Compact power assembly with electric motor

Abstract

The invention relates to a compact powertrain with an electric motor comprising: an inverter unit having an inverter and an inverter housing; an electric motor comprising a rotor and a stator and a motor housing, the rotor defining a motor axis, the electric motor providing a torque; a reduction gear unit comprising a reduction gear and a reduction gear cover, the reduction gear defining an output reduction gear axis, the output reduction gear axis being parallel to the motor axis, the reduction gear cover and the inverter housing being arranged at opposite ends of the electric motor, the inverter housing having a recess, the recess region being completely placed in the inverter housing convexity, the output reduction gear axis passing through the recess region, not through the inverter housing inner cavity. An inductive charging module is rigidly attached to at least one of: a) the inverter housing motor housing, c) the reduction gear cover, the inductive charging module being designed to use electrical components of the inverter, and / or the inductive charging module being cooled by a liquid cooling circuit cooling the inverter and / or the electric motor and / or the reduction gear transmission unit.

Description

Technical Field

[0001] This invention relates to a powertrain for use in electric vehicles, wherein an electric vehicle refers to a vehicle that is at least partially propelled by electricity from a battery installed in the vehicle. The invention also relates to electric vehicles equipped with such a powertrain. Background Technology

[0002] It is generally advantageous to provide compact components for the powertrain. For example, compact packaging saves space, thus improving the packaging of different vehicle components. Compact components also reduce losses, such as power losses in the connection mechanism between the inverter and the motor. Compact components also facilitate high motor speeds. Electric vehicles may also include an inductive charging module, which can be paired with an external module outside the electric vehicle for, for example, charging a battery inside the electric vehicle. In prior art electric vehicles, the inductive charging module is generally arranged separately from the motor.

[0003] Compact assembly of powertrains has been disclosed, for example, in DE19714784A1. DE19714784A1 discloses a compact arrangement of powertrain components in which the electric motor is located between the geared unit and the inverter. This arrangement disclosed in DE19714784A1 allows only one output terminal to which external mechanical loads can be applied.

[0004] WO2017054687A1 discloses a powertrain arrangement in which an electric motor, a gear drive unit, and an inverter are sequentially arranged along a common axis. Because of this arrangement of the powertrain components as disclosed in WO2017054687A1, the entire powertrain extends primarily in one direction, i.e., along the common axis. This results in a large, unfavorable extension dimension along this axis. This arrangement also results in a relatively long conductor length in the electrical connection mechanism between the inverter and the motor, causing increased power losses. Summary of the Invention

[0005] Therefore, the object of the present invention is to provide an improved powertrain arrangement that allows for more versatile options for integrating powertrain arrangements in a vehicle, which, for example, also ensures improved component encapsulation in the vehicle, resulting in a reduced extension dimension (installation length) along the main axis of the component.

[0006] One aspect of the invention is to provide a compact powertrain arrangement in which the entire powertrain is tightly fitted into a cuboid, and external mechanical loads can be applied to its two output ends. For this purpose, a differential is employed, which allows for different speeds at the two output ends, with the reduction gear and differential located at the motor end opposite the inverter. The output reduction gear axis passing through the differential passes through the inverter housing at the other end of the motor. This design allows for a powertrain arrangement whose spatial dimensions are approximately symmetrical about a center point, where the entire powertrain can be tightly fitted into a cuboid; particularly here, the provided compact powertrain has similar extension dimensions in three spatial directions along a Cartesian coordinate system. The compact powertrain arrangement is achieved by using a notch in the inverter housing through which the output shaft passes. The notch in the inverter housing allows for a reduction in the overall installation length of the powertrain (without increasing the extension dimension of the powertrain components on one side). This arrangement also allows for small conductor lengths in the electrical connection mechanism between the inverter and the motor, resulting in minimal power loss.

[0007] Furthermore, the arrangement of the powertrain of the present invention also allows external non-mechanical interfaces to the powertrain to be located inside the arrangement. Additionally, at least part of the motor cover is no longer required, as the motor is housed between the inverter and the reduction gear transmission unit.

