Strand pelletizer and apparatus for feeding strands of plastic material to such a strand pelletizer

Abstract

This invention relates to an apparatus for supplying plastic filament to a filament pelletizer. The apparatus includes a nozzle plate for producing plastic filament, a preferably downwardly inclined conveying trough positioned below the nozzle plate, and a scraper. The nozzle plate has a plurality of nozzle outlets distributed laterally for discharging the plastic filament. The conveying trough is used to convey the plastic filament from the nozzle plate to the filament pelletizer. The scraper is used to scrape the nozzle plate and / or separate the plastic filament discharged from the nozzle plate. The scraper is capable of continuous movement laterally over the plurality of nozzle outlets and can be set to opposite set angles by an angle adjustment device when making opposite travel movements in the lateral direction.

Description

Technical Field

[0001] This invention generally relates to a wire pelletizing machine. More particularly, it relates to an apparatus for supplying plastic wire to the wire pelletizing machine, the apparatus comprising a nozzle plate for producing the plastic wire, a preferably downwardly inclined conveying trough positioned below the nozzle plate, and an abstreifer. The nozzle plate has a plurality of nozzle outlets arranged laterally for discharging the plastic wire, the conveying trough for conveying the plastic wire from the nozzle plate to the wire pelletizing machine, and the abstreifer for scraping the nozzle plate and / or separating the plastic wire discharged from the nozzle plate. Prior Technology

[0002] In in-line or dry-cut wire pellet mills, plastic wire is typically produced by a continuous casting machine (Stranggießer) comprising a nozzle plate with a series of nozzle outlets. The plastic wire is fed into a conveyor trough, on which it is transported side-by-side from the continuous casting machine to the pellet mill for processing into cylindrical pellets. The conveyor trough may be positioned below the casting machine by its feed-side end or possibly intermediately connected feed table, and sloped downwards away from the casting machine. The conveyor trough may have a liquid cooling device to cool the initially hot, viscous, and possibly sticky plastic wire, solidifying it to a degree suitable for pelletizing in the pellet mill. The application of coolant can also improve transport on the conveyor trough, particularly in the case of sticky plastic wire. The liquid cooling device may work with water or other coolants and may be sprayed or dripped onto the conveyor trough, or the coolant may be allowed to trickle down the conveyor trough. If necessary, the conveying trough can lead directly to the granulator, or it can also lead to a conveyor belt that may be connected in the middle, which then conveys the plastic filaments to the granulator and feeds them to the granulator's cutting blades.

[0003] Here, the nozzle plate of the continuous casting machine is typically equipped with a scraper to clean the nozzle outlet or the outlet surface by scraping away or removing plastic residue deposited on the outlet surface of the nozzle plate around the outlet orifice. Specifically, the plastic wire discharged from the nozzle plate can be separated by this scraper, which is necessary, for example, during the start-up of the granulation process, to discharge plastic wire that is not yet suitable for granulation and to prevent it from reaching the conveyor trough, instead collecting it, for example, on an inserted discharge table or allowing it to fall into a prepared water tank. For example, when starting the process, the wire diameter may still be unstable, or the wire temperature may still fluctuate, or contaminated plastic wire may still be present if the supplied material is changed. The scraper can be used not only during process start-up but also at the end of batch production or when the process is interrupted to separate the plastic wire discharged from the casting machine and clean the nozzle plate on the outlet side.

[0004] In principle, it is not easy to place the scraper in the narrow area between the nozzle plate and the feed trough of the casting machine, or to design the equipment so that the feed trough can be moved away during startup or the feed table can be pushed between them. Therefore, various scraping mechanisms have been proposed.

[0005] To achieve both a compact design and sufficiently fast separation of wire or scraping of the nozzle plate, it is known to use a blade as a scraper. This blade extends through the nozzle plate and is long enough to simultaneously scrape adjacent nozzle outlets arranged in a row. Here, the blade moves parallel to the nozzle plate across its width and cuts the discharged wire more or less simultaneously. In this case, in time with the movement of the blade, the feed table can be moved below the nozzle outlet, or the aforementioned conveying trough can be moved below the nozzle outlet so that the wire is subsequently carried away by water and conveyed to the cutting head.

