Electric drive assembly system and vehicle

Abstract

Disclosed is an electric drive assembly system comprising a housing and the following located in the housing: a motor assembly comprising a motor shaft, the motor shaft comprising a first motor shaft end and a second motor shaft end; a gearbox assembly comprising an input shaft, the input shaft comprising a first input shaft end and a second input shaft end, the first input shaft end being inserted into the second motor shaft end and forming a coupling portion with the second motor shaft end, so that the input shaft and the motor shaft rotate coaxially together; first bearings supported at the first motor shaft end; and second bearings supported at the second input shaft end, wherein the coupling portion comprises a spline coupling part and a radial centring part, and the electric drive assembly system further comprises third bearings, the third bearings being supported, at the radial centring part, on the second motor shaft end. A vehicle comprising an electric drive assembly system as described above is further disclosed.

Description

[0001] ELECTRIC DRIVE ASSEMBLY SYSTEM AND VEHICLE

[0002] TECHNICAL FIELD

[0003] The present invention relates to an electric drive assembly system applicable to vehicles such as electric vehicles or hybrid vehicles. The present invention further relates to a vehicle that comprises such an electric drive assembly system.

[0004] BACKGROUND

[0005] An electric drive assembly system, as the core power source for an electric or hybrid vehicle, typically comprises a motor and a gearbox, wherein the motor shaft of the motor and the input shaft of the gearbox are coupled to each other to transmit torque, and will undergo high-speed rotation during operations. Therefore, it is necessary to ensure that the motor shaft of the motor and the input shaft of the gearbox are well centred relative to each other to avoid vibrations caused by radial eccentricity, as well as resultant noise and low transmission efficiency. Axial alignment between the motor shaft and the input shaft should also be ensured to further promote the robustness of the overall electric drive assembly system. Meanwhile, the structure should be compact to ensure stable coupling between the motor shaft and the input shaft of the gearbox, as well as stable support for the motor shaft and input shaft, thereby ensuring operations in an optimal state, and hence high transmission efficiency. However, no solution has been proposed in the prior art that allows these technical effects to be achieved simultaneously.

[0006] The present invention is intended to achieve these technical effects by means of a simple and compact structure.

[0007] SUMMARY OF THE INVENTION

[0008] To this end, the present disclosure proposes an electric drive assembly system comprising a housing and the following located in the housing: a motor assembly comprising a motor shaft, the motor shaft comprising a first motor shaft end and a second motor shaft end, a gearbox assembly comprising an input shaft, the input shaft comprising a i first input shaft end and a second input shaft end, the first input shaft end being inserted into the second motor shaft end and forming a coupling portion with the second motor shaft end, so that the input shaft and the motor shaft rotate coaxially together, first bearings supported at the first motor shaft end, and second bearings supported at the second input shaft end, wherein the coupling portion comprises a spline coupling part and a radial centring part; and the electric drive assembly system further comprises third bearings, the third bearings being supported, at the radial centring part, on the second motor shaft end.

[0009] Therefore, the electric drive assembly system proposed in the present disclosure can at least achieve the following technical effects. The coupling portion formed by the motor shaft of the motor assembly and the input shaft of the gearbox assembly comprises a spline coupling part and a radial centring part, which ensures torque transmission between the motor shaft and the input shaft, while ensuring that the motor shaft and the input shaft are well centred relative to each other to effectively avoid vibrations and noise caused by radial eccentricity between the motor shaft and the input shaft, and ensure effective torque transmission from the motor shaft to the input shaft of the gearbox assembly. Further, the use of the first, second, and third bearings as defined above helps to provide strong and stable support for the motor shaft and input shaft and thus for the motor assembly and the gearbox assembly, in a compact structure. Specifically, the layout of these three groups of bearings and the positioning of the coupling portion relative thereto and to the motor shaft and input shaft allow for particularly stable support of the input shaft of the gearbox assembly and the motor shaft, further reducing vibration and noise, allow for a microscopic shaping design of the teeth of the gears of the gearbox assembly to ensure that the gears operate in an optimal state to deliver optimal performance, and further facilitate noise reduction.

