Housing assembly and electric drive having such housing assembly

Abstract

The invention relates to a housing assembly for an electric drive, comprising a motor housing part (3) having a jacket part (6) and a first gear housing part (7) integrally formed therewith, a housing (4) mountable to the jacket part (6), an inverter housing part (5) having an inverter housing part (13) and a second gear housing part (14) integrally formed therewith, wherein the inverter housing part (13) is arranged axially adjacent to the second gear housing part (14), the second gear housing part (14) comprises a gearbox cooling channel (22) fluidly connected to a cooling chamber (17) of the inverter housing part (5), the motor housing part (3) and the inverter housing part (5) can be connected to each other by means of a connecting element, and wherein, in the mounted condition, the motor housing part (3) and the inverter housing part (5) are connected to each other by means of a connecting element. A closed cooling circuit is formed from the fluid connector (16) of the inverter housing part (5) via the cooling chamber (17) and the gearbox cooling channel (22) to the motor cooling channel (8) of the motor housing part (5).

Description

Technical Field

[0001] The invention relates to a housing assembly for an electric drive device for driving a motor vehicle. In addition, the invention relates to an electric drive device having such a housing assembly. Background Art

[0002] From US 2021 394 600 A1, an electric drive device is known, which comprises a housing assembly, an electric motor with a hollow shaft, a planetary gearing and a differential gearing. The housing assembly comprises a first housing part on the motor side, a second housing part on the gearing side and an intermediate housing part arranged therebetween. The intermediate housing part comprises an integrally formed intermediate wall, a motor-side jacket part and a gearing-side jacket part. A sealed chamber for a coolant to flow through is formed between the outer surface of the motor-side jacket part and the inner surface of the first gearing part.

[0003] A drive unit is known from WO 2019 182 622A1, which includes an electric motor and a first circulation channel for a first coolant for cooling the electric motor, and a second circulation channel for a second coolant separated therefrom. The second circulation channel has a heat exchange portion with the circulation channel for the first coolant. The drive unit is provided with an inverter for controlling the motor. The circulation channel for the second coolant has a cooling portion for cooling the inverter. The inverter includes a power module with a switching transistor for converting direct current from a battery power source into three-phase alternating current for the electric motor.

[0004] A motor-integrated inverter is known from US 2 022 190 764 A1. The inverter includes a motor having an axis arranged in a horizontal direction, and a power module configured to generate driving power for driving the motor and coupled to the motor in the direction in which the axis is arranged.

[0005] A power generation module is known from US2022006349 A1, comprising: an electric motor including a motor housing; an inverter, which is arranged on a first side of the motor housing and includes an inverter housing, which is configured to accommodate an insulated gate bipolar transistor (IGBT) and a capacitor; an inner housing, which is arranged in the motor housing and is configured to accommodate a stator and a rotor. A dual flow path is arranged on the circumferential surface of the motor housing. A similar module is known from US2022 006350A1.

[0006] An electric drive device having a power electronics unit and an electrical connector is known from DE 10 2020 207 101 A1. The power electronics unit is arranged on top of a housing, thereby forming a T-shaped structure.

[0007] DE 10 2015 219 669 A1 discloses an electric machine having a stator, a rotor and a power electronics unit for controlling the stator. The power electronics unit is arranged axially in front of or behind the stator relative to the motor axis. Summary of the invention

[0008] In addition to the functionality and efficiency of the power electronics, space requirements and weight are also important criteria in development. In order for electric and hybrid vehicles to operate at a particularly high efficiency level, it is necessary not only to keep the temperature of the electric motor and battery within the efficiency-optimized temperature range, but also the temperature of the power electronics. To ensure this, a powerful thermal management system is required that cools the components accordingly and keeps them within the optimal temperature window.

[0009] The invention is based on the object of proposing a housing assembly for an electric drive of a motor vehicle, which ensures reliable cooling of the components of the electric drive and has a compact design. The invention is also aimed at providing a corresponding electric drive for a motor vehicle, which has high efficiency and good cooling properties and a compact design.

