Device and method for producing moulded parts

Abstract

The invention relates to a device for producing moulded parts (1), in particular from fibre-composite material. According to the invention, in order to provide uniform application of pressure and / or temperature even in moulded parts having more complex geometry, the second compressing portion (P2, P2') is at least partially spaced apart from the first compressing portion (2) in the direction of the movement axis (B), and at least one bent region of the mould of the second compressing portion (P2, P2'), in particular along the longitudinal extent and / or the transverse extent of the corresponding compression mould (2, 3), is designed to at least partially differ from at least one bent region of the mould of the first compressing portion (P1, P1'), preferably to differ from the bent region of the mould of the edge region, adjoining the second compressing portion (P2, P2'), of the first compressing portion (P1, P1'). The invention also relates to a method for producing moulded parts, in particular from fibre-composite material, comprising, inter alia, a corresponding device for producing moulded parts (1), in particular from fibre-composite material.

Description

[0001]December 22, 2023. Device and method for producing molded parts. The invention relates to a device for producing molded parts, in particular from fiber composite material, comprising: a first pressing tool, a second pressing tool, and at least one at least partially elastically deformable membrane for contacting a workpiece. The first pressing tool and the second pressing tool are movable relative to one another between an open position and a closed position along a movement axis. A cavity for a working medium is formed between the membrane and the first pressing tool and / or the second pressing tool, at least in the closed position. A working space for receiving the workpiece is formed between the first pressing tool and the second pressing tool.wherein the surface of the first pressing tool and / or the surface of the second pressing tool has a first pressing section and a second pressing section, wherein the first pressing section and the second pressing section adjoin the working space and / or the cavity, and wherein the membrane is made of metal. The invention further relates to a method for producing molded parts, in particular from fiber composite material, comprising the following steps: a) providing a workpiece, b) providing a device for producing molded parts according to one of claims 1 to 14, and c) applying pressure and / or temperature to the workpiece by means of the device for producing molded parts. Fiber composite materials are composite materials that essentially consist of two main components: reinforcing fibers and a plastic,in which the fibers are embedded ("matrix" or "resin"). By combining the two main components, the composite material can exhibit better overall properties than either component would have if considered individually. For example, the fibers contribute to increasing the tensile strength of the composite material due to their high tensile strength in the fiber direction. The matrix, on the other hand, ensures that the fibers are held in position and protected from mechanical and chemical influences. One of several options for producing molded parts from fiber composites is based on the use of prefabricated fiber-resin semi-finished products (so-called "prepregs", short for "preimpregnated fibers"). In such semi-finished products, the fibers are provided with a resin system that has not yet fully reacted, so that the semi-finished products are still in a flexible form (e.g., web-like,on rolls). Only during the production of the molded parts are the prepregs formed and cured at high pressure and high temperatures by completing the chemical reaction. This step can be carried out in a press, for example. Prepregs are processed in large quantities in the aviation industry. One challenge in processing is that the aviation industry often requires very complex molded part geometries, for example due to reinforcement elements such as stringers. In addition, the assembly effort should be reduced, which can be achieved by using fewer,but larger molded parts. The combination of complex geometries and large molded part dimensions places increased demands on devices and methods for producing these molded parts. A device and method for producing molded parts from fiber composite material are known, for example, from DE 102017113595 A1. Uniform pressure is applied to the molded part to be produced by an elastic membrane acting on the workpiece from which the molded part is formed, with oil pressure acting on the membrane from the side of the membrane facing away from the workpiece. The membrane is thus pressed onto the workpiece surface by oil pressure and thereby absorbs the G / TG 220975WODecember 22, 2023 shape of the workpiece. In this way, even with curved workpiece surfaces or molded part surfaces, it should be ensured that the oil pressure acts on all sides and thus the force acting from the membrane on the workpiece surface is the same at every point, in particular the force component acting orthogonally on the workpiece surface. A disadvantage here, however, is that the curvature of the mold is constant across the surface of the pressing tools. Molded parts with complex geometries, in particular with changing curvatures and / or opposing curvatures, cannot be produced with such a device, or can only be produced with great difficulty. The use of such a "membrane press" for the production of molded parts made of fiber composite material is also known from US 2016 / 0297153 A1. A disadvantage here, however, is that contact with the workpiece orOnly a rigid wall is provided for the molded part. Although the rigid wall can be connected to a flexible membrane, the flexible membrane is not intended for contact with the workpiece. Particularly in areas of the workpiece or molded part to be produced with less complex geometries, such a rigid wall cannot adapt to the geometry of the workpiece or molded part through elastic deformation, or cannot adapt sufficiently, and thus cannot enable uniform application of pressure and / or temperature. The invention is therefore based on the object of providing a device and a method for producing molded parts, in particular from fiber composite material, which ensure uniform application of pressure and / or temperature even for molded parts with more complex geometries.This object is achieved in a device according to the preamble of patent claim 1 in that the second pressing section is at least partially spaced from the first pressing section in the direction of the movement axis and thatT. G / TG 220975WODecember 22, 2023 at least one curvature of the shape of the second pressing section, in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool, is configured to deviate at least partially from at least one curvature of the shape of the first pressing section, preferably from the curvature of the shape of the edge region of the first pressing section adjacent to the second pressing section. This provides a geometry of the pressing tool(s) that is particularly well adapted to workpieces or molded parts to be produced with complex geometries. If the corresponding pressing tool is provided, for example, for contacting the workpiece, a shape of the pressing tool(s) adapted to the workpiece can thus be provided.This provides uniform contact between the workpiece and the pressing tool, which simplifies uniform application of pressure and / or temperature. If, for example, the cavity is formed between the corresponding pressing tool comprising the pressing sections and the membrane, a cavity can be provided which has a substantially constant thickness, particularly in the closed position. The shape of the corresponding pressing tool can thus be adapted by the shape of the pressing sections such that, at least when the workpiece is subjected to pressure and / or temperature, the shape of the pressing sections is configured to correspond to the shape of the membrane and / or the workpiece. The at least one curvature of the shape of the second pressing section can differ, in particular in magnitude and / or sign, from the at least one curvature of the shape of the first pressing section.The second pressing section thus has a change in curvature compared to the first pressing section, so that the second pressing section and the first pressing section extend at least partially in different directions.T. G / TG 220975WODecember 22, 2023 The shape of the press sections describes the general shape of the respective section. Shape deviations, as described in DIN 4760:1982-06, preferably at least second-order and / or at least third-order and higher-order shape deviations, are not considered part of the shape or part of the curvature of the shape. Second-order shape deviations are waviness, and third- to fifth-order shape deviations are roughness. The curvature of the shape is therefore not considered a defect, especially a surface defect, in the pressing tools, especially in the press sections.In particular, the at least one curvature of the shape of the second pressing section is at least in sections smaller or larger than the at least one curvature of the shape of the first pressing section, preferably the curvature of the shape of the edge region of the first pressing section adjacent to the second pressing section, by at least a factor of 1.05, preferably at least a factor of 1.25, more preferably at least a factor of 2, more preferably at least a factor of 4, more preferably at least a factor of 10, more preferably at least a factor of 25, more preferably at least a factor of 50, more preferably at least a factor of 100, more preferably at least a factor of 250, more preferably at least a factor of 500, more preferably at least a factor of 1000, more preferably at least a factor of 2500, more preferably at least a factor of 5000, in particular at least a factor of 10000.The device comprises a first – preferably upper – pressing tool and a second – preferably lower – pressing tool; however, the device may comprise additional pressing tools. The first pressing tool and / or the second pressing tool may be formed as one or more parts. The first pressing tool and / or the second pressing tool are preferably made of metal, in particular nickel-rich steel, nickel-rich cast iron, or nickel-rich cast steel. The respective nickel content may be above 34%, T. G / TG 220975WODecember 22, 2023, preferably between 35.7% and 36.7% or between 40.8% and 43.6%. The use of metal, especially steel, can achieve a long service life for the pressing tools. Steels such as Invar 36 also have a very low coefficient of thermal expansion. The use of Invar therefore enables very precise production of molded parts, even with changing temperatures during the pressing process. Even greater advantages can be achieved with specially adapted casting alloys, preferably nickel-rich cast iron or nickel-rich cast steel, which not only keep the maximum coefficient of thermal expansion low but also largely adapt it to the requirements of the workpiece material, for example, a (glass- or carbon-fiber-reinforced) thermoset or a (glass- or carbon-fiber-reinforced) thermoplastic material, over large parts of the heating and cooling process in the pressing cycle.In addition, the use of cast materials offers significant economic advantages, as high-nickel alloy steels are extremely expensive and, even today, machining rates in mold making are often well over 50%, often even over 70% or 80%. The first pressing tool and the second pressing tool can be moved relative to each other between an open position and a closed position along a movement axis. This allows the pressing tools to be moved toward and away from a workpiece inserted into the press or the molded part produced from the workpiece. In the open position, the workpiece can be inserted between the pressing tools, or the finished molded part can be removed from between the two pressing tools. In the closed position, the workpiece can be subjected to pressure and / or heat to produce the molded part from the workpiece.The movement axis, in turn, specifies a defined movement of the pressing tools. The movement axis is the axis along which the