Mechanical arrangement with electrical insulation between an electric lathe and its electronic part

Description

[0001] The invention relates in particular to a mechanical assembly with electrical insulation between a rotating electrical machine and its electronic part, in particular for a motor vehicle.

[0002] The invention finds a particularly advantageous application in the field of rotating electrical machines such as alternators, alternator-starters or even reversible machines. It is recalled that a reversible machine is a rotating electrical machine capable of working reversibly, on the one hand, as an electric generator in alternator function and, on the other hand, as an electric motor for example to start the thermal engine of the motor vehicle.

[0003] A rotating electrical machine comprises a machine part and an electronic part. The machine part mainly comprises a movable rotor rotating around an axis of rotation, a fixed stator surrounding the rotor and a casing in which the rotor and stator are mounted. The electronic part mainly comprises a heat sink on which power modules and / or a control module can be mounted. These modules are used to control the excitation of the machine and to transform the alternating current coming out of the stator phases into direct current.

[0004] The electronic part of the rotating electrical machine is mounted on the machine part to simplify the electrical connections of the various modules with the rotor and the stator as well as to save space within the motor vehicle. It is therefore necessary to fix the machine part with the electronic part. Typically, to achieve this assembly, the heat sink of the electronic part and the casing of the machine part each have an openwork portion allowing the passage of a screw.

[0005] For various reasons, the heat sink and the casing may be at different electrical potentials. It is therefore necessary to electrically isolate them from each other. For this, a first insulator is conventionally used, placed between the heat sink and the screw, and a second insulator is placed between the casing and the heat sink, each of the insulators having an opening for the screw to pass through. This results in a stack between metallic materials: the screw, the heat sink and the casing; and plastic materials: the two insulators. This type of stacking has the disadvantage that a large part of the tightening is lost, particularly during the thermal variations experienced by the product throughout its life. Indeed, as the tightening of the screw is significant, it is likely to deform the insulators locally by crushing them, thus creating a matting phenomenon.Furthermore, if the insulators used have a coefficient of expansion greater than that of the conductive parts, then the insulators will undergo significant compressive forces with the variation in temperature and will deform under the effect of creep. These phenomena of matting and creep, as well as the relaxation of plastic materials, lead to a loss of thickness of the insulators and consequently a reduction in the tightening of the assembly between the machine part and the electronic part. This loss of tightening can cause the appearance of play in the assembly, which results in poor resistance of the rotating electrical machine to vibration.

[0006] Documents WO 2015 / 033064 and FR 2807218 describe assembly architectures between the heat sink and the casing of a rotating electrical machine.

[0007] The present invention aims to avoid the drawbacks of the prior art.

[0008] To this end, the present invention therefore relates to a rotating electrical machine for a motor vehicle according to claim 1.

[0009] According to the present invention, the machine comprises: two parts to be assembled formed: of a machine part which comprises a casing and active parts housed in said casing; of an electronic part mounted on the casing, said electronic part being arranged to control the machine part; and at least one assembly device extending along a fixing axis, making it possible to mount the electronic part on the machine part and comprising: a fixing element extending along the fixing axis, a first insulator formed of an electrically insulating material and arranged axially between the fixing element and one of the parts to be assembled, a second insulator formed of an electrically insulating material and arranged axially between the machine part and the electronic part. Still according to the invention, the assembly device further comprises at least one plate arranged in contact with one of the insulators, the plate being formed from a material which has a hardness greater than that of the material of the insulator with which it is in contact.

[0010] The use of a plate reinforces the insulating part which is in contact with said plate and thus allows a better distribution of forces in the insulator which protects it from significant local deformations. This therefore makes it possible to limit the phenomenon of matting corresponding to the crushing of the insulator when tightening the fixing element. A better tightening of said fixing element is therefore possible. This makes it possible to guarantee reliable mounting of the electronic part on the machine part.

[0011] In addition, the use of the plate allows the use of a smaller diameter fixing element without risk of damaging the insulation. This then makes it possible to reduce the mass and size of the assembly device and therefore of the rotating electrical machine.

[0012] According to one embodiment, the hardness of the plate material is at least 60 HB and in particular of the order of 150 HV.

