WO2007009666A1 - Roving bobbin - Google Patents

Abstract

The invention relates to a roving bobbin, particularly a cross-wound bobbin, comprising a roving made of synthetic fibers to be further processed into a yarn. The roving is wound onto the roving bobbin to form a staple sliver, the fibers of the stable sliver being arranged, in essence, with a parallel orientation to one another without almost any twisting.

Description

 Vorqarnspule

The invention relates to a roving bobbin with a roving, in particular for a ring spinning machine or a twisting machine. The roving is made from at least one fully drawn semifinished product which is in multifilament form, wherein the semifinished product is fed to at least one stretch breaking zone, and a tear conversion of the semi-finished product in the stretch breaking zone into a staple fiber strip is carried out.

The invention is in the field of making staple yarn from filament yarns, which may be pure staple synthetic yarn or mixed yarn of synthetic and natural fibers. The filament yarns used for this purpose are semi-finished products that are not yet suitable for the production of textiles, since a fabric made from them would not have the desired properties. The development in staple fiber spinning is characterized by the idea that both natural fibers such as cotton and wool as well as synthetic fibers can be processed with the same technology. This idea forms the basis for the production of blended yarns in addition to the staple yarns of 100 percent synthetic or natural fibers. For the production of blended yarn it is necessary that the synthetic fibers used for this purpose can be adapted as closely as possible to the naturally prescribed properties of the natural fibers with regard to distribution of the fiber length, force / elongation ratio, fineness and crimp. The factors mentioned also determine important production parameters and yarn properties, such as irregularity of the yarn, number of fibers in the yarn cross section and yarn count. For this purpose, the synthetic fibers of the filament yarns can be torn in a stretch-breaking machine, wherein the stretch-breaking machine with LOY (Low Oriented Yarn), ie low-oriented filament yarns, POY (Partially Oriented Yarn), ie partially oriented filament yarns or FOY (Fuji Oriented Yarn), so completely oriented Filament yarns, can be fed and the result of

Yield strain is formed by a roving. This roving is a staple fiber ribbon, which is processed directly. The roving is e.g. spun in a ring spinning process and solidified into a yarn. The starting material for feeding the stretch breaking machine is a semi-finished product consisting of a plurality of filaments.

EP 1 522 614 A1 discloses a machine in which a number of at least one, usually up to eight, filament yarns are withdrawn from supply spools in a gate. The tension of the filament yarns can be monitored and controlled to a constant value if the quality of the supply bobbins is very poor or the supply bobbins are different (for example, with regard to feed bobbin end titer, number of filaments, color of the supply bobbins). Voltage regulation is optional and depends on the feed bobbins. The filament yarns are brought together to form a filament yarn F, and this passes into a draw zone SZ formed by two conveyor rolls, which feeds to the

Orientation of the fibers is required. If the final product, ie the staple yarn, is to have at least a partial orientation of the fibers, partial stretching of the filament yarn is required, and if the end product is to have complete orientation of the fibers, complete stretching of the filament yarn F is required. In contrast, an end product with a low orientation of the fibers does not require stretching. The first roller initiates the stretching process and optimizes the stretching forces, and the second roller causes the stretching process via its higher peripheral speed compared to the first roller. The rollers can be heated, whereby a fixation of the Filament yarn F is achieved, which is an essential requirement for high-speed spinning. Subsequently, the filament yarn F enters a cooling zone with an optional cooling device, in which it is cooled from the temperature of the heated rolls to ambient temperature. The cooling device is very important when producing at very high speed, at low speed the filament yarn F can be cooled in the cooling zone without a cooling device. This means that the use of the cooling device depends on the production speed and the temperature of the rolls. After the cooling zone, the filament yarn F passes through at least two spaced rollers each consisting of a conveying roller and one or two

Pressure rollers exist. The rollers form e.g. three stretch breaking zones SB1 to SB3. The foremost one in the yarn running direction is driven at a higher speed than the downstream ones, whereby a tensile force is applied to the filament yarn in each stretch breaking zone SB1 to SB3. The length of the first stretch breaking zone SB1 is greater than the length of the second break breaking zone SB2 and its length is greater than that of the third drawing breaking zone SB3.

In the first stretch breaking zone SB1, all the filaments of the filament yarn F are torn and thereby converted into fibers. By changing the ratio of the speed of the rolls, it is possible to reduce the yarn count to the desired dtex value (dtex = decitex, which is the weight in grams per 10 ¹ 000 meter of yarn). The optional second and third stretch breaking zones SB2 and SB3 serve to further partially refract the now fibers and to reduce the variation in fiber length and number of fibers in the yarn cross section.

In WO-A-00/77283, said stretch breaking process is described in detail. In English, the second or third stretch break (stretch breaking zone SB2 or SB3) is often referred to as "rebreaking". By the stretch breaking process, the filaments of the filament yarn F become one converted staple fiber ribbon existing relatively loose fibers, which is solidified (consolidated) following the break-breaking to a holding stacking yarn. By this solidification, which takes place for example through a nozzle, we obtain a staple G with the desired optical and physical properties and the desired handle. The solidification stress required for the consolidation of the sliver to the staple yarn G is generated by a draw roll.

