FASTENING SYSTEM WITH TOLERANCE COMPENSATION FOR THE INTERIOR OF AN AIRCRAFT

Description

Technical area

[0001] The present description relates to a fastening system for fastening a component to a fuselage structure in an interior of an aircraft, as well as to an aircraft with such a fastening system and at least one component. Technical background

[0002] The fuselage of a commercial aircraft typically contains a passenger cabin with a multitude of furnishings. To arrange the furnishings, a variety of brackets are mounted on the inside of the fuselage structure. These brackets are individually tailored to the furnishings and allow for their secure mounting. For larger commercial aircraft with fuselage lengths well over 10 m, manufacturing tolerances are to be expected, which must be taken into account when connecting the brackets. To achieve a clearly defined geometry, the individual brackets must be adjusted to compensate for dimensional deviations in the fuselage structure.

[0003] DE 10 2020 108 392 A1 discloses a fastening device for fastening a cabin interior component to a connecting structure of an aircraft cabin. The connecting structure comprises a fastening tube, an arrangement of an inner sleeve and an outer sleeve, and a retaining element for aligning the cabin interior component to the fastening tube.

[0004] DE 10 2020 128 089 A1 proposes a positioning bushing used to adjust a distance and orientation between two aircraft components. The positioning bushing comprises an outer bushing that is inserted into a first aircraft component and an inner bushing that is inserted into the outer bushing. The inner bushing is generally suitable for receiving an aircraft component, but can also only receive conventional fasteners. Overall, the positioning bushing enables the first aircraft component to be fastened to the second aircraft component. The outer bushing and the inner bushing are designed such that, when the inner bushing is inserted into the outer bushing, rotation of the inner bushing relative to the outer bushing is blocked. The positioning bushing is used in aircraft fastening arrangements.In particular, the positioning bushing is used for connecting parts of the aircraft structure, such as the primary structure or the secondary structure. Description

[0005] The task can be considered to propose an alternative fastening system that realizes a simple tolerance compensation and aligns and holds a fastening tube parallel to a longitudinal axis of the aircraft.

[0006] This object is achieved by a fastening system having the features of independent claim 1. Further embodiments emerge from the dependent claims and from the following description.

[0007] A fastening system for fastening a component to a fuselage structure in the interior of an aircraft is proposed, comprising a plurality of rigid holding elements for fastening to the fuselage structure, a position compensation device on each of the holding elements, at least one elongated base body connectable to the holding elements, and at least one fastening element connectable to the base body and a component to be fastened, wherein the holding elements each have at least one structure holder for connection to the fuselage structure and a receiving holder for receiving the respective position compensation device, wherein the position compensation device has a first position compensation bushing and a second position compensation bushing, wherein the first position compensation bushing is rotatably arranged in the receiving holder and has an eccentric first bore,wherein the second position compensation bushing is rotatably arranged in the first position compensation bushing and has an eccentric second bore, wherein the base body extends through the second opening and is held therein, and wherein the base body has first connecting means along at least half of its length, which are complementary to second connecting means of the at least one fastening element, so that the at least one fastening element can be connected to the base body at different positions.

[0008] The retaining elements are intended to be attached to the primary structure. They preferably comprise a plurality of structural holders to achieve fixation to the primary structure. Such a structural holder can, for example, be an opening, a bushing, a flange, or the like, which can be connected to the primary structure by means of a bolt or other fastening element. A retaining element could, for example, be intended to be attached to a fuselage frame.

[0009] The fastening system according to the invention comprises a plurality of such holding elements, which are preferably fixed at a distance from one another along the longitudinal direction of the cabin in order to arrange the elongated base body thereon. Provision could be made to arrange such a holding element on each of the fuselage frames along a substantial part of the longitudinal direction of the aircraft. If both longitudinal halves of the aircraft's interior are to be equipped with components, it is advisable to arrange base bodies on both sides within the aircraft's interior.

[0010] The support brackets of all support elements on a respective side of the fuselage structure are arranged such that an externally generated reference line, parallel to the aircraft's longitudinal axis, passes through all support brackets. A reference line could, for example, be generated by a laser and guided through the support brackets. The goal is to adjust the position compensation devices of all support brackets in a row such that the reference line coincides with the center axis of the elongated base body.

[0011] The holder of a holding element could have an opening, a bore, or a bushing into which the first position compensation bushing can be inserted. This bushing can then rotate in the holder. The second position compensation bushing is rotatably arranged in the first position compensation bushing. Since the first opening and the second opening are each arranged eccentrically, by rotating both position compensation bushings by certain angles, the second opening can be positioned so that its center axis coincides with the reference line. If this is done for each position compensation device in a series of holding elements, the entirety of all second openings is precisely aligned with the reference line, and the center axis of the base body that can be positioned therein coincides with the reference line.

