EP4222844A1

EP4222844A1 - Electric drive assembly system and vehicle

Info

Publication number: EP4222844A1
Application number: EP21794738.1A
Authority: EP
Inventors: Zhenyu Zhao; Wenhui Wang; Long HAN; Rupeng CHEN
Original assignee: Valeo Automotive ePowertrain Systems Shanghai Co Ltd
Current assignee: Valeo Automotive ePowertrain Systems Shanghai Co Ltd
Priority date: 2020-09-30
Filing date: 2021-09-28
Publication date: 2023-08-09
Also published as: WO2022068821A1; MX2023003717A; CN112498077A

Abstract

An electric drive assembly system and a vehicle are disclosed, and the electric drive assembly system includes: a housing including a body and a first end cover mated with the body; a rotor shaft having a rotational axis and a first end near to the first end cover along the rotational axis and a second end opposite to the first end; and a pinion input shaft coaxially disposed with the rotor shaft and having a first end portion near to the first end cover along the rotational axis and a second end portion opposite to the first end portion, the pinion input shaft is received in a pinion housing space formed by the first end cover and another part of the body; wherein the housing is a common housing shared by the motor and the pinion input shaft, wherein the electric drive assembly system further includes a first bearing, a second bearing and a third bearing.

Description

ELECTRIC DRIVE ASSEMBLY SYSTEM AND VEHICLE

CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of the Chinese Patent Application No. 202011065310.3 filed on September 30, 2020 and the Chinese Patent Application No. 202011479185.0 filed on December 15, 2020, the entire disclosure of which is incorporated herein by reference in their entirety.

TECHNICAL FIELD

The embodiments of the present disclosure relate to an electric drive assembly system and a vehicle including the electric drive assembly system.

