Nut assembly

Abstract

A nut assembly secured to an aircraft structure includes a nut sleeve having a hollow body and a plurality of arms extending away from the body from one end of the body, the body and the plurality of arms extending perpendicular to each other. Wherein the nut assembly further comprises: a shim between the nut sleeve and the aircraft structure, secured to the plurality of arms of the nut sleeve by fasteners, where the shim has an aperture coaxial with the body; and a plurality of fasteners that secure the shim to the aircraft structure. The nut sleeve is for mating engagement with a fastener of an outer structure to assemble the outer structure. According to the nut assembly, the loaded condition of all parts in the nut assembly can be improved, the service life of the nut assembly is prolonged, and the risk that the nut assembly falls off accidentally is reduced.

Description

Technical Field

[0001] The utility model relates to the field of aircraft structure connection, and in particular to a nut assembly. Background Art

[0002] Aircraft contain external structures, such as fairing panels, that need to be externally connected to the fuselage structure. Since the external structure is typically assembled to the fuselage structure after it is fully assembled, fasteners such as bracket nuts must be pre-installed within the fuselage structure. Fasteners, such as bolts, are then used to mate and engage the fasteners to assemble the external structure and fuselage structure. Before installing the fasteners, holes must be drilled based on the specific locations where the external structure will connect to the fuselage structure. In practice, small rivets are often used to secure fasteners to the fuselage structure. Generally speaking, due to their limited stress tolerance, these rivets are limited to connecting single-layer components, excluding the fasteners. However, since the multi-layer fuselage structure is often already assembled when the holes are drilled, the small rivets can only penetrate the multi-layer structure to secure the fasteners. This also forces the small rivets to be installed side by side with other fuselage structure fasteners. This arrangement does not meet conventional installation requirements, causing the rivets to be overloaded. In addition, since the rivets and other fuselage structural fasteners are installed side by side, they are easily subjected to loads transmitted from the fuselage structure, which can easily shorten their service life.

[0003] There are methods that replace rivet fastening with adhesive fastening. Specifically, the fastener is bonded to the hole used to insert the external structure's fastener. This method eliminates the problem of excessive load on the rivet. However, due to the frequent disassembly and maintenance of the external structure, the fastener must repeatedly withstand the insertion and withdrawal of the external structure's fastener. Over time, this load can easily weaken the bond of the fastener, leading to its fallout.

[0004] Therefore, there is a need to provide an improved nut assembly that can solve the above-mentioned problems and defects in the prior art. Utility Model Content

[0005] The purpose of the utility model is to provide a nut assembly, which can improve the load conditions of various components in the nut assembly, increase the service life of the nut assembly, and reduce the risk of accidental falling off.

[0006] According to the present invention, a nut assembly is provided for securing to an aircraft structure. The nut assembly comprises: a nut sleeve having a main body with a central axis and a plurality of arms extending from one end of the main body away from the main body, the plurality of arms extending perpendicularly to the central axis of the main body; and a nut disposed within the nut sleeve and having an internal thread. The nut assembly further comprises: a washer disposed between the nut sleeve and the aircraft structure and secured to the plurality of arms of the nut sleeve by fasteners, wherein the fasteners do not extend into the aircraft structure and wherein the washer has an aperture; and a plurality of fasteners securing the washer to the aircraft structure. The nut sleeve is configured to mate with fasteners of an external structure to assemble the external structure. The addition of the washer allows fasteners, such as rivets, used to secure the nut sleeve to only connect the nut sleeve and the washer. This allows for the installation of small rivets suitable for the nut sleeve and reduces the load on the rivets. Furthermore, since the fastener is no longer secured to the aircraft structure, it is not subject to loads transmitted through the aircraft structure, significantly reducing the risk of accidental damage.

[0007] According to another aspect of the present disclosure, the plurality of fixings are spaced apart from the plurality of arms of the nut sleeve, wherein a radial distance from each of the plurality of fixings to the body of the nut sleeve is not less than 1.5 times a radial length of one of the plurality of arms of the nut sleeve.

[0008] According to another aspect of the present disclosure, the nut sleeve is centrally positioned on the gasket, wherein the gasket is shaped as a rectangle, an oval or a circle. Of course, the present invention is not limited thereto, and the gasket can adopt any plane shape suitable for installing the nut sleeve.

[0009] According to another aspect of the present disclosure, the surface of the washer abutting the nut sleeve is flat, while the surface of the washer abutting the aircraft structure has a shape that conforms to the surface of the aircraft structure.

