Electrical interconnection device for transmitting electrical power in a vehicle

Abstract

Electrical interconnection device for transmitting electrical power from a first electrical equipment of a vehicle to a second electrical equipment of the vehicle, the electrical interconnection device comprising: an electrically insulating tube (14) having an internal surface delimiting a hollow, and an electrical conductor (8) inserted inside the tube having an external surface in contact with the internal surface. The tube is made of a material expandable by heating, shrinkable by cooling subsequent to heating, crosslinked, and having a temperature class in the range from T2 to T5. Figure for abstract: Fig. 7

Description

Title of the invention: Electrical interconnection device for transmitting electrical power in a vehicle FIELD OF THE INVENTION

[0001] The present invention relates to an electrical interconnection device for transmitting electrical power from a first electrical equipment of a vehicle to a second electrical equipment of the vehicle. STATE OF THE ART

[0002] Conventionally, a vehicle power cable comprises an electrical conductor surrounded by an electrical insulator.

[0003] In use, a current flows through the electrical conductor from an electrical power source to a vehicle in order to charge it. This causes the electrical conductor to heat up. However, excessive heating of the cable is not desirable. It is therefore important to dissipate the heat generated by the flow of current to the outside of the cable.

[0004] Some electrical insulators used in cables have a temperature class of T6. However, these insulators have the disadvantage of being expensive.

[0005] An example of electrical insulation is heat-shrink tubing, i.e. tubing that shrinks when heated. However, the cost of such tubing is high.

[0006] Some insulators have significant variations in external diameter, making it more difficult to connect the cable to equipment in a sealed manner. Description of the invention

[0007] An aim of the invention is to obtain an electrical interconnection device for transmitting electrical power in a vehicle, which is both inexpensive and easy to connect to electrical equipment in a sealed manner.

[0008] This object is achieved by an electrical interconnection device for transmitting electrical power from a first electrical equipment of a vehicle to a second electrical equipment of the vehicle, the electrical interconnection device comprising: an electrically insulating tube having an internal surface delimiting a hollow, and an electrical conductor inserted inside the tube having an external surface in contact with the internal surface. The tube being made of a material expandable by heating, shrinkable by cooling subsequent to heating, crosslinked, and having a temperature class in the range from T2 to T5.

[0009] The fact that the tube is crosslinked gives it better resistance to squeezing. In addition, the expandable nature by heating and shrinkable by subsequent cooling allows the tube to be relatively easily arranged around the electrical conductor, during the manufacture of the interconnection device. This assembly is relatively inexpensive. These properties of the material from which the tube is made therefore make it possible, in combination, to limit variations in the external diameter of the tube. As a result, it is easy to connect the device to the first equipment or to the second equipment in a watertight manner.

[0010] The proposed electrical interconnection device may also include the following optional features, taken alone or in combination whenever possible.

[0011] Preferably, the internal surface of the tube is circular, oval or rectangular.

[0012] Preferably, the temperature class is T4.

[0013] Preferably, the material is flame retardant.

[0014] Preferably, the material is or comprises a polyolefin. The polyolefin is preferably polyethylene, very preferably high density polyethylene.

[0015] Preferably, the electrical conductor is in one piece and extends along an axis, the outer surface is in contact with the inner surface of the tube over 360 degrees in a section plane perpendicular to the axis.

[0016] A method of manufacturing the aforementioned electrical interconnection device is also provided. The method comprises the following steps: • heating the tube to cause the tube to expand, increasing the diameter of the internal surface, and for subsequent cooling of the tube to cause the tube to shrink, reducing the diameter of the internal surface to its initial diameter, • inserting the electrical conductor while the hollow tube insulation is in an expanded state in which the diameter of the inner surface of the tube is greater than the diameter of the outer surface of the electrical conductor, so that, after shrinking the tube, the inner surface of the tube and the outer surface of the electrical conductor are in contact with each other.

[0017] Preferably, the method comprises crosslinking the tube.

[0018] Preferably, the crosslinking of the tube is carried out before the insertion of the electrical conductor inside the tube. DESCRIPTION OF FIGURES

[0019] Other characteristics, aims and advantages of the invention will emerge from the following description, which is purely illustrative and non-limiting, and which must be read in conjunction with the appended drawings in which:

[0020] [Fig.l] schematically illustrates a vehicle and certain components within the vehicle.

