Interconnector for electrical machine, and electrical machine including the interconnector

Abstract

The invention relates to an interconnector (37) for an electrical machine (1), the interconnector (37) comprising a support structure (40) having an annular shape centered around an axis X and a first connecting wire (50), a second connecting wire (60), and a third connecting wire (70) which are supported by the support structure (40). The first connecting wire (50), the second connecting wire (60), and the third connecting wire (70) each have N folded portions (53, 63, 73) projecting from the support structure (40), where N is an integer greater than or equal to 2. The folded portions (53, 63, 73) of the first connecting wire (53), the second connecting wire (63), and the third connecting wire (73) are arranged periodically around the axis X. (See Figure 4 for abbreviations.)

Description

Title of the invention: Interconnector for electrical machine, and electrical machine comprising the interconnector technical field

[0001] The invention relates to an interconnector for an electrical machine and an electrical machine, in particular for an electric or hybrid vehicle, comprising this interconnector. The invention also relates to an assembly comprising a reduction device and such an electrical machine. Technological background

[0002] A stator of a rotating electrical machine comprises a plurality of coils distributed around the axis of rotation of the machine, each coil having a winding. In order to achieve the desired excitation of the coils, the windings are connected, on the one hand, to each other according to a given connection (for example, star or delta connection) and, on the other hand, to an electrical connector of the electrical machine by means of an interconnector. The interconnector comprises an annular support and annular copper strips onto which are soldered connecting portions, also made of copper, suitable and intended to be connected to the terminal ends of the windings.

[0003] However, such interconnectors are not entirely satisfactory, particularly in that their production is long and costly. Summary of the invention

[0004] One idea underlying the invention is to provide an interconnector that is simple and inexpensive to manufacture and is also easy to connect to the windings of the electrical machine.

[0005] According to one embodiment, the invention provides an interconnector for an electrical machine, the interconnector comprising: - a support structure having an annular shape centered around an X-axis and comprising a first connector, a second connector, and a third connector; and - a first connecting wire, a second connecting wire, and a third connecting wire which are supported by the support structure, in which the first connecting wire runs from the first connector around the X-axis to return to the first connector, in which the second connecting wire runs from the second connector around the X-axis to return to the second connector, in which the third connecting wire runs from the third connector around the X-axis back to the third connector, the first connecting wire, the second connecting wire and the third connecting wire each having N folded portions protruding from the support structure, each folded portion being suitable and intended to be connected to a terminal end of a winding of the electrical machine, where N is an integer greater than or equal to 2, the folded portions of the first connecting wire, the second connecting wire and the third connecting wire being arranged periodically around the X-axis.

[0006] Such an interconnector can be manufactured in a limited number of simple steps, and therefore at low cost. The folded portions of the connecting wires allow the windings of the electrical machine to be easily connected to the connecting wires by contact between a terminal end of a winding and a folded portion. Furthermore, since the folded portions are arranged periodically around the X-axis, the first, second, and third connecting wires can each correspond to one of the phases U, V, W of the electrical machine.

[0007] According to embodiments, such an interconnector may include one or more of the following characteristics.

[0008] According to one embodiment, the folded portions protrude axially from the support structure.

[0009] In this way, it is particularly easy to connect the windings of two axially offset stators to the connecting wires.

[0010] According to one embodiment, the first connecting wire, the second connecting wire and the third connecting wire are each made by forming a wire.

[0011] According to one embodiment, the wire is a round wire.

[0012] This tends to facilitate wire forming and therefore the manufacture of connecting wires.

[0013] According to one embodiment, the wire is a round enameled wire, the round enameled wire being stripped at the level of all or part of the folded portions.

[0014] Thus, the enamel of the round wire forms a layer of electrical insulation on the surface of the connecting wires, except at the level of all or part of the folded portions.

[0015] According to one embodiment, the first connecting wire, the second connecting wire, and the third connecting wire each comprise Nl wire portions between two consecutive folded portions, the support structure comprises a groove and first, second, and third stepped portions positioned radially outside the groove and extending respectively in a first, second, and third support planes orthogonal to the X-axis, the folded portions being supported by the stepped portions and the wire portions running in or along the groove, and the first, second, and third planes are axially offset and the Nl wire portions of the first connecting wire are axially offset relative to the Nl wire portions of the second connecting wire and the Nl wire portions of the second connecting wire are axially offset relative to the Nl wire portions of the third connecting wire.