[0008] This invention relates to a powertrain comprising: an inverter unit including an inverter designed to convert direct current to alternating current and an inverter housing defining an inverter housing cavity that houses the inverter; and an electric motor including a rotor and a stator and an electric motor housing, the rotor defining a motor axis and the electric motor being designed to provide torque; a reduction gear drive unit including a reduction gear and a reduction gear cover surrounding the reduction gear, the reduction gear defining an output reduction gear axis, wherein the output reduction gear axis is parallel to the motor axis, the reduction gear cover and the inverter housing being arranged at opposite ends of the electric motor about the motor axis, and the inverter housing including a notch defining a notch region completely contained within a convex hull of the inverter housing, wherein the notch region is detached from the inverter housing cavity, and the output reduction gear axis passes through the notch region but not through the inverter housing cavity.

[0009] The arrangement of the powertrain according to the above-described concept of the invention offers numerous advantages. The notch allowing the output reduction gear shaft to penetrate the inverter housing allows for a reduction in the axial length of the powertrain, thus enabling a smaller installation length when the inverter housing is manufactured in a flattened manner. This notch also allows for a compact size design, as the output reduction gear shaft can be positioned close to the motor housing without colliding with the inverter housing. The parallel motor and output reduction gear shafts allow for a compact powertrain with similar spatial dimensions along its three independent axes in a Cartesian coordinate system. This compact powertrain can be easily integrated into a vehicle.

[0010] In one embodiment of the powertrain of the present invention, the inductive charging module is rigidly attached to at least one of: a) an electric motor housing, b) an inverter housing, c) a reduction gear cover, and the electric motor and the inductive charging module are designed to use the inverter.

[0011] Inductive charging modules can generally be combined with external modules typically installed outside electric vehicles. The external module generates a time- and space-varying electromagnetic field, which induces a current in the inductive charging module. The inductive charging module can be attached without backlash to at least one of the following: a) the motor housing, b) the inverter housing, and c) the reduction gear cover.

[0012] Inductive charging modules are typically used in conjunction with a rectifier to convert induced alternating current into direct current, thereby allowing the battery to be charged, for example. On the other hand, electric motors generally require an inverter to convert the direct current from the battery into alternating current to power a three-phase motor. The inverter may, for example, include silicon carbide (SiC) MOSFETs, which can be used bidirectionally; the same MOSFETs are used for both rectification and conversion. Often, some power electronics and circuitry used to control the motor (or, for example, for regeneration) can also be used in inductive charging modules.

[0013] Attaching the inductive charging module to the motor housing and / or inverter housing and / or reduction gear cover results in better overall powertrain integration. Because the inductive charging module can be attached to the motor housing and / or inverter housing and / or reduction gear cover, powertrain vibrations or overall motion similarly affect the motor housing and / or inductive charging module and / or inverter housing and / or reduction gear cover. The motor housing and / or inverter housing and / or reduction gear cover can also additionally cool the inductive charging module, especially when the motor housing and / or inverter housing and / or reduction gear cover are made of thermally conductive materials. Attaching the inductive charging module to the motor housing and / or inverter housing and / or reduction gear cover also reduces the number of connectors required for the inductive charging module.

[0014] In another embodiment of the powertrain of the present invention, the inductive charging module is substantially attached to one side of the motor housing and / or inverter housing and / or reduction gear cover, wherein the inductive charging module is particularly attached to the bottom side of the connector, wherein the bottom refers to the side after the powertrain is integrated into the electric vehicle.

[0015] The bottom side of the connector faces the ground. Because the external modules of an electric vehicle are generally installed in the ground, the inductive charging module can face the external modules.

[0016] In another embodiment of the powertrain of the present invention, the powertrain includes only one external connection component to an external battery.

[0017] In one embodiment of the powertrain of the present invention, the electric motor, the motor housing, and the reduction gear are housed within a volume surrounded by a bulge of the reduction gear cover and the inverter housing.