[0006] Here, the cutter bar can also be positioned slightly inclined relative to the nozzle outlet along the transverse direction of its arrangement, thereby achieving minimal time difference when cutting the wire. However, the time deviation is very small, so the wire enters the cutting head approximately simultaneously, resulting in a sudden increase in resistance at this point. During the scraping process, the cutter bar also tends to "jump" on the nozzle plate surface, thus failing to achieve a truly clean nozzle plate surface. This jumping effect is also related to the rapid scraping motion of the cutter bar, but it is necessary to prevent the melt from contacting the back of the cutter and uncontrollably adhering there. In order to perform this movement accordingly quickly, the cutter is typically guided in the molds on the left and right sides of the continuous casting machine and can be moved back and forth by a pneumatic cylinder. Due to the relatively long length of the cutter bar and its guidance only at the end, the tendency to bounce on the nozzle plate is further exacerbated.

[0007] Another problem is that the tool blade is at least partially adhered to by the melt after the scraping process. Cleaning is relatively difficult due to the narrow area between the foundry and the feed trough. However, if the melt is not removed manually if possible, it solidifies and affects the next scraping process.

[0008] Although the aforementioned method of directly guiding the cutter bars on the left and right sides of the casting machine results in a relatively long span of the cutter bars without support, its advantage is that the adjustment of the guide template is very easy and constant, so the cutter bars can be positioned very precisely at the nozzle plate outlet face.

[0009] On the other hand, it has also been proposed to fasten the scraper to the feed table or conveyor trough, and then a template can be set on the casting machine to guide the movement of the scraper relative to the nozzle plate surface. For example, such scrapers fastened to the feed table or output conveyor trough are shown in documents EP 0 079 609 A1 and US 4,528,157.

[0010] However, a drawback of scrapers that are fixed to the feed table or conveyor trough is their sensitivity to changes in position between the feed table and the foundry. The alignment of the conveyor trough or feed table relative to the foundry has an adverse effect on the scraping results, as even small thermal expansion effects can cause fluctuations in the relative position that affect the scraping outcome.

[0011] To avoid a sudden increase in load on the pelletizer's cutting blades when almost all the plastic filaments being cut are fed to the blades simultaneously during startup, and also to avoid the aforementioned blade bounce problem on the nozzle plate surface, a scraper has been proposed to be guided laterally on the nozzle plate, with the nozzle outlets arranged adjacent to each other in this lateral direction. This ensures that the plastic filaments exiting the nozzle outlets are not all cut simultaneously, but rather cut one after another, or rather, gradually. In this way, the scraper guided laterally on the nozzle plate can have a significantly smaller length or width, which essentially only needs to be slightly larger than the nozzle outlet diameter, or can have a certain margin to scrape the perimeter around the nozzle outlet.

[0012] Such scrapers that can move laterally are known in various design forms. For example, they can be fastened to a drain channel, such as a water tank, which can be pushed under the casting machine along with the tool, so that the wire separated by the scraper can be conveyed to a waste container via the drain channel.

[0013] When the equipment starts, the drainage trough moves to one side, thereby releasing strands of wire onto the feed platform or conveyor trough, allowing the wire to gradually enter the pelletizer's cutting head. This allows the pelletizer to be started with only a small increase in load.

[0014] On the other hand, the distance between the drain channel and the nozzle outlet becomes very narrow, which often leads to clogging, requiring correspondingly complex cleaning. Another problem is that the guides for the drain channel, or the scrapers fastened to them, are located in the area through which rising steam from the melt and evaporated coolant passes. Therefore, the guides are often difficult to move, and the system is prone to clogging, requiring regular maintenance and cleaning. Overall, the cleaning of the nozzle plate in this design still needs improvement to date.

[0015] Laterally movable scrapers are also used in devices including laterally movable feed tables with water tanks. Here, the scraper can be fastened to the feed table with water tank, wherein the feed unit can be attached to a linear guide rail on the machine frame and can be pushed from one side under the foundry. If the unit is moved out from the side of the machine, the wire falls vertically downward into the waste container. At startup, the unit is moved under the foundry, whereby the wire gradually falls onto the feed table and is conveyed by water to the cutting head or conveyor trough.

[0016] Here, the scraper fastened to the feed table can be spring-pressed to compensate for the alignment error between the casting machine and the feed table, thus improving the cleaning quality of the nozzle plate.

