Apparatus and method for forming a tube head by compressing a preform and connecting the tube head to a tube body in order to produce a packaging tube

Abstract

The invention relates to an apparatus and method for forming a tube head by compressing a preform (4) and connecting the tube head to a tube body (5) in order to produce a packaging tube, comprising a multi-part shaping tool (1) that forms a first processing station, in particular having a male die (3) and a multi-part female die (2) in which, in an open state, a preform (4) and a tube body (5) can be introduced and which, during a transition into a closed state, shapes the tube head from the preform (4) and produces the connection to the tube body (5), wherein: the shaping tool comprises cooling devices (6), by means of which parts of the shaping tool (1) can be cooled; the shaping tool (1) also comprises an external shoulder part (7) which, in the closed state, is arranged preferably radially outside and adjacent to an axial end portion (23) of the tube body (5); the external shoulder part (7) comprises a heating device (9, 12, 13) which is arranged and designed such that the axial end portion (23) of the tube body (5) is heated when nearing the external shoulder part (7) and / or when contact is made with the external shoulder part (7).

Description

[0001] Device and method for forming a tube head by pressing a preform and connecting the tube head to a tube body to produce a packaging tube

[0002] There are various procedures for producing packaging tubes. Often, a tube body is produced first and then connected to a tube head, whereby the tube head forms an outlet opening and / or comprises a closure or has means for attaching a closure. The tube bodies are usually cylindrical or almost cylindrical tube pieces or hollow bodies, which in turn can be manufactured in various ways. On the one hand, it is common to produce the tube bodies from a sheet-shaped material, for example a laminate, which is formed into a tube shape with adjacent or overlapping longitudinal edges and connected, for example welded, in the longitudinal direction along the longitudinal edges. After the sheet-shaped material has been formed and welded, the individual tube bodies are usually separated.

[0003] Alternatively, extrusion processes and injection molding processes are also known for producing tube bodies, which may be connected to a tube head in a suitable manner.

[0004] For connecting the tube head to a tube body, approaches are already known in the prior art in which the formation of the tube head by pressing a preform in a corresponding forming tool and the connection of the tube head to the tube body take place essentially simultaneously or at least in a temporally overlapping manner. Compression molding processes, for example, are used for this purpose. In this process, the tube body is placed along a longitudinal direction onto an inner part of a multi-part forming tool. The inner part of the forming tool is also known as a male part, mandrel, or mandrel and can also be designed in several parts.

[0005] A preform, for example made of heated / warmed plastic, is then applied to this inner part of the forming tool, preferably in a ring or donut shape, before the multi-part forming tool is closed from the outside by additional tool parts or is closed. Forming tools are also known that are "upside down" compared to the above embodiment. In this case, the preform is inserted into the outer part of the forming tool, and the inner part is inserted from above. The orientation of the forming tool is irrelevant to the effectiveness of the present invention.By means of a corresponding cavity in the interior of the forming tool in the closed state, into which an axial end section of the tube body also projects in the closed state of the forming tool, the preform is formed or formed into the tube head, in particular pressed, and simultaneously connected to the axial end section of the tube body when closing and during the closed state of the forming tool.

[0006] In order to achieve the fastest and most reliable curing of the formed or pressed tube head and the best possible connection between the formed or pressed tube head and the tube body, the prior art has so far cooled the multi-part forming tool by means of conformal cooling devices, for example both in the area of ​​the inner part, i.e. the male part, the mandrel or mandrel, as well as in the outer parts of the forming tool, for example the multi-part die of the forming tool for forming the shoulder area of ​​the tube head, the neck area of ​​the tube head and the end section of the tube head with preferably conformal cooling devices, in order to be able to initially form the heated or heated applied and accordingly deformable preform, preferably made of molten polymer material or a polymer melt, well and at the same time to achieve solidification and a stable connection as quickly as possible,in particular to produce welding with the tube body.,

[0007] However, due to the actively cooled forming tools of the state of the art and the correspondingly high cooling rate of the preform after it comes into contact with the forming tool, this procedure requires correspondingly high initial temperatures or starting temperatures on the side of the heated preform.

