EP0245390B1 - Spinning system - Google Patents

Abstract

A spinning system for the production of monofilament yarn comprises a spinning tool (40) and a channel section (4') for a polymer melt (2). The channel section (4') expands widthwise into a channel portion (41, 42) of the spinning tool (40) and opens into a flow channel (43) with the shape of a flattened U and connected to a group of nozzles (59). The area of the cross section (44; 44'; 44'') of the flow channel (43) is thus increased normal to its width at least in the upper part of the channel section (4') for the polymer and the flow channel (43) is kept free from incrustations.

Description

The invention is based on a spinning system for the production of monofilament threads, in which a spinning tool has a polymer channel section for a polymer melt, the width of which widens in a channel part of the spinning tool into a flow channel designed as a flat bracket channel, which is followed by a nozzle block. Such a spinning tool is known from DE-PS 33 34 870.

Such spinning systems are used to spin high quality threads from polymer melts, which due to their use, e.g. B. for filter cloth, tension belts, fishing lines and. Like., Must have constant material properties in a narrow tolerance range. The production of a high-pressure, fine-mesh filter fabric requires threads with a constant diameter on the one hand and, on the other hand, high tensile strength.

In the known spinning system, as described in the patent mentioned at the outset, a dust bar is provided for the uniform exit quantity of a polymer melt along a flat channel, the different distance from a wall of the flat channel regulating the amount of passage of the polymer melt. The dust bar must therefore be flexible in itself or consist of several individual elements so that its length can form a different distance from the wall. The polymer melt is dammed up in the flat channel by the dust bar, and according to its set distance, a certain amount of polymer melt can pass through a set gap per unit of time.

Due to the high product and housing temperatures that occur during the production of monofilament threads, the dust bar must be sealed particularly carefully. This is particularly complex at temperatures of around 300 ° C. In addition, sealing elements of moving machine parts are known to be more prone to failure at elevated temperatures. If different material expansions occur, the distance of the dust bar / wall must be readjusted during operation. This requires a complex monitoring unit for the gap between the wall and the dust bar.

The invention is therefore based on the object of developing the spinning system of the type mentioned in such a way that the polymer melt is distributed steadily and uniformly in the entire free space of the flat bar channel in the case of laminar flow and without stall, so that the nozzle block has a constant polymer mass flow over its entire width at the greatest Production security is fed.

This object is achieved in that a cross-sectional area of the flow channel perpendicular to its width increases at least in the upper region from the polymer channel section and that the flow channel is free of internals.

The spinning system according to the invention therefore has the essential advantage that the shape of the flow channel distributes the polymer mass flow evenly over the entire flow channel. The three-dimensional spatial contour of the flow channel is designed as a function of the viscosity and the flow curve of a raw material to be processed so that the polymer melt has a constant flow velocity over the entire outlet cross section of the flow channel.

The flow channel also has the advantage that it is free of internals and thus has no leading edges which could disrupt or change the flow profile of the polymer melt in the flow channel. This constructive solution guarantees a maximum of operational safety and ease of maintenance, since the flow channel does not contain any adjustable installation parts and the resulting sealing problems can be excluded.

It is also possible to develop the three-dimensional spatial contour of the flow channel for different materials with different viscosities and flow curves. However, if polymer melts with very different product properties are processed in the spinning tool, the flow channel must be replaced in accordance with the product properties of the raw material.

In a further embodiment of the invention, the cross-sectional area tapers in the direction of the nozzle block and opens into an opening which has a constant width over the entire width.

This embodiment of the flow channel ensures that rectangular plates with linearly arranged bores or nozzle openings can be easily coupled to the outlet cross section of the flow channel. The width of the tapered opening results from the performance of the spinning tool.

Furthermore, the flow channel is preferably formed by joining together a first and a second channel part, a three-dimensional spatial contour of the flow channel being formed on at least one of the inner sides of the channel parts.

The fact that the river channel consists of a two-shell construction enables a very simple and exact production of the three-dimensional spatial contour of the river channel. For example, the spatial contour for certain product properties can be calculated numerically, and a numerically controlled machine tool then mills the calculated spatial contour into at least one of the duct parts designed as metal blocks. In addition, with a double-shell construction, it is possible to further process or close the surfaces of the river channel chrome-plated so that particularly smooth surfaces are created. If the polymer melt is allowed to solidify in the spinning tool, then when the channel parts are dismantled, a solidified polymer body can be removed which reflects the perfect shape of the channel flowed through. This enables the distribution of the polymer melt to be checked particularly simply when a plurality of melts are processed with a single flow channel space shape.

In a further development of the invention, the nozzle block is part of a nozzle package which has a lower nozzle insert part which receives the nozzle block, a perforated plate, a sieve and an upper nozzle insert part.

