METHOD FOR SPINNING FANCY YARNS, MACHINE FOR SPINNING FANCY YARNS WITH SAID METHOD AND FANCY YARN PRODUCED WITH SAID METHOD

Description

[0001] The present invention refers to a method and to a machine for spinning fancy yarns. It also refers to a fancy yarn manufactured by said method including fibres for adding effect inserted between the base fibres of said yarn.

BACKGROUND OF THE INVENTION

[0002] It is known to produce fancy yarns by the intermittent addition of one of several bundles of effect fibres of different colours or nature to a bundle or yarn of base fibres.

[0003] WO2011/018685 discloses a production method of fancy yarn in which the base fibres and the effect fibres are drafted separately to obtain a preset thickness, converging then the different bundles at a torsion spindle to form the yarn.

[0004] The fancy yarn manufactured by the method of said patent has the advantage that the desired contrast effect is obtained adding fibres of different nature or colour. However, this contrast effect can be enhanced applying a method such as that disclosed in CN1336453, US-A-2069446 or GB-A-25367.

[0005] CN1336453, US-A-2069446 and GB-A-25367 disclose methods for manufacturing a fancy yarn having the particularity that the bundles of effect fibres are added to the bundle of base fibres during the drafting step of said bundle of base fibres, all the fibres together obtaining the torsion. Specifically, the claimed methods comprise a step of injecting continuously a bundle of base fibres in a drafting train of said bundle of base fibres, and the step of injecting intermittently a bundle of effect fibres at said same drafting train when the bundle of base fibres is injected continuously.

[0006] The fancy yarn of the above-mentioned patents CN1336453, US-A-2069446 and GB-A-25367 have an enhanced chromatic contrast because during the drafting step the effect fibres are joined and are combined completely with the base fibres. However, this fancy yarn has some features that can be enhanced.

[0007] E.g. it has been observed that in the yarn of the above-mentioned patents the linear mass of aggregated fibres in each intermittent injection changes a lot from one injection to another, also resulting difficult to control the injection place of said fibres. On the other hand, it has been observed that the yarn manufactured by the methods of these patents have a great quantity of effect fibres that can be broken easily because they are not suitably joined to the base fibres.

[0008] WO-A-2008/068294 discloses a device and method for producing fancy yarn on a ring spinning machine having at least two support yarns which are twisted together and fibers of a roving which are introduced by means of a drafting device. A support yarn guide feeds in at least two support yarns which are at a distance from one another, in the region of a pair of rollers which are disposed in front of a spinning triangle.

[0009] The method of the above-mentioned patent application uses two support yarns to fix the position of the effect fibers of the roving so that the control of the injection place of the effect fibres is improved. However, the existence of two support yarns makes more difficult the spinning operation and does not allow to obtain the desired chromatic contrast because the effect fibres cannot join and combine completely with the base fibres of the two support yarns.

[0010] EP-A-1662027A discloses a device for producing special slub yarns. This device changes the speed of a front roller in accordance with a plurality of pattern data sets which show the change in thickness of spun yarn to produce special yarn corresponding to the pattern data including information on a pitch between slubs.

DESCRIPTION OF THE INVENTION

[0011] A first object of the present invention is to solve said drawbacks, providing a method and a machine for spinning fancy yarns presenting the advantages that will be described hereinafter.

[0012] A second object of the present invention is to solve said drawbacks, developing a fancy yarn with a high quality.

[0013] According to these objects, according to a first aspect, the present invention provides a method for spinning fancy yarns comprising the steps of:

a) injecting continuously a bundle of base fibres to a drafting train of said bundle of base fibres,

b) while said bundle of base fibres is continuously injected, injecting intermittently a bundle of effect fibres to said same drafting train to add intermittently said bundle of effect fibres to said bundle of base fibres, the intermittent injection of effect fibres of step b) including the steps of:

bi) advancing a stretch of said bundle of effect fibres to the drafting train of said bundle of base fibres, and

bii) then, moving backwardly said stretch a preset length, said backward movement permitting the forced cutting or separation of a fragment of the bundle of effect fibres to be added to the bundle of base fibres in said drafting train,

characterised in that after the injection of step b) the following step is carried out:

c) acceleration of the injection speed of the bundle of base fibres for producing a slubby in said bundle of base fibres, said acceleration being done at the moment when said fragment of the bundle of effect fibres is added to the base fibres, the injection place of said fragment matching with said slubby.

[0014] According to a second aspect, the present invention provides a machine for spinning fancy yarns according to the claimed method comprising a fibre drafting train provided, at each spinning position, with injection means of a bundle of base fibres and injection means of a bundle of effect fibres, said means for injecting effect fibres cooperating with said means for injection base fibres, so that said bundle of effect fibres is susceptible of being added intermittently to said bundle of base fibres in the same drafting train, said means for injecting effect fibres being configured to permit a backward movement of a stretch of said bundle of effect fibres when said means for injecting effect fibres receives a backward movement signal from a processing and control unit of said machine, the machine being characterised in that said processing and control unit is configured to permit the acceleration of the injection speed of the bundle of base fibres for producing a slubby in said bundle of base fibres, said acceleration being done at the moment when said fragment of the bundle of effect fibres is added to the base fibres, the injection place of said fragment matching with said slubby.

[0015] According to a third aspect, the present invention provides a fancy yarn manufactured by the claimed method comprising a plurality of fragments of a bundle of effect fibres added in a discontinuous way to a bundle of base fibres. The fancy yarn is characterized in that it comprises a plurality of slubbies of said bundle of base fibres, each of said slubbies including one of said fragments of a bundle of effect fibres matching with an over-thickness of base fibres, said over-thickness being obtained by the punctual reduction of the drafting ratio of the bundle of base fibres that causes the accumulation of said fibres.

[0016] In the present invention, by fragment of a bundle of effect fibres is meant a stretch of a bundle of fibres for adding effect that has a substantially uniform linear mass of fibres.

[0017] In the present invention slubby means an over-thickness of base fibres of a yarn produced by the accumulation of fibres by a punctual reduction of the drafting ratio of the bundle of base fibres.

[0018] The claimed method has the advantage with respect to the methods of the prior art that the effect fibres are added to the bundle of base fibres in a very controlled way.