[0008] These high initial temperatures cause several disadvantages. On the one hand, the entire process becomes correspondingly energy-intensive because the preform must be heated to a higher initial or starting temperature, and at the same time, a correspondingly high amount of energy is required to cool the multi-part forming tool.

[0009] Furthermore, the high initial temperatures have the disadvantage that, for example, due to unavoidable temperature fluctuations during the heating process of the preform material, e.g., in an extruder, critical material temperatures can be exceeded. This can lead to undesirable degradation, i.e., premature aging, in the preform material, e.g., in the polymer or polymer melt. This, in turn, can lead to undesirable and negative chemical, optical, and / or mechanical material properties being achieved or remaining after the preform material has cooled and solidified. Furthermore, high initial temperatures have the disadvantage that the time required for the cooling of the tube head material until the demolding temperature is reached, at which the tube head has achieved sufficient strength, is long, which disadvantageously increases the cycle time of the forming tool.

[0010] Another method for producing a tube is disclosed in DE 20 23 652 A1, in which a tube body is inductively heated. However, this requires the tube body to include a metal layer. Heat is thus applied in a very targeted and precise manner to the tube components to be welded. This method requires special tube bodies with a metal layer that can be heated inductively, so its applications are limited.

[0011] Furthermore, AT 249 358 B discloses a method and a device for attaching a tube head to a tubular tube body made of thermoplastic by welding. The connection point is air-cooled by means of an air flow in a separate processing station following the formation of the weld seam, which is formed at / in a previous processing station of the device. A disadvantage of this is that a tube head and a tube body must be manufactured in upstream production steps and at upstream processing stations and must be fed to the device as subcomponents—in particular as a finished tube head.

[0012] US Pat. No. 5,690,764 A discloses a method for producing a tube by ultrasonic welding. The disadvantage of this method is that it also requires prefabricated tube heads and tube bodies. Against this background, the object of the present invention is to propose a device and a method that overcome the disadvantages of the prior art and, in particular, enable a more energy-efficient and reliable compression of the preform, including the formation of the connection to the tube body.

[0013] This object is achieved with a device for forming a tube head by compressing a preform and connecting the tube head to a tube body to produce a packaging tube, having the features of claim 1. With regard to a method for forming a tube head by compressing a preform and connecting the tube head to a tube body to produce a packaging tube, the above-mentioned object is achieved with the features of claim 10.

[0014] Advantageous embodiments are the subject of the following description, the description of the figures, the figures and the dependent claims.

[0015] In order to avoid or minimize unnecessary repetition, all features disclosed in terms of the device shall be deemed to be correspondingly disclosed and claimable in terms of the method, and vice versa.

[0016] The device for forming a tube head by pressing a preform and connecting the tube head to a tube body to produce a packaging tube comprises a multi-part forming tool forming a first processing station, in particular comprising a male mold, and a multi-part die, into which a preform and a tube body can be introduced in an open state and which, upon transition to a closed state, forms the tube head from the preform, in particular presses it, and establishes the connection to the tube body, wherein the forming tool has cooling devices with which parts of the forming tool can be cooled, wherein the forming tool, in particular the die, comprises an outer, preferably itself multi-part, shoulder part, which in the closed state is arranged, preferably radially outward, adjacent to an axial end portion of the tube body.

