WO2024115217A1

WO2024115217A1 - Support for cable harness rails

Info

Publication number: WO2024115217A1
Application number: PCT/EP2023/082673
Authority: WO
Inventors: Bastien PUERTOLAS; David JUPIN
Original assignee: Latelec
Priority date: 2022-11-30
Filing date: 2023-11-22
Publication date: 2024-06-06
Also published as: FR3142619A1

Abstract

The invention relates to a support (1) for holding at least one rail (6) of a cable harness, this holding support (1) being secured to a mounting bracket (5) and comprising at least two webs (2, 3) per rail, each web having a support surface for the cable harness, these webs being separated by a lacing space and connected to the bracket (5) by an attachment base. One of the webs, referred to as the outer web (2), comprises at least one blind bore, each of which has a bottom forming a plug, and the other webs, referred to as inner webs (3), comprise at least one through-hole.

Description

DESCRIPTION

ELECTRONIC HARNESS RAMPS SUPPORT

TECHNICAL AREA

The invention relates to a mechanical support for wiring ramps which allow rigid routing of electronic wiring harnesses, and more particularly electrical and optical harnesses. In particular the harnesses of electronic furniture, electrical cores and wiring routes in general of aircraft and satellites are intended to be installed and held on their ramps by such holding supports.

The invention also relates to a method of installing harness wiring on an avionics bay, these harnesses being routed by wiring ramps held by such holding supports.

In the aeronautical field in particular, complex cabling installations are carried out for electronic equipment such as furniture or avionics bays. These support supports optimize the space used by the cables and increase installation rates.

STATE OF THE TECHNIQUE

Generally speaking, the ramp supports are standard parts made of plastic material to which the metal tubes constituting the ramps are fixed by shrinking. These supports are also integral with an installation structure, all of the supports and ramp creating an architecture for routing the harnesses or cable strands. However, since the hooping is carried out by knotted links, the orientation of the hooping nodes must be considered to avoid being in contact with the cables and risking damaging them. Indeed, if the hoop node is in contact with the cables, it constitutes an extra thickness of the ramp which then deforms locally and induces tensions in the strand. The position of each hoop node is therefore checked before installing the harnesses. In addition, the working conditions and the space available can lead to injuries when making the hoop knots and therefore cause an increase in the duration of cabling installation.

Traditionally, each end of the ramp is held by a support located at a distance from the end. The ramp being metallic, a heat-shrinkable end piece is then installed on each end of the ramp, the purpose of this end piece is to protect the ramp by avoiding internal corrosion but also to protect the harness from friction against the ends of the ramp. In addition, the installation rules impose two shrinkages:

- a tightening of the strand on the end piece approximately 3 cm from the end of the ramp, and

- a hooping of the bundle of cables constituting the strand approximately 1cm from the end of the ramp.

The installation of the heat-shrinkable end piece with specific tools and the shrinking of the strand at the end of the tube constitute installation constraints which significantly lengthen the installation of the cable harnesses and which result in a risk of damage to the harness of cables. In addition, this installation requires the use of additional material (plugs, shrink tape, etc.), which further extends the installation time and makes it more complex.

STATEMENT OF THE INVENTION

In order to remedy the disadvantages of the state of the art exposed above, the main objective of the invention is to enable simplified, rapid and safe assembly of wiring ramps as well as to minimize tensions in the cable harnesses.

To do this, the invention plans to produce a ramp support positioned at the end of the ramp as mentioned above, while doing away with a heat-shrinkable protective end piece by integrating a cap into the support .

More precisely, the present invention relates to a support for holding at least one ramp of a wiring harness, this support being integral with a fixing bracket. The support comprises at least two sails per ramp, each sail being a support presenting a support surface for the wiring harness. These sails are separated by a hooping space and connected to the stem by a fixing base.

The holding support is a support positioned at the end of the ramp and called a “plug support” in which one of the sails, called the outer sail, has a non-through bore which has a bottom forming a plug and the other sails, called internal sails, have a through hole.

A ramp can then fit into the internal and external sails until it is positioned abutting against the bottom of the external sail.

The sails form parallel walls which extend from the fixing base. These sails constitute the body of the support support, providing it with a rigid structure into which the ramps fit. The sails also have a free end which provides a support surface for the wiring harness.

Advantageously, this plug-support according to the invention protects the wiring harness from direct friction on the ends of the ramps which are generally made up of hollow metal tubes. By covering the end of the ramps, the cap support provides protection to the ramp against corrosion by preventing the entry of corrosive substances into the ramps. In addition, this plug support eliminates the need for heat-shrinkable end caps conventionally installed at the end of the boom, thus reducing costs, installation time and the weight of the boom holding system.

