Abstract:
An electronic module for a rotary electrical machine which applies to any type of polyphase rotary electrical machine, synchronous or asynchronous, such as alternators or alternator starters, and also whether it is a case of electrical machines for motor vehicles and driven for example by belt, with cooling by air, liquid or any other solution that can be envisaged.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to PCT Application PCT/FR2006/050485 filed May 29, 2006 and also to French Application No. 0505503 filed May 31, 2005, which applications are incorporated herein by reference and made a part hereof. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention concerns an electronic module for a rotary electrical machine. 
     The present invention applies to any type of polyphase rotary electrical machine, synchronous or asynchronous, such as alternators or alternator starters, and also whether it is a case of electrical machines for motor vehicles and driven for example by belt, with cooling by air, liquid or any other solution that can be envisaged. 
     2. Description of the Related Art 
     In a motor vehicle comprising a thermal engine and a rotary electrical machine such as an alternator starter, such an electrical machine comprises for example, non-limitatively:
         a rotor comprising a field winding into which an excitation current is brought, and   a stator comprising a polyphase winding.       

     The alternator starter functions in motor mode or in generator mode. It is a so-called reversible machine. 
     In generator or alternator mode, the machine converts a rotation movement of the rotor driven by the thermal engine of the vehicle into an electric current induced in the phases of the stator. In this case, a bridge rectifier connected to the phases of the stator rectifies the sinusoidal induced current into a DC current in order to supply consumers on the vehicle such as a battery. 
     On the other hand, in motor mode, the electric machine serves as an electric motor for rotating, via the shaft of the rotor, the thermal engine of the vehicle. It converts electrical energy into mechanical energy. In this case, an inverter converts a DC current coming from the battery into an alternating current for supplying the phases of the stator in order to rotate the rotor. 
     Control signals are used to determine the operating mode of the rotary electrical machine (motor mode or generator mode). 
     In a first prior art, in the document WO 02/060038 (corresponds to U.S. Pat. No. 6,692,278), the bridge rectifier/inverter comprises a plurality of transistors integrated in an electronic box. The electronic box is connected to the rotary electrical machine via a three-phase connecting cable. This solution is bulky having regard to the space available under the engine bonnet, and expensive because of the cable and its assembly, which represents a not insignificant additional cost. 
     In a second prior art, in the document DE 102004007395 A1, electronic components are used that are outside an external peripheral band. These components comprise power connection ends that are also inside the band. The band comprises internal partitions in which metal power interconnection tracks are molded on. These power tracks connect the components via their power ends to the battery so as to supply them. The band is positioned on the rear bearing of the machine. This solution proves to be problematic because of the cross-sections of the power interconnection tracks, which are too small compared with the current necessary, around 150 A in alternator mode and 600 A on starting, for the application of an alternator or alternator starter so that the tracks reach an excessively high temperature. 
     SUMMARY OF THE INVENTION 
     Thus an object of the present invention is to propose an electronic module that can easily be integrated on a rotary electrical machine and that can have sufficiently large conductors to withstand the currents passing through them. 
     To this end, according to a first object of the present invention, the electronic module comprises:
         a housing defined by a top face, a bottom face and at least three lateral faces;   electronic components disposed in the housing;   the electronic components being mounted on power connections, and   the power connections comprising ends that are all disposed in the vicinity of a first face of the housing.       

     Thus, as will be seen in detail below, the present invention has the advantage of being able to easily integrate an electronic module on an electronic subassembly intended to be mounted on a dissipator, integrated or not, of an electrical machine, by proposing a standard electronic module architecture necessary for the functioning of the electrical machine, whether it be a power module or a control or excitation module. 
     In addition, as the power connection ends are situated as close as possible to the outside diameter of the machine, this makes it possible firstly to obtain an available surface for placing the ends and secondly to easily connect a power interconnection piece by stacking. Such a stacking makes it possible to use a coaxial plane (coaxial with the shaft of the rotor) different from that used by the modules for the interconnection tracks so that the latter are defined independently of the space taken up by the modules and therefore can have a larger cross-section. 
     According to preferential non-limitative embodiments, the electronic module that is the object of the invention has the additional characteristics stated below:
         the machine being defined by an outside diameter and comprising:   a rotor;   a stator provided with a polyphase winding;   a shaft carrying the rotor about a rotation axis;   a bearing to which the stator and the shaft are fixed; and   a dissipator integrated or not in the bearing;   the ends of the power connections are all in the vicinity of the outside diameter of the machine;   the ends of the power connections are all disposed substantially on the same arc of a circle centered on the rotor rotation axis;   it comprises electronic power components with no housing and directly attached to the power connections;   it comprises electronic power components that form at least one arm of a bridge rectifier/inverter, an arm being intended to cooperate with a phase of the stator;   it also comprises elements controlling power electronic components;   the control elements are in an integrated circuit;   it comprises electronic components controlling electronic power components for the functioning of the rotary electrical machine;   the power connections comprise power electrical conductors for supplying the components of the module with power;   the power connections comprise at least one phase track intended to be connected to a phase of the stator;   the phase track comprises an end in line with a phase outlet of the stator;   the phase track is the only one;   the power connections comprise at least two phase tracks;   a phase track comprises an end placed between two power electrical conductors;   a phase track comprises a free end perpendicular to the track;   the free end comprises a hook that projects beyond the housing of the module;   the hook projects beyond the bottom or top face of the housing;   the bottom face carrying the electronic components and the power connections is fixed to a thermally conductive plate by means of an electrically insulating adhesive;   the power connections are visible on the bottom face of the module;       

     the power electrical conductors are flat tracks flush on the bottom face of the module;
         a power electrical conductor comprises an end parallel to the bottom face of the module and situated on a different plane;   a power electrical conductor comprises an end that is a metal insert for connecting the module to the potential of the dissipator;   a power electrical conductor comprises a free end that is perpendicular to the bottom face of the module;   the free end projects beyond the top face of the module;   it also comprises means of electrical protection of the end;   it also comprises signal connection elements intended to transmit control signals for the functioning of the machine;   the signal connection elements are in the same plane perpendicular to the bottom face of the module, the plane passing essentially through a rotor rotation axis of the machine;   it also comprises signal connection elements that are aligned on the same lateral face on which the ends of the power connections are disposed;   it also comprises devices protecting the signal connections;   the signal connections are molded onto one of the lateral faces of the module;   it also comprises a signal connector;   it comprises electronic components intended for the electrical supply of the excitation coil of the rotor;   its housing is substantially triangular in shape;   one of the lateral faces of the housing is in the form of an arc of a circle;   the lateral face in the form of an arc of a circle is the face oriented towards the outside diameter of the machine;   it also comprises two electrical connection tracks intended to be connected to a brush holder;   it also comprises a housing for sensors sensing the position of the rotor of the machine;   it also comprises positioning devices for an assembly on the dissipator, the means being situated on the bottom face of the module;   first positioning devices are situated as close as possible to the signal connections;   second positioning devices are positioned as far away as possible from the first positioning devices;   it also comprises orifices for receiving fixing means for fixing the module to the dissipator;   it also comprises support zones to enable it to be fixed to the dissipator by pressing;   it also comprises a metal plate intended to receive at least one substrate on which electronic components are integrated;   it is intended to cooperate with a power interconnection piece, the power interconnection piece being intended to supply the module with power;   the cooperation takes place by means of one end of a power connection configured so as to establish a connection with a power terminal of the power interconnection piece flat on flat;   the cooperation takes place by means of an end of a power connection configured so as to establish a connection with a fixing terminal of the power interconnection piece;   it is intended to cooperate with a signal interconnection piece, the piece being intended to convey control signals intended for the functioning of the machine; and   the cooperation takes place between the signal connections and the associated signal interconnection devices of the signal interconnection piece.       

     A second object of the invention concerns a rotary electrical machine comprising
         a rotor;   a stator provided with a polyphase winding;   a shaft carrying the rotor about a rotation axis;   a bearing to which the stator and the shaft are fixed; and   a dissipator integrated or not in the bearing; the machine being defined by an outside diameter, the machine comprises at least one module according to one of the additional characteristics set out above.   the reversible rotary electrical machine according to the preceding claim comprises:
           a plurality of power electronic modules, each cooperating with a phase of the stator; and   a control and/or control/excitation electronic module, the power electronic and control modules being defined according to one of the additional characteristics set out above.   
               

