Thermoforming tool, thermoforming station, device for producing thermoformed mouldings and method for producing thermoformed mouldings

Abstract

The invention relates to a thermoforming tool (1, 2) for thermoforming a film (5, 6) from a thermoplastic material into a molded part (6, 7), in particular a molded part (6, 7) of a refrigerator, the thermoforming tool (1, 2) comprising an upper tool part, a lower tool part (11) and a holding device (12, 13) for holding the film (5, 6) between the two tool parts (10), wherein the thermoforming tool (1, 2) is characterized by a measuring device (25A, 25, 26) for measuring at least one wall strength (26) on the thermoformed film (5).

Description

[0001] The invention relates to a thermoforming tool for thermoforming a film of thermoplastic material into a molded product, in particular a molded product for a refrigerator. The thermoforming mold has an upper tool part, a lower tool part and a holding device for holding the film between the two tool parts.

[0002] The invention further relates to a thermoforming station for producing thermoformed mouldings from a film, the thermoforming station having a thermoforming tool for thermoforming the film and having a feed section for feeding the thermoforming tool.

[0003] The invention also relates to a system for producing thermoformed moldings from films.

[0004] The present invention also relates to a method for producing thermoformed moldings, in particular thermoformed moldings for refrigerators, from a film of thermoplastic material, wherein the film is held by a holding device on a thermoforming tool and simultaneously formed into a thermoformed molding by means of the thermoforming tool.

[0005] It is known from the prior art to shape thermoplastically deformable films into mouldings, also into larger mouldings, such as, in particular, refrigerator inserts or the like, by means of suitable thermoforming tools.

[0006] For example, a thermoforming tool for forming a molded article from a thermoplastic material is known from WO 2014 / 187446 A2, wherein the thermoplastic material is provided as a film web, in particular a plastic sheet. The molded article may be a thermoformed product in the form of a semi-finished product for a refrigerator.

[0007] The invention is based on the task of further developing previously known thermoforming possibilities. In particular, the invention is based on the task of further developing universal thermoforming tools and thermoforming processes in order to make the production of thermoformed moldings more efficient.

[0008] The object of the present invention is achieved by a thermoforming tool for thermoforming a film of thermoplastic material into a molded product, in particular a molded product for a refrigerator, the thermoforming tool having an upper tool part, a lower tool part and a holding device for holding the film between the two tool parts, the thermoforming tool being characterized by a measuring device for measuring at least one wall thickness of the thermoformed film.

[0009] There is an increasing demand for the production of thermoformed parts with thinner walls, such as refrigerator interiors, etc. In this case, however, the wall thickness must not fall below a critical value in order to ensure a minimum degree of dimensional stability, durability, etc. of the molded part with optimum material savings.

[0010] Particularly in the case of mouldings which are to be refoamed later, care must be taken to ensure that the wall thickness is always selected in such a way as to exclude the risk of the foam layer being inadvertently squeezed through the moulding wall during foaming. Such applications exist, for example, in refrigerator interiors.

[0011] If a measuring device is provided on the thermoforming mold, by means of which one or more wall thicknesses of the already thermoformed film can be measured, an initial quality check can be carried out immediately after the forming process to determine whether the molded article just produced meets the customer's quality requirements.

[0012] In other words, after the thermoforming of the film, the just produced moulding (whether semi-finished product or finished product) can be checked immediately on or in the thermoforming mould to see whether it is a good part or a bad part.

[0013] In the case of a bad part, the minimum wall thickness has been reached or not reached at least at one point in the molding.

[0014] In this case, the thermoformed part is still located in the thermoforming mold, so that the quality of the final, already thermoformed product (semi-finished product or finished product) can be determined earlier than was previously possible.

[0015] It is also particularly advantageous here that the freshly formed molded part is still clamped in a defined manner on the thermoforming tool for the thickness measurement provided within the scope of the invention, which means that the thickness measurement can be carried out particularly quickly and precisely on the thermoforming tool. This means that the quality inspection function can be integrated extremely precisely into the thermoforming tool at hand.

[0016] The thermoforming tool can be designed in a variety of ways, as long as it can be used in a thermoforming process for films to produce thermoformed moldings or parts of correspondingly high quality.