[0010] The electric drive assembly system proposed by the present invention may further comprise one or more of the following aspects, which may be used individually or in combination. In some embodiments, the radial centring part comprises a radial inner surface of the motor shaft and a radial outer surface of the input shaft which is in a clearance fit with the radial inner surface. Such a radial centring part ensures good centralisation while being very easy to machine and assemble, further improving cost-effectiveness.

[0011] In some embodiments, the radial centring part is arranged at the end of the second motor shaft end. This allows the third bearings to be close to the gears of the gearbox assembly to better support the gears, so that the gears, when subjected to stress, undergo reduced deformation and do not jolt up or down, thereby promoting stable operations of the system.

[0012] In some embodiments, the third bearings comprise a third bearing inner ring and a third bearing outer ring, the second motor shaft end is provided with a shoulder, a retaining ring is provided at a second axial end of the third bearing inner ring and on the second motor shaft end, and the third bearing inner ring abuts against the shoulder at a first axial end and abuts against the retaining ring at the second axial end. Thus, the axial positioning and retention of the motor shaft can be ensured with a very compact structure and in a simple way, promoting stable operations of the system.

[0013] In some embodiments, the electric drive assembly system further comprises a parking ratchet wheel sleeved onto the input shaft, wherein the retaining ring radially presses against the parking ratchet wheel. This further ensures both a compact structure and the axial positioning and retention of the motor shaft.

[0014] In some embodiments, the housing is provided with a third bearing seat for accommodating the third bearings, and the third bearing outer ring is retained axially by the third bearing seat and a first pressure plate fixed relative to the housing. This allows for the stable axial retention and positioning of the third bearings using a simple and compact structure.

[0015] In some embodiments, the first bearings comprise a first bearing inner ring and a first bearing outer ring, and an elastic member capable of applying an axial pretightening force to the first bearings is provided between the first bearing outer ring and the housing. The arrangement of an elastic member makes it possible to very simply and dynamically ensure the axial positioning of the motor shaft relative to the input shaft of the gearbox assembly, thereby ensuring torque transmission efficiency and promoting the robustness of the overall electric drive assembly system.

[0016] In some embodiments, the second bearings comprise a second bearing inner ring and a second bearing outer ring, the housing is further provided with a second bearing seat for accommodating the second bearings, and the second bearing outer ring is retained axially by the second bearing seat and a second pressure plate fixed relative to the housing. This allows for the stable axial retention and positioning of the second bearings using a simple and compact structure.

[0017] In some embodiments, the size of the second bearings is larger than the size of the first bearings and the size of the third bearings, and the size of the third bearings is larger than the size of the first bearings. This ensures optimal support for the motor shaft and input shaft in a cost-effective manner and by means of a compact configuration.

[0018] In some embodiments, the gearbox assembly adopts a two-stage helical gear parallel axis arrangement and comprises a differential. This allows a more compact overall structure to be achieved.

[0019] The present invention further relates to a vehicle comprising an electric drive assembly system as described above.

[0020] BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to describe more clearly the technical solutions provided by embodiments of the present disclosure, the drawings required by the embodiments will be briefly described below. It should be understood that the drawings described below show only some embodiments of the present disclosure and should not be construed as limiting the scope, and that those of ordinary skill in the art, without creative labour, can further obtain other relevant drawings on the basis of these drawings. Among the drawings:

[0022] Fig. 1 is a cross-sectional view of an electric drive assembly system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] An electric drive assembly system according to the embodiments of the present disclosure will be described in detail below with reference to the drawings. In order to make the objectives, technical solutions, and advantages of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be explained clearly and completely below with reference to the drawings for the embodiments of the present disclosure. Obviously, the described embodiments are only some, not all, embodiments of the present disclosure.

[0024] Thus, the detailed description, provided below and in conjunction with the drawings, of the embodiments of the present disclosure, rather than being intended to limit the scope of the present disclosure for which protection is claimed, merely represents selected embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art on the basis of the embodiments of the present disclosure without making inventive efforts also fall into the protection scope of the present disclosure.