[0010] According to the present invention, a housing assembly for an electric drive device for driving a motor vehicle is proposed to solve the object, the housing assembly comprising: a motor housing portion having a jacket portion for accommodating a stator of an electric motor and a first gear housing portion for accommodating a portion of a gear device, wherein the jacket portion and the first gear housing portion are formed integrally; an outer jacket portion that can be mounted to the jacket portion, wherein in the mounted state, the outer jacket portion and the jacket portion are arranged coaxially with respect to the motor axis and include a motor cooling channel through which a cooling fluid can flow to cool the electric motor; an inverter housing portion having an inverter housing portion for accommodating an inverter of the electric motor and a second gear housing portion formed integrally with the inverter housing portion, wherein the inverter housing portion is arranged axially adjacent to the second gear housing portion and includes a fluid connector that is fluidly connected to a cooling chamber in the inverter housing portion, wherein the second gear housing portion includes a gearbox cooling channel that is fluidly connected to the cooling chamber; wherein the first gear housing portion and the second gear housing portion can be mechanically connected to each other by a connecting element; wherein in the connected state, a closed cooling circuit is formed from the fluid connector of the inverter housing portion via the cooling chamber and the gearbox cooling channel to the motor cooling channel.

[0011] An advantage of the proposed housing assembly is that it has a compact design, which can have a substantially cylindrical shape relative to the motor axis. The housing volume can be concentrated at the same height or radial distance, avoiding inconsistencies in the radial direction. Thus, a good packaging is achieved and the housing assembly allows the number of housing parts to be reduced to only three, for example two tanks and one cover. For example, the first and inverter housing parts and / or the outer jacket part can be cast from a light metal, such as aluminum or an aluminum alloy. In an exemplary embodiment, the assembly can be configured as a two tank and three cover housing assembly, wherein the motor and inverter housing parts form the two tanks, and the casing and two optional additional covers of the inverter housing part form the three covers.

[0012] In a preferred embodiment, the inverter housing part forms an axial end of the housing assembly relative to the motor axis. The inverter housing part may be open in the axial direction so that the inverter can be axially mounted. A cover may be provided to close the inverter housing part.

[0013] The motor housing portion forms half of the housing of the motor and the housing of the gear arrangement. The inverter housing portion forms the other half of the housing of the inverter and the housing of the gear arrangement. The motor and inverter housing portions are connected to each other by means of their gear arrangement housing portions. To this end, the first and second gear housing portions may include circumferentially distributed connecting elements, such as flanges and / or bolts, by means of which they can be mechanically connected to each other. In the assembled state, the two halves of the gear arrangement housing jointly form an inner chamber in which the gear arrangement is accommodated. The cooling structure of the inverter housing portion is fluidly connected to the cooling structure of the motor housing portion. In the assembled state, the two cooling structures form part of a closed cooling circuit, through which a cooling fluid flows during operation of the assembly. Therefore, the cooling fluid flows through the inverter housing portion to cool the inverter and a part of the gear arrangement, and flows through the motor housing portion to cool the motor.

[0014] The closed cooling system is arranged in the wall of the housing and is not in contact with the inner chamber of the housing assembly. Thus, the gear arrangement arranged in the gearbox housing can be cooled and lubricated by a second fluid different from the cooling fluid of the housing assembly. The cooling fluid can be water or a water-based coolant, such as ethylene glycol. For example, the fluid used to lubricate the gear arrangement can be oil. The motor can be cooled and lubricated with the same fluid as the gear arrangement. However, in the case of a dry motor, it can also be lubricant-free.

[0015] According to one embodiment, the first gear housing portion may include a first through hole for the first output shaft, and the second gear housing portion may include a second through hole for the second output shaft. The first and second shaft openings may be arranged so that the opening axis extends parallel to the motor axis. The gearbox cooling channel of the inverter housing portion may have a C-shape in a cross-sectional view. The C-shaped gearbox cooling channel may extend at least 180° relative to the axis circumference of the through hole of at least one of the first and second gear housing portions.

[0016] The inverter housing part may have an intermediate cooling channel, which may be arranged between the inverter cooling chamber and the gearbox cooling channel. Thus, the cooling fluid may flow from the inverter cooling chamber through the intermediate cooling channel to the gearbox cooling channel. With the intermediate cooling chamber, a larger part of the inverter housing part is cooled. The intermediate cooling channel may have a C-shape in a cross-sectional view. The intermediate cooling channel may be arranged to deviate axially and / or radially from the gearbox cooling channel. In particular, the intermediate cooling channel may be arranged to extend in a circumferential direction around the motor axis, for example extending by at least 180°.

