Non-drive end housing element for an electric machine housing of an

Abstract

The invention relates to a non-drive-end housing element (6) for an electric drive assembly (1) of a vehicle, the non-drive-end housing element (6) being configured to be associated with an electric machine (2) and comprising:-a cover comprising a rear wall and an outer skirt for accommodating one end of the electric machine (2) and comprising a flange equipped with a first sealing washer; -the rear wall of the cover comprises an opening for the passage of the rotor shaft (9) and opening in a recess for receiving the angular position sensor, said recess being arranged on a second side of the non-drive-end housing element (6) opposite the first side and being formed by a recess edge equipped with a second sealing washer; -the rear wall of the cover further comprises a hole for the passage of an electrical connection assembly (18) for connecting the motor (2) to the motor control module (4); the non-driving end housing element (6) comprises a boss surrounding the bore, the boss being equipped with a third sealing washer.

Description

Technical Field

[0001] The present invention relates to the field of electric or hybrid vehicles.

[0002] More specifically, the present invention relates to a non-drive end housing element of a motor housing of an electric drive assembly for a vehicle, an electric drive assembly including the non-drive end housing element, and a vehicle including the electric drive assembly. Background Art

[0003] An electric drive assembly generally includes a rotating electric machine, a gearbox assembly, an electric machine control module, an electrical connection assembly connecting the electric machine control module to the rotating electric machine, and sensors, such as an angular position sensor for transmitting the angular position of a rotor shaft. The electric drive assembly includes a plurality of sealing interfaces, and more specifically: a sealing interface on one side of the closed motor housing between the motor housing and the non-drive end housing element, a sealing interface ensuring the sealing of the electrical connection assembly, and a sealing interface ensuring the sealing of a recess for accommodating the angular position sensor.

[0004] These sealing interfaces are manufactured by several sub-assemblies, which makes mass assembly and reliable sealing difficult to achieve. Summary of the Invention

[0005] Therefore, a basic concept of the present invention is to propose an electric drive assembly that is easier to assemble and provides a more reliable sealing interface.

[0006] To this end, according to a first aspect, the present invention provides a non-drive end housing element of an electric drive assembly for a vehicle, the non-drive end housing element being configured to be associated with an electric machine, the electric machine including a rotor, a stator, and a motor housing that are non-rotatably connected to a rotor shaft, the rotor and the stator being at least partially received in the motor housing; the non-drive end housing element includes:

[0007] - a cover protruding from a first side of the non-drive end housing element and including a rear wall and an outer skirt for receiving one end of the electric machine, and the outer skirt including a flange equipped with a first sealing gasket for ensuring the sealing between the cover and the motor housing;

[0008] - the rear wall of the cover includes an opening for the rotor shaft to pass through and opening into a recess for accommodating the angular position sensor, the recess being arranged on a second side of the non-drive end housing element opposite to the first side and being formed by an axially protruding recess edge equipped with a second sealing gasket for ensuring the sealing between the recess edge and a recess cover;

[0009] - The rear wall of the cover further includes a hole for the electrical connection assembly to pass through, and the electrical connection assembly is used to connect the motor to the motor control module; the non-drive end housing element includes a boss around the hole on the second side, and the boss is equipped with a third sealing gasket, and the third sealing gasket is used to ensure the seal between the boss and the housing of the motor control module.

[0010] Therefore, such a non-drive end housing element can tightly connect the motor housing, the motor control module and the recess cover, and provide a sealed interface for the aforementioned elements. This makes it possible to concentrate the sealed interface on the same element, reduce the mechanical stress in the assembly, and simplify the assembly of the entire electric drive assembly.

[0011] According to an embodiment, such a non-drive end housing element may have one or more of the following features.

[0012] According to one embodiment, at least one of the first, second and third sealing gaskets is a field-curing gasket. Advantageously, all the first, second and third sealing gaskets are field-curing gaskets.

[0013] This further simplifies the manufacturing process by avoiding the handling of prefabricated joints that tend to malfunction during the automation process.

[0014] According to one embodiment, the rear wall of the cover includes an annular skirt portion, which is arranged around the opening and forms a bearing receiving portion for receiving a bearing that is arranged to rotatably guide the rotor shaft.

[0015] According to one embodiment, the recess edge includes a window that passes through the recess edge and leads to the recess, and the window is designed to receive a connector for connecting to an angular position sensor and the motor control module.

[0016] According to one embodiment, the rear wall of the cover includes a hole for positioning a sensor, such as a temperature sensor.

[0017] According to one embodiment, the flange has a plurality of holes that enable the outer skirt portion to be attached to the motor housing.