[0017] Regardless, this type of feed platform, which extends laterally, is very complex and requires a significant amount of space. Within the casting machine's area, the machine is twice as wide as a conventional machine, or requires twice the installation space. Furthermore, numerous guides are needed, as the water tank must be lifted and moved in addition to the cutting tools. Overall, this not only hinders machine installation and the required installation space but also makes machine transportation difficult. Summary of the Invention

[0018] Based on this, the object of the present invention is to provide an improved wire pelletizer and an improved apparatus for supplying plastic wire to such a wire pelletizer, which avoid the disadvantages of the prior art and further develop the prior art in an advantageous manner. In particular, an efficient and clean scraper should be provided in a compact structure, which is insensitive to the positioning tolerances of the feed trough and enables the equipment to start up stably without load jumps on the pelletizer.

[0019] Therefore, it is proposed that instead of moving the scraper simultaneously on all nozzle outlets of the nozzle plate, the scraper be guided continuously in a transverse direction on the nozzle outlets, and the scraper is set to be inclined at an acute angle to the nozzle plate outlet surface according to the direction of movement. According to the invention, the scraper can be guided continuously on multiple nozzle outlets along the transverse direction in which the nozzle outlets are arranged adjacent to each other, and when making opposite travel movements in the transverse direction, the scraper can be set to opposite set angles by means of an angle adjustment device. If the scraper moves from left to right on the nozzle plate, its inclination is different from its inclination when moving from right to left on the nozzle plate.

[0020] By scraping the nozzle plate laterally, not only is the impact or impact load on the scraper reduced, thus decreasing its tendency to jump on the nozzle plate, but the plastic wire is also gradually cut and fed into the conveyor trough. This ensures that during startup, not all the plastic wire reaches or is supplied to the cutting blades of the wire pelletizer simultaneously, but rather gradually, thus avoiding load jumps on the wire pelletizer. This allows the wire pelletizer to start gently with only a slight increase in power.

[0021] At the same time, because the scraper's tilt position or positioning relative to the nozzle plate is adapted to the direction of travel, a very good cleaning effect is achieved.

[0022] Specifically, as the scraper moves on the nozzle plate, it can be positioned at an angle to the nozzle plate, much like a handheld scraper. The leading edge of the scraper can be set at an acute angle to the nozzle plate, while the trailing edge can be set at an obtuse angle. This allows the scraper or scraper to be pulled tightly onto the nozzle plate without any tendency to jump, even under higher contact pressures.

[0023] Here, the scraper can be designed in the form of a blade or a plate scraper and / or a substantially flat strip, but the scraper can also have a slight curvature, such as a tapered shape that tapers towards the joint edge. Regardless of this, the scraper can have a substantially constant cross-section or constant profile over its width, for example, in the form of an extruded profile, but the scraper can also be designed as a simple scraper plate, which can be sharp or blunt at the joint edge. In the latter case, two joint edges can be provided, which become effective depending on the direction of movement and the set angle.

[0024] The scraper may have a straight engagement or working edge, which may also abut linearly against the nozzle plate surface when the scraper is positioned at an acute angle. The scraper may be arranged perpendicular to the direction of movement using the engagement or working edge, i.e., a preferred plate scraper is not guided on the nozzle plate in the manner of an inclined snowplow, but rather runs on the nozzle plate in a front-oriented manner (although the acute angle setting angle is present on the leading edge of the scraper).

[0025] Advantageously, the scraper can be movably guided on the casting machine by a scraper guide, or the scraper guide can be fastened to the continuous casting machine. Therefore, the scraper can be precisely guided relative to the nozzle plate surface, and the scraper is insensitive to the positioning tolerances of the feed trough or any possible feed table or drain trough, which can be completely omitted to save space.

[0026] In particular, the scraper guide can be directly fastened to the continuous casting machine, for example, to a casting head having the nozzle plate on the exit side.

[0027] Regardless of this, the scraper guide may have a carriage guide or guide profile, along which the scraper can move in the lateral direction. The carriage guide or guide profile may advantageously be arranged on the casting machine side away from the nozzle plate or its outlet side, or on a side different from the nozzle plate side or its outlet side. Specifically, one or more guide profiles may be arranged behind the bottom wall and / or on the casting machine side away from the falling direction of the plastic wire and / or upward-facing, such that plastic vapor or coolant mist or rising vapor emitted from the discharged wire does not reach the guide profile. Therefore, contamination of the scraper guide can be avoided, and long-term blockage-free operation can be ensured even without frequent maintenance intervals.

