Field of the invention

[0001] The invention relates to a locking assembly for locking an aircraft interior structure, such as a galley, to an aircraft main support structure, such as a floor hard point, comprising:

a cylindrical adjustment bushing having a hollow cylindrical space, the adjustment bushing having an outer thread that engages an inner thread of a through- hole arranged in a fitting attachable to or part of the aircraft interior structure, wherein the adjustment bushing can be rotated around its centre line to adjust the height of the fitting in a Z-direction,

a cylindrical outer eccentric bushing inserted in the hollow cylindrical space of the adjustment bushing, the outer eccentric bushing having an eccentric longitudinal hollow cylindrical space whose centre line is placed at a distance from the centre line of the cylindrical outer eccentric bushing,

a cylindrical inner eccentric bushing inserted in the hollow cylindrical space of the outer eccentric bushing, the inner and outer eccentric bushings allowing adjustment of the fitting in a plane perpendicular to the Z-direction,

a locking bolt inserted in the hollow cylindrical space of the inner eccentric bushing, the locking bolt engaging the elongated projection to lock the assembly.

Background of the invention

[0002] Such a locking assembly is known from the German patent publication DE 10 2004 012 262. This patent publication describes how the above locking assembly can be conveniently used for adapting the height of the aircraft interior structure with respect to a floor hard point to which the locking assembly and the aircraft interior structure are to be connected.

[0003] The fore mentioned adjustment bushing allows adjustment of the fitting attachable to the aircraft interior structure in Z-direction, i.e. the direction in line with the elongated projection. Subsequently, the inner and outer eccentric bushings allow the fitting to be adjusted with respect to the projection in a plane perpendicular to the Z- direction, thus allowing the fitting and an aircraft interior structure attached thereto to be adjusted in a three-dimensional way, without needing any shim plates. After the aircraft interior structure is positioned, it can be secured by the locking bolt.

[0004] However, a disadvantage of the known locking assembly is that it is relatively hard to see for the person installing the aircraft interior structure if the desired adjustment height in Z-direction has been reached. The aforementioned person will have to set the height in Z-direction by way of trial and error.

[0005] Therefore, it is an object of the invention to provide an improved locking assembly that allows the person installing the aircraft interior structure to readily see, during installation, whether the desired height in Z-direction has been reached.

Summary of the invention

[0006] Thereto, the locking assembly according to the invention is characterized in that the adjustment bushing is provided with a visual indicator for indicating its relative position in Z-direction with respect to the fitting.

[0007] The visual indicator allow the person installing the aircraft interior structure to readily see whether the desired adjustment height in Z-direction has been arrived at.

[0008] It is noted that the locking assembly as disclosed in the German patent publication DE 10 2004 012 262 teaches the use of an additional ring (indicated by reference numeral 3 in the figures of the aforementioned patent publication) arranged over the outer thread of the adjustment bushing, which would block the view of the visual indicator. Part of the present inventive concept is that this additional ring can be omitted.

[0009] In a preferred embodiment, the visual indicator comprises a row of holes, preferably three holes, arranged in longitudinal direction in the outer thread of the adjustment bushing, wherein the visibility of the holes indicates the position of the adjustment bushing with respect to the fitting in Z-direction.

[0010] A preferred embodiment relates to a locking assembly, wherein the outer eccentric bushing is provided with an upper flange that is supported by the upper end of the adjustment bushing. The upper flange prevents the outer eccentric bushing from falling into the hollow cylindrical space of the adjustment bushing. [0011] Another embodiment concerns a locking assembly, wherein the outer eccentric bushing is provided with a visual indicator on or in its flange for indicating its relative rotational position with respect to the adjustment bushing. Thus, the person installing the assembly is able to quickly obtain visual information on the positioning of the outer eccentric bushing.

[0012] A further embodiment relates to a locking assembly, wherein the inner eccentric bushing is provided with an upper flange that is supported by the upper flange of the outer eccentric bushing. Analogously, the upper flange of the inner eccentric bushing prevents it from disappearing into the outer eccentric bushing.

[0013] An embodiment relates to a locking assembly, wherein the inner eccentric bushing is provided with a visual indicator on or in its flange for indicating its relative rotational position with respect to the adjustment bushing. Again, the person installing the assembly is enabled to obtain visual information on the positioning of the inner eccentric bushing with minimal effort.

[0014] In a further embodiment, the head of the locking bolt is supported by the upper flange of the inner eccentric bushing. The upper flange can be conveniently used to support the locking bolt and, when the locking bolt is tightened, to transfer the compressive forces of the locking bolt to the other locking assembly parts.

[0015] The visual indicator can advantageously comprise a recess arranged in the upper flange. This recess can additionally be used for rotating the respective eccentric bushing by means of a screw driver that can be inserted in the recess.

[0016] In an embodiment, the lower end of the adjustment bushing is supported by a support member of the elongated projection. Such a support member is often used on aircraft floor hard points, providing a convenient support location for the adjustment bushing.

