Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
  • H02G1/00—Methods or apparatus specially adapted for installing, maintaining, repairing or dismantling electric cables or lines
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
  • H01B13/012—Apparatus or processes specially adapted for manufacturing conductors or cables for manufacturing wire harnesses
  • H01B13/01263—Tying, wrapping, binding, lacing, strapping or sheathing harnesses
  • H01B13/01272—Harness tying apparatus
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
  • H02G3/00—Installations of electric cables or lines or protective tubing therefor in or on buildings, equivalent structures or vehicles
  • H02G3/30—Installations of cables or lines on walls, floors or ceilings

Definitions

• TITLE Process for hooping an electrical bundle using simple ribbon hoops.
• This application relates to the production of electrical harnesses.
• the invention relates more specifically to the production of frets for the assembly of an electrical harness.
• electrical harness is used to designate a set of electrical wires or cables assembled together. Such a bundle is sometimes also called an “electric strand”, whether the cables are twisted together to form a twist or they run parallel to each other.
• electrical harness is also used to designate a set of electrical harnesses installed in an aircraft or other machine.
• the cables are usually assembled together by bands or collars.
• Various hooping techniques are known, all of which have their advantages and disadvantages.
• knotted thread hooping technique is the most widespread.
• a flat band or a narrow ribbon is preferably used (rather than a round wire) so as not to risk shearing the cable casing.
• EP1569856B1 discloses another technique using fastening strips covered with mechanical attachment elements of the loops and hooks type (the loops are arranged on the first face of the strip and the hooks on the second face).
• a flexible material for example an adhesive, is also present on one of the faces of the strip in the form of scattered spots or lines.
• the hoops obtained have the disadvantage of being thick and of easily catching on the surrounding elements (other beams, structural elements of the aircraft, insulating blankets, etc.), which makes the installation of the beams in an aircraft (or other gear) more delicate.
• the bands used are expensive and, in the case where the flexible material is adhesive, its presence on one of the faces of the strips prevents them from being prepared upstream and from being packaged in the form of a very long reel.
• the rigidity of the strips proposed by EP1569856B1 limits their use to the assembly of large-diameter bundles.
• GB2528928 offers another type of link, comprising a body in the form of a band of constant width and a head of greater width.
• the head has two portions separated by a fold line: a first portion on the side of the body which is provided with a slot in which the free end of the body can be inserted, and an adhesive portion on the side affixed to the body, initially covered of a removable sheet.
• a first portion on the side of the body which is provided with a slot in which the free end of the body can be inserted
• an adhesive portion on the side affixed to the body, initially covered of a removable sheet.
• Aeronautical electrical harnesses are therefore essentially assembled with knotted bands, which have the advantage of not risking damage other systems and facilitate the installation of harnesses.
• Various techniques are known, such as simple hooping, characterized by independent hoops, or continuous hooping characterized by successive hoops formed without interruption of the wire, essentially reserved for straight or bypass zones.
• the hoops made in this way use a substantial length of tape and generate significant off-cuts, which also increase the manufacturing costs of the electrical harnesses.
• this stain causes major musculoskeletal disorders for operators.
• the invention aims to overcome at least one of the above-mentioned drawbacks, by providing a method of hooping an electrical bundle by ribbon hoops which is simpler, faster and more economical than the known methods, while guaranteeing the Obtaining solid and correctly tightened frets.
• Another object of the invention is to provide a method which can be automated.
• the invention proposes a method of hooping an electrical bundle by simple ribbon hoops, in which the production of a hoops includes ribbon lacing around the harness and tightening the lacing.
• the process is characterized in that:
• no stopper knot, tie knot or loop knot is made in the method according to the invention.
• the process can be automated, which not only results in a gain in productivity and the total elimination of musculoskeletal disorders among operators, but also a reduction in the quantity of hoop tape required and cutting scrap. .
• bonding the lacing to itself prevents the hoop from slipping along the beam by extending the bonding area by capillary action under the hoop.
