DE102008005379A1 - Producing fine hosiery on knitting machine, by supplying yarns on yarn running path from cops and bobbins to knitting point of the machine, and releasing length variation of yarn on yarn running path before entering into the knitting point - Google Patents

Abstract

The method comprises supplying yarns (1) on a yarn running path from cops (2) and bobbins to a knitting point (3) of a knitting machine, in which the yarn is knitted in a knitted fabric, and releasing the length variation of the yarn on the yarn running path before entering into the knitting point. The yarn is permanently changeable by external effect in its length. The yarn in the yarn running path is kept under a predetermined tension. The yarn is shrunken by producing a volume effect and is elongated. The yarn stretches in the yarn running path and is released by stretching a yarn ripple. The method comprises supplying yarns (1) on a yarn running path from cops (2) and bobbins to a knitting point (3) of a knitting machine, in which the yarn is knitted in a knitted fabric, and releasing the length variation of the yarn on the yarn running path before entering into the knitting point. The yarn is permanently changeable by external effect in its length. The yarn in the yarn running path is kept under a predetermined tension. The yarn is shrunken by producing a volume effect and is elongated. The yarn stretches in the yarn running path and is released by stretching a yarn ripple or a loop formation. The yarn is stretched to 25% during the stretching. The stretching of the yarn takes place in the yarn running path by two yarn delivery devices (6, 7), which are arranged one after another and separated from each other in a distance. A multi-component yarn is used as yarn, where the yarn components are permanently changeable in their length. The yarn delivery devices convey the yarn with different delivery speeds and have driven yarn delivery drums (9) surrounded by the yarn. The yarn delivery drums rotate with different peripheral speeds, are driven with same number of revolutions, have different diameters and are coaxially arranged to each other. The yarn is implemented in the yarn running path through a thermal treatment zone, in which the yarn is exposed to a thermal effect. The yarn in the thermal treatment zone is exposed to the effect of a radiation of a gaseous heat transmission means and is guided over a heating element. A heated element surrounded by the yarn is used as the heating element. The yarn is subjected to a heat treatment in addition to the stretching. The yarn is guided over the heated yarn delivery drum of the yarn delivery device. The yarn is subjected to the thermal effect in a stretching area lying between the yarn delivery devices. The multi-component yarn is kept under the predetermined tension during the thermal effect causing shrinkage. The measure of the shrinkage produced by the thermal effect is mechanically limited, so that the yarn is conveyed by the two yarn delivery drums, which are distanced from each other in yarn running direction. The thermal effect is caused in a yarn running path region, which lies between the yarn delivery drums.

Description

The The invention relates to a method for producing hosiery goods on a knitting machine, in which at least one in the knitted fabric Yarn is knitted by external action in its length permanently changeable.

There are yarns that, for example, under heat, shorten their length, ie shrink or extend. In the production of hosiery z. B. Two-component yarns used, which consist of a polyurethane core and a polyamide sheath enclosing this. In the heat treatment of such a yarn, the polyurethane component shrinks, so that the whole two-component yarn undergoes a volume effect in the form of a crimp. Embodiments of such yarns are in the EP 0 496 888 B1 described. In addition, there are two-component polyester filament yarns, the components of which have a different shrinkage behavior under heat, wherein a warm-stretched during manufacture component behaves as a so-called memory yarn with a self-elongation of up to 25%. When refining an article in which such a yarn is processed, the resulting length difference of the two components results in a so-called peach-skin effect. (See eg. "The India Textile Journal" December 2007, "New high-speed concept for making bi-shrinkage yarns" .)

Under Heat effect shrinking polyurethane yarns can also used as one-component yarns for special purposes which is equally hot-stretched Polyester yarns with self-elongation under heat applies. There are also a variety of one or more component yarns another type and materials, also under an outer Exposure, eg. A heat, a change in length Experienced. Multi-component yarns made of components that have a different Shrinkage or general length change behavior, especially under heat, can also be constructed so that one thread around another thread around looped or swirled with this. In the heat treatment arise volume effects, which are due to the fact that a the components in loop or loop form with the other Component is connected.

at the production of hosiery using a two-component yarn, at caused a ripple by heat can be, the yarn is knitted smooth, with the ripple only after completing the knitting process, d. H. in the refining of Raw product is triggered. This applies, for example, to the above-mentioned two-component yarn with a Polyurethane core and a polyamide sheath. Because the ripples only after the knitting is triggered, the goods must be very loose and considerably larger knitted are equal to the size of the finished product. By triggering the crimping in the finished knitted article, the yarn shortens considerably, which leads to a compression of the knitwear. The very loose However, knitted fabric in the raw material brings significant problems in the Production with itself, because this product is very sensitive to damage, especially so-called Zieher is. That means that yourself very easily pull individual threads out of the fabric which leads to a high reject rate.

task The invention is to remedy this difficulty and a To show the way, which allows to knit the raw material firmer, so that they are less sensitive to damage in the subsequent Finishing and processing operations.

to Solution of this task is the invention Method according to claim 1.

at The new procedure is such that by external Influence on its length permanently changeable Yarn on a yarn path from a spool or a cop to a knitting point the knitting machine is fed, the yarn on the Garnlaufweg is kept below a predetermined voltage and the triggering of the change in length of the yarn on the Garnlaufweg before its entry into the knitting point of the knitting machine he follows.