[0021] [Fig.2], [Fig.3], [Fig.4], [Fig.5] and [Fig.6] are different cross-sectional views of an electrical interconnection device according to a first embodiment, in different positions along this device.

[0022] [Fig.7] is a partial longitudinal sectional view of the electrical interconnection device according to the first embodiment.

[0023] [Fig.8] is a sectional view of an electrically insulating part in normal and expanded states.

[0024] [Fig.9] is a partial longitudinal sectional view showing the electrically insulating part in the expanded state and other elements of the electrical interconnection device according to the first embodiment, during its manufacture.

[0025] [Fig. 10] is a partial longitudinal sectional view of an electrical interconnection device according to a second embodiment.

[0026] [Fig. 11] is a partial longitudinal sectional view of an electrical interconnection device according to a third embodiment.

[0027] [Fig. 12] is a cross-sectional view of a vehicle electrical interconnection device according to another embodiment.

[0028] Throughout the figures, similar elements bear identical references. DETAILED DESCRIPTION OF THE INVENTION

[0029] In the following, reference will be made to the diameter of certain surfaces which are not necessarily of revolution. In this document, the diameter of a surface which is not of revolution must be understood as the maximum diameter of this surface. 1) Vehicle and power cable

[0030] Referring to [Fig. 1], a vehicle V comprises a first electrical equipment A, a second electrical equipment B, and an electrical interconnection device 1 for transmitting electrical power from the first electrical equipment A to the second electrical equipment B.

[0031] For example, the first electrical equipment A is a source of electrical energy, for example a battery, and the second electrical equipment is intended to be supplied with electrical energy by the first electrical equipment A via the electrical interconnection device 1. In this case, the electrical interconnection device 1 provides an electrical power supply function.

[0032] Alternatively, the first electrical equipment A and the second electrical equipment B are internal components of a battery.

[0033] In the following, we will focus on embodiments in which the electrical interconnection device 1 takes the form of a cable, it being understood that in other embodiments this interconnection device may take the form of a bar.

[0034] The cable 1 comprises three parts 2, 4, 6: a first part 2 (constituting an intermediate part), a second part 4 (constituting a terminal part of the cable 1 suitable for being connected to the first electrical equipment A), and a third part 6 (constituting another terminal part of the cable 1 suitable for being connected to the second electrical equipment B).

[0035] The first part 2 is rigid, in the sense that it tends to retain a specific shape in the absence of external stress. The first part 2 may not be rectilinear. In particular, the first part 2 may comprise one or more bends, as is the case in the example shown in [Fig.l], comprising two bends. The shape assigned to the first part 2 may be determined in advance, so that the first part 2 can be placed in a sinuous gap left free within the vehicle V. Due to the rigidity of its first part 2, the installation of the cable 1 in such a location is facilitated and remains in place.

[0036] The first part 2 may constitute a major part of the cable 1, for example at least 80% of the length of the cable 1 (measured taking into account the changes in direction caused by any bends present).

[0037] The second part 4 extends the first part 2, and has an end intended to be connected to the first electrical equipment A. The second part 4 is more flexible than the first part 2. This means that there is a stress causing a deformation of the first part 2 when this stress is applied to it, but not causing a deformation of the first part 2, comparatively more rigid, when this same stress is applied to the latter. This flexibility allows in practice a technician to adjust the position of the second part 4 relative to the electrical equipment to be connected, thus facilitating this connection.

[0038] The third part 6 also extends the first part 2, and has an end intended to be connected to the second electrical equipment B. Thus, the first part 2 constitutes a connecting part between the second part 4 and the third part 6. The third part 6 is more flexible than the first part 2.

[0039] The second part 4 and the third part 6 may be of identical flexibility (using identical materials of identical sections) or not.

[0040] With reference to [Fig.2], the first part 2 comprises a first electrical conductor 8.

[0041] The first electrical conductor 8 has an internal surface 10 delimiting a hollow 9, and an external surface 12 opposite the internal surface 10, and extending around the internal surface 10. An advantage conferred by this hollow character makes it possible to increase the exchange surface of the first conductor 8 with the air, compared to a more compact conductor such as a strand or a solid conductor (not hollow) of the same conductive section.

