Method for manufacturing a lightweight component, in particular a body part

Abstract

The invention relates to a method for producing a lightweight component (22), which is formed from a metal sheet (16), a fiber fabric or fiber fabric embedded in a thermoplastic matrix (21) and a mass of fiber-reinforced plastic (20), in particular for Manufacture of a body part. Such a method has the following features according to the invention: - a mold (1), which has an upper mold part (2) and a lower mold part (3), is moved into an open position, - the metal sheet (16) is inserted and fixed from below into the temperature-controlled mold upper part (2), - The lower mold part (3) has projections (4) pointing upwards, the fiber-reinforced plastic (20), which is heated, being introduced between the projections (4), - The fiber fabric or fiber fabric, which is embedded in the thermoplastic matrix (21), is heated and draped onto the projections (4), - The mold (1) is moved to a closed position, during the pressing of the fiber fabric or fiber fabric that is embedded in the thermoplastic matrix (21) and the formation of a structure (23) from the glass fiber reinforced plastic (20) that is between the fiber fabric or Fiber fabric, which is embedded in the thermoplastic matrix (21) and the lower mold part (3) is arranged.

Description

[0001] The invention relates to a method for manufacturing a lightweight component formed from a metal sheet, a woven fiber fabric or a woven fiber mat embedded in a thermoplastic polymer matrix, and a fiber-reinforced plastic. In particular, the invention relates to a method for manufacturing a body panel, which is designed especially as a longitudinal or transverse beam or a vertically extending column.

[0002] A fibrous fabric or woven material embedded in a thermoplastic polymer matrix is ​​also known as an organosheet.

[0003] A process of the type mentioned above is known from DE 10 2009 042 272 A1. To produce the lightweight component, a metal sheet is first inserted from above into a lower mold part. The heated organosheet is then applied to the metal sheet. Extruded fiber-reinforced plastic is then arranged on the heated organosheet. Finally, the upper mold part is placed on top, and the two mold parts are pressed together, thus closing the mold. The result is a lightweight component, in particular a body panel, formed from a metal sheet with a plastic reinforcement structure. The metal sheet is bonded to the plastic reinforcement layer, i.e., the organosheet. This reinforcement layer is, in turn, bonded to the plastic reinforcement structure.

[0004] The object of the present invention is to provide an alternative method for manufacturing a lightweight component consisting of a metal sheet, a fiber fabric or woven fabric embedded in a thermoplastic matrix, and a fiber-reinforced plastic. The method should enable the lightweight component to be manufactured in a single pressing operation, thereby avoiding process disadvantages, particularly the critical temperature-time management, and improving the positioning accuracy of the components.

[0005] The problem is solved by a method that has the features of claim 1.

[0006] The inventive method uses a mold comprising an upper and a lower mold part. This mold is first moved into an open position. A metal sheet is then inserted from below into the heated upper mold part and secured. This securing can be achieved in various ways, for example, by magnets or mechanical clamps. The lower mold part has upward-facing projections. Heated fiber-reinforced plastic is placed between these projections. The heated fiber fabric or woven material, embedded in the thermoplastic matrix, the organosheet, is then laid and draped onto the projections.In particular, the heated, laid-down organosheet is draped in one direction and then shaped in a second direction by elements not shown, which drape areas of the organosheet extending beyond the projections into the desired shape. The mold is then moved into the closed position. This involves compressing the fiber fabric or fiber layup embedded in the thermoplastic matrix and forming a structure from the fiber-reinforced plastic located between the fiber fabric or fiber layup embedded in the thermoplastic matrix and the mold base.When the mold closes, the flow of fiber-reinforced plastic presses the organosheet into the corresponding contour of the metal sheet, forming the structure of the lightweight component from the fiber-reinforced plastic according to the geometry of the mold base. The fiber-reinforced plastic is, in particular, a glass-reinforced plastic. The structure serves primarily to reinforce the lightweight component.

[0007] Thus, it is possible to produce the lightweight component in a single pressing process, with the one-time closing of the mold.

