Method for manufacturing a molded part

Abstract

The invention shows and describes a method for manufacturing a moulding, in particular a moulding made of a fibre composite material. In order to reduce the load on the film, the film (4, 4A', 4B') can be moved past the seal (16, 16') according to the invention, and in step c) the film can be moved past the seal (16, 16') at least in sections as a result of the expansion force (F A ).

Description

Technical Field

[0001] This invention relates to a method for manufacturing molded parts, particularly those made of fiber composite materials, comprising the following steps: a) providing an apparatus comprising: a first pressing tool, a second pressing tool, at least one membrane, and at least one seal, wherein the first pressing tool and the second pressing tool are movable relative to each other between an open position and a closed position, wherein a working cavity for a workpiece is formed between the first pressing tool and the second pressing tool, wherein the membrane is at least partially disposed between the first pressing tool and the second pressing tool, wherein the membrane is at least partially disposed in the working cavity, wherein at least one chamber 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, wherein the chamber is at least partially sealed by the seal, at least in the closed position, wherein, for sealing... The process includes: b) sealing the chamber, where a sealing force can be applied to the membrane via a seal, and wherein the membrane and the first pressing tool and / or the second pressing tool have different coefficients of thermal expansion; c) applying a sealing force to the membrane via a seal, wherein the chamber is sealed at least partially by applying the sealing force to the membrane, and wherein a frictional force exists between the membrane and the seal by the sealing force; d) applying pressure and / or temperature to the membrane, preferably via a working medium in the chamber, wherein the membrane expands at least partially in the working chamber, preferably more strongly than the first pressing tool and / or the second pressing tool, wherein the membrane is preferably pressured by the working medium in the chamber, wherein the pressure resists the expansion of the membrane into the chamber and thereby causes an expansion force along the membrane surface, and wherein the expansion force is at least adjacent to the seal resisting the frictional force between the membrane and the seal. Background Technology

[0002] Fiber composites refer to composite materials consisting primarily of two main components: reinforcing fibers and a plastic, with the fibers embedded within the plastic (“matrix” or “resin”). By combining the two main components, the composite material can generally exhibit better properties than if either component were considered alone. For example, the fibers contribute to the increased tensile strength of the composite material due to their high tensile strength in the fiber direction. Conversely, the matrix, for example, is responsible for holding the fibers in place and protecting them from mechanical and chemical influences.

[0003] One of the many possibilities for manufacturing components from fiber composites is based on the use of pre-prepared fiber-resin semi-finished products (so-called "prepregs," short for "prepreg fibers"). In these semi-finished products, the fibers contain a resin system that has not yet fully reacted, so that the semi-finished product exists in a flexible form (e.g., in a web-like shape on a roller). During component manufacturing, the prepreg is formed and hardened by completing a chemical reaction under high pressure and high temperature. This step can, for example, be carried out in a press.

[0004] Prepregs are processed extensively in industries such as aerospace. A challenge in processing them lies in the often highly complex component geometries required in aerospace, such as those due to reinforcing elements like longitudinal beams. Furthermore, minimizing installation costs necessitates the use of fewer, but therefore larger, components. This combination of complex geometries and large component dimensions places higher demands on the equipment and methods used to manufacture these components. For example, the membranes used in the equipment must be optimally adapted to the workpiece geometry to apply pressure and / or temperature uniformly to the workpiece without overloading the membrane.

[0005] For example, DE 10 2017 113 595 A1 provides an apparatus and method for manufacturing components made of fiber composite materials. Here, the component to be manufactured is introduced between two shells. The component to be manufactured is to be subjected to uniform pressure, wherein a flexible membrane acts on the component, and thus hydraulic pressure acts on the membrane from the side of the membrane away from the component. Therefore, the membrane is pressed against the surface of the component by the hydraulic pressure. In this way, even if the surface of the component is bent, it should be ensured that the hydraulic pressure acts evenly and therefore the force acting on the surface of the component by the membrane is the same magnitude at all locations, especially the force components acting orthogonally on the surface of the component are also the same magnitude.

[0006] The application of this “membrane press” for manufacturing components made of fiber composite materials is also disclosed in US 2016 / 0297153A1.

[0007] In these known presses, a flexible membrane is provided only on one side of the component, while a rigid tool is provided on the other side. Although this simplifies the structure of the press, it has the disadvantage that the geometry can only be matched to the workpiece, especially the workpiece that deforms during the pressing process, on the side of the flexible membrane.

[0008] Therefore, presses in which two membranes are arranged on opposite sides of the workpiece are also known. Such presses are known, for example, by WO 2018 / 167730 A1. The press shown there has two pressing elements, on which a membrane is fixed respectively (see Figure 4). Figure 5 Two membranes are rigidly connected to one of the pressing elements. While this immovable fixation of the membranes facilitates sealing of the chambers defined by the membranes and is structurally simple, it has drawbacks: the membranes cannot optimally fit the workpiece surface. Furthermore, due to their rigid tension, thermal expansion of the membranes cannot be compensated for. This leads to uneven pressure distribution, poor component quality, and the membranes bearing high loads, especially high stresses. Summary of the Invention

[0009] Therefore, the object of the present invention is to design and improve the method described at the beginning and in detail above, so as to reduce the load on the membrane.

[0010] This objective is achieved in a method for manufacturing a molded part by the following manner: the membrane is movable through the seal, and in step c), the membrane is moved through the seal due to expansion force.

[0011] The method according to the present invention is a method for manufacturing molded parts.

[0012] The method first includes step a), which involves providing equipment, particularly a press. This press is also known as a "membrane press". The equipment includes a first (e.g., upper) pressing tool, a second (e.g., lower) pressing tool, and at least one membrane.

[0013] The first and / or second pressing tools are preferably made of metal, more preferably steel, and especially of Invar. Using metal, particularly steel, results in a long service life for the pressing tools. Furthermore, Invar has a very low coefficient of thermal expansion. Therefore, workpieces, especially molded parts, can be machined or manufactured with great precision using Invar, even when temperatures change during the pressing process.

[0014] The membrane can be made of, for example, a thin metal sheet, preferably a thin steel sheet. Membranes made of metal sheets, especially steel sheets, have the advantages that, on the one hand, the membrane can transmit high pressure due to the mechanical properties of the metal, and on the other hand, the high thermal conductivity of the metal makes it well-suited for heating or cooling workpieces. Therefore, the membrane is advantageously configured to apply pressure and / or temperature to the workpiece. The membrane is preferably constructed as a single piece; however, it can also be constructed as multiple pieces. The device may also include two or at least two membranes. By using two or at least two membranes, pressure and / or temperature can be easily transferred to the workpiece from different sides, particularly to molded parts.

[0015] The device also includes at least one seal. This seal may be, for example, a graphite seal, which preferably has a wire mesh. Here, the seal may be disposed on a first pressing tool and / or a second pressing tool. Furthermore, the seal may extend at least sectionally substantially parallel to the membrane, particularly the membrane surface. Preferably, the seal is designed as a two-piece or at least two-piece unit.

[0016] The first and second pressing tools are movable relative to each other between an open position and a closed position. Thus, the press can be opened and closed. The relative movement between the first and second pressing tools, preferably between the open and closed positions, can be substantially linear, particularly vertical. Linear movement, especially vertical movement, enables simple and rapid adjustability of the pressing tools between the open and closed positions. In the closed position, the first and second pressing tools move toward each other and preferably at least partially contact each other. In the open position, the first and second pressing tools move away from each other, allowing a workpiece to be introduced between the two pressing tools. Besides the open and closed positions, the first and second pressing tools can also preferably move relative to each other to at least one intermediate position. Here, the at least one intermediate position is particularly arranged between the open and closed positions.

