Including electric motors with cooling and / or lubrication systems featuring wet spaces, and motor vehicles equipped with electric motors.

Abstract

The present invention relates to an electric motor including a cooling and / or lubrication system with a wet space, and a motor vehicle having an electric motor. For the electric motor, particularly for driving a motor vehicle (1), it includes a cooling and / or lubrication system (12) having a wet space (13) for containing a cooling and / or lubricating medium (14), wherein the stator (5) and / or rotor (6) of the electric motor (2) are at least partially arranged in and / or define the wet space (13), wherein the electric motor (2) includes at least one stator-side transmission member (15) and at least one rotor-side transmission member (17), the stator-side transmission member and the rotor-side transmission member forming an electrically sliding contact, wherein at least one of the transmission members (15, 17) is at least partially arranged in and / or defines the wet space (13).

Description

Technical Field

[0001] This invention relates to an electric motor, particularly for driving motor vehicles, the motor including a cooling and / or lubrication system having a wet space for containing cooling and / or lubricating media, wherein the stator and / or rotor of the motor are at least partially arranged in and / or define the wet space, and wherein the motor includes at least one stator-side transmission component and at least one rotor-side transmission component configured to make electrical sliding contact. The invention also relates to a motor vehicle. Background Technology

[0002] Electric motors known from the prior art for propulsing motor vehicles, for example, include a stator and a rotor. During the operation of such motors, heat is typically generated, both due to friction arising from rotation and due to the current present in the motor or electric motor. This necessitates not only lubrication of components rotating relative to each other (e.g., the stator or rotor), but also cooling of other heated components of the motor associated with the present current (e.g., the excitation coils). For this purpose, a wet space is typically provided, in which the components to be lubricated or cooled come into contact with a cooling and / or lubricating medium—particularly oil.

[0003] Another aspect of the corresponding motor involves the need to transmit current between rotating and stationary components, particularly between stator-side and rotor-side components, such as between the excitation coil and control electronics or excitation module. This transmission is typically achieved through electroslidable contact, for example, using slip rings and brushes. Components associated with the sliding contact are usually arranged in a dry space isolated from the external environment. This prevents the slip rings and brushes from contacting external contaminants, meaning any signs of wear are kept as low as possible.

[0004] For example, such a motor with an oil-cooled and oil-lubricated stator and rotor is known from document US 4,241,271 A. In this system, slip rings and brushes are provided for current transmission, and the slip rings and brushes are arranged in a dry space and form an electrosliding contact.

[0005] Instead of arranging the components forming the electrical sliding contact in a dry space, it is known in the prior art to integrate these components into a cooling system specifically designed for this purpose, in which a coolant circulates. One such system is known from document US 3316 519 A, in which water, for example, is used as the coolant, and it relates to a gas turbine capable of operating at high speeds.

[0006] A common problem in systems known from the prior art is that the isolation of the space where components forming electrical sliding contacts are arranged can only be achieved through high levels of technical cost. In particular, the problem lies in the requirement for reliable isolation between rotating and non-rotating surfaces, which is typically achieved using radial shaft seal rings. The associated required components increase space requirements, causing the motor's axial dimension to increase by several centimeters, for example, by approximately 25 millimeters. Furthermore, these additional components increase the motor's overall weight by several kilograms, for example, by approximately 4 kilograms. Summary of the Invention

[0007] The object of this invention is to provide an improved motor compared to others.

[0008] For motors of the type described at the beginning, this objective is achieved by having at least one of the transmission components arranged at least partially in and / or defining the wet space.

