EP3304696A1

EP3304696A1 - Rotating electrical machine equipped with a device for retaining a system for guiding the rotation of a shaft

Info

Publication number: EP3304696A1
Application number: EP16729318.2A
Authority: EP
Inventors: Patrice BALTHAZE; Henri DELIANNE; Pierre-Yves Bilteryst; David MARGUERITTE; Michel BOCQUEL; Eric JOZEFOWIEZ; Sylvain PERREAUT
Original assignee: Valeo Equipements Electriques Moteur SAS
Current assignee: Valeo Equipements Electriques Moteur SAS
Priority date: 2015-05-27
Filing date: 2016-05-25
Publication date: 2018-04-11
Also published as: WO2016189246A1

Abstract

The invention relates principally to a rotating electrical machine comprising a stator (16) and a rotor (12) mounted on a shaft (13), characterised in that: the rotating electrical machine also comprises a cradle (11) having a bearing surface (20) for the stator (16) and at least one surface (21) for guiding the rotation of the shaft (13); the shaft (13) is mounted on the guiding surface (21) by means of a rotation guiding system (22); and the rotating electrical machine also comprises at least one retaining device (23) for retaining the rotation guiding system (22), said retaining device (23) comprising a clamp (131).

Description

ROTATING ELECTRIC MACHINE HAVING A DEVICE FOR MAINTAINING A ROTATION GUIDE SYSTEM OF A TREE

The present invention relates to a rotating electrical machine provided with a device for maintaining a system for guiding a tree in rotation. The invention finds a particularly advantageous, but not exclusive, application in the field of alternators for a motor vehicle. Such an alternator transforms mechanical energy into electrical energy and can be reversible. Such a reversible alternator is called an alternator-starter and makes it possible to convert electrical energy into mechanical energy, in particular to start the engine of the vehicle. The invention may also be implemented with an electric type motor.

In a manner known per se, an alternator as described in document EP0762617 comprises a housing and, inside thereof, a claw rotor, fixed in rotation directly or indirectly to a shaft, and a stator which surrounds the rotor with the presence of a gap. A pulley is attached to the front end of the shaft.

The stator comprises a body in the form of a pack of sheets with notches equipped with notch insulation for mounting the stator winding. The coil comprises a plurality of phase windings passing through the notches of the body and forming, with all the phase windings, a front bun and a rear bun on either side of the stator body. The windings are obtained for example from a continuous wire covered with enamel or from bar-like conductor elements, such as U-shaped pins whose ends are interconnected for example by welding.

These phase windings are, for example, three-phase windings connected in a star or in a triangle, the outputs of which are connected to at least one electronic rectification module comprising rectifying elements such as diodes or transistors of the MOSFET type, in particular when is an alternator-starter.

In addition, the rotor has two pole wheels. Each wheel has a flange of transverse orientation provided at its outer periphery with teeth for example of trapezoidal shape and axial orientation. The teeth of a wheel are directed axially towards the flange of the other wheel, the tooth of a polar wheel penetrating into the space between two teeth adjacent to the other polar wheel, so that the teeth of the pole wheels are interlocked, some by compared to others. A cylindrical core is interposed axially between the flanges of the wheels. This core carries at its outer periphery an excitation coil wound in an insulator radially interposed between the core and this coil.

In addition, the housing has front and rear bearings assembled together. The rear bearing carries the brush holder, the voltage regulator and at least one bridge rectifier. The bearings are hollow in shape and each carries a ball bearing centrally for rotational mounting of the rotor shaft.

More specifically, the gap is defined as the difference between the inner and outer radius of a hollow cylinder extending between the rotor and the stator of the electric machine. One of the main goals of an electric machine manufacturer is to minimize the air gap, which results in less magnetic noise and increased performance. However, manufacturing tolerances must be taken into account to ensure that the rotor does not interfere with the stator during its rotation, which could destroy the machine.

The current assembly is performed by assembling the two bearings around the package of sheets. This assembly implies a respect of dimensional constraints and geometric constraints related in particular to the coaxiality of the different elements. Thus, from a dimensional point of view, it defines a gap large enough to absorb the rib variations of the machine.

Moreover, from a geometrical point of view, it is necessary to have four diameters with a single axis in order to guarantee the coaxiality of the electric machine, namely the bearing surface of the front bearing, the part of the front bearing receiving the stator, the bearing of the rear bearing, and the part of the rear bearing receiving the stator.

In addition, the assembly is carried out not on the outer diameter of the stator plate package but on the two axial ends of the sheet package, so that it is necessary that it is the perpendiculars to the two parts of the bearing receiving the stator which must define a diameter with said single axis. Mounting on the perpendicular face of the stator therefore generates an additional problem of coaxiality due to the lack of perpendicularity between the axial face of the stator and the outer diameter of the stator. Finally, it also remains to maintain a coaxiality between the outer diameter of the rotor and the internal diameter of the stator.

The invention aims to improve the configuration of existing electrical machines by proposing a rotating electrical machine, comprising a stator and a rotor mounted on a shaft, characterized in that said rotating electrical machine further comprises a cradle having a bearing surface of the stator and at least one rotational guiding surface of said shaft, in that said shaft is mounted on the guide surface via a rotation guiding system, and in that said rotating electrical machine further comprises at least one holding device of said rotation guiding system, said holding device comprising a clam.

The invention thus makes it possible to improve the coaxiality between the shaft and the cradle, which makes it possible to reduce the air gap of the machine because of the reduction in mounting clearance. In addition, the invention makes it possible to facilitate the adaptation of the machine to different types of shafts by using an additional part so that it is possible to adapt the configuration by modifying only the shape of the retaining device of the system. rotation guidance.

According to one embodiment, said cradle comprises two rotational guiding spans of said shaft of said rotor positioned axially respectively on either side of said stator bearing surface.

According to one embodiment, said cradle defines an open volume, such that the stator assembly, shaft and rotor can be respectively deposited in abutment on said bearing surface and said guide surfaces in a mounting direction perpendicular to an axis of the cradle.

According to one embodiment, said rotational guiding system comprises a bearing. In one embodiment, said holding device is configured to hold tight an outer cage of said bearing between said guide surface and said holding device.

According to one embodiment, an axial width of said holding device is substantially equal to an axial width of an outer race of the bearing.

According to one embodiment, said device for holding the rotational guidance system is attached relative to said cradle.

According to one embodiment, said holding device comprises a tag.

According to one embodiment, said slam comprises a bridge extending between two ends fixed on said cradle.

According to one embodiment, while the stator rests on said bearing surface, an axis of said stator coincides with an axis of the cradle, an axis of the rotor, and an axis of an inner periphery of said bridge.

According to one embodiment, said bridge is delimited at its inner periphery and its outer periphery by concentric circles.

According to one embodiment, a ratio between a thickness of said bridge with respect to an internal diameter of said bridge is between 0.05 and 0.3.

According to one embodiment, said rotation guiding system comprising a bearing having an inner ring, a thickness of said bridge is between 0.2 and 3 times the thickness of said inner ring of the bearing. Thus, the clam is sized to support the efforts of the application because the thickness of the inner ring is directly related to these efforts.

According to one embodiment, said device for maintaining the rotational guidance system has a lower height relative to a fan. Thus, the retaining bar does not interfere with the air flow generated by the corresponding fan mounted on an end face of the rotor.

According to one embodiment, said rotating electrical machine comprises means for indexing said holding device relative to the cradle. According to one embodiment, said rotating electrical machine comprises at least one stop system intended to ensure axial retention of the rotational guiding system.