[0012] It is understood that the first position compensation bushing and the second position compensation bushing are fixable. Various options are available for this. For example, both position compensation bushings could each have a circumferential collar in which openings, a profile, or grooves are arranged that are suitable for accommodating locking pins, engagement teeth, or other fixing elements.

[0013] The precise positioning of the elongated base body provides a base for components to be installed in the fuselage structure, which is decoupled from the fuselage structure in terms of its position and orientation. Despite typical manufacturing tolerances, precise alignment of the base body is achieved, eliminating the need for additional tolerance compensation on the components to be attached.

[0014] The alignment of the position compensation devices does not have to be done manually, but could also be automated, for example by means of a robot. This could be placed on a cabin floor during aircraft assembly and move to each of the holding elements one after the other. There, the respective deviation of the center axis of the second opening from the projected reference line could be examined in order to determine the necessary rotations of the two position compensation bushings based on the determined deviation. The necessary rotations can then be implemented by the robot. This would not only reduce the personnel required inside the cabin during assembly, but also increase the precision of the adjustment. The arrangement of eccentric openings inside one another is a particularly simple and mechanically reliable solution for quickly compensating tolerances.

[0015] The base body can, in particular, be designed as a tube with a hollow space. Furthermore, the base body could be subdivided, so that several sections can be formed and secured consecutively in the longitudinal direction in the fuselage structure.

[0016] A combination of first connecting means and second connecting means is provided for connecting the base body to fastening elements. The two connecting means are designed to complement each other, so that the respective fastening element can be attached and fastened in different positions on the base body. It is conceivable that the first connecting means is provided along a substantial part of the length of the base body, so that a fastening element can be attached at virtually any desired location on the base body. The elongated base body thus represents a reliably positioned and completely flexible base for attaching fastening elements.

[0017] According to the invention, the first connecting means have at least one first toothing extending transversely to the longitudinal axis of the base body. The toothing is formed as a sequence of grooves and elevations. The grooves or elevations are transverse to the longitudinal axis of the base body. The fastening element could thus be brought onto the base body in a direction transverse to the longitudinal axis and there engaged with the first toothing. The fastening element could be pushed on, for example, in a radial direction parallel to the grooves. Direct fixation along the longitudinal axis is achieved if the fastening element has engagement means corresponding to the first toothing, for example a second toothing.

[0018] In an advantageous embodiment, the base body has the first toothing on two opposing radial edge sections. The radial edge sections could be arranged on a top and / or bottom side of the cross-section of the base body. The fastening element could grip the base body like a pair of pliers, thereby engaging the two toothed edge sections.

[0019] In an advantageous embodiment, the base body has a round cross-section. The cross-section could, in particular, be circular, allowing a variable longitudinal position of the base body in the second opening. The diameters of the base body and the second opening could form a sliding or loose fit. This makes it possible to push the base body through several consecutive second openings.

[0020] In an advantageous embodiment, the first toothing is formed in the round cross-section, allowing the base body to be displaced in the second opening. The toothing does not protrude outward from the round cross-section and thus does not prevent the round cross-section from being displaced in the longitudinal direction of the base body. The first toothing could be formed such that two diametrically opposed edge sections are interlocked parallel to each other. The height of the toothing could be less than half the radius of the base body.

[0021] In an advantageous embodiment, the fastening system further comprises a plurality of securing elements designed to secure the base body to the retaining elements in the axial direction. This enables the transmission of forces in the longitudinal direction, i.e., along the base body, into the fuselage structure. The securing elements could be assigned to each or most of the retaining elements, thus ensuring a very good distribution of axial forces into the fuselage structure.

[0022] In an advantageous embodiment, the securing elements are designed to be arranged in the axial direction in front of and behind the holding elements and to be connected to the base body. The securing elements could, for example, be brought into engagement with the first toothing and thus be fixed to the base body. If the two securing elements assigned to the respective holding element are engaged with the first toothing and abut flush against the position compensation device, this achieves axial fixation of the base body to the position compensation device.

[0023] In an advantageous embodiment, the at least one fastening element has a radial recess which is complementary to the base body and which can be plugged radially from the outside onto the base body, wherein the at least one recess has a second toothing which is complementary to the first toothing. The radial recess could be designed approximately like the letter U and comprise two leg surfaces which run essentially parallel to one another, between which a curved surface runs on one side. The second toothing can be arranged at least on the two leg surfaces and engages with the first toothing. The fastening element can thus, as already mentioned above, be plugged radially from the outside onto the base body in practically any position in order to achieve direct axial fixation.

