WO2021155890A1

WO2021155890A1 - Electrical machine of a motor vehicle

Info

Publication number: WO2021155890A1
Application number: PCT/DE2021/100115
Authority: WO
Inventors: Holger Schwab
Original assignee: Brose Fahrzeugteile SE & Co. Kommanditgesellschaft, Würzburg
Priority date: 2020-02-07
Filing date: 2021-02-05
Publication date: 2021-08-12
Also published as: CN115066828A

Abstract

The invention relates to an electrical machine (4) of a motor vehicle, said electrical machine comprising an electric motor (16) and an electronics compartment (18) having a printed circuit board (40) located therein and having a phase connection (44) which is fixedly held inside the electronics compartment (18) and is electrically contacted with a stator winding (50) of a stator (32) of the electric motor (16), wherein a bridge circuit (42) is supported on an upper side (60) of the printed circuit board (40), the printed circuit board (40) has a contact element (56) which is used to establish electrical plug-in contact for the phase connection (44), and the plug-in contact is established on an underside (58) of the printed circuit board (40) opposite the upper side (60).

Description

description

Electric machine of a motor vehicle

The invention relates to an electrical machine of a motor vehicle, having an electric motor and an electronics compartment with a printed circuit board arranged therein and with a phase connection held in place within the electronics compartment. The invention further relates to a refrigerant drive, in particular egg NEN refrigerant compressor of a vehicle air conditioning system, with such an electrical machine's rule.

In motor vehicles, air conditioning systems are regularly installed, which air conditioning the vehicle interior with the help of a refrigerant circuit forming system. Such systems basically have a circuit in which a refrigerant is guided. The refrigerant is heated in an evaporator and compressed by means of a (refrigerant) compressor or compressor, where the refrigerant then releases the absorbed heat via a heat exchanger before it is returned to the evaporator via a throttle. In such applications, scroll machines, for example, are basically possible as compressors or compressors for the refrigerant. Such scroll compressors typically have two scroll parts which can be moved relative to one another and which operate in the manner of a positive displacement pump. The compressor is driven, for example, by means of a belt drive from an internal combustion engine of the motor vehicle. If the air conditioning system is part of a motor vehicle that does not include an internal combustion engine, the refrigerant compressor typically has an electrical machine as an electric or electromotive drive, by means of which the compressor is driven. Here, the speed of the drive and thus the cooling capacity of the air conditioning system is set based on a temperature setting by a user of the motor vehicle or a realized temperature of the high-voltage battery.

The electric motor of the electric machine is usually brushless and is connected to electronics for control and / or regulation, the individual electric coils being energized in particular by means of a bridge circuit on a printed circuit board of the electronics. Here, electrical coils of the electric motor or its stator are electrically contacted, for example by means of phase connections, which in turn are electrically contacted with the bridge circuit. This has semiconductor switches that are operated by means of a PWM control. To protect against environmental influences (dirt, moisture), the motor or power electronics are usually housed in an electronics compartment of an (electronics) housing.

A comparatively high output of the electric motor is necessary for a fast and reliable start-up and operation of the compressor. In other words, comparatively large (rotary) currents are necessary to drive the rotor, since the compressor can be accelerated to an operating speed in a short time. With such a high power requirement and comparatively low speeds, the resulting electrical currents required are comparatively large. As a result, phase connections and the conductor tracks of the circuit board must be designed to be comparatively robust.

The invention is based on the object of specifying a particularly suitable electrical machine which is improved in particular with regard to mechanically robust electrical contact between a phase connection and a circuit board that is compact in terms of installation space. The invention is also based on the object of specifying a particularly suitable electric refrigerant drive. With regard to the electric machine, the object is achieved according to the invention with the features of claim 1 and with regard to the electric refrigerant drive with the Merkma len of claim 10. Advantageous refinements and developments are the subject of the subclaims.