[0017] The thermoforming mould has at least two tool parts, which are arranged to be movable towards each other so as to be able to close the thermoforming mould. For this purpose, at least one of the mould parts is arranged to be movable relative to the other mould part.

[0018] Typically, the film is fed to the thermoforming mold along a feed path that extends between two mold parts.

[0019] Preferably, the upper mould part comprises as first mould part a suction pressure bell, by means of which the film can, if required, be additionally pressed against the mould of the thermoforming mould by means of overpressure or compressed air.

[0020] With the aid of such a suction pressure bell, it is also possible to draw the film into the suction pressure bell by means of an additional suction action, in particular before the actual pressure forming of the film, in order to allow preforming of the film.

[0021] The lower mould part, which is a complementary second mould part, preferably comprises a male mould part, onto which the film is placed during thermoforming, so that the film can be formed into the desired moulding.

[0022] In the present case, the individual mould parts play only a minor role, if any, in the selected orientation within the thermoforming mould. Thus, the lower mould part may also comprise a suction pressure bell-shaped part and the upper mould part may comprise a male mould part.

[0023] Furthermore, the term "holding device" in the context of the present invention describes a device by means of which the film is reliably held between the mold parts of the thermoforming mold. The holding device can be implemented in a variety of ways, for example as a clamping frame part. Cumulatively or alternatively, a plurality of separate grippers can also be provided for holding the film. Clamping frame parts and separate grippers are already known from the prior art.

[0024] For example, the measuring device can be arranged on a holding device. However, other support frames or bridge frames can also be provided to hold the measuring device.

[0025] The term "film" describes a foil-like semi-finished product, which can be either a thin foil or a thicker sheet with a thickness of 1.5 mm or more. Preferably, the sheet is thermoformed to produce, for example, refrigerator interiors or the like.

[0026] Especially in the case of larger mouldings, such as refrigerator interiors etc., very high moulding forces of, for example, 800 kN or more may occur.

[0027] The term "molding" describes a preferably three-dimensional part which is thermoformed from a previously essentially two-dimensional film or sheet. The molding can be in the form of a semi-finished product (eg a refrigerator inner shell still to be foamed) or in the form of a finished product.

[0028] It should also be noted that in the context of this patent application, indefinite articles and indefinite numerals such as "one...", "two...", etc. should generally be understood as minimum indications, i.e., "at least one...", "at least two...", etc., unless it is clear from the context or the specific text of a particular paragraph that it is intended only to indicate "exactly one...", "exactly two...", etc.

[0029] At this point it should be mentioned that in the context of the present patent application the expression "in particular" is always to be understood in such a way that optional, preferred features are introduced by means of this expression. This expression is not to be understood in the sense of "namely".

[0030] Preferred embodiments provide that the measuring device comprises a measuring sensor component, in particular a mechanical measuring sensor component, an optical measuring sensor component, an acoustic measuring sensor component, etc. Advantageously, the measuring device can be designed in such a way that it is able to perform various measuring methods, only some of which are mentioned here as examples, individually or in combination.

[0031] In particular, within the scope of the invention, such a measuring sensor component is also a separate component of the measuring device. In addition, the additional components can include, for example, an evaluation unit, such as a computer-based calculation unit, a drive unit or the like.

[0032] For example, a mechanically operated measuring sensor component may be provided which has a very robust construction and therefore requires very little maintenance.

[0033] Additionally or alternatively, optically operated measuring sensor components can also be provided, which can advantageously be operated contactlessly.

[0034] Likewise cumulatively or alternatively, acoustically operating measuring sensor components may be considered, which may also be operated contactlessly.

[0035] Advantageously, optically and acoustically operating measuring sensor components can also be arranged at a distance from the mold components of the hot forming mold. For example, such measuring sensor components can thus be maintained or cleaned with less risk.

[0036] The measuring device can be mounted on the thermoforming mold in different ways. For example, the measuring device or at least its individual components are arranged on a holding device. This allows the measuring device to be held very compactly on the thermoforming mold.

[0037] Furthermore, if the holding device is embodied in a movable manner on the thermoforming tool, for example on a holding frame for holding films or the like, the measuring device can advantageously be spatially displaced by means of the holding device, in particular relative to the lower tool part or the molded product.