The element-like structure of the nozzle package enables individual replacement of the individual components. Nozzle blocks with different nozzle shapes can be used. Depending on the arrangement of the nozzles, a perforated plate matched to the nozzle block distributes the polymer melt and feeds it to the individual nozzles. Depending on the polymer melt, sieves of different pore sizes based on metal fleece are arranged above the perforated plate and filter out dirt particles from the polymer melt. The holes in the upper part of the nozzle insert pre-distribute the polymer melt in the nozzle package. The interaction of the individual components in the nozzle package results in a further homogenization of the polymer flow with a simultaneous increase in the nozzle service life and spinning reliability during production.

In one embodiment of the invention, the spinning tool is enclosed on two sides by clamping plates, which enclose the nozzle block on a third side perpendicular to the two sides and press against the channel part.

This enables the duct part to be connected to the nozzle block in a simple manner. The clamping plates and the lower part of the nozzle insert ensure on the broad side of the nozzle block that the losses of heat radiation in the region of the nozzle block are as small as possible. Temperature gradients are therefore negligibly small across the entire width of the nozzle block.

In a further embodiment of the invention, the clamping plates for guiding the nozzle packet have jaws at their ends comprising the nozzle packet perpendicular to the plane of the screen. In a special embodiment, the jaws are designed as dovetail connections that interact with the lower part of the nozzle insert.

The duct parts, which can be heated and regulated via known devices, are protected by the clamping plates covering them, and their heat radiation is inhibited. The type of connection between the lower part of the nozzle insert and the jaws of the clamping plates creates a line pressure between the nozzle block and the adjacent parts, which, in contrast to punctiform pressing with through screws, presses the nozzle block evenly against the duct parts. The heat transfer from the heated duct parts to the nozzle block and to the parts surrounding them is therefore particularly good. Furthermore, the nozzle block is guided particularly safely and evenly by the type of connection.

In a preferred embodiment of the invention, the clamping plates for releasing the nozzle block can be displaced vertically from the channel parts to the channel parts, and the jaws open laterally beyond the clamping plates into guide rails in which the nozzle block can be guided to outside the spinning tool.

This has the advantage that the nozzle block can be replaced quickly. This avoids longer downtimes of a spinning system and increases the efficiency of a production system.

In a preferred embodiment of the invention, the channel part is detachably connected to a carrier which is fastened to a vertically displaceable holder which runs in a fixed and horizontal rail.

The spinning tool can thus be adjusted in height in the vertical direction and horizontally displaced with respect to a fixed point in space via a rail. This opens up the possibility of easily adjusting the heavy spinning tool compared to connectable systems.

In a further embodiment of the invention, the end faces of the carrier have clamping devices which engage in the clamping plates.

An eccentric clamp connection has proven to be particularly expedient, by means of which the clamping plates can be displaced in the vertical direction.

The use of eccentrics has the advantage that when the new nozzle package is re-clamped, its connection is self-locking, so that the nozzle block does not become detached from the channel parts even if the switching elements actuating the eccentric fail.

In a further embodiment of the invention, the spinning tool is constructed so that two or more nozzle blocks, flow channels and polymer channel sections are contained in the spinning tool.

The use of a second nozzle package enables the use of different nozzle shapes in one spinning tool. In this way, monofilament threads of different quality requirements can be produced at the same time with a single Soinn tool.

In a preferred embodiment of the invention, a dosing unit with its output can be coupled to the spinning tool on the input side and conveys the polymer melt into the spinning tool.

The spinning tool is adjusted to the position of the dosing unit. This enables a quick and exact connection of the two systems. The spinning tool or the dosing unit can be exchanged as a complete unit. The distribution or delivery characteristics of a polymer melt can be changed easily.

The dosing unit consists in a preferred version staltung of the invention from a divisible housing block that receives a spinning pump flowing through in the flow direction of the polymer melt, wherein a static mixer can be integrated into the outlet of the spinning pump.

The spinning pump with the static mixer is used in the polymer flow direction in recesses in the housing block so that the separable housing parts ensure the exact positioning of the spinning pump. A quick, simple replacement of the spinning pump with the static mixer is also possible when the spinning system is hot, since the polymer melt is conveyed in the spinning pump in the direction of mass flow and no additional fastening screws between the housing block and the spinning pump are necessary.

The spinning pump picks up the polymer melt without deflection within the pump and conveys it in precisely metered quantities through the integrated static mixer to the flow channel of the spinning tool. The static mixer compensates for even the smallest temperature fluctuations in the polymer melt due to its high mixing capacity and ensures that the polymer melt flows into the flow channel of the spinning tool at a uniform temperature.

The divisible housing block can be heated and regulated by known means, such as, for. B. via a controlled resistance heater. This has the advantage that the spinning pump with the integrated static mixer has a uniform temperature.

In one embodiment of the invention, the spinning pump with the static mixer can be used as a self-contained unit in the housing block.