[0016] The groove facilitates the positioning of the connecting wires on the support structure during the manufacture of the interconnector. Furthermore, the axial offset of the wire segments ensures that the connecting wires do not come into contact with each other. Therefore, it is not necessary to place electrical insulation on the support structure between the wire segments, particularly if the connecting wires are each made by forming a round enameled wire. This further simplifies the manufacture of the interconnector.

[0017] According to one embodiment, at least some of the stepped portions have a lug arranged to block one of the first connecting wire, the second connecting wire and the third connecting wire from rotating around the X axis.

[0018] According to one embodiment, the support structure is made of a polymer material. In one embodiment, the lugs are hot-formed so as to block the first connecting wire, the second connecting wire, and the third connecting wire from translation along the X-axis.

[0019] This tends to further facilitate the positioning of the connecting wires on the support structure during the manufacture of the interconnector.

[0020] According to one embodiment, the interconnector further comprises a neutral wire, the neutral wire having 3N folded portions projecting from the support structure along the X axis, the folded portions of the neutral wire being arranged alternately with the folded portions of the first connecting wire, the second connecting wire and the third connecting wire around the X axis.

[0021] Such a neutral wire can correspond to the neutral of the electrical machine while the first, second and third connecting wires can each correspond to one of the phases U, V, W of the electrical machine.

[0022] According to one embodiment, the neutral wire is made by forming a round enameled wire, the round enameled wire being stripped at the level of all or part of the folded portions.

[0023] According to one embodiment, the invention also provides an electrical machine comprising: - a rotor fixed in rotation to a rotor shaft, the rotor shaft being movable in rotation around an axis of rotation; - a first stator, the first stator comprising a plurality of first coils, each having a first winding, arranged around the axis of rotation; and - an interconnector to connect the windings of the first coils to each other and to a power source, such as an inverter, in which: The interconnector is, according to any one of the embodiments described above, the X axis of the interconnector support structure is parallel to the axis of rotation, the folded portions of the first connecting wire, the second connecting wire and the third connecting wire are each connected to a first winding by contact with a first terminal portion that comprises said first winding.

[0024] Such an electrical machine is simple and inexpensive to manufacture since the interconnector is itself simple and inexpensive to manufacture. Furthermore, the folded portions of the connecting wires allow the windings of the electrical machine to be easily connected to the connecting wires.

[0025] According to one embodiment, the X axis of the interconnector support structure coincides with the axis of rotation.

[0026] According to an embodiment in which the interconnector includes the aforementioned neutral wire, the folded portions of the neutral wire are each connected to one of the first windings by contact with a second terminal portion comprising said first winding.

[0027] According to one embodiment, the electric machine further comprises a second stator, the first stator and the second stator being arranged axially on either side of the rotor, the second stator comprising a plurality of second coils, each of which has a second winding and which are arranged around the axis of rotation, and the folded portions of the first connecting wire, the second connecting wire and the third connecting wire are each connected to one of the second windings by contact with a first terminal portion comprising said second winding.

[0028] According to one embodiment, the electric machine further comprises a first half-casing, the first stator being housed in the first half-casing.

[0029] According to one embodiment, the interconnector support structure is referred to the first half of the housing.

[0030] According to the embodiment, the interconnector support structure is formed as a single unit with the first half of the housing.

[0031] According to one embodiment, the electric machine includes a second half-casing which is fixed to the first half-casing, the second half-casing defining with the first half-casing a housing space in which the first stator and the rotor are housed.

[0032] According to one embodiment, the second half-casing has an opening, a front portion of the rotor shaft passing through the opening.

[0033] According to one embodiment, the second half-casing has a plurality of windows arranged around the axis of rotation, the folded portions of the first connecting wire, the second connecting wire and the third connecting wire passing through the windows so as to protrude towards the front portion of the rotor shaft along the X axis.

[0034] According to one embodiment, the invention also provides an assembly comprising the electric machine including the aforementioned first half-casing and second half-casing and a reduction device, the reduction device comprising a bell fixed to the first half-casing and / or the second half-casing, the bell covering the second half-casing.

[0035] According to one embodiment, the folded portions have a hairpin shape. Brief description of the figures

[0036] The invention will be better understood, and other objects, details, features and advantages thereof will become more apparent from the following description of several particular embodiments of the invention, given solely by way of illustration and not limitation, with reference to the accompanying drawings.