[0038] It should be understood that the measuring device may also be attached to the thermoforming mould in other ways. For example, the measuring device may be arranged on one of the mould parts of the thermoforming mould.

[0039] Alternatively, a separate support frame can be provided on the thermoforming mould to carry the measuring device, but this increases the construction effort.

[0040] Furthermore, it is advantageous if the measuring device or at least individual parts thereof are arranged in front of the outside of the lower mould part, in particular next to the side of the lower mould part, so that the measuring device can detect the position of the side outside of the lower mould part and subsequently the matching position of the outside of the moulding.

[0041] It is particularly advantageous if the measuring device or at least individual parts thereof are arranged in front of a wall region of a mold part in which the direction of the wall changes, since this also allows measurements to be taken at particularly critical regions of the wall thickness of the molded article.

[0042] Particularly at curves, corners, edges, shoulders etc., very thin material areas often occur on the walls of the moldings due to material optimization for the moldings (e.g. interior refrigerator parts) etc. In principle, it is therefore particularly desirable to measure the existing wall thickness of the moldings at such wall areas.

[0043] Therefore, the wall thickness is preferably measured at critical wall areas of the thermoformed molded article. Such critical wall areas are located, for example, at or near curves, corners, etc. of the molded article, which generally coincide with corresponding curves, corners, edges, shoulders, etc. of mold parts, especially the lower mold part, of the thermoforming mold.

[0044] In this respect, a preferred embodiment provides that the measuring device or at least individual parts thereof are arranged at a working region of the thermoforming mold, in which the lower mold part and the molded product can be arranged congruently, whereby the thickness measurement effort can generally be greatly reduced. At least, the lower mold part and the molded product can be positioned congruently in this working region.

[0045] A very simple embodiment provides that the measuring device or at least individual parts thereof are arranged in front of the lower mold part both when the thermoforming mold is closed and when it is open.

[0046] For example, when setting up the thermoforming tool, the measuring sensor components of the measuring device are positioned and aligned once so that they are essentially always mounted stationary in front of the working area for the wall thickness measurement.

[0047] Thus, with suitable embodiments of the invention, the measuring device may be permanently placed in the measuring area.

[0048] Such a measuring area is characterized, inter alia, by the fact that it is located in or on the working area of ​​the thermoforming device (thermoforming mold, thermoforming station, etc.), in particular next to the working area, in which at least one mold part wall and one molded product wall can be arranged congruently side by side.

[0049] Alternatively, the measuring device or at least individual parts thereof can also be arranged movably on the thermoforming mold so that the measuring device can be moved from a measuring or working position to a waiting position, for example for closing the thermoforming mold, ie during the actual thermoforming process.

[0050] It should be borne in mind here that the measuring device or at least individual parts thereof can be mounted on the thermoforming mold in such a way that they can be moved, pivoted, folded or the like.

[0051] In this respect, it is advantageous if the measuring devices or at least individual parts thereof are arranged such that they can be displaced relative to the mold part walls and / or relative to the molded product walls.

[0052] This allows, for example, the use of separate measuring sensor components at different measuring points. For this purpose, the corresponding components of the measuring device can be moved along a curved path or the like.

[0053] A displacement of the measuring device or at least of its individual parts parallel to the plane of the mold part walls and / or the molded product wall may also be advantageous here in order to enable the most compact possible access to the individual measuring regions on a single plane.

[0054] Furthermore, it is advantageous if the measuring device or at least individual parts thereof can be arranged in the measuring region between the two mold parts, so that preferably all relevant wall surfaces of the lower mold part and the molding formed thereon can be reached by the measuring device.

[0055] It therefore does not matter whether the surfaces of the mold parts or the molded article formed thereon are aligned vertically or horizontally.

[0056] Furthermore, by at least temporarily arranging the measuring device or at least individual parts thereof, the position of in particular a mold part wall can also be mechanically sensed, so that a mechanical wall thickness measurement can be performed immediately on or in the thermoforming mold.

[0057] It is therefore advantageous if the measuring device is arranged on the thermoforming mould so that it can be inserted between the mould parts of the thermoforming mould.