The electric machine is part of a motor vehicle and has an electric motor that operates as a generator or as an electric motor. For example, the electric motor is used to drive the motor vehicle, which is therefore in particular an electric vehicle or a hybrid vehicle. Preferably, however, the electrical machine is part of an auxiliary unit of the motor vehicle, for example an adjustment drive, such as a steering motor, a so-called power steering, an electric window lifter or an electric seat adjustment. The electrical machine is suitably electrically contacted in the assembled state with an on-board network of the motor vehicle and is energized by means of it. In particular, the electrical machine is suitable for this. For example, the vehicle electrical system is a low-voltage electrical system and carries, for example, an electrical voltage of 12 volts, 24 volts or 48 volts. As an alternative to this, the electrical voltage that is applied to the electrical machine during operation or that the vehicle electrical system has, is 288 volts, 450 volts, 650 volts or 830 volts.

Particularly preferably, the electrical machine is a component of a refrigerant telantriebs, which is thus an electric or electromotive refrigerant drive. The electric refrigerant drive, as an electric refrigerant compressor (eKMV), is in particular a component of a refrigerant circuit of the motor vehicle, by means of which, for example, the interior of the motor vehicle is heated during operation and / or an energy storage device of the motor vehicle is cooled. In particular, the electric refrigerant drive comprises a compressor or compressor head, for example a scroll compressor. A refrigerant, for example a chemical refrigerant such as R134a or R1234yf, is particularly preferably compressed by means of the electric refrigerant drive. Alternatively, C02 is used as the refrigerant. The electric motor of the electric machine is preferably designed to be brushless, for example as a brushless direct current motor (BLDC). The electric motor thus has a stator with at least one electric coil as the stator winding, by means of which an electromagnet is at least partially formed. The stator preferably comprises a number of such electrical coils, for example two, three, six, or twelve, the electrical coils preferably being connected to electrical phases of the electric motor, for which they are suitably electrically contacted with one another in a parallel or series connection. The electrical phases themselves are in particular electrically contacted with one another in a delta or star circuit. The electric motor is preferably designed to be three-phase, six-phase or twelve-phase.

The current is supplied to the stator winding or the electrical voltage applied to the stator winding is tapped off by means of a printed circuit board, which is in particular part of an electronics unit. Here, the stator winding is electrically contacted with a bridge circuit of the printed circuit board. The circuit board preferably has a carrier which is made in particular from a fabric, for example a glass fiber fabric, or paper, which is preferably surrounded by a matrix that is, for example, epoxy or at least comprises this. In particular, conductor tracks are connected to the carrier and / or embedded therein. The conductor tracks themselves are, for example, created from a copper.

The bridge circuit preferably has four, six or twelve bridge branches and is consequently a B4, B6 or B12 circuit. In each case two bridge branches are assigned to one of the electrical phases of the electric motor, and / or the bridge circuit is preferably led to a direct current side, which is in particular electrically contacted with the vehicle electrical system. The conjunction “and / or” is to be understood here and below in such a way that the features linked by means of this conjunction can be designed both together and as alternatives to one another. Each of the bridge branches has, in particular, a semiconductor component, in particular a semiconductor switch, and preferably a power semiconductor switch. In particular, with the circuit board is a Power electronics provided or the circuit board is part of the power electronics.

The electrical machine has an electronics compartment which is, for example, part of a housing of the electrical machine. In particular, the housing / electronics compartment is made of a metal, for example aluminum or an aluminum alloy. The housing is preferably made as a die-cast part. The circuit board is arranged inside the electronics compartment, the stator, and in particular the stator winding, being located outside the electronics compartment. In particular, the circuit board is arranged parallel to a housing wall. The electronics compartment itself is preferably airtight and pressure-tight in the assembled state, which is why damage to the circuit board is essentially excluded.

The electrical machine has, for example, a bolt-shaped or pin-shaped phase connection (phase pin) which is in electrical contact with the stator winding of the stator. The phase connection is thus in particular a connection to one of the electrical phases of the stator, provided the electrical machine has several phases. The phase connection is held in place within the electronics compartment. For example, the phase connection is attached to a wall of the electronics compartment. By means of the phase connection, electrical contact is thus made through a wall of the electronics compartment, with at least one section of the phase connection being stationary at a defined, specific position within the electronics compartment. The phase connection is in particular rigidly attached to a housing wall of the electronics compartment.