• ribbon designates, within the framework of the invention, both a flat yarn and a round yarn or even a textile tape, for example a tape of woven synthetic fibers such as Nomex® fibers which have the advantage of very low combustibility and high stability at high temperature.
• the ribbon has a ribbon part wrapped around the beam and a free part.
• the first dot of glue is deposited on the part of ribbon wrapped around the bundle, and the free part of the ribbon is folded over the first dot of glue, causing the lacing to stop by sticking on himself.
• the lacing of the ribbon around the electrical harness consists of making a flowing link around the harness electric, and the lacing is glued to itself by the first point of glue at the level of the sliding link.
• the flowing link is carried out as follows.
• Ribbon lacing around the harness consists of forming a braid bounded by two strands with a piece of ribbon of predetermined length, by folding the piece of ribbon in half, winding the braided piece of ribbon around the electrical harness and inserting the two strands of the ribbon in the braid, the tightening of the lacing consisting in then pulling on the two strands.
• the first dot of glue is applied to the strands near the top of the loop, on the side of said top, that is to say on the portion of tape surrounding the bundle, then the lacing is tightened by pulling on the two strands, the first point of glue thus finding itself stuck between the strands and the top of the braid.
• the tightening causes pressure on the glue point which promotes bonding.
• the lacing is first tightened by pulling on the two strands, then the first point of glue is placed astride the top of the braid and the strands to achieve the stop by gluing the lacing.
• a second dot of glue is deposited on the lacing (that is to say on the portion of ribbon surrounding the bundle) at a distance from the top of the braid and the strands are folded over the second dot of glue, the second dot of glue thus maintaining the strands in the folded-down position.
• a fast-setting glue of less than or equal to 3s such as a cyanoacrylate glue
• the second dot of glue has the function of keeping the folded strands and the lacing tight (with the desired tension) while the first dot of glue polymerizes.
• an adhesive whose setting is considered too slow (because greater than 3s) in particular an adhesive resistant to high temperatures, for example greater than 85° C.
• the lacing of the ribbon around the electrical bundle may consist of making a link flowing around said bundle.
• the lacing of the tape may consist in wrapping the tape around the bundle, the tightening of the lacing preferably taking place as the wrapping progresses.
• the wrapping can be carried out in such a way as to make several turns around the electrical harness, for example two or three turns.
• the number of turns and the offset between two consecutive turns along the axis of the wiring harness can be determined according to the desired width for the hoop.
• two points of glue can be provided, namely a point of glue on the first turn to stop an upstream end of the lacing and a point of glue on the last turn to stop a downstream end of the lacing.
• the "first point of glue" previously defined corresponds to the downstream point of glue deposited on the last round of the wrapping.
• the upstream neck stitch deposited on the first wrap is optional, the upstream end of the tape can be clamped (and thus maintained) by the following wrapping wraps.
• a fast-setting crystalline glue is used (for the first point of glue).
• this glue is chosen from cyanoacrylate glues, photoactive glues.
• Crystalline glues and in particular cyanoacrylate glues, have the advantage of being durable; their structure is intact after 40 years and more, unlike some two-component adhesives which disintegrate over time.
• the hooping process comprises a final step of sectioning excess ribbon strands.
• This step may be optional, in particular if the process is automated.
• the lacing requires the use of a piece of pre-cut ribbon, it is easy to provide a length of ribbon corresponding to the length necessary for said lacing, possibly increased by a gripping section allowing the automaton to manipulate piece of tape; this gripping section can be reduced to the strict minimum, to about 10mm (much less than that necessary for human handling in the case of a non-automated process, and which is about 250mm); the gripping section can be left in fine on the shrunken electrical bundle so that no final step of sectioning excess strands is then provided, which further reduces the execution time (and the costs) of the method.
• Figure 1 illustrates a first step of a first embodiment of the shrinking process according to the invention on a beam seen in perspective;
• FIG.2 Figure 2 illustrates a second step of this first embodiment
• FIG.3 Figure 3 illustrates a third step of this first embodiment
• Figure 4 illustrates a fourth step of this first embodiment
• Figure 5 illustrates the fourth step of a second embodiment which includes steps 1 to 3 identical to the first embodiment.