[0017] A first connecting channel may be formed between the motor housing portion and the inverter housing portion to fluidly connect the cooling structure of the motor housing portion with the cooling structure of the inverter housing portion. A return path may be arranged between an outlet connector of the motor channel and an inlet connector of the inverter housing portion. A heat exchanger may be arranged in the return path to cool the cooling fluid that has absorbed heat when flowing from the gear arrangement and the motor through the housing. The first connecting channel may be formed from an end section of the gearbox cooling channel to an inlet section of the motor cooling channel.

[0018] According to a first embodiment, there is only one connecting channel between the motor housing part and the inverter housing part, so that the cooling fluid flows through them in series, first through the cooling structure of the inverter housing part and then through the cooling structure of the motor housing part.

[0019] According to another embodiment, a second connecting channel can be formed between the motor housing part and the inverter housing part. In this case, the cooling fluid flows functionally in parallel, wherein the first coolant flow flows from the inverter cooling chamber indirectly to the motor housing part via the gearbox channel, and the second coolant flow bypasses the gearbox channel and flows directly to the motor housing part. During operation of the electric drive device, the motor generates more heat. Therefore, the cooling structure of the inverter housing part is preferably formed so that at least 30%, in particular more than 40%, of the coolant flowing into the inverter housing part flows directly to the motor cooling channel through the second connecting channel, wherein the remaining coolant flows indirectly to the motor cooling channel through the gearbox cooling channel.

[0020] According to a specification, the second connecting channel can connect the intermediate cooling channel of the inverter housing part with the second inlet of the motor cooling channel. According to an alternative specification, the second connecting channel can connect the cooling chamber of the inverter housing part with the second inlet of the motor cooling channel.

[0021] Furthermore, with regard to the above-mentioned object, an electric drive device for driving a motor vehicle is proposed, comprising: a housing assembly, which can be configured according to any of the above-mentioned embodiments; an electric machine, comprising a stator and a rotor, wherein the stator is connected to a jacket portion of a motor housing portion in a rotationally fixed manner, wherein the rotor is drivingly connected to a rotor shaft, which is rotatably supported in the housing assembly around a motor axis; a gear arrangement that transmits the rotational movement of the rotor shaft to a first output shaft and a second output shaft of a gearbox; and an inverter arranged in an inverter housing portion of an inverter housing portion. The stator can be axially connected to the motor housing portion, in particular so as to be axially supported to the motor housing portion.

[0022] The electric drive has the same advantages as described with respect to the housing assembly, so reference is made here to the above description.

[0023] The inverter, which can also be called power electronics, is functionally located between the battery and the motor of an electric vehicle. The inverter controls and monitors the motor and ensures that the torque supply and speed control of the powertrain meet the requirements. When the motor is operating in motor mode, the inverter supplies power from the battery to the motor. When the motor is operating in generator mode, the inverter feeds power to the battery. In this process, called energy recovery, the inverter converts the alternating current (AC) generated by the motor into direct current (DC), thereby charging the battery. In motor mode, the inverter converts the DC voltage of the battery into the AC voltage required by the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The preferred embodiments of the present invention are described below using the accompanying drawings. Figure 1A The housing assembly in a first embodiment according to the present invention is shown in a 3D exploded view; Figure 1B The 3D view shows the installed state Figure 1A A housing assembly (without a cover); Figure 1C Based on Figure 1B The 3D view shows Figure 1A and 1B A cooling structure of a housing assembly; Figure 1D The axial view shows Figure 1A A housing assembly; Figure 1E Based on Figure 1DAn axial view of the cooling structure of the housing assembly is shown; Figure 1F Based on Figure 1D The longitudinal section of section 1F-1F shows the inverter housing portion; Figure 1G Shown in top view Figure 1A A housing assembly; Figure 1H Based on Figure 1G A top view of the cooling structure of the housing assembly is shown; Figure 1J Based on Figure 1G The cross section along section line 1J-1J shows Figure 1A A housing assembly; Figure 1K The connection between the inverter cooling channel and the motor cooling channel is shown; Figure 2A The housing assembly according to the second embodiment of the present invention is shown in a 3D view; Figure 2B Shown in 3D view Figure 2A A cooling structure of a housing assembly; Figure 2C The cooling structure of the housing assembly is shown in a top view; Figure 3A shows a housing assembly in a third embodiment according to the present invention in a 3D view; and Figure 3B Shown in 3D view Figure 3A A cooling structure of a housing assembly. DETAILED DESCRIPTION

[0025] Described below Figures 1A to 1K 1 shows a housing assembly 2 according to the present invention in a first embodiment. The housing assembly 2 is used for an electric drive device (not shown) of a motor vehicle. Figure 1A , 1B , 1D, 1F, 1G, 1J and 1K. The cooling fluid hollow structure formed by the components is shown in Figure 1C , 1E and 1H. The fluid section is denoted by F, supplemented by the corresponding reference symbols of the relevant components. This also applies to Figures 2A to 2C and Figures 3A to 3B The embodiment shown.

