Stress-relieving rear fitting for an electrical connector

Abstract

The invention relates to a rear fitting (15) for a harness (11) that is intended to be mechanically connected to a connector (10) and comprises: a fixed body (23) comprising a front end (23.1) and a rear end (23.2), a rotary nut (24) rotatably mounted on the front end of the fixed body (23), said rotary nut (24) being intended to provide a removable mechanical connection between said rear fitting (15) and the connector (10), and a movable body (27) comprising a front end (27.1) and a rear end (27.2), the front end (27.1) of the movable body (27) being mounted rotatably with respect to the rear end (23.2) of the fixed body (23), the rear end (27.2) of the movable body (27) comprising, at the outer periphery, a connection area (28) for connecting with a screen or sheath (17) for electrical protection and / or mechanical protection.

Description

DESCRIPTION TITLE: REAR STRESS-RELEASE FITTING FOR AN ELECTRICAL CONNECTOR

[0001] The present invention relates to a rear stress-relieving connector for an electrical connector. The invention finds application in the field of transport (land, aeronautical, space, nautical), construction (Buildings and public works - BTP), or medical for the transmission of electrical power between two electrical devices.

[0002] As is known per se, the function of transmitting electrical power between electrical equipment is provided by electrical harnesses. An electrical harness comprises at least one electrical cable that may contain one or more electrical conductors as well as connectors arranged at the ends of the cable(s) to establish electrical connections with one or more electrical equipment. Several branches may make up a harness. The harness may optionally include an electrical and / or mechanical protective sheath that may take the form of a textile or metal braid. The harness is said to be "shielded" when the sheath is conductive and provides protection against electromagnetic interference (called EMI protection), as is the case, for example, with a metal braid.

[0003] Figure 1 shows a connection between a movable part, called a plug, 10 of an electrical connector of a harness 11 and a fixed part called a base 12 of an electrical connector and associated with electrical equipment 13. In this case, the plug 10 is screwed onto the base 12. In the remainder of the document, the term "connector" refers indifferently to the fixed part, i.e. the plug, or the movable part, i.e. the base. The body of the base 12 is electrically connected to a structure of the electrical equipment 13 constituting an electrical ground. The plug 10 comprises electrical contacts intended to cooperate with electrical contacts of complementary shape of the base 12. A rear connector 15 is screwed onto the plug 10 by means of a screw ring 16.

[0004] An electrical protective sheath 17 in the form of a shielding braid is electrically connected to the rear connection 15 in a connection area in order to ensure optimal operation of the electrical systems with respect to lightning, electric arcs, partial discharges or even electromagnetic compatibility. For this purpose, a clamp 18 tightens the shielding braid 17 on a connection area of ​​the rear connection 15.

[0005] In order not to reverse functions on electrical equipment or the redundancy of electrical systems, a plug 10 and a corresponding socket 12 are coupled via a keying system 21, as shown in Figure 2.

[0006] This keying system 21 comprises a reference lug 22.1 corresponding to the angular reference of the connector composed of a plug 10 and a base 12. This reference lug 22.1 is used as an orientation reference for the connector. For this, it is positioned in a chosen direction. Additional lugs 22.2, 22.3, 22.4, 22.5 are arranged, for example, at predefined angles, A, B, C, D in the example of Figure 2, to form a keying key. The same connector will be available with different keying keys (additional lugs at different angles) to avoid interchanging the connections of several harness ends arriving at the same equipment. This keying system is used on most circular connectors in the transport sector, whether they are of European (BNAE, EN, or others) or American (MIL, SAE) standardization.

[0007] If the different lugs of the base 12 and the plug 10 are not arranged face to face with respect to each other, it is impossible to connect the two elements 10, 12 together.

[0008] For applications in which harnesses 11 are made of small cables having a diameter of a few millimeters, the harnesses 11 are considered "flexible". As illustrated in Figures 3a and 3b, these harness 11 allows a twist allowing the plug 10 to pivot according to the arrow F1 and to align to match the keying of the plug 10 and the base 12. It is then possible to establish the connection between the plug 10 and the base 12 according to the arrow F2.

[0009] However, to meet the increased need for electrical power inside new generation aircraft, the harnesses 11 comprise large diameter single-wire cables, which can be assembled to form multi-wires of several conductors, and which are covered by a shielding braid 17. The diameter of the single-wire cables is preferably between 5 and 25 mm and even more preferably between 8 and 20 mm.