[0017] According to the invention, it is provided that the outer shoulder part or the outer shoulder parts have / have a heating device or heating devices or are designed in such a way that they can be heated, so that the axial end section of the tube body is heated when approaching the outer shoulder part and / or when in contact with the outer shoulder part.The basic idea of ​​the invention is that when the multi-part forming tool is heated in places or sections, especially in the areas or sections that come into contact with the axial end section of the tube body or are brought closer to it, the corresponding axial end section of the tube body is preheated before and while the preform is pressed or deformed into the area of ​​the axial end section of the tube body, which in turn allows a better connection to be formed between the deformed preform or the already formed tube head and the axial end section of the tube body, even if the preform is introduced into the forming tool with a significantly lower starting temperature or initial temperature, preferably is applied to a male part of the forming tool.This allows for less energy to be applied to heat the preform to the initial temperature. At the same time, it ensures that a greater distance can be maintained between the initial temperature of the preform and critical temperatures of the material, ensuring that heating the preform to the initial temperature does not lead to degeneration, decomposition, discoloration, or other negative effects on the material that may remain in the cooled or cured tube head. The lower temperature also requires a shorter cooling time until sufficient strength is achieved and the tube can be demolded. The resulting shortened cycle time increases the throughput of the forming tool.

[0018] If the heating of the outer shoulder part is provided externally or indirectly, for example via an inductive heater, it can be provided that the processing station comprises corresponding induction means, in particular induction coils, preferably in spatial proximity to the shoulder part or parts. The induction means can advantageously be connected to the tool in such a way that they move along with the tool parts during opening and closing. This creates a minimal spacing from the area of ​​the outer shoulder part to be heated. Alternatively, it can also be provided that the induction means are moved towards the tool when the tool is closed in order to achieve the most effective heating of the relevant part of the outer shoulder part.Particularly preferably, the induction means are designed, for example by designing and influencing the spatial radiation characteristics, such that the part of the outer shoulder part in which the axial end section of the tube body is contacted by the outer shoulder part is heated / warmed in a targeted and limited manner. As already explained above, the invention provides that other regions and other sections of the multi-part forming tool, such as multi-part threaded jaws of the die, the male die, and / or an end section of the die, are further provided with cooling devices in order to achieve the fastest possible cooling of the tube head produced by pressing after the preform has been applied and the forming tool has been closed.

[0019] The forming tool can, for example, be a multi-part tool made of steel or stainless steel, or of a copper-based or copper-containing alloy. The individual components of the multi-part forming tool can include, for example, a male part for attaching or guiding the tube body and for forming an inner contour of the tube head, a single-part or multi-part outer shoulder part, a preferably multi-part outer head part or threaded part, and an outer end part, preferably with a vertically displaceable pin for forming an outlet opening in the tube head (orifice pin). However, other designs and divisions of the multi-part forming tool are also possible.According to the invention, however, it is to be realized that an outer shoulder part of the forming tool, which in itself does not necessarily have to be designed separately or apart from other parts or regions of the forming tool, but which is integrated into the forming tool in such a way that in the closed state it is arranged or will be arranged, preferably radially outward, adjacent to an axial end section of the tube body, has a preferably active heating device which ensures that the axial end section of the tube body is heated when it approaches the outer shoulder part and / or when it comes into contact with the outer shoulder part. The preform can preferably be placed centrally from an extruder as molten polymer material, for example in the shape of a ring or in the shape of a donut, onto a male mold which also holds or guides the tube body. For example, the preform can comprise or consist of HDPE.

[0020] The tube body may, for example, comprise a tube-shaped material formed into a tube shape, which has a weld seam along a longitudinal direction

[0021] The design of the casing device and the design of the heating device will be explained in more detail below. However, it can advantageously be provided that the cooling devices of the multi-part forming tool comprise at least cooling channels in the tool or in parts of the forming tool, through which a cooling medium, for example a cooling fluid, is conveyed, from which heat is extracted by a heat exchanger unit, preferably included in the cooling device, before it is introduced into the cooling channels and / or after it is led out of the cooling channels of the forming tool. Particularly preferably, the cooling device or cooling devices can form a cooling circuit with a corresponding heat exchanger.

[0022] In an advantageous embodiment of the device, it can be provided that the heating device is arranged such that, in the closed state of the forming tool, an overlap region is formed in an axial direction between the axial end section of the tube body and the heating device. It can also advantageously be provided that the heating device is arranged only in the overlap region. However, it can also be provided that the heating device extends in the axial direction beyond the overlap region, so that the heating device is also arranged in the axial direction in regions beyond the axial end section of the tube body.

