or so-called filaments produced by extrusion of a molten polymer. The combination of the core yarn and effect yarn may take place in a false-twist texturing process, wherein the threads are individually subjected to a false twisting and heating step, so as to induce, by means of a mechanical and thermal effect, curling in the filaments forming the two yarns. Subsequently, the core yarn and the effect yarn are combined to obtain the fancy yarn. The effect yarn is arranged mainly around the core yarn. The drawing, heating and false twisting process is usually called texturing.

An alternative method for the production of fancy yarn provides for the combination of a core yarn and an effect yarn without heating and false twisting, but rather by means of an air jet. In this case, reference is made to air or air-jet texturing (so-called "Taslanizing").

An example of an air texturing machine is described in EP 1544333. In these air texturing machines, at least one effect yarn and at least one core yarn are combined by means of a high-speed air jet which curls the filaments forming the two yarns. For this purpose, the two yarns are fed through an air jet. The effect yarn is normally fed at a higher speed than the core yarn, so that the filaments of the effect yarn are mainly arranged outside the core yarn and around it. The textured yarn is used in certain cases as a coating yarn of an elastomer yarn or elastomer, for example Lycra®. In some known embodiments, coating of the elastomer yarn with the fancy yarn obtained by combining the effect yarn and the core yarn is obtained in a further, so-called interlacing jet. The fancy yarn coats the elastomer yarn to obtain a composite yarn, by means of which textile articles are manufactured.

Interlacing of the elastomer yarn and the effect yarn normally takes place in a separate machine with respect to the texturing machine, whether this is an air texturing machine or a false twisting and heating texturing machine. In certain cases, particularly in false twist texturing machines, the combination of textured yarn and elastomer yarn takes place in the same machine performing false twisting and heating, but in a separate station, arranged downstream of the texturing elements along a yarn feeding path.

EP-A-0161572 describes a method for producing a composite yarn, wherein three yarns are fed into an interlacing jet. The first yarn is fed from a spool and is formed of a yarn previously subjected to a false-twist texturing process upstream and by means of a different machine. The second yarn is a yarn obtained, also in a process upstream, from spinning of cut fibres. The third yarn is an elastomer yarn. In the interlacing jet, the three yarns are simply combined by means of an air current, without further processing.

WO- A-88/09403 describes a method and a machine for the production of a yarn, particularly a sewing thread. The thread is formed of at least two yarns bonded with each other by means of a third adhesive yarn. No texturing is provided in this case.

WO-A-2013164791 describes a method and a machine for manufacturing a composite yarn. A yarn is unwound from a first spool and subjected to texturing by passing through an oven and subsequently passing through a false twist spindle. The yarn thus treated is fed into an interlacing jet, where it is combined with an elastomer yarn and a third non-elastic yarn, coming from respective spools. The third yarn is a yarn previously subjected to an air texturing treatment, in a separate machine.

US-A-4,615,167 describes a method for manufacturing a fancy yarn by bonding one or more effect yarns and a core yarn by means of an interlacing jet. Use of an elastic yarn is not provided. EP-A-0269184 describes a machine for manufacturing a composite yarn by means of air interlacing. The machine provides for a single path for a non-elastic yarn and a single path for an elastic or elastomer yarn. The two yarns are unwound from two respective spools and fed through an interlacing jet. The interlacing jet is configured and arranged for bonding the non-elastic yarn to the elastic yarn. The composite yarn thus obtained is collected on a spool. This known machine does not provide for any further yarn paths, besides the two mentioned, and also does not provide for any type of texturing treatment.

The operations involved in manufacturing fancy yarn or composite yarn containing elastomer and coating yarn are complex, difficult to manage and costly.

There is therefore a need for a simpler and less expensive machine for manufacturing composite yarns. There is also a need for new manufacturing methods, which entirely or partly overcome the drawbacks of the above described known methods.

