DE102006049180B4 - Method for producing a one-part thermoset body - Google Patents

Abstract

A method for producing a one-piece body (10) with a cavity (14) from at least one molding material (18) which is reshaped by means of a reshaping press tool (12) to form a cured, thermosetting body (10), characterized in that for the formation of the Cavity (14) a core element (16) is suitably arranged in the molding material (18) within the forming press tool (12) with mold shells (24, 26), and a lower mold shell (26) is used, which has a plurality of ribs (30 ) and between the mold shells (24, 26) in the region of the ribs (30) appropriately designed spacers (34) are attached to the upper mold shell (24) so that during the forming process of the ribs (30) there is no direct contact between them and the upper one Molding shell (24) can occur.

Description

The invention relates to a method for producing a one-piece body of at least one molding material, which is formed by means of a Umformpresswerkzeugs to form a cured, thermoset body, as well as series body elements available therefrom.

Method of the type mentioned are known. For example, the DE 102 19 276 A1 a device for extracting a finished pressed, in particular made of thermoset workpiece from a press tool and for removing the workpiece from the molding press.

From the US 6713008 B1 discloses a method for producing a composite structure in sandwich construction, which is composed of three superimposed resin-impregnated fabric layers. The core layer has a wave-like structure, wherein the wave troughs rest on the lower fabric layer and the wave crests on the upper fabric layer, respectively.

It is an object of the invention to provide a flexible method for producing a one-piece Duroplastkörpers.

The object is achieved by a method having the features of claim 1. The method according to the invention is characterized in that the body is a hollow body with a cavity, wherein a core element in the molding material within the forming die is suitably arranged to form the cavity. In this case, the lower mold shell has a plurality of internally arranged ribs and there are fastened between the mold shells in the region of the ribs correspondingly formed spacers on the upper mold shell, so that during the Umformpressvorgang the ribs no direct investment contact thereof may occur with the upper mold shell.

By means of the method it is now possible to transform a thermosetting molding material by means of a forming press tool utilizing a curing process such that a one-piece hollow body can be produced with a cavity. In traditional hollow body manufacturing processes, only individual body parts are produced from a thermosetting molding material by means of a forming press tool and then joined together, for example, by means of a rivet, screw or adhesive connection. This traditional method for producing a hollow body is relatively complicated and expensive to manufacture.

The hollow body can be produced by means of the forming press tool in a single Umformpressvorgang. In this case, it is possible that the forming process and the curing process are separated from each other or occur almost simultaneously.

The hollow body may consist of different duroplastic molding materials. The different molding materials may possibly fulfill different functions, eg. B. a carrier function in a strength-relevant area of the hollow body or an aesthetic function on a visible side of the hollow body.

The molding material may consist of at least one raw element before curing and in particular of two separate raw elements. Furthermore, the raw element prior to curing may consist of a molding compound, which is in particular mat-shaped. The molding composition may, for. As an SMC (Sheet Molding Compound), which is in particular mat-shaped. Optionally, the raw element may also be formed as a flat blank element. Such raw elements are known per se, whereby they can be used by means of the method particularly flexible for the production of a hollow body. The molding material may be, for example, a fiber composite material.

According to a possible embodiment, the body is designed as a multi-shell body with shell molds, which are connected to one another cohesively along its circumference. The method now advantageously allows producing a multi-shell hollow body within the scope of a single forming press operation. In this case, the body along its entire circumference or only along part of its circumference may contain cohesively connected shell molds.

The curing of the molding material within the forming press tool can be carried out under increased operating pressure and / or under increased operating temperature. In this case, the curing process of the molding material is known per se.

The core element may be formed as a separate functional element and possibly consist of a soluble core material or of a fusible core material or of a decomposable core material. Thus, in each case suitable core elements can be provided depending on the manufacturing requirements of the hollow body, wherein the different core materials are known per se.