[0058] Furthermore, it is advantageous if the measuring device or at least individual parts thereof have a linear drive. With the aid of such a linear drive, the measuring sensor part can be moved orthogonally in a more targeted manner toward the mold part wall and / or the molded product wall. In particular with mechanically operated measuring sensor parts, such a linear drive is preferably used, for example, to move the probe element upwards toward the mold part wall and / or the molded product wall.

[0059] In order to be able to carry out a particularly reliable and precise measurement of the wall thickness, a calibration device for calibrating the measuring device, in particular the measuring sensor component, is also advantageous.

[0060] Such a calibration device can be realized in most different configurations, in particular computer-assisted.

[0061] A particularly simple embodiment provides that the measuring device comprises a calibration device, whereby a self-calibrating measuring device can preferably be provided on the hot forming tool.

[0062] The problem of the invention is also solved by a thermoforming station for producing thermoformed molded articles from a film, the thermoforming station having a thermoforming mold for thermoforming the film and having a feed path for feeding the film to the thermoforming mold, the thermoforming station being characterized by a thermoforming mold according to one of the features described herein.

[0063] If a thermoforming station is equipped with a thermoforming tool as described here, a thermoforming station equipped in this way can advantageously carry out a wall thickness measurement of the freshly formed molding immediately, ie even before the molding leaves the thermoforming station.

[0064] This means that a further testing station which was previously required for testing the produced mouldings becomes superfluous or can at least be simplified, since the quality testing function is advantageously already integrated in the hot forming station.

[0065] As a result, the entire manufacturing process of the molded article can be made more efficient.

[0066] The object of the present invention is also achieved by an alternative thermoforming station, which is used to produce thermoformed molded articles from a film with the aid of a thermoforming tool for thermoforming the film and a feed section for feeding the thermoforming tool, and is characterized by a measuring device for measuring at least one wall thickness of the thermoformed film according to one of the characteristics described herein.

[0067] Advantageously, by means of this improved thermoforming station, conventional thermoforming molds can be additionally used according to the invention, so that the manufacturing process of the molded article can be carried out more efficiently.

[0068] Not only in this context, it is advantageous if the thermoforming station has a positioning device, on which the measuring device or at least a separate part thereof is arranged, which is different from the thermoforming mold.

[0069] This means that the measuring device required for the thickness measurement of the wall thickness on the thermoforming film can also be arranged at the thermoforming station independently of the thermoforming tool without any problems.

[0070] In other words, this also means that the measuring device can be arranged outside the hot forming tool.

[0071] The positioning device may be provided as a simple frame part suitable for supporting the measuring device.

[0072] In a further developed positioning device, additional means can be provided for displacing or moving the measuring device or at least individual parts thereof, whereby the measuring device can be arranged at least temporarily on or in the hot forming mold.

[0073] The object of the invention is also achieved by a device for producing thermoformed moldings from films by means of at least one production line, wherein the device comprises a thermoforming tool or a thermoforming station having one of the features described herein.

[0074] With the aid of an apparatus equipped in this way, thermoformed moldings can be produced substantially more efficiently than before, since the thermoforming of the film and at least a first test in the form of a thickness measurement of the wall thickness of the thermoformed molding can be carried out in a single clamping process of the film or molding.

[0075] At this point it should be explicitly pointed out that this significant advantage also applies to the thermoforming mould or thermoforming station described here.

[0076] The system is preferably equipped with a film holding station, which can be realized, for example, by an unwinding station.

[0077] Furthermore, if it is convenient to provide a heating station, the heating station is placed before the thermoforming station on the production line.

[0078] It should be understood that the production line may also include other work stations.

[0079] The object of the present invention is also solved by a method for producing thermoformed molded articles, in particular thermoformed molded articles for refrigerators, from a film made of thermoplastic material, wherein the film is held on a thermoforming mold by a holding device, and while the film is being formed into a thermoformed molded article with the aid of the thermoforming mold, a thickness measurement of at least one wall thickness of the thermoformed molded article is performed on the thermoforming mold.

[0080] By measuring the wall thickness of a film, or more precisely of an already thermoformed molding, while the molding still remains on or in the thermoforming mold, the method for producing moldings from thermoplastic materials can be significantly simplified.