[0042] The hollow 9 passes through the first electrical conductor 8 from end to end. Thus, this hollow 9 is accessible by two opposite accesses, and the first electrical conductor 8 has the shape of a tube. The fact that the hollow 9 extends from end to end makes it possible to further increase the exchange surface of the first conductor 8 with the air.

[0043] The first electrical conductor 8 has a rectangular section. By “rectangular section” is meant a section comprising four sides, including two parallel first sides and two parallel second sides, the second sides being perpendicular to the first sides. Thus, in the present disclosure, a “rectangular section” may comprise rounded corners. In this rectangular section, the inner surface 10 forms a rectangular line, and the outer surface 12 forms another rectangular line.

[0044] The first part 2 further comprises a first electrical insulator 14 extending around the first electrical conductor 8.

[0045] The first electrical insulator 14 comprises an inner surface 16 in contact with the outer surface 12 of the first electrical conductor 8, and an outer surface 18 opposite the inner surface 16.

[0046] The first electrical insulator 14 is made of a material which expands when heated.

[0047] Furthermore, the first electrical insulator 14 preferably has a temperature class equal to T3, T4 or T5, very preferably T4.

[0048] Although a class T2 insulator is conceivable, a class T2 insulator has a lower maximum operating temperature and is therefore not capable of operating at higher temperatures, and therefore cannot sustainably withstand heat generated by a significant electric current carried in the first electrical conductor 8. The class T3, T4 or T5 insulator has a higher maximum operating temperature, which allows it to dissipate an electric current carried by the first electrical conductor 8 more efficiently. Thus, at constant current, it is possible to reduce the cross-section of the first part 2.

[0049] Furthermore, a class T3, T4 or T5 insulator is less expensive than a class T6 insulator.

[0050] Ultimately, temperature classes T3, T4 and T5 offer a good compromise between cost and performance. Class T4 offers an ideal compromise.

[0051] Preferably, the first electrical insulator 14 is preferably made of a material being or comprising a polyolefin, or even polyethylene.

[0052] Very preferably, this polyethylene is a high density polyethylene (HDPE). This gives more rigidity to the first electrical insulator 14 than a low density polyethylene.

[0053] The first electrical insulator 14 may be made of polyethylene. Alternatively, the first electrical insulator comprises polyethylene, ethylene vinyl acetate (EVA), or even is made of PE and EVA.

[0054] Furthermore, the first electrical insulator 14 is crosslinked, which also contributes to increasing its rigidity, compared to a non-crosslinked insulator.

[0055] Furthermore, the first electrical insulator 14 may be flame retardant. This flame retardant nature may be the result of fillers present in the polyethylene from which this insulator is made.

[0056] The first electrical insulator 14 may form an outer layer of the cable 1. In other words, the first electrical insulator 14 forms a sheath of the cable 1, is not surrounded by another layer and is therefore visible from the outside of the cable 1. Alternatively, the cable 1 comprises other layers extending around the first electrical insulator 14, for example an outer sheath, or even an additional electrical conductor between such an outer sheath and the electrical insulator.

[0057] Preferably, the first part 2 of the cable 1 is devoid of an electromagnetic shielding layer around the first electrical insulator 14.

[0058] With reference to [Fig.3], the second part 4 comprises a second electrical conductor 20 suitable for being electrically connected to the electrical equipment A.

[0059] The second electrical conductor 20 has an external surface 22.

[0060] The external surface 22 of the second electrical conductor 20 has a diameter less than that of the external surface 12 of the first electrical conductor 8.

[0061] The second electrical conductor 20 may be solid or hollow. When it is solid, the second electrical conductor 20 has no internal surface; when it is hollow, the second electrical conductor 20 is provided with an internal surface opposite the external surface 22, similarly to the first electrical conductor 8.

[0062] In particular, the second electrical conductor 20 may be in the form of a strand. In a manner known per se, a strand comprises a set of contiguous elements rotating around a main axis, for example in a helical manner.