     Other characteristics and advantages of the present invention will emerge from the following description. This is purely illustrative and must be read with regard to the accompanying drawings, given by way of non-limitative examples. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  depicts the first embodiment of an electronic module according to the invention; 
         FIG. 1B  depicts the module of  FIG. 1A  in a view from below; 
         FIG. 1C  is a view without overmolding of the module of  FIG. 1A ; 
         FIG. 1D  is the view of  FIG. 1C  with hard-wired connections of the electronic components of the electronic module; 
         FIG. 2A  is a first variant of the first embodiment of  FIG. 1A ; 
         FIG. 2B  is a view from below of the module of  FIG. 2A ; 
         FIG. 2C  is the view of  FIG. 2A  with hard-wired connections of the electronic components of the electronic module; 
         FIG. 2D  is a second variant of the first embodiment of  FIG. 2A ; 
         FIG. 3A  shows a second embodiment of an electronic module according to the invention; 
         FIG. 3B  is a view from below of the module of  FIG. 3A ; 
         FIG. 3C  is a view without overmolding of the module of  FIG. 3A ; 
         FIG. 3D  is a variant of the second embodiment of  FIG. 3A ; 
         FIG. 3E  is the view of  FIG. 3D  with hard-wired connections of the electronic components of the electronic module; 
         FIG. 4A  is a third embodiment of the electronic module according to the invention; 
         FIG. 4B  is a view from below of the module of  FIG. 4A ; 
       FIG.  4 B′ is a view similar to that of  FIG. 4B  for an electronic module according to the invention incorporating power electronic components that form two bridge rectifier/inverter arms; 
         FIG. 4C  is a view without overmolding of the module of  FIG. 4A ; 
         FIG. 4D  is a view in section without overmolding of the module of  FIG. 4A  including a support plate; 
         FIG. 4E  is the view of  FIG. 4C  with hard-wired connections of the electronic components of the electronic module; 
       FIG.  4 E′ is a view similar to that of  FIG. 4E  for an electronic module according to the invention incorporating power electronic components that form two bridge rectifier/inverter arms; 
         FIG. 5A  is a variant of the third embodiment of  FIG. 4A ; 
         FIG. 5B  is a view from below of the module of  FIG. 5A ; 
         FIG. 5C  is a first view from above without overmolding of the module of  FIG. 5C ; 
         FIG. 5D  is a second view from below without overmolding of the module of  FIG. 5A ; 
         FIG. 5E  is a third view from above without pre-molding and without overmolding of the module of  FIG. 5A ; 
         FIG. 5F  is a fourth view from below without pre-molding and without overmolding of the module of  FIG. 5B ; 
         FIG. 6  depicts a first embodiment of a dissipator bearing intended to receive a module of  FIGS. 1A and 2A ; 
         FIG. 7  depicts a second embodiment of a dissipator bearing intended to receive a module of  FIG. 3A ; 
         FIG. 8A  depicts a first embodiment of a dissipator intended to receive a module of  FIGS. 4A and 5A ; 
         FIG. 8B  is a view from below of the dissipator of  FIG. 8A ; 
         FIG. 8C  is a view in section of  FIG. 8B ; 
         FIG. 8D  shows an axial air flow and a radial air flow in the dissipator of  FIG. 8B ; 
         FIG. 9A  depicts a first embodiment of a signal interconnection piece intended to be placed on a module of  FIGS. 1A and 2A ; 
         FIG. 9B  is a view from below of the piece of  FIG. 9A ; 
         FIG. 9C  is a view without overmolding of the piece of  FIG. 9A ; 
         FIG. 10A  depicts a second embodiment of a signal interconnection piece intended to be placed on a module of  FIG. 3A ; 
         FIG. 10B  is a view from below of the signal interconnection piece of  FIG. 10A ; 
         FIG. 10C  is a view without overmolding of the signal interconnection piece of  FIG. 10A ; 
         FIG. 11A  depicts a third embodiment of a signal interconnection piece intended to be placed on a module of  FIGS. 4A and 5A ; 
         FIG. 11B  is a view from below of the signal interconnection piece of  FIG. 11A ; 
         FIG. 11C  is another view from above of the signal interconnection piece of  FIG. 11A ; 
         FIG. 11D  is a view without overmolding of the signal interconnection piece of  FIG. 11A ; 
         FIG. 12A  shows a first embodiment of a power interconnection piece intended to be in contact with a module of  FIGS. 1A and 2A  and to be situated above the signal interconnection piece of  FIG. 9A ; 
         FIG. 12B  is a view from below of the piece of  FIG. 12A ; 
         FIG. 12C  is a view without overmolding of the piece of  FIG. 12A ; 
         FIG. 13A  depicts a second embodiment of a power interconnection piece intended to be in contact with a module of  FIG. 3A  and to be situated above the signal interconnection piece of  FIG. 10A ; 
         FIG. 13B  is a view from below of the piece of  FIG. 13A ; 
         FIG. 13C  is a view without overmolding of the piece of  FIG. 13A ; 
         FIG. 14A  shows a third embodiment of a power interconnection piece intended to receive a dissipator of  FIG. 8A ; 
         FIG. 14B  is a view from below of the piece of  FIG. 14A ; 
         FIG. 14C  is a view without overmolding of the piece of  FIG. 14A ; 
         FIG. 14D  is a view of the piece of  FIG. 14A  including a collar; 
         FIG. 14E  is a view of the piece of  FIG. 14D  on a dissipator bearing; 
         FIG. 15A  is a first embodiment of a cover intended to be situated on top of the power piece of  FIG. 12A ; 
         FIG. 15B  is a view from above of the cover of  FIG. 15A ; 
         FIG. 15C  is a side view of the cover of  FIG. 15A ; 
         FIG. 16  is a second embodiment of a cover intended to be situated above the power piece of  FIG. 13 ; 
         FIG. 17A  is a third embodiment of a cover intended to be situated on top of the signal interconnection piece of  FIG. 11A ; 
         FIG. 17B  is a view from above of the cover of  FIG. 17A ; 
         FIG. 18  depicts a mounting of an electronic module of  FIGS. 1A and 2A  on a dissipator bearing; 
         FIG. 19  depicts a mounting of a signal interconnection piece of  FIG. 9  on the dissipator bearing/modules assembly of  FIG. 18 ; 
         FIG. 20  depicts a mounting of the power interconnection part of  FIG. 12A  on the dissipator bearing/module/signal interconnection piece assembly of  FIG. 19 ; 
         FIG. 21  depicts the arrangement of  FIG. 20  with a cover in partial cross-section; 
         FIG. 22  is a complete view of the arrangement according to  FIG. 21  with the cover in place, showing a positioning of the cover with respect to a module; 
         FIG. 23  depicts a mounting of an electronic module of  FIG. 3A  on a dissipator bearing; 
         FIG. 24  depicts a mounting of the signal interconnection part of  FIG. 10A  on the dissipator bearing/modules assembly of  FIG. 23 ; 
         FIG. 25  depicts a mounting of the power interconnection part of  FIG. 12A  on the dissipator bearing/module/signal interconnection piece assembly of  FIG. 24 ; 
         FIG. 26  depicts the arrangement of  FIG. 25  with a cover in partial cross-section; 
         FIG. 27A  depicts a mounting of the modules of  FIG. 4A  on a dissipator; 
         FIG. 27B  depicts a mounting of the power interconnection piece of  FIG. 14A  on a dissipator; 
         FIG. 28  depicts a mounting of the power interconnection piece of  FIG. 14A  on the dissipator/modules assembly of  FIG. 27A ; 
         FIG. 29  depicts a mounting of the signal interconnection piece on the assembly of  FIG. 28 ; 
         FIG. 30A  is an assembling of the assembly of  FIG. 29  on a bearing; 
         FIG. 30B  is a section along a plane X-Y of  FIG. 30A  of the assembled power interconnection piece of  FIG. 14A ; and 
         FIG. 30C  depicts a bearing on which the assembly of  FIG. 29  is assembled. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     It should be noted that, in the remainder of the description, the diameter of a bearing of the machine without fixing lug is defined as the outside diameter of the machine. 
     Electronic Module 
     It should be noted that an electronic module, in the context of the invention, is a set of electronic components that are disposed in a housing and comprises connection elements accessible from the outside for its functioning, these elements making it possible to transmit control and/or power signals. 
       FIG. 1A  depicts a first non-limitative embodiment of an electronic module  10  according to the invention. 
     The electronic module  10  comprises:
         a housing  101 ;   electronic components  102  located in a central zone  1021  covered with a protective gel such as a gel of the silicone or epoxy resin type, and a protective plastic cover;   electrical conductors  103  (B+),  104  (B−);   signal connection elements  106 ; and
           fixing points  108 .   
               

     In addition, the electronic module  10  comprises, as indicated on the view from below in  FIG. 1B :
         means  109  of positioning the electronic module  10  on a dissipator bearing.       

     The various elements of the electronic module  10  are described below. 
     The housing  101  is made from electrically insulating material. Preferably, the housing has a substantially triangular basic shape and therefore has at least three lateral faces and one top face and one bottom face. This shape will make it possible to use a maximum amount of surface area on the cylindrical rear of the machine, and this in an optimum fashion. 
     Moreover, preferentially, one of the faces of the electronic module  10  is an arc of a circle. This is appropriate to the general shape of the machine. 
     Naturally it would be possible to use other shapes, such as a substantially rectangular shape. 
     The electrical conductors  103  (B+),  104  (B−) convey a current coming from the battery through the electronic elements. 
     In a preferential embodiment, the electrical conductors  103 ,  104  are two power connection tracks, the ends of which are disposed on the external periphery of the module. Preferentially, the tracks are made from copper. 
     Thus, unlike an architecture in which the power necessary for each module passes through all the modules or in which an electronic power card is situated in a housing separate from the machine, this configuration has the following advantages:
         this allows a salt spray to flow towards the outside of the machine instead of banking up at the center of the machine, which prevents corrosion of the tracks by the salt spray;   there is less heating in the modules since the power necessary for a module passes only through the module;   the welds on the ends of the tracks are carried out on a single radius, which makes it possible to automate the welding better; and   this also allows balancing of the current in the modules because each module is supplied independently, i.e. they are supplied in parallel.       

     In a first variant of this embodiment, the electrical conductors  103 ,  104  extend in a plane parallel to that along which the block of electronic elements extends. This allows laser welding axial with respect to the axis of the machine. 
     In a second variant, the tracks extend along two planes parallel to each other and parallel to the plane of the block of electronic elements. 
     It should be noted that track means a cropped metal sheet formed from a metal such as copper. 
     The signal connection elements  106 , called signal connections, convey control signals for controlling the electronic components  102 . They thus allow the sending and reception of information necessary for controlling the inverter arm (motor mode) and/or the arm of the bridge rectifier (generator mode). They afford connection with a signal plate (described below). 
     In a first preferential embodiment, these signal connection elements  106  comprise a first series of signal tongues  106   a  and are aligned on one of the lateral faces of the triangular housing of the module. Thus the axes of these signal tongues  106   a  are in the same plane P 1  perpendicular to the bottom face of the module, the plane passing essentially through the rotor rotation axis AX. 
     This alignment makes it possible to carry out linear tongue welding, which limits the time needed for the manufacturing method, called the “process”, and the size. This configuration has the advantage of having, for the signal interconnection piece, a signal track cut in one go, unlike another configuration in which the signal tracks overlap. It will be noted that, if the tongues are offset towards the inside of the module, i.e. if the plane does not pass through the rotation axis, the space for the electronic components  102  is reduced, and otherwise the space for the other modules is reduced. 
     Fixing means  108 , represented here by orifices, are intended to facilitate the holding of the module on the electrical machine by means of studs  113  or screws etc, or any appropriate fixing means. 
     The means  109  of positioning the electronic module  10  on a dissipator bearing or dissipator are here two in number  109   a ,  109   b  as illustrated in  FIG. 1B , which are on the bottom face of the module, close to two opposite edges. In the example, these are pins situated on each side of the electronic components  102 . They are here spaced at a maximum, which limits positioning errors. 
     In addition, preferentially, the electronic module  10  also comprises, as illustrated in  FIG. 2A :
         means  107  of protecting the signal connection element  106 , facilitating the positioning of a cover (described below).       

     In addition, preferentially, the electronic module  10  also comprises, as illustrated in  FIG. 1A :
         a phase track  105  connecting the module to a phase of the stator.       

     In a preferential embodiment, the phase track  105  has an end  105   z  that comprises a hook  105   cr  and makes it possible to connect thereto, by welding, brazing or any other suitable method, a phase wire or phase tongue coming from the stator of the electrical machine. In the example depicted in  FIG. 1A , the end  105   z  is perpendicular to the track, i.e. to the bottom face, and is situated below the plane; it extends downwards. Thus this allows a reduction in the length of the phase wire of the stator and involves a radial weld. In addition, the end  105   z  of the phase track  105  is situated on the external circumference of the module, which facilitates the connection with a phase of the stator. In addition, preferentially, the end  105   z  of the phase track  105  is placed between two electrical conductors  103 ,  104 . 
     This optimizes the “wire bounding” hard-wired electrical connections between the transistor electronic components and the tracks, in particular their length, and this makes it possible to avoid overlapping of tracks. In addition, preferentially, the end of the phase track  105  is situated in line with a phase output of the stator, which facilitates the welding with the phase. 
     In addition, preferentially, according to a first variant of this embodiment, the electronic module  10  is a control module  30  that also comprises, as illustrated in  FIGS. 2A and 2B :
         a third series of signal tongues  106   c  that are aligned on the external periphery of the triangular housing of the module, the periphery coinciding with the outside diameter of the machine. This series of tongues makes it possible to be connected to a signal connector integrated in a cover, and   a second series of signal tongues  106   b  that are aligned parallel to the third series of signal tongues  106   c  and offset towards the inside of the module. This second series of signal tongues  106   b  conveys complementary signals that have not been able to be integrated in the first series of signal tongues  106   a , for example signals SC for a control element of a switch. This enables the two series of signal tongues  106   b  and  106   c  to be cropped on a single occasion. It should be noted that the third series of signal tongues  106   c  is preferentially positioned higher than the second series of signal tongues  106   b  in order to facilitate the welding of a cover to the control module after having carried out the welding of a signal interconnection piece  22 .       