The circuit board or its carrier has an upper side and a lower side as flat surfaces. The bridge circuit is worn and contacted with the conductor tracks on the upper side facing the stator or the housing wall. The circuit board here has a contact element for plug contact with the phase connection. In other words, the phase connection is electrically plug-in contact with the circuit board by means of the contact element. The contact element itself is electrical with the bridge circuit of the circuit board contacted, for example by means of a conductor track. The contact element is preferably rigidly connected to other components of the circuit board, in particular on the carrier of the circuit board. The contact element is designed as a plug-in power supply element or as a plug-in high-current contact, and is particularly suitable, preferably provided, to carry electrical currents of more than 100 amps, 150 amps or 200 amps, with the current carrying capacity, for example, less than 1,000 amps, 900 amps or 800 amps.

According to the invention, it is provided here that the plug-in contacting, that is to say the joining and electrical contacting, takes place on the underside of the printed circuit board facing the stator. In other words, the circuit board is contacted with the phase connection by means of the contact element on the circuit board side arranged opposite the bridge circuit. This means that the structural height of the contact element is oriented in the direction of the phase connection, as a result of which the space requirement on the surface having the bridge circuit is reduced. As a result, a particularly suitable and compact electrical machine is realized.

The stator is preferably arranged inside the housing and, for example, is designed essentially as a hollow cylinder. The electronics compartment is preferably located on the front side of the hollow cylindrical stator. In particular, the stator surrounds a rotor on the circumference, which is also positio ned within the housing and is rotatably mounted about an axis of rotation. The rotor itself has a number of permanent magnets, for example. When the electric motor is operated by an electric motor, in particular the electric coil of the stator winding, preferably the number of electric coils, is energized by means of the printed circuit board, so that a rotating magnetic field is provided. By means of a magnetic interaction between the permanent magnet (s) of the rotor and the electromagnet (s) of the stator, which is / are formed by means of the electrical coil (s), the rotor is set in a rotational movement around the axis of rotation. For example, a compressor or compressor head is connected to the rotor, provided the electrical machine is part of one Is refrigerant drive. The compressor is preferably located on the side of the stator opposite the electronics compartment.

The phase connection and the contact element are preferably made from a metal, in particular from the same material, for example from a copper material, which reduces any electrical resistances of the electrical contact.

In an expedient embodiment, the electrical (plug-in) contact is made perpendicular to the underside. In other words, the phase connection is essentially inserted vertically into the contact element. The vertical or normal direction is oriented essentially parallel to the axial direction of the electric motor or stator. A particularly simple and expedient contacting is thereby implemented, which simplifies the assembly and manufacture of the electrical machine.

In a suitable development, the electrical contact between the contact element and the phase connection takes place in a contact plane which is spaced parallel to a printed circuit board plane of the printed circuit board. This means that the contact point of the electrical contact between the contact element and the phase connection is arranged at a distance from the underside of the printed circuit board. The phase connection and the contact element are preferably rigidly connected to other components of the electrical machine, in particular to a housing wall of the electronics compartment or to the printed circuit board. Due to the contact plane or contact point spaced from the circuit board, an (axial) tolerance compensation is created when these two components move relative to one another during operation, which is why an electrical connection between the two connections is always guaranteed even in the worst case, for example if one of the two components is deformed in comparison to the other component due to a pressure or an introduction of heat. Tolerance compensation is also available during assembly, which is why the individual components can be manufactured with a comparatively large manufacturing tolerance, which reduces manufacturing costs. In a preferred embodiment, the contact element is designed as a plug socket, in particular as an SMD plug socket, that is to say as a surface-mounted device (SMD) socket. This means that the contact element is soldered directly onto the circuit board by means of solderable connection surfaces. This ensures particularly simple assembly and contacting of the contact element with the circuit board. The phase connection acts as a mating connector to the socket.

The contact element is designed, for example, in the shape of a cage with a number of flexurally elastic struts which, in the plug-in contact state, are clamped against the phase connection with a mechanical prestress. Due to the flexurally flexible struts, the contact element is designed to be flexible along a transverse direction oriented transversely to the insertion direction, which is why the electrical connection between the contact element and the phase connection is essentially flexible. In this embodiment of the contact element, both length and / or tension compensation and also transverse compensation between the contact element and the phase connection are made possible. In particular, the contact element or the struts are elastically deformable, which simplifies assembly and leads to comparatively safe operation, with electrical contact between the phase connection and the contact element always being present even in the event of vibrations or deformations of the electronics compartment. The contact element is designed, for example, as a PowerBasket from Würth Elektronik.