[0063] Preferably, the second electrical conductor 20 is made of copper strand. This conductor construction has the advantage of being particularly flexible, and therefore contributes to the flexible nature of the second part 4. In addition, the copper composition of the strand makes it possible to avoid the risk of galvanic corrosion. Consequently, this copper strand construction contributes to facilitating the connection and the service life of the second part 4 to the first electrical equipment A.

[0064] The second part 4 also comprises a second electrical insulator 24 surrounding the second electrical conductor 20.

[0065] The second electrical insulator 24 comprises an internal surface 26 opposite the external surface 22 of the second electrical conductor 20, and an external surface 28 opposite the internal surface 26.

[0066] The internal surface 26 has a diameter identical to that of the internal surface 16 of the first electrical insulator 14. Furthermore, the external surface 28 has a diameter identical to that of the external surface 18 of the first electrical insulator 14. A space 23 separates the second electrical conductor 20 from the second electrical insulator 24.

[0067] The second electrical insulator 24 is made of the same material as the first electrical insulator 14. All the information provided above in relation to the material of the first electrical insulator is applicable to the second electrical insulator 24 (temperature class, nature of the material used, etc.).

[0068] The second electrical insulator 24 may form an outer layer of the cable 1. In other words, the second electrical insulator 24 forms a sheath of the cable 1, is not surrounded by another layer and is therefore visible from the outside of the cable 1. Alternatively, the cable 1 comprises other layers extending around the second electrical insulator 24, for example an outer sheath, or even an additional electrical conductor between such an outer sheath and the electrical insulator.

[0069] The second electrical insulator 24 and the first electrical insulator 14 are two single-piece parts extending along the first part 2 and the second part 4.

[0070] We have seen previously that the second part 4 was more flexible than the first part 2. This difference in flexibility can in particular be found at the level of the electrical conductors. Thus, the second electrical conductor 20 can be more flexible than the first electrical conductor 8.

[0071] Preferably, the second part 4 of the cable 1 is devoid of an electromagnetic shielding layer around the second electrical conductor 20.

[0072] Since the second part 4 of the electrical interconnection device 1 is more flexible than the first part 2, the latter can be more easily aligned with the first equipment A. On the other hand, the first part 2 benefits from the advantages associated with its rigidity. In addition, bringing the internal surface 10 of the first electrical conductor 8 and the external surface 22 of the second electrical conductor 20 into contact has the advantage of allowing fixing and electrical connection between the two conductors 8, 20 without requiring an additional connecting part such as a sleeve.

[0073] With reference to [Fig.4], the second electrical conductor 20 extends partially into the hollow 9 delimited by the first electrical conductor 8, so that the internal surface 10 of the first conductor 8 is in contact with the external surface 22 of the second conductor 20.

[0074] This contact is carried out in such a way as to ensure relative fixity between the first electrical conductor 8 and the second electrical conductor 20. Furthermore, this contact is direct (i.e. without an element inserted between the two surfaces 10 and 22), so as to ensure an electrical connection between the first electrical conductor 8 and the second electrical conductor 20. This relative fixity and this electrical connection can be obtained by different techniques, in particular by crimping or welding.

[0075] The external surface 22 of the second electrical conductor 20 may be complementary to the internal surface 10 of the first electrical conductor 8, so that this contact is effective around the entire periphery of the second electrical conductor 20.

[0076] With reference to [Fig.5], the third part 6 comprises a third electrical conductor 30 suitable for being electrically connected to the other electrical equipment.

[0077] The third electrical conductor 30 has an external surface 32.

[0078] The external surface 32 of the third electrical conductor 30 has a diameter less than that of the internal surface 12 of the first electrical conductor 8.

[0079] The third electrical conductor 30 may be solid or hollow. When it is solid, the third electrical conductor 30 has no internal surface; when it is hollow, the third electrical conductor 30 has an internal surface opposite the external surface 32, similarly to the first electrical conductor 8.

[0080] In particular, the third electrical conductor 30 may be in the form of a strand.

[0081] Preferably, the third electrical conductor 30 is made of copper. This material has the advantage of being particularly flexible, and therefore contributes to the flexible nature of the third part 6. Consequently, this material contributes to facilitating the connection of the second part 6 to the second electrical equipment B.