[0019] It has been observed that the accumulation of base fibres producing the slubby makes easier the control of the injection of the effect fibres, because it forces the massive exit of the added effect fibres. Therefore, the length of the additions is more regular (shorter and more compact) than those from the state of the art. Furthermore, it has been observed that the slubby enhances the effect of the effect fibres and makes easier their holding, which prevents said effect fibres to be loosened or broken easily, as in the yarns of the state of the art.

[0020] Furthermore, in the method of the present invention, the injection of effect fibres is carried out so that the drafting train of base fibres advances a stretch of the bundle of effect fibres and then, moves backwardly said stretch a preset length to permit the forced cut or separation of a fragment of the bundle of effect fibres. Thanks to this forced cut or separation, the addition of effect fibres is stopped at the desired moment, which positively impacts on the control and quality of the obtained fancy yarn. This is because the formation of said fragment prevents the injection of more fibres in the same bundle.

[0021] Another advantage of the claimed method is that the formation of said fragments permits the fibres to be added in more compact groups to the bundle of base fibres, which enhances the effect of the added fibres and also the quality of the obtained yarn.

[0022] Preferably, in step bii), the backward movement of said stretch of effect fibres is done at a speed higher than the injection speed of the bundle of base fibres on which the effect fibres are added.

[0023] It has been observed that if the backward movement speed of the stretch of effect fibres is higher than the injection speed of the bundle of base fibres, the cut or separation of said fragments is done more effectively (a cut more sharp and clean).

[0024] Again preferably, in step bi), said bundle of effect fibres is injected in the drafting train at a speed which is the same or lower than the injection speed of the bundle of base fibres.

[0025] Advantageously, said acceleration is done at the moment in which said fragment is placed between drafting belts of the drafting train of said bundle of base fibres.

[0026] It has been observed that this moment is the more suitable moment to control with a greater efficiency the length and thickness of the additions of effect fibres in the resulting yarn.

[0027] Preferably, according to said preferred embodiment, in step c), said injection speed of the bundle of base fibres is accelerated a preset time according to the desired slubby length, and is accelerated a preset value according to the desired thickness of the slubby.

[0028] It has been observed that the length and the thickness of the slubby can be controlled by a program that determines the acceleration value and time that is applied. Furthermore, it must be pointed out that the control of the length and thickness of the slubby involves itself a control of the length and thickness of the additions of effect fibres in the resulting yarn.

[0029] As stated previously, the present invention also provides a machine, particularly a continuous spinning machine, which has the advantage that permits to carry out said method.

[0030] The claimed machine has the particularity that it includes a I processing and control unit that is configured to permit the acceleration of the injection speed of the bundle of base fibres for producing a slubby in said bundle of base fibres at the moment when a fragment of the bundle of effect fibres is added to the base fibres, so that the injection place of said fragment matches with said slubby. Moreover, the drafting train of the fibres has injection means of the effect fibres that are configured to permit the backward movement of a stretch of said bundle of effect fibres when said fibre injecting means receives a backward movement signal from the processing and control unit that carries out the claimed method. This backward movement of the bundle of effect fibres produced by the injection means of effect fibres permits the forced cut or separation of a fragment of said bundle that is provided to be added to the bundle of base fibres.

[0031] Preferably, said injection means of a bundle of effect fibres includes, at each spinning position, at least a first pair of rollers between which said bundle of effect fibres extends when said machine is operating, said first pair of rollers being able to rotate in both directions to permit the advancement or backward movement of said bundle of effect fibres, and said injection means of a bundle of base fibres includes at each spinning position, at least a second pair of rollers between which said bundle of base fibres extends when said machine is operating, said second pair of rollers being placed according to the first pair of rollers to permit the intermittent addition of a fragment of a bundle of effect fibres to a bundle of base fibres passing by said second pair of rollers.

[0032] Advantageously, said machine comprises fibre drafting belts associated with said second pair of rollers.

[0033] According to a preferred embodiment, the drafting train of the machine comprises, at each spinning position, a first condenser element configured as a funnel arranged between said means for injecting effect fibres and said means for injecting base fibres, said first condenser element covering substantially the distance from the means for injecting effect fibres to the means for injecting base fibres to make easier the joining of said fragment of the bundle of effect fibres with the bundle of base fibres.

[0034] It has been observed that, as the first condenser covers the distance from the injecting means of the effect fibres to the injecting means of the base fibres, the feeding continuity of the fibre assembly is guaranteed, even with the intrinsic discontinuity in the feeding because of the formation of fragments of the bundle of effect fibres.

[0035] Advantageously, said first condenser element comprises a first inlet stretch as a mouth to join said fragment and said bundle of base fibres one besides the other, and a second outlet stretch as a tunnel to merge or join said fragment with said bundle of base fibres.

[0036] This shape of the condenser guarantees the feeding efficiency of the fibres to the drafting belts of the machine.

[0037] According the same preferred embodiment, the drafting train of said machine comprises, at each spinning position, support means of said first condenser element as a funnel, said support means including:

• a first support piece on which said first condenser element is fixed, said first support piece being able to be moved laterally, and
• a second support piece of said first support piece, said second support piece including a support strip that is joined to a chassis of said machine, said support strip permitting the lateral movement of said first support piece.

[0038] Said support strip has the following functions. On one hand, as it is joined to the chassis of the machine, it supports the first piece on which the first condenser is fixed and prevents its undesired vertical movement. On the other hand, acting as a spring, it permits the horizontal movement of the piece on which the first condenser is fixed, preventing the overcharge of the motor driving said piece.

[0039] The horizontal movement of the condenser and with it the fibre bundle passing by said fibre injecting means is necessary to prevent the premature wear of said means.

[0040] According to the same preferred embodiment, the drafting train comprises, at each spinning position, a second condenser element configured as a floating wedge, said second condenser element being placed at the outlet of the drafting belts associated with said injecting means of base fibres, permitting said second condenser element to unite the assembly of effect fibres and base fibres before their torsion.

[0041] It has been observed that the second condenser as a wedge can be placed at the outlet of the drafting belts associated with the injecting means of the base fibres, not being necessary to change the position of said means or the position of the drafting belts itself, as in the machine of the state of the art.

[0042] Actually, the machines of the state of the art use a condenser with a funnel shape at the outlet of the drafting bag. This condenser and the element that supports it occupy a space that is necessary to be obtained changing the position of the injecting means of the base fibres or of the drafting bag itself, which involves a loss of control of the quality of the yarn at the moment previous to the torsion. However, the condenser with a floating wedge shape of the present invention occupies very little space, so that it can be placed at the outlet of the drafting bag with no necessity of changing the position of said bag or the injecting means of base fibres.