In an advantageous embodiment, the circuit board has a feed-through opening which is framed on the circumferential side by the contact element and through which a free end of the phase connection is passed at least in sections. The assembly and the installation space required for the electrical contacting he follows on the underside, whereby an optical inspection or control of the contacting from the top facing away from the connector is made possible through the feed-through opening (push-through control). This enables a simple and reliable control or inspection of the plug contact during assembly. In one possible embodiment, the contact element is in electrical contact with the printed circuit board on the upper side. In other words, the contact element is designed as a through-hole connection of the printed circuit board. The contact element thus runs in sections through the circuit board, for example the contact element is seated in a recess or through-opening in the circuit board. This ensures a particularly low overall height of the contact element and the circuit board. Furthermore, a control or inspection of the electrical contact from the top of the circuit board is made possible.

In a conceivable embodiment, the phase connection is formed by an enameled wire. The approximately cylindrical or bolt-shaped phase connection or phase pin has a circular cross-sectional shape, for example with a diameter of 3 mm (millimeters).

In a suitable development, the phase connection is designed in one piece, that is to say in one piece or monolithically, with the electrical coil of the electric motor. In this case, the phase connection is preferably formed by means of one end of the electrical coil. Alternatively, the phase connection is a separate component which is in electrical contact with the electrical coil, in particular directly, and preferably mechanically connected to it, for example soldered or welded on. The phase connection is particularly preferably contacted directly with the electrical coil. When the electrical machine is used as an electrical or electromotive drive of a refrigerant drive, a high current is applied to the stator windings, causing a significant amount of heat to be generated. In order to cool the electric motor during operation, for example, a refrigerant and / or a motor fluid (motor oil) flows around it. This requires a fluid-tight and pressure-tight separation between the electric motor and the electronics compartment, so that the semiconductor switches of the bridge circuit are not damaged or destroyed. An additional or further aspect of the invention therefore provides that the phase connection is guided through a housing wall. In other words, one end of the phase connection is located inside the electronics compartment, and another end of the phase connection is located outside the electronics compartment, these two areas being separated by means of the housing wall. Here, the electrical stator winding is preferably connected to the end of the phase connection located outside the electronics compartment. Due to the passage through the housing wall, the phase connection is kept stable, and electrical contacting with the contact element is simplified.

The phase connection is expediently located in a form-fitting and / or force-fitting manner within a recess in the housing wall. In particular, a pressure-tight and fluid-tight seal is provided between the phase connection and the housing wall. As a result, it is possible to design the electronics compartment pressure-tight and fluid-tight, which is why any damage or contamination of the circuit board is prevented. In particular, the phase connection runs in the axial direction, and the housing wall is arranged essentially perpendicular to the axial direction, that is, parallel to the printed circuit board.

A “form fit” or a “form fit connection” between at least two interconnected parts is understood here and in the following in particular to mean that the interconnected parts are held together at least in one direction by a direct interlocking of contours of the parts themselves or by an indirect one Interlocking takes place via an additional connecting part. The "blocking" of a mutual movement in this direction is therefore due to the shape.

A “force fit” or a “force fit connection” between at least two interconnected parts is understood here and in the following in particular to mean that the interconnected parts are prevented from sliding off one another due to a frictional force acting between them. If there is no “connecting force” causing this frictional force (this means the force that presses the parts against each other, for example a Screw force or the weight itself), the non-positive connection cannot be maintained and thus released.

The advantages and configurations cited with regard to the machine can also be applied to the refrigerant drive and vice versa.

The refrigerant drive according to the invention is part of a motor vehicle and comprises an electrical machine described above as an electrical or electromotive drive for a compressor or compressor head. The Käl temittelantrieb is designed in particular as an electromotive or electric refrigerant compressor (eKMV). The electric machine has, for example, a brushless direct current motor (BLDC) as an electric motor. The refrigerant compressor, in particular the electrical machine, is preferably electrically contacted / contactable with an on-board network of the motor vehicle and / or operated / operated with an electrical voltage of a few volts up to 1000V, in particular with an electrical voltage of 12V, 24V, 48V, 288V, 450V, 650V or 830V.

