ELECTRICAL CONNECTION ASSEMBLY WITH SHIELD CONTINUITY

Abstract

The invention relates to an electrical connection assembly comprising at least a first conductor (C1) and a second conductor (C2), each conductor comprising a core (3) and a shield (4), an electrical junction box (1) for establishing selective electrical coupling of the conductors two by two, an external screen (2) at least partially enveloping the electrical junction box, a plurality of metal clips (5), each ensuring electrical contact with the shield (4) of a conductor, each clip being electrically connected to the external screen by a flexible conductive bridge (6), characterized in that the external screen comprises an expandable sheath (20). Figure 1

Description

Title of the invention: ELECTRICAL CONNECTION ASSEMBLY WITH SHIELD CONTINUITY

[0001] The invention relates to an electrical connection assembly with continuous shielding. More specifically, the invention relates to an electrical connection assembly comprising at least one first conductor or a first pair of conductors and, respectively, a second conductor or a second pair of conductors, connected together by means of an electrical junction box, each conductor comprising a core and a shield. Particular interest is given to the so-called "high-voltage" electrical harness in an electric vehicle or in a hybrid vehicle.

[0002] We are talking here about electrical conductors with a substantial cross-section, typically more than 3 mm2 each, most often more than 5 mm2 each, each of which is capable of carrying significant electrical power in terms of current and / or high voltage.

[0003] The electrical junction box is configured to establish an electrical connection of the conductors in at least two pairs. The electrical junction box can form a T or Y connection.

[0004] However, conventional type electrical junction boxes used for the so-called "high voltage" electrical network in an electric or hybrid vehicle do not have shielding or shielding connection.

[0005] In the context described above, the inventors sought to propose a solution to ensure continuity of the shielding and, incidentally, improved performance with respect to electromagnetic interference received and emitted. Secondarily, they also sought to minimize the number of components required.

[0006] To this end, the present invention proposes an electrical connection assembly comprising: - at least one first conductor and one second conductor, each conductor comprising a core and shielding, - an electrical junction box, to establish a selective electrical connection of conductors in pairs, - an external screen at least partially enveloping the electrical junction box, - a plurality of metal clips each ensuring electrical contact with the shielding of a conductor, each clip being electrically connected to the external screen by a conductive bridge, characterized in that the external screen comprises a flexible and / or extensible envelope.

[0007] The term "extensible" used here to describe an envelope, which envelope is a thin element extending locally in two directions perpendicular to its thickness, means that the envelope is capable of undergoing substantial elongation in at least one of the directions perpendicular to its thickness. The rate of elongation can be at least 5%.

[0008] The qualifier "flexible" used here to describe an envelope, which envelope is a thin element extending locally in two directions perpendicular to its thickness, means that the envelope is capable of undergoing substantial bending by pivoting around at least one of the directions perpendicular to its thickness.

[0009] It should be noted that elongation and bending deformations can combine to result in three-dimensional deformations. Furthermore, either elongation or bending deformation can be used alone. Thanks to the provisions described above, the basic electrical connection is supplemented by protection obtained through continuous shielding connecting the various conductor shields and the external screen.

[0010] The protection conferred is on the one hand of the order of the electrical safety of individuals and on the other hand of the electromagnetic order.

[0011] In the simplest example, the junction box allows the first conductor to be connected to the second conductor, either directly, via a fuse, or via a fuse and a relay-type switching device. In more complex examples, some of which will be examined in detail later, the junction box may be designed to connect more than two conductors or even more than two pairs of conductors. It is therefore understood that the junction box may contain one or more fuses and one or more power relay-type switching devices.

[0012] It should be noted that the conductors can be multi-strand copper conductors or aluminum alloy conductors. In a typical application, for a bundle intended to carry substantial electrical power, each conductor has a conductive cross-section of at least 3 mm².

[0013] The extensibility and / or flexibility of the casing allows the proposed arrangement of the external screen with the metal clips to be used for several sizes and / or geometric configurations of the electrical junction box. This advantageously reduces the technical diversity.

[0014] In other words, thanks to the extensibility / flexibility of the casing, the proposed external screen can be used for different types of junction boxes having different geometric configurations.

[0015] It is noted that the bridges are flexible, and that the conductive bridges are of short length and do not require any special means of retention.

