Axial magnetic flux electric machine with a wound rotor and three-phase electrical power supply.

Abstract

An axial magnetic flux electric machine 200 comprising: a central discoidal rotor 100 with a structure composed mainly of two flanges 110a, 110b of composite material which support rotor cores 130 of magnetic field, in multiples of three, each surrounded by a coil 140; Two lateral stators 220, 230 built on the basis of a frame 221, 231 of composite material, comprising a radial face 221r, 231r with openings which accommodate the stator pads 222, 232, separated from the rotor 100 by air gaps 241, in multiples of two, each carrying a coil 223, 233, and connected to each other, at the rear end, by a yoke 227, 237; A device 300 for supplying electric current to the rotor comprising the rotating elements 320, 330, 340, 350 in insulating material carrying the crown-shaped plates 331, 341, 342, 351 in conductive material and each having a connection tab 331u, 341v, 342w, 351n to the rotor commutators 141, 142, 143,144 by the supply wires 151, 152, 153, 154, fixed elements 360, 370 made of insulating material carrying crown-shaped plates 361, 362, 371, 372 made of conductive material and each having a tab 361u, 362v, 371w, 372n for connection to the external power supply, current-transmitting discs 380 interposed between the rotating movable crown-shaped plates and the fixed crown-shaped plates, characterized in that: The rotor coils 100 are supplied with three-phase alternating current via the variable-frequency power supply device 300, which allows the rotational speed of the electric machine to be controlled. The stator is supplied with direct current, which allows the torque and power of the electric machine to be controlled. Figure for the abstract: Fig. 9,

Description

Title of the invention: Axial magnetic flux electric machine with a wound rotor and three-phase electrical supply. TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates generally to the field of axial magnetic flux electrical machines.

[0002] It relates firstly to a discoid rotor with wound magnetic poles, supplied with three-phase electric current, and its cooling method.

[0003] It relates to a stator associated with wound magnetic poles, supplied with direct electric current, and its cooling method. STATE OF THE ART

[0004] Axial magnetic flux electric machines are still not widespread in the field of automotive electric traction.

[0005] These machines exist according to two architectures.

[0006] In the first type, the rotor is single, central, and flanked by two stators. The rotor carries permanent magnet pads, more or less segmented to reduce heat generation, and the stators carry coils supplied with alternating current of variable frequency, intensity, and voltage. All speed and power control is achieved via the stator. Stator cooling is generally provided by a network through which a liquid circulates. Cooling the rotor, confined between the stators, is difficult to implement and is often nonexistent. FR2999359 provides an example.

[0007] In the second type, the stator is single, central, and flanked by two rotors. The rotors also carry permanent magnet pads, more or less segmented, and the stators also carry coils supplied with three-phase alternating current of variable frequency, intensity, and voltage. All speed and power control is also achieved via the stator. Stator cooling is generally achieved more efficiently by the circulation of a liquid in direct contact with the coils. Since the two rotors are arranged laterally to the stator, their cooling is facilitated by forced circulation of air from outside the machine. US publication 10630157B2 is an example.

[0008] There do not appear to be any publications relating to an axial magnetic flux machine with a central wound rotor supplied with three-phase alternating current. PRESENTATION OF THE INVENTION

[0009] The advantage of designing a wound-rotor electric machine is that it does not require permanent magnets and is independent of so-called earths rare.

[0010] The advantage of designing a wound-rotor machine supplied with three-phase alternating current and of separating the control of the power and the rotational speed.

[0011] The rotor's rotational speed is determined by the identical sinusoidal frequency of the three phases of the electric current, shifted by 120°, which creates a rotating magnetic field. The maximum intensity of the magnetic field in each coil will be a function of the maximum current intensity.

[0012] To power the rotor, it is sufficient to have an inverter capable of delivering a three-phase alternating current of variable frequency and fixed and low intensity, which makes it less expensive than those powering the stators with variable and high intensity.

[0013] Indeed, for a conventional machine with a magnet rotor or wound rotor supplied with direct current, the inverter controls the speed and power. It must be capable of supplying a three-phase alternating current of variable frequency and variable and high intensity.

[0014] To operate this machine with a wound rotor supplied by three-phase current, the stator will be supplied with variable-intensity direct current. It controls the machine's power. Its power supply is simple since the energy source (the battery) delivers direct current.

[0015] The invention therefore relates to an axial magnetic flux electrical machine comprising: • A central discoidal rotor with a structure composed mainly of two composite material flanges which support magnetic field conducting cores, in a number that is a multiple of three, each surrounded by a coil powered by one of the three phases of an alternating current, and an arrangement of the cores allowing air circulation to cool the coils. • Two lateral stators constructed on a composite frame, comprising an outer ring, an inner ring, and a radial face with openings for stator contacts (a multiple of two), facing each other a short distance from the rotor. Each contact carries a coil and is connected to each other at the rear end by a magnetic flux loop. The frame, closed on the opposite side of its radial face by a cover, forms a sealed chamber through which a cooling fluid circulates. The coils are supplied with variable-intensity direct current, such that two consecutive coils generate a magnetic field in opposite directions, and two opposing stator contacts, one belonging to the left stator and the other to the right stator, create fields in the same direction. DETAILED DESCRIPTION OF THE INVENTION

[0016] These features, objectives and advantages of the present invention will become apparent from the detailed description that follows and from the accompanying drawings given by way of non-limiting examples and on which:

[0017] [Fig. 1] is a front view of the assembled rotor disk.