[0025] Unless otherwise defined in the context, a singular form includes its plural form. Throughout the description, terms like “comprise”, “provided with”, etc., are used to specify the existence of said characteristic, number, step, operation, component, portion, or a combination thereof, without excluding the existence or addition of one or more other characteristics, numbers, steps, operations, components, portions, or a combination thereof.

[0026] In addition, even if terms including “first”, “second”, and other ordinal numbers may be used to describe each component, these components are not limited by these terms, and such a term is used only to differentiate an element from another element. For example, without departing from the scope of the present disclosure, a first component may be referred to as a second component and, similarly, a second component may be referred to as a first component.

[0027] It should be understood that in the description of the present invention, a directional or positional relationship indicated by terms like “upper”, “lower”, “left”, “right”, “inner”, “outer”, etc., is based on a directional or positional relationship shown in the drawing, or is a directional or positional relationship in which the disclosed product is usually placed when used, or is a directional or positional relationship usually understood by those skilled in the art; it is intended only for convenience of description of the present disclosure and brevity of description, instead of indicating or implying that the device or component in question must have a specific direction or be structured or operated in a specific direction, and therefore should not be construed as limiting the present disclosure.

[0028] The present invention relates to an electric drive assembly system 10, which is applicable to an electric vehicle or hybrid vehicle, for example, and typically comprises an inverter (not shown), a motor assembly 200, and a gearbox assembly 300, wherein the inverter is connected to the motor assembly 200 and provides the required electrical energy to the motor assembly 200, the electrical energy is converted into mechanical energy inside the motor assembly 200, the motor assembly 200 transfers the mechanical energy to the gearbox assembly 300, and the gearbox assembly 300 typically transmits the mechanical energy to, for example, a wheel of the vehicle, through its differential to drive the wheel to move.

[0029] Specifically, as shown in Fig. 1, the electric drive assembly system 10 proposed by the present invention comprises a housing 100, in which a motor assembly 200, a gearbox assembly 300, and a support structure for supporting the motor assembly 200 and the gearbox assembly 300 are accommodated. In a specific embodiment, the interior of the housing 100 is may be divided into a first portion for accommodating the motor assembly 200 and a second portion for accommodating the gearbox assembly 300. In some embodiments, as shown in Fig. 1, the housing 100 may be configured to comprise a single body shared by the motor assembly 200 and the gearbox assembly 300, which reduces the number of components and simplifies the assembly process to achieve a lighter housing and higher compactness. In some other embodiments (not shown), the housing 100 may be configured to comprise a first housing for accommodating the motor assembly 200 and a second housing for accommodating the gearbox assembly 300, wherein the first housing and the second housing are manufactured separately and may be assembled together, which facilitates modular manufacturing and allows for more flexible designs of the motor assembly 200 and the gearbox assembly 300.

[0030] As shown in Fig. 1, the motor assembly 200 comprises a motor shaft 210 that can rotate around rotation axis X, and comprises a first motor shaft end 211 and a second motor shaft end 212 that are axially opposite each other. The first motor shaft end 211 can be supported by the first bearings 400. In a specific embodiment, the first bearings 400 may be positioned in a first bearing seat provided on the housing 100, and, more specifically, may be provided in the housing 100.

[0031] As shown in Fig. 1, the gearbox assembly 300 comprises an input shaft 310, and the input shaft 310 comprises a first input shaft end 311 and a second input shaft end 312 that are axially opposite each other. The second input shaft end 312 can be supported by the second bearings 500. In a specific embodiment, the second bearings 500 may be positioned in a second bearing seat 530 provided on the housing 100, and the second bearing seat 530 may more specifically be provided in an end cover of the housing 100, which is beneficial for ensuring overall compactness and system stability.