[0037] [Fig-1] The [Fig.1] is a perspective view of an electrical machine.

[0038] [Fig.2] Fig.2 is a perspective view of the electrical machine, without a half- The casing of the electric machine has been omitted in order to show internal components of the electric machine.

[0039] [Fig. 3] Fig. 3 is a perspective view of an interconnector comprising the electric machine.

[0040] [Fig.4] The [Fig.4] is an exploded view of the interconnector.

[0041] [Fig.5] The [Fig.5] is a partial cross-sectional view of the interconnector.

[0042] [Fig.6] Fig.6 is a partial perspective view of the interconnector, before Hot forming of an interconnector lug on the left view and after hot forming of the lug on the right view.

[0043] [Fig.7] Fig.7 is a partial perspective view of the electrical machine, showing more specifically the connections between the interconnector and the windings of the electrical machine. Description of the implementation methods

[0044] In the description and claims, the terms "external" and "internal" and the orientations "axial" and "radial" shall be used to designate, according to the definitions given in the description, elements of the electrical machine. By convention, the X-axis of rotation of the rotor defines the "axial" orientation. The terms "external" and "internal" are used to define the relative position of one element with respect to another, with reference to the X-axis. An element close to the X-axis is thus described as internal, as opposed to an external element located radially at the periphery.

[0045] In the example described below, the electric machine 1 is a permanent magnet synchronous machine. It can notably be used as a motor to power an electric or hybrid vehicle and / or as a generator for such a vehicle.

[0046] An electrical machine 1 is shown in perspective in [Fig. 1] and [Fig. 2]. The electrical machine 1 comprises a casing 3 which includes a first half-casing 9 and a second half-casing 4 fixed to each other, a rotor 17, a first stator 16 and a second stator 18. In [Fig. 2], the second half-casing 4 has been omitted in order to show the first stator 16 and the second stator 18.

[0047] The rotor 17 is fixed in rotation to a rotor shaft 8. The X axis of rotation of the rotor shaft 8 is indicated in dotted lines on [Fig.1] and [Fig.2].

[0048] The first stator 16 and the second stator 18 are arranged axially on either side of the rotor 17. The rotor 17 comprises a rotor disk 17D on which are fixed a plurality of permanent magnets distributed around the X axis.

[0049] On the other hand, as can be seen in [Fig.1] and [Fig.2], the first half-case 9 has a radially oriented bottom 10 and a peripheral rim 11 which extends axially from the bottom 10. As can be seen in [Fig.2], the peripheral rim 11 surrounds the first stator 16, so that the first stator 16 is housed in the first half-case 9.

[0050] As can be seen in [Fig.1], the second half-casing 4 has an outer skirt 5 and a bottom wall 6. The bottom wall 6 of the second half-casing 4 has an opening 7 allowing the passage of the rotor shaft 8. As can be seen in [Fig.1], the second half-casing 4 defines with the first half-casing 9 a housing space in which the first stator 16, the rotor 17 and the second stator 18 are housed.

[0051] The half-casings 9, 4 are fixed to each other by means of fasteners 12, such as fixing screws. The fasteners 12 pass through openings formed in fixing lugs 13, 14 which project radially from the peripheral rim 11 of the first half-casing 9 and from the outer skirt 5 of the second half-casing 4 and which are regularly distributed around the axis X.

[0052] The electric machine 1 can, for example, be associated with a reduction device. In this case, one end 8A, here splined, of the rotor shaft 8 is coupled with an input shaft of the reduction device, and the housing 3 is fixed to a casing of the reduction device. In the example shown, the first half of the housing 9 In addition to the fixing lugs 13, it includes fixing lugs 13R which project radially from the peripheral rim 11. Fastening elements, such as fixing screws, pass through holes provided in the fixing lugs 13R in order to fix the first half-casing 9 to a bell that is part of the housing of the reduction device, the bell being intended to cover the second half-casing 4. Alternatively, the bell can be fixed to the second half-casing 4.

[0053] With reference to [Fig. 2] and [Fig. 7], the stators 16, 18 are now described. The description given for the second stator 18 is also applicable to the first stator 16. The second stator 18 has a plurality of teeth 19. The teeth 19 are, for example, made by stacking sheets of electrical steel. Alternatively, each tooth 19 is made of soft magnetic composite (SMC), in particular obtained by sintering.