[0008] Preferably, the lightweight component is manufactured through the interaction of the metal sheet with an associated transmitter layer. The transmitter layer is preferably assigned to the side of the metal sheet, which is fixed in the upper mold part, facing the lower mold part. This layer can be arranged in various ways or integrated into the manufacturing process. For example, the metal sheet can be coated with the transmitter layer before being inserted into the upper mold part. According to another preferred alternative, the transmitter layer is inserted into the metal sheet as a preform. In yet another preferred alternative, the transmitter layer is arranged as a stretched film between the metal sheet and the fiber fabric or fiber layup embedded in the thermoplastic polymer matrix.

[0009] The method is preferably used with a mold that has a top mold part designed as a die and a bottom mold part designed as a male die. The top mold part is thus negatively shaped, while the bottom mold part is positively shaped.

[0010] The projections used in the mold base serve primarily to hold the heated fiber-reinforced plastic between them and to lay the heated fiber fabric or fiber layup, embedded in the thermoplastic matrix—thus forming the organosheet—on the projections, draping it in place. These projections, especially thin and therefore delicate ones, prevent close contact with the relatively cold mold and thus prevent premature cooling of the heated and inserted materials before the actual pressing process. For the subsequent pressing process to produce the lightweight component, it is essential to ensure that both the organosheet and the fiber-reinforced plastic have reached a sufficiently high temperature.This ensures that the thermoplastic materials bond intimately, or that the fiber-reinforced plastic has sufficient flowability to fill the structure (e.g., ribs), and that the transmitter layer is exposed to a sufficient temperature to melt, react, harden, and develop its necessary properties. The transmitter layer has a considerable thickness, preferably in the range of 0.1 mm to 0.3 mm. It is therefore significantly thicker than an adhesion promoter (primer) and serves a different function. Maintaining tool integrity and ensuring high quality of the lightweight components are further linked to adhering to a time- and temperature-critical process during the feeding of these components. The locally required amount of fiber-reinforced plastic depends on the local volume requirement in the mold for forming the structure. The organosheet, on the other hand, must be draped spatially before the pressing process.In principle, draping is possible through the weight of the organosheet and the subsequent closing process of the mold.

[0011] The upward-facing projections can be designed in various ways to receive and drape the heated organosheet. Preferably, the upward-facing projections are formed directly by the lower mold part. This results in a simple and stable construction of the mold in the area of ​​the lower mold part. Contact surfaces between the cold lower mold part and the heated fiber-reinforced plastic, as well as the heated organosheet, are thus minimized. Alternatively, the upward-facing projections can be mounted in a die of the lower mold part so that they can be extended and retracted. While the forming process is carried out by means of the die of the lower mold part and the upper mold part, the upward-facing projections, which are mounted in the die so that they can be extended and retracted, serve to receive the fiber-reinforced plastic and to deposit the organosheet.During the closing of the mold, and thus during the production of the lightweight component, the projections stored in the punch retract.

[0012] According to a particularly advantageous embodiment, during the production of the lightweight component, a sealing frame movable along the lower mold section contacts the underside of the metal sheet in the area of ​​its circumferential edge before the mold is closed, sealing it against an interior area of ​​the metal sheet. This sealing frame also holds the previously draped organosheet in its shape. This ensures that neither thermoplastic material nor organosheet can be present in the area of ​​the metal sheet's circumferential edge during the manufacturing process. This exclusively metallic edge area of ​​the lightweight component allows for straightforward connection of the lightweight component to adjacent components, in particular, contact between this metallic area of ​​the lightweight component and neighboring metallic components during the subsequent vehicle production process.When the tool closes, the sealing frame retracts into the lower part of the tool, reducing the space containing the organosheet and the fiber-reinforced plastic. The increasing pressure then forces the plastic into the cavity, forming the reinforcing plastic structure.

[0013] Further features of the invention will become apparent from the dependent claims, the accompanying drawing and the description of the preferred embodiments of the method according to the invention shown in the drawing, without being limited thereto.