[0018] [Fig.2] is a front view of the incomplete disc, without the peripheral reinforcing band and without the front flange.

[0019] [Fig.3] is a first section AA of the assembled disk.

[0020] [Fig.4] is a second BB section of the assembled disk.

[0021] [Fig.5] is a third CC section of the assembled disk.

[0022] [Fig.6] is a fourth DD section of the assembled disk.

[0023] [Fig.7] is the description of the left stator.

[0024] [Fig.8] is the description of the right stator.

[0025] [Fig.9] is a cross-section of the electrical machine.

[0026] [Fig. 10] is a partial cross-section of the electric machine, with focus on the rotor power supply device.

[0027] [Fig. 1 l]is a UU section of the rotor power supply device corresponding to phase 1.

[0028] [Fig. 12] is a VV section of the rotor power supply device corresponding to phase 2.

[0029] [Fig. 13] is a WW section of the rotor power supply device corresponding to phase 3.

[0030] [Fig. 14] is a section NN of the rotor power supply device corresponding to the neutral phase.

[0031] [Fig.15] is a view of the transmitter disk and its section MM.

[0032] [Fig. 16] is a view of the cooling airflow in the rotor disc.

[0033] [Fig. 17] is a cross-sectional view of the electrical machine describing the re device liquid cooling of the stators.

[0034] [Fig. 18] is a view of the rotor cooling air circulation in the closed space of the electric machine.

[0035] [Fig. 1] is a front view of the discoid rotor 100 for an axial magnetic flux electric machine. This rotor comprises 2 flanges, flange 110a is shown from the front in this view.

[0036] This flange has substantially trapezoidal openings 11 la, the number of which is always a multiple of three but varies according to the performance required for the electric machine. Each of these openings receives one end of the magnetically conducting rotor cores 130, the other end being supported by the second rear flange.

[0037] We have a circular centering opening 112a which serves to position the rotor discoid 100 on its guide bearing.

[0038] On a first diameter, we have a series of holes. These are the holes 113a for the passage of screws for fixing the discoid rotor 100 and the holes 114a for the passage of the pin contributing to the transmission of torque.

[0039] On a second diameter we have circular zones 115a set back from the surface, of the same number as the rotor cores 130, occupied by the heads of the rivets 160 for joining the two flanges.

[0040] On a slightly larger diameter, we have a series of inclined air inlet ducts 117a, from the air inlet 117al on the outer surface of the flange 110a to the air outlet 117a2 on the inner surface (specified later). According to the inclination shown in this figure, the air inlet ducts will only be effective for the direction of rotation 101. For an electric motor equipping a vehicle, this direction of rotation must correspond to forward motion.

[0041] Finally, on a peripheral diameter, we have semi-circular zones 116a set back from the surface, of the same number as the rotor cores 130, occupied by the heads of the rivets 161.

[0042] These rivets 161 locally secure the two flanges with the peripheral band 120 on its inner protrusions 120a, which are narrower than the band itself and on which the two flanges are pressed (see [Fig.3]).

[0043] The role of this band 120, on which the flanges can be centered with radial clamping, is to substantially increase the resistance of the flanges to the centrifugal forces generated by the rotor cores 130, each of which carries a coil, and thus allow a higher limiting rotational speed.

[0044] The mention of air inlet ducts 117a means internal air circulation in the discoid rotor 100. This circulation will be natural thanks to centrifugation during rotation and because the air outlet openings 121 are on the periphery in the ring 120 and facing each rotor core 130.

[0045] [Fig.2] is a front view of the discoidal rotor 100 without the rim 120 and the flange 110a is shown in [Fig. 1]. This figure shows a view of the inside of the discoid rotor 100.

[0046] We see the inner face of the flange 110b, and find the same orifices, namely, a centering opening 112b which serves to position the discoid rotor 100 on its guide bearing, the screw passage holes 113b for fixing the discoid rotor and the pin passage holes 114b for contributing to the transmission of torque.

[0047] On a second diameter we have the holes 115b for the passage of the internal rivets 160 for joining the two flanges.

[0048] On a slightly larger diameter, we have a series of air ducts 117b inclined from the external air inlet 117b 1 to the internal air outlet 117b2 in accordance with the direction of rotation 101 (117b 1 ahead of 117b2).

[0049] The rotor cores 130 each carry a coil 140, each connected to two commutators: • to the collector 141 for the U phase (1) by the end of the wire 140a of the winding and to the collector 144 for the neutral phase by the other end of the wire 140d; • to the collector 142 for phase V (2) by the end of wire 140b of the winding and to the collector 144 for the neutral phase by the other end of wire 140d; • to the collector 143 for the W phase (3) by the end of the wire 140c of the winding and to the collector 144 for the neutral phase by the other end of the wire 140d.

[0050] Each coil produces an alternating magnetic field and the superposition of these fields gives a rotating resultant field which drives the rotor at the same speed, i.e. synchronous with that of the resultant field created by the coils of the rotor, because circulating in the axial magnetic fluxes, of constant orientations, generated by the stator pads.