[0081] In particular, the thickness measurement can be carried out in the same film setup in which the film is already held by the holding device during the actual thermoforming process.

[0082] This means that the thermoforming method is not only very efficient because no subsequent re-clamping of the thermoformed part is required, but also very precise due to the single clamping.

[0083] In this respect, a preferred process variant provides that the thickness measurement of the thermoformed molding is carried out while the film is held on the thermoforming tool by means of a holding device, in particular in the initial film clamping of the film on the thermoforming tool.

[0084] Therefore, a particularly advantageous method variant provides that the hot forming of the film into the molding and the subsequent at least one thickness measurement of the wall thickness of the molding are carried out in the same film clamping process.

[0085] It is also very advantageous if the thickness measurement is performed after each thermoforming process but before the thermoformed molded product is ejected from the thermoforming mold. In this way, it can be ensured that the thickness measurement of the wall thickness is performed on each molded product produced before the molded product leaves the thermoforming mold or the thermoforming station.

[0086] If the thickness measurement is performed after the thermoformed moulding has cooled, it can be ensured that the shrinkage effect of the film after cooling can also be taken into account when measuring the thickness at or in the thermoforming mould.

[0087] As mentioned above, different measurement methods can be used to perform thickness measurement, for example by means of non-contact, or alternatively contact measurement methods.

[0088] For a further development of the method, a particularly robust and therefore also reliable measuring method provides that, for the thickness measurement, a measuring sensor part of the measuring device, in particular a probe element, is moved upwards to the mold part wall surface by contact (calibration) in a first step, the measuring sensor part is retracted again in a second step and then, after the actual thermoforming process of the film to form the molded article, the measuring sensor part is moved upwards to the molded article wall surface in a third step by contact (comparison measurement) in correspondence with the mold part wall surface.

[0089] Here, the mold part wall surface forms the reference surface of the measuring device. In this respect, the corresponding mold part can also be regarded as a part of the measuring device.

[0090] Preferably, as already explained above, the displacement of the measuring sensor component or the probe element takes place by means of a linear motor.

[0091] In this respect, the measuring device is calibrated to the thermoforming mold, in particular to a mold part of the thermoforming mold, more precisely to a mold part surface, so that the thickness of the molded article is subsequently measured according to this calibration.

[0092] The method can advantageously be carried out in a single separate thermoforming station for producing thermoformed mouldings and, alternatively, in an apparatus for producing thermoformed mouldings having at least one production line comprising a thermoforming station.

[0093] At this point it should also be stated that the described method can also be supplemented by further technical features described herein in order to advantageously further develop the method.

[0094] It will be understood that, if necessary, features of the above-described solutions or features in the claims may also be combined so that the advantages and achievable effects herein can be implemented in a corresponding cumulative manner.

[0095] Further features, effects and advantages of the invention are explained with reference to the drawings and the following description, in which a first embodiment of the invention is shown and described by way of example.

[0096] The attached figure is shown below:

[0097] Figure 1 An exemplary model view of a thermoforming station for thermoforming a film from a thermoplastic material into a molded article is schematically shown, which has a measuring device for measuring at least one wall thickness of the thermoformed film.

[0098] Figure 2 Schematically shows Figure 1 Perspective view of the lower mold component of the thermoforming station.

[0099] Figure 3 Schematically shows Figure 1 and Figure 2 Detailed view of the mechanically operated measuring sensor component of the measuring device of the hot forming station in the basic or waiting position;

[0100] Figure 4 Schematic diagram showing the calibration position Figure 3 A more detailed view of the measuring sensor components shown in detail in FIG. 1 ; and

[0101] Figure 5 A cross section of a thermoformed molding in the form of a refrigerator interior component shell combined with a lower mold part is schematically shown.

[0102] Figures 1 to 4 A possible embodiment of a thermoforming mold 1 in a thermoforming station 2 is shown, according to which the thermoforming station 2 is integrated in an apparatus 3 for producing thermoformed moldings 6 made of a film 5 (see Figure 5 ), where the molded product 6 is a refrigerator internal component housing 7. Therefore, the film 5 in this embodiment is configured as a sheet (not shown) having a sufficient material thickness.

[0103] The thermoforming mould 1 substantially comprises an upper mould part 10 , a lower mould part 11 and a holding device 12 for holding the film 5 between the two mould parts 10 and 11 .