[0017] A working cavity for the workpiece is formed between the first and second pressing tools. Advantageously, this working cavity is formed at least in the closed position of the first and second pressing tools. The workpiece is, in particular, preferably a molded part made of a fiber composite material. Here, at least one workpiece can be introduced into the working cavity, preferably between at least one membrane, the first pressing tool, and / or the second pressing tool. In the working cavity, the workpiece can advantageously be subjected to pressure and / or temperature, at least in the closed position, especially by means of the membrane.

[0018] At least one chamber 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. Here, the chamber is preferably defined at least segmentally by the membrane and the first pressing tool and / or the second pressing tool. The chamber is thus determined to contain the working medium. In other words, the chamber can be filled with the working medium. Therefore, the membrane and the first pressing tool and / or the second pressing tool are advantageously connected to each other in a gas-tight and / or liquid-tight manner. The working medium is, for example, a gas or a liquid. Furthermore, the working medium is preferably capable of being pressured and / or heated. The pressure and / or temperature that can be applied to the working medium can be transmitted to the workpiece, especially by means of the membrane. The membrane is preferably deformable. Furthermore, the chamber is advantageously movable and / or deformable toward the workpiece, preferably adjacent to the membrane, especially by filling with the working medium and / or applying pressure and / or temperature. Advantageously, at least in the closed position, the at least one seal is at least segmentally disposed at the end of the chamber, and / or at least one end of the chamber is defined by the at least one seal. When two or more membranes are preferably provided, a chamber can be provided between the first pressing tool and the first membrane, and a second chamber is preferably provided between the second pressing tool and the second membrane.

[0019] The chamber can be sealed at least partially by a seal, at least in the closed position, and a sealing force can be applied to the membrane by means of the seal to seal the chamber. Here, the sealing force can be generated, for example, by extrusion force, which can be applied to a first pressing tool and / or a second pressing tool and can be transmitted to the at least one seal. The sealing force can also be generated, for example, alternatively or additionally, by means of the gravity of the components of the device.

[0020] Furthermore, the membrane and the first pressing tool and / or the second pressing tool have different coefficients of thermal expansion. Preferably, at least one membrane has a coefficient of thermal expansion greater than the corresponding coefficients of thermal expansion of the first pressing tool and / or the second pressing tool. Therefore, it is advantageous for the first pressing tool and / or the second pressing tool to be made of Invar steel, because Invar steel has a low coefficient of thermal expansion.

[0021] The method further includes step b): applying a sealing force to the membrane using a seal, wherein the chamber is at least partially sealed by applying the sealing force to the membrane, and wherein friction exists between the membrane and the seal due to the sealing force. The sealing force presses the seal against the membrane, preventing the working medium from leaking out of the chamber at least partially. The magnitude of the friction depends on the magnitude of the sealing force that causes it, often exhibiting a roughly linear relationship within certain limits (the ratio between the friction and the compressive force is also called the "coefficient of friction"). As the sealing force increases, the friction between the membrane and the seal also increases, for example. The friction preferably acts along the membrane surface and thus parallel to the surface of the membrane. Preferably, the friction acts substantially horizontally or substantially vertically. The friction is also oriented opposite to the movement of the membrane and / or the forces acting along the membrane surface and adjacent to the seal. Therefore, the friction preferably resists relative movement between the membrane and the seal. In particular, the friction resists movement of the membrane out of the working chamber and / or movement of the membrane into the working chamber.

[0022] Depending on whether there is relative motion between the seal and the diaphragm, friction can be static friction or sliding friction. Sliding friction exists if the seal and diaphragm move relative to each other. Static friction exists if the seal and diaphragm do not move relative to each other. If a sufficiently large force is applied to resist static friction, exceeding the static friction limit, relative motion occurs between the diaphragm and the seal, resulting in sliding friction between them.

[0023] The method further includes step c): applying pressure and / or temperature to the membrane, preferably using a working medium within the chamber. It may also be specified that pressure and / or temperature are additionally applied to the first pressing tool and / or the second pressing tool, particularly using the working medium within the chamber. To apply pressure and / or temperature to the membrane, the first pressing tool, and / or the second pressing tool using the working medium, it is preferable that the working medium itself is pressured and / or heated. Alternatively or additionally, pressure and / or temperature can be applied to the membrane, the first pressing tool, and / or the second pressing tool by applying pressure and / or temperature to them. Furthermore, by applying pressure and / or temperature to the membrane, the first pressing tool, and / or the second pressing tool, pressure and / or temperature can be applied to the workpiece in the working chamber. The membrane may preferably contact the workpiece at least segmentally and apply pressure and / or temperature to the workpiece.

[0024] In this context, applying temperature is understood in particular as heating and / or cooling.

[0025] Step c) further includes the membrane expanding at least sectionally within the working chamber, preferably more strongly than the first pressing tool and / or the second pressing tool. Through the expansion of the membrane, the membrane area increases and / or the membrane lengthens, particularly extending into the working chamber. The membrane, the first pressing tool, and / or the second pressing tool preferably expand thermally. Furthermore, the membrane, the first pressing tool, and / or the second pressing tool expand particularly due to applied pressure and / or temperature. To achieve expansion, temperature is applied, particularly heating. Alternatively or additionally, the membrane, the first pressing tool, and / or the second pressing tool may contract due to applied pressure and / or temperature. In this case, it can also be configured that the membrane contracts more strongly than the first pressing tool and / or the second pressing tool. To achieve contraction, applying temperature particularly involves cooling.

[0026] Therefore, the method may include step c1), wherein step c1) comprises: preferably applying pressure and / or temperature to the membrane, the first pressing tool, and / or the second pressing tool by means of a working medium in the chamber, wherein the membrane contracts at least segmentally within the working chamber, particularly thermodynamically. In particular, the membrane may be configured to contract more strongly than the first pressing tool and / or the second pressing tool. Step c1) may be performed before and / or after step c). Therefore, cooling of the membrane, the first pressing tool, and / or the second pressing tool may be prescribed before and / or after heating.

[0027] Step c) further includes applying pressure to the membrane, preferably by means of a working medium within the chamber. This application of pressure to the membrane can be, in particular, the applied pressure and / or temperature already described, preferably by means of a working medium within the chamber. However, the membrane may also be pressured alternatively or additionally in other ways.

[0028] Step c) further includes applying pressure to resist the expansion of the membrane into the chamber and thereby causing an expansion force along the membrane surface. Pressure refers to the pressure used to load the membrane. Through membrane expansion, the membrane area increases and / or the membrane lengthens, particularly the section of the membrane disposed in the working chamber. Here, the expansion of the membrane into the chamber, especially arching, can cause the membrane to no longer adhere substantially coherently to the workpiece to be processed or manufactured, and therefore cannot uniformly apply pressure and / or temperature to the workpiece. Furthermore, arching or folding of the membrane can lead to higher loads and thus damage to the membrane. To prevent this, sufficient pressure must be applied to resist the expansion of the membrane into the chamber, especially arching. Therefore, the pressure used to load the membrane is advantageously at least equal to, and preferably greater than, the pressure acting on the membrane towards the chamber, especially due to the expansion of the membrane.

[0029] "Along the membrane surface" is preferably understood here as in the direction of the membrane surface. Furthermore, the membrane surface is preferably the membrane surface adjacent to the workpiece to be processed or manufactured, at least in the closed position.

[0030] The expansion of the membrane into the cavity, especially the arching, is here understood in particular as the expansion of the membrane toward the adjacent cavity, and especially toward the cavity region adjacent to the expansion region of the membrane. If the membrane is oriented, for example, horizontally, then the expansion into the cavity is an expansion having at least one vertical component toward the adjacent cavity.

[0031] Furthermore, the pressure used to load the membrane and resist its expansion into the chamber causes an expansion force along the membrane surface. Here, the expansion force preferably acts at least segmentally, especially adjacent to the seal, along the membrane surface toward the seal or away from the seal.