This has the advantage that the two functional parts do not have to be matched to one another in the spinning system. This particularly facilitates the installation of this spinning pump under difficult conditions, i. H. e.g. B. in the hot state of the spinning system or in confined spaces.

In a further embodiment of the invention, a spinning pump with a continuously adjustable spinning pump drive supplies the respective polymer channel sections of the spinning tool with the polymer melt. With this measure, a fluctuation range in the delivery accuracy of individual spinning pumps can be compensated for, and a uniform, constant mass flow of the polymer melt is guaranteed in all polymer channel sections.

If, in a preferred embodiment of the invention, the metering unit is arranged fixed in space, this has the advantage that when the spinning system is at a standstill, the spinning tool can be quickly and easily separated from the metering unit via its horizontal 1 'sliding options. This ensures short inspection and changeover times on the spinning system.

In a further preferred embodiment of the invention, the metering unit forms the connection of the polymer channel section between the inlet of the spinning tool and an outlet of a polymer distributor.

The polymer distributor consists of a first distributor piece and a second distributor piece, which are interchangeable, through which the polymer stream can be split into several side channels.

This has the advantage that the polymer melt is precisely metered and intensively mixed again before it enters the spinning tool.

By splitting the polymer channel into several side channels, the polymer melt can flow into several separate metering units, which in turn convey the polymer melt in different amounts into different flow channels of a spinning tool or into different spinning tools with different flow channels. The throughput performance of a spinning system can be reduced or increased simply by changing the distributor pieces and the nozzle packs or their individual components. If the production of monofilament threads increases, additional spinning systems can be connected to two existing spinning systems.

In a further embodiment of the invention, the inlet of the polymer distributor is connected to an outlet of a central melt filter, and the melt filter is provided with sieve packs which can be replaced during operation, as is known per se.

The use of a melt filter in front of the polymer distributor, the dosing unit and the spinning tool significantly increases the production reliability of a spinning system. Soiling of the polymer melt is largely retained in the melt filter, and the strainer in the nozzle package is largely relieved, so that the service life of a nozzle package is increased significantly. The metal fleece-based sieve in the nozzle package can be selected with a more fine pore filtering of the polymer melt and thereby improves the quality of the polymer melt, which is spun into monofilament threads. By replacing dirty sieve packs during operation, the utilization of such a spinning system is increased considerably.

In a preferred embodiment of the invention, the melt filter in a sieve housing has a piston which can be displaced at an angle to the polymer channel and which is provided with a first sieve recess and a second sieve recess which are equipped with the sieve packets.

This embodiment enables the piston to be displaced without disturbing the mass flow of the polymer melt in the spinning system.

Furthermore, the melt filter preferably has inlet channels in the sieve housing, which are closed in a first and third position of the piston and in a second position of the piston connect the polymer channel continuously to the sieve cutouts on the inlet side.

In the first and third positions of the piston there is one of the two screen cutouts always completely in the mass flow of the polymer melt, while the other sieve saving lies outside the melt flow. As a result, a sieve saving can always be cleaned and a sieve packet can be exchanged without interrupting the mass flow in the spinning system.

_'' In a further embodiment of the invention, in the second position of the piston, one of the two sieve recesses is continuously connected to the polymer channel on the inlet and outlet side, the other sieve recess has a continuous connection to the polymer channel only on the inlet side, this sieve recess additionally having inlet and outlet sides Vent channels in the housing is connected continuously.

This has the advantage that every screen cutout is completely filled with polymer melt before it is led through a piston displacement into the polymer stream. A flooding of the sieve saving located outside of the melt flow ensures that changing the sieve packet during operation does not reduce the quality of the production of the monofilament threads.

In a further development of the invention, the piston can be moved into a position that connects one of the two sieve recesses on the inlet and outlet side to the polymer channel, the other of the two sieve recesses has only one inlet-side passage to the polymer channel and is only connected to the outlet-side ventilation channel.

This has the advantage that the respective screen cutout and its screen pack can be vented step by step during the flooding. While in the second position of the piston the part of the screen cutout on the inlet side is preferably vented and through which polymer melt flows, in the position of the piston described the polymer melt flows through the entire screen cutout. The relevant screen cutout and the polymer melt are completely vented and are free of gas inclusions. In a further embodiment of the invention, the spinning tool, the metering unit, the polymer distributor and the melt filter are designed as individual components and can be detached from one another. This enables existing systems to be modernized easily, since individual components can be integrated into them independently of one another.

Further advantages result from the description and the attached drawing.

