GB2538704A

GB2538704A - An aircraft raceway and method of manufacture

Info

Publication number: GB2538704A
Application number: GB1508511.1A
Authority: GB
Inventors: Blanchard Jack
Original assignee: Airbus Operations Ltd
Current assignee: Airbus Operations Ltd
Priority date: 2015-05-18
Filing date: 2015-05-18
Publication date: 2016-11-30
Also published as: GB201508511D0

Abstract

An aircraft cable raceway (108, figure 3a) comprising a body (110) defining at least one raceway channel 132, the body being constructed from a polymer material 136 being at least partially covered by an electrically conductive outer layer 138. Preferably the electrically conductive layer shields the cables from interference and applied as an electrically conductive spray. The electrically conductive layer may be formed from aluminium, copper, steel, titanium, or graphene, and may be covered in a layer of non-abrasive material. The polymer material may be a plastic such as PEEK (polyether ether ketone), PAEK (polyaryletherketone), PPS (polyphenylene sulfide), or nylon, and preferably allows the body to be flexible. A method for manufacturing an aircraft raceway is also detailed, comprising; forming a raceway body from a polymer material and at least partially covering the raceway body in a layer of an electrically conductive material (such as aluminum).

Description

An aircraft raceway and method of manufacture FIELD OF THE INVENTION [0001] The present invention relates to an aircraft raceway. The present invention also relates to a method of manufacturing an aircraft raceway.

BACKGROUND OF THE INVENTION

[0002] Aircraft raceways are known in the art. Known raceways comprise a series of one or more adjacent U-shaped channels. The channels are formed from a prismatic body having an elongate, flat base with a plurality of walls projecting therefrom. Data and / or power wires are run along the channels from point to point in an aircraft. The raceways primarily protect the cables from mechanical damage. The raceways form a continuous elongate cable support seating at least a substantial part of the length of the or each cable. Known raceways are typically constructed from extruded aluminium sections, which offer ease of manufacture, a light weight, mechanical shielding and shielding from electromagnetic interference (EMI), specifically radio frequency interference (RFD.

[0003] The cables are secured in the raceways by a variety of methods, most commonly harpoon clamps which extend through the raceway base, through the cable bundle and clamp the bundle to the base in tension.

[0004] A known cable raceway 10 is shown in Figure 1. The raceway 10 comprises a prismatic body 12 having a section profile 14. The section profile 14 has a flat base portion 16 which forms a planar base of the raceway 10. The base portion has an underside 18 and a channel side 19. Extending normal to the base portion 16 from the channel side 19 and at opposite edges there are provide two sidewalls 20, 22 having free ends 24, 26. Between the sidewalls 20, 22 there is provided an intermediate wall 28 having a free end 30. The base 16, sidewall 20 and intermediate wall 28 form a first channel 32. The base 16, sidewall 22 and intermediate wall 28 form a second channel 34.

100051 The body 12 is constructed entirely from extruded aluminium.

100061 There are various problems with known cable raceways. Aluminium is relatively inflexible, and as such cannot easily be deformed to meet curved paths. Adjacent sections of raceway can be used to guide wires around curved paths, but gaps often appear between adjacent sections where curvature exists.

[0007] Although aluminium is a light metal, it is still relatively dense for the application in question. Reduction in aircraft mass could be achieved by reduction in the mass of the raceways.

SUMMARY OF THE INVENTION

[0008] A first aspect of the invention provides an aircraft cable raceway comprising a body defining at least one raceway channel, the body being constructed from a plastics material being at least partially covered by an electrically conductive outer layer.

[0009] The at least one raceway channel may be covered by the electrically conductive outer layer and at least part of the body may not be covered by the electrically conductive outer layer. Therefore, the weight may be minimised.

[0010] The electrically conductive outer layer may be a coating on the body. The electrically conductive outer layer may be an applied electrically conductive spray.

[0011] The electrically conductive outer layer may form a continuous layer along the length of the body. This provides for protecting one or more cables from electromagnetic hazards and radio frequency interference.

[0012] The body may define at least two raceway channels, wherein at least one of the raceway channels may be coated by the electrically conductive outer layer and at least one of the raceway channels may be, at least in part, not coated by the electrically conductive outer layer.

[0013] The polymer material may be selected from one of PEEK (polyether ether ketone), polyaryletherketone (PAEK), PPS (Polyphenylene sulfide), or Nylon.

[0014] The body may be flexible. [0015] The body may be resilient.

[0016] The aircraft cable raceway may further comprising a layer of non-abrasive material at least partially covering die electrically conductive outer layer.

[0017] The layer of non-abrasive material may cover at least one raceway channel.

[0018] The electrically conductive outer layer may be a first outer layer. The aircraft cable raceway may further comprise a second outer layer.

[0019] The electrically conductive outer layer may comprise a layer of metallic material.

[0020] The layer of metallic material may be formed from one of aluminium, copper, steel or titanium.

