FR3080720A1 - ROTATING ELECTRIC MACHINE WITH A SYSTEM FOR MAINTAINING AN ELECTRICAL BEAM - Google Patents

Abstract

The invention relates mainly to a rotating electrical machine (10), in particular for a motor vehicle, comprising: - an electrical connector (41) having a signal interface, said electrical connector (41) being situated on a first axial side of said machine rotating electric motor (10), and - at least one sensor (40, 44), the sensor (40, 44) being located from a second axial side opposite to said first axial side and connected to the electrical connector (41) via an electrical harness (43), characterized in that said rotating electrical machine (10) further comprises a radial holding system (45) of the electrical harness (43) comprising a first holding portion (47) integral with the skirt (36) of the first bearing (15) and a second holding portion (48) integral with the skirt (36) of the second bearing (16).

Description

ROTATING ELECTRIC MACHINE PROVIDED WITH AN ELECTRIC BEAM HOLDING SYSTEM

The present invention relates to a rotary electrical machine provided with a system for maintaining an electrical harness.

In a manner known per se, rotary electrical machines comprise a stator and a rotor secured to a shaft. The rotor may be integral with a driving and / or driven shaft and may belong to a rotating electrical machine in the form of an alternator, an electric motor, or a reversible machine capable of operating in both modes.

The stator is mounted in a casing configured to rotate the shaft on bearings by means of bearings. The rotor comprises a body formed by a stack of sheets of metal sheets held in the form of a package by means of a suitable fixing system. The rotor has poles formed for example by permanent magnets housed in cavities formed in the magnetic mass of the rotor. Alternatively, in a so-called salient pole architecture, the poles are formed by coils wound around the rotor arms.

Furthermore, the stator comprises a body constituted by a stack of thin sheets forming a crown, the inner face of which is provided with notches open towards the inside to receive a winding. This winding is obtained for example from a continuous wire covered with enamel or from conductive elements in the form of pins linked together by welding.

The electric machine furthermore includes sensors, in particular a temperature sensor so as to be able to secure the electric machine in the event of overheating and a position sensor in order to be able to apply the current in the stator phases at the appropriate time. In certain configurations, the presence of the sensors on the opposite axial side with respect to a connector provided with a signal interface necessitates passing an electrical harness outside the rotary electrical machine.

In order to ensure that this beam is maintained, the document FR3052000 proposes using a cover capable of snapping onto a corresponding shape made in the bearings of the electric machine. However, such a configuration is not suitable for integrating the electric machine inside a gearbox-type host element, insofar as there is a risk that the harness for holding the electric harness detaches and damages the gearbox gears.

The present invention aims to effectively remedy this drawback by proposing a rotary electrical machine, in particular for a motor vehicle, comprising:

- a rotor mounted on a shaft,

- A stator provided with a body and a winding, said stator being mounted between a first bearing and a second bearing, at least one bearing comprising a bearing housing for guiding the shaft in rotation, the first and second bearings being each arranged at an axial end of the stator, each bearing comprising a transverse flange and an annular skirt of axial orientation,

an electrical connector having a signal interface, said electrical connector being located on a first axial side of said rotary electrical machine, and

- at least one sensor, the sensor being located on a second axial side opposite to said first axial side and connected to the electrical connector by means of an electrical harness, characterized in that said rotary electrical machine further comprises a system of radial maintenance of the electrical harness comprising a first one-piece holding portion with the skirt of the first bearing and a second one-piece holding portion with the skirt of the second bearing.

The invention thus makes it possible, thanks to the portions for holding the one-piece electrical harness with the skirt of the bearings, to avoid any risk of penetration of a foreign body inside a host element of the gearbox. The invention also makes it possible to produce the holding system in a simple, reproducible and economical manner without involving an attached part.

According to one embodiment, the first and second holding portions have an L-shaped section.

According to one embodiment, the holding portions are open towards one another.

According to one embodiment, the holding portions are aligned with respect to each other.

According to one embodiment, each holding portion projects axially with respect to the axial end edge of the skirt.

According to one embodiment, each holding portion extends axially up to an axial end edge of the skirt.