pressing tools move relative to each other between the open and closed positions. Advantageously, the movement axis runs horizontally or vertically. Alternatively or additionally, the T runs. G / TG 220975WODecember 22, 2023 Movement axis through the first pressing tool and / or through the second pressing tool, in particular substantially centrally through the first pressing tool and / or the second pressing tool. Alternatively or additionally, the movement axis runs through the working space and / or the cavity, in particular substantially centrally through the working space and / or the cavity. In addition, the movement axis can run from the first pressing tool to the second pressing tool or vice versa. Furthermore, the movement axis can run parallel to the vertical axis of the first pressing tool and / or the second pressing tool, in particular the vertical axis of the device. The first pressing tool and / or the second pressing tool can advantageously also have a constant thickness, at least in sections, at least adjacent to the working space and / or the cavity, in particular in the direction of the movement axis.The device further comprises at least one at least partially elastically deformable membrane for contacting a workpiece. Because the membrane is at least partially elastically deformable, the membrane can adapt to the geometry of the workpiece or the molded part to be produced. The membrane can advantageously be linearly elastically deformable at least partially. The membrane is also advantageously provided for contacting the molded part to be produced and / or for subjecting the workpiece to pressure and / or temperature. The membrane is advantageously movable, preferably stretchable, more preferably elastically deformable, in particular linearly elastically deformable, at least partially in the direction of the working space, the cavity, the first pressing tool, and / or the second pressing tool. The membrane can also be substantially completely elastically deformable, in particular linearly elastically deformable.However, in the case of complex geometries of the workpiece or the molded part to be produced, it is advantageous if part of the membrane is plastically pre-formed and thus already before theT. G / TG 220975WODecember 22, 2023. The application of pressure and / or temperature to the workpiece is adapted to the shape of the workpiece or the molded part to be produced. The membrane is also made of metal in this case. This provides a sufficiently stable membrane that can withstand high pressures and / or high temperatures and also has high thermal conductivity. Furthermore, a metal membrane can be deformed both elastically and plastically, in particular plastically pre-deformed.A special feature of the present device is the use of a membrane made of metal in combination with a first pressing section and a second pressing section, wherein the second pressing section is at least partially spaced from the first pressing section in the direction of the movement axis, and the at least one curvature of the shape of the second pressing section is at least partially designed to deviate from the at least one curvature of the shape of the first pressing section, preferably from the curvature of the edge region of the first pressing section adjacent to the second pressing section. For pressing tools with such complex geometries and / or for workpieces with complex geometries, metal membranes can only be used to a limited extent or not at all. Metal membranes can, of course, deform elastically to a certain extent.Compared to membranes made of other materials, such as silicone, the elastic, particularly linear-elastic, deformability is rather low. A metal membrane can therefore only adapt to the geometry of the pressing tools and / or the workpiece to a certain extent through elastic deformation. However, this disadvantage can be compensated for, for example, by a plastically pre-formed mold section of the membrane. An advantage of metal membranes over, for example, silicone membranes is that metal membranes can withstand higher pressures and / or temperatures than silicone membranes. The membrane is preferably designed in one piece and / or in one part, in particular made from sheet metal. Advantageously, the T. G / TG 220975WODecember 22, 2023. Membrane thickness at least 0.05 mm, preferably at least 0.2 mm, in particular at least 0.25 mm. This ensures sufficient strength of the membrane. Alternatively or additionally, the membrane thickness is at most 4 mm, preferably at most 2 mm, in particular at most 1.5 mm. This ensures sufficient flexibility of the membrane. The membrane can preferably be made of steel, in particular stainless steel. In simple cases, it may be sufficient to use stainless steel according to material specification 1.4301 to manufacture the membrane. Preferably, however, steel, in particular stainless steel, with good to excellent deep-drawing properties, i.e., so-called deep-drawing steel, should be used to manufacture the membrane. The membrane can advantageously have a tensile strength of 300 to 850 MPa, in particular 310 to 540 MPa or 490 to 830 MPa.The membrane can in particular be made of a steel that contains at least the following proportions in weight percent as elements or compounds of: - Carbon in the range of approximately 0.16% to 0.22%, - Silicon up to approximately 0.13%, - Manganese in the range of approximately 0.2% to 0.4%, - Nickel up to approximately 0.25%, - Sulfur up to approximately 0.025%, - Phosphorus up to approximately 0.025%, - Chromium up to approximately 0.15%, - Aluminum in the range of approximately 0.02% to 0.07%, - Copper up to approximately 0.2%, with the remainder being iron and unavoidable impurities. The membrane can, for example, be made of hot-annealed steel strip or hot-rolled steel strip according to GOST 2284-79. G / TG 220975WODecember 22, 2023. Other steel alloys containing chromium, nickel, and advantageously also titanium and / or copper can also achieve good results. The diaphragm is advantageously arranged at least partially between the first pressing tool and the second pressing tool. Furthermore, the first pressing tool and / or the second pressing tool can be connected to the diaphragm. The device can also comprise two or at least two diaphragms. By using two or at least two diaphragms, pressure and / or temperature can be easily transferred to the workpiece from different sides. A cavity for a working medium is formed between the diaphragm and the first pressing tool and / or the second pressing tool, at least in the closed position.The cavity can also form between the membrane and the first pressing tool and / or the second pressing tool in the open position and the closed position, preferably in any position of the pressing tools. The cavity is preferably delimited at least in sections by the membrane and the first pressing tool and / or the second pressing tool. The cavity advantageously has a substantially uniform thickness at every point between the membrane and the first pressing tool and / or the second pressing tool, particularly along the longitudinal extent and / or transverse extent of the membrane. In other words, the cavity has a substantially constant thickness, at least in the closed position. The cavity can be filled with a working medium. The working medium is, for example, a gas or a liquid. The working medium can also preferably be subjected to pressure and / or temperature.The pressure and / or temperature to which the working medium can be subjected is transmitted to the workpiece via the diaphragm. The cavity is also advantageously expandable toward the working chamber. The cavity is pressurized with an oil pressure of at least 0.1 bar, preferably at least 2 bar, more preferably at least 6 bar, in particular at least 8 bar and / or T. G / TG 220975WODecember 22, 2023, a maximum of 40 bar, preferably a maximum of 26 bar, in particular a maximum of 22 bar, can be pressurized. The cavity can preferably also be sealed by the first pressing tool and / or the second pressing tool and the membrane against an oil pressure of at least 4 bar, advantageously at least 8 bar, in particular at least 40 bar. A working space for receiving the workpiece is also formed between the first pressing tool and the second pressing tool, in particular between the membrane and the first pressing tool and / or the second pressing tool. The working space is preferably formed at least in the open position and / or at least in the closed position, in particular in any position of the pressing tools. The workpiece can then be introduced into the working space in the open position and subjected to pressure and / or temperature in the closed position, in particular by means of the membrane.The surface of the first pressing tool and / or the surface of the second pressing tool has the first pressing section and the second pressing section. Therefore, both the surface of the first pressing tool and the surface of the second pressing tool can have a first pressing section and a second pressing section. However, the surface of the first pressing tool and / or the surface of the second pressing tool can have further pressing sections. The first pressing section and the second pressing section preferably adjoin one another, in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool. In this case, the first pressing section and the second pressing section border on the working space and / or the cavity. The pressing sections thus form the sections of the pressing tools that are intended for contact with the workpiece and / or for forming the shape of the cavity.The first pressing section and the second pressing section are in particular adjacent at least in the closed position, preferably at least in the closed position and the open position. G / TG 220975WODecember 22, 2023 position, to the working space and / or the cavity. In addition, the first pressing section and / or the second pressing section preferably point, in particular at least in the closed position, at least partially, preferably essentially completely, toward the working space and / or the cavity. The first pressing section and / or the second pressing section are preferably also designed to contact the workpiece. The pressing sections thus each form a contact surface for the workpiece. Due to the design of the pressing sections, the pressing tools are also suitable for receiving workpieces with complex geometries. The first pressing section and / or the second pressing section can extend straight at least partially, preferably essentially completely, and / or can extend curved at least partially, preferably essentially completely.The longitudinal extent of the corresponding pressing tool is the extent of the respective pressing tool, in particular starting from a transverse side of the respective pressing tool, along the longitudinal axis of the respective pressing tool. The transverse extent of the corresponding pressing tool is the extent of the respective pressing tool, in particular starting from a longitudinal side of the respective pressing tool, along the transverse axis of the respective pressing tool. The transverse extent of the corresponding pressing tool does not have to run exclusively, or may in some sections not run at all, in the direction of the transverse axis of the respective pressing tool.If, for example, the corresponding pressing tool extends at least partially in a circular arc around the longitudinal axis of the corresponding pressing tool, the transverse extension of the corresponding pressing tool runs proportionally in the direction of the transverse axis of the corresponding pressing tool and proportionally in the direction of the vertical axis of the corresponding pressing tool. This also applies accordingly to the longitudinal extension of the corresponding pressing tool. The longitudinal axis of the corresponding pressing tool and the transverse axis of the corresponding pressing tool are perpendicular to each other. G / TG 220975WODecember 22, 2023. A first embodiment of the device is characterized in that the second pressing section is spaced, at least in sections, from the first pressing section in the direction of the movement axis by a distance of at least 5 mm, preferably at least 50 mm, more preferably at least 150 mm, more preferably at least 200 