[0018] A convex hull is the smallest set of convex shapes that contain these points. In this embodiment, the convex hull is defined by the reduction gear cover and the inverter housing. Because the powertrain is housed within the convex hull, the overall powertrain arrangement is ensured to be compact and, for example, can be constructed with substantially symmetrical spatial dimensions. For example, the invention allows for the arrangement of the motor or reduction gear, or both, with minimal protrusion, i.e., none of them protrude excessively (they must always be contained within a specific convex hull). A slight protrusion from the convex hull is understood to be covered by this embodiment of the invention.

[0019] In another embodiment of the powertrain of the present invention, the results of the orthogonal projection of the bulge of the gear reducer cover to the plane defined by the output gear reducer axis and the motor axis and the projection plane of the output gear reducer axis and the motor axis and the separate orthogonal projection of the bulge of the inverter housing have substantially similar dimensions and shapes, wherein the two orthogonal projection results substantially overlap in the projection plane, wherein the bulges of the gear reducer cover and the inverter housing are particularly substantially similar to cuboids.

[0020] Therefore, the specific description of the bulge, along with the specific description of the parallelism between the motor axis and the output reduction gear axis, ensures that the motor and reduction gear can be concealed by the reduction gear cover and the inverter housing, so that an observer looking at the inverter housing from the front, for example, cannot see the motor and reduction gear. Because there are no protruding parts, the entire powertrain can be easily integrated into the vehicle (the above considerations regarding small protrusions apply similarly here).

[0021] In another embodiment, the notch area is substantially in the form of a cylindrical body, a conical body, or a square body or elongated hole with rounded edges, wherein the inverter housing is morphologically equivalent to a torus.

[0022] In another embodiment, the powertrain includes at least two external interfaces for mechanical energy transmission, one of which is located in the notch area.

[0023] The external interface for mechanical energy transmission can be provided in the form of a shaft joint, especially a flange. Other types of shaft joints are also possible (e.g., clamp joints, U-joints, flexible joints, toothed joints, etc.).

[0024] In another embodiment, the reduction gear includes at least first and second reduction gear stages and a differential, wherein at least one of the two reduction gear stages is implemented in the form of a spur gear. The other gear stage of the reduction gear can be implemented in the form of, for example, a planetary gear, a bevel gear, or a spur gear.

[0025] In another embodiment, at least one non-mechanical power transmission external interface of the powertrain is located between the inverter unit and the reduction gear transmission unit, wherein the at least one non-mechanical power transmission external interface is located on those portions of the inverter housing or the motor housing within the bulges of the reduction gear cover and the inverter housing. The non-mechanical power transmission external interface may be provided, for example, in the form of an electrical plug connection or a plugless fixed electrical connection mechanism for connecting the powertrain to a power source.

[0026] Utilizing the space between the inverter unit and the reduction gear is optimal, as it facilitates powertrain integration into the vehicle. This space can be optimally utilized if the free space within the powertrain is exhausted for external non-mechanical power transmission interfaces. This simplifies overall integration. Considering the minimum required cable bending radius, this space can, for example, be used for the optimal placement of cables connecting the powertrain to the power source.

[0027] In another embodiment, the parallel misalignment of the output reduction gear axis relative to the motor axis is determined by the stator diameter, wherein the ratio of the misalignment of the output reduction gear axis relative to the motor axis to the stator diameter has a value between 0.5 and 1.0, particularly between 0.6 and 0.8.

[0028] In another embodiment, the inverter includes a set of electrical components located in the intersecting volume of a first half-space defined by a hypothetical plane and the inner cavity of the inverter housing. The hypothetical plane is orthogonal to the plane defined by the output reduction gear axis and the motor axis and includes the output reduction gear axis, wherein the motor is located within the first half-space.

[0029] In another embodiment, the inverter includes at least one additional electrical component disposed within the intersection volume of a second half-space defined by a hypothetical plane and the inner cavity of the inverter housing, the second half-space being uniquely determined by the selection of a first half-space, wherein the combination of the first and second half-spaces corresponds to a complete three-dimensional space.