[0010] According to another aspect of the present disclosure, the fastener includes a rivet, and the fixing member includes a bolt.

[0011] According to another aspect of the present disclosure, the gasket is formed of an alloy material or a fiber polymer reinforced material. Preferably, the gasket is made of the same material as the aircraft structure on which it is installed.

[0012] According to another aspect of the present disclosure, the nut assembly further comprises a screw rod, wherein the screw rod has external threads and is threadedly engaged with the nut sleeve.

[0013] In a preferred embodiment of the present invention, the main body of the nut sleeve has a raised ring portion at the end where the multiple arms are provided. A nut is placed in the raised ring portion, and the internal threads of the nut mate with the external threads of the screw. The screw is inserted into the nut sleeve by screwing the nut together. Alternative embodiments are also contemplated in which the main body of the nut sleeve has internal threads that mate with the external threads of the screw, or the nut is integrally formed in the main body of the nut sleeve, allowing the screw to be screwed directly into the nut sleeve.

[0014] According to another aspect of the present disclosure, each of the plurality of arms of the nut sleeve has a recess in which the fastener is disposed. However, alternative embodiments may also contemplate that the plurality of arms of the nut sleeve have flat surfaces.

[0015] The present invention incorporates a gasket between the nut sleeve and the aircraft structure, connects the two using fasteners, and secures the gasket to the multi-layered aircraft structure using stronger fasteners. This secures the nut sleeve to the aircraft structure while also minimizing the load borne by the fasteners connecting the nut sleeve. Furthermore, since the fasteners are not connected to the aircraft structure, they avoid bearing loads transmitted through the aircraft structure, thereby optimizing the load conditions on the various components of the nut structure and significantly extending its service life.

[0016] This summary is provided to introduce concepts in a simplified form that will be further described in the detailed description below. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. Other aspects and advantages of the present invention will become apparent from the following detailed description of the embodiments and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] For a more complete understanding of the present disclosure, reference may be made to the following description of exemplary embodiments considered in conjunction with the accompanying drawings. The accompanying drawings are not intended to limit the present disclosure to the specific embodiments depicted therein and are not necessarily to scale. In the drawings:

[0018] Figure 1 It is a cross-sectional view of a nut assembly according to a preferred embodiment of the present invention.

[0019] Reference Signs List

[0020] 100 nut assembly

[0021] 200 aircraft structure

[0022] 300 aircraft external structure

[0023] 1 nut sleeve

[0024] 11 main body

[0025] 12 arms

[0026] 13 convex ring part

[0027] 14 recesses

[0028] 15 First End

[0029] 16 Second end

[0030] 2 gaskets

[0031] 21 holes

[0032] 3 Fasteners

[0033] 4 fixings

[0034] 5 nuts

[0035] 6 screw

[0036] X-axis direction

[0037] Y radial direction

[0038] A. The central axis of the main body of the nut sleeve

[0039] l1 Radial distance of the nut sleeve arm

[0040] l2 Radial distance from the fixing to the main body

[0041] l3 Radial length of the gasket

[0042] l4 Radial projection length of the nut sleeve DETAILED DESCRIPTION

[0043] The following description of the present invention with reference to the accompanying drawings shows specific embodiments in which the present invention can be put into practice. The embodiments are intended to fully describe the various aspects of the present invention in detail so that those skilled in the art can implement the present invention. Other embodiments may be utilized and may be changed without departing from the scope of the present invention. Therefore, the following description of the specific embodiments should not be considered restrictive. The scope of the present invention is limited only by the appended claims and the full range of equivalents covered by the claims. The same reference numerals are used throughout all drawings and the specific embodiments to refer to the same or similar parts.

[0044] Herein, the main body 11 of the nut sleeve 1 is a rotating part having a central axis A. The direction X is the axial direction, which is coaxial with the central axis A of the main body 11 of the nut sleeve 1. Figure 1 direction Y is the radial direction, which is perpendicular to the axial direction X.

[0045] For clarity, when multiple identical components appear (eg, arm 12, fastener 3, retainer 4), only one of the components is labeled.

[0046] Figure 1 A nut assembly 100 according to a preferred embodiment of the present invention is shown for assembling an aircraft structure 200 with an external aircraft structure 300. The aircraft structure 200 comprises a multi-layer structure, with two layers being shown in this preferred embodiment. The nut assembly 100 generally comprises a nut sleeve 1 secured against the aircraft structure 200 by a washer 2 and may also include a screw 6 threadedly inserted into the nut sleeve 1, passing through the external aircraft structure 300 and the aircraft structure 200, respectively.