[0082] The third part 6 also comprises a third electrical insulator 34 surrounding the third electrical conductor 30.

[0083] The third electrical insulator 34 comprises an internal surface 36 opposite the external surface 32 of the third electrical conductor 30, and an external surface 38 opposite the internal surface 36.

[0084] The internal surface 36 has a diameter identical to that of the internal surface 16 of the first electrical insulator 14. Furthermore, the external surface 38 has a diameter identical to that of the external surface 18 of the first electrical insulator 14. A space 33 separates the third electrical conductor 30 from the third electrical insulator 34.

[0085] The third electrical insulator 34 is made of the same material as the first electrical insulator 14. All the information provided above in relation to the material of the first electrical insulator is applicable to the third electrical insulator 34 (temperature class, nature of the material used, etc.).

[0086] The third electrical insulator 34 may form an outer layer of the cable 1. In other words, the third electrical insulator 34 forms a sheath of the cable 1, is not surrounded by another layer and is therefore visible from the outside of the cable 1. Alternatively, the cable 1 comprises other layers extending around the third electrical insulator 34, for example an outer sheath, or even an additional electrical conductor between such an outer sheath and the electrical insulator.

[0087] The third electrical insulator 34 and the first electrical insulator 14 are two single-piece parts extending along the first part 2 and the third part 6.

[0088] We have seen previously that the third part 6 was more flexible than the first part 2. This difference in flexibility can in particular be found at the level of the electrical conductors. Thus, the third electrical conductor 30 can be more flexible than the first electrical conductor 8.

[0089] Preferably, the third part 3 of the cable 1 is devoid of an electromagnetic shielding layer around the third electrical conductor 30.

[0090] As the third part 6 of the electrical interconnection device 1 is more flexible than the first part 2, the latter can be more easily aligned with the second equipment B. On the other hand, the first part 2 benefits from the advantages associated with its rigidity. In addition, bringing the internal surface 10 of the first electrical conductor 8 and the external surface 32 of the third electrical conductor 30 into contact has the advantage of allowing fixing and electrical connection between the two conductors 8, 30 without requiring an additional connecting part such as a sleeve.

[0091] With reference to [Fig.6], the third electrical conductor 30 extends partially into the hollow 9 delimited by the first electrical conductor 8, so that the internal surface 10 of the first electrical conductor 8 is in contact with the external surface 32 of the third electrical conductor 30.

[0092] This contacting is carried out so as to ensure relative fixity between the first electrical conductor 8 and the third electrical conductor 30. Furthermore, this contacting is direct (i.e. without any element inserted between the two surfaces), so as to ensure an electrical connection between the first electrical conductor 8 and the third electrical conductor 30. This relative fixity and this electrical connection can be obtained by different techniques, in particular by crimping or welding.

[0093] The external surface 32 of the third electrical conductor 30 may be complementary to the internal surface 10 of the first electrical conductor 8, so that this contact is effective around the entire periphery of the third electrical conductor 30.

[0094] [Fig.7] is a schematic longitudinal sectional view showing the through-hollow 9 in which the second electrical conductor 20 and the third conductor electrical conductors 30 are inserted and partially extend. Of course, it is not necessary for these insertions to be so deep as to fill the entire through-hollow 9, i.e. such that the second electrical conductor 20 and the third electrical conductor 30 touch each other. To save conductive material, the second electrical conductor 20 and the third electrical conductor 30 occupy only a portion of the space available in the hollow, and thus remain at a distance from each other.

[0095] As previously indicated, the first electrical insulator 14, the second electrical insulator 24 and the third electrical insulator 34 constitute different parts of an electrically insulating part extending in the first part 2, in the second part 4 and in the third part 6 of the cable 1. The first part 2, the second part 4 and the third part 6 have identical respective external diameters. Such a constant diameter contributes to making the cable easier to connect in a sealed manner to other equipment.

[0096] Due to the radial thickness of the first electrical conductor 8, this electrically insulating part may comprise a shoulder forming the junction between the first electrical insulator 14 and the second electrical insulator 24, and another shoulder forming the junction between the first electrical insulator 14 and the third electrical insulator 34 (visible in [Fig.7]).

