ELECTRICAL MACHINE COMPRISING A COOLING AND OR LUBRICATING SYSTEM HAVING A WET CHAMBER, MOTOR VEHICLE HAVING AN ELECTRICAL MACHINE

Abstract

An electrical machine, in particular for driving a motor vehicle, including a cooling and/or lubricating system having a wet chamber for accommodating a cooling and/or lubricating medium. A stator and/or a rotor of the electrical machine is at least partially arranged in the wet chamber and/or delimits it, and the electrical machine includes at least one stator-side transmission component and at least one rotor-side transmission component, which form an electrical sliding contact. At least one of the transmission components is at least partially arranged in the wet chamber and/or delimits

Claims

1. An electrical machine, in particular for driving a motor vehicle, comprising: a cooling and/or lubricating system having a wet chamber for accommodating a cooling and/or lubricating medium, wherein a stator and/or a rotor of the electrical machine is at least partially arranged in the wet chamber and/or delimits it, wherein the electrical machine comprises at least one stator-side transmission component and at least one rotor-side transmission component, which form an electrical sliding contact, wherein at least one of the transmission components is at least partially arranged in the wet chamber and/or delimits it.

2. An electrical machine as claimed in claim 1, wherein the stator-side transmission component is a brush and the rotor-side transmission component is a slip ring.

3. An electrical machine as claimed in claim 2, wherein the slip ring consists of a steel alloy and the brush consists of an electrically conductive material free of nonferrous metals, namely a metal or an alloy, in particular a silver alloy.

4. An electrical machine as claimed in claim 1, wherein the cooling and/or lubricating system can be incorporated or is incorporated in a cooling and/or lubricating circuit of the motor vehicle, in which the cooling and/or lubricating medium, in particular an oil, circulates.

5. An electrical machine as claimed in claim 1, wherein the electrical machine comprises a transmission, in particular a coaxial transmission, which is connectable or connected to a component of a drivetrain of the motor vehicle, wherein at least one component of the transmission is at least partially arranged in the wet chamber or delimits it.

6. An electrical machine as claimed in claim 1, wherein it is an externally excited synchronous machine, wherein an exciter module is provided for energizing at least one rotor-side field coil, wherein an electrical connection between the exciter module and the at least one rotor-side field coil is formed or can be formed by means of the electrical sliding contact.

7. A motor vehicle having an electrical machine as claimed in claim 1.

8. An electrical machine as claimed in claim 2, wherein the cooling and/or lubricating system can be incorporated or is incorporated in a cooling and/or lubricating circuit of the motor vehicle, in which the cooling and/or lubricating medium, in particular an oil, circulates.

9. An electrical machine as claimed in claim 3, wherein the cooling and/or lubricating system can be incorporated or is incorporated in a cooling and/or lubricating circuit of the motor vehicle, in which the cooling and/or lubricating medium, in particular an oil, circulates.

10. An electrical machine as claimed in claim 2, wherein the electrical machine comprises a transmission, in particular a coaxial transmission, which is connectable or connected to a component of a drivetrain of the motor vehicle, wherein at least one component of the transmission is at least partially arranged in the wet chamber or delimits it.

11. An electrical machine as claimed in claim 3, wherein the electrical machine comprises a transmission, in particular a coaxial transmission, which is connectable or connected to a component of a drivetrain of the motor vehicle, wherein at least one component of the transmission is at least partially arranged in the wet chamber or delimits it.

12. An electrical machine as claimed in claim 4, wherein the electrical machine comprises a transmission, in particular a coaxial transmission, which is connectable or connected to a component of a drivetrain of the motor vehicle, wherein at least one component of the transmission is at least partially arranged in the wet chamber or delimits it.

13. An electrical machine as claimed in claim 2, wherein it is an externally excited synchronous machine, wherein an exciter module is provided for energizing at least one rotor-side field coil, wherein an electrical connection between the exciter module and the at least one rotor-side field coil is formed or can be formed by means of the electrical sliding contact.

14. An electrical machine as claimed in claim 3, wherein it is an externally excited synchronous machine, wherein an exciter module is provided for energizing at least one rotor-side field coil, wherein an electrical connection between the exciter module and the at least one rotor-side field coil is formed or can be formed by means of the electrical sliding contact.

15. An electrical machine as claimed in claim 4, wherein it is an externally excited synchronous machine, wherein an exciter module is provided for energizing at least one rotor-side field coil, wherein an electrical connection between the exciter module and the at least one rotor-side field coil is formed or can be formed by means of the electrical sliding contact.

16. An electrical machine as claimed in claim 5, wherein it is an externally excited synchronous machine, wherein an exciter module is provided for energizing at least one rotor-side field coil, wherein an electrical connection between the exciter module and the at least one rotor-side field coil is formed or can be formed by means of the electrical sliding contact.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0023] Further advantages and details of the present invention result from the exemplary embodiments described hereinafter and on the basis of the figures. In the schematic figures:

[0024] FIG. 1 shows a motor vehicle according to the invention having an electrical machine according to the invention,

[0025] FIG. 2 shows details with respect to the electrical machine of the motor vehicle from FIG. 1, and

[0026] FIG. 3 shows an enlarged view of a sliding contact of the electrical machine shown in FIG. 2.

DETAILED DESCRIPTION

[0027] FIG. 1 shows a motor vehicle 1 according to the invention comprising an electrical machine 2 according to the invention. The electrical machine 2 is designed in the present case as an electric motor which is usable by means of energy stored in electrical energy storage device 3 of the motor vehicle 1 for the propulsion of the motor vehicle 1. The electrical machine 2 is connected for this purpose to a drivetrain 4 of the motor vehicle 1, which is only schematically indicated in FIG. 1, without further details such as corresponding differentials, universal shafts, and the like.