[0013] In one embodiment, the plate is formed from a metallic material. In one embodiment, the insulators are formed from a plastic material. For example, the insulators may be formed from the same material or a different material.

[0014] In one embodiment, the plate is overmolded into the insulator. The plate then forms an insert in the electrically insulating material. Alternatively, the plate can be clipped or glued. As a further alternative, the plate can be attached to the insulator, with the insulator and the plate being held together by the fastening element.

[0015] According to one embodiment, the electronic part comprises at least one electronic module and a heat sink allowing the cooling of the module, the heat sink comprising areas for attachment to the machine part. For example, the electronic part comprises several power modules forming a rectifier bridge and a control module allowing in particular the excitation of the machine to be controlled.

[0016] According to one embodiment, the housing comprises two flanges, one of the flanges having fixing zones with the electronic part. For example, each of the flanges comprises a flat portion extending radially relative to an axis of rotation of the machine, the flat portion carrying at its internal periphery a bearing coupled with a shaft of the machine, and a cylindrical skirt extending axially from an external periphery of the flat portion towards the cylindrical skirt of the other flange.

[0017] According to one embodiment, the plate is separate from the casing and the heat sink.

[0018] According to the invention, a first plate is arranged in contact with the first insulator. Thus, the plate is arranged axially between one of the parts to be assembled and the fixing element. The part to be assembled may be the heat sink or the casing.

[0019] For example, the plate is arranged in contact with the fastening element. In other words, the plate is arranged axially between the first insulator and the fastening element. This makes it possible to improve the non-deformation effect of the first insulator compared to if the plate were in contact with the element to be assembled because the contact surface between the first insulator and the fastening element is smaller than the contact surface between said insulator and the part to be assembled.

[0020] According to the invention, a second plate is arranged in contact with the second insulator. Thus, the plate is arranged axially between the machine part and the electronic part. In this case, the plate is arranged between the heat sink and the housing.

[0021] For example, the plate is arranged in contact with the one between the machine part and the electronic part which has the smallest contact surface with the second insulator.

[0022] According to the invention, the assembly device comprises a first plate arranged in contact with the first insulator and a second plate arranged in contact with the second insulator.

[0023] According to one embodiment, the fixing element comprises a head and a body extending from the head along an assembly axis so as to pass through openings provided at least in the electronic part and the machine part.

[0024] According to one embodiment, the assembly axis extends substantially parallel to the axis of rotation of the machine.

[0025] According to one embodiment, the heat sink and the casing each comprise perforated fixing zones allowing the passage of the fixing element. In this case, the plate and the insulators each comprise an opening for the passage of the body of the fixing element.

[0026] According to one embodiment, the fastening element has a portion which cooperates with the opening of the machine part and in particular that of the casing. For example, the fastening element is a screw or a tie rod. In this case, the fastening element has a threaded portion which cooperates with a tapping of the opening of the casing.

[0027] According to one embodiment, the threaded portion can be covered with a coating, commonly called thread lock, to ensure the fixing between the housing and the fixing element.

[0028] According to one embodiment, the plate has a ring shape. In an alternative embodiment, the plate may comprise several portions forming a ring, the portions being able to be spaced from each other.

[0029] According to one embodiment, the first insulator comprises a body and a sleeve extending projecting from the body so as to at least partially surround the fastening element. In this case, the sleeve is positioned radially between the fastening element and the part to be assembled. The sleeve forms an insulating barrel and contributes to the electrical insulation of the fastening element. For example, the sleeve extends from an internal periphery of the body.

[0030] According to one embodiment, the body of the first insulator extends radially relative to the assembly axis and in particular has a ring shape. In this case, the plate extends in contact with the body.

[0031] According to one embodiment, protrusions project from an external surface of the sleeve towards the part to be assembled. These protrusions allow the first insulator to be held in the part to be assembled.

[0032] According to one embodiment, the first insulator further comprises a collar extending projecting from the body in a direction opposite to that in which the sleeve extends and extending so as to at least partially surround the fixing element. The collar makes it possible to improve the electrical insulation between the fixing element and the part to be assembled with which it is closest by avoiding the formation of salt bridges.

