Device for manufacturing container products
Patent Information
- Application Number
- DE102023003533
- Authority / Receiving Office
- DE · DE
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-08-29
- Publication Date
- 2025-03-06
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Abstract
Description
[0001] The invention relates to a device for producing container products, in particular using a forming, filling and closing process, at least consisting of - at least one material-providing unit, such as an extruder device, which is stationary at a predeterminable location, and - at least one further material processing unit following this one unit in the manufacturing process, such as an extrusion device.
[0002] DE 10 2020 004 564 A1 discloses a device for producing plastic containers by means of a forming, filling and closing process, comprising at least a forming device with individual forming tools which can be repeatedly moved relative to one another from an open receiving position into a forming closed position, and an extrusion unit by means of which at least one extruded plastic tube can be introduced into the open receiving position of the forming tools, wherein the extrusion unit can be moved in the opposite direction with each extruded plastic tube by means of a displacement device relative to the forming device which is fixedly arranged in each position of the forming tools.With such a continuous extrusion of the plastic hose by means of the extrusion unit, the shaping can be carried out stationary by means of the molding tool, so that the production of the container products is facilitated due to the resulting exact alignment of the mold halves of the molding tool.
[0003] EP 2 909 000 B1 discloses a device for producing container products from plastic materials, in particular by carrying out a forming, filling and sealing process, comprising a forming device to which a formed tube of plasticized plastic material can be fed and which has movable forming surfaces simulating a predeterminable container geometry, against which the formed tube can be placed for a forming, filling and / or sealing process, wherein a guiding and holding device is provided which has movable guiding and holding parts which can be controlled in such a way that in at least one of the possible functional positions outside the forming area of the forming device, these act on the formed tube itself and / or on the respective plastic material which surrounds at least one finished container product and / or its contents, wherein the movable guiding and holding parts are arranged at the end of a respective forming,During the filling and sealing process for the container product, they can be brought into a functional position in which they rest on the molded tube in the section adjacent to the inlet of the molding device, supporting it on opposite sides of the tube. The support thus formed in the immediate vicinity of the head area of the containers ensures particularly reliable demolding with uniform detachment of the containers from the mold surfaces, which move apart during the demolding process.
[0004] Based on this state of the art, the invention is based on the object of being able to better adapt the known solutions to changing production specifications.
[0005] A device having the features of patent claim 1 in its entirety solves this problem.
[0006] Because, according to the characterizing part of patent claim 1, the respective material-processing unit is designed as a mobile unit and as part of a quick-change system, and is interchangeably attached to the respective stationary unit, the device as a whole can be converted in a very short time to accommodate changed production specifications. Such conversion is necessary, for example, if the number of cavities in a mold changes according to the production specifications, which is synonymous with a change in the distance between the cavities, which is also technically referred to as the cavity pitch. Ultimately, such changes serve to produce containers with a different geometry and / or containers with varying fill volumes.While changing the respective molding tool is usually associated with relatively little effort in practice, changing an extrusion head together with a filling and adjustment unit, the actual material-processing unit for manufacturing the container products, is often very complex. Changing the plastic material for the respective container product, for example, from low-density polyethylene (LDPE) to polypropylene (PP) and vice versa, is similarly complex. As stated above, the conversions discussed here typically require at least 8 to 14 hours in the state of the art, which naturally adversely impacts the availability of the system and thus its productivity.
[0007] With the present device according to the invention, which is designed as a quick-change system, a rapid changeover from material-providing units, such as stationary extruder devices, to material-processing units, such as mobile extrusion devices, can be achieved as needed. This allows for a quick changeover between different container formats and / or sizes, in particular with different spacing of the filling tubes (cavity spacing) and / or different numbers of filling tubes (number of cavities) and / or different plastics or polymers – hereinafter also referred to as format changeover – to adapt to changing production specifications in a simple manner.
[0008] Such a format change is not only advantageous to carry out on-site during ongoing production if necessary, but also brings advantages in the context of the initial equipment of such a manufacturing device, in particular in the context of the production of so-called blow molding, filling and closing machines (BFS machines).