[0043] Preferably, the drafting train of said machine comprises, at each spinning position, means for holding said second condenser as a floating wedge, said means including a support rod horizontally movable on a pressure arm of said drafting train.

[0044] This support rod and the second floating condenser itself are horizontally moved by the movement of the bundle of fibres itself at the outlet of the drafting belts of the machine and they occupy a very little space in the machine.

[0045] As stated previously, according to a third aspect, the present invention provides a fancy yarn manufactured by the claimed method presenting the particularity that it comprises a plurality of fragments of a bundle of effect fibres added in a discontinued way to a bundle of base fibres.

[0046] The additions of the effect fibres to the yarn of the present invention are formed from fragments of a bundle of effect fibres, so that they present a more uniform and compact aspect that considerably enhances the effect of the added fibres, and also the final quality of the obtained yarn.

[0047] As stated previously, thanks to the slubby, the length of the additions of effect fibres is more regular (more uniform and compact) than those of the state of the art. Furthermore, it has been confirmed that the slubby improves the effect of the effect fibres and makes easier its holding, which prevents said effect fibres to be loosened or broken easily, as with the yarns of the state of the art.

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] For a better understanding of what has been disclosed some examples are attached, in which diagrammatically and only as a non-limitative example, a practical case of embodiment is shown.

[0049] In said drawings,

Fig. 1 shows a side view of a drafting train of a machine for spinning fancy yarn of the state of the art.

Fig. 2 shows a side view of a drafting train of a preferred embodiment of a spinning machine of the present invention.

Fig. 3 shows a perspective view of the drafting train of Fig. 2.

Fig. 4 is an upper perspective view of the drafting train of Fig. 2 in which the upper rollers from the third line of rollers have been removed to see the detail of the floating wedge condenser.

Fig. 5 is a rear perspective view of the drafting train of Fig. 2.

Fig. 6 shows a view and a detail of a fancy yarn obtained with the claimed method.

DESCRIPTION OF A PREFERRED EMBODIMENT AND OF AN EXAMPLE OF OPERATION

[0050] As shown in Fig. 1 and as it is currently known, the drafting train 1 of a continuous spinning machine of the state of the art includes three lines or pairs of rollers 2a, 2b, 2c between which, in each spinning position, a bundle 3 of base fibres extends. These pairs of rollers 2a, 2b, and 2c rotate at different speeds and with the same rotation direction, and they are normally linked to each other by a gear transmission system.

[0051] Just one bundle 3 of base fibres extends through said three pairs of rollers 2a, 2b, 2c, and for each spinning position, which, when is subjected to increasing rotation speeds of said rollers 2a, 2b, 2c, produces a drafting of said bundle 3 so that its linear mass is decreased until a preset limit for forming a simple yarn with a determined thickness is reached. At the outlet of the last pair of rollers 2c, the fibres already drafted from the bundle 3 enter in a torsion spindle (not shown).

[0052] The lower rollers of each pair of rollers 2a, 2b, 2c are configured by cylinders that are mounted on trestles 4 that also support a bar 5 on which pressure arms 6 are mounted (one arm 6 for each two spinning positions). These pressure arms 6 have the function of placing and applying pressure of the upper rollers of the three lines of rollers (the rear one 2a, the intermediate one 2b and the frontal one 2c) on their respective lower rollers.

[0053] As shown in the same Fig. 1, the drafting train 1 of the state of the art also includes, for each spinning position, condensers 7 that have the function of guiding the bundle 3 of base fibres when it enters to the first pair 2a of rollers, and drafting belts 8 placed between the second 2b and the third 2c pair of rollers. These drafting belts 8 determine what is commonly defined as a fibre-drafting bag 9.

[0054] Hereinafter one embodiment of the spinning machine and the method of the present invention are described, making reference to Figs. 2-5.

[0055] The machine of the present invention comprises a drafting train 1 that presents the particularity that, at each spinning position, the first pair 2a of rollers is responsible of injecting a bundle 10 of effect fibres, the second pair 2b of rollers injects now the bundle 3 of base fibres.

[0056] In the disclosed machine, the first pair 2a of rollers, which constitute what in the present specification has been identified as means for injecting a bundle 10 of effect fibres, is driven by a servomotor through a processing and control unit that is programmed to inject intermittently the bundle 10 of effect fibres to the bundle 3 of base fibres. This injection of the effect fibres is done during the continuous injection of said bundle 3 of base fibres through the second pair 2b of rollers that is driven by a second servomotor associated with the same processing and control unit.

[0057] As stated previously in the description of the invention, in the claimed method the injection of effect fibres is done advancing a stretch of the bundle 10 of effect fibres, and then moving back said stretch a preset length to permit the forced cut or separation of a fragment of the bundle 10 of the effect fibres to be added to the bundle 3 of base fibres. Thanks to this forced cut or separation, the addition of effect fibres is stopped at the desired moment, which positively impacts on the control and quality of the obtained fancy yarn.

[0058] To carry out said backward movement of the stretch of effect fibres, the first pair 2a of rollers is configured to rotate in a direction opposed to the advance direction, when the servomotor that drives said rollers 2a receives a backward movement signal from said processing and control unit.

[0059] In the disclosed embodiment, the processing and control unit has been programmed so that the backward movement of the bundle 10 of effect fibres is done at a speed that is higher than the injection speed of the bundle 3 of base fibres, because it has been observed that the cut or separation of the fragments is done in a more efficient way (a cut more sharp and clean).

[0060] Turning back to the same processing and control unit of the machine, it must be pointed out that this unit has been programmed to accelerate the injection speed of the bundle 3 of base fibres (speed of the second pair 2b of rollers) just at the moment in which a fragment of one bundle 10 of effect fibres is added in the drafting bag 9 to the bundle 3 of base fibres. Therefore, the injection place of said fragment matches with a slubby produced because of this acceleration.

[0061] The accumulation of fibres that produces the slubby (drafting reduction) has the advantage that makes easier the control of the length and the thickness of the injection of effect fibres, increases the effect of said fibres and makes easier its holding.

[0062] As shown in Fig. 2, at each spinning position, the bundle 10 of effect fibres is added to the bundle 3 of base fibres through a first condenser element 11 configured as a funnel that is placed between the first pair 2a of rollers and the second pair 2b of rollers.

