Multi-body housing for an electric powertrain with a reduced axial installation length

Abstract

The invention relates to a multi-body housing (11) for an electric powertrain (200), comprising a first housing part which forms one or more compartments (10, 75) for receiving components of the electric powertrain (200), said one or more compartments (10, 75) comprising a first compartment (10) for receiving a first component, which is provided as an electric motor (1) with a motor shaft (55), and comprising a second housing part, which forms a plurality of fluid passages for conducting a cooling and / or lubricating fluid. The second housing part is designed to evacuate the cooling and / or lubricating fluid out of the compartment or the plurality of compartments (10, 75) by means of a pressure gradient along at least one fluid passage of the plurality of fluid passages, said pressure gradient being generated by means of the rotation of the motor shaft (55) and / or by means of the rotation of a counterpart of the motor shaft (55) when the electric motor (1) is in a switched-on state. The housing (11) comprises, as an integral component, a fluid trough (76, 77) for receiving the cooling and / or lubricating fluid from the plurality of fluid passages, and the first compartment (10) is fluidically coupled to the fluid trough (76, 77) via at least one fluid passage of the plurality of fluid passages. The invention further relates to an electric powertrain comprising an electric motor and such a multi-body housing and to an at least partly electrified vehicle comprising such an electric powertrain.

Description

[0001] Multi-body housing for an electric drive train with reduced axial length

[0002] The present invention relates to a multi-body housing for an electric drive train in an at least partially electrified vehicle. The present invention further relates to an electric drive train comprising an electric motor and such a housing. The present invention further relates to an at least partially electrified vehicle having such an electric drive train.

[0003] Purely electric vehicles and hybrid electric vehicles, which are powered exclusively or with the assistance of one or more electric motors as drive units, are known from the prior art. To supply the electric motors with electrical energy, the electric vehicles include electrical energy storage devices, in particular rechargeable batteries or secondary batteries. These batteries are designed as direct current sources. However, the electric machines generally require alternating current. Therefore, a DC / AC inverter with semiconductor-based power electronics is usually connected between the battery and the electric motor to convert the DC input voltage into an AC output voltage and thus operate the electric motor.

[0004] During operation of the electric motor, copper losses occur on the motor side, while conduction and switching losses occur on the inverter side. The resulting heat can lead to overheating and thus to thermal damage to the motor components and the inverter. This is particularly the case in electric vehicles powered by high-voltage batteries with output voltages of up to 800 V. Cooling systems are therefore used that use a cooling fluid, such as oil. Such cooling systems comprise several oil passages connecting various cavities of the electric drivetrain, as well as a reservoir. US8746405B2 discloses a transaxle with a differential sump in which a gear is used to drain the oil into the oil sump. The oil flows through an opening under the influence of gravity into the oil sump to lubricate the gear bearings.US9903242B2 discloses a dry oil sump in which a suction pump is used to remove the oil from the oil sump and transfer it to the oil reservoir.

[0005] In known cooling systems, the electric motor or its components cannot be properly cooled by oil circulation. This results in the electric motor being exposed to at least partial overheating, which thermally limits the continuous performance of the electric motor. Furthermore, the known systems require a relatively large axial length, which is disadvantageous in terms of system compactness, especially in applications where a lower drivetrain height is critical, such as sports cars. In addition, the problem of oil slinging within the oil sump remains unsolved in known systems.

[0006] It is therefore the object of the present invention to provide an improved or at least alternative cooling solution for an electric drive train, with which the above-mentioned disadvantages are at least partially overcome.

[0007] The above-mentioned technical problem is solved by the multi-body housing for an electric drive train according to claim 1, an electric drive train for an at least partially electrified vehicle according to claim 14, and an at least partially electrified vehicle according to claim 15. Advantageous embodiments are the subject of the dependent claims.

[0008] The present invention is based on the finding that essential parts of the system for supplying a cooling and / or lubricating fluid to components of an electric drive train can be arranged on one side of the electric motor or a compartment accommodating the electric motor and thus in the immediate vicinity of the electric motor in order to improve the cooling of the components or assemblies of the electric drive train and additionally to make the electric drive train more compact.

[0009] The multi-body housing for the electric drive train comprises a first housing part in which at least one compartment (receiving compartment or housing compartment) is formed, preferably in which a plurality of compartments or receiving compartments are formed, each of which is designed to receive a component of the electric drive train that requires cooling and / or lubrication. The components can in particular comprise an electric motor, a transmission and / or an inverter. A first compartment of the one or more compartments of the first housing part is designed to receive a first component formed as an electric motor with a motor shaft. A second housing part of the multi-body housing forms a plurality of fluid passages for guiding a cooling and / or lubricating fluid (i.e., a fluid that can be used as a coolant and / or lubricant).A preferred example of the cooling and / or lubricating fluid is a mixture of a dielectric fluid, in particular an oil, and air. The fluid passages are arranged such that they fluidly connect the compartments to one another and to a fluid trough designed to receive the cooling and / or lubricating fluid from the fluid passages. The second housing part is further configured to evacuate the cooling and / or lubricating fluid from at least one, preferably all, of the plurality of compartments to the fluid trough through a pressure gradient along at least one of the plurality of fluid passages.

[0010] The use of pressure gradients improves the transport rate of the coolant and / or lubricant, thereby improving the performance and endurance of electrical and mechanical components of the electric powertrain. The pressure gradient is created by the rotation of the motor shaft and / or by the rotation of a motor shaft counterpart (such as an impeller) when the electric motor is in an energized state. This improves the transport rate of the coolant and / or lubricant and thus the efficiency of cooling and / or lubrication, thereby improving the performance and durability of the electric powertrain. Furthermore, by utilizing the rotation of the motor shaft and / or the rotation of the motor shaft counterpart, the need for auxiliary external equipment such as a suction pump is eliminated, thus minimizing the number of moving parts in the electric powertrain that are prone to maintenance and failure.

[0011] The fluid pan (or fluid sump) forms an integral component (or an integral part) of the multi-body housing. The fluid pan is therefore substantially, preferably entirely, contained within the multi-body housing. This makes it possible to place the space-consuming fluid pan in the immediate vicinity of the main location of the cooling and / or lubricating fluid within the multi-body housing, resulting in a compact, space-saving, preferably cubic design of the multi-body housing and / or the electric drive train. Advantageously, the axial dimension or overall length of the electric drive train, which corresponds, for example, to the height of the multi-body housing, can be reduced or even minimized. This enables or facilitates the installation of the electric drive train in vehicles for which a low center of gravity is important and / or in vehicles with tight installation spaces, such as sports cars.The compact design of the multi-body enclosure also enables a significant reduction in the number and / or dimensions of parts such as tubes, hoses, fasteners, connectors and highly integrated components, which in turn increases robustness and reduces the risk of failures over the lifetime of the electric powertrain.