[0033] For example, the collar extends from an outer periphery of the body. For example, the collar extends so as to surround the head of the fastener.

[0034] According to one embodiment, the second insulator comprises a plate-shaped body and fixing zones each formed of a skirt, in particular cylindrical, and a transverse part, in particular perforated for the passage of the fixing element. In this case, the plate extends in contact with the transverse part. For example, the skirt can extend directly from the body or from an arm which extends from the body.

[0035] According to one embodiment, the assembly device further comprises a conical washer arranged axially between the first insulator and the fastening element. Such a conical washer makes it possible to compensate for the deformation of the insulators due to temperature variations during operation of the vehicle. Thus, the washer makes it possible to compensate for the effects of creep and matting of the plastic materials present in the assembly zone and thus to guarantee, over time, minimal tension in the fastening element and therefore good tightening of said element. Thus, the mechanical strength of the fastening between the machine part and the electronic part is improved.

[0036] According to one embodiment, the washer is in contact with the plate and the fixing element.

[0037] According to one embodiment, the washer has an inner portion in contact with the fastening element and an outer portion in contact with the first insulator or the plate. For example, the washer extends in a direction inclined relative to a radial direction.

[0038] According to one embodiment, the washer is formed from a hard material and in particular a metallic material.

[0039] According to one embodiment, the material of the washer and that of the plate are similar materials. This makes it possible to avoid the phenomenon of electro-corrosion also called "battery effect".

[0040] According to one embodiment, the washer has grooves extending in projection towards the plate. This makes it possible to prevent loosening of the screw and thus improve the mechanical strength of the fixing between the machine part and the electronic part. Alternatively, the grooves may extend towards the fixing element and in particular towards the head of said element.

[0041] According to one embodiment, at least one of the assembly devices is arranged on an outer periphery of the rotating electrical machine. In particular, all the assembly devices are arranged on the outer periphery. The assembly devices are thus positioned in more accessible areas, which makes it possible to simplify the fixing of the machine part with the electronic part.

[0042] The assembly devices of the same electrical machine may be different from each other. Each assembly device may comprise one or more embodiments previously described.

[0043] The rotating electrical machine can, advantageously, form an alternator, an alternator-starter or a reversible machine.

[0044] The present invention may be better understood by reading the detailed description which follows, non-limiting examples of implementation of the invention and by examining the appended drawings, in which: there figure 1 represents, schematically and partially, a sectional view, in a plane comprising the axis of rotation, of a rotating electrical machine according to an exemplary implementation of the invention, the figure 2 represents, schematically and partially, a sectional view, in a plane including the assembly axis, of the assembly device of the figure 1 , there figure 3 represents, schematically and partially, a perspective view of an example of insulation of the figure 2 , there figure 4 represents, schematically and partially, a sectional view, in a plane including the assembly axis, of an example of a washer of the figure 2 , there figure 5 represents, schematically and partially, a perspective view from above of an example of a shutter of the figure 2 , there figure 6 represents, schematically and partially, a perspective view from below of the shutter of the figure 5 , and the figure 7 represents, schematically and partially, a top view of the rotating electrical machine of the figure 1 .

[0045] Identical, similar or analogous elements retain the same references from one figure to another.

[0046] The embodiments described below are in no way limiting; in particular, it is possible to imagine variants of the invention comprising only a selection of features described below isolated from the other features described, if this selection of features is sufficient to confer a technical advantage or to differentiate the invention from the prior art. In particular, all the variants and all the embodiments described can be combined with each other if nothing prevents this combination from a technical point of view. In such a case, mention would be made in the present description.

[0047] There figure 1 represents a compact and polyphase rotating electrical machine 10, in particular for a motor vehicle. This rotating electrical machine 10 transforms mechanical energy into electrical energy, in alternator mode, and can operate in motor mode to transform electrical energy into mechanical energy. This rotating electrical machine 10 is, for example, an alternator, an alternator-starter or a reversible machine. The rotating electrical machine comprises a machine part 37 and an electronic part 36.

[0048] The machine part 37 comprises a casing 11. Inside this casing 11, it further comprises a shaft 13, a rotor 12 integral in rotation with the shaft 13 and a stator 15 surrounding the rotor 12. The rotational movement of the rotor 12 takes place around an axis of rotation X.