Dependent the volume effect sought and the type of processed accordingly Yarn, the yarn can be shrunk or lengthened. When Yarn, in a preferred embodiment, may be a multicomponent yarn be used, the at least one in their length permanently having changeable yarn component.

Thereby that the change in length of the yarn or the respective Yarn component, for example, in a Mehrkomponentengarn already on the Garnlaufweg is triggered before entering the knitting and while the yarn is held under such a yarn tension, that it is in spite of triggering the change in length can be properly entangled, can be a considerable knit firmer raw materials that are much less resistant to damage is more prone to do so than in a procedure is, in which the change in length of the yarn only in triggered a finishing step on the fabric of the raw material becomes.

For example in a two-component yarn of the aforementioned type with a polyurethane core and a polyamide sheath, the crimp becomes of the yarn, as mentioned, after knitting in conventional Way triggered by a heat treatment. It However, it was found that the crimp also caused by a stretching process. If the yarn on the Garnlaufweg before entering the knitting point For a short time stretched by about 25%, so this is the crimping already triggered in large part.

The Yarn can also travel through a heat treatment zone on the yarn path be carried out in which there is a heat effect is exposed to either the length change to be triggered solely by this heat treatment or the effect of stretching the yarn by applying it to improve and / or support heat.

To For this purpose, the yarn in the heat treatment zone the action of a jet of a gaseous heat transfer medium, eg. a jet of hot air. But it can also the yarn in the heat treatment zone over a heating element, for example a heating plate, are guided, or it may be a heated element wrapped in the yarn, be used in the form of a heating pin. Is the yarn through at least one yarn delivery device with a looped by the yarn Garnliefertrommel promoted to the knitting point, so may be the application of heat through a heated yarn supply drum the yarn delivery device take place.

The new process is basically for all yarns applicable, in which by means of heat and / or delay the properties can be modified. These are particular, however not exclusive, all types of yarn, in particular Filament yarns that consist of several components, the components during extrusion but also later by means of swirling, Twisting or winding are linked together. Also the so-called "differential shrinkage" - and The "Differential Shrinkage Elongation Yarns (DES)" can be processed like that.

further developments of the new method are the subject of subclaims.

In the drawing are embodiments of the article represented the invention. Show it:

1 in a highly simplified schematic representation of the Garnlaufweg between a cop and a knitting point of a knitting machine for carrying out an embodiment of the method according to the invention,

2 two yarn delivery devices of the device according to 1 in a schematic representation and in a side view,

3 the arrangement after 2 in a side view along the line III-III of 2 and in a schematic representation,

4 the arrangement after 2 , showing a modified embodiment of the yarn feeding devices in a corresponding schematic representation,

5 the arrangement after 4 in a side view along the line VV the 4 , and in a schematic representation,

6 a modified embodiment of the yarn delivery device of the arrangement according to 1 in a schematic side view and on a different scale and

7 the arrangement after 6 , in a side view and in a schematic representation.

In 1 is schematically the Garnlaufweg a yarn 1 between a cop 2 and a knitting station 3 an otherwise not shown knitting machine for the production of hosiery shown that the yarn 1 in a knit 4 incorporated.

The yarn 1 is a yarn in which by external action, ie in particular by heat and / or distortion, the properties can be permanently modified. By such an external action, the yarn can be shrunk in its length or lengthened, whereby a volume effect in the relaxed state can be achieved, in which the yarn, for example, undergoes a crimping or looping or looping. The yarn 1 may be one-component yarn or a multi-component, especially bi-component yarn. In the case of a multi-component yarn, it may be a yarn with a core and a sheath surrounding it or yarn structures in which individual components run next to each other, are twisted together and / or swirled or loop around each other. An example is the bi-component yarn with a polyurethane core mentioned at the outset and a polyamide (nylon 12) jacket enclosing it.

In the method according to the invention, the procedure is that the yarn 1 on his yarn walk from the Kops 2 to the knitting point 3 subjected to an external action that triggers the permanent modification of its properties. This external action consists in the embodiments described below of a stretching and / or heat treatment of the yarn. It is inventively before the inlet of the yarn 1 in the knitting area 3 instead of.