Summary of the Invention

According to a first aspect, a machine is described for the production of a composite yarn comprised of a core yarn, an effect yarn and an elastomer yarn combined together, comprising a core yarn feeding path, an effect yarn feeding path, and an elastomer yarn feeding path. The machine furthermore comprises a texturing and interlacing jet, where the core yarn path, the effect yarn path and the elastomer yarn path, separate from one another, i.e. before being joined together, converge. The texturing and interlacing jet is configured and arranged to join together, in a single operation, the core yarn, the effect yarn and the elastomer yarn. Furthermore, the jet performs a texturing process on the yarns fed therethrough.

An air texturing and interlacing process of the effect yarn and the core yarn with the elastomer yarn in a single texturing and interlacing jet, and therefore with a single operation, is thus obtained. The machine is more compact, more economical and easier to control than the existing machines.

It must be noted that the interlacing and texturing jet has a shape, known per se, which is different with respect to simple interlacing jets, which do not perform any type of texturing on the yarn. According to the invention, by using an interlacing and texturing jet, rather than a simple interlacing jet, it is possible to perform several processes on the yarns moving through the jet, thus obtaining a more compact procedure and a smaller, less expensive and more productive machine. It is not necessary to provide texturing systems, such as false twisting, in the path upstream of the texturing and interlacing jet. Nor is it necessary to use yarns which have already been subjected, in a previous step, to a texturing process.

A single or multiple oven may be provided upstream of the texturing and interlacing jet, through which oven the effect yarn path and the core yarn path pass, before being fed through the texturing and interlacing jet.

In some embodiments, the machine also comprises a wetting head upstream of the texturing and interlacing jet. The wetting head may be arranged, with respect to the path of the yarns, in a manner that the core yarn passes through the wetting head, while the other yarns do not. In other embodiments, the elastomer yarn and/or the effect yarn may also pass through the wetting head.

In advantageous embodiments, the machine may comprise a godet arranged between the texturing and interlacing jet and a winding unit for winding the composite yarn. The composite yarn exiting the texturing and interlacing jet is driven around the godet. In some embodiments the godet is heated.

The machine may comprise one or more ovens. The path of the effect yarn and the pass of the core yarn pass through the oven, or through two distinct ovens.

Along the effect yarn path and/or the core yarn path respective drawing devices may be arranged, for instance pairs of rollers. In some embodiments, the drawing devices are configured and controlled so as to draw the core yarn and the effect yarn at different drawing ratios.

In some embodiments, the drawing devices are arranged so that the yarn is drawn in a portion which comprises the path through the oven.

According to a further aspect, a method is provided for the production of a composite yarn having a core yarn, an effect yarn and an elastomer yarn combined together, comprising the steps of:

- feeding the, preferably non-textured, effect yarn along an effect yarn feeding path;

- feeding the, preferably non-textured, core yarn along a core yarn feeding path;

- feeding the elastomer yarn along a feeding path for the elastomer yarn;

- conveying the elastomer yarn, the core and the effect yarn, separated from one another, into a texturing and interlacing jet;

- texturing the core and the effect yarn and joining the elastomer yarn, the core yarn and the effect yarn together by means of the texturing and interlacing jet. According to advantageous embodiments, the effect yarn and the core yarn may be heated in an oven along their respective feeding paths. One single oven may be used for both the yarns, or two different ovens can be provided.

Features and embodiments are disclosed here below and are further set forth in the appended claims, which form an integral part of the present description. The above brief description sets forth features of the various embodiments of the present invention in order that the detailed description that follows may be better understood and in order that the present contributions to the art may be better appreciated. There are, of course, other features of the invention that will be described hereinafter and which will be set forth in the appended claims. In this respect, before explaining several embodiments of the invention in details, it is understood that the various embodiments of the invention are not limited in their application to the details of the construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

As such, those skilled in the art will appreciate that the conception, upon which the disclosure is based, may readily be utilized as a basis for designing other structures, methods, and/or systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.