mm, more preferably at least 300 mm, more preferably at least 500 mm, in particular at least 1000 mm. Such a spacing can simplify the uniform application of pressure and / or temperature to workpieces with complex geometries, since the pressing sections are better adapted to the geometry of such workpieces and a cavity with a more uniform thickness can be provided, at least when the workpiece is subjected to pressure and / or temperature.Alternatively or additionally, the distance can correspond to at least 1.25 times, preferably at least 1.41 times, more preferably at least 7 times, more preferably at least 25 times, more preferably at least 50 times, in particular at least 100 times, the membrane thickness. According to one embodiment of the device, it is provided that the at least one curvature of the shape of the second pressing section, in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool, is configured at least partially opposite to the at least one curvature of the shape of the first pressing section, preferably to the curvature of the edge region of the first pressing section adjacent to the second pressing section. This provides a shape of the pressing tools adapted to the geometry of the workpiece or the molded part to be produced.The pressing sections can thus provide more uniform contact with the workpiece or a cavity with a more uniform thickness, at least when the workpiece is subjected to pressure and / or temperature. Opposite curvatures are understood here to mean that the curvatures have opposite signs. For example, the first pressing section can be T. G / TG 220975WODecember 22, 2023 be curved to the left, thus having a positive sign, and the second pressing section be curved to the right, thus having a negative sign, or not curved, in which case the curvature is zero and the curvature has no sign. A positive sign, a negative sign, and no sign are each to be regarded as different signs. A further embodiment of the device is characterized in that the second pressing section extends, in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool, at least in sections obliquely to the first pressing section, and that, preferably, an angle of at least 90°, preferably at least 100°, in particular at least 120°, and / or an angle of at most 180°, preferably at most 160°, in particular at most 145°, exists between the first pressing section and the second pressing section, at least in sections.This provides a mold shape adapted to the geometry of the workpiece or the molded part to be produced. The mold sections can thus contact the workpiece more evenly or create a cavity with a more uniform thickness, at least when the workpiece is subjected to pressure and / or temperature.According to a further embodiment of the device, it is provided that the surface of the first pressing tool and / or the surface of the second pressing tool has a third pressing section, that the third pressing section is preferably at least partially spaced from the first pressing section and / or the second pressing section in the direction of the movement axis, and that the third pressing section is preferably at least partially spaced from the first pressing section and / or the second pressing section in the direction of the movement axis by a distance of at least 5 mm, preferably at least 50 mm, more preferably at least 150 mm, more preferably at least 200 mm, more preferably at least 300 mm, more preferably at least 500 mm, in particular at least 1000 mm. By providing a third pressing section, the shape of the pressing tools can be even more detailed and thus T. G / TG 220975WODecember 22, 2023 can be better adapted to the geometry of complex components. Appropriate spacing can simplify the uniform application of pressure and / or temperature to workpieces with complex geometries, as the pressing section is better adapted to the geometry of such workpieces or a cavity with a more uniform thickness can be provided, at least when the workpiece is subjected to pressure and / or temperature. Alternatively or additionally, the spacing can correspond to at least 1.25 times, preferably at least 1.41 times, more preferably at least 7 times, more preferably at least 25 times, more preferably at least 50 times, in particular at least 100 times, the membrane thickness. The third pressing section borders the working space and / or the cavity. The third pressing section also preferably borders the second pressing section.Advantageously, it can be provided that the third pressing section, in particular at least in the closed position, points at least partially, preferably substantially completely, toward the working space and / or the cavity. The third pressing section can also be designed to contact the workpiece. The third pressing section thus forms a contact surface for the workpiece. The third pressing section can also extend straight at least partially, preferably substantially completely, and / or extend curved at least partially, preferably substantially completely.The first pressing section, the second pressing section and / or the third pressing section can alternatively or additionally, in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool, have a length of at least 6 mm, preferably at least 50 mm, more preferably at least 70 mm, more preferably at least 100 mm, more preferably at least 150 mm, more preferably at least 500 mm, in particular at least 1000 mm.T. G / TG 220975WODecember 22, 2023 A further embodiment of the device provides that at least one curvature of the shape of the third pressing section, in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool, is designed to deviate at least partially from the at least one curvature of the shape of the first pressing section, and / or that the at least one curvature of the shape of the third pressing section is designed to deviate at least partially from the at least one curvature of the shape of the second pressing section, preferably from the curvature of the edge region of the second pressing section adjacent to the third pressing section. This provides a shape of the pressing tools adapted to the geometry of the workpiece or the molded part to be produced. The pressing section can thus contact the workpiece more evenly.provide a cavity with a more uniform thickness, at least when the workpiece is subjected to pressure and / or temperature. This applies in particular to workpieces with curved surfaces and / or surfaces that run obliquely to one another adjacent to the pressing sections. The at least one curvature of the shape of the third pressing section can differ, in particular, in magnitude and / or in sign from the at least one curvature of the shape of the first pressing section and / or the second pressing section. The third pressing section thus has a change in curvature compared to the first pressing section and / or the second pressing section, so that the third pressing section and the first pressing section and / or the second pressing section extend, at least in sections, in different directions.Advantageously, the at least one curvature of the shape of the third pressing section is at least partially at least a factor of 1.05, preferably at least a factor of 1.25, more preferably at least a factor of 2, more preferably at least a factor of 4, more preferably at least a factor of 10, more preferably at least a factor of 25, more preferably at least a factor of 50, more preferably at least a factor of 100, more preferably at least a factor of 250, more preferably at least a factor of 500, more preferably at least a factor of 1000, more preferably at least a factor of 2500, more preferably. G / TG 220975WODecember 22, 2023at least a factor of 5000, in particular at least a factor of 10000, smaller or larger than the at least one curvature of the shape of the first pressing section and / or the second pressing section, preferably of the edge region of the second pressing section adjacent to the third pressing section. It can also be provided that the third pressing section and the first pressing section and / or the second pressing section have substantially the same curvature and / or extend substantially parallel to one another.According to a further embodiment of the device, it is provided that the at least one curvature of the shape of the third pressing section, in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool, is configured at least partially opposite to the at least one curvature of the shape of the first pressing section and / or that the at least one curvature of the shape of the third pressing section, in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool, is configured at least partially opposite to the at least one curvature of the shape of the second pressing section, preferably to the curvature of the edge region of the second pressing section adjacent to the third pressing section. This provides a shape of the pressing tools adapted to the geometry of the workpiece or the molded part to be produced.The pressing sections can thus contact the workpiece more evenly or provide a cavity with a more uniform thickness, at least when the workpiece is subjected to pressure and / or temperature.A further embodiment of the device is characterized in that the third pressing section extends, in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool, at least in sections obliquely to the first pressing section and / or the second pressing section and that, preferably, between the third pressing section and the first pressing section and / or the second pressing section at least in sections a T. G / TG 220975WODecember 22, 2023An angle of at least 90°, preferably at least 100°, in particular at least 120°, and / or an angle of at most 180°, preferably at most 160°, in particular at most 145°. This provides a shape of the pressing tools adapted to the geometry of the workpiece or the molded part to be produced. The pressing sections can thus contact the workpiece more evenly or provide a cavity with a more uniform thickness, at least when the workpiece is subjected to pressure and / or temperature.A further embodiment of the device provides that the first pressing section, the second pressing section, and / or the third pressing section, in particular the shape of the first pressing section, the shape of the second pressing section, and / or the shape of the third pressing section, is curved at least in sections around the longitudinal axis of the device or an axis parallel to the longitudinal axis of the device, around the transverse axis of the device or an axis parallel to the transverse axis of the device, and / or around the vertical axis of the device or an axis parallel to the vertical axis of the device. This allows pressing tools with complex geometries to be provided. The pressing sections can thus contact the workpiece more evenly or provide a cavity with a more uniform thickness, at least when the workpiece is subjected to pressure and / or temperature. This applies in particular to workpieces or molded parts to be produced with complex geometries.It is preferably provided that the first pressing section, the second pressing section and / or the third pressing section, in particular the shape of the first pressing section, the second pressing section and / or the third pressing section, are curved at least in sections around at least two of the axes from the group consisting of the longitudinal axis of the device or an axis parallel to the longitudinal axis of the device, the transverse axis of the device or an axis parallel to the transverse axis of the device and the vertical axis of the device or an axis parallel to the vertical axis of the device. In other words, it is advantageous if the first pressing section, the second pressing section and / or the third pressing section, in particular the shape of the first pressing section, the shape of the second pressing section and / or the shape of the third T. G / TG 220975WODecember 22, 2023 Press section, at least partially curved about at least two mutually perpendicular axes. Thus, pressing tools are provided which are at least partially doubly curved. This makes it easy to produce molded parts with complex geometries, in particular a double curvature, or to provide a cavity with a more uniform thickness even in the case of molded parts with complex geometries. The longitudinal axis of the