[0032] The expansion force is preferably generated by at least partially discharging the pressure applied to the membrane along the membrane surface. Furthermore, due to the applied pressure, the membrane is pressed at least partially against the workpiece to be processed or manufactured. Thus, the membrane is at least partially clamped between the workpiece to be processed or manufactured and the pressure applied to the membrane. Because of this clamping, the membrane can expand at least partially, preferably substantially only substantially transverse to the clamping, and therefore along the membrane surface. This can also cause or at least affect the expansion force along the membrane surface.

[0033] Step c) further includes at least an expansion force adjacent to the seal resisting the frictional force between the membrane and the seal. When the membrane expands, the expansion force adjacent to the seal acts outward from the working chamber along the membrane surface. In this case, the frictional force resists the movement of the membrane out of the working chamber and / or the frictional force acts in the direction towards the working chamber along the membrane surface. When the membrane contracts, the frictional force resists the movement of the membrane into the working chamber and / or the frictional force acts away from the working chamber along the membrane surface. Furthermore, the expansion force preferably resists the frictional force between the membrane and the seal in the contact area between the seal and the membrane.

[0034] During step c), the membrane is at least partially in contact with the workpiece to be processed or manufactured, especially due to the application of pressure and / or temperature.

[0035] According to the present invention, the membrane can be moved through the seal, and in step c), due to the expansion force, the membrane is moved at least sectionally through the seal. By enabling the membrane to move through the seal, uniform adhesion of the membrane to the workpiece to be processed or manufactured can be ensured without subjecting the membrane to excessive load. When the membrane expands, the increased membrane area and / or the extended section of the membrane can also be drawn out from the working chamber. This avoids folding or arching of the membrane that could lead to film load. Thus, the membrane can be adhered substantially continuously to the workpiece to be processed or manufactured. When the membrane shrinks, the possibility of the membrane moving through the seal is also realized, and the area or section of the membrane can be added to the working chamber, especially in the range of reduced membrane area and / or shortened membrane. Therefore, the membrane can be adhered substantially continuously to the workpiece to be processed or manufactured, without being subjected to excessive load, especially tensile stress.

[0036] By causing the membrane to move at least partially through the seal due to the expansion force, the load on the membrane can also be reduced. To guide the membrane through the seal, especially during membrane expansion, pre-tensioning of the membrane can be omitted or at least reduced due to the expansion force. However, the expansion force does not necessarily cause the membrane to move through the seal alone. Therefore, it is preferably important that the sum of the forces acting along the membrane surface, resisting the friction between the membrane and the seal, and acting adjacent to the seal, is greater than the friction between the membrane and the seal. This sum of forces acting along the membrane surface, resisting the friction between the membrane and the seal, and acting adjacent to the seal, here includes at least the expansion force adjacent to the seal. Furthermore, preferably, the expansion force adjacent to the seal is the largest force acting along the membrane surface, resisting the friction between the membrane and the seal, and acting adjacent to the seal. By moving the membrane through the seal, the membrane is preferably tensioned and / or substantially continuously adhered to the workpiece to be processed or manufactured.

[0037] Here, when referring to a force and / or forces, we always start from the numerical values ​​of the corresponding force and / or forces.

[0038] The membrane can also be movable relative to the first pressing tool and / or relative to the second pressing tool, particularly due to expansion forces. Friction can also exist between the membrane and the first pressing tool, the second pressing tool, and / or another component of the apparatus. However, since the frictional force between the membrane and the seal is typically the greatest on the membrane and prevents it from moving past the seal, the membrane's movement past the seal depends on the frictional force between the membrane and the seal.

[0039] According to the first design of the method, steps b) and c) overlap at least in time. This ensures that the chamber is sufficiently sealed by the sealing force while the membrane can move past the seal. Step b) can in particular begin before step c) and / or end after step c). This reliably prevents leakage of the working medium from the chamber.

[0040] Another design of this method is configured such that the expansion force is greater than the frictional force between the membrane and the seal. This ensures reliable guidance of the membrane through the seal. Furthermore, membrane pre-tightening can be omitted or at least reduced. The expansion force specifically refers to the expansion force adjacent to the seal, which resists the frictional force between the membrane and the seal. Here, the expansion force is preferably greater than the frictional force between the membrane and the seal, at least partially during step b) and / or at least partially during step c), particularly continuously during step b) and / or continuously during step c). This ensures reliable membrane movement through the seal.

[0041] One design is characterized by the following steps, performed after step a) and preferably before step b) and / or before step c): a1) providing at least one workpiece, a2) placing the workpiece into the device, particularly into the working chamber, and a3) moving a first pressing tool and / or a second pressing tool to a closed position. The at least one workpiece may have a matrix and fibers embedded in the matrix. The fibers embedded in the matrix may be, for example, carbon fiber, glass fiber, aramid fiber, or the like. The fibers may be used, for example, as a semi-finished product in the form of a mat, nonwoven fabric, loose fabric, woven fabric, braided fabric, or knitted fabric. The matrix or resin may be formed, for example, from a thermoplastic plastic. The workpiece may be a completed “fiber matrix semi-finished product,” also referred to as a “prepreg.” To move the first pressing tool and / or the second pressing tool to the closed position, the pressing tools, preferably, move toward each other along the pressing axis. The movement of the first and / or second pressing tools toward the closed position may, in particular, be substantially linear. Preferably, step a1) is performed before step a2) and before step a3). Furthermore, step a2) is preferably performed after step a1) and before step a3). It can also be specified that step b) is performed before steps a1), a2), and a3), and step b) can in particular be performed at least before step a3). Thus, the chamber can be sealed and filled with the working medium before the first and second pressing tools move to the closed position.

[0042] According to another design of this method, the device provided in step a) includes at least one means for changing the membrane preload. The means for preloading the membrane can be implemented, for example, by a spring with adjustable travel or adjustable preload. Alternatively or additionally, preload can be achieved hydraulically and / or pneumatically by the means for preloading the membrane. With such means, the membrane preload can be set and can also be changed, for example, to adapt the preload to the workpiece to be manufactured or processed. The setting of preload and its variability makes it possible for the membrane to be preloaded before the workpiece is pressured and / or heated, especially before the working medium located in the chamber is pressured and / or heated. Similarly, the means for changing the membrane preload can, particularly during step c), jointly cause the membrane to move through the seal, preferably by applying a preload force to the membrane.

[0043] In one construction scheme, the method includes the following steps, performed after step a) and preferably before step b) and / or before step c): a4) pre-tightening the membrane by means of a device for changing the pre-tightness. Pre-tightening ensures that the membrane already has a smooth surface when it begins to act on the workpiece and is not under stress and thus "pulled smooth" only by the working medium located in the chamber. This has the advantage that a uniform action of the membrane on the workpiece is achieved at the beginning of the application of temperature and / or pressure, and the membrane preferably adheres substantially coherently to the membrane. By performing step a4) preferably before step b) and / or before step c), the membrane can already have pre-tightness before the membrane is pressured and / or temperatured, especially before the working medium located in the chamber is pressured and / or temperatured. Step a4) can be performed after steps a1), a2), and a3), or alternatively at least before step a3), especially before steps a1), a2), and a3). Furthermore, it is advantageously stipulated that steps a4) and steps b) and / or c) overlap at least in time. Furthermore, step a4) can be performed simultaneously with at least step b) and / or at least step c). In particular, step a4) can begin before and / or before step b) and end after and / or after step c). This ensures, especially during the membrane's movement past the seal, that sufficient pre-tension exists on the membrane.