Also advantageously, the insertion of the ramps into the support is carried out without tools and the hooping space is easily accessible, making it possible to respectively accelerate the rate of installation of the ramps and assembly of the harnesses. Indeed, if the hoop knot is positioned between the sail bearing surfaces, the wiring harness experiences a discontinuity between the sail bearing surfaces and is locally deformed, this deformation leading to damage to the harness. Accessibility to the hooping space therefore makes it possible to visually and quickly identify the configuration of the hooping nodes to modify them if necessary and speed up the assembly of the harnesses.

Also advantageously, the cap support is adaptable to current installations which include metal type jibs. A retrofit of the installations electrical aircraft is therefore possible to benefit from the benefits of the present invention.

According to preferred embodiments taken alone or in combination:

- the support comprises an external veil and an internal veil;

- the sail support surfaces are of circular section;

- the support is molded from plastic;

- the supporting surfaces have chamfered end edges;

- the internal sail has at least one circumferential groove in the through hole;

- the external sail has at least one circumferential groove in the non-through bore;

- the circumferential groove houses an O-ring seal;

- the external veil includes a buffer seal;

- the non-through bore of the external veil has a central sealing stud.

- the internal wall has a through adjustment slot between the through hole and the bearing surface of the internal wall allowing axial insertion of the ramp;

- the inner web and the outer web include a passage opening between the through hole and the support surface allowing radial insertion of the ramp and retention of said ramp by a clip effect;

- the passage opening has ramp retention fins;

- the external veil includes a device for inspecting the positioning of the ramp;

- the outer wall has a drainage hole in the non-through bore;

- the support is molded from plastic material having a non-abrasive surface finish, and

- the support and the stem are molded in one piece from plastic material.

Advantageously, the circular section of the support surfaces provides an adaptation of the support surfaces to the cylindrical shape of the harnesses with a diameter of between 5mm and 80mm which, in contact with the support surfaces, are therefore not crushed against these surfaces. 'support. This better distribution of stresses on the bearing surfaces reduces the level of stresses in the harnesses, thus increasing their lifespan. Also advantageously, the seals installed in the circumferential grooves make it possible to adapt the support to ramps of smaller diameters. When several successive circumferential grooves are molded into the sails, they also make it possible to seal the ramps without requiring joints.

Also advantageously, the plug supports according to the invention are adaptable depending on the type of installation: if the plug supports are installed first, the variant comprising a passage opening in the internal web is preferred because it allows rapid radial insertion ramps. If an axial installation of the ramps is preferred, the plug support variant with slots is then well suited.

Also advantageously, the inspection device makes it possible to check that the ramp is properly fitted and that the sealing is compliant.

Also advantageously, this stem equipped with supports makes it possible to optimally adapt to the number and position of the ramps and wiring harnesses.

The object of the invention also relates to a method of installing wiring harnesses on an avionics bay, these harnesses being routed by ramps held by holding supports as defined above. The installation takes place according to the following steps:

- assembly of ramp holding structure tools comprising holding supports;

- assembly of the wiring harnesses on the ramps by hooping;

- transfer of the assembly consisting of tools, ramps, retaining supports and wiring harnesses to the avionics bay;

- connection of the harnesses to the avionics bay, and

- removal of tools.

Advantageously, the tools have easy access to all the harnesses, ramps and support supports. Installing the harnesses on the support supports is therefore easier and quicker to implement. Also advantageously, the complete installation of the cabling is carried out on the tooling, the latter being placed on a bench, before being transferred directly to the avionics bay bringing simplicity and time saving to the installation.

According to certain preferred forms of implementation, taken alone or in combination:

- the tool assembly stage includes the assembly of a fixed structure and a mobile structure;

- a step of removing the mobile structure after the transfer step, and

- a stage of testing the harnesses after their assembly on the tools and before transfer to the avionics bay.

Advantageously, this testing step makes it possible to check the quality of the connections before installation on the avionics bay. These tests identify in particular assembly errors which can be corrected directly on the tooling which has easy access. This results in an improvement in the productivity of tasks relating to the installation of wiring harnesses.