A refrigerant is compressed by means of the refrigerant compressor during operation. The refrigerant is, for example, a chemical refrigerant such as R134a or R1234yf. Alternatively, the refrigerant is C02. The refrigerant compressor is preferably designed in such a way that the respective refrigerant can be compressed by means of it, with a pressure increase between 5 bar and 20 bar taking place, for example. The refrigerant compressor is, in particular, a component of a refrigeration cycle that is used, for example, to air-condition an interior or to cool an energy store in the motor vehicle, such as a high-voltage battery. For example, the electromotive refrigerant compressor is signal-technically coupled to a BUS system, in particular a LIN or CAN bus.

The electrical machine has a stator with an electrical coil, in particular a number of electrical coils which are combined to form a number of electrical phases of a stator winding's rule. Furthermore, the electrical machine comprises an electronics compartment and a printed circuit board arranged therein. Within the electronics compartment, a phase connection is held in place, which is electrically connected to the stator winding or to the electrical coil, and which is electrically plugged into contact with the circuit board by means of a contact element. In particular, the bridge circuit is used to energize the electrical coil or the electrical phase.

The bridge circuit preferably has a number of bridge branches that corresponds to the number of electrical coils / phases. In particular, the number of bridge branches is equal to the number of electrical phases and / or an integral multiple of the number of electrical coils. For example, an intermediate circuit capacitance is assigned to each bridge branch. Each bridge branch has in particular two series-connected semiconductor switches, in particular power semiconductor switches. The power semiconductor switches are provided and set up to switch an electrical current with an amperage of at least 1A, 2A, 5A or 10A. The power semiconductor switches are preferably IGBTs or field effect transistors (FET), in particular DirectFETs. In particular, two power semiconductor switches are connected in parallel to one another, so that each bridge branch comprises four such power semiconductor switches. In this way, an electrical current carried with the respective power semiconductor switch is reduced, which reduces manufacturing costs.

The refrigerant drive or refrigerant compressor is suitably a constituent part of a refrigerant circuit with a (air conditioning) condenser, as well as with a Ver evaporator, and with the refrigerant compressor. The condenser is fluidly connected between the refrigerant compressor and the evaporator. The refrigerant circuit preferably comprises a further heat exchanger which is connected between the evaporator and the refrigerant compressor and which is preferably in thermal contact with a further component of the motor vehicle, such as a fan line of an air conditioning system or an energy store, such as a high-voltage energy store. The refrigerant circuit is in particular filled with a refrigerant, for example a chemical refrigerant such as R134a, R1234yf, or with CO2. By means of the refrigerant compressor, a pressure of the refrigerant is increased during operation, which is then passed to the condenser, which is preferably in thermal contact with the surroundings of the motor vehicle. The temperature of the refrigerant is preferably adjusted to the ambient temperature or at least the temperature of the refrigerant is lowered by means of the condenser. The refrigerant is expanded with the downstream evaporator, which is why the temperature of the refrigerant is further reduced. In the downstream additional heat exchanger, thermal energy is transferred from the component that is thermally contacted with the additional heat exchanger to the refrigerant, which leads to a cooling of the component and a heating of the refrigerant. The heated refrigerant is preferably fed back to the refrigerant compressor to close the refrigerant circuit.

The statements in connection with the electrical machine and / or the refrigerant drive apply mutatis mutandis to the use and vice versa.

An exemplary embodiment is explained in more detail below with reference to a drawing. Show in it:

Fig. 1 is a perspective view of an electric refrigerant drive with egg ner electrical machine and with a compressor,

FIG. 2 schematically simplifies the refrigerant drive in a sectional view, FIG. 3 shows the refrigerant drive without housing in a side view,

4 shows a through-hole plating of a in a perspective sectional view

Phase connection and a printed circuit board connected to it by means of a contact element,

Fig. 5 is a schematic side view of the contact element and the circuit board in a first embodiment,

Fig. 6 is a schematic side view of the contact element and the circuit board in a second embodiment, and Fig. 7 is a schematic side view of the contact element and the circuit board in a third embodiment. Corresponding parts and sizes are always provided with the same reference numerals in all figures. The refrigerant drive 2 shown in Fig. 1 is preferably installed as a refrigerant compressor in a refrigerant circuit, not shown in detail, of an air conditioner of a motor vehicle. The electromotive refrigerant compressor 2 has an electrical (electromotive) drive in the form of an electrical machine 4 and a compressor (compressor head) 6 coupled to it.

