METHOD FOR PRODUCING A FUSELAGE PORTION

Abstract

A method for producing a fuselage portion, in particular for an aircraft or spacecraft, has the following method steps: welding a skin portion containing a thermoplastic material with a former containing a thermoplastic material in the region of a predetermined welding zone; and connecting an attachment element, configured as a crack stopper, to the skin portion and to the former in the region of the welding zone.

Claims

1. A method for producing a fuselage portion, comprising the steps: welding a skin portion containing a thermoplastic material with a former containing a thermoplastic material in a region of a predetermined welding zone; and connecting an attachment element, configured as a crack stopper, to the skin portion and to the former in the region of the welding zone.

2. The method of claim 1, wherein the former is configured with a through-recess at which the welding zone is interrupted, the attachment element being arranged in the region of a runout or beginning, adjoining the through-recess, of the welding zone.

3. The method of claim 1, wherein the attachment element is connected to at least one of the skin portion and the former in at least one of a form-locking and force-locking manner.

4. The method of claim 3, wherein the attachment element is connected by rivets or screws.

5. The method of claim 1, wherein the attachment element is bonded integrally with at least one of the skin portion and the former.

6. The method of claim 5, wherein to produce an integral bond with the skin portion and with the former, the attachment element is also melted into the welding zone during the welding process.

7. The method of claim 6, wherein at least one of the skin portion and the former are provided as fiber composite components, the attachment element displacing fibers of the fiber composite component during welding in the welding zone without destroying them.

8. A fuselage portion comprising: a skin portion; and a former, wherein the skin portion and the former each contain a thermoplastic material and are welded together in a welding zone, and wherein provided in the region of the welding zone is an attachment element which is connected to the skin portion and to the former and is configured as a crack stopper.

9. The fuselage portion according to claim 8, wherein a stringer is provided which runs transversely to the former and is connected to the skin portion, the former having in an intersection region a through-recess for the stringer, at which through-recess the welding zone is interrupted.

10. The fuselage portion according to claim 9, wherein the attachment element is arranged in the region of a runout or beginning, adjoining the through-recess, of the welding zone.

11. The fuselage of claim 8, wherein the attachment element is configured such that it is connected to at least one of the skin portion and the former in at least one of a form-locking and force-locking manner.

12. The fuselage of claim 11, wherein the attachment element is a rivet or a screw.

13. The fuselage portion of claim 8, wherein the attachment element is configured such that it is integrally bonded with at least one of the skin portion and the former.

14. The fuselage portion of claim 13, wherein the attachment element is a pin which is melted into the welding zone.

15. The fuselage portion according to claim 13, wherein at least one of the skin portion and the former is configured as a fiber composite component, fibers of the fiber composite component being arranged such that they are displaced, without being destroyed by the attachment element in the welding zone.

16. The fuselage portion of claim 8, wherein a multiplicity of attachment elements is provided, the attachment elements being respectively arranged in the welding zone at a predetermined distance from one another.

17. The fuselage portion of claim 16, wherein the attachment elements are arranged in the welding zone at a distance of more than 10 cm.

18. The fuselage portion of claim 17, wherein the attachment elements are arranged in the welding zone at a distance of more than 50 cm.

19. The fuselage portion of claim 18, wherein the attachment elements are arranged in the welding zone at a distance between 50 cm and 1 m.

20. An aircraft or spacecraft, having a fuselage which has a fuselage portion comprising a skin portion; and a former, wherein the skin portion and the former each contain a thermoplastic material and are welded together in a welding zone, and wherein provided in the region of the welding zone is an attachment element which is connected to the skin portion and to the former and is configured as a crack stopper.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In the following, the invention will be described in more detail on the basis of an embodiment with reference to the accompanying drawings. In the drawings, the same reference numerals denote identical or functionally identical components, unless indicated otherwise.

[0036] FIG. 1 is a schematic cross-sectional view of a fuselage portion.

[0037] FIG. 2 is a perspective view of an aircraft or spacecraft.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] The fuselage portion 1 shown in FIG. 1 has a skin portion 2 and a former 3.

[0039] The skin portion 2 has a curved shape corresponding to the round form of a fuselage 12 shown in FIG. 2. Accordingly, the former 3 also has a corresponding curvature on its radial outer side to which the skin portion 2 is attached.

[0040] The fuselage portion 1 also has a plurality of stringers 8 which are oriented substantially in the longitudinal direction of the fuselage 12 which, in the cross-sectional view shown, runs into the plane of the drawing.

[0041] The stringers 8 intersect the former 3 in intersection regions 9, for which purpose through-recesses 6 are respectively provided in the former 3. Here, the through-recesses 6 are curved purely by way of example.

[0042] The skin portion 2 and the former 3 are formed, for example, from a fiber composite material with a thermoplastic matrix. In particular, the skin portion 2 can be produced by a tape laying method.

