Device and method for molding a tube head blank of a tube blank

Abstract

The invention relates to a device (1) for molding a tube head blank (2a) of a tube blank (2) such that a tube blank is produced with a completed tube head (2c). The device comprises a lower tool (3) having a lower tool body (3a) and a free end (3b) which has an outer shape that corresponds to the inner shape of the completed tube head, wherein the tube blank can be placed on the lower tool such that the tube head blank to be molded comes to rest about the free end. The device additionally comprises an upper tool (4) which can be lowered onto the lower tool with the tube blank placed thereon. The upper tool has an upper head end piece (5) with molding jaws (5a) which together form a first recess (6) that defines the outer shape of the completed tube head. The upper head end piece comprises an actuation device (5c, 7) for opening and closing the molding jaws. The device additionally has a temperature-control system for heating the upper tool to an intended temperature. The tube head blank comes to rest in the first recess and can be molded between the closed molding jaws and the free end of the lower tool in order to form the completed tube head.

Description

[0001] Device and method for forming a

[0002] Tube head blank of a tube blank

[0003] Reference to related documents

[0004] This document claims priority from Swiss patent application No. CH000638 / 2023, filed on June 15, 2023, the entire contents of which are hereby incorporated by reference.

[0005] Field of the invention

[0006] The invention relates to a device and a method for forming a tube head blank of a tube blank made of plastic according to the respective independent claim.

[0007] background

[0008] It is known to provide plastic tubes with a tube head. In this case, a tube blank is either manufactured with a tube head blank in one piece, or the tube head blank is manufactured separately and typically extruded, compression-molded, formed, or ultrasonically or high-frequency welded to the tube blank. The structure thus produced is then further processed, for example by closing the lower end of the tube blank and forming the tube head from the tube head blank. Further steps such as printing the tube body can follow.

[0009] There are a variety of processes for producing such a tube, which can be made from a variety of thermoplastic materials such as polyethylene, polyvinyl chloride, polypropylene, etc. One challenge when manufacturing the finished tube is attaching and molding the tube head, which provides access to the tube contents and must be closable. Methods have been used to mold a tube head and then connect it to the tube body. These processes were cumbersome, and connecting the tube head to the tube body was problematic. These processes have been improved by connecting a tube head blank that had not already been molded to the tube body and only then is the tube head molded on. Alternatively, the tube blank was manufactured in one piece with the tube head blank, e.g.as a simple cylinder, and then the tube head was formed on, which eliminated the molding step and simplified production. The most common variant is to mold the head (die casting or injection molding). Both alternatives are still used. For example, with the tube blank which is made in one piece with the tube head blank, a device with an upper tool and a lower tool is provided. The blank is placed over the lower tool and the upper tool is lowered onto it. By appropriately designing the upper and lower tools and heating the upper tool, the tube head blank is pressed between these two and heated in the process, so that it is shaped accordingly. The upper tool and lower tool can close and form the tube head blank without the upper tool being lowered.

[0010] Description of the invention

[0011] The task to be solved is to simplify the forming of tube heads from tube head blanks and to make it more flexible.

[0012] The object is achieved in a first aspect of the invention by means of a device for forming a tube head blank of a tube blank according to claim 1. The tube head blank can be integral with the tube body of the tube blank or fastened to the tube body of the tube blank. Accordingly, the device comprises a lower tool with a lower tool body and an upwardly projecting free end which has an outer shape which corresponds to a intended inner shape of the finished tube head. The tube blank can be put over the lower tool so that a longitudinal axis of the lower tool and a longitudinal axis of the tube blank are identical and the tube head blank to be formed comes to lie around the free end. Furthermore, the device comprises a temperature-controlled upper tool whose longitudinal axis is identical to the longitudinal axis of the lower tool. The upper tool can be moved back and forth along the longitudinal axis.The lower tool, with the tube blank slipped over it, can be received in an upper tool body of the upper tool. The upper tool has an upper head end piece with at least two openable and closable mold jaws, which together form a first recess centered with respect to the longitudinal axis, which recess defines an outer shape of the finished tube head when the mold jaws are in the closed position and is diametrically larger when the mold jaws are in the open position than when the mold jaws are in the closed position. The upper head end piece further comprises an actuating device for opening and closing the mold jaws. The device also comprises a temperature control system for heating the upper tool.The upper tool can be lowered onto the lower tool or the lower tool can be raised into the upper tool in such a way that the tube head blank comes to lie in the first recess in the open position of the mold jaws and can be formed into the finished tube head between the closed mold jaws and the free end of the lower tool.