device and the transverse axis of the device are perpendicular to each other. The vertical axis, in turn, is perpendicular to the longitudinal axis of the device and perpendicular to the transverse axis of the device. The corresponding axes of the device are the axes of the device for producing molded parts.According to a further embodiment of the device, it is provided that the membrane, in particular along the longitudinal extent and / or the transverse extent of the membrane, has at least one elastically deformable base section for contacting the workpiece and at least one plastically pre-deformed shaped section for contacting the workpiece and that, preferably, at least in the open position, the shaped section, in particular along the longitudinal extent and / or the transverse extent of the membrane, is plastically pre-deformed relative to the base section. By combining the elastically deformable base section, which adapts very well to less complex geometries of the workpiece orof the molded part to be produced from the workpiece, and a plastically pre-deformed mold section, which is adapted to particularly complex geometries of the workpiece or of the molded part to be produced from the workpiece by the plastic pre-deformation before the workpiece is subjected to pressure and / or temperature, geometries of varying complexity can be subjected to pressure and / or temperature particularly evenly. G / TG 220975WODecember 22, 2023 The longitudinal extent of the membrane is the extent of the membrane, in particular starting from a transverse side of the membrane, along the longitudinal axis of the membrane. The transverse extent of the membrane is the extent of the membrane, in particular starting from a long side of the membrane, along the transverse axis of the membrane. The transverse extent of the membrane does not have to run exclusively in the direction of the transverse axis, or in some sections it may not run at all. If, for example, the membrane extends at least partially in a circular arc around the longitudinal axis of the membrane, the transverse extent of the membrane runs partially in the direction of the transverse axis of the membrane and partially in the direction of the vertical axis of the membrane. The same applies to the longitudinal extent of the membrane. The vertical axis of the membrane is the axis perpendicular to the longitudinal axis of the membrane and perpendicular to the transverse axis of the membrane.The longitudinal axis of the membrane and the transverse axis of the membrane are perpendicular to each other. The membrane can advantageously comprise at least two base sections, in particular a plurality of base sections, and / or at least two mold sections, in particular a plurality of mold sections. The base section is elastically, in particular linearly elastically, deformable and can thus adapt very well to the shape of the workpiece or the molded part to be produced. The mold section is in turn plastically pre-formed. This means that a shape has been imprinted on the mold section through plastic deformation, in particular relative to the base section. The mold section has been additionally plastically deformed relative to the base section through the plastic pre-deformation. The plastic pre-deformation occurs beyond the elastic limit of the membrane material.The plastic pre-deformation preferably leads to a plastic deformation at least on the side of the mold section adjacent to the cavity and / or at least on the side of the mold section adjacent to the working space, in particular substantially over the entire membrane thickness of the mold section. The shape of the mold section, particularly imposed by plastic pre-deformation, advantageously deviates from T. G / TG 220975WODecember 22, 2023 of the basic shape of the membrane, in particular the basic shape of the base section, at least in the open position of the pressing tools, in particular in the unloaded state of the membrane. The plastic pre-deformation aims to adapt the mold section, at least in sections, to the shape of the workpiece or the molded part to be produced from the workpiece using the device. Through the plastic pre-deformation, the mold section can be brought into a shape that the membrane could not achieve through elastic, in particular linear-elastic, deformation during the production of the molded part. The plastic pre-deformation of the mold section thus achieves a controlled adaptation of the shape of the mold section and thus the shape of the membrane, instead of plastically deforming the membrane in an uncontrolled manner when subjected to pressure and / or temperature. Uncontrolled plastic deformation of the membrane can lead to damage to the membrane.The mold section does not have to be completely plastically pre-formed; it is preferably sufficient for the mold section to be at least partially plastically pre-formed, preferably predominantly plastically pre-formed. However, it can also be advantageous if the mold section is essentially completely plastically pre-formed. The plastic pre-forming of the mold section does not, for example, mean a general plastic deformation of the entire starting material used for the membrane, for example in a rolling mill, or a plastic deformation that the membrane may undergo during the production of a molded part when subjected to pressure and / or temperature. The mold section is advantageously plastically pre-formed at least on the side of the mold section adjacent to the cavity and / or at least on the side of the mold section adjacent to the working space, in particular relative to the base section.By using a membrane made of metal with a plastically pre-deformed section, molded parts with complex geometries and under high pressures and / or temperatures can be produced. G / TG 220975WODecember 22, 2023, which would not be possible with non-metallic membranes, such as silicone membranes. While silicone membranes can adapt well to complex geometries of the workpiece or the molded part to be produced, silicone membranes can only withstand lower pressures and / or temperatures than metal membranes. The disadvantage of the lower flexibility of a metal membrane compared to, for example, a silicone membrane is compensated for in this case by the plastically pre-formed mold section, which is adapted to sections of the workpiece or the molded part to be produced with complex geometries. Advantageously, the mold section and the base section are also made of the same metal. It can also be provided that the base section and the mold section are formed together in one piece, in particular made of a single metal.Furthermore, it can be provided that the shape of the second pressing section corresponds to the shape of the molding section, in particular the shape of the surface of the molding section on the side adjacent to the cavity and / or the side of the molding section adjacent to the working space, and / or that the shape of the first pressing section and / or the third pressing section corresponds at least in sections to the shape of the base section, in particular the shape of the surface of the base section on the side adjacent to the cavity and / or the side of the base section adjacent to the working space. The base section and the molding section of the membrane are provided in particular along the longitudinal extent and / or the transverse extent of the membrane. The base section and the molding section advantageously extend along the longitudinal extent and / or the transverse extent of the membrane.Preferably, the base section and the shaped section adjoin one another, in particular along the longitudinal extent and / or the transverse extent of the membrane.It can also be provided that at least in the open position the shaped section and / or the base section, in particular the shape of the T. G / TG 220975WODecember 22, 2023 The shape of the mold section and / or the shape of the base section are curved, at least in sections, around the longitudinal axis of the membrane or an axis parallel to the longitudinal axis of the membrane, around the transverse axis of the membrane or an axis parallel to the transverse axis of the membrane, and / or around the vertical axis of the membrane or an axis parallel to the vertical axis of the membrane. This allows molded parts with complex geometries to be easily produced. In the case of the mold section, this curvature is imposed on the mold section by the plastic pre-deformation.Preferably, at least in the open position, the molded section and / or the base section, in particular the shape of the molded section and / or the shape of the base section, are curved at least in sections about at least two of the axes from the group consisting of the longitudinal axis of the membrane or an axis parallel to the longitudinal axis of the membrane, the transverse axis of the membrane or an axis parallel to the transverse axis of the membrane, and the vertical axis of the membrane or an axis parallel to the vertical axis of the membrane. In other words, it is advantageous if, at least in the open position, the molded section and / or the base section, in particular the shape of the molded section and / or the shape of the base section, are curved at least in sections about at least two axes running perpendicular to one another. Thus, a membrane is provided which is doubly curved at least in sections.In this way, molded parts with a complex geometry, in particular a double curvature, can be produced in a simple manner. Advantageously, it is provided that the mold section, preferably the shape of the mold section, is curved at least in sections about at least two axes running perpendicular to one another by plastic pre-deformation of the mold section, preferably relative to the base section. Furthermore, it can be provided that at least in the open position, the mold section, in particular on the side of the mold section adjacent to the cavity and / or on the side of the mold section adjacent to the working space, at least in sections from the base section, in particular the edge region of the base section adjacent to the mold section, in the direction of the cavity and / or inT. G / TG 220975WODecember 22, 2023 Direction of the working space, in particular substantially perpendicular to the surface of the edge region of the base section adjacent to the mold section, and that the distance corresponds at least to the membrane thickness. This provides a mold section that is adapted to complex geometries of the workpiece or the molded part to be produced. In particular, the mold section already provides sufficient space for projections of the workpiece or the molded part to be produced therefrom, both in the open position and during the application of pressure and / or temperature to the workpiece. In addition, a mold section designed in this way can be arranged sufficiently close to recesses of the workpiece or the molded part to be produced, so that a uniform contact of the mold section is achieved.A corresponding distance, for example in the direction of the cavity, can indeed lead to a larger cavity volume, since the distance between the membrane and the pressing tool is generally increased throughout to ensure sufficient distance between the mold section and the pressing tool. This may result in higher acquisition costs, higher operating costs, a higher risk of leaks, and increased inertia in temperature control. However, the advantage is achieved that at least a similar degree of uniformity of the pressure distribution acting in the pressing process is achieved in the mold section as is the case when considering the same overall process.Advantageously, the distance is present at least in the open position between the side of the mold section adjacent to the cavity and the side of the base section adjacent to the cavity and / or between the side of the mold section adjacent to the working space and the side of the base section adjacent to the working space. The distance can advantageously also be at least 6 mm, preferably at least 15 mm, more preferably at least 50 mm, in particular at least 72 mm, more preferably at least 1000 mm. Alternatively or additionally, the distance can be at least 1.25 times, preferably at least 1.41 times, more preferably at least 7 times, more preferably at least 25 times, more preferably at least 50 times, in