[0009] In a preferred embodiment of the device according to the invention, it is provided that the quick-change system has a carrier element on the side of the respective material-processing further unit and has a holding or support element for the carrier element on the side of the respective material-providing unit, and that the two mutually assignable units are connected in a releasable manner by means of a coupling.
[0010] Preferably, the coupling, as part of the quick-change system, comprises at least one centering device acting between the carrier element and the holding or support element (hereinafter also referred to as the support element) and / or at least one coupling, such as a coupling clamp, connecting the extruder device to the extrusion device for material transport. Thus, to carry out the aforementioned format change, only a corresponding format module, here in the form of the mobile extrusion device, needs to be replaced using the aforementioned coupling. After reconnecting individual supply lines for electrical power and compressed air as well as the product lines, usually using the quick-change couplings commonly used in technology, production of the container products can be restarted, with such a format change being implemented in less than two hours.
[0011] The extrusion device, which has been replaced or simply removed from the device, is then available for cleaning and / or maintenance purposes if necessary, preferably without significantly interrupting the use of the production device, by continuing production with a substituted extrusion device. The mobile extrusion device in question can be replaced with the same device or, in the case of a format change, with a modified extrusion device.
[0012] In another particularly preferred embodiment of the device according to the invention, it is provided that the respective mobile unit can be precisely fixed to the associated stationary unit in a predeterminable installation position by means of the centering device. By means of the centering device, the respective mobile unit is positioned essentially or entirely on the associated stationary unit by gravity, so that no new alignment processes are necessary during changeover, which regularly requires the use of complex measuring technology. Once the extrusion device has been fixed in its functional position by means of the centering device, the production process can resume immediately.For safety reasons, depending on local safety regulations, it may also be necessary for the mobile extrusion device to be secured to the stationary extruder device with additional securing means, for example by using an auxiliary screw connection.
[0013] The two units to be coupled together are preferably divided as follows: The respective stationary unit consists of at least - an extruder, - a machine frame, and - a molding device. In contrast, the mobile unit consists of at least - an extrusion head, - the support element with the centering device and / or a holder for a centering device arranged on the machine frame, - a filling device, and - a traversing device.
[0014] In this way, the stationary extruder device is combined with a connectable mobile extrusion device as a complete manufacturing device in the manner of a modular building block system.
[0015] In a preferred embodiment of the device according to the invention, it is provided that the machine frame has at least two longitudinal beams as a support element, which project spatially beyond the extruder device and define a receiving space between them, which receives the extrusion head of the mobile unit in such a way that it is freely accessible from one end face of the machine frame.
[0016] Preferably, it is further provided that the carrier element has a support plate, on the upper side of which at least parts of the displacement and filling device are placed and on the underside of which the extrusion head is arranged, which can be supplied with a filling medium from the filling device via a recess in the support plate.
[0017] Particularly preferably, the support plate has a projection at the edge, viewed in the longitudinal direction of the two adjacent longitudinal beams, by means of which the support plate can be placed onto the longitudinal beams along a horizontal support plane. This allows the mobile unit to be replaced from the front side of the device, which is largely kept free of third-party components, with all essential components of the mobile unit being mounted on an easily replaceable support plate.
[0018] In a further preferred embodiment of the device according to the invention, the support plate has additional openings next to the recess to allow the flow of a gaseous fluid, preferably low-germ and low-particle air. The additional air allows for targeted control of temperature and humidity and, if necessary, for maintaining or creating a clean room climate in the molding and filling areas.
[0019] Furthermore, the invention also relates to a method for carrying out a quick-change process, in particular using a device as specified above, wherein for an exchange process a material-processing, mobile unit can be removed from a material-providing, stationary unit by means of a handling system, such as a lifting truck, and wherein a connection between the two said units can be established with precise positioning by means of a centering device and a plastics-processing production position for receiving container products is assumed essentially or entirely due to gravity, wherein the molten plastic is provided by the material-providing, stationary unit.The handling system, particularly in the form of the lifting truck, can be adapted particularly easily to the desired module exchange for a format change, so that an exchange process is possible with little effort.