[0012] According to one aspect of the present disclosure, the fluid pan is arranged on an outer side of the electric motor and / or on an outer side of the first compartment, preferably wherein the fluid pan is arranged on a left outer side or a right outer side of the electric motor and / or on a left outer side or a right outer side of the first compartment (left / right with respect to the viewing direction along the axial direction of the electric motor). In the context of the present disclosure, the outer side of the electric motor is preferably a circumferential side, more preferably a circumferential surface thereof, wherein the outer side of the first compartment is preferably a circumferential side, more preferably a circumferential surface thereof. Arranging the fluid pan on the outer or circumferential side / circumferential surface of the electric motor and / or the first receiving compartment, preferably in such a way that the fluid pan is connected to the respective outer side, in particular the circumferential side orcircumferential surface, for example substantially at the same or a greater distance from the underbody of the vehicle as / than the electric motor or the first receiving compartment, enables at least partial flow of the cooling and / or lubricating fluid through the electric motor or the first compartment even when the electric motor is switched off. This also ensures improved cooling and / or lubrication of the electric motor and possibly other components of the electric drive train accommodated in other compartments of the first housing part, such as the transmission and the inverter, when the electric motor is switched on. In this way, power losses that arise because the electric motor is subjected to a high load, for example due to rapid acceleration after a traffic light has turned green, can be reduced or even avoided according to the invention.It is preferred to arrange the fluid passages, by means of which the first compartment and the fluid pan are fluidically coupled to one another, on an outer side (or circumferential side / circumferential surface) of the electric motor and / or the first receiving compartment, for example, at substantially the same or a greater distance from the underbody of the vehicle as / than the electric motor or the first receiving compartment. The present arrangement further allows the space-consuming fluid sump to be placed in the immediate vicinity of the main location of the cooling and / or lubricating fluid within the multi-body housing, resulting in a more compact, space-saving, preferably cubic design of the electric drive train, the shortest side of which corresponds to the axial height of the multi-body housing.This enables the installation of the electric drive train in vehicles for which a low center of gravity is particularly important and facilitates its installation in vehicles with tight installation spaces, such as sports cars. Furthermore, no fluid pump is required to maintain a predetermined filling of the compartments, in particular the first compartment, with the cooling and / or lubricating fluid. According to one aspect of the present disclosure, the fluid pan is arranged on an upper outer side, in particular an upper circumferential side or upper circumferential surface, of the electric motor and / or the first compartment with respect to a direction of gravity.This measure ensures that the hydrostatic pressure of the cooling and / or lubricating fluid in the fluid pan is sufficiently high to at least partially flow the cooling and / or lubricating fluid through the first compartment, and optionally also through other compartments such as the compartment accommodating the transmission and / or another compartment accommodating the inverter, even when the vehicle is out of operation, e.g., at a standstill. This makes it possible to build up high rotational power without any time delay after starting the electric motor, particularly until a sufficient pressure gradient is reached to ensure effective circulation of the cooling and / or lubricating fluid. Furthermore, the fluid pan is preferably used as an oil tank or reservoir, thus eliminating the need for an additional / external reservoir for degassing / defoaming the oil.

[0013] According to one aspect of the present disclosure, the fluid pan has a volume, wherein at least 10% of the volume is located on the upper outer side, in particular the upper circumferential side or circumferential surface, of the electric motor and / or the first compartment with respect to the direction of gravity. Preferably, at least 25%, at least 50%, at least 75%, and more preferably 100% of the volume is located on the upper outer side, in particular the upper circumferential side or circumferential surface, of the electric motor and / or the first compartment with respect to the direction of gravity. This additionally ensures sufficient cooling and / or lubrication of the electric motor when starting the vehicle.

[0014] According to one aspect of the present disclosure, the plurality of fluid passages comprise a first fluid inlet passage for providing the cooling and / or lubricating fluid from the fluid pan to the first compartment, wherein the first fluid inlet passage is arranged at an elevated position relative to the motor shaft, preferably relative to a central axis of the motor shaft, with respect to the direction of gravity. The first fluid inlet passage is designed to provide a continuous gradient from the fluid pan to the first receiving compartment. The first fluid inlet passage is further configured to fluidically connect the first compartment receiving the electric motor to the pressure side of a fluid supply of the cooling and / or lubricating fluid, e.g., an oil pump. This arrangement of the first fluid inlet passage, and optionally the fluid pan (i.e.,on an upper outer side, in particular an upper circumferential side Z-surface, of the electric motor and / or the first compartment with respect to the direction of gravity) ensures that the electric motor is sufficiently supplied with the cooling and / or lubricating fluid even when the electric motor is switched off or in standby mode.

[0015] According to one aspect of the present disclosure, the plurality of fluid passages comprise a first fluid outlet passage for providing the cooling and / or lubricating fluid from the first compartment to the fluid pan, wherein the first fluid outlet passage is arranged at an elevated position relative to the motor shaft, in particular relative to the central axis of the motor shaft. The first fluid outlet passage can provide a continuous gradient from the fluid pan to the first compartment. The first fluid outlet passage can be configured such that it fluidically connects the first compartment to a suction side of the fluid supply directly or via another compartment for accommodating another component of the electric drive train, such as a transmission and / or an inverter. This arrangement of the first inlet fluid passage, and optionally the fluid pan (ieon an upper outer side, in particular an upper circumferential side (Z-surface), of the electric motor and / or the first compartment with respect to the direction of gravity), prevents fluid emptying of the electric motor by partially or completely discharging the cooling and / or lubricating fluid when the electric motor is switched off or in standby mode. The first fluid outlet passage and / or the first fluid inlet passage, in particular the first fluid inlet passage and the first fluid outlet passage, are preferably arranged at an elevated position relative to the motor shaft, in particular its central axis, which is defined with respect to the direction of gravity.

[0016] According to one aspect of the present disclosure, the first housing part comprises a second compartment for receiving a second component, which may be the transmission (or a transmission set comprising multiple transmissions) with a transmission shaft, wherein the second compartment is fluidly coupled to the fluid pan via at least one of the plurality of fluid passages. The at least one fluid passage may have a second fluid inlet passage for supplying the cooling and / or lubricating fluid to the second compartment, wherein the second fluid inlet passage fluidly connects the second compartment to the fluid pan and / or the second compartment. Alternatively or additionally, the at least one fluid passage may have a second fluid outlet passage for discharging the cooling and / or lubricating fluid from the second compartment, wherein the second fluid outlet passage fluidly connects the second compartment to the fluid pan.The second fluid inlet passage and / or the second fluid outlet passage are preferably arranged at an elevated position relative to the motor shaft, in particular its central axis, and / or relative to the transmission, in particular its transmission shaft, with respect to the direction of gravity. This ensures that cooling and / or lubricating fluid can be supplied to the second compartment of the multi-body housing even when the vehicle is not in operation. The transmission can thus be sufficiently supplied with the cooling and / or lubricating fluid even when the electric motor is stationary or in standby mode.

[0017] According to one aspect of the present disclosure, the second compartment is connected to the first compartment via another (e.g., the second) fluid inlet passage, which is preferably arranged at an elevated position relative to the motor shaft with respect to the direction of gravity. This ensures that cooling and / or lubricating fluid can be supplied to the second compartment even when the vehicle is not in operation. The transmission can thus be sufficiently supplied with the cooling and / or lubricating fluid even when the electric motor is stationary or in standby mode.

[0018] According to one aspect of the present disclosure, the pressure gradient is selected to evacuate a first portion of the cooling and / or lubricating fluid guided from the first compartment, in particular from a circulation chamber formed in the first compartment, into the second compartment serving to accommodate the transmission via a first fluid passage extending in the axial direction relative to the motor shaft. Alternatively or additionally, the pressure gradient is selected to evacuate a second portion of the cooling and / or lubricating fluid guided from the first compartment, in particular from the circulation chamber, to the fluid pan via a second fluid passage extending in the radial direction relative to the motor shaft. The first fluid passage can be the second fluid inlet passage. The second fluid passage can be the first fluid outlet passage. This enables the control of the quantity of cooling and / or lubricating fluid according to the general, and optionally also the specific, requirements of the components.

