BEARING ASSEMBLY FOR INTEGRATING INTO AN ELECTRIC DRIVE ASSEMBLY FOR A VEHICLE, AND ELECTRIC DRIVE ASSEMBLY COMPRISING THE BEARING ASSEMBLY

Abstract

A bearing assembly of an electric drive assembly for a vehicle includes an insulating device having a sleeve with an electrically insulating coating, and a bearing device disposed in the sleeve. In an example embodiment, the sleeve has an inner peripheral surface and an outer peripheral surface, and the outer peripheral surface is formed by the electrically insulating coating. In an example embodiment, the sleeve is formed from steel, and the electrically insulating coating is formed from a plastic material having an electrically insulating property. In an example embodiment, the sleeve is designed as a cylinder having an end face with an outer side, and the electrically insulating coating is disposed on the outer side. In an example embodiment, the bearing device is a floating bearing axially movable relative to the sleeve.

Claims

1. A bearing assembly to be integrated into an electric drive assembly for a vehicle, having a bearing device and an insulating device for electrically insulating the bearing device, the insulating device being designed as a sleeve, the bearing device being received in the sleeve, wherein the sleeve has an electrically insulating coating.

2. The bearing assembly according to claim 1, wherein the sleeve has an inner peripheral surface and an outer peripheral surface, wherein the outer peripheral surface has or is formed by the electrically insulating coating.

3. The bearing assembly according to claim 1, wherein the sleeve is formed from steel or in that the electrically insulating coating is formed from a plastic material having an electrically insulating property.

4. The bearing assembly according to claim 1, wherein the sleeve is designed as a cylinder, wherein the cylinder has an end face, wherein the electrically insulating coating is arranged on an outer side of the end face.

5. The bearing assembly according to claim 1, wherein the bearing device is a floating bearing, wherein the bearing device is axially movable relative to the sleeve.

6. The bearing assembly according to claim 4, wherein the end face forms an end stop for the bearing device, wherein a spring device is arranged between the end stop and the bearing device for the elastic or resilient arrangement of the bearing device relative to the end stop.

7. An electric drive assembly for a vehicle, having an electric drive section, the electric drive section having an electric drive with a rotor and the electric drive section having a shaft, the shaft being connected to the rotor and the shaft having a shaft section, having a transmission section, a transmission device being arranged in the transmission section, the shaft being connected to the transmission device in gearing terms, having a housing section, the shaft section being rotatably mounted relative to the housing section, wherein the electric drive assembly comprises a bearing assembly according to claim 1.

8. The electric drive assembly according to claim 7, wherein the shaft section is rotatably mounted relative to the housing section in the bearing device of the bearing assembly.

9. The electric drive assembly according to claim 7, wherein the housing section has a receiving region for the bearing assembly, wherein the receiving region comprises and/or is formed by a bushing.

10. The electric drive assembly according to claim 9, wherein the sleeve is received in the receiving region and/or in the bushing in a non-rotatable manner.

11. A bearing assembly of an electric drive assembly for a vehicle, comprising: an insulating device comprising a sleeve with an electrically insulating coating; and a bearing device disposed in the sleeve.

12. The bearing assembly of claim 11, wherein: the sleeve comprises an inner peripheral surface and an outer peripheral surface; and the outer peripheral surface is formed by the electrically insulating coating.

13. The bearing assembly of claim 11, wherein: the sleeve is formed from steel; and the electrically insulating coating is formed from a plastic material having an electrically insulating property.

14. The bearing assembly of claim 11, wherein: the sleeve is designed as a cylinder having an end face with an outer side; and the electrically insulating coating is disposed on the outer side.

15. The bearing assembly of claim 11, wherein the bearing device is a floating bearing axially movable relative to the sleeve.

16. The bearing assembly of claim 14 further comprising a spring device, wherein: the bearing device is a floating bearing axially movable relative to the sleeve, the end face forms an end stop for the bearing device; and the spring device is arranged between the end stop and the bearing device.

17. An electric drive assembly for a vehicle, comprising: the bearing assembly of claim 11; a housing section; a transmission section comprising a transmission device; and an electric drive section comprising: an electric drive comprising a rotor; and a shaft connected to the rotor and to the transmission device, the shaft comprising a shaft section rotatably mounted relative to the housing section.

18. The electric drive assembly of claim 17, wherein the shaft section is rotatably mounted relative to the housing section in the bearing device.

19. The electric drive assembly of claim 17, wherein: the housing section comprises a receiving region comprising a bushing; and the bearing assembly is disposed in the bushing.