[0023] This arrangement of the heating device achieves in a particularly advantageous manner that the heat acts or acts as specifically and locally as possible on the axial end section of the tube body and heats it, while at the same time not heating or not significantly heating other areas of the forming tool and / or the tube head and not weakening, or only slightly weakening, any cooling or cooling device provided there.

[0024] In an advantageous embodiment, the outer shoulder part has at least one heating device and no cooling device. This allows the previously described overlapping heating device to be implemented simply and thus cost-effectively. The overall energy consumption is also kept low or minimized by eliminating the need to heat the shoulder part in some sections and cool it in others.

[0025] In a further advantageous embodiment of the device, it can be provided that the outer shoulder part has a cooling device in a first section and a heating device in a second section. This advantageously makes it possible to specifically adapt the temperatures of the die to the requirements of the respective processing areas. In the lower region of the outer shoulder part, where the tube head is welded to the tube body, high or higher temperatures prevail, which assists the welding. In contrast, the pressed material of the preform can solidify more quickly in the upper region of the shoulder part due to the shoulder part being cooled at this point. In a particularly advantageous embodiment, it can be provided that an insulating section is formed in the outer shoulder part between the first section and the second section.This reduces the energy required to heat and cool the device compared to a design without an insulating zone. The thermal insulation between the temperature-controlled areas of the shoulder piece also prevents these two areas from reaching significantly different temperatures, preventing the tube from being processed at the desired temperatures throughout the temperature-controlled areas. In other words, without insulation, a steady and distinct temperature gradient from hot to cold would develop between the zones, meaning that the desired temperatures would not prevail in all zones.

[0026] In a further advantageous embodiment, the device is designed such that the cooling devices comprise cooling fluid channels incorporated into tool parts of the forming tool and conduits connected thereto in a fluid-conducting manner, which are configured for the circulation of a cooling fluid. This is an advantageous solution because heat can be dissipated effectively and, in particular, in a targeted manner using fluids, as demonstrated, for example, by cooling systems for internal combustion engines.

[0027] In a further advantageous embodiment, the device is designed such that the heating device comprises heat fluid channels incorporated into the outer shoulder part and fluidly connected conduits configured to circulate a heat fluid. This allows for targeted heat delivery. If the cooling device(s) are already fluid-based, existing infrastructure can also be utilized, although the circuits for the heat fluid and the cooling fluid must, of course, be designed separately. Fluid-based solutions for controlling the temperature of molds in plastics processing are proven and commonplace.

[0028] In a further advantageous embodiment, the device is designed such that the heating device comprises electrical heating means introduced into the outer shoulder part and conducting means electrically connected thereto, which are configured to supply electricity to the heating means. Alternatively, the device is designed such that it can be heated inductively. Electrical or inductive heating can be advantageous because, as direct heating of the tool, it can be controlled more quickly, easily, and precisely than indirect heating using a heating fluid. It can also be switched off more quickly than heating using a heating fluid, in which the hot fluid in the channels continues to heat the device even when the fluid circulation is switched off. The heating can thus also be carried out very close to the surface, which further improves the controllability of the temperature in the processing space of the device.Furthermore, the components required for a fluid circuit, such as a pump, storage and / or expansion tank, sensors for monitoring a heat fluid leak, etc., are omitted. The implementation of the invention with an electric heater also requires less maintenance because no heat fluid needs to be replaced and because no moving pipe elements or valves, pumps, etc. can wear out.

[0029] In a further advantageous embodiment, the device is designed such that it comprises a multi-part re-pressing tool forming a second processing station, with a preferably one-part head part. The head part, when the re-pressing tool is closed, is also arranged adjacent to an axial end section of the tube body, and comprises a cooling device that is also configured to cool the axial end section of the tube body. This cooled re-pressing tool accelerates the solidification of the tube material and ensures that it solidifies consistently and in the desired shape in each of the countless repetitions of the process.