[0010] This type of harness 11 is very rigid, which makes it difficult to connect it to electrical equipment. Indeed, during installation on an aircraft, one end of the harness 11 equipped with a plug 10 is connected to a first piece of electrical equipment. The harness 11 is then unwound and fixed by clamps to the structure of the aircraft. The opposite end must then be able to be connected to a second piece of electrical equipment. This operation can cause significant torsional stresses on the end of the harness 11, in particular to align the keying lugs of the plug 10 and the base 12. Handling can also damage and / or deform the shielding braid 17 by creating irregular openings at the level of the layers of strands, which greatly reduces the electromagnetic protection performance.

[0011] In addition, there are single-way plugs or sockets for single-wire cables, which rotate freely around the cable, which increases the possibility of deformation of the braid.

[0012] The problem described is not limited to the plug side, it is similar on the socket side when the connector is used to connect two harnesses together. In this case, the socket is also equipped with a rear connection and a shielding braid. The problem arises when fixing the socket to its support. The socket, generally with a square flange and four screws holding, must be positioned in a defined orientation, which may require twisting of the end. The invention therefore also applies to a base.

[0013] In other words, the installation of cabling is subject to numerous rules and dimensional constraints, and the low tolerances for setting and adjusting cable orientations and lengths offer little latitude to the operator, which can lead to the impossibility of installing the cabling, and generate numerous rejects and logistical disruptions.

[0014] Indeed, high-voltage harnesses provide much more rigidity than current flexible harnesses, and following their installation depending on the operators, this can generate very restrictive adjustments to the orientation of the rear connections.

[0015] As a result of these alterations, the electrical resistance values ​​are no longer guaranteed, which poses a risk to product conformity. Additional removal and measurement operations are then required, which are costly and time-consuming to perform.

[0016] In order to solve these problems, it is possible to connect the shielding braid 17 to the rear connector 15 when installing the harness 11, after connecting it to the electrical equipment 13. However, this requires an operator to make a braid connection for each aircraft, which generates additional costs and great complexity of implementation and presents risks of defects. This solution is therefore not feasible in the context of industrial mass production. In addition, quality controls on the products cannot be traced in production in the factories.

[0017] Another solution is to manufacture the harness 11 in 3D in the factory so that it has a morphology identical to its final installation. This induces a significant additional manufacturing cost for the realization of this complex operation which involves specific tools and requires having a 3D model of the installation on the aircraft which is not always available.

[0018] The invention aims to effectively remedy the aforementioned drawbacks by proposing a rear harness connector intended to be mechanically linked to a connector comprising: - a fixed body having a front end and a rear end, - a rotating nut rotatably mounted on the front end of the fixed body, said rotating nut being intended to provide a removable mechanical connection between said rear fitting and the connector, and - a mobile body comprising a front end and a rear end, the front end of the mobile body being rotatably mounted relative to the rear end of the fixed body, the rear end of the mobile body comprising on its external periphery a connection zone with an electrical protection and / or mechanical protection sheath.

[0019] The invention thus makes it possible, thanks to the movable body of the rear connector, to angularly reorient the plug of a harness relative to a base connector associated with electrical equipment by reducing the torsional stresses applied to the electrical and / or mechanical protective sheath to avoid any risk of degradation of said sheath in the rear area of ​​the connector. The invention also has the advantage of not requiring any modification of the orientation of the harness on the aircraft as well as having a low impact on the mass of the entire harness and a limited implementation cost.

[0020] According to one embodiment of the invention, the front end of the fixed body comprises a plurality of teeth arranged along its circumference intended to cooperate with teeth of complementary shape arranged on the connector.

[0021] According to one embodiment of the invention, a sealing O-ring is interposed radially between the front end of the fixed body and an internal face of the rotating nut.

[0022] According to one embodiment of the invention, at least one locking element is arranged radially between a periphery of the fixed body and a periphery of the mobile body, so as to link the mobile body in translation relative to the fixed body while allowing rotation of the mobile body relative to the fixed body.

[0023] According to one embodiment of the invention, the locking element is an elastic ring.

[0024] According to one embodiment of the invention, a sealing O-ring is interposed radially between a periphery of the fixed body and a periphery of the movable body.

[0025] According to one embodiment of the invention, said rear connection comprises an electrical continuity joint arranged radially between a periphery of the fixed body and a periphery of the mobile body.

[0026] According to one embodiment of the invention, the annular locking element is arranged axially between the sealing O-ring and the electrical continuity seal.

[0027] According to one embodiment of the invention, the movable body comprises a shoulder or a groove for fixing a heat-shrinkable sheath end piece.

[0028] According to one embodiment of the invention, said rear connection comprises a device for locking the movable body in rotation relative to the fixed body.