[0018] According to one embodiment, the recess edge includes a plurality of holes that enable the recess cover to be attached to the non-drive end housing element to close the recess.

[0019] According to one embodiment, the non-drive end housing is made as one piece, advantageously molded from a metal or alloy material.

[0020] According to one embodiment, the non-drive end housing element includes a plurality of holes arranged on the second side that enable the housing of the motor control module to be attached to the non-drive end housing element.

[0021] According to one embodiment, the present invention further provides an electric drive assembly, including the aforementioned non-drive end housing element, an angular position sensor received in the recess, a recess cover attached to the edge of the recess, and an electric motor. The electric motor includes a rotor non-rotatably connected to the rotor shaft, a stator, and a motor housing. The rotor and the stator are at least partially received in the motor housing. One end of the motor is received in the cover, the motor housing is fastened to the flange of the cover, and the rotor shaft passes through the opening.

[0022] According to one embodiment, the electric drive assembly further includes a motor control module and an electrical connection assembly attached to the non-drive end housing element. The electrical connection assembly passes through the hole and is connected to the interconnect of the motor and the electrical connector of the motor control module. The motor control module includes a housing, and the housing includes a protruding portion. The protruding portion is positioned opposite to the boss and presses against the third sealing washer. The protruding portion includes a hole allowing a tool to pass through to fix the electrical connection assembly to the electrical connector of the motor control module. A fourth sealing washer is arranged around the hole of the protruding portion and ensures the seal between the second cover and the protruding portion.

[0023] According to one embodiment, the motor control module includes an inverter configured to convert direct current into alternating current for input to the motor.

[0024] According to one embodiment, the present invention further provides a motor vehicle including the aforementioned electric drive assembly. Description of the Drawings

[0025] With reference to the accompanying drawings, through the following description of multiple embodiments of the present invention, the present invention will be better understood, and other objects, details, features, and advantages of the present invention will also become clearer. These embodiments are given by way of illustration only and not by way of limitation.

[0026] Figure 1 is a schematic diagram of the electric drive assembly.

[0027] Figure 2 is a perspective view of the non-drive end housing element, showing the side intended to face the motor.

[0028] Figure 3 is a perspective view of the non-drive end housing element, showing the side intended to face the motor control module.

[0029] Figure 4 is a detailed perspective view of the non-drive end housing element and the protruding portion of the motor control module.

[0030] Figure 5 is a cross-sectional view showing the electrical connection assembly and the protruding portion of the motor control module. Detailed Description of the Embodiments

[0031] In the description and claims, the terms "outer" and "inner" and "axial" and "radial" orientations will be used to specify elements of the electric drive assembly according to the definitions given in the description. By convention, the rotational axis X of the rotor of the rotary electric machine defines the "axial" orientation. The "radial" orientation is orthogonal to the axis X and extends from the inside out away from the axis X.

[0032] The electric drive assembly 1 is designed to equip a hybrid or electric motor vehicle.

[0033] As Figure 1 shown, the electric drive assembly 1 includes an electric machine 2, a gearbox assembly 3, and an electric machine control module 4. The electric drive assembly 1 further includes an electric machine housing 5 in which the electric machine 2 is arranged, and the electric machine housing 5 has a generally shape of a rotating cylinder, for example. The electric machine housing 5 is closed on one side (i.e., the drive end) by a cover of the gearbox assembly 3 and on the other side (i.e., the non-drive end) by a non-drive end housing element 6.

[0034] The electric machine 2 is, for example, a permanent magnet synchronous electric machine or an alternating current asynchronous electric machine. The electric machine 2 includes a rotor 7 and a stator 8. In the illustrated embodiment, the stator 8 radially surrounds the rotor 7, and the electric machine 2 is a radial flux rotary electric machine. However, in an embodiment not shown, the electric machine 2 is an axial flux rotary electric machine, which means that it has at least one stator axially opposite to at least one rotor, such that the gap between the rotor and the stator and thus the flux direction between the two are aligned parallel to the rotational axis instead of radially.

[0035] The stator 8 includes an iron core that carries windings. The iron core is formed with a plurality of grooves, and the windings are inserted into the interior of the grooves. The iron core includes, for example, a plurality of plates, such as electrical steel sheets, which are laminated and pressed against each other to form a lamination.

[0036] According to an embodiment in which the electric machine 2 is a permanent magnet synchronous electric machine, the rotor 7 includes permanent magnets that generate a magnetic field synchronous with the rotating magnetic field generated by the stator windings. According to an alternative embodiment in which the electric machine is an alternating current asynchronous electric machine, the rotor 7 made of a conductive material induces a current due to the changing magnetic field, and this current in turn generates a secondary magnetic field that interacts with the magnetic field of the stator, thereby causing the rotor to move.