According to one embodiment, said stop system comprises a stop ring formed in the holding device against which is supported said rotation guiding system.

According to one embodiment, said holding device comprises a heat sink comprising fins.

According to one embodiment, said heat sink is attached relative to said holding device of the rotation guide system.

According to one embodiment, said heat sink comes from material with said device for holding the rotating guide system.

In one embodiment, the cradle includes a heat sink of the rotational guiding system. According to one embodiment, the guide surfaces comprise a face receiving the rotation guide system and an opposite face having cooling fins.

The invention will be better understood on reading the description which follows and on examining the figures which accompany it. These figures are given for illustrative but not limiting of the invention.

Figure 1 shows an exploded perspective view of an alternator according to the present invention without the protective cover;

Figure 2 shows an exploded perspective view of an alternator according to the present invention with the protective cover; Figure 3 shows a perspective view of an alternator according to the present illustrating the flow of air flow inside the electric machine;

Figure 4a is a longitudinal sectional view of an alternator according to the present invention in which the stator has a configuration "buried" relative to the bottom of the cradle; Figure 4b is a longitudinal sectional view of an alternator according to the present invention in which the stator has a configuration "raised" relative to the bottom of the cradle;

Figure 5 shows a front view of the stator of the alternator according to the present invention provided with an optimized depth of notch;

Figure 6 is a perspective view of the cradle of the electric machine according to the present invention;

Figure 7 is a perspective view of the cradle of Figure 6 in which a stator has been inserted; Figures 8a to 8d are perspective views illustrating different possible configurations of the stator bearing areas;

Figure 9a is a side view of the cradle of the alternator according to the present invention provided with cooling fins;

Fig. 9b is a side view of the alternator cradle according to the present invention showing the areas in which the cooling fins may be integrated;

Figures 10a and 10b are respectively bottom and side views of a cradle according to the present invention provided with reference pads for locating the part during a machining phase; Figures 11a to 11d are perspective views of the bottom of the cradle illustrating different configurations of the damping elements of the stator;

Figures 12a to 12d are perspective views of the bottom of the cradle illustrating different configurations of recesses provided for the integration of damping elements of the stator; Figure 13 is a top view of a cradle according to the present invention provided with stops for the ball bearings implanted in the bearing guideways in rotation of the shaft; Fig. 14 is a front view of a stator of the alternator according to the present invention provided with an eccentricity with respect to its inside diameter to allow adjustment of the stator axis with respect to the axis of the rotor;

Figure 15 is a front view of a stator retaining tab of the alternator according to the present invention;

Figure 16 is a top view of a stator retaining clam belonging to the alternator according to the present invention;

Figures 17a and 17b are perspective views illustrating the implementation of indexing means of the stator holding tab relative to the cradle;

FIG. 18 is a bottom perspective view of the alternator stator holding tab according to the present invention provided with an indexing stud with respect to the cradle;

Fig. 19 is a perspective view of a stator holding bar according to the present invention provided with a groove for indexing the stator body in position;

Figure 20a is a side view of a stator holding clam according to the present invention provided with cooling fins at the outer periphery;

Figure 20b is a detailed perspective view of the shape of the vanes of the stator holding clamp of Figure 20a;

Figure 21 is a perspective view of a stator retaining clam according to the present invention incorporating a cooling circuit;

Figure 22 is a top view of a stator holding member according to the present invention having two side-by-side keys; Figure 23 is a side view of an alternator according to the present invention provided with a stator holding clam rotatably mounted relative to the cradle via a hinge;

FIGS. 24a and 24b show perspective views of a stator holding bar according to the present invention illustrating different damping element implantation configuration providing an anti-vibration function;

FIGS. 25a to 25c are side views of various embodiments of a stator holding clam according to the present invention for performing a function of anti-vibration and axial retention of the stator;

Figures 26a and 26b illustrate a first mode of attachment to the cradle of a stator provided with excrescences according to the present invention;

FIG. 27 illustrates a second mode of attachment to the cradle of a stator provided with protrusions according to the present invention;

Figure 28 illustrates a third mode of attachment to the cradle of a stator provided with growths according to the present invention;

FIG. 29 illustrates a fourth mode of attachment on the cradle of a stator provided with protrusions according to the present invention; Figure 30 is a perspective view of a stator body according to the present invention provided with a protrusion for indexing with respect to the cradle and / or the stator holding tab;

Figures 31a and 31b are respectively perspective and front views of a bearing holding device according to the present invention; Figure 32 is a perspective view of the bearing holder mounted on the side wall of the cradle shown partially;

Figure 33 is a front view of the bearing holder incorporating indexing means relative to the cradle of the alternator according to the present invention; Figure 34 is a sectional view of the bearing holder according to the present invention incorporating a rolling stop system;

Figure 35 is a partial sectional view of a bearing used with the holding device of Figure 34 in which is formed a groove; Figures 36a and 36b are respectively perspective and side views of a bearing holding device provided with cooling fins at the outer periphery;

Figures 37a to 37c are side views of the bearing holder according to the present invention illustrating alternative embodiments of the cooling fins;

Fig. 38 is a perspective view of the alternator protective cover according to the present invention;

Figure 39 is a perspective view of the alternator according to the present invention provided with an electronic rectification module remote radially on the stator holding tab;

FIGS. 40a and 40b are cross-sectional views illustrating the different possible positions of the phase outputs of the winding of a stator used in the alternator according to the present invention; Fig. 41 is a side view of an alternator according to the present invention showing the positioning of the brush holders;

Figure 42 is a perspective view of an exemplary embodiment of a fan to be fixed against an end face of the rotor;

Figures 43a and 43b are perspective views illustrating alternative embodiments of the alternator provided with a cover respectively comprising a single or two air inlets.

Identical, similar or similar elements retain the same reference from one figure to another.

FIGS. 1, 2, 3, 4a and 4b show a compact and polyphase alternator 10 according to the present invention, in particular for a motor vehicle. This alternator 10 transforms mechanical energy into electrical energy and can be reversible. Such a reversible alternator 10 is called an alternator-starter and makes it possible to transform electrical energy into mechanical energy, in particular for starting the engine of the vehicle. This alternator 10 includes a cradle January 1 and a rotor 12 with claws, integral in rotation directly or indirectly a shaft 13. In addition, a stator 16 surrounds the rotor 12 with the presence of an air gap 17 visible in the figures 4a and 4b. The axis X1 of the shaft 13 forms the axis of rotation of the rotor 12. The shaft 13 carries at one of its ends a pulley 14 belonging to a device for transmitting motion to at least one belt between the alternator 10 and the engine of the motor vehicle.

In this case, the cradle 1 1 X2 axis has a bearing surface 20 of the stator 16 on which rests at least in part the stator 16 and at least two bearing surfaces 21 in rotation of the shaft 13 of the rotor 12 respectively positioned axially on each side of the bearing surface 20 of the stator 16. The shaft 13 is mounted on each guide surface 21 via a bearing 22, so that the shaft 13 is rotatably mounted relative to the cradle 1 1. Bearing retaining devices 23 are provided to hold the bearings 22 in position on the guide surfaces 21 in rotation with the shaft 21. Alternatively, the bearings 22 may be replaced by plain bearings, so that each element 22 may be considered more generally as a system for guiding the shaft 13 in rotation.

In addition, a holding member 26 of the stator 16 is configured to keep a yoke 35 of the stator 16 clamped between the bearing surface 20 of the stator 16 and the holding member 26. The cradle January 1 is closed by a protective cover 30 of complementary shape described in more detail below.