[0032] As shown in Fig. 1, in the electric drive assembly system 10 proposed according to the present invention, the first input shaft end 311 may be inserted into the second motor shaft end 212 and forms a coupling portion with the second motor shaft end 212, so that the input shaft 310 and the motor shaft 210 can rotate coaxially together, that is, so that the input shaft 310 can also rotate around the rotation axis X. In an embodiment, the coupling portion may comprise a spline coupling part S and a radial centring part C, wherein the spline coupling portion S is configured to achieve torque transmission from the motor shaft 210 to the input shaft 310, while the radial centring part C is configured to ensure the radial centralisation of the motor shaft 210 and the input shaft 310 relative to each other. More specifically, third bearings 600 may also be provided, which are supported at the second motor shaft end 212 and are, for example, located in a third bearing seat 630 provided in the housing 100. The third bearings 600 can more specifically support the second motor shaft end 212 at the coupling portion, thereby simultaneously supporting the motor shaft 210 and the input shaft 310. More specifically, in this case, the third bearings 600 may be arranged to be supported, at the radial centring part C, on the second motor shaft end 212.

[0033] Therefore, in the electric drive assembly system 10 proposed in the present disclosure, the coupling portion formed by the motor shaft 210 of the motor assembly 200 and the input shaft 310 of the gearbox assembly 300 comprises a spline coupling part S and a radial centring part C, which ensures good centralisation of the motor shaft 210 and the input shaft 310 relative to each other while allowing torque transmission between the motor shaft 210 and the input shaft 310, effectively avoiding vibration and noise caused by radial eccentricity between the motor shaft 210 and the input shaft 310, and thus ensuring efficient and stable torque transmission from the motor shaft 210 to the input shaft 310 of the gearbox assembly 300. Further, the use of the first bearings 400, second bearings 500, and third bearings 600 as defined above helps to provide strong and stable support for the motor shaft 210 and input shaft 310 and thus for the motor assembly 200 and the gearbox assembly 300 by means of a compact structure. Specifically, the layout of these three groups of bearings and the positioning of the coupling portion relative thereto and to the motor shaft 210 and input shaft 310 allow for particularly stable support of the input shaft 310 of the gearbox assembly 300 and the motor shaft 210, further reducing vibration and noise, allow for a microscopic shaping design of the teeth of the gears of the gearbox assembly 300 to ensure that the gears operate in the optimal state to deliver optimal performance, and further facilitate noise reduction.

[0034] In some embodiments, as shown in Fig. 1, the radial centring part C comprises a radial inner surface of the motor shaft 210 and a radial outer surface of the input shaft 310 which is in a clearance fit with the radial inner surface. Such a radial centring part C ensures good centralisation while being very easy to machine and assemble, further improving cost-effectiveness. In the specific embodiment shown in Fig. 1, the radial outer surface of the input shaft 310 formed with the radial centring part C may be formed on an annular protrusion. Thus, the radial centring part C has an easily machinable structure, which reduces design, machining, and assembly costs. Indeed, such a design of the radial centring part is only exemplary and not exclusive, and any commonly used structures that allow radial centralisation of the motor shaft and input shaft fall within the scope of protection of the present invention.

[0035] In some embodiments, as shown in Fig. 1, the radial centring part C may be arranged at the end of or near the second motor shaft end 212. This allows the third bearings 600 to be close to the gears of the gearbox assembly 300 to better support the gears, so that the gears, when subjected to stress, undergo reduced deformation and do not jolt up or down, thereby promoting stable operations of the system. In a more specific embodiment, as shown in Fig. 1, the radial centring part C and the spline coupling part S are arranged adjacent to each other in the axial direction. This configuration allows the corresponding radial centring part C and spline coupling part S to be formed easily by machining on the motor shaft 210 and input shaft 310 and is beneficial for simplifying the assembly of the motor shaft 210 and input shaft 310, thereby reducing design, manufacturing, and assembly costs and improving cost-effectiveness.

[0036] In addition, the electric drive assembly system 10 proposed by the present invention is further provided with a series of axial positioning designs to ensure that the motor shaft 210 of the motor assembly 200 and the input shaft 310 of the gearbox assembly 300 are kept in desired positions in the axial direction, so as to optimise the operational performance thereof.