According to one embodiment, at least one piece of elastic material arranged around the electrical harness is intended to be inserted at least partially into a space delimited by a holding portion.

According to one embodiment, the electric bundle comprising several wires, the piece of elastic material is intended to hold the wires together.

According to one embodiment, the piece of elastic material extends axially so as to project axially relative to the skirt of the bearing with which the holding portion receiving said piece is associated and in the direction of the skirt of the other bearing.

According to one embodiment, said rotary electrical machine comprises a sensor for measuring the angular position of said rotor and a sensor for measuring the temperature of the machine.

According to one embodiment, said rotary electric machine comprises a system for axially holding the electric harness, said axial holding system being in one piece with the transverse flange of one of the bearings, the other bearing being devoid of an axial holding system.

According to one embodiment, in the assembled machine, the two holding portions are contiguous or spaced apart from each other by a length corresponding substantially to the section of the electrical harness.

According to one embodiment, in the assembled machine, the two holding portions overlap axially.

The invention will be better understood on reading the description which follows and on examining the figures which accompany it. These figures are given only by way of illustration but in no way limit the invention.

Figure 1 is a perspective view of a rotary electrical machine according to the present invention;

Figure 2 is a longitudinal sectional view of the rotary electrical machine according to the present invention;

Figure 3 is a perspective view of a bearing of the rotary electric machine according to the invention;

Figure 4 is a detailed view of the radial beam holding system according to the present invention;

FIG. 5 is a detailed perspective view of the electric harness ensuring the connection between a connector and the position and temperature sensors on board in the electric machine according to the invention;

Figure 6 is a detailed view of the axial holding system of the electric harness according to the present invention;

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

Figures 1 and 2 show a rotary electrical machine 10 comprising a polyphase stator 11 surrounding a rotor 12 mounted on a shaft 13 of axis X corresponding to the axis of the electrical machine 10. The stator 11 is separated from the rotor 12 by a air gap between the internal periphery of the stator 11 and the external periphery of the rotor 12. The stator 11 is mounted between a front bearing 15 and a rear bearing 16, the two bearings 15, 16 being each disposed at an axial end of the stator 11.

The bearings 15, 16 are assembled together by means of tie rods intended to cooperate with threaded holes 17 formed in the protruding ears of the bearings 15, 16, so that the stator 11 is mounted clamped between the two bearings 15, 16.

This electric machine 10 may be intended to be coupled to a gearbox belonging to a traction chain of a motor vehicle. The machine 10 is capable of operating in an alternator mode in particular to supply energy to the battery and to the on-board network of the vehicle, and in an engine mode, not only to ensure the starting of the engine of the vehicle, but also for participate in vehicle traction alone or in combination with the heat engine.

More specifically, as can be seen in FIG. 2, the rotor 12 comprises a body 19 in the form of a pack of sheets. Permanent magnets 20 are implanted in cavities 21 of the body 19. The magnets 20 may be made of rare earth or ferrite depending on the applications and the desired power of the electric machine 10.

Furthermore, the stator 11 comprises a body 23 constituted by a pack of sheets as well as a coil 24. The body 23 is formed by a stack of sheets of sheets independent of each other and maintained in the form of a pack by means of a suitable fixing system. The body 23 is provided with notches on its internal periphery for receiving the coil 24.

The electric machine 10 is cooled by means of a cooling circuit 26 allowing the flow of a cooling liquid, in this case oil, inside the machine 10. For this purpose, the circuit cooling 26 comprises a pump 27 conveying the oil in a central bore 28 produced in the shaft 13 and towards at least two orifices 29 opening out radially and arranged axially on either side of the rotor 12 to diffuse the coolant to inside the machine 10.

Such a configuration thus makes it possible to convey the coolant to the two axial end faces of the rotor 12. The cooling circuit 26 operates in a closed loop, so that the oil is taken up by the pump 27 in a reservoir. 30 and is recovered after circulation in the machine 10 in this tank 30. The tank 30 may correspond to the volume of oil contained in the gearbox.