[0016] The term "external screen" should be interpreted here in a broad sense; this screen can take several possible forms: a generally prismatic case shape, a simplified case shape, a flexible sheath shape forming a sock, a protean wrapping shape, this list not being exhaustive.

[0017] According to one embodiment, the assembly comprises a first pair of conductors CPI which includes the first conductor Cl and a third conductor C3 and a second pair of conductors CP2 which includes the second conductor C2, and a fourth conductor C4.

[0018] The electrical junction box selectively connects Cl to C2, and C3 to C4. In practice, each pair (also called 'pair') of conductors comprises a positive line conductor and a negative line conductor.

[0019] Thanks to which, the connection assembly proposed here manages simultaneously in parallel the paths of a positive line and a negative line of a high voltage power supply.

[0020] In this case, there are four metal clips making contact with the conductor shielding.

[0021] According to one embodiment, the electrical junction box forms a load-bearing structure to support the external screen. The external screen benefits from the fixing and support of the electrical junction box.

[0022] It is noted that one or more passages may be provided in the external screen to give access to the fixing elements by screwing or otherwise of the junction box on a base.

[0023] According to one embodiment, the electrical junction box is made of plastic. It should also be noted that it is possible to have the electrical junction box made of a light metal alloy.

[0024] According to one embodiment, the external screen is formed as a flexible, wraparound case.

[0025] The term "flexible" used here to describe a case, which case is locally a thin element extending locally in two directions perpendicular to its thickness means that the case is capable of undergoing substantial bending by pivoting around at least one of the directions perpendicular to its thickness.

[0026] The case may include more rigid parts, or even hinged portions. The case wall may be extensible, in addition to its flexibility.

[0027] Thus this case can conform to the shape of the electrical junction box from the outside.

[0028] According to one embodiment, the external screen is formed as a two-part housing, These parts are designed to be assembled to form a wraparound screen-case. A hinge between the two parts is possible. Assembly using an elastic band is also possible. There are no limitations on the two parts or their assembly configuration.

[0029] According to one embodiment, each conductive bridge is formed by a metal braid. Such a solution is robust and the braid facilitates welding both on the clamps and on the external screen.

[0030] The bridges can also be formed as standard flexible multi-strand wires.

[0031] According to one embodiment, the flexible and / or expandable casing is made of unwelded wire mesh. This wire mesh can be formed as a matrix of metal wires intertwined or braided together.

[0032] This is an elegant solution that is inherently conductive, expandable, and adaptable in dimensions. Optionally, semi-rigid reinforcements can be provided in association with the metal mesh; the reinforcements do not necessarily have to be metallic themselves, but provide a certain structure to the external screen.

[0033] Advantageously, the expandable envelope comprises a wall that is expandable in both dimensions perpendicular to its thickness.

[0034] According to one embodiment, a grounding clamp is also provided, configured to connect the external screen to an electrical ground of the electric vehicle.

[0035] According to one embodiment, the connection assembly may further include a third pair of conductors CP3 comprising a fifth conductor C5 and a sixth conductor C6.

[0036] The electrical junction box selectively connects Cl to C2 and C5 on the one hand, and C3 to C4 and C6 on the other hand.

[0037] Accordingly, the general electrical diagram of the proposed assembly can be in a T configuration or in a Y configuration, for example for a two-conductor power supply line, positive and negative.

[0038] In this case, the function of the junction box may be, for example, to switch between a direct current supply and an alternating current supply in an electric vehicle charging scheme.

[0039] The invention further relates to an electric or hybrid vehicle comprising at least one electrical connection assembly as described above.

[0040] The invention will be further detailed by describing non-limiting embodiments, and based on the accompanying figures illustrating variants of the invention, in which: [Fig.l] shows, in schematic top view, an electrical connection assembly according to the proposed configuration, allowing two pairs of electrical conductors to be connected; [Fig.2] schematically illustrates, in perspective view, a first example of the case format an external screen; [Fig.3] schematically illustrates in top view another set of another example of electrical connection; [Fig.4] schematically illustrates in perspective view, a second example of the external screen in the form of a case, the case being pre-arranged in a folded-over form on the junction box before assembly of the conductors; [Fig.5] is analogous to [Fig.4] and shows the second example of the external screen in the form of a case schematically after assembly of the conductors, the clips of the shielding function and the case deployed; [Fig.6] schematically shows, according to a view transverse to the conductors, another solution for forming the external screen with adaptable shape.