     In other words, the second and third series of signal tongues  106   b ,  106   c  are aligned on the same face on which the ends of the power connections are disposed:
         a housing  112  for stator position sensors.       

     It should be noted that the interconnections between the transistors and the associated tracks are effected by “wire bounding” hard-wired connections as illustrated in  FIG. 2C . In the context of a module with a single transistor per potential, there is one transistor disposed on the electrical conductor  103 , which is connected to the phase track  105  and to the ceramic  1110  of the control element  111 , while a second transistor is disposed on the phase track  105  and is connected to the negative electrical conductor  104  and also to the ceramic  1110 . It should be noted that it would also be possible to have a transistor on the negative electrical conductor  104 . 
     It should be noted that, in this example, there are four transistors, two transistors for the “low side”, indicated LS, and “high side”, indicated HS, of an arm, that is to say two transistors per potential in order to increase the power of the machine. 
     In addition, preferentially, according to a second variant of this embodiment, the electronic module  10  is an excitation module  40 , as illustrated in  FIG. 2D . It comprises electronic components  102 , in particular MOS transistors and diodes, which represent the excitation stage of the rotor of the machine. 
     Thus the electronic modules  10  have, with regard to the arrangement of the electrical conductors  103 ,  104  and their ends forming electrical conductors inside each module and with regard to the arrangement of the signal connection element  106 , a standardized architecture makes it possible to use the modules on different types of electrical machine. This standardization of the architecture makes it possible to replace any electronic module  10  with a module with the same architecture. In addition, this makes it possible to integrate the modules directly on the rear bearing of the machine. In this way the power and control electronics are integrated on the machine directly. The electronics are no longer in an electronic power card in a separate housing. 
     Thus, according to the architecture of an electronic module  10  described previously, it is possible to have power modules  20  ( FIGS. 1A to 1C ), a control module  30  ( FIGS. 2A to 2C ) and an excitation module  40  ( FIG. 2D ). 
     In the case of the power modules  20 , the electronic components  102 , illustrated in  FIG. 1C , comprise for example:
         a set of electronic switches  110  intended to produce a rectifier bridge/inverter arm for a phase of the machine;   control elements  111 , called drivers, associated with the switches; and   a temperature sensor  118  (positioned on a ceramic) for the phase track  105 .       

     The electronic switches  110  can for example be MOSFET-technology transistors that are in the form of packaged components, that is to say presented with a can, or, in order to increase the compactness of the arrangement of the modules and to reduce costs, in the form of bare chips, that is to say without a can. The electronic switches (MOSFETs) or MOS transistors  110  are controlled by the control elements  111 , normally called drivers, on a ceramic  1110  with additional components. Preferentially, the drivers are ASICs. The electronic elements can also be diodes of an arm of a bridge rectifier, since MOS transistors  110  have a better efficiency than diodes. The number of electronic components depends essentially on the constraints of the particular application (three-phase or hexaphase machine for example), the level of power required by the machine, etc. 
     For a three-phase machine, there will preferably be three power modules serving to produce an inverter (one module per phase). More generally, the machine is a polyphase machine (x phases), preferably having one module per phase. 
       FIG. 1D  illustrates the hard-wired connections, normally referred to as “wire bounding”, between the transistors and the electrical conductor  104  and the phase track  105 . It should be noted that, in this example, there exist four MOS transistors  110 , so as to increase the power of the machine. Naturally there may be only two of them. It should be noted that the ceramic  1110  also serves as a support for electronic components but also as interconnection between the transistors and the control element  111 . 
     The control module  30  makes it possible to control the machine and in particular the adjustment of the excitation current by controlling the drivers of the MOS transistors. It also has, as illustrated in  FIG. 2A , an electronic control component  102 CTRL, capacitors  102 CA and a transformer  102 TR for supplying the control element  111  of the power modules. Control signals will thus be sent from the control component  102 CTRL to the control element  111  of the power modules. 
     The excitation module  40  makes it possible to supply the coil of the rotor of the machine, the module comprising in a conventional manner MOS transistors and diodes for determining the current in the rotor. 
     Thus the control module  30  and the excitation module  40  repeat the architecture of the electronic module  10  and in particular the arrangement of the ends of the electrical conductors  103 ,  104  and the signal connection element  106 . 
     According to a variant embodiment, the control module  30  and the excitation module  40  can be replaced by a common excitation and control module. 
     All the modules  20 ,  30  and  40  are mounted on a rear bearing of the rotary electrical machine. 
     In a second non-limitative embodiment, illustrated in  FIG. 3A , the electronic module  10  differs from the first embodiment in that:
         in place of the fixing means  108 , it has support zones  114  for receiving stays belonging to a signal interconnection piece, as will be described below, which makes it possible to omit the fixing studs  113  so that the cost of the parts and assembly are reduced, and this makes it possible to obtain a simpler assembly.       

     The electronic module  10  can be seen in view from below in  FIG. 3B  and in a view without overmolding in  FIG. 3C  for a power module. It should simply be noted in  FIG. 3B  that the module preferably comprises a fixing clip  125  for a plastic cover for a module in order to protect the protective gel for the components. This fixing clip can be replaced by a bonding of the cover or ultrasonic welding for example. 
       FIG. 3D  presents a variant embodiment for a control/excitation module  30 / 40 . It should be noted that having a single module for the control and excitation function makes it possible to save in terms of size. 
       FIG. 3E  presents the “wire bounding” hard-wired connections of this variant. It should be noted that there exists an interconnection between the control ceramic and the excitation ceramic (substrate) produced by a “wire bounding” hard-wired connection to allow transmission of signals between the excitation part and the control part. 
     In the first two embodiments described, preferentially, the ends of the electrical conductors  103 ,  104  are flat and flush on the bottom face of the module. Thus this configuration has the advantage of being able to weld tracks of a power plate (described in detail below) on the ends of tracks of a module by transparency (flat on flat). 
     In a third non-limitative embodiment, illustrated in  FIG. 4A , the electronic module  10  is configured so as to be fixed to a dissipator, itself fixed to the rear bearing of the machine. 
     It differs from the second embodiment in that:
         the end  105   z  of the phase track  105  is perpendicular to the bottom face of the module and projects beyond the housing  101  of the module and its plastic cover, and extends upwards. Thus this allows axial welding and thus prevents being interfered with by the lugs fixing the alternator starter on the engine, whatever the engine of a manufacturer; and this facilitates access to the welding tool;   the end of the electrical conductor  103  (B+) is a folded tongue allowing radial laser welding with a power plate or axial electric welding by electrodes; it extends axially upwards with respect to the housing  101  of the module and projects beyond the housing  101  in order to engage the electrodes, i.e. it is perpendicular to the bottom face of the module; the tongue projects beyond the dissipator  80 . This makes it possible to connect a power interconnection piece  21  with the module from below;   the end of the negative electrical conductor  104  (B−) is no longer a tongue but a hollow cylindrical metal insert allowing electrical connection to a dissipator  80  via the electrical conductor  104  (B−) and a screw  1150  corresponding to the orifice  115 , the screw  1150  making it possible to compress the electrical conductor  104  on the insert and thus to compress the track plus insert on the dissipator  80  so as to effect the earthing of the module, the dissipator  80  being earthed as will be described in detail below;   the positioning pins or recesses  109  situated on the bottom face are positioned differently. A first positioning pin  109   a  is positioned as close as possible to the signal connections element  106 , and preferentially centered on the middle one, in order to reduce the positioning tolerance of the tongues with respect to any clearance that may exist between the second positioning pin  109   b  and the corresponding orifice  609   b  (described in more detail below) of the dissipator bearing. In this way the positioning errors of the tongues with respect to the dissipator are reduced. As illustrated in  FIG. 4B , this first positioning pin  109   a  is situated at the middle of the two end signal tongues  106   a . It should be noted that the first positioning pin  109   a  serves to position the module along the axis X-Y, and the second positioning pin  109   b  serves to orient the module in terms of rotation and is the furthest away from the signal tongues  106   a ; and   one of the protective pins or guides  107  is placed more towards the outside of the module so that there exists a kind of support  119  to make it possible to receive a stay of a signal plate. The pins or guides  107  prevent the signal connection elements  106  bending between the time of the manufacture of the module and its assembly on the machine, and serve as preliminary guidance for a signal interconnection piece (described below).       

     In addition, the electronic module  10  according to this third embodiment also comprises:
         an insert  120  comprising a fixing orifice  115 , the insert  120  allowing earthing of the module, and the fixing orifice  115  being intended to fix the module to a dissipator  80  by means of screws  1150  for example; and       

     means  126  of electrical protection of the end of the electrical conductor  103  (B+) that prevent a short-circuit between the potentials B+(power track of the power interconnection piece) and B−(dissipator mass). 
     A view without overmolding of a power module  20  according to this third embodiment is shown in  FIG. 4C . 
     A view with the “wire bounding” hard-wired connections is shown in  FIG. 4E . 
     Preferentially, each power module  20  comprises a plate  1022  of low resistance and low thermal conductivity, preferentially made from aluminum (the same resistance as the dissipator) or copper. 
     Thus there are:
         the electronic components  102  welded to the metal tracks;   the metal tracks, which are visible on the bottom face of the housing of the module, are bonded to the plate  1022  by an electrically insulating and thermally conductive adhesive, for example a glass-ball adhesive, the adhesive electrically insulating the tracks from each other and the tracks with respect to the outside; and   the plate  1022 , which is placed on the dissipator.       

     The plate  1022  is illustrated in  FIG. 4D  (representation in cross-section along an axis A-A in  FIG. 4C ). It should be noted that this plate can be used in the same way on the other control or excitation modules in the context of visible tracks. 
     The plate thus makes it possible to test the electrical insulation of each module independently before assembly on the dissipator or dissipator bearing. Thus, if there exists a problem of short-circuit due to faulty application of the insulating adhesive, this plate  1022  avoids the scrapping of all the modules mounted on the dissipator. Only the module posing a problem will be disposed of before it is assembled on the dissipator. 
     According to a variant of this third embodiment, the electronic module  10  comprises, as illustrated in  FIG. 5A :
         a signal connector  116 ;   a screw  117   a  affording electrical contact between two tracks  117   b  (+EX, −EX) of a brush holder  50  and the electronic module  10 ; and   a screw  117   c  for mechanical holding on the dissipator  80  and making it possible to withstand the mechanical forces of the signal connector  116 .       

     More particularly it is the control module  30  or the control/excitation module that comprises the signal connector  116  and the screw  117   a . It should be noted that the brush holder is here in a single piece with the control module  30 . Indeed it is molded on with the control module  30 . 
     The presence of the signal connector  116  has the advantage of:
         eliminating welds making it possible to effect electrical connections between the cover and the modules, compared with the first embodiment;   avoiding problems of welding and impermeability; and   saving time in the manufacturing process.       