particular at least 1000 mm. G / TG 220975WODecember 22, 2023, corresponding to 100 times the membrane thickness. The mold section can advantageously also be spaced from the base section by the distance in the direction of the vertical axis. It can also be provided that the membrane thickness of the mold section deviates by at most 40%, preferably at most 25%, more preferably at most 15%, in particular at most 10%, more particularly at most 5%, from the membrane thickness of the base section, in particular of the edge region of the base section adjacent to the mold section. This provides a membrane with a particularly uniform membrane thickness. In this case, the plastic pre-deformation of the mold section has only a minor influence on the membrane thickness of the mold section. The deviation in the membrane thickness advantageously exists along substantially the entire mold section.Advantageously, the mold section and the base section, in particular the edge region of the base section adjacent to the mold section, have substantially the same membrane thickness. It can also be provided that the mold section extends, in particular along the longitudinal extent and / or the transverse extent of the membrane, by at least 6 mm, preferably at least 50 mm, more preferably at least 70 mm, more preferably at least 100 mm, more preferably at least 150 mm, more preferably at least 500 mm, in particular at least 1000 mm. This provides a sufficiently large mold section that is also suitable for workpieces or molded parts to be produced with complex geometries of larger dimensions.A further embodiment of the device is characterized in that, at least in the open position, the curvature of the shape of the mold section, in particular along the longitudinal extent and / or transverse extent of the membrane, is designed to deviate at least in sections from at least one curvature of the shape of the base section, preferably from the curvature of the shape of the edge region of the base section adjacent to the mold section.T. G / TG 220975WODecember 22, 2023 This provides a pre-deformation of the mold section adapted to the geometry of the workpiece or the molded part to be produced. The curvature of the shape of the mold section can differ, in particular in magnitude and / or sign, from the at least one curvature of the shape of the base section. The mold section thus has a change in curvature compared to the base section, so that the mold section and the base section extend in different directions, at least in sections. The shape of the mold section or the shape of the base section describes the general shape of the respective section. Shape deviations, as described in DIN 4760:1982-06, preferably at least second-order and / or third-order and higher shape deviations, are not considered part of the shape or part of the curvature of the shape. In the case of second-order shape deviations,The third-order deviations are waviness, and the third- to fifth-order deviations are roughness. The curvature of the shape is therefore not a defect, especially a surface defect, in the membrane.In particular, the curvature of the shape of the mold section is at least in sections at least by a factor of 1.05, preferably at least by a factor of 1.25, more preferably at least by a factor of 2, more preferably at least by a factor of 4, more preferably at least by a factor of 10, more preferably at least by a factor of 25, more preferably at least by a factor of 50, more preferably at least by a factor of 100, more preferably at least by a factor of 250, more preferably at least by a factor of 500, more preferably at least by a factor of 1000, more preferably at least by a factor of 2500, more preferably at least by a factor of 5000, in particular at least by a factor of 10000, smaller or larger than the at least one curvature of the shape of the base section, preferably the curvature of the shape of the edge region of the base section adjacent to the mold section.The at least partial deviation of the curvature between the shape of the mold section and the at least one curvature of the shape of the base sectionT. G / TG 220975WODecember 22, 2023 is advantageously created by the plastic pre-deformation of the mold section, especially relative to the base section. The deviation in the curvature should therefore not, or at least not substantially, be a deviation in the curvature due to elastic deformation of the membrane, in particular due to gravity.It can also be provided that, at least in the open position, the curvature of the shape of the mold section on the side of the mold section adjacent to the cavity is configured to deviate at least partially from the at least one curvature of the shape of the base section, preferably from the curvature of the shape of the edge region of the base section adjacent to the mold section, on the side of the base section adjacent to the cavity, and / or the curvature of the shape of the mold section on the side of the mold section adjacent to the working space is configured to deviate at least partially from the at least one curvature of the shape of the base section, preferably from the curvature of the shape of the edge region of the base section adjacent to the mold section, on the side of the base section adjacent to the working space. This provides a pre-deformation of the mold section adapted to the geometry of the workpiece or molded part to be produced.In this case, it is particularly advantageous if both the curvatures on the side adjacent to the working space and the curvatures on the side adjacent to the cavity differ from one another, since this enables particularly extensive adaptation of the mold section to the geometry of the workpiece or the molded part to be produced. A further embodiment of the device provides that, at least in the open position, the curvature of the shape of the mold section, in particular along the longitudinal extent and / or transverse extent of the membrane, is designed at least in sections opposite to the at least one curvature of the shape of the base section, preferably to the curvature of the shape of the edge region of the base section adjacent to the mold section. G / TG 220975WODecember 22, 2023, a pre-deformation of the mold section adapted to the geometry of the workpiece or molded part to be produced is provided. In particular, this provides a mold section that is pre-deformed to suit more complex geometries of the workpiece or molded part to be produced. Opposite curvature is to be understood as the definition already explained in connection with the pressing sections. The at least partially opposite curvature between the shape of the mold section and the at least one curvature of the shape of the base section is advantageously created by the plastic pre-deformation of the mold section, in particular relative to the base section. The opposite curvatures should therefore not be caused, or at least not substantially caused, by elastic deformation of the membrane, in particular due to gravity.It can also be provided that, at least in the open position, the curvature of the shape of the mold section on the side of the mold section adjacent to the cavity is configured at least partially opposite to the at least one curvature of the shape of the base section, preferably to the curvature of the shape of the edge region of the base section adjacent to the mold section, on the side of the base section adjacent to the cavity, and / or the curvature of the shape of the mold section on the side of the mold section adjacent to the working space is configured at least partially opposite to the at least one curvature of the shape of the base section, preferably to the curvature of the shape of the edge region of the base section adjacent to the mold section, on the side of the base section adjacent to the working space. This provides a pre-deformation of the mold section adapted to the geometry of the workpiece or molded part to be produced.In this case, it is particularly advantageous if both the curvatures on the side adjacent to the working space and the curvatures on the side adjacent to the cavity are designed in opposite directions, since here a particularly extensiveT. G / TG 220975WODecember 22, 2023 Adaptation of the mold section to the geometry of the workpiece or the molded part to be produced is possible. According to a further embodiment of the device, the deviation of the curvature of the mold section from the at least one curvature of the base section, preferably from the curvature of the edge region of the base section adjacent to the mold section, is generated by means of plastic deformation, in particular of the shape, of the mold section. The deviation of the curvature, i.e., the deviation of the magnitude and / or the sign of the curvature, is thus to be generated by the plastic pre-deformation of the mold section. As a result, the mold section is permanently adapted to the geometry of the workpiece or the molded part to be produced.A further embodiment of the device provides that the cavity is sealed by at least one seal, at least in the closed position, and / or that the device comprises at least one device for varying the preload of the diaphragm. A corresponding seal prevents the working medium from leaking from the cavity in a structurally simple manner. A device for varying the preload of the diaphragm, in turn, has the advantage that, particularly before or at the beginning of the temperature and pressure exposure of the workpiece, the diaphragm is in uniform contact with the workpiece. The device for varying the preload of the diaphragm can be implemented, for example, by a spring with adjustable spring travel or adjustable preload.With regard to the seal, it can again be provided that a sealing force can be applied to the membrane via the seal, and that, preferably, the membrane is movable relative to the seal. Because the membrane is movable relative to the seal, changes in the length of the membrane, in particular due to thermal expansion or shrinkage, do not lead to excessive tension on the membrane or uneven contact with the workpiece or the molded part to be produced. Furthermore, the mobility of the membrane relative to the seal simplifies a T. G / TG 220975WODecember 22, 2023 Prestressing the membrane, since a prestress can then be applied to the membrane outside the area sealed by the seal. Advantageously, the device comprises at least one device for varying the sealing force of the seal. This allows a particularly tight seal of the cavity to be achieved. The object mentioned above is also achieved by the method for producing molded parts, in particular from fiber composite material, comprising the following steps: a) providing a workpiece, b) providing a device for producing molded parts according to one of claims 1 to 14, and c) applying pressure and / or temperature to the workpiece by means of the device for producing molded parts. The method advantageously also comprises the step b1) inserting the workpiece into the device for producing molded parts.Preferably, in step b1), the workpiece is placed into the work space. Furthermore, in step b1), the pressing tools are advantageously in the open position. The method preferably also comprises step b2): moving the first pressing tool and the second pressing tool from the open position to the closed position. Step b1) and / or step b2) preferably take place after step a) and / or step b). Alternatively or additionally, step b1) and / or step b2) preferably take place before step c). Furthermore, step b1) preferably takes place before step b2). The invention is explained in more detail below with reference to a drawing which merely illustrates preferred exemplary embodiments. In the drawing. zeigen: Fig. 1 shows a first embodiment of the device for producing molded parts in cross section, wherein the pressing tools of the device are in the open position,T G / TG 220975WODecember 22, 2023 Fig. 2 shows the device from Fig. 1, wherein a workpiece is placed in the working space of the device and the pressing tools of the device are in the open position, Fig. 3 shows the device from Fig. 1, wherein a workpiece is placed in the working space of the device and the pressing tools of the device are in the closed position, Fig. 4 shows a second embodiment of the device for producing molded parts in cross section, wherein