[0049] In the remainder of the description, the terms front and rear refer to the axis of rotation X passing through the shaft 13 in its center. The front portion corresponds to an element oriented towards the front part of the shaft 13 and therefore towards the pulley or closer to the pulley compared to a second element, the rear term designating a distance from the pulley.

[0050] In this example, the casing 11 comprises a front flange 16 and a rear flange 17 which are assembled together. These flanges 16, 17 are hollow in shape and each centrally carry a bearing coupled to a respective ball bearing 18, 19 for the rotational mounting of the shaft 13. In addition, the casing 11 comprises fixing means 14 allowing the mounting of the rotating electrical machine 10 in the vehicle.

[0051] Each flange 16, 17 comprises a flat portion extending radially relative to the axis of rotation X and a cylindrical skirt extending projecting from an external periphery of the flat portion towards the cylindrical skirt of the other flange.

[0052] A pulley 20 is fixed on a front end of the shaft 13, at the level of the front flange 16, for example using a nut resting on the bottom of the cavity of this pulley. This pulley 20 makes it possible to transmit the rotational movement to the shaft 13 or for the shaft 13 to transmit its rotational movement to the belt.

[0053] The rear end of the shaft 13 carries, here, collector rings 21 belonging to a collector 22. Brushes 23 belonging to a brush holder 24 are arranged so as to rub on the collector rings 21. The brush holder 24 is connected to a voltage regulator (not shown).

[0054] The front flange 16 and the rear flange 17 may further comprise substantially lateral openings for the passage of air in order to allow the rotating electrical machine to be cooled by air circulation generated by the rotation of a front fan 25 on the front face of the rotor 12, i.e. at the level of the front flange 16 and of a rear fan 26 on the rear face of the rotor, i.e. at the level of the rear flange 17.

[0055] In this example, the rotor 12 is a claw rotor. It comprises two pole wheels 31. Each pole wheel 31 is formed of a plate 32 and a plurality of claws 33 forming magnetic poles. The plate 32 is transversely oriented relative to the axis of rotation X and has, for example, a substantially annular shape. This rotor 12 further comprises a cylindrical core 34 which is interposed between the pole wheels 31. Here, this core 34 is formed of two half-cores each belonging to one of the pole wheels. The rotor 12 comprises, between the core 34 and the claws 33, a coil 35 comprising, here, a winding hub and an electrical winding on this hub. For example, the collector rings 21 belonging to the collector 22 are connected by wire connections to said coil 35. The rotor 12 may also comprise magnetic elements interposed between two adjacent claws 33.

[0056] In this embodiment, the stator 15 comprises a body 27 in the form of a stack of sheets provided with notches, for example of the semi-closed or open type, equipped with notch insulation for mounting an electric winding 28. This winding 28 passes through the notches of the body 27 and forms a front bun 29 and a rear bun 30 on either side of the stator body. The winding 28 is connected, for example, in a star or even a delta.

[0057] Furthermore, the winding 28 is formed of one or more phases. Each phase comprises at least one conductor passing through the notches of the stator body 27 and forms, with all the phases, the buns. The winding 28 is electrically connected to an electronic assembly 36.

[0058] The electronic part 36 comprises at least one electronic power module for controlling a phase of the winding 28 and a control module for controlling the excitation of the rotor. The power module forms a voltage rectifier bridge for transforming the alternating voltage generated by the alternator 10 into a direct voltage for supplying in particular the battery and the on-board network of the vehicle in alternator mode. The electronic part further comprises a heat sink 38 for cooling at least one of the modules. For example, the power modules are mounted on the heat sink.

[0059] When the electrical winding is electrically powered from the brushes, the rotor 12 is magnetized and becomes an inductor rotor with the formation of North-South magnetic poles at the claws 33. This inductor rotor creates an alternating induced current in the stator when the shaft 13 is rotating. The rectifier bridge then transforms this alternating induced current into a direct current, in particular to supply the loads and consumers of the on-board network of the motor vehicle as well as to recharge its battery.