[0026] The housing assembly 2 includes a motor housing portion 3 , a case 4 and an inverter housing portion 5 .

[0027] The motor housing part 3 comprises a jacket part 6 for accommodating the stator of the electric motor and a first gear housing part 7 for accommodating components of the gear arrangement. The jacket part 6 and the first gear housing part 7 are integrally formed, for example by casting light metal.

[0028] The housing 4 can be mounted to the jacket part 6 by means of suitable connectors 11, for example by means of circumferentially distributed flanges and / or bolted connectors. In the mounted condition, the housing 4 and the inner jacket part 6 are arranged coaxially and form a motor cooling channel 8 through which a cooling fluid F can flow to cool the motor (not shown). The cooling channel 8 is arranged radially between the inner jacket part 6 and the outer housing 4 and extends helically around the motor axis A1. In this way, the heat transferred from the motor to the inner jacket part 6 can be absorbed by the cooling fluid F flowing through the motor jacket. The housing 4 can also be referred to as an outer jacket part.

[0029] The first gear housing part 7 comprises circumferentially distributed connecting elements 9. The connecting elements 9 are configured as flange connectors, which are to be mounted to corresponding second connecting elements 10 of the inverter housing part 5, which can also be configured as flange connectors. The first gear housing part 7 also comprises a through hole 12 for a first output shaft of a gearbox (not shown). The axis A2 of the through hole 12 extends parallel to the motor axis A1. In addition, the first gear housing part can optionally include a bearing seat 36 for an intermediate shaft of a gear arrangement (not shown).

[0030] The inverter housing portion 5 includes an inverter housing portion 13 and a second gear housing portion 14 for accommodating an inverter of an electric motor (not shown). The inverter housing portion 13 and the second gear housing portion 14 are integrally formed and can be made of a casting, for example, a light metal material. The inverter housing portion 13 is arranged axially adjacent to the second gear housing portion. More specifically, the inverter housing portion 13 forms an axial end of the housing assembly 2 relative to the motor axis A1. The inverter housing portion 13 has an opening in the axial direction so that the inverter can be axially installed therein. A cover 15 can be provided to close the inverter housing portion 13 so that the inverter is encapsulated in the inverter housing. The cover 15 can be mounted to the inverter housing portion 13 by corresponding connecting elements 24. For example, the inverter housing portion 13 can optionally include a chamber 39 for receiving electronic components, which can be closed by a cover 40.

[0031] When the machine is operated in motor mode, the inverter supplies power from the battery to the motor. When the motor is operated in generator mode, the inverter feeds power to the battery of the motor vehicle. The inverter can convert the AC power generated by the motor into DC power to charge the battery and vice versa. The inverter may include capacitors, intelligent power generation modules (IPGMs) and busbars. During operation, the components of the inverter heat up and the heat generated needs to be dissipated by a cooling system.

[0032] To this end, the inverter housing part 5 includes a fluid connector 16, which is fluidically connected to a cooling chamber 17 in the inverter housing part 13. The cooling chamber 17 has an inlet 18 and an outlet 19, so that the cooling fluid can flow from the connector 16 through the cooling chamber 17 and then further to the gear housing part 14. The cooling chamber 17 includes a circumferential connection surface 20, to which components of the inverter can be connected in a fluid-tight manner. Therefore, the inverter components extending into the cooling chamber 17 are cooled by the fluid flowing through the chamber.