the pressing tools of the device are in the open position, Fig. 5 shows the device from Fig. 4, wherein a workpiece is placed in the working space of the device and the pressing tools of the device are in the open position, Fig. 6 shows the device from Fig. 4, wherein a workpiece is placed in the working space of the device and the pressing tools of the device are in the closed position, and Fig.7 shows a section of a third embodiment of the device for producing molded parts in cross-section, with the pressing tools of the device in the closed position. Fig. 1 shows a first embodiment of the device for producing molded parts 1 in cross-section, with the pressing tools 2, 3 of the device in the open position. No workpiece has yet been inserted into the device. The device 1 comprises a first—upper—pressing tool 2 and a second—lower—pressing tool 3. The two pressing tools 2, 3 are T relative to one another. G / TG 220975WODecember 22, 2023, is movable along a movement axis B between an open position and a closed position, for example, in a vertical direction (indicated by arrows in Fig. 1). It is sufficient if only one of the two pressing tools 2, 3, in particular the first pressing tool 2, is movably mounted. The movement axis B can extend vertically, for example, as shown in Fig. 1. Furthermore, the device 1 comprises a membrane 4, which in the present embodiment is connected to the first pressing tool 2. As an alternative to the configuration shown in Fig. 1, the membrane 4 could also be connected, for example, to the second pressing tool 3. A cavity 5 for a working medium, for example, oil, is formed between the membrane 4 and the first pressing tool 2. The membrane 4 is made of metal and preferably has a thickness in the range between 0.05 mm and 4 mm.The cavity 5 can be filled with the working medium via a channel 6. Bores 7 are provided in both the first pressing tool 2 and the second pressing tool 3, through which a heating and / or cooling medium can be passed. Alternatively or additionally, the first pressing tool 2 and / or the second pressing tool 3 can also comprise a heating element, in particular an insertable heating plate, that can be inserted into the respective pressing tool 2, 3. In the embodiment of the device 1 shown in Fig. 1, a working space 8 is formed between the two pressing tools 2, 3, wherein in the present case the working space 8 is formed in particular between the membrane 4 and the second pressing tool 3. A workpiece (not shown in Fig. 1) can be inserted into the working space.The two pressing tools 2, 3 preferably have a guide 9, which can be formed, for example, by a projection 9A and a recess 9B, wherein the projection 9A can be provided on the second pressing tool 3 and wherein the recess 9B can be provided on the first pressing tool 2.T. G / TG 220975WODecember 22, 2023 In the present embodiment, the surface of the first pressing tool 2 and the surface of the second pressing tool 3 each have a first pressing section P1, P1', a second pressing section P2, P2', and a third pressing section P3, P3'. The pressing sections P1, P2, P3 of the first pressing tool 2 border the cavity 5, and the pressing sections P1', P2', P3' of the second pressing tool 3 border the working space 8. However, it may also be sufficient if only one of the pressing tools 2, 3 has a correspondingly designed surface with corresponding pressing sections P1, P1', P2, P2', P3, P3'. The second pressing section P2, P2' and the third pressing section P3, P3' of the two pressing tools 2, 3 are each at least partially spaced from the first pressing section P1, P1' of the respective pressing tool 2, 3.The curvature of the shape of the second pressing sections P2, P2' of the two pressing tools 2, 3 is also designed to be at least partially different and at least partially opposite to the curvature of the respective first pressing section P1, P1' and the curvature of the respective third pressing section P3, P3'. The respective second pressing section P2, P2' of the two pressing tools 2, 3 in this case each comprises a first bend KP1, KP1' and a second bend KP2, KP2'. In the area of ​​the bends KP1, KP1', KP2, KP2', the shape of the second pressing sections P2, P2' has a different curvature than the shape of the first pressing sections P1, P1' and the shape of the third pressing sections P3, P3', both in terms of the amount of the curvature and the sign of the curvature.Thus, the first pressing sections P1, P1' and the third pressing sections P3, P3', in particular in the edge region adjacent to the respective second pressing sections P2, P2', have a curvature of zero, since the first pressing sections P1, P1' and the third pressing sections P3, P3' each run straight. The second pressing sections P2, P2', however, have a curvature with an amount other than zero in the area of ​​the bends KP1, KP1', KP2, KP2' and thus a deviation in the curvature compared to the respective first pressing sections P1, P1' and third T. G / TG 220975WODecember 22, 2023 pressing sections P3, P3'. However, corresponding kinks can also be provided in the respective first pressing sections P1, P1' and / or third pressing sections P3, P3'. In the present embodiment, the second pressing sections P2, P2' do not extend parallel to the respective first pressing section P1, P1' and the respective third pressing section P3, P3', but rather obliquely in sections. In the embodiment shown, an angle of 45° exists between the respective second pressing section P2, P2' and the respective first pressing section P1, P1' and the respective third pressing section P3, P3'. In the embodiment shown, the membrane 4 is connected to the first pressing tool 2 in the following manner: The first pressing tool 2 has a circumferential edge element 10, which is connected to the first pressing tool 2, in particular by screwing (the screw connection is not shown in Fig. 1).A gap 11 is formed between the first pressing tool 2 and its edge element 10, through which the membrane 4 is guided. The gap 11 opens into a cavity 12 in which a clamping device 13 is provided, into which the membrane 4 is clamped. The clamping device 13 is connected to a tension rod 14, which is guided through an opening in the first pressing tool 2 and the edge element 10 and is pressed outward there by a spring 15 supported on the outer surface, whereby the membrane 4 is provided with a preload. The spring 15 is part of a device for varying the preload of the membrane 4. To seal the cavity 5, a seal 16 is provided in the gap 11, which allows movement of the membrane 4. The seal 16 presses against the membrane 4 with a sealing force. To change the sealing force, a device for changing the sealing force 17 of the seal 16 is provided.T. G / TG 220975WODecember 22, 2023 In the present view shown in Fig. 1, the transverse axis Q of the membrane 4 runs from left to right, the longitudinal axis L of the membrane 4 runs into the image plane of Fig. 1, and the vertical axis H of the membrane 4 runs from bottom to top. The axes are shown accordingly in Fig. 1 and the subsequent figures. Consequently, in Fig. 1, the transverse extension of the membrane 4 runs essentially from left to right or from right to left, and the longitudinal extension of the membrane 4 runs essentially into or out of the image plane of Fig. 1.The transverse axis Q of the membrane 4, the transverse axis of the device 1, the transverse axis of the first pressing tool 2 and the transverse axis of the second pressing tool 3, the longitudinal axis L of the membrane 4, the longitudinal axis L of the device 1, the longitudinal axis of the first pressing tool 2 and the longitudinal axis of the second pressing tool 3, as well as the vertical axis H of the membrane 4, the vertical axis H of the device 1, the vertical axis of the first pressing tool 2 and the vertical axis of the second pressing tool 3, each run in the same direction in this embodiment (as well as the other embodiments), so that the same reference numerals are used here for the respective corresponding axes. Consequently, the transverse extension of the pressing tools 2, 3 also runs essentially from left to right or from right to left, and the longitudinal extension of the pressing tools 2, 3 also runs essentially into or out of the image plane of Fig. 1. heraus.The membrane 4 has at least one elastically deformable base section G, G' for contacting the workpiece, in particular also the molded part to be produced, and at least one plastically pre-deformed mold section F for contacting the workpiece, in particular also the molded part to be produced. In the embodiment of the device 1 shown here, a first base section G is provided along the transverse extent of the membrane 4, the mold section F is adjacent to the first base section G, and a second base section G' is adjacent to the mold section F. The mold section F is plastically pre-deformed compared to the base sections G, G'. Due to the plasticT G / TG 220975WODecember 22, 2023 Pre-deformation imprints a shape on the mold section F that differs from that of at least one base section G, G', preferably both base sections G, G'. In the present embodiment, the mold section F does not extend parallel to the base sections G, G', but rather sections obliquely to the base sections G, G'. Due to the plastic pre-deformation of the mold section F, the device 1 can be used to machine workpieces with complex geometries and to produce molded parts with complex geometries. Particularly in devices 1 with a metal membrane 4, elastic deformation of the membrane 4, in order to follow the shape of workpieces or molded parts with complex geometries with the membrane 4, is only possible to a certain extent. Due to the plastic pre-deformation of the mold section F, the base sections G, G' are more elastically deformable than the mold section F.The base sections G, G' can deform more strongly than the mold section F through elastic, in particular linear-elastic, deformation in the direction of the working space 8. Nevertheless, the mold section F can, at least to a certain extent, continue to deform elastically. In this case, the mold section F has a kink K, K' at its outer regions along the transverse extent of the membrane 4. The kinks K, K' in the membrane 4 are created by the plastic pre-deformation of the mold section F compared to the base sections G, G'. In the region of the kinks K, K', the shape of the mold section F has a different curvature than the shape of the base section G, G', both in terms of the amount of the curvature and the sign of the curvature. Thus, the base sections G, G', in particular the edge region of the respective base section G, G' adjacent to the mold section F, have a curvature of zero, since the base sections G, G' are each straight.The shaped section F, on the other hand, has a curvature in the area of ​​the kinks K, K' with an amount not equal to zero and thus a deviation of the curvature compared to the basic sections G, G'.T. G / TG 220975WODecember 22, 2023 The deviation of the curvature as well as the presence of an opposite curvature lies in this case both between the curvature of the shape of the mold section F on the side of the mold section F adjacent to the cavity 5 and the curvature of the shape of the base sections G, G', preferably the curvature of the shape of the edge region of the base sections G, G' adjacent to the mold section F, on the side of the base sections G, G' adjacent to the cavity 5, as well as between the curvature of the shape of the mold section F on the side of the mold section F adjacent to the working space 8 and the curvature of the shape of the base sections G, G', preferably the curvature of the shape of the edge region of the base sections G, G' adjacent to the mold section F, on the side of the base sections G, G' adjacent to the working space 8. The mold section F extends in this case obliquely in sections, in particular at an angle of 45°, respectively to the basic sections G, G'.In this case, the mold section F is spaced at least in sections from the first base section G, in particular the edge region of the first base section G adjacent to the mold section F, in particular on the side of the mold section F adjacent to the cavity 5 and on the side of the mold section F adjacent to the working space 8, in particular substantially perpendicular to the surface of the edge region of the first