The machine 4, on the one hand, and the compressor 6, on the other hand, are of modular construction so that, for example, a machine 4 can be coupled to different compressors 6. A transition area formed between the modules 4 and 6 has a mechanical interface 8 with a bearing plate 10 on the drive side. In terms of drive technology, the compressor 6 is connected to the machine 4 via the mechanical interface 8, and has a scroll compressor 11 that can be driven by the latter.

For mounting or fastening, the compressor 6 is joined (screwed, connected) to the drive or to the machine 4 by means of flange connections distributed around the circumference and extending in the axial direction A of the refrigerant compressor 1. In the figures, the flange connections 12 are provided with reference numerals merely by way of example. The machine 4, also referred to below as the drive, comprises a pot-like drive or machine housing 14 with two housing sections 14a and 14b, which are separated from one another in a fluid-tight and pressure-tight manner by a monolithically integrated intermediate housing wall 14c (FIG. 2) within the drive housing 14. The drive housing 14 is preferably made as a die-cast part from an aluminum material.

As becomes clear when looking together with FIG. 2, the housing section on the compressor side is intended to be accommodated as a motor housing 14a an electric motor 16 is formed. The motor housing 14a is closed on the one hand by the partition wall or 14c and on the other hand by the end shield 10. The housing sub-area lying opposite the intermediate wall 14c, also referred to below as the housing wall, is designed as an electronics housing 14b in which an electronics compartment 18 for receiving electronics 20 controlling the electric motor 16 is formed.

The drive housing 14a has a refrigerant inlet or refrigerant inlet 22 for connection to the refrigerant circuit, a refrigerant outlet 26 being provided on the bottom of a compressor housing 24. In the connected state, the inlet 22 forms the low-pressure or suction side (suction gas side) and the outlet 26 the high-pressure or pump side (pump side) of the refrigerant drive 2. Fig. 2 shows a schematic and simplified illustration of the electromotive refrigerant drive 2 in a sectional view along an axis of rotation 28 of the electric motor 16, which here is a brushless direct current motor (BLDC) and has a cylindrical rotor 30. This is surrounded on the circumference by means of a hollow cylindrical stator 32. The rotor 30 comprises a number of permanent magnets and is mounted rotatably about the axis of rotation 28 by means of a shaft 34 between a bearing 36 (FIG. 3) and the end shield 10. The stator 32 has a number of electrical coils which are energized by the electronics 20, which in turn is connected to a bus system and the vehicle electrical system of the motor vehicle, for example.

“Axial” or the axial direction A is understood here and below in particular to mean a direction parallel (coaxial) to the axis of rotation 28 of the electric motor 16, that is to say perpendicular to the end faces of the stator 32. Correspondingly, here and in the following, “radial” or a radial direction R is understood to mean in particular a direction oriented perpendicularly (transversely) to the axis of rotation 28 of the electric motor 16 along a radius of the stator 32 or the electric motor 16. Here and in the following, “tangential” or a “tangential direction” is in particular a direction along the circumference of the stator 32 or the Electric motor 16 (circumferential direction, azimuthal direction), that is, a direction perpendicular to the axial direction A and to the radial direction R, understood.

The electronics 20 are arranged in the electronics compartment 18 of the electronics housing 14b, which is separated from the stator 32 and the rotor 30 by means of the housing wall 14c. A housing cover 38, which is releasably attached to the electronics housing 14b by means of screws, closes an access opening of the electronics housing 14b. The electronics 20 is mounted in the electronics compartment 18 when the housing cover 38 is open and is still easily accessible for maintenance or repair purposes when the housing cover 38 is removed.

The electronics 20 have a printed circuit board or PCB 40 arranged parallel to the housing wall 14c. A bridge circuit 42 of the circuit board 40 is connected to a polyphase stator winding 50 of the stator 32 formed from coils 48 via phase connections 44 which are axially guided through the housing wall 14c by means of vias 46 (Fig. 3, Fig. 4) and are held in place . The coil windings of the individual coils 48 are connected to the stator or motor phases in a star or delta connection in a connection ring 52 placed on the end face of the stator 32, and by means of the vias 46 and phase connections 44 that protrude axially therefrom to the bridge circuit 42. The bridge circuit 42 is fed from the vehicle electrical system by means of two connections 54.