Brief description of the drawings

The invention will be better understood by following the description and accompanying drawing, which shows non- limiting practical embodiments of the invention. More particularly, in the drawing:

Fig. 1 shows a section according to a vertical plane of a working front of a machine comprising a plurality of stations or positions for the manufacture of composite yarns; Fig. 2 shows an enlargement of the conveying zone of the yarns through the box containing the texturing and interlacing jet;

Fig. 3 shows a section of the box containing the texturing and interlacing jet; Fig. 4 shows a schematic section of a texturing and interlacing jet;

Fig. 5 shows a similar section to Fig. 1 in a different embodiment.

Detailed description of embodiments

The following detailed description of exemplary embodiments refers to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. Additionally, the drawings are not necessarily drawn to scale. Also, the following detailed description does not limit the invention. Instead, the scope of the invention is defined by the appended claims.

Reference throughout the specification to "one embodiment" or "an embodiment" or "some embodiments" means that the particular feature, structure or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrase "in one embodiment" or "in an embodiment" or "in some embodiments" in various places throughout the specification is not necessarily referring to the same embodiment(s). Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

Fig. 1 shows a section according to a vertical plane of a working front of a machine, denoted in its entirety with number 1, comprising a plurality of working units or positions 2, equal to each other and arranged according to one front or two opposite fronts. Fig. 1 shows a half-section of the machine 1, the other half being substantially symmetrical with respect to a vertical plane A-A. In other embodiments the machine 1 may have a single front of working units or positions 2.

The machine 1 is associated with one or more creels 3, on which yarn spools BC, BE are arranged. The spools BC and BE may be identical or different to each other, for example they may contain yarns of different types. Fig. 1 shows only a portion of the creel 3, which may have a large number of supports 5 for corresponding number of spools BC, BE. One creel may contain spools BC, BE to feed one or more work units 2 of the machine 1.

In other embodiments, between the creel 3 and the front on which the work units 2 are aligned, a passage 7 may be provided for the operator O, who thus has access to the various work positions 2. Above passage 7, a supporting structure 9 may extend, to which elements may be connected which define, for each work unit or position 2, a feeding path for a core yarn and a feeding path for an effect yarn, coming from spools BC, BE of the creel 3.

In the embodiment shown in Figs. 1 and 2, one or more ovens 11 are associated with the structure 9, through which the effect yarn path and the core yarn path coming from spools BE, BC of creel 3 pass. In some embodiments, at each work position or unit 2, a core yarn FC and an effect yarn FE are fed along two feeding paths which may coincide with each other in part. In the embodiment show, the core yarn FC and the effect yarn FE are fed towards the work position or unit 2 through a single oven 11, which may be accompanied by inlet guide elements 11A and outlet guide elements 1 IB for yarns FC and FE respectively. A single oven may be sized for passage of several pairs of yarns FC and FE destined for several work units or work positions 2 of the front of the machine 1. In other embodiments, separate ovens may be provided for each pair of yarns FC, FE destined for a single work unit or position 2.

The core and effect yarns may be, for example, polyamide 6 yarns, polyamide 66 yarns, polyester yarns or other yarns suited to the processes being described herein.

In some embodiments, each work position 2 comprises a box 13, in which the elements are housed, that perform air texturing and interlacing of the core yarn FC, the effect yarn FE and an elastomer yarn FL. The elastomer yarn comes from a spool BL. In the embodiment shown (see, in particular, Fig. 2), the spool BL of elastomer yarn FL is placed close to the box 13. The spool BL may also be placed more distant from box 13. The texturing and interlacing elements contained in the box 13 will be described below with specific reference to Fig. 3 and Fig. 4.

In some embodiments, a box 13 may contain several texturing and interlacing elements for several work positions.

In some embodiments, the path of the core yarn FC coming from spools BC may extend along a guide element 15 and a pair of rollers 17, 18 pressed against each other, of which at least one is motorised, arranged upstream of the inlet 11 A of the furnace 11.