[0013] The object is achieved in a second aspect of the invention by means of a method for molding a tube head blank onto a tube blank according to the corresponding independent method claim. The method is carried out using a device according to the first aspect of the invention. One advantage of the invention is that, due to the use of closable and openable mold jaws, the diameter of the first recess can be varied. Because the diameter of the first recess is larger in the open position than in the closed position, it is easier to insert the tube head blank therein without having to worry about compression or generally undesirable deformations that could possibly affect the final shape of the tube head or the entire tube blank.

[0014] A further advantage of the invention is that the device can be easily adapted to different materials of the tube head blanks by adjusting the heating temperature of the upper tool.

[0015] The fact that the device is adapted for processing tube blanks with tube head blanks results in a further advantage: the device does not need to be designed to take into account the risk of leakage at a seam between the tube body and the tube head during processing. This also eliminates the need for any leak testing after the forming process.

[0016] Short description of the drawings

[0017] Further embodiments, advantages, and applications of the invention will become apparent from the dependent claims and the following description with reference to the figures. In these figures:

[0018] Fig. 1 sectional views of the device according to the invention showing a manufacturing sequence in partial images,

[0019] Fig. 2 shows sectional views of the device according to the invention from Fig. 1, which show in partial images the release of a tube blank with a finished tube head, Fig. 3 shows a sectional view of the upper tool of the device from Fig. 1 in a preferred embodiment during the lowering of the upper tool,

[0020] Fig. 4 is a sectional view of the upper tool of the device from Fig. 1 in a preferred embodiment when lifting the upper tool to release the tube blank with the finished tube head,

[0021] Fig. 5 is a plan view of the upper tool from Fig. 4,

[0022] Fig. 6 is a plan view of the upper tool from Fig. 3,

[0023] Fig. 7 is a side view of an exemplary tube blank with a tube head blank, and

[0024] Fig. 8 is a side view of the tube blank from Fig. 7 with the tube head already formed.

[0025] Ways to implement the invention

[0026] In the present case, the term "tube blank" encompasses plastic containers in the form of tubes, typically for toothpaste, lotions, in the cosmetics, dental, and pharmaceutical sectors, etc., and refers to the entire tube. The tube blanks can be made of a wide variety of polymer materials, such as polyethylene, polypropylene, or renewable or recycled materials. The suffix "-blank" in this term is intended merely to indicate that these do not necessarily have to be tubes with a finished tube body, but that, after the invention, which is directed at the formation of the tube head, further steps for processing the tube body can take place. For example, steps such as closing the tube base, printing the tube body, etc. can follow. However, it is irrelevant for the present invention whether the tube body is finished or not.In practice, however, the invention is preferably applied to an unprocessed tube blank. Accordingly, a distinction is made here between "tube head blank" and "finished tube head" or "finished, molded tube head." The first term denotes the state before molding, and the other terms denote the state after molding, as shown in Fig. 7 and 8, respectively.

[0027] In this context, the term "tempering" is to be understood as encompassing both heating and cooling. However, it is not absolutely necessary for a tempering system to be capable of cooling. The main task of such a system as intended here is heating.

[0028] The terms "irreversibly moldable" and "shape-stable" are to be understood here in such a way that the final shape of the tube head retains its intended shape without external influences, e.g. heat.

[0029] Fig. 1 shows sectional views of a device according to the invention, illustrating a manufacturing sequence in partial images. The horizontal dotted-dashed line N indicates a reference plane to clarify the vertical position of the elements of the device during the various steps. To simplify the figures, the reference symbols are not repeated in all figures or partial figures.

[0030] Partial image a shows the device 1 for forming a tube head blank 2a onto a tube blank 2 (Fig. 7), resulting in a tube blank with a finished tube head 2c (Fig. 8). The device comprises a lower tool 3 with a lower tool body 3a and an upwardly projecting free end 3b which has an outer shape which corresponds to a desired inner shape of the finished tube head. The lower tool body is typically cylindrical. The tube blank 2 can be slipped over the lower tool so that a longitudinal axis x of the lower tool and a longitudinal axis of the tube blank are identical and the tube head blank to be formed comes to lie around the free end, as shown in Fig. 1a. Adjoining the free end 3b is a shoulder 3c which forms the later transition between the tube head and the tube body.This also explains why, in the illustration shown, the tube head blank protrudes significantly beyond the free end, since this shoulder must also be taken into account when determining the length. In some embodiments, it can be provided that the length of the free end 3b up to the connection to the shoulder 3c can be varied by pushing the free end further or further out of the lower tool body. This allows the device to be adapted to longer or shorter tube heads without having to change the entire lower tool.