As can be seen in the illustration in FIG. 3, the stator 32 has a six-phase stator winding 50, and thus accordingly six through-contacts 46 and six phase connections 44. The phase connections 44, also referred to as phase pins, have a cylindrical or bolt-shaped or pin-shaped geometry. The phase connections 44 are preferably designed with a circular cross-sectional shape and, for example, have a diameter of 3 mm (millimeters).

The phase connections 44 are, for example, made in one piece, that is to say in one piece or monolithically, with the stator winding 50. Here are the phase connections 44 essentially designed as coil ends of the coils 48. Alternatively, the phase connections 44 are each designed as a separate component, which is electrically contacted within the connection ring 52 with the respective electrical coil 48, in particular directly, and preferably mechanically connected to this, for example soldered or welded.

The phase connections 44 are in this case electrically connected to the bridge circuit 42 by means of an associated contact element 56 on an underside 58 of the circuit board 40. The underside 58 is understood here to mean, in particular, the surface of the printed circuit board 40 facing the stator 32 or the housing wall 14c, regardless of the actual orientation in space. Correspondingly, the surface of the printed circuit board 40 opposite the underside 58, on which in particular the bridge circuit 42 is arranged and which faces away from the stator 32 or the housing wall 14c, is also referred to below as the upper side 60.

4 shows an exemplary embodiment of a refrigerant drive 2 as a 470V refrigerant compressor. As can be seen comparatively clearly in the illustration in FIG. 4, the approximately cage-shaped contact element 56 is provided for electrical plug-in contact with the phase connection 44, and is suitable and set up for this.

The contact element 56 shown individually in FIG. 5 has an approximately ring-shaped contact area 62 for electrical contacting and mechanical fastening on the circuit board 40. On the contact area or contact ring 62 in this embodiment, for example, four vertically axially upwardly rising struts 64 as flexurally elastic tabs, which are directed obliquely or inclined to the contact ring 62 to an unspecified center axis of the contact element 56. The struts 64 are provided with reference numerals in the figures merely by way of example. The contact element 56 is thus designed as a plug socket for the phase connection 44. The space enclosed by the struts 64 is narrowed radially in a contact plane K spaced axially from the contact ring 62 to a diameter which is smaller than the diameter of the phase connection 44. The free ends of the struts 64 are widened radially outward from the contact plane K, so that a simplified introduction or a simplified insertion of the phase connection 44 is made possible.

In the plug-connected state, the struts 64 therefore rest against the outer circumference of the phase connection 44 with a certain mechanical preload or spring tension, so that reliable electrical contacting is ensured even in the event of shocks or vibrations occurring during operation.

According to the invention, the contact plane K is axially spaced from a printed circuit board plane (not shown in more detail), in particular to the underside 58, of the Lei terplatte 40. As can be seen comparatively clearly with reference to FIG. 4, the phase connection 44 for plug-in contacting is inserted essentially perpendicularly or axially into the contact element 56 from the underside 58 or the housing wall 14c.

The contact element 56 is designed in particular as an SMD socket, this means that the contact ring 62 is designed as a solderable connection surface, which is soldered directly to conductor tracks 68 of the printed circuit board 40 by means of a soldered connection 66.

In the exemplary embodiment in FIGS. 4 and 5, the contact element 56 is fastened to the upper side 60 of the circuit board 40. The circuit board 40 here has a bore or lead-through opening (PCB breakthrough) 70 through which the Stre ben 64 to the underside 58 are guided. The contact ring 62 surrounds the feed-through opening 70 on the circumferential side. In other words, the contact ring 62 is arranged on an edge of the feed-through opening 70. This arrangement of the contact element 56 is also referred to below as push-fit assembly. On the one hand, the push-through installation has a particularly low overall height of the contact element 56 and the circuit board 44. On the other hand, due to the feed-through opening 70 and the central recess of the contact ring 62, a particularly optical control or inspection of the electrical contacting from the top side 60 of the circuit board 40, that is to say when the housing cover 38 is open, is made possible.