In addition, the rotor 12 comprises two flanges 32 each pressed against an axial end face of the rotor 12. These flanges 32 provide an axial retention of the magnets 20 inside the cavities 21 and also serve to balance the rotor 12. Each flange 32 may advantageously be provided with at least one projection member 33, constituted by a blade, arranged to project by centrifugation the coolant arriving on the corresponding end face towards the chignon of the winding 24.

As can be seen in Figure 3, each bearing 15, 16 has a transverse flange 35 which extends in a plane perpendicular to the axis X1 of the bearing intended to be coincident with the axis X of the machine 10 In addition, an annular skirt 36 comes from the outer periphery of the flange 35. The skirt 36 has an axial orientation relative to the axis X1. At least one of the bearings 15, 16 comprises a bearing housing 37 for guiding the shaft 13 in rotation. The bearings 15, 16 also include through holes 38 for a cooling fluid.

As can be seen in FIG. 1, a position sensor 40 capable of measuring the angular position of the rotor 12 is mounted around the shaft 13. This sensor 40 is arranged on the side of the rear bearing 16. Furthermore, the electric machine 10 comprises an electrical connector 41 having a signal interface. This connector 41 is mounted on the front bearing 15, that is to say on the opposite axial side with respect to the sensor 40 mounted on the rear bearing 16. The sensor 40 is connected to the signal interface of the connector 41 by the via an electrical harness 43. The temperature sensor 44 is also connected to the signal interface of the connector 41 via the harness 43.

As shown in FIGS. 1 and 4, a retaining system 45 ensures radial maintenance of the electrical harness 43 which extends along the outer periphery of the skirts 36. This retaining system 45 comprises a first retaining portion 47 monobloc with the skirt 36 of the front bearing 15 and a second holding portion 48 monobloc with the skirt 36 of the rear bearing 16. By monoblock, it is meant that a holding portion 47, 48 is molded or fixed in a non-removable connection , in particular by welding, with a skirt 36 of the corresponding bearing 15, 16.

The first and second holding portions 47, 48 have an L-shaped section. The holding portions 47, 48 are open towards one another. Thus, each holding portion 47, 48 comprises a wall 50 extending, in cross section, radially with respect to the axis X and a wall 51 extending in a circumferential direction. The walls 51 of the parts of the holding portions 47, 48 are directed towards one another while being offset axially with respect to each other.

Advantageously, the holding portions 47, 48 are aligned with respect to each other. In addition, an axial length of the holding portions 47, 48 is at least equal to three times the diameter of the electrical harness 43 in order to ensure effective axial guidance of the harness 43 along the machine 10.

In the embodiment shown, each holding portion 47, 48 projects axially relative to the axial end edge of the skirt 36. As a variant, each holding portion 47, 48 extends axially up to an edge d axial end of the skirt 36. In this case, the axial end of each holding portion 47, 48 is flush with the end of the skirt 36, without exceeding it axially.

Furthermore, as shown in FIG. 5, two pieces of elastic material 52, for example rubber, arranged around the bundle 43 are intended to be inserted at least partially in a space delimited by a holding portion 47, 48. The bundle 43 comprising several wires, the parts 52 make it possible to hold the wires together.

To improve the retention of the beam 43, an elastic piece 52 has an external diameter greater than the state not contained at the height measured between the skirt 36 and the wall 51 of a holding portion 47, 48.

The piece of elastic material 52 may extend axially so as to project axially with respect to the skirt 36 of the bearing 15, 16 with which is associated the holding portion 47, 48 receiving said piece 52 and in the direction of the skirt 36 of the other bearing 15, 16.

In the assembled machine, the two holding portions 47, 48 are contiguous or spaced apart from each other by a length substantially corresponding to the section of the electrical harness 43. Alternatively, the two holding portions 47, 48 overlap axially one by compared to each other.

The electric machine 10 may also include an axial holding system 54 of the electric harness 43, as shown in FIGS. 1 and 6. The axial holding system 54 is in one piece with the transverse flange 35 of the rear bearing 16, the another bearing 15 being devoid of an axial holding system.

