DE102004058013B3 - Aircraft wing structure manufacturing method, involves forming elevating projections at surface of substrate layer, and forming one projection into integral profile-like reinforcing unit e.g. stringer, by deformation using one cylinder - Google Patents

Abstract

The method involves mechanically or chemically structuring substrate layers (100) by partially removing a material from the substrate layers, and forming elevated projections at surface of the substrate layers. One of the elevated projections is formed into an integral profile-like reinforcing unit e.g. T-shaped stringer (300), by deformation using one of the cylinders, on the substrate layers. An independent claim is also included for an application of a method for manufacturing a wing structure for an aircraft.

Description

The The invention relates to a method for producing a structural structure with a stiffening element for an airplane.

To the Increase stability the outer skin of a Plane and to suppress the propagation of a crack in the outer skin due to a strong Mechanical load or material fatigue aircraft structures are often with equipped so-called stringers. A stringer is a metal track that sticks to the inside of a skin sheet (the aircraft outer skin) independently is incorporated by the actual planking. Such stringers can the propagation of a resulting crack in the outer skin inhibit and thus avoid a failure of the structure.

Become a fuselage formed of interconnected skin sheets, on which stiffening elements are attached. There are different methods of joining of skin sheets with stiffening elements known. For this will be according to the state the technology used riveting, gluing and welding. In other words Skin plate and stiffening elements initially as separate components made and subsequently connected consuming each other.

Out DE 196 39 667 C1 and DE 198 44 035 C1 is a structural component in welded skin stringer construction known. Profiles - designed as stringers or frames - are welded onto large-size skin sheets by means of laser beam welding.

For many Applications are integrally provided skin sheet stringer structures advantageous. Conventional are lightweight metallic structures like wing fields or hull fields over a complex process with ironing the outer shell and riveting the stringer. For the production of the shell, the production of stringers as well as the assembly are a variety required by method steps.

DE 100 07 995 C2 discloses a structural component, in particular for an aircraft, which consists of at least one skin panel and stiffening elements, the stiffening elements are formed in the longitudinal direction as stringer and in the transverse direction as stiffening and form a unitary component with the skin panel, wherein the structural component made of a semi-finished and as Milled part is formed, the skin panel reinforcements and / or erosion and the stiffening elements form bridge supports, which have different web heights depending on load.

DE 199 60 909 A1 discloses a large-scale structural component for an aircraft, which consists of at least one skin panel, wherein the skin panel is formed from at least one extrusion panel, wherein the extrusion panel substantially comprises a base member and a plurality of integral, longitudinal stiffening elements.

It It is an object of the invention to provide a method for producing a To create profile, in which the manufacturing cost justifiable is low and the profiles produced good mechanical properties exhibit.

This Problem is solved by a method for producing a supporting structure with at least one integral profile-like stiffening element for an aircraft and by the use of such a method of manufacture an integral profile-like stiffening element as a structural structure solved in an aircraft with the features according to the independent claims.

at the method according to the invention For producing a profile, a substrate layer is structured in such a way that that at least one laterally (i.e., laterally) limited structure on the surface the substrate layer is formed. Furthermore, the at least one laterally limited structure by means of at least one forming roller deformed, which is formed on the substrate layer a profile.

Furthermore is the use according to the invention a method with the above-described features for manufacturing a profile created as a structural structure in an aircraft.

One Aspect of the invention is to be seen in that on a substrate layer, especially in the form of a thin-film support, initially off the surface protruding projections by means of a suitable structuring technique are worked out. These protruding structures are then by means of a forming roll (and possibly additional Elements), so that by means of reshaping a supernatant Profile can be formed with a predetermined geometry.

Thus, using a forming roll (for example, a nip roll), a protruding structure is reformed (for example, cleaved to obtain a T-structure) on a sheet substrate, and by integrating the material of the substrate layer, an integral structure of the remaining sheet material and one therewith integrally connected profile of any shape and Design formed.

To the Forming according to the invention of a supernatant a thin-film support can be so-called Nip rolls or flow gaps used (as described, for example, in Groche, P., Vucic, D., Fritsche, D., Jöckel, M. "Stiffness Optimized Lightweight construction through new forming processes for sheet metal ", in: Siegert, K." Recent developments in sheet metal forming ", Frankfurt, MAT INFO Materials Information Society 05/2004, pages 201 bis 222 are disclosed).

