FR3037446A1 - DEVICE FOR ELECTRICAL CONNECTION BETWEEN AN ELECTRIC MOTOR AND A POWER SUPPLY UNIT OF THE MOTOR, IN PARTICULAR FOR A MOTOR VEHICLE COMPRESSOR - Google Patents

Abstract

The invention relates to a device for electrical connection between an electric motor and a power supply unit of said motor, in particular for a motor vehicle compressor, said device comprising a connection plug (62) formed in a flexible metal sheet configured to allow a mounting blinding the motor on the power unit with mechanical contact and electrical connection between said connector plug (62) and a connector (52) of said power supply unit.

Description

The invention relates to a device for electrical connection between an electric motor and a power supply unit of said motor. It also relates to a motor equipped with said device and an assembly formed of said motor and its power unit. It will find more particularly its applications in the field of compressors, particularly electric compressors, for example for the circulation of a refrigerant inside a vehicle air conditioning system. An electric compressor typically comprises a compression mechanism, driven by an electric motor, to pressurize the coolant in the air conditioning circuit. To power the electric motor, the compressor further comprises an inverter for converting the available current into a current suitable for the compressor motor. By way of example, the inverter is adapted to convert a direct current into a three-phase alternating current.

Different solutions based on wired mounting have been proposed to establish an electrical connection between the motor and the inverter. However, such solutions are difficult to adapt to in case of low voltage power supply current and high amperage. Indeed, in this case, it is necessary to use son of large section and it is not possible to use connectors allowing a simple mounting of the motor on the inverter. The invention proposes to overcome the aforementioned drawbacks and concerns for this purpose a device for electrical connection between an electric motor and a power supply unit of said motor, in particular for a motor vehicle compressor, said device comprising a connection plug formed in a flexible metal sheet configured to allow blind mounting of the motor on the power unit with mechanical contact and electrical connection between said connector plug and a connector of said power unit.

3037446 2 Thanks to the use of a conductor defined in a metal sheet, it is possible to have a connection plug with a large cross-section, in a limited space requirement. In addition, it is possible to form said connection plug so that it allows blind mounting. In addition, because of the small size of said plug, it limits the pressure losses in the event of fluid circulation around the engine, as is the case in an electric compressor for a motor vehicle. By the flexible nature of the sheet, there will also be a solution for resisting vibration effectively.

According to additional features of the invention which may be taken together or separately: said device comprises a conductor, intended to be electrically connected to several windings of the motor, said connection plug is electrically connected to said conductor, said conductor consists of a metal sheet, - said metal sheet is ring-shaped, - said sheet metal has a substantially rectangular cross section, - said device is configured so that a large side of the cross section of said sheet metal metal being intended to be oriented along a longitudinal axis of a rotor of said motor, after assembly, - said device comprises pins, electrically connected to said conductor, each of said pins being intended to be connected to one of the windings of the motor, 25 - The said pins are L-shaped, one of the branches of the L being orien radially and the other of the branches of the L being intended to be oriented along said longitudinal axis of the rotor of the engine, after assembly, - said device comprises a plurality of said conductors, each associated with a said plug, 30 - said drivers are arranged in a concentric manner, - said connection plugs are angularly offset from one to the other of the conductors, - said plugs are located in the same angular sector of less than 900, or even 45 °, or even 30 ° , - The connection plugs have a different angular orientation, - The one or more connectors and the one or more connection plugs are overmoulded, in particular of an electrical insulating material, to form a unitary assembly, 5 - Said plug connector comprises a contact portion with the connector of the power supply unit and a connecting portion configured to provide flexibility to the mechanical contact established in being said device and said power supply unit, - said connecting portion comprises a lyre-shaped zone, 10 - said contact portion is configured to allow the establishment of said mechanical contact in a translational movement along the longitudinal axis of the rotor of said motor, - said contact portion comprises an end intended to come into touching contact with the connector of said connecting unit, 15 - said contact portion comprises one or more flanks intended to come into contact with a side wall of the connector of said connecting unit, - said flanks are located at a bent zone of said contact portion, - said contact portion is configured to allow mounting in a translational and rotational movement, - said contact portion comprises a housing for engagement of the connector of the feeding unit in translation movement along the longitudinal axis of the rotor of said motor, - Lad said contact portion comprises a blocking housing of the connector of the supply unit, said engagement housing and said blocking housing communicate with each other so as to allow the passage of the connector of the supply unit of the power supply unit; to each other in a rotational movement about the longitudinal axis of the rotor of said motor, said contact housing comprises concave areas configured to allow multipoint contact with the connector of said power unit.