BACKGROUND

In the current market, the motor, inverter and reducer of electric drive systems are usually manufactured separately. Motor, reducer and inverter are connected to each other via fasteners. Since the housings of the reducer and the motor are separated, the signal connection and cooling water flow between the inverter and the motor require separate connectors and water pipes.
Meanwhile, this electric drive system has a large volume and a large size. The existing integration method of the electric drive system occupies a large space in the overall layout of the vehicle, and therefore brings the following difficulties: the total cost is relatively high, and it lacks market competitiveness.
SUMMARY
In view of the above-mentioned problems and needs, the present invention proposes an electric drive assembly system and a vehicle including the electric drive assembly system, which can solve the above technical problems due to the following technical solutions and has other technical advantages.
According to one aspect of the present invention, an electric drive assembly system is proposed, which includes: a housing including a body and a first end cover mated with the body; a rotor shaft having a rotational axis and a first end near to the first end cover along the rotational axis and a second end opposite to the first end, the rotor shaft at least partially received in a motor housing space formed by a part of the body, and the rotor shaft rotationally fixed to the rotor of the motor; and a pinion input shaft coaxially disposed with the rotor shaft and having a first end portion near to the first end cover along the rotational axis and a second end portion opposite to the first end portion, the pinion input shaft received in a pinion housing space formed by the first end cover and another part of the body, and the pinion input shaft rotationally fixed to the rotor shaft. The housing is a common housing shared by the motor and the pinion input shaft, the first end of the rotor shaft extends toward the pinion housing space and is located in a shaft hole of the pinion input shaft. The electric drive assembly system further includes a first bearing supporting the pinion input shaft at the first end portion; a second bearing supporting the rotor shaft at the second end; a third bearing supporting the pinion input shaft at the second end portion and installed in the body.
With the above features, only three bearings are needed to support the rotor shaft and the pinion input shaft. The common housing of the motor and the pinion input shaft can reduce one housing part, and correspondingly reduces one set of die-casting abrasive tools. In addition, the weight and overall size of the electric drive assembly system can be reduced, which is more conducive to its spatial arrangement in the vehicle and makes it more competitive in the market. For example, the length of the electric drive assembly system along the rotational axis can be reduced by 15-20mm.
In some examples, the first bearing is installed in the first end cover.
In some examples, the housing further includes a second end cover mated with the body, the second end cover is arranged opposite to the first end cover, and the second bearing is installed in the second end cover.
With the above features, the two bearings can be respectively installed in the bearing mounting holes integrally formed in the first end cover and the second end cover, compared with separately providing a bearing seat with a bearing hole and then connecting the bearing seat to the housing, it is easier to simplify the structure, and is more conducive to ensuring the machining accuracy of the bearing hole.
In some examples, the rotor shaft is splined with the pinion input shaft.
With the above features, the rotor shaft and the pinion input shaft can be rotationally fixed in the circumferential direction reliably through splines.
In some examples, the rotor shaft is in clearance fit with the shaft hole at the second end portion.
With the above features, a fit clearance between the longer rotor shaft and the shaft hole of the pinion input shaft is provided, which helps to improve the fit reliability between the rotor shaft and the pinion input shaft.
In some examples, a seal extending in the circumferential direction is provided between the rotor shaft and the pinion input shaft at the second end portion.
In some examples, the electric drive assembly system further includes a mounting member with a cylindrical body and a flange, the cylindrical body is mounted to the first end by bolts, and the flange axially abuts against the first end portion.
In some examples, a seal extending in the circumferential direction is provided between the mounting member and the pinion input shaft at the first end portion.
An effective seal between the lubricant in the shaft hole and the outside can be ensure with the seals at the first end portion and the second end portion.
In some examples, the seal is an O-ring seal.
In some examples, a lip-type seal extending in the circumferential direction is provided between the rotor shaft and the body and adjacent to the third bearing.
In some examples, at least one of the first bearing, the second bearing, and the third bearing is a deep groove ball bearing.
With the above features, the use of deep groove ball bearings can reduce the cost while ensuring the reliability of the support.
In some examples, the electric drive assembly system further includes a reducer layout of two-stage helical gear parallel shaft.
In some examples, the electric drive assembly system is provided with a differential that is provided in the pinion housing space and is coupled to the reducer layout.
In some examples, the reducer layout and differential are provided with deep groove ball bearings.
In some examples, the electric drive assembly system further includes an inverter housing, and the inverter housing is fixed to the housing.
According to another aspect of the present invention, a vehicle is provided, which includes the electric drive assembly system as described above.
In summary, the electric drive assembly system proposed by the present invention only needs three bearings to support the rotor shaft and the pinion input shaft. The common housing of the motor and the pinion input shaft can reduce one housing part, and reduce one set of die-casting abrasive tools correspondingly. In addition, the weight and overall size of the electric drive assembly system can be reduced, which is more conducive to its spatial arrangement in the vehicle and makes it more competitive in the market. Since the vehicle proposed by the present invention has the above-mentioned electric drive assembly system, it also has the same advantages and benefits.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to explain the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings of the embodiments of the present invention will be briefly introduced below. Among them, the drawings are only used to show some embodiments of the present invention, instead of limiting all the embodiments thereof to these.
Fig. 1 is a front view of an electric drive assembly system according to an exemplary embodiment of the present invention;
Fig. 2 is a cross-sectional view of an electric drive assembly system according to an exemplary embodiment of the present invention;
Fig. 3 shows a partial enlarged view of the clearance fit between the rotor shaft and the shaft hole in Fig. 2.
Reference numerals
1 Housing
11 Body
12 First end cover
13 Second end cover
2 Rotor shaft
21 First end
22 Second end
3 Pinion input shaft
31 First end portion
32 Second end portion
4 First bearing
5 Second bearing
6 Third bearing
71, 72 Seal
8 Mounting member
9 Lip-type seal
101 Input gear
102 Intermediate first gear
103 Intermediate second gear
104 Intermediate shaft
20 Differential
100 Motor
110 Rotor
120 Stator
200 Reducer
300 Inverter
301 Inverter housing
M Motor housing space
G Pinion housing space
A Rotational axis