Consequently allows It is the invention, any profiles - especially for manufacturing of structural structures, more particularly in an aircraft - to manufacture, in particular, integral stringer structures or frame structures can be formed. Such stringers or frames can be used for example in a hull field or in a wing field, or in floor supports inside of an airplane. Thus, the invention particularly discloses a Method for producing lightweight metallic structures, such as Hull shells or wing shells, with integrated stringers.

According to the invention is a Forming process in an advantageous manner, in particular on the production applied by hull fields. At so-called nip rolls or flowing columns can Sheets in a forming process by appropriate rollers or rollers split and deformed.

The Invention describes (for example for the production of lightweight structures of hull fields with integrated stringers) a method, which according to a embodiment works with six process steps: contour milling of an edge of a workpiece to be machined substrate; mill the inside of the substrate (for example, a sheet), here below otherwise leaving material for later forming to form of stringers; Nip rolls of the stringer; Placement in a mold; creep forming; Carry out a surface protection method, preferably at 250 ° C.

Further is it according to the invention allows the forming processes the Spaltwalzens the stringer and Kriechformens in a common single forming step to combine. This can be the bend of the substrate (for example a hull field) over the rolls already during the Forming the laterally limited structures (i.e., the supernatants) by means of the nip rolls are generated. With this variant of the invention are saved two more process steps. This allows manufacturing a profile with additional reduced effort, for example, using only four steps: contouring the edge of the substrate; mill the inside of the sheet metal (including, inter alia, leaving the material for later forming the stringer); Splitting rollers of the stringer with bending of the hull field; Surface protection, for Example by treatment at 250 ° C.

By the application of the invention a Umformwalzverfahrens (such as the gap rolling) for Manufacture of integral stiffening elements (such as Stringer or Spanten) in an airplane, the manufacturing process, in particular for hull fields or wing fields, dramatically simplified and thus cheapened. From a great variety of steps according to the state The technique required is a reduction to six, four and even fewer process steps possible. A reduction in the Number of process steps goes with a reduction of the manufacturing effort in terms of time and costs.

The inventive method the gap rolling of integral stringers has a great potential, metallic lightweight structures, for example of hulls and wings cost-effective and more powerful to be able to produce.

Thus, according to the invention made of a simple sheet metal (for example made of aluminum or steel) by rolling over projecting from this sheet supernatants profiles are formed, the number of such profiles or their size to each other be tuned and optimized. For example, a Variety of such profiles are used as stringers or frames, which are made relatively small. Or the number of such profiles can be reduced as its dimension is increased.

preferred Embodiments of the invention will become apparent from the dependent claims.

in the Further, embodiments of the method for producing a Structure with at least one integral profile-like stiffening element for a Aircraft described. These embodiments also apply to the use according to the invention.

The Substrate layer can be removed by mechanical or chemical abrasion be structured. As a mechanical removal method, for example a milling process be used opposite a chemical removal process (for example, an etching process in combination with an upstream masking method) better environmental compatibility shows.

The at least one raised supernatant or the at least one laterally limited (and ver tikal from the substrate protruding) structure can be reshaped by a first lateral boundary is pressed against a first roller and simultaneously pressed against a second lateral boundary, a second roller. By means of simultaneous and preferably symmetrical pressing of two forming rollers (for example two nip rollers) on end sections of the laterally delimited structures, a corresponding forming force can be exerted on both sides on the laterally delimited structure, which allows the material to be formed to form the profile.

alternative the at least one raised supernatant or at least a laterally limited structure are reshaped by attaching to a first lateral delimitation of the roller and simultaneously pressed on a second lateral boundary a back pressure is applied. For example, can in area From a non-moving element, a back pressure on one side the laterally limited structure are exerted, whereas on the other side Edge region of the laterally limited structure a rotating forming roller pressed which deforms the material of the laterally limited structure so that thereby a profile is formed.

To the pressing the at least one roller may have a horizontal and / or a vertical surface of the at least one integral profile-like stiffening element or Profils by pressing be smoothed by at least one pressure roller. For example can be a T-shaped Profile to be generated by first a nip roll as forming roll a laterally limited structure transforms to forming the profile. The profile produced in this way can then smoothed or finely adjusted by, for example, two rollers on the web of the T-shaped profile with rotating surfaces be pressed and simultaneously pressure on the upper limit of the T-shaped profile by means of an additional roller exercised becomes.

In front For structuring, the substrate layer may be a milling method for contouring an edge of the substrate layer. In other words The substrate layer can be cut to a suitable dimension or milled. In particular, you can the long edges a sheet for this milled become.