[0014] It shows:

[0015] Fig. 1 a forming tool according to a first embodiment, for carrying out the method according to the invention, illustrated in a sectional view of the forming tool,

[0016] Fig. 2 to Fig. 8 process sequences with the forming tool according to Fig. 1 for the manufacture of a lightweight component, in particular a body part,

[0017] Fig. 9 a variant regarding Fig. 2, concerning the arrangement of metal sheet and transmitter layer,

[0018] Fig. 10 a forming tool according to a second embodiment, for carrying out the method according to the invention, illustrated in a sectional view of the forming tool,

[0019] Fig. 11 to Fig. 15 process sequences with the forming tool according to Fig. 10 for the production of a lightweight component, made of sheet metal, fiber-reinforced plastic and organosheet. Character description

[0020] Fig. Figure 1 shows a forming tool 1 For manufacturing a lightweight component, in particular a body panel of a motor vehicle. This body panel is, for example, a B-pillar of a passenger car. The mold 1is shown in a sectional view, cut perpendicular to the longitudinal extent of the B-pillar. Accordingly, the forming tool extends over a relatively large length perpendicular to the plane of the drawing. Fig. 1.

[0021] The forming tool 1 features a shaped upper 2 and a mold base 3 up. The forming tool 1 is in Fig. 1 shown in fully open position. The upper part of the mold 2 is called a matrix, the mold base 3 trained as a matrix.

[0022] The lower part of the mold 3 has upward-pointing protrusions 4 in the exemplary embodiment according to Fig. 1 the protrusions 4 not directly through the lower part of the mold 3 formed, but in a stamp 5 of the mold base 3 stored. Specifically, the upward-facing protrusions are 4 in the stamp5 Mounted in a retractable and extendable position. In the initial state according to Fig. 1 are the protrusions 4 completely within the stamp 5 The advantages 4 are in a common bearing plate 6 stored so that the protrusions 4 when the bearing plate is subjected to pressure 6 They can be extended and retracted synchronously.

[0023] The upper part 2 has a depression 7 and the stamp 5 one regarding the deepening 7 complementary increase 8 The difference in geometry forms the cavity in which the lightweight component to be manufactured is placed. In the area of ​​the increase 8 is the stamp 5 with cutouts 9 Provided for the rib and reinforcement geometry. Correlated with the recesses. 9 prevail 4 the drillings 10 in the stamp 5 .

[0024] Due to the longitudinal extent of the mold 1 , thus the extension of the forming tool 1 Perpendicular to the plane of the leaf, a multitude of projections pierce through. 4 corresponding drill holes 10 in the stamp 5 , which are connected to the common bearing plate 6 are connected. Thus, there is a difference between the arrangement of projections. 4 a canal extending perpendicular to the plane of the leaf 11 (see Fig. 2) formed when the projections 4 in their extended position.

[0025] On both sides of the rise 8 of the stamp 5 are in the stamp 5 , on the upper part of the mold 2 facing side, recessed area 12 , in particular grooves extending perpendicular to the plane of the sheet are provided. These accommodate a sealing frame. 13 a frame that can be extended and retracted. The sealing frame 13is on its upper form 2 far side in poles 14 stored, which in turn are in a common bearing plate 15 are stored. This bearing plate is controlled by the adjusting means. 15 can be actuated, so that the sealing frame 13 from the in Fig. 1 illustrated established position in which this is in the stamp 5 has been driven in, partly from the stamp 5 can be extended. The sealing frame 13 is arranged in such a way that, in its extended position, it lies in the area next to the recess 7 of the upper part of the mold 2 It can be sealed. A prerequisite for continuous openings in the lightweight component is openings in the metal sheet. 16 , which are sealed by spring-loaded sealing pistons, which in turn are linked to the movement of the sealing frame 13 are coupled.