[0030] For example, this arrangement of the inverter unit components optimally utilizes the space provided by the cuboid, in which the powertrain can, for example, be located. Because there is generally a certain space between the output reduction gear axis and the surface of the cuboid containing the powertrain, this space can, for example, be used to position the inverter unit components within it.

[0031] In another embodiment, the inverter includes a first group and a second group of electrical components, each group including at least one capacitor, at least three power switches, at least three busbars, and a liquid cooling device. For each component in the first group, there is a corresponding twin component in the second group with substantially the same electrical performance. Each component in the first group and its twin component in the second group are arranged in twin positions within the inverter housing cavity about a plane defined by the output reduction gear axis and the motor axis. The twin positions are characterized in that the orthogonal projections of any component in the first group and its corresponding twin component in the second group onto the plane defined by the output reduction gear axis and the motor axis overlap and have substantially similar dimensions and shapes. The corresponding twin component is rotated to a certain extent in the space around its geometric center before the orthogonal projection, particularly, no rotation occurs on the corresponding twin component before the orthogonal projection.

[0032] These two sets of electrical components can be arranged, for example, in a mirror-image configuration. In this mirror-image configuration, the orientation and position of the second set of electrical components are obtained by reflecting the first set of electrical components onto a plane defined by the output reduction gear axis and the motor axis, which passes through the notch area. Instead of a reflected version of some of the electrical components of the first set, some of the electrical components of the second set can also correspond to translational and rotational versions of their counterparts in the first set. The direction of translation can be orthogonal to the plane defined by the output reduction gear axis and the motor axis, and the rotation of the electrical components can be understood about the geometric center, so that the rotation does not cause translation of the rotating electrical components.

[0033] In another embodiment, the powertrain includes a first liquid cooling circuit designed to cool the electrical components of the inverter and the stator of the motor. The first liquid cooling circuit can, for example, be a water-cooled circuit (wherein the water may contain other substances and / or additives such as monoethylene glycol or other refrigerants).

[0034] In another embodiment, the powertrain further includes a second liquid cooling circuit designed to cool the reduction gear drive unit and the rotor and / or rotor of the electric motor. The powertrain also includes a heat exchanger designed to exchange heat between the first and second liquid cooling circuits, wherein the heat exchanger is located within a volume surrounded by a bulge of the reduction gear cover and the inverter housing.

[0035] In this embodiment, the bulge is defined by the reduction gear cover and the inverter housing. The second liquid cooling circuit can be implemented, for example, as an oil cooling circuit. The second liquid cooling circuit can cool both the rotor and the stator windings (or winding ends).

[0036] In another embodiment, the first liquid cooling circuit and / or the second liquid cooling circuit are further designed to cool the inductive charging module.

[0037] The first and / or second liquid cooling circuits are additionally designed to cool the inductive charging module. The first liquid cooling circuit can be implemented, for example, as a water-cooled circuit (where the water may contain other substances and / or additives, such as monoethylene glycol or other refrigerants), or as an oil-cooled circuit. The addition of the powertrain can result in a reduction in the number of cooling devices required as cooling circuits for cooling the motor and / or inverter, and / or the reduction gear unit can also be used to cool the inductive charging module.

[0038] In another embodiment, the inductive charging module includes electrical wiring designed to generate an induced voltage, and the inductive charging module includes an inductive charging module housing having a first side facing the motor housing and / or inverter housing and / or reduction gear cover, wherein the cooling liquid used for the first or second liquid cooling circuit is designed to flow along the first side of the inductive charging module housing, especially when in contact with the first side of the inductive charging module housing, and the cooling liquid is designed to pass through at least a portion of at least one of the motor and inverter, especially the cooling liquid is designed to submerge at least a portion of at least one of the motor and inverter in the cooling liquid.

[0039] The inductive charging module may include an inductive charging module channel in the inductive charging module housing, particularly on the first side of the inductive charging module housing, through which cooling liquid can flow. The inductive charging module channel may be continuously connected to a cooling channel designed for cooling the motor and / or inverter and / or reduction gear transmission unit, which is a first and / or second liquid cooling circuit.