PRESENTATION OF FIGURES

Other characteristics and advantages of the present invention will emerge on reading the following example of a detailed embodiment without limiting its scope, with reference to the appended figures which represent, respectively:

- Figure 1, a perspective view of two holding supports according to the invention carrying two ramps and two wiring harnesses;

- Figure 2, an exploded perspective view of the two holding supports and the two ramps;

- Figure 3, a sectional view along the ramps of the two holding supports according to Figure 1;

- Figure 4, a perspective view of one of the holding supports;

- Figure 5, a front view of this holding support; - Figure 6, a sectional view of the holding support;

- Figure 7, a sectional diagram of the holding support;

- Figure 8, a sectional diagram of the holding support with sealing grooves;

- Figure 9, a sectional diagram of the holding support with two O-rings;

- Figure 10, a sectional diagram of the holding support with a buffer seal;

- Figure 11, a sectional diagram of the holding support with a central stud;

- Figure 12 and Figure 13, a front and sectional diagram respectively of the holding support with a passage opening for radial insertion of a ramp;

- Figure 14, a sectional diagram of the holding support with a positioning verification hole;

- Figure 15, a diagram of the tooling before transfer to an avionics bay, and

- Figure 16, a diagram of the tooling after transfer to an avionics bay.

DETAILED DESCRIPTION

In the figures, identical reference signs refer to the same element as well as to the corresponding passages of the description.

Figure 1 and Figure 2 respectively show an assembled and exploded perspective view of four holding supports 1 according to the invention at the end of two ramps 6 - respectively two supports per ramp - each of the ramps 6 supporting a secure wiring harness 7 by a hoop 1c (2 hoops are shown in Figure 1). In this exemplary embodiment, the holding supports 1 are molded in plastic material two by two with a bracket 5 in one piece, this bracket 5 making it possible to hang the holding supports 1 on a bay aircraft avionics 9 (shown in Figure 16), the chosen plastic material having a non-abrasive surface state. Alternatively, the stem 5 and the holding supports 1 can be manufactured separately then joined together by any known fixing means (screw/nut, glue, clips) during installation.

Figure 3 represents a sectional view along one of the ramps 6 of the holding supports 1 of Figure 1. The ramp 6 is inserted at each of its ends 6a in a holding support 1 which comprises two sails, these sails being separated by a hooping space 1a and connected to the bracket by a fixing base 1b. The holding support 1 creates a plug in one of the sails, called the outer sail 2, from a non-through bore 2a of this external sail 2, the bottom 2d of which forms the plug, while the other sail, called the internal sail 3, has a through hole 3a. The ramp 6 therefore completely crosses the internal wall 3 and fits into the external wall 2.

The perspective view in Figure 4 illustrates the arrangement of the internal 3 and external 2 sails. Each sail has a support surface 3c, 2c on the wiring harness. This bearing surface 3c, 2c, of circular section, is adapted to the cylindrical shape of the wiring harnesses 7 with a diameter of between 5 mm and 80 mm which are therefore not crushed against these bearing surfaces 3c, 2c by the fretting. This hooping is carried out by inserting the hoop 1c (shown in Figure 1) or a tightening link in the hooping space 1a between the internal 3 and external 2 sails, this hoop wrapping around the ramp 6 and the wiring harness 7. In addition, the edges of the bearing surfaces 3c, 2c can be chamfered and thus limit damage by friction of the wiring harnesses 7 on the edges of these bearing surfaces 3c, 2c.

The internal web 3 also includes a through 3d adjustment slot between the through drilling 3a of the internal web 3 and the bearing surface 3c of this internal web 3. This 3d adjustment slot provides play to the through drilling 3a of the web internal 3 which facilitates the axial fitting of the ramp into the holding support. The sails also feature 3rd cells which optimize the mass and rigidity of the sails.

Figure 5 and Figure 6 respectively show a view of the holding support

1 from the front in alignment with the ramps 6 and a sectional view along plan A of the Figure 5. The through bore 3a and the non-through bore 2a each have a chamfer 3b, 2b in the insertion zone of the ramp 6, this chamfer facilitating the insertion of the ramp 6 into the holding support 1.

The diagram in Figure 7 shows a simplified view in plane A of Figure 5 of the sails of the holding support 1 and the end 6a of a fitted ramp 6. The 3d adjustment slot is shown in hatching. In the standard configuration, ramp 6 is a hollow metal cylinder. The through drilling and the non-through bore are adapted so that the metal cylinder is fitted by interference, thus providing the ramp with the desired tightness.

However, interference mounting involves very low manufacturing tolerances which often proves costly. To reduce these costs, the diagrams from Figure 8 to Figure 11 illustrate optional features aimed at improving the sealing of the retaining support while increasing manufacturing tolerances.