[0028] At least one or more guide profiles may extend parallel to the nozzle outlet in a transverse direction of their arrangement, such that the scraper may move parallel to said transverse direction.

[0029] Here, the scraper guide may have a carriage capable of moving laterally in the aforementioned manner, and the scraper may be rotatably or pivotally mounted on the carriage to allow for changing or altering the set angles for forward and backward travel. To move the carriage, a lateral drive, for example including an electric motor, may be provided; a controllable motor such as a stepper motor may be used.

[0030] In an advantageous improved example of the invention, the angle adjustment device for changing the set angle of the scraper may have a rotary drive having a rotation drive axis perpendicular to the direction of travel and / or parallel to the nozzle plate exit surface, so as to be able to adjust the set angle of the scraper relative to the nozzle plate in a desired manner, or to be able to change the set angle for forward and backward travel.

[0031] Preferably, the rotary drive can provide an adjustable preload, drive power, or adjustable torque to adjust the contact force of the scraper relative to the nozzle plate. For example, a rotary motor can be used to rotate the scraper back and forth according to the direction of its movement on the nozzle plate. If the scraper is against the nozzle plate, the contact force can be adjusted by changing the torque of the rotary motor.

[0032] However, in principle, it is also conceivable to connect the scraper to a spring-pretensioned rotary drive, or to install a spring stage in the transmission system between the rotary motor and the scraper, so that the scraper can essentially self-adjust its set angle as it moves on the nozzle plate, and set to an acute angle by deflecting the spring stage. This can compensate for any slight unevenness or shape tolerance of the travel path relative to the plate surface. If necessary, the set angle can also be changed by moving the scraper outside the nozzle plate, allowing the spring mechanism to jump or move to a neutral position, and by reversing the direction of movement and subsequently impacting the nozzle plate.

[0033] For example, the angle adjustment device may include a swivel cylinder (Schwenkzylinder), which may have a rotation axis parallel to the nozzle plate surface and perpendicular to the lateral direction of the scraper's movement. Here, the scraper can be directly mounted on the swivel cylinder, such that the rotational movement of the swivel cylinder causes a change in the scraper's set angle.

[0034] The swing cylinder or the aforementioned rotary drive can be fastened to the carriage, which can move back and forth in the lateral direction by means of the aforementioned scraper guide.

[0035] To move the scraper or carriage back and forth, a carriage driver or shift driver can be advantageously provided, which moves the scraper in the lateral direction on the nozzle plate by means of a scraper guide. Such a shift driver can advantageously include a controllable drive motor, for example, in the form of a stepper motor. This controllable motor can be specifically used or configured to scrape the scraper at an end position on a potentially heated plate or cleaning scraper blade to remove contaminants from the plastic filament on the scraper.

[0036] The carriage can be arranged on the side of the casting machine opposite to the nozzle plate outlet surface, particularly positioned on the side facing upwards and / or away from the conveyor trough. A cantilever support arm, extending on the nozzle plate outlet surface and holding the scraper in the nozzle outlet area, can be fastened to the carriage. The cantilever support arm can be formed by a rotary actuator, such as the swing cylinder, by means of which the set angle of the scraper relative to the nozzle plate can be adjusted and repositioned according to the direction of movement. Simple Explanation of the Diagram

[0037] The present invention will now be described in more detail with reference to preferred exemplary embodiments and related figures.

[0038] [Figure 1] shows an overall perspective view of a wire granulation apparatus according to an advantageous embodiment of the invention, which includes a wire granulator with dry or wet cutting, a continuous casting machine, and a means for supplying plastic wire produced by the continuous casting machine to the wire granulator.

[0039] [Figure 2] shows a perspective view of the nozzle plate of the continuous casting machine in the wire rod granulation equipment of Figure 1, wherein the scraper assigned to the nozzle plate is shown at the end position on one side of the nozzle plate.

[0040] [Figure 3] shows a perspective view of the nozzle plate and associated scraper of the continuous casting machine in the starting position before the scraping process.

