METHOD AND DEVICE FOR PRODUCING A HOLLOW BODY

Abstract

In a method for producing a hollow body, a hollow body wall is created, which delimits a hollow space and which has a hollow space side facing the hollow space and an outer side facing away from the hollow space. The hollow body wall is created in portions by constructing wall segments that are adjacent to one another. Following the construction of a wall segment, the constructed wall segment is processed on the hollow space side before a further wall segment is constructed adjacent to the constructed wall segment. A device for carrying out this method comprises a processing device, by means of which a wall segment constructed by a constructing device is processed on the hollow space side before a further wall segment can be constructed adjacent to the constructed wall segment by the constructing device.

Claims

1. A method for producing a hollow body (1), within the scope of which method a hollow body wall (3) is created, which delimits a hollow space (4) of the hollow body (1) and which has a hollow space side (5) facing the hollow space (4) and an outer side (6) facing away from the hollow space (4), the hollow body wall (3) being created in portions by constructing wall segments (2, 17, 18) that are adjacent to one another, wherein, following the construction of a wall segment (2, 17, 18), the constructed wall segment (2, 17, 18) is processed on the hollow space side (5), before a further wall segment (17, 18) is constructed adjacently to the constructed wall segment (2, 17, 18).

2. The method according to claim 1, wherein, following the construction of a wall segment (2, 17, 18), the constructed wall segment (2, 17, 18) is processed on the hollow space side (5) by removing material of the constructed wall segment (2, 17, 18) and/or by producing a covering and/or by changing material properties of the material of the constructed wall segment (2, 17, 18).

3. The method according to claim 1, wherein a wall segment (2, 17, 18) is constructed from a material that is plastic in a state for being worked and which cures following the state for being worked, by the wall segment (2, 17, 18) being constructed from the material in the state for being worked, and in that the constructed wall segment (2, 17, 18) is processed on the hollow space side (5) once the material has cured, before a further wall segment (17, 18) is constructed adjacently to the constructed wall segment (2, 17, 18).

4. The method according to claim 1, wherein a hollow body wall (3), which at least approximately completely surrounds the hollow space (4), is created in portions by constructing wall segments (2, 17, 18) that are adjacent to one another.

5. The method according to claim 1, wherein a hollow body wall (3), which has a curvature on the hollow space side (5) and/or on the outer side (6), is created in portions by constructing wall segments (2, 17, 18) that are adjacent to one another.

6. The method according to claim 1, wherein a wall segment (2, 17, 18) is constructed in layers from a plurality of material layers (7, 10) arranged one above the other and/or side by side.

7. The method according to claim 6, wherein the wall segment (2, 17, 18), after having been constructed in layers, is processed on the hollow space side (5) with the exception of the material layer (10 last constructed, before a further wall segment (17, 18) is constructed adjacently to the constructed wall segment (2, 17, 18).

8. The method according to claim 5, wherein a wall segment (2, 17, 18) is constructed in layers from material layers (7, 10) following on from one another along the curvature, the material layers (7, 10) being offset relative to one another so as to form the curvature.

9. The method according to claim 1, wherein at least one wall segment (2, 17, 18) is constructed that is made of a single material.

10. The method according to claim 1, wherein at least two wall segments (2, 17, 18) are constructed which are made of the same material(s).

11. The method according to claim 1, wherein, once a wall segment (2, 17, 18) has been constructed, this wall segment is processed on the outer side (6).

12. A device for producing a hollow body (1) with a hollow space (4) and a hollow body wall (3) delimiting the hollow space (4), which hollow body wall has a hollow space side (5) facing the hollow space (4) and an outer side (6) facing away from the hollow space (4), said device having a constructing device (11), by means of which the hollow body wall (3) can be created in portions by constructing wall segments (2, 17, 18) that are adjacent to one another, comprising a processing device (16), by means of which a wall segment (2, 17, 18) constructed by means of the constructing device (11) can be processed on the hollow space side (5) before a further wall segment (17, 18) can be constructed adjacently to the constructed wall segment (2, 17, 18) by means of the constructing device (11).

13. The device according to claim 12, wherein the constructing device (11) comprises a feed device (12) and a heating device (14), it being possible to feed material for a wall segment (2, 17, 18) in the solid state by means of the feed device (12), and to plasticise, by means of the heating device (14), the solid material for the wall segment (2, 17, 18) fed by means of the feed device (12) , and to construct the wall segment (2, 17, 18) from the material plasticised by means of the heating device (14).

Description

[0032] The invention will be explained in greater detail on the basis of exemplary schematic illustrations, in which:

[0033] FIGS. 1 to 9 show the production of a hollow body in the form of a sphere by means of a device provided for this purpose.

[0034] According to FIGS. 1 and 2, a first wall segment 2 of a sphere shell 3 provided as a hollow body wall is constructed in a first phase of the production of a hollow body formed as a sphere 1 and shown in FIG. 8 and in the sectional illustration of FIG. 9 immediately before completion. The sphere shell 3 delimits a hollow space 4 of the sphere 1 and has a hollow space side 5 facing the hollow space 4 and an outer side 6 facing away from the hollow space 4 (FIG. 9).