[0024] In an advantageous embodiment, the base body has, on at least one of the radial edge sections, a first securing groove extending in the longitudinal direction, which corresponds to a second securing groove in the recess of the fastening element, wherein the fastening system further comprises a securing pin which is shaped complementarily to a securing opening formed by the first securing groove and the second securing groove aligned therewith, so that it fixes the fastening element and the base body. The first securing groove could extend along the entire length of the base body. The second securing groove is aligned with the first securing groove, so that a common cutout is generated. By inserting the securing pin in the axial direction, ieParallel to the base body, the fastening element and the base body are fixed relative to each other in such a way that the fastening element cannot be removed from the base body. The first locking groove and the second locking groove thus enclose the locking pin and cannot be displaced or twisted relative to each other due to the material embedded in both locking grooves. Both locking grooves could have a semicircular cross-section.

[0025] In an advantageous embodiment, the first position compensation bushing and the second position compensation bushing each have a circumferential collar on which circumferential toothing can be introduced for engaging a tool. This enables, in particular, automated adjustment of the rotational position of the position compensation bushings. The toothing could be designed like a gearwheel, so that a correspondingly toothed pinion can be engaged with it to enable adjustment of the position compensation bushings.

[0026] The invention further relates to an aircraft comprising a fuselage with a fuselage structure and at least one component which is fastened to the fuselage structure by means of a fastening system as described above.

[0027] In an advantageous embodiment, the component is a service unit for passengers or an overhead storage compartment.

[0028] In an advantageous embodiment, the fuselage has a longitudinal axis, a right side and a left side, wherein along a substantial part of the right side and the left side of the fuselage at least one base body is mounted on the fuselage structure parallel to the longitudinal axis.

[0029] In an advantageous embodiment, at least two base bodies are arranged on the right and left sides, spaced apart from one another and running parallel to the longitudinal axis. This allows a type of truss structure to be constructed that supports the components. A first bar could be attached to a first base body, and a second bar to a second base body. The ends of the bars facing away from the base bodies could form a node connected to a component. The component could be connected to several nodes arranged consecutively in the longitudinal direction. Diagonal struts could also be used to stiffen the truss structure. Short description of the characters

[0030] The following examples are described in more detail with reference to the accompanying drawings. The illustrations are schematic and not to scale. Like reference numerals refer to like or similar elements. They show: Fig. 1: A schematic representation of a fastening system in two views. Fig. 2: A schematic representation of a robot adjusting position compensation bushings in two views. Fig. 3: A schematic view of the fastening element on the base body. Fig. 4a + 4b: Schematic representations of the fastening element on the base body with locking pin. Fig. 5: A schematic representation of locking elements. Fig. 6 - 8: Different representations of holding elements. Fig. 9: An aircraft. Detailed description of implementation examples

[0031] In Fig. 1 1 shows a fastening system 2 for fastening a component to a fuselage structure 4 in the interior of an aircraft in a top view in the axial direction and a lateral sectional view. This system includes a rigid holding element 6 with two limbs arranged at an angle to one another, which is fastened to the fuselage structure 4. For this purpose, the holding element 6 has two structure holders 8, each of which has a through-bore 10. A bolt could be inserted through this through-bore and connected to the fuselage structure 4. The holding element 6 further has a receiving holder 12 in which a position compensation device 14 is arranged.

[0032] Due to its two-leg design, the holding element 6 is designed to absorb forces in essentially two spatial directions, in this case the z- and y-directions, i.e., along a vertical axis and an outward-directed, lateral axis within the aircraft. Other variants with different force directions are conceivable.

[0033] The receiving holder 12 has a receiving opening 16 in which a first position compensation bushing 18 is rotatably mounted. This has a first opening 20 in which a second position compensation bushing 22 is arranged. This, in turn, has a second opening 24 in which an elongated base body 26 is arranged. The first opening 20 and the second opening 24 are each eccentrically designed, so that by rotating the first position compensation bushing 18 and the second position compensation bushing 22, the position of the second opening 24 can be adjusted over a large dimensional range in the zy-plane. This allows a central axis 30 of the second bore 24 to be adjusted to a reference line 28, for example, indicated by a laser beam. Consequently, regardless of the dimensional tolerance of the fuselage structure 4 and the holding element 6, the elongated base body 26 can be positioned very precisely in order to fasten components thereto.