Downstream of outlet 11B of the oven 11, the path of the core yarn FC continues through a nip defined between a further pair of rollers 19, 20, pressed against each other, at least one of which is motorised. From the nip defined between the rollers 19, 20, the path of the core yarn FC extends as far as the box 13, into which the core yarn FC enters by passing through a guide element, for example a ceramic, schematically indicated with number 21 in Fig. 3.

In a known way, the rollers 17, 18 draw the yarn FC coming from one of the spools BC positioned on the creel 3 and feed the yarn towards the oven 11 at a speed corresponding to a peripheral speed of the rollers 17, 18. The rotation speed of the rollers 17, 18 may be variable and controllable.

The rollers of the pair of rollers 19, 20 also have a peripheral speed which may be variable and controllable. In embodiments of the machine described herein, the peripheral speed of the rollers 19, 20 is higher than the peripheral speed of the rollers 17, 18, so that the core yarn FC is drawn in the section between rollers 17, 18 and rollers 19, 20. The oven 11 heats the yarn FC in the zone in which it is drawn as a result of said difference in peripheral speed between rollers 17, 18 and 19, 20.

The path of the effect yarn FE extends along the guide element 15, or along another guide element separate from the guide element 15, and through a nip defined by a pair of rollers 23, 24, at least one of which is motorised. The rollers 23, 24 are upstream of the inlet 11 A of the furnace 11.

Downstream of the outlet 11B of the furnace 11, a further pair of rollers 25, 26 may be provided, at least one of which is motorised. Downstream of the rollers 25, 26, the path of the yarn FE continues as far as the box 13. A further guide element 29 is associated with the latter, for example a ceramic, through which the path of the effect yarn FE extends and thus penetrates inside the box 13.

Similarly to what has been indicated for rollers 17, 18 and 19, 20, rollers 23, 24 may also have peripheral speed different from the speed of rollers 25, 26 and the two pairs of rollers 23, 24 and 25, 26 may have a variable and controllable speed.

In order to obtain the degree of drawing required for the two yarns FE, FC, the rollers 25, 26 preferably have a peripheral speed higher than that of rollers 23, 24. In this way, the effect yarn FE is subjected to drawing between the pair of rollers 25, 26 and the pair of rollers 23, 24, and particularly in the section of the path of yarn FE which extend through the oven 11 that therefore heats the section of yarn FE being drawn. The difference between the peripheral speeds of rollers 23, 24 and 25, 26 may be equal to the difference between the peripheral speeds of rollers 17, 18 and 19, 20. In general, however, the two differences in speed, which define the degree of drawing imparted to the two yarns FE and FC, may be differ from one other, so that the two yams FE and FC are subjected to different drawing percentages. For example, the effect yarn FE may be subjected to a higher degree of drawing.

The amount of drawing, i.e. the lengthening percentage imposed on the yarns FE and FC may depend upon the final characteristics which it is intended to obtain and/or the characteristics of the source yarns, wound around spools BE and BC. The source yams, in this case are usually the so-called POY (Partially Oriented Yarns). The drawing to which they are subjected completes orienting of the yarns, i.e. changes the molecular structure of the polymer forming them. The effect yarn FE is usually subjected to a higher degree of drawing, i.e. it is lengthened more than the core yarn FC.

If the yam used is a Fully Drawn Yarn (FDY), it is possible to avoid use of the oven 11, i.e. keep it switched or at low temperature. Furthermore, the pairs of rollers arranged along the path of said yam may rotate at the same peripheral speed, in a manner not to draw the yam.

In some embodiments, it is possible to use the oven also in combination with use of an FDY. In some embodiments, it is possible to apply a minimum drawing percentage, for example 0.2%. Passage of the FDY in the oven may provide advantages in the interlacing step.