[0030] This shape is particularly important for the function of the thread, for example. The re-pressing tool can be used to apply additional pressure to the shoulder area during cooling, allowing the weld seam in particular to solidify under controlled conditions, thus ensuring consistent weld quality.

[0031] While the present invention initially comprises a device which can realize the advantages described above, it is nevertheless also encompassed by the invention to provide an operating method which describes in particular the operation of the tool according to the invention, but in principle also beyond this and independently an advantageous method for producing a packaging tube consisting of a tube head and a tube body.

[0032] In connection with the method according to the invention, it is intended to proceed in the following order or sequence of process steps:

[0033] A preform and a tube body are introduced into the open, multi-part forming tool, which forms the first processing station. The tool is then closed, and during this transition, the tube head is formed from the preform, and the connection between the tube head and the tube body is established. The forming tool contains cooling devices with which it is cooled, at least in the closed state, and it comprises an outer shoulder part, which, when the forming tool is closed, is preferably arranged radially outward and adjacent to an axial end portion of the tube body.This outer shoulder part comprises a heating device or is heated from the outside, so that on the one hand the axial end section of the tube body is heated when approaching the shoulder part and / or when in contact with the shoulder part and on the other hand the cooling of the inflowing shoulder material in the region of the axial end section of the tube body is slowed down.

[0034] In an advantageous extension of the method according to the invention, after shaping, the workpiece, consisting of the tube body and the tube head formed thereon and thus connected thereto, can be transferred from the first processing station to a re-pressing tool as the second processing station. In the closed state, a head part of the re-pressing tool lies adjacent to an axial end section of the tube body and cools this by means of the cooling device arranged in the head part. Particularly preferably, the shoulder section of the head part is cooled. The re-pressing tool, like the shaping tool, can comprise a multi-part tool, for example made of stainless steel or a copper-containing alloy, which can more preferably be transferred at least into a closed state and an open state. In the open state, a tube produced in the shaping tool and removed from it can be received and removed.For this purpose, individual parts of the pressing tool can be designed to be movable or displaceable.

[0035] In a second advantageous extension of the method according to the invention, the heating device of the forming tool can be arranged such that an overlap region is formed in the axial direction between the axial end section of the tube body and the heating device.

[0036] Further advantages, features, and details of the invention are described below by way of example with reference to the schematic drawings. These show:

[0037] Fig. 1 : a sectional view of a forming tool for producing a plastic tube according to the prior art

[0038] Fig. 2: a sectional view through a male part of the forming tool with inserted tube body and applied preform

[0039] Fig. 3: a sectional view through a forming tool of the device according to the invention for producing a plastic tube in a first embodiment

[0040] Fig. 4: a sectional view through a shaping tool of a device according to the invention in a second embodiment

[0041] Fig. 5: a sectional view through a shaping tool of a device according to the invention in a third embodiment

[0042] Fig. 6: a sectional view through a shaping tool of a device according to the invention in a fourth embodiment

[0043] Fig. 7a: a sectional view through a shaping tool of a device according to the invention during the method according to the invention at a first time Fig. 7b: a sectional view through a shaping tool of a device according to the invention during the method according to the invention at a later time

[0044] Fig. 7c: an enlarged section of the illustration in Fig. 7b, showing the connection between the tube body and the tube head

[0045] Fig. 8: a sectional view of part of a pressing tool for producing a plastic tube

[0046] The illustrations are schematic and simplified; for example, means for moving and holding the tool parts are not shown. Identical elements or features are provided with the same reference numerals.

[0047] Fig. 1 shows the sectional view of a multi-part forming tool 1 according to the prior art, consisting of the multi-part die 2 and the patrix 3.