[0033] The second gear housing portion 14 includes a gearbox cooling passage 22 that is fluidly connected to the outlet 19 of the inverter cooling chamber 17. Figure 1C , 1E 1J, the gearbox cooling channel 22 has a C-shaped shape in a cross-sectional view. The second gear housing part 14 also includes a second through hole 23 for the second output shaft, the axis A2 of the shaft opening extending parallel to the motor axis A1. The C-shaped gearbox cooling channel 22 extends at least 180° in the circumferential direction relative to the axis A2 of the shaft opening of the second gear housing part 14. The second gear housing part 14 can optionally include a second bearing seat 37 for an intermediate shaft of the gear device, wherein the second bearing seat 37 and the first bearing seat 36 form a rotation axis A3 extending parallel to the motor axis A1 in the installed state.

[0034] The inverter housing part 5 may optionally have an intermediate cooling channel 29 (in Figure 1D ), the intermediate cooling channel 29 may be arranged between the inverter cooling chamber 17 and the gearbox cooling channel 22. Therefore, the cooling fluid may flow from the cooling chamber 17 to the gearbox cooling channel 22 through the intermediate cooling channel 29. Similar to the gearbox cooling channel 22, the intermediate cooling channel 22 may have a C-shape in a cross-sectional view. However, the intermediate cooling channel 29 is preferably arranged axially offset from the gearbox cooling channel 22. In particular, the intermediate cooling channel 29 is arranged to extend in a circumferential direction around the motor axis A1, for example, extending at least 180°.

[0035] On its side facing the first gear housing part 7, the second gear housing part 14 comprises circumferentially distributed second connecting elements 10 for providing a mechanical connection with the motor housing part 3. Furthermore, a connecting channel 26 is formed between the motor housing part 3 and the inverter housing part 5 in order to fluidically connect the cooling structures of the housing parts.

[0036] The first connection element 9 and the second connection element 10 can be connected to each other in order to sealably connect the motor housing part 3 and the inverter housing part 5. In the installed state, the motor housing part 3 forms a first half of the housing of the gearbox, and the inverter housing part 5 forms a second half of the housing of the gearbox. In other words, the interface of the two housing parts 3, 5 is located in the area of ​​the gearbox housing. The first and second connection elements 9, 10 can include flanges and bolts, but are not limited thereto. For example, the two housing parts can also be welded to each other.

[0037] In the connected condition, the cooling structure 35 of the inverter housing part 5 is fluidically connected to the cooling structure 33 of the motor housing part 3 via the connecting channel 26. The first connecting channel 26 can be formed from the end section of the gearbox cooling channel 22 to the inlet section 28 of the motor cooling channel 8. The cooling structure of the motor and inverter housing parts 3, 5 forms part of a closed cooling circuit from the fluid connector 16 of the inverter housing part 5 via the inverter cooling chamber 17, the gearbox cooling channel 22, the motor cooling channel 8 and to the fluid connector 31 of the motor housing part 3. The flow path P of the cooling fluid F is composed of Figure 1C The return path (not shown) may be arranged between the motor housing connector 31 and the inverter housing connector 16. The return path may include a heat exchanger to cool the cooling fluid that has absorbed heat when flowing through the housing assembly 2. The heat exchanger may be arranged outside the housing assembly 2.

[0038] An exemplary fluid coupling between the inverter housing portion 5 and the motor housing portion 3 is Figure 1K Detailedly shown in . The fluid coupling may include a sleeve-shaped connector 21, wherein the first portion 38 is connected to the motor-side cooling channel and the second portion 38' is connected to the inverter-side cooling channel. The connector 21 is particularly configured to form a liquid-tight seal between the motor-side cooling channel and the inverter-side cooling channel. The connector 21 may be made of an elastic material, such as rubber or other similar plastic material. The connector 21 may have a sealing lip or other sealing feature at its axial end to sealably contact the circumferential surface of the channel connecting portion 25 of the motor housing portion 3 and the relative channel connecting portion 25' of the inverter housing portion 5, respectively. The inverter housing portion 5 may have an optional auxiliary hole 41, which forms a part of the connecting channel 26 and can be closed to the outside with a plug (not shown). Alternatively, the two relative channel connecting portions 25, 25' may also be fluidically connected to each other without a separate connector, for example by including a sealing ring in the contact area between the two housing portions 3, 5.