[0020] In the following, the solution according to the invention is explained in more detail using an embodiment according to the drawing. The drawings show in principle and not to scale the Fig. 1 a perspective oblique view from the front of the device as a whole; Fig. 2 one of the Fig. 1 corresponding representation of a material-producing unit in the form of an extruder device; Fig. 3 one of the Fig. 1 corresponding representation, but as an exploded drawing, of a material processing device in the form of an extrusion device; Fig. 4 a support element according to the Fig. 3 modified support element; Fig. 5 a partially sectioned connection solution between the extruder and extrusion device by means of a centering device; and Fig. 6 one of the Fig. 1 corresponding representation with a handling device for the material processing facility in the form of a pallet truck.
[0021] The Fig. Figure 1 shows the essential components of a device for manufacturing container products, in particular using a form, fill, and seal (FSS) process. The device comprises, as a key component, a material-providing unit 10, such as an extruder device 12, which is usually stationary at a predeterminable location 14 corresponding to the production site. A further essential component is a material-processing unit 16, usually in the form of an extrusion device 18, following this unit 10 in the manufacturing process. Fig. 1 is characterized according to the invention in that the respective material processing unit 16 is designed as a mobile unit 20 and as part of a quick-change system designated as a whole by 22, and is interchangeably fixed or fixable to the respective stationary unit 10, which will be explained in more detail below.
[0022] For this purpose, the quick-change system 22 has, as shown in the illustration, Fig. 3 on the side of the respective material-processing further unit 16 a carrier element 24 and according to the illustration according to the Fig. 2 on the side of the respective material-providing unit 10 a support element 26 for the carrier element 24. Furthermore, the two mutually assignable units 10, 16 are connected in a detachable manner by means of a coupling designated as a whole by 28, which can be seen in particular from the illustration according to the Fig. 3 results.
[0023] The coupling 28 of the quick-change system 22 has a centering device 30 acting between the carrier element 24 and the support element 26 as well as a coupling in the form of a Fig. 3 shown coupling clamp 32. For this purpose, both the extruder device 12 and the extrusion device 18 have a coupling flange 34, which in Fig. 3 is shown only for the extrusion device 18. The respective coupling flanges 34 correspond to each other and are held together by the coupling clamp 32 in such a way that the plasticized plastic material provided by the extrusion device 18 as the material ordering unit 10 is passed on to the material processing unit 16 in the form of the extrusion device 18 for container production. In this respect, the coupling clamp 32 seals the material connecting point between the devices 10, 16 accordingly. The centering device, designated as a whole by 30, will be described in more detail below, in particular with reference to the Fig. 5, are described in more detail.
[0024] The Fig. The manufacturing device shown in Figure 1 typically has a machine frame 36, consisting of longitudinal and transverse beams 38 and 40, respectively, which are stiffened by cross bars 42. The device as a whole can be erected at the installation or production location 14 via such a machine frame 36, usually in the form of a hall floor. Furthermore, the machine frame 36 has wall sections 44 of a machine housing 46 in a so-called C-frame construction. In this case, the Fig. 1, the lower wall part 44 forms a base part of the machine housing 46 and the upper wall part 44 running parallel thereto is the head part of the machine housing 46. Between the said base and the head part extends a substantially vertically running housing section with the associated middle wall part 44. The Fig. The machine construction shown in Figure 1 only represents the structure in a highly simplified manner and only to the extent that this is necessary for understanding the invention. As will be further apparent from the Fig. 1, the machine frame 36 has, as a support element 26, two uppermost longitudinal beams 48 which accommodate the essential parts of the extruder device 12 between them and, passing through the middle wall part 44 and emerging on the front side of the machine housing 46, form the support element 26 as a whole as a respective support point.
[0025] As can be seen from the Fig. 1, a molding device 50 with its housing 52 is shown below the extrusion device 18 and only partially. Such a molding device 50 can, for example, have individual molded parts running along a production line, which can be moved toward and away from each other in pairs to close or open a manufacturing mold for the production of the container products. Such a molding device is shown as an example in DE 10 2008 006 073 A1.