More precisely, as can be seen in FIG. 5, the stator 16 with axis X3 comprises a body 31 having an annular cylindrical shape of axis X3 and consists of an axial stack of plane sheets. The body 31 has teeth 34 distributed angularly in a regular manner on an inner periphery of the yoke 35. These teeth 34 delimit two by two notches 36. The yoke 35 corresponds to the full outer annular portion of the body 31 which extends between the bottom of the notches 36 and the outer periphery of the stator 16.

The notches 36 open axially into the lower and upper axial end faces of the body 31. The notches 36 are also open radially in the internal cylindrical face of the body 31. The stator 16 is preferably provided with a toothed base 37 on the side of the free ends of the teeth 34 to ensure at least a partial closure of the notches.

In addition, a winding 40 clearly visible in Figures 1, 4a and 4b comprises a plurality of phase windings through the notches 36 of the body 31 of the stator 16 and forming, with all phases, a front bun 41 a and a bun rear 41b on either side of the body 31 of the stator 16. In the following description, it is considered that a "front" element is rotated on the side of the pulley 14 and a "rear" element is rotated on the opposite side.

For example, a 16 "hexaphase stator has six phase windings. The invention is however applicable to stators 16 comprising a different number of phase windings, and in particular to "three-phase" stators comprising three phase windings, or five-phase stators comprising five phase or heptaphased windings comprising seven phase windings. . The number of slots 36 of the stator 16 is preferably adapted as a function of the number of phase windings of the electric machine 10.

The windings are obtained for example from a continuous wire covered with enamel or from bar-like conductor elements, such as U-shaped pins whose ends are interconnected for example by welding. These windings are, for example, star-connected or delta-connected windings whose outputs are connected to an electronic rectification module 46 (see FIG. 39) described in more detail below. The rectifier electronic module 46 comprises rectifying elements 47, such as diodes or transistors of the MOSFET type, in particular when it is an alternator-starter.

The use of the holding member 26 eliminates the mechanical function of the yoke 35 and therefore the associated constraints. The cylinder head 35 can then be sized to optimize the electromagnetic performance of the machine. In particular, the invention makes it possible to increase the depth Pe of the notches 36 in order to increase the filling rate of the notches 36 of the stator 16 in conductors and thus the current delivered by the machine. It will be recalled here that the depth Pe of each notch 36 is defined between the inner periphery of the stator 16 on the rotor side 12 and the notch bottom. The thickness Ec of the cylinder head 35, defined as the radial distance between the bottom of the notch and the outer periphery of the stator 16, may also be reduced if necessary to optimize the overall size of the assembly. Alternatively, with a constant notch surface, it will be possible to increase the orthoradial width of the teeth 34 so as to allow a higher flow rate.

In addition, the alternator 10 is configured such that the magnetic flux raised by the teeth 34 of each phase can pass through the yoke 35 without magnetic saturation. For this purpose, the teeth 34 each have a tooth width A, said thickness Ec of the yoke 35 is greater than or equal to K ^* A, with K corresponding to the number of phases of the electric machine. In the case where the notches 36 have parallel edges, the thickness Ec of the yoke 35 considered is measured at a tooth root 37, that is to say at the place where the tooth width A is the weakest.

Moreover, as can be seen in FIGS. 4a and 4b, the rotor 12 comprises two pole wheels 54. Each wheel 54 has a transversely oriented flange 55 provided at its outer periphery with teeth 56, for example of trapezoidal shape, and axial orientation. The teeth 56 of one wheel 54 are directed axially towards the flange 55 of the other wheel 54, the tooth 56 of a pole wheel 54 penetrating into the space between two teeth 56 adjacent to the other pole wheel 54, so that the teeth 56 of the pole wheels 54 are interleaved. The outer periphery of the teeth 56 is axially oriented and defines with the inner periphery of the body 31 of the stator 16 the gap 17 between the stator 16 and the rotor 12. The inner periphery of the teeth 56 is inclined. These teeth 56 are less thick at their free end. The flanges 55 of the wheels 54 are annular. A cylindrical core 57 is interposed axially between the flanges 55 of the wheels 54.

This core 57 carries at its outer periphery an excitation coil 58 wound in an insulator inserted radially between the core 57 and this coil 58. In the example described, this insulator is made of electrically insulating and moldable material, such as material plastic, while the pole wheels 54 and the core 57 are metallic here being made of ferromagnetic material, such as mild steel. The shaft 13 is also made of metal made of ferromagnetic material, such as steel, which is harder than the pole wheels 54 and the core 57 of the claw rotor 12. The winding mounted on the core 57 is powered via a voltage regulator 62 which can be mounted on the hood as shown in FIGS. 38 and 41.

As can be seen in FIG. 41, brushes 60 belonging to one or more brush holders 61 are arranged so as to rub on slip rings 63. The brush holder 61 is electrically connected to the voltage regulator 62. When the excitation coil 58 is electrically powered from the brushes 60, the rotor 12 is magnetized and becomes an inductor rotor 12 with formation of magnetic north-south poles at the claws and therefore the teeth 56 of the pole wheels 54. rotor 12 inductor creates an alternating induced current in the stator 16 induced when the shaft 13 rotates. The electronic rectification module 46 then makes it possible to transform the induced alternating current into a direct current, in particular to supply the loads and the consumers of the on-board network of the motor vehicle, as well as to charge the vehicle battery. This rotor 12 may comprise permanent magnets interposed between two teeth 56 adjacent to the outer periphery of the rotor 12. These magnets may be made of rare earth or ferrite. Alternatively, the rotor 12 may be devoid of such magnets.

Moreover, as is clearly visible in FIG. 1, the cradle 1 1 delimits an open volume 64 such that the stator assembly 16, shaft 13 and rotor 12 can be respectively deposited in abutment on the bearing surface 20 and the guide bearings 21 in a mounting direction M1 perpendicular to the axis X2 of the cradle 1 1. The assembly is such that, while the stator 16 rests on the bearing surface 20, the axis X3 of the stator 16 coincides with the axis X2 of the cradle January 1. In addition, while the rotor shaft 13 rests on the guide surfaces 21, the axis X1 of the rotor 12 coincides with the axis X3 of the stator 16 and the axis X2 of the cradle January.

For this purpose, as can be seen in Figures 6 and 7, the cradle 1 1 has a central portion 65 defined at its axial ends by two side walls 68 in the form of disc portion each comprising a guide surface 21 of the The central portion 65 in the form of a cylinder portion extends at an angle of revolution of the order of 180 degrees. More generally, the cradle 11 may extend at a first angle equal to or less than 180 degrees. In a particular example, to minimize the amount of material used to make the machine, the cradle 1 1 extends at an angle less than 170 degrees. The central portion 65 of the cradle January 1 has a shape delimited by two concentric circles, which limits the amount of material used for the realization of the electric machine. Only the shape of the inner periphery of the central portion of the cradle is imposed to receive the stator 16. Consequently, in a variant, the outer periphery of the central portion 65 may have another shape such as a rectangular shape. The diameter Dbi of the inner periphery of the cradle 1 1 and therefore of the inner periphery of the central portion 65 of the cradle 1 1 corresponds to the external diameter Dce of the yoke 35 of the stator 16. In addition, an axial width Lsp of the surface of range 20 corresponds preferably to the axial width of the yoke 35 of the stator 16.