[0054] Each tooth 19 carries a coil 22. Each coil 22 has an insulating support 23 which includes a sleeve fitted onto the tooth 19 and two flanges 23a, 23b extending in vertical planes, respectively from one end of the sleeve. The teeth 19 and the coils 22 are fixed to a support structure which includes a flange 25 (see [Fig. 7]).

[0055] The coils 22 also include a winding 24 which is made of wire, for example copper, and is wound around the sheath of the insulating support 23 between the two edges 23a, 23b. The winding 24 has a first terminal end 24P and a second terminal end 24N.

[0056] Furthermore, the electrical machine 1 includes an interconnector 37, which is shown in perspective in [Fig. 3] and in exploded view in [Fig. 4]. As will be detailed below, the interconnector 37 allows, on the one hand, the windings 24 of the coils 22 to be connected to each other and, on the other hand, to be connected to a power socket 38, visible in Figures 1 and 2. The power socket 38 is housed in a recess 39 in the first half of the casing 9, and is intended to be connected to a power source, for example to an electrical circuit of the vehicle, in particular to an inverter included in the vehicle's electrical circuit.

[0057] The interconnector 37 comprises a support structure 40 and three connecting wires 50, 60, 70 which are supported by the support structure 40. As can be seen in [Fig. 3] and [Fig. 4], the support structure 40 has an annular shape centered around the X-axis. The support structure 40 has three connectors 95, 96, 97 associated respectively with the connecting wires 50, 60, 70. In the example shown, the connectors 95, 96, 97 are ring terminals which are housed in the power socket 38.

[0058] The connecting wire 50 travels from connector 95 around the X-axis and back to connector 95. More specifically, the connecting wire 50 has a first end portion 51 and second end portion 52 which are plugged into connector 95, and connecting wire 50 describes a continuous curve from end portion 51 to end portion 52 around the X axis. Similarly, connecting wire 60 has a first end portion 61 and a second end portion 62 which are plugged into connector 96 and runs from connector 96 around the X axis to return to connector 96, and connecting wire 70 has a first end portion 71 and a second end portion 72 which are plugged into connector 97 and runs from connector 97 around the X axis to return to connector 97.

[0059] Furthermore, the connecting wires 50, 60, 70 have N folded portions 53, 63, 73 that project axially from the support structure 40. In the embodiment shown, the folded portions 53, 63, 73 are particularly hairpin-shaped. However, other shapes are also possible. In the example shown, N = 8. Alternatively, N is any integer greater than or equal to 2. As can be seen more clearly in [Fig. 3], the folded portions 53, 63, 73 are arranged periodically around the X axis. In other words, by traversing the annular shape of the support structure 40 around the X axis and considering the folded portions 53, 63, 73, one successively encounters a folded portion 53, then a folded portion 63, then a folded portion 73, then again a folded portion 53, etc.In other words, a pattern consisting of a folded portion53, a folded portion63, and a folded portion73 is repeated N times around the X axis.

[0060] Since the connecting wires 50, 60, 70 are continuous between their end portions 51 and 52, 61 and 62, 71 and 72, the connecting wires 50, 60, 70 further comprise Nl portions of wire 54, 64, 74, each portion of wire 54, 64, 74 being between two consecutive folded portions 53, 63, 73.

[0061] With reference now to [Fig. 5] and [Fig. 6], the support structure 40 has a groove 43, and the wire segments 54, 64, 74 run in the groove 43 or directly above the groove 43. In the example shown, the wire segments 54, 64 run in the groove 43 while the wire segments 74 run directly above the groove 43. Furthermore, as can be seen in [Fig. 5], the wire segments 54 are axially offset relative to the wire segments 64, and the wire segments 64 are axially offset relative to the wire segments 74.

[0062] On the other hand, the support structure 40 comprises stepped portions which are positioned radially outside with respect to the groove 43 and which extend in support planes orthogonal to the X-axis. More precisely, first stepped portions extend in a first support plane orthogonal to the X-axis, second stepped portions extend in a second orthogonal support plane to the X-axis, and third stepped portions extend in a third support plane orthogonal to the X-axis, and the first, second, and third support planes are axially offset. Each of the first, second, and third support planes defines a plane from which the folded portions 53, 63, 73 of one of the connecting wires 50, 60, 70 protrude. In other words, the first stepped portions extend in the first support plane and support the folded portions 53 of the connecting wire 50, the second stepped portions extend in the second support plane and support the folded portions 63 of the connecting wire 60, and the third stepped portions extend in the third support plane and support the folded portions 73 of the connecting wire 70.