[0021] The electrically conductive outer layer may comprise a layer of graphene.

[0022] According to one aspect of the invention, there is provided a vehicle comprising an aircraft cable raceway in accordance with the abovementioned.

[0023] According to one aspect of the invention, there is provided a method of manufacturing an aircraft raceway, comprising the steps of: forming a raceway body from a plastics material, the raceway body comprising at least one channel, and at least partially coating the raceway body in a layer of an electrically conductive material.

[0024] The method may further comprise at least partially covering the layer of electrically conductive material with a layer of non-abrasive material.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Embodiments of the invention will now be described with reference to the accompanying drawings, in which: [0026] Figure 1 is a perspective view of a prior art cable raceway in accordance with the present invention; [0027] Figure 2 is a plan view of an aircraft comprising a raceway according to the present invention; [0028] Figure 3a is a perspective view of a cable raceway in accordance with the present invention; [0029] Figure 3b is a perspective view of the cable raceway of Figure 3a cut through plane "b/c"; [0030] Figure 3c is a section view of the cable raceway of Figure 3a through plane "b/c"; [0031] Figure 3d is a perspective section view of the cable raceway of Figure 3a through plane "d"; [0032] Figures 4a and 4b are flow diagrams of methods of manufacture in accordance with the present invention.

DETAILED DESCRIPTION OF EMBODIMENT(S)

[0033] Referring to Figure 2, a passenger aircraft 100 (also known as an airliner) comprises a fuselage 102, a port wing 104 and a starboard wing 106. Throughout the fuselage 102 and wings 104, 106 cables need to be routed for various reasons. Data and control signals need to be transmitted throughout the aircraft, as well as power to power the various electrical systems on board.

[0034] Referring to Figure 3a, a raceway 108 according to the present invention is shown, which is provided in the aircraft 100, and may extend through the fuselage 102 and / or wings 104, 106. The raceway 108 is the same basic shape as the prior art raceway 10 and comprises a prismatic body 110 having a section profile 112. The section profile 112 has a flat base portion 114 which forms a planar base of the raceway 108. The base portion has an underside 116 and a channel side 118. Extending normal to the base portion 114 from the channel side 118 and at opposite edges there are provide two sidewalls 120, 122 having free ends 124, 126. Between the sidewalls 120, 122 there is provided an intermediate wall 128 having a free end 130. The base 114, sidewall 120 and intermediate wall 128 form a first channel 132. The base 114, sidewall 122 and intermediate wall 128 form a second channel 134.

[0035] Referring to Figure 3d, a first circular through-bore 140 is provided in the base portion 114 in the first channel 132. A second circular through-bore 142 is provided in the base portion 114 in the second channel 134. The bores 140, 142 are positioned in the centres of the channels.

[0036] Referring to Figure 3b, a cut section of the raceway 108 is shown. Section views are shown in Figures 3c and 3d. The raceway 108 comprises a body 136 made from a polymer material. The material from which the body is constructed in this embodiment is PEEK (polyether ether ketone). It will be understood that the polymer material is not limited thereto. The material from which the body is constructed may be another plastics material, which may be in the polyaryletherketone (PAEK) family such as PEKK (polyether ketone ketone). Alternative polymers such as PPS (Polyphenylene sulfide) may be used as the material to form the body. The body 136 may be formed from an elastotner. Nylon may be used.

[0037] The body 136 is a prismatic profile and defines the section profile 112 having the base portion 114. sidewalls 120, 122 and the intermediate wall 128.

[0038] The raceway 108 comprises a layer 138 of a metallic material, which in this embodiment is aluminium, but is not limited thereto. For example, the layer 138 of a metallic material may be copper, steel, titanium or other metallic materials. The layer 138 of a metallic material acts as an electrically conductive outer layer with a layer of an electrically conductive material. In an alternative embodiment, the raceway 108 comprises a layer of graphene acting as a layer of an electrically conductive material. Such an arrangement of the raceway 108 with the layer of graphene has a corresponding arrangement to the raceway 108 with the layer 138 of a metallic material as described in detail herein.

[0039] The layer 138 coats the entire body 136. Referring to Figures 3c and 3d, the layer 138 coats the outer and inner surfaces of the body 136, including the inner surface of the bores 140, 142.

[0040] A layer 160 of a non-abrasive material is applied to an outer surface of the layer 138 of metallic material. The layer 138 of metallic material acts as an electrically conductive outer layer. The layer 160 of non-abrasive material acts as a protective layer over the electrically conductive outer layer. The layer 160 of nonabrasive material is formed from, for example, Nylon or PTFE. The layer 160 of nonabrasive material is a coating. Direct contact between the layer 138 of metallic material and cables received in the channel 132 is prevented. The layer 160 of nonabrasive material may be applied in the channel 132 only.