In the variant illustrated in Figure 8, the external veil 2 has three circumferential grooves 4a which facilitate the insertion by interference of the ramp 6 by providing flexibility to the non-through bore 2a, the seal being preserved.

In the variant according to Figure 9, the inner web 3 and the outer web 2 each comprise a circumferential groove 4a in, respectively, the through bore 3a and the non-through bore 2a, these circumferential grooves 4a being of greater dimension than those of Figure 8 to each house an O-ring seal 4b. Alternatively, only one of the internal 3 or external 2 sails has a circumferential groove 4a with an O-ring seal 4b. In addition to improving the sealing of the holding support and preventing particles or external fluids from entering the ramp 6 and the holding support 1, the O-ring seals 4b make it possible to adapt the holding support. maintaining 1 to ramps 6 whose diameter is less than that of the non-through bore 2a and the through bore 3a while maintaining the desired seal.

Alternatively to the O-ring seal 4b, the outer web 2 includes a buffer seal 4c as illustrated in Figure 10. This buffer seal 4c is inserted at the bottom 2d of the non-through bore 2a, the ramp 6 coming to rest on the buffer seal 4c once fitted. Alternatively also, the bottom 2d of the non-through bore 2a of the external veil 2 comprises a central sealing stud 2e which is inserted into the hollow of the ramp 6 as shown in figure 11. The ramp 6 is then embedded in the external veil 2, the support then being reinforced.

The variants presented in Figure 8 to Figure 11 can be combined with each other to adapt to the configurations of the ramp and the holding support.

Figure 12 and Figure 13 show a variant of the holding support in which the inner web 3 and the outer web 2 have an opening 3f between the through hole 3a and the bearing surface 3c, the opening 3f being wider than the adjustment slot 3d of Figure 4. This opening 3f is calculated to allow radial insertion “by force” of the clip type of the ramp 6 and retention thereof by clip effect. To improve this effect, the passage opening 3f comprises fins 3g for retaining the ramp 6, these fins 3g blocking the extraction of the ramp 6. This opening 3f also allows axial fitting of the ramp 6 into the support of maintenance 1.

Advantageously, the holding support 1 also includes a device for inspecting the positioning of the ramp 6 which makes it possible to verify that the ramp 6 is correctly fitted into the holding support 1 and in particular into the outer web 2. Figure 14 shows a viewing hole 4d passing through from the support surface 2c to the non-through bore 2a of the external web 2, this viewing hole 4d being located near the bottom 2d of the non-through bore 2a and making it possible to see the position of the ramp 6. To facilitate visualization, the ramp 6 is colored on a strip which, when the ramp 6 is well positioned, coincides with the viewing hole 4d. Alternatively, any device indicating positioning such as push button based mechanisms is usable as a positioning inspection device.

Figure 14 also shows a drainage hole 4e in the bottom 2d of the non-through bore 2a of the external veil 2. This drainage hole 4e evacuates the fluids which are accidentally trapped inside the ramp 6. In this example embodiment, the drainage hole 4e is drilled in the axis of the ramp 6. Alternatively and depending on the orientation of the holding support 1, the hole of drainage 4e can either be drilled in the bottom 2d of the non-through bore 2a and in any direction allowing optimized evacuation of fluids, or drilled in the non-through bore 2a directly. In particular, for a holding support 1 equipped with a viewing hole 4d and an O-ring seal 4b adapting the diameter of the ramp 6 to that of the non-through bore 2a, the viewing hole 4d makes also serves as a drainage hole.

The holding supports objects of the present invention are used in the installation of wiring harnesses 7 on an avionics bay 9 (shown in Figure 16), these wiring harnesses 7 being routed by ramps 6 held by the holding supports 1 . The installation takes place according to the following steps:

- assembly of ramp holding structure tools 6 comprising holding supports 1;

- mounting of the wiring harnesses 7 on the ramps 6 by shrink fit;

- transfer of the assembly composed of the tools, the ramps 6, the holding supports 1, and the wiring harnesses 7 to the avionics bay 9,

- connection of wiring harnesses 7 to avionics bay 9, and

- removal of tools.

Figure 15 shows the holding structure tooling, this comprising a fixed structure 8a and a mobile structure 8b to which the holding supports are attached. These fixed 8a and mobile 8b structures of the tooling are adapted to the geometry and arrangement of the equipment of the avionics bay 9. The fixed structure 8a creates a template to dimension the length of the connection ends 9b of the wiring harnesses 7. During the step of transferring the tooling to the avionics bay 9, only the mobile structure 8b is attached to the avionics bay 9 to transfer the holding supports 1 there. The mobile structure 8b is therefore removed after the step of transfer, as illustrated in Figure 16. Wiring harnesses 7 are installed on the ramps 6 by hooping (the hooping nodes are not shown).