[0041] [Figure 4] shows a perspective view of the scraper during the scraping stroke, viewed from the production direction or from the perspective of Figure 4 (from left to right).

[0042] [Figure 5] shows a partial side view of the nozzle plate on which the scraper acts, showing the set angle of the scraper relative to the nozzle plate. Implementation

[0043] As shown in Figure 1, the granulation equipment 1 may include a continuous casting machine 2 for producing hot, viscous plastic wire 3, which is supplied by the continuous casting machine 2 to a conveying trough 4. The conveying trough 4 is arranged below the continuous casting machine 2 via a supply-side end that may be formed by an extendable or movable supply table or feed table 5, and can be inclined out from the continuous casting machine 2 so that the supplied plastic wire can be transported side by side on the conveying trough 4. However, instead of such a movable feed table, the entire conveying trough 4, or at least its end near the casting machine, can be rotated during startup, particularly swinging upwards, so that when the equipment starts, the plastic wire 3 does not fall onto the conveying trough 4, but falls into a prepared scrap pan. Such a rotatable conveying trough can be particularly advantageous if the conveying trough 4 has a fairly steep operating position (which can be steeper than that shown in Figure 1), because by rotating the conveying trough about a (particularly horizontal) axis of rotation arranged, for example, at the downstream end of the conveying trough, the conveying trough can be very easily removed from the unloading area of ​​the casting machine 2.

[0044] Here, the conveying trough 4 can lead to the wire pelletizer 6, for example, directly into the supply area of ​​the wire pelletizer 6, so as to supply the plastic wire 3 to the cutting device of the wire pelletizer 6. This cutting device (not specifically shown) may, for example, include a roller-shaped cutting rotor with protruding strip-shaped cutting bars, which can interact with fixed, reverse-direction cutters. However, an intermediate conveyor can also be provided between the inclined conveying trough 4 and the wire pelletizer 6, which takes over the plastic wire from the downstream end of the conveying trough 4 and transports it into the wire pelletizer 6.

[0045] The conveying tank 4 may have a liquid cooling device 7 that applies coolant to the conveying tank 4 and / or the plastic filament conveyed thereon to cool and solidify the plastic filament to a degree suitable for granulation. The liquid cooling device 7 may include, for example, nozzles above and / or on the sides of the conveying tank 4 to spray the cooling liquid onto the conveying tank dropwise or in a spray manner. Alternatively or supplementarily, the coolant may also be supplied to the entire surface of the conveying tank 4 in a trickle manner.

[0046] Here, the conveying trough 4 can be equipped with a conveying element in the form of a conveyor belt or conveyor roller, but it can also have a sliding bed, where the wire can slide along the sliding bed at least by means of a coolant.

[0047] The continuous casting machine 2 includes a nozzle plate 8, the outlet side of which faces downward in the intended operating position and / or towards the conveying trough 4 or the feed or feed table 5, so that the plastic wire 3 discharged from the nozzle plate 8 can reach the conveying trough 4 downward under the action of gravity.

[0048] Here, the nozzle plate 8 includes at least one row of nozzle outlets 9, which may be designed, for example, to pass through through holes in the nozzle plate 8. The cross-section of such nozzle holes need not be constant when observing the hole length; rather, depending on the desired material and wire characteristics, it may be tapered or widened on the outlet side in the manner of a stemmed glass. However, cylindrical nozzle holes as nozzle outlets 9 can also typically be provided.

[0049] As shown in Figures 2 to 4, the nozzle outlets 9 are distributed along a transverse direction 10, which extends transversely to the conveying direction of the conveying trough 4. The transverse direction 10 can extend horizontally and be oriented perpendicular to the conveying direction 11 of the conveying trough 4 (see Figures 1 and 2).

[0050] Here, the nozzle plate 8 may have an outlet side 12 or outlet surface with a substantially flat design, and the nozzle outlet 9 opens on the outlet side 12 or outlet surface. The outlet side 12 faces downward toward the conveying trough 4 or the feed table 5 and may be oriented horizontally or nearly horizontally, but may also be arranged at an angle similar to that shown in Figure 2, for example, with an inclination of 0-45° to the horizontal plane or possibly even steeper.