[0041] Referring to Figure 3d, a bundle of cables 144 is shown. The bundle 144 comprises a plurality of individual cables 146. The bundle 144 is contained within the channel 132. The bundle 144 is secured in the channel 132 by a harpoon clip 148 having a head 150 with opposing resilient wings 152 at a first end, and a retaining flange 154 at a second end. In use, the bundle 144 is placed in the channel 132, and the harpoon clip 148 inserted through the bundle, and through the bore 140 to retain the cables 146.

[0042] In use, the raceway 108 is flexible, and has a high strain-to-failure characteristic of the polymeric body 136. The metallic layer 138 provides the mechanical shielding and shielding from electromagnetic interference (EMI), specifically radio frequency interference (RFI). Therefore the raceway 108 fulfils the requirements of the prior art, whilst allowing cables to run in curved paths more easily.

[0043] Referring to Figure 4a, a first method of making the raceway 108 is described.

[0044] At step 200, the body 136 is formed. In the present embodiment the body 136 is extruded by a method known in the art. Alternatively, the body 136 is formed by moulding or machining.

[0045] At step 202 the resulting body is metal sprayed with the layer 138 to form the raceway 108. Alternative means of forming the layer 138 may be used at step 202. For example, alternatively, the step 202 may be an electroplating step.

[0046] Referring to Figure 4b, a second method of making the raceway 108 is described.

[0047] At step 200. the body 136 is extruded by a method known in the art. At step 202 the resulting body is electroplated with a seed layer of metallic material. At step 204, the layer 138 is built up using metal spraying. The use of a seed layer makes sure that the layer 138 properly adheres to the body 136.

[0048] Alternative embodiments are possible. In one embodiment, the body 136 is formed as described above, and the layer 138 of metallic material is formed separately. In this embodiment the layer 138 may be formed by extruding, for example. The layer 138 is then applied to the body 136. In another such embodiment, the layer 138 of metallic material is a metallic mesh applied to the body 136. In one embodiment, the body 136 is partially coated with metallic material. In one such embodiment, just the inner surfaces of the channels is coated. In another such embodiment, one of the channels is coated with the metallic layer and another of the channels is not coated with a metallic layer. Alternatively, different channels may be coated with different metallic layers.

[0049] Although the invention has been described above with reference to one or more preferred embodiments, it will be appreciated that various changes or modifications may be made without departing from the scope of the invention as defined in the appended claims.

Claims

CLAIMS1. An aircraft cable raceway comprising a body defining at least one raceway channel, the body being constructed from a polymer material being at least partially covered by an electrically conductive outer layer.
2. The aircraft cable raceway according to claim 1, wherein the at least one raceway channel is covered by the electrically conductive outer layer and at least part of the body is not covered by the electrically conductive outer layer.
3. The aircraft cable raceway according to claim 1 or claim 2, wherein the electrically conductive outer layer is a coating on the body.
4. The aircraft cable raceway according to claim 3, wherein the electrically conductive outer layer is an applied electrically conductive spray.
5. The aircraft cable raceway according to any one of the preceding claims.wherein the electrically conductive outer layer forms a continuous layer along the length of the body.
6. The aircraft cable raceway according to any one of the preceding claims, wherein the body defines at least two raceway channels, wherein at least one of the raceway channels is coated by the electrically conductive outer layer and at least one of the raceway channels is at least in part not coated by the electrically conductive outer layer.
7. The aircraft cable raceway according to any one of the preceding claims, wherein the polymer material is selected from one of PEEK (polyether ether ketone). polyaryletherketone (PAEK). PPS (Polyphenylene sulfide). or Nylon.
8. The aircraft cable raceway according to any one of the preceding claims, wherein the body is flexible.
9. The aircraft cable raceway according to any one of the preceding claims, wherein the body is resilient.
10. The aircraft cable raceway according to any one of the preceding claims, further comprising a layer of non-abrasive material at least partially covering the electrically conductive outer layer.
11. The aircraft cable raceway according to claim 10, wherein the layer of nonabrasive material covers at least one raceway channel.
12. The aircraft cable raceway according to any one of the preceding claims, wherein the electrically conductive outer layer is a first outer layer, the aircraft cable raceway further comprising a second outer layer.
13. The aircraft cable raceway according to any one of the preceding claims, wherein the electrically conductive outer layer comprises a layer of metallic material.
14. The aircraft cable raceway according to claim 13, wherein the layer of metallic material is formed from one of aluminium, copper, steel or titanium.
15. The aircraft cable raceway according to any one of the preceding claims, wherein the electrically conductive outer layer comprises a layer of graphene.
16. A vehicle comprising the aircraft cable raceway according to any one of the preceding claims.
17. A method of manufacturing an aircraft raceway, comprising the steps of: forming a raceway body from a polymer material, the raceway body comprising at least one channel; and at least partially covering the raceway body in a layer of an electrically conductive material.
18. A method according to claim 17, further comprising at least partially covering the layer of electrically conductive material with a layer of non-abrasive material.