[0051] These four collectors are connected to an external power supply by four wires: • the collector 141 for phase U (1) to the supply wire 151; • the collector 142 for phase V (2) to the supply wire 152; • the collector 143 for phase W (3) to the supply wire 153; • the collector 144 for the neutral phase to the supply wire 154; These power supply wires 151, 152, 153, 154 pass through the wall of the flange 110b.

[0052] Finally, on a peripheral diameter, we have semi-circular recessed areas 116b relative to the external surface of the flange 110b, of the same number as the rotor cores 130, occupied by the heads of the rivets 161 (not shown).

[0053] [Fig. 3] is section AA of the discoidal rotor 100. The two flanges 110a, 110b are joined and internally secured by rivets 160. Externally the rivets 161 secure the two flanges 110a, 110b with the band 120 at the level of each internal protrusion 120a.

[0054] The rotor core 130 passes through the two flanges and is externally flush. The coil 140 occupies the entire axial space of the annular chamber 110c formed by the flanges 110a, 110b.

[0055] the annular chamber 110c of the flanges extends towards the axis of rotation under the coils for the passage of the collectors 141,142,143 and 144.

[0056] Close to the inner diameter 1 lOd of the annular chamber 110c, and facing the collectors, are the inclined air inlet ducts 117a and 117b, and in the ring 120 the air outlet opening 121 of width slightly less than that of the annular chamber 110c.

[0057] The rotor cores 130 are made of material with the lowest possible reluctance, which should generate the least possible loss due to eddy currents. They can be of different compositions: SMC, a stack of thin sheets electrically insulated from each other and of several widths to form a figure close to a trapezoid, or a bundle of wires electrically insulated from each other and tangent to each other.

[0058] The rotor cores 130 have an overmolding 131 made of insulating material in two different thicknesses. In the central zone, the overmolding 131b is thicker and serves two purposes. The first is to axially secure the core. Indeed, having a perimeter larger than that of the substantially trapezoidal openings 11a, 11b and having a length equal to the width of the annular chamber 110c, the overmolding 131b is laterally secured to the flanges 110a and 110b and also secures the core. The second purpose of this overmolding 131b is to serve as a cradle for the coil 140, this cradle being completed laterally by the flanges. At the ends 131a, the thickness of the overmolding gives the core its final dimensions, conforming to the trapezoidal openings 11a and 111b.

[0059] [Fig.4] is the BB section of the discoid rotor 100. In the annular chamber 110c formed by the two flanges 110a, 110b and the ring 120 are installed, in the free area under the coils, the circular collectors 141, 142, 143 and 144.

[0060] At the collector 144, the one with the smallest diameter, corresponding to the neutral phase, is soldered the power supply wire 154 for connection to the external alternating current supply. This power supply wire 154 passes through the flange 110b via the opening 110b4 in the immediate vicinity of the inner diameter 110d of the annular chamber 110c.

[0061] The power supply wire 151 for connection to the external AC power supply is soldered to the collector 141, the one with the largest diameter, corresponding to phase 1 (U). This power supply wire 151 passes through the flange 110b via the opening 11 Obi in the immediate vicinity of the inner diameter 1 lOd of the annular chamber 110c.

[0062] [Fig. 5] is section CC of the discoid rotor 100. It incorporates many elements of section AA. This section shows the connection of a coil 140 to the neutral collector 144 by welding the end of the wire 140d. This section also shows the connection of the collector 142, corresponding to phase 2 (V), to the external power supply via the power supply wire 152. It passes through the flange 110b via the opening 110b2.

[0063] [Fig. 6] is section DD of the discoid rotor 100. This section shows the connection of one coil to the commutator 141, corresponding to phase 1 (U) by the soldering of the end of wire 140a. This section also shows the connection of another coil to the commutator 143, corresponding to phase 3 (W) by the soldering of the end of wire 140c.

[0064] The discoidal rotor 100 is part of a magnetic flux electric machine 200 axial comprising two stators 220 called left and 230 called right.

[0065] In [Fig. 7], the stator 220 is constructed on the basis of a frame 221 made of material composite. It can be divided into three main parts: • an outer ring 221e extending axially towards the rear; • an inner ring 221i also extending axially towards the rear; • a radial flat face 221r ​​for connecting the two rings.

[0066] On the outer ring 221e we have various outgrowths: • 221el corresponds to the fixing points on the central spacer 240 of the machine (see machine cross-section [Fig.9]); • 221e2 corresponds to the positioning bushings relative to the spacer 240 and the opposite carcass; • 221e3 and 221e4 correspond to the supply and drainage of the fluid cooling (see [Fig. 17]); • 221e5 corresponds to a trench, in the rear area of ​​the outer ring 221e allowing a watertight passage of the electrical conductors supplying the coils with direct current; • 221e6 corresponds to material removals relative to the front face, allowing the passage of cooling air from the rotor disc to the internal space of the electric machine 200 (see [Fig. 18]).

[0067] On the inner ring 221i we have different arrangements: • 221 it corresponds to the fixing points of the cover 228 (see [Fig.9] )closing the coolant circulation chamber; • 221i2 corresponds to notches facilitating looped air circulation in the internal space of the electrical machine (see [Fig. 18]); • 221i3 corresponds to carcass lightening zones.