     There therefore no longer exist any external signal tongues  106   c  as in the first or second embodiments, which makes it possible to reduce the material of the tracks  117   b  (those in the cover) as will be seen subsequently. 
       FIG. 5B  is a view from below of the control module  30  according to this third embodiment. 
     As can be seen, the first positioning pin  109   a  is as close as possible to the two series of signal tongues  106   a  and  106   b  in order to limit any errors in positioning of the tongues with respect to the dissipator. 
     In addition there can also be seen:
         a metal plate  121  fixed by the screw  1150 , the plate preferentially being made from aluminum and thus being connected to the dissipator mass via the screw  1150 , the plate comprising substrates  123  of the ceramic type, on which electronic components are integrated; and   position sensors  122  for giving the position of the stator of the electrical machine.       

       FIG. 5C  is a view from above of the control/excitation module without overmolding, without the signal connector  116  and without the brush holder  50 .  FIG. 5D  shows the view from below. 
       FIG. 5E  is a first view without pre-molding and without overmolding of the tracks  117   b  of the control/excitation module in which there can in particular be seen:
         substrates  123  comprising the electronic components for controlling the machine; and   an excitation part  124  comprising the electronic components for excitation of the machine via the brush holder  50 .       

     The tracks of the module can also be seen in the following  FIG. 5F  without pre-molding and without the plastic overmolding in a view from below. 
     It should be noted that the pre-molding is an operation that takes place before the overmolding and that makes it possible to hold certain elements in position, such as the signal connection element  106  for example. 
     It should be noted that, in all the embodiments, the electronic components  102 , in particular the MOS transistors  110 , are mounted on the power connections, namely here the positive electrical conductor  103  and the phase track  105 . 
     Preferentially, in all the embodiments presented above, the power tracks of the modules are visible on the bottom face of the modules. It is thus possible to isolate them electrically from the dissipator or dissipator bearing by means of adhesive in place of the plastic of the housing  101 . The use of adhesive in place of the plastic of the housing  101  makes it possible to have a lesser thickness under the modules (approximately 0.2 mm in a non-limitative example) and to have a lower thermal resistance than plastic so as to have better dissipation in the dissipator bearing or dissipator. 
     It should be noted that, in all the embodiments presented above, it is of course possible to include or not the signal connector  116  in the control module or control/excitation module if so desired. If it is not included, it will be in the cover. 
     It should be noted that the electronic module according to all the embodiments presented above has the following additional advantages:
         it uses bare chips for the electronic components instead of so-called packaged standard components, so as to reduce the size;   it includes the elements for controlling the MOS transistors, referred to as drivers;   a module is configured in order to be perfectly integrated on the dissipator or dissipator bearing so that:   it does not block the axis of the bearing in which the shaft of the rotor is introduced;   there exists an axial cooling with the attached dissipator (not integrated);   all the ends of the power and signal tracks are outside the circumference of the dissipator or dissipator bearing, which facilitates the connections to be established, unlike the case where they are inside the circumference, so as to be accessible and so that there exists more space available on the outside diameter than inside for the ends;   a module is preferentially configured for a single phase so that:       

     the hook of the module is opposite the natural exit of a stator phase;
         there is one module per phase, adaptation to the space available on the dissipator or dissipator bearing is easier compared with a single module comprising three phase tracks, and this in an optimum manner;   the definition of the module makes it possible to have a power, control and excitation module with the same architecture; and       

     in the event of failure of welding of one of the transistors, it avoids too much scrap compared with a single module for the three phases of the stator. 
     It should be noted that it is also possible to provide a single overmolding for all the power modules  20 , the control module  30  and the excitation module  40  or control/excitation module  30 / 40 . 
     At this moment there would be a single module that would comprise the power, the control and the excitation, the module then comprising three phase tracks. 
     Other Elements 
     An electronic module  10  cooperates with the following elements:
         a dissipator bearing  60  (dissipator integrated in the bearing, i.e. in a single piece with the bearing), or a dissipator  80  (dissipator not integrated in the bearing, i.e. attached to the bearing)   a signal interconnection piece  22 ;   a power interconnection piece  21 ; and   a cover  70 .       

     These elements are described below. 
     Dissipator Bearing 
     The function of a dissipator bearing is to discharge the heat from the electronic modules. 
     The rear dissipator bearing  60 , shown in  FIG. 6 , comprises, according to a first non-limitative embodiment:
         a plurality of positioning orifices  609 , preferentially two orifices  609   a ,  609   b  per module, in order to position the modules on the bearing  60 , the orifices  609   a  and  609   b  being situated on the same diameter, i.e. in the example illustrated ten orifices;   a plurality of fixing orifices  608  for receiving the three fixing studs  113  of each module on which the power plate will be positioned, that is to say in the example illustrated fifteen orifices;       

     air inlets  601  comprising fins  606 ; air outlets  602  comprising fins  606 ;
         various recesses referenced  603  for the rotor shaft of the rotary electrical machine,  604  for the Hall effect sensors making it possible to know the rotor position, and  605  for a brush holder  50 ; and       

     positioning orifices  610  for positioning a signal plate, here two positioning orifices  610   a  and  610   b  that are distributed on each side of the diameter of the dissipator bearing  60 . Preferentially one of the positioning orifices  610   a ,  610   b  is the reference control for the dissipator bearing  60 , and thus an already existing orifice is used. 
     It should be noted that  FIG. 6  shows the locations of the various modules. Thus the locations marked P, C and E receive respectively the three power modules  20 , the control module  30  and finally the excitation module  40 . 
     According to a second non-limitative preferential embodiment illustrated in  FIG. 7 , the dissipator bearing  60  comprises:
         a plurality of fixing orifices, here four,  681 ,  682 ,  683  and  684  for receiving four studs holding the signal plate;   a fixing orifice  685  for receiving a fixing screw of a brush holder  50 , there is no stud, which avoids reducing the cross-section of the track B+of a power plate;   the following same elements as the first embodiment:
           air inlets  601  comprising fins  66 ;   
           air outlets  602  comprising fins  606 ;
           various recesses  603 ,  604  and  605 ; and   the positioning orifices  610   a  and  610   b  for the signal plate.   
               

     It will be noted that the control and excitation functions have been combined in a single control/excitation module. Moreover, the location C/E and P respectively of the control/excitation module and the power module  20  in  FIG. 7  will be noted. 
     It will also be noted that the fins  606  can, as known to persons skilled in the art, be replaced by a liquid cooling circuit for the two embodiments of the dissipator bearing described above. 
     Dissipator 
     The function of the dissipator  80  is to discharge the heat from the electronic modules. 
     The dissipator  80  as illustrated in plan view in  FIG. 8A  is independent of the rear bearing of the rotary machine. 
     It comprises, according to a non-limitative preferential embodiment:
         a base plate  801  preferentially made from cast aluminum; and   fixing orifices  806  on the rear bearing of the machine, here four, in order to receive fixing studs of a signal plate;   an electrical connection orifice  805  for connecting the dissipator to earth via the power interconnection piece  21  by means of a nut;   fixing orifices  804  for fixing the modules, here four, and connecting them to the dissipator earth via an insert;   a fixing orifice  807  for fixing a signal connector of the control/excitation module via an insert;   mechanical positioning orifices  808  for positioning a power interconnection piece  21 , here two distributed on each side of the diameter of the dissipator  60 ;   recesses  809  on the circumference for receiving electrical protection means, here three, for the positive track (B+) of the power interconnection piece  21 ;   positioning orifices  810  for the modules, here two per module, that is to say eight orifices;   mechanical positioning orifices  811  for positioning a signal interconnection piece  22 , here two distributed on each side of the diameter of the dissipator  60 ; and   recesses  812  for inserting phase housings of a power plate as will be seen in detail below. There therefore exist three of them here,   recesses  815 ,  816 ,  817  for receiving respectively a brush holder, position sensors and the rotor shaft.       

     The locations C/E and P respectively of the control/excitation module and the power modules  20  will be noted. 
       FIG. 8B  shows a plan view of the dissipator. 
     It can be seen that the dissipator also comprises:
         blocks of cooling fins  802  intended to substantially increase the heat dissipation of the power modules  20 , the blocks being situated on the bottom face in the position of use of the base plate  801 ;   support zones  814  for receiving force stays for the power interconnection piece that make it possible to withstand the engine vibrations; and   a protrusion  813  that guides the air from the radial inlet of the machine towards the inside of the machine and thus prevents the air stagnating at the dissipator. This is also the case for the axial air. It is guided towards the inside of the machine. It should be noted that the fins at this level pass through the protrusion  813 . A section X-X of the protrusion can be seen in  FIG. 8C .       

     In addition, it should be noted that the base plate  801  is configured firstly so as to be able to be assembled in a sandwich between a power interconnection plate and the modules, and a signal interconnection plate, and secondly to leave at the center a sufficiently large passage for the cooling air of the electrical machine. 
     As indicated in  FIG. 8D , a first flow of the air will enter the machine in this way axially FA. This has the advantage of increasing the speed of the air and thus reducing the pressure drops compared with a radial flow (the case of the first and second embodiments of the dissipator bearing described previously). 
     In this way, a looping of air heated by the machine between an output and an input of the dissipator bearing is avoided (for the air incoming axially) and thus re-injecting hot air into the machine is avoided. 
     More particularly, it is the recess  817  that is configured so as to allow air to pass around the rotor shaft and is therefore wider than the diameter of the rotor shaft or, to be more precise, of the shaft collector protector. 
     In this way the standard cooling applied to a conventional alternator is approached. 
     Moreover, the axial air flow is guided by the first slope  813 P 1  of the protrusion  813  of the dissipator so that there is no stagnant air on the bottom face of the dissipator level with the fins. 
     In addition, by virtue of the positioning of the dissipator  80  described, there is also a second air flow that is radial between the dissipator  80  and the power interconnection piece  21 . This can also be seen in  FIG. 8D . This radial air FR enters through the dissipator  80  and leaves again through the fins  606  in the bearing  60 . This radial air flow increases the output of air and therefore improves the cooling of the machine, the latter thus being more efficient than if there were only an axial air flow. 
     In addition, by virtue of the protrusion  813  situated level with the fins, this radial air flow does not stagnate since it is guided by the second slope  813 P 2  of the protrusion  813  towards the inside of the machine. 
     It should be noted that these radial FR and axial FA air flows are accelerated by the fan of the machine, which gives rise to a better cooling of the machine plus the electronics because in particular of the arrangement of the dissipator as described above. 
     Signal Interconnection Plate 
     The signal interconnection piece  22  is intended to convey various signals necessary for the functioning of the modules and, thereby, for the correct functioning of the rotary electrical machine. Such signals are for example:
         a signal for the operating mode of the electrical machine, for example motor or generator;   a signal indicating the temperature of the modules;   a signal sending back a fault detected on the modules;   a control signal for the switches of the MOSs etc.       

