CN112193044A

CN112193044A - Electric drive assembly system and vehicle

Info

Publication number: CN112193044A
Application number: CN202011061297.4A
Authority: CN
Inventors: 王文辉; 韩龙; 赵振宇; 赵婧婧
Original assignee: Siemens Electric Vehicle Powertrain System Shanghai Co ltd
Current assignee: Siemens Electric Vehicle Powertrain System Shanghai Co ltd
Priority date: 2020-09-30
Filing date: 2020-09-30
Publication date: 2021-01-08
Also published as: WO2022068822A1

Abstract

The present invention relates to an electric drive assembly system comprising: the shell comprises a main body, a first end cover and a second end cover, wherein the first end cover and the second end cover are arranged at two opposite ends of the main body; the speed reducer assembly is positioned in a first accommodating space formed by the main body and the first end cover in a surrounding mode; and a rotor shaft