[0029] According to one embodiment of the invention, the fixed body, the rotating nut, and the movable body are made of an electrically conductive material, in particular a metallic material or a plastic material comprising a conductive coating.

[0030] The invention also relates to an assembly comprising a connector and a rear connection as previously defined, said rear connection being screwed onto said connector.

[0031] The present invention will be better understood and other characteristics and advantages will become apparent upon reading the detailed description which follows, comprising embodiments given for illustrative purposes with reference to the appended figures, presented as non-limiting examples, which may serve to complete the understanding of the present invention and the description of its implementation and, where appropriate, contribute to its definition, on which:

[0032] [Fig. 1] Figure 1, already described, is a side view illustrating a connection between a plug of a harness according to the state of the art with a base of electrical equipment;

[0033] [Fig. 2] Figure 2, already described, is a front view illustrating a keying system on a state-of-the-art electrical connector;

[0034] [Fig. 3a] [Fig. 3b] Figures 3a and 3b, already described, are schematic representations illustrating the connection of a plug associated with a flexible harness on a base;

[0035] [Fig. 4] Figure 4 is a side view of a rear connector of an electrical connector according to the present invention;

[0036] [Fig. 5] Figure 5 is a longitudinal sectional view of a rear connector according to the invention;

[0037] [Fig. 6] Figure 6 is a perspective view of a portion of an electrical continuity joint intended to be interposed between the fixed body and the movable body of the rear connector according to the invention;

[0038] [Fig. 7] Figure 7 is a side view of an alternative embodiment of a rear connection of an electrical connector according to the invention provided with a nut for locking the movable body in rotation relative to the fixed body.

[0039] It should be noted that in the figures the structural and / or functional elements common to the different embodiments have the same references. Thus, unless otherwise stated, such elements have identical structural, dimensional and material properties.

[0040] In the remainder of the description, the relative terms of the type "front", "rear" are understood by reference to the positioning of the element relative to the connector when the rear fitting is mounted on the connector, an element "front" being arranged on the connector side while a "rear" element is arranged on the side opposite the connector.

[0041] Figures 4 and 5 show a rear connection 15 of axis X intended to be mechanically connected to a plug-type connector 10, or a base-type connector comprising a fixed body 23, a rotating nut 24 intended to ensure a removable mechanical connection between said rear connection 15 and the connector and a movable body 27 which is movable in rotation relative to the fixed body 23. The body 23 is said to be "fixed" insofar as the body 23 is fixed relative to the connector when the rear connection 15 is screwed onto the connector by means of the rotating nut 24.

[0042] More specifically, as shown in Figure 5, the fixed body 23 has a front end 23.1 and a rear end 23.2. The fixed body 23 has an annular shape with an axial orientation relative to the X axis. The fixed body 23 has an internal diameter greater than that of the cable around which the rear connector 15 is positioned. The fixed body 23 can rotate around a cable of the harness which can be a single cable, before its attachment to the plug 10.

[0043] The front end 23.1 of the fixed body 23 comprises a plurality of teeth 29 arranged along its circumference intended to cooperate with teeth (not shown) of complementary shape arranged on the plug 10. These teeth 29 are arranged along a crown of axis X. These teeth 29 extend in axial projection relative to a plane perpendicular to the axis X. This toothing makes it possible to mechanically lock in rotation the connection between the plug 10 and the fixed body 23. In addition, the contact between the teeth is used to ensure electrical continuity with the lowest possible resistance, which is necessary to ensure electromagnetic protection. In the case of high voltage wiring, the teeth must also withstand the current returns of the shields linked to the inductive coupling which can reach several hundred amperes.

[0044] The rotating nut 24 is rotatably mounted on the front end 23.1 of the fixed body 23. For this purpose, an annular locking element 25, such as an elastic ring, is arranged inside a groove 26 made partly in a internal periphery of the rotating nut 24 and partly in an external periphery of the fixed body 23. The mounting of the rotating nut 24 is carried out on a screw thread of the plug 10. The screw thread can be of the self-tightening type in order to resist vibrations.

[0045] Furthermore, in a variant, a sealing O-ring 32 is interposed radially between an external periphery of the front end 23.1 of the fixed body 23 and an internal periphery of the rotating nut 24. The sealing O-ring 32 is arranged inside a groove 33 made partly in the fixed body 23 and partly in the rotating nut 24.

[0046] The movable body 27 has a front end 27.1 and a rear end 27.2. The movable body 27 has an annular shape of axial orientation relative to the axis X. An internal diameter of the front end of the movable body 27 is substantially equal to the external diameter of the rear end of the fixed body 23.