[0043] The attachment of the skin portion 2 to the former 3 is realized by welding zones 4 in which the skin portion 2 is welded thermoplastically to the former 3.

[0044] The welding zones are interrupted in the region of the through-recesses 6.

[0045] Provided inside each of the welding zones 4 are additional attachment elements 5 which are configured as crack stoppers. They are respectively arranged in the region of a beginning or runout 7 of a welding zone 4.

[0046] A beginning or runout respectively denotes the end of a continuous welding zone. For example, it can be the beginning or a runout of a weld seam.

[0047] The welding zone 4 can have a width which exceeds the width or the diameter of the attachment element 5.

[0048] To produce the fuselage portion 1, the skin portion 2 and the former 3 are welded thermoplastically in the predetermined welding zones 4. For example, this can be carried out by means of heat conduction welding or ultrasonic welding or hot-gas welding. Other welding processes, for example a laser beam welding process, are also possible.

[0049] For example, in hot-gas welding, the surfaces to be joined together are heated by hot air to the welding temperature and are welded under pressure. In particular, the welding process comprises the following steps: preparing the welding surfaces in the region of the predetermined welding zone; heating the welding zone; joining together the skin portion and the stringer while simultaneously applying a welding pressure; cooling the welded joint while maintaining the welding pressure; removing the welding pressure from the welded material.

[0050] Furthermore, in the welding zones 4, the attachment elements 5 are introduced in the region of a beginning or runout 7 of each welding zone 4.

[0051] For example, during production, the attachment elements 5 can be introduced into the welding zone 4 after welding. In this case, the attachment elements 4 can be rivets which are introduced into the solidified welding zone 4. Alternatively, they can also be all kinds of conventional types of bolts.

[0052] As a further alternative, the attachment element 5 can also be melted into the welding zone 4 during the welding process. For example, in this case, the attachment elements 5 can be pins which are melted into the welding zone during welding. For this purpose, the pins can be positioned inside the predetermined welding zone 4 before welding, for example. In particular, appropriate positioning recesses, for example holes, can be provided in the predetermined welding zone before welding. When the thermoplastic material is melted on, the attachment elements are also melted or embedded therein and in this way, are bonded integrally with the thermoplastic material.

[0053] The fibers of the fiber composite material of the skin portion and of the former are not damaged thereby. Instead, the fibers can be displaced by the attachment elements in the melting bath, so that advantageously the fibers are not damaged.

[0054] In this respect, the attachment elements themselves can remain fixed, so that after the thermoplastic melt has solidified, they are embedded in their original form in the intended position and are integrally bonded with the skin portion 2 and with the former 3.

[0055] The welded joint between the former and the skin portion is realized in a damage-tolerant manner by means of the attachment elements 5. In the event of a detachment, a possible crack or crack progression is always halted at the closest attachment element 5. In this way, the fuselage portion 1 can be certified for aviation in spite of a welded joint between the skin portion and the former.

[0056] The stringers 8 are configured, for example, as omega stringers and are also formed from a fiber composite material with a thermoplastic matrix. Accordingly, the stringers can also be provided such that they are welded with the skin portion.

[0057] FIG. 2 shows an aircraft or spacecraft 11 in the form of a passenger aircraft.

[0058] The aircraft or spacecraft 11 has a fuselage 12 which has at least one fuselage portion 1 formed according to FIG. 1.

[0059] The entire fuselage 12 can be produced in the construction style described according to FIG. 1 and thus contains a plurality of fuselage portions 1 of this type.

[0060] Although the present invention has been described above on the basis of various embodiments, it is not restricted thereto but can be modified in many different ways.

[0061] For example, additional attachment elements 5 can be also be arranged between the beginning and the runout 7 inside a welding zone 4. This is particularly appropriate when the stringers 8 or the through-recesses 6 are spaced apart from one another by more than 1 m to halt possible cracks at an early stage. The additional attachment elements 5 can then also be arranged at a distance of between 50 cm and 1 m from the attachment elements provided at the beginning or runout 7.

[0062] Instead of omega stringers, it is also possible to provide other types or shapes of stringers 8. Accordingly, the through-recesses 6 of the former 3 do not necessarily have to be curved, but they can also have a different shape which is adapted to the shape of the stringers.

[0063] Furthermore, to realize the concept according to the invention, the stringers do not necessarily also have to contain a thermoplastic material or have to be welded onto the skin.

[0064] The thermoplastic material is only necessary for the former 3 and the skin portion 2 to form the welding zone. However, it would also be possible to use a thermoplastic material locally only or just as a layer, an outer coating or optionally as an additional material for joining the former to the skin portion, so that the former and/or the skin portion optionally only contain the thermoplastic material in the welded state in the region of the welding zone.

[0065] While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.