[0019] According to a further aspect of the disclosure, the cooling and / or lubricating fluid comprises a mixture of oil and air, wherein the fluid pan is designed as an oil pan and the second housing part has a mixing chamber for providing the oil-air mixture, wherein the plurality of fluid passages comprises a first air inlet passage for supplying oil from the oil pan via the mixing chamber to the first compartment, wherein the mixing chamber has an air inlet passage for supplying air to the mixing chamber. The mixture of oil and air as cooling and / or lubricating fluid enables minimization of hydrostatic losses or hydraulic flow resistance, particularly in the gap between the rotor and stator of the electric motor.

[0020] The first fluid inlet passage, the second fluid inlet passage, the first fluid outlet passage and / or the second fluid outlet passage may be formed as a nozzle, opening or bore or may comprise a nozzle, opening or bore.

[0021] A preferred example of the first fluid inlet passage comprises a mixing chamber in which, when the oil-air mixture is used as cooling and / or lubricating fluid, the oil and the air are mixed. The mixing chamber can be designed to provide a fluidic connection between the fluid pan and the first compartment. A preferred example of the second fluid inlet passage comprises a first axial passage which extends in the axial direction and is raised relative to the motor shaft (or its central axis), and runs substantially parallel to the central axis, in order to distribute the cooling and / or lubricating fluid from a circulation chamber, for example an A-side circulation chamber described in more detail below, to the second compartment. A preferred example of the first fluid outlet passage comprises a first axial passage which extends in the radial direction and is raised relative to the motor shaft (or its central axis).A preferred example of the second fluid outlet passage comprises a second radial passage which extends in the radial direction and is elevated relative to the motor shaft (or its central axis) and is substantially perpendicular to the central axis in order to distribute the cooling and / or lubricating fluid from a circulation chamber, in particular the A-side circulation chamber, to the fluid pan. A preferred example of the second fluid outlet passage comprises a second radial passage which extends in the radial direction and is elevated relative to the motor shaft (or its central axis) and is substantially perpendicular to the central axis in order to distribute the cooling and / or lubricating fluid from the second compartment to the fluid pan. Alternatively or additionally, the second radial passage can initially distribute the cooling and / or lubricating fluid from the first compartment to one or more further compartments and finally to the fluid pan. In this way, the second radial passage can also fulfill the combined fluid guiding function of the first and second fluid outlet passages.Another example of the second fluid outlet passage includes an oil channel that fluidly connects the second compartment to the fluid pan.

[0022] According to one aspect of the present disclosure, a cross-sectional size ratio, in particular a diameter ratio, between a first cross section of the first fluid outlet passage and a second cross section of the second fluid inlet passage is selected to be proportional to a flow ratio (or flow rate ratio) between a first (e.g., preset) flow rate of the cooling and / or lubricating fluid for the electric motor (i.e., the fluid guided in the region of the electric motor) and a second (e.g., preset) flow rate of the cooling and / or lubricating fluid for the transmission (i.e., the fluid guided in the region of the transmission).Preferably, the dimension of the first cross-section (in particular its first diameter) is assigned to a first part of the cooling and / or lubricating fluid guided out of the first compartment, while the dimension of the second cross-section (in particular its second diameter) is assigned to a second part of the cooling and / or lubricating fluid guided out of the first compartment. The first fluid outlet passage can be fluidically coupled to the second fluid inlet passage and thus provide a direct fluid connection between the first compartment and the fluid trough. The cross-sectional size ratio or the diameter ratio can either be fixed, e.g. by using fluid outlet passages with a defined cross-section. The flow ratio between the flow rates can generally be defined by the ratio of the opening cross-sections between the first raised radial passage and the first raised axial passage.The cross-section for both passages (i.e., the first fluid outlet passage and the second fluid inlet passage) can be in a range between 30 mm2 and 3,000 mm2, such as between 50 mm2 and 1,000 mm2 or between 100 mm2 and 500 mm2. Alternatively, the diameter ratio can be designed to be controllable or adjustable, e.g., depending on the temperature (or temperature changes) of the electric motor and / or the cooling and / or lubricating fluid located in the first compartment, and / or depending on the temperature (or temperature changes) of the gearbox and / or the cooling and / or lubricating fluid located in the second compartment accommodating the gearbox.For example, nozzles with controllable cross-section adjustment can be used, which can be automatically controlled in response to a temperature detected in the first and second compartments and / or a temperature of the cooling and / or lubricating fluid detected immediately after the first and second compartments, e.g., in the first fluid outlet passage and the second fluid outlet passage. This ensures proper distribution of the cooling and / or lubricating fluid between the various compartments and parts of the electric powertrain according to the actual cooling and / or lubrication requirements.

[0023] According to one aspect of the present disclosure, the pressure gradient is adapted to evacuate a first portion of the cooling and / or lubricating fluid guided from the first compartment, in particular from a circulation chamber formed in the first compartment, to the second compartment serving to accommodate the transmission via a first fluid passage extending in the axial direction relative to the motor shaft. Alternatively or additionally, the pressure gradient is adapted to evacuate a second portion of the cooling and / or lubricating fluid guided from the first compartment, in particular from the circulation chamber, to the fluid pan via a second fluid passage extending in the axial direction relative to the motor shaft.The first and / or second part of the cooling and / or lubricating fluid guided from the first compartment, in particular from the circulation chamber, can be evacuated using a cross-sectional size or diameter ratio between the first outlet fluid passage and the second inlet fluid passage, which is selected to be proportional to a flow ratio (flow rate ratio) between a (e.g. preset) first flow rate of the cooling and / or lubricating fluid acting in the region of the electric motor and a (e.g. preset) second flow rate of the cooling and / or lubricating fluid acting in the region of the transmission, as stated above.

[0024] According to one aspect of the present disclosure, the first housing part of the present multi-body housing may comprise a plurality of compartments connected in parallel, in series, or in a combination thereof, preferably via the second housing part and / or a further housing part, such as a third housing part. This enables various configurations for supplying the cooling and / or lubricating fluid to the components of the electric drive train accommodated in the various compartments. For example, the second housing part may have a plurality of inlets and / or outlets for circulating the cooling and / or lubricating fluid, for example in the first compartment and optionally in the second and further compartments, wherein the inlets may be connected in parallel and / or in series, and the outlets may be similarly connected in parallel and / or in series.The design of these passages, inlets and outlets is usually defined based on boundary conditions and system requirements.

[0025] According to one aspect of the present disclosure, a gearbox cover is provided in the housing to establish a fluid level of the cooling and / or lubricating fluid in at least one of the compartments for accommodating the electric motor and the gearbox, wherein the fluid level is preferably established based on positioning at least one fluid passage at an elevated position relative to the motor shaft, more preferably relative to a central axis of the motor shaft. Alternatively or additionally, other means for controlling the movement and / or circulation of the cooling and / or lubricating fluid may be provided, for example, in each compartment and / or the fluid pan, such as the provision of bulkheads that can deflect the fluid flow in a predetermined direction and at a predetermined angle.