[0047] The nut sleeve 1 has a main body 11 which is hollow and has a first end 15 and a second end 16 opposite to each other. The main body 11 is closed at its first end 15 and open at its second end 16. A plurality of arms 12 are also provided to connect the nut sleeve 1 to the washer 2. These arms 12 extend from the second end of the main body 11 of the nut sleeve 1 in a radial direction Y away from the main body 11, i.e. each of the plurality of arms 12 extends perpendicularly to the central axis A of the main body 11. In this preferred embodiment, two arms 12 arranged opposite to each other are provided, but a greater number of arms 12 can also be envisaged in alternative embodiments to make the connection between the nut sleeve 1 and the washer 2 more stable. Each of the plurality of arms 12 is preferably as Figure 1 The recess 14 is shown as being provided to facilitate placement of the fastener 3 for connecting the nut sleeve 1 to the washer 2, but alternative embodiments may also envisage providing the arms 12 with flat surfaces.

[0048] The nut assembly 100 also includes a washer 2, which is positioned between the nut sleeve 1 and the aircraft structure 200. The washer 2 is connected to the multiple arms 12 of the nut sleeve 1 by a plurality of fasteners 3, and is connected to the aircraft structure 200 by a plurality of fixing elements 4. The washer 2 has an aperture 21 to allow the threaded rod 6 to pass through. The nut sleeve 1 is preferably centrally positioned on the washer 2, and the washer 2 can have a shape and size suitable for mounting the nut sleeve 1, such as rectangular, oval, circular, or other shapes and sizes. In other words, the radial length of the washer 2 is greater than the radial projection length of the nut sleeve 1 to facilitate mounting of the fasteners 3 and fixing elements 4, but is preferably no greater than twice the radial projection length of the nut sleeve 1 to prevent the washer 2 from being too large and thus inconvenient to mount. The washer 2 is a sheet material with an axial height significantly less than its radial width, and is formed from, for example, an alloy material or a fiber-reinforced polymer material, preferably the same material as the aircraft structure 200 to which the nut assembly 100 is mounted.

[0049] Preferably, different washers 2 can be selected according to different aircraft structures 200. For example, if the nut sleeve 1 is to be installed on an aircraft structure 200 with a curved surface, the washer 2 can be selected so that its surface adjacent to the nut sleeve 1 is flat, while the surface adjacent to the aircraft structure 200 has a corresponding curvature. If the nut sleeve 1 is to be installed on an aircraft structure 200 with a flat surface, the washer 2 can be selected so that both its opposite surfaces are flat. In this way, the same nut sleeve 1 can be installed on various aircraft structures 200 with different shapes without changing the structure of the nut sleeve 1, thereby significantly reducing the manufacturing and installation costs of the nut assembly 100.

[0050] like Figure 1 As shown, the fasteners 3 only connect the nut sleeve 1 and the gasket 2, while the fixing members 4 pass through the aircraft structure 200 having a multi-layer structure to connect it with the gasket 2. Therefore, the size of the fixing members 4 is significantly larger than the fasteners 3, and is preferably arranged on the gasket 2 to be farther away from the nut sleeve 1 than each of the fasteners 3, but not too far away from the nut sleeve 1 to prevent the gasket 2 from being fixed to the aircraft structure 200 with insufficient stability. Specifically, the plurality of fixing members 4 are spaced apart from the plurality of arms 12 of the nut sleeve 1, and the radial distance l2 of each of the plurality of fixing members 4 to the main body 11 of the nut sleeve 1 is not less than 1.5 times the radial length l1 of one of the plurality of arms 12 of the nut sleeve 1. As shown in FIG. Figure 1 As shown, the plurality of fasteners 3 and the plurality of fixing elements 4 can be arranged collinearly. However, the present invention is not limited thereto, and any arrangement that facilitates the fixing of the nut sleeve 1 and the gasket 2 can be employed. For example, in an alternative embodiment, the plurality of fixing elements 4 can be arranged in a ring pattern on the gasket 2, and each fixing element 4 can be evenly spaced.

[0051] Preferably, the fastener 3 may be a rivet, and the fixing member 4 may be a bolt.