DETAILED DESCRIPTION

In order to make the objectives and advantages of the technical solutions of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be described clearly and completely in conjunction with the accompanying drawings of specific embodiments of the present disclosure. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are just a part but not all of the embodiments of the present disclosure. Based on the described embodiments herein, those skilled in the art can obtain other embodiment (s) , without any inventive work, which should be within the scope of the present disclosure.
Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings commonly understood by those with ordinary skills in the art to which the present disclosure belongs. The terms “first, ” “second, ” etc., which are used in the description and the claims of the present disclosure, are not intended to indicate any sequence, amount or importance, but distinguish various components. Similarly, similar terms such as "a" or "an" do not necessarily indicate quantitative restrictions. The terms "include" or "comprise" and other similar words mean that the element or item appearing before the word encompasses the element or item listed after the word and its equivalents, but does not preclude other elements or items. Similar terms such as "connect" or "connected with" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms "up" , "down" , "left" , "right" , etc. are only used to indicate the relative position relationship, and when the absolute position of the described object changes, the relative position relationship may also change accordingly.
Electrification has become one of the important development directions of the automobile industry. As the power system of electric vehicles, the electric drive assembly system is focused on its integration, light weight, and reliability.
The electric drive assembly system is a highly integrated electric drive system, which is usually composed of a permanent magnet synchronous motor, an inverter and a reducer. In the current market, the motor, inverter, and reducer of the electric drive system are usually manufactured separately, the motor, reducer, and inverter are connected to each other via fasteners. This separate arrangement makes the electric drive assembly system larger in volume and size, heavier in weight, and occupies a lot of space in the overall layout of the vehicle.
Based on the above problems, the present invention proposes an electric drive assembly system and a vehicle including the electric drive assembly system, especially an electric vehicle.
Fig. 1 is a front view of an electric drive assembly system according to an exemplary embodiment of the present invention. Fig. 2 is a cross-sectional view of an electric drive assembly system according to an exemplary embodiment of the present invention.
As shown in Fig. 1, the electric drive assembly system may include a motor 100, a reducer 200 and an inverter 300. The inverter 300 converts direct current (for example a battery, a storage battery) into a constant frequency and constant voltage or a frequency and voltage regulation alternating current to be input to the motor 100. The motor 100 is, for example, a permanent magnet synchronous motor or an AC asynchronous motor. The motor 100 is connected to the reducer 200 in transmission, so that the torque of the motor 100 is decelerated by the reducer 200 and output.
The motor 100 may include a rotor 110 and a stator 120. The arrangement of the rotor 110 and the stator 120 is a common method in the art, which will not be described in detail in the present disclosure.
Fig. 2 shows a cross-sectional view of an electric drive assembly system according to an exemplary embodiment of the present invention, and Fig. 2 further details the structure diagram of the electric drive assembly system. As shown in Fig. 2, the electric drive assembly system further includes: a housing 1, a rotor shaft 2, a pinion input shaft 3, a first bearing 4, a second bearing 5 and a third bearing 6.
The housing 1 includes a body 11 and a first end cover 12 mated with the body 11.Moreover, the housing 1 may further include a second end cover 13 mated with the body 11, and the second end cover 13 is disposed opposite to the first end cover 12. Specifically, the first end cover 12 and the second end cover 13 are oppositely disposed at two ends of the body 11, and can be installed to the body 11 by fasteners, such as bolts. Optionally, the first end cover 12 and the second end cover 13 may also be welded to the body 11 after assembly.
A part of the body 11 forms a motor housing space M, and another part of the body 11 and the first end cover 12 form a pinion housing space G. Specifically, the motor housing space M is defined by a part of the body 11, and the second end cover 13 closes the motor housing space M. Another part of the body 11 and the first end cover 12 enclose a pinion housing space G, that is, a part of the pinion housing space G is provided by the body 11 and the other part is provided by the first end cover 12.
Therefore, compared with the manner that the motor and the reducer are arranged separately, the housing 1 and the first end cover 12 provided by the present invention can save a housing part, and therefore reduce the die-casting mold for processing the housing part. In addition, the arrangement of the shared housing of the motor and the reducer can also obtain a more compact and light-weight electric drive assembly arrangement, which can actually reduce the length (in the direction of the rotational axis A of the rotor shaft 2) by 15-20mm.
The rotor shaft 2 is rotationally fixed to the rotor 110 of the motor 100. The rotor shaft 2 has a rotational axis A, and has a first end 21 near to the first end cover 12 along the rotational axis A and a second end 22 opposite to the first end 21. The rotor shaft 2 is at least partially received in the motor housing space M, and the other part is received in the pinion housing space G.
It should be noted that “rotationally fixed” mentioned herein refers to that two components are connected in a manner that they can rotate together, and their mutual movement in the direction of rotation (for example, the circumferential direction) is restricted so as to be able to rotate together. "Rotationally fixed" does not limit the displacement along the direction of the rotational axis A, therefore, the two components that are rotationally fixed together can be relatively displaced along the direction of the rotational axis A. If the displacement in the direction of the rotational axis A is also fixed, it can be considered that the two components are completely fixedly connected.
Further, the first end 21 of the rotor shaft 2 is supported by the first end cover 12, the second end 22 of the rotor shaft 2 is supported by the second end cover 13, and the middle part of the rotor shaft 2 between the first end 21 and the second end 22 is supported by the body 11. The middle part is located at the edge of the pinion housing space G adjacent to the motor housing space M. Specifically, the support of the rotor shaft 2 is realized by the first bearing 4, the second bearing 5 and the third bearing 6 respectively, which will be described in detail below.