The invention also relates to a motor provided with a connection device as described above and an assembly formed of said motor and its power supply unit.

According to additional features, which may be taken together or separately: said connector comprises a connection plug; said connector plug of the power supply unit comprises a core made of a first metallic material and a skin made of a second metallic material, - said first material is copper. According to one aspect of the invention, said assembly further comprises a compressor, driven by said motor, so as to form an electric compression device. The invention will be better understood on reading the description which will follow, given solely by way of example, and referring to the appended drawings in which: FIG. 1 is a longitudinal sectional view of a compression device according to the invention, - Figure 2 is a cross-sectional view of a portion of the engine and the connection device of the compression device of Figure 1, in a position where the engine is being assembled on its unit FIG. 3 is a perspective view, FIG. 5 schematically illustrates, in axial view and after flattening, a conductor and a connection plug, FIG. of the connection device of the preceding figures, - Figure 6 illustrates a longitudinal sectional view of an alternative embodiment of the connection plug of the connection device according to the invention. As illustrated in FIG. 1, the invention relates to a compression device. Figure 1 must therefore show at least schematically that the end of the shaft 3037446 5 drives a compression system. The latter can be used for the compression of fluids of different kinds and can be mounted on any type of mobile device as well as fixed. It is however more particularly intended for the circulation of a refrigerant inside an air conditioning circuit of a motor vehicle on the chassis of which it will be fixed, directly or indirectly. Said electric compression device according to the invention comprises a compressor, not shown, a motor or electric machine 3 for driving the compressor and a device 5 for converting current, mounted on said machine. Said conversion device 5 is configured to allow the supply and control of said electric machine 3. It thus serves as a power supply unit of the engine.

The compressor is advantageously of the spiral compression type (Scroll in English) or the paddle type or the piston type, these examples being given for illustrative purposes without limiting the scope of the invention. Said electric machine 3 is, for example, a three-phase electric motor. Said conversion device 5 is, for example, an inverter, namely a device for converting a direct current, for example delivered by a battery, into an alternating current, in particular a three-phase alternating current. The compressor may comprise a housing in which compression members are housed. The electrical machine 3 comprises a housing 30 in which are housed a stator 34 and a rotor 32 of said electric machine. Said housings are, in particular, of hollow cylindrical shape. They extend longitudinally along a longitudinal axis common to a shaft of said compressor and the rotor of said electric machine. The compressor housing and / or the housing 30 of the electrical machine are, for example, aluminum or aluminum alloy. Said electric machine 3 is advantageously configured to be fixed on a support, in particular the chassis, the drive motor or the gearbox of the equipped vehicle. The stator 32 comprises a body 36 provided with teeth 3037446 6 38 spaced angularly from each other and having between them notches 40. The body 36 of said stator 32 is formed, for example, by stacking a package of sheets. Said stator 32 further comprises windings 42, located around each of the teeth 38 and occupying said notches 40. Said 5 windings 42 are advantageously connected to each other in a three-phase configuration in .Triangle and triangle (because no neutral points) (it Both of these types of connections must be provided by said compression device, which is preferably configured so that the refrigerant passes through said electrical machine 3 by coming into contact with said conversion device 5 so as to cool them down. between said electric machine 3 and the compressor 1.

Said conversion device 5 comprises a body 50, configured to be mounted on the electric machine 3. In other words, said body 50 of the conversion device and said housing 30 of the electric machine 3 are two separate parts reported to each other. 'other.

Said conversion device 5 is here mounted cantilevered on said electric machine 3. It has, for example, a cylindrical configuration, in particular coaxial with the casings of the compressor and / or of the electric machine 3.

Said conversion device comprises, in particular, current conversion means, not shown, housed in said body 50. Said conversion means may comprise, for example, bridges of transistors mounted on printed circuit boards. Said device also comprises electrical connectors 52 for feeding said electrical machine 3, here three for the three-phase power supply. This is, for example, connection plugs in the form of substantially rectilinear rods, in particular arranged at the top of a triangle.

The said body 50 is advantageously monobloc, especially from a foundry. It may be configured to promote cooling of said conversion means.

