A METHOD FOR PRODUCING A REINFORCEMENT SECTION IN A WORKPIECE

Abstract

The invention relates to a method for producing a reinforcement section in a preferably plate-shaped workpiece, wherein the workpiece has a core layer, a first cover layer and a second cover layer. In particular, such a workpiece may be a lightweight building board. Provision is made therein for a pasty, thermosetting mass to be introduced into an opening by way of the nozzle, while the nozzle and/or the workpiece moves at least temporarily during the release of the mass.

Claims

1. A method for producing a reinforcement section in a workpiece, wherein the workpiece has a core layer, a first cover layer and a second cover layer the method comprises the steps of: creating an opening in the workpiece, wherein the opening extends through the first cover layer and into the core layer, moving a nozzle to the opening, and releasing a pasty, thermosetting mass into the opening by way of the nozzle, while the nozzle and/or the workpiece moves at least temporarily during the release of the mass.

2. The method according to claim 1, wherein the core layer has a honeycomb structure, of foam material, wherein the foam material can be a plastic foam such as polystyrene rigid foam, wood foam, metal foam such as aluminium foam, paper, cardboard or one or more timber struts.

3. The method according to claim 1, wherein the nozzle is guided in a translational and/or rotational movement during the release of the mass.

4. The method according to claim 1, wherein a mould element is introduced into the pasty mass prior to the hardening thereof, so as to form a thread or an opening following the removal of the mould element.

5. The method according to claim 1, wherein the pasty mass is fed to the nozzle by way of an extruder or a pump system.

6. The method according to claim 1, wherein the opening is made through the core layer and partially into the second cover layer.

7. The method according to claim 1, wherein the nozzle is introduced into the opening before the pasty mass is released by way of the nozzle.

8. The method according to claim 1, wherein the volume of the pasty mass that is introduced into the opening by way of the nozzle is greater than the volume defined by the opening.

9. The method according to claim 1, wherein the pasty mass is a thermoplastic mass which becomes pasty when heated and which hardens when it cools, or the pasty mass is a UV-curing mass.

10. The method according to claim 1, wherein the pasty mass forms a form-fitting connection with the workpiece following the hardening thereof.

11. The method according to claim 1, wherein the pasty mass is introduced into a side region of the opening.

12. The method according to claim 1, wherein when viewed from above, the opening is made in the workpiece in a linear manner.

13. The method according to claim 12, wherein the linear opening surrounds a workpiece region which is removed following the hardening of the pasty mass in the opening.

14. The method according to claim 1, wherein the method is carried out by a machining device, and wherein the workpiece is held in a single clamping operation.

15. A furniture element having a core layer, a first cover layer and a second cover layer, wherein a reinforcement section is introduced in layers through one of the cover layers and into the core layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1 shows a schematic representation of a first embodiment of the invention.

[0032] FIG. 2 shows a schematic representation of a second embodiment of the invention.

[0033] FIG. 3 shows a third embodiment of a method according to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] In the following, the invention will be described in more detail on the basis of a plurality of embodiments and with the help of the enclosed drawings. Modifications described within the scope of the embodiments can be combined in order to form further embodiments of the invention.

[0035] FIG. 1 shows a schematic view of a workpiece W. The workpiece has a core layer 10, a first cover layer 11 and a second cover layer 12. In particular, the workpiece W is a lightweight building board, wherein the core layer 10 has a lower density than the material of the first and/or second cover layers 11, 12. In particular, the core layer 10 is made of a foam material, such as a polystyrene rigid foam, while the cover layers are made of a plywood material.

[0036] In the representation according to FIG. 1, a bore (opening) 15 formed as a blind bore has already been made in the workpiece W. The bore 15 is made using a milling head or a drilling head, for example, such that the first cover layer 11 and the core layer 10 are penetrated. Moreover, in the embodiment example the drilling head or milling tool also enters the second cover layer 12, but does not penetrate it.

[0037] Subsequently, a nozzle 20 is introduced to the workpiece W. This nozzle 20 is connected to an extruder (not shown) that conveys a pasty, thermosetting mass to the nozzle 20. The nozzle 20 is provided with one or more openings for discharging the pasty, thermosetting mass 21.

[0038] In the present embodiment example, the pasty mass is an extruded thermoplastic material which is discharged from the nozzle 20 at an injection temperature of approximately 220 C.

[0039] The thermoplastic material is introduced into the bore (opening) 15 to form a reinforcement section, while the nozzle 20 and the workpiece W are moved relative to one another. In particular, the workpiece W is kept stationary while the nozzle is guided in a translational or rotational movement relative to the workpiece W.

[0040] In the embodiment shown in FIG. 1, the nozzle 20 is guided in a circular movement in a plane parallel to the surface of the workpiece W formed by the first cover layer 11. During this movement of the nozzle 20, the thermoplastic material is continuously discharged and therefore the bore (opening) 15 is gradually filled with the thermoplastic material in the side region or in its entirety.

[0041] Since in the present case the core layer 10 is a polystyrene rigid foam, the thermoplastic mass introduced fuses in part to the core layer 10 such that the thermoplastic mass displaces the core layer or penetrates into it. However, since the nozzle 20 moves relative to the workpiece W, the thermoplastic mass is prevented from penetrating too far into the core layer. Instead, the bore 15 is filled by the application of the pasty mass in layers.