In the embodiment shown, with particular reference to Figs. 1 and 2, the spool BL of the elastomer yam FL is supported in a position which is very close to the box 13, and, in any case, closer to said box 13 than the position of the spools BE and BC of effect yam FE and core yam FC, respectively. While the latter, in fact, re fed along paths which extend around the passage 7 of the operator and along which the drawing and thermal stabilisation elements, formed by the pairs of rollers 17, 18; 19, 20; 23, 24 e 25, 26 and also the oven 11, are arranged, the spool of the elastomer yam FL is as close as possible to the entrance of the box 13. The latter has a third guide element 31 , for example a ceramic, for passage of the elastomer yam FL inside the box 13.

It is also possible to arrange the spool BL of elastomer yam FL at a greater distance from the box 13, for example above the structure 9, beneath it and above path 7, or even on the creel 3. However, arrangement of the spool BL of elastomer yam FL close to the box 13 allows more regular functioning and better control of the tension of the elastomer yarn FL to be obtained. In some embodiments, the spool BL may be carried by an arm 33 which allows movement thereof to replace the empty spool with a new spool. In the position where the spool BL of elastomer yarn FL is arranged, it is possible to provide a roller 35 which presses against the outer cylindrical surface of the spool BL. In this way, rotation of the suitably motorised roller 35 may control unwinding of the spool BL and feeding of the elastomer yarn FL towards and inside the box 13.

Inside the box 13, the three yarns FC, FE and FL are combined in the way and with the elements which will be described below with specific reference to Fig. 3, to obtain, at the exit side of the box 13, and in any work position 2 of the machine 1, a composite yarn F. This latter is fed to a respective collection zone 37 to form a bobbin or spool B by means of a winding system which may comprise a motorised roller 39 and a distribution device 41, all as known per se to those skilled in the art.

In the embodiment shown, along the front on which the work positions 2 are arranged, the machine 1 has a plurality of positions 37 for collecting and winding the composite yarn F superimposed on each other. In the example shown, the collecting positions 37 are arranged on three superimposed levels, to reduce the total dimensions of the machine 1 and the length of the front along which the work positions 2 are arranged. It is also possible to arrange superimposed on each other a number of collection positions greater than or less than three or even arrange the collection positions 37 all at the same height, rather than superimposed on each other.

The collecting system of the composite yarn F on the spool B may be configured, for example, as described in US 7426820, the content whereof is incorporated herein by reference, or in any other opportune way.

Fig. 3 shows a possible embodiment of the elements contained inside the box

13. In preferred embodiments, the box 13 contains a texturing and interlacing jet 51, where the paths of the core yarn FC, effect yarn FE and elastomer yarn FL converge. The texturing and interlacing jet 51, the configuration of which may be as shown in Fig. 4 and better described below, by means of jets of pressurised air, performs a dual function on the three yarns FC, FE and FL, namely of texturing the core yarn FC and the effect yarn FE and interlacing them on and around the elastomer yarn FL.

At the exit side of the interlacing jet 51, a composite yarn F is therefore obtained, which may come out of the box 13 through a guide element 53, for example a ceramic, to be fed towards the corresponding collecting position 37. As shown in particular in Fig. 1, downstream of the box 13, a godet 55 may also be arranged, around which the yarn F is wound to form a plurality of turns. The godet 55 may be heated or may serve to stabilise the composite yarn F before it is collected on the corresponding spool B. If superimposed collecting positions 37 are provided under the box 13, several godets 55 arranged side by side may be provided in the direction of extension of the front of the machine, one for each collecting unit 37. Only one of the godets 55 is visible in Fig. 1.

A single texturing and interlacing jet may be arranged in a single box 13. In this case, one box 13 will be provided for each work unit or position 2. It is also possible to arrange several texturing and interlacing jets 51, relating to several work positions or units 2, in the same box 13.