[0037] The rotor 7 is rotatably mounted on the electric machine housing 5 about the rotational axis X. More specifically, the rotor 7 is non-rotatably connected to a rotor shaft 9, and the rotor shaft 9 is rotatably mounted along the X-axis. In Figure 1 the illustrated embodiment, the rotor shaft 9 is rotatably guided by a pair of bearings 10, 11 that are respectively received in a bearing housing 16 (as Figure 2 shown) and a bearing housing 17, and the bearing housing 16 is arranged in the non-drive end housing element 6, and the bearing housing 17 is arranged in the cover of the gearbox assembly 3.

[0038] The rotor shaft 9 passes through at least one hole 12 arranged in the cover of the gearbox assembly 3 to be coupled to the gear input shaft (not shown) of the gearbox assembly 3. The gear input shaft is, for example, coaxially arranged with the rotor shaft 9 and thus receives the torque from the electric motor 2. It should be understood that the rotor shaft 9 and the gear input shaft can be two different shafts rotatably connected by a connecting element (e.g., by a spline connection) or can be the same shaft.

[0039] In the illustrated embodiment, the electric drive assembly 1 is longitudinally arranged between two wheels. In other words, the rotational axis X of the electric motor 2 is parallel to the wheel axle. In addition, the gearbox assembly 3 further includes a differential assembly (not shown), which is coupled to the gearbox input shaft by a gear set. The differential assembly allows the wheels to rotate at different speeds and distributes the torque and load between the wheel axles. In the illustrated embodiment, one of the wheel axles 15 passes through holes 13, 14 arranged in the motor housing 5 and the non-driven end housing element 6.

[0040] The electric drive assembly 1 includes an electrical connection assembly 18 configured to electrically connect the motor control module 4 to the stator 8 of the electric motor 2, more precisely, to the interconnect of the stator 8. Such an interconnect (not shown) is configured to connect the windings of the stator 8 to the electrical connection assembly 18. The electrical connection assembly 18 passes through a hole 19 arranged in the non-driven end housing element 6, which will be described below in conjunction with Figure 2 and Figure 3 will be described.

[0041] As Figure 1 shown, the electrical connection assembly 18 includes a plurality of busbars (e.g., copper busbars). The number of busbars can be four, respectively for three-phase current and the neutral line.

[0042] In conjunction with Figure 2 and Figure 3 , the features of the non-driven end housing element 6 according to an embodiment will now be described. The non-driven end housing element 6 is advantageously made in one piece and preferably molded from a metal or alloy material. Figure 2 shows the side of the non-driven end housing element 6 facing the electric motor 2, while Figure 3 shows the side of the non-driven end housing element 6 facing the motor control module 4.

[0043] As Figure 2As shown, the non-driving end housing element 6 includes a cover 20 which projects towards the motor housing 5, and one end of the motor 2 is received within the cover 20. The cover 20 has an outer skirt 21 and a rear wall 22. The cover 20 is fastened to the motor housing 5. For this purpose, the end of the outer skirt 21 includes a flange 23 which has a plurality of orifices 24 distributed around the axis X such that the outer skirt 21 can be attached to the motor housing 5 by fastening elements (such as screws). In addition, the flange 23 is equipped with a sealing gasket 25 which is used to ensure the seal between the cover 20 and the motor housing 5.

[0044] According to a preferred embodiment, the sealing gasket 25 is a Cure-In-Place gasket (CIPG). Such a sealing gasket 25 is achieved by applying a liquid form of joint and then curing it to form a solid, uniform compression joint. For example, the sealing gasket 25 is made of a material selected from silicone and polyurethane. The curing process can be achieved by ultraviolet light, heating or a multi-component system reaction. According to another embodiment, the sealing gasket 25 is prefabricated and subsequently installed in a corresponding groove arranged in the flange 23.

[0045] The rear wall 22 of the cover 20 has an opening 26 through which the rotor shaft 9 of the motor 2 can pass. Thus, as will be described below, an angular position sensor configured to transmit a signal representative of the angular position of the rotor shaft 9 can be arranged on the other side of the non-driving end housing element 6.

[0046] The rear wall 22 of the cover 20 further includes an annular skirt 27 surrounding the opening 26, and the annular skirt 27 constitutes a bearing receiving portion 16 which is used to receive one of the two bearings 10, 11 that rotatably guide the rotor shaft 9.