20. The electric drive assembly of claim 19, wherein the sleeve is rotatably fixed in the bushing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] An example embodiment is described in more detail below with reference to the attached drawings. In the figures:

[0032] FIG. 1 shows a schematic representation of an electric drive assembly as an exemplary embodiment of the invention; and

[0033] FIG. 2 shows a schematic axial longitudinal section through a bearing assembly of the electric drive assembly.

DETAILED DESCRIPTION

[0034] Corresponding or identical components are each provided with the same reference symbols in the figures.

[0035] FIG. 1 shows a schematic representation of an electric drive assembly 1 for a vehicle, not shown, as an exemplary embodiment of the disclosure. For example, the vehicle can be designed as a single or multi-track vehicle and/or as a single or multi-axle vehicle. For example, the vehicle is a purely electric vehicle or a hybrid vehicle. The vehicle can be designed, for example, as a passenger car, bus, or truck. Alternatively, however, the vehicle can also be designed, for example, as a bicycle (pedelec), a motorcycle with electric drive, or an e-scooter.

[0036] The electric drive assembly 1 is used to generate and/or provide a traction torque, e.g., a main traction torque, for the vehicle. For this purpose, the electric drive assembly 1 has an electric drive section 2, which has an electric drive 3 for generating the traction torque and a rotor shaft 4 for transmitting the traction torque. The electric drive 3 can be electrically connected to a power device, such as a battery or accumulator, to provide power to generate traction torque. The electric drive 3 can, for example, be designed as a DC motor, synchronous motor or asynchronous motor.

[0037] The electric drive 3 has a stator 5 and a rotor 6. The rotor 6 is connected to the rotor shaft 4 in a non-rotatable manner. The rotor shaft 4 defines a main axis H with its axis of rotation, wherein with respect to the main axis H, the stator 5 and the rotor 6 are arranged to be coaxial and/or concentric with respect to one another. For example, the electric drive 3 is designed as an internal rotor.

[0038] Furthermore, the electric drive assembly 1 has a transmission section 7, which is used to transmit and/or translate and/or distribute the traction torque of the electric drive 3. For this purpose, a transmission device 8, indicated only schematically, is arranged in the transmission section 7, wherein the transmission device 8 can include a clutch device, e.g., a form-fitting or friction-locking clutch, and/or a shift device, e.g., an electrically and/or hydraulically actuated shift cylinder, and/or a transmission device, e.g., a planetary and/or stepped gear transmission. The electric drive section 2 and the transmission section 7 are connected to one another in gearing terms via the rotor shaft 4, wherein the rotor shaft 4 forms an input shaft into the transmission device 8. The traction torque can be transmitted to one or more wheels of the vehicle via an output shaft 9, for example.

[0039] Furthermore, the electric drive assembly 1 has a separating section 10 which separates a motor compartment of the electric drive section 2 from an adjacent transmission compartment of the transmission section 7. For this purpose, the separating section 10 is arranged in the axial direction with respect to the main axis H between the electric drive section 2 and the transmission section 7. For example, the motor compartment can be a dry region and the adjacent transmission compartment can be another dry region or an oil region, wherein the separating section 10 forms a dirt-tight and optionally an oil-tight separation between the electric drive section 2 and the transmission section 7. The motor compartment can alternatively be designed as a wet compartment, e.g., as a common compartment with the transmission compartment. In particular, the electric drive 3 can be designed as a wet-running electric drive.

[0040] The electric drive 3 or electric drive assembly 1 has a housing 11, wherein the stator 5 and the rotor 6 are arranged in the housing 11. Optionally, the transmission device 8 or the transmission section 7 is also arranged in the housing 11. The housing 11 is closed off on a side facing away from the transmission by a housing section 12, so that the housing section 12 delimits a housing interior of the housing 11.

[0041] For the rotatable mounting of the rotor shaft 4, the electric drive assembly 1 has a bearing device 13 and a further bearing device 14, wherein the rotor shaft 4 is supported in the radial direction via the bearing devices 13, 14. In the exemplary embodiment shown, the bearing devices 13, 14 are each designed as a ball bearing, in particular as a deep groove ball bearing. Each of the bearing devices 13, 14 has a rotating inner ring 18 and a stationary outer ring 19.

[0042] The rotor shaft 4 has a rotor shaft section 15 facing away from the transmission section 7. The rotor shaft section 15 forms an end section of the rotor shaft 4 on the drive side. The bearing device 13 is arranged in the housing section 12. The housing section 12 is closed via the bearing devices 13.