• Fig. 1 eine seitliche Prinzipdarstellung, teilweise aufgebrochen, eines Ausführungsbeispiels eines erfindungsgemäßen Spinnsystems ;
• Fig. 2a bis 2c verschiedene Arbeitspositionen eines Schmelzefilters des Spinnsystems gemäß Fig. 1 ;
• Fig. 3a, 3b Ausführungsbeispiele eines Polymerverteilers in einer Draufsicht im Schnitt 111-111 gemäß Fig. 1 ;
• Fig. 4 ein Spinnwerkzeug in einer Schnittdarstellung IV-IV, in vergrößertem Maßstab, gemäß Fig. 1 ;
• Fig. 5a bis 5c ein Flußkanalprofil gemäß den Positionen Va-Va, Vb-Vb, Vc-Vc in Fig. 4 ;
• Fig. 6 eine Schnittdarstellung des Düsenpakets, im vergrößerten Maßstab, gemäß Fig. 1 ;
• Fig.7a eine Vorderansicht eines geschlossenen Spinnwerkzeugs mit einem neuen Düsenpaket in einer Führungsschiene ;
• Fig. 7b eine Vorderansicht eines geöffneten Spinnwerkzeugs mit einem verschmutzten Düsenpaket in einer Führungsschiene ;

The invention is illustrated in the drawing and is explained in more detail with reference to exemplary embodiments in the drawing. Show it :

• Fig. 1 is a schematic side view, partially broken away, of an embodiment of a spinning system according to the invention;
• 2a to 2c different working positions of a melt filter of the spinning system according to FIG. 1;
• 3a, 3b embodiments of a polymer distributor in a plan view in section 111-111 of FIG. 1;
• 4 shows a spinning tool in a sectional view IV-IV, on an enlarged scale, according to FIG. 1;
• 5a to 5c a flow channel profile according to the positions Va-Va, Vb-Vb, Vc-Vc in Fig. 4;
• FIG. 6 is a sectional view of the nozzle package, on an enlarged scale, according to FIG. 1;
• 7a shows a front view of a closed spinning tool with a new nozzle package in a guide rail;
• 7b shows a front view of an opened spinning tool with a soiled nozzle pack in a guide rail;

1 shows a spinning system 1 through which a polymer melt 2 flows. A connecting pipe 3 with a polymer channel 4 connects the spinning system 1 on the input side to a dynamic mixer (not shown) and an extruder, which feed the liquid polymer melt 2 to the spinning system 1.

A melt filter 5 is coupled to the connecting pipe 3 and consists of a housing 6 and a piston 7 which is displaceable in the housing 6. The piston 7 contains screen cutouts 8 which are equipped with screen packs 10.

The polymer melt 2 flows through the melt filter 5, which filters out contaminants in the polymer melt 2. By moving the piston 7, a dirty sieve packet 10 can be replaced when the spinning system 1 is in operation. When changing the sieve packet 10, the mass flow of the polymer melt 2 is not interrupted. 2a to 2c, various operating states of the melt filter 5 are still explained.

The polymer melt 2 flows from the melt filter 5 into a polymer distributor 20, which is detachably connected to the melt filter 5 via a first flange connection 21. The polymer distributor 20 divides the polymer channel 4 into side channels 24, only one of which is shown in FIG. 1. The polymer melt 2 can be homogeneously and evenly distributed over the side channels 24. 3a and 3b, two exemplary embodiments of the polymer distributor 20 are explained by way of example.

The polymer melt 2 flows from the side channels 24 into metering units 30, of which FIG. 1 shows only one, each of which is connected on the output side to second flange connections 26 of the side channels 24 of the polymer distributor 20. The metering units 30 receive in their divisible housing blocks 31 a spinning pump 32 which is equipped with a continuously variable spinning pump drive 33. A static mixer 34 can be integrated into the outlet of the spinning pump 32. The metering units 30 are set up in a spatially fixed manner via fastening brackets 35. The polymer melt 2 flows in each individual metering unit 30 into the static mixer 34 in precisely metered amounts without deflection. The static mixer 34 is equal to inhomogeneities and temperature rature gradients in the polymer melt 2.

The spinning system 1 is designed such that a temperature 36 and a pressure 37 of the polymer melt 2 are measured on the input side of the metering unit 30. This makes it possible to keep the pressure 37 of the polymer melt 2 constant immediately upstream of the spinning pump 32, regardless of the degree of contamination of the sieve packs 10 in the melt filter 5 or any further pressure losses. The pressure 37 of the polymer melt 2 is checked at the spinning pump inlet and a signal feedback to upstream devices, such as. B. to the extruder, is processed as a control variable so that the pressure 37 of the polymer melt 2 at the spinning pump inlet is constant. A comparable control device is provided for the temperature 36 of the polymer melt 2 at this point in the spinning system 1.

The spinning pump 32 with the integrated mixer 34 is inserted into the divisible housing block 31 of the metering unit 30 in the preheated state. No additional fixation or adjustment is necessary for the operation of the spinning pump 32. Thus, the spinning pump 32 for e.g. B. Maintenance purposes can be replaced quickly and easily.