[0060] The electronic part 36 is mounted on the machine part. In particular in the embodiment described in the figure 1 , the heat sink 38 of the electronic part 36 is mounted on the casing 11 of the machine part 37 and in particular on the rear flange 17. To achieve this assembly, the heat sink 38 and the casing 11 each comprise fixing zones respectively facing each other. In particular in this example, the rear flange 17 comprises several pads each extending in projection towards the electronic part and forming a fixing zone.

[0061] Each assembly zone comprises an assembly device 39. The assembly device comprises a fixing element 40 extending along an assembly axis Y, a first insulator 41, a second insulator 42 and two plates 43, 53.

[0062] In the remainder of the description, the axial, radial, external and internal designations refer to the assembly axis Y passing through the center of the fixing element 40. The axial direction corresponds to the Y axis while the radial orientations correspond to planes that are concurrent, and in particular perpendicular, to the Y axis. For the radial directions, the external or internal designations are assessed in relation to the same Y axis, the internal designation corresponding to an element oriented towards the axis, or closer to the axis compared to a second element, the external designation designating a distance from the axis. In the example of the figure 1 , the assembly axis Y extends substantially parallel to the rotation axis X of the rotating electrical machine 10. Throughout the description and in the claims, the term "substantially parallel" means an angle between 0° and 20°.

[0063] In the example of the figure 2 , the fastening element 40 comprises a head 44 and a body 45 extending from the head along the assembly axis Y. In this example, the fastening element 40 is a screw. In a variant, this element could be a tie rod or any other suitable fastening means.

[0064] The heat sink 38, the rear flange 17, the first plate 43 and the insulators 41, 42 each comprise an opening allowing the passage of the fixing element 40. In this exemplary embodiment, the fixing element 40 is inserted into the heat sink 38 then into the casing 11. Thus, the head 44 of said element is positioned axially on the side of the heat sink and the body 45 of said fixing element has a portion which cooperates with the opening of the casing 11 to ensure the fixing of the two elements. In this case, the body 45 has a threaded portion which cooperates with a tapping of the opening of the casing 11. The threaded portion may be covered with a coating, commonly called thread lock, acting as glue to ensure fixing.

[0065] The heat sink 38 and the rear flange 17 are each formed from an electrically conductive material such as aluminum. These two elements are not necessarily at the same electrical potential, it is therefore necessary to electrically isolate them. For example, the casing 11 is at a chassis ground potential or 12V and the heat sink is at a ground potential of the electrical network with which the machine 10 operates, which is in particular a 48V electrical network. In addition, the fixing element is for example formed from steel which is also an electrically conductive material that must be insulated.

[0066] In the example of the figures 2 et 3 , the first insulator 41 has a body 46 extending radially relative to the assembly axis Y and having in particular a ring shape for the passage of the fixing element 40. The body 46 is arranged axially between the fixing element 40 and the heat sink 38.

[0067] Still in this example, the first insulator 41 comprises a sleeve 47 extending projecting from the body 46 in a direction substantially parallel to the body 45 of the fixing element 40. The sleeve 47 has a cylinder shape surrounding the body 45. The sleeve extends radially between the body 45 and the heat sink 38 and extends from an inner periphery of the body 46 of the insulator. It will be understood that the axial height of the sleeve 47 depends on the length of the heat sink 38 to be insulated.

[0068] As clearly visible on the figure 3 , the first insulator 41 comprises protrusions 48 extending projecting from an external surface of the sleeve towards the heat sink 38. These protrusions 48 may extend axially over the entire length of the sleeve 47. For example, the first insulator 41 comprises three protrusions 48 spaced substantially regularly on the periphery of the sleeve 47, in particular spaced 120° from each other. For example, each protrusion may have a rectangular section or a triangular section as illustrated in the figure 3 .

[0069] Still in this example, the first insulator 41 comprises a collar 49 extending projecting from the body 46 of the insulator 41 in a direction opposite to the direction in which the sleeve 47 extends. For example, the collar extends in a substantially axial direction so as to at least partially surround the fixing element 40 and in particular the head 44 of said element. For example, the collar extends from an external periphery of the body 46. It will be understood that the height of the collar depends on the dimensions of the head 44.