[0068] The radial face 221r ​​for connecting the outer and inner rings 221e 221i appears in the form of rods because this radial face has trapezoidal openings 221pl for receiving the stator pads 222. Around the perimeter of each trapezoidal opening 221pl, there is a rearward extension 221p2 that surrounds the stator pad 222 (a stack of laminations 222f forming a trapezoid). On the bases of the trapezoid, longitudinal channels 221p3, which will be filled with adhesive 222a during the assembly process (see [Fig. 9]), reinforce the connection of the stator pads 222 with the frame 221, in addition to the bead of adhesive 222b around the pad head.

[0069] Around each stator contact 222, and carried rearward by the extensions 221p2, there is a coil 223 which, when supplied with direct current, creates a magnetic field whose intensity is proportional to the intensity of the electric current. The extensions 221p2 are externally the insulating supports for the coils 223.

[0070] Near the inner perimeter of the outer ring 221e of the frame, two closed and circular electric current collectors 224a,224b (one masking the other in this view) are connected to the coils 223.

[0071] The coils 223 are of an even number and are supplied in parallel by each being connected to the collectors 224a,224b by the two ends 223a and 223b of the wire of each coil.

[0072] For obtaining magnetic fluxes of opposite direction between two adjacent coils, knowing that for all coils the wire has the same winding direction, the connections of the ends 223a and 223b of the wires of coils 223, with the collectors 224a and 224b must be such that two connections of the ends 223a are adjacent alternating with two connections of the ends 223b adjacent.

[0073] An external power supply (not shown) is connected to the collectors 224a,224b by wires 225a and 225b.

[0074] In [Fig. 8], the stator 230, referred to as the right-hand stator, is shown in front view. Its frame 231 is the mirror image of that of the left-hand stator 220, with one difference: there is an angular offset of a few degrees between the mounting points 231el on the spacer, so that the screw threads are not directly opposite each other, and their engagement length is sufficient without affecting the thickness of the spacer. Indeed, we will see in the description of the electrical machine (see [Fig. 9]) that the thickness of the spacer 240 is precisely equal to the sum of the thicknesses of the two air gaps 241 and the discoidal rotor 100.

[0075] For the rest, the description of the right stator 230 is similar to that of the left stator 220.

[0076] Thus, the stator 230 is constructed on the basis of a frame 231 made of composite material. Three main parts are distinguished: • an outer ring 231e extending axially towards the rear; • an inner ring 231i also extending axially towards the rear; • a radial face 23 Ir flat for connecting the two crowns.

[0077] On the outer ring 231e we have various outgrowths: • 231el corresponds to the fixing points on the central spacer 240 of the machine and which are subject to an angular offset with the 221el fixings; • 23le2 corresponds to the positioning bushings relative to the spacer 240 and the opposite carcass 221; • 231e3 and 231e4 correspond to the supply and drainage of the refrigerant cooling (see [Fig. 17]); • 231e5 corresponds to a trench, in the rear area of ​​the ex crown external 231e allowing a watertight passage of the electrical conductors 235a,235b supplying the coils with direct current (see [Fig.9]); • 231e6 corresponds to material removals relative to the front face, allowing the passage of cooling air from the rotor disc to the internal space of the electric machine 200 (see [Fig. 18]).

[0078] On the inner ring 23 li we have different arrangements: • 231 it corresponds to the fixing points of the cover 239 (see [Fig.9] )closing the coolant circulation chamber; • 231i2 corresponds to notches facilitating looped air circulation in the internal space of the electrical machine (see [Fig. 18]); • 231i3 corresponds to carcass lightening zones.

[0079] The radial face 23 Ir of connection of the outer 231e and inner rings 23 li appears in the form of rods because this radial zone has trapezoidal openings 231pl for receiving the stator pads 232. Around the perimeter of each trapezoidal opening 231pl, there is a rearward extension 231p2 that surrounds the stator pad 232 (a stack of laminations 232f forming a trapezoid). On the bases of the trapezoid, longitudinal channels 231p3, which will be filled with adhesive 232a during the assembly process (see [Fig. 9]), reinforce the connection of the stator pads 232 with the frame 231, in addition to the bead of adhesive 232b around the pad head.

[0080] Around each stator pad 232, and carried by the extensions towards the rear 231p2, is a coil 233 which, when supplied with direct current, creates a magnetic field of intensity proportional to the intensity of the electric current.

[0081] Near the inner perimeter of the outer ring 231e of the frame, two closed and circular electric current collectors 234a,234b, one masking the other in this view, are connected to the coils 233.

[0082] The coils 233 are of an even number and are supplied in parallel by each being connected to the collectors 234a,234b by the ends 233a and 233b of the wire each coil.

[0083] For obtaining magnetic fluxes of opposite direction between two adjacent coils, knowing that for all coils, the wire has the same winding direction, the connections of the ends 233a and 233b of the wires of coils 233, with the collectors 234a and 234b must be such that two connections of the ends 223a are adjacent alternating with two connections of the ends 223b adjacent.

[0084] An external power supply (not shown) is connected to the collectors 234a,234b by the conductor wires 235a and 235b.