With reference to Fig. 4, the main component of the texturing and interlacing jet 51 is a conduit 53, which has an inlet 53 A and an outlet 53B. The inlet 53 A is turned towards the entry zone of the yarns FL, FC and FE. The latter are guided inside the conduit 53 in the zone with a gradually decreasing transversal section, which extends from the inlet 53 A as far as an intermediate zone 55 of the texturing and interlacing jet 51. In this intermediate zone 55, where the conduit 53 may have an approximately constant cross section, air jets are channelled through entry ports 57, variable in number, and arranged around an axis X-X, along which the conduit 53 extends. The end section of the conduit 53, towards the outlet 53B, has a gradually increasing cross section. In the conduit 53 thus shaped, as a result of the compressed air which is injected through ports 57, the three yarns FL, FC e FE are bonded with each other to form the composite yarn F. In the texturing and interlacing jet 51 , there are therefore combined texturing actions of the yarns FC, FE and interlacing actions of said yarns with the elastomer yarn FL.

The configuration of the texturing and interlacing jet 51 shown in Fig. 4 is solely an example, since other embodiments are possible, as a function, for example, of the production speed, the dimensions of the yarns used, the number of filaments thereof, etc.

The texturing and interlacing jet may be designed, for example, as described in US7,752,723 or in EP1.541.727, the content whereof is incorporated herein by refernce.

In some embodiments, between the guide elements 21, 31 and 29 of the yarns FC, FL and FE and the inlet of the texturing and interlacing jet 51, a wetting head 61 may be arranged, whereto water or another suitable liquid is supplied, to wet one or more of the yarns FC, FL, FE which are fed into the texturing and interlacing box 13. In other embodiments, the wetting head 61 may be omitted.

In the embodiment shown, the wetting head 61 is supported by means of a rod 63 on the upper wall 13S of the box 13. A conduit, not shown, may be connected to a coupling 65 to supply water inside the wetting head 61 and, in more detail, into a slot 6 IF through which one or more yarns FE, FC, FL may be fed.

In the embodiment shown, only the core yarn FC is fed through the wetting head 61 along the slot 6 IF to be wetted by the water supplied to the wetting head 61. In other embodiments, the effect yarn, together with the core yarn FC, or only the effect yarn FE, may also be fed into the slot 61F.

Preferably, the elastomer yarn FL is not passed into the wetting head 61. In the embodiment shown in Fig. 3, the elastomer yarn FL is guided outside the wetting head 61 along a path which is as close as possible to the path of the core yarn FC which, vice versa, pass through the wetting head 61. In some embodiments, for this purpose the elastomer yarn FL may be guided by a guide element 69, for example a ceramic. The latter may have an open U-shaped section to facilitate entry of the elastomer yarn FL by laterally approaching the guide element 69.

The effect yarn FE may move along a path which is slightly distant with respect to the wetting head 61 and, in this possible embodiment, is therefore not guided along any guide element fixed to or on the wetting head 61.

With the machine described so far, it is possible to manufacture a composite yarn F comprising a core yarn FC, an effect yarn FE and an elastomer yarn FL coated by means of a texture yarn obtained by combination of yarns FC and FE. By combining the three yarns FC, FE and FL in a single texturing and interlacing jet 51 a substantial simplification of the machine is obtained, with a lower number of yarn guide elements, a shorter path of the yarns and lower overall dimensions of the machine. Furthermore, using a single texturing and interlacing jet, compressed air consumption is reduced, with a consequent and substantial saving of energy and also reduce of machine noise. Regulation of the machine may also be simplified, thanks to the presence of a lower number of yarn passage elements.

As already mentioned, the core yarn FC and effect yarn FE may be so-called POY (Partially Oriented Yarns) or so-called FDY (Fully Drawn Yarns). In the first case, the FC and FE yarns are preferably drawn along the path by the creel 3 as far as the box 13 and, more precisely, between the pairs of rollers 17, 18 and 19, 20 as far as concerns the core yarn FC and between the rollers 23, 24 and 25, 26 as far as concerns the effect yarn FE. As already mentioned, the drawing percentage for the two yarns may be the same, or different, thanks to the fact that the feeding and drawing rollers are independent for the two paths of yarns FC and FE, respectively. In general terms, yarns FC and FE may be, at the start, the same or different to each other. Their structure is, in any case, changed as a result of drawing and possibly heating by means of the oven 11 , so that, when exiting the pairs of drawing rollers 19, 20 and 25, 26, respectively, the two yarns FE and FC will normally have features which are partially different from one another. It is also possible to apply the same drawing percentage to both yarns FE and FC thereby obtaining identical yarns.