The polymer melt 2 flows from the metering unit 30 into a polymer channel section 4 'of a spinning tool 40 connected to the metering unit 30. The spinning tool 40 contains a first channel part 41 with one or more polymer channel sections 4'. The polymer channel section 4 ′ widens in the first channel part 41 and / or in a second channel part 42 into a flow channel 43. The second channel part 42 can be separated from the first channel part 41. In their mutual contact surfaces, the flow channel 43 is formed as a flat bracket channel. The flow channel 43 distributes the polymer melt 2 evenly over its width. The flow channel 43 is designed along its width with a changing spatial contour. This is explained further below in relation to FIG. 4 by way of example for the first channel part 41 according to section IV-IV of FIG. 1, just as FIGS. 5a to 5c still show exemplary embodiments of how cross-sectional areas 44, 44 ', 44 "can be formed , which result from the joining of the two channel parts 41, 42.

The polymer melt 2 in FIG. 1 flows homogeneously and evenly distributed over the entire width of the flow channel 43 to an opening 45 at the lower end of the flow channel 43, which has a constant width over its entire width.

A nozzle packet 50 is pressed onto the opening 45 via a first and a second clamping plate 52, 53. The clamping plates 52, 53 include the channel parts 41, 42 on their broad side and are slidably in contact on these sides. The clamping plates 52, 53 are formed at the ends comprising the nozzle packet 50 as jaws 54, 55 which grip the nozzle packet 50 perpendicularly to the sides of the clamping plates 52, 53 and press it against the channel parts 41, 42.

In the nozzle package 50, the polymer melt 2 is divided evenly into threads, which then leave the spinning tool 40 and are fed to downstream devices. 6, the distribution of the polymer melt 2 is explained in more detail with reference to a sectional illustration of the nozzle package 50.

The spinning tool 40 is detachably connected in FIG. 1 via a carrier 65 to a vertically adjustable holder 75 which is horizontally displaceable in a rail 76 held in a fixed position.

2a to 2c, the melt filter 5 is shown in different operating positions. The melt filter 5 consists of the sieve housing 6, the piston 7, 7 ', 7 ", the first sieve recess 8, a second sieve recess 9, the sieve packs 10, 11, receiving channels 12, 12' and ventilation ducts 13, 13 on the inlet and outlet side ', 14, 14'.

The polymer melt 2 flows according to an operating position of the melt filter 5 in FIG. 2a through an opening of the screen housing 6. The screen housing 6 is heated in a controllable manner, so that the piston 7, the screen recesses 8, 9 and the screen packs 10, 11 have the same temperature as the polymer melt 2 have. A temperature 15, 16, 17 of the polymer melt 2 is measured in the mass flow, when it enters the melt filter 5, in the melt filter 5 and when it exits the melt filter 5. These temperature measuring points serve to heat the screen housing 6 as a controlled variable. The opening of the screen housing 6 on the inlet side of the polymer melt 2 widens on the inside towards the piston 7 and merges into the receiving channels 12, 12 '. The receiving channels 12, 12 'are closed in the operating position of the piston 7 by its surface, and the polymer melt 2 can only flow through a breakthrough in the piston 7 into the sieve recess 8 with the exchangeable sieve packet 10. The polymer melt 2 is cleaned of dirt particles as it flows through the sieve packet 10.

If a critical degree of contamination of the screen pack 10 is displayed on the melt filter 5 via a pressure indicator 18 with limit contact, the piston 7 is moved into the operating position piston 7 'according to FIG. 5b, and the polymer melt 2 only flows partially through the screen recess 8 with the screen pack 10. The mass flow of the polymer melt 2 is not interrupted. In the operating position of the piston 7 ', the receiving channel 12 and a segment of the sieve recess 9 overlap. The polymer melt 2 thus flows simultaneously into the first and second sieve recesses 8, 9. Via the inlet-side ventilation duct 13 in the sieve housing 6, which separates the sieve recess 9 in the Position of the piston 7 'connects to the outside of the melt filter 5, the polymer melt 2 can emerge from the melt filter 5, the sieve recess 9 is partially vented. Subsequently, the piston 7 'moves into a position in which the piston surface closes the ventilation channel 13 on the inlet side, but the ventilation channel 14 on the outlet side, with the same recess 9 connects. The polymer melt 2 flows with an uninterrupted mass flow in the sieve recess 8 now also through the entire sieve packet 11 of the sieve recess 9 and completely vented the sieve recess 9. If the screen recess 9 is filled with the polymer melt 2, it flows through the outlet-side ventilation channel 14 from the melt filter 5.

The piston 7 'then moves into the operating position of the piston 7 "according to FIG. 2c, and the switching process from the dirty sieve packet 10 to a new, uncontaminated sieve packet 11 is completed. The dirty sieve packet 10 can be pressed out of the sieve recess 8 for cleaning. Is that Sieve pack 10 cleaned and preheated, it can be reinserted into the sieve recess 8.