[0051] The nozzle plate 8 has a scraper 13 that can move on the outlet side 12 of the nozzle plate 8 in the area of ​​the nozzle outlet 9 in order to clean the nozzle outlet 9 and / or separate the plastic thread 3 discharged therefrom.

[0052] The scraper 13 may be designed as a plate-shaped scraper blade or form a plate-shaped scraper (see Figures 2-4), wherein the scraper 3 may advantageously have at least a nearly straight working edge 14 that can abut against the flat exit surface of the nozzle plate 8.

[0053] As shown in Figures 2 to 4, the scraper 13 can move relative to the nozzle plate 8 in the transverse direction 10 so as to gradually sweep across the nozzle outlet 9 and gradually separate strands of plastic material.

[0054] Advantageously, the scraper 13 is mounted on the continuous casting machine 2 by means of a scraper guide 15, particularly directly fastened to the continuous casting machine 2, wherein the scraper guide 15 provides the scraper 13 with a translational motion axis parallel to the transverse direction 10. In addition to the translational motion axis 16, a rotational motion axis 17 may also be provided for the scraper 13, which may extend perpendicular to the translational motion axis 16 and / or parallel to the outlet side 12 of the nozzle plate 8.

[0055] Advantageously, the scraper guide 15 may include a carriage 18 on which the scraper 13 is rotatably or pivotally mounted about the rotational motion axis 17, wherein the carriage 18 itself is movable relative to the nozzle plate 8 along the translational motion axis 16.

[0056] For example, the carriage 18 can be slidably mounted on one or more guide profiles 19, such as guide rails, which can extend parallel to the transverse direction 10 and be fastened to the continuous casting machine 2.

[0057] As shown in the figure, the guide profile 19 is advantageously arranged on the continuous casting machine side different from the outlet side 12 of the nozzle plate 8, particularly on the side facing upwards and / or away from the conveying trough 4 of the continuous casting machine 2. In particular, the carriage 18 and the guide profile 19 can be isolated from the supply area of ​​the nozzle plate 8 and / or the conveying trough 4 by means of a bottom wall or top wall, so that the steam or water vapor mixture generated from the plastic wire 3 cannot rise to the guide profile 19.

[0058] As shown in Figure 2, the carriage 18 or guide profile 19 can be located on the adjacent side of the casting machine 2, which is adjacent to the outlet side of the nozzle plate 8, but facing a different direction, especially upward.

[0059] A cantilever support arm 20 may be provided on the carriage 18. The support arm 20 may protrude beyond the nozzle plate 8 and extend from the carriage 18 beyond the nozzle plate 8 to the area of ​​the nozzle outlet 9, so as to support the scraper 13 therein.

[0060] The support arm 20 or at least a portion thereof may be formed by a rotary actuator 21, which may include, for example, an elongated oscillating cylinder that can protrude from the carriage 18 beyond the nozzle plate 8.

[0061] Here, the rotary drive 21 can be part of the angle adjustment device 22, by which the set angle α of the scraper 13 relative to the nozzle plate 8 can be adjusted (see Figure 5).

[0062] The rotary drive 21 can form the aforementioned rotary motion axis 17 of the scraper guide 15, wherein the rotary motion axis 17 can extend from the outlet side 12 of the nozzle plate 8 parallel to the outlet side, and in particular perpendicular to the lateral direction 10.

[0063] If the rotary drive 21 is, for example, an electric motor, then the axis of the motor shaft can define the axis of rotational motion 17.

[0064] As shown in Figures 2 to 4, the angle adjustment device 22 can be configured to set the scraper 13 at an acute angle to the outlet side 12 of the nozzle plate 8, specifically such that when the scraper 13 moves, the leading edge of the scraper is inclined at an acute angle to the outlet side of the nozzle plate 8, while the trailing edge of the scraper is inclined at an obtuse angle to the outlet side of the nozzle plate 8.

[0065] Advantageously, the leading edge of the scraper can be tilted relative to the nozzle plate 8 at an angle α (see Figure 5), which is approximately 15° to 85°, or 25° to 75°, or 35° to 75°, wherein other setting angles α may also be advantageous depending on the plastic to be processed. Here, the angle adjustment device 22 may include an automatic adjustment mode by means of which the setting angle is automatically adjusted. However, if necessary, a manual input mode may also be available by means of which the setting angle can be variably determined. In order to achieve full contact with the nozzle plate 8 at different set angles, the scraper 13 can be fixed to the rotary drive 21 in a variable position (e.g., in a continuously movable manner) so that the scraper 13 is moved more or less toward the nozzle plate 8 depending on the selected setting angle.