The power supply network for powering the electric machine is here provided at a relatively low voltage, for example less than 60V, involving the use of currents with high amperage, especially peaks. According to one aspect of the invention, a device 60 for electrical connection 10 between the electric motor 3 and the power supply unit 5 of said motor is provided. It is in this way located between said electric motor 3 and said power supply unit 5. Said connecting device 60 comprises one or more connection plugs 62a, 62b, 62c, here three, namely one for each phase of the motor well 15 that in Figure 1, only one of said connection plugs 62 is visible. Said connection plugs are intended to allow the circulation of an electric current for supplying the motor from said power supply unit 5. They are each formed in a flexible metal sheet. They are further configured to allow blind mounting of the motor to the power supply unit with mechanical contact and electrical connection between each connector plug 62 and the associated connector 52, as will be discussed in more detail below. As illustrated in FIGS. 2 and 3, said device comprises one or more conductors 64a, 64b, 64c, here three, namely one for each phase of the motor, intended to be electrically connected to several of the windings 42 of the motor. Each connection plug 62a, 62b, 62c is electrically connected to one of said leads 64a, 64b, 64c. Said conductors 64a, 64b, 64c are each constituted by a metal sheet bus bar. Said metal sheet is here in the form of a ring. It may have a rectangular cross section. Said connection plugs 62a, 62b, 62c are advantageously angularly offset from one another to the conductors 64a, 64b, 64c. They are 3037446 8 here located in the same angular sector less than 90 °, or even 45 °, or even 30 °. As best seen in FIG. 1 (or 4), said device is configured so that a large side of the cross section of said metal sheet is oriented along a longitudinal axis of the rotor 32 of said motor, after mounting. As can also be seen in FIG. 1, said conductors 64a, 64b, 64c and said one or more connection plugs are overmolded with an electrical insulating material 68, to form a unitary assembly, here having the configuration of a crown, centered on one end of the rotor 32. As shown in FIG. 4, said device may comprise pins 66, electrically connected to said conductor 64a, 64b, 64. Each of said pins 66 is intended to be connected to one of the windings 42 of the motor 3. Said pins 66 are L-shaped here, one of the branches of the L being oriented radially and the other of the branches of the L being oriented along said longitudinal axis of the rotor 32 of the engine 3, after assembly. The radial branches are fixed, in particular brazed and / or welded, to one of the conductors 64a, 64b, 64c while the other branches are attached to one end of the windings 42. The motor here comprises fifteen windings 42 and for the desired mounting, each lead 64a, 64b, 64c is connected to ten windings 42 of the motor 3 by one of said pins 66. Said leads 64a, 64b, 64c are arranged, for example, concentrically. Each connection plug 62a, 62b, 62c includes a contact portion 70 with the associated connector 52a, 52b, 52c of the power unit and a connecting portion 72 configured to provide flexibility for mechanical contact established between said device and said power supply unit 5. Said connecting portion 72 comprises a radial portion, connected to the conductors 64a, 64b, 64c, and an angularly extending portion, located between said radial portion and said contact portion 70 Said connecting portion 72, in particular said portion portion extending angularly, may include a zone 74 in the form of lyre to enhance its flexibility.

Said contact portion 70 is preferably configured to allow mounting in a translational and rotational movement also called bayonet mounting. Said contact portion 70 comprises a housing 75 for engaging the connector 52 of the power supply unit in a translation movement along the longitudinal axis of the rotor of said motor. Said contact portion 10 further comprises a housing 76 for blocking said connector 52. Said engagement housing 75 and said blocking housing 76 communicate with each other so as to allow the passage of the connector 52 of the power supply unit. to one another in a rotational movement about the longitudinal axis of the rotor of said motor.

In other words, said engagement housing 75 translational guide said connectors 52a, 52b, 52c during a first phase of the movement, as illustrated in FIG. 2, then, by rotation according to the arrow marked 78, said connectors are respectively introduced into said housing 76 blocking the connection plugs 62a, 62b, 62c. Said engagement housing 75 and said blocking housing 76 are herein defined by an omega shape of the contact portion 70, respectively by the open portion and bottom of said omega shape. Such an omega 25 form allows snap locking of the connectors 52a, 52b, 52c in said connection plugs 62a, 62b, 62c. After locking, studs, not shown, may be used to lock in rotation the housing 30 of the motor and the body 50 of the feed unit, said studs being introduced into the orifices of each of these parts, said orifices being then in vis-à-vis.