[0063] This first condenser element 11 includes a first inlet stretch 11a (see Fig. 4) as a mouth that has a width enough to permit that each fragment of the bundle 10 of effect fibres and the bundle 3 of base fibres are joined one besides the other instead of one on the other, as in the state of the art. The same first condenser element 11 includes a second outlet stretch 11b as a tunnel to merge or join each fragment of the bundle 10 of effect fibres with the bundle 3 of base fibres.

[0064] Another key element of the drafting train 1 of the claimed machine is the second condenser element 12 configured as a floating wedge that is placed at the outlet of the drafting bag 9 of each spinning position.

[0065] In Fig. 4 is shown in detail the substantially flat shape of said second condenser 12, which permit its placement between the second 2b and third 2c pair of rollers not changing the position of said rollers of the drafting bag 9 itself. This condenser 12 guarantees the cohesion of the fibres before the torsion, preventing the loss by aspiration of a great number of effect fibres.

[0066] Regarding the first condenser 11 with a funnel shape, it is fixed on a banister 13 that can be horizontally moved when it receives the oscillating movement from an engine. This banister 13 is joined to the chassis of the machine; particularly to the bar 5 on which the pressure arms 6 are mounted, through a strip 14 (see Fig. 5).

[0067] As stated previously, the strip 14 has the advantage that, on the one hand, it prevents the vertical movement of the banister 13 and, on the other hand, it acts as a spring permitting the horizontal movement of the banister 13 and prevents the overcharge of the engine through which said banister 13 is driven.

[0068] The horizontal movement of the banister 13, and with it the first condenser 11, is necessary to prevent the premature wear of the upper rollers 2b, 2c produced by the passage of the fibres.

[0069] Regarding the second condenser element 12 with a floating wedge shape, this is held by a rod 15 associated to the pressure arm 6 that holds the upper rollers 2a, 2b, 2c. This rod 15 can be horizontally moved on the arm 6 when the condenser 12 itself moves with the movement of the fibres produced by said banister 13.

[0070] As shown in detail in Fig. 4, the ends of the same rod 15 hold each one condenser 12, so that the same rod 15 can be used for two spinning positions.

[0071] Hereinafter an operation example of the method and the machine of the present invention are disclosed.

[0072] According to the kind of yarn to be produced, the processing and control unit is first programmed with the following input data:

• Basic draft ratio or number of times that the speed of the second pair of rollers 2b is lower than the speed of the third pair of rollers 2c for producing the drafting.
• Maximum and minimum separation length between additions of effect fibre.
• Length of the injected bundle 10 of effect fibres.
• Injection speed of the bundle 10 of effect fibres expressed as the ratio of the speed of the first pair 2a of rollers with respect to the second pair 2b of rollers.
• Backward movement length of the injected bundle 10 of effect fibres.
• Backward movement speed of the injected bundle 10 of fibres expressed as the ratio of the speed of the first pair 2a of rollers with respect to the second pair 2b of rollers.
• Slubby length that determines the acceleration time applied to the second pair 2b of rollers at the time that a fragment of the bundle 10 of effect fibres is added to the bundle 3 of base fibres in the drafting bag 9.
• Slubby thickness or number of times that the speed of the second pair 2b of rollers is increased with respect to the third pair 2c of rollers for producing the accumulation of slubby fibres (drafting reduction).

[0073] In the described example, the spinning of a fancy yarn made from a bundle 3 of white base fibres and a bundle 10 of blue effect fibres is pretended. In this specific case, the processing and control unit has been programmed to produce the fancy yarn as follows:

• Basic drafting ratio: 14.0, which is the number of times that the speed of the second pair of rollers 2b is lower than the speed of the third pair of rollers 2c to produce the drafting.
• Maximum separation length between additions: 850 mm
• Minimum separation length between additions: 1275 mm
• Length of the injected bundle 10 of effect fibre: 15 mm
• Injection speed of the bundle 10 of effect fibres: 1.20, which indicates the ratio of the speed of the first pair 2a of rollers with respect to the second pair 2b of rollers (in this case, 20% less velocity than the first pair 2a of rollers).
• Backward movement length of the injected bundle 10 of effect fibres: 5 mm.
• Backward movement speed of the injected bundle 10 of fibres: 0.40, which indicates the ratio of the speed of the first pair 2a of rollers with respect to the second pair 2b of rollers (in this case, 60% more speed than the first pair 2a of rollers).
• Slubby length: 20 mm.
• Slubby thickness: 3.00 or number of times that the speed of the second pair 2b of rollers is increased with respect to the speed of the third pair 2c of rollers to produce the accumulation of slubby fibres (drafting reduction).

[0074] The process is started, at each spinning position, in the moment that the first pair 2a of rollers is started driven by an independent servomotor for injecting an intermittent stretch of bundle 10 of effect fibres in the bundle 3 of base fibres that is being injected by the second pair 2b of rollers. This injection moment of the effect fibres is ordered by the processing and control unit through a "random" system that takes into account the maximum and minimum separation lengths between fibre additions to prevent the production of what is known as "moirée" or geometric repetition.

[0075] In the described example, the length of the injected bundle 10 of effect fibres is 15 mm and the injection speed of the bundle 10 of effect fibres (speed of the first pair 2a of rollers) is a 20% lower than the injection speed of the bundle 3 of base fibres (speed of the second pair 2b of rollers).

[0076] Once the programmed length of the bundle 10 of effect fibres has been injected, the first pair 2a of rollers is stopped and they begin the rotation in the opposite direction moving backwardly a stretch of the bundle 10 of effect fibres a preset length, said back movement permitting the cut or separation of a fragment to be added to the bundle 3 of base fibres in the drafting train 1.

[0077] In the disclosed example, the backward movement length of the stretch of effect fibres is 5 mm and the back movement speed of said stretch is a 60% higher than the injection speed of the bundle 3 of effect fibres (speed of the second pair 2b of rollers).

[0078] Once finished the injection of effect fibres, the fragment of the bundle 10 of effect fibres cut or separated is inserted inside the drafting bag 9 to be added to the bundle 3 of base fibres. In this moment, an acceleration of the injection speed of the base fibres is produced (speed of the second pair 2b of rollers) that produces an accumulation of fibres producing the slubby, matching the injection place of the fragment of effect fibres with said slubby.