In some embodiments, the core yarn FC and the effect FE may be drawn with the same drawing percentage and then fed to the subsequent texturing and interlacing step with different overfeed percentages.

However, in general, the effect yarn FE is fed to the texturing and interlacing jet at a speed higher than the speed of the other yarns, i.e. at a greater overfeed, so as to be arranged more on the external part of the of the final composite yarn F, forming a coating.

In some embodiments, a double oven 11 may be provided, one for the effect yarn FE and the other for the core yarn FC. In this way, it is possible to regulate the temperature, at which the yarn being drawn is stabilised, differently for yarns FE and FC. However, in preferred embodiments, as shown in the figure, the oven 11 may be single and its temperature may be regulated at a compromise value suitable for both yarns FC, FE, even when these are different in nature and/or subjected to different drawing percentages.

When yarn FC and/or yarn FE is a Fully Drawn Yarn (FDY), it does not require any further drawing and therefore the peripheral speeds of the feeding and drawing rollers 17, 18; 19, 20; 23, 24 and 25, 26 may be regulated accordingly, so that along the respective section of the path of yarn FE and/or FC the yarn itself is not drawn further. The oven 11 may be deactivated.

In other embodiments, as schematically shown in Fig. 5, when use of the oven 11 and drawing of the core and effect yarns is not necessary, the machine may have a simplified structure, where the effect FE and core FC yarns coming from the creel 3 are fed directly by means of the feeding units to the box 13. In Fig. 5, the same numbers indicate the same or equivalent parts to those described with reference to Fig. 1.

In the embodiment shown in Fig. 5, no ovens 11 are mounted on the supporting structure 11. The paths of yarns FE and FC coming from the creel 3 extend along a guide element 15 and along a further guide element 16, towards a pair of feeding rollers 17, 18 for the core yarn FC and a pair of feeding rollers 23, 24 for the effect yarn FE. From these pairs of rollers 17, 18 and 23, 24, the core yarn FC and effect yarn FE are fed directly to the inlet of the box 13. The elastomer yarn FL coming from the spool BL, preferably arranged in a winding unit positioned also in this case adjacent to the box 13, is fed into the box 13, but it shall be understood (as already indicated with reference to Fig. 1) that the winding unit of the spool BL of the elastomer yarn FL could also be on the side of the creel 3.

Downstream of the box 13, equivalent or identical elements to those described with reference to Fig.l are also arranged.

The embodiments described above and illustrated in the drawings have been explained in detail as examples of embodiment of the invention. It will be clearly apparent to those skilled in the art that modifications, variants, additions and omissions are possible, without however departing from the principles, the scope of the concept and the teachings of the present invention as defined in the attached claims. The scope of the invention shall be therefore determined exclusively based upon the widest interpretation of the attached claims, wherein these modifications, variants, additions and omissions are included within this scope. The terms "comprising" "to comprise" and the like do not exclude the presence of further elements or steps in addition to those specifically listed in a claim. The term "a" or "an" before an element, means or feature of a claim does not exclude the presence of a plurality of these elements, means or features. If a claim of a device claims a plurality of "means", some or all these "means" can be actuated by a single component, member or structure. The enunciation of given elements, features or means in distinct depending claims does not exclude the possibility of combining said elements, features or means together. When a method claim lists a sequence of steps, the sequence with which these steps are listed is not binding and can be changed, if the particular sequence is not indicated as binding. Any reference numerals in the appended claims are provided to facilitate reading of the claims with reference to the description and to the drawing, and do not limit the scope of protection represented by the claims.