[0085] [Fig.9] is a cross-sectional view of the axial magnetic flux electric machine 200, equipped with the wound discoid rotor 100. It is contained in the housing 210 closed by the closing flange 211 fixed to the housing by means of the screws 212.

[0086] The discoidal rotor 100 is framed by the stators 220, 230. Section of the left stator 220 is along the AA line of [Fig.7]. The section of the right stator 230 is along the BB line of [Fig.8].

[0087] The stators 220,230 are constructed on the basis of a frame 221,231 provided with a series of openings bordered by an axial extension 221p2,231p2, towards the rear, for receiving the stator pads 222,232.

[0088] The stator pads are glued along their entire length in the channels 221p3 and 231p3 and on the front periphery by the cords 222b,232b.

[0089] Externally, these axial extensions 221p2,231p2 carry the coils 223,233.

[0090] The magnetic circuit is closed at the rear of the stator pads 222,232 by the annular yokes 227,237 made of rolled sheet metal and glued to the stator pads 222,232.

[0091] The housings 221, 231 with axial extensions in outer rings 221e, 23e and inner rings 221i, 231i, with an annular radial face 221r, 231r whose openings 221pl, 231pl are obstructed by the stator posts 222, 232, form hollow annular volumes closed by the annular covers 228, 238. These sealed stator chambers 221v, 231v are occupied by the stator posts 222, 232, the coils 223, 233 and the yokes 224, 234, and the remaining free space allows the circulation of a coolant which will be in direct contact with the coils and the yokes.

[0092] The coils 223, 233 are supplied with direct current. The two ends of the wires 223a, 223b and 233a, 233b are in contact (soldered) with the commutators 224a, 224b and 234a, 234b, respectively. On the right-hand stator 230, the conductor wires 235a and 235b, which connect to the external direct current supply, are visible. An elastomer pad 236 allows the two conductor wires 235a and 235b to pass through the outer ring 231e in a watertight manner. The same device is present on the stator 220, but it is not shown.

[0093] The covers 228,238 are fixed on their inner diameter by the screws 229 (not shown),239 and on their outer diameter by the screws 243, a common fixing means with the carcasses 221,231 of the stators on the central spacer 240.

[0094] This central spacer 240, annular, is the intermediate element between the stators 220,230 and the housing 210. On its periphery it has several lugs 240a through which the screws 242 pass on the bearing surfaces 210a.

[0095] In the inner area of ​​this central annular spacer 240, the discoidal rotor 100 is arranged. It carries on either side and at a precise distance the two stators 220,230. The thickness of the spacer 240 is precisely equal to the sum of the thicknesses of the discoidal rotor 100 and the two air gaps 241.

[0096] Between two consecutive ears 240a, the spacer 240 is set back from the fabric of the housing 210 and provides a passage for air circulation in the unoccupied internal spaces 214, formed by the housing 210 and the closing flange 211.

[0097] The housing 210 has a general shape close to a slightly conical cylinder (foundry draft) closed on one side by a 210b canvas. In the center of this canvas, in the 210c boss, an axle 250 is fitted without play.

[0098] On its free part extending beyond the boss 210c, the shaft 250 carries a double row ball bearing 260 with angular contact.

[0099] This bearing 260 consists of an outer ring 261, two inner rings 262, 263 between which the balls 264 are interposed. The inner rings 262, 263 are pressed together. This bearing 260 is characterized by the absence of internal play and a slight preload. The ring 263 is indirectly axially supported on the boss 210c, because the balancing washer 270 for the air gaps 241 is interposed between the latter and the ring 263. The entire assembly is held tightly by the screw 252 and the pressure washer 251.

[0100] The outer ring 261 has an annular radial extension 261a. On one side of this extension rests the discoidal rotor 100, centered on the outer diameter. On the opposite side is arranged the rotor's electrical current supply device 300, secured by screws 301.

[0101] Against the discoid rotor 100 is supported a power transmission hub 280, also centered on the outer diameter of the ring 261 of the bearing 260. The screws 285 pass through the radial extension 261a, the discoid rotor 100 and secure them with the power transmission hub 280.

[0102] The power transmission hub 280 externally carries the rotor 291 of the resolver whose stator 290 is positioned on the closing flange 211. In its hollow part, the power transmission hub 280 accommodates the grounding device 287, protecting the bearing 260 from possible parasitic currents, and a ball slide 282 equipped with a grooved ring 281, protecting the machine from external axial stresses detrimental to the stability of the air gaps 241.

[0103] [Fig. 10] is a cross-sectional view of the electrical power supply device 300.

[0104] This device is composed of several elements, some of which are mobile in rotation and others fixed, because its role is to transmit electric current from an external three-phase supply (not shown) to the electric machine 200 to its discoid rotor 100 which is rotating by definition.

[0105] The entire device is installed on a metallic support 310 centered by its diameter 310a and is supported by its face 310b on the radial extension 261a of the outer ring 261 of the bearing 260.

[0106] The support 310 has a tubular shape 310c. Externally, grooves 310d are cut which drive the rotating elements of this feeding device, and near the end, a groove 310e is cut to receive a retaining ring.