[0026] In a different type of forming device 50 according to the teaching of DE 10 2020 004 564 A1, at least one vertically oriented plastic tube (not shown) is continuously extruded in the direction of the stationary forming device 50 by means of the extrusion device 18, so that the output of the respective plastic tube from the extrusion device 18 remains essentially uninterrupted throughout the entire manufacturing process. At the beginning of a process cycle, the extrusion device 18, together with each continuously extruded tube, is moved from an upper end position toward the open molds of the forming device 50 over a distance corresponding to the total height of a finished plastic container less the tube length extruded during this travel movement.Unlike what is shown in the figures, this arrangement requires an extrusion device 18 that can be moved up and down vertically, for which the quick-change system 22 discussed here can also be used. Further forming devices are disclosed, for example, in EP 2 909 000 B1 and in the subsequently published DE 10 2023 001 313.7, which further discloses a longitudinally movable extrusion device that can assume multiple positions on the BFS machine and can also be designed to be interchangeable using the quick-change system 22. The above statements demonstrate that, in principle, the units 10, 16, which are detachably connected to one another via a coupling 28, can be used for almost any BFS machine design.
[0027] The respective stationary unit 10 essentially consists of an extruder 54 of the extruder device 12, as well as the machine frame 36 and a suitable forming device 50 as described above. In contrast, the mobile unit 16 essentially consists of at least an extrusion head 56 of the extrusion device 18, the carrier element 24 with the centering device 30, a conventional filling device 58, and a displacement device 60, which are also state-of-the-art for such extrusion devices 18.
[0028] As can be seen from the Fig. 2, the two upper longitudinal beams 48, after passing through the middle wall part 44, protrude forward into the surroundings with the same beam length and have on their upper side, as part of the centering device 30, a circular recess 62 with at least one inclined surface, which is at least partially designed in the manner of a fitting surface 64, which can be seen in more detail in the sectional view according to the Fig. 5. A fitting piece 66, as a further component of the centering device 30, engages from above into the respective, identically held recess 62. The fitting piece 66 has at least one corresponding contact surface 68 on the edge, which comes into contact with the fitting surfaces 64 of the respective recess 62 without a gap such that, viewed in the axial direction of use, the fitting piece 66 opens into the associated longitudinal member 48 at an axial distance 70 above the recess 62. In this way, the fitting piece 66 engages in the associated recess 62 in a self-centering manner. Instead of circular surface pairs 64, 68, other surface fits between the fitting and contact surfaces 64, 68 can also be selected which are self-centering, for example in a polygonal shape.
[0029] The respective circular fitting piece 66 is received in a corresponding recess 72 on the underside of the support element 24, which in the present case essentially consists of a flat support plate 74. As can be seen from the Fig. 5, the respective fitting piece 66 protrudes with a predeterminable axial projection beyond the underside of the support plate 74, so that the pairing of contact surfaces 68 with fitting surfaces 64 ensures precise centering of the support element 24 or the support plate 74 on the horizontally extending upper side of the thus flat longitudinal members 48. Two pairs of screwed-through fastening elements 76 are used to fasten the fitting piece 66 to the support plate 74. These fastening elements are covered by a plug-like cover element 78, the upper side of which is flush with the upper side of the support plate 74. Other fastening options are conceivable here. In particular, the fitting piece 66 can also be fastened to the longitudinal member 48, and the associated recess 62 is then located on the side of the support plate 74.Due to the self-centering by means of the centering device 30, the mobile unit 20 remains on the upper side of the support element 26 due to gravity.
[0030] As can be seen in particular from the Fig. 2, the middle wall part 44 is provided with a through-opening 80 between the two upper longitudinal beams 48, which serves for the passage of the coupling flange 34 of the extrusion head 56 as part of the extrusion device 18, so that in the direction of view of the Fig. 2, the coupling 28 to the extruder 54 is effected via the coupling clamp 32 in the rear region of the central wall section 44 of the machine housing 46. The two uppermost longitudinal beams 48 of the machine frame 36 define a receiving space 82 between them, which accommodates the extrusion head 56 of the mobile unit 20 in such a way that, in the coupled state, the extrusion head 56 is freely accessible from a front end face 84 of the machine frame 36. In this respect, the receiving space 82 as well as the front free end face 84 of the machine frame 36 are delimited at the foot and floor sides by the horizontally extending further wall sections 44 of the machine housing 46.