If necessary, a new screen pack change can now be carried out in the opposite direction. The screen recess 8 is filled via the inlet channel 12 ', via the inlet-side ventilation channel 13' and then via the outlet-side ventilation channel 14 ', before the melt filter 5 returns to the operating position piston 7 according to FIG. 2a.

3a and 3b, two embodiments of the polymer distributor 20 are shown as an example in section 111-111 according to FIG. 1.

In FIG. 3a, the polymer distributor 20 is composed of a first distributor piece 22 with the polymer channel 4 and a second distributor piece 23 with the side channels 24, 25. The polymer melt 2 is divided into two partial flows, which flow in the side channels 24, 25. The partial flows are fed to one or two separate spinning tools 40 via two metering units 30. If the partial flows of the side channels 24, 25 are fed to a spinning tool 40, this spinning tool 40 is equipped with two polymer channel sections 4 'and two separate flow channels 43 which supply two separate nozzle packs 50, 50'.

3b shows a polymer distributor 20 which is equipped with the first distributor piece 22 and a second distributor piece 23 '. In the distributor piece 23 ', the polymer melt 2 from the polymer channel 4 of the distributor piece 22 is split into four partial streams which flow in the side channels 24', 24 ", 25 ', 25". These partial flows are fed to the spinning tools 40 via four metering units 30. The partial streams can be processed in two so-called “double spinning tools” or in four spinning tools 40.

The polymer distributor 20 consists of a divisible housing which can be heated in a controllable manner. The distributor pieces 22, 23, 23 'which can be inserted into the polymer distributor 20 can consist of polymer channels 4 and side channels 24, 24', 24 ", 25, 25 ', 25" of different diameters. This may be necessary if the spinning system 1 is to be operated with different powers.

4 shows the section IV-IV according to FIG. 1 of the spinning tool 40. The polymer channel section 4 'in the channel part 41 opens at 90 ° into the flow channel 43, which has the shape of a flat bracket channel. The closed three-dimensional spatial contour of the flow channel 43 results from the joining together of the channel parts 41, 42. The shape of the flow channel 43 is calculated from the flow curve of the polymer melt 2 to be processed and from its product properties. The three-dimensional spatial contour is numerically determined with the objective that in the flow channel 43 the polymer melt 2 is distributed uniformly over the width of the flow channel 43 at a constant flow rate and flows into the opening 45 of the flow channel 43 at a constant flow rate. For polymer melts 2 with different flow and product properties, different spatial geometries of the flow channels 43 result if the distribution of the different polymer melts 2 is uniform in the flow channels 43 and the polymer melts 2 are to flow out of the flow channels 43 at a constant flow rate. The spatial geometry of a flow channel 43 can be matched to polymer melts 2 such that a plurality of polymer melts 2 with similar flow and product properties can be evenly distributed in a single flow channel 43. However, if the processing of very different polymer melts 2 is concerned, the channel parts 41, 42 must be replaced with the flow channel 43.

5a to 5c, the different spatial geometry of the flow channel 43 is shown in the section of the channel parts 41, 42 depending on its width according to the positions 5a to 5c shown in FIG. 4. The cross-sectional areas 44, 44 ', 44 "open into an opening 45 with a constant width. It is also possible that the three-dimensional spatial contour of the flow channel 43 is formed only in one of the channel parts 41, 42 and the other half of the channel parts 41, 42 Completes the room contour with a smooth, flat surface.

In FIG. 6 the nozzle packet 50 according to FIG. 1 is shown enlarged in section. It is laterally delimited by the clamping plates 52, 53 and the jaws 54, 55, which engage in a leading edge of the lower part 60 of the nozzle insert. The nozzle package 50 is composed of the lower nozzle insert part 60, the nozzle block 59, the perforated plate 58, the sieve 57 and the upper nozzle insert part 56, which adjoins the undersides of the channel parts 41, 42 in the spinning tool 40. Through the jaws 54, 55, the nozzle packet 50 is guided linearly along its width on both sides. The connection between the jaws 54, 55 and the nozzle insert lower part 60 can be designed differently, such as, for. B. as a dovetail connection. A line pressure is created between the nozzle packet 50 and the undersides of the channel parts 41, 42.

The nozzle block 59 is designed as a rectangular nozzle, in which the nozzle openings are arranged on one or more parallel lines. If there are several lines, the nozzles are more appropriate point to gap. The polymer melt 2 is fed to the die block 59 via the perforated plate 58. The holes in the perforated plate 58 distribute the polymer melt 2 evenly over the rectangular nozzle. Over the holes of the perforated plate 58, the narrow-pored sieve 57 is made of z. B. metal fleece. From the polymer melt 2, 57 dirt particles are filtered with this sieve. Together with the pre-filtering of the polymer melt 2 in the melt filter 5, a high-quality product is achieved which has particularly good properties when spinning to monofilament threads. By pre-filtering the polymer melt 2, the service life of the nozzle package 50 is significantly increased, since the sieve 57 only filters very fine contaminants from the polymer melt 2. The polymer melt 2 enters the nozzle pack 50 via bores in the upper part 56 of the nozzle insert.