[0066] However, it may also be sufficient to use a scraper 13 held in a fixed position on the rotary drive 21, wherein the scraper 13 can achieve a tight fit on the nozzle plate 8 by rotating about a rotation axis. Specifically, the rotary drive 21 may also be designed or controlled such that it does not approach a predetermined set angle, but rather presses the scraper 13 against the nozzle plate 8 with sufficient force, or rotates in such a way that it brings the scraper 13 into contact with the nozzle plate 8. For example, a desired driving force or a desired driving torque can be set for this purpose, which ensures that the scraper 13 has a desired contact force (Anstellkraft) on the nozzle plate 8.

[0067] In order to enable the scraper 13 to clean the nozzle plate 8 in both directions of travel from right to left and from left to right, the angle adjustment device 22 is designed to adjust the set angle differently or in opposite directions of travel, and preferably such that the corresponding leading edge forms an acute angle with the nozzle plate 8, while the trailing edge forms an obtuse angle with the nozzle plate 8.

[0068] In order to enable the scraper 13 to rotate back and forth between different set angles, the scraper guide 15 provides sufficient mobility so that the scraper 13 can move beyond and disengage from the nozzle plate 8. Therefore, the scraper 13 can rotate back and forth between a right-end position and a left-end position that are laterally spaced from the nozzle plate 8.

[0069] In order to remove dirt from the scraper 13, a scraper 23 can be provided on at least one side of the nozzle plate 8. The scraper 23 can be advantageously designed to have a sharp edge, such as a blade, along which the scraper 13 can scrape, in particular by the interaction of a translational displacement driver and a rotational drive 21 (see Figures 2 to 4, which show the scraper 23 on the left and right sides of the nozzle plate 8).

[0070] The scraper 23 can be advantageously designed to be heated so that plastic contaminants on the scraper 13 can be removed more easily.

[0071] As shown in Figures 3 and 4, the scraper 13 can initially be positioned on one side of the nozzle plate 8, for example, on the left side according to Figure 3. Here, the scraper 13 has been rotated by the rotary drive 21 to its desired rotational position relative to the axis of rotational motion 17, so as to have a desired set angle relative to the nozzle plate 8 during the subsequent scraping process.

[0072] If it is necessary to clean the nozzle plate 8 or to separate the wire material discharged from the nozzle plate 8, the scraper 13 is moved in the lateral direction 10 on the nozzle outlet 9 by means of the lateral drive 24, so that the scraper 13 gradually separates the discharged wire material and scrapes and cleans the nozzle outlet 9 in turn.

[0073] When the scraper 13 reaches its opposite end position (in the case of the diagram, the right end position), in which the scraper 13 has moved beyond the nozzle plate 8, the rotary driver 21 can rotate the scraper 13 so that it again has the desired set angle when it moves from right to left the next time.

[0074] 1: Granulation equipment 2: Continuous casting machine 3: Plastic Threads 4: Conveying trough 5: Feeding platform 6: Wire pellet mill 7: Liquid cooling device 8: Nozzle plate 9: Nozzle outlet 10: Horizontal direction 11: Conveying direction 12: Export side 13: Scraper 14: Work Edge 15: Scraper guide 16: Translation axis 17: Rotation axis of motion 18: Carriage 19: Guide Profile 20: Support arm 21: Rotary drive 22: Angle adjustment device 23: Scraper 24: Lateral Driver 25: Opposite movement 26: Carriage guide 27: Belt-type

Claims

1. An apparatus for supplying plastic filament (3) to a filament pelletizer (6), the apparatus comprising a nozzle plate (8) for producing the plastic filament (3), a preferably downwardly inclined conveying trough (4) capable of being positioned below the nozzle plate (8), and a scraper (13), the nozzle plate (8) having a plurality of nozzle outlets (9) for discharging the plastic filament (3) distributed in a transverse direction (10), the conveying trough (4) for conveying the plastic filament (3) from the nozzle plate (8). The material is fed to the wire pelletizer (6), and the scraper (13) is used to scrape the nozzle plate (8) and / or separate the plastic wire (3) discharged from the nozzle plate (8). The scraper (13) is characterized in that it is capable of continuous movement along the transverse direction (10) on a plurality of nozzle outlets (9), and when making opposite travel movements (25) along the transverse direction (10), the scraper (13) can be set to opposite set angle (α) by means of the angle adjustment device (22).

