EP3596261A1

EP3596261A1 - Method and device for producing turf yarns for artificial turfs

Info

Publication number: EP3596261A1
Application number: EP18714135.3A
Authority: EP
Inventors: Jens Weinhold; Frank Heymann; Bert Wöllner; Kenneth Schindler
Original assignee: STC Spinnzwirn GmbH
Current assignee: STC Spinnzwirn GmbH
Priority date: 2017-03-15
Filing date: 2018-03-06
Publication date: 2020-01-22
Also published as: WO2018166837A1

Abstract

The invention relates to a method and a device for producing turf yarns for artificial turfs. A plurality of monofilaments or strips are drawn together in the form of a fiber bundle after extruding a polymer melt and are stretched by multiple rollers. The fiber bundle is separated into a plurality of turf yarns with a respective group of strips or monofilaments and is crimped prior to being wound in order to form a coil. The aim of the invention is to allow a process which is as compact as possible. According to the invention, this is achieved in that the turf yarns are formed immediately after the stretching process and are crimped in a parallel manner next one another prior to being separated.

Description

Process and device for producing grass yarns for artificial turf

The invention relates to a process for producing grass yarns for artificial turf according to the preamble of claim 1 and to a device for producing grass yarns for artificial turf according to the preamble of claim 6.

A generic method and a generic device for the production of grass yarns for artificial grass, for example, from WO 201 1/020706 A 1 show.

In the production of artificial grass so-called grass yarns are used, which have a composite of several monofilaments or multiple tapes. The grass yarn is processed into a synthetic turf carpet in a tufting process. Here are the artificial fibers of the grass yarn as possible properties of the natural grasses replicate. It is known, for example, to influence the cross sections, coloring and the structure of the monofilaments or ribbons in accordance with the natural grasses. In particular for structural adaptation, the monofilaments or ribbons are provided with a crimp.

In the known method and in the known device for this purpose, the monofilaments or tapes are separated after the extrusion process and merged to form the grass yarn in groups of four to ten tapes or monofilaments. Immediately before winding, a crimping of the fibers of the grass yarn takes place, for which purpose a plurality of crimping units are assigned to the winding positions. However, it has been found that intensive crimping of the fibers is particularly which can be produced on previously heated monofilaments or ribbons. In that regard, it is common practice to heat the fibers of the grass yarn by, for example, heated godets. In that regard, the winding stations contain a plurality of heating means in order to heat the fibers combined in the grass yarns in front of the herb.

It is an object of the invention to develop the generic method and the generic device for producing grass yarns for artificial turf so that on the one hand as uniform as possible ripple grass yarns can be produced and on the other hand, a very compact process control is possible.

This object is achieved by a method with the features of claim 1 and by a device having the features of claim 6.

Advantageous developments of the invention are defined by the features and feature combinations of the respective subclaims. The invention is characterized in that the formation of the grass yarns is laid in the extrusion process. Thus, the grass yarns can be formed immediately after stretching the fiber sheet of the tapes or monofilaments and are crimped parallel to each other prior to separation. For this purpose, the crimping units of the stretching device are arranged in such a way that the grass yarns form prior to separation. The shift in the formation of the grass yarns within the extrusion process also offers the great advantage that each of the grass yarns has substantially the same characteristics, since the paths of the individual monofilaments or ribbons are identical. So the fiber share of the bands or Monofilaments are divided directly at a position within the fiber run parallel to the grass yarns and then crimped directly. The invention was not suggested by the known method and the known apparatus for producing grass yarns from WO 2010/102921 AI. The grass yarns are in this case produced from tapes or monofilaments of two separate extrusion processes, with a complete fiber bundle of one of the extrusion processes after stretching being given a crimped structure. In that regard, when separating grass yarns are formed, which consist of crimped and uncrimped fibers. In contrast, the invention has the advantage that the fibers of the grass yarns are crimped as a composite. Thus, a relatively stable structure of the grass yarn is achieved even before separation. By the method known from WO 2010/102921 Al, it was not obvious to lay the formation of the grass yarns in the extrusion process. In addition, the known device, in which a fiber bundle is guided band-shaped by two rollers in a compression chamber, completely unsuitable to curl separate grass yarns.

The invention offers the advantage of producing the fiber composite of the grass yarns with a uniform and uniform crimp structure.