7a and 7b show front views of the closed and open spinning tool 40.

7a shows the front view of the spinning tool 40 in the closed state of the first clamping plate 52 on the front and the second clamping plate 53, not shown, on the rear of the spinning tool 40. The nozzle pack 50 is attached to the clamping plates 52 by means of the eccentric clamping connection shown as an example , 53 pressed against the undersides of the channel parts 41, 42. The opposing tension levers 70, 70 'and a pneumatic cylinder 71 are also shown as examples of switching elements for the vertical displacement. A nozzle pack 50 'is inserted into the guide rail 72 and, if necessary, can be inserted into the spinning tool 40 with an open clamping plate 52, 53 via an insertion device 74 in exchange for a defective or soiled nozzle pack 50.

7b shows the open spinning tool 40. The clamping levers 70, 70 'are moved in opposite directions via the extendable pneumatic cylinder 71. Eccentrics 66, 66 'on the front and eccentrics 67, 67', not shown, on the rear of the spinning tool 40 rotate and the clamping plates 52, 53 move downward. There is a free space between the channel parts 41, 42 and the nozzle package 50, 50 '. With the insertion device 74, the nozzle pack 50 ′ provided in FIG. 7 a can be pushed into the spinning tool 40 in the guide rail 72. At the same time, the nozzle pack 50 is pressed out of the spinning tool 40 into the guide rail 73. If the pneumatic cylinder 71 is now closed again, the spinning tool 40 with the newly inserted nozzle pack 50 'is ready for operation.

Claims (31)

1. Spinning system for the production of monofilament yarn, in which a spinning tool (40) comprises a channel section (4') for a polymer melt (2), said channel section (4') expanding widthwise in a channel portion (41, 42) of the spinning tool (40) into a flow channel (43) in the form of a flattened U and connected to a group of nozzles (59), characterized in that a cross-sectional area (44 ; 44' ; 44") of the flow channel (43) is increased normal to the width of the latter at least in the upper part of the channel section (4'), and wherein the flow channel (43) is kept free from incrus- tations.

2. Spinning system as defined in claim 1, characterized in that the cross-sectional area (44 ; 44' ; 44") tapers toward the group of nozzles (59) and leads into an opening (45), said opening (45) being of constant width over its entire breadth.

3. Spinning system as defined in claim 1 or 2, characterized in that the flow channel (43) is formed by the joining-together of a first and a second channel portion (41, 42), a three-dimensional contour of the flow channel (43) being formed on at least one of the insides of the channel portions (41, 42).

4. Spinning system as defined in anyone of claims 1 to 3, characterized in that the group of nozzles (59) is part of a pack of nozzles (50, 50'), said pack of nozzles (50, 50') comprising a nozzle-insert lower part (60), said nozzle-insert lower part (60) accommodating the group of nozzles (59), a perforated plate (58), a strainer (57) and a nozzle-insert upper part (56).

5. Spinning system as defined in anyone of claims 1 to 4, characterized in that the spinning tool (40) is enclosed widthwise on two sides by clamping plates (52, 53), said clamping plate (52, 53) embracing the group of nozzles (59) on a third side normal to the two sides and pressing said group of nozzles (59) against the channel portion (41,42).

6. Spinning system as defined in claim 5, characterized in that at their ends embracing the pack of nozzles (50, 50'), the clamping plates (52, 53) for the guiding of the pack of nozzles (50, 50') comprise jaws (54, 55) normal to the plane of the strainer (57).

7. Spinning system as defined in claim 6, characterized in that the jaws (54, 55) are in the form of dovetail connections, said dovetail connections cooperating with the nozzle-insert lower part (60).

8. Spinning system as defined in anyone of claims 5 to 7, characterized in that the clamping plates (52, 53) are displaceable for releasing the group of nozzles (59) from the channel portion (41,42).

9. Spinning system as defined in anyone of claims 6 to 8, characterized in that the clamping plates (52, 53) are vertically displaceable.

10. Spinning system as defined in anyone of claims 5 to 9, characterized in that the jaws (54, 55) extend laterally beyond the clamping plates (52, 53) in the direction of the third side and join into guide rails (72, 73) the group of nozzles (59) being guidable in said guide rails (72, 73) as far as outside the spinning tool (40).

11. Spinning system as defined in anyone of claims 1 to 10, characterized in that, the channel portion (41, 42) is separably connected to a carrier (65), said carrier (65) being attached to a vertically displaceable mount (75), said mount (75) running in a spatially fixed and horizontal rail (76).