[0026] The inventive method for manufacturing the lightweight component using the mold tool 1 according to the embodiment example Fig. 1. As can be seen from the presentation of the Fig. 2 to Fig. 8 illustrates as follows: How to Fig. As shown in 2, a metal sheet is inserted from below. 16 into the recess of the tempered mold top 2 inserted and fixed in the metal sheet. 16 Existing openings are preferably closed with thin sheets or plugs. Open openings are possible for creating undercuts or for realizing through openings in the lightweight component being manufactured. – The metal sheet is fixed in place. 16 for example, magnetic or via claws that are in the upper part of the mold 2 are planned. The deepening 7 is corresponding to the three-dimensional metal sheet 16shaped and indicates the depression 7 assigned section 17 adjacent flange sections 18 on. In the area of ​​the lower part of the mold. 3 The side facing is the metal sheet 16 with a transmitter layer 19 coated. The coating of the metal sheet 16 This is done, for example, by powder coating.

[0027] During the procedural section according to Fig. 2 are the protrusions 4 extended and the sealing frame remains 13 in its stamp 5 entrenched position.

[0028] Subsequently, as per the procedural section according to Fig. 3 illustrates, between the protrusions 4 mass 20 a mass made of fiber-reinforced, especially glass-fiber-reinforced, plastic, which is heated. 20is designed as a strand that extends perpendicular to the plane of the sheet over the length of the forming tool. 1 between the protrusions 4 positioned and thereby on the stamp 5 in the area of ​​the recess 9 is being released.

[0029] Then, according to the Fig. 4. Procedure section shown, applied to the upper, free ends of the projections 4 A fibrous fabric or fibrous layup embedded in a thermoplastic polymer matrix, hereinafter referred to as an organosheet. 21 labelled, heated and laid down.

[0030] For example, regarding the in the Fig. 3 and Fig. 4 process steps shown, the mass 20 made of fiber-reinforced plastic in portions along the length of the mold. 1 between the protrusions 4deposited or placed there directly via a robot-guided extruder nozzle. The depositing of the organosheet. 21 on the ledges 4 This is preferably done using a robot.

[0031] Then, as the Fig. As can be seen from 5, the hot and therefore malleable organosheet 21 spatially draped. The organosheet is used in this process. 21 firstly in the direction perpendicular to the plane of the leaf and then on its outer side over the projections 4 The standing area is deformed downwards, into the area between the protrusions. 4 and the sealing frame 13 .

[0032] Then, as if to Fig. Figure 6 illustrates the sealing frame 13 extended and overall, as to Fig. 7 shown, the stamp 5 together with the sealing frame 13 towards the upper part of the mold 2moved. This position guarantees that the organosheet, draped in two directions by a device not shown, is 21 is maintained in its form.

[0033] The further movement beyond the state illustrates Fig. 7, in which the sealing frame 13 the flange sections on the front side 18 of the metal sheet 16 contacted and thus towards the deepening 7 of the upper part of the mold 2 seals. During the subsequent rapid closing of the mold. 1 Fig. 7 to Fig. 8 The actual pressing process for forming the lightweight component takes place. 22 , in which both the sealing frame 13 as well as the protrusions 4 to be inserted and thus the pressing of sheet metal 16 with transmitter layer 19 , organosheet 21 and mass 20made of fiber-reinforced plastic to form a stamp 5 defined rib structure of the lightweight component 22 realize. A rib produced in this process is labeled with the reference numeral. 23 designated.

[0034] Due to the sealing function of the sealing frame 13 Is it possible to create lightweight components where the pressed plastic structure is interrupted, or the metal sheet? 16 This is achieved when the area remains free of plastic or where a sheet metal opening is required. This is accomplished by installing a spring-loaded sealing frame before the pressing process. 13 on the area of ​​the metal sheet that must be kept free of plastic 16 is set up.

[0035] After the pressing process Fig. 8. The opening of the forming tool closes. 1 on, into the position according to Fig. 1, in which the produced lightweight component 22 from the mold1 is removed. In the first phase of demolding, both the sealing frame and the sealing frame are removed. 13 as well as the protrusions 4 synchronous with the opening movement of the upper part 2 moved. After the lightweight component separates from the stamp 5 The sealing frame remains in position relative to the lower part, and only the projections 4 push the lightweight component into the position for final removal.