In the in the 1 to 7 Illustrated embodiments is the yarn 1 a two-component yarn having a core of polyurethane filament and a sheath of polyamide as mentioned in the foregoing. The yarn 1 becomes on the Garnlaufweg in the embodiment according to 1 over two in the yarn running direction 5 spaced yarn feeding devices arranged one behind the other 6 . 7 passed the yarn 1 promote at a different speed such that the yarn fervorrichtungen in one between the two Fadenlie 6 . 7 lying delay zone 8th is stretched. The warpage to which the yarn is subjected is typically between 20% and 30% of the original length, preferably about 25%. It has been found that this stretching in the polyurethane core of the yarn causes an initially latent shrinkage, which initially does not take effect on the yarn travel path, because the yarn passes through the two yarn delivery devices 6 . 7 is held under a predetermined yarn tension. The relaxation of the yarn takes place in the fabric at the stitch formation, so that the knitted fabric 4 a dense raw material formed by the desired curling effect of the yarn 1 is marked.

The two yarn delivery devices 6 . 7 are synchronized with the knitting machine, so that the yarn tension when entering the knitting point 3 and the warp in the draft zone 8th are kept constant. The two yarn delivery devices 6 . 7 can be of any type. It only has to be in the thread running direction 5 front yarn delivery device 7 the yarn 1 promote at a higher speed than that in Garnlaufrichtung 5 rear yarn delivery device 6 ,

In a non-limiting preferred embodiment, the yarn delivery devices 6 . 7 in each case a thread supply drum 9 on, that of the yarn to be conveyed 1 is wrapped in a conventional manner, wherein the yarn is still an axis-parallel guide pin 10 is guided around. The yarn on its circumference 1 substantially slip-free conveying yarn supply drums 9 have in the embodiments of the 1 to 4 each with the same diameter. The peripheral speed of the yarn supply drum in the direction of thread running 5 behind yarn delivery device, which is equal to the yarn entry speed V1 in the first yarn delivery device 6 is less than the peripheral speed corresponding to the outfeed speed V2 of the yarn 1 from the yarn delivery direction in front second yarn delivery device 7 , This discharge speed is equal to the entry speed in the knitting point 3 , In any case, V1 <V2.

While in the embodiment according to 1 the two yarn supply drums 9 , optionally from a common drive source, are driven individually, is in the embodiment according to 2 the arrangement made such that the two in the same direction circulating Garnliefertrommeln 9 through a belt drive 11 coupled with each other. The belt drive 11 has two pulleys 12 . 13 on, by a common drive belt 14 For example, in the form of a toothed belt are entwined and of which with the Garnliefertrommel 9 the yarn delivery device 7 firmly connected pulley 13 has a larger diameter than that with the Garnliefertrommel 9 the other yarn delivery device 6 non-rotatably connected pulley 12 , Of those by the belt drive 11 coupled to each other yarn supply drum 9 is driven by a not shown drive source synchronously with the knitting machine.

The embodiment according to the 4 . 5 corresponds to that after 1 with the difference that on the Garnlaufweg between the yarn supply drums 9 the two yarn delivery devices 6 . 7 the yarn 1 through a heat treatment zone 80 is carried out, in which the yarn is heated to a temperature sufficient for the modification of its properties, which is generally in the order of between 80 ° C and 130 °. The heat is supplied via a heating element, in this case by a heating plate 15 is formed, through which the yarn is passed and which, for example, is electrically heated.

Alternative to the heating plate 15 can the heat input to the yarn 1 also over a cylindrical heating pin 16 take place between the two yarn feeding devices 6 . 7 arranged looped by the passing yarn and in 1 indicated by dashed lines.

Another alternative way of supplying heat is in the 2 . 3 indicated. In this embodiment is on the between the two yarn feeding devices 6 . 7 continuous yarn 1 a ray 17 of a hot heat transfer medium, for example, a hot air jet directed from a nozzle arranged there 18 exit.

The heat effect on the yarn 1 before entering the knitting station 3 As a rule, in addition to the already described stretching between the two yarn delivery devices conveying the yarn at different speeds, V1 <V2 6 . 7 In order to thereby the effect of stretching and the resulting tripping example. the shrinkage of at least one yarn component to improve or support.

But there are also cases conceivable in which the triggering of the modification of the properties of the yarn 1 exclusively by supplying heat in the manner described. In these cases, the two yarn feeding devices promote 6 . 7 the yarn 1 each with the same speed, ie V1 = V2.

It is even possible to cause the shrinkage of the yarn solely by supplying heat and the distortion ratio of the two yarn feeding devices 6 . 7 to reverse the drawing, that is to say to operate the two yarn delivery devices with V1> V2, in order to obtain the lead in the yarn running direction 5 rear yarn delivery device 6 The yarn can be controlled to shrink, so that the shrinkage generated by the heat action is mechanically limited.