[0052] The nut assembly 100 may further comprise a screw 6 for securing the aircraft external structure 300 to the aircraft structure 200. The screw 6 is generally threadedly connected to the nut sleeve 1. Therefore, in the preferred embodiment, a collar 13 is provided at the second end 16 of the body 11 of the nut sleeve 1, in which collar 13 is placed a nut 5, the nut 5 and the screw 6 having matching internal and external threads. However, alternative embodiments are also conceivable, in which, instead of providing an additional collar 13 and a nut 5, the nut sleeve 1 is provided with an internal thread and is dimensioned to be threadedly engaged with the screw 6 having matching external threads; or the nut 5 is integrally formed in the body 11 of the nut sleeve 1.

[0053] The steps for fastening the aircraft outer structure 300 to the aircraft structure 200 using the nut assembly 100 are as follows:

[0054] - drilling holes for a plurality of fixing elements 4 and screws 6 at the locations of the aircraft structure 200 where the nut assembly 100 is to be installed;

[0055] If the nut assembly 100 having the collar 13 and the nut 5 is used, the nut 5 is placed into the collar 13;

[0056] - Use multiple fasteners 3 to fix the nut sleeve 1 and the washer 2 together;

[0057] - Using a plurality of fixing elements 4 to fix the gasket 2 to the aircraft structure 200 , thereby completing the fixing of the nut sleeve 1 to the aircraft structure 200 ;

[0058] - Screw the screw 6 through the aircraft outer structure 300 and insert it into the nut sleeve 1 .

[0059] If the aircraft outer structure 300 needs to be disassembled for maintenance, the screw 6 can be screwed out of the nut sleeve 1 .

[0060] The nut assembly of the present invention optimizes the load condition of the fastener while ensuring that the nut sleeve is firmly fixed by arranging a gasket between the nut sleeve and the aircraft structure, and configuring the fastener for the nut sleeve to only connect the nut sleeve and the gasket, thereby solving the problems in the prior art of unfavorable load condition caused by fasteners penetrating the multi-layer fuselage structure, or unstable fixation causing easy falling off during use.

[0061] As used herein, the terms "comprises," "comprising," "including," "having," or any further variations thereof, are intended to cover a non-exclusive inclusion. For example, a method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such method, article, or apparatus.

[0062] The present invention is not limited to the above-described embodiments, which are merely illustrative and non-restrictive. Those skilled in the art, informed by the present invention, may make any possible changes and modifications without departing from the spirit of the present invention and the scope of protection of the claims. Therefore, any modifications, equivalent variations, and modifications made to the above-described embodiments in accordance with the technical essence of the present invention that do not depart from the technical solution of the present invention shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. A nut assembly, secured to an aircraft structure, comprising: A nut sleeve having a main body with a central axis and a plurality of arms extending away from the main body from one end of the main body, the plurality of arms extending perpendicular to the central axis of the main body, a nut, the nut being in the nut sleeve and having an internal thread, Characterized in that, the nut assembly further comprises: a washer positioned between the nut sleeve and the aircraft structure, secured to the plurality of arms of the nut sleeve by fasteners that do not extend into the aircraft structure, wherein the washer has an aperture; and A plurality of fasteners secure the spacer to the aircraft structure.

2. The nut assembly according to claim 1, wherein: The plurality of fixings are spaced apart from the plurality of arms of the nut sleeve, wherein a radial distance from each of the plurality of fixings to the body of the nut sleeve is not less than 1.5 times a radial length of one of the plurality of arms of the nut sleeve.

3. The nut assembly according to claim 1 or 2, characterized in that: The nut sleeve is centrally positioned on the washer, wherein the washer is rectangular, oval or circular in shape.

4. The nut assembly according to claim 1 or 2, characterized in that: The surface of the washer abutting the nut sleeve is flat, while the surface of the washer abutting the aircraft structure has a shape adapted to the surface of the aircraft structure.

5. The nut assembly according to claim 1 or 2, characterized in that: The fastener comprises a rivet, and the fixing member comprises a bolt.

6. The nut assembly according to claim 1 or 2, characterized in that: The gasket is formed of an alloy material or a fiber polymer reinforced material.

7. The nut assembly according to claim 1, wherein: The nut assembly further comprises a screw, wherein the screw is externally threaded and threadably engaged with the nut sleeve.

8. The nut assembly according to claim 7, wherein: The main body of the nut sleeve has a raised ring portion at the end where the plurality of arms are provided, wherein the nut is placed in the raised ring portion, and the internal thread of the nut matches the external thread of the screw.

9. The nut assembly according to claim 7, wherein: The nut is integrally formed in the main body of the nut sleeve, and the internal thread of the nut matches the external thread of the screw.

10. The nut assembly according to claim 1 or 2, characterized in that: Each of the plurality of arms of the nut sleeve has a recess in which the fastener is disposed.

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