[0040] The at least one liquid cooling circuit can cool the inductive charging module. The at least one liquid cooling circuit can be implemented, for example, as a water-cooled circuit (wherein the water may also contain other substances and / or additives, such as monoethylene glycol or other refrigerants). The inclusion of the powertrain of this invention may reduce the number of cooling devices required. Cooling circuits used for cooling inverter components and the stator can also be used, for example, for the inductive charging module.

[0041] The inductive charging module may include magnetic components and electronic components. The magnetic components and electronic components may also be cooled using different liquid cooling circuits.

[0042] In another embodiment, an electromagnetic compatibility (EMC) filter is installed in the inverter housing.

[0043] The EMC filter can be mounted close to the additional inverter components, or the additional inverter components may contain the EMC filter. In this embodiment of the invention, a compact volume housing the powertrain is optimally utilized.

[0044] In another embodiment, the maximum speed of the motor is designed to be between 12,000 rpm and 25,000 rpm.

[0045] High speeds per minute are possible with electric motors because the entire powertrain has a compact size. Smaller motors generally allow for higher speeds. For example, a motor with a stator diameter of 200 mm can be designed to have a maximum speed of 24,000 rpm. Motors with larger stator diameters generally only allow for lower maximum speeds.

[0046] The present invention relates to electric vehicles, which include a powertrain in which drive wheels are connected to each mechanical energy transmission external interface via drive shafts. Attached Figure Description

[0047] The system of the present invention will be described in more detail below with the aid of specific embodiments illustrated in the figures, and other advantages of the present invention will also be demonstrated. Identical components are indicated by the same reference numerals in the figures, specifically:

[0048] Figure 1 A schematic diagram of the powertrain arrangement of the present invention is shown.

[0049] Figure 2 This shows a front view of the inverter unit of the present invention.

[0050] Figure 3 This view shows the result of separate orthogonal projections of the bulge of the reduction gear cover and the bulge of the inverter housing onto the same plane.

[0051] Figure 4The powertrain arrangement of the present invention, which includes an inductive charging module, is shown.

[0052] Figure 5 Another view shows the powertrain arrangement of the present invention with an inductive charging module. Detailed Implementation

[0053] Figure 1 A schematic diagram of the powertrain arrangement according to the invention is shown. A stator 1 and a rotor 2 (with the rotor 2 defining the motor shaft 3) are mounted therein, positioned between a reduction gear transmission unit 6 and inverter units 4, 5, and 16. The reduction gear transmission unit includes a reduction gear cover 6a, reduction gears 7, 17, and 18, and a differential 14. Inverter units 4, 5, and 16 include an inverter housing 4 and inverters 5 and 16 mounted within the inverter housing 4. The inverter housing 4 is composed of a housing portion 4a and a housing cover 4b. Inverters 5 and 16 include (among other optional components not further specified herein) a first set of components 5 adjacent to the stator 1 and additional components 16. An EMC filter 28 is also disposed adjacent to the additional components 16, or alternatively, the additional components 16 include an EMC filter 28. The first set of components 5 of the inverter includes a first set of electrical components 5a and a second set of electrical components 5b. Both the first group of electrical components 5a and the second group of electrical components 5b include the same number of electrical components, wherein each group 5a, 5b includes at least one capacitor 20a, 20b, at least three power switches 21a, 21b, at least three busbars 22a, 22b, and liquid cooling devices 23a, 23b. The overall assembly of these groups of electrical components 5a, 5b may be mirror-image, with the twin electrical components 5b of the second group 5b at the mirror position belonging to each electrical component of the first group 5a. In a particularly advantageous configuration, each group 5a, 5b includes three capacitors 20a, 20b, six power switches 21a, 21b, three busbars 22a, 22b, and one liquid cooling device 23a, 23b.