[0028] Details with respect to the electrical machine 2 are shown in FIG. 2. The electrical machine 2 comprises a stator 5 and a rotor 6. The rotor 6 is rotatably mounted around a rotational axis 7 and thus forms an internal rotor motor by way of example. The rotor 6 is connected here to a shaft 33. The electrical machine 2 is terminated to the outside by means of a housing 8, which has a bearing plate 9 on the end face. A rotor position encoder 10 is provided in the region of the bearing plate 9, by means of which the rotor 6 or the shaft 33, respectively, is rotatably held in position, for example by a ball bearing or the like. The housing 8 is closed on the end face by a housing cover 11.

[0029] The electrical machine 2 comprises a cooling and/or lubricating system 12, by means of which the stator 5 and the rotor 6 can be cooled and lubricated. The cooling and/or lubricating system 12 comprises a wet chamber 13. The stator 5 and the rotor 6 are arranged in a first spatial section 13a of the wet chamber 13, wherein it can similarly be provided that the stator 5 and/or the rotor 6 delimits the first section 13a. A cooling and/or lubricating medium 14, in the present case an oil, for cooling or lubricating these components, respectively, is introducible or introduced into the wet chamber 13. The cooling of the stator 5 and the rotor 6 primarily takes place here by means of the cooling and/or lubricating medium 14 present in a gap between the stator 5 and the rotor 6 and in a gap between the stator 6 and the inner wall of the housing 8.

[0030] The electrical machine 2 furthermore comprises a stator-side transmission component 15, namely a brush 16, and a rotor-side transmission component 17, namely a slip ring 18. The transmission components 15, 17 form an electrical sliding contact, which is shown enlarged in FIG. 3. Specifically, the rotor-side transmission component 17 is connected via electrical contacting means (not shown in greater detail), to rotor-side field coils 30. The stator-side transmission component 15 is in turn connected via an exciter current cable 19 to an exciter module 20 or a power electronics unit 21, respectively. The electrical machine 2 is specifically designed as an externally excited synchronous machine, in which a continuous speed regulation is possible by means of the rotor-side field coils 30 and stator-side field coils 31. Alternatively, permanent magnets can similarly be provided instead of the stator-side field coils.

[0031] The transmission components 15, 17 are also arranged in the wet chamber 13, namely in a second spatial section 13b of the wet chamber 13. It can similarly be provided that at least one of the transmission components 15, 17 delimits the second section 13b. The first section 13a and the second section 13b of the wet chamber 13 are connected to one another here in such a way that the cooling and/or lubricating medium 14 is used both for cooling or lubricating, respectively, the stator 5 and the rotor 6 and also the brush 16 and the slip ring 18. The cooling and/or lubricating medium 14 is distributed uniformly in the wet chamber 13 here due to the rotation of the corresponding components, such as the rotor 6, the shaft 33, and the slip ring 18.

[0032] To ensure the best possible material compatibility between the cooling and/or lubricating medium 14 and the transmission components 15, 17, it is provided by way of example that the slip ring 18 consists of a steel alloy and the brush 16 consists of a material free of nonferrous metals. The material free of nonferrous metals is a metal or an alloy, respectively, in the present case a silver alloy. This material selection avoids corrosion occurring on the brush 16 or the slip ring 18, respectively, which would occur if the brush 16 would have nonferrous metals or the slip ring 18 were to consist of a bronze alloy.

[0033] The electrical machine 2 furthermore comprises a transmission 22, in the present case a coaxial transmission, which is connected to a shaft (not shown in greater detail) of the drivetrain 4. The rotational axis of the transmission 22 coincides here with the rotational axis 7 of the rotor 6. A component 23 of the transmission 22, namely a gearwheel, is also arranged in the wet chamber 13, namely in a third spatial section 13c of the wet chamber 13, which is connected to the sections 13a, 13b. It can similarly be provided that a component 23 of the transmission 22 delimits the third section 13c. The cooling and/or lubricating medium 14 is therefore also used for cooling and lubricating the transmission 22.

[0034] The cooling and lubricating system 12 of the electrical machine 2 is incorporated according to FIG. 1 in a cooling and/or lubricating circuit 24 of the motor vehicle, in which the cooling and/or lubricating medium 14 circulates. The cooling and/or lubricating medium 14 is introduced here by means of a pump 25 via a supply line 26 from an oil reservoir 27 into the wet chamber 13. For this purpose, the supply line 26 is connected to an oil lance 28 of the cooling and lubricating system 12, so that cooling and/or lubricating medium 14 is sprayed via the oil lance 28 into the spatial section 13b of the wet chamber 13. The oil lance 28 extends for this purpose from the outside into the housing 8 and along the rotational axis 7 through a central drilled hole of the rotor 6, wherein the oil lance 28 has a nozzle 34 on the end face for the introduction into the second section 13b.

[0035] The cooling and/or lubricating medium 14 is introduced here, for example, via radial recesses or drilled hole 35 of the shaft 33 into the second section 13b. The most uniform possible distribution of the cooling and/or lubricating medium 14 inside the wet chamber 13 takes place due to the rotation of rotating components, in particular the rotor 6 and the rotor-side transmission component 17 or the slip ring 18, respectively. The return of the cooling and/or lubricating medium 14 from the wet chamber 13 to the oil reservoir 27 takes place via a corresponding return line 29 and possibly a further oil pump provided in the region of the return line.