From US 2004/028896 A1, US 4 837 117 A and US 4 080 778 A further yarn production processes are known. The yarns produced according to these documents are further processed directly in web processes. The fibers of the yarn of US 4 080 778 A are intertwined by means of a nozzle.

In the case of US 2004/028896 A1 and US 4,837 117 A is in each case a

Carbon fiber yarn produced. These carbon fiber yarns are finished yarns that are used directly for weaving processes. The carbon fiber yarns are therefore not as a wound on a bobbin rovings of a yarn, but as a finished yarn before.

Thus, a finished yarn is always produced with the aforementioned yarn production machines or yarn production methods. For this purpose, as a completion of the manufacturing process, a permanent solidification of the existing during the manufacturing process roving is made to then wind the finished yarn on a yarn package. The yarn always has a tensile strength of at least 20 centinewtons per tex. A disadvantage of the known yarn-forming machines with stretch breaking zones is that the integration of various yarn finishing processes, such as ring spinning or twisting, results in an uneconomic yarn production process, since such yarn finishing processes have significantly lower production speeds than the stack yarn production itself. For such Garnveredelungsprozesse the roving used for this purpose must have the lowest possible strength, since it still has to be warped in these processes, ie the individual fibers of the roving must be able to easily slip past each other under tension. However, the solidified staple yarn is no longer suitable as a template yarn, ie, as a starting product for these processes, since such a consolidated yarn is no longer sufficiently stretchable. If one integrated the yarn finishing processes within one of the described yarn manufacturing machines, then the entire manufacturing process would have to proceed at the lower production speed, whereby the staple yarn production machine would not be utilized economically.

The invention has for its object to provide a roving bobbin with a roving, which avoids the disadvantages of the prior art and in particular can be produced while maintaining a high production speed of a staple yarn and as a supply spool for the production of finished yarns with lower production speeds, such as. Twisted yarn, suitable as staple yarn.

This object is achieved by the roving bobbin of the independent claim. The dependent claims represent preferred embodiments of the invention.

In an inventive, in particular by the method described below, roving with a roving of synthetic fibers, such as fibers of polyamide or polyester, ie a polymer, for further processing into a yarn, the roving is wound as a staple fiber ribbon on the roving, the fibers of Staple fiber ribbon substantially parallel to each other almost without rotation are arranged against each other. Thus, a roving of a yarn is wound up. The roving is unbonded, ie the fibers of the roving are not spun together or eg by means of a Resin glued together. The wound roving is suitable only after solidification to a yarn for further processing in a textile manufacturing process, such as a weaving or knitting process. The individual fibers of the roving can easily slide past each other, whereby the use of the yarn package according to the invention directly in such a textile manufacturing process would directly lead to yarn breakage of the roving. Under almost torsion-free is to be understood that a rotation of the fibers of the stacking tape, if present, corresponds to a rotation of the fibers of the semifinished products used as the starting material in the described manufacturing process, ie no significant additional rotations is present. In particular, a possibly present minimum twist has no significant influence on the strength of the roving for the stretchability of the roving. Advantageously, this is a cross-wound bobbin. Characterized in that the roving is wound on a spool, it can serve as a supply spool without affecting in particular the production speed of the roving for slower follow-up processes on the spool. It is thus a particularly economical production of staple yarns with a true twist, for example by means of a ring spinning machine or a twisting machine allows.

For further processing into fine yarns, the individual fibers of the staple fiber band preferably have a fineness of 0.3 to 5 decitex.

If the roving has a fineness of less than 150 tex, the roving can be particularly well wound up on a cross-wound bobbin.

The roving bobbin according to the invention is preferably produced by the method described below for producing a roving on a roving bobbin. The feed bobbin according to the invention is particularly suitable as a supply bobbin for a ring spinning machine or a twin machine. In which The process consists of at least one completely drawn multifilament-shaped semi-finished product after feeding the semifinished product into at least one stretch breaking zone and a break conversion of the semi-finished product in the stretch-breaking zone into a staple fiber ribbon, the roving bobbin being wound up as a staple fiber ribbon Roving on the Vorgamspule created.

The invention is based on the finding that, although the staple fiber tape is not solidified, and thus the individual fibers can easily slip past each other under tension, it is possible to wind the unconsolidated stacking tape on a spool. As a result, the roving thus produced can be produced at a high production speed and kept in a follow-up process on another machine as a template material for a slower running yarn finishing process. Thus, the economical operation of the stretch breaking process is possible even if e.g. a

Ring spinning machine or a twisting machine to be equipped with the thus created roving. In the staple fiber ribbon, the fibers are in a substantially parallel orientation so that the roving is still stretchable. The coiled roving or staple fiber band is not, in particular by a nozzle applying a torque to the staple fiber band, e.g. a

Air texturing nozzle, solidified under a solidification stress, i. consolidated into a staple yarn. Thus, the roving bobbin produced according to the invention is a wound roving with a low strength and essentially without a twisting of the fibers of the stacking band against each other.