[0031] The device further comprises a temperature-controlled upper tool 4, the longitudinal axis of which is identical to the longitudinal axis x of the lower tool. The upper tool can be moved back and forth along the longitudinal axis x, so that the lower tool with the tube blank slipped on can be received in an upper tool body 4a of the upper tool. The upper tool has an upper head end piece 5 with at least two openable and closable mold jaws 5a (Fig. 3, 4), which together form a first recess 6 centered in relation to the longitudinal axis. When the mold jaws are in a closed position, the recess defines an outer shape of the finished tube head. When the mold jaws are in an open position, the recess is diametrically larger than when the mold jaws are closed. The upper head end piece further comprises an actuating device 5c, 7 (Fig. 3, 4) for opening and closing the mold jaws.

[0032] In partial image 1b you can see how the upper tool has been lowered onto the lower tool and how this is accommodated in the upper tool body. At the head end piece you can see a gap 9 which is intended to clarify that the mold jaws are still in the open position. The functioning of the mold jaws with the actuating device is explained in more detail in connection with Figs. 3 and 4. The tube head blank comes to rest in the first recess in the open position of the mold jaws.

[0033] In the partial image lc the mould jaws are closed, which is illustrated by the fact that the gap 9 has disappeared from the partial image 1b.

[0034] In partial image 1d, one can see how the upper tool has been lowered further (see line N) and the tube head blank has been received in the recess 6. The forming process has begun. For this purpose, the device has a temperature control system (not shown) for heating the upper tool so that the thermoplastic material of the tube head blank can be formed by cold forming.

[0035] Finally, the partial image 1e is intended to indicate that the upper tool remains in the lowered, intended end position for a specific period of time until the forming of the tube head blank into the finished tube head is complete. This specific period of time is necessary so that the thermoplastic material becomes sufficiently deformable so that it can assume the intended shape of the tube head between the closed mold jaws and the free end of the lower tool.

[0036] Fig. 2 shows sectional views of the device according to the invention from Fig. 1, illustrating in partial images the release of the tube blank with the finished tube head. The starting position in partial image 2e corresponds to partial image 1e.

[0037] Part 2f shows how the demolding process begins, or in other words, the release of the tube blank with the finished tube head. The mold jaws have already been opened, as indicated by gap 9.

[0038] In part 2g the upper tool can be seen lifting and releasing the tube blank with the finished tube head.

[0039] Partial image 2h corresponds to part la and shows the upper tool in its raised initial position, with the difference that here the tube blank with the finished tube head can be seen, whereas in part la the tube blank with the tube head blank can be seen.

[0040] Fig. 3 shows a sectional view of the upper tool of the device from Fig. 1 in a preferred embodiment when lowering the upper tool and Fig. 4 when raising the upper tool to release the tube blank with the finished tube head.

[0041] The mold jaws 5a can be moved radially to the longitudinal axis x for closing and opening, so that the free end of the lower tool with the tube head blank can be enclosed from the side by the mold jaws and that in the open position of the mold jaws the free end of the lower tool with the finished tube head can be released. In Fig. 3 the closing of the mold jaws is indicated by the inward-pointing horizontal arrows, while in Fig. 4 the opening of the mold jaws is indicated by the outward-pointing horizontal arrows. It is preferred if exactly three mold jaws are provided. Of course, only two or more than three mold jaws can also be provided.

[0042] As mentioned, an actuating device is provided for opening and closing the mold jaws. This preferably comprises a spring system with a plurality of springs 7, which are arranged such that they are relaxed in the open position of the mold jaws and tensioned in the closed position of the mold jaws. The springs 7 are oriented such that they press the mold jaws radially outward in the tensioned state. In other words, a rest position of the mold jaws corresponds to the open position in which the springs are relaxed.