     These signals are conveyed between the power modules  20  and the control module  30 . 
       FIGS. 9A to 9C  show a first non-limitative embodiment of the signal interconnection piece  22 . 
     It comprises:
         a base plate  220  made from insulating material, preferentially made from plastic, and preferentially substantially cylindrical, which molds on metal signal tracks TS;   a central recess  223  for lightening the plate in terms of material;   recesses  221   a  for leaving visible metal tracks TS, the tracks comprising interconnection orifices  2210 , here five orifices, the axes of which are disposed in a plane P 2  (shown in  FIG. 9C ) perpendicular to the surface of the plate and passing substantially through the rotor rotation axis AX, the orifices being intended to receive the signal connection element  106  of an electronic module with a view to being connected electrically;   a connection recess  221   b  for leaving visible metal tracks TS, the tracks comprising interconnection orifices  2211 , disposed at the external periphery of the signal interconnection piece  22 , the orifices being intended to receive the signal connection element  106  of a control module, here three orifices; and   fixing lugs  222  intended to be inserted in one of the three holding studs  113  of an electronic module, and intended to receive a fixing nut, the fixing lugs holding the signal interconnection piece  22  on the modules, by means of the studs, first lugs  222   a  being disposed on the outside diameter of the plate and projecting beyond the plate, and second lugs  222   b  being disposed on the internal diameter of the plate and also attenuating vibrations of the plate.       

     It should be noted that the recesses  221   a  and  221   b  can be protected subsequently against the external environment by a resin for example. 
     It should also be noted that the base plate  220  comprises orifices  2210   z ,  2211   z  opposite the orifices of the metal tracks TS, as illustrated in  FIG. 9B . 
     The signal interconnection piece  22  also comprises:
         positioning pins or studs  224  for assembly on a dissipator bearing  60 , here two as illustrated on the view from below in  FIG. 9B ; and   metal signal tracks TS configured to adapt to the shape of the plate and to the position of the signal connection element  106  of the modules, and comprising interconnection orifices  2210 ,  2211  as illustrated in  FIG. 9C . The tracks are preferentially in the same plane. Moreover, they are preferentially configured in the form of arcs of a circle essentially concentric with respect to the rotor rotation axis.       

       FIGS. 10A to 10C  depict a second preferential embodiment of the signal interconnection piece  22 . 
     This signal interconnection piece  22  comprises:
         in place of the fixing lugs of the first mode, stays  225  for pressing the modules against a dissipator bearing, first stays  225   a  and second stays  225   b  being positioned respectively on the external or internal periphery of the plate, here nine in total; there are thus three support points on each module;   in place of the three recesses per module, only three support inserts  226  intended to receive three studs  226   g , for fixing to the dissipator bearing  60 ; and   a metal insert  226  for receiving a screw  226   v  for fixing the plate to the dissipator bearing. This screw avoids reducing the cross-section of the positive power tracks (B+) of the power interconnection piece  21  (described below).       

     These four inserts also prevent flow of the overmolding plastic. It will therefore also be possible to use them for the first embodiment. 
     The signal interconnection piece  22  also comprises:
         at least one fixing housing or holding clip  227  for fixing the power interconnection piece  21  and receiving a fixing clip or lug ( 218 ), here two housings; and   an additional central recess  228  for receiving a brush holder.       

     In a first variant embodiment of this mode, the plate also comprises separators  229  for signal connection element  106  so as to prevent short-circuits between the tongues, short-circuits due in particular to salt spray. In this way the length of the electrical path between the tongues is increased. 
     In another variant, the plate does not have any separators. At this moment, in order to isolate the tongues from each other, seals are provides that surround the signal connection element  106  on the modules themselves. Subsequently the signal interconnection piece  22  will compress these seals. 
     It should be noted that these two variants apply to the two embodiments of the electronic module described above and to the third embodiment, which will be described later. 
     In  FIG. 10C , it is possible to see the concentric metal tracks of the signal interconnection piece  22 . The metal tracks are configured to adapt to the position of the signal connection element  106  of the modules, and preferentially to the shape of the plate, and in addition to pass round the four inserts  226 . They are preferentially configured in the form of arcs of a circle essentially concentric with respect to the rotor rotation axis. 
     It should be noted that the stays  225  are, non-limitatively, cylindrical in shape. This shape has a sharp edge  2250 . 
     In addition, it should be noted that the signal interconnection piece  22  according to this second embodiment has the following same elements as the plate according to the first mode:
         the base plate  220 ;   the recesses  221   a  and  221   b;      the central recess  223  intended to receive here a rotor shaft;   the positioning pins  224 ; and   the metal tracks TS with the orifices  2210  and  2211 .       

     It should be noted that, for the first and second embodiments described above, the signal tracks are preferentially configured inside the diameter on which the power terminals (described in detail below) are produced. This enables the power interconnection piece  21  (described below) to fit on top of the signal interconnection piece  22 . Thus assembly is facilitated and the signal tracks do not interfere with the power tracks. 
       FIGS. 11A to 11D  depict a third non-limitative embodiment of the signal interconnection piece  22 . 
     It differs from the second embodiment in that:
         it no longer has any holding clips  227  for positioning the power interconnection piece  21  since in this embodiment the power interconnection piece  21  is situated below the signal interconnection piece  22 , as will be seen in detail below; and   the stays  225   a  and  225   b  have a different shape. They have a shape that no longer comprises any sharp edge, which prevents the stresses undergone by the plastic being concentrated on the sharp edges. In this way the risk of breaking the stays is reduced.       

     The signal plate  32  also comprises:
         hollowed-out protuberances  230  for pre-positioning the plate on the modules. Here there exist two protuberances. They serve in particular for pre-guidance during the process assembly. This, thus, makes it possible to subsequently fix the positioning pins  224  of the signal interconnection piece  22  in the dissipator  80 . It will thus be possible to position the signal interconnection piece  22  before the assembly of the signal connection element  106 ; and   housings  231  for housing therein filtering capacitors. These capacitors will be connected to the electronic modules. The housings afford good mechanical strength for the capacitors. Resin will be deposited in the housings.       

     Moreover, it should be noted that the signal interconnection piece  22  according to this third embodiment has the following same elements as the plate according to the second embodiment:
         the base plate  220 ;   the recesses  221   a  and  221   b;      the central recess  223 ;   the additional central recess  228  for the brush holder;   the four inserts  226 ;   the positioning pins  224 ; and   the metal tracks TS with the orifices  2210  and  2211 .       

     According to a first variant of this embodiment, the orifices  2210  and  2211  are configured so as to effect a tin weld between the orifices and the corresponding signal connection element  106 . These are therefore holes with a bevel as illustrated in  FIG. 11A  and in  FIG. 11B  in view from below. 
     According to a second variant of this embodiment, the orifices  2210  and  2211  are configured so as to effect a laser weld between the orifices and the corresponding signal connection element  106 . These are therefore folded micro-tongues as illustrated in  FIG. 11C . 
     In  FIG. 11D , the metal tracks of the signal interconnection piece  22  can be seen. The metal tracks are configured so as to adapt to the position of the signal connection element  106  of the modules, and preferentially to the shape of the plate, and in addition to pass round the four inserts  226 . They are preferentially configured in the form of arcs of a circle essentially concentric with respect to the rotor rotation axis. 
     Thus, unlike an electronic card for fulfilling the signal function, such a signal plate has the advantages of:
         withstanding high temperatures, for example 260° C., unlike a conventional PCB electronic card, such a PCB card being composed of copper tracks with a polymer insulator, the copper tracks not withstanding high temperatures;   being able to be centered above the electronic modules  10 ;   comprising metal tracks not necessarily made from copper. This is because, having regard to the relatively low power conveyed by these tracks, a material with a low electrical resistance is not necessarily required. Thus the tracks can for example, non-limitatively, be made from steel;   be as close as possible to the modules, which avoids having signal tongues for the excessively long modules and thus avoiding problems of plugging in; and   by virtue of the metal tracks, which do not overlap, a track cutting is achieved in one go, a fine thickness of the plate is obtained, and therefore a saving in axial size of the whole of the machine, and a facilitated manufacture of the signal interconnection plate.       

     It should be noted that, naturally, in all the embodiments presented above, it is also possible to provide, instead of the interconnection orifices  2210 ,  2211 , other interconnection means such as folded tongues for example. 
     Power Interconnection Plate 
     The power interconnection piece  21  makes it possible to distribute the power between the modules  20 ,  30 ,  40  from outside (in particular the vehicle battery). 
     This piece is independent of the electronic modules, which makes it possible to supply each module with current independently and thus avoid the heating of the modules relating to the passage of the current intended for one module in all the modules. Thus, according to the configuration of this piece and the associated modules, there is no flow of current between the three power modules. 
     The power interconnection piece  21  is, in the most simple case, in the form of a plate produced from an electrically insulating material, preferably plastic. 
     In a first non-limitative embodiment, illustrated in  FIGS. 12A to 12C , it comprises:
         a central recess  210  for lightening the plate in terms of material;   power interconnection tracks  211  (−BATT),  212  (+BATT);   negative  2110  and positive  2120  power terminals issuing from the respective power interconnection tracks  211 ,  212 ;   a plastic overmolding  213  on the power interconnection tracks  211  and  212 ;   a first recess  214   a;      a second recess  214   b ; and   fixing lugs  215 .       

     The elements of the power interconnection plate are described in detail below. 
     The power interconnection tracks  211 ,  212  are disposed at least on one face of the plate. These are tracks made from a metal with low resistance, preferably copper, which are overmolded in the plastics material of the power interconnection piece  21 . 
     They can be produced in the form of a flat strips clipped, riveted, adhesively bonded or fixed in any other suitable manner to the plastic plate. 
     According to a preferential embodiment, the power interconnection tracks  211 ,  212  are interleaved (the power interconnection track  211  is surrounded by the power interconnection track  212 ) and concentric and on the same plane. In this case, the negative power terminals  2110  are folded so as not to interfere with the positive power interconnection track  212  (+BATT). In this way, it is possible to optimize the location of the recesses  214   a ,  214   b  in order to orient a cover according to the requirements of a customer connector making the connection of the machine with the outside. The power interconnection tracks  211  and  212  are not superimposed so as to allow electrical connection with the tracks of such a cover, the zone comprising the recesses  214   a  and  214   b.    
     According to a second embodiment, the power interconnection tracks  211 ,  212  can be superimposed on one another. This is beneficial to the radial size. 
     Finally, it should be noted that each of the power interconnection tracks  211 ,  212  comprises a hole  217   a ,  217   b  making it possible to position the track in terms of x, y in a mould, the latter making it possible to carry out the plastic overmolding  213 . 
     The power interconnection tracks  211 ,  212  have respectively negative power terminals  2110  (−BATT) in an L shape, and positive terminals  2120  (+BATT). The terminals extend radially towards the external periphery of the power interconnection piece  21 . These terminals have curved free ends. The precise dimensions and position of the terminals  2110 ,  2120  are determined so as to enable them to be positioned above the ends of the electrical conductors  104 ,  103  of each of the modules in order to be able to be connected to the tracks by means of welding, brazing or weld-brazing for example. This configuration of the power terminals (in an L shape and having ends curved by bending) on the outside diameter thus facilitates the assembly with the modules. These terminals thus make it possible to obtain an electrical connection with the corresponding electrical conductors  103 ,  104  of the electronic modules  10  so that the electrical power is distributed in each of the modules. It will be noted that the positive power interconnection track  212  overlaps the negative power terminals  2110 . 
     The overmolding  213  comprises a first recess  214   a  for an electrical connection of the power interconnection track  211 , preferably by laser welding, with a cover to the battery, and a second recess  214   b  in the overmolding for an electrical connection of the power interconnection track  212 , preferably by laser welding, with a cover to the battery. 
     Moreover, the overmolding  213  comprises assembly recesses  216  enabling an assembly tool to pass through the plate and assemble the rear dissipator bearing with a front bearing. 
     It should be noted that the ends of the power terminals  2110  and  2120  are not overmolded so that the ends can bear on the ends of the electrical conductors  104 ,  103  of the modules. Preferentially, the whole of the power terminal piece is not overmolded so that assembly on the ends of the tracks is facilitated. This is because this affords more bending in such an assembly. 
     The lugs  215  extend substantially radially over the external periphery of the interconnection plate. Each of the lugs  215  is provided with an orifice making it possible to pass therein, when the various modules and the other elements of the arrangement are assembled, fixing means such as threaded rods or bolts or studs or any other suitable fixing element. 
     In a second non-limitative embodiment, illustrated in  FIGS. 13A to 13C , the power interconnection piece  21  comprises:
         a supplementary central recess  2101 ;   at least one fixing clip or lug  218 ;   inserts  219   a ,  219   b  for receiving holding studs;   a mechanical stop  2112 ;   at least one support pin  2113 ; and   an orifice  219   c.          