With the aid of FIGS. 6 and 7, two alternative designs for the arrangement and contacting or assembly of the contact element 56 are described below.

The embodiment of FIG. 6 shows a structural assembly of the Kontaktele element 56 on the underside 58 of the circuit board 40. In this embodiment, the contact ring 62 is arranged on the underside edge of the feed-through opening 70. In the case of a structural assembly of this type, the equipping and the space consumption take place on the same side of the printed circuit board, with the through-opening 70 still making it possible to monitor the electrical contacts through insertion.

In the variant of FIG. 7, there is a structural assembly of the contact element 56 on the underside 58 of the circuit board 40 without a feed-through opening 70. This embodiment enables, in particular opposite to the contact element 56, an additional installation space on the top side 60 of the printed circuit board 40.

The invention is not restricted to the exemplary embodiments described above. Rather, other variants of the invention can be derived from the specialist man without leaving the subject matter of the invention sen. In particular, all the individual features described in connection with the exemplary embodiments can also be combined with one another in other ways without departing from the subject matter of the invention.

It is essential that the joining or plug-in contacting of the phase connection 44 and the contact element 56 takes place from the underside 58 or the housing wall 14c. List of reference symbols

2 refrigerant drive / refrigerant compressor 4 machine / drive 6 compressor

8 interface

10 bearing shield

11 scroll compressors

12 Flange connection 14 Drive housing

14a housing section / motor housing 14b housing section / electronics housing 14c housing partition / housing wall 16 electric motor 18 electronics compartment

20 electronics

22 inlet

24 compressor housing 26 outlet 28 axis of rotation

30 rotor

32 stator

34 wave

36 bearings 38 housing cover

40 circuit board

42 Bridge circuit 44 Phase connection 46 Through-hole plating 48 Coil

50 stator winding

52 Connection ring 54 Connection 56 contact element 58 bottom 60 top

62 Contact area / contact ring 64 Strut

66 Solder connection 68 Conductor track 70 Feed-through opening A, axial direction

R radial direction

K contact level

Claims

Expectations

1. Electrical machine (4) of a motor vehicle, comprising an electric motor (16) and an electronics compartment (18) with a printed circuit board (40) arranged therein and with a phase connection (44) which is held stationary within the electronics compartment (18) and which has a stator winding (50) of a stator (32) of the electric motor (16) is electrically contacted,

- A bridge circuit (42) being carried on an upper side (60) of the printed circuit board (40),

- The circuit board (40) having a contact element (56) for electrical plug-in contacting of the phase connection (44), and

- The plug contact on one of the top (60) opposite bottom (58) of the circuit board (40) takes place.

2. Electrical machine (4) according to claim 1, characterized in that the electrical contact is made perpendicular to the underside (58).

3. Electrical machine (4) according to claim 1 or 2, characterized in that the electrical contact between the contact element (56) and the phase connection (44) takes place in a contact plane (K) which is spaced parallel to a printed circuit board plane of the printed circuit board (40 ) is.

4. Electrical machine (4) according to one of claims 1 to 3, characterized in that the contact element (56) is designed as a socket, in particular as an SMD socket.

5. Electrical machine (4) according to one of claims 1 to 4, characterized in that the circuit board (40) has a feed-through opening (70) which is framed on the circumference by the contact element (56) and through which a free end of the phase connection ( 44) is passed through at least in sections.

6. Electrical machine (4) according to one of claims 1 to 5, characterized in that the contact element (56) is electrically contacted on the top (60) with the circuit board (40).

7. Electrical machine (4) according to one of claims 1 to 6, characterized in that the phase connection (44) is formed by an enameled wire.

8. Electrical machine (4) according to one of claims 1 to 7, characterized in that the phase connection (44) is formed by a coil end of a coil (48) of the stator winding (50).

9. Electrical machine (4) according to one of claims 1 to 8, characterized in that the phase connection (44) is guided through a housing wall (14c).

10. Electric refrigerant drive (2) of a motor vehicle, in particular Käl temittelverdichter for a vehicle air conditioning system, comprising a compressor (6) which is drive-coupled to an electrical machine (4) according to one of claims 1 to 9.