[0026] Alternatively, the gear cover can be omitted. The level of the cooling and / or lubricating fluid in the first compartment can be determined by the position and location of the bearings or by another passage, such as a drainage port or an opening having a cross-section of approximately 2 mm 2 up to about 200 mm 2 and is used to remove the cooling and / or lubricating fluid from the first and second compartments when the electric drive train is not operating.

[0027] According to one aspect of the present disclosure, the first housing part further comprises at least one common component shared between two further components of the housing, in particular between the two compartments for accommodating the electric motor and the transmission, which preferably has an end plate. The common component is preferably an integral component of one of the two compartments or a standalone component. This further facilitates the space-saving installation of components of the electric drive train into the multi-body housing.

[0028] According to another aspect of the present disclosure, the fluid pan comprises a lateral fluid pan, an axial fluid pan, and a connecting passage enabling fluid communication between the lateral fluid pan and the axial fluid pan. The axial fluid pan may be arranged above the central axis with respect to a direction of gravity. The lateral fluid pan may be arranged at approximately the same distance from the underbody of the vehicle as the central axis, for example, substantially parallel to the central axis. Alternatively, the lateral fluid pan may be arranged in an elevated position relative to the central axis, i.e., laterally of the axial fluid pan at a distance from the underbody of the vehicle that is equal to or less than the distance of the axial fluid pan from the underbody of the vehicle.As an exemplary embodiment, the connecting passage extends at least partially, preferably completely, in the axial direction relative to the central axis of the motor shaft. The use of such a multi-part fluid pan with fluid connection, such as the lateral fluid pan, the axial fluid pan, and the connecting passage, enables space-saving integration of a fluid pan into the multi-body housing. Preferably, one or more fluid pans, such as the lateral fluid pan and the axial fluid pan, are arranged on an upper inner surface of the first compartment with respect to a gravitational direction. Even more preferably, the one or more fluid pans can be fluidically coupled to one another in series and / or parallel by one or more fluid passages of the second housing part.

[0029] According to a further aspect of the present disclosure, the first compartment for accommodating the electric motor may comprise a first circulation chamber and a second circulation chamber opposite the first circulation chamber, wherein the pressure gradient is selected to transfer the cooling and / or lubricating fluid from the first circulation chamber to the second circulation chamber. The pressure gradient is preferably further selected to divert the cooling and / or lubricating fluid from the first compartment into one or more adjacent compartments of the first housing part, such as the second compartment, which are connected to the first compartment via at least one fluid passage of the second housing part. The first and second circulation chambers may be arranged adjacent to the stator or the overhangs of the stator winding and run parallel to the central axis.One or more fluid connections between the first and second circulation chambers can be provided by one or more stator-side fluid passages arranged directly on a surface portion of the stator and / or the overhangs of the stator winding and extending substantially parallel to the central axis. Alternatively or additionally, the at least one stator-side fluid passage can form a through-opening through the stator and / or the overhangs of the stator winding, wherein the through-opening can be arranged substantially parallel to the central axis.

[0030] The cooling and / or lubricating fluid may consist of one or more fluids, such as two, three, four, or five fluids. Examples of cooling and / or lubricating fluids are dielectric fluids such as oil, e.g., mineral oil, and air. A preferred example of a cooling and / or lubricating fluid is a mixture of a dielectric fluid such as oil, e.g., mineral oil, and air. The dielectric fluid and air may be present, at least partially, in separate loops before being mixed, e.g., in a mixing chamber, and separated, e.g., in the fluid sump.

[0031] It is particularly preferred to use a dielectric fluid such as oil and air as the cooling and / or lubricating fluid in order to minimize hydrostatic losses or hydraulic flow resistance, in particular at the gap between the rotor and the stator of the electric motor. The second housing part can provide a second air path for air circulation adjacent to the first air path for oil circulation / evacuation, which is substantially defined by, for example, the fluid pan, the first fluid inlet passage and any fluid passage circulating the oil back to the fluid pan, such as substantially directly via the first fluid outlet passage or via the second fluid outlet passage to the second compartment and a fluid passage fluidly connecting the second compartment and the fluid pan or the first compartment, such as the second fluid outlet passage.The second air path for air circulation may comprise an air inlet and an air outlet provided in the multi-body housing, wherein the air inlet may be connected to an external air pump outside the multi-body housing. The air inlet is fluidly connected to a mixing chamber in which the oil and air are mixed. The mixing chamber is preferably arranged in the fluid path of the first fluid inlet passage such that the oil evacuated from the mixing chamber into the first compartment is mixed with air, thereby forming an oil-air mixture. The pressure gradient distributes the oil-air mixture across the second housing part through the first compartment until the oil-air mixture is collected in the fluid pan, wherein the air can at least partially evaporate from the oil-air mixture and exit the multi-body housing via the air outlet before being recirculated.

[0032] It is particularly preferred that at least the first compartment intended to accommodate the electric motor has an air path for air recirculation in addition to a fluid path for fluid or oil recirculation in order to reduce hydraulic flow resistance. The air can circulate in a closed loop between the first compartment and the fluid pan, wherein the air is separated from the oil-air mixture by gravity and returned / recirculated into the loop. In particular, the air is returned / recirculated to one or more, preferably all, of the mixing chamber, a hollow shaft chamber, the A-side circulation chamber, and the B-side circulation chamber. Alternatively or additionally, components of the transmission can also be supplied with a mixture of oil and air as a cooling and / or lubricating fluid.

[0033] The electric drivetrain may comprise a highly integrated assembly of its components and parts. For this purpose, the multi-body housing may comprise one or all, preferably all, of an electric motor, a transmission, a fluid management module, and an inverter. The electric motor, the transmission, the fluid management module, and the inverter are preferably all integral parts of the electric drivetrain. Alternatively, the electric motor and the transmission may be integral parts of the electric drivetrain, and the fluid management module and the inverter may each be arranged in separate housing parts. A preferred embodiment of the electric drivetrain is a parallel-axis "back-to-back" configuration or a coaxial drivetrain with a differential for effective torque distribution, such as torque vectoring.Alternatively or additionally, the electric motor can be offset or shifted within the drive train, for example with respect to a central axis of the multi-body housing, i.e. designed according to an "off-axis" construction.

[0034] The electric motor can be a permanent magnet synchronous motor (PSM), an externally excited synchronous motor (EESM or SSM), an asynchronous motor (ASM), an induction motor, or any other type of electric motor. The electric motor can be the sole power source or one of the main power sources, such as a BEV. Alternatively, it is possible to use an internal combustion engine (ICE) electric motor in the case of a plug-in hybrid electric vehicle (PHEV).

[0035] The electric motor preferably operates as a wet rotor, with rotating parts such as the impellers and preferably the rotor, as well as corresponding counterparts such as one or more, preferably all, of the stator, the stator windings, and bearings being in direct contact with and exposed to a cooling and / or lubricating fluid. The electric motor, preferably the rotor, has inclined surface sections configured to convey or evacuate a cooling and / or lubricating fluid, such as a mixture of oil and air, when the electric motor is in an energized state. For example, impellers are preferably designed as compensating rings with fins.The inclined surface sections can be positioned on one or more of the motor shaft, on at least one, preferably two, axial end faces of the rotor, a gear hub, a gear or a gear carrier in the form of an open impeller, or a rotating gear assembly as such. The electric motor can comprise, in addition to other components such as those mentioned above, additional parts, including a grounding collar, a temperature sensor, a busbar, a valve, an actuator, etc.