     The elements of the power interconnection plate are described in detail below. 
     The supplementary central recess  2101  allows the insertion of the brush holder with its protector. In this case, the brush cage protector is an independent piece assembled on the brush holder, and the brush holder may be removable with respect to the control/excitation module, which facilitates maintenance of the machine in particular in a replacement context, that is to say when the brushes (and therefore the brush holder) are changed when they are worn. Thus, instead of changing all the electronics (the modules and the two plates), only the brush holder will be changed (if the electronics are not faulty). 
     The fixing clips or lugs  218  enable the power interconnection piece  21  to be held mechanically on the signal interconnection piece  22 , here three. 
     The inserts  219   a  and  219   b  for receiving the holding studs, here two in total, and for connecting the power interconnection tracks  211 ,  212  to a cover  70 . The two inserts  219   a ,  219   b  make it possible to gain access to the power tracks so that an overmolding  213  can be effected on the tracks as illustrated in  FIG. 13A . These two inserts thus allow mechanical holding of the plate  1  and an electrical connection. 
     The last orifice  219   c  permits solely mechanical holding of the power interconnection piece  21  by means of a stud. 
     The mechanical stop  2112  makes it possible to stop the power interconnection piece  21  in translation when it is assembled. It bears, for example, on the control/excitation module. In addition this stop has a shorter length than the power terminals  2110  and  2120  of the power tracks so that the terminals bear on the tracks of the corresponding modules before the stop bears on the control module. The stop is disposed on the outside diameter of the plate and projects beyond this plate. 
     The at least one support pin  2113 , here two, enable the power interconnection piece  21  to bear on the dissipator bearing during assembly. 
     The power interconnection piece  21  comprises, as described in the first embodiment:
         the central recess  210 ;   the power interconnection tracks  211 ,  212 ;   the negative  2110  and positive  2120  power terminals; and   the overmolding  213 .       

     It should be noted that the overmolding  213  comprises here a recess  2130  for lightening the plastics material, the recess being possible since no facing power tracks exist. In the same way as in the first embodiment, the power terminals  2110  and  2120  are not overmolded. 
     The power interconnection tracks  211  and  212  are shown in  FIG. 13C . 
     In addition, according to the first and second embodiments:
         the power interconnection piece  21  can also integrate passive filtering components  2114  shown in  FIG. 13B , for example capacitors connected between the power interconnection tracks  211  (−BATT),  212  (+BATT) via micro-tongues  21140   a  and  21140   b . This makes it possible for example to filter the voltage of the on-board system of the motor vehicle and to filter in particular the oscillations due to the electrical conversion components, MOSs, diodes, etc.;   preferentially, the ends of the power tracks are flat and flush on the surface of the module. Thus the advantage of this configuration is being able to weld tracks on a power plate (described in detail below) to the ends of the tracks of a module by flat-on-flat transparency;   the power interconnection piece  21  can also integrate a brush cage protector (not shown) that makes the brush holder impervious. This gives one part less to assemble. The brush holder allows the supply of the excitation current issuing from the excitation module to the rotor via brushes. The protector then comprises positioning guides that will make it possible to position the protector opposite the brush holder;   preferentially, the positive terminals  2120  are rigid lugs defining a reference support plane for the power piece on the corresponding tracks of the modules; and   preferentially, the negative power terminals  2110  are flexible lugs for taking into account the assembly tolerances. Thus, when the modules and the plate are assembled, this will make it possible to deform the tracks of the power plate before welding by transparency. This thus facilitates putting the power interconnection tracks in contact with the corresponding tracks of the modules. It will be possible to use this flexibility also for the first embodiment, also for the third embodiment described below (although this is not necessary).       

       FIGS. 14A to 14E  show a third non-limitative embodiment of the power interconnection piece  21 . 
     The power interconnection piece  21  comprises:
         inserts  210   d  for establishing a mechanical connection with the rear bearing of the machine;   stator phase protection means  211   d;      means  212   d  of positioning on the rear bearing of the machine;   force stays  213   d;      means  214   d  of positioning the plate in the dissipator  80 ;   a fixing terminal  215   d  for fixing the plate to the dissipator  80 ;   an electrical insert  216   d;      a power connector  219   d;      positive  221   d  (B+) and negative  222   d  (B−) tracks molded on in plastic;   positive power terminals  217   d  issuing from the positive track B+;   means  218   d  of protecting the positive power terminals  217   d;      a terminal  220   d  for mechanical connection to a client power connector (not shown) connected to the battery; and   a mechanical connection orifice  220   e  connected to the connection terminal  220   d.          

     The elements of the power interconnection plate are described in detail below. 
     The inserts  210   d  for establishing a mechanical connection with the rear bearing of the machine, by means of screws for example, here four in total:
         the stator phase protection means  211   d  are situated on the outside diameter of the plate and project beyond the plane of the plate, the means preventing contact between a stator phase and the dissipator mass or bearing mass in particular;   the means  212   d  of positioning on the rear bearing of the machine, the means being here a positioning pin, extend on the bottom face of the plate, the pin advantageously being positioned in an oblong hole that is the machining reference orifice of the bearing;   the force stays  213   d  allow downward axial deformation of the power plate in order to avoid vibration problems, the stays preferentially having a greater height than the inserts  210   d  in order to be sure of deforming the plate, the stays extending over the top face of the plate;   the means  214   d  of positioning the plate in the dissipator  80 , here two, extend over the top face of the plate;   the fixing terminal  215   d  makes it possible to fix the plate to the dissipator  80  by means of a nut, and is connected to the negative power track B−, which effects an earthing of the dissipator;   the electrical insert  216   d  is intended to be assembled with the terminal  215   d  on the track  222   d , the track thus being sandwiched by the insert and the terminal, which thus avoids difficult welding to be performed between the dissipator, which is preferentially made from cast aluminum, and the copper power track;   the power connector  219   d  comprises a negative track B− and a positive track B+;   the power terminals  217   d  issuing from a positive track B+are here in an L shape and have an axial tongue, i.e. perpendicular to the plane of the power interconnection piece  21  and projecting beyond the plane upwards; the terminals are not overmolded to allow connection with the end of the positive electrical conductor  103  (B+) of an electronic module, the terminals extending towards the external periphery of the signal interconnection piece  22 ;   the means  218   d  of protecting the positive power terminals  217   d  protect against short-circuits and salt spray in particular;   the positive  221   d  (B+) and negative  222   d  (B−) tracks are molded on in plastic  213  for example, tracks that can be seen in  FIG. 14C . The tracks are visible on the power connector  219   d , which allows the fitting of the client power connector to make the electrical connections between the connector and the tracks;   the terminal  220   d  connecting to the client connector connected to the battery, the terminal making it possible to effect a pressing between the tracks  221   d  and  222   d  and the tracks of the client power connector so that the current can be established correctly between the battery and the machine; and   a mechanical connection orifice  220   e  for a screw, thus avoiding the transmission of the mechanical stresses on overmolding when the client power connector is fixed to the connecting terminal  220   d.          

     Preferentially, in a variant embodiment, as depicted in  FIG. 14E , the overmolding  213  of the power interconnection piece  21  covers the air outlet openings of the bearing (as far as the outside diameter of the bearing) so as to guide the discharged air in order to reduce a radial looping back of the air towards the inside of the machine. Thus the overmolding comprises a covering collar  213   z  shown in  FIG. 14E . 
     Thus the power plate has the advantages of:
         having a single track without overlap, the track making it possible to effect easier molding and positioning;   being fixed under the dissipator  80  and therefore being separated by a mass from the signal interconnection piece  22 , so that the power signal B+does not interfere with the signals from the signal interconnection piece  22 ;   a saving in axial size since the power interconnection piece  21  is positioned in the space necessary for the fins of the dissipator; and       

     enabling the dissipator to be an isolated mass (with respect to that of the bearing) or not, and therefore a different mass from that of the bearing, thus avoiding interference of the on-board system during starting in particular. 
     It will be noted that, by virtue of the presence of the power interconnection piece  21 , there is a large cross-section of copper for conveying the power necessary to the functioning of the machine (150 A in alternator mode, 600 A on starting) unlike a solution in which the power tracks are integrated in a band also comprising the electronic power modules. 
     Cover 
     According to a first non-limitative embodiment, the cover  70  as illustrated in  FIGS. 15A to 15C  comprises:
         positive  71  (B+) and negative  72  (B−) power tracks;   two openings  74  for effecting welding of the power tracks  71 ,  72  with the corresponding tracks of the power interconnection piece  21 ;   signal tracks  75  affording a connection between the modules and signal connections  76 ;   signal connections  76 ;   grooves or orifices  77  for positive location; and   fixing orifices for fixing screws or nuts  78  for example.       

     The elements of the cover are described in detail below. 
     The power tracks  71 ,  72  are intended to electrically connect the power interconnection tracks  212 ,  211  of the power interconnection piece  21  providing the connection between the client power connector of the motor vehicle. The power tracks  71 ,  72  are molded on in the cover  70  and laser welded to the two power interconnection tracks  212 ,  211  of the power interconnection piece  21 . The electrical connections are made between these two elements, for example through the opening  74  provided for this purpose. The electrical connections can be made by welding, in particular by laser welding or weld-brazing, as well as by brazing or by mechanical contact. In the latter case, the mechanical contact is obtained for example by fixing screws for the cover  70  exerting a pressure on the tracks. 
     The signal connections  76  afford a dialogue with the other electronic boxes of the vehicle. These connections comprise signal tracks  75  integrated in the cover  70  and connected on the one hand to the control module  30  and at the other end to the client signal connector (not shown). The client signal connector comprises a cable for connection to a control means such as for example a computer controlling various functions of the vehicles such as for example the management of the rotary electrical machine according to its generator or motor functions. 
     The grooves or orifices for positive location  77  make it possible to position the cover  70  correctly on the guides  107  of the control module  30 . The grooves or orifices thus engage with guides  107  of the control module  30 . 
     According to a second non-limitative preferential embodiment, illustrated in  FIG. 16 , the cover comprises:
         openings  79  intended to receive fixing means such as studs in place of screws.       