[0017] Optionally, a low- friction layer, for instance in the form of a washer, for example made of nylon, can be arranged on the elongated projection, below the lower end of the adjustment bushing to support the adjustment bushing. The low-friction layer prevents the occurrence of concentrated loads on the support member or elongated projection, or the lower end of the adjustment bushing and allows the adjustment bushing to be smoothly rotated with respect to the support member or elongated projection. [0018] Additionally, a steel ring can be arranged on the elongated projection, below the lower end of the adjustment bushing to support the adjustment bushing or the low- friction layer. The steel ring provides a larger surface for supporting the lower end of the adjustment bushing.

[0019] The invention also relates to an aircraft comprising an aircraft interior structure, such as a galley, that is attached to an aircraft main support structure, such as a floor hard point, by using a locking assembly described above.

[0020] Furthermore, the invention relates to a method for locking an aircraft interior structure, such as a galley, to an aircraft main support structure comprising an elongated projection, such as a floor hard point, comprising the steps of:

arranging a cylindrical adjustment bushing having a hollow cylindrical space and an outer thread over the elongated projection of the aircraft main support structure until a lower end of the adjustment bushing is supported by a support member or support surface arranged on or near the elongated projection, causing the outer thread of the adjustment bushing to engage an inner thread of a through-hole of a fitting, that is attachable to the aircraft interior structure, and rotating the adjustment bushing around its longitudinal axis to achieve a desired height of the fitting in a Z-direction, wherein the adjustment bushing is provided with a visual indicator for indicating its relative position in Z-direction with respect to the fitting,

- inserting an outer eccentric bushing into the hollow cylindrical space of the adjustment bushing,

- inserting an inner eccentric bushing into the hollow cylindrical space in the outer eccentric bushing,

- inserting a locking bolt into the hollow cylindrical space in the inner eccentric bushing and causing the locking bolt to loosely engage the elongated projection, adjusting the position of the fitting in a direction comprised by the plane perpendicular to the Z-direction using the inner and outer eccentric bushings, causing the locking bolt to firmly engage the elongated projection in order to lock the assembly. Brief description of the drawings

[0021] An embodiment of a locking assembly according to the invention will by way of non-limiting example be described in detail with reference to the accompanying drawings. In the drawings:

[0022] Figure 1 shows an exploded view of an example of the locking assembly according to the invention, and

[0023] Figure 2 shows the embodiment shown in figure 1 in an assembled condition.

Detailed description of the invention

[0024] Figure 1 shows an exploded view of an exemplary embodiment of a locking assembly 16 according to the invention. The embodiment will be discussed in relation to the normal order of assembly. The aircraft interior structure, in this example having the form of a galley (the galley itself not being shown) is to be positioned on an aircraft main support structure in the form of an aircraft hard point on the aircraft floor, the hard point having an elongated projection 18 projecting downwards, into the floor, and having an inner screw thread for receiving a bolt 8 (see figure 2). The projection 18 is usually provided with a support member on top in the form of a bushing 9 to support the locking assembly 16 and the galley, and is provided with an O-ring seal to prevent damage to the bushing 9 during installation of the galley. The bushing 9 is substantially flush with the aircraft floor. The bushing 9 is preferably provided with a low-friction layer, for example a washer 5.

[0025] An adjustment bushing 4 for changing the height of the galley in the Z-direction as shown is then positioned over the bushing 9 until a lower end of the adjustment bushing is supported by the bushing 9. The adjustment bushing 4 has a generally cylindrical shape, with the longitudinal axis of the adjustment bushing 4 being aligned with the longitudinal axis of the projection 18. The adjustment bushing 4 is hollow, i.e. it has a hollow inner cylindrical space 15 that extends through the adjustment bushing 4 in longitudinal direction. The bolt 8 (see figure 2) is received in this cylindrical space 15.

[0026] The adjustment bushing 4 is provided with an outer screw thread so that it can be screwed into a through-hole 3 in a fitting 7 shown above the adjustment bushing 4, the through-hole 3 being provided with an inner screw thread. The fitting 7 can be attached to the galley or a similar "monument". The fitting 7 is then supported by the bushing 9 and the adjustment bushing 4. By rotating the adjustment bushing 4 the height of the fitting 7 with respect to the hard point projection 18 and the aircraft floor can be adjusted in Z-direction. The adjustment range is preferably 3 mm in each direction. The lower part of the adjustment bushing 4 comprises a hexagonal portion to facilitate rotation of the adjustment bushing 4 through the use of common-place tools, such as a wrench. After adjustment in Z-direction, the fitting 7 has to be adjusted in the plane perpendicular to the Z-direction, i.e. the plane extending essentially parallel to the aircraft floor, since the adjustment bushing 4 can still move over the projecting hard point 18 in this plane. The adjustment range in this plane is preferably +/- 1.5 mm in perpendicular directions comprised by this plane.