[0036] Further features relating to the design of the first compartment, the electric motor and / or one or more of its components can be found in EP 4 145 677 A1, the contents of which are hereby incorporated by reference in their entirety.

[0037] The transmission may be an epicyclic transmission, i.e., a planetary transmission, a cycloidal transmission, a parallel-axis transmission such as gear, worm, and internal gear transmissions, or any other type of transmission. The transmission may be a single-stage, two-stage, or up to 7-speed dual-clutch transmission or planetary transmission. A preferred example of a transmission is a planetary transmission. For example, transmissions may include a sun gear, a first-stage planet gear, a second-stage planet gear, a ring gear, a planet carrier, a transmission output link, planet carrier grooves, and / or planet carrier blades. The transmission may include one or more additional components, including a clutch, a brake, a valve, an actuator, a parking gear, etc.

[0038] It is preferred that at least some parts or regions of the multi-body housing at least partially spatially separate two or more compartments from each other and / or a compartment from the multi-body housing, such as the end plate of the first compartment, which partially separates the first compartment from the second compartment. This enables a more compact arrangement in the multi-body housing. Alternatively or additionally, components of the electric drive train can be bifunctional and, for example, enable a compact bearing arrangement. For example, the motor shaft of the electric motor can be designed as the sun gear of a planetary gear or transmission. Alternatively or additionally, the fluid pan can be fluidly connected to one or more additional compartments, such as a transmission and / or an inverter, in such a way that the cooling and / or lubricating fluid is discharged from the respective compartment(s) to the fluid pan by the pressure gradient.

[0039] It may be advantageous if additional housing components, such as a third housing component for a fluid management module and / or a fourth housing component for an inverter, are removable from the multi-body housing. This modular design can facilitate maintenance and troubleshooting and enable faster replacement of a defective module.

[0040] A vehicle can, for example, be in the form of a land vehicle, an aircraft, or a watercraft. A land vehicle can, for example, be a road vehicle or a rail-bound vehicle. In particular, a vehicle can be a motor vehicle such as a passenger car, truck, or bus. A preferred vehicle is a passenger car.

[0041] In the present disclosure, the term "central axis" refers to the longitudinal axis defined by the motor shaft of the electric motor. The terms "axial" and "circumferential" refer to directions relative to the central axis. The term "height" is a dimension opposite the direction of gravity. The terms "elevated level," "height," "above," "top," and "upper" refer to a direction opposite the direction of gravity when viewed from a position or plane containing the rotational axis of the motor shaft and perpendicular to the direction of gravity. The term "side" refers to an object, such as the fluid sump, that is at least partially disposed in the plane containing the rotational axis of the motor shaft and perpendicular to the direction of gravity. The term "volume" refers to the total volume of a fluid, such as a cooling and / or lubricating fluid, that can be maximally accommodated in a container or tank.

[0042] The above aspects are for illustrative purposes and are not intended to limit the scope of the invention. Numerous variations of the aspects described above are possible. The various aspects discussed in the present disclosure may be combined in any way to produce additional advantages. Furthermore, some of the features may form the basis for one or more divisional applications.

[0043] The invention is explained below by way of examples using the embodiments shown in the figures. They show:

[0044] Figure 1 is a schematic view of a vehicle with the electric drive train and a battery;

[0045] Figure 2 is a perspective view of a multi-body housing for an electric drive train; Figure 3 is a further perspective view of the multi-body housing for an electric drive train of Figure 2;

[0046] Figure 4 is a rear view of the multi-body housing for the electric drive train of Figure 2;

[0047] Figure 5 is a sectional view of the multi-body housing for the electric drive train along the section plane AA of Fig. 4;

[0048] Figure 6 is a sectional view of the multi-body housing for the electric drive train along the section plane BB of Fig. 4;

[0049] Figure 7 is a semi-transparent side view of the multi-body housing for the electric powertrain of Figure 3;

[0050] Figure 8 is a sectional view of the multi-body housing for the electric drive train along the section plane CC of Fig. 7;

[0051] Figure 9 is a sectional view of the multi-body housing for the electric drive train along the section plane DD of Fig. 7;

[0052] Figure 10 is a sectional view of the multi-body housing for the electric drive train along the section plane EE of Fig. 7; and

[0053] Figure 11 is a sectional view of the multi-body housing for the electric drive train along the section plane FF of Fig. 7

[0054] The same objects, functional units, and comparable components are provided with the same reference numbers in the figures. These objects, functional units, and comparable components are identical in terms of their technical features, unless the description explicitly or implicitly discloses otherwise.

[0055] Fig. 1 shows a schematic view of a vehicle 300. The vehicle 300 includes an electric drivetrain 200 according to the present invention, which is connected to a secondary battery 250. The vehicle 300 is an at least partially electrified vehicle, such as a fully electric vehicle (EV) or a hybrid electric vehicle (HEV). The battery 250 can be a lithium-ion battery, a lithium iron phosphate battery, or a fuel cell battery. The electric drivetrain 200 is supplied with a DC voltage from the battery 250, which is converted into an AC voltage. This is done by means of an inverter 4 (see Figs. 2 and 3) of the electric drivetrain 200.

[0056] 2 and 3 show schematic perspectives of an exemplary multi-body housing 11 for the electric drive train 200. In the exemplary embodiment shown, the multi-body housing 11 comprises a first housing part for receiving parts of the electric drive train 200, in particular an electric motor 1 and a transmission 2. For this purpose, the first housing part is designed such that it forms one or more compartments 10, 75, each for receiving one of the components of the electric drive train 200. In addition, the multi-body housing 11 comprises a second housing part for discharging a cooling and / or lubricating fluid (e.g., oil or a mixture of oil and air) from the one or more compartments 10, 75 to a fluid pan 76, 77, which is shown in detail in Fig. 6.For this purpose, the second housing part is designed to form a plurality of fluid passages that fluidically couple the one or more compartments 10, 75 to the fluid pan 76, 77. The removal of the cooling and / or lubricating fluid is enabled by means of a pressure gradient along at least one of the plurality of fluid passages. The pressure gradient is generated by the rotation of a motor shaft 55 and / or by the rotation of a counterpart of the motor shaft 55, such as an impeller 54, when the electric motor 1 is switched on. It is conceivable that additional housing parts are formed, wherein each of the additional housing parts comprises at least one compartment 10, 75.

[0057] Furthermore, a fluid management module 3 and a further housing part for accommodating the inverter 4 are mounted on the multi-body housing 11, as shown by way of example in Figs. 2 and 3. However, this is not limiting for the present invention, since such a further housing part can alternatively be mounted within the multi-body housing 11 (not shown here). The fluid management module 3, which is designed to enable the flow control of an oil as a cooling and / or lubricating fluid in the present embodiment, comprises an oil filter, an oil cooling system, and a heat exchanger (all not shown) configured to remove heat from a cooling and / or lubricating fluid flowing through it, such as a dielectric fluid, in particular oil.The fluid management module 3 further comprises additional components such as an oil pump, an oil pump connection, and an oil pump intake pipe, the function of which is explained below. Furthermore, based on the DC voltage provided by the battery 250, a direct current can be generated and supplied to the inverter 4 of the electric drive train 200. The inverter 4 is configured to convert the direct current provided by the battery 250 into an alternating current required to operate the electric motor 1, which is housed in a first compartment of the multi-body housing 11. The gearbox 2 is essentially a rotating circular machine part with gears connected to the motor shaft 55 and serving to change one or more of the torque, axis of rotation, and rotational speed transmitted by the electric motor 1.