Furthermore, the guide surfaces 21 formed in the side walls 68 of the cradle January 1 delimit portions of the cylinder. The roll portions extend about 180 degrees and in all cases at an angle greater than 170 degrees. The diameters of the guide surfaces 21 may be equal or different to accommodate the differences in diameter of the shaft 13 and corresponding bearings 22. As illustrated in FIG. 9a, the guide surfaces 21 comprise a face 21 1 receiving the bearing 22 having a width substantially corresponding to the width of the outer ring of the bearings 22. An opposite face 212 of the guide lands 21 may comprise preferably cooling fins 70 extending inside openings 71 made in the side walls 68 to allow the passage of an air flow generated by fans 178 fixed on the axial ends of the rotor 12 like this is explained in more detail below. This increases the service life of the ball bearings 22.

As can be seen in Figure 9b, the central portion 65 may also include through openings 72 made in its wall. Two series of openings 72 may for example be respectively performed on either side of the bearing surface 20, to allow the passage of the cooling air flow of the machine 10. The cooling fins 73 may also be made to extend at least partially inside these openings 72. The fins 70, 73 are made of material with the cradle 1 1 so that the fins 70, 73 may be machined at the same time as the cradle 1 1. Alternatively, the fins 70, 73 are reported relative to the cradle January 1.

The cradle 1 1 is preferably monobloc, that is to say that its different parts of the cradle 1 1 are made in one piece. The cradle 1 1 may for this purpose be obtained by foundry. The cradle 11 is preferably made of a heat-conducting metallic material, such as for example an aluminum-based material.

According to the embodiment shown in FIG. 14, the yoke 35 of the stator 16 has an inner periphery 50 and an outer periphery 51. These inner and outer peripheries 50 and 51 are eccentric with respect to each other. Thus the axis X3 of the inner periphery 50 (which corresponds to the axis of the stator 16) is offset relative to the axis X4 of the outer periphery 51. The outer periphery 51 of the yoke 35 is arranged in the cradle January 1, so that the axis X3 of the inner periphery 50 is coaxial with the axis X1 of the rotor 12. The yoke 35 is oriented angularly around the X2 axis of the cradle 1 1, along the arrow F1, so that the axis X3 of the inner periphery 50 is coaxial with the axis X1 of the rotor 12 and with the axis X2 of the cradle. The outer periphery 51 of the yoke 35 is machined to present said eccentricity. Such a configuration thus makes it possible to guarantee the coaxiality of the various elements of the machine while minimizing the gap 17.

The inner periphery of the cradle 1 1 is in contact at least locally, via the bearing surface 20, with the outer periphery of the yoke 35 of the stator 16. The cradle 1 1 has one or more continuous bearing zones 75 of the stator 16 formed in the bearing surface 20 of the stator 16, as illustrated by Figures 8a to 8d. A ratio between the surface of the support zones 75 and the bearing surface 20 is for example between 5% and 100%. The heat generated by the stator 16 is discharged by conduction by the cradle January 1 due to the thermal contact between the two elements.

In the case where the cradle January 1 has several bearing zones 75, it is possible to provide an air flow passage zone between the stator 16 and the cradle January 1. This zone can be brewed by the air coming from the fans 178 or from an external ventilation source. In addition, it is possible to pass connectors or set up temperature probes, for example CTN type, in the spaces 76 between two support zones 75 consecutive to measure the temperature of the stator 16. This also reduces the machining costs due to the small surface to be machined. The bearing zones 75 may for example have the form of two projecting annular bands extending along the two axial end edges of the bearing surface 20 of the cradle (see Figure 8a). In the embodiment of FIG. 8b, the bearing zones 75 are formed by elongated ribs extending along the entire width of the bearing surface 20. In the embodiment of FIG. support 75 are formed by projecting helical portions. In the embodiment of FIG. 8d, the bearing zones 75 are formed by substantially square protuberances centered with respect to the bearing surface 20 and regularly spaced apart from one another. These examples are of course not limiting and the support zones 75 may have other configurations adapted to the architecture of the machine 10. Preferably, the cradle 1 1 incorporates an anti-vibration function to reduce acoustic noise such as that the magnetic noise related to the electrical excitation of the stator 16 and the aerodynamic noise generated mainly by the fans 178 of the rotor 12. This function can be achieved by the radial and / or axial positioning of one or more elements of damping 78 in the cradle January 1, as illustrated in Figures 1 1 to 1 1 d.

Each damping element 78 may for example take the form of a resin deposited in the cradle January 1 or antivibration pads placed in the cradle January 1. The damping elements 78 may be of liquid or solid or viscoelastic nature, organic materials, polymers, elastomers or composites such as silicone, rubber, plastic, or any other suitable material for the application. The material of the damping element 78 may if necessary include a thermal conduction function towards the cradle January 1.

The contact surface of the damping element 78 with the yoke 35 is between 2% of the surface of the stator 16 inserted in the cradle January 1 and 95% of the surface of the stator 16. The elements 78 can be set place at an angle between 0 and 180 ° with respect to the axis X3 of the body 31 of the stator 16. The antivibration elements 78 on the cradle 1 1 can be held by bonding, or simply by compression with the stator 16 during assembly.

In the embodiment of Fig. 11a, the damping members 78 are formed by square shaped elastomeric pads spaced from each other in a regular manner. In the embodiment of FIG. 11b, the buffers 78 are interconnected by a strip of material. In the embodiment of FIG. 11c, the damping elements 78 are inserted inside recesses 79 of complementary shape formed in the bearing surface 20. In the embodiment of FIG. a seal is inserted inside a groove made in the bearing surface 20 of the cradle January 1.

Figures 12a to 12d show different configurations of recesses 79 can be made in the bearing surface 20 to incorporate damping elements 78 of corresponding shape. In the embodiment of Figure 12a, the recess 79 is elongated and located in a central area of the bearing surface 20. In the embodiment of Figure 12b, the recesses 79 have circular shapes regularly spaced from each other. In the embodiment of FIG. 12c, the recesses 79 consist of two grooves located on the side of the axial edges of the bearing surface 20. In the embodiment of FIG. 12d, the recesses 79 have helical shapes. Any other type of recess 79 is of course conceivable.

In the embodiment of FIG. 4a, referred to as the "buried stator", an inner face 81 of the cradle 1 1 extending partly around the stator 16 is raised relative to the bearing surface 20 of the stator 16 which then constitutes the bottom from the cradle 1 1. The inner face 81 is elevated by a given thickness E1, so that the distance L1 between the outer circumference of the buns 41a, 41b of the stator 16 and the inner periphery of the cradle 1 1 is decreased by a value proportional to said E1 thickness. The invention thus provides a more compact assembly to facilitate the integration of the machine in the under-hood space of the vehicle. In all cases, the distance L1 between the outer circumference of the buns 41a, 41b of the stator 16 and the inner periphery of the cradle 1 1 extending around the stator 16 is preferably sufficient for an airflow blade to propagate around the buns 41a, 41b.

In the embodiment of Figure 4b called "raised stator", the bearing surface 20 of the stator 16 is raised relative to a bottom 82 of the cradle 1 1 extending in part around the stator 16. The bearing surface 20 of the stator 16 is raised relative to the bottom 82 of a given thickness E2 so that a distance L2 between the outer circumference of the bunches 41a, 41b of the stator 16 and an inner periphery of the cradle January 1 is increased by one value proportional to said thickness E2. The elevation of the stator 16 can be obtained for example by the realization of the bearing areas 75 projecting. The invention thus makes it possible to guarantee a minimum distance between the cradle 1 1 and the winding 40 of the stator 16 without having to carry out a shaping operation of the buns 41a, 41b, which increases the exchange surface and thus improves the cooling of the machine. Preferably, the minimum space requirement ratio K2 between the outer radial casing of the front bun 41 a and the cradle 11 is equal to K2 = (Dbi) / (Dch), Dch being the outside diameter of the front bun 41 a and Dbi being the inside diameter of the cradle 1 1. The ratio K2 is in the interval following 1 .005 <K2 <1 .15. The minimum space requirement ratio K3 between the outer radial casing of the rear bun 41b and the cradle 11 is equal to K3 = (Dbi) / (Dch '), Dch' being the outside diameter of the rear bun 41b and Dbi being the inside diameter of the cradle 1 1. The K3 ratio is in the range 1 .005 <K3 <1 .15.