[0009] This invention is based on the view that not only the components forming the electric sliding contact / sliding contact, but also the stator and / or rotor are arranged in or define a common wet space in such a way that cooling and / or lubricating media are used in a coordinated manner to cool or lubricate the stator and / or rotor, as well as the sliding contact. In other words, a common wet space is formed by merging a wet space in which at least part of the stator and / or rotor and / or the wet space defined by the stator and / or rotor are arranged, and a wet space in which at least one of the transmission components is arranged and / or the wet space defined by at least one of the transmission components is merged. In the prior art, in addition to a wet space where at least a stator and / or rotor are arranged and / or defined by the stator and / or rotor, a dry space is also provided where at least one of the transmission components is arranged and / or defined by at least one of the transmission components. Compared with the prior art motors, the motor according to the present invention completely eliminates the necessity of the dry space because the stator and / or rotor and at least one of the transmission components are arranged at least partially in a common wet space, or the common wet space is defined by at least one of the stator and / or rotor and the transmission component. Because of the common wet space, there is no need for isolation elements to seal the separate space defined by at least one of the transmission components and / or at least one of the transmission components.

[0010] A wet space can be understood as a continuous and fluid-tightly designed spatial section or region within an electric motor, in which cooling and / or lubricating media are contained or can be contained. A wet space may therefore include a space section in which at least partially a stator and / or rotor are arranged and / or defined by the stator and / or rotor, and a space section in which at least partially at least one of the transmission components is arranged and / or defined by at least one of the transmission components, wherein these space sections are either connected to each other or configured as a common space section. The motor may have a housing that at least segmentally defines the wet space, which is configured as a cavity.

[0011] An electric motor can be an electric motor / electric motor used to drive or propel a motor vehicle. The rotor can be securely connected to the motor's shaft, so that the rotor and shaft rotate together about an axis of rotation, with the stator extending radially around the rotor. In this case, the motor forms what is called an inner mover. Alternatively, the rotor can also extend radially about a stator centrally located relative to the axis of rotation, thus forming an outer mover. Electric motors typically operate using energy stored in the motor vehicle's electrical energy storage system.

[0012] Regarding the sliding contact portion, there are also stator-side transmission components and rotor-side transmission components. The transmission components are in contact with each other, so that when the rotor rotates, the transmission components or corresponding sections of the transmission components slide relative to each other, thereby maintaining the contact between these components even during motor operation, by means of which electrical contact is formed. The electric sliding contact portion is specifically used for energizing the rotor-side excitation coil or tapping the current induced in the excitation coil. In addition to the excitation coil used as an electromagnet, the motor may also have at least one permanent magnet.

[0013] Regarding the structural design of the motor, it can be specified that a rotor position detector is provided on the end side of the housing, and the rotor or shaft is held in position by means of the rotor position detector. The rotor position detector (in which the rotating component is supported, for example, by means of a ball bearing) can be held in position by a bearing end cover of the housing. Preferably, the motor is sealed at the end side by a housing cover in a fluid-tight manner.

[0014] The stator and / or rotor, as well as the transmission components, can be arranged in a wet space such that the entire surface of these components is in contact with a cooling and / or lubricating medium. Alternatively, these components can be arranged at least partially or in sections in the wet space. That is, these components partially protrude into the wet space, so that at least a portion of their surfaces are in contact with the cooling and / or lubricating medium. Furthermore, these components can at least partially define the wet space. That is, at least a portion of the surface of these components externally defines the wet space or forms a corresponding wall of the wet space. In summary, the walls defining the wet space can be formed by the stator and / or rotor and / or stator-side transmission components and / or rotor-side transmission components and / or the inner wall of the housing and / or other components of the motor.

[0015] In the motor according to the invention, it is preferably specified that the transmission component on the stator side is a brush, and the transmission component on the rotor side is a slip ring. This type of sliding contact has proven to be very advantageous and reliable in the field of motors. Therefore, the brush can be fixedly fastened to the stator relative to the motor position and can have conductive brush bristles or brush wires fastened to the brush holder. Similarly, the conductive slip ring is concentrically arranged around the axis of rotation and fastened to the rotor or shaft, wherein the brush bristles or brush wires press against the slip ring due to their bending elasticity, thereby forming a contact and thus constructing an electrical contact.

[0016] Particularly preferably, the slip ring is made of alloy steel, and the brush is made of a non-ferrous metal-free material (i.e., a metal or alloy, particularly a silver alloy). The term "non-ferrous metal-free" means that the corresponding material does not contain any non-ferrous metals, such as copper. The corresponding material pairing has good tolerance / compatibility / adaptability with preferred cooling and / or lubricating media (e.g., oil), thereby ensuring the longest possible service life for the slip ring and brush.