[0063] Figures 5 and 6 show a stepped portion 47 that supports a folded portion 73 of the connecting wire 70, it being understood that the description of the stepped portion 47 is also applicable to the stepped portions that support the folded portions 53, 63. The connecting wire 70 has two wire portions 75, each of which connects the folded portion 73 to one of the wire portions 74. The wire portions 75 rest on the stepped portion 47, so that the stepped portion 47 supports the folded portion 73.

[0064] Furthermore, it can be seen in [Fig. 5] and the left-hand view of [Fig. 6] that the stepped portion 47 has a lug 47A which projects axially from the stepped portion 47. As is more clearly visible in the left-hand view of [Fig. 6], the wire portions 75 are located on either side of the lug 47A, such that a stop between one of the wire portions 75 and the lug 47A prevents the connecting wire 70 from rotating about the X-axis. Advantageously, the wire portions 75 extend radially as shown in [Fig. 5] and [Fig. 6], which simplifies the installation of the connecting wire 70.

[0065] When the support structure 40 is made of a polymer material as mentioned above, after installing the connecting wire 70, the lug 47A is advantageously hot-formed to deform the lug 47A as shown in the right-hand view of [Fig. 6]. After cooling, the deformed lug 47A also axially blocks the connecting wire 70, i.e., the deformed lug 47A blocks the connecting wire 70 in translation along the X-axis.

[0066] It should be noted that a lug 47A may be provided on each of the stepped portions 47 or on only some of the stepped portions 47. Similarly, all or some of the stepped portions which support the folded portions 53, 63 may have a lug similar to the lug 47A to lock the connecting wires 50, 60 in rotation around the X axis and advantageously in translation along the X axis.

[0067] Referring back to [Fig. 3] and [Fig. 4], the interconnector 37 further includes a neutral wire 80 which is also supported by the support structure 40. Similar to the connecting wires 50, 60, 70, the neutral wire 80 runs from a neutral point around the X-axis to return to the neutral point, and includes folded portions 83 and portions of wire 84 between the folded portions 83. The ends of the neutral wire 80 may or may not be soldered to each other. More precisely, the neutral wire 80 has 3N folded portions 83 and 3N-1 portions of wire 84, each portion of wire 84 being between two consecutive folded portions 83.

[0068] The folded portions 83 of the neutral wire 80 are arranged alternately with the folded portions 53, 63, 73 of the connecting wires 50, 60, 70. In other words, by traversing the annular shape of the support structure 40 around the X-axis and considering the folded portions 53, 63, 73, 83, one encounters alternately a folded portion 83 of the neutral wire 80 and a folded portion 53, 63, 73. Since the folded portions 53, 63, 73 are arranged periodically around the X-axis as mentioned above, by traversing the annular shape of the support structure 40 around the X-axis and considering the folded portions 53, 63, 73, 83, one successively encounters a folded portion 53, then a folded portion 83, then a folded portion 63, then a folded portion 83, then a folded portion 73, then a folded portion 83, then again a folded portion 53, etc.

[0069] Referring back to [Fig. 5] and [Fig. 6], the support structure 40 comprises fourth stepped portions 48 to support wire portions 85 analogous to wire portions 75, and thus support the folded portions 83 of the neutral wire 80. The fourth stepped portions 48 extend in a fourth support plane orthogonal to the X-axis, where the first, second, third, and fourth support planes are axially offset. The fourth stepped portions 48 are otherwise identical to the stepped portions 47 and are not described in detail again.

[0070] Furthermore, as can be seen in [Fig.5], the wire portions 84 of the neutral wire 80 are axially offset with respect to the wire portions 54, 64, 74. For example, as shown in [Fig.5], the wire portions 84 run along the channel 43 and are axially offset with respect to the wire portions 74 which run along the channel 43.

[0071] All or some of the fourth stepped portions 48 may include a lug 48A, which is analogous to the lugs 47A and can be hot-formed in a manner analogous to the lugs 47A.