[0070] In the example of the figures 2 , 5 And 6, the second insulator 42 is arranged axially between the machine part 37 and the electronic part 36, that is to say between the heat sink 38 and the rear flange 17. The second insulator 42 comprises a plate-shaped body 50 and fixing zones which are each formed of a skirt 51 and a transverse part 52. The skirt 51 has, here, a cylindrical shape, in particular of revolution, and extends projecting from the body in an axial direction. The transverse portion 52 extends from the skirt in a substantially radial direction and is, here, perforated for the passage of the fixing element 40. For example, the skirt 51 can extend directly from the body 50 but it could also extend from an arm which would extend from the body 50. The skirt 51 and the transverse portion 52 cover the studs extending from the rear flange 17 to form the fixing zones.

[0071] The first insulator 41 and the second insulator 42 are both formed from an electrically insulating material. For example, these insulators are formed from a plastic material, in particular a thermoplastic or thermosetting material such as PEEK. The insulators may be formed from the same material or each from a different material.

[0072] As seen in the example of the figure 2 , the assembly device 39 comprises a first plate 43 and a second plate 53. The first plate is arranged in contact with the first insulator 41 and the second plate 53 is arranged in contact with the second insulator 42.

[0073] The first plate 43 is formed from a material which has a hardness greater than the hardness of the material forming the first insulator 41. In addition, the second plate 53 is formed from a material which has a hardness greater than the hardness of the material forming the second insulator 42. For example, the hardness of the material of the plate is at least 60 HB, in the context of a measurement with the Brinell scale, and in particular of the order of 150 HV, in the context of a Vickers type measurement.

[0074] For example, plates are made of a metallic material such as steel or aluminum. They can be made of the same material or different materials.

[0075] For example, each plate 43, 53 is overmolded in the insulator 41, 42 with which it is in contact.

[0076] In the example shown here, each plate 43, 53 has a ring shape having an opening for the passage of the fixing element 40. Each plate has, here, a cylindrical shape but any other shape can be envisaged.

[0077] The first plate 43 is arranged axially between the heat sink 38 and the fixing element 40 and in particular between the first insulator 41 and said element 40. The plate 43 is overmolded in the body 46 of the first insulator 41.

[0078] The second plate 53 is arranged axially between the heat sink 38 and the rear flange 17 and in particular between the second insulator 42 and the rear flange 17. The plate 43 is overmolded in the transverse portion 52 of the second insulator 42.

[0079] In the example illustrated on the figures 2 And 4, the assembly device 39 further comprises a conical washer 54 arranged axially between the first insulator 41 and the fixing element 40 and in particular between the first plate 43 and said element 40. The washer 54 has an internal portion 55 in contact with the fixing element 40 and an external portion 56 in contact with the first plate 43. For example, the washer 54 is a Belleville washer.

[0080] For example, the washer extends in a direction inclined relative to a radial direction and centrally has an opening for the passage of the fastening element 40. Such a washer has an elastic effect, that is to say that when tightening the fastening element 40 for fastening, it is in a stressed state in which the inner portion 55 and the outer portion 56 can be substantially aligned in a radial direction relative to the assembly axis Y. Then, with the wear of the machine mainly due to the creep of the insulators 41, 42, the washer 54 is in a compensation state in which the inner portion 55 and the outer portion 56 are no longer aligned in the radial direction.

[0081] It will be understood that the dimensions of the washer depend mainly on the desired tightening, the dimensions and materials forming the insulators 41, 42, the dimensions of the fixing element 40 and the plate 43, 53 as well as their respective dimensions and materials. For example, the washer may have an external diameter D2 of between 7 mm and 15 mm, an internal diameter D1 of between 3 mm and 5 mm, a thickness E in an axial direction of the order of 0.8 mm and an axial useful stroke of between 0 mm and 1 mm for a force range of 500 N to 5000 N, the useful stroke being the difference in axial height between the internal portion and the external portion of the washer between the stressed state and the maximum compensation state.

[0082] The washer 54 is formed of a hard material, particularly metallic. For example, the washer is made of steel.