While in the described embodiments, the drawing of the yarn 1 by two separate, in the thread running direction 5 If the yarn delivery devices are arranged one behind the other, the process according to the invention can also be carried out with only one yarn delivery device 67 be done as in the 6 . 7 is illustrated. The yarn delivery device 67 has in this case two mutually coaxial and rotatably connected Garnliefertrommeln 9a . 9b on, on a common drive shaft 19 sit and thus revolve at the same speed. The thread delivery device 6 of the 2 corresponding yarn supply drum 9a thus promotes the incoming yarn with an inlet speed V1, which is smaller than the yarn outlet speed V2, the larger diameter yarn supply drum 9b , which of the yarn feeding device 7 equivalent.

Also in the embodiment of the 6 . 7 is a heat treatment of the passing yarn 1 possible. For this purpose, at least one of the yarn supply drums 9a . 9b be heated, which incidentally also in the embodiments of the 2 . 4 in terms of their thread supply drums 9 is possible or it may be the looped by the yarn deflection 10 be heated, which may be provided to the same extent for the aforementioned embodiments. Finally, the nozzle can 18 also in the embodiment according to the 6 . 7 be used, in which case the beam 17 the heat transfer medium on the yarn in the areas of the deflection pin 10 is steered.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• EP 0496888 B1 [0002]

Cited non-patent literature

• - "The India Textile Journal" December 2007, "New high-speed concept for making bi-shrinkage yarns" [0002]

Claims (21)

Method for producing hosiery on a knitting machine, in which at least one in the knitted fabric Yarn is knitted by external action in its length is permanently changeable, whereby the procedure involves the following steps: - Respectively of yarn on a yarn run path from a spool or a cop to a knitting point of the knitting machine, wherein the yarn on the Garnlaufweg is kept below a predetermined voltage and - Trigger the change in length of the yarn on the yarn path before entering the knitting station. Method according to claim 1, characterized in that that the yarn is shrunk to produce a volume effect. Method according to claim 1, characterized in that that the yarn is lengthened. Method according to one of the preceding claims, characterized in that a multi-component yarn is used as the yarn is that at least one in their length permanently changeable yarn components having. Method according to claim 2 or 4, characterized that the yarn is stretched on the Garnlaufweg, and by the drawing Garnelung or looping is triggered. Method according to claim 5, characterized in that that the yarn in the drawing by about 20 to 30%, in particular about 25%, is stretched. Method according to claim 5 or 6, characterized that the stretching of the yarn by two on the Garnlaufweg in Distance from one another arranged yarn delivery devices This takes the yarn at different delivery speeds promote. Method according to claim 7, characterized in that that yarn feeding devices used by the yarn are used entwined, driven Garnliefertrommeln have, with rotate around each other different peripheral speeds. Method according to claim 8, characterized in that that the yarn supply drums of the two yarn feeding devices with be driven from each other different speed. Method according to claim 2 or 4, characterized the stretching of the yarn by at least one yarn delivery device takes place, the at least one of the yarn looped thread supply drum having areas of mutually different diameter. Method according to claim 10, characterized in that that it has two yarn supply drums of different diameters, which are arranged coaxially with each other and at the same speed are driven. Method according to one of the preceding claims, characterized in that the yarn on the Garnlaufweg by a heat treatment zone is carried out in which it is exposed to heat. Method according to claim 12, characterized in that that the yarn in the heat treatment zone of the action a jet of gaseous heat transfer medium is suspended. Method according to claim 13, characterized in that that the yarn in the heat treatment zone over a heating element is guided. Method according to claim 14, characterized in that that as a heating element wrapped by the yarn heated element is used. Process according to claims 5 and 12, characterized characterized in that the yarn in addition to the drawing is subjected to a heat treatment. Process according to claims 7 or 10, characterized characterized in that the yarn has at least one heated Garnliefertrommel a yarn feeding device is performed. Process according to claims 7 and 12, characterized characterized in that the yarn fervorrichtungen in one between the two Garnlie lying stretching region subjected to heat becomes. Process according to claims 4 and 12, characterized characterized in that the multi-component yarn during the a shrinkage effecting heat action under a predetermined voltage is maintained. Method according to claim 19, characterized that the measure of the by the heat effect produced shrinkage is mechanically limited. Method according to claim 20, characterized in that that the shrinkage is limited by the fact that the yarn two rotating at different peripheral speed, in Garnlaufrichtung spaced apart and entwined by the yarn Garnliefertrommeln is promoted, and the heat is effected in a Garnlaufwegbereich, the between the two Garnliefertrommeln lies.