[0044] Another embodiment of the method is characterized in that a pre-tightening force is applied to the membrane by pre-tightening the membrane according to step a4), and preferably, the pre-tightening force is less than the frictional force between the membrane and the seal, especially during step b) and / or step c). The pre-tightening force acts along the membrane surface and preferably resists the frictional force between at least one membrane and at least one seal, especially when the frictional force resists the movement of at least one membrane out of the working chamber. The pre-tightening force applied to the membrane by pre-tightening according to step a4) is preferably also applied to the membrane at least during step b) and / or at least during step c). The pre-tightening force thus enables, especially in step c), to jointly cause the membrane to move through the seal, such that a small expansion force is sufficient to move the membrane through the seal. By having a pre-tightening force, especially one that resists the frictional force between the membrane and the seal, less than the frictional force between the membrane and the seal, the load on the membrane can be reduced and thus the service life of the membrane can be increased. Particularly during step b) and / or step c), it is appropriate that the preload force resisting the friction between the membrane and the seal is less than the friction between the membrane and the seal, because the membrane has already been subjected to a high load by applying pressure and / or temperature in these steps. During step c), it also occurs particularly that the membrane has been substantially continuously pressed against the workpiece to be manufactured or processed due to the applied pressure, and the preload force may also be less than the friction between the membrane and the seal before and / or after steps b) and / or c).

[0045] In one embodiment of this method, during steps b) and / or c), the preload applied to the membrane is changed, particularly reduced, by means of a device for changing the preload. Thus, the load on the membrane can be kept as low as possible during the method, since high forces, especially during steps b) and / or c), act on the membrane. The preload can be changed according to the sealing force. Preferably, the preload decreases when the sealing force decreases, and / or increases when the sealing force increases. Alternatively or additionally, the preload can be changed according to the pressure and / or temperature applied to the membrane. Preferably, the preload decreases when the pressure and / or temperature decreases, and / or increases when the pressure and / or temperature increases. Furthermore, the preload can be changed before and / or after steps b) and / or c), preferably increased and / or decreased.

[0046] Another design of this method is characterized in that the sum of the expansion force and the preload, especially during step b) and / or step c), is greater than the frictional force between the membrane and the seal. This allows the membrane to overcome the frictional force and move past the seal. Preferably, this involves the expansion force adjacent to the at least one seal and the preload acting along the direction of the expansion force on the membrane. However, the expansion force does not necessarily cause the movement alone and can therefore be smaller. Thus, it can be advantageously configured that the expansion force adjacent to the seal is less than the frictional force between the membrane and the seal that preferably resists the expansion force. Preferably, in this case, the preload is also less than the frictional force between the membrane and the seal.

[0047] Another configuration of the method is to change the pressure and / or temperature of the working medium in the chamber during step b) and / or step c). By changing the pressure and / or temperature of the working medium in the chamber, the pressure and / or temperature acting on the membrane and / or workpiece can also be changed. Because both pressure and temperature can be changed, instead of constant pressure and constant temperature, changing pressure and temperature change curves can also be provided. For example, the pressure and / or temperature can be initially specified to increase, then the pressure and / or temperature can be specified to remain constant, and finally the pressure and / or temperature can be specified to decrease. For example, the pressure of the working medium can be changed by altering the amount of working medium in the chamber through the inflow or outflow of the working medium. Conversely, the temperature of the working medium can be changed, for example, by circulating the working medium and the inflowing working medium having a higher or lower temperature than the working medium located in the chamber, thus heating or cooling the working medium located in the chamber.

[0048] According to another embodiment of this method, the device provided in step a) includes at least one means for changing the sealing force, preferably adjacent to the seal. Furthermore, the frictional force acting on the membrane can be changed by the means for changing the sealing force. The variability of the sealing force can be achieved, for example, by an actuator acting on the seal, which presses the seal more strongly or weakly against the membrane surface. When two or more seals are provided, it is preferable to provide a means for changing the sealing force on each seal, such that the sealing force on each seal can be adjusted and changed independently of the other seals. By changing the sealing force during the application of pressure and / or temperature to the membrane, working medium, and / or workpiece, the mode of operation of the seal can be matched to the changing requirements during the method. Therefore, matching the mode of operation of the seal to the required conditions is particularly advantageous because the two objectives of particularly good sealing (high sealing force) and particularly good mobility of the membrane, especially good permeability of the membrane on the seal (low sealing force), cannot be achieved simultaneously and to a maximum extent; thus, there is a conflict of objectives. One possibility for resolving this conflict of objectives lies in prioritizing the competing objectives; for example, a good seal might be defined as a primary objective, while good membrane mobility might be defined as only a secondary objective. The priority of competing objectives can be shifted during the process by varying the sealing force. For instance, at the beginning of the method (e.g., during the heating phase with increasing temperature), membrane mobility could be defined as a primary objective because membrane expansion, especially thermal expansion, should be possible at this stage. This is achieved by setting a low sealing force between the membrane and the seal, and therefore low friction. Conversely, in further stages of the method (e.g., under constant high temperature and high pressure), a good membrane seal could be defined as a primary objective because of the high risk of leakage at this stage, while thermal expansion, in particular, is almost nonexistent due to the substantially constant temperature. This can be achieved by setting a higher sealing force and therefore higher friction between the membrane and the seal. Thus, the prioritization of competing objectives according to circumstances and needs can be achieved through the settable or variable nature of the sealing force.

[0049] One design of the method is characterized in that the device provided in step a) includes at least one second membrane, wherein at least one second chamber for the working medium is constructed between the at least one second membrane and the first pressing tool and / or the second pressing tool, at least in a closed position, wherein a sealing force can be applied to the second membrane by means of at least one second seal to seal the second chamber, and wherein the second membrane is movable past the second seal. The use of the second membrane enables multi-sided action on the workpiece even without flipping the membrane. Therefore, with the use of two separate membranes, the action on the workpiece can be particularly personalized, for example, to respond to local deformation of the workpiece. The at least one membrane may preferably be connected to the first pressing tool, and the at least second membrane may be connected to the second pressing tool. The at least one membrane and the at least second membrane may have the same thickness or different thicknesses. Furthermore, the at least one membrane, the at least second membrane, the at least one chamber and / or the at least second chamber may be subjected to substantially the same pressure and / or substantially the same temperature and / or may be subjected to different pressures and / or different temperatures, especially during step b) and / or step c). Furthermore, it is preferably specified that in step b), a frictional force is applied between the at least second membrane and the at least second seal by applying a sealing force to the at least second membrane. Furthermore, it is advantageously specified that in step c), pressure and / or temperature are preferably applied to the at least second membrane using a working medium in the at least second chamber, wherein the at least second membrane expands at least partially within the working chamber, preferably more strongly than the first and / or second pressing tool, wherein pressure is preferably applied to the at least second membrane using the working medium in the at least second chamber, wherein the pressure resists the expansion of the at least second membrane into the at least second chamber, and thereby causes a second expansion force along the membrane surface of the at least second membrane. At least adjacent to the at least second seal, the second expansion force resists the frictional force between the at least second membrane and the at least second seal. Furthermore, preferably, in step c), the at least second membrane is moved at least partially through the at least second seal due to the second expansion force.

[0050] According to one construction specification of the method, in step b) and / or step c), the pressure of the working medium located in the chamber is increased to at least 1.2 bar, especially 2 bar, and preferably, in step b) and / or step c), the pressure of the working medium located in the chamber is increased to a maximum pressure in the range of 10 bar to 50 bar, especially 15 bar to 30 bar. By increasing the pressure to at least 1.2 bar, especially 2 bar, a sufficiently large expansion force is particularly ensured to be applied along the membrane surface. However, this initial increase value is strongly dependent on the working chamber size of the press and the membrane thickness, and in some cases can be significantly higher, for example, at least 2.5 bar, 4 bar, 5 bar or even 8 bar. An empirical formula that can be applied here is 1.0 bar to 2.0 bar per initial millimeter of membrane thickness. Starting from these values, the working pressure is then controlled or adjusted. In some cases, the maximum pressure in step c) can then be increased to a maximum of 50 bar or even a maximum of 70 bar.