The volume guaranteeing a sufficient air flow cooling the front bun 41 a corresponds to a distance L3 in millimeters between 0.2 ^* K2 and K2.

The volume guaranteeing a sufficient air flow cooling the rear bun 41 b corresponds to a distance L4 in millimeters between 0.2 ^* K3 and 2 ^* K3. In addition, the cradle January 1 may if necessary be cooled by a coolant. For this purpose, the cradle 11 may include in its internal structure channels 83 (see FIG. coolant taking for example the form of water containing antifreeze or an oil-based liquid.

As can be seen in Figures 1, 2, 6, 7 and 9a in particular, the cradle 1 1 has in its lower part ears 84 provided with a hole allowing the passage of fixing means to allow the attachment of the alternator 10 on the vehicle chassis in a sub-hood environment.

Advantageously, the cradle January 1 has reference pads 85 visible in Figures 10a and 10b positioned at the ears and near the end edges of the central portion 65 which extend perpendicularly to the side walls 68. These pads 85 allow to locate the positioning of the cradle 1 1 during a machining phase.

As illustrated in FIGS. 1, 2, 15, and 16 in particular, the holding member 26 of the stator 16 has a tab 87 attached relative to the cradle 11. The purpose of the tag 87 is to maintain the stator 16 on the cradle 1 1.

The trellis 87 of the stator 16 has in this case a cylinder portion shape extending at an angle greater than 170 degrees; for example of the order of 180 °. In some embodiments, the angular range over which the cylinder portion of the tag 87 extends is greater than 200 degrees. This optimizes the shape of the cradle January 1, which reduces the weight of aluminum necessary for the realization of the machine. In other words, the slam 87 has a shape complementary to the cradle.

Furthermore, in one exemplary embodiment, the width I cl of the slab 87 is between 0.5xLc and 1.5xLc, Le being the axial width of the yoke 35 of the stator 16. In addition, the slam 87 may be centered or not with respect to a median plane of symmetry perpendicular to the axis X3 of the stator 16. The length L cl of the string 87 depends on the width I cl of the cradle 1 1 where the stator 16 is housed and the diameter of the screw. The string 87 has a solid part having a thickness E_cl of between 0.2 mm and 2 times a thickness of the yoke 35 of the stator. The use of a slab 87 of fine thickness is permitted because the stator 16 has no mechanical stress. In an exemplary embodiment, a ratio between an internal diameter D_cl of the label relative to the internal diameter Dbi of the cradle January 1 is between 0.9 and 1 .1.

In order to ensure a positioning under control of the tag 87, it is preferred to use complementary indexing means 88 of the holding member 26 relative to the cradle January 1. For this purpose, as illustrated in FIGS. 17a and 17b, and 18, the indexing means 88 comprises pins 89 positioned at the two ends of the slam 87 intended to cooperate with grooves 90 of corresponding shape made in the edges. from the cradle 1 1. Alternatively, the positioning of the pins 89 and grooves 90 could of course be reversed, so that the pins 89 are formed in the cradle January 1 and the grooves formed in the end edges of the slam 87. As shown in FIG. 19, the band 87 may also be provided with a groove 91 in order to guarantee the positioning of the body 31 of the stator 16.

In order to allow the fixing of the string 87 on the cradle January 1, the string 87 is here provided with two extra thicknesses 94 at its ends in which are formed holes 95, as is clearly visible in Figures 15 and 17b in particular. These holes 95 allow the passage of fastening means, such as screws, inserted into corresponding holes 96 made in the cradle January 1. Advantageously, the tag 87 is fixed on the cradle January 1 by means of Belleville washer to exert a constant effort and absorb the machining tolerances. Alternatively, the clam 87 is fixed by any other means on the cradle January 1, such as by riveting, welding, or gluing.

Alternatively, the holding member 26 has a plurality of tabs 87. In the example shown in FIG. 22, two tabs 87 of identical width are mounted parallel to each other and slightly apart from each other. other. However, alternatively, it will be possible to use more than two tags 87 which may have different widths if necessary.

In the embodiment of FIGS. 1, 15, 16 and 23, the alarm 87 is configured to allow conductive cooling of the stator 16. For this purpose, the inner periphery of the alarm 87 is in contact with the outer periphery of the the cylinder head 35 of the stator 16. The plate 87 is made of preferably in a thermally conductive material for evacuating the calories when the slam 87 is in contact with the yoke 35 of the stator 16. The slam 87 may thus be made of a material based on steel or aluminum, or in a composite material. In addition, the holding member 26 includes a cooling device 100 for evacuating the stored calories. The cooling device 100 comprises convection cooling means provided for example with fins 101 (see FIGS. 20a and 20b) in order to increase the exchange surface with air. In an exemplary embodiment, the fins 101 may have a height H_a between 0.1 and 30mm, and a width L_a between 0.1 and 20mm. The angular spacing between two successive fins 101 may be between 2 and 180 degrees. In addition, the spacing E_a between two shapes is between 0.5 and 47mm. The number of fins 101 formed on the string 87 is between 1 and 80.

These fins 101 may be integrated or reported relative to the plate 87. The dissipator function is preferably performed on the entire outer surface of the plate 87 off the bearing surface on the cradle January 1. It is nevertheless conceivable to make fins 101 in the inner surface of the slug 87 facing the yoke 35 of the stator 16.

If necessary, a silicone-based thermal paste can be added to improve the thermal conductivity and consequently the cooling of the stator 16 by the tag 87.

In the embodiment of FIG. 21, the cooling device 100 comprises a cooling circuit integrated in the string 87. For this purpose, conduits 102 are formed in the string 87 to allow the circulation of a cooling liquid, such as water containing antifreeze or an oil-based liquid. The cooling circuit can be obtained either by overmolding the material of the clam on the conduits 102, or by adding on the plate 87 an additional circuit.

The calliper 87 is obtained by machining for the faces used for fixing on the cradle January 1. In the case of a process for obtaining by foundry, the form raw material may have reference pads that will be used in machining for the clamping system (on one side).

In the embodiment of Figure 23, the slam 87 is rotatably mounted relative to the cradle 1 1 via a hinge 105 allowing the rotation of the slam 87 relative to the cradle 1 1 about an axis parallel to the axis X2 from the cradle 1 1. The displacement of the tag 87 can thus be carried out according to the arrow F2. The slam 87 can thus pass from a position in which the slam 87 is moved away from the cradle 1 1 corresponding to an unlocked state to allow the insertion of the stator 16 into the recess delimited by the cradle January 1, at a position in which the 87 is fixed on the cradle 1 1 corresponding to a locked state in which the slug 87 keeps tight the yoke 35 of the stator 16 between the bearing surface 20 of the stator 16 and the slam 87. For this purpose, the slam 87 has a protuberance 106 on the opposite side of the hinge 105. The protrusion 106 is provided with an opening 107 for the passage of a screw 108 for securing the clamp 87 on the cradle January 1. This ensures a clamping radial and axial retention of the stator 16 of the machine.

In addition, the speaker 87 may, like the cradle 11, preferably provide an anti-vibration function to reduce acoustic noise, such as the magnetic noise related to the electrical excitation of the stator and the aerodynamic noise generated mainly by the fans 178 of rotor 12.