[0027] Thereto, a cylindrical outer eccentric bushing 2 is to be inserted from above into the hollow cylindrical space 15. The outer eccentric bushing 2 is also provided with a hollow cylindrical space S ₀ extending along the length of the cylindrical inner eccentric bushing 2. This space S ₀ is also intended to enclose the bolt 8 (see figure 2). However, the centre line of this hollow cylindrical space S ₀ is not aligned with the centre line of the cylindrical outer eccentric bushing 2 itself, but is placed at a certain distance (dl, not shown) there from. Therefore, the bushing 2 is called an "eccentric" bushing 2. Within the hollow cylindrical space S ₀ of the outer eccentric bushing 2 a similar, (cylindrical) inner eccentric bushing 1 is to be inserted. This inner eccentric bushing 1 is also provided with a hollow cylindrical space Si whose centre line is offset with respect to the centre line of the cylindrical inner eccentric bushing 1 itself over a distance (d2, not shown). The outer eccentric bushing 2 is provided with an upper flange 10 that supports the inner eccentric bushing 1 and prevents the outer eccentric bushing 2 from falling into the hollow cylindrical space 15. The inner eccentric bushing 1 is analogously provided with an upper flange 11 to prevent the inner eccentric bushing 1 from falling into the outer eccentric bushing 2 (and, consequently, from disappearing into the hollow cylindrical space 15), and to support the locking bolt 8 (see figure 2). Note that during adjustment the bolt 8 extends through the inner eccentric bushing 1, outer eccentric bushing 2, adjustment bushing 4, washer 5 and O- ring 6 and loosely engages the inner screw thread of the projection 18 in order to allow adjustment.

[0028] Both flanges 10, 11 can be provided with visual position indicators 13, 14 so that the person installing the galley can see, from the outside, how the eccentric bushings 1, 2 are positioned, i.e. rotated, with respect to each other and how they are positioned with respect to the adjustment bushing 4. Such a visual position indicator 13, 14 can for example be formed by a small recess in the respective flange 10, 11. The adjustment bushing 4 is provided with a visual position indicator 17 according to the invention, for example embodied by a row of holes, such as three holes, the row of holes extending in longitudinal direction of the adjustment bushing 4, wherein the amount of holes visible to the person installing the galley indicates the position of the adjustment bushing 4 in Z-direction.

[0029] Figure 2 shows the embodiment shown in figure 1 in an assembled and locked condition. Figure 2 essentially shows the exploded-view assembly 16 as shown in figure 1 with the locking bolt 8 inserted into the hollow space Si of the inner eccentric bushing assembly 16 and firmly engaging the inner thread of the hard point projection 18 of the aircraft floor, thereby locking the position of the assembly's elements with respect to each other.

[0030] Further provided is a locking assembly 16 for locking an aircraft interior structure, such as a galley, to an aircraft main support structure, such as a floor hard point, comprising:

a cylindrical adjustment bushing 4 having a hollow cylindrical space 15 extending through the adjustment bushing 4 in longitudinal direction, the adjustment bushing 4 having an outer thread 12 that engages an inner thread of a through-hole 3 arranged in a fitting 7 attachable to or part of the aircraft interior structure, wherein the adjustment bushing 4 can be rotated around its centre line to adjust the height of the fitting 7 in a Z-direction,

a cylindrical outer eccentric bushing 2 inserted in the hollow cylindrical space 15 of the adjustment bushing 4, the outer eccentric bushing 2 having an eccentric longitudinal hollow cylindrical space S ₀ whose centre line is placed at a distance dl from the centre line of the cylindrical outer eccentric bushing 2,

a cylindrical inner eccentric bushing 1 inserted in the hollow cylindrical space

S ₀ of the outer eccentric bushing 2, the outer eccentric bushing 2 having an eccentric longitudinal hollow cylindrical space Si whose centre line is placed at a distance d2 from the centre line of the cylindrical inner eccentric bushing 1, the inner and outer eccentric bushings 1, 2 allowing adjustment of the fitting 7 in a plane perpendicular to the Z-direction, a locking bolt 8 inserted in the hollow cylindrical space Si of the inner eccentric bushing 1, the locking bolt 8 engaging an elongated projection 18 of the aircraft main support structure 9, 18 to lock the assembly 16. This locking assembly 16 may comprise a low-friction layer, for instance in the form of a washer, for example made of nylon, which is arranged on the elongated projection 18, below the lower end of the adjustment bushing 4 to support the adjustment bushing 4. Furthermore, a steel ring 6 may be arranged on the elongated projection 18, below the lower end of the adjustment bushing 4 to support the adjustment bushing 4 or the low-friction layer 5.

[0031] Thus, the invention has been described by reference to the embodiment discussed above. It will be recognized that this embodiment is susceptible to various modifications and alternative forms well known to those of skill in the art without departing from the spirit and scope of the invention. Accordingly, although a specific embodiment has been described, this is an example only and is not limiting upon the scope of the invention.

Reference numerals

1. Inner eccentric bushing

2. Outer eccentric bushing

3. Through-hole in fitting

4. Adjustment bushing with outer thread

5. Washer

6. Ring

7. Fitting with threaded through-hole

8. Locking bolt

9. O-ring and bushing

10. Flange of outer eccentric bushing

11. Flange of inner eccentric bushing

12. Outer thread of adjustment bushing

13. Position indicator on outer adjustment bushing

14. Position indicator on inner adjustment bushing

15. Hollow cylindrical space in adjustment bushing

16. Locking assembly

17. Position indicator on adjustment bushing

18. Aircraft hard point projection provided with inner screw thread