In order to be able to use directly the heating generated in the bands or monofilaments during drawing, the method variant in which the fiber bundle is heated to stretch and in which the grass yarns formed after drawing are uncooled is particularly advantageous. In that regard, the heat of stretching is used on the fibers of grass yarns to obtain an intense crimp. These advantages can be realized in particular by the device variant in which the stretching device is associated with a heating device for controlling the temperature of the fiber bundle, wherein the curling units are arranged directly on a discharge side of the drawing device.

In order to obtain a cohesion of the individual fibers within the grass yarn, the method variant has been proven in which the grass yarns are crimped separately by several delivery nozzles in several compression chambers to Garnstopfen and in which the Garnstopfen for cooling parallel to a rotating cooling drum or be stored directly on a conveyor belt. By the fluid streams of the delivery nozzles, the fibers of the grass yarns can be promoted to the Garnstopfen with intense forfeiture. Such entanglements increase the cohesion of the individually crimped fiber even after dissolving the yarn plug. For intensive cooling, there is also the possibility that the cooling drum is arranged directly upstream of the conveyor belt.

To dissolve the Garnstopfens is provided that the Garnstopfen be performed on the cooling drum and / or the conveyor belt at a distance side by side and dissolved after cooling by a partial looping on a dissolving bar or an opening roller to the crimped grass yarns. Subsequently, the crimped grass yarns can be separated directly to be wound into coils in the winding stations. For this purpose, the grass yarns are pulled off directly after crimping through several godets separately and fed to the individual winding stations. Alternatively, a plurality of opening rollers may be provided, which are arranged upstream of the winding points for supporting separation of the grass yarns. For the crimping of the grass yarns, the development of the device according to the invention is preferably used, in which the crimping units are formed by a plurality of delivery nozzles and a plurality of stuffer box, which are held in a row arrangement parallel to a discharge roller of the stretching device. Thus, the fiber bundle can be split immediately after expiration of the stretching device to the grass yarns and fed to the crimping units.

In order to obtain a very compact process control of the fiber bundle and the grass yarns, the development of the device according to the invention is preferably carried out, in which the stuffer boxes for storing Garnstopfen a cooling drum and / or a conveyor belt is assigned that at least partially below several draw rolls of Stretching extends. Thus, a cooling of the Garnstopfen immediately after the crimping is possible. Due to the low height expansion of the conveyor belt, a high degree of integration can be achieved directly within the drafting device.

In order for the yarn plugs emerging through the stuffer boxes to be placed as compactly as possible on the surface of the conveyor belt under the entrained air flow, it is further provided that the conveyor belt in the area of the stuffer boxes is assigned a storage table with several troughs, the troughs each having an outlet of the stuffer box are assigned and form a passage to the conveyor belt. So The yarn plugs in the troughs can be guided through the conveyor belt.

Likewise, the cooling drum has a plurality of troughs on the perimeter for secure reception and guidance of the yarn plugs.

The yarn plugs are advantageously dissolved by the development of the device according to the invention, in which the conveyor belt is assigned to a discharge side of a dissolving bar or a rotatable dissolving roller which extends transversely to the conveyor belt. The forced wrapping on the disintegrating bar or roller causes the yarn plug to disintegrate and the crimped grass yarn to be peeled off for separation.

In this case, a plurality of opening rollers can be used, which are arranged directly upstream of the winding points to support the separation.

As an alternative or in addition to the opening rollers, the separating device has a plurality of godets which are arranged upstream of the winding points and which each remove one of the grass yarns after the curling from the conveyor belt.

The method according to the invention will be explained in more detail below with reference to some embodiments of the device according to the invention with reference to the accompanying figures.

They show: Fig. 1 shows schematically a view of an embodiment of the device according to the invention

2 schematically shows a detail view of the crimping units in the region of the stretching device of the exemplary embodiment according to FIG. 1

3 is a schematic side view of the crimping units from FIG. 2

4 is a schematic plan view of the crimping units of FIG. 2

Fig. 5 shows schematically a view of another embodiment of the device according to the invention

Fig. 6 shows schematically a side view of the crimping unit of Figure 5

Fig. 7 shows schematically a plan view of the crimping unit of Figure 5.