[0048] The dashed line 16, which is only shown in the left half of the illustration, shows that the die is movable in the neck area. This allows the forming tool 1 to be converted into a closed and an open state. The sequence for closing and opening the forming tool 1 is as follows: Close the neck area, as indicated by dashed line 16, then bring the die 2 and the male part 2 closer together in a linear manner relative to one another, open the neck area, and then move the die 2 and the male part 2 away from one another in a linear manner. The mobility of the die in the neck area is crucial so that the produced plastic tube 19 can be removed from the forming tool 1 without destroying areas of the plastic tube with undercuts. In the closed state, a cavity or hollow space 17 is formed between the parts of the forming tool 1, in which cavity the tube head can be formed and connected to the tube body.In the open state of the forming tool 1 (not explicitly shown but indicated), the tube body can be slipped over the male mold 3 at the beginning of the process. After completion of the process, the tube can be demolded or removed from the mold in the open state of the forming tool 1. In a neck region 18, the female mold is cooled by the cooling device 6. The same applies to the outer shoulder part 7 and to the male mold 3 (not shown). The cooling devices can comprise conformal cooling channels and can be supplied with a cooling fluid in order to dissipate heat from the respective parts of the forming tool. This accelerates the solidification of the preform. At the same time, however, a high starting temperature or initial temperature of the preform is required.

[0049] In the right half, Figure 1 shows the cross-section of the tube 19 after processing. To produce the tube, as shown in Figure 2, the cold tube body 5 and the hot preform 4 are introduced into the open forming tool 1. The forming tool 1 is closed or converted into the closed state, thereby compressing the plastic preform 4. The tube head of the tube is thus formed from the preform. Due to the high temperature of the preform, a weld is created with the tube body in the overlap area 8. The cooled die and die cool the tube so that the material solidifies and the tube can be removed from the forming tool after the tool has been converted back into the open state. The disadvantage here is that the preform must be introduced so hot that the temperature is sufficient to create the weld before the cooled tool parts have dissipated the heat.As already mentioned, Fig. 2 shows how the tube body 5 and the preform 4 are introduced for processing, both in the prior art and in the invention. The tubular tube body 5 is pushed onto the cylindrical male mold 3, and the preform 4 is placed centered on the collar 20. The tubular tube body 5 (horizontally hatched) can be seen around the male mold 3, and the annular preform 4, also called a donut, rests on the collar 20 of the male mold 3. The preform 4 can, for example, be dispensed from or applied to an extruder with an annular opening (not shown).

[0050] Fig. 3 shows a first embodiment of the forming tool 1 of the device according to the invention with a cooling device 6, for example in the neck region 18 and the heating device 9 in the outer shoulder part 7. The heating device 9 is positioned such that the overlap region 8 is heated, which overlaps with the axial end section (cf.: Figures 7b and 7c) of the tube body (23) in the axial direction A when the forming tool 1 is closed. The heating device 9, which can also comprise contour-hugging heating channels, facilitates the welding of the preform to the tube body because, on the one hand, the edge section of the tube is preheated and, on the other hand, the preform cools less quickly in this region, so that the preform can be introduced into the tool at a lower temperature.This has the following beneficial effects, which are not exhaustive: thermal decomposition processes in the plastic of the preform in the extruder are significantly slowed or even prevented, less energy is required for heating and cooling, and the cooling time required to reach a target temperature in the cooled areas is shortened, thus reducing cycle times. This enables gentler and more energy-efficient processing.

[0051] Fig. 4 shows a second advantageous embodiment of the forming tool 1. A cooling device 6 in the shoulder part 7 is implemented by means of the cooling fluid channels 11, and a heating device 9 in the shoulder part 7 is implemented by heating fluid channels 12. An insulating section 10 is located between the cooled, first section 21 and the heated, second section 22 of the shoulder part 7. The insulating section 10 can, for example, be formed from a separate thermally insulating material. Alternatively, the insulating section can be implemented by a material or structural change in the material of the shoulder part 7. The advantage of this is that the thermal insulation means that the tempered sections have little or no mutual influence, which reduces the energy required for tempering and ensures a more uniform temperature in the sections.