To allow limited angular space, the connection plugs 62a, 62b, 62c advantageously have a different angular orientation. Here, the connection plugs 62a, 62c of the inner and outer conductors 64a, 64c are oriented in a sense that can be described as anti-clockwise while the connecting plug 62b of the intermediate conductor 62b is oriented in one direction. which can be described as a timetable. Moreover, said connection sheets may be of different configuration. Here, the connection plugs 62a, 62c of the internal and external conductors 64a, 64c are identical in configuration with a substantially plane connection portion 72 on either side of the lyre-shaped zone 74, in its portion s'. extending angularly, while the connection plug 62b of the intermediate conductor 64b has a different configuration with a substantially rounded connecting portion 72, in its portion extending angularly. It may further be noted that one of the two plugs 10 for connecting the inner and outer conductors 64a, 64c, here the external plug 62a is angularly between the other 62c of said two plugs and the third plug 62b. As illustrated in FIG. 5, said blocking housing 76 comprises concave zones 80 configured to allow multipoint contact with the associated connector 64 of said power supply unit 5. Said concave zones 80 are here distributed approximately at 900 each. the other. To further promote contact, a distal end of said connection plugs may include teeth 82 spaced apart from each other along said connectors 52a, 52b, 52c (see FIG. 4). As illustrated in FIG. 6, in a variant, said contact portion 70 is configured to allow the establishment of said mechanical contact in a translational movement along the longitudinal axis of the rotor of said motor, according to the arrow marked 84. In other words, said contact portion 70 provides both a guiding of said connectors 52 and a contact therebetween with said pins 62. Said contact portion 70 includes an end 86 for touching the connector 52 of said unit link. Said contact portion 70 also comprises one or more flanks 88 intended to come into contact with a side wall 90 of the connector 52 of said linking unit. Said flanks 88 are located at a bent zone of said contact portion 70.

In this particular configuration, it is advantageous that the connectors 52 of the power supply unit 5 comprise a core 92 made of a first metallic material, for example copper, and a skin 94 made of a second metallic material, for example. example of steel. It is understood that, in these two modes, a blind assembly of the motor 3 and its supply unit 5 on one another is possible, as well as its disassembly. Furthermore, the use of a sheet formed of a metal sheet, for example a copper alloy for contact, makes it possible to have both good flexibility and a section of current flow which is significant. while remaining limited space. The vibration resistance offered by the use of a sheet, possibly reinforced by the forms of lyre which it may be provided, is another advantage of the invention. 15

Claims (13)

REVENDICATIONS1. Electrical connection device between an electric motor (3) and a power supply unit (5) of said motor (3), in particular for a motor vehicle compressor, said device comprising a connection plug (62) formed in a flexible metal sheet configured to allow blind mounting of the motor on the power supply unit (5) with mechanical contact and electrical connection between said connection plug (62) and a connector (52) of said power supply unit (5). 2. Device according to claim 1 comprising a conductor (64), intended to be electrically connected to several windings (42) of the motor (3) and wherein said connection plug (62) is electrically connected to said conductor (64). 3. Device according to the preceding claim wherein said conductor (64) consists of a metal sheet, ring-shaped. 4. Device according to the preceding claim wherein said metal sheet has a rectangular cross section, a large side of the cross section of said metal sheet being intended to be oriented along a longitudinal axis of a rotor (32) of said motor (3). , after assembly. 5. Device according to any one of claims 2 to 3 comprising pins (66), electrically connected to said conductor (64), each of said pins (66) being intended to be connected to one of the windings (42) of the engine (3). 6. Device according to any one of claims 2 to 4 comprising a plurality of said conductors (64a, 64b, 64c), each associated with a said plug (62a, 62b, 62c). 3037446 13 7. Device according to the preceding claim wherein said conductors (64a, 64b, 64c) are arranged concentrically. 8. Device according to any one of claims 6 or 7 wherein said connection plugs (62a, 62b, 62c) are angularly offset from one another to the conductors (64a, 64b, 64c). 9. Device according to any one of claims 2 to 8 wherein said one or more conductors (64) and said one or more connection plugs (62) are overmolded to form a unitary assembly. Apparatus according to any one of the preceding claims wherein said connection plug (62) comprises a contact portion (70) with the connector (52) of the power supply unit (5) and a connecting portion (72) configured to provide flexibility for mechanical contact established between said device and said power supply unit (5). 11. Device according to claim 10 wherein said contact portion (70) comprises an engagement housing (75) of the connector (52) 20 of the power unit (5), in a translational movement, and said contact portion comprises a housing (76) for locking the connector (52) of the power supply unit (5), said engagement housing (75) and said locking housing (76) communicating with each other so as to allow the passage of the connector (52) of the supply unit (5) from one to the other 25 in a rotational movement, said contact portion being configured to allow mounting in a translational and rotational movement . 12. Device according to the preceding claim wherein said locking housing (76) comprises concave zones (80) configured to allow multipoint contact with the connector (52) of said power supply unit (5). 3037446 14 13. An assembly of a motor, equipped with the connection device according to any one of the preceding claims, and the power unit of said motor.