[0104] The upper mold part 10 includes a suction pressure bell-shaped part of the thermoforming mold 1 (again not marked here), and the lower mold part 11 includes a male mold part (again not marked), and the film 5 is formed on the male mold part during thermoforming so as to give the two-dimensional film 5 the desired shape such as the three-dimensional molded product 6.

[0105] The holding device 12 shown at least partially here is part of a clamping frame (not explicitly indicated here) of the thermoforming mold 1, with the help of which the film 5 to be formed is clamped in the thermoforming mold 1 and therefore also in the thermoforming station 2 on a horizontal holding or clamping plane 13.

[0106] The film 5 is fed to the thermoforming mould 1 along a feed path 15 of the thermoforming station 2 , which in the exemplary embodiment shown here is located in a production line 16 of the system 3 .

[0107] exist Figure 1 In FIG. 1 , a thermoforming station 2 is shown with a closed thermoforming mold 1 , wherein a horizontal holding or clamping plane 13 is located between two molded articles 10 and 11 at a feed path 15 .

[0108] The thermoforming station 2 has a frame 20 with a lower part 21 for accommodating the lower mold part 11 and with an upper part 22 for accommodating the upper mold part 10. The frame 20 also includes a punch guide part 23 (only as an example number), by which the upper part 22 and the lower part 21 can be locked to the frame 20, in particular during thermoforming or compressed air forming.

[0109] The thermoforming mould 1 also features a measuring device 25 for measuring at least one wall thickness 26 of the thermoformed film 5, more precisely of the thermoformed moulding 6 or of the thermoformed refrigerator interior housing 7 (see Figure 5 ).

[0110] In this embodiment, the measuring device 25 comprises, on the one hand, a bridge part 27 as a support frame for the measuring device 25 , which bridge part 27 is supported by the holding device 12 or a corresponding clamping frame.

[0111] As can be clearly seen, especially in Figure 2 In the illustration, the measuring device 25 also has a large number of measuring sensor components 28 (indicated here only as an example), so that preferably several thickness measurements of the wall thickness 26 can be carried out simultaneously at different measuring points 29 or measuring areas on the molded product 6.

[0112] In this respect, the measuring device 25 or at least its individual components (bridge element 27 , a plurality of measuring sensor elements 28 , etc.) are arranged on the holding device 12 or on the clamping frame.

[0113] Alternatively—according to a corresponding design of the invention—the individual measuring sensor components 28 of the measuring device 25 can be fixed directly to the holding device 12 or to a clamping frame (not shown here), ie without interposing bridge elements 27 or the like.

[0114] The measuring sensor element 28 used here is a mechanical measuring sensor element 30 which is arranged fixedly on the bridge element 27 or the holding device 12, but can be actively contacted by means of a detection element 31 on the one hand with a mold part wall area 32 (only exemplary numbering) for calibrating the measuring device 25, and on the other hand subsequently with a molded product wall area 33 (see Figure 5 ) Active contact is used for actual thickness measurement.

[0115] The hot forming tool 1 or the hot forming station 2 therefore has a calibration device (again not shown) directly, namely in the form of a self-calibrating measuring device 25 .

[0116] Here, the mold part wall region 32 serves as a reference plane, which can preferably be designed as a vertical reference plane 35 (only as an example number) and / or as a horizontal reference plane 36 (only as an example number).

[0117] In this respect, in particular the mold part wall region 32 and the reference surfaces 35 and / or 36 are components belonging to the measuring device 25 .

[0118] Here, the individual measuring sensor part 28 is movably mounted on the bridge part 27 along a slide path 41 by means of a retaining rail 40 so that the individual measuring sensor part 28 is movably mounted, in particular depending on the shape of the lower mold part 11 or the molded product 6 to be thermoformed.

[0119] In the exemplary embodiment shown here, the separate measuring-sensor part 28 is therefore mounted movably in or along a vertical plane 42 which extends substantially plane-parallel to the vertical reference plane 35 of the lower mold part 11 and the molded product 6 .

[0120] In this respect, the separate measuring sensor component 28 can also be close to the wall region 32 of the lower molded part 11 at or near which the wall 43 of the lower molded part 11 changes direction, for example in the form of a curve, edge, projection, depression or the like.