[0037] In some embodiments, as shown in Fig. 1, the third bearings 600 may comprise a third bearing inner ring 610 and a third bearing outer ring 620. The second motor shaft end 212 is provided with a shoulder 213 designed to axially retain and position the third bearings 600. Further, the third bearing inner ring 610 may comprise a first axial end 611 and a second axial end 612 that are axially opposite each other, and a retaining ring 230 for axially retaining and positioning the third bearings 600 may also be provided at the second axial end 612 of the third bearing inner ring 610 and on the second motor shaft end 212. Thus, the third bearing inner ring 610 may be arranged to abut against the shoulder 213 on the second motor shaft end 212 at the first axial end 611, and to abut against the retaining ring 230 at the second axial end 612. Thus, the axial positioning and retention of the motor shaft 210 may be ensured easily and with a very compact structure, promoting stable operations of the system. In a specific embodiment, the electric drive assembly system 10 further comprises a parking ratchet wheel 330 sleeved onto the input shaft 310 of the gearbox assembly 300, the parking ratchet wheel 330 being coupled to the input shaft 310 via, for example, a spline. In this case, the retaining ring 230 may be arranged to radially press against the parking ratchet wheel 330, thereby fixing the retaining ring 230 to the second motor shaft end 212 via the parking ratchet wheel 330. More specifically, the parking ratchet wheel 330 comprises an axial extension 331 arranged around an end portion of the second motor shaft end 212, wherein the axial extension 331 is arranged to radially retain and press against the retaining ring 230, so that the retaining ring does not come off when the motor shaft and input shaft rotate at high speeds. This further ensures a compact structure while ensuring the axial positioning and retention of the motor shaft 210.

[0038] In some embodiments, as shown in Fig. 1, the housing 100 is provided with a third bearing seat 630 for accommodating the third bearings 600. In a specific embodiment, the third bearing outer ring 620 is retained axially by the third bearing seat 630, more specifically by a radial extension 631 of the third bearing seat 630, and a first pressure plate 640 fixed relative to the housing 100. This allows for the stable axial retention and positioning of the third bearings 600 with a simple and compact structure.

[0039] In some embodiments, as shown in Fig. 1, the second bearings 500 comprise a second bearing inner ring 510 and a second bearing outer ring 520, and the housing 100 may further be provided with a second bearing seat 530 for accommodating the second bearings 500. In this case, the second bearing outer ring 520 may be retained axially by the second bearing seat 530 and a second pressure plate 540 fixed relative to the housing 100. This allows for the stable axial retention and positioning of the second bearings 500 with a simple and compact structure.

[0040] In some embodiments, as shown in Fig. 1, the first bearings 400 comprise a first bearing inner ring 410 and a first bearing outer ring 420, and an elastic member (not shown) capable of applying an axial pretightening force to the first bearings 400 may also be provided between the first bearing outer ring 420 and the housing 100. The elastic member, for example, a wave spring, can apply an axial pretightening force to the first bearings 400, for example, towards the input shaft 310 of the gearbox assembly 300, so that the axial positioning of the motor shaft 210 relative to the input shaft 310 is conveniently and dynamically adjustable, thereby ensuring torque transmission efficiency, which is beneficial for improving the robustness of the overall electric drive assembly system 10.

[0041] In some embodiments, the size of the second bearings 500 is larger than the size of the first bearings 400 and the size of the third bearings 600, and the size of the third bearings 600 is larger than the size of the first bearings 400. This ensures that optimal support is provided for the motor shaft 210 and input shaft 310 in a cost-effective manner and by means of a compact configuration.

[0042] In some embodiments, the gearbox assembly 300 adopts a two-stage helical gear parallel axis arrangement, which allows for a more compact overall structure. In addition, the gearbox assembly 300 may comprise a differential, which, for example, may be coupled to a wheel of a vehicle and thus transmit torque to the wheel.

[0043] The present invention further relates to a vehicle comprising an electric drive assembly system as described above. The vehicle may be an electrified vehicle, for example, a battery electric vehicle (BEV), a hybrid electric vehicle (HEV), a plugin hybrid electric vehicle (PHEV), a range-extended EV, or a fuel cell electric vehicle (FCEV). The vehicle may also be a hydrogen-powered vehicle.