[0035] In order to construct the wall segment 2, a disc-like lower material layer 7 of the material of the sphere shell 3 is applied to a pin-like spacer 8. By means of the spacer 8, the lower material layer 7 of the wall segment 2 is held at a distance from a base plate 9. A plurality of sphere shells 3 can be arranged side by side on the base plate 9 in the illustrated manner.

[0036] A plurality of annular material layers 10 of material of the sphere shell 3 are applied in succession to the disc-like lower material layer 7 of the wall segment 2.

[0037] For this purpose, a constructing device 11 is used, which is illustrated inter alia in FIG. 4.

[0038] The constructing device 11 comprises, as feed device, a material feeder 12, which is attached to a robot arm (not shown) of the constructing device 11. By means of the material feeder 12, the material of the sphere shell 3 is fed as material wire 13 to the working point. The material feeder 12 corresponds in terms of its construction and operating principle to known devices for feeding welding wire in gas shielded metal arc welding.

[0039] At the working point, the material wire 13 fed by the material feeder 12 is plasticised by addition of heat by means of a laser head 14 serving as heating device and a laser beam 15 directed from the laser head 14 to the working point. The laser head 14 is also mounted on a robot arm (not shown) of the constructing device 11. In a numerically controlled manner, the robot arm with the material feeder 12 and the robot arm with the laser head 14 travel over the circular path along which the annular material layers 10 of the wall segment 2 are to be constructed from the plasticised material of the material wire 13.

[0040] In order to form the curvature of the sphere shell 3, the annular material layers 10 of the wall segment 2 are offset in the radial direction of the sphere shell 3 relative to the disc-like lower material layer 7 and also relative to one another. This results in a stepped course of the wall segment 2 of the sphere shell 3 both on the hollow space side 5 and on the outer side 6, as can be seen from FIGS. 1 and 2.

[0041] Once the plasticised material has cured, the wall segment 2 constructed from the lower material layer 7 and the further material layers 10 is processed firstly on its outer side.

[0042] A milling tool 16 of conventional design, which is attached to a robot arm (not shown) and which is guided along the outer side of the wall segment 2 with a numerically controlled movement and in so doing produces a smooth spherical shape from the step shape on the outer side of the wall segment 2, is schematically illustrated as processing tool in FIG. 3. Accordingly, the wall segment 2 is processed on the hollow space side 5 as per FIG. 3. The sphere shell segment formed by the wall segment 2 after the processing on the hollow space side 5 and on the outer side 6 can be seen in the lower part of FIG. 4.

[0043] Both on the hollow space side 5 and on the outer side 6, the material layer 10 applied last when constructing the wall segment 2 is omitted when processing the wall segment 2. On the last material layer 10 of the wall segment 2, after processing thereof, a further wall segment 17 of the sphere shell 3 is constructed adjacently to the previously constructed wall segment 2. Here, further material layers 10 of material of the sphere shell 3 are applied in the manner described above and illustrated in FIGS. 4 to 6. The wall segment 17 is also processed by means of the milling tool 16 on the outer side and on the hollow space side 5 after the solidification of the material that has been plasticised for being worked (FIG. 7). When processing the wall segment 17, the material layer 10 last applied is also omitted.

[0044] A further wall segment 18 is constructed on the last material layer 10 of the wall segment 17, adjacently to the previously constructed wall segment 17. Following the construction of the wall segment 18 and the subsequent curing of the material used to construct the wall segment 18, the wall segment 18 is also processed in the above-described manner by means of the milling tool 16 on the outer side 6 and on the hollow space side 5 (FIGS. 8 and 9). Also on the wall segment 18, the material layer 10 last applied is omitted from the processing.

[0045] The sphere shell 3 of the sphere 1 is then completed, apart from a shell opening 19. The shell opening 19 is required so as to be able to introduce the milling tool 16 for processing the hollow space side 5 of the wall segment 18 into the hollow space 4. Due to the spatially confined conditions, a milling tool 16 of small design is used in this case.

[0046] Once the processing of the wall segment 18 is complete, the milling tool 16 is removed from the hollow space 4 of the sphere shell 3 and the shell opening 19 is closed by means of the manufacturing device 11. Alternatively, in order to close the shell opening 19, it is possible to apply a disc-like upper material layer of material of the sphere shell 3 corresponding to the disc-like lower material layer 7 of the wall segment 2 to the material layer 10 created last when constructing the wall segment 18.

[0047] The closure of the shell opening 19 is provided on the outer side 6 with the desired smooth sphere surface by means of the milling tool 16. Lastly, the sphere shell 3 is separated from the spacer 8 and, if necessary, is processed at the point of attachment of the spacer 8 in order to produce a smooth sphere surface.