In order to achieve uniform production conditions and in particular a uniform winding of the roving onto the roving bobbin, the staple fiber band preferably passes through a conveying device before being wound up. The latter is particularly advantageous when a cross-wound bobbin is created as a roving bobbin. A cheese is less susceptible to damage than a coil on which the roving is wound only in parallel windings. As a result, such a coil is transport stable. A cheese can also with a

Thread reserve can be used as a supply spool. In such an application, a quasi-endless manufacturing process with such a supply bobbin is possible if the thread reserve is connected to a connecting coil.

Particularly preferably, the staple fiber ribbon is temporarily stabilized before being wound up. By temporary it is meant that the stabilization is no longer present in the roving wound on the roving bobbin, i. E. either dissolved itself without further measures or was actively dissolved again. This makes it possible to achieve higher production speeds, since the temporary stabilization of the staple fiber band in areas of its yarn path where a special mechanical stress occurs, e.g. on thread guides or the described conveying device is less stretched and thus lower quality impairments or production interruptions occur by thread breaks.

The temporary stabilization can be advantageously carried out by applying a torque to the staple fiber ribbon through a nozzle, wherein a twisting of the fibers of the staple fiber ribbon by the torque is dissolved before winding again. With an appropriate arrangement of the nozzle in the yarn path, the rotation of the fibers will automatically dissolve again, since a fixation of the rotation, eg by a following to a heating zone cooling zone in the yarn path, is omitted. Preferably, the semifinished product is made from a partially or slightly oriented yarn, wherein the oriented yarn is fed to a draw zone and drawn in the draw zone to the semifinished product. As a result, the completely drawn yarn which is required as the starting product of the process described for producing the roving bobbin according to the invention can be provided. It is then not a FDY used as a template but a POY, for example. The POY is stretched in-line, ie as a partial process step of the process, in a draw zone, in an upstream stage on the roving production machine with which said method is carried out, to form a FDY, ie the completely drawn semifinished product.

The semifinished product preferably passes through a cooling zone between the draw zone and the stretch break zone. This allows a very high production speed.

A roving production machine, which is set up to carry out the described method, has at least one machine position designed as a stretch breaking zone, wherein the stretch breaking zone is formed by individually drivable rolls. In this case, a winding unit is provided on the roving production machine, designed to create a roving bobbin, preferably a cross-wound bobbin, by winding up a roving present as a staple fiber band after the stretch breaking zone. In this roving production machine can be provided in an advantageous manner in particular provided for tear conversion machine parts, as described in the prior art. In particular, several stretch breaking zones can advantageously be arranged one behind the other and / or it can be provided that the roving production machine is set up for the simultaneous feeding of a plurality of filament yarns as semi-finished products into the stretch breaking zones. With the Vorgarnherstellungsmaschine a roving bobbin can be made with a roving present as a staple fiber ribbon, whereby the described advantages can be achieved.

Preferably, between the stretch breaking zone and the winding unit is a

Conveying device provided, adapted to promote the staple fiber ribbon with a preferably controlled thread tension to Aufspuleinheit. This makes it possible to produce a more even roving quality.

In particular, it is particularly preferred between the stretch breaking zone and the

Winding unit provided a stabilizing device to temporarily stabilize the staple fiber tape. Faulty production stoppages, e.g. By thread breaks on thread guides or the conveyor, are minimized.

The stabilizing device may advantageously have a nozzle, configured to carry out the temporary stabilization by applying a torque to the staple fiber ribbon, wherein a twisting of the fibers of the staple fiber ribbon by the torque dissolves before winding again. By means of the nozzle, the temporary stabilization can be achieved in a proven manner. The twist dissolves in the further threadline by itself again, since no fixation of the rotation is made.

A roving bobbin, in particular a cheese, with a roving made of synthetic fibers for further processing into a yarn is proposed. The roving is wound as a staple fiber ribbon on the roving bobbin, wherein the fibers of the staple fiber band are arranged substantially parallel to each other in almost no rotation against each other. The invention is not limited to the embodiments given above. Rather, a number of variants are conceivable, which make use of the features of the invention even with fundamentally different type of execution. In particular, the different illustrated features of the invention can be combined with the features of the cited prior art, provided that no final consolidation of the Vorgans before being wound onto the roving bobbin.

Claims

claims 1. roving bobbin, in particular cross-wound bobbin, with a roving of a synthetic fiber yarn unrolled on the roving bobbin so that it does not harden Further processing into a yarn, wherein the roving is wound as a staple fiber ribbon on the roving bobbin, and wherein the fibers of the staple fiber ribbon are arranged substantially parallel to each other in almost no rotation against each other. 2. roving bobbin according to claim 1, characterized in that the individual fibers of the staple fiber ribbon have a fineness of 0.3 to 5 Dezitex. 3. roving bobbin according to at least one of claims 1 to 2, characterized in that the roving has a fineness of less than 150 tex.