[0107] Carried by the groove, are stacked from right to left: • a first rotating element 320 in the shape of an annular disc, made of insulating, and with a grooved inner diameter; • A second rotating element 330, made of insulating material, with an end in the shape of an annular disc and a tubular part 330a grooved externally. • A third rotating element 340, made of insulating material, carried by the second 330, in the form of an annular disc with a grooved inner diameter and whose cross-section has the shape of a T. • A fourth rotating element 350, made of insulating material, carried by the second 330, in the form of an annular disc with a grooved inner diameter and of any shape.

[0108] In the first element 320, several radial grooves are cut. [Fig. 10] is a cross-section of the phase 2 power supply device. The groove 320v houses the tab 341v attached to the power supply wire 152 connected to the collector 142.

[0109] In the annular part of the second rotating element 330 is fixed a ring-shaped plate 331 made of conductive material, copper or copper alloy, which is fixed in rotation.

[0110] On either side of the third rotating element 340 are fixed two crown-shaped plates 341,342 identical to the crown-shaped plate 331, made of conductive material, copper or copper alloy, and fixed together in rotation.

[0111] Similarly, in the fourth rotating element 350 is fixed a crown-shaped plate 351 identical to the previous ones, made of copper or copper alloy, fixed in rotation.

[0112] Between the second 330 and the third 340 rotating element, a first fixed element 360, made of insulating material, is arranged.

[0113] Between the third 340 and the fourth 350 rotating element a second fixed element 370, made of insulating material, is arranged.

[0114] These two fixed elements 360,370 in the form of an annular disc, made of insulating material, are centered on the tubular part 330a of the second rotating element 330.

[0115] These two fixed elements 360,370 each have an outgrowth 360a,370a, which cooperate with a pin 217, for locking against rotation, screwed into the casing 210 of the electrical machine.

[0116] These two fixed elements 360,370 each carry on either side of the central insulating core a ring-shaped plate made of conductive material identical to those fixed to the rotating disks.

[0117] The central core of the fixed element 360 is framed by the fixed crown-shaped plates 361,362.

[0118] The central core of the second fixed element 370 is framed by the crown-shaped plates 371,372.

[0119] In summary, we are faced with: • of three support elements in insulating material, 330,340,350 movable in rotation carrying four crown-shaped plates, in conductive material 331 for the first, 341 and 342 for the second and 351 for the third, for the three phases and the neutral; • Two fixed support elements made of insulating material, 360,370 blocked in rotation and carrying four crown-shaped plates made of conductive material, 361,362 for the first 360 and 371,372 for the second 370 for the three phases and the neutral.

[0120] Opposite each rotating mobile crown-shaped plate 331,341,342,351 is, respectively, a rotationally blocked crown-shaped plate 361,362,371,372.

[0121] For the transmission of electric current from the external power supply to the rotor, an electrical contact must be established between the pairs of opposite plates.

[0122] Also, between the two crown-shaped plates 331,361 then 362,341 then 342,371 and 372,351 are intercalated four transmitting discs 380 centered on their outer diameter, the first in the second rotating element 330, the second and third in the third rotating element 340 and the fourth in the fourth rotating element 350.

[0123] These four transmitting discs 380, see [Fig. 15], are similar to those of needle bearings, but play a very different role. They consist of an annular disc 381 made of insulating material which has, on two concentric circles, a large number of rectangular openings in which are inserted cylindrical rollers 382, ​​all identical, made of conductive material, copper or copper alloy, with a diameter greater than the thickness of the annular disc 381.

[0124] The choice of a very large number of rollers 382 is the way to split the electric current and limit it, for each contact, to a low intensity level reducing the risks of electric arc and damage.

[0125] These rollers are subjected to a very low axial load which ensures the contact, for the transmission of the electric current, of the greatest possible proportion of rollers 382 with the ring-shaped plates from 361 to 331 then from 362 to 341 then from 371 to 342 and from 372 to 351.

[0126] For this purpose, the rotating elements 350, 340, 330, 320, the fixed elements 360, 370 and the four transmitting discs 380 are pressed against each other and against the support element 310 by a wave washer type spring 390 arranged in a circular groove 350b of the fourth complementary rotating element 350, put under tension by the washer 391 held by the stop ring 392 engaged in the groove 310e of the support 310.

[0127] Each crown-shaped plate has a connection tab either with the rotor coils or with the external power supply.

[0128] In [Fig. 10] the connections correspond to phase 2. The rotating ring-shaped plate 341 has a tab 341v. It passes under the first fixed element 360 in an axial groove 330v of the element 330, crosses the radial area of ​​the second element 330 in an opening 330vl, then is bent and takes a radial direction in the groove 320v and connects to the supply wire 152 connected to the commutator 142. The ring-shaped plate 362 carried by the first fixed element 360, separated from the ring-shaped plate 341 by a transmitter disc 380, has a tab 362v which exits the electric machine through the tab guide 395 made of insulating material engaged in the opening 215 of the housing 210 and retained by the retaining ring 216.

[0129] To ensure the longevity of the electrical power supply device 300, the rollers 382 will be coated with conductive bearing grease. This grease will be retained and confined by the felt seals 396 closing the gaps between the fixed and rotating elements.