[0079] In the disclosed example, the processing and control unit has been programmed to provide a slubby with a length of 20 mm and a preset thickness that is obtained increasing 3 times the injection speed of the base fibres 3 (speed of the rollers 2b of the second line) with respect to the speed of the rollers 2c of the third line.

[0080] As stated previously, it has been observed that the slubby makes easier the control of the length and thickness of the additions of the effect fibres, and improves the effect of said fibres.

[0081] Fig. 6 shows a view and a detail of a fancy yarn 16 obtained with the claimed method. In this yarn 16, the additions 16a of effect fibres match each with a slubby 17 of the base fibres 3. As shown in Fig. 6, thanks to the formation of the fragments and the slubby, the additions have a uniform and compact aspect providing the yarn a great quality.

[0082] Even though that a specific embodiment of the present invention has been described and shown, it is apparent that the person skilled in the art can introduce variations and modifications, or he/she can substitute the details by other technically equivalent ones, without departing from the scope of protection defined by the attached claims.

Claims

1. Method for spinning fancy yarns (16) comprising the steps of:

a) injecting continuously a bundle (3) of base fibres to a drafting train (1) of said bundle (3) of base fibres,

b) while said bundle (3) of base fibres is continuously injected, injecting intermittently a bundle (10) of effect fibres to said same drafting train (1) to add intermittently said bundle (10) of effect fibres to said bundle (3) of base fibres, the intermittent injection of effect fibres of step b) including the steps of:

bi) advancing a stretch of said bundle (10) of effect fibres to the drafting train (1) of said bundle (3) of base fibres, and

bii) then, moving backwardly said stretch a preset length, said backward movement permitting the forced cutting or separation of a fragment of the bundle (10) of effect fibres to be added to the bundle (3) of base fibres in said drafting train (1),

characterised in that after the injection of step b) the following step is carried out:

c) acceleration of the injection speed of the bundle (3) of base fibres for producing a slubby (17) in said bundle (3) of base fibres, said acceleration being done at the moment when said fragment of the bundle (10) of effect fibres is added to the base fibres, the injection place of said fragment matching with said slubby (17).

2. Method according to claim 1, wherein, in step bii), the backward movement of said stretch of effect fibres is done at a speed higher than the injection speed of the bundle (3) of base fibres on which the effect fibres are added.

3. Method according to anyone of the previous claims, wherein, in said step bi), said bundle (10) of effect fibres is injected in the drafting train (1) at a speed that is the same or lower than the injection speed of the bundle (3) of base fibres.

4. Method according to claim 1, wherein, in step c), said injection speed of the bundle (3) of base fibres is accelerated a preset time according to the desired slubby length (17), and is accelerated a preset value according to the desired slubby (17) thickness.

5. Method according to claim 1, wherein the acceleration step c) is carried out at the moment in which said fragment of the bundle (10) of effect fibres is placed between drafting belts (8) of the drafting train (1) of said bundle (3) of base fibres.

6. Machine for spinning fancy yarns (16) according to the method of claims 1 to 5, comprising a fibre drafting train (1) provided, at each spinning position, with injection means (2b) of a bundle (3) of base fibres and injection means (2a) of a bundle (10) of effect fibres, said means (2a) for injecting effect fibres cooperating with said means (2b) for injection base fibres so that said bundle (10) of effect fibres is susceptible of being added intermittently to said bundle (3) of base fibres in the same drafting train (1), said means (2a) for injecting effect fibres being configured to permit a backward movement of a stretch of said bundle (10) of effect fibres when said means (2a) for injection effect fibres receives a backward movement signal from a processing and control unit of said machine, said machine being characterized in that said processing and control unit is configured to permit the acceleration of the injection speed of the bundle of base fibres for producing a slubby in said bundle of base fibres, said acceleration being done at the moment when said fragment of the bundle of effect fibres is added to the base fibres, the injection place of said fragment matching with said slubby.

7. Machine according to claim 6, wherein:

- said injection means of a bundle (10) of effect fibres includes, at each spinning position, at least a first pair (2a) of rollers between which said bundle (10) of effect fibres extends when said machine is operating, said first pair of rollers (2a) being able to rotate in both directions to permit the advancement or backward movement of said bundle (10) of effect fibres,

- said injection means of a bundle (3) of base fibres includes, at each spinning position, at least a second pair (2b) of rollers between which said bundle (3) of base fibres extends when said machine is operating, said second pair of rollers (2b) being placed according to the first pair of rollers (2a) to permit the intermittent addition of a fragment of a bundle (10) of effect fibres to a bundle (3) of base fibres passing by said second pair (2b) of rollers.

8. A machine according to claim 7, comprising belts (8) for drafting fibres associated with said second pair of rollers (2b).

9. Machine according to anyone of claims 6-8, wherein said drafting train (1) comprises, at each spinning position, a first condenser element (11) configured as a funnel that is arranged between said means (2a) for injecting effect fibres and said means (2b) for injecting base fibres, said first condenser element (11) covering substantially the distance from the means (2a) for injecting effect fibres to the means (2b) for injecting base fibres to make easier the joining of said fragment of the bundle (10) of effect fibres with the bundle (3) of base fibres.

10. Machine according to claim 9, wherein said first condenser element (11) comprises a first inlet stretch (11 a) as a mouth to join said fragment and said bundle (3) of base fibres one besides the other, and a second outlet stretch (11b) as a tunnel to merge or join said fragment with said bundle (3) of base fibres.

11. Machine according to anyone of claims 9-10, wherein said drafting train (1) comprises, at each spinning position, support means of said first condenser element (11) as a funnel, said support means comprising:

- a first support piece (13) on which said first condenser element (11) is fixed, said first support piece (13) being able to be moved laterally, and

- a second support piece of said first support piece (13), said second support piece including a support strip (14) that is joined to a chassis (5) of said machine, said support strip (14) permitting the lateral movement of said first support piece (13).

12. Machine according to anyone of claims 8-11, wherein said drafting train (1) comprises, at each spinning position, a second condenserelement (12) configured as a floating wedge, said second condenser element (12) being placed at the outlet of the drafting belts (8) associated with said means (2b) for injecting base fibres, permitting said second condenser element (12) the cohesion of the assembly of effect fibres and base fibres before their torsion.