[0058] With further reference to Fig. 4, a side view of the multi-body housing 11 for the electric drive train 200 is shown with definitions for the section planes AA and BB, and in Fig. 7, a rear view of the multi-body housing 11 for the electric drive train 200 is shown with definitions for the section planes CC, DD, EE and FF. With reference to the section planes AA and BB, as shown by way of example and schematically in Figs. 5 and 6, the first housing part comprises a first compartment 10 for receiving the electric motor 1. The electric motor 1 comprises the motor shaft 55, which extends along a central axis CA. The motor shaft 55 is provided with a rotor 53, which is provided with impellers 54 at the opposite axial ends.The rotation of the motor shaft 55 is driven by the stator 51 with stator windings 52 and winding overhangs 521, 522 extending over the rotor 53 to generate the required rotating magnetic field that sets the rotor 53 in rotation about the central axis CA. The first housing part comprises a common end plate 111 that is adjacent to the B-side winding overhang 521 of the electric motor 1 and divides the first housing part into the first compartment 10 with the electric motor 1 arranged therein and the second compartment 75 with the gearbox 2. As can be seen from Fig. 5, the common end plate 111 is oriented substantially parallel to the rear of the multi-body housing 11. The first housing part may further comprise an end plate 12 and a cover 13 adjacent to the rear of the multi-body housing 11, such that the first compartment 10 is arranged substantially between the end plate 12, a cover 13 and the common end plate 111.Accordingly, the components of the transmission 2 are arranged between a transmission housing 14, a transmission cover 15, and the common end plate 111. It should be noted that the end plate 12, the cover 13, the transmission housing 14, and / or the transmission cover 15 can also be designed as one side of the multi-body housing 11 or can be partially omitted. These optional components enable the formation of fluid passages and / or partition walls for guiding the cooling and / or lubricating fluid within the multi-body housing 11.

[0059] The transmission 2 is arranged in the second compartment 75, as shown by way of example in FIGS. 5 and 6, and comprises a sun gear 552, a first planetary gear 61, a second planetary gear 611, and a ring gear 62 as a gear set, which operates in a known manner to change the speed and / or direction of rotation of the motor shaft 55 and which is arranged in a gear chamber 75. The transmission 2 further comprises a planetary carrier 63, a transmission output port 631, carrier grooves 633, and carrier blades 634 as additional components. The components of the transmission 2 are arranged between the optional transmission housing 14, the transmission cover 15, and the common end plate 111.

[0060] The multi-body housing 11 further comprises a fluid pan 76, 77 in the form of an axial fluid pan 76 and a lateral fluid pan 77. In the present exemplary embodiment, the fluid pan 76, 77 contains oil as a cooling and / or lubricating fluid. The axial fluid pan 76 and the lateral fluid pan 77 are both located on an upper circumferential side of the electric motor 1 with respect to a gravitational direction, as can be seen in detail in Fig. 6.

[0061] The fluid pan 76, 77 is in fluid communication with the plurality of fluid passages of the second housing part of the multi-body housing 11, wherein the plurality of fluid passages are adapted so that the cooling and / or lubricating fluid can flow through. In particular, the cooling and / or lubricating fluid enters the first compartment 10 via an oil-air mixing chamber 71, which can function as a first fluid inlet passage, and enters the first compartment 10 in a hollow shaft chamber 72, which surrounds the motor shaft 55, at an elevated position relative to the motor shaft 55. Consequently, the first compartment 10 is filled with the cooling and / or lubricating fluid even when the electric motor 1 is inactive. The electric motor 1 is thus supplied with the cooling and / or lubricating fluid under the effect of gravity on the cooling and / or lubricating fluid in order to achieve sufficient functionality upon restarting.

[0062] When the electric motor 1 drives the rotor 53, the impellers 54 discharge the cooling and / or lubricating fluid toward the central axis CA, and the cooling and / or lubricating fluid is accelerated by centrifugal force and released from the hollow shaft chamber 72 through shaft outlets 551. The pressure difference created by the impeller 54 forces the cooling and / or lubricating fluid into a B-side circulation chamber 72 located in the region of the B-side winding overhang 521 of the stator 51. An A-side circulation chamber 74 is further located near the A-side winding overhang 522 of the stator 51. A B-side circulation chamber 73 is located in the region of the B-side winding overhang 521 of the stator 51.The A-side circulation chambers 74 are connected by fluid passages (not shown) of the second housing part, which are arranged within the stator 51 and oriented substantially parallel to the central axis CA, and by an air gap 511 between the stator 51 and the rotor 53. Driven impellers 54 pump the cooling and / or lubricating fluid from the B-side circulation chamber 73 through the fluid passages into the A-side circulation chamber 74, wherein the cooling and / or lubricating fluid circulates in the B-side circulation chamber 73 and the A-side circulation chamber 74 to dissipate the heat generated from the electric motor 1 and in particular the A-side and B-side winding overhangs 521, 522 of the stator 51.

[0063] Furthermore, the common end plate 111 separating the first compartment 10 from the second compartment 75 includes a curved surface conforming to the shape of the impeller 54. This promotes proper circulation of the cooling and / or lubricating fluid and its deflection through baffles or oil traps into the bearing lubrication areas (not shown).

[0064] The cooling and / or lubricating fluid may be evacuated to one or more of the fluid pans 76, 77, another compartment 10, 75, such as the second compartment 75 housing the transmission, and / or another housing portion defining another compartment for receiving additional components of the electric powertrain 200, after the cooling and / or lubricating fluid has been evacuated from the B-side circulation chamber 73 into the A-side circulation chamber 74 by the pressure differential created by the impellers 54 and new cooling and / or lubricating fluid has been introduced into the first compartment 10 by a combination of the hydrostatic pressure exerted by the higher fluid pan 76, 77 and the suction force provided by the impellers 54.In the embodiment shown, a first portion of the cooling and / or lubricating fluid is discharged to the fluid pan 76, 77, and a second portion of the cooling and / or lubricating fluid is discharged to the gearbox 2, which is arranged in the second compartment 75 of the first housing part. For this purpose, the first compartment 10 has raised first fluid outlet passages 81, 82, 83, wherein an axially extending first raised fluid outlet passage 81 corresponds to the second fluid inlet passage, a radially extending first raised fluid outlet passage 82 corresponds to the second fluid inlet passage, and a radially extending second raised fluid outlet passage 83 corresponds to the first fluid outlet passage.The raised first fluid outlet passages 81, 82, 83 are thus divided into the first raised axial fluid outlet passage 81, which runs parallel to the central axis CA to transfer the second part of the cooling and / or lubricating fluid led from the A-side circulation chamber 74 to the second compartment 75, the first raised radial fluid outlet passage 82 to transfer the first part of the cooling and / or lubricating fluid led from the A-side circulation chamber 74 to the fluid pan 77, and the second raised radial fluid outlet passage 83, which runs perpendicular to the central axis CA to distribute the cooling and / or lubricating fluid in the multi-body housing 11 from the second compartment 75 to the fluid pan 76, 77.In the fluid pan 76, 77, the oil of the cooling and / or lubricating fluid can be partially separated from dissolved air and then repeat the cycle by being evacuated to the mixing chamber 71 to contact and mix with air before being returned to the hollow shaft chamber 72.