This function can be achieved by the radial and / or axial positioning of at least one damping element 1 1 1 in the frame 87, as illustrated in FIGS. 24a and 24b. These damping elements 1 1 1 may consist of a resin deposited in the frame 87 or buffers positioned in the frame 87.

The damping elements 11 may be liquid or solid or viscoelastic nature, organic materials, polymers, elastomers or composites such as silicone, rubber, plastic. The material of the antivibration element 1 1 1 may provide a thermal conduction function to the cradle January 1. The contact surface of the damping element (s) 11 may be between 2% and 95% of the surface of the body 31 of the stator 16 inserted into the plate 87.

The elements 1 1 1 can be set up at an angle of between 0 and 180 degrees relative to the axis X3 of the stator 16. The antivibration elements 1 1 1 hold on the plate 87 can be made by gluing, or simply by compressing the stator 16 during assembly.

FIG. 24a thus illustrates the introduction of a rubber seal along the length of the slug 87. FIG. 24b illustrates the placement of a series of buffer 1 1 1. Damping elements January 1 having a configuration similar to the damping elements 78 of the cradle January 1 may also be integrated into the frame 87.

In the variant embodiments of FIGS. 25a and 25b, the stator 16 is held axially by flanges 1 12 of the string 87 extending along the axial end edges of the string 87. A damping element 1 1 1 O-ring type is further disposed in a corner January 13 of the slam 87 defined by the intersection between a flange 1 12 and the inner periphery of the slam 87, so that the seal 1 1 1 is crushed between the slam 87 and the stator 16. In the embodiment of FIG. 25a, the edge 1 14 of the corresponding yoke 35 of the stator 16 is beveled. In the embodiment of FIG. 25b, the edge 14 of the yoke 35 has shoulders against which the gasket 11 1 bears. The flanges 1 12 thus make it possible to improve the axial retention of the stator 16 on the cradle January 1.

In the embodiment of FIG. 25c, the string 87 and the yoke 35 of the stator 16 respectively comprise a groove 1 15, 1 16. These grooves 1 15, 1 16 are positioned facing each other. the other. A snap ring 1 17 is inserted inside these grooves 1 17. This snap ring 1 17 bears against the faces of radial orientation delimiting these grooves 1 15, 1 16 thus makes it possible to maintain axial of the body 31 of the stator 16 on the cradle 1 1.

In a variant, as illustrated in the embodiments of FIGS. 26 to 30, the architecture of the machine 10 is devoid of any label 87. The holding member 26 then comprises excrescences 122 coming from the yoke 35 of the stator 16 to allow the stator 16 to be held on the cradle 1 1.

More precisely, in the embodiment of FIG. 26b, the body 31 of the stator 16 comprises two protrusions 122 which are substantially diametrically opposed and projecting from the outer periphery of the yoke 35. The two protuberances 122 are substantially symmetrical one compared to each other. Once the stator 16 is deposited in the cradle January 1, two locking devices 123 provide a maintenance of the protrusions 122 against the cradle January 1. The locking devices 123 may be screwed, riveted, or welded to the cradle 11. Alternatively, other device assembly systems 123 on the cradle 1 1 may be used, it depends on the application. The locking devices 123 may be made for example in a material of aluminum, steel or composite materials. These shapes 122 may also be used for stator indexing 16 in the winding processes, and in the methods of assembling the stator 16 in the cradle January 1.

In the embodiment of FIG. 27, one of the protuberances 122 is pierced by a hole 125 perpendicular to the surface of the laminations of the body 31 of the stator 16 to receive a rod 124 integral with the cradle 1 1 penetrating the hole 125, of such way that the body 31 of the stator 16 can pivot about an axis of the rod 124 parallel to the axis X3. The second growth

122 is intended to cooperate with a locking device 123 for clamping the stator 16 on the cradle January 1. As before, the blocking device

123 can be screwed, riveted, or welded to the cradle 1 1. In the embodiment of FIG. 28, the two protuberances 122 each comprise a bore 127 parallel to the surface of the sheets of the body 31 to allow the passage of a fixing element 128, of the screw or rivet type, for example. The fastening elements 128 can thus ensure a direct attachment of the stator 16 to the cradle January 1. In the embodiment of FIG. 29, a protuberance 122 in the shape of a U is intended to cooperate with the rod 124 integral with the cradle January 1, so that the body 31 of the stator 16 can pivot about an axis of the stem

124 parallel to the axis X3 when placing the stator 16 in the cradle 1 1. The second protrusion 122 is intended to ensure a fixation of the stator 16 on the cradle January 1, either by the use of a locking device 123 associated, or, as shown, by the use of a fastener 128 through a bore 127 made in the protrusion 122 in a manner direction substantially parallel to the sheet metal sheets of the body 31. As is clearly visible in FIG. 31 a, 31 b and 32, each bearing holding device 23 connected to the cradle 11 is constituted by a frame 131 each intended to cooperate with one of the corresponding guide lands 21. These tabs 131 define cylinder portions complementary to the cylinder portions delimited by the guide lands 21 so as to grip each bearing 22 (see Figure 2). Each clam 131 is thus configured to keep the outer race of the bearing 22 tight between the guide surface 21 and the clam 131.

For this purpose, each frame 131 comprises a bridge 132 extending between two ends 133 which are fixed on the cradle 1 1 on either side of the guide surface 21. The fastening means 134 of the frame 131 on the cradle 1 1 may for example be constituted by screws or rivets for passing through openings 135 made in thicker ends 133 to cooperate with corresponding holes made in the cradle 136. The bridge 132 is delimited at its inner periphery and its outer periphery by concentric circles. A ratio between a thickness Ep of the bridge 132 with respect to an internal diameter Dpi of the bridge (cf Figure 31b) is between 0.05 and 0.3. Advantageously, a thickness Ep of the bridge 132 is between 0.2 and 3 times the thickness of the inner ring of the bearing 32. Thus, the clam 131 is sized to withstand the efforts of the application because the thickness of the inner ring is directly related to these efforts.

It should be noted that the axis X6 of the claws 131, corresponding to the axis of the inner periphery 132 of the bridge 132, coincides with the axis of the corresponding bearing 22. Preferably, the axial width Lp of the tongue 131 (see FIG. 31 a) is substantially equal to the axial width of the outer race of the bearing 22.

Furthermore, so that the claws 131 do not interfere with the air flow generated by the fans 178 each mounted on an end face of the 12, each clam 131 has a height less than the circumference along which are located the inner ends of the blades of the fans 178.

To facilitate assembly, an indexing means 138 of the holding device 23 is preferably provided with respect to the cradle 11. As can be seen in FIG. 33, this indexing means 138 is constituted by a tongue 139 intended to cooperate with a corresponding groove 140 formed in the cradle 11.

Clades 131 may be steel, aluminum, or composite materials, The clam 131 is obtained by machining for the faces used for attachment to the cradle January 1. In the case of a process for obtaining by casting, the raw form may have reference pads formed in the ends 133 which will be used during machining for the clamping system. The bearing retainer 23 further preferably comprises a heat sink 143 as shown in Figs. 36a, 36b, 37a, 37b, and 37c. Such a dissipator 143 improves the life of the bearings 22 and also allows bearings 22 with reduced clearance, which has a vibratory influence on the operating noise that is minimized.