[0047] The front end 27.1 of the mobile body 27 is rotatably mounted relative to the rear end 23.2 of the fixed body 23. The rear end 27.2 of the mobile body 27 comprises at its outer periphery a connection zone 28 with a sheath 17 for electrical protection and / or mechanical protection. The sheath 17 may, for example, take the form of a metal braid sized to provide the electromagnetic shielding function. The connection zone 28 is constituted by a section of the mobile body 27 around which the shielding braid is held by means of a clamp (not shown). Alternatively, the sheath 17 may be a mechanical protection braid, composed of metal, textile, plastic or composite strands. The mechanical protection braid may, for example, be made of a thermoplastic material of the polyetheretherketone type known as "peek".The sheath 17 may also be composed of several braids to jointly ensure the functions of electromagnetic protection and mechanical protection. In a variant, the sheath 17 may be of the corrugated or convoluted conduit type, or a rigid tube.

[0048] At least one locking element 36 is arranged radially between a periphery of the fixed body 23 and a periphery of the movable body 27, so as to link the movable body 27 in translation relative to the fixed body 23 while allowing a rotation of the movable body 27 relative to the fixed body 23. The locking element 36 is arranged inside a groove 37 made partly in the periphery of the fixed body 23 and partly in the periphery of the movable body 27. The fixed body 23 can be arranged inside the movable body 27 or conversely the movable body 27 can be placed inside the fixed body 23. In this case, the locking element 36 is arranged radially between the external periphery of the fixed body 23 and the internal periphery of the movable body 27. Alternatively, in the case of reversed mounting, the locking element 36 is arranged radially between the internal periphery of the fixed body 23 and the external periphery of the movable body 27.

[0049] The locking element 36 may be an elastic ring, in particular of the circlip type (trade name) of square, rectangular or cylindrical shape (ring), or any other device making it possible to block the fixed body 23 and the mobile body 27 in translation while allowing freedom of rotation.

[0050] A sealing O-ring 40 is interposed radially between a periphery of the fixed body 23 and a periphery of the movable body 27. The sealing O-ring 40 is arranged inside a groove 41 made partly in the fixed body 23 and partly in the movable body 27. In this case, the sealing O-ring 40 is interposed radially between the external periphery of the fixed body 23 and the internal periphery of the movable body 27. Alternatively, in the case of reversed mounting, the sealing O-ring 40 is interposed radially between the internal periphery of the fixed body 23 and the external periphery of the movable body 27.

[0051] An electrical continuity joint 44 is arranged radially between a periphery of the fixed body 23 and a periphery of the mobile body 27. The electrical continuity joint 44 ensures the electrical continuity connection between the mobile body 27 and the fixed body 23. Without this joint 44, the rear connection 15 is not viable and does not guarantee the EMC (electromagnetic compatibility) connection and the returns of currents to the equipment.

[0052] In this case, the electrical continuity joint 44 is interposed radially between the external periphery of the fixed body 23 and the internal periphery of the mobile body 27. Alternatively, in the case of reverse mounting, the continuity joint electric 44 is interposed radially between the internal periphery of the fixed body 23 and the external periphery of the mobile body 27.

[0053] As illustrated in Figure 6, the electrical continuity joint 44 may comprise a plurality of curved metal strips 45 arranged side by side in an annular shape. These metal strips 45 are intended to be crushed between the periphery of the fixed body 23 and the periphery of the mobile body 27 to guarantee electrical continuity with low electrical resistance between these two elements 23, 27. The electrical continuity joint 44 is sized according to a return of a shielding current during inductive couplings of the order of several hundred amperes.

[0054] In the example shown, the annular locking element 36 is arranged axially, relative to the axis X of the rear connection 15, between the sealing O-ring 40 and the electrical continuity seal 44. However, the relative axial positioning of these three elements 36, 40, 44 may vary from one application to another.

[0055] The movable body 27 may also comprise a shoulder 48 or alternatively a groove for fixing a tip of a heat-shrinkable sheath (not shown). The shoulder 48 extends in radial projection relative to an external periphery of the movable body 27. Alternatively, the groove 48 extends in a radial recess relative to an external periphery of the movable body 27. This heat-shrinkable sheath makes it possible to ensure sealing between the wiring and the rear connection 15.