[0036] Fig. Figure 9 shows, with regard to the procedural section according to Fig. 2. A modification. This involves a metal sheet. 16 without coated transmitter layer 19 from below into the tempered upper part of the mold 2 inserted and secured. Then, underneath the metal sheet... 16 the transmitter layer 19 as a stretched film between the upper part of the mold 2 and mold base 3 ordered. The following procedural section follows according to Fig. 9 the procedural stages according to the Fig. 3 to Fig. 8, whereby when closing the forming tool 1 , as to the Fig. 7 and Fig. 8 shown, the transmitter layer 9 deformed and attached to the metal sheet 16 is laid. Basically, therefore, in the described procedures, the transmitter layer represents 19 Taking into account the increased temperature over time, sufficient adhesion between the metal sheet 16 and organosheet 21 secure.

[0037] While in the embodiment according to the Fig. 1 to Fig. 9 of the stamps 5 The embodiment, which is one-piece, is shown in the exemplary embodiment according to the Fig. 10 and the process steps relating to this embodiment according to the Fig. 11 to Fig. 15 a multi-part stamp 5 of the mold base 3 . With the embodiment according to the Fig. For simplicity, identical components are designated with the same reference numbers.

[0038] The forming tool 1 according to Fig. 10 indicates the lower part of the mold 3 a stamp 5 on, which has a central stamp part 24 and one outside this stamp part 24 arranged outer stamp part 25 exhibits the outer stamp part. 25 points out the protrusions 4 up. The two stamp parts 24 and 25 They can be moved independently of each other, thus in the direction of the upper part of the mold. 2 Exit and enter in the opposite direction.

[0039] In Fig. 10 is the one in the top part of the mold 2 metal sheet used 16 This has already been illustrated. For example, it is magnetically attached to the upper part of the mold. 2 held. Subsequently, as shown in the illustration in Fig. 11 can be seen, in the space between the projections 4 formed recess 9 , located above the central part of the stamp 24 is located the mass 20 made of fiber-reinforced plastic, in particular glass fiber-reinforced plastic. The mass 20 This will therefore be applied to the central part of the stamp 24 placed. This mass 20 It is applied in a heated state, as described in the first embodiment. The heated organosheet is then... 21 , as to Fig. 12 illustrates the protrusions 4 laid out and draped there. Then, according to Fig. 13, the sealing frame 13 , who placed the stamp between himself 5 absorbs, extends and against the transmitter layer 19 coated metal sheet 16 pressed. At those points where the sealing frame 13 the metal sheet 16with transmitter layer 19 If contacted, no connection of the organosheet occurs later. 21 with the metal sheet 16 . Subsequently, as shown in the illustration of the Fig. As can be seen from 14, the outer stamp part 25 extended, thus in pressing position against the upper part of the mold 2 moved, so that the organosheet 21 according to the contour of the metal sheet 16 is deformed. Finally, the central stamp part is deformed. 24 extended, whereby the mass 20 is pressed from fiber-reinforced plastic and is a lightweight component 22 is generated. This is achieved through the illustrated design of the central stamp part. 24 , part of the mass 20 made of fiber-reinforced plastic in a space between the central stamp part 24 and the outer stamp part 25 displaced, thereby by means of a part of the mass 20 the rib 23of the lightweight component 22 is generated. After completion of the in Fig. In the 15 illustrated pressing process, the mold is used. 1 reopened, thus the lower part of the mold 3 from the upper part of the mold 2 moved away. Then the lightweight component produced can be... 23 the forming tool 1 can be taken. Reference symbol list 1 forming tool 2 Form top 3 Mold base 4 lead 5 stamps 6 bearing plate 7. Further Study 8 increase 9 Exclusion 10 Drilling Channel 11 12 Recessed area / groove 13 sealing frames 14 bars 15 bearing plate 16 sheet metal Section 17 18 Flange section 19 Transmitter layer 20 Mass made of fiber-reinforced plastic 21 Organosheet 22 Lightweight component 23rd rib 24 Central stamp part 25 Outer stamp part QUOTES INCLUDED IN THE DESCRIPTION