The pinion input shaft 3 is coaxially disposed with the rotor shaft 2 and has a first end portion 31 near to the first end cover 12 along the rotational axis A and a second end portion 32 opposite to the first end portion 31. The pinion input shaft 3 is received in the pinion housing space G formed by the first end cover 12 and another part of the body 11, and the pinion input shaft 3 is rotationally fixed to the rotor shaft 2.
Specifically, the first end 21 of the rotor shaft 2 extends toward the pinion housing space G and is located in a shaft hole of the pinion input shaft 3. Optionally, the rotor shaft 2 is splined with the pinion input shaft 3. For example, the rotor shaft 2 has an external spline, and the pinion input shaft 3 has an internal spline that cooperates with the external spline. The present invention is not limited to this, and those skilled in the art can also use other common shaft coupling methods, such as bonding, riveting, and bolting.
In this embodiment, the housing 1 is a common housing shared by the motor 100 and the pinion input shaft 3. Further, the housing 1 is a common housing shared by the motor 100 and the reducer 200.
In this embodiment, the first bearing 4 supports the pinion input shaft 3 at the first end portion 31 so as to indirectly support the rotor shaft 2. The second bearing 5 supports the rotor shaft 2 at the second end 22. The third bearing 6 supports the pinion input shaft 3 at the second end portion 32 and is installed in the body 11.
Specifically, the first bearing 4 is installed in the first end cover 12, and the second bearing 5 is installed in the second end cover 13. The first end cover 12 and the second end cover 13 can be integrated to form a bearing mounting hole for mounting the bearing. Compared with separately providing a bearing seat with a bearing hole and then connecting the bearing seat to the housing, it is easier to simplify the structure, and is more conducive to ensuring the machining accuracy of the bearing hole.
The rotor shaft 2 is in clearance fit with the shaft hole at the second end portion 32. Fig. 3 shows a partial enlarged view of the clearance fit between the rotor shaft 2 and the shaft hole in Fig. 2 and specifically shows this clearance fit.
As can be seen from Fig. 3, at the second end portion 32, there is a gap between the rotor shaft 2 and the pinion input shaft 3, and a seal 72 extending in the circumferential direction is provided between the rotor shaft 2 and the pinion input shaft 3 at the second end portion 32 to seal the gap.
Optionally, the electric drive assembly system may further include a mounting member 8 having a cylindrical body and a flange, the cylindrical body is mounted to the first end by bolts, and the flange abuts axially against the first end 31.
Similarly, a seal 71 extending in the circumferential direction is provided between the pinion input shaft 3 and the mounting member 8 at the first end portion 31.
Optionally, both the seals 71 and 72 may be O-ring seals.
Exemplarily, a lip-type seal 9 extending in the circumferential direction is provided between the rotor shaft 2 and the body and adjacent to the third bearing 6, and the lip-type seal 9 is a bidirectional seal.
Exemplarily, at least one of the first bearing 4, the second bearing 5, and the third bearing 6 is a deep groove ball bearing. In this embodiment, the first bearing 4, the second bearing 5 and the third bearing 6 are all deep groove ball bearings.
Exemplarily, the electric drive assembly system may also include a reducer layout of two-stage helical gear parallel shaft. The electric drive assembly system is provided with a differential 20 provided in the pinion housing space G and is coupled to the reducer layout 10. Fig. 2 shows a reducer layout of two-stage helical gear parallel shaft in an exemplary and non-limiting manner.
The reducer layout may include an input gear 101, an intermediate first gear 102 and an intermediate second gear 103. The input gear 101 is fixedly coupled to the pinion input shaft 3, for example, may be integrally formed with the pinion input shaft 3 or connected by splines. The intermediate first gear 102 and the intermediate second gear 103 are sequentially arranged on the intermediate shaft 104. The intermediate shaft 104 is arranged in parallel with the pinion input shaft 3, and the intermediate shaft 104 may be a hollow shaft. The sizes of the input gear 101, the intermediate first gear 102, and the intermediate second gear 103 can be selected according to actual requirements. The first intermediate gear 102 is drivingly meshed with the input gear 101, and the second intermediate gear 103 may be fixed to the differential 20 by bolts. This exemplarily realizes the reducer layout of two-stage helical gear parallel shaft from the pinion input shaft 3 to the differential 20.
Optionally, the reducer layout 10 and the differential 20 are provided with deep groove ball bearings. For example, the two ends of the intermediate shaft 104 and the two ends of the differential 20 can be supported by deep groove ball bearings, respectively. Half of the deep groove ball bearings are installed in the first end cover 12, and the other half of the deep groove ball bearings are installed in the body 11.
Optionally, the electric drive assembly system may also include a cooling and heat exchange system. The cooling and heat exchange system is, for example, a circulating water cooling system, which is arranged in the motor housing space M, and cools the stator of the motor 100 by means of water cooling. The cooling and heat exchange system may further include heat sinks for enhancing heat dissipation, which may be integrally formed with the second end cover 13 or fixedly connected to the second end cover 13.
In addition, the electric drive assembly system may further include an inverter housing 301, and the inverter housing 301 is fixed to the housing 1. In summary, the connection and arrangement between the motor 100, the reducer 200 and the inverter 300 are thus formed.
According to another aspect of the present invention, a vehicle is provided , which includes the electric drive assembly system as described above. In particular, the vehicle may be an electric vehicle.
In summary, the electric drive assembly system proposed by the present invention only needs three bearings to support the rotor shaft and the pinion input shaft. The common housing of the motor and the pinion input shaft can reduce one housing part, and reduce one set of die-casting abrasive tools correspondingly. In addition, the weight and overall size of the electric drive assembly system can be reduced, which is more conducive to its spatial arrangement in the vehicle and makes it more competitive in the market. Since the vehicle proposed by the present invention has the above-mentioned electric drive assembly system, it also has the same advantages and benefits.
The above are merely specific implementation manners of the present disclosure, but the protection scope of the embodiments of the present disclosure is not limited thereto. Any changes, alternatives and combinations that a person skilled in the art could readily conceive of within the technical scope disclosed in the embodiments of the present disclosure or under the ideas disclosed in the embodiments of the present disclosure shall be included in the protection scope of the embodiments of the present disclosure. Therefore, the scope of the disclosure is determined by the appended claims.