[0043] The actuating device preferably further comprises a retaining element 5c which can be moved back and forth in the x-direction. The retaining element serves to hold the mold jaws in the closed position when the springs are tensioned. The retaining element is preferably a cover, in particular a one-piece cover, which has a second recess in which the mold jaws can be at least partially received. However, the retaining element could also be designed differently in order to hold the springs of the spring system in the tensioned state. For example, it could be one or more elements which act on the mold jaws from the side radially towards the longitudinal axis.

[0044] In some embodiments, the mold jaws each have an inclined surface F on the outside, so that in the closed position they have the shape of a truncated cone towards the top. In other words, they taper towards the top. The cover 5b has a correspondingly inclined counter-surface. When the cover is lowered towards the mold jaws (Fig. 3), the counter-surfaces interact with the inclined surfaces F of the mold jaws in the open position of the mold jaws by sliding down the inclined surfaces F, which is possible due to the degree of freedom of horizontal movement of the mold jaws. The springs are compressed, so that the mold jaws can be compressed radially towards the longitudinal axis x into the closed position. To open the mold jaws (Fig.4 ) the lid can be raised accordingly, whereby the springs press the mold jaws radially away from the longitudinal axis x and these move from the closed position into the open rest position. It should be noted that the lowering of the upper tool as already described does not correspond to the lowering of the lid. In other words, the lowering of the upper tool causes the tube head to form and the lowering of the lid causes the mold jaws to close. An advantage of the solution with the interacting surfaces F and the counter surfaces during demolding is that the opening process of the mold jaws is continuous.In contrast to a solution which is also possible but not preferred, in which the mould jaws are opened abruptly, in this case the detachment of the mould jaws from the moulded tube head takes place "gently" so that any areas of the tube head which may still be adhering to the inner wall of the mould jaws due to the heating can be removed slowly and without cracks.

[0045] A further recess 5b is provided in the lid, which serves as an expansion space for any excess material when forming the tube head.

[0046] The gap 9 mentioned is now more clearly visible in Fig. 3 and illustrates that when the lid is lowered it is lifted from the head end piece 5, whereby in the closed position of the mold jaws the lid can rest on the head end piece, which is not absolutely necessary, however, and is assumed to be the case in Figs. 1 and 2 for illustration purposes. In Fig. 4 the gap is shown larger in order to clarify the lifting of the lid.

[0047] The head end piece preferably itself has a counter-shape to the aforementioned shoulder 3c (Fig. 1a) of the lower tool in order to form the shoulder of the tube blank between the tube head and the tube body. In other words, the head end piece 5 tapers on the inside, starting from the upper tool body 4a, in the direction of the first recess, so that the tube head blank can be inserted into the first recess as the upper tool is increasingly lowered, compressing the tube head blank, until it reaches a predetermined end position. These inclined surfaces 5e advantageously also serve to gently taper the upper edge of the normally cylindrical tube head blank as it is inserted into the recess 6, so that the edge is prevented from getting caught and potentially causing a kink.

[0048] In some embodiments, the inner shape of the mold jaws is such that, in their closed position, a suitable external thread 10 can be formed in the outer shape of the tube head blank, resulting in a finished tube head with an external thread. This allows the tube to be easily closed and opened with a tube cap.

[0049] In this context, it is preferred if the mold jaws are interchangeable with alternative mold jaws whose internal shape is different. This makes it possible to achieve different external threads or generally a different external shape of the tube head for different requirements. In embodiments, it can be provided that the number of mold jaws can vary, i.e. for example, instead of a set with two mold jaws, a set with three mold jaws is used. Irrespective of the number of mold jaws, it is also preferred if the device comprises a plurality of sets of interchangeable mold jaws, which can be selected at least from the following group of mold jaws: mold jaws for tube heads with external threads, mold jaws for tube heads for snap closures, mold jaws for tube heads for impact closures, mold jaws for tube heads for shoulder closures.Other types of closures, including special closures, can also be produced with the device. These alternatives regarding the number and internal shape of the mold jaws advantageously allow the device to be easily converted to produce a variety of tubes with different tube heads by simply exchanging the mold jaws.

[0050] Fig. 5 shows a plan view of the upper tool from Fig. 4 and Fig. 6 a plan view of the upper tool from Fig. 3 . In each case, the cover 5c is not shown. These figures serve to clarify the design of the mold jaws 5a in interaction with the springs 7. In the middle, the recess 6 can be seen in which the tube head blank comes to rest. The free end 3b of the lower tool can also be seen. The black circular area in the figures represents the gap between the mold jaws and the free end of the lower tool, in which the tube head blank comes to rest and in which the tube head is formed.