The axial holding system 54 comprises two studs 55 positioned on either side of the electrical harness 43 and ensuring axial retention of the electrical harness 43. In the example shown, the studs 55 guide a bent portion of the bundle sensor 43. The studs 55 each comprise a head 56 formed by a recess 57 and against which the electric harness 43 comes to bear to prevent axial displacement of the beam 43 relative to the axis X. The studs 55 are spaced apart from one another along the path of the electric beam 43. The hollows 57 of the studs 55, which have a dimension corresponding to that of the beam 43, are turned towards one another.

A third hollow pad 58 guides the electrical harness 43 connected to the temperature sensor 44.

Of course, the foregoing description has been given by way of example only and does not limit the scope of the invention from which one would not depart by replacing the various elements with any other equivalent.

Furthermore, the various features, variants, and / or embodiments of the present invention can be combined with one another in various combinations, insofar as they are not incompatible or mutually exclusive of one another.

Claims (13)

1. Rotating electric machine (10), in particular for a motor vehicle, comprising: - a rotor (12) mounted on a shaft (13), - a stator (11) provided with a body (23) and a winding (24), said stator (11) being mounted between a first bearing (15) and a second bearing (16), at least one bearing ( 15, 16) comprising a bearing housing (37) for guiding the shaft (13) in rotation, the first and second bearings (15, 16) being each disposed at an axial end of the stator (11), each bearing (15, 16) comprising a transverse flange (35) and an annular skirt (36) of axial orientation, an electrical connector (41) having a signal interface, said electrical connector (41) being located on a first axial side of said rotary electrical machine (10), and - at least one sensor (40, 44), the sensor (40, 44) being located on a second axial side opposite to said first axial side and connected to the electrical connector (41) by means of an electrical harness (43 ), characterized in that said rotary electrical machine (10) further comprises a radial holding system (45) of the electrical harness (43) comprising a first holding portion (47) integral with the skirt (36) of the first bearing ( 15) and a second holding portion (48) integral with the skirt (36) of the second bearing (16). 2. Rotating electric machine according to claim 1, characterized in that the first and the second holding portions (47, 48) have an L-shaped section. 3. Rotating electric machine according to claim 1 or 2, characterized in that the holding portions (47, 48) are open towards one another. 4. Rotating electric machine according to any one of claims 1 to 3, characterized in that the holding portions (47, 48) are aligned with respect to each other. 5. Rotating electric machine according to any one of claims 1 to 4, characterized in that each holding portion (47, 48) projects axially with respect to the axial end edge of the skirt (36). 6. Rotating electric machine according to any one of claims 1 to 4, characterized in that each holding portion (47, 48) extends axially up to an axial end edge of the skirt (36). 7. rotary electrical machine according to any one of claims 1 to 6, characterized in that at least one piece of elastic material (52) disposed around the electrical harness (43) is intended to be inserted at least partially in a space delimited by a holding portion (47, 48). 8. Rotating electric machine according to claim 7, characterized in that the electric bundle (43) comprising several wires, the piece of elastic material (52) is intended to hold the wires together. 9. rotary electric machine according to any one of claims 7 to 8, characterized in that the piece of elastic material (52) extends axially so as to project axially relative to the skirt (36) of the bearing (15 , 16) which is associated with the holding portion (47, 48) receiving said part (52) and in the direction of the skirt (36) of the other bearing. 10. Rotating electric machine according to any one of claims 1 to 9, characterized in that it comprises a sensor for measuring the angular position (40) of said rotor (12) and a temperature measurement sensor (44) of the machine. 11. Rotating electric machine according to any one of claims 1 to 10, characterized in that it comprises an axial holding system (54) of the electric harness (43), said axial holding system (54) being in one piece with the transverse flange (35) of one of the bearings (15, 16), the other bearing being devoid of an axial holding system (54). 12. Rotating electric machine according to any one of claims 1 to 11, characterized in that in the assembled machine, the two holding portions (47, 48) are contiguous or spaced apart from each other by a length substantially corresponding to the section of the electrical harness (43). 13. rotary electric machine according to any one of claims 5 to 11, characterized in that in the assembled machine, the two holding portions (47, 48) overlap axially.