Claims

An electric drive assembly system comprising:

a housing comprising a body and a first end cover mated with the body;

a rotor shaft having a rotational axis and having a first end near to the first end cover along the rotational axis and a second end opposite to the first end, said rotor shaft at least partially received in a motor housing space formed by a part of the body, said rotor shaft rotationally fixed to a rotor of the motor; and

a pinion input shaft coaxially disposed with the rotor shaft and having a first end portion near to the first end cover along the rotational axis and a second end portion opposite to the first end portion, said pinion input shaft received in a pinion housing space formed by the first end cover and another part of the body, said pinion input shaft rotationally fixed to the rotor shaft;

wherein the housing is a common housing shared by the motor and the pinion input shaft,

wherein the first end of the rotor shaft extends toward the pinion housing space and is located in a shaft hole of the pinion input shaft,

wherein the electric drive assembly system further comprises:

a first bearing supporting the pinion input shaft at the first end portion;

a second bearing supporting the rotor shaft at the second end; and

a third bearing supporting the pinion input shaft at the second end portion and installed in the body.
The electric drive assembly system according to claim 1, wherein the first bearing is installed in the first end cover.
The electric drive assembly system according to claim 2, wherein the housing further includes a second end cover mated with the body, the second end cover is arranged opposite to the first end cover, and the second bearing is installed in the second end cover.
The electric drive assembly system according to claim 1, wherein the rotor shaft is splined with the pinion input shaft.
The electric drive assembly system according to claim 1 or 4, wherein the rotor shaft is in clearance fit with the shaft hole at the second end portion.
The electric drive assembly system according to claim 5, wherein a seal extending in a circumferential direction is provided between the rotor shaft and the pinion input shaft at the second end portion.
The electric drive assembly system according to claim 1, further comprising a mounting member having a cylindrical body and a flange, wherein the cylindrical body is mounted to the first end by bolts, and the flange axially abuts against the first end portion.
The electric drive assembly system according to claim 7, wherein a seal extending in a circumferential direction is provided between the mounting member and the pinion input shaft at the first end portion.
The electric drive assembly system according to claim 6 or 8, wherein the seal is an O-ring seal.
The electric drive assembly system according to claim 1, wherein a lip-type seal extending in the circumferential direction is provided between the rotor shaft and the body and adjacent to the third bearing.
The electric drive assembly system according to claim 1, wherein at least one of the first bearing, the second bearing, and the third bearing is a deep groove ball bearing.
The electric drive assembly system according to claim 1, further comprising: a reducer layout of two-stage helical gear parallel shaft.
The electric drive assembly system according to claim 12, wherein the electric drive assembly system is provided with a differential, which is disposed in the pinion housing space and is coupled to the reducer layout.
The electric drive assembly system according to claim 13, wherein the reducer layout and differential are provided with deep groove ball bearings.
The electric drive assembly system according to claim 1, further comprising an inverter housing fixed to the housing.
A vehicle comprising the electric drive assembly system according to any one of claims 1 to 15.