[0121] In such wall regions 32 , critical wall thicknesses 26 often occur on the moulding 6 , which are to be checked metrologically in order to be able to distinguish bad parts from good parts at an early stage.

[0122] Furthermore, each mechanical measuring sensor part 30 has a housing 45 which accommodates a linear motor 46. The linear motor 46 has a guide rail 47 by means of which the detection element 31 can be moved substantially perpendicularly to the respectively associated mold part wall region 32 or molded product wall region 33.

[0123] Figure 5 An example of how a molded article 6 is formed on the lower mold part 11 is shown, with the film 5 or the molded article 6 still being held by the holding device 12 , while a thickness measurement is carried out or completed by means of a measuring device 25 .

[0124] For this purpose, the measuring device 25 or at least its individual components 27 , 28 , 30 , 31 , 40 , 41 , 45 , 46 , 47 can be arranged at least temporarily in a working area 50 of the thermoforming mold 1 , in which the lower mold part 11 and the molded product can be arranged congruently.

[0125] In the same way, the measuring device 25 or at least its individual parts 27, 28, 30, 31, 40, 41, 45, 46, 47 can be arranged at least temporarily upwards to the measuring area 51 between the two mold parts 10 and 11 in order to carry out thickness measurement according to the invention.

[0126] At this point it should also be mentioned that in another differently constructed embodiment, the individual measuring sensor components (not shown here) of the measuring device 25A can also be arranged cumulatively or alternatively independently of the hot forming mold 1 in another positioning device 55 (as shown by the dashed line, see Figure 1 ), whereas in the exemplary embodiment shown here the measuring device 25 is assigned directly to the hot forming mold 1 .

[0127] In terms of process technology, for example, a method for producing a thermoformed molded product 6, in particular a thermoformed refrigerator interior component shell 7 for a refrigerator, from a thermoplastic film 5 can be used, in particular with the aid of the thermoforming mold 1 introduced herein or the thermoforming station introduced herein, to measure the thickness of the wall thickness 26 of the thermoformed molded product 6, wherein the film 5 is held or clamped on the thermoforming mold 1 by a holding device 12, and at the same time, the film 5 is formed into the thermoformed molded product 6 or the refrigerator interior component shell 7 with the aid of the thermoforming mold 1, wherein the thickness measurement of at least one wall thickness 26 of the thermoformed molded product 6 or 7 is performed directly at the thermoforming mold 1 or in the thermoforming mold 1.

[0128] In other words, this means that the thickness measurement is carried out while the film 5 or the molding 6 is still held by the holding device 12 .

[0129] At this point it should be explicitly pointed out that, if necessary, features of the solutions described above or features in the claims and / or drawings may also be combined in order to implement or achieve the explained features, effects and advantages in a corresponding cumulative manner.

[0130] It should be understood that the exemplary embodiment explained above is only the first embodiment of the device for measuring the wall thickness of a film, sheet or molded article of thermoplastic material just thermoformed according to the present invention. Therefore, the present invention is not limited to this embodiment.

[0131] All features disclosed in the application documents are considered essential to the invention insofar as they are new alone or in combination with one another compared with the prior art.