The body may be a substantially closed hollow body having at least one opening through which the cavity from the outside is accessible. In this case, the core element can be removed after the curing of the molding material from the body or possibly even remain in selbigem. The latter variant would also be z. B. possible with a completely closed hollow body.

According to a possible embodiment, the core element is a compressible core element and / or an expanding core element. The core element is possibly made of a porous core material. Thus, by means of the method, a very wide variety of hollow bodies can be produced, wherein the core element can be removed from the hollow body or optionally also remain in the same. The core element may optionally be used due to its expansion properties during the Umformpressverfahrens to achieve a sufficiently good dimensional accuracy of the hollow body.

According to a possible embodiment variant, the core element and / or the forming press tool can have a side with a geometric surface structuring and a side with a flat surface. Furthermore, the core element may include a plurality of spaced-apart core parts for producing a spatially structured cavity. The core element may be formed in one or more parts. In this case, a multipart core element consist of different core materials. Due to the possibility of a particularly flexible core design can be met in a relatively simple manner a variety of requirements for the process for producing hollow bodies of a thermosetting molding material by means of a suitable Umformpresswerkzeugs reproducible exactly.

The method is particularly suitable for producing a body that is a standard bodywork element for a vehicle. Due to the large number of bodies that can be produced by the process, it is possible to achieve considerable production costs and, in particular, relatively short production times for the corresponding bodies.

The forming press tool can have a stamp unit and a counterholder unit. In this case, the stamp unit and / or the counter-holder unit can be movable in at least one forming direction. In principle, other structural configurations of a forming press are conceivable.

Further advantages of the invention will become apparent from the description.

The invention will be explained in more detail with reference to several preferred embodiments with reference to a schematic drawing.

Showing:

1 a schematic perspective view of a forming press tool with two raw elements and a core element in an exploded view;

2 a schematic perspective view of a cut, re-molded body with core elements according to a first possible embodiment;

3 a schematic sectional view through a Umformgepressten body with core elements inside a Umformpresswerkzeugs according to a possible embodiment;

4 a schematic sectional view of a formed-molded body with core elements in a Umformpresswerkzeug according to a further alternative embodiment and

5 a schematic perspective view of a Umformgepreststen body with removed core.

1 shows a schematic exploded view of a forming press tool 12 consisting of an upper and a lower mold half, wherein the lower mold half is arranged fixed in position and the upper mold half according to double arrow 40 can be moved in the vertical direction relative to the lower mold half to perform a Umformpressvorgangs. Between the two tool halves is a molding material 18 consisting of two raw elements 20 . 22 between which a core element 16 is arranged. The raw elements 20 . 22 are designed as cut mats made of a fiber composite material. The tool halves contain at their contact side with the body to be produced a correspondingly adapted surface structuring.

To make a body 10 according to the 2 to 5 will the in 1 illustrated upper mold half according to double arrow 40 down to the raw elements 20 . 22 with interposed core 16 , which are carried by the lower mold half, moved and finally compressed to perform a Umformpressvorgangs, through which a body 10 with a cavity 14 is formed. The 2 to 4 show different embodiments of a producible by the method body 10 , The body 10 according to 2 is without forming press tool 12 shown and contains as a molding material 18 two bowls 24 . 26 , The upper mold shell 24 is formed as a flat plate, while the lower shell mold 26 as an outer flat plate with a plurality of internally disposed ribs 30 is trained. To form a corresponding cavity 14 between the shell molds 24 . 26 are suitable core elements 16 intended. Furthermore, between the shell molds 24 . 26 in the area of the ribs 30 appropriately trained spacers 34 on the upper mold shell 24 attached, so that during the Umformpressvorgang of the ribs 30 no direct contact with the same with the upper shell mold 24 can occur and thus an exact flatness of the outer surface of the upper shell mold 24 due to the interposed spacers 34 between the ribs 30 and the upper shell mold 24 is guaranteed. The core element 16 can as in the present embodiment according to 2 from a plurality of spaced-apart core parts 38 which, if appropriate, after completion of the Umformpressvorgangs from the body 10 can be removed to form a hollow body.