[0065] As already mentioned, the cooling and / or lubricating fluid leaving the first compartment is divided at the raised axial fluid outlet passages 81, 82 to evacuate the electric motor 1 with a higher flow rate and the gearbox 2 with a lower flow rate of the cooling and / or lubricating fluid. In this case, the flow rate to the electric motor 1 is approximately 10 l / min and to the gearbox approximately 2 l / min, which ensures sufficient cooling for both components, although the electric motor 1 requires more intensive cooling than the gearbox. Openings (not shown) with different cross-sectional areas can be provided to the raised axial fluid outlet passages 81, 82 to discharge the cooling and / or lubricating fluid at the predetermined flow rates.

[0066] Returning to the second compartment 75, which houses the transmission 2, the cooling and / or lubricating fluid flows through the first raised axial fluid outlet passage 81, which has an opening provided with an oil deflector 811 to change the direction of the fluid flow. The cooling and / or lubricating fluid enters the second compartment 75 at the transmission lubrication port 632 before flowing through / cooling and lubricating the components of the transmission 2, in particular the sun gear 552, the first planetary gear 61, the second planetary gear 611, and the ring gear 62. A cooling and / or lubricating fluid flow deflector 112 can be arranged in the second compartment 75 to ensure the flow of the cooling and / or lubricating fluid in a predetermined direction and at a predetermined angle. The cooling and / or lubricating fluid leaves the second compartment 75 via the oil channel 141 and thereby reaches the fluid pan 76, 77.

[0067] It should be noted that the rotation of at least one component of the gearbox 2, which is arranged in a force-locking manner and thus driven by the electric motor 1, can be used to promote the flow of the cooling and / or lubricating fluid in the gearbox chamber 75 and to discharge the cooling and / or lubricating fluid from the gearbox chamber 75 to the lateral fluid pan 77 via at least one second elevated radial fluid outlet passage 83. In this case, however, the required pressure gradient across the multi-body casing is provided by the impellers 54.

[0068] In the example shown, the fluid level of the cooling and / or lubricating fluid in the second compartment 75 and the fluid level of the cooling and / or lubricating fluid in the first compartment 10 depend in part on the use of the gear cover 15, which is defined by the location of the first raised radial fluid outlet passage 82. In an alternative embodiment, in which no external gear cover 15 is present, but only the fluid pan 77 is arranged between the first compartment and the adjacent lateral oil pan 76, the fluid level of the cooling and / or lubricating fluid in the second compartment 75 and the fluid level of the cooling and / or lubricating fluid in the first compartment 10 are determined either by the position and location of the bearings or by another fluid passage, such as a drainage port or an opening with a cross-section of approximately 2 mm 2 up to about 200 mm 2, which is used to remove the cooling and / or lubricating fluid from the first and second compartments 10, 75 when the electric drive train 200 is not operating.

[0069] The cross-section along section plane CC in Fig. 8, section plane DD in Fig. 9, and section plane EE in Fig. 10 show additional details of the cooling and / or lubricating fluid circuit in the multi-body housing 11 purely schematically and by way of example. Oil as the cooling and / or lubricating fluid is injected into the multi-body housing 11 via the fluid management module 3. For this purpose, the fluid management module 3 has an oil pump port 803, an oil pump 804 and an oil suction manifold 805 for receiving oil from outside the multi-body housing 11. At the junction between the fluid management module 3 and the multi-body housing 11, the oil enters the second housing part through an oil pressure port 32 and is then distributed within the second housing part via an axial oil supply passage 773 which is in fluid communication with an oil supply connection chamber 776, where it is released or directed into the mixing chamber 71.In addition, air is supplied to the mixing chamber 71 via an axial air circulation passage 774, which communicates with an air circulation connection passage 775. As already mentioned, the oil in the mixing chamber 71 then circulates into the hollow shaft chamber 72, where the oil is mixed with air and guided by centrifugal force to the shaft openings 551. As can also be seen, phase terminals 523 for electrically connecting the electric motor 1 to the inverter 4 are arranged adjacent to the axial oil supply passage 773 and the oil supply connection chamber 776 to enable cooling of the phase terminals 523.

[0070] As also evident from Fig. 9, the second housing part in the illustrated embodiment comprises four axial connecting passages 84, which are evenly distributed around the central axis CA and are in fluid communication with the first elevated passage in the radial direction 82 and the fluid trough 76, 77. One of the axial connecting passages 84, which is located in an elevated position relative to the central axis CA, fluidically connects the fluid trough 76 to the fluid trough 77. Outer peripheries of the axial connecting passages 84 form connecting walls 771 for guiding the fluid flow within the multi-body housing 11.

[0071] The fluid flow is shown in a section of the multi-body housing 11 beyond the second raised radial fluid outlet passage 83, as viewed from the central axis CA, with reference to the cross-section along the section plane EE in Fig. 10 and the section plane FF in Fig. 11. It should be noted that the dimensions of this section may vary depending on the specific requirements, such as the dimensions of the fluid pan 76, 77, since the components of the electric motor 1 and the transmission 2 are arranged substantially within the perimeter defined by the second raised radial fluid outlet passage 83. This enables the multi-body housing 11 to be installed into the electric powertrain 200 in a compact and space-saving manner.In particular, the fluid pan 76, 77 can be arranged in the section, preferably the upper section, beyond the circumference defined by the second raised radial fluid outlet passage 83, but still within the multi-body housing 11, e.g., cubically, i.e., as an integral part thereof. In particular, the axial air circulation passage 774 and the axial oil supply passage 773 for circulating the cooling and / or lubricating fluid to the second compartment 75 are shown. The axial oil supply passage 773 is in fluid communication with the oil pressure port 32, which fluidly connects the first housing part to the fluid management module 3. Connecting walls 771 are formed and positioned in the multi-body housing 11 in a meandering structure to prevent the cooling and / or lubricating fluid from accumulating on one side of the fluid pan 77.In addition, supporting or connecting ridges of the first housing part function as a boundary wall 772, which delimits the cavity of the first housing part into separate sections used for cooling and / or lubricating fluid return. This makes it possible to eliminate additional pipes within the first housing part, so that the space provided by the first compartment 10 for accommodating the electric motor 1 and the space between the first housing part and the multi-body housing 11 is used for the closed cooling and / or lubricating fluid circuit. An intake port 31 of an oil pump (not shown) is located at a level below the central axis CA, which forms the bottom of the fluid pan 77, where the oil is collected and returned to the first compartment 10. In the embodiment shown in Fig.In the exemplary embodiment shown in Figure 10, the fluid pan 76, 77 is arranged on an outer side of the multi-body housing 11, facing away from the fluid management module 3. However, this is not limiting for the present invention, since the fluid pan 76, 77 can be arranged at least partially, preferably completely, on an inner side of the multi-body housing 11, facing the fluid management module 3. This enables a reduction in the overall size of the multi-body housing 11 on its outer side, thus achieving an even more compact electric drive train 200.