[0132] Reference numerals list

[0133] 1 Thermoforming mold

[0134] 2 Thermoforming stations

[0135] 3 Equipment

[0136] 5 films

[0137] 6 Molding

[0138] 7 Refrigerator internal parts housing

[0139] 10 Upper mold part

[0140] 11 Lower mold part

[0141] 12. Holding device

[0142] 13 Holding or clamping flat surface

[0143] 15 Feeding Line

[0144] 16 Production Lines

[0145] 20 Framework

[0146] 21 Lower part

[0147] 22 Upper part

[0148] 23 Punch guide component

[0149] 25. Measuring device

[0150] 25A Additional measuring device

[0151] 26 Wall thickness

[0152] 27 Bridge components

[0153] 28 Measuring sensor components

[0154] 29 measuring points

[0155] 30 Mechanical measurement sensor components

[0156] 31 Detection element

[0157] 32 Mold component wall area

[0158] 33 Molding wall area

[0159] 35 Vertical reference plane

[0160] 36 Horizontal reference plane

[0161] 40 Keep the slide rails

[0162] 41 Slide Path

[0163] 42 Vertical plane

[0164] 43 wall

[0165] 45 Shell

[0166] 46 Linear Motor

[0167] 47 Slide Rail

[0168] 50 working area

[0169] 51 Measurement area

[0170] 55 Positioning device

Claims

1. A thermoforming mould (1) for thermoforming a film (5) of a thermoplastic material into a moulding (6), comprising an upper mould part (10), a lower mould part (11) and a holding device (12) for holding the film (5) between the two mould parts, a measuring device (25) for measuring at least one wall thickness (26) of the thermoformed film (5), It is characterized in that The measuring device (25) or at least individual parts thereof are arranged on a holding device (12), wherein: - the retaining device (12) is a clamping frame part; and / or The holding device (12) comprises a plurality of individual grippers for holding the film.

2. The thermoforming mold (1) according to claim 1, It is characterized in that The measuring device (25) comprises a measuring sensor component (28).

3. The thermoforming mold (1) according to claim 2, It is characterized in that The measuring device (25) comprises a mechanical measuring sensor component (30), an optical measuring sensor component or an acoustic measuring sensor component.

4. The thermoforming mold (1) according to claim 1 or 2, It is characterized in that The measuring device (25) or at least individual parts thereof are arranged on the outer front side of the lower mould part (11).

5. The thermoforming mold (1) according to claim 1 or 2, It is characterized in that The measuring device (25) or at least individual parts thereof are arranged laterally next to the lower tool part (11).

6. The thermoforming mold (1) according to claim 1 or 2, It is characterized in that The measuring device (25), or at least individual parts thereof, is arranged in front of a wall region of the wall (43) of the mold part in which the direction changes.

7. The thermoforming mold (1) according to claim 1 or 2, It is characterized in that The measuring device (25) or at least individual parts thereof is arranged in a working area (50) of the thermoforming mold (1), and is capable of arranging the lower mold part (11) and the molded product (6) in the working area (50) in a corresponding manner.

8. The thermoforming mold (1) according to claim 1 or 2, It is characterized in that The measuring device (25) or at least individual parts thereof are arranged in front of the lower mould part (11) when the thermoforming mould (1) is closed and opened.

9. The thermoforming mold (1) according to claim 1 or 2, It is characterized in that The measuring device ( 25 ) or at least individual parts thereof can be arranged upwardly in the measuring region ( 51 ) between the two mold parts.

10. The thermoforming mold (1) according to claim 1 or 2, It is characterized in that The measuring device (25) or at least individual parts thereof have a linear drive.

11. The thermoforming mold (1) according to claim 1 or 2, It is characterized in that The molded product (6) is a molded product of a refrigerator.

12. A thermoforming station (2) for producing thermoformed moulded articles (6) from a film, comprising a thermoforming mould (1) for thermoforming the film (5) and a feed path (15) for feeding the film (5) to the thermoforming mould (1), It is characterized in that The thermoforming mould (1) according to any one of claims 1 to 10.

13. A plant (3) for producing thermoformed moldings from films (5) having at least one production line (16), It is characterized in that The device (3) comprises a hot forming mold (1) according to any one of claims 1 to 11 or a hot forming station (2) according to claim 12.

14. A method for producing a thermoformed molded article (6) from a film (5) made of a thermoplastic material, wherein the film (5) is held on a thermoforming mold (1) according to any one of claims 1 to 11 by a holding device (12), and the film (5) is simultaneously formed into the thermoformed mold (6) by the thermoforming mold (1), It is characterized in that At least one wall thickness (26) of the thermoformed molding (6) is measured at the thermoforming mold (1).

15. The method according to claim 14, It is characterized in that When the film (5) is held on the thermoforming mold (1) by the holding device (12), the thickness of the thermoformed molded product (6) is measured.

16. The method according to claim 14 or 15, It is characterized in that Thickness measurements are performed after each thermoforming process but before the thermoformed molding (6) is ejected from the thermoforming mold (1).

17. The method according to claim 14 or 15, It is characterized in that The thickness measurement is carried out after the thermoformed molding (6) has cooled.

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