This heat sink 143 may be positioned on the entire outer surface of the clam 131 off the bearing surface on the cradle 131. In this case, the heat sink 143 is positioned on the outer periphery of the bridge 132. This heat sink comprises a plurality of fins 144. In an exemplary embodiment (see Figure 36b), the fins 144 may have a height H_a 'between 0.1 and 30mm, and a width L_a' between 0.1 and 20mm. The angular spacing between two successive fins 144 may be between 2 and 180 degrees. In addition, the spacing E_a 'between two shapes is between 0.5 and 47mm. The number of fins 101 formed on the clam 131 is between 1 and 90. Figures 37a to 37c illustrate different types of configurations of fins 144. The claws 131 may have a full central wing 144 'more thicker than the lateral wings 144, as illustrated in Figures 37a and 37b.

The heat sink 143 comprising the fins 144, 144 'may be attached to the frame 131 or come of material with the clam 131. A thermal paste, for example based on silicone, can be added to improve the thermal conductivity of the claws 131 and consequently the cooling of the bearings 22.

Preferably, a thrust bearing system 148 makes it possible to hold each bearing 22 axially relative to the cradle January 1. This abutment system 148 is integrated on the bearing retaining device 23 and / or on the guide surfaces 21 of the cradle 11. Thus, in the embodiment of FIGS. 34 and 35, the abutment system 148 comprises a retaining ring 149 cooperating on the one hand with a groove 150 formed in the corresponding tab 131 and on the other hand with a groove 151 in vis-à-vis performed in the bearing 22 corresponding. The groove 151 is more precisely made in the outer ring 221 of the bearing 22, as is shown in the detailed view of FIG. 35. The stop system 148 thus ensures an axial retention of the bearing 22 taking into account the bearing of the bearing. ring 149 against the faces of radial orientation delimiting the grooves 150, 151. Alternatively, as shown in Figure 13, the stop system 148 may belong to the cradle January 1. In this case, the abutment system 148 comprises annular shoulders 154 formed in at least one axial end of the guide lands 21 and against which bears a bearing 22 corresponding. Thus, the shoulders 154 may be made on one axial side or on both axial sides of each guide surface 21.

As can be seen in FIG. 38, the cover 30 has a central portion 157 having a cylinder portion shape and two side walls 158 situated at the two axial ends of the central portion 157. The side walls 158 in the form of disk portions have notches 159 to allow an axial passage of the air inside the machine 10. through openings 160 better visible in Figure 2, are formed in the central portion 157 to allow a radial discharge of the air flow generated by the fans 178, as described below. Feet 161 delimiting the corners of a rectangle are intended to bear against the corresponding edges of the cradle January 1. The hood 30 essentially has a function of protecting the machine from its outside environment. This cover 30 is assembled radially on the cradle 1 1 and / or the tab 87 of the stator 16 and not axially as is the case with the front and rear bearings of existing machines. The cover 30 may be fixed on the cradle 1 1 and / or the tab 87 by riveting, thermo-bonding, screwing, or clipping, welding, bonding crimping, strapping, hooping, brazing, or stamping.

More specifically, in the case of a cover 30 made of a plastic material, the fixing thereof may be carried out using a metal insert on which is molded the plastic mass forming the cover 30 and screwed on the cradle 1 1, by thermoforming the cover 30 on the cradle 1 1 and / or the tab 87 of the stator 16 or by heat-sealing the cover 30 on the cradle 1 1 and / or the slam 87, or by riveting the plastic cover 30 on the cradle 1 1 and / or the claim 87.

Alternatively, the cover 30 may be made of a metallic material, such as aluminum or steel. The cover 30 may be provided with a sound-insulating device 162 made for example of a foam-based material, or a honeycomb-shaped material.

As is illustrated in FIG. 41, a brush holder 61 secured to the cover 30, in this case a side wall 158, comprises brushes 60 intended to rub against rings 63 carried by the shaft 13 and made for example in a copper-based material. In an advantageous embodiment shown in dotted lines, the cover 30 comprises at each of its ends a brush holder 61 each comprising a brush 60 cooperating with a ring 63 located at each axial end of the rotor 12. The positioning of the pulley 14 is then adapted accordingly. Preferably, each brush holder 61 is provided with a protector integrated in the cover 30. The protector makes it possible to retain the dust of the brushes 60. Each brush holder 61 preferably comprises at least one duct guiding a passage of an air flow towards the brushes 60 and rings 63. This thus makes it possible to increase the service life of the brushes 60. The regulator 62 of FIG. The voltage of the rotor 12 generating the voltage applied by the brushes 60 is advantageously mounted on the cover 30. It will be possible to take advantage of the cover 30 made of a plastic material to overmold the regulator 62 on the cover 30.

The hood 30 may, like the cradle 11, comprise cooling channels 301 in which a cooling liquid circulates so as to evacuate the heat produced by the rings 63 and the electronic control module 46.

Preferably, as illustrated in FIG. 39, the electronic rectification module 46 is offset radially relative to a yoke 35 of the stator 16. The electronic rectification module 46 extends at least partially in a plane P1 parallel to a X3 axis of the cylinder head 35 and located at a radial distance from the stator 16 greater than that of the outer periphery of the cylinder head 35. The electronic rectification module 46 may extend at least partially in a surface of a cylinder of revolution centered on the axis of the stator 16 parallel to the yoke 35 and located at a radial distance from the axis of the stator 16 greater than that of the outer periphery of the yoke 35.

The electronic rectification module 46 is preferably mounted on the frame 87 of the stator 16. The rectifying elements 47 of the diode or transistor type are advantageously positioned axially on either side of the plate 87 in order to cooperate with the phase outputs 171. whose positioning is described in more detail below. The positive rectifying elements 47a can thus be positioned on the same side of the plate 87; while the negative rectifier elements 47b can be positioned on the opposite side. As a variant, the electronic rectification module 46 may be fixed or overmoulded in the cover 30. The cover 30 may then include traces 174 (see FIG. 38) overmolded to be electrically connected to the electronic rectification module 46. heat dissipation can also be overmolded on the hood 30 to ensure proper operation of the rectifier elements 47 of the diode type or MOSFET transistor.

Advantageously, as illustrated by FIG. 40a, the phase outputs 171 of the winding 40 are bent with respect to the axis X3 of the stator 16 by an angle A_ph of between 45 ° and 120 °. The phase outputs 171 are curved with respect to the axis X3 of the stator 16 by an angle A_ph preferably of the order of 90 degrees. This avoids passing the phase outputs 171 along the circumference to put them next to an interconnector, which greatly facilitates the mounting of the alternator 10. In addition, as shown in Figure 40b, the Phase outputs 171 may be positioned indifferently on the front side or the rear side of the alternator 10. Preferably, the phase outputs 171 are distributed axially on either side of the stator 16. The phase outputs 171 are thus distributed. at both axial ends of the stator 16. Thus, flexibility is obtained for the phase outputs, that is to say that it is possible to distribute the outputs of the two axial sides of the stator. In the particular case of a distributed corrugated winding, the stresses are thus minimized, because it is no longer necessary to turn around two notches to exit the phases on the same side. In addition, the phase outputs 171 may thus be connected to the corresponding series of rectifying elements 47a, 47b.

When the electronic rectification module 46 is mounted on the tab 87 of the stator 16, the tag 87 is able to conditively cool the electronic rectification module 46. In addition, the cooling device 100 is provided to remove the heat generated by the alternator 10 and the electronic module 46. The cooling device 100 comprises means 177 generating a forced axial air flow capable of generating a flow of air evacuating radially after having convectively cooled the electronic rectification module 46.