[0042] Since the bore 15 has been made in the workpiece W in such a way that the bore 15 extends into the second cover layer 12, the pasty mass provides an anchoring between the first and second cover layers 11, 12.

[0043] Once the pasty, thermosetting mass 21 has been introduced into the bore 15, the mass can harden according to a first variant. Subsequently, an opening is made in the hardened mass using a drill. Alternatively, according to a further variant it is possible to introduce a thread into the hardened mass. In this way, a contact point for a screw or similar can be created.

[0044] According to a modification it is possible to introduce or press into the still pasty mass an engagement element, such as a screw, such that the screw serves as a negative mould, wherein a thread remains in the reinforcement section once the pasty mass has hardened and the screw has been unscrewed.

[0045] FIG. 2 shows a second embodiment of the invention. The second embodiment essentially differs from the first embodiment in that the opening 15 has a smaller diameter than the opening 15 of the first embodiment.

[0046] The nozzle 20, which has already been described with respect to the first embodiment, is used to introduce the pasty, thermosetting mass 21. However, according to the second embodiment, the nozzle 20 moves in a translational direction during the introduction of the pasty, thermosetting mass.

[0047] In particular, the nozzle 20 is first of all brought into the region of the workpiece W in such a way that the nozzle 20 extends at least in part into the opening 15 (movement in direction Y1). Then, the introduction of the pasty mass 21 begins, and during the introduction of the pasty mass 21 the nozzle 20 continuously or gradually moves out of the opening 15 and away from the workpiece W (direction of movement Y2). In this way, the pasty mass is introduced into the opening 15 in layers.

[0048] FIG. 3 shows a third embodiment of the method according to the invention within the scope of a plurality of successive machining steps. A workpiece W is machined in the same way as or in a similar manner to the embodiments described above. With regard to the details of the workpiece W, reference is made to the statements made above.

[0049] Once the workpiece W has been provided in machining step A, an opening 15 which is circular when viewed from above is made in the workpiece W in a subsequent machining step B. When viewed from above, the circular opening 15 surrounds a workpiece region K. As in the embodiments described above, the opening 15 is formed as a blind bore and therefore does not penetrate the lower cover layer of the workpiece W.

[0050] In a further machining step C, the pasty mass 21 is now introduced into the opening 15 by way of the nozzle (not shown) and the opening 15 is completely filled with the pasty, thermosetting mass 21. Moreover, the thermosetting mass 21 protrudes over the upper cover layer of the workpiece W, such that a complete filling of the opening 15 is ensured.

[0051] Subsequently, the mass 21 protruding over the opening 15 which at this point has already hardened is removed (machining step D in FIG. 3). For this, a milling tool, for example, is used, as one possible finishing step, wherein the milling tool is guided along the contour of the opening 15. In this connection it is preferred that the milling tool is used that is also used for making the opening 15. In this way, the milling tool can be guided along the same path that was also used to make the opening 15. Since the milling tool therefore has a diameter corresponding to the width of the opening 15, it is possible to remove the protruding hardened mass in such a way that it is flush with the upper cover layer.

[0052] As an alternative to the aforementioned machining step using a milling tool or similar to finish the hardened mass, provision can be made for the not yet completely hardened mass to have pressure applied to it by an object such as a plate or a roll, such that the upper side of the mass is flush with the upper side of the workpiece. As a result of the pressure exerted, the mass will be pushed further into the core layer. In this way, the surface of the mass is flattened, such that a surface of high quality is provided.

[0053] This process is performed once a final layer has been applied that partially protrudes over the upper side of the workpiece. If a roll is used, for example, it is guided over the filled opening.

[0054] If the object used is a metal plate or a metal role, it is possible to dissipate the heat from the not yet completely hardened pasty mass by way of the thermally conductive material.

[0055] In a further machining step E, the internal workpiece region K is now removed, wherein a milling tool can also be used for this. During this machining step, the milling tool used here may come into contact with a side portion of the hardened mass 21, such that it is ensured that the core layer is completely removed within the contour defined by the hardened mass 21.

[0056] Within the scope of method step E provision can be made for the lower cover layer of the workpiece W to remain in place. Alternatively, it is also possible to remove the lower cover layer within the scope of method step E.

[0057] It is therefore possible using the method shown in FIG. 3 to provide the core layer of the workpiece W with a side seal, such that the core layer is protected from its surroundings in spite of the opening that has been formed. In this way, the ingress of moisture into the core layer can be prevented, for example. Furthermore, one or more attachment points can be provided on the hardened mass.

[0058] According to a further embodiment that is not shown, provision is made for a bearing material to be introduced into the opening, with the help of which pieces of furniture can easily slide on individual profiles, for example. In particular, this is a plastic sliding bearing. Folding furniture, the component parts of which can slide on a rail or a bearing, is advantageous particularly in the lightweight sector. A bearing introduced in this way can be made in special sizes and can be custom-made. As an example, such a bearing may be a guide in a sliding door.