[0047] The rear wall 22 of the cover 20 further includes a hole 19 through which an electrical connection assembly 18 passes, and the electrical connection assembly 18 electrically connects the motor control module 4 and the stator 8 of the motor 2, and the motor control module 4 and the stator 8 of the motor 2 are respectively arranged on both sides of the non-driving end housing element 6.

[0048] In the illustrated embodiment, the rear wall 22 further includes a hole 28 for positioning a temperature sensor which is configured to transmit a signal representative of the temperature of the rotor 7 and / or the stator 8.

[0049] In the illustrated embodiment, the non-driving end housing element 6 further includes a hole 14 through which one of the wheel shafts 15 passes.

[0050] As Figure 3As shown, the non-drive end housing element 6 includes a recess 29. An opening 26 for the rotor shaft 9 leads to this recess 29, and the recess is defined by a recess edge 30 which projects axially towards the motor control module 4. The recess 29 provides a receiving portion for the angular position sensor. As Figure 1 shown, the recess 29 is intended to be closed with a recess cover 31. For this purpose, a plurality of orifices 32, such as threaded orifices, are provided on the side of the recess 29. The plurality of orifices 32 are arranged in the recess edge 30 such that the recess cover 31 can be attached to the non-drive end housing element 6 by fastening elements (such as screws).

[0051] The recess edge 30 is provided with a sealing washer 33 which is used to ensure a seal between the recess edge 30 and the recess cover 31. The sealing washer 33 is advantageously a cured-in-place gasket (CIPG), but alternatively, it can be a prefabricated gasket received in a groove formed in the recess edge 30.

[0052] The non-drive end housing element 6 includes a window 34 which is arranged in the recess edge 30 and passes through the recess edge 30 so as to lead to the recess 29. As Figure 1 shown, the window 34 is designed to receive a connector 35. The connector 35 is used on the one hand to connect to the angular position sensor and on the other hand to connect to the motor control module 4, and thus can transmit a signal representing the angular position of the rotor shaft 9 from the angular position sensor to the motor control module 4. According to an advantageous embodiment, a temperature sensor arranged in a hole is also electrically connected to the connector 35.

[0053] According to one embodiment, the angular position sensor is a resolver. The resolver includes a resolver rotor and a resolver stator. The resolver rotor is attached to the end of the rotor shaft 9 which projects into the recess 29, and the resolver stator surrounds the resolver rotor. The resolver stator is electrically connected to the connector. According to an alternative embodiment, the angular position sensor is an absolute encoder. The absolute encoder includes on the one hand a disc which is attached to the end of the rotor shaft 9 projecting into the recess 29. The disc includes a coded track representing absolute angle information, and on the other hand a reading head or sensor which is configured to detect the coded information on the disc when the disc rotates.

[0054] The non-drive end housing element 6 further includes a plurality of orifices 36, such as threaded orifices, which are arranged on its side facing the motor control module and such that the housing of the motor control module 4 can be attached to the non-drive end housing element 6 by fastening elements (such as screws).

[0055] The motor control module 4 is advantageously an inverter which is configured to convert direct current (DC) into alternating current (AC) for input to the motor 2. The inverter is also configured to control and regulate the output frequency and voltage.

[0056] The non-driving end housing element 6 includes a boss 37 that surrounds a hole 19 for the electrical connection assembly 18 to pass through. The boss 37 projects axially towards the motor control module 4 and is for facing a corresponding opening made in the housing of the motor control module 4. In addition, the boss 37 is equipped with a sealing gasket 38 that is for ensuring a seal between the boss 37 and the housing of the motor control module 4. The sealing gasket 38 can be a field-cured gasket (CIPG) or a prefabricated gasket.

[0057] As Figure 4 and Figure 5 shown, the housing of the motor control module 4 includes a protruding portion 39 that is positioned opposite to the boss 37 and presses against the sealing gasket 38. The protruding portion 39 includes a hole 40 that allows a tool such as a screwdriver to pass through for fixing the bus bar of the electrical connection assembly 18 to the electrical connector of the motor control module 4. In addition, the protruding portion 39 further includes a plurality of orifices 42, such as threaded orifices, such that a second cover (not shown) can be attached to the protruding portion 39. In addition, a sealing gasket 41 is arranged around the hole 40 for ensuring a seal between the second cover and the protruding portion 39.

[0058] Although the present invention has been described in connection with a plurality of embodiments, it is obvious that the present invention is in no way limited to these embodiments and includes all technical equivalents of the described means and their combinations, provided that these combinations fall within the scope of the claimed invention.

[0059] The use of the verb “comprise”, “include” or “contain” and their conjugations does not exclude the presence of other elements or steps not mentioned in the claims.