To the forming by means of the at least one roller, the substrate layer be bent. This allows a stiffened panel a desired desired geometry (cylindrical or spherical) be generated so that the substrates so structured any Surface curvature or may have three-dimensional topography. The geometry of the substrate For example, an integral profile can be used as an outer skin be adapted to a plane.

alternative can already during forming (the laterally limited structure for forming the profile) be bent by means of the at least one roller, the substrate layer. In other words may be bending the substrate and reshaping the laterally limited ones Structure are combined into a common process step, something extra Cost advantages effected.

The Substrate layer may be formed using a creep molding process be bent. However, to bend the thin film support can also other bending methods are used.

The Substrate layer may be subjected to a surface protection process be to the surface process the processed substrate layer for a desired application. For example, forming a surface protection by means of tempering at for example 250 ° C be advantageous to a processed substrate layer as aircraft skin to be used.

When Substrate layer can be used a light metal sheet, for Example an aluminum sheet or a steel sheet.

Further the at least one raised supernatant or at least a laterally limited structure are reshaped such that the at least one integral profile-like stiffening element integral is produced with an aircraft skin element as a substrate layer. This stiffening element can, for example, as a stringer element or formed as a frame element. The aircraft skin element For example, as a hull shell element or as a wing shell element be formed. In this way, the invention provides a cost-effective Method for producing high-quality integral structures as Hull shell elements or as wing shell elements with integrated stiffening elements.

As a roll can advantageously be used a nip roll, as in other context in Groche, P., Vucic, D., Fritsche, D., Jöckel, M. "Stiffness-optimized lightweight by new forming processes for sheet metal", in: Siegert, K. "Recent developments in sheet metal forming", Frankfurt, MAT INFO Material Information Society 05/2004, pages 201 to 222 is used. Such a nip roll, in particular in an obtuse-angled geometry, can optionally be used in combination with two laterally provided auxiliary rolls in order to narrow a laterally delimited structure protruding from the substrate in the lateral direction and to increase it in the vertical direction, the influence the nip roll can be used to form a substantially T-shaped structure in a substrate distal end portion of the formed profile. Such a T-structure can advantageously serve as a stringer element.

embodiments The invention is illustrated in the figures and will be discussed below explained in more detail.

It demonstrate:

1 to 4 schematic views of a method for producing a structural component according to a first embodiment of the invention,

5 a schematic view of a method for producing a structural component according to a second embodiment of the invention.

Same or similar Components in different figures are given the same reference numerals Mistake.

The Representations in the figures are schematic and not to scale.

In 1 are aluminum sheets 100 . 101 shown, which are prepared by milling the longitudinal edges as substrate layers for a method for producing a structural component.

By means of a milling process, ie a mechanical removal process, the aluminum sheet 100 locally thinned and thus structured. This will, as in 2 shown a first laterally limited structure 200 and a second laterally limited structure 201 as supernatants of the aluminum sheet 100 formed, the material of the laterally limited structures 200 . 201 subsequently used to form profiles.

As in 3 will be shown below each of the laterally limited structures 200 . 201 deformed using nip rolls, thereby forming on the substrate layer 100 Stringer 300 are formed as profiles of a structural component.

For this, as in 3 shown, first at a right lateral boundary of the first laterally delimited layer sequence 200 a nip roll 301 pressed. Simultan is at a left lateral boundary of the first laterally limited layer sequence 200 by means of a pressure element 302 a counter-pressure exerted. This leads to a deformation of the laterally limited structure 200 , whereby a substantially T-shaped stringer 300 is formed.

After forming such a stringer 300 its surface is smoothed by, as in the right part of 3 shown at a left end portion of the longitudinal web of the stringer 300 a first pressure roller 303 is pressed flat, to a right end portion of the longitudinal web of the stringer 300 a second pressure roller 304 is pressed, and to a crosspiece of the stringer 300 a third pressure roller 305 is pressed.

In the 3 jointly shown components, namely the nip roll 301 and the pressure element 302 on the one hand and the first to third pressure rollers 303 to 305 on the other hand act on each of the stringers in succession 300 one.

In 4 is shown that starting from the in 3 structure shown the aluminum sheet 101 has been subjected to a creep molding process, so that the stiffened panel 3 placed in a predetermined desired geometry (cylindrical and spherical).

Subsequently, the layer sequence thus obtained may be subjected to a surface protection process at 250 ° C (not shown), so that the obtained structural component may be used as a fuselage member of an aircraft, the bent aluminum sheet 101 an airplane skin panel and the stringers 300 Can form stiffening elements.

