Electric drive with torque vectoring function in modular design

Abstract

According to the invention, an electromechanical axle drive train (1) with - an electric traction machine (2), - an intermediate shaft (3), - a differential gear (4), - a torque vectoring module (5) with an electric motor (6) and a coupling gear (7), wherein the differential gear (4) and the torque vectoring module (5) are arranged on the intermediate shaft (3) which is axially parallel to the traction machine (2).

Description

[0001] DE 10 2022 101 130 A1 discloses an electric axle drive for a vehicle, comprising an electric motor for providing drive power with a stator and a rotor rotatable relative thereto about a rotational axis, a power distribution gearbox having a gearbox input for introducing drive power of the rotor and, on the output side, a first gearbox output and a second gearbox output acting in parallel thereto for delivering the drive power, a torque vectoring unit having, for the controlled introduction of a differential torque between the first and second gearbox outputs superimposed on the torque associated with the drive power, a first coupling output coupled to the first gearbox output and a second coupling output acting in parallel thereto and coupled to the second gearbox output,wherein a transmission device connected on the input side to the first and second transmission outputs is arranged with a first output side and a second output acting parallel thereto, and the first and / or second output is rotatable about a further axis of rotation offset axially parallel to the axis of rotation.

[0002] The object of the invention is to improve the electromechanical axle drive train.

[0003] This object is achieved according to the invention with the features of claim 1.

[0004] Thus, the problem is solved according to the invention with a drive structure consisting of an electric traction motor, an intermediate shaft, a differential gear, and a torque vectoring module, which in turn has an electric motor and a coupling gear. The differential gear and the torque vectoring module are arranged on the intermediate shaft, which is axially parallel to the traction motor and spaced apart from the intermediate shaft. The two output shafts leading to the wheels are also arranged axially parallel to the intermediate shaft, with the outputs of the differential gear each connected to an output shaft via a spur gear. Thus, the electric traction motor is also arranged axially parallel to the intermediate shaft and spaced apart from the output shafts.

[0005] In contrast to the drive concepts of the state of the art, an integration of the torque vectoring module (TV module for short) on the intermediate shaft of the drive is now provided, which, due to its modularity, can be installed in the drive structure or not, without adapting the drive structure to the installation of the TV module.

[0006] A torque vectoring function creates a speed and torque difference in the drivetrain between the left and right wheels of an axle. Unlike a differential gear, which results in a speed and torque change due to different friction conditions between the left and right wheels, torque vectoring actively applies a speed and torque difference to one wheel compared to the other wheel on the axle using an additional electric motor. This difference is therefore not caused by the different friction between one wheel and the other wheel on the same axle.

[0007] While this increases torque compared to placement on the input shaft, it also offers the option of arranging the TV module parallel to the traction motor. With this arrangement, the two spur gear stages on the output can be placed directly next to each other between the steering gears. This allows the axle drive to be designed significantly narrower (in the axial direction of the axle) in the area of ​​the output shafts.

[0008] By placing the TV module on the intermediate shaft, the installation space can be minimized to a minimum. While this reduces the power of the traction drive, the reduction ratio in the coupling gear allows for very high differential torques to be generated between the output shafts.

[0009] In particular, the provided plug-in connections between the TV module and the differential gear allow for flexible configuration with or without the TV module. The drive structure can thus function with or without a TV module.

[0010] In an advantageous embodiment of the invention, two spur gear stages arranged axially next to one another as spur gears complete the power path as output to the wheels.

[0011] In another embodiment, the electric motor is arranged radially within the coupling gear. This enables a particularly compact arrangement.

[0012] Another embodiment provides for both output shafts of the differential gear to continue the power path on the same axial side of the differential gear. This leaves space on the opposite axial side for the TV module.

[0013] The traction machine is particularly preferably a radial flux machine, since it requires less radial installation space than an axial flux machine.

[0014] In another design, the coupling gear and the differential gear are designed as planetary gears, with the planets of both gears being identical. This allows for standardization of components and reduction of costs.

[0015] Advantageously, the coupling gear and the differential gear are designed as planetary gears, and the planets of both gears have straight teeth. This allows for easy assembly of these two gears from the axial direction and / or makes it easier to assemble each individual gear from its components.

[0016] In a further embodiment of the invention, the inverter for controlling the electric motor is integrated into the inverter for controlling the traction machine. This allows the traction machine inverter to be pre-equipped with the control board for the TV module's electric motor, which provides the freedom to equip the drive structure with the TV module or not.

[0017] The design of the spur gear stages is provided with opposing helix angles in the toothing so that the axial forces from the toothing support each other.

[0018] Further details of the invention are shown in the figure for Fig. 1 described and visible.

[0019] The Fig.1 shows a drive structure of the electromechanical axle drive train 1 consisting of an electric traction machine 2, an intermediate shaft 3, a differential gear 4, and a torque vectoring module 5, which in turn has an electric motor 6 and a coupling gear 7. The differential gear 4 and the torque vectoring module 5 are arranged on the intermediate shaft 3, which is axially parallel to the traction machine 2 and spaced apart from the intermediate shaft 3. The two output shafts 15, 16 leading to the wheels 11 and 12 are also arranged axially parallel to the intermediate shaft 3, with the outputs of the differential gear 4 each connected to an output shaft 15 or 16 via a spur gear 9 or 10, respectively. The electric traction machine 2 is thus also arranged axially parallel to the intermediate shaft 3 and spaced apart from the output shafts 15, 16.The two output shafts 15, 16 are clearly aligned with each other, since a wheel 11 or 12 is arranged at their respective ends. List of reference symbols 1 electromechanical axle drive train 2 electric traction machines 3 Intermediate shaft 4 differential gears 5 Torque vectoring module 6 Electric motor 7 coupling gear 8 spur gears 9 First spur gear stage 10 Second spur gear stage 11 First Wheel 12 Second wheel 13 First output shaft (differential gear) 14 Second output shaft (differential gear) 15 First output shaft 16 Second output shaft QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2022 101 130 A1

[0001]

Claims

[1] Electromechanical axle drive train (1) with - an electric traction machine (2), - an intermediate shaft (3), - of a differential gear (4), - a torque vectoring module (5) with an electric motor (6) and a coupling gearbox (7), characterized by , that the differential gear (4) and the torque vectoring module (5) are arranged on the intermediate shaft (3) which is spaced parallel to the axis of the traction machine (2). [2] Electromechanical axle drive train (1) according to claim 1, characterized by , that two axially adjacent spur gear stages (9, 10) as a spur gear transmission (8) complete the power path as output to the wheels (11, 12). [3] Electromechanical axle drive train (1) according to one of the preceding claims, characterized by , that the electric motor (6) is arranged radially inside the coupling gear (7). [4] Electromechanical axle drive train (1) according to one of the preceding claims, characterized by , that both output shafts (13, 14) of the differential gear (4) continue the power path on the same axial side of the differential gear (4). [5] Electromechanical axle drive train (1) according to one of the preceding claims, characterized by , that the traction machine (2) is a radial flux machine. [6] Electromechanical axle drive train (1) according to one of the preceding claims, characterized by , that the coupling gear (7) and the differential gear (4) are designed as planetary gears and the planets of both gears (4, 7) are identical. [7] Electromechanical axle drive train (1) according to one of the preceding claims, characterized by , that the coupling gear (7) and the differential gear (4) are designed as planetary gears and the planets of both gears (4, 7) have straight teeth. [8] Electromechanical axle drive train (1) according to one of the preceding claims, characterized by , that the inverter for controlling the electric motor (6) is integrated into the inverter for controlling the traction machine (2).

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