[0072] The interconnector 37 can be manufactured as follows. First, the support structure 40 is manufactured, for example by molding or machining. Second, the connecting wires 50, 60, 70 and the neutral wire 80 are made to have the folded portions 53, 63, 73, 83 described above. Then, the connecting wires 50, 60, 70 and the neutral wire 80 are arranged on the support structure 40 in the order dictated by the axial offset of the wire portions 54, 64, 74, 84. For example, in the example shown in [Fig. 5], the connecting wire 50 is arranged first, then the connecting wire 60, then the connecting wire 70, and finally The neutral wire 80. The groove 43 and the lugs 47A, 48A, possibly hot-formed as described above, tend to facilitate the step of arranging the connecting wires 50, 60, 70 and the neutral wire 80 on the support structure 40. Finally, the ends 51 and 52, 61 and 62, 71 and 72 of the connecting wires 50, 60, 70 are inserted into the connectors 95, 96, 97, which completes the manufacture of the interconnector 37. It can therefore be seen that thanks to the described arrangement of the connecting wires 50, 60, 70 and the neutral wire 80, the interconnector 37 can be manufactured in a limited number of simple steps, and therefore at low cost.

[0073] With further reference to [Fig. 5] and [Fig. 6], the support structure 40 advantageously comprises an external rim 41 which is positioned radially outside with respect to the stepped portions, and / or advantageously comprises an internal rim 42 which is positioned radially inside with respect to the groove 43 and forms an internal edge of the groove 43. The external rim 41 and the internal rim 42 further facilitate the step of arranging the connecting wires 50, 60, 70 and the neutral wire 80 on the support structure 40.

[0074] The support structure 40 can be made of a polymer material such as poly(phenylene sulfide) (PPS). The polymer material may also include fillers, such as fibers, for example glass fibers. In the example shown, the support structure 40 is made of the aforementioned polymer material and has through holes 49 (see [Fig. 3], [Fig. 4]) extending axially to attach the support structure 40 to the first half of the housing 9 by means of screws or other fasteners. Advantageously in this case, the support structure 40 further comprises one or more indexing pins 49P (see [Fig.3], [Fig.4]) extending axially to pre-position the support structure 40 relative to the first half-case 9 before bringing the support structure 40 back to the half-case 9. Alternatively, the support structure 40 is made as a single piece with the first half-case 9.

[0075] The connecting wires 50, 60, 70 and the neutral wire 80 are, for example, produced by forming a wire of an appropriate length. Advantageously, the wire is round, which facilitates forming and also results in a very low copper loss rate during manufacturing compared to a process in which flat traces are cut, thus reducing the carbon footprint. More advantageously, the round wire is enameled, the enamel forming an electrically insulating layer on the surface of the connecting wires 50, 60, 70 and the neutral wire 80. Thus, and since, moreover, the axial offset of the wire sections 54, 64, 74, 84 tends to ensure that the connecting wires 50, 60, 70 and the neutral wire 80 do not come into contact with each other, it is not necessary to place electrical insulation on the support structure 40 between the wire sections 54, 64, 74, 84, which further simplifies manufacturing. of the interconnector 37. Of course, such electrical insulation can still be provided if an additional degree of electrical insulation is desired. For example, a suitable resin can be injected into the groove 43 and optionally onto the stepped portions of the support structure 40.

[0076] Of course, if enameled wire is used, it is stripped at the locations provided for the electrical connection of the connecting wires 50, 60, 70 and the neutral wire 80. In particular, the connecting wires 50, 60, 70 are stripped at their end portions 51 and 52, 61 and 62, 71 and 72 to allow the electrical connection with the connectors 95, 96, 97.

[0077] In addition, the connecting wires 50, 60, 70 and the neutral wire 80 are stripped at all or part of the folded portions 53, 63, 73, 83 to allow the electrical connection with the windings 24, which will now be described with reference to [Fig.7].

[0078] For each winding 24, the first terminal end 24P is in contact with a folded portion 53, 63, or 73, and the second terminal end 24N is in contact with a folded portion 83 of the neutral wire 80. Thus, each winding 24 is electrically connected to one of the connecting wires 50, 60, 70 via a folded portion 53, 63, 73 and to the neutral wire 80 via a folded portion 83. Since, on the other hand, the folded portions 53, 63, 73 are arranged periodically around the X-axis, the windings 24 connected to the connecting wires 50, 60, 70 are therefore arranged periodically around the X-axis. In this way, each of the connecting wires 50, 60, 70 can correspond to one of the phases U, V, W of the electrical machine 1 while that the neutral wire 80 corresponds to the neutral of the electrical machine 1.