[0083] In an exemplary embodiment not shown, the washer may have grooves extending in projection towards the plate and / or towards the head 44 of the fixing element 40.

[0084] As shown in the figure 7 , all the assembly devices 39 are arranged on an outer circumference of the rotating electrical machine 10. The machine 10 comprises, here, six assembly devices 39 which are distributed angularly along the circumference of the machine. The assembly devices of the same electrical machine may be different from each other. Each assembly device may comprise one or more embodiments previously described.

[0085] Furthermore, as clearly visible on the figure 1, the rotating electrical machine 10 comprises a cover 57 in particular formed of a plastic material making it possible to protect the electronic part 36. For example, this cover 57 is fixed to the machine by studs 58 arranged respectively on certain heads 44 of the fixing elements 40.

[0086] The present invention finds applications in particular in the field of alternators or reversible machines for motor vehicles but it could also be applied to any type of rotating machine.

[0087] Of course, the preceding description has been given by way of example only and does not limit the scope of the present invention, which would not be departed from by replacing the various elements with any other equivalents.

[0088] For example, it will not be outside the scope of the invention to use only one of the two plates 41, 43. Similarly, it will not be outside the scope of the invention to position the assembly device 39 so that the assembly axis Y is substantially orthogonal to the rotation axis X of the machine 10. Similarly, it will not be outside the scope of the invention to insert the fixing element first into the rear flange 17 and then into the heat sink 38 so that the head 44 of said element 40 is closer to the flange than to the heat sink.

Claims

1. Rotating electrical machine for a motor vehicle, said machine (10) comprising: - two parts to be assembled, formed by: - a machine part (37) comprising a casing (11) and active parts (12, 15) housed in said casing; - an electronic part (36) mounted on the casing (11), said electronic part being arranged to control the machine part (37); and - at least one assembly device (39) extending along a fixing axis (Y), allowing the electronic part to be mounted on the machine part and comprising: - a fixing element (40) extending along the fixing axis (Y), - a first insulator (41) made of an electrically insulating material and disposed axially between the fixing element (40) and the electronic part (36), - a second insulator (42) made of an electrically insulating material and disposed axially between the machine part (37) and the electronic part (36), the assembly device (39) further comprising a first plate (43) disposed in contact with the first insulator (41) and disposed axially between said first insulator (41) and the fastening element (40) and a second plate (53) disposed in contact with the second insulator (42), the plates each being made of a material which has a hardness greater than that of the insulating material with which it is in contact.

2. Machine according to claim 1, characterised in that the hardness of the material of at least one of the plates (43, 53) is at least 60 HB and in particular in the order of 150 HV.

3. Machine according to claim 1 or 2, characterised in that at least one of the plates (43, 53) is made of a metallic material.

4. Machine according to any of claims 1 to 3, characterised in that at least one of the plates (43, 53) is moulded into the insulator (41, 42).

5. Machine according to any of claims 1 to 4, characterised in that the first insulator (41) comprises a body (46) and a sleeve (47) extending protruding from the body (46) so as to at least partially surround the fastening element (40).

6. Machine according to claim 5, characterised in that protrusions (48) extend from an outer surface of the sleeve (47) towards the part to be assembled (36, 37).

7. Machine according to claim 5 or 6, characterised in that the first insulator (41) further comprises a flange (49) projecting from the body (46) in a direction opposite to that in which the sleeve (47) extends and extending so as to at least partially surround the fastening element (40).

8. Machine according to any of claims 1 to 7, characterised in that the second plate (53) is arranged in contact with that between the machine part (37) and the electronic part (36) which has the smallest contact surface with the second insulator (42).

9. Machine according to any of claims 1 to 8, characterised in that the assembly device (39) further comprises a conical washer (54) arranged axially between the first insulator (41) and the fastening element (40).

10. Machine according to claim 9, characterised in that the washer (54) is in contact with the plate (43) and the fastening element (40).

11. Machine according to any of claims 1 to 10, characterised in that the electronic part (36) comprises at least one electronic module and a heat sink (38) for cooling the module, the heat sink comprising fastening areas with the machine part (37) and in that the housing (11) comprises two flanges (16, 17), one of the flanges having fastening areas with the electronic part (36).