[0056] Advantageously, the fixed body 23, the rotating nut 24, and the movable body 27 are made of an electrically conductive material, in particular a metallic material. These different elements 23, 24, 27 are preferably made of steel, in particular stainless steel, or aluminum which have the advantage of having good mechanical strength as well as electrical conductivity and thermal conductivity to evacuate calories. These elements can be covered with a coating, such as for example a thin layer of nickel, making it possible to further improve the electrical conductivity on the surface. Alternatively, the fixed body 23, the rotating nut 24, and the movable body 27 are made of a plastic material comprising a conductive coating, or a plastic material incorporating electrically conductive fillers. The components of the rear connector 15 can be produced by conventional machining (turning and milling), 3D printing, or molding in the case of the use of conductive fillers.

[0057] In certain applications, it may be desirable to block the rotation of the movable body 27 relative to the fixed body 23, in particular in the case of use of the electrical harness in vibratory zones.

[0058] For this purpose, it is possible to glue the mobile body 27 with the fixed body 23 after having connected the connector to the base of the equipment.

[0059] Alternatively, as can be seen in Figure 7, the rear connector 15 comprises a nut 46 for locking the movable body 27 in rotation relative to the fixed body 23. The nut 46 carried by the movable body 27 is intended to cooperate with a screw thread made on the fixed body 23. The screw thread can be self-tightening. Once the plug 10 is connected to the base 12 of the equipment, the nut 46 can be screwed onto the screw thread of the fixed body 23 in order to permanently fix the position of the rear connector 15 of the harness.

[0060] Any other locking device may be used to stop the rotation of the movable body 27 relative to the fixed body 23, such as, for example, a needle screw or a washer braking system.

[0061] Of course, the various features, variants and / or embodiments of the present invention may be combined with each other in various combinations to the extent that they are not incompatible or mutually exclusive.

[0062] Furthermore, the invention is not limited to the embodiments described above and provided solely by way of example. It encompasses various modifications, alternative forms and other variations that may be envisaged by those skilled in the art within the scope of the present invention and in particular all combinations of the different operating modes described above, which can be taken separately or in association.

Claims

CLAIMS 1. Rear connector (15) of harness (11) intended to be mechanically linked to a connector (10), characterized in that said rear connector (15) comprises: - a fixed body (23) comprising a front end (23.1) and a rear end (23.2), - a rotating nut (24) rotatably mounted on the front end of the fixed body (23), said rotating nut (24) being intended to provide a removable mechanical connection between said rear fitting (15) and the connector (10), and - a movable body (27) comprising a front end (27.1) and a rear end (27.2), the front end (27.1) of the movable body (27) being rotatably mounted relative to the rear end (23.2) of the fixed body (23), the rear end (27.2) of the movable body (27) comprising at its outer periphery a connection zone (28) with a sheath (17) for electrical protection and / or mechanical protection, and - an electrical continuity joint (44) arranged radially between a periphery of the fixed body (23) and a periphery of the mobile body (27).

2. Rear connection according to claim 1, characterized in that the front end (23.1) of the fixed body (23) comprises a plurality of teeth (29) arranged along its circumference intended to cooperate with teeth of complementary shape arranged on the connector (10).

3. Rear connection according to claim 1 or 2, characterized in that a sealing O-ring (32) is interposed radially between the front end (23.1) of the fixed body (23) and an internal face of the rotating nut (24).

4. Rear connection according to any one of claims 1 to 3, characterized in that at least one locking element (36) is arranged radially between a periphery of the fixed body (23) and a periphery of the movable body (27), so as to link in translation the movable body (27) relative to the fixed body (23) while allowing rotation of the movable body (27) relative to the fixed body (23).

5. Rear connection according to claim 4, characterized in that the locking element (36) is an elastic ring.

6. Rear connection according to any one of claims 1 to 5, characterized in that a sealing O-ring (40) is interposed radially between a periphery of the fixed body (23) and a periphery of the movable body (27).

7. Rear connection according to claim 6, characterized in that the annular locking element (36) is arranged axially between the sealing O-ring (40) and the electrical continuity seal (44).

8. Rear connector according to any one of claims 1 to 7, characterized in that the movable body (27) comprises a shoulder or a groove (48) for fixing a heat-shrinkable sheath end piece.

9. Rear connector according to any one of claims 1 to 8, characterized in that it comprises a device (46) for locking the movable body (27) in rotation relative to the fixed body (23).

10. Rear connection according to any one of claims 1 to 9, characterized in that the fixed body (23), the rotating nut (24), and the movable body (27) are made of an electrically conductive material, in particular a metallic material or a plastic material comprising a conductive coating.

11. Assembly comprising a connector (10) and a rear connection (15) defined according to any one of the preceding claims, said rear connection (15) being screwed onto said connector (10).

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