[0079] Furthermore, thanks to the fact that the folded portions 53, 63, 73, 83 protrude axially from the support structure 40, it is particularly easy to connect the windings 24 of the first stator 16 and the second stator 18 to the connecting wires 50, 60, 70 and to the neutral wire 80, even though the first stator 16 and the second stator 18 are axially offset since they are arranged axially on either side of the rotor 17. It can therefore be seen that thanks to the arrangement of the connecting wires 50, 60, 70 and the neutral wire 80, it is easy to manufacture an axial flux electric machine 1 using a single interconnector for two stators.

[0080] Returning to [Fig. 1], the second half-case 4 has a plurality of windows 4W arranged around the axis X, between the bottom wall 6 and the outer skirt 5, and the folded portions 53, 63, 73, 83 pass through the windows 4W so as to protrude towards the end 8A of the rotor shaft 8. When the case 3 is fixed to a bell of a reduction device as mentioned above, the windows 4W can allow the passage of a cooling fluid used to cool the coils 22 of the stators 16, 18.

[0081] The interconnector 37 shown in the figures is only one particular embodiment. Other arrangements are conceivable, including for manufacturing electrical machines that have a different configuration from the axial flux electrical machine 1 shown in the figures.

[0082] According to some variants, the electric machine 1 has a single stator axially offset with respect to the rotor 17, i.e., one of the first stator 16 and the second stator 18 is omitted. In this case, the folded portions 53, 63, 73 are each in contact with a single first terminal end 24P instead of two first terminal ends 24P as shown in the figures. Similarly, the folded portions 83 are each in contact with a single second terminal end 24N instead of two second terminal ends 24N as shown in the figures.

[0083] According to some variants, the interconnector 37 may only include the connecting wires 50, 60, 70, i.e. the neutral wire 80 is omitted from the interconnector 37. In this case, the folded portions 53, 63, 73 are each in contact with a first terminal end 24P of a winding 24, while the second terminal ends 24N of the windings 24 are in contact with a neutral wire that is not supported by the support structure 40. The second terminal ends 24N and the neutral wire are, for example, positioned radially inside with respect to the teeth 19 of the stators 16, 18.

[0084] According to some variants, the folded portions 53, 63, 73, 83 protrude from the support structure 40 radially, and not axially as shown in the figures.

[0085] Furthermore, according to certain embodiments, the interconnector 37 can also be used to manufacture a radial flux electric machine, that is to say an electric machine in which the stator is positioned radially outside with respect to the stator.

[0086] Although the invention has been described in connection with several particular embodiments, it is clearly evident that it is by no means limited to them and that it includes all technical equivalents of the means described as well as their combinations if these fall within the scope of the invention.

[0087] The use of the verb "comprise", "comprendre" or "include" and its conjugated forms does not exclude the presence of other elements or other steps than those stated in a claim.

[0088] In the claims, any reference sign in parentheses shall not be interpreted as a limitation of the claim.

Claims

1. Demands Interconnector (37) for an electrical machine (1), the interconnector (37) comprising: - a support structure (40) having an annular shape centered around an X-axis and comprising a first connector (95), a second connector (96), and a third connector (97); and - a first connecting wire (50), a second connecting wire (60), and a third connecting wire (70) which are supported by the support structure (40), in which the first connecting wire (50) runs from the first connector (95) around the X-axis to return to the first connector (95), in which the second connecting wire (60) runs from the second connector (96) around the X-axis to return to the second connector (96), in which the third connecting wire (70) runs from the third connector (97) around the X-axis to return to the third connector (97), the first connecting wire (50), the second connecting wire (60), and the third connecting wire (70) each comprising N folded portions (53, 63,73) projecting from the support structure (40), each folded portion (53, 63, 73) being suitable and intended to be connected to a terminal end (24P) of a winding (24) of the electrical machine (1), where N is an integer greater than or equal to 2, the folded portions (53, 63, 73) of the first connecting wire (50), the second connecting wire (60) and the third connecting wire (70) being arranged periodically around the X axis, wherein the first connecting wire (50), the second connecting wire (60) and the third connecting wire (70) each have Nl wire portions (54, 64, 74) between two consecutive folded portions (53, 63, 73), wherein the support structure (40) has a groove (43) and first, second and third stepped portions positioned radially outside with respect to the groove (43) and extending respectively in a first, second and third support planes orthogonal to the X axis, the folded portions (53, 63, 73) being supported by the stepped portions and the wire portions (54, 64, 74) running in the groove (43) or opposite the groove (43), and wherein the first, second and third support planes are axially offset and the Nl wire portions (54) of the first connecting wire (50) are axially offset relative to the Nl wire portions (64) of the second connecting wire (60) and the Nl wire portions (64) of the second connecting wire (60) are axially offset relative to the Nl wire portions (74) of the third connecting wire (70) and wherein at least some of the stepped portions have a lug (47A) arranged to block one of the first connecting wire (50), the second connecting wire (60) and the third connecting wire (70) from rotating about the X axis.