[0051] In general, the device preferably comprises a first drive for translationally displacing the upper tool and / or the lower tool back and forth along the longitudinal axis (x). It is noted that, by way of example, it is described here that the upper tool can be lowered onto the lower tool. Although this embodiment is preferred, the lower tool could alternatively be liftable such that it penetrates into the upper tool body from below until it reaches the intended position. A combination of these two alternatives is also conceivable, in which the upper tool and the lower tool are moved towards one another.

[0052] It is further preferred if the first drive is not designed for a rotary movement of the upper tool and / or the lower tool about the longitudinal axis (x). This allows the first drive to be designed more simply. Due to the lateral engagement of the tube head blank by the mold jaws, an external thread can be formed simply by pressing.

[0053] In some embodiments, the device comprises a second drive for translationally displacing the retaining element back and forth along the longitudinal axis x. However, it can also be provided that the first drive also performs this task.

[0054] Fig. 7 shows a side view of an exemplary tube blank with a tube head blank and Fig. 8 shows a side view of the tube blank from Fig. 7 with the tube head already formed.

[0055] The tube head blank is formed in the following steps: a) The tube blank with the tube head blank is slipped over the lower tool so that the tube head blank comes to rest around the free end of the lower tool and the tube body rests against the lower tool body. It is possible to provide different lower tools for different tube sizes, in particular with different diameters or lengths. b) The upper tool with open mold jaws is lowered onto the lower tool equipped with the tube blank to a first position in which the tube head blank comes to rest in the first recess. c) The mold jaws are closed. d) The upper tool is lowered further to a final position in which the tube head is formed while the tube head blank is heated to a specified temperature.The final position corresponds to the position in which the shoulder between the tube head and the tube body is also taken into account, i.e. until the shoulder 3c of the lower tool and the inclined counter-mold 5e are only separated by the distance which corresponds to the intended thickness of the tube.

[0056] The tube head blank remains in this final position for a certain time so that the heat can act on the material and the cold forming is completed. It is preferred if the temperature control system is designed to heat the head end piece of the upper tool or the entire upper tool to a first temperature which corresponds to the intended temperature at which the tube head blank can be irreversibly formed into the finished tube head by cold forming. The upper tool can be heated either before it is lowered onto the lower tool or after it has been lowered onto the lower tool. For this purpose, the temperature control system comprises corresponding heating means which are arranged, for example, inside the upper tool.In embodiments, the temperature control system can also be designed to heat the free end of the lower tool or the entire lower tool to a third temperature, at which the tube head blank can be irreversibly formed into the finished tube head by cold forming. In other words, heating of the tube head blank can be assisted by the lower tool in addition to heating by the upper tool. In such an embodiment in which the temperature control system is designed to heat the lower tool in addition to heating the upper tool, it is preferred if the first temperature is higher than the third temperature.Advantageously, the third temperature is only high enough to warm the tube head blank, preferably before it enters the recess, thus facilitating entry into the recess, but not so high that the freely projecting tube head blank collapses before entering the recess. Preheating the tube head blank shortens the time required for its dimensionally stable final formation in the recess.

[0057] In embodiments, the tempering system is designed to cool the head end piece of the upper tool or the entire upper tool to a second temperature, so that the tube blank with the molded-on finished tube head can be removed from the device in a dimensionally stable manner.

[0058] Additionally or alternatively, the tempering system can be designed to cool the free end of the lower tool or the entire lower tool to a fourth temperature, so that the tube blank with the molded-on finished tube head can be removed from the device in a dimensionally stable manner.

[0059] To cool the upper and / or lower tool, the temperature control system can, in a known manner, have means for air cooling or liquid cooling. This is known and will not be explained in detail here. The device further comprises a controller for controlling the drive or drives for moving the upper tool and / or the lower tool along the longitudinal axis x, in particular for controlling the lowering depth and / or the lifting height. The controller is also designed to regulate the above-mentioned temperatures. For this purpose, it is connected to corresponding temperature sensors on the upper and lower tools and controls the temperature control system depending on the sensor data. Furthermore, the length of the corresponding production sequences, e.g. residence time during forming, etc. can be programmed into the controller. The programming or reprogramming of the above-mentionedParameters and other parameters are advantageous so that the device can be flexibly adapted to different requirements. For example, the dwell time during forming can vary depending on the temperature and material of the tube head blank. Alternatively, the dwell time could also be controlled by curved paths.