base section G, and in sections from the second base section G', in particular the edge region of the second base section G' adjacent to the mold section F, in the direction of the working space 8, in particular substantially perpendicular to the surface of the edge region of the second base section G', each at a distance, the distance corresponding at least to the membrane thickness.The at least partial deviation of the curvature between the shape of the mold section F and the shape of the base sections G, G' is produced in the present case by means of plastic deformation, in particular by means of the plastic pre-deformation, of the mold section F. Despite this plastic deformation or pre-deformationT. G / TG 220975WODecember 22, 2023, the membrane thickness of the mold section F deviates by a maximum of 40% from the membrane thickness of the base sections G, G'. Fig. 2 shows the device from Fig. 1, wherein a workpiece 18 is inserted into the working space 8 of the device 1 and the pressing tools 2, 3 of the device 1 are in the open position. Those areas of the device 1 that have already been described are provided with corresponding reference numerals in Fig. 2. The difference from Fig. 1 is that the workpiece 18 has been inserted into the working space 8. Fig. 3 shows the device 1 from Fig. 1, wherein a workpiece 18 is inserted into the working space 8 of the device 1 and the pressing tools 2, 3 of the device 1 are in the closed position. Those areas of the device 1 that have already been described are also provided with corresponding reference numerals in Fig. 3.The device 1 has been closed, and the pressing tools 2, 3 are thus in the closed position, in that the two pressing tools 2, 3 have been moved toward each other. In the closed position shown in Fig. 3, the workpiece 18 is subjected to pressure and temperature. The pressure is applied by passing a working medium, for example oil, through the channel 6 into the cavity 5, thereby pressing the membrane 4 toward the workpiece 18. The temperature can be applied in different ways: One possibility is to heat the working medium passed through the channel 6 into the cavity 5, so that the heat from the working medium in the cavity 5 is transferred through the membrane 4 to the workpiece 18. Conversely, the working medium could be cooled to cool the workpiece 18.Alternatively or additionally, it can be provided that the bores 7 are flowed through by a heating and / or cooling medium, whereby first the two pressing tools 2, 3 and subsequently also the workpiece 18 can be heated or cooled.T. G / TG 220975WODecember 22, 2023 Fig. 4 shows a second embodiment of the device for producing molded parts 1 in cross-section, wherein the pressing tools 2, 3 of the device 1 are in the open position. A workpiece 18 has not yet been inserted into the working space 8 of the device 1. The second embodiment of the device 1 shown in Fig. 4 differs from the first embodiment of the device 1 shown previously in Figs. 1 to 3 essentially in the shape of the pressing tools 2, 3, in particular the shape of the pressing sections P1, P1', P2, P2', P3, P3', and the shape of the membrane 4. Identical components of the embodiments also have the same reference numerals. In the following, essentially only the differences between the embodiments will be discussed in more detail. In the second embodiment of the device 1, the pressing sections P1, P1', P2, P2', P3, P3' have a shape which, among other things, is composed of several circular arcs.The two pressing tools 2, 3 themselves also have, at least in sections, a shape composed, among other things, of several circular arcs. However, the shape of the pressing tools 2, 3 on the sides facing away from the cavity 5 and / or the working space 8 can also be designed differently. The second pressing section P2, P2' of each of the pressing tools 2, 3 has a substantially S-shaped form. The shape of the second pressing sections P2, P2', but also of the first pressing sections P1, P1' and the third pressing sections P3, P3', is adapted to the complex geometry of the workpiece 18 and the molded part to be produced therefrom, which workpiece 18 can be inserted into the working space 8 of the device 1.The curvature of the shape of the second pressing sections P2, P2' is designed to be different in sections, in particular opposite in sections, from the curvature of the shape of the respective first pressing section P1, P1' and the respective third pressing section P3, P3', in particular the edge region of the respective first pressing section P1, P1' and the respective third pressing section P3, P3' adjacent to the respective second pressing section P2, P2'. For example, the curvature of the shape of the second pressing sections P2, P2' in the region of the third bend KP3, KP3' runs opposite to T. G / TG 220975WODecember 22, 2023 at least one curvature of the shape of the respective first pressing section P1, P1' and the respective third pressing section P3, P3'. Due to the complexity of the shape of the respective second pressing section P2, P2', it might also be advisable to divide the second pressing section P2, P2' into further pressing sections. Furthermore, in the present embodiment, the membrane 4 has a shape in sections that is composed, among other things, of several circular arcs. The base sections G, G' have a substantially continuous curvature due to elastic deformation, in this case caused by gravity. The plastically pre-formed mold section F has a substantially S-shaped shape due to the plastic pre-deformation, in particular compared to the base sections G, G'. The shape of the mold section F is adapted to the complex geometry of the workpiece 18 and the molded part to be produced therefrom.The curvature of the shape of the mold section F is configured along the transverse extent of the membrane 4 to be at least partially different from, and in particular at least partially opposite to, the curvature of the edge region of the respective base section G, G' adjacent to the mold section F. Thus, the curvature of the shape of the mold section F in the region of the first bend K and the third bend K'' of the membrane 4 runs opposite to the curvature of the shape of the base sections G, G'. Fig. 5 shows the device 1 from Fig. 4, wherein a workpiece 18 is inserted into the working space 8 of the device 1 and the pressing tools 2, 3 of the device 1 are in the open position. Those regions of the device 1 that have already been described are provided with corresponding reference numerals in Fig. 4. The difference to Fig. 4 is that the workpiece 18 has been placed in the working space 8. Fig. 6 shows the device 1 from Fig.4, wherein a workpiece 18 is placed in the working space 8 of the device 1 and the pressing tools 2, 3 of the device 1 are in the closed position. Those areas of the device 1 whichT. G / TG 220975WODecember 22, 2023, are also provided with corresponding reference numerals in Fig. 6. According to Fig. 3 of the first embodiment, the device 1 was closed. The explanations for Fig. 3 apply accordingly to Fig. 6. Fig. 7 shows a section of a third embodiment of the device for producing molded parts 1 in cross section, wherein the pressing tools 2, 3 of the device 1 are in the closed position, with a workpiece 18 inserted into the working space 8. The third embodiment of the device 1 shown in Fig. 7 differs from the first embodiment of the device 1 shown previously in Figs. 1 to 3 and the second embodiment of the device 1 shown in Figs. 4 to 6 essentially in the shape of the pressing tools 2, 3, in particular the shape of the pressing sections P1, P1', P2, P2', P3, P3', and the shape of the membrane 4.Identical components of the embodiments also have identical reference numerals. In particular, the non-illustrated areas of the device 1 of this third embodiment can be configured according to Figures 1 to 6. The following essentially only describes the differences between the embodiment and the previous embodiments in more detail. In the present third embodiment, both the shape of the first pressing sections P1, P1' and the shape of the third pressing sections P3, P3' are each circularly arcuate. The second pressing section P2, P2' is configured differently, namely, the curvature of the respective second pressing section P2, P2' is at least partially different and opposite to the curvature of the respective adjacent first pressing sections P1, P1' and third pressing sections P3, P3'.For example, the curvature of the shape of the second pressing sections P2, P2' in the region of the first bend KP1, KP1' runs opposite to the curvature of the shape of the respective first pressing section P1, P1' and the respective third pressing section P3, P3'. In the illustrated embodiment, the second pressing section P2, P2' is approximately ST. G / TG 220975WODecember 22, 2023 and comprises a straight region, but the second pressing section P2, P2' can also each have a substantially continuously curved shape. The plastically pre-formed mold section F accordingly has an approximately S-shaped shape due to the plastic pre-deformation, in particular compared to the base sections G, G'. The mold section F comprises a straight region, but the mold section F can also have a substantially continuously curved shape. The shape of the mold section F is adapted to the complex geometry of the workpiece 18 and the molded part to be produced therefrom. In addition, the curvature of the mold section F along the transverse extent of the membrane 4 is configured at least in sections opposite to the curvature of the edge region of the respective base section G, G' adjacent to the mold section F.For example, the curvature of the shape of the shaped section F in the area of ​​the first bend K of the membrane 4 runs opposite to the curvature of the shape of the base sections G, G'.T. G / TG 220975WO December 22, 2023 List of reference symbols1 Device for producing molded parts2 First pressing tool3 Second pressing tool 4 Membran 5 Kavität 6 Kanal 7 holes8 working space 9 Führung 9A projection 9B recess 10 edge element 11 Spalt 12 Cavity13 Clamping device14 Tie rod 15 Feder 16 Seal 17 Device for changing the sealing force 18 Workpiece B Movement axis F Mold section G, G' Base section H Vertical axis K, K', K'' Bend of the membrane KP1, KP1', KP2, KP2', KP3, KP3' Bend of the pressing tool L Longitudinal axis T G / TG 220975WO December 22, 2023P1, P1' first press sectionP2, P2' second press sectionP3, P3' third press sectionQ transverse axisT G / TG 220975WO December 22, 2023

Claims

December 22, 2023 Patent Claims 1. Device for producing molded parts (1), in particular from fiber composite material, comprising: - a first pressing tool (2), - a second pressing tool (3), and - at least one at least partially elastically deformable membrane (4) for contacting a workpiece (18), - wherein the first pressing tool (2) and the second pressing tool (3) are movable relative to one another between an open position and a closed position along a movement axis (B), - wherein a cavity (5) for a working medium is formed between the membrane (4) and the first pressing tool (2) and / or the second pressing tool (3), at least in the closed position, - wherein a working space (8) for receiving the workpiece (18) is formed between the first pressing tool (2) and the second pressing tool (3) usbildet,- wherein the surface of the first pressing tool (2) and / or the surface of the second pressing tool (3) has a first pressing section (P1, P1') and a second pressing section (P2, P2'), - wherein the first pressing section (P1, P1') and the second pressing section (P2, P2') adjoin the working space (8) and / or the cavity (5), and - wherein the membrane (4) is made of metal, characterized in that the second pressing section (P2, P2') is spaced at least partially from the first pressing section (2) in the direction of the movement axis (B), and that at least one curvature of the shape of the second pressing section (P2, P2'), in particular along the longitudinal extent and / or the transverse extent - 2 - of the corresponding pressing tool (2, 3), is designed at least in sections to deviate from at least one curvature of the shape of the first pressing section (P1, P1'), preferably from the curvature of the shape of the edge region of the first pressing section (P1, P1') adjacent to the second pressing section (P2, P2').