[0097] 2) Method of manufacturing an electrical interconnection device

[0098] A method of manufacturing the electrical interconnection device 1 for a vehicle described above comprises the following steps.

[0099] As a preliminary step, the first electrical conductor 8, the second electrical conductor 20 and the third electrical conductor 30 were manufactured.

[0100] In an insertion step, the second electrical conductor 20 is partially inserted into the hollow delimited by the first electrical conductor 8, so that the external surface 22 of the second electrical conductor 20 is in contact with the internal surface 10 of the first electrical conductor 8.

[0101] In another insertion step, the third electrical conductor 30 is partially inserted into the hollow delimited by the first electrical conductor 8, so that the external surface 32 of the third electrical conductor 30 is in contact with the internal surface 10 of the first electrical conductor 8.

[0102] In a fixing step, a treatment is carried out to fix the second electrical conductor 20 to the first electrical conductor 8.

[0103] The treatment may comprise mechanical crimping of the second electrical conductor 20 in the first electrical conductor 8. Thus, it is the application of a force which makes it possible to ensure this relative fixity between the first electrical conductor 8 and the second electrical conductor 20.

[0104] Alternatively, the treatment comprises magnetic pulse welding. Under the effect of such magnetic pulses, bonds are created at the atomic level between the inner surface and the outer surface, and these bonds make it possible to obtain the expected fixity.

[0105] In another variant, the treatment comprises ultrasonic welding.

[0106] The fixation treatment carried out may combine several of the aforementioned techniques.

[0107] In another fixing step, a treatment is carried out to fix the third electrical conductor 30 to the first electrical conductor 8. This treatment may be identical to that used to fix the second electrical conductor 20 to the first electrical conductor 8. The two fixing treatments may be simultaneous or consecutive.

[0108] In an electrical insulation step, the first electrical insulator 14 is positioned around the first electrical conductor 8, such that the inner surface 16 of the first electrical insulator 14 is in contact with the outer surface 10 of the first electrical conductor 8. Furthermore, the second electrical insulator 24 is positioned around the second electrical conductor 20, such that the inner surface 26 of the second electrical insulator 24 is in contact with the outer surface 22 of the second electrical conductor 20. Furthermore, the third electrical insulator 34 is positioned around the third electrical conductor 30, such that the inner surface 36 of the third electrical insulator 34 is in contact with the outer surface 32 of the third electrical conductor 30.

[0109] The electrical insulation step comprises the following sub-steps, when the first electrical insulator 14, the second electrical insulator 20 and the third electrical insulator 30 come from a single electrically insulating part.

[0110] [Fig.8] shows an example of a hollow electrically insulating part 40.

[0111] The electrically insulating part 40 is a hollow tube extending around an axis (it is not obligatory for the shape of the section of this part to correspond exactly to the shape of the section of the electrical conductors). The electrically insulating part 40 has an internal surface delimiting the hollow. This internal surface has a circular profile, but this profile could alternatively be oval or rectangular. The first electrical insulator 14, the second electrical insulator 20 and the third electrical insulator 30 correspond to different parts of the part 40, and are therefore each tubes.

[0112] In a crosslinking sub-step, the electrically insulating part 40 undergoes crosslinking. The crosslinking has the effect of improving the finishing resistance of the part 40.

[0113] In a heating sub-step, the crosslinked electrically insulating part is heated, so as to cause expansion of the electrically insulating part, thereby increasing the diameter of its internal surface, as shown in [Fig.8]. electrically insulating part is then in an expanded state, and the diameter of its internal surface is greater than the diameter of the external surface of the first electrical conductor 8, the second electrical conductor 20 and the third electrical conductor 30.

[0114] In a positioning sub-step, the electrically insulating part 40 in its expanded state is positioned around the first electrical conductor 8, the second conductor 20 and the third conductor 30 such that its internal surface faces the external surfaces 12, 22, 32 of the electrical conductors present (see [Fig. 10]). This positioning is easily done given the expanded state of the electrically insulating part.

[0115] In a cooling sub-step, the electrically insulating part 40 is cooled, thereby causing a shrinkage reducing the diameter of its internal surface.