[0130] [Fig. 11] is a cross-sectional view UU of the electrical power supply device 300 according to phase 1. The fixed ring-shaped plate 361 is powered by the tab 36lu connected to the external power supply. Between the fixed ring-shaped plate 361 and the rotating ring-shaped plate 331, a transmitter disc 380 is interposed. The rotating ring-shaped plate 331 powers the disc-shaped rotor wound by the tab 33lu.

[0131] [Fig. 12] is a cross-sectional view VV of the electrical power supply device 300 according to phase 2 (see also paragraph

[0129] ). The fixed ring-shaped plate 362 is supplied by the tab 362v connected to the external power supply. Between the fixed ring-shaped plate 362 and the rotating ring-shaped plate 341, a transmitting disc 380 is interposed. The rotating ring-shaped plate 341 supplies the disc-shaped rotor wound by the tab 34Iv which passes under the first fixed element 360 in an axial groove 330v of the tubular element 330a, then is bent and takes a radial direction in the groove 320v.

[0132] [Fig. 13] is a cross-sectional view WW of the electrical power supply device 300 according to phase 3. The fixed ring-shaped plate 371 is supplied by the tab 37Iw connected to the external power supply. Between the fixed ring-shaped plate 371 and the rotating ring-shaped plate 342, a transmitting disc 380 is interposed. The rotating ring-shaped plate 342 supplies the wound discoid rotor via the connecting tab 342w which passes under the first fixed element 360 in an axial groove 330w of the tubular element 330a, then is bent and takes a radial direction in the groove 320w.

[0133] [Fig. 14] is a cross-sectional view NN of the electrical power supply device 300 along the neutral phase. The fixed ring-shaped plate 372 is supplied by the tab 372n connected to the external power supply. Between the fixed ring-shaped plate 372 and the rotating ring-shaped plate 351, a transmitting disc 380 is interposed. The rotating ring-shaped plate 351 supplies the wound discoid rotor via the connecting tab 35 In which passes under the fixed elements 370, 360 in an axial groove 330nd of the tubular element 330a, then is bent and takes a radial direction in the groove 320n.

[0134] [Fig. 15] is the presentation of the 380 transmitter disk. See the description in paragraph

[0123] .

[0135] [Fig. 16] is a partial front view of the discoid rotor 100. On the flange 110a, below each coil 140, i.e., the part closest to the axis of rotation, there is an air inlet 117a inclined with respect to the axis of rotation of the discoid rotor 100. This opening is an air circulation duct between the unoccupied volume inside the housing and the unoccupied volume inside the annular chamber 110c. For the direction of rotation 101 indicated, the introduction of air into the annular chamber 110c is facilitated by an air inlet 117a1, related to the internal volume of the housing, which is angularly advanced over the air outlet 117a2, related to the internal volume of the annular chamber 110c. The air outlet 117a2 is centered relative to the coil 140.

[0136] In the ring 120, the air outlet openings 121 are, conversely, an air circulation duct from the annular chamber 110c to the internal volume of the housing, the openings are centered with respect to the coils 140.

[0137] Arranged in this way, the air circulation between the air inlets 117a,117b and the air outlet 121 of the annular chamber 110c is as follows: • aspiration through air inlets 117a 1,117b 1 and expulsion through air outlets 117a2,l 17b2 of air inlet ducts 117a, 117b inclined along the path 118a; • the incoming flows are shared at the bottom of the coils 140, equally or not, and bypass them according to the paths 118b 1,118b2; • the two flows come together at the top of each coil and exit the annular chamber 110c through the air outlet opening 121 along the path 118c.

[0138] [Fig. 17] shows in cross-section the electric machine 200 according to the defined CC sections on [Fig.7] and [Fig.8].

[0139] The stator cooling device 220,230 by circulation of a liquid fluid, in the stator chambers 22 Iv and 23 Iv is presented because it also participates in the cooling of the ambient air in the internal spaces 214 in communication between them, of the casing 210 and of the closing flange 211 of the machine 200, and not occupied.

[0140] The cooling fluid supply and discharge conduits 244a and 244e are attached to the central spacer 240. As shown in sections CC of [Fig.7] and [Fig.8], these conduits are arranged as follows: the supply conduit 244a is near the highest area of ​​the electrical machine 200 and the discharge conduit 244e is near the lowest area, and they are diametrically opposed.

[0141] These angled conduits enter the machine by passing through an elastomer block 213 housed in a suitable opening 210d of the housing, blocked by the closing flange 211.

[0142] The supply conduit 244a communicates with the radial conduit 245a, sealed by the operculum 246. The seal between the spacer plate 240 with the left 221 and right 231 frames is ensured by the O-rings 247.

[0143] The radial conduit 245a opens into two axial conduits 221e7 and 231e7 which supply the stator chambers 221v and 231v of the stators through the openings 221e8 and 231e8 ​​at the ends of the axial outer rings 221e and 231e of the frames.

[0144] The coolant circulates in the stator chambers 221v and 23Iv and absorbs the heat released by the Joule effect in the coils and the eddy currents in the stator cores and the yokes.

[0145] The coolant is also in contact with the covers 228, 238, which externally carry radial fins 228a, 238a in contact with the ambient air of the unoccupied internal spaces 214 of the machine 200, and is thus able to absorb heat from this ambient air. This is the reason for the presentation of the stator cooling device, which indirectly contributes to the cooling of the discoidal rotor 100.