2. Device (1) according to claim 1, characterized in that the second pressing section (P2, P2') is spaced at least in sections from the first pressing section (P1, P1') in the direction of the movement axis (B) by a distance of at least 5 mm, preferably at least 50 mm, more preferably at least 150 mm, more preferably at least 200 mm, more preferably at least 300 mm, more preferably at least 500 mm, in particular at least 1000 mm.3.Device (1) according to claim 1 or claim 2, characterized in that the at least one curvature of the shape of the second pressing section (P2, P2'), in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool (2, 3), is configured at least in sections opposite to the at least one curvature of the shape of the first pressing section (P1, P1'), preferably to the curvature of the shape of the edge region of the first pressing section (P1, P1') adjacent to the second pressing section (P2, P2').

4. Device (1) according to one of claims 1 to 3, characterized in that the second pressing section (P2, P2'), in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool (2, 3), extends at least in sections obliquely to the first pressing section (P1, P1') and that, preferably, between the firstT. G / TG 220975WO December 22, 2023 - 3 - pressing section (P1, P1') and the second pressing section (P2, P2') at least in sections an angle of at least 90°, preferably at least 100°, in particular at least 120°, and / or an angle of at most 180°, preferably at most 160°, in particular at most 145°, is present.5.Device (1) according to one of claims 1 to 4, characterized in that the surface of the first pressing tool (2) and / or the surface of the second pressing tool (3) has a third pressing section (P3, P3'), that, preferably, the third pressing section (P3, P3') is spaced at least partially from the first pressing section (P1, P1') and / or the second pressing section (P2, P2') in the direction of the movement axis (B), and that, preferably, the third pressing section (P3, P3') is spaced at least partially from the first pressing section (P1, P1') and / or the second pressing section (P2, P2') in the direction of the movement axis (B) by a distance of at least 5 mm, preferably at least 50 mm, more preferably at least 150 mm, more preferably at least 200 mm, more preferably at least 300 mm, more preferably at least 500 mm, in particular at least 1000 mm.6.Device (1) according to claim 5, characterized in that at least one curvature of the shape of the third pressing section (P3, P3'), in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool (2, 3), is designed to deviate at least in sections from the at least one curvature of the shape of the first pressing section (P1, P1'), and / or that the at least one curvature of the shape of the third pressing section (P3, P3') is designed to deviate at least in sections from the at least one curvature of the shape of the second pressing section (P2, P2'), preferably from the curvature of the shape of the third pressing section (P3, P3'). G / TG 220975WO December 22, 2023 - 4 - P3') adjacent edge region of the second pressing section (P2, P2').7.Device (1) according to claim 5 or claim 6, characterized in that the at least one curvature of the shape of the third pressing section (P3, P3'), in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool (2, 3), is configured at least in sections opposite to the at least one curvature of the shape of the first pressing section (P1, P1') and / or that the at least one curvature of the shape of the third pressing section (P3, P3'), in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool (2, 3), is configured at least in sections opposite to the at least one curvature of the shape of the second pressing section (P2, P2'), preferably to the curvature of the shape of the edge region of the second pressing section (P2, P2') adjacent to the third pressing section (P3, P3'). is.8.Device (1) according to one of claims 5 to 7, characterized in that the third pressing section (P3, P3'), in particular along the longitudinal extent and / or the transverse extent of the corresponding pressing tool (2, 3), extends at least in sections obliquely to the first pressing section (P1, P1') and / or the second pressing section (P2, P2') and that, preferably, between the third pressing section (P3, P3') and the first pressing section (P1, P1') and / or the second pressing section (P2, P2') at least in sections an angle of at least 90°, preferably at least 100°, in particular at least 120°, and / or an angle of at most 180°, preferably at most 160°, in particular at most 145°,. vorliegt. T G / TG 220975WO December 22, 2023 - 5 -9. Device (1) according to one of claims 1 to 8, characterized in that the first pressing section (P1, P1'), the second pressing section (P2, P2') and / or the third pressing section (P3, P3'), in particular the shape of the first pressing section (P1, P1'), the shape of the second pressing section (P2, P2') and / or the shape of the third pressing section (P3, P3'), is curved at least in sections about the longitudinal axis (L) of the device (1) or an axis parallel to the longitudinal axis (L) of the device (1), about the transverse axis (Q) of the device (1) or an axis parallel to the transverse axis (Q) of the device (1) and / or about the vertical axis (H) of the device (1) or an axis parallel to the vertical axis (H) of the device (1).10.Device (1) according to one of claims 1 to 9, characterized in that the membrane (4), in particular along the longitudinal extent and / or the transverse extent of the membrane (4), has at least one elastically deformable base section (G, G') for contacting the workpiece (18) and at least one plastically pre-deformed shaped section (F) for contacting the workpiece (18), and that, preferably, at least in the open position, the shaped section (F), in particular along the longitudinal extent and / or the transverse extent of the membrane (4), is plastically pre-deformed relative to the base section (G, G').11.Device (1) according to claim 10, characterized in that at least in the open position the curvature of the shape of the mold section (F), in particular along the longitudinal extent and / or transverse extent of the membrane (4), is designed at least in sections to deviate from at least one curvature of the shape of the base section (G, G'), preferably from the curvature of the shape of the edge region of the base section (G, G') adjacent to the mold section (F).T. G / TG 220975WO December 22, 2023 - 6 -12. Device (1) according to claim 10 or claim 11, characterized in that at least in the open position the curvature of the shape of the mold section (F), in particular along the longitudinal extent and / or transverse extent of the membrane (4), is configured at least in sections opposite to the at least one curvature of the shape of the base section (G, G'), preferably to the curvature of the shape of the edge region of the base section (G, G') adjacent to the mold section (F).

13. Device (1) according to claim 11 or claim 12, characterized in that the deviation of the curvature of the shape of the mold section (F) from the at least one curvature of the shape of the base section (G, G'), preferably from the curvature of the shape of the edge region of the base section (G, G') adjacent to the mold section (F), is produced by means of plastic deformation, in particular of the shape, of the mold section (F).14.Device (1) according to one of claims 1 to 13, characterized in that the cavity (5) is sealed at least in the closed position by at least one seal (16) and / or that the device (1) comprises at least one device for changing the prestressing of the membrane (4).

15. Method for producing molded parts, in particular from fiber composite material, comprising the following steps:a) providing a workpiece (18),b) providing a device for producing molded parts (1) according to one of claims 1 to 14, andc) applying pressure and / or temperature to the workpiece (18) by means of the device for producing molded parts (1).T. G / TG 220975WO December 22, 2023

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