2. Interconnector (37) according to claim 1, wherein the folded portions (53, 63, 73) project axially from the support structure (40).

3. Interconnector (37) according to any one of claims 1 to 2, wherein the first connecting wire (50), the second connecting wire (60) and the third connecting wire (70) are each made by forming a round enameled wire, the round enameled wire being stripped at all or part of the folded portions (53, 63, 73).

4. Interconnector (37) according to claim 1, wherein the support structure (40) is made of a polymer material, and wherein the lugs (47) are hot-formed so as to block the first connecting wire (50), the second connecting wire (60) and the third connecting wire (70) in translation along the X axis.

5. Interconnector (37) according to any one of claims 1 to 4, further comprising a neutral wire (80), the neutral wire having 3N folded portions (83) projecting from the support structure (40) along the X axis, the folded portions (83) of the neutral wire (80) being arranged alternately with the folded portions (53, 63, 73) of the first connecting wire (50), the second connecting wire (60) and the third connecting wire (70) around the X axis.

6. Interconnector (37) according to claim 5, wherein the neutral wire (80) is made by forming a round enamelled wire, the round enamelled wire being stripped at all or part of the folded portions (83).

7. Electrical machine (1) comprising: - a rotor (17) fixed in rotation to a rotor shaft (8), the rotor shaft (8) being movable in rotation about an axis of rotation; - a first stator (16), the first stator (16) comprising a plurality of first coils (22) each having a first winding (24) and which are arranged around the axis of rotation; and - an interconnector (37) for connecting the windings (24) of the first coils (22) to each other and to a power source, wherein: the interconnector (37) is according to any one of claims 1 to 6, the axis X of the support structure (40) of the interconnector (37) is parallel to the axis of rotation, the folded portions (53, 63, 73) of the first connecting wire (50), of the second connecting wire (60) and of the third connecting wire (70) are each connected to a first winding (24) by contact with a first terminal portion (24P) comprising said first winding (24).

8. Electric machine (1) according to claim 7 in which the interconnector (37) is according to any one of claims 5 to 6 and the folded portions (83) of the neutral wire (80) are each connected to one of the first windings (24) by contact with a second terminal portion (24N) comprising said first winding (24).

9. An electric machine (1) according to any one of claims 7 to 8, wherein the electric machine (1) further comprises a second stator (18), the first stator (16) and the second stator (18) being arranged axially on either side of the rotor (17), the second stator (18) having a plurality of second coils (22) each having a second winding (24) and arranged around the axis of rotation, and wherein the folded portions (53, 63, 73) of the first connecting wire (50), the second connecting wire (60) and the third connecting wire (70) are each connected to one of the second windings (24) by contact with a first terminal portion (24P) comprising said second winding (24).

10. An electrical machine (1) according to any one of claims 7 to 9, wherein the electrical machine (1) further comprises a first half-casing (9), the first stator (16) being housed in the first half-casing (9).

11. Electric machine (1) according to claim 10, wherein the support structure (40) of the interconnector (37) is referred to the first half-casing (9).

12. Electric machine (1) according to claim 10, wherein the support structure (40) of the interconnector (37) is formed in one piece with the first half-casing (9).

13. Electric machine (1) according to any one of claims 10 to 12, wherein the electric machine (1) further comprises a second half-casing (4) which is fixed to the first half-casing (9), the second half-casing (4) defining with the first half-casing (9) a housing space in which the first stator (16) and the rotor (17) are housed.

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