3 shows a schematic sectional view of one between two mold halves of a corresponding forming press tool 12 arranged body 10 after completion of the forming press operation according to a further alternative embodiment. In contrast to the embodiment of the body 10 of the 2 contains the body 10 of the 3 a trained as a flat sheet spacers 34 between the upper shell 24 and the ribs 30 or the corresponding flat surfaces 36 of the core element 16 or the core parts 38 , The spacer 34 also complies with the embodiment according to 3 in the area of the ribs 30 same function as the body 10 described above 2 , In contrast to the embodiment of the body 10 of the 2 are in the embodiment according to 3 the core parts 38 at its contact side with the lower shell mold 26 and the lower mold half of the forming press tool 12 with a geometric surface structuring 32 Mistake. The lower mold half of the forming press tool 12 is designed accordingly surface structured. In contrast, the contact surfaces of the core parts 38 and the mold shell 24 on the upper side of the body 10 just trained.

In 4 is another embodiment of a body 10 shown in a schematic sectional view. In contrast to the variant of the body 10 according to 3 is appropriate 4 the spacer 34 formed as a film, which in the region of the ribs 30 provided with reinforced foil wall areas. This serves in particular to an increased shielding of the upper shell mold 24 in front of the forming ribs 30 during the Umformpressvorgangs and thus ensures a precisely planar configuration of the outer surface of the upper shell mold 24 ,

5 shows a possible embodiment of a one-piece body 10 in the form of a hollow body of a thermosetting molding material 18 , The body 10 is as a multi-shell body with shell molds 24 . 26 formed, which are cohesively connected to each other along its circumference. Thus, it is the body 10 around a substantially closed hollow body with according to the present embodiment, two openings 28 through which the cavity 14 is accessible from the outside. The cavity 14 , which during the Umformpressvorgangs means of a correspondingly formed core element 16 (not in 5 shown) is, after completion of the Umformpressvorgangs due to the accessibility through the openings 28 removed from the interior of the hollow body exposing the cavity 14 of the body 10 , At the in 5 represented body 10 it is a standard bodywork element for a vehicle.

Claims (8)

Method for producing a one-piece body ( 10 ) with a cavity ( 14 ) of at least one molding material ( 18 ), which by means of a forming press tool ( 12 ) is formed to form a cured thermoset body ( 10 ), characterized in that to form the cavity ( 14 ) a core element ( 16 ) in the molding material ( 18 ) within the forming press tool ( 12 ) with shell molds ( 24 . 26 ) is arranged suitably, and a lower shell mold ( 26 ) is used, which has a plurality of internally disposed ribs ( 30 ) and between the shell molds ( 24 . 26 ) in the area of the ribs ( 30 ) correspondingly formed spacers ( 34 ) on the upper mold shell ( 24 ) are fixed, so that during the Umformpressvorgang the ribs ( 30 ) no direct contact of the same with the upper shell ( 24 ) can occur. Method according to claim 1, characterized in that the body ( 10 ) by means of the forming press tool ( 12 ) is produced in a single Umformpressvorgang. Method according to one of the preceding claims, characterized in that the molding material ( 18 ) before curing from at least one raw element and in particular from two separate raw elements ( 20 . 22 ) consists. Method according to claim 3, characterized in that the raw element ( 20 . 22 ) before the Curing consists of a molding material, which is in particular mat-shaped. Method according to claim 4, characterized in that the raw element ( 20 . 22 ) is designed as a flat blank element. Method according to one of the preceding claims, characterized in that the body ( 10 ) as a multi-shell body with shell molds ( 24 . 26 ) is formed, which are cohesively connected to each other along its circumference. Method according to one of the preceding claims, characterized in that the curing of the molding material ( 18 ) within the forming press tool ( 12 ) under increased operating pressure and / or under increased operating temperature. Method according to one of the preceding claims, characterized in that the core element ( 16 ) after curing of the molding material ( 18 ) from the body ( 10 ) Will get removed.

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