[0146] Draining the stator chambers 221v and right 23Iv is carried out in a similar manner to the supply through the communication openings 221e9,231e9, then through the axial conduits 221el0,231el0, which join in the single radial conduit 245e, obstructed by the operculum 246 and finally by the bent conduit 244e which passes through the elastomer block 213, housed in an opening 210d of the casing, held by the closing flange 211.

[0147] [Fig. 18], is a cross-sectional view of the electrical machine 200 showing the loop circulation of air in the closed space 214 formed by the casing 210 and the closing flange 211.

[0148] The cooling of the air passing inside the discoid rotor 100 is achieved by a double heat exchange: • with the ambient air outside the machine 200 by following the webs of the casing 210 and the closing flange 211; • with the stator coolant 220,230 along the fins radial 228a,238a of the lids 228,238 of the carcasses 221,231.

[0149] The air expelled from the annular chamber 110c of the discoid rotor 100, through the air outlet openings 121 along the path 118c, makes the following symmetrical loops: • along the paths 214a, is divided into two flows; • according to paths 214b, crosses carcasses 221,231 in material withdrawals 221e6,231e6; • according to paths 214c, bypasses the stators 220,230 between the periphery of the stators and the casing fabric 210; • according to the paths 214d, it moves towards the center of the machine 200 along, on the left the radial fins 228a of the cover 228 and the casing fabric 210 and on the right the radial fins 238a of the cover 238 and the fabric of the closing flange 211; • according to the 214th path, bypasses the stators 220,230 in their internal openings; • is re-aspirated, according to path 118a through air inlets 117al,l 17b 1 of discoid rotor 1.

[0150] During the 214d paths, the stator cooling device 220,230 therefore participates in cooling the air circulating in the annular chamber 110c of the discoid rotor 100.

Claims

1. Demands Axial magnetic flux electric machine (200) composed of: • a central discoidal rotor (100) with a structure composed mainly of two flanges (110a, 110b) made of composite material and a peripheral steel ring 120 together forming an annular chamber 110c. The two flanges support rotor cores (130) generating a magnetic field, in a number of three and each surrounded by a coil (140). In the annular chamber (110c), under the coils, are arranged the electrical collectors (141, 142, 143, 144). Lateral air inlets (117a, 117b) in the annular chamber 110c and radial air outlets (121) in the peripheral ring (120) allow, when the rotor is rotated, a natural circulation of air to cool the coils; • Two lateral stators (220, 230) constructed on the basis of a frame (221, 231) made of composite material, comprising an outer ring (221e, 231e), an inner ring (221i, 231i), and a radial face (221r, 231r) with trapezoidal openings that accommodate the stator contacts (222, 232), a number of which is a multiple of two, separated from the rotor (100) by air gaps (241). They are connected to each other at the rear end by a yoke (227, 237) which completes the magnetic field loop. Each contact carries a coil (223, 233). They are supplied with direct current by closed circular collectors (224a, 224b, 234a, 234b) arranged inside the frames (221, 231) near the outer ring (221e, 231e). The frame (221, 231) is closed, opposite its radial face, by a cover (228, 238). Frame and cover form a sealed stator chamber (221v, 231v) in which a cooling fluid circulates; • a rotor power supply device (300) comprising rotating elements (320, 330, 340, 350) made of insulating material carrying ring-shaped plates (331, 341, 342, 351) made of conductive material, each having a tab (331u, 341v, 342w, 351n) for connection to the commutators (141, 142, 143, 144) by the power supply wires (151, 152, 153, 154), fixed elements (360, 370) made of insulating material carrying ring-shaped plates (361, 362, 371, 372) and each having a tab (361u, 362v, 371w, 372n) for connection to the external power supply, current-transmitting discs (380) interposed between the rotating and fixed ring-shaped plates, characterized in that: • the rotor coils (100) are supplied with three-phase alternating current via the variable-frequency power supply device (300), which allows for speed control of the electric machine. • The stator is supplied with direct current, which allows for torque and power control of the electric machine.

2. An axial magnetic flux electric machine (200) characterized in that in the rotor (100), one coil (140) out of three is connected to the commutator (141) corresponding to phase 1, to the commutator (142) corresponding to phase 2, to the commutator (143) corresponding to phase 3, and all the coils are connected to the commutator 4 corresponding to neutral. The coils of the same phase are connected in parallel.

3. An axial magnetic flux electric machine (200) characterized in that the stator coils (223, 233) are connected as follows: the ends of the wires (223a) are connected in parallel to the commutator (224a), and the ends of the wires (223b) are connected to the commutator (224b). Similarly, the ends of the wires (233a) are connected to the commutator (234a), and the ends of the wires (233b) are connected to the commutator (234b). In order to obtain that two adjacent coils deliver opposite magnetic fields, because the direction of wire winding is the same, it is necessary that two ends 223a be alternately adjacent to two ends 223b, and likewise, that two ends 233a be alternately adjacent to two ends 233b.

4. An axial magnetic flux electric machine (200) characterized in that two facing stator posts, one belonging to the left stator (220) and the other to the right stator (230), are connected to in order to obtain two magnetic fluxes in the same direction.

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