     It also comprises the following elements described in the first embodiment:
         the power tracks  71 ,  72 ;   the element  73  for connection to the on-board system;   the two openings  74 ;   the signal track  75 ;   the signal connections  76 ; and   the grooves or orifices  77  for positive location.       

     It should be noted that the cover  70  as described in the two embodiments is intended to be a part specific to each client because of the specific location and the type of client connector or connectors used. 
     According to a third non-limitative preferential embodiment, illustrated in  FIGS. 17A and 17B , the cover is a simple cover that comprises solely fixing clips  791  for the cover fitting on studs  226   g  of the signal interconnection piece  22  fixing the assembly. It no longer comprises any track or connector. There is only plastics material. 
     After having seen all the elements that cooperate with the electronic modules, we describe below their assembly. 
     As will be seen in detail below, the electronic modules are fixed to the rear bearing of the machine in several ways:
         either on the bearing directly (dissipator bearing with fins or water integrating or not heat pipes); or   on a non-integrated dissipator (with fins or water integrating or not heat pipes).
 
1) 1 st  Method of Assembly or Arrangement
       

     According to a first method of assembling the modules, an electronic module interfaces with the following elements:
         a dissipator bearing  60 ;   a signal interconnection piece  22  according to the first or second embodiments;   a power interconnection piece  21  according to the first or second embodiments; and   a cover  70  according to the first or second embodiments.       

     Thus the first method of assembling all the parts described above is effected in the following manner. 
     In a first step  1 ), the electronic module or modules are mounted on the dissipator bearing  60 . 
     The positioning of each module on the dissipator bearing  60  is facilitated by the two positioning pins  109   a ,  109   b , which will be situated opposite each orifice  609   a ,  609   b  of the corresponding dissipator bearing  60 . 
     The modules are fixed to the dissipator bearing  60  on the one hand by means of an adhesive, for example with glass balls, and on the other hand mechanically in two different ways. 
     According to a first non-limitative way, illustrated in  FIG. 18 , each of the modules is fixed by three studs  113 . The three studs are inserted in the corresponding orifices  608  in the bearing.  FIG. 18  shows the assembly of five modules, three power modules  20 , a control module  30  and an excitation module  40 . 
     According to a second non-limitative preferential way, illustrated in  FIG. 24 , the fixing is effected by means of:
         three studs  226   g  that are put in place after the installation of the signal interconnection piece  22  and that are inserted in the corresponding orifices  681 ,  682 ,  683  in the dissipator bearing  60 , and   a screw  226   v  that is inserted in the associated orifice  684  in the bearing  60 .       

       FIG. 23  shows the assembly of four modules, three electronic modules  10 , one control/excitation module. 
     For the two ways, all the modules are preferentially arranged in the same plane perpendicular to the rotation axis of the rotor of the electrical machine, just like the power tracks and the signal connections, in order to facilitate their assembly. 
     However, in a variant of what is presented in the previous figures, the modules can be disposed on different planes. 
     In a second step  2 ), the signal interconnection piece  22  is mounted on the electronic modules. Because of this, the plate is as close as possible to the modules in order to reduce the length of the signal connections as far as possible and to prevent plugging problems. In this way, the signal connection element  106  of the modules are short; thus their deformation is better controlled (they are less deformable), the connections preferably being flexible. 
     The signal interconnection piece  22  is fixed to the module/bearing assembly in two different ways corresponding to the two ways of fixing the modules to the bearing  60  as described previously. 
     According to a first non-limitative way, illustrated in  FIG. 19 , the signal interconnection piece  22  is positioned by means of the positioning studs  224 , which are positioned opposite the positioning orifices  601   a  and  601   b  of the bearing  60 . Thus, by virtue of this positioning:
         the connection recesses  221   a  are placed opposite the signal tongues  106   a  of the modules;   the connection recesses  221   b  are placed opposite the signal tongues  106   b  of the modules; and   the fixing lugs  222  are placed opposite the studs  113  of the electronic module  10 .       

     Next, after pressing, the signal tongues  106   a  are inserted in the interconnection orifices  2210  of the metal signal tracks TS, the signal tongues  106   b  are inserted in the interconnection orifices  2211  of the metal signal tracks TS, and the lugs  222  are fixed to the studs  113 . 
     According to a second non-limitative preferential way, illustrated in  FIG. 24 , the signal interconnection piece  22  is positioned on the modules by means of the positioning pins  224 , which are positioned opposite the positioning orifices  610   a  and  610   b  of the bearing  60 . Thus, by virtue of this positioning:
         the connection recesses  221   a  are placed opposite the signal tongues  106   a  of the modules;   the connection recesses  221   b  are placed opposite the signal tongues  106   b  of the modules;   the stays  225   a  and  225   b  are placed opposite the support zones  114  of the modules; and   the inserts  226  are placed opposite the corresponding orifices  681  to  684  in the bearing  60 .       

     Next, after pressing, the signal connection elements  106  are inserted in the corresponding recesses  221 , the stays  225  bearing on the support zones  114  of the modules. 
     The studs  226   g , which are inserted in the recesses  221  in the signal interconnection piece  22  and orifices  681 ,  682 ,  683  of the dissipator bearing  60 , are then fixed. The studs bear on the plate and consequently on the plate/modules/bearing assembly so as to afford better mechanical strength. In the same way, the screw  226   v  is screwed into the respective corresponding inserts  226  and  684  in the signal interconnection piece  22  and dissipator bearing  60 . 
     Thus the signal interconnection piece  22  is produced so as to exert a pressure on the power module  20  and the other modules  30 ,  40  in order to guarantee their holding throughout the life of the rotary electrical machine. 
     In a non-limitative embodiment, the material of the plate is PPS (phenylene polysulphide) plastic containing glass fibers. 
     Thus, according to these two ways, the signal plate is deformed in order to exert a pressure on the modules, the deformation preferably being approximately 0.3 mm. In this way, the detachment of the modules is prevented and stresses on the welds of the tongues are avoided. 
     In a third step  3 ), the power interconnection piece  21  is mounted on the bearing/modules/signal plate assembly. The power interconnection piece  21  is fixed above the signal interconnection piece  22 . 
     The power interconnection piece  21  is fixed in two different ways. 
     According to a first non-limitative way, illustrated in  FIG. 20 , the power interconnection piece  21  is placed on the signal interconnection piece  22  so that:
         the fixing lugs  215  are placed opposite the studs  113  of the signal interconnection piece  22 , the studs making it possible to position the power interconnection piece  21 ; and   the power terminals  2120 ,  2110  are placed opposite the corresponding tracks of the electrical conductors  103 ,  104 .       

     In the case of a brush holder, it is positioned so that it is inserted in the recess  605  and the brush cage protector in the recess  603  of the bearing. 
     Next, after pressing, the fixing lugs  215  are fixed on the studs  113 , the power terminals  2120 ,  2110  bear respectively on the ends of the electrical conductors  103 ,  104  of the modules. 
     According to a second non-limitative preferential way, illustrated in  FIG. 25 , the power interconnection piece  21  is placed on the signal interconnection piece  22  so that:
         the inserts  219  are placed opposite the studs  226   g , the orifices and studs serving as a positive location device; and   the lug  218  is placed opposite the holding clip  227  of the signal interconnection piece  22 .       

     Next, after pressing, the inserts  219  are inserted on the studs  226   g  and the lug  218  snaps in the holding clip  227 , and
         the orifice  219   c  is placed opposite a third stud  226   g.          

     In a last step, the cover  70  is mounted on the assembly. In this way, the cover  70  forms a shroud for the rear bearing of the machine. 
     The cover  70  is fixed in two different ways. 
     According to a first non-limitative way, illustrated in  FIGS. 21 and 22 , the cover  70  is placed on the power interconnection piece  21  so that the grooves  77  of the cover  70  are situated opposite the guides  107  of the control module  30 . These guides  107  and grooves  77  serve as a positive location device. 
     Next, after pressing, the grooves  77  are inserted in the guides  107  so that:
         contact is established between the signal tracks  75  of the cover  70  and the signal tongues  106   c  of the control module  30 ; and   contact is established between the power tracks  71  (B+),  72  (B−) of the cover  70  and respectively the power interconnection tracks  212 ,  211  of the power interconnection piece  21 .       

     Finally, after installation of the cover  70 , the electrical connection is made between the power tracks  71 ,  72  of the cover  70  and the power interconnection tracks  212 ,  211  by laser welding via the openings  74 . 
     The cover is fixed by three screws or nuts  78 . 
     According to a second non-limitative preferential way, illustrated in  FIG. 26 , the cover  70  is placed on the power interconnection piece  21  in the same way as the first way with a view to establishing the electrical contacts. In addition, the openings  79  are placed above the three studs  226   g  that fix the electronic assembly. 
     Next, after pressing, the cover  70  is fixed by means of the studs to the electronic assembly (bearing/modules/interconnection plates). 
     In this case, the cover  70  bears on all the elements of the arrangement and thus ensures sufficiently strong support in order both to immobilize the power interconnection piece  21  on the dissipator bearing  60  and to provide the necessary electrical contacts. 
     Thus, as can be seen, according to this first assembly mode, the electronic modules  10 , the signal interconnection piece  22 , the power interconnection piece  21  and the dissipator occupy respectively first, second, third and fourth planes all parallel to one another, and the planes are superimposed in the following order starting from the plane closest to the rear bearing of the machine:
         fourth plane;   first plane;   second plane; and   third plane.       

     Thus the power interconnection piece  21  is independent of the electronic modules and is connected to the modules in particular only by its power electrical terminals. 
     The same applies to the signal interconnection piece  22 , which is connected to the modules in particular only by its signal connection element  106 . 
     2) 2 nd  Assembly Mode or Arrangement 
     According to a second module assembly mode, or arrangement, an electronic module interfaces with the following elements:
         a dissipator  80 ;   a signal interconnection piece  22  according to the third embodiment;   a power interconnection piece  21  according to the third embodiment; and   a cover  70 , according to the third embodiment.       

     Thus the second method of assembling all the parts described above is effected as follows. 
     It should be noted that, in the example taken for this assembly method, there exist four modules that are fixed to the dissipator  80 . Three power modules  20  and one control module  30 . 
     In a first step  1 ), illustrated in  FIG. 27A , the modules are positioned on the top face of the dissipator  80  so as to fix them. 
     The positioning takes place by means of the positioning pins  109   a  and  109   b , which are placed opposite the orifices  810  of the dissipator  80 , and during the positioning the insert  120  of each module comes to be positioned opposite each associated orifice  804  in the dissipator  80 . 
     Subsequently the fixing is carried out by means of:
         fixing screws  1150  that are inserted in the fixing orifices  115  of the modules and the corresponding orifices  804  of the dissipator  80 . These fixing screws  1150  also make it possible to connect the modules to earth via the insert  120 ; and   the signal connector  116  of the control module  30 , which is screwed into the associated orifice  807  of the dissipator  80 , by means of a via screw.       