[0017] A cooling and / or lubrication system can be integrated into or incorporated into the cooling and / or lubrication circuit of a motor vehicle, in which the cooling and / or lubricating medium circulates. The cooling and / or lubricating medium can be an oil with particularly positive properties in terms of cooling or lubrication. The oil can be introduced, particularly sprayed, into the wet space using an oil gun. The oil gun can extend along the axis of rotation through a recess in the stator or rotor or the shaft connected thereto. In the outlet region of the oil gun, a nozzle can be provided that protrudes into the area of ​​the wet space, particularly where a transmission component is arranged, thereby ensuring continuous and reliable cooling or lubrication of the transmission component. To introduce the cooling and / or lubricating medium into the wet space, the opening or nozzle of the oil gun can be arranged in a recess extending longitudinally along the stator or rotor or the shaft connected thereto, wherein the cooling and / or lubricating medium enters the wet space, for example, through radial recesses or holes in the component. In particular, the cooling and / or lubricating medium is uniformly distributed in the wet space by the rotation of the rotating component.

[0018] The cooling and / or lubrication circuit of a motor vehicle may include an oil reservoir from which oil can be introduced into a wet space via a supply line. Oil can also be introduced from the supply line to an oil nozzle. To close the cooling and / or lubrication circuit, oil can be returned from the wet space to the oil reservoir via a corresponding return line. An oil pump for the cooling and / or lubrication circuit may be appropriately located in the area of ​​the supply and / or return lines.

[0019] The electric motor may include a transmission that is connected to or can be connected to components of the drivetrain of a motor vehicle, wherein at least one component of the transmission is at least partially arranged in or defines a wet space. The wet space, in addition to having sections in which at least a stator and / or rotor are arranged and / or defined by the stator and / or rotor, and sections in which at least one transmission component is arranged and / or defined by the transmission component, also includes sections in which at least one component of the transmission is arranged and / or defined by the at least one component of the transmission, wherein these sections are either connected to each other or configured to form a common section. In this embodiment, the cooling and / or lubrication system is used not only to cool or lubricate the stator / rotor and transmission components of the electric motor, but also to cool or lubricate the components of the transmission, particularly at least one gear of the transmission.

[0020] The drivetrain is used to transmit the torque generated by the electric motor to the wheels of a motor vehicle. The drivetrain also includes other components, such as a differential, universal joint, etc. A transmission, preferably at least partially disposed within the motor housing, can be connected to or be able to connect to the rotor or shaft on the drive side, and to or be able to connect to the shaft of the motor vehicle's drivetrain on the output side, wherein the speed change between these components is accomplished by means of the transmission. The transmission can be, for example, a coaxial transmission, particularly a planetary gear transmission. In this case, the shaft on the output side of the drivetrain and the shaft or rotor on the drive side are located on the same axis of rotation relative to the transmission.

[0021] The motor is preferably a separately excited synchronous motor, wherein an excitation module is provided for supplying power to at least one rotor-side excitation coil, and the electrical connection between the excitation module and at least one rotor-side excitation coil is formed or can be formed by an electrically sliding contact. The separately excited synchronous motor enables stepless speed regulation, wherein, for this purpose, the excitation module is configured with or electrically connected to a corresponding power electronic device.

[0022] The excitation module can be connected to the stator-side transmission components, particularly the brushes, via suitable electrical connection devices, such as excitation current cables. The rotor-side transmission components—especially slip rings—can also be connected to the rotor-side excitation coils via suitable electrical connection devices, such as cables. Ultimately, the rotor-side excitation coils can be driven by the excitation module or power electronics equipment via sliding contacts and electrical connection devices.

[0023] The object of the present invention is also achieved by a motor vehicle having the motor described above. All the advantages and features of the motor according to the present invention can be applied to the motor vehicle according to the present invention, and vice versa. Attached Figure Description

[0024] Other advantages and details of the invention will become apparent from the embodiments described below and from the accompanying drawings.

