Electrical drive unit and also drive arrangement for an electrical drive unit

Abstract

An electrical drive unit for an electrically at least partially driveable motor vehicle and also to a drive arrangement for an electrically at least partially driveable motor vehicle, comprising an electrical drive unit according to the disclosure. An electrical drive unit for an electrically at least partially driveable motor vehicle comprises an electrical drive machine and also an output device for transmitting a torque, which is provided by the electrical drive machine, to driven vehicle wheels of a motor vehicle, and also comprising a torque converter, which is arranged in the torque transmission path between a rotor of the electrical drive machine and the output device, for the purpose of matching the torque which is provided by the electrical drive machine to a respective torque requirement.

Claims

1. An electrical drive unit for an electrical motor vehicle, comprising: an electrical drive machine; an output device for transmitting a torque provided by the electrical drive machine, to drive vehicle wheels of the electrical motor vehicle; a torque converter, arranged in a torque transmission path between a rotor of the electrical drive machine and the output device, wherein the torque converter is configured to match the torque provided by the electrical drive machine to a respective torque requirement; a first cooling circuit which is designed to dissipate heat from the electrical drive machine; and a second cooling circuit which is designed to dissipate heat from the torque converter.

2. The electrical drive unit of claim 1, wherein a clutch for disconnecting and opening the torque transmission path between the electrical drive machine and the output device is arranged parallel to the torque converter.

3. The electrical drive unit of claim 2, wherein a step-up transmission for stepping up the torque which is provided by the clutch is arranged in the torque transmission path between the clutch and the output device.

4. The electrical drive unit of claim 1, wherein the torque converter further includes a guide wheel and a freewheel.

5. The electrical drive unit of claim 1, wherein the electrical drive unit furthermore comprises an electrically driveable pump which is flow-connected to a flow chamber of the torque converter, wherein the flow chamber is configured to maintain a minimum pressure of a fluid in the flow chamber of the torque converter or for assisting in implementing a minimum pressure of a fluid in the flow chamber of the torque converter.

6. The electrical drive unit of claim 1, wherein the electrical drive unit furthermore comprises a mechanically driveable pump which is mechanically coupled to a pump impeller or to a turbine wheel of the torque converter and is flow-connected to a flow chamber of the torque converter, wherein the flow chamber is configured to maintain a minimum pressure of a fluid in the flow chamber of the torque converter or for assisting in implementing a minimum pressure of a fluid in the flow chamber of the torque converter.

7. The electrical drive unit of claim 3, wherein the electrical drive unit furthermore comprises a lubrication system by way of which lubricant can be supplied to the step-up transmission, wherein a pump configured to generate a lubricant volumetric flow is a constituent part of the lubrication system.

8. The electrical drive unit of claim 7, wherein the electrical drive unit includes an axle which is mechanically coupled to the output device.

9. An electrical drive unit, comprising: an electrical drive machine; an output device for transmitting a torque provided by the electrical drive machine to drive vehicle wheels of a motor vehicle; a torque converter arranged in a torque transmission path between a rotor of the electrical drive machine and the output device, wherein the torque converter is configured to match the torque provided by the electrical drive machine to a respective torque requirement; a step-up transmission for stepping up the torque which is provided by the torque converter being arranged between the torque converter and the output device; a first cooling circuit which is designed to dissipate heat from the electrical drive machine; and a second cooling circuit which is designed to dissipate heat from the torque converter.

10. The electrical drive unit of claim 9, wherein the electrical drive unit includes a clutch configured to disconnect and open the torque transmission path between the electrical drive machine and the output device.

11. The electrical drive unit of claim 10, wherein the clutch is arranged parallel to the torque converter.

12. The electrical drive unit of claim 9, wherein the torque converter is configured to operate in a slip mode configured to allow rotation speed of a pump side to be higher than the rotation speed of a turbine side.