[0043] The housing section 12 has a receiving section 16 shown in FIG. 2, which is designed to receive the bearing device 13. A bushing 27 made of steel or plastic is arranged in the receiving section 16. Alternatively, the receiving section 16 is formed by the bushing 27. The bushing 27 is designed as a cylinder bushing which is closed in regions on the end face. The bushing 27 is fixedly connected to the housing section 12. It can be fastened to the housing section 12 in a materially bonding, force-fitting and/or form-fitting manner.

[0044] The bearing device 13 is designed as a floating bearing, which is axially movable in the receiving section 16, in particular in the bushing 27, relative to the main axis H and relative to the housing section 12. The axial movement of the bearing device 13 can compensate for a possible thermal linear expansion of the shaft 4. The further bearing device 14 is received in a further receiving section 17 in the housing 11. It is received in the further receiving section 17 in a non-movable manner.

[0045] In a motor operation of the electric drive 3, discharge currents and/or potential differences can be caused, which can discharge via the bearing devices 13, 14 and damage the bearing devices 13, 14. Therefore, the bearing devices 13, 14 are insulated against electrical currents in the housing 11, in the housing section 12 and/or in the shaft 4. The insulation of the bearing devices 13, 14 allows for the electrical currents to be interrupted. By preventing the flow of current through the bearing devices 13, 14, they can be protected from increased wear and failures can be avoided. Thus, expenses for repairing the electric drive assembly 1 and in particular for replacing the bearing devices 13, 14 can be saved.

[0046] An insulating device 21 is provided to insulate the bearing device 13, which is designed as a floating bearing. Together with the bearing device 13, it forms a component of a bearing assembly 20 of the electric drive assembly 1.

[0047] The bearing assembly 20 is shown in FIG. 2 in an axial sectional view. The bearing assembly 20 is received in the receiving section 16 of the housing section 12, in particular in the bushing 27.

[0048] The insulating device 21 is designed as a cylindrical sleeve 22 with a cylinder jacket. The cylinder jacket has an inner peripheral surface 23, an outer peripheral surface 24 and an annular end face 25 that is open centrally in the axial direction. The sleeve 22 is designed as a steel sleeve. It has an electrically insulating coating 26 formed from a plastic material having an electrically insulating property. The coating 26 is applied, e.g., sprayed, on the outer peripheral surface 24 of the sleeve and on an outer side of the end face 25 and covers them completely. In particular, the electrically insulating coating 26 forms the outer peripheral surface 24 of the cylinder jacket and the outer side of the end face 25.

[0049] The sleeve 22 is arranged in the bushing 27 in a force-fitting and/or friction-locking manner and thus in a non-rotatable manner. In this arrangement, the electrically insulating coating 26 abuts an inner peripheral surface of the bushing 27 and an inner surface of an end face of the bushing 27.

[0050] As a floating bearing, the bearing device 13 is received in the sleeve 22 in an axially movable manner. The outer ring 19 of the bearing device 13, which is formed from steel, can move along the inner peripheral surface 23 of the sleeve 22, which is formed from steel, which results in only slight wear during axial movement. The electrically insulating coating 26 is arranged facing away from the outer ring 19 and is therefore not affected by the axial movement. As a result, a wear of the electrically insulating coating 26 can be avoided and the bearing device 13 can be safely electrically insulated.

[0051] The end face 25 of the sleeve 22 forms an end stop for the bearing device 13 when it performs the axial movement. A spring device 28 is arranged between the end face 25 and the outer ring 19 of the bearing device 13 to form an elastic and/or resilient stop.

REFERENCE NUMERALS

[0052] 1 Electric drive assembly

[0053] 2 Electric drive section

[0054] 3 Electric drive

[0055] 4 Rotor shaft

[0056] 5 Stator

[0057] 6 Rotor

[0058] 7 Transmission section

[0059] 8 Transmission device

[0060] 9 Output shaft

[0061] 10 Separating section

[0062] 11 Housing

[0063] 12 Housing section

[0064] 13 Bearing device

[0065] 14 Further bearing device

[0066] 15 Rotor shaft section

[0067] 16 Receiving section

[0068] 17 Further receiving section

[0069] 18 Rotating inner ring

[0070] 19 Stationary outer ring

[0071] 20 Bearing assembly

[0072] 21 Insulating device

[0073] 22 Sleeve

[0074] 23 Inner peripheral surface

[0075] 24 Outer peripheral surface

[0076] 25 End face

[0077] 26 Electrically insulating coating

[0078] 27 Bushing

[0079] 28 Spring device

[0080] H Main axis