For this purpose, the means 177 comprise two fans 178 each mounted on an axial end face of the rotor 12. Each fan 178 clearly visible in Figure 42 is provided with a plurality of blades 180. A central opening 181 allows the passage of the shaft 13. Each fan 178 preferably made of plastic is fixed for example by gluing or riveting on the end faces of the rotor 12. As shown in FIG. 3, the fans 178 are able to generate a flow of air penetrating axially, according to the arrows F3, inside the machine via the open side walls of the cover 30 and the cradle January 1, and evacuating radially after having convectively cooled the electronic rectification module 46 outwards along the arrows F3 via the openings 72, 160 respectively formed in the cradle 11 and the cover 30.

In the embodiment of FIG. 43a, the cover 30 comprises an air inlet duct 185, so that the air can enter radially into the machine 10 via this duct 185 and axially on the opposite side according to the arrows F3. to be discharged radially via the openings 72 and 160, according to the arrows F4. The side face of the cover 30 located on the side of the conduit 185 may in this case be closed.

In the embodiment of FIG. 43b, the cover 30 comprises two radial air inlet ducts.

Alternatively, the rotor 12 comprises a single fan 178 fixed on one of its axial ends.

In addition, an annular radiator (see Figure 3) reported for cooling the air entering the machine 10 can be positioned on each side of the cradle January 1. The radiator may be in relation to the passenger compartment of the vehicle to provide heat if necessary. The corresponding coolant circulation ducts are referenced 189 in FIG.

If necessary, at least one electric fan 187 may be radially offset, in order to cool the electronic rectification module 46. The electric fan 187 is fixed for example on the cover 30 so as to direct its air flow towards the electronic module 46. The electric fan 187 may for example be a fan supplied with low voltage of the order of 12V to 48V.

Although the invention has been described with reference to an alternator, it is clear that the invention can be implemented with any other type of electrical machine, such as an electric motor. In order to produce the rotating electrical machine 10, a machining step is carried out in the cradle 1 1 of the bearing surface 20 of the stator 16, as well as a machining step in the cradle 11 of the positioned guide lands 21 respectively axially respectively on either side of the bearing surface 20 of the stator 16. The machining steps of the cradle January 1 are performed during a single machining operation. Thus, the machining steps of the cradle January 1 are performed at the same time or at least without debridement of the workpiece during machining. The cradle 1 1 thus has corresponding traces of machining. The stator assembly 16, shaft 13 and rotor 12 is then respectively mounted in abutment on the bearing surface 20 and the guide surfaces 21 in the mounting direction M1 perpendicular to the axis X2 of the cradle January 1.

The invention thus makes it possible to group all the bearing surfaces, that is to say the guide bearing surfaces 21, and the stator bearing surface 20 on the same part 1 1 which is machined to make all these spans advantageously at one time. in any case on the same machining machine without debriding the part. From a dimensional point of view, the invention thus makes it possible to eliminate the following sets: the mounting set of the rear bearing, and the mounting set of the front bearing of the machines of the state of the art. The clearances of the two guide lands 21 and the two lands of the stator 16 are also reduced because they are obtained by machining. It also removes the sum between the play on the guide surface 21 and the play on the scope of the stator 16, because the staves are machined on the same part with the same reference.

Insofar as the following sets are correlated, namely the play of the bearing surface 21 receiving the bearing 22, the play on the bearing surface of the front bearing receiving the stator 16, and the play of the bearing surface 21 receiving the bearing 22, we obtain thus an air gap 17 which must be greater than the values below:

a first value obtained by the sum of the following sets: the clearance of the bearing surface 21 receiving the bearing 22, the play of the front bearing 22, the clearance on the external diameter of the stator 16, the clearance on the internal diameter of the stator 16, the clearance on the outer diameter of the rotor 12,

a second value obtained by the sum of the following sets: the play on the bearing surface of the front bearing receiving the stator 16, the clearance on the outer diameter of the stator 16, the clearance on the internal diameter of the stator 16, the clearance on the diameter outer rotor 12, and a third value obtained by the sum of the following sets: the clearance of the bearing surface 21 receiving the bearing 22, the clearance of the rear bearing 22, the clearance on the outer diameter of the stator 16, the clearance on the internal diameter of the stator 16, and the clearance on the outer diameter of the rotor 12. From the geometric point of view, the invention makes it possible to reduce the alignment constraint on three diameters instead of four. This results in a reduction or even a suppression of the problems of coaxiality of the bearing surfaces (guide surfaces 21, and the bearing surface 20 of the stator 16) between them. Accordingly, in the invention, the air gap 17 must absorb only the above games, which greatly reduces the problems of coaxiality. The gap 17 can therefore be substantially reduced without risk of destruction of the electric machine 10.

Claims

1. A rotating electrical machine, comprising a stator (16) and a rotor (12) mounted on a shaft (13), characterized in that said rotating electrical machine further comprises a cradle (1 1) having a bearing surface (20) of stator (16) and at least one rotatable guide surface (21) of said shaft (13), in that said shaft (13) is mounted on the guide surface (21) via a rotation guide system (22) , and in that said rotating electrical machine further comprises at least one holding device (23) of said rotational guiding system (22), said holding device (23) having a clam (131).

2. Electrical machine according to claim 1, characterized in that said rotational guiding system (22) comprises a bearing and in that said holding device (23) is configured to hold tight an outer cage of said bearing (22) between said guide surface (21) and said holding device (23).

3. rotary electric machine according to claim 1 or 2, characterized in that said rotational guiding system (22) comprises a bearing and in that an axial width of said holding device (23) is substantially equal to an axial width an outer race of the bearing (22).

4. A rotary electric machine according to any one of claims 1 to 3, characterized in that said holding device (23) of the rotational guiding system (22) is attached relative to said cradle (1 1).

5. rotary electric machine according to any one of claims 1 to 4, characterized in that said frame (131) comprises a bridge (132) extending between two ends (133) fixed on said cradle (1 1).

6. rotary electric machine according to claim 5, characterized in that a ratio between a thickness (Ep) of said bridge (132) with respect to an inner diameter of said bridge (Dpi) is between 0.05 and 0.3.

7. rotary electric machine according to claim 5 or 6, characterized in that said rotation guide system (22) comprising a bearing having an inner ring, a thickness (Ep) of said bridge (132). is between 0.2 and 3 times the thickness of said inner ring of the bearing.

8. rotary electric machine according to any one of claims 1 to 7, characterized in that said holding device (23) of the rotational guiding system (22) has a lower height relative to a fan (178).

9. rotary electrical machine according to any one of claims 1 to 8, characterized in that said rotating electrical machine comprises an indexing means (88) of said holding device (23) relative to the cradle (1 1).

10. Rotating electric machine according to any one of claims 1 to 9, characterized in that said rotating electrical machine comprises at least one stop system (148) for ensuring an axial retention of the rotational guiding system (22), said abutment system (148) having a retaining ring (149) in the retaining device (23) against which the rotational guiding system is supported.

1 1. Electrical machine according to any one of claims 1 to 10, characterized in that said holding device (23) comprises a heat sink (143) having fins (144).

12. Electrical machine according to claim 1 1, characterized in that said heat sink (143) is attached relative to said holding device (23) of the rotation guide system.

13. A rotary electric machine according to claim 1 1, characterized in that said heat sink (143) is made of material with said holding device (23) of the rotation guide system.

14. A rotary electric machine according to any one of claims 1 to 13, characterized in that the cradle (1 1) comprises a heat sink (70) of the rotation guide system (22).

Rotary electric machine according to claim 14, characterized in that the guide surfaces (21) comprise a face

(21 1) receiving the rotation guiding system (22) and an opposite face

(212) having cooling fins (70).