13. The electrical drive unit of claim 9, wherein the electrical drive unit includes a mechanically drivable pump mechanically coupled to a pump impeller or to the turbine wheel of the torque converter.

14. The electrical drive unit of claim 13, wherein the mechanically drivable pump is configured to be flow-connected to a flow chamber of the torque converter and configured to provide a minimum pressure of a fluid in the flow chamber of the torque converter.

15. The electrical drive unit of claim 9, wherein the electrical drive unit includes a differential transmission mechanically coupled to the output device of the electrical drive unit at one end and is mechanically coupled to an axle at the other end, wherein the differential transmission is configured to transmit torque from the electrical drive unit to the axle.

16. An electrical drive unit, comprising: an electrical drive machine; an output shaft for transmitting a torque configured to drive vehicle wheels of a motor vehicle, the output shaft including a rotation axis corresponding to a torque transmission path of the electrical drive unit; and a torque converter arranged in the torque transmission path between a rotor of the electrical drive machine and the output shaft, wherein the torque converter is configured to match the torque provided by the electrical drive machine to a respective torque requirement; a first cooling circuit which is designed to dissipate heat from the electrical drive machine; and a second cooling circuit which is designed to dissipate heat from the torque converter.

17. The electrical drive unit of claim 9, further comprising an electrically driveable pump flow-connected to a flow chamber of the torque converter, wherein the flow chamber is configured to maintain a minimum pressure of a fluid in the flow chamber of the torque converter or for assisting in implementing a minimum pressure of a fluid in the flow chamber of the torque converter.

18. The electrical drive unit of claim 1, wherein the torque converter is configured to operate in a slip mode configured to allow rotation speed of a pump side to be higher than the rotation speed of a turbine side.

19. The electrical drive unit of claim 16, wherein the torque converter is configured to operate in a slip mode configured to allow rotation speed of a pump side to be higher than the rotation speed of a turbine side.

20. The electrical drive unit of claim 16, further comprising an axle mechanically coupled to the output shaft.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The disclosure described above will be explained in more detail below in relation to the relevant technical background with reference to the associated drawing which shows a preferred refinement. The disclosure is in no way restricted by the purely schematic drawing, and it should be noted that the exemplary embodiment shown in the drawing is not restricted to the dimensions illustrated. In the drawing

(2) FIG. 1: shows a schematic illustration of a drive arrangement according to the disclosure comprising a drive unit according to the disclosure.

DETAILED DESCRIPTION

(3) The drive arrangement 2 comprises an electrical drive unit 1, a differential transmission 32 which is mechanically coupled to the electrical drive unit 1, and also an axle 33 which is coupled to the differential transmission 32 and on which vehicle wheels 34 are arranged in a rotationally fixed manner.

(4) The electrical drive unit 1 comprises an electrical drive machine 10, which is substantially an electric motor, a torque converter 20 and also an output device 31 which implements the mechanical coupling between the electrical drive unit 1 and the differential transmission 32, so that torque which is provided by the electrical drive machine 10 can be transmitted to the vehicle wheels 34.

(5) In this case, a first torque transmission path between the electrical drive unit 10 and the output device 31 is implemented via the torque converter 20.

(6) A clutch 25 is arranged parallel to the torque converter 20. A second torque transmission path between the electrical drive machine 10 and the output device 31 can be implemented via this clutch 25, where the clutch 25 is designed to open or to disconnect the second torque transmission path.

(7) The electrical drive machine 10 has a rotor 11 and also a stator 12, wherein the rotor 11 is arranged such that it can rotate relative to the stator 12 and is mechanically coupled to an input side 28 of the torque converter 20 and, respectively, to an input side 29 of the clutch 25 for transmitting torque.

(8) A step-up transmission 30 is arranged downstream of the torque converter 20 and, respectively, downstream of the clutch 25 in the torque transmission path between the electrical drive machine 10 and the output device 31, for stepping up torque which is provided by the torque converter 20 and/or by the clutch 25.

(9) The torque converter 20 comprises a pump impeller 21, a trubine wheel 22, a guide wheel 23 and also a freewheel 24. In respect of its design and its functioning, the torque converter 20 therefore corresponds substantially to a so-called TRILOK converter.

(10) The guide wheel 23 is mounted on the freewheel 24, so that the torque converter 20 automatically switches over to purely hydrodynamic coupling. Said torque converter is configured in such a way that the guide wheel 23 jointly rotates freely after the switchover, so that a torque can no longer be supported and the input and output torque are the same.

(11) The pump impeller 21 is mechanically coupled to the rotor 11 of the electrical machine 10, and the turbine wheel 22 is mechanically coupled to the step-up transmission 30.

(12) The torque converter 20 can be operated in a so-called slip mode, where the rotation speed of the pump impeller 21 can be increased on account of torque differences which occur between the two wheels 21, 22. Accordingly, a correspondingly increased torque can be provided at the turbine wheel 22. Therefore, it is possible to respond to a torque requirement at the output device 31 and, respectively, the vehicle wheels 34 in a simple manner by adjusting the torque converter 20 and, respectively, to also provide an increased torque due to relatively high rotation speeds of the electrical drive machine 10.

(13) Here, the clutch 25 is configured in a normally closed clutch form 26. An alternative which is embodied by a normally open clutch form 27 of the clutch 25 is illustrated using dashed lines. An embodiment of the clutch 25 as a so-called normally stay clutch, which can likewise be used as an alternative to the normally closed clutch form 26, is not illustrated.

(14) Furthermore, FIG. 1 shows a pump 40, 41. Said pump is embodied either as an electrically driveable pump 40 which can be driven by an electric pump motor 43; or as a mechanically driveable pump 41 which can be driven by torque which is provided by the electrical drive machine 10. The pump 40, 41 is designed to ensure the supply of the torque converter 20 with fluid, in particular with oil, and therefore to ensure a minimum pressure of a fluid in the flow chamber of the torque converter 20 or to assist in realizing a minimum pressure of this kind. At the same time or as an alternative, cooling of the torque converter 20 is realized by the pump 40, 41.

(15) In addition, the pump 40, 41 can be used for operating the clutch 25.

(16) In this case, the pump 40, 41 is part of a lubrication system 42 by way of which lubricant can be supplied to the step-up transmission 30.

(17) During operation of a motor vehicle which comprises the drive arrangement 2 according to the disclosure, torque which is provided by the electrical drive machine 10 can be transmitted to the step-up transmission 30 via the torque converter 20 or the clutch 25 and then to the differential transmission 32 by the output device 31 and can be transmitted from there to the axle 33 and finally to vehicle wheels 34.

(18) Since the torque which is provided by the electrical drive machine 10 can be transmitted firstly via the torque converter 20 and, if required, directly via the clutch 25, a further torque range can be covered by the electrical drive unit 1 according to the disclosure than is provided by the electrical drive machine 10 alone owing to the torque variation by the torque converter 20.

(19) The refinement according to the disclosure of the electrical drive unit and a drive arrangement proposed here renders it possible to combine a wide range of applications of the electrical drive machine with optimum driving operation of a motor vehicle which is equipped with said electrical drive machine with a low investment requirement.

LIST OF REFERENCE SYMBOLS

(20) 1 Electrical drive unit 2 Drive arrangement 10 Electrical drive machine 11 Rotor 12 Stator 20 Torque converter 21 Pump impeller 22 Turbine wheel 23 Guide wheel 24 Freewheel 25 Clutch 26 Normally closed clutch form 27 Normally open clutch form 28 Input side of the torque converter 29 Input side of the clutch 30 Step-up transmission 31 Output device 32 Differential transmission 33 Axle 34 Vehicle wheel 40 Electrically driveable pump 41 Mechanically driveable pump 42 Lubrication system 43 Electric pump motor