[0052] Fig. 5 shows a third advantageous embodiment of the forming tool 1. The heating device of the shoulder part 7 is designed as an electrical heating means 13. The embodiment with the electrical heating means 13 can also be combined with the embodiment of Fig. 4, in which an insulating section and / or a cooling device is formed in the shoulder part 7 (see Figure 6). The electrical heating means can, for example, comprise heating resistors that generate and release heat when energized.

[0053] Fig. 6 shows a fourth advantageous embodiment of the forming tool 1. The heating device is designed as an electric heating means 13, wherein the heated, second section 22 of the tool is thermally decoupled from the cooled, first section 21 of the shoulder part 7 with the cooling fluid channels 11 by the insulating section 10. This embodiment thus combines the advantages of the two preceding embodiments.

[0054] Fig. 7a shows a forming tool 1 during the method according to the invention. The method step shown in Figure 7a can follow the method step shown in Figure 2. In the illustration in Figure 7a, the forming tool 1 is transferred into the closed state. The preform 4 is already partially pressed, while the tube body 5, in particular the axial end section 23, has not yet been formed or folded into the overlap region 8. It is clear that the geometrically complex head section (for example, having an external thread) is produced by plastic deformation of the hot preform. Already in the situation in Figure 7a, heat transfer and preheating of the axial end section 23 can take place due to the approach between the heating device 13 and / or the shoulder part 7 and the axial end section 23 of the tube body 5.With increasing proximity of the axial end portion 23 and the shoulder part 7 and / or the heating device 13, the heat transfer is improved and increased.

[0055] Fig. 7b shows a forming tool 1 in the closed state during the process according to the invention. The preform 4 is completely formed, and the axial end section 23 of the tube body 5 is folded into the overlap region 8. The first section 21 of the outer shoulder piece 7 is cooled by means of the cooling fluid channels 11, thus accelerating the solidification of the formed preform 8. The overlap region 8 is shown in an enlarged view in Fig. 7c.

[0056] Fig. 7c shows an enlarged section of the overlap area

[0057] 8 in the forming tool 1. The electrical heating means 13 specifically heat this area, in which the axial end section 23 of the tube body is also arranged, so that the production of the welded connection between the preform formed into the tube head and the tube body is supported.

[0058] Figure 8 shows a post-pressing tool 14, which can be part of a second processing station of the device according to the invention. The shaping tool 1 of Figures 1 to 7c is advantageously part of a first processing station of the device. Similar to the shaping tool, the post-pressing tool can be converted into an open and a closed state. The open state allows insertion and removal of a tube, and the closed state allows cooling of the tube, preferably the tube head.

[0059] The re-pressing tool 14 can be cooled by means of a cooling fluid that is guided through the conformal cooling fluid channels 24. Cooling the re-pressing tool 14 accelerates and controls the cooling and solidification of the previously formed tube, particularly the tube head. The pressure on the tube, particularly on the welded joint in the overlap area 8, ensures that the tube solidifies in the desired shape and that the welded joint remains securely connected until it is sufficiently cool and thus solid.

[0060] List of reference symbols

[0061] 1 . Shaping tool

[0062] 2. Multi-part die

[0063] 3. Patrize / stamp

[0064] 4. Preform (vertically hatched)

[0065] 5. Tube body (horizontally hatched)