[0051] Alternatively or additionally, it may be specified that, in step b) and / or step c), the temperature of the working medium located in the chamber is increased to a maximum temperature between 280°C and 500°C, particularly between 310°C and 410°C. Preferably, in the presence of at least two chambers, the pressure and / or temperature of both chambers are increased accordingly. The aforementioned pressure and temperature achieve optimal results when manufacturing molded parts from fiber composite materials. The given values ​​are maximum values; lower pressure and temperature values ​​are also achieved during manufacturing in the press, for example, during the heating and cooling phases.

[0052] Finally, another embodiment of the method is characterized by comprising the following steps performed after step b) and / or after step c): c) opening the device and removing the workpiece. To open the device, the first pressing tool and / or the second pressing tool move relative to each other into an open position. In the open position, sufficient space exists between the pressing tools to allow for simple and quick removal of the workpiece. Attached Figure Description

[0053] The invention will now be further described with the aid of the accompanying drawings, which illustrate only one preferred embodiment. The drawings show:

[0054] Figure 1A A cross-section of a first design of an apparatus for implementing the method according to the invention, the apparatus being in the open position and without a workpiece inserted.

[0055] Figure 1B : Figure 1A With the device in the open position, the workpiece is placed inside.

[0056] Figure 1C : Figure 1A The equipment is in the off position, and the workpiece is placed in.

[0057] Figure 2 Shown in magnified view Figure 1C Part of the equipment area,

[0058] Figure 3 : Shown in enlarged view Figure 1C Part of the equipment,

[0059] Figure 4A A cross-section of a second design of an apparatus for implementing the method according to the invention, wherein the apparatus is in the open position and no workpiece is inserted.

[0060] Figure 4B ; Figure 4A With the device in the open position, the workpiece is placed inside.

[0061] Figure 4C : Figure 4A The device is in the closed position, the workpiece is placed in, and

[0062] Figure 5 : Figure 4C A magnified view of a portion of the device. Detailed Implementation

[0063] Figure 1A A first design of an apparatus 1 for implementing the method according to the invention is shown in cross-section in the open position without a workpiece inserted. Apparatus 1 includes a first upper pressing tool 2 and a second lower pressing tool 3. The two pressing tools 2 and 3 are movable relative to each other, for example, in the vertical direction (in... Figure 1A (Indicated by arrows). The two pressing tools 2 and 3 are movable relative to each other between an open position and a closed position. Furthermore, the press includes a membrane 4, which is arranged at least segmentally between the first pressing tool 2 and the second pressing tool 3. Here, the membrane 4 is connected to the first pressing tool 2. As an alternative to the design shown in Figure 1, the membrane 4 can also be connected to the second pressing tool 3. A chamber 5 for a working medium, such as 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 of 0.2 mm to 3.5 mm. The chamber 5 can be filled with the working medium through channels 6. Holes 7 are provided not only in the first pressing tool 2 but also in the second pressing tool 3, through which heating and / or cooling media can be guided.

[0064] exist Figure 1AIn the design of device 1 shown, a working cavity 8 is formed between the first pressing tool 2 and the second pressing tool 3, in which (… Figure 1A (The workpiece is not shown in the diagram). In this design, the working cavity 8 specifically includes a notch 8a in the second pressing tool 3. The two pressing tools 2 and 3 have guides 9, which can be formed, for example, by a protrusion 9A and a notch 9B, wherein the protrusion 9A can be provided on the second pressing tool 3, and wherein the notch 9B can be provided on the first pressing tool 2.

[0065] The membrane 4 is connected to the first pressing tool 2 in the following manner: the first pressing tool 2 has a surrounding edge element 10, which is screwed onto the first pressing tool 2 (the screwing part is in...). Figure 1A (Not shown in the image). 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 leads to a cavity 12 in which a clamping device 13 is disposed, clamping the membrane 4. The clamping device 13 is connected to a pull rod 14, which extends through an opening from the first pressing tool 2 and the edge element 10 and is there pushed outward by a spring 15 supported on the outer surface, thereby allowing the membrane 4 to be pre-tightened, particularly by a pre-tightening force F. v To seal chamber 5, a seal 16 is provided in gap 11, which allows the membrane 4 to move. Therefore, the membrane 4 can move through the seal 16. A device 17 for changing the sealing force is provided adjacent to the seal 16. Furthermore, a device 18 for changing the preload is provided adjacent to the spring 15.

[0066] Figure 1B Show Figure 1A Device 1 is in the open position, and workpiece 19 is inserted. The previously described areas of device 1 are... Figure 1B The corresponding figure labels are provided. (And...) Figure 1A The difference in the position shown is that the workpiece 19 has been placed into the working cavity 8, specifically into the notch 8A of the second pressing tool 3.

[0067] Figure 1C Show Figure 1A Device 1 is in the off position. The areas of Device 1 that have been previously described are... Figure 1C Corresponding reference numerals are also provided in the accompanying drawings. Device 1 is shut down by moving the two pressing tools 2 and 3 toward each other into the closed position. Figure 1CIn the position shown, workpiece 19 is loaded with pressure and / or temperature. Pressure is applied in such a way that a working medium, such as oil, is introduced into chamber 5 through channel 6, thereby pressing membrane 4 toward workpiece 19. Temperature can be applied in different ways: one possibility is that the working medium introduced into chamber 5 through channel 6 is heated, thereby transferring heat from the working medium located in chamber 5 to workpiece 19 through membrane 4. Conversely, the working medium can be cooled to cool workpiece 19. Optionally or additionally, the heating and / or cooling medium can be configured to flow through orifice 7, thereby heating or cooling the two pressing tools 2, 3 first and then heating or cooling membrane 4 and workpiece 19. Membrane 4, first pressing tool 2 and / or second pressing tool 3 can be subjected to pressure and / or temperature in the same manner. Due to the effect of pressure, workpiece 19 is subjected to pressure and / or temperature. Figure 1C It is compressed at the position shown.

[0068] Figure 2 Shown in magnified view Figure 1C A portion of device 1. Those previously described areas of device 1 are in... Figure 2 The corresponding appendix also includes corresponding reference numerals. Figure 2 The tension and sealing of membrane 4 can be clearly seen in the image. A sealing force F is applied to membrane 4 through seal 16. D Preferably, the sealing force F is achieved through the sealing element 16. D By pushing against membrane 4, chamber 5 is sealed at least partially. Sealing force F D It acts perpendicularly on the surface of membrane 4, that is, on Figure 2 The center is roughly vertical. Sealing force F D The magnitude of the sealing force can be changed by means of a device 17 for changing the sealing force. This can be done, for example, by means of an actuator 17 for changing the sealing force, which compresses the seal 16 against the membrane 4 with a larger or smaller force. A larger sealing force F D This results in a more reliable seal, however, it restricts the mobility of membrane 4. Conversely, a smaller sealing force F D Improving the mobility of membrane 4, however, leads to a poorer seal and the associated risk of leakage. Therefore, the sealing force F D The size can be adjusted to an optimal value according to the method parameters (especially the pressure and / or temperature in chamber 5) by means of the device 17 for changing the sealing force.

[0069] exist Figure 2 The sealing force F shown in the figure D This results in a frictional force F between the membrane and the seal. R Frictional force F R It acts along the membrane surface and therefore parallel to the surface of membrane 4, i.e., in Figure 2 The frictional force F is roughly horizontal.R The frictional force F always points in the opposite direction to the motion of membrane 4; because membrane 4 can expand and contract, especially due to heat, the frictional force F... R Therefore, they can have different directions (in) Figure 2 (Indicated by double arrows). For example, when membrane 4 expands in working chamber 8, the frictional force F R The frictional force F resists the movement of the membrane 4 out of the working chamber 8. When the membrane 4 contracts within the working chamber 8, the frictional force F... R The resistance membrane 4 moves into the working chamber 8. Frictional force F R The size depends on the sealing force F that produces it. D The magnitude of friction and compressive force usually exhibits a roughly linear relationship within a certain range (the ratio between friction and compressive force is also known as the "coefficient of friction").