     During assembly,
         the electrical protection means  126  of the modules are inserted in the recesses  109  of the dissipator provided for this purpose.       

     In addition, the modules are also bonded to the dissipator  80  by means of an adhesive, such as a glass ball adhesive. 
     It should be noted that, prior to the fixing of the control module  30  to the dissipator  80 , the brush holder  50  was fixed to the module by means of the screw  117   a  provided for this purpose. In another variant, it is possible to fix it after the installation of the control module  30  on the dissipator  80 . 
     In a second step  2 ), illustrated in  FIG. 28 , the power interconnection piece  21  is positioned on the bottom face of the dissipator  80  so as to fix the power interconnection piece  21  to the dissipator  80 . 
     The positioning is effected by means of:
         means  214   d  of positioning the power interconnection piece  21  that are opposite the associated positioning orifices  808  in the dissipator; and   the fixing terminal  215   d , which comes opposite the electrical connection orifice  805 .       

     The fixing of the plate  21  on the dissipator  80  is effected by means of:
         the two positioning means  214 , which are placed in the corresponding mechanical positioning orifices  808  in the dissipator  80 ;   the fixing terminal  215   d , which is plugged into the electrical connection orifice  805 ; and   the four force stays  213   d , which are placed opposite the corresponding support zones  814  of the dissipator  80 .       

     During assembly,
         phase protection means  211   d  are integrated in the recesses  812  provided for this purpose in the dissipator.       

     Thus, as can be seen in  FIG. 28 :
         the means  221   d  will protect the phase tongues of the stator;   the axial tongues of the fixing terminals  215   d  are then opposite the corresponding positive electrical conductor  103  (B+) of each electronic module  10 , which will make it possible to establish an electrical connection between the electrical conductor  103  and the positive track  221   d  (B+) of the power interconnection piece  21 ; and   the electrical insert  216   d  integrated in the terminal  215   d  makes it possible to earth the dissipator  80 .       

     In a third step  3 ), illustrated in  FIG. 29 , the signal interconnection piece  22  is positioned on the electronic modules  10  so as to fix it. 
     It should be noted that the signal interconnection piece  22  is pre-positioned (pre-guided) by virtue of two protection pins or guides  107  of two electronic modules  10 , the pins  107  being the furthest away from each other in order to pre-guide well. 
     The positioning is effected by means of:
         the two hollowed-out protuberances  230  serving for pre-guidance and which are pre-positioned on two positioning pins or guides  107  belonging to electronic modules.       

     Then, subsequently, it is possible to position the signal interconnection piece  22  by means of the positioning pins  224  in the corresponding orifices  811  of the dissipator  80 . 
     During assembly, there are:
         the connection recesses  221   a  that are placed opposite the signal tongues  106   a  of the modules;   the connection recesses  221   b  that are placed opposite the signal tongues  106   b  of the modules;   the stays  225   a  and  225   b  that are placed opposite the support  119 ,  114  respectively of the modules; and   the inserts  226  that are placed opposite the corresponding orifices  806  of the dissipator  80 .       

     The fixing takes place by means of:
         insulated hollow rivets  2101   d  associated with the inserts  210   d  of the power interconnection piece  21 . These rivets  2101   d  inside the inserts allow on the one hand an assembly of the signal interconnection piece  22  and on the other hand an insulation of the mass of the dissipator  80  with respect to the mass of the bearing  60 , and finally the creation of an electronic sub-assembly (the two plates, the dissipator  80  and the electronic modules) pre-assembled so that, during assembly on the bearing  60 , by means of screws or studs, after welding the signal connection element  106  with the signal interconnection piece  22 , there are no additional forces that would risk mechanically stressing the welds.       

     Next, after pressing, the signal connection element  106  are inserted in the corresponding interconnection orifices  2210 ,  2211 , the stays  225  bearing on the support  119 ,  114  of the modules. 
     It should also be noted that the housings  231  of the signal interconnection piece  22  comprise in the example illustrated in  FIG. 29  a capacitor associated with each of the power modules  20 , which is connected firstly to the positive electrical conductor  103  (B+) of the associated module and secondly to the negative electrical conductor  104  (B−) of the associated module. 
     In addition, preferentially, it is possible to effect a tin or laser welding, or to deposit a resin plus polymerization in the connection recesses  221   a  and  221   b  of the signal connection element  106  in order in particular to protect them from salt spray. 
     In a fourth step  4 ), illustrated in  FIG. 30A , the whole of the electronics thus obtained are positioned on the rear bearing  90  of the machine. 
     Fixing takes place by means of:
         four studs  226   g  or screws in the rear bearing  90  by means of the inserts  226  of the signal interconnection piece  22 ,  210   d  of the power interconnection piece  21  and fixing orifice  806  of the corresponding dissipator  80 . The studs bear on the same plate and consequently on the plate/dissipator/bearing assembly so as to create an electronic assembly on the bearing. In the same way, the screw  226   v  is screwed in the respective corresponding inserts  226  and  807  of the signal interconnection piece  22  and dissipator  80 .       

       FIG. 30B  is a view in section along the plane X-Y shown in  FIG. 30A , showing an entire assembly of the main parts cited above. It shows in particular:
         the rear bearing  90 ;   the power interconnection piece  21 ;   the dissipator  80 ;   the signal interconnection piece  22 ;   a rivet  2101   d ; and   a fixing stud  226   g.          

     It should be noted that, prior to the electronic assembly, the rear bearing  90  of the machine is fixed to the front bearing (not shown) of the machine by means of four tie rods in orifices  903 , the orifices being illustrated in  FIG. 30C  of the rear bearing  90 . The tie rods are thus screwed before the electronic assembly, which makes it possible to position the phases of the stator in advance and therefore to facilitate the assembly of the electronic sub-assembly with the phases. 
     The rear bearing comprises in particular:
         a positioning orifice  901  configured so as to receive the positioning pin  1151  of the control module  30 , which allows precise positioning of the position sensors with respect to the bearing; and   a referencing orifice  902  in which the pin  212   d  of the power interconnection piece  21  is inserted.       

     The phase hooks  105   cr  are also welded to the phases of the stator (standard wires or using a thimble). 
     Finally, in a fifth step  5 ), the plastic cover  70  is put in place by means of fixing clips that are snapped onto the studs. 
     It should be noted that the steps specified above can be performed in a different order. For example, the second step can of course be performed before the first step ( FIG. 27B  illustrates this case) or after the third step. 
     Thus the second assembly method has the following advantages:
         firstly, the assembly of the entire electronic part (modules, power and signal plates) takes place outside the rear bearing so that it is possible to test the electronics before assembly on the machine; in this way only the electronics that function in the machine are integrated, which saves time in terms of process, and makes it possible to have two independent processes and therefore not to modify the “process” method of standard machine assembly that already exists;   secondly, the assembly of the electronic part can take place after the assembly of the rear bearing of the machine on the front bearing, or more particularly after the fitting of the tie rods fixing the bearings, which will then be covered by the electronics;   thirdly, the performance with regard to thermal cooling is improved because of the axial air flow added to the radial air flow. There is a reduction in pressure drops with an axial air inlet;   fourthly, the cover is now no more than a simple plastic cover. There are no molded-on tracks in the cover, the power tracks and the signal tracks being integrated respectively in the power plate and in the control/excitation module, which makes it possible to limit the number of interconnection welds to be carried out;   fifthly, the earth plane is implemented by the dissipator. There is therefore a reduction in the resistance and inductance of the internal power circuit between the client two-phase power connector and the power module because of the proximity of the positive-polarity track (B+) of the power interconnection piece  21  to the dissipator mass; and   sixthly, the earth plane is implemented by the dissipator, so that there is a saving in axial space. In this way an existing part is used for conveying current.       

     Thus, according to this second assembly method, the electronic modules  10 , the signal interconnection piece  22 , the power interconnection piece  21  and the dissipator occupy respectively first, second, third and fourth planes all parallel to one another, and the planes are superimposed in the following order, starting from the plane closest to the rear bearing:
         third plane;   fourth plane;   first plane; and   second plane.       

     Thus, the power interconnection piece  21  is independent of the electronic modules and is connected to the modules in particular only by its electrical power terminals. 
     The same applies to the signal interconnection piece  22 , which is connected to the modules in particular only by its signal connection element  106 . 
     Thus, all the four parts form an independent electronic sub-assembly of a bearing of the machine. 
     It should be noted that the two assembly methods have the advantage of using the maximum surface available on the rear of the machine for the modules by virtue of the stacking of the various elements for the power and signal interconnections, unlike a solution in which the power and signal interconnection tracks occupy surface on the rear of the machine to the detriment of the modules. 
     It should be noted that the signal interconnection piece  22  according to the various embodiments described above can be used when there is no power interconnection piece  21 . For example with modules themselves effecting their power interconnection. 
     As for the power interconnection piece  21  according to the various embodiments described previously, it can also be used without the signal interconnection piece  22 . For example, with an electronic card PCB effecting the signal interconnection. 
     The assembly according to all the embodiments presented above has the following additional advantages:
         it avoids stacking all the tracks on one another, a stack not being propitious to good holding in position of the tracks;   it comprises means of fixing to the dissipator or to the dissipator bearing that are not concentrated on the periphery of the dissipator or bearing, so that there exists a distribution of forces so as to withstand the mechanical vibrations well;   it enables the various components (interconnection plates and modules) to be in different planes and perpendicular to the rotation axis of the machine, so that it creates more space for the power tracks, which gives rise to a reduction in the resistivity of the tracks. Thus, this assembly makes it possible to convey higher power; and   it makes it possible to use in an optimum fashion the space available for the electronic modules on the rear bearing of the machine, the various components (interconnection plates and modules) being on different planes and perpendicular to the rotation axis of the machine.       

     Naturally, the invention concerns an electronic module that can take different forms and fulfill various functions. 
     In a particular embodiment adapted to a hexaphase rotary electrical machine, the electronic module according to the invention comprises two arms of a bridge rectifier/inverter with MOS transistors to which respectively two phases correspond. In such a case, a complete hexaphase transistor bridge is obtained by means of three electronic modules. FIGS.  4 B′ and  4 E′ show a module of this type comprising two phase tracks and corresponding hooks  105 CR and  105 CR′. The electrical connections to the polarities B+ and B−of the battery are provided through electrical conductors  103  (B+) and  104  (B−) of the module. As shown in FIGS.  4 B′ and  4 E′, the electrical conductor  103  (B+) is in the form of a tongue and the electrical conductor  104  (B−) is produced by means of a metal insert  120  in the form of a ring in which a fixing screw is housed. The insert  120  is in contact with an earth track  104  (B−)′ of the module (shown in FIG.  4 B′) so as to provide electrical continuity. In a variant, the electrical conductor  104  (B−) can be provided directly by an electrical contact between the earth track  104  (B−)′ and a corresponding conductive portion, external to the module, when the electronic module is assembled on the rotary electrical machine. 
     While the form of apparatus herein described constitutes a preferred embodiment of this invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.