[0060] In the claims, any reference signs in parentheses shall not be construed as limiting the claim.

Claims

1. A non-drive end housing element (6) for an electric drive assembly (1) of a vehicle, the non-drive end housing element (6) being configured to be associated with an electric machine (2) comprising a rotor (7) non-rotatably connected to a rotor shaft (9), a stator (8), and a machine housing (5), the rotor (7) and the stator (8) being at least partially received in the machine housing; the non-drive end housing element (6) comprising: - a cover (20) protruding from a first side of the non-drive end housing element (6) and comprising a rear wall (22) and an outer skirt (21), the outer skirt for receiving one end of the electric machine (2), and the outer skirt comprising a flange (23) equipped with a first sealing gasket (25) for ensuring a seal between the cover (20) and the machine housing (5); - the rear wall (22) of the cover (20) comprises an opening (26) for the rotor shaft (9) to pass through and opening into a recess (29) for receiving an angular position sensor, the recess (29) being arranged on a second side of the non-drive end housing element (6) opposite the first side and being formed by a recess edge (30) that axially protrudes and is equipped with a second sealing gasket (33) for ensuring a seal between the recess edge (30) and a recess cover (31); - the rear wall (22) of the cover (20) further comprises a hole (19) for an electrical connection assembly (18) for connecting the electric machine (2) to a motor control module (4) to pass through; the non-drive end housing element (6) comprises a boss (37) around the hole (19) on the second side, the boss (37) being equipped with a third sealing gasket (38) for ensuring a seal between the boss (37) and the housing of the motor control module (4).

2. The non-driving end housing element (6) according to claim 1, wherein, At least one of the first, second, and third sealing gaskets (25, 33, 38) is a field-curing gasket.

3. The non-driving end housing element (6) according to claim 1 or 2, wherein, The rear wall (22) of the cover (20) comprises an annular skirt (27) arranged around the opening (26), and the annular skirt forms a bearing receiving portion (16) for receiving a bearing (10) arranged to rotatably guide the rotor shaft (9).

4. The non-driving end housing element (6) according to any one of claims 1 to 3, wherein, The recess edge (30) comprises a window (34) passing through the recess edge (30) and leading to the recess (29), the window (34) being designed to receive a connector (35) for connection to the angular position sensor and the motor control module (4).

5. The non-driving end housing element (6) according to any one of claims 1 to 4, wherein, The rear wall (22) of the cover (20) comprises a hole (28) for positioning a sensor such as a temperature sensor.

6. The non-drive end housing element (6) according to any one of claims 1 to 5, wherein, The flange (23) has a plurality of apertures enabling the outer skirt (21) to be attached to the machine housing (5).

7. The non-drive end housing element (6) according to any one of claims 1 to 6, wherein, The recess edge (30) includes a plurality of apertures (32) enabling the recess cover (31) to be attached to the non-drive end housing element (6) to enclose the recess (29).

8. The non-drive end housing element (6) according to any one of claims 1 to 7, including a plurality of apertures (36) arranged on the second side and enabling the housing of the motor control module (4) to be attached to the non-drive end housing element (6).

9. An electric drive assembly (1) includes the non-drive end housing element (6) according to any one of claims 1 to 9, an angular position sensor received in the recess (29), a recess cover (31) attached to the recess edge, and a motor (2). The motor (2) includes a rotor (7) non-rotatably connected to a rotor shaft (9), a stator (8), and a motor housing (5). The rotor (7) and the stator (8) are at least partially received in the motor housing. One end of the motor (2) is received in the cover (20), the motor housing (5) is fastened to the flange (23) of the cover (20), and the rotor shaft (9) passes through the opening (26).

10. The electric drive assembly (1) according to claim 9 further includes a motor control module (4) and an electrical connection assembly (18) attached to the non-drive end housing element (6). The electrical connection assembly (18) passes through the hole (19) and is connected to the interconnector of the motor (2) and the electrical connector of the motor control module (4). The motor control module (4) includes a housing which includes a protruding portion (39) positioned opposite the boss (37) and pressing against the third sealing washer (38). The protruding portion (39) includes a hole (40) allowing a tool to pass through to fix the electrical connection assembly (18) to the electrical connector of the motor control module (4). A fourth sealing washer (41) is arranged around the hole (40) of the protruding portion (39) and ensures a seal between the second cover and the protruding portion (39).

11. The electric drive assembly (1) according to claim 10, wherein, The motor control module (4) includes an inverter configured to convert direct current into alternating current for input to the motor (2).

12. A motor vehicle includes the electric drive assembly (1) according to claims 9 to 11.

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