[0116] During this retraction, the internal surface of the electrically insulating part 40 comes into contact with the external surface 12 of the first electrical conductor 8 so as to match its shape. The external surface 12 thus comes into contact with the internal surface of the part 40 over 360 degrees in a section plane perpendicular to the longitudinal axis of the part 40. In other words, there is a section plane in which the contact between the part 40 and the first electrical conductor 8 is established all around the axis, over 360 degrees.

[0117] On the other hand, the internal surface of the electrically insulating part 40 does not come into contact with the external surface 22 of the first electrical conductor 20 or with the external surface 32 of the second electrical conductor 30. This results from the fact that the part 40 is rigid, this rigidity itself being obtained thanks to the material in which the part 40 is made, and improved by the crosslinking carried out upstream.

[0118] The cooling of the electrically insulating part 40 can be active cooling (by immersing the electrically insulating part in a cold environment) or passive cooling (by simply ceasing heating and waiting sufficiently to cause retraction).

[0119] The preceding steps are carried out while the conductors and insulators are rectilinear. They therefore make it possible to obtain a device 1 taking the form of a cable or a rectilinear bar.

[0120] In a shaping step, the final shape of the electrical interconnection device 1 is obtained by shaping the first part of the electrical interconnection device 1. The device 1 as shown in [Fig.l] is thus obtained. It can then be installed in the vehicle V, and be connected to the electrical equipment A, B, for the purpose of transmitting electrical power from A to B (or vice versa).

[0121] During the process described above, the electrically insulating part was crosslinked 40 before assembling it with electrical conductors. Carrying out crosslinking at this preliminary stage is particularly easy. Indeed, it is possible to move the electrically insulating part with pulleys, in order to expose it to a crosslinking device, which irradiates radiation towards the part 40. This radiation crosslinks the wall of the part 40 opposite the crosslinking device, and is also capable of passing through the hollow of the part 40, and crosslinking the opposite wall of the part 40. Since the part is not yet assembled with conductors, such conductors do not hinder the propagation of the radiation in the hollow.

[0122] An advantage of the above method is that it makes it possible to obtain a cable whose external diameter does not vary or varies very little along the cable. This gives the cable the ability to be connected in a repeatable and watertight manner to electrical equipment.

[0123] This advantage is obtained in particular compared to a process in which an insulator is formed by extrusion. External diameter variations are due to the fact that variations in the quantity of insulator injected into the extrusion head cause a variation in the outside diameter in the case of extrusion onto a conductor. In the case of extrusion of a hollow tube, these variations in the quantity injected affect the inside diameter while leaving the outside diameter uniform. This uniformity at constant tightening in the connector certainly allows for uniform sealing from part to part. But in the case of variation in the outside diameter (case of the conductor with extrusion) the variation at constant tightening causes variability in the sealing. The manufacture of the “empty” insulating part 40 thus allows for increased control of the outside diameter compared to an insulator deposited via conventional extrusion onto a conductor.Variations in material input are reflected in the internal (not external) diameter of the insulating tube during a tube manufacturing process not supported by a conductor. 3) Implementation variants

[0124] In the cable embodiment 1 discussed so far, the first electrical conductor 8 has a through-hollow in which the second electrical conductor 20 and the third electrical conductor 30 are inserted and partially extend. In another embodiment, the first electrical conductor 8 is partially solid, and has two mutually opposite blind holes. In other words, the first conductor comprises two terminal portions each having a blind hole, and a solid central portion separating the two blind holes from each other. Thus, each blind hole has a bottom which marks the boundary between the terminal portion considered and the solid central portion of the electrical conductor 8. The second electrical conductor 20 extends into one of the two blind holes, and the third electrical conductor 30 extends into the opposite blind hole.Thus, unlike the previous embodiment, the second electrical conductor 20 and the third electrical conductor 30 are here separated by the solid central part of the first. electrical conductor 8.

[0125] A second embodiment for the cable 1 is shown in [Fig. 10]. In this second embodiment, the inner surface 26 of the second electrical insulator 24 is in contact with the outer surface 22 of the second electrical conductor 20. The hollows 23 and 33 are therefore absent or in any case minimized. Furthermore, the inner surface 36 of the third electrical insulator 34 is in contact with the outer surface 32 of the third electrical conductor 30. In the second embodiment, the electrically insulating part 40 comprises a shoulder forming the junction between the first electrical insulator 14 and the second electrical insulator 24, and another shoulder forming the junction between the first electrical insulator 14 and the third electrical insulator 34.