[0054] This mirrored configuration divides the total inverter current in half within each inverter section. This allows for a reduction in the current intensity in inverter units 4, 5, and 16 compared to prior art inverters, while the mirrored inverter units 4, 5, and 16 achieve a similar total power density as prior art, where the power density is defined as the total power provided by inverter units 4, 5, and 16 divided by the volume enclosed by inverter housing 4. The smaller current density in inverter units 4, 5, and 16 minimizes undesirable effects such as the total voltage caused by parasitic inductance in inverter units 4, 5, and 16, thereby improving the switching performance of the inverter semiconductors. A larger current density would also require a larger wire cross-section. Reducing the current density is therefore technically advantageous.

[0055] The reduction gear transmission unit 6 defines an output reduction gear axis 15 passing through the differential 14. The output reduction gear axis 15 is parallel to the motor axis 3. The output reduction gear axis 15 passes through the inverter housing 4, which has a notch 10, through which the output reduction gear axis 15 passes. An external mechanical energy transmission interface 11 is installed within the notch area, which is implemented, particularly in the form of a flange, providing the possibility of attaching an output shaft to the powertrain. Another external mechanical energy transmission interface 12 is provided at the other end of the output reduction gear axis 15, which is also implemented, particularly in the form of a flange. These two external mechanical energy transmission interfaces 11 and 12 are connected to the differential 14 via two output shafts 29a and 29b arranged coaxially with the output reduction gear axis 15. The two output shafts 29a and 29b transmit the mechanical energy supplied by the motors 1 and 2 to the differential 14 via at least two gear stages 17 and 18 to the two external mechanical energy transmission interfaces 11 and 12. The differential 14 allows the shafts connected to the two external mechanical energy transmission interfaces 11 and 12 to rotate at high speed.

[0056] Motors 1 and 2 are housed within motor housing 9. The non-mechanical energy transmission external interface 8 is located in the space between the reduction gear cover 6a and the inverter housing 4 that is not filled by the motor housing 9.

[0057] Figure 1 The powertrain includes two liquid cooling circuits 25 and 26. The first liquid cooling circuit 25 is designed to cool at least one of the heat-generating components of the inverters 5 and 16, as well as the stator 1, while the second liquid cooling circuit 26 is designed to cool the gear stages of the reduction gear unit 6 and parts of the motors 1 and 2 (e.g., winding heads and / or rotors). The liquids in the first cooling circuit 25 and the second cooling circuit 26 can exchange heat through a heat exchanger 27 that thermally connects the first liquid cooling circuit 25 and the second liquid cooling circuit 26.

[0058] Figure 2 A front view of inverter units 4, 5, and 16 is shown after the housing cover 4b has been removed. A mirrored assembly of six capacitors 20a and 20b, twelve power switches 21a and 21b, six busbars 22a and 22b, and two liquid cooling units 23a and 23b is shown (only one busbar is shown in the cut-out sectional view, as the busbar is located below the other components of the assembly). Regarding the reflection implied in the mirrored assembly by mirror 24, mirror 24 passes through notch 10 and is defined by the output reduction gear axis 15 and the motor axis 3. Notch 10, through which the output reduction gear axis 15 passes, is particularly cylindrical. The output shaft 29b (not shown in the figure), passing through the cylindrical notch 10, can be efficiently connected to an external mechanical energy transmission interface 1, particularly in the form of a flange. Figure 2 As shown, the first set of inverter components 5 is arranged close to the motors 1 and 2. The closeness is shown by the projection of the motor housing 9 onto a plane perpendicular to the mirror 24 and perpendicular to the output reduction gear axis 15 and the motor axis 3. The volume contained in the inverter housing 4 is efficiently utilized. Components of the inverter 5 and 16 are placed on both sides of the notch 10 (both sides are understood with respect to the hypothetical plane 19).

[0059] Figure 3 The diagram shows the result 30 of orthogonal projection of the convex hull of the reduction gear cover 6a onto a plane perpendicular to mirror 24 and assumed plane 19, and the result 31 of orthogonal projection of the convex hull of the inverter housing 4 onto a plane perpendicular to mirror 24 and assumed plane 19. The two orthogonal projections 30 and 31 have substantially similar dimensions and shapes and overlap. The projections 30 and 31 are substantially similar to rectangles. This is, in turn, a result of the fact that the convex hulls of the reduction gear cover 6a and the inverter housing 4 are substantially similar to cuboids.