[0041] In the various figures, the same reference numerals designate identical or similar elements. For the sake of clarity, some elements are not necessarily shown to scale.

[0042] Figure [1] illustrates a first example of an electrical connection assembly according to the present invention.

[0043] The assembly comprises four conductors, namely a first conductor Cl, a second conductor C2, a third conductor C3 and a fourth conductor C4.

[0044] According to another point of view, the assembly comprises a first pair of conductors CPI which includes the first conductor Cl and the third conductor C3 and a second pair of conductors CP2 which includes the second conductor C2 and the fourth conductor C4.

[0045] Each conductor comprises a core 3 and a shield 4.

[0046] More specifically, the conductive core 3 is surrounded by a first insulating sheath marked 11, which is surrounded by the shielding layer 4, which is in turn surrounded by a second external insulating sheath marked 12.

[0047] The conductive core 3 is of the multi-strand copper type or an aluminum alloy core. Each conductor has a conductive cross-section of at least 3 mm². There is no limitation on the cross-section of the conductors here, but the most typical application of the invention concerns conductors with an electrical cross-section between 3 mm² and 10 mm².

[0048] In the figures, the elements are referenced in space with respect to an orthonormal frame comprising a vertical axis Z, a longitudinal axis X corresponding to the principal axis of the conductors, and a transverse axis Y perpendicular to the vertical axis and the longitudinal axis.

[0049] The assembly includes an electrical junction box 1, or simply called a junction box, designed to establish a selective electrical coupling of the conductors two by two.

[0050] As shown in [Fig. 1], the junction box 1 allows the first conductor Cl to be connected to the second conductor C2, either directly, or via a fuse, or via a fuse and a relay-type switching device (contactor). (insulation in the generic sense). Junction box 1 allows the third conductor C3 to be connected to the fourth conductor C4, either directly, or via a fuse or via a fuse and a switching device.

[0051] In the example illustrated in [Fig. 1], each conductor comprises one end fitted with a holed lug 8 crimped onto the core 3 and screw-coupled to a busbar 31. As known per se, the insulating sheaths and the shielding have been stripped to a sufficient length to allow crimping of the holed lug 8. Furthermore, the outer sheath has been stripped to a greater length to allow direct access to the shielding by a clamp 5 as will be described in more detail later.

[0052] Preferably, the shielding sheath is stripped so that the shielding does not penetrate inside the junction box 1.

[0053] It is therefore understood that the junction box 1 can contain one or more fuses and one or more switching elements of the power relay type, as schematically represented at reference 30 on [Fig.1].

[0054] The junction box 1 can be, for example, a switching box in an electric vehicle charging architecture which allows switching an alternative electrical energy source to one pair of vehicle conductors and a direct current energy source to another pair of vehicle conductors (for example, direct connection to the vehicle battery for fast charging).

[0055] The voltage that can prevail in the conductors can be a few hundred volts, knowing that the voltage at the terminals of the vehicle's main battery can range from 100 volts to more than 400 volts.

[0056] The electrical conductors involved here can support a current flow of several tens of amperes.

[0057] Advantageously according to the present invention, the assembly includes an external screen 2.

[0058] The function of this external screen is to allow an electrical connection between the different shields of the conductors involved in the junction box.

[0059] Furthermore, an auxiliary function of this external screen is to improve the electromagnetic behavior of the junction box, on the one hand with respect to incident radiative electromagnetic disturbances which can affect the proper functioning of the local electronics, and on the other hand to reduce its emissivity level when switched currents may pass through this junction box or also during the switching of the switching element arranged in the junction box (ON / OFF function).

[0060] In general, the external screen 2 at least partially encloses the electrical junction box 1. The external screen can totally enclose the junction box, as schematically shown in figures 1 and 2.

[0061] The external screen 2 is formed as a two-part housing, which can be assembled to form a wraparound screen housing. For example, it may consist of two half-shells that are assembled together to form an external screen housing. A hinge between the two half-shells may or may not be provided. The assembly may be held in place by an elastic band that encircles the two half-shells.