With reference to Figure 16, the mobile structure 8b has been removed and the holding supports 1 are attached to the avionics bay 9 after transfer. The avionics bay has a structure of compartmentalized shelves in which the equipment 9a is installed. The equipment 9a is also connected to the wiring harnesses 7 either directly or via the connection ends 9c. This installation process advantageously includes a step of testing the harnesses after their assembly on the tooling and before transfer to the avionics bay. This step makes it possible in particular to check the quality of the connections and to identify assembly errors in order to correct them directly before transfer.

Claims

1. Holding support (1) for at least one ramp (6) of a wiring harness (7), this holding support (1) comprising at least two sails per ramp, each sail having a support surface (2c, 3c) to the wiring harness (7), these sails being separated by a hooping space (1a) and at least one sail, called internal sail (3), comprises at least one through hole (3a) characterized in that that the holding support (1) is integral with a fixing bracket (5), in that the sails are connected are connected to this bracket (5) by a fixing base and in that another sails, said external sail (2), comprises at least one non-through bore (2a) which each has a bottom (2d) forming a plug.

2. Holding support (1) according to the preceding claim, wherein the holding support (1) comprises an external veil (2) and an internal veil (3).

3. Holding support (1) according to any one of claim 1 to claim 2 in which the bearing surfaces (2c, 3c) of the sails are of circular section.

4. Holding support (1) according to any one of claim 1 to claim 3 wherein the holding support (1) is molded from plastic material.

5. Holding support (1) according to any one of claim 2 to claim 4 in which the internal web (3) comprises at least one circumferential groove (4a) in the through hole (3a).

6. Holding support (1) according to any one of claim 1 to claim 5 wherein the external web (2) comprises at least one circumferential groove (4a) in the non-through bore (2a).

7. Holding support (1) according to any one of claim 5 to claim 6 in which the circumferential groove (4a) houses an O-ring seal (4b).

8. Holding support (1) according to any one of claim 1 to claim 7 wherein the external veil (2) comprises a buffer seal (4c).

9. Holding support (1) according to any one of claim 1 to claim 7 in which the non-through bore (2a) of the external web (2) comprises a central sealing stud (2e).

10. Holding support (1) according to any one of claim 2 to claim 9 in which the internal web (3) comprises a through adjustment slot (3d) between the through bore (3a) and the surface d support (3c) of the internal veil (3).

11. Holding support (1) according to any one of claim 1 to claim 9 in which the internal web(s) (3) and the external web (2) comprise an opening (3f) for radial insertion by clipping of the ramp (6) between the through hole (3a) and the bearing surface (3c) of the internal wall (3).

12. Retaining support (1) according to claim 11 in which the radial insertion opening (3f) comprises retention fins (3g) of the ramp (6).

13. Holding support (1) according to any one of claim 1 to claim 12 in which the external veil (2) comprises a device for inspecting the positioning of the ramp.

14. Holding support (1) according to any one of claim 1 to claim 13 in which the external web (2a) comprises a drainage hole (4e) in the non-through bore (2a).

15. Holding support (1) according to any one of claim 1 to claim 14 in combination with claim 4 wherein the holding support (1) is molded in a plastic material having a non-abrasive surface condition.

16. Holding support (1) according to any one of claim 1 to claim 15 in which the holding support (1) and the bracket (5) are molded in one piece from plastic material.

17. Method for installing wiring harnesses (7) on an avionics bay (9), these wiring harnesses (7) being routed by ramps (6) held by holding supports (1) according to claim 1 to claim 16 characterized in that it comprises the following steps:

- assembly of ramp holding structure tools (6) comprising holding supports (1);

- mounting of the wiring harnesses (7) on the ramps (6) by shrink fit; - transfer of the assembly consisting of tools, ramps (6), holding supports (1) and wiring harnesses (7) to the avionics bay (9);

- connection of the wiring harnesses (7) to the avionics bay (9), and

- removal of tools.

18. Installation method according to claim 17 in which the step of mounting the tooling comprises the mounting of a fixed structure (8a) and a mobile structure (8b).

19. Installation method according to claim 18 in which a step of removing the mobile structure (8b) is carried out after the transfer step.

20. Installation method according to any one of claim 17 to claim 19 in which a step of testing the wiring harnesses (7) is carried out after their assembly on the tooling and before the transfer step.