[0070] In addition, Figure 2 The preload F is shown in the figure. v Through this preload F v Pre-tension membrane 4. Pre-tension force F v Along the membrane surface and therefore parallel to the surface of membrane 4, that is, in Figure 2 The preload force F acts roughly in the horizontal direction. v The size can also be adjusted or changed, specifically through the device 18 for changing the preload. Preload F v Adjustments or changes can be made, for example, by changing the preload of spring 15.

[0071] Figure 3 It shows Figure 1C A partial enlarged view of device 1. The two pressing tools 2 and 3 are in the closed position. Pressure and / or temperature are applied to the membrane 4, so that the workpiece 19 can also be pressured and / or heated by means of the membrane. To achieve uniform loading of the workpiece 19 with pressure and / or temperature, the membrane 4 should be substantially continuously attached to the workpiece 19. However, due to the pressure and / or temperature applied to the membrane 4, expansion of the membrane 4—especially thermal expansion—may occur. The two pressing tools 2 and 3 may also expand due to the applied pressure and / or temperature, especially thermal expansion. The expansion of the membrane 4 is generally stronger than the expansion of the pressing tools 2 and 3. This is because the coefficient of thermal expansion of the material used to manufacture the membrane 4 is generally lower than that of one or more materials used to manufacture the pressing tools 2 and 3. The pressing tools 2 and 3 are, for example, made of indium steel. Due to the expansion of the membrane 4, the membrane area of ​​the membrane 4 increases and / or the membrane 4 elongates, thereby posing a risk that the expanded membrane 4 expands into the chamber 5, especially arching into the chamber 5. The expansion of the membrane 4 into the chamber 5... Figure 3The expansion of the membrane 4 into the chamber 5 is illustrated exemplarily by means of dashed lines. The expansion of the membrane 4 into the chamber 5 causes the membrane 4 to detach from the workpiece 19, thus no longer adhering substantially coherently to the workpiece 19, and the workpiece 19 cannot be uniformly subjected to pressure and / or temperature by means of the membrane 4. To suppress the expansion of the membrane 4 into the chamber 5, pressure is applied to the membrane 4, particularly by means of the working medium in the chamber 5. This pressure application can be, in particular, the pressure and / or temperature applied to the membrane 4 by means of the working medium in the chamber 5, as already described above. Here, the pressure used to load the membrane 4 must be at least as large as, preferably larger than, the pressure at which the membrane 4 expands towards the chamber 5.

[0072] An expansion force F is generated along the membrane surface of membrane 4 by applying pressure to membrane 4. A Here, the expansion force F A Preferably, this is achieved by means that the pressure applied to the membrane 4 is at least partially directed along the membrane surface of the membrane 4. Furthermore, by applying pressure to the membrane 4, the membrane 4 is at least sectionally pressed against the workpiece 19 to be processed or manufactured. Thus, the membrane is at least sectionally "tensioned" between the workpiece 19 and the pressure applied to the membrane 4. Figure 3 (Indicated by arrows). Due to this tension, membrane 4 can expand essentially only along its surface, which also contributes to the generation of an expansion force F along its surface. A .

[0073] In order to prevent the expanded or inflated membrane 4 from detaching from the workpiece 19, but rather to maintain it substantially continuously against the workpiece 19, the enlarged and / or extended area or section of the membrane 4 must be guided out of the working chamber 8. Otherwise, membrane folding may occur adjacent to the pressing tools 2, 3, and especially adjacent to the gap 11. To guide the membrane 4 out of the working chamber 8 at least sectionally, the membrane 4 must move through the seal 16. Here, the membrane 4 moves through the seal 16 by the expansion force F. A This causes the expansion force to act along the membrane surface of membrane 4. However, the frictional force F R The resistance membrane 4 moves past the seal 16, and the frictional force is due to the sealing force F. D It is applied between the membrane 4 and the seal 16. Therefore, the expansion force F A Resisting frictional force F adjacent to at least seal 16 R In order for the membrane 4 to move past the seal 16, a frictional force F acting along the membrane surface of the membrane 4, resisting the friction between the membrane 4 and the seal 16, is formed. R Furthermore, the sum of the forces acting immediately adjacent to the seal 16 must preferably be greater than the frictional force F between the membrane 4 and the seal 16. R The frictional force F acting along the membrane surface of membrane 4, resisting the friction between membrane 4 and seal 16. RFurthermore, the sum of the forces acting immediately adjacent to seal 16 includes at least the expansion force F immediately adjacent to seal 16. A Preferably, the expansion force F A Greater than the frictional force F R Therefore, no additional force is needed to move the membrane 4 past the seal 16. However, the preload F applied to the membrane 4 can be changed by a device for adjusting the preload. v This can also additionally aid in the movement of membrane 4 past seal 16. In this case, the expansion force F adjacent to seal 16 A and expansion force F A Preload F acting in the same direction v The sum must be greater than the resistance expansion force F between membrane 4 and seal 16. A Frictional force F R To simplify the movement of membrane 4 through seal 16, the sealing force F can be reduced by means of device 17 for changing the sealing force during membrane loading with pressure and / or temperature. D .

[0074] After sufficient pressure and / or temperature are applied to workpiece 19, the two pressing tools 2 and 3 move back to the open position, as shown. Figure 1A and 1B As shown. Then, the workpiece can be removed from device 1.

[0075] Figure 4A A second design of the device 1' for implementing the method according to the invention is shown in cross-section in the open position without a workpiece inserted. Device 1' and Figures 1A to 3 The main difference between device 1 and device 1' is that device 1' includes a second membrane 4B'. However, the working principles of the two devices 1 and 1' are basically the same. Therefore, the differences between the two devices 1 and 1' will be discussed in particular here.

[0076] Figure 4A The device 1' shown includes a first upper pressing tool 2' and a second lower pressing tool 3'. The two pressing tools 2' and 3' are positioned between an open position and a closed position, for example, in the vertical direction (in...). Figure 4A(Indicated by arrows) They move relative to each other. Furthermore, device 1' includes a first upper membrane 4A' and a second lower membrane 4B', wherein the first membrane 4A' is connected to a first pressing tool 2', and wherein the second membrane 4B' is connected to a second pressing tool 3'. A first chamber 5A' for a working medium is formed between the first membrane 4A' and the first pressing tool 2' connected thereto, and a second chamber 5B' for a working medium is formed between the second membrane 4B' and the second pressing tool 3' connected thereto, wherein the working medium may be, for example, oil. Membranes 4A' and 4B' are made of metal and preferably have a thickness in the range of 0.2 mm to 3.5 mm. Chambers 5A' and 5B' can each be filled with a working medium through a channel 6'. Holes 7' are provided not only in the first pressing tool 2' but also in the second pressing tool 3', through which heating and / or cooling media can be guided.

[0077] In addition, Figure 4A The device 1 shown has a working cavity 8', in which (in) Figure 4A (Workpiece not shown). The working cavity 8' extends partially into the first pressing tool 2' and partially into the second pressing tool 3'. The two pressing tools 2', 3' have guides 9', which can be formed, for example, by a protrusion 9A' and a notch 9B', wherein the protrusion 9A' can be provided on the second pressing tool 3', and wherein the notch 9B' can be provided on the first pressing tool 2'.