[0060] Figure 4 The powertrain according to the invention is shown from the outside. The reduction gear cover 6a, the motor housing 9, and the inverter housing 4 with a notch 10 are visible. The inductive charging module 32 is in an extended shape as shown, under which the coil for inducing current is visible. The inductive charging module 32 is securely attached to the inverter housing 4. The first side 32a of the inductive charging module housing faces the reduction gear cover 6a, the motor housing 9, and the inverter housing 4.

[0061] Figure 5 The inverter housing 4, the motor housing 9, and the induction charging module housing containing the induction charging module components in a compressed form are shown, wherein the compressed form corresponds to... Figure 4 The diagram shows the expanded form after compression along an axis. The inductive charging module 32 is securely attached to the inverter housing 4. A cooling channel 33 for cooling fluid flow on the motor housing is also shown. The cooling channel can be continuously connected to an inductive charging module channel (not shown) arranged in the first side of the inductive charging module housing facing the motor housing 9.

[0062] It goes without saying that the figures shown are merely schematic diagrams of possible embodiments.

[0063] Although the invention has been illustrated above with reference to some preferred embodiments, it should be understood that many changes and combinations of different features of the embodiments can be made. All such changes are within the scope of the appended claims.

Claims

1. A powertrain, the powertrain comprising: Inverter unit, the inverter unit comprising an inverter designed to convert direct current to alternating current and an inverter housing (4) defining an internal cavity for accommodating the inverter, and An electric motor (1,2) comprising a rotor (2) and a stator (1) and an electric motor housing (9), the rotor (2) defining a motor axis (3) and the electric motor (1,2) designed to provide torque, and A reduction gear transmission unit (6) includes a reduction gear and a reduction gear cover (6a) surrounding the reduction gear, the reduction gear defining an output reduction gear axis (15). Its characteristics are, The output reduction gear axis (15) is parallel to the motor axis (3), and the reduction gear cover (6a) and the inverter housing (4) are arranged at opposite ends of the motor (1,2) about the motor axis (3), and the inverter housing (4) includes a notch (10), wherein the notch defines a notch area that is completely received within the bulge of the inverter housing (4), wherein the notch area is detached from the inner cavity of the inverter housing, and the output reduction gear axis (15) passes through the notch area without passing through the inner cavity of the inverter housing.

2. The powertrain according to claim 1, characterized in that, The inductive charging module (32) is rigidly attached to at least one of the following: The motor housing (9), The inverter housing (4), The reduction gear cover (6a) Furthermore, the motors (1,2) and the inductive charging module (32) are designed to use the inverter.

3. The powertrain according to claim 2, characterized in that, The inductive charging module (32) is attached to one side of the motor housing (9) and / or the inverter housing (4) and / or the reduction gear cover (6a).

4. The powertrain according to any one of the preceding claims, characterized in that, The powertrain includes only one external connection component leading to an external battery.

5. The powertrain according to claim 1, characterized in that, The motor (1,2), the motor housing (9) and the reduction gear are housed in a cavity surrounded by the bulge of the reduction gear cover (6a) and the inverter housing (4).

6. The powertrain according to claim 1, characterized in that, The notch area is implemented in the form of a cylindrical or conical body, a square body with rounded corners, or an elongated hole, wherein the inverter housing is morphologically equivalent to a toroidal surface.

7. The powertrain according to claim 1, characterized in that, The powertrain includes at least two external interfaces (11, 12) for transmitting mechanical energy, wherein one of the external interfaces (11, 12) is located in the notch region.

8. The powertrain according to claim 1, characterized in that, The reduction gear includes at least a first reduction gear stage (17) and a second reduction gear stage (18) and a differential (14), wherein at least one of the first reduction gear stage (17) and the second reduction gear stage (18) is implemented in the form of a spur gear (7).