[0072] List of reference symbols:

[0073] electric motor

[0074] Gearbox

[0075] Fluid management module

[0076] Inverter (Inverter) first compartment (first compartment)

[0077] Multibody housing

[0078] End plate

[0079] cover

[0080] Gearbox housing

[0081] Gearbox cover

[0082] Intake port

[0083] Print port

[0084] Stator (or stator core)

[0085] Stator windings

[0086] Rotor (or rotor core)

[0087] balance bike

[0088] Motor shaft first planetary gear

[0089] Ring gear

[0090] planet carrier

[0091] Mixing chamber hollow wave chamber

[0092] B-side circulation chamber

[0093] A-side circulation chamber second compartment (second receiving compartment) axial fluid pan lateral fluid pan first raised axial fluid passage (first raised axial fluid outlet passage) first raised radial fluid passage (first raised radial fluid outlet passage) second raised radial fluid passage (second raised radial fluid outlet passage)

[0094] Axial connecting passages split end plate

[0095] Cooling and / or lubricating fluid flow control

[0096] Oil channel electric powertrain

[0097] secondary battery

[0098] vehicle

[0099] air gap

[0100] B-side winding overhang

[0101] A-side winding overhang

[0102] Phase connections

[0103] sun gear

[0104] Shaft outlets second planetary gear

[0105] Gearbox output connection

[0106] Gearbox lubrication opening

[0107] Carrier grooves

[0108] Carrier sheets

[0109] Connecting walls

[0110] Axial oil supply passage

[0111] Axial air circulation passage

[0112] Air circulation connecting passage

[0113] Oil supply connection chamber

[0114] Air intake

[0115] Air outlet

[0116] Oil pump connection

[0117] oil pump

[0118] Oil intake manifold 811 oil deflector

[0119] CA central axis

Claims

Claims 1 . Multi-body housing (11) for an electric drive train (200), comprising - a first housing part which forms one or more compartments (10, 75) for receiving components of the electric drive train (200), wherein the one or more compartments (10, 75) comprise or comprise a first compartment (10) for receiving a first component in the form of an electric motor (1) with a motor shaft (55), and - a second housing part forming a plurality of fluid passages for conducting a cooling and / or lubricating fluid, wherein the second housing part is designed to evacuate the cooling and / or lubricating fluid from the one compartment or the plurality of compartments (10, 75) by means of a pressure gradient along at least one of the plurality of fluid passages, wherein the pressure gradient is generated by means of rotation of the motor shaft (55) and / or by means of rotation of a counterpart of the motor shaft (55) when the electric motor (1) is in a switched-on state, wherein the housing (11) comprises, as an integral component, a fluid trough (76, 77) for receiving the cooling and / or lubricating fluid from the plurality of fluid passages, wherein the first compartment (10) is fluidically coupled to the fluid trough (76, 77) via at least one of the plurality of fluid passages.

2. Housing (11) according to claim 1, wherein the fluid pan (76, 77) is arranged on an outer side of the electric motor (1) and / or on an outer side of the first compartment (10), preferably wherein the fluid pan (76, 77) is arranged on a left outer side or a right outer side of the electric motor (1) and / or on a left outer side or a right outer side of the first compartment (10).

3. Housing (11) according to one of claims 1 to 2, wherein the fluid tray (76, 77) is at least partially located on an upper outer side of the electric motor (1). with respect to a direction of gravity and / or at least partially on an upper outer side of the first compartment (10) with respect to the direction of gravity.

4. Housing (11) according to claim 3, wherein the fluid tray (76, 77) has a volume, wherein at least 10% of the volume is located on the upper outer side of the electric motor (1) with respect to the direction of gravity and / or on the upper outer side of the first compartment (10) with respect to the direction of gravity.

5. Housing (11) according to one of claims 1 to 4, wherein the plurality of fluid passages comprises a first fluid inlet passage for providing the cooling and / or lubricating fluid from the fluid pan (76, 77) to the first compartment (10), wherein the first fluid inlet passage is arranged at an elevated position relative to the motor shaft (55), preferably relative to a central axis of the motor shaft (55).

6. Housing (11) according to one of claims 1 to 5, wherein the plurality of fluid passages comprises a first outlet fluid passage for providing the cooling and / or lubricating fluid from the first compartment (10) to the fluid pan (76, 77), wherein the first outlet fluid passage is arranged at an elevated position relative to the motor shaft (55), preferably relative to a central axis of the motor shaft (55).

7. Housing (11) according to one of claims 1 to 6, wherein the first housing part comprises a second compartment (75) for receiving a second component, preferably designed as a gear (2), wherein the second compartment (75) is fluidically coupled to the fluid trough (76, 77) via at least one of the plurality of fluid passages.

8. Housing (11) according to claim 7, wherein the second compartment (75) is fluidly coupled to the first compartment (10) via a second outlet fluid passage, preferably wherein the second outlet fluid passage is arranged at an elevated position relative to the motor shaft (55), more preferably relative to a central axis of the motor shaft (55).

9. Housing (11) according to claim 8, wherein a cross-sectional size ratio, in particular a diameter ratio, between a first cross section of the first fluid outlet passage and a second cross section of the second fluid inlet passage is selected to be proportional to a flow ratio between a first flow rate of the cooling and / or lubricating fluid for the electric motor (1) and a second flow rate of the cooling and / or lubricating fluid for the transmission (2).

10. Housing (11) according to one of claims 1 to 9, wherein the cooling and / or lubricating fluid comprises a mixture of oil and air, the fluid pan (76, 77) is designed as an oil pan and the second housing part has a mixing chamber (71) for providing the mixture of oil and air, wherein the plurality of fluid passages comprise a second fluid inlet passage for providing oil from the oil pan to the first compartment (10) via the mixing chamber, wherein the mixing chamber (71) has an air inlet passage for guiding air to the mixing chamber (71).

11. Housing (11) according to one of claims 1 to 10, wherein the pressure gradient is adapted to evacuate a first part of the cooling and / or lubricating fluid guided from the first compartment (10), in particular from a circulation chamber formed in the first compartment (10), to the second compartment (75) serving to accommodate a gear (2) via a first fluid passage extending in the axial direction with respect to the motor shaft (55), and / or to evacuate a second part of the cooling and / or lubricating fluid guided from the first compartment (10), in particular from the circulation chamber, to the fluid pan (76, 77). to be evacuated via a second fluid passage extending in the axial direction with respect to the motor shaft (55).

12. Housing (11) according to one of claims 1 to 11, wherein a gear cover is provided in the housing (11) in order to establish a fluid level of the cooling and / or lubricating fluid in at least one of the compartments (10, 75) for accommodating the electric motor (1) and a gear (2), wherein the establishment of the fluid level is preferably based on positioning at least one fluid passage at an elevated position relative to the motor shaft (55), more preferably relative to a central axis of the motor shaft (55).

13. Housing (11) according to one of claims 1 to 12, wherein the housing (11) further comprises at least one common component shared between two further components of the housing (11), in particular between the two compartments (10, 75) for accommodating the electric motor (1) and the gearbox (2), which common component preferably has an end plate (111), wherein the common component is preferably an integral component of one of the two compartments (10, 75) or an independent component.

14. Electric drive train (200) for an at least partially electrified vehicle (300), comprising: - an electric motor (1 ); - a multi-body housing (11) according to one of claims 1 to 13.

15. At least partially electrified vehicle (300) comprising an electric drive train (200) according to claim 14.

Images