[0040] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0041] DE 102009042272 A1

[0003]

Claims

[1] Method for manufacturing a lightweight component ( 22 ), which is made from a sheet of metal ( 16 ), a fibrous fabric or fibrous layup embedded in a thermoplastic polymer matrix ( 21 ) and a mass of fiber-reinforced plastic ( 20 ) is formed, in particular for the manufacture of a body part, characterized by the following features: – a forming tool ( 1 ), which is a molded top ( 2 ) and a mold base ( 3 ) is moved into an open position, – the sheet metal ( 16 ) is poured from below into the tempered upper part of the mold ( 2 ) inserted and fixed, – the lower part of the mold ( 3 ) has upward-pointing protrusions ( 4 ) on, with the projections between the ( 4 ) the fiber-reinforced plastic ( 20 ) is introduced, which is heated, – onto the ledges ( 4) is the fiber fabric or fiber layup that is embedded in the thermoplastic polymer matrix ( 21 ), heated, laid out and draped, – the forming tool ( 1 ) is moved into a closed position when pressing the fiber fabric or fiber layup that is embedded in the thermoplastic polymer matrix ( 21 ) and forming a structure ( 23 ) made from fiber-reinforced plastic ( 20 ), which is between the fiber fabric or fiber layup embedded in the thermoplastic polymer matrix ( 21 ) and the lower part of the mold ( 3 ) is arranged. [2] Method according to claim 1, wherein the upper part of the mold ( 2 ) fixed metal sheet ( 16 ), on whose lower part of the mold ( 3 ) facing side, a transmitter layer ( 19 ) is assigned. [3] Method according to claim 2, wherein the transmitter layer ( 19) has a thickness of at least 0.1 mm, in particular a thickness of 0.1 to 0.3 mm. [4] Method according to claim 2 or 3, wherein the metal sheet ( 16 ), before inserting into the top of the mold ( 2 ), with the transmitter layer ( 19 ) is coated. [5] Method according to claim 2 or 3, wherein the transmitter layer ( 19 ) as a preform in the metal sheet ( 16 ) will be used. [6] Method according to claim 2 or 3, wherein the transmitter layer ( 19 ) as a stretched film between the metal sheet ( 16 ) and the fiber fabric or fiber layup embedded in the thermoplastic polymer matrix ( 21 ). [7] Method according to any one of claims 1 to 6, wherein the upper part of the mold ( 2 ) a die and the mold base ( 3 ) forms a matrix. [8] Method according to any one of claims 1 to 7, wherein the upward-facing projections ( 4 ) directly through the lower part of the mold ( 3 ) are formed. [9] Method according to any one of claims 1 to 7, wherein in a stamp ( 5 ) of the mold base ( 3 ) the upward-pointing protrusions ( 4 ) are mounted in a retractable and extendable manner. [10] Method according to any one of claims 1 to 9, wherein a mold base ( 3 ) movable sealing frame ( 13 ) before closing the mold ( 1 ) the metal sheet ( 16 ) on its underside in the area of ​​a circumferential edge ( 18 ) contacted and to an interior area of ​​the metal sheet ( 16 ) seals. [11] Method according to claim 10, wherein the sealing frames ( 13 ) in the lower part of the mold ( 3) is extended to such an extent that the draped fiber fabric or fiber layup embedded in the thermoplastic polymer matrix is ​​held and is subsequently closed by the closing of the mold tool ( 1 ) a pressure chamber through the sealing of the sealing frame ( 13 ) to the press chamber with contact to the metal sheet ( 16 ) or the transmitter layer ( 19 ) is formed. [12] Method according to claim 10 or 11, wherein a device connected to the movement of the movable sealing frame ( 13 ) coupled, spring-loaded sealing piston is arranged in such a way that open areas in the metal sheet ( 16 ) are closed by sealing.