[0060] Preferably, a valve (not shown) is arranged in the lower tool body or in the free end of the lower tool, and a compressed air line is provided which is connected to the valve and preferably runs inside the lower tool body and is connected to a compressed air compressor arranged outside the lower tool. The compressed air compressor can be a conventional compressor and is preferably part of the device. However, it does not have to be part of the device. The valve is closed during the forming of the tube head blank and is opened after the forming by means of compressed air led from the compressed air compressor through the compressed air line, so that the compressed air can flow between the lower tool and the fitted tube blank with the finished tube head. When the lower tool is removed from the tube blank or vice versa, this assists the detachment of the tube blank from the lower tool.It is preferred if the valve is oriented such that the direction of the compressed air flow from the valve not only detaches the tube blank but also lifts it from the lower tool. This is advantageous for making it easier to remove the tube blank from the lower tool using a suitable gripping device.

[0061] It is preferred if the compressed air is cooled by means of the temperature control system before it is blown between the lower tool and the fitted tube blank. This supports or effects the aforementioned cooling to the fourth temperature.

[0062] The present invention makes the molding of tube head blanks more flexible by enabling the adjustment of various parameters such as heating temperature, thus ensuring compatibility with different tube head materials. The described options allow for further degrees of freedom, such as the exchange of mold jaws, which allows for the production of various tube head configurations, e.g., with different closure types and different diameters.

[0063] While preferred embodiments of the invention are described in this application, it is to be clearly understood that the invention is not limited thereto and may be embodied otherwise within the scope of the following claims. Terms such as "preferred," "particular," "particularly," "advantageous," or the like therefore refer only to optional and exemplary embodiments.

Claims

Claims 1. Device (1) for forming a tube head blank (2a) of a tube blank (2) so that a tube blank with a finished tube head (2c) is obtained, comprising - a lower tool (3) with a lower tool body (3a) and an upwardly projecting free end (3b) which has an outer shape which corresponds to a designated inner shape of the finished tube head, over which lower tool the tube blank can be slipped, so that a longitudinal axis (x) of the lower tool and a longitudinal axis of the tube blank are identical and the tube head blank to be formed comes to rest around the free end, - a temperature-controlled upper tool (4) whose longitudinal axis is identical to the longitudinal axis (x) of the lower tool, wherein the upper tool is movable back and forth along the longitudinal axis (x), wherein the lower tool with the tube blank placed thereon can be received in an upper tool body (4a) of the upper tool, wherein the upper tool has an upper head end piece (5) with at least two openable and closable mold jaws (5a), which together form a first recess (6) centered with respect to the longitudinal axis, which recess defines an outer shape of the finished tube head in a closed position of the mold jaws and is diametrically larger in an open position of the mold jaws than in the closed position of the mold jaws, wherein the upper head end piece further comprises an actuating device (5c, 7) for opening and closing the mold jaws, - a tempering system for heating the upper tool to a specified temperature, wherein the upper tool can be lowered onto the lower tool or the lower tool can be raised into the upper tool, such that the tube head blank in the first recess in the open position of the mold jaws comes to rest and can be formed between the closed mold jaws and the free end of the lower tool to form the finished tube head.

2. Device according to claim 1, wherein the tempering system is designed to heat the mold jaws or the entire head end piece of the upper tool or the entire upper tool to a first temperature which corresponds to the intended temperature, at which the tube head blank can be irreversibly formed into the finished tube head by cold forming, wherein the upper tool can be heated either before being lowered onto the lower tool or after being lowered onto the lower tool.

3. Device according to claim 1 or 2, wherein the temperature control system is designed to cool the mold jaws or the entire head end piece of the upper tool or the entire upper tool to a second temperature so that the tube blank with the molded-on finished tube head can be removed from the device in a dimensionally stable manner.

4. Device according to one of the preceding claims, wherein the tempering system is designed to heat the free end of the lower tool or the entire lower tool to a third temperature at which the tube head blank can be irreversibly formed into the finished tube head by cold forming, and / or wherein the tempering system is designed to cool the free end of the lower tool or the entire lower tool to a fourth temperature, so that the tube blank with the formed-on finished tube head can be removed from the device in a dimensionally stable manner.

5. Device according to claim 4, wherein in the case that the tempering system is designed to heat the lower tool in addition to heating the upper tool, the first temperature is higher than the third temperature.