[0039] In the installed state, the housing assembly 2 is part of an electric drive device configured to drive a motor vehicle. The electric drive device includes a motor received in a motor housing portion 3, a gear device for transmitting the rotational motion of the motor, and an inverter for controlling and monitoring the motor and ensuring that the torque supply and speed control meet the requirements. The motor includes a stator and a rotor (not shown), wherein the stator is connected to the housing 4 of the motor housing portion 3 in a rotationally fixed manner. The rotor is drivingly connected to a rotor shaft, which is rotatably supported in the housing assembly 2 around the motor axis A1. The gear device (not shown) is configured to transmit the rotational motion from the rotor shaft to the first and second output shafts. To this end, the gear device may include a transmission unit having an optional intermediate shaft rotatable around the axis A3, and a differential unit that distributes the input motion to the two output shafts. The inverter (not shown) is arranged in the inverter shell portion 13 of the inverter housing portion 5.

[0040] In the following, the specific features of different embodiments will be described. Figures 1A to 1K In the first embodiment shown, there is only one connecting channel 26 between the motor housing part 3 and the inverter housing part 5. The entire cooling fluid F flows from the inverter housing part 5 through the channel 26 to the motor housing part 3, where the cooling fluid F leaves the housing assembly 2 and can return again to the inverter housing part 5 via a return path (not shown).

[0041] Figures 2A to 2C The embodiments shown in correspond broadly to Figures 1A to 1K The embodiments shown in FIG. 1 are therefore referred to the above description with regard to common features. Figures 1A to 1K Identical and / or corresponding details may be provided with the same reference numerals.

[0042] Figures 2A to 2C The special feature of the second embodiment shown is that in addition to the first connecting channel 26, a second connecting channel 30 is provided to fluidically connect the first and second cooling structures. In this case, the cooling fluid F flows functionally in parallel, wherein the first coolant flow F26 flows from the inverter cooling chamber 17 indirectly to the motor housing part 3 via the gearbox cooling channel 22, and the second coolant flow F30 flows directly to the motor housing part 3, i.e. bypassing the gearbox cooling channel 22. The cooling structure 35 of the inverter housing part 5 is formed so that preferably at least 30%, for example 50%, of the coolant flowing into the inverter housing part 3 through the connector 16 is diverted in the flow path behind the cooling chamber 17 and is directed directly to the motor cooling channel 8 through the second connecting channel 30. The other half of the coolant flows indirectly to the motor cooling channel 8 via the gearbox cooling channel 22. In the motor cooling channel 8, the two fluid flows F26, F30 merge and flow together through the motor jacket.

[0043] like Figure 2B and 2C As shown, a connecting passage (F32) is formed between the outlet 19 of the inverter cooling chamber 17 and the intermediate cooling passage 29. At the end (F34), the intermediate passage 29 is connected to the second cooling passage 30. Therefore, the first coolant flow F1 flows to the gearbox passage 22 through the intermediate passage 29, and the second coolant flow F30 flows through the second connecting passage 30 from the end (F34) of the intermediate passage 29.

[0044] Figure 3A and 3B The illustrated embodiments correspond broadly to Figures 2A to 2C The embodiments shown are therefore referenced to the above description with regard to common features. In this respect, identical and / or corresponding details are provided with Figures 2A to 2C and Figures 1A to 1K The same reference numerals are used in the drawings.

[0045] Figure 3A and 3B The only difference of the illustrated embodiment is that the outlet 19 of the cooling chamber 17 is connected directly to the motor cooling channel 8 via a second connecting channel 30 .

[0046] Reference numerals 2 Shell assembly 3 Motor housing 4 Cabinet 5 Inverter housing 6 Sheath part 7 First gear housing part 8 Motor cooling channels 9 First connecting element 10 Second connecting element 11 Connectors 12 Through Holes 13 Inverter housing 14 Second gear housing part 15 Cover 16 Fluid Connectors (5) 17 Cooling Chamber 18 Entrance 19 Exit 20 Connection surface 21 Fluid connector 22 Gearbox cooling channel 23 Through Holes 24 Connecting elements 25, 25' connection section 26First Connection Channel 27 End section (22) 28 Entrance section (8) 29 Intermediate cooling channel 30 Second connection channel 31 Fluid connector 32 connection channels 33 Cooling structure (3) 34 End section (32) 35 Cooling structure (5) 36 Bearing seat (7) 37 Bearing seat (14) 38, 38' section 39 Chamber 40 Cover 41 Auxiliary hole A axis F Coolant P Flow path.