12. Spinning system as defined in claim 11, characterized in that end faces of the carrier (65) comprise clamping devices, said clamping devices engaging the clamping plates (52, 53).

13. Spinning system as defined in claim 12, characterized in that the clamping devices on the carrier (65) are eccentrics (66, 66', 67, 67'), said eccentrics (66, 66', 67, 67') engaging holes (68, 68', 69, 69') in the clamping plates (52, 53).

14. Spinning system as defined in claim 13, characterized in that the clamping plates (52, 53) are displaceable in a vertical direction through the intermediary of the eccentrics (66, 66', 67, 67').

15. Spinning system as defined in anyone of claims 13 or 14, characterized in that the eccentrics (66, 66', 67, 67') are operated by switching elements.

16. Spinning system as defined in claim 15, characterized in that, the switching elements of the eccentrics (66, 66', 67, 67') are composed of a mechanical actuator, particularly a pneumatic cylinder (71), hydraulic cylinder or similar and clamping levers (70, 71') moving in opposite directions.

17. Spinning system as defined in anyone of claims 1 to 16, characterized in that two or more groupes of nozzles (59), flow channels (43) and channel section (4') are contained in the spinning tool (40).

18. Spinning system as defined in anyone of claims 1 to 17, characterized in that a metering unit (30) is connectable with its outlet to the inlet side of the spinning tool (40), said metering unit (30) delivering the polymer melt (2) into the spinning tool (40).

19. Spinning system as defined in claim 18, characterized in that the metering unit (30) consists of a divisible housing block (31), said housing block (31) accommodating a spinning pump (32), said spinning pump (32) being subject to a throughflow in the flow direction of the polymer melt (2), a static mixer (34) being adapted to be integrated into the outlet of spinning pump (32).

20. Spinning system as defined in claim 19, characterized in that the spinning pump (32) with the static mixer (34) is adapted to be inserted as a self-contained unit into the housing block (31).

21. Spinning system as defined in claim 17 and in anyone of claims 19 or 20, characterized in that the respective channel section (4') of the spinning tool (40) are each supplied with the polymer melt (2) by a spinning pump (32) with an infinitely variable spinning pump drive (33).

22. Spinning system as defined in anyone of claims 18 or 21, characterized in that the metering unit (30) is spatially fixed.

23. Spinning system as defined in anyone of claims 18 to 22, characterized in that the metering unit (30) forms the connection of the channel section (4') between the inlet of the spinning tool (40) and an outlet of a polymer distributor (20).

24. Spinning system as defined in claim 23, characterized in that the polymer distributor (20) consists in a first distributor piece (22) and of a second distributor piece (23, 23'), said distributor pieces being replaceable, a polymer channel (4) being able to be split into several side channels (24, 25 ; 24', 24", 25', 25") by said distributor pieces.

25. Spinning system as defined in claim 23 or 24, characterized in that the inlet of the polymer distributor (20) is connected to an outlet of the central melt filter (5).

26. Spinning system as defined in claim 25, characterized in that the melt filter (5) is provided with packs of strainers (10, 11), said packs of strainers (10, 11) being replaceable during operation.

27. Spinning system as defined in claim 25 or 26, characterized in that the melt filter (5) in a strainer housing (6) comprises a piston (7 ; 7' ; 7"), said piston (7 ; 7'; 7") being displaceable at an angle to the polymer channel (4) and being provided with the first strainer recess (8) and a second strainer recess (9), said strainer recesses (8, 9) being equipped with packs of strainers (10, 11

28. Spinning system as defined in claims 27, characterized in that the melt filter (5) in the strainer housing (6) comprises preflooding channels (12, 12'), said preflooding channels (12, 12'), with the piston (7, 7") in a first and a third position, being sealed and, with the piston (7') in a second position, connecting the inlet side of the polymer channel (4) through to the strainer recesses (8, 9).

29. Spinning system as defined in claim 28, characterized in that with the piston (7') in the second position, one of the two strainer recesses (8, 9) has a through-connection on the inlet and outlet sides to the polymer channel (4), the other strainer recess (8, 9) having a through-connection to the polymer channel (4) only on the inlet side, said strainer recess (8, 9) additionally having through-connections to inlet- and outlet-side ventilation channels (13, 14; 13', 14') in the strainer housing (6).

30. Spinning system as defined in claim 28 or 29, characterized in that the piston (7 ; 7', 7") is displaceable into a position providing one of the two strainer recesses (8, 9) with a through-connection on the inlet and outlet sides to the polymer channel (4), the other of the two strainer recesses (8, 9) having a through-connection to the polymer channel (4) only on the inlet side and being connected only to an outlet-side ventilation channel (14 ; 14').

31. Spinning system as defined in anyone of claims 1 to 30, characterized in that the spinning tool (40), and/or a metering unit (30), and/or a polymer distributor (20), and/or a melt filter (5) are in the form of separate modules and are separable from one another.

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