6. Device according to one of the preceding claims, wherein the mold jaws are movable radially to the longitudinal axis (x) for closing and opening, so that the free end of the lower tool with the tube head blank can be enclosed from the side by the mold jaws and that in the open position of the mold jaws the free end of the lower tool with the finished tube head can be released, in particular wherein exactly three mold jaws are provided.

7. Device according to one of the preceding claims, wherein the actuating device comprises a spring system with a plurality of springs (7) which are arranged such that they are relaxed in the open position of the mold jaws and are tensioned in the closed position of the mold jaws such that they press the mold jaws radially outwards.

8. Device according to claim 7, wherein the actuating device further comprises a retaining element (5c) which is movable back and forth in the x-direction and holds the mold jaws in the closed position when the springs are tensioned, wherein the retaining element is a cover (5c) which has a second recess in which the mold jaws can be at least partially received. 9 . Device according to claim 7 and 8, wherein the mold jaws each have an oblique surface (F) on the outside, so that in the closed position of the mold jaws they have the shape of a truncated cone upwards, wherein the retaining element has a corresponding has an inclined counter surface, wherein the counter surfaces in the open position of the mold jaws interact with the inclined surfaces of the mold jaws when the retaining element is lowered in the direction of the mold jaws and slide down thereon with increasing lowering, whereby the mold jaws can be compressed radially towards the longitudinal axis (x) into the closed position and the retaining element can be raised accordingly to open the mold jaws, whereby the springs press the mold jaws radially away from the longitudinal axis (x).

10. Device according to one of the preceding claims, wherein the inner shape of the mold jaws is such that in their closed position a designated external thread can be formed in the external shape of the tube head blank, so that a finished tube head with an external thread is produced.

11. Device according to one of the preceding claims, wherein the mold jaws are interchangeable with alternative mold jaws whose internal shape is different, in particular wherein the number of mold jaws can also vary, in particular wherein the device comprises a set of interchangeable mold jaws which can be selected at least from the following group: mold jaws for tube heads with external thread, mold jaws for tube heads for snap closure, mold jaws for tube heads for impact closure, mold jaws for tube heads for shoulder closure.

12. Device according to one of the preceding claims, wherein the head end piece (5) tapers on the inside starting from the upper tool body (4a) in the direction of the first recess, so that the tube head blank can be inserted into the first recess up to a designated end position with increasing lowering of the upper tool while compressing the tube head blank. 13 . Device according to one of the preceding claims, further comprising a first drive for displacing the upper tool and / or the lower tool translationally back and forth along the longitudinal axis (x), in particular wherein the first drive is not designed for a rotational movement of the upper tool and / or the lower tool about the longitudinal axis (x), and / or further comprising a second drive for displacing the retaining element translationally back and forth along the longitudinal axis (x).

14. Device according to one of the preceding claims, wherein a valve, a compressed air line connected to the valve, in particular running inside the lower tool body, and a compressed air compressor arranged outside the lower tool are provided in the lower tool body or in the free end of the lower tool, wherein the valve is closed during the forming of the tube head blank and can be opened after the forming by means of compressed air led from the compressed air compressor through the compressed air line, so that the compressed air can flow between the lower tool and the turned-up tube blank with finished tube head and thus causes the tube blank to be detached from the lower tool, in particular wherein the valve is aligned such that the outflow direction of the compressed air from the valve not only supports the detachment of the tube blank but also the lifting of the tube blank from the lower tool.

15. Method for forming a tube head blank of a tube blank by means of a device according to one of the preceding claims, comprising the steps: a) Slipping the tube blank with the tube head blank over the lower tool so that the tube head blank comes to rest around the free end of the lower tool and the tube body lies against the lower tool body, b) Lowering the upper tool with open mold jaws onto the lower tool equipped with the tube blank up to a first position in which the tube head blank comes to rest in the first recess, c) Closing the mold jaws, and d) Further lowering of the upper tool up to an end position in which the forming of the tube head is carried out, whereby the upper tool is heated to a specified temperature.

16. Method according to claim 15, wherein after the forming of the tube head, the tube blank is released from the lower tool by blowing compressed air between the lower tool and the turned-up tube blank with finished tube head, thus assisting the detachment of the tube blank from the lower tool.

17. Method according to claim 16, wherein the compressed air is cooled by means of the temperature control system before it is blown between the lower tool and the fitted tube blank.

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