[0031] As can be seen particularly from the presentation according to the Fig. 1 and Fig. 3, the support plate 74 is part of the carrier element 24, on the upper side of which at least parts of the displacement device 60 and the filling device 58 are placed, and on the underside of which the extrusion head 56 is arranged, which can be supplied with a filling medium from the filling device 58 via a rectangular recess 86 in the support plate 74, through which the filling device 58 partially extends. For the supply of the filling medium, the filling device 58 extends through the recess 86 at its one free, lower end and is connected to the extrusion head 56 and the blowing and / or filling mandrels (not shown for better clarity) which partially extend therein in order to supply material. This arrangement is common in forming, filling and closing machines, so that it will not be discussed in more detail here.
[0032] As can be seen from the presentation after the Fig. 1, the support plate 74 has a projection at the edge in the longitudinal direction of the two adjacent uppermost longitudinal beams 48, by means of which the support plate 74 can be placed along a horizontal mounting plane on the longitudinal beams 48. In this way, all components of the centering device 30 that can be assigned to the support plate 74 are arranged along the respective projection of the support plate 74. As shown in particular in the illustration according to Fig. 4, which relates to a modified embodiment of the support plate 74, this can have one or more longitudinal slots 88, which preferably extend along both sides of the support plate 74 in rows arranged one behind the other, wherein the longitudinal direction of the respective slot opening of a longitudinal slot 88 is parallel to the respective long side of the support plate 74 and transverse to the two transverse sides of the support plate 74 as well as transverse to the rectangular recess 86 in the support plate 74.
[0033] In particular, the longitudinal slots 88 are arranged between the projection of the support plate 74 on the associated longitudinal beam 48 and the recess 86 in the support plate 74. For a good flow of a gaseous fluid, such as nitrogen or air, in particular low-particle and low-germ air, the longitudinal slots 88 are formed continuously in the support plate 74 and open on the underside of the support plate 74 into an intermediate space formed by the adjacently arranged longitudinal beam 48 and an adjacent wall side of the extrusion head 56. Except for the design with the longitudinal slots 88, the embodiment according to the Fig. 4 not from the one as it is in the Fig. 1 to 3 and 5 and 6.
[0034] As in particular the Fig. 5 shows, for lines such as electrical lines, compressed air lines, etc., which lead in particular to the extrusion head 56 in order to connect it to a central supply point (not shown), a plug-based quick coupling system 90 is provided, which allows a rapid separation of the extrusion head 56 from the central supply point and a reconnection, wherein the connected position via the coupling system 90 is shown in the figures.
[0035] The Fig. 6 now shows a possible exchange process for the material-processing, mobile unit 20 using a handling system, here in the form of a lifting truck 92. The lifting truck 92 has a chassis 94 with wheels, by means of which the lifting truck 92 can be moved as a whole. Furthermore, the lifting truck 92 has a lifting fork 96, which is guided by a lifting actuator 98 so that it can be moved up and down between adjacent frame-like cheeks 100 of the lifting truck 92. The lifting fork 96 has two identically designed fork tines 102 on its free end face, which mutually delimit an opening space 104 into which the extrusion head 56 can be received for a transport process.