[0078] The first membrane 4A' is connected to the first pressing tool 2' in the following manner (the same applies to the second membrane 4B' and the second pressing tool 3'): the first pressing tool 2' has a gap 11' in its edge region, through which the first membrane 4A' is guided. The gap 11' leads to a cavity 12', in which a clamping device 13' is disposed, and the first membrane 4A' is clamped into the clamping device. The clamping device 13' is connected to a pull rod 14', which extends through an opening from the first pressing tool 2' and is there pushed outward by a spring 15' supported on the outer surface, thereby allowing the first membrane 4A' to be pre-tightened, particularly by a pre-tightening force F. v Furthermore, a device 18' for changing the preload is provided adjacent to the spring 15', which allows for changing the preload, especially the preload force F. v To seal the first chamber 5A', a seal 16' is provided in the gap 11', which allows movement of the first membrane 4A'. Furthermore, a device 17' for changing the sealing force is provided adjacent to the seal 16'.

[0079] Figure 4B Show Figure 4ADevice 1' is in the open position, and workpiece 19' is inserted. The previously described areas of device 1' are... Figure 4B The corresponding figure labels are provided. (And...) Figure 4A The difference in the positions shown is that workpiece 19' is placed into the working cavity 8' of the pressing tool 3'. In addition to workpiece 19', two additional workpieces 19A' are placed into the working cavity 8' of the device 1. Workpiece 19A' can be, for example, a pre-fabricated reinforcing element with a Z-shaped cross-section (e.g., a "longitudinal beam" of an aircraft fuselage). Workpiece 19A' should be connected to workpiece 19' in subsequent manufacturing steps. To achieve uniform pressure distribution even when workpiece 19A' has a complex geometry, multiple cores 20' are placed in the working cavity. The shapes of these cores match the shape of the working cavity 8' and the shapes of workpieces 19' and 19A'.

[0080] Figure 4C Shown in the closed position Figure 4A Device 1'. The areas of Device 1' that have been described previously are in Figure 4C Corresponding reference numerals are also provided in the accompanying drawings. Device 1' is closed by moving the two pressing tools 2' and 3' towards each other into the closed position. Figure 4C In the closed position shown, pressure and / or temperature are applied to the workpiece 19'. The pressure and / or temperature are applied according to the operating mode described in conjunction with the first design scheme of the device 1 used to implement the method. In the present second embodiment, the two chambers 5A', 5B' can be filled with the working medium independently of each other; however, it is preferable that the two chambers 5A', 5B' are filled with the working medium uniformly. Similarly, the working medium in the two chambers 5A', 5B' and / or the two membranes 4A', 4B' are pressured and / or temperature-treated independently of each other. Alternatively or additionally, the working medium in the two chambers 5A', 5B' and / or the two membranes 4A', 4B' are pressured and / or temperature-treated uniformly.

[0081] Figure 5 Shown in enlarged view Figure 4C Part of the device 1'. Two pressing tools 2' and 3' are in the closed position. Two membranes 4A' and 4B' are subjected to pressure and / or temperature so that workpiece 19' is also subjected to pressure and / or temperature by means of membranes 4A' and 4B'. In addition, a sealing force F is applied to the respective membranes 4A' and 4B' by means of seal 16'. D Preferably, a sealing force F is applied through a corresponding sealing element 16'. D The pressure is applied to the corresponding membranes 4A' and 4B', and the chambers 5A' and 5B' are sealed at least section by section. Sealing force F D Acting perpendicularly on the surfaces of the corresponding membranes 4A' and 4B', that is, at Figure 5The center is roughly in the vertical direction. Sealing force F D The size can be changed by corresponding devices 17' for changing the sealing force, wherein each device 17' for changing the sealing force can independently change the corresponding sealing force F. D However, these devices 17' used to change the sealing force preferably change the corresponding sealing force F uniformly. D As already described for the first design of device 1 used to implement the method, the corresponding sealing force F D This results in a corresponding frictional force F between the respective membranes 4A', 4B' and the respective seal 16'. R Here, the frictional force F R It acts along the corresponding membranes 4A' and 4B' and therefore parallel to the corresponding membranes 4A' and 4B'.

[0082] The second design of device 1' also presents the following problem: due to the applied pressure and / or temperature, membranes 4A' and 4B' may undergo, particularly thermodynamic, expansion. The two pressing tools 2' and 3' may also undergo, similarly, thermodynamic, expansion due to applied pressure and / or temperature, with membranes 4A' and 4B' typically expanding more strongly than the pressing tools 2' and 3'. As already described with respect to the first design of device 1, the corresponding membrane areas of membranes 4A' and 4B' increase, and / or membranes 4A' and 4B' elongate, thereby posing the risk that the expanded membranes 4A' and 4B' may expand into the corresponding adjacent chambers 5A' and 5B'. Figure 5 The expansion of membranes 4A' and 4B' into their respective chambers 5A' and 5B' is exemplarily shown by dashed lines. To resist the expansion of membranes 4A' and 4B' into their respective chambers 5A' and 5B', pressure is also applied to membranes 4A' and 4B' in this design of device 1', particularly by means of the working medium in their respective chambers 5A' and 5B'. This pressure application can be, in particular, as described above, applying pressure and / or temperature to membranes 4A' and 4B' using the working medium in their respective chambers 5A' and 5B'. Here, the pressure applied to membranes 4A' and 4B' must be at least equal to, and preferably greater than, the pressure at which their respective membranes 4A' and 4B' expand towards their respective adjacent chambers 5A' and 5B'. Membranes 4A' and 4B' can be pressured independently of each other or uniformly. By applying pressure to membranes 4A' and 4B', a corresponding expansion force F is generated along the membrane surface of their respective membranes 4A' and 4B'. A .

[0083] As already described for the first design scheme of device 1, due to the expansion force F A The corresponding membranes 4A' and 4B' resist the corresponding frictional force F RThe movement passes through the seal. A corresponding frictional force F acts along the membrane surfaces of the respective membranes 4A' and 4B', resisting the friction between the respective membranes 4A' and 4B' and the corresponding seal 16'. R The sum of the forces acting adjacent to the corresponding seal 16' must preferably be greater than the corresponding frictional force F between the corresponding membranes 4A', 4B' and the corresponding seal 16'. R It can be specified here that the total force may be different or the same for each membrane 4A', 4B'. Furthermore, the expansion force F adjacent to the corresponding seal... A Each membrane 4A', 4B' can be of different or the same size. Similarly, pretension can be applied to the respective membranes 4A', 4B' by means of a corresponding device 18' for changing the pretension, and the direction of application is the same as the corresponding expansion force F. A The same preload F v Each membrane 4A' and 4B' can be of different or the same size. The expansion force F of the adjacent seal 16... A and the direction of action of the expansion force F A The same preload F v The sum can be of different or the same size for each membrane 4A', 4B'. Similarly, the sealing force F D The changes can be made independently or uniformly for each membrane 4A', 4B' by means of the device 17 for changing the sealing force.