[0025] in:

[0026] Figure 1 A motor vehicle according to the invention, having an electric motor according to the invention, is schematically shown;

[0027] Figure 2 It schematically shows the relationship with Figure 1 Details related to the motors of motor vehicles; and

[0028] Figure 3 schematically shown Figure 2 An enlarged view of the sliding contact portion of the motor shown. Detailed Implementation

[0029] Figure 1 A motor vehicle 1 according to the invention is shown, including a motor 2 according to the invention. The motor 2 is currently configured as an electric motor, which can propel the motor vehicle 1 using energy stored in an energy storage device 3 of the motor vehicle 1. For this purpose, the motor 2 is connected to the transmission system 4 of the motor vehicle 1, which... Figure 1 The image is only schematically shown and no further details, such as the corresponding differential, universal joint, etc., are shown.

[0030] Details related to motor 2 are in Figure 2 As shown in the diagram, the motor 2 includes a stator 5 and a rotor 6. The rotor 6 is rotatably supported about a rotation axis 7 and is therefore configured, for example, as an inner rotor. The rotor 6 is connected to a shaft 33. The motor 2 is externally enclosed by a housing 8, which has bearing covers 9 at its ends. A rotor position detector 10 is provided in the area of ​​the bearing cover 9, by means of which the position of the rotor 6 or shaft 33 is detected, for example, by means of ball bearings or the like. The housing 8 is closed at its ends by housing covers 11.

[0031] The motor 2 includes a cooling and / or lubrication system 12, by means of which the stator 5 and rotor 6 are cooled and lubricated. The cooling and / or lubrication system 12 includes a wet space 13. The stator 5 and rotor 6 are arranged in a first spatial section 13a of the wet space 13, which may also be defined by the stator 5 and / or rotor 6. A cooling and / or lubricating medium 14 can be introduced into the wet space 13, or has already been introduced into the wet space 13, where the cooling and / or lubricating medium is currently oil, to cool or lubricate these components. Here, the cooling of the stator 5 and rotor 6 is primarily achieved by means of the cooling and / or lubricating medium 14 present in the gap between the stator 5 and rotor 6 and in the gap between the stator 6 and the inner wall of the housing 8.

[0032] The motor 2 also includes a stator-side transmission component 15 (i.e., brush 16) and a rotor-side transmission component 17 (i.e., slip ring 18). The transmission components 15 and 17 form an electrically sliding contact portion, which... Figure 3 The image is enlarged in size. Specifically, the rotor-side transmission component 17 is connected to the rotor-side excitation coil 30 via an electrical contact device (not shown in detail). The stator-side transmission component 15 is connected to the excitation module 20 or power electronics device 21 via an excitation current cable 19. Specifically, the motor 2 is configured as a separately excited synchronous motor, wherein stepless speed regulation can be achieved by means of the rotor-side excitation coil 30 and the stator-side excitation coil 31. Alternatively, permanent magnets may be provided instead of the stator-side excitation coils.

[0033] The transmission components 15 and 17 are also arranged in the wet space 13, specifically in the second spatial section 13b of the wet space 13. It may also be specified that at least one of the transmission components 15 and 17 defines the second section 13b. Here, the first section 13a and the second section 13b of the wet space 13 are connected to each other in such a way that the cooling and / or lubricating medium 14 is used not only to cool or lubricate the stator 5 and rotor 6, but also to cool or lubricate the brush 16 and slip ring 18. Here, due to the rotation of the respective components (e.g., rotor 6, shaft 33, and slip ring 18), the cooling and / or lubricating medium 14 is uniformly distributed in the wet space 13.

[0034] To ensure the best possible material resistance between the cooling and / or lubricating medium 14 and the transmission components 15, 17, for example, it is specified that the slip ring 18 is made of alloy steel, while the brush 16 is made of a non-ferrous metal material. The non-ferrous metal material is either a metal or an alloy, currently a silver alloy. This material selection prevents corrosion of the brush 16 or the slip ring 18, which would occur if the brush 16 were made of a non-ferrous metal or the slip ring 18 were made of a bronze alloy.