[0126] The cable according to the second embodiment can be obtained by a method during which the first electrical insulator 14, the second electrical insulator 24 and the third electrical insulator 34 are formed by extrusion around the electrical conductors.

[0127] A third embodiment for the cable 1 is shown in [Fig. 11]. In this third embodiment, the first electrical insulator 14 and the second electrical insulator 24 are different parts. An additional insulating sleeve (not shown) may overlap the first electrical insulator 14 and the second electrical insulator 24, in order to plug a gap left between the first electrical insulator 14 and the second electrical insulator 24. Similarly, the third electrical insulator 34 and the first electrical insulator 14 may be different parts. Another additional insulating sleeve (not shown) may overlap the first electrical insulator 14 and the third electrical insulator 34, in order to plug a gap left between the first electrical insulator 14 and the third electrical insulator 34.Instead of using such sleeves, it is also possible to have the first electrical insulator 14 cover the second electrical insulator 24 and / or the third electrical insulator 34.

[0128] The cable according to the third embodiment can be obtained by the method similar to that applied to the first embodiment, by repeating the heating steps to each of the three electrical insulators. It is possible to shrink the second electrical insulator 24 onto the second electrical conductor 20 before inserting one end of the second electrical conductor 20, left bare, into the first hollow electrical conductor 8. Similarly, it is possible to shrink the third electrical insulator 34 onto the third electrical conductor 30 before inserting one end of the third electrical conductor 30, left bare, into the first hollow electrical conductor 8.

[0129] The electrical conductors 8, 20, 30 shown in Figures 2, 3 and 4 have a rectangular section. Such a section promotes bending of the cable 1 in one or two preferred directions, which can facilitate the implementation of the shaping step, when very specific cable shapes are desired. [Fig. 12] shows a variant in which the electrical conductors 8, 20, 30 have respective circular sections. These circular sections allow the cable 1 to be bent in the shaping step in any direction; thus, the cable can be easily shaped into a greater number of shapes than with a rectangular section. This variant is applicable to all the embodiments described previously. Oval sections are also conceivable.

Claims

Claims

1. Electrical interconnection device for transmitting electrical power from a first electrical equipment of a vehicle to a second electrical equipment of the vehicle, the electrical interconnection device comprising: • an electrically insulating tube (14) having an internal surface delimiting a hollow, the tube being made of a material: • expandable by heating and shrinkable by cooling subsequent to heating, • crosslinked, and • having a temperature class in the range from T2 to T5; and • an electrical conductor (8) inserted inside the tube, and having an external surface in contact with the internal surface.

2. An electrical interconnection device according to the preceding claim, wherein the internal surface of the tube is circular, oval or rectangular.

3. An electrical interconnection device according to any preceding claim, wherein the temperature class is T4.

4. An electrical interconnection device according to any preceding claim, wherein the material is flame retardant.

5. An electrical interconnection device according to any preceding claim, wherein the material is or comprises a polyolefin.

6. An electrical interconnection device according to the preceding claim, wherein the polyolefin is a high density polyethylene.

7. An electrical interconnection device according to any preceding claim, wherein the electrical conductor is in one piece and extends along an axis, the outer surface is in contact with the inner surface of the tube over 360 degrees in a section plane perpendicular to the axis.

8. A method of manufacturing an electrical interconnection device according to any preceding claim, the method including the following steps: • heating the tube to cause the tube to expand, increasing the diameter of the internal surface, and for subsequent cooling of the tube to cause the tube to shrink, reducing the diameter of the internal surface to its initial diameter, • inserting the electrical conductor while the hollow tube insulation is in an expanded state in which the diameter of the inner surface of the tube is greater than the diameter of the outer surface of the electrical conductor, so that, after shrinking the tube, the inner surface of the tube and the outer surface of the electrical conductor are in contact with each other.

9. Method according to the preceding claim, comprising crosslinking the tube.

10. Method according to the preceding claim, in which the crosslinking of the tube is carried out before the insertion of the electrical conductor inside the tube.