[0066] 6. Cooling device of the forming tool

[0067] 7. Outer shoulder part

[0068] 8. Overlap area of ​​preform and tube body

[0069] 9. Heating device

[0070] 10. Insulation section

[0071] 11 . Cooling fluid channels

[0072] 12. Heat fluid channels

[0073] 13. Electric heating

[0074] 14. Re-pressing tool

[0075] 15. Cooling device of the repressing tool

[0076] 16. Dashed line showing the mobility of the matrix

[0077] 17. Cavity of the forming device

[0078] 18. Neck area of ​​the matrix

[0079] 19. Manufactured plastic tube

[0080] 20. Collar of the patrix

[0081] 21 . Cooled first section of the forming tool

[0082] 22. Heated second section of the forming tool

[0083] 23. Axial end section of the tube body

[0084] 24. Cooling fluid channels of the re-pressing tool

[0085] Axial direction A

Claims

Patent claims 1. A device for forming a tube head by pressing a preform (4) and connecting the tube head to a tube body (5) to produce a packaging tube, comprising a multi-part forming tool (1) forming a first processing station, in particular comprising a male mold (3) and a multi-part die (2), into which a preform (4) and a tube body (5) can be introduced in an open state and which, upon transition to a closed state, forms the tube head from the preform (4) and establishes the connection to the tube body (5), wherein the forming tool has cooling devices (6) with which parts of the forming tool (1) can be cooled, wherein the forming tool (1) further comprises an outer shoulder part (7) which, in the closed state, is arranged, preferably radially outward, adjacent to an axial end portion (23) of the tube body (5), characterized inthat the outer shoulder part (7) has a heating device (9, 12, 13) or can be heated from the outside, so that the axial end section (23) of the tube body (5) is heated when approaching the outer shoulder part (7) and / or when in contact with the outer shoulder part (7).

2. Device according to claim 1, characterized in that the heating device (9) is arranged so that in the closed state in an axial direction (A) a Overlap area is formed between the axial end portion of the tube body (23) and the heating device (9).

3. Device according to claim 1 or 2, characterized in that the outer shoulder part (7) has only at least one heating device and no cooling device.

4. Device according to one of the preceding claims, characterized in that the outer shoulder part (7) has a cooling device in a first section (21) and a heating device in a second section (22).

5. Device according to claim 4, characterized in that an insulating section (10) is formed in the outer shoulder part (7) between the first section (21) and the second section (22).

6. Device according to one of the preceding claims, characterized in that the cooling devices comprise cooling fluid channels (11) introduced into tool parts of the shaping tool (1) and conduit means connected thereto in a fluid-conducting manner, which are designed to circulate a cooling fluid.

7. Device according to one of the preceding claims, characterized in that the heating device (9) has heat fluid channels (12) introduced into the outer shoulder part (7) and thus fluid-conducting connected piping means arranged to circulate a heat fluid.

8. Device according to one of claims 1 to 7, characterized in that the heating device comprises electrical heating means (13) introduced into the outer shoulder part and line means electrically connected thereto, which are arranged to supply the heating means with electricity.

9. Device according to one of the preceding claims, characterized by a multi-part re-pressing tool (14) forming a second processing station with a, preferably one-part, head part, wherein the head part is also arranged adjacent to an axial end section of the tube body (23) in a closed state of the re-pressing tool (14) and comprises a cooling device (15) which is also designed to cool the axial end section of the tube body (23).

10. A method for forming a tube head by pressing a preform and connecting the tube head to a tube body to produce a packaging tube, comprising the method steps: Inserting a preform and a tube body into a multi-part forming tool in the open state, forming a first processing station -Closing the forming tool, wherein during a transition to a closed state the tube head is formed from the preform and the connection to the tube body is established, wherein the forming tool Has cooling devices with which parts of the shaping tool are cooled, at least in the closed state, wherein the shaping tool comprises an outer shoulder part which, when the shaping tool is closed, is arranged, preferably radially outwardly, adjacent to an axial end section of the tube body, characterized in that the axial end section of the tube body is heated when approaching the outer shoulder part and / or when in contact with the outer shoulder part, preferably with a heating device encompassed by the outer shoulder part.

11. Method according to claim 10, characterized by the tube head connected to the tube body is transferred from the first processing station to a second processing station and is processed with a multi-part re-pressing tool included in the second processing station, wherein a head part in a closed state of the re-pressing tool cools the axial end section of the tube body with a cooling device arranged in the head part adjacent to an axial end section of the tube body.

12. The method according to claim 10 or 11, characterized in that the heating device is arranged so that when the forming tool is closed in an axial direction, an overlap region is formed between the axial end portion of the tube body and the heating device

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