[0036] After opening the coupling clamp 32 and releasing the quick coupling system 90, the Fig. 6, the lifting fork 96 with its two fork tines 102 can be moved in the direction of the extrusion head 56, for which purpose an upper travel plate 106 can be moved back and forth relative to a base table 108 by means of actuators not shown in detail, i.e. transversely to the up and down movement of the base table 108 together with the travel plate 106 by means of the lifting actuator 98. Instead of using actuators, however, a manual displacement of the travel plate 106 relative to the base table 108 between the cheek frames 100 can also be provided. In any case, the two fork tines 102 engage in the assignable distances between the upper longitudinal beams 48 and the respective longitudinal outer side of the extrusion head 56. Subsequently, by controlling the lifting actuator 98, the base table 108 with the travel plate 106 can be raised so that the support plate 74 lifts off the two adjacent longitudinal beams 48 while simultaneously disengaging the centering device 30.The travel plate 106 is then moved with the mobile unit 20 into its position in the . Fig. 6 and the mobile unit 10 can be moved to a maintenance or replacement location (not shown) using the lifting truck 92. A serviced and / or cleaned mobile unit 20 can then be returned to its place of use as shown in the illustration after the Fig.1, or the lifting carriage 92 allows for replacement with a different type of mobile unit 20 for the purpose of performing the aforementioned format change on a BFS machine. If the mobile unit 20 is replaced immediately, production can continue with the BFS machine shown without significant production downtime. This has no equivalent in the prior art. It is understood that instead of a lifting carriage 92, another handling system can also be used, for example in the form of a handling robot, a forklift, or the like (not shown). QUOTES CONTAINED IN THE DESCRIPTION
[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature
[0000] DE 10 2020 004 564 A1 [0002, 0026] EP 2 909 000 B1 [0003, 0026] DE 10 2008 006 073 A1
[0025] DE 10 2023 001 313.7
[0026]
Claims
[1] Device for producing container products, in particular using a forming, filling and closing process, at least consisting of - at least one material-providing unit (10), such as an extruder device (12), which is arranged stationary at a predeterminable location (14), and - at least one further material-processing unit (16) following this one unit (10) in the manufacturing process, such as an extrusion device (18), characterized by that the respective material processing unit (16) is designed as a mobile unit (20) and as part of a quick-change system (22), and is interchangeably fixed to the respective stationary unit (10). [2] Device according to claim 1, characterized by that the quick change system (22) - has a carrier element (24) on the side of the respective material-processing further unit (16) and - on the side of the respective material-providing unit (16) has a support element (26) for the carrier element (24), and - that the two units (10, 16) which can be assigned to one another are connected in a detachable manner by means of a coupling (28). [3] Device according to claim 1 or 2, characterized by that the coupling (28) of the quick-change system (22) has at least one centering device (30) acting between the carrier element (24) and the support element (26) and / or at least one coupling, such as a coupling clamp (32), connecting the extruder device (12) to the extrusion device (18) for material transport. [4] Device according to one of the preceding claims, characterized by that by means of the centering device (30) in a predeterminable installation position, the respective mobile unit (20) can be fixed in a precise position on the assignable stationary unit (10). [5] Device according to one of the preceding claims, characterized by that by means of the centering device (30) the respective mobile unit (20) is positioned essentially or completely by gravity on the assignable stationary unit (10). [6] Device according to one of the preceding claims, characterized by that the respective stationary unit (10) consists at least of - an extruder (54), - a machine frame (36), and - a forming device (50). [7] Device according to one of the preceding claims, characterized by that the mobile unit (16) consists at least of - an extrusion head (56), - the carrier element (24) with the centering device (30) and / or - a receptacle for a centering device (30) arranged on the machine frame (36), - a filling device (58), and - a traversing device (60). [8] Device according to one of the preceding claims, characterized by that the machine frame (36) has, as a support element (26), at least two longitudinal beams (48) which project spatially beyond the extruder device (12) and define between them a receiving space (82) which receives the extrusion head (56) of the mobile unit (20) in such a way that the latter is freely accessible from an end face (84) of the machine frame (36). [9] Device according to one of the preceding claims, characterized by that the carrier element (24) has a support plate (74), on the upper side of which at least parts of the displacement (60) and filling device (58) are placed and on the underside of which the extrusion head (56) is arranged, which can be supplied with a filling medium from the filling device (58) via a recess (86) in the support plate (74). [10] Device according to one of the preceding claims, characterized bythat the support plate (74) has a projection on the edge side in the longitudinal direction of the two adjacent longitudinal beams (48), by means of which projection the support plate (74) can be placed on the longitudinal beams (48) along a horizontal placement plane. [11] Device according to one of the preceding claims, characterized by that the support plate (74) has additional openings (88) next to the recess (86) to allow a flow of a gaseous fluid such as nitrogen or air, preferably air low in particles and / or germs. [12] Method for carrying out a quick-change operation, in particular using a device according to one of the preceding claims, characterized byin that, for an exchange process, a material-processing, mobile unit (20) can be removed from a material-providing, stationary unit (10) by means of a handling system, such as a lifting truck (92), and in that a connection between the two units (10, 20) can be established with precise positioning by means of a centering device (30), and a plastics-processing production position for receiving container products is assumed essentially or entirely due to gravity, which is provided by the material-providing, stationary unit (10).
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