2. The apparatus according to claim 1, wherein, The angle adjustment device (22) is designed to provide an acute angle setting angle (α) relative to the nozzle plate (8) at the leading edge of the scraper (13) and an obtuse angle relative to the nozzle plate (8) at the trailing edge of the scraper (13).

3. The apparatus according to claim 2, wherein, The set angle (α) of the leading edge of the scraper (13) toward the nozzle plate (8) is between 15° and 85° or between 25° and 75°.

4. The apparatus according to any one of claims 1 to 3, wherein, The scraper (13) has a straight working edge (14) that abuts against the outlet side (12) of the nozzle plate (8) and is oriented perpendicular to the lateral direction (10).

5. The apparatus according to any one of claims 1 to 3, wherein, The working width of the scraper (13) is greater than the diameter of the plastic wire (3), but less than 50%, 25% or 10% of the extension range of the nozzle plate (8) in the transverse direction (10).

6. The apparatus according to any one of claims 1 to 3, wherein, The angle adjustment device (22) has a rotational driver (21) for rotating the scraper (13) about a rotational motion axis (17) that extends perpendicular to the lateral direction (10) and / or parallel to the outlet side (12) of the nozzle plate (8), wherein the rotational driver (21) is designed to variably adjust the contact force of the scraper (13) relative to the nozzle plate (8) so as to be adjustable in terms of torque and / or its driving force.

7. The apparatus according to claim 6, wherein, The rotary drive (21) has an electric motor.

8. The apparatus according to claim 6, wherein, The rotary actuator (21) has a pressure fluid actuator, particularly a pneumatic cylinder.

9. The apparatus according to any one of claims 1 to 3, wherein, The scraper (13) is fastened to the continuous casting machine (2) to which the nozzle plate (8) belongs by means of the scraper guide (15).

10. The apparatus according to claim 9, wherein, The scraper guide (15) has a carriage guide (26) for carrying the carriage (18) of the scraper (13), the carriage guide / the carriage being arranged on the continuous casting machine side of the continuous casting machine (2) different from the outlet side (12) of the nozzle plate (8).

11. The apparatus according to claim 10, wherein, The carriage guide (26) and / or the carriage (18) are arranged on the casting machine side away from and / or facing upwards from the conveying trough (4).

12. The apparatus according to claim 10, wherein, The angle adjustment device (22) is fastened to the carriage (18) of the scraper guide (15) and extends from the carriage (18) beyond the outlet side (12) of the nozzle plate (8).

13. The apparatus according to any one of claims 1 to 3, wherein, The scraper (13) is capable of moving beyond the nozzle plate (8) on at least one side of the nozzle plate (8) and is capable of rotating between its opposite set angles by means of the angle adjustment device (22) in positions adjacent to the end and / or rotation of the nozzle plate (8).

14. The apparatus according to any one of claims 1 to 3, wherein, The transverse driver (24) for moving the scraper (13) along the transverse direction (10) has a controllable drive motor, which is preferably in the form of a stepper motor.

15. The apparatus according to claim 14, wherein, The transverse drive (24) has a belt stage (27) arranged on the side opposite to the outlet side (12) of the nozzle plate (8), particularly on the casting machine side facing upward.

16. The apparatus according to any one of claims 1 to 3, wherein, The scraper (23) for cleaning the scraper (13) is disposed on at least one side of the nozzle plate (8).

17. The apparatus according to claim 16, wherein, The scraper (23) is fixed, and the scraper (13) is capable of scraping on the scraper (23) by controlled movement of the transverse drive (24) and / or the rotation drive (21) of the angle adjustment device (22).

18. A wire pelletizing apparatus comprising a wire pelletizer (6) for pelletizing plastic wire (3) into pellets and means for supplying the plastic wire (3) to the wire pelletizer (6) according to any one of the preceding claims.

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