In Fig. 1, a first embodiment of the inventive device for producing grass yarns for an artificial turf is shown schematically schematically. The exemplary embodiment has an extrusion device 1 for producing a multiplicity of monofilaments from a thermoplastic material. In this example, the extrusion device 1 has an extruder 2, which is connected to an extender head 3. The Extmsionskopf 3 is assigned a cooling bath 4. On the outlet side of the cooling bath 4, a diverter 5 is arranged with a plurality of deflection rollers, on whose circumference the monofilaments are guided with simple looping. The deflection 5 is usually combined with an exhaust to receive the adhering to the monofilaments cooling liquid of the cooling bath 4. To pull off the monofilaments, a draw-off device 6 is provided, which cooperates with a stretching device 9 in order to draw the monofilaments guided as a fiber bundle 8. The draw-off device 6 has for this purpose a plurality of draw-off rollers 6.1 and the stretching device 9 a plurality of draw rolls 9.1. Between the take-off device 6 and the stretching device 9, a heating device 7 is provided, through which the fiber bundle 8 is heated. The heating device 7 could be formed for example by a convection oven, in which the monofilaments are heated to a stretching temperature. For drawing the fiber share, the take-off rolls 6.1 and the draw rolls 9.1 are driven with a speed difference.

Within the stretching device 9, a plurality of crimping units 10 are arranged below the stretching rollers 9.1. The crimping units 10 cooperate with a conveyor belt 12 which extends at least partially below the drafting rollers 9.1. To explain the crimping units 10 of the conveyor belt 12, reference is made to FIGS. 2 to 4 in addition to FIGS. 2, the crimping units 10 from the embodiment of FIG. 1 are shown in detail. FIG. 3 shows the crimping devices 10 from the exemplary embodiment according to FIG. 1 in a side view, and FIG. 4 shows a plan view of the crimping device 10. Unless expressly made to any of the figures, the following description applies to all figures.

The crimping units 10 are arranged in a row-shaped arrangement parallel to the drafting rollers 9.1. Each of the crimping unit 10 is hereby formed by a delivery nozzle 10.1 and a stuffer box 10.2. The delivery nozzle 10.1 is coupled to a compressed air source, not shown here. The delivery nozzles 10.1 open directly into the stuffer box 10.2. The compression chambers 10.2 are associated with an outlet of the conveyor belt 12. In this case, the free ends of the compression chambers 10.2 protrude into a respective raceway groove 16 of a delivery table 15. The delivery table 15 is arranged at a short distance above the conveyor belt 12 and extends over a partial length of the conveyor belt 12. The conveyor belt 12 is driven by a plurality of conveyor rollers 12.1.

To divide the fiber bundle 8 into several grass yarns 1 1, each of the crimping units 10 is preceded by a deflection roller 14. Via the deflection rollers 14, a group of monofilaments is picked up and fed into the crimping units 10 as grass yarn 11.

The yarn plugs 13 formed by the crimping units 10 are deposited on the surface of the conveyor belt 12 by the stuffer boxes 10. The conveyor belt 12 conveys the Garnstopfen 13 to a drain side. On the discharge side of the conveyor belt 12 a Auilösestange 17 is provided, on whose circumference the Garnstopfen 13 are guided with a Teilumschlingung. As an alternative to the Auilösestange 17 the conveyor belt 12 could be associated with a freely rotatable take-up roller. The dissolving roller could be held in contact with the conveyor belt.

As is apparent from the illustration in Fig. 1, the Auilösestange 17 is a separating device 18 downstream to separate the parallel guided grass yarns 1 1 and to separate. For this purpose, the separating device 18 has a guide bar 18.1 and a plurality of godets 18.2. The godets 18.2 are each preceded by a winding point 19, in which the crimped grass yarns 1 1 are wound into a coil 20. The winding stations 19 are placed side by side to a machine longitudinal side for this purpose. In the exemplary embodiment illustrated in FIG. 1, a polymer melt is produced via the extruder 2 and extruded via the extrusion head 3 into a multiplicity of monofilaments. The monofilaments are cooled in the cooling bath 4 and withdrawn as a fiber bundle 8 through the draw-off rollers 6.1 of the discharge device 6. The monofilaments are guided over the deflection 5 for stripping the cooling liquid.

From the discharge device 6, the fiber bundle 8 passes into a heating device 7 and is heated to stretching to a stretching temperature. In this case, a differential speed is set between the stretching device 9 and the take-off device 6, so that the drafting rollers 9.1 are operated at a higher circumferential speed than the take-off rollers 6.1.

After expiry of the fiber bundle 8 from a last draw godet 9.1, the monofilaments are brought together in groups to form a grass yarn 1 1 via the deflection rollers 14 and the crimping units 10. Each of the grass yarns 1 1 is conveyed via the delivery nozzles 10.1 to a yarn plug 13 in the connected compression chambers 10.2. In this case, the fiber bundle 8 is fed directly to the crimping units 10 directly on the discharge side of the stretching device 9 without cooling. This results in a residual heat contained by the drawing on the monofilaments, which is advantageously used for curling the grass yarns 1 1. The heated Garnstopfen 13, which can be formed with a hot fluid or a cold fluid are deposited on the surface of the conveyor belt 12 and cooled to the environment. At the end of the conveyor belt 12, the Garnstopfen 13 are guided around the Auflösestange 17 and each deducted by one of the godets 18.2. For this purpose, the godets 18.2 are preferably combined with a deflection roller in order to obtain a sufficient tensile force for pulling off the respective grass yarn via multiple wrapping. The separated grass yarns 1 1 are then fed to the winding stations 19 and wound in each case to the coil 20. For thread guidance, the winding stations 19 have, for example, a dancer arm control, a traversing device and a pressure roller. In the embodiment shown in Fig. 1, the grass yarns 1 1 are formed by a fiber bundle 8 of a plurality of monofilaments. In principle, however, it is also possible to form the grass yarns 1 1 of several groups of bands. For this purpose, the extrusion head 3 would be used to extrude a film. The film would be cooled via the cooling bath 4 and cut by a cutter 21 into a plurality of belts. For this purpose, the cutting device 21 is arranged, for example, in a dashed representation between the deflection mechanism 5 and the extraction device 6. The further course and treatment of the bands would be identical to the embodiment according to FIG. 1.

In the embodiment illustrated in FIG. 1, the monofilaments or ribbons are extruded from a polymer material. In principle, however, it is possible to extrude polymer materials based on a polymer in respectively different colors or even different polymer materials of different polymers to extrude. For this purpose, the extruder head 3 would be connected to two separate extruders 2. In Fig. 1, a second extruder is shown in dashed lines. FIG. 5 diagrammatically shows schematically another embodiment of the device according to the invention for producing grass yarns for an artificial turf. The exemplary embodiment is essentially identical to the exemplary embodiment according to FIG. 1, so that only the differences are explained at this point and reference is made to the aforementioned description to avoid repetition.

In the embodiment of Fig. 5, the crimping units 10 cooperate with a cooling drum 22 which extends below the drafting rollers 9.1. Below the cooling drum 22, a conveyor belt 12 is arranged, which has a width corresponding to the length of the cooling drum 22. The conveyor belt 12 extends from the stretching device 9 up to a plurality of winding points 19. Each winding point 19 is associated with the conveyor belt 12 each have a Auilöserolle 17.1. The Auilöserollen 17.1 cooperate with a separating device 18 to dissolve the run on the surface of the conveyor belt 12 yarn plug 13 to each grass yarn 1 1 and to separate, so that each of the grass yarns can be wound separately to a coil 20 in the winding points 19. The separating device 18 has for this purpose a plurality of godets 18.2. To explain the crimping units 10 and the cooling drum 22, reference is made to FIGS. 6 and 7 in addition to FIGS.

FIG. 6 shows the ruffling units 10 from the exemplary embodiment according to FIG. 5 in a side view and in FIG. 7 in a plan view. provides. Unless expressly made to any of the figures, the following description applies to all figures.

The crimping units 10 are also arranged here in a row-like arrangement parallel to the draw rolls 9.1. Each of the crimping units 10 is formed by a delivery nozzle 10.1 and a stuffer box 10.2. The compression chambers 10.2 are assigned to the circumference of the cooling drum 22 with an outlet. In this case, the free ends of the compression chambers 10.2 protrude into a respective raceway groove 16 on the circumference of the cooling drum 22. The cooling drum 22 is driven by a drive 22.1 for receiving the yarn plugs 13 delivered by the compression chambers 10.2. The cooling drum in this case has a gas-permeable jacket in the grooves 16 to suck in a cooling air via a vacuum within the cooling drum 22 and thereby cool the yarn plugs 13.

Below the cooling drum 22, the conveyor belt 12 is arranged, which is driven by a plurality of conveyor rollers 12.1 for transporting the Garnstopfen 13. The yarn plugs 13 are deposited by the cooling drum 22 on the surface of the conveyor belt 12. The peripheral speed of the cooling drum 22 is preferably equal to a transport speed of the conveyor belt 12. Basically, however, speed differences can be adjusted.

The conveyor belt 12 extends to the winding stations 19, wherein a winding roller 17.1 for dissolving the yarn plugs 13 is arranged per winding point 19 above the conveyor belt 12. This results in the same conditions at each winding point 19, since the yarn plug 13 is tension-free on the conveyor belt 12 and a pickup point to the coil 20 in each winding point 19 has equal lengths. The embodiment of Figure 5 is thus particularly suitable for making a variety of crimped grass yarns having substantially identical physical properties.

The inventive method and apparatus according to the invention are basically suitable for processing all conventional thermoplastic materials into a grass yarn. In particular, however, the materials such as PP, LLDPE, HDPE or PA have been proven. These polymers can also be extruded into a film by means of coextrusion in combination.

Claims

claims

1 . A method for producing synthetic grass grass yarns comprising the step of pulling a plurality of ribbons or monofilaments together after extrusion of a polymer melt as a fiber bundle and drawing it through a plurality of rolls wherein the fiber bundle is divided into a plurality of grass yarns each having a group of ribbons or monofilaments is separated and in which the grass yarn is crimped before being wound into a coil, characterized in that the grass yarns are formed immediately after stretching and are crimped parallel to each other prior to separation. 2. The method according to claim 1, characterized in that the fiber sheet is heated for stretching and that the grass yarns formed after stretching are curled uncooled.

A method according to claim 2, characterized in that the grass yarns for crimping are separately conveyed through several delivery nozzles in several compression chambers to Garnstopfen and that the Garnstopfen are stored for cooling in parallel on a cooling drum and / or a conveyor belt. 4. The method according to claim 3, characterized in that the yarn plugs are guided on the cooling drum and / or the conveyor belt at a distance side by side and after cooling by a partial lumschlingung on a dissolving bar or opening roller to the crimped grass yarns are dissolved. Method according to one of claims 1 to 4, characterized in that the grass yarns are separated separately for separation after crimping by a plurality of godets and are wound up by a plurality of winding stations separately to coils.

Device for producing synthetic grass grass yarns having an extrusion device (1) for producing a plurality of tapes or monofilaments, having a take-off device (6) for pulling off the tapes or monofilaments as a fiber bundle (8), with a stretching device (9) for stretching the fibers A fiber bundle (8), comprising separating means (18) for separating the fiber bundle (8) into a plurality of grass yarns (1 1) each having a group of ribbons or monofilaments, a plurality of curling units (10) and a plurality of winding stations (19) for separately winding the grass yarns (1 1) into bobbins (20), characterized in that the crimping units (10) are associated with the stretching device (9) in such a way that the grass yarns (11) form prior to separation.

Apparatus according to claim 6, characterized in that the stretching device (9) is associated with a heating device (7) for tempering the fiber bundle (8), wherein the crimping units (10) are arranged directly on a discharge side of the stretching device (9).

Apparatus according to claim 6 or 7, characterized in that the crimping units (10) by a plurality of delivery nozzles (10.1) and a plurality of compression chambers (10.2) are formed, which are held in a series arrangement parallel to a draw roller (9.1) of the stretching device (9). Apparatus according to claim 8, characterized in that the stuffer boxes (10.2) for storing Garnstopfen (13) is associated with a cooling drum (22) and / or a conveyor belt (12), at least partially below a plurality of draw rolls (9.1) of the stretching device ( 9).

10. The device according to claim 9, characterized in that the conveyor belt (12) in the compression chambers (10.2) is assigned a storage table (15) with a plurality of troughs (16), the troughs (16) each having an outlet of the compression chambers (10.2 ) and form a passage to the conveyor belt (12).

1 1. Apparatus according to claim 9 or 10, characterized in that the cooling drum (22) at the periphery a plurality of troughs (16), which are each associated with an outlet of the compression chambers (10.2).

12. Device according to one of claims 9 to 1 1, characterized in that the conveyor belt (12) on a discharge side at least one release bar (17) or at least one rotatable take-up roller is assigned, which extends transversely to the conveyor belt (12) ,

13. Device according to one of claims 6 to 12, characterized in that the separating device (18) has a plurality of dissolving rollers (17.1) and / or a plurality of godets (18.2) which in each case upstream of the winding stations (19) are.