[0044] While exemplary implementations of an electric drive assembly system proposed by the present invention have been described in detail above with reference to preferred embodiments, those skilled in the art can understand that various modifications and variations may be made to the specific embodiments without departing from the concept of the present invention, and that various combinations of the technical features and structures proposed by the present invention may be made without exceeding the scope of protection of the present invention.

[0045] The scope of the present disclosure, rather than being limited by the embodiments described above, is defined by the appended claims and scopes equivalent thereto.

Claims

WHAT IS CLAIMED IS:

1. An electric drive assembly system, comprising a housing (100) and the following located in the housing (100): a motor assembly (200), comprising a motor shaft (210), the motor shaft (210) comprising a first motor shaft end (211) and a second motor shaft end (212), a gearbox assembly (300), comprising an input shaft (310), the input shaft (310) comprising a first input shaft end (311) and a second input shaft end (312), the first input shaft end (311) being inserted into the second motor shaft end (212) and forming a coupling portion with the second motor shaft end (212), so that the input shaft (310) and the motor shaft (210) rotate coaxially together, first bearings (400), supported at the first motor shaft end (211), and second bearings (500), supported at the second input shaft end (312), wherein the coupling portion comprises a spline coupling part (S) and a radial centring part (C), and the electric drive assembly system further comprises third bearings (600), the third bearings (600) being supported, at the radial centring part (C), on the second motor shaft end (212).

2. The electric drive assembly system according to Claim 1, wherein the radial centring part (C) comprises a radial inner surface of the motor shaft (210) and a radial outer surface of the input shaft (310) which is in a clearance fit with the radial inner surface.

3. The electric drive assembly system according to Claim 1 or 2, wherein the radial centring part (C) is arranged at the end of the second motor shaft end (212).

4. The electric drive assembly system according to Claim 1 or 2, wherein the third bearings (600) comprise a third bearing inner ring (610) and a third bearing outer ring (620), the second motor shaft end (212) is provided with a shoulder (213), a retaining ring (230) is provided at a second axial end (612) of the third bearing inner ring (610) and on the second motor shaft end (212), andthe third bearing inner ring (610) abuts against the shoulder (213) at a first axial end (611) and abuts against the retaining ring (230) at the second axial end (612).

5. The electric drive assembly system according to Claim 4, further comprising a parking ratchet wheel (330) sleeved onto the input shaft (310), wherein the retaining ring (230) radially presses against the parking ratchet wheel (330).

6. The electric drive assembly system according to Claim 4, wherein the housing (100) is provided with a third bearing seat (630) for accommodating the third bearings (600), and the third bearing outer ring (620) is retained axially by the third bearing seat (630) and a first pressure plate (640) fixed relative to the housing (100).

7. The electric drive assembly system according to Claim 1 or 2, wherein the first bearings (400) comprise a first bearing inner ring (410) and a first bearing outer ring (420), and an elastic member capable of applying an axial pretightening force to the first bearings (400) is provided between the first bearing outer ring (420) and the housing (100).

8. The electric drive assembly system according to Claim 1 or 2, wherein the second bearings (500) comprise a second bearing inner ring (510) and a second bearing outer ring (520), the housing (100) is further provided with a second bearing seat (530) for accommodating the second bearings (500), and the second bearing outer ring (520) is retained axially by the second bearing seat (530) and a second pressure plate (540) fixed relative to the housing (100).

9. The electric drive assembly system according to Claim 1 or 2, wherein the size of the second bearings (500) is larger than the size of the first bearings (400) and the size of the third bearings (600), and the size of the third bearings (600) is larger than the size of the first bearings (400).

10. The electric drive assembly system according to Claim 1 or 2, wherein the gearbox assembly (300) adopts a two-stage helical gear parallel axis arrangement and comprises a differential.

11. A vehicle comprising an electric drive assembly system (10) according to any one of Claims 1 to 10.

Images