[0034] In this embodiment, both position compensation bushings 18 and 22 have a circumferential collar 32 and 34. These each include a circumferential toothing 36. By engaging the circumferential toothing 36 with a pinion or the like, the two position compensation bushings 18 and 22 can be rotated to precisely adjust the position of the second opening 24 in space.

[0035] In this example, the support bracket 12 is designed as a cylindrical bushing 12, which is connected to both structural brackets 8 via stiffening brackets 38. This achieves a particularly high flexural rigidity.

[0036] Fig. 2 shows a two-side view of a cabin floor 40 in an interior 42 of an aircraft, with a robot 44 standing on the cabin floor 40. Several holding elements 6 are connected to the fuselage structure 4 and the robot 44 is in Fig. 2 in the process of adjusting the position of the second opening 24. For this purpose, the robot 44 has, for example, a detection device 46 for detecting the aforementioned reference line 28. The current position of the second bore 24 is also detected in order to rotate the tolerance compensation bushings 18 and 22 by means of a pinion 48 based on a deviation between the center line 30 and the reference line 28.

[0037] The base body 26 can, as in Fig. 3 shown, have a hollow profile. On a top side and a bottom side of the cross-section there is a first toothing 50 which lies completely within a circular cross-section of the base body 26. The first toothing 50 is penetrated by a first, semicircular groove 52 along the longitudinal axis of the base body 26. A fastening element 54 has a recess 56 which corresponds to the cross-section of the base body 26 and which here has approximately the shape of the letter U. A second toothing 60 which is complementary to the first toothing 50 is arranged on two opposite leg surfaces 58. The fastening element 54 can therefore be pushed radially laterally onto the base body 26 so that the first toothing 50 and the second toothing 60 engage with one another. The fastening element 54 is thus secured in the axial direction, i.e. along the x-axis.

[0038] Additionally, a second, semicircular groove 62 is provided in the fastening element 54, which adjoins the first groove 52 after the fastening element 54 is attached to the second toothing 60. The grooves 52 and 62 thus together form a circular cross-section. A locking pin can be inserted axially into this groove to secure the position of the fastening element 54 on the base body 26. The fastening element 54 has an interface 64 that can be connected to the component to be installed.

[0039] In the Fig. 4a und 4b This is shown in further views. Here, the first toothing 50 can also be seen, which runs transversely to the longitudinal direction of the base body 26. Fig. 4b shows a locking pin 66 which is inserted into the grooves 52 and 62.

[0040] Fig. 5 shows a possible embodiment of securing elements 68, which are designed, for example, similarly to the previously shown fastening elements 54 and can engage with the base body 26. For this purpose, the securing elements 68 can be arranged in flush contact directly in front of and directly behind the position compensation device 14 and fixed axially, so that, conversely, the fastening element 26 is fixed to the holding element 6.

[0041] Fig. 6 shows a further embodiment of a two-leg holding element 70, which has a total of four structure holders 72 in order to fasten the holding element 70 to two areas of the fuselage structure 4.

[0042] Fig. 7 shows a single-leg holding element 74, which is intended only for absorbing forces essentially in a single spatial direction, here along the z-axis, i.e., the vertical axis in an aircraft. Only two structural holders 72 are provided, which are arranged in line with the receiving holder 12. Holding elements 74 arranged in other spatial directions are also conceivable, for example, parallel to a y-axis or a z-axis, or obliquely thereto.

[0043] Fig. 8 shows a slightly modified variant in the form of a holding element 76, in which the receiving holder 12 is arranged in a different position than in the illustration from Fig. 7 is significantly shortened in the axial direction.

[0044] Finally, Fig. 9an aircraft 78 with a fuselage 80 formed by the fuselage structure 4 and an outer shell. In the interior 42, as shown on the right side of the aircraft, there are two base bodies 26, which extend parallel to each other and to the longitudinal axis x. For the sake of simplicity, the base bodies 26 for the left half of the aircraft have been omitted. A component 82 is shown with dashed lines, which is connected to the base bodies 26. In addition to the fastening elements 54, articulated rods could also be used to form a truss structure whose spatial position is determined by the base bodies 26.