Claims

1. A housing assembly for an electric drive device for driving a motor vehicle, comprising: A motor housing part (3) having a jacket part (6) for accommodating a stator of an electric motor and a first gear housing part (7) for accommodating components of a gear arrangement, wherein the jacket part (6) and the first gear housing part (7) are integrally formed, A housing (4) mountable to a jacket part (6), wherein in the mounted condition the housing (4) and the jacket part (6) are arranged coaxially with respect to the motor axis (A1), and comprises a motor cooling channel (8) through which a cooling fluid (F) can flow to cool the motor, An inverter housing portion (5) having an inverter housing portion (13) for accommodating an inverter of an electric machine and a second gear housing portion (14) formed integrally with the inverter housing portion (13), wherein the inverter housing portion (13) is arranged axially adjacent to the second gear housing portion (14) and includes a fluid connector (16) fluidically connected to a cooling chamber (17) in the inverter housing portion (13), wherein the second gear housing portion (14) includes a gearbox cooling passage (22) fluidly connected to the cooling chamber (17), The first gear housing part (7) and the second gear housing part (14) can be mechanically connected to each other via connecting elements (9, 10), In the connected state, a closed cooling circuit is formed from the fluid connector (16) of the inverter housing part (5) via the cooling chamber (17) and the gearbox cooling channel (22) to the motor cooling channel (8).

2. The housing assembly according to claim 1, Features The inverter housing part (13) forms an axial end of the housing assembly (2) relative to the motor axis (A1).

3. The housing assembly according to claim 1 or 2, Features The gearbox cooling channel (22) has a C-shape in a cross-sectional view and extends circumferentially at least 180° relative to a gearbox axis (A2) parallel to the motor axis (A1).

4. The housing assembly according to any one of claims 1 to 3, Features The inverter housing portion (5) includes an intermediate cooling passage (29) fluidly arranged between the inverter cooling chamber (17) and the gearbox cooling passage (22).

5. The housing assembly according to claim 4, Features The intermediate cooling channel (29) has a C-shape in a cross-sectional view and extends circumferentially over at least 180° relative to the motor axis (A1).

6. The housing assembly according to any one of claims 1 to 5, Features A first connecting channel (26) is formed between the motor housing portion (3) and the inverter housing portion (5) to fluidically connect a cooling structure (33) of the motor housing portion (3) with a cooling structure (35) of the inverter housing portion (5).

7. The housing assembly according to any one of claims 1 to 6, Features A return path is arranged between a fluid connector (31) of a motor housing portion (3) and a fluid connector (16) of an inverter housing portion (5), wherein a heat exchanger is arranged in the return path outside the motor housing portion (3) and the inverter housing portion (5) to cool a cooling fluid flowing therethrough.

8. The housing assembly according to claim 6 or 7, Features A first connecting passage (26) is formed from an end section of the gearbox cooling chamber (22) to an inlet section (18) of the motor cooling passage (8).

9. The housing assembly according to any one of claims 6 to 8, Features A second connecting channel (30) is formed between the motor housing part (3) and the inverter housing part (5), and is functionally arranged parallel to the first connecting channel (26).

10. The housing assembly according to claim 9, Features At least 30% of the cooling fluid flowing through the inverter housing portion (5) flows directly to the motor cooling channel (8) through the second connecting channel (30), and the remaining cooling fluid flows indirectly to the motor cooling channel (8) through the first connecting channel (26).

11. The housing assembly according to claim 9 or 10, Features The second connecting channel (26) connects the intermediate cooling channel (29) of the inverter housing part (5) with the second inlet (18) of the motor cooling channel (8).

12. The housing assembly according to claim 9 or 10, Features The second connecting channel (30) connects the cooling chamber (17) of the inverter housing part (5) with the second inlet of the motor cooling channel (8).

13. The housing assembly according to any one of claims 1 to 12, Features A cover (15) is provided to close the inverter housing portion (13).

14. An electric drive device for driving a motor vehicle, comprising: The housing assembly (2) according to any one of claims 1 to 13, An electric machine comprising a stator and a rotor, wherein the stator is connected in a rotationally fixed manner and axially to a jacket portion (6) of a motor housing portion (3), wherein the rotor is drivingly connected to a rotor shaft which is rotatably supported in a housing assembly (2) about a motor axis (A1), a gear arrangement for transmitting the rotational movement of the rotor shaft to a first output shaft extending through a first opening (12) of the motor housing part (3) and a second output shaft extending through a second opening (23) of the inverter housing part (5), and An inverter is arranged in an inverter housing part (13) of an inverter housing part (5).

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