13. Machine according to claim 12, wherein said drafting train (1) comprises, at each spinning position, means for holding said second condenser element (12) as a floating wedge, said means including a support rod (15) that can be moved horizontally on a pressure arm (6) of said drafting train (1).

14. Fancy yarn (16) manufactured by the method according to anyone of claims 1-5 said fancy yarn comprising a plurality of fragments of a bundle (10) of effect fibres added in a discontinuous way to a bundle (3) of base fibres, characterised in that it comprises a plurality of slubbies (17) of said bundle (3) of base fibres, each of said slubbies (17) including one of said fragments of a bundle (10) of effect fibres matching with an over-thickness of base fibres, said over-thickness being obtained by the punctual reduction of the drafting ratio of the bundle (3) of base fibres that causes the accumulation of said fibres.

Ansprüche

1. Verfahren zum Spinnen von Effektgarnen (16), das folgende Schritte aufweist:

a) kontinuierliches Einführen eines Bündels (3) von Basisfasern in eine Einzugsbahn (1) des Bündels (3) von Basisfasern,

b) periodisches Einführen eines Bündels (10) von Effektgarnen in die Einzugsbahn (1), um das Bündel (10) von Effektgarnen zu dem Bündel (3) von Basisfasern hinzuzugeben, während das Bündel (3) von Basisfasern kontinuierlich eingeführt wird, wobei das periodische Einführen des Effektgarns von Schritt b) folgende Schritte umfasst:

bi) Voranbewegen einer Dehnung des Bündels (10) von Effektgarnen an der Einzugsbahn (1) des Bündels (3) von Basisfasern, und

bii) anschließendes Zurückbewegen der Dehnung um eine vorgegebene Länge, wobei die Rückwärtsbewegung den erzwungenen Schnitt oder das erzwungene Abtrennen eines Fragments des Bündels (10) von Effektgarnen zulässt, um dem Bündel (3) von Basisfasern in der Einzugsbahn (1) hinzugegeben zu werden,

dadurch gekennzeichnet, dass
nach dem Einführen von Schritt b) folgender Schritt durchgeführt wird:

c) Hochfahren der Einführgeschwindigkeit des Bündels (3) von Basisfasern zum Herstellen einer Unregelmäßigkeit (17) in dem Bündel (3) von Basisfasern, wobei das Hochfahren in dem Moment durchgeführt wird, in dem das Fragment des Bündels (10) von Effektgarnen den Basisfasern hinzugegeben wird, wobei die Einführstelle des Fragments mit der Unregelmäßigkeit (17) übereinstimmt.

2. Verfahren nach Anspruch 1, wobei in Schritt bi) die Rückwärtsbewegung der Dehnung der Effektgarne in einer höheren Geschwindigkeit durchgeführt wird als die Einführgeschwindigkeit des Bündels (3) von Basisfasern, zu welchen die Effektgarne hinzugegeben werden.

3. Verfahren nach Anspruch 1 oder 2, wobei in Schritt bi) das Bündel (10) von Effektgarnen in die Einzugsbahn (1) mit einer Geschwindigkeit eingeführt wird, die gleich oder geringer ist, als die Einführgeschwindigkeit des Bündels (3) von Basisfasern.

4. Verfahren nach Anspruch 1, wobei in Schritt c) die Einführgeschwindigkeit des Bündels (3) von Basisfasern zu einer vorgegebenen Zeit gemäß der erwünschten Länge der Unregelmäßigkeit (17) und zu einem vorgegebenen Wert gemäß der erwünschten Dicke der Unregelmäßigkeit (17) hochgefahren wird.

5. Verfahren nach Anspruch 1, wobei der Schritt c) des Hochfahrens in dem Moment durchgeführt wird, in dem das Fragment des Bündels (10) von Effektgarnen zwischen Einziehriemen (8) der Einzugsbahn (1) des Bündels (3) von Basisfasern angeordnet ist.

6. Maschine zum Spinnen von Effektgarnen (16) gemäß dem Verfahren nach den Ansprüchen 1 bis 5, wobei die Maschine eine Fasereinzugsbahn (1) aufweist, die an jeder Spinnstelle mit Einführmitteln (2b) eines Bündels (3) von Basisfasern und Einführmitteln (2a) eines Bündels (10) von Effektgarnen versehen ist, wobei die Mittel (2a) zum Einführen von Effektgarnen mit den Mitteln (2b) zum Einführen der Basisfasern derart zusammenwirken, dass das Bündel (10) von Effektgarnen geeignet ist, periodisch zu dem Bündel (3) von Basisfasern in der gleichen Einzugsbahn (1) hinzugegeben zu werden, wobei die Mittel (2a) zum Einführen der Effektgarne derart ausgestaltet sind, dass sie eine Rückwärtsbewegung einer Dehnung des Bündels (10) von Effektgarnen zulassen, wenn die Mittel (2a) zum Einführen der Effektgarne ein Rückwärtsbewegungssignal von einer Verarbeitungs-und Steuereinheit der Maschine empfangen, wobei die Maschine dadurch gekennzeichnet ist, dass die Verarbeitungs- und Steuereinheit derart ausgestaltet ist, dass sie das Hochfahren der Einführgeschwindigkeit der Bündel von Basisfasern zum Herstellen einer Unregelmäßigkeit in dem Bündel von Basisfasern zulassen, wobei das Hochfahren in dem Moment durchgeführt wird, in dem das Fragment des Bündels von Effektgarnen zu den Basisfasern hinzugegeben wird, wobei die Einführstelle des Fragments mit der Unregelmäßigkeit übereinstimmt.

7. Maschine nach Anspruch 6, wobei:

- die Einführmittel eines Bündels (10) von Effektgarnen an jeder Spinnstelle mindestens ein erstes Walzenpaar (2a) umfasst, zwischen denen sich das Bündel (10) von Effektgarnen erstreckt, wenn die Maschine in Betrieb ist, wobei das mindestens erste Walzenpaar (2a) in der Lage ist, sich in beide Richtungen zu drehen, um die Vorwärts- oder Rückwärtsbewegung des Bündels (10) von Effektgarnen zuzulassen,

- die Einführmittel eines Bündels (3) an Basisfasern an jeder Spinnstelle mindestens ein zweites Walzenpaar (2b) umfasst, zwischen denen sich das Bündel (3) von Basisfasern erstreckt, wenn die Maschine in Betrieb ist, wobei das zweite Walzenpaar (2b) das periodische Hinzugeben eines Fragments eines Bündels (10) von Effektgarnen zu dem Bündel (3) von Basisfasern, die an dem Walzenpaar (2b) vorbeilaufen, zulässt.