[0062] To make the expandable wall 20 of the external screen, a metal mesh or wire mesh, of reference 24, can be used, and an example of which is shown in [Fig.2] in the detail window.

[0063] This wire mesh 24 can be formed as a matrix of metal wires not welded together, interlaced or braided together. Due to the assembly structure in question, it exhibits a certain extensibility in directions perpendicular to the thickness of the mesh, and it exhibits flexural flexibility.

[0064] Depending on the need for self-supporting of the external screen, support reinforcements cooperating with the wire mesh (not shown in the figures) may be provided.

[0065] In addition, there are provided metal clips 5, each to ensure electrical contact with the shielding 4 of a conductor.

[0066] The number of metal clamps can be equal to the number of conductors arriving at the junction box.

[0067] According to one option, the assembly also includes a grounding clamp, marked 7, configured to connect the external screen to an electrical ground of the vehicle. According to this option, the number of metal clamps can therefore be equal to the number of conductors arriving at the junction box +1, so here seven clamps in total for three pairs of conductors.

[0068] Each clamp 5 is electrically connected to the external screen by a conductive bridge.

[0069] According to a relevant example, each bridge is flexible and each conductive flexible bridge is formed by a metal braid. It is not excluded to make the bridges from conventional wires.

[0070] In a particular example, the length of each bridge is between 10 mm and 25 mm. This avoids the need to hold the bridge, as holding it at both ends is sufficient.

[0071] A first end of the bridge 61 is connected by welding for example to the expandable envelope 20 and a second end of the bridge 62 is connected to a respective clamp 5.

[0072] Metal clips can take the form of: deformable clips, shrink rings, crimpable sleeves, spring clips, claw rings, etc.

[0073] The function of each metal clip 5 is to establish an electrical contact between the shielding sheath 4 and the bridge 6. The embodiment of the clip can be any shape to achieve the function in question.

[0074] According to one embodiment, each clamp 5 allows crimping of a shielding sheath having a diameter between 3 mm and 8 mm.

[0075] The function of the metal clamp 7 is to ground and ensure continuity between a ground point of the vehicle and the external screen 2.

[0076] According to a basic connection assembly shown in [Fig. 3], the external shield does not cover the conductor entry points into the junction box. The external shield can cover three or four faces parallel to the X-axis. Electrical continuity of the shielding is maintained, but the electromagnetic shielding function essentially protects the core of the junction box.

[0077] Figure 3 also shows a variant of electrical coupling between each conductor and the internal elements of the junction box; here a tongue and clip coupling is used, generally marked by 8' (this arrangement being assumed to be known, it is not described in detail here).

[0078] The electrical junction box 1 forms a load-bearing structure to support the external screen. The external screen 2 benefits from the attachment and support of the electrical junction box 1.

[0079] The junction box 1 is made of rigid plastic. However, it is not excluded that the junction box may be made of a light metal alloy.

[0080] As seen in [Fig.6], the junction box 1 may include a box body 15 and a cover 14. The cover may or may not be hinged on the box body.

[0081] The junction box may include one or more fixing tabs marked 19.

[0082] As illustrated in [Fig. 4] and 5, the external screen 2 can be formed as a case flexible wrap-around that conforms to the shape of the electrical junction box from the outside.

[0083] Before connecting the shield continuity clips, the flexible sheath can be mounted in a rolled-up, sock-like fashion around the middle part of the junction box as illustrated in [Fig.4].

[0084] It is noted that the junction box is fixed to a base by screws 9, only one of which is visible in figures 4 and 5.

[0085] We note that conductor C5 is parallel to conductor Cl and is located above conductor CL II. The same is true for conductor C6 arranged parallel to and above conductor C3.

[0086] In [Fig. 5], the clamps 5 have been installed on each of the conductors and the screen External 2 was deployed on both sides along the longitudinal direction X for cover the entire junction box as well as the areas where the conductors enter the junction box.

[0087] One or more packing collars 16 may be provided, which allows the opening in the conductor entry zone to be closed on each side and the position of the bridges 6 to be stabilized.

[0088] Figure 6 illustrates another variant in which a wire mesh encloses the junction box 1 with a cover area equipped with a retaining system 26, for example, a hook and loop system ('Velcro™'). The hook and loop system can be sewn onto the wire mesh.