• FIG. 1 represents an electrical harness 2, which comprises a plurality of wires twisted so as to form one or more strands 4 as well as a plurality of parallel cables 6.
• an electrical harness 2 which comprises a plurality of wires twisted so as to form one or more strands 4 as well as a plurality of parallel cables 6.
• this is in no way limiting, and the method according to the invention applies to all types of electrical bundles, in particular bundles comprising only parallel cables or wires or comprising, conversely, only twisted strands.
• a first dot (or bead or drop) of glue 14 is deposited on the two strands 12 (fig.3), near the top of the braid 10, on the side thereof (that is to say the side opposite the free ends of the strands 12), that is to say close to the top of the braid on the portion of ribbon which surrounds the bundle 2; for example, a fast-setting crystalline glue such as a cyanoacrylate-based glue is used;
• the sliding link is immediately tightened, before the glue sets, by pulling on the two strands 12 in the direction indicated by the arrow drawn in Figure 4.
• the first point of glue 14 approaches the top of the loop and finds itself wedged between the top of the loop and the strands (fig. 4). Tightening also helps to spread the glued area.
• the dot of glue secures the top of the braid 10 to the strands 12 and keeps the lacing closed and tight.
• the rapid setting of the glue ensures that the clamping force applied by pulling on the strands remains the same after the glue has polymerized when the strands are released.
• the ribbon 8 used according to the invention is a simple ribbon, for example a flat yarn or a strip of fabric, preferably of constant width, devoid of hook-and-loop type attachment surface and devoid of adhesive surfaces, which reduces the cost price compared to the tape of EP1569856 and the tie of GB2528928.
• the tape 8 is also more flexible and less bulky than that disclosed by EP1569856.
• Tape 8 can advantageously be cut from a reel of tape of great length, unlike the prior tape and tie mentioned above.
• the execution times and the costs generated by the method according to the invention are disproportionate to those of the methods of EP1569856 and GB2528928.
• the illustrated method allows a reduction in fret tape waste of 10cm per fret, i.e. a saving of 100km of tape for one million frets.
• the production of the hoop comprises lacing, tightening of the lacing and stopping by depositing at least one dot of glue (known as the first dot of glue) to the gluing of the lacing on itself, and this, without it being necessary to make a single self-locking knot.
• glue known as the first dot of glue
• the lacing of the tape around the bundle can be done differently, for example by wrapping.
• the method according to the invention may comprise the application of a second dot of glue as explained below with reference to Figure 5.
• Figure 5 illustrates the fourth step of a second embodiment of the invention in which the steps illustrated in Figures 1 to 3 are first carried out, in the same way as for the first embodiment.
• two dots of glue are deposited on the lacing, namely: the first dot of glue 14 which is deposited near the top of the loop 10 before tightening the lacing; and a second dot of glue 15 deposited at a distance from the top of the braid on the portion of tape which surrounds the bundle.
• This second point of glue can be deposited before or possibly after tightening the lacing.
• the free portion of the ribbon (free end of the strands 12) is then (after tightening) folded over the second point of glue15.
• the second dot of glue 15 keeps the strands 12 in the folded-down position and the lacing tight while the first dot of glue 14 polymerizes. This makes it possible to use, for the first point of glue, a glue whose setting is considered too slow because it is for example greater than 3s, for example a glue capable of withstanding high temperatures, in particular greater than 85° C, which is not the case with known cyanoacrylate adhesives.
• the glue used for the second point of glue 15 is, on the other hand, chosen from glues with rapid setting of less than 3s, such as cyanoacrylate glues. It does not matter that this second point of glue 15 is then, in use, weakened by the exposure of the bundle to a temperature above 85° C., the holding and tightening of the hoop remaining ensured by the first point of glue 14 .

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• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Package Frames And Binding Bands (AREA)
• Insulated Conductors (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=77519368

Family Applications (1)

Country Status (3)

Family Cites Families (4)

• 2021
  • 2021-07-26 FR FR2108101A patent/FR3125654B1/fr active Active
• 2022
  • 2022-07-25 EP EP22757548.7A patent/EP4378034A1/de active Pending
  • 2022-07-25 WO PCT/EP2022/070815 patent/WO2023006675A1/fr active Application Filing

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