Claims

1. A machine for the production of a composite yarn having a core or ground, an effect yarn and an elastomer yarn combined together, comprising:

a core yarn feeding path;

an effect yarn feeding path;

an elastomer yarn feeding path;

a texturing and interlacing jet, where the core yarn feeding path, the effect yarn feeding path and the elastomer yarn feeding path converge; the texturing and interlacing jet being designed and arranged to join together, in a single operation, the core yarn, the effect yarn and the elastomer yarn.

2. The machine of claim 1, wherein at least one oven is arranged along at least one of the effect yarn feeding path and the core yarn feeding path.

3. Machine according to claim 1 or 2, comprising a wetting head upstream of the texturing and interlacing jet, wherein the core yarn feeding path passes through said wetting head.

4. Machine according to claim 3, wherein the elastomer yarn feeding path comprises a guiding element adjacent to the wetting head, so that the elastomer yarn moves along a path segment adjacent to the wetting yarn but outside thereof.

5. Machine according to one or more of the previous claims, comprising a box, inside which the texturing and interlacing jet is arranged, and wherein three separate guiding elements are associated with the box, said guiding elements arranged along the core yarn feeding path, along the effect yarn feeding path and along the elastomer yarn feeding path.

6. Machine according to one or more of the previous claims, comprising a godet arranged between the texturing and interlacing jet and a collecting unit for collecting the composite yarn, the composite yarn exiting from the texturing and interlacing jet being driven around said godet.

7. A machine according to claim 6, wherein said godet is heated.

8. Machine according to one or more of the previous claims, wherein the core yarn feeding path and the elastomer yarn feeding path have at least one substantially matching portion.

9. Machine according to at least claim 2, wherein along the effect yarn feeding path and the core yarn feeding path respective drawing devices are arranged, to draw the yarn between a point upstream of the oven and a point downstream of the oven.

10. Machine according to one or more of the previous claims, comprising an unwinding unit to unwind a reel of elastomer yarn, the unit being adjacent to the texturing and interlacing jet.

11. A method for the production of a composite yarn having a core yarn, an effect yarn and an elastomer yarn combined together, comprising the steps of: feeding the effect yarn along an effect yarn feeding path;

feeding the core yarn along a core yarn feeding path;

feeding the elastomer yarn along an elastomer yarn feeding path ;

conveying the elastomer yarn, the core yarn and the effect yarn, separated from one another, into a texturing and interlacing jet;

texturing the core yarn and the effect yarn and joining the elastomer yarn, the core yarn and the effect yarn together by means of the texturing and interlacing jet.

12. The method of claim 11, wherein the effect yarn fed along the effect yarn feeding path is a non-textured effect yarn.

13. The method of claim 11 or 12, wherein the core yarn fed along the core yarn feeding path is a non-textured core yarn.

14. The method of claim 11, 12 or 13, comprising the step of heating the core yarn along the core yarn feeding path.

15. The method of one or more of claims 1 1 to 14, comprising the step of heating the effect yarn along the effect yarn feeding path.

16. Method according to one or more of claims 11 to 15, wherein the core yarn is wet before being inserted into the texturing and interlacing jet.

17. Method according to claim 16, wherein the core yarn passes through a wetting head, while the effect yarn and the elastomer yam pass outside the wetting head.

18. Method according to one or more of claims 11 to 17, comprising the step of drawing at least one of the effect yam and the core yam between respective reels, wherefrom they are unwound, and the texturing and interlacing jet.

19. Method according to claim 18, wherein at least one of the effect yam and the core yam is drawn along a path portion between a point upstream of an oven and a point downstream of an oven.

20. Method according to claim 18 or 19, wherein the effect yam and the core yam are drawn at different drawing ratios from each other.

21. Method according to claim 20, wherein the core yam is drawn at a lower drawing percentage than the effect yam.

22. Method according to one or more of claims 18 to 21, wherein the core yam is drawn and then wetted before being fed into the texturing and interlacing jet.

23. Method according to one or more of claims 11 to 22, wherein at least one of the core yam and the effect yam is tensioned upstream of the texturing and interlacing jet, the core yam being preferably subjected to a higher tension than the effect yam.