[0089] The size of the external screen can thus be generally adjusted relative to the size of the junction box, in particular according to the cross-section in the YZ plane. This can complement the geometric adaptation along the longitudinal X direction discussed previously.

[0090] Accordingly, the external screen proposed here allows for extensibility along at least one dimension, preferably two '2D' dimensions, and even more preferably, along three '3D' dimensions to perfectly adapt to the geometry of the junction box 1

[0091] According to alternative embodiments, the flexible and / or stretchable outer screen cover 20 can be made of elastic composite material loaded with conductive fibers.

[0092] In an example illustrated in [Fig.2] and 4, the connection assembly further includes a third pair of conductors CP3 comprising a fifth conductor C5 and a sixth conductor C6. The junction box thus makes a T or Y connection.

[0093] It is noted that the fifth and sixth conductors can have an axis parallel to the first four conductors, i.e. along X, or in reference to [Fig.2], the fifth and sixth conductors can have an elongation axis perpendicular to the first four conductors, i.e. along the transverse direction Y.

[0094] In the illustrated examples, the second pair of conductors enters from the opposite side of the junction box to the first pair of conductors. It could be otherwise: all the conductors could enter from the same side of the junction box (dead-end box).

[0095] Other topological configurations are possible depending on the integration requirements of the junction box and the pairs / couples of high-voltage conductors in the vehicle architecture.

[0096] For example, as illustrated in [Fig. 6], the four conductors entering through the same face of the junction box (C1, C3, C5, C6) can be placed in a staggered pattern, which allows for optimization of the box size and the space occupied by the four wires in the harness near the connection assembly.

[0097] In a simplified example, the junction box could selectively connect the first conductor C1 with the second conductor C2 without any other additional conductor being involved. Optionally, there could be a third conductor C5. In this simplified example, all conductors are at the same potential, and there can be a first junction box for the high-voltage positive line and a second junction box for the high-voltage negative line.

[0098] It is noted that the shielding does not penetrate the housing and remains at a distance from the positive and negative poles.

[0099] It should be noted that the external screen 2 improves the electromagnetic behavior of the electrical junction box, on the one hand in susceptibility, i.e. resistance to incident disturbances that may occur on the junction box, and on the other hand in muteness, i.e. limiting the emissions of electromagnetic disturbances emitted by the junction box itself.

Claims

Demands

1. Electrical connection assembly comprising: - at least one first conductor (Cl) and a second conductor (C2), each conductor comprising a core (3) and a shield (4), - an electrical junction box (1), for establishing a selective electrical coupling of the conductors two by two, - an external screen (2) at least partially enveloping the electrical junction box, - a plurality of metal clips (5) each ensuring electrical contact with the shield (4) of a conductor, each clip being electrically connected to the external screen by a conductive bridge (6), characterized in that the external screen comprises a flexible and / or extensible sheath (20).

2. Assembly according to claim 1, comprising a first pair of conductors (CPI) which includes the first conductor (Cl) and a third conductor (C3) and a second pair of conductors (CP2) which includes the second conductor (C2), and a fourth conductor (C4).

3. Assembly according to any one of claims 1 to 2, characterized in that the electrical junction box (1) forms a load-bearing structure to support the external screen.

4. Assembly according to any one of claims 1 to 3, characterized in that the external screen (2) is formed as a flexible wraparound case.

5. Assembly according to any one of claims 1 to 3, characterized in that the outer screen (2) is formed as a two-part housing, capable of being assembled to form a wraparound screen-housing.

6. Assembly according to any one of claims 1 to 5, characterized in that each conductive bridge (6) is formed by a metallic braid.

7. Assembly according to any one of claims 1 to 6, characterized in that the flexible and / or expandable envelope is made of non-welded wire mesh.

8. Assembly according to any one of claims 1 to 7, characterized in that it further provides a grounding clamp, configured to connect the external screen to an electrical ground of the vehicle.

9. Assembly according to any one of claims 1 to 8, further comprising a third pair of conductors (CP3) comprising a fifth conductor (C5) and a sixth conductor (C6).

10. electric or hybrid vehicle including at least one set of electrical connection according to any one of claims 1 to 9.

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