[0035] The motor 2 also includes a transmission 22, currently a coaxial transmission, which is connected to a shaft (not shown in detail) of the transmission system 4. The axis of rotation of the transmission 22 coincides with the axis of rotation 7 of the rotor 6. Components 23 of the transmission 22, i.e., gears, are also arranged in the wet space 13, specifically in the third spatial section 13c of the wet space 13, which connects to sections 13a and 13b. It can also be specified that components 23 of the transmission 22 define the third section 13c. Therefore, the cooling and / or lubricating medium 14 is also used for cooling and lubricating the transmission 22.

[0036] according to Figure 1The cooling and lubrication system 12 of the motor 2 is integrated into the cooling and / or lubrication circuit 24 of the motor vehicle, in which the cooling and / or lubrication medium 14 circulates. The cooling and / or lubrication medium 14 is introduced from the reservoir 27 into the wet space 13 via a supply line 26 by means of a pump 25. For this purpose, the supply line 26 is connected to an oil gun 28 of the cooling and lubrication system 12, so that the cooling and / or lubrication medium 14 is sprayed into the space section 13b of the wet space 13 via the oil gun 28. Here, the oil gun 28 extends from the outside into the housing 8 and passes through the central hole of the rotor 6 along the axis of rotation 7, wherein the oil gun 28 has a nozzle 34 at its end side for introduction into the second section 13b. The cooling and / or lubrication medium 14 is introduced into the second section 13b here, for example, via a radial notch or hole 35 in the shaft 33. Due to the rotation of the rotating components (particularly the rotor 6 and the rotor-side transmission component 17 or slip ring 18), the cooling and / or lubricating medium 14 is distributed as evenly as possible within the wet space 13. The return of the cooling and / or lubricating medium 14 from the wet space 13 to the oil reservoir 27 is carried out via a corresponding return line 29 and, if necessary, an oil pump located in the area of ​​the return line.

Claims

1. An electric motor comprising a cooling and / or lubrication system (12), the cooling and / or lubrication system having a wet space (13) for containing a cooling and / or lubricating medium (14), wherein, The stator (5) and / or rotor (6) of the motor (2) are at least partially arranged in and / or define the wet space (13), wherein the motor (2) includes at least one stator-side transmission component (15) and at least one rotor-side transmission component (17), the stator-side transmission component and the rotor-side transmission component forming an electrically sliding contact. Wherein, at least one of the transmission components (15, 17) is arranged at least partially in the wet space (13) and / or defines the wet space. Its features are, The motor (2) includes a transmission (22) which is connected to or can be connected to a component of the drivetrain of a motor vehicle, wherein at least one component of the transmission (22) is at least partially arranged in or defines the wet space (13).

2. The motor according to claim 1, Its features are, The stator-side transmission component (15) is a brush (16), and the rotor-side transmission component (17) is a slip ring (18).

3. The motor according to claim 2, Its features are, The slip ring (18) is made of alloy steel, and the brush (16) is made of a non-ferrous metal and conductive material, i.e., made of metal or alloy.

4. The motor according to claim 3, Its features are, The alloy is a silver alloy.

5. The motor according to any one of the preceding claims, Its features are, The cooling and / or lubrication system (12) is incorporated into or can be incorporated into the cooling and / or lubrication circuit (24) of the motor vehicle (1), in which the cooling and / or lubrication medium (14) circulates.

6. The motor according to claim 5, Its features are, The cooling and / or lubricating medium (14) is oil.

7. The motor according to any one of the preceding claims, Its features are, The transmission (22) is a coaxial transmission.

8. The motor according to any one of the preceding claims, Its features are, The motor is a separately excited synchronous motor, wherein an excitation module (20) is provided for supplying power to at least one rotor-side excitation coil (30), wherein the electrical connection between the excitation module (20) and at least one rotor-side excitation coil (20) is constructed by means of an electric sliding contact or can be constructed by means of an electric sliding contact.

9. The motor according to any one of the preceding claims, Its features are, The motor is used to drive a motor vehicle (1).

10. A motor vehicle having an electric motor (2) according to any one of the preceding claims.

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