[0084] Explanation of reference numerals in the attached figures

[0085] 1、1´: Equipment

[0086] 2, 2': First (upper) compression tool

[0087] 3, 3': Second (lower) compression tool

[0088] 4, 4A', 4B': Membrane

[0089] 5, 5A', 5B': Chambers

[0090] 6, 6': Channel

[0091] 7, 7': Hole

[0092] 8, 8': Working chamber

[0093] 8A: Notch

[0094] 9, 9': Guide component

[0095] 9A, 9A': Protrusion

[0096] 9B, 9B': Notch

[0097] 10: Edge elements

[0098] 11、11´: Gap

[0099] 12, 12´: Cavity

[0100] 13, 13': Clamping device

[0101] 14, 14': Pull-up bar

[0102] 15, 15': Spring

[0103] 16, 16'; Seals

[0104] 17, 17': Devices used to change the sealing force

[0105] 18, 18': Devices for changing preload

[0106] 19, 19', 19A'; workpiece

[0107] 20´: Core

[0108] F A Expansion force

[0109] F D Sealing force

[0110] F R Friction

[0111] F v Preload

Claims

1. A method for manufacturing a molded part, comprising the following steps: a) Providing equipment (1, 1'), said equipment comprising: First compression tool (2, 2'). Second compression tool (3, 3'). At least one membrane (4, 4A', 4B'), and At least one seal (16, 16'). The first pressing tool (2, 2') and the second pressing tool (3, 3') are capable of moving relative to each other between the open and closed positions. Among them, a working cavity (8, 8') for the workpiece (19, 19', 19A') is constructed between the first pressing tool (2, 2') and the second pressing tool. The membranes (4, 4A', 4B') are arranged at least in sections between the first pressing tool (2, 2') and the second pressing tool (3, 3'). The membranes (4, 4A', 4B') are arranged at least in sections within the working chambers (8, 8'). Wherein, at least one chamber (5, 5A', 5B') for the working medium is constructed between the membrane (4, 4A', 4B') and the first pressing tool (2, 2') and / or the second pressing tool (3, 3') in at least the closed position. The chambers (5, 5A', 5B') are at least sectionally sealed by the seals (16, 16') at least in the closed position. In order to seal the chambers (5, 5A', 5B'), the sealing force (F) can be reduced by means of the sealing elements (16, 16'). D ) is applied to the membranes (4, 4A', 4B'), and The membranes (4, 4A', 4B') and the first pressing tool (2, 2') and / or the second pressing tool (3, 3') have different coefficients of thermal expansion. b) The sealing force (F) is applied by means of the seal (16, 16'). D ) is applied to the membranes (4, 4A', 4B'), This involves using the sealing force (F) D An abutment is applied to the membranes (4, 4A', 4B'), and the chambers (5, 5A', 5B') are at least sectionally sealed, and Among them, through sealing force (F) D A frictional force (F) is applied between the membrane (4, 4A', 4B') and the seal (16, 16'). R ), c) Apply pressure and / or temperature to the membranes (4, 4A', 4B'), The membranes (4, 4A', 4B') expand in at least a segmental manner within the working chambers (8, 8'). Pressure is applied to the membranes (4, 4A', 4B'). The pressure resists the expansion of the membranes (4, 4A', 4B') into the chambers (5, 5A', 5B') and thereby causes an expansion force (F) along the membrane surface. A ),and Wherein, the expansion force (F) A At least adjacent to the seal (16, 16'), it resists the frictional force (F) between the membrane (4, 4A', 4B') and the seal (16, 16'). R ), Its features are, The membranes (4, 4A', 4B') are movable through the seals (16, 16'), and in step c), the membranes (4, 4A', 4B') are affected by the expansion force (F). A And at least in sections, it moves through the seal (16, 16').

2. The method for manufacturing molded parts according to claim 1, characterized in that, Pressure and / or temperature are applied to the membranes (4, 4A', 4B') using the working medium in the chambers (5, 5A', 5B').

3. The method for manufacturing molded parts according to claim 1, characterized in that, The membranes (4, 4A', 4B') expand at least segmentally within the working chambers (8, 8') to a greater extent than the first pressing tool (2, 2') and / or the second pressing tool (3, 3').

4. The method for manufacturing molded parts according to claim 1, characterized in that, Steps b) and c) overlap at least in time.

5. The method for manufacturing molded parts according to claim 1, characterized in that, The expansion force (F) A The frictional force (F) between the membranes (4, 4A', 4B') and the seals (16, 16') is greater than that between the membranes (4, 4A', 4B') and the seals (16, 16'). R ).

6. The method for manufacturing a molded part according to claim 1, comprising the following steps performed after step a): a1) Provide at least one workpiece (19, 19', 19A'). a2) Place the workpieces (19, 19', 19A') into the device (1, 1'), and a3) Move the first compression tool (2, 2') and / or the second compression tool (3, 3') to the closed position.

7. The method for manufacturing a molded part according to claim 6, wherein steps a1) to a3) are performed before step b) and / or before step c).

8. The method for manufacturing molded parts according to claim 1, characterized in that, The device (1, 1') provided in step a) includes at least one device (18, 18') for changing the pre-tightness of the membrane (4, 4A', 4B').

9. The method for manufacturing a molded part according to claim 8, comprising the following steps performed after step a): a4) Using a device (18, 18') for changing the pretension, a pretensioning membrane (4, 4A', 4B') is used.

10. The method for manufacturing a molded part according to claim 9, wherein step a4) is performed before step b) and / or before step c).

11. The method for manufacturing molded parts according to claim 9, characterized in that, By pre-tightening the membranes (4, 4A', 4B') according to step a4), a pre-tightening force (F) is applied to the membranes (4, 4A', 4B'). V ).

12. The method for manufacturing molded parts according to claim 11, characterized in that, The preload force (FV) is less than the frictional force (FR) between the membrane (4, 4A', 4B') and the seal (16, 16') during step b) and / or step c).

13. The method for manufacturing molded parts according to claim 11, characterized in that, During step b) and / or step c), the preload force (F) applied to the membranes (4, 4A', 4B') is changed by means of the device (18, 18') for changing the preload. V ).

14. The method for manufacturing molded parts according to claim 11, characterized in that, Expansion force (F) A ) and preload (F) V The sum of the forces during step b) and / or step c) is greater than the frictional force (F) between the membrane (4, 4A', 4B') and the seal (16, 16'). R ).

15. The method for manufacturing molded parts according to claim 1, characterized in that, During step b) and / or during step c), the pressure and / or temperature of the working medium in the chambers (5, 5A', 5B') are changed.

16. The method for manufacturing molded parts according to claim 1, characterized in that, The device (1, 1') provided in step a) includes at least one device (17, 17') for changing the sealing force.

17. The method for manufacturing molded parts according to claim 16, characterized in that, The at least one device (17, 17') is adjacent to the seal (16, 16').

18. The method for manufacturing molded parts according to claim 1, characterized in that, The device (1') provided in step a) includes at least one second membrane (4B'). Wherein, at least one second chamber (5B') for the working medium is constructed in the closed position between the at least one second membrane (4B') and the first pressing tool (2') and / or the second pressing tool (3'). In order to seal the second chamber (5B'), the sealing force (F) D It can be applied to the second membrane (4B') by means of at least one second seal (16'), and The second membrane (4B') is movable through the second seal (16').

19. The method for manufacturing molded parts according to claim 1, characterized in that, In step b) and / or step c), the pressure of the working medium in the chambers (5, 5A', 5B') is increased to 1.2 bar or to 2 bar.

20. The method for manufacturing a molded part according to claim 19, characterized in that... In step b) and / or step c), the pressure of the working medium in the chambers (5, 5A', 5B') is increased to a maximum range between 10 bar and 50 bar.

21. The method for manufacturing molded parts according to claim 20, characterized in that... In step b) and / or step c), the pressure of the working medium in the chambers (5, 5A', 5B') is increased to a maximum range between 15 bar and 30 bar.

22. The method for manufacturing molded parts according to claim 1, characterized in that, In step b) and / or step c), the temperature of the working medium located in the chambers (5, 5A', 5B') is increased to a range between 280°C and 500°C.

23. The method for manufacturing molded parts according to claim 22, characterized in that, In step b) and / or step c), the temperature of the working medium located in the chambers (5, 5A', 5B') is increased to a maximum range between 310°C and 410°C.

24. The method for manufacturing a molded part according to claim 1, comprising the following steps performed after step b) and / or after step c): c) Open the device (1, 1') and remove the workpiece (19, 19', 19A').

25. The method for manufacturing molded parts according to claim 1, characterized in that, Molded parts are molded parts made of fiber composite materials.

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