In 5 is an alternative geometry for forming a laterally limited structure 200 (as in 2 shown) for forming a stringer 300 shown. For this purpose, an obtuse-angled gap roller 501 for reshaping the laterally limited structure 200 used, with a first auxiliary roll 502 and a second auxiliary roll 503 left side and right side of the cleavage to form the T-shaped profile 300 are provided as mechanical support. Clearly illustrated by the rolling around the laterally limited structure 200 Rolled up material in the vertical direction and thus shifted the center of gravity of the structural component upwards.

The Restricted invention in their execution not to the preferred embodiments shown in the figures. Rather, a variety of variants is conceivable, which of the illustrated solution and the principle of the invention also at basically different types of embodiments Use.

In addition, it should be noted that "having" does not exclude other elements or steps, and "a" or "an" does not exclude a plurality closes. It should also be appreciated that features or steps described with reference to any of the above embodiments may also be used in combination with other features or steps of other embodiments described above. Reference signs in the claims are not to be considered as limitations.

100

aluminum sheet

101

aluminum sheet

200

first laterally limited structure

201

second laterally limited structure

300

Stringer

301

nip roll

302

pressure element

303

first platen

304

second platen

305

third platen

501

obtuse nip roll

502

first auxiliary roll

503

second auxiliary roll

Claims (17)

Method for producing a supporting structure with at least one integral profile-like stiffening element ( 300 ) for an aircraft by working out the at least one integral profile-like stiffening element ( 300 ) from a substrate layer ( 100 . 101 ), wherein in the method the substrate layer ( 100 . 101 ) is structured by partially removing material in such a way that on the surface of the substrate layer ( 100 . 101 ) at least one raised supernatant ( 200 . 201 ) is formed; then the at least one raised supernatant ( 200 . 201 ) by forming by means of at least one roller ( 301 to 305 ) to the at least one integral profile-like stiffening element ( 300 ) on the substrate layer ( 100 . 101 ) is formed. Method according to claim 1, in which the substrate layer ( 100 . 101 ) is structured by means of mechanical or chemical removal. The method of claim 1 or 2, wherein the at least one raised supernatant ( 200 . 201 ) is formed by, at a first lateral boundary, a first roller ( 301 ) is pressed and simultaneously at a second lateral boundary, a second roller ( 301 ) is pressed. The method of claim 1 or 2, wherein the at least one raised supernatant ( 200 . 201 ) is formed by at a first lateral boundary of the roller ( 301 ) is pressed and simultaneously at a second lateral boundary a back pressure ( 302 ) is exercised. Method according to claim 3 or 4, in which, after the pressing of the at least one roll ( 301 ) a horizontal and / or a vertical surface of the at least one integrally profile-like stiffening element ( 300 ) by pressing at least one pressure roller ( 303 to 305 ) is smoothed. Method according to one of claims 1 to 5, wherein the substrate layer ( 100 . 101 ) before structuring a milling method for contouring an edge of the substrate layer ( 100 . 101 ). Method according to one of claims 1 to 6, wherein after the forming by means of the at least one roller ( 301 ) the substrate layer ( 100 ) is bent. Method according to one of claims 1 to 6, wherein during the forming by means of the at least one roller ( 301 ) the substrate layer ( 100 . 101 ) is bent. Method according to Claim 7 or 8, in which the substrate layer ( 100 . 101 ) is bent using a creep molding process. Method according to one of claims 1 to 9, wherein the substrate layer ( 100 . 101 ) is subjected to a surface protection process. Method according to one of claims 1 to 10, in which as a substrate layer ( 100 . 101 ) A light metal sheet is used. Process according to one of Claims 1 to 11, in which the substrate layer ( 100 . 101 ) An aluminum sheet is used. Method according to one of claims 1 to 12, wherein the at least one raised supernatant ( 200 . 201 ) is formed such that the at least one integral profile-like stiffening element ( 300 ) integral with an aircraft skin member as a substrate layer ( 100 . 101 ) is formed. The method of claim 13, wherein as said at least one integral profile-like stiffening element ( 300 ) a stringer element and / or a bulkhead element is formed. A method according to claim 13 or 14, wherein the Aircraft skin element as a hull shell element or as a wing shell element is formed. Method according to one of claims 1 to 15, in which as a roller a nip roll ( 501 ) is used. Use of a method according to one of claims 1 to 16 for producing at least one integral profile-like stiffening element ( 300 ) as a structural structure in an aircraft.