9. The powertrain according to claim 1, characterized in that, At least one non-mechanical power transmission external interface (8) of the powertrain is located between the inverter unit and the reduction gear transmission unit (6), wherein the at least one non-mechanical power transmission external interface (8) is located on those portions of the inverter housing (4) or the motor housing (9) within the bulges of the reduction gear cover (6a) and the inverter housing (4).

10. The powertrain according to claim 1, characterized in that, The parallel misalignment of the output reduction gear axis (15) relative to the motor axis (3) is determined by the diameter of the stator (1), wherein the ratio of the misalignment of the output reduction gear axis relative to the motor axis (3) to the diameter of the stator (1) has a value between 0.5 and 1.

0.

11. The powertrain according to claim 1, characterized in that, The inverter includes a set of electrical components (5) located in the intersecting volume of a first half-space defined by a hypothetical plane (19) and the inner cavity of the inverter housing. The hypothetical plane (19) is orthogonal to the plane defined by the output reduction gear axis (15) and the motor axis (3) and includes the output reduction gear axis (15), wherein the motor (1,2) is located in the first half-space.

12. The powertrain according to claim 11, characterized in that, The inverter includes at least one additional electrical component (16) which is disposed within the intersection volume of a second half-space defined by the assumed plane (19) and the inner cavity of the inverter housing. The second half-space is uniquely determined by the selection of the first half-space, wherein the combination of the first half-space and the second half-space corresponds to a complete three-dimensional space.

13. The powertrain according to claim 2, characterized in that, The powertrain includes a first liquid cooling circuit (25) designed to cool the electrical components of the inverter and the stator (1) of the motor (1,2).

14. The powertrain according to claim 13, characterized in that, The powertrain also includes: A second liquid cooling circuit (26) is designed to cool the reduction gear transmission unit (6) and the rotor (2) and / or stator (1) of the motor (1,2), and A heat exchanger (27) is designed to exchange heat between the first liquid cooling circuit (25) and the second liquid cooling circuit (26), wherein the heat exchanger (27) is located within a volume surrounded by the bulge of the reduction gear cover (6a) and the inverter housing (4).

15. The powertrain according to claim 14, characterized in that, The first liquid cooling circuit (25) and / or the second liquid cooling circuit (26) are further designed to cool the inductive charging module (32).

16. The powertrain according to claim 15, characterized in that, The inductive charging module (32) includes electrical wiring designed to generate an induced voltage, and the inductive charging module (32) includes an inductive charging module housing having a first side (32a) of the inductive charging module housing facing the motor housing and / or the inverter housing and / or the reduction gear cover, wherein the cooling liquid used in the first liquid cooling circuit (25) or the second liquid cooling circuit (26) is designed to flow along the first side (32a) of the inductive charging module housing, and wherein the cooling liquid is designed to pass through at least a portion of at least one of the motor (1,2) and the inverter.

17. The powertrain according to claim 1, characterized in that, An electromagnetic compatibility filter (28) is installed in the inverter housing (4) and / or the maximum speed of the motor (1,2) is designed to be between 12,000 rpm and 25,000 rpm.

18. The powertrain according to claim 3, characterized in that, The inductive charging module (32) is attached to the bottom side of the connector, where the bottom refers to the side of the powertrain after it is integrated into the electric vehicle.

19. The powertrain according to claim 10, characterized in that, The ratio of the misalignment of the output reduction gear axis relative to the motor axis (3) to the diameter of the stator (1) is between 0.6 and 0.

8.

20. The powertrain according to claim 16, characterized in that, The cooling liquid used in the first liquid cooling circuit (25) or the second liquid cooling circuit (26) is designed to flow along the first side (32a) of the inductive charging module housing by contacting the first side (32a) of the inductive charging module housing.

21. The powertrain according to claim 16, characterized in that, The cooling liquid is designed to submerge at least a portion of at least one of the motors (1,2) and the inverter in the cooling liquid.

22. An electric vehicle comprising a powertrain according to any one of the preceding claims, characterized in that, The drive wheels are connected to each mechanical energy transmission external interface (11, 12) via drive shafts.

Images