[0045] In addition, it should be noted that "comprising" or "having" does not exclude other elements or steps and "a" or "an" does not exclude a plurality of reference signs in the claims are not to be considered as limiting. List of reference symbols

[0046] 2 Fastening system 4 Fuselage structure 6 Holding element 8 Structure holder 10 Through hole 12 Receptacle holder 14 Position compensation device 16 Receptacle opening 18 First position compensation bushing 20 First opening / bore 22 Second position compensation bushing 24 Second opening / bore 26 Base body 28 Reference line 30 Center axis 32 Circumferential collar 34 Circumferential collar 36 Circumferential toothing 38 Stiffening angle 40 Cabin floor 42 Interior 44 Robot 46 Detection device 48 Pinion 50 First toothing / first connecting means 52 First groove 54 Fastening element 56 Recess 58 Leg surface 60 Second toothing / second connecting means 62 Second groove 64 Interface 66 Locking pin 68 Locking element 70 Holding element 72Structural holder 74Retaining element 76Retaining element 78Aircraft 80Fuselage 82Component

Claims

1. Fastening system (2) for fastening a component (82) to a fuselage structure (4) in an interior (42) of an aircraft (78), comprising: a plurality of rigid holding elements (6, 70, 74, 76) for fastening to the fuselage structure (4), a position compensation device (14) on each of the holding elements (6, 70, 74, 76), at least one elongate base body (26) which is connectable to the holding elements (6, 70, 74, 76), and at least one fastening element (54) which is connectable to the base body (26) and a component (82) to be fastened, wherein the holding elements (6, 70, 74, 76) each have at least one structure holder (8) for connection to the fuselage structure (4) and a receiving holder (12) for receiving the respective position compensation device (14), wherein the position compensation device (14) comprises a first position compensation bushing (18) and a second position compensation bushing (22), wherein the first position compensation bushing (18) is rotatably arranged in the receiving holder (12) and has an eccentric first bore (20), wherein the second position compensation bushing (22) is rotatable in the first position compensation bushing (18) and has an eccentric second bore (24), wherein the base body (26) extends through the second opening (24) and is held therein, wherein the base body (26) has first connecting means (50) along at least half of its length, which are formed complementary to second connecting means (60) of the at least one fastening element (54), so that the at least one fastening element (54) can be connected to the base body (26) at different positions, and wherein the first connecting means have at least one first toothing (50) extending transversely to the longitudinal axis of the base body (26).

2. Fastening system (2) according to claim 1, wherein the base body (26) comprises the first toothing (50) at two opposite radial edge sections.

3. Fastening system (2) according to one of the preceding claims, wherein the base body (26) has a round cross-section.

4. Fastening system (2) according to claim 2 and 3, wherein the first toothing (50) is formed in the round cross-section, so that the base body (26) is displaceable in the second opening (24).

5. Fastening system (2) according to one of the preceding claims, further comprising a plurality of securing elements (68) which are designed to secure the base body to the holding elements (6, 70, 74, 76) in the axial direction.

6. Fastening system (2) according to claim 5, wherein the securing elements (68) are designed to be arranged in the axial direction directly in front of and behind the holding elements (6, 70, 74, 76) and to be connected to the base body (26).

7. Fastening system (2) according to claim 1 or 2, wherein the at least one fastening element (54) has a radial recess (56) complementary to the base body (26) and which can be plugged radially from the outside onto the base body (26), and wherein the at least one recess (56) has a second toothing (60) complementary to the first toothing (50).

8. Fastening system (2) according to claim 7, wherein the base body (26) has on at least one of the radial edge sections a longitudinally extending first securing groove (52) which corresponds to a second securing groove (62) in the recess (56) of the fastening element (54), and further comprising a locking pin (66) which is shaped complementarily to a safety opening that is formed by the first securing groove (52) and the second securing groove (62) aligned therewith so that it fixes the fastening element (54) and the base body (26).

9. Fastening system (2) according to one of the preceding claims, wherein the first position compensation bushing (18) and the second position compensation bushing (22) each have a circumferential collar (32, 34) on which a peripheral gearing (36) can be inserted to engage a tool.

10. Aircraft (78) comprising a fuselage (80) with a fuselage structure (4) and at least one component (82) which is fastened to the fuselage structure (4) by means of a fastening system (2) according to one of claims 1 to 9.

11. Aircraft (78) according to claim 10, wherein the component (82) is a passenger service unit or an overhead storage compartment.

12. Aircraft (78) according to claim 10 or 11, wherein the fuselage (80) has a longitudinal axis, a right side and a left side, and wherein along a substantial part of the right side and the left side of the fuselage (80) at least one base body (26) is held on the fuselage structure (4) parallel to the longitudinal axis.

13. Aircraft (78) according to claim 12, wherein at least two base bodies (26) spaced apart from one another are arranged parallel to the longitudinal axis on the right side and the left side.