8. Maschine nach Anspruch 7, wobei die Maschine Riemen (8) zum Einziehen von Fasern aufweist, die mit dem zweiten Walzenpaar (2b) verbunden sind.

9. Maschine nach einem der Ansprüche 6 bis 8, wobei die Einzugsbahn (1) an jeder Spinnstelle ein erstes Verdichterelement (11) aufweist, das als ein Trichter ausgestaltet ist, der zwischen den Mitteln (2a) zum Einführen von Effektgarnen und den Mitteln (2b) zum Einführen von Basisfasern angeordnet ist, wobei das erste Verdichterelement (11) im Wesentlichen den Abstand von den Mitteln (2a) zum Einführen von Effektgarnen zu den Mitteln (2b) zum Einführen von Basisfasern abdeckt, um das Zusammenführen des Fragments des Bündels (10) von Effektgarnen mit dem Bündel (3) von Basisfasern zu erleichtern.

10. Maschine nach Anspruch 9, wobei das erste Verdichterelement (11) einen ersten Einlassabschnitt (11a) wie zum Beispiel ein Mundstück, um das Fragment und das Bündel (3) von Basisfasern nebeneinander zusammenzufügen, und einen zweiten Auslassabschnitt (11 b) wie zum Beispiel einen Tunnel aufweist, um das Fragment mit dem Bündel (3) von Basisfasern zusammenzulegen oder zusammenzufügen.

11. Maschine nach Anspruch 9 oder 10, wobei die Einzugsbahn (1) an jeder Spinnstelle Förderelemente des Verdichterelements (11) wie einen Trichter aufweist, wobei die Förderelemente aufweisen:

- ein erstes Trägerteil (13), an dem das Verdichterelement (11) befestigt ist, wobei das erste Trägerteil (13) in der Lage ist, seitlich verschoben zu werden, und

- ein zweites Trägerteil des ersten Trägerteils (13), wobei das zweite Trägerteil einen Trägerstreifen (14) umfasst, der mit einem Chassis (5) der Maschine verbunden ist, wobei der Trägerstreifen (14) die seitliche Bewegung des ersten Trägerteils (13) zulässt.

12. Maschine nach einem der Ansprüche 8 bis 11, wobei die Einzugsbahn (1) an jeder Spinnstelle ein zweites Verdichterelement (12) aufweist, das als ein gleitendes Keilstück ausgestaltet ist, wobei das zweite Verdichterelement (12) an dem Auslass der Einzugsriemen (8) angeordnet ist, die mit dem Mittel (2b) zum Einführen von Basisfasern verbunden sind, wobei das zweite Verdichterelement (12) den Zusammenhalt der Vereinigung der Effektgarne mit den Basisfasern vor ihrer Verdrehung zulässt.

13. Maschine nach Anspruch 12, wobei die Einzugsbahn (1) an jeder Spinnstelle Mittel zum Halten des zweiten Verdichterelements (12) wie ein gleitendes Keilstück aufweist, wobei die Mittel eine Tragstange (15) umfassen, die horizontal an einem Druckarm (6) der Einzugsbahn (1) bewegt werden kann.

14. Effektgarn (16), das nach dem Verfahren nach einem der Ansprüche 1 bis 5 hergestellt wird, wobei das Effektgarn eine Mehrzahl von Fragmenten eines Bündels (10) von Effektgarnen aufweist, die in einer unstetigen Weise zu einem Bündel (3) von Basisfasern hinzugegeben werden, dadurch gekennzeichnet, dass es eine Mehrzahl an Unregelmäßigkeiten (17) in dem Bündel (3) von Basisfasern aufweist, wobei jede der Unregelmäßigkeiten (17) eines der Fragmente eines Bündels (10) von Effektgarnen umfasst, die mit einer Überdicke der Basisfasern übereinstimmen, wobei die Überdicke durch eine rechtzeitige Verringerung des Einzugsverhältnisses des Bündels (3) von Basisfasern, das die Anhäufung der Fasern verursacht, erreicht wird.

Revendications

1. Procédé de filature de fils fantaisie (16) comportant les étapes consistant à :

a) injecter en continu un faisceau (3) de fibres de base dans un train d'étirage (1) dudit faisceau (3) de fibres de base,

b) pendant que ledit faisceau (3) de fibres de base est injecté en continu, injecter par intermittence un faisceau (10) de fibres d'effet dans le même train d'étirage (1) pour ajouter par intermittence ledit faisceau (10) de fibres d'effet audit faisceau (3) de fibres de base, l'injection intermittente de fibres d'effet de l'étape b) incluant les étapes consistant à :

bi) faire avancer un tronçon dudit faisceau (10) de fibres d'effet dans le train d'étirage (1) dudit faisceau (3) de fibres de base, et

bii) ensuite, faire reculer ledit tronçon sur une longueur prédéfinie, ledit mouvement de recul permettant le coupage ou la séparation forcée d'un fragment du faisceau (10) de fibres d'effet à ajouter au faisceau (3) de fibres de base dans ledit train d'étirage (1),

caractérisé en ce que, après l'injection de l'étape b) l'étape suivante est réalisée :

c) accélération de la vitesse d'injection du faisceau (3) de fibres de base pour produire un renflement (17) dans ledit faisceau (3) de fibres de base, ladite accélération étant réalisée au moment où ledit fragment du faisceau (10) de fibres d'effet est ajouté aux fibres de base, le lieu d'injection dudit fragment correspondant audit renflement (17).

2. Procédé selon la revendication 1, dans lequel, à l'étape bii), le mouvement de recul dudit tronçon de fibres d'effet est réalisé à une vitesse supérieure à la vitesse d'injection du faisceau (3) de fibres de base sur lequel les fibres d'effet sont ajoutées.

3. Procédé selon l'une quelconque des revendications précédentes, dans lequel, à ladite étape bi), ledit faisceau (10) de fibres d'effet est injecté dans le train d'étirage (1) à une vitesse qui est identique ou inférieure à la vitesse d'injection du faisceau (3) de fibres de base.

4. Procédé selon la revendication 1, dans lequel, à l'étape c), ladite vitesse d'injection du faisceau (3) de fibres de base est accélérée pendant une durée prédéfinie selon la longueur souhaitée du renflement (17), et est accélérée conformément à une valeur prédéfinie selon l'épaisseur souhaitée du renflement (17).

5. Procédé selon la revendication 1, dans lequel l'étape d'accélération c) est réalisée au moment où ledit fragment du faisceau (10) de fibres d'effet est placé entre des courroies d'étirage (8) du train d'étirage (1) dudit faisceau (3) de fibres de base.

6. Machine pour la filature de fils fantaisie (16) selon le procédé des revendications 1 à 5, comprenant un train d'étirage de fibres (1) pourvu, à chaque position de filature, de moyens d'injection (2b) d'un faisceau (3) de fibres de base et de moyens d'injection (2a) d'un faisceau (10) de fibres d'effet, lesdits moyens (2a) pour injecter des fibres d'effet coopérant avec lesdits moyens (2b) pour l'injection de fibres de base de sorte que ledit faisceau (10) de fibres d'effet est susceptible d'être ajouté par intermittence audit faisceau (3) de fibres de base dans le même train d'étirage (1), lesdits moyens (2a) pour injecter des fibres d'effet étant configurés pour permettre un mouvement de recul d'un tronçon dudit faisceau (10) de fibres d'effet quand lesdits moyens (2a) pour l'injection de fibres d'effet reçoivent un signal de mouvement de recul d'une unité de traitement et de commande de ladite machine, ladite machine étant caractérisée en ce que ladite unité de traitement et de commande est configurée pour permettre l'accélération de la vitesse d'injection du faisceau de fibres de base pour produire un renflement dans ledit faisceau de fibres de base, ladite accélération étant réalisée au moment où ledit fragment du faisceau de fibres d'effet est ajouté aux fibres de base, le lieu d'injection dudit fragment correspondant audit renflement.

7. Machine selon la revendication 6, dans laquelle :

- lesdits moyens d'injection d'un faisceau (10) de fibres d'effet incluent, à chaque position de filature, au moins une première paire (2a) de cylindres entre lesquels s'étend ledit faisceau (10) de fibres d'effet quand ladite machine est en fonctionnement, ladite première paire de cylindres (2a) étant apte à tourner dans les deux sens pour permettre le mouvement d'avance ou de recul dudit faisceau (10) de fibres d'effet,

- lesdits moyens d'injection d'un faisceau (3) de fibres de base incluent, à chaque position de filature, au moins une deuxième paire (2b) de cylindres entre lesquels s'étend ledit faisceau (3) de fibres de base quand ladite machine est en fonctionnement, ladite deuxième paire de cylindres (2b) étant placée en fonction de la première paire de cylindres (2a) pour permettre l'ajout intermittent d'un fragment d'un faisceau (10) de fibres d'effet à un faisceau (3) de fibres de base passant par ladite deuxième paire (2b) de cylindres.

8. Machine selon la revendication 7, comprenant des courroies (8) pour l'étirage de fibres associées à ladite deuxième paire de cylindres (2b).

9. Machine selon l'une quelconque des revendications 6-8, dans laquelle ledit train d'étirage (1) comprend, à chaque position de filature, un premier élément condenseur (11) configuré comme un entonnoir qui est agencé entre lesdits moyens (2a) pour injecter des fibres d'effet et lesdits moyens (2b) pour injecter des fibres de base, ledit premier élément condenseur (11) couvrant sensiblement la distance entre les moyens (2a) pour injecter des fibres d'effet et les moyens (2b) pour injecter des fibres de base afin de faciliter le raccord dudit fragment du faisceau (10) de fibres d'effet avec le faisceau (3) de fibres de base.

10. Machine selon la revendication 9, dans laquelle ledit premier élément condenseur (11) comprend un premier tronçon d'entrée (11a) sous la forme d'une bouche pour raccorder ledit fragment et ledit faisceau (3) de fibres de base l'un à côté de l'autre, et un deuxième tronçon de sortie (11 b) sous la forme d'un tunnel pour fusionner ou raccorder ledit fragment avec ledit faisceau (3) de fibres de base.

11. Machine selon l'une quelconque des revendications 9-10, dans laquelle ledit train d'étirage (1) comprend, à chaque position de filature, des moyens de support dudit premier élément condenseur (11) sous la forme d'un entonnoir, lesdits moyens de support comprenant :

- une première pièce de support (13) sur laquelle ledit premier élément condenseur (11) est fixé, ladite première pièce de support (13) étant apte à être déplacée latéralement, et

- une deuxième pièce de support de ladite première pièce de support (13), ladite seconde pièce de support incluant une bande de support (14) qui est raccordée à un châssis (5) de ladite machine, ladite bande de support (14) permettant le mouvement latéral de ladite première pièce de support (13).

12. Machine selon l'une quelconque des revendications 8-11, dans laquelle ledit train d'étirage (1) comprend, à chaque position de filature, un deuxième élément condenseur (12) configuré sous la forme d'une cale flottante, ledit deuxième élément condenseur (12) étant placé à la sortie des courroies d'étirage (8) associées auxdits moyens (2b) pour injecter des fibres de base, en permettant audit deuxième élément condenseur (12) la cohésion de l'assemblage de fibres d'effet et de fibres de base avant leur torsion.

13. Machine selon la revendication 12, dans laquelle ledit train d'étirage (1) comprend, à chaque position de filature, des moyens pour maintenir ledit deuxième élément condenseur (12) sous la forme d'une cale flottante, lesdits moyens incluant une tige de support (15) qui peut être déplacée horizontalement sur un bras de pression (6) dudit train d'étirage (1).

14. Fil fantaisie (16) fabriqué par le procédé selon l'une quelconque des revendications 1-5, ledit fil fantaisie comprenant une pluralité de fragments d'un faisceau (10) de fibres d'effet ajoutés d'une manière discontinue à un faisceau (3) de fibres de base, caractérisé en ce qu'il comprend une pluralité de renflements (17) dudit faisceau (3) de fibres de base, chacun desdits renflements (17) incluant l'un desdits fragments d'un faisceau (10) de fibres d'effet correspondant à une surépaisseur de fibres de base, ladite surépaisseur étant obtenue par la réduction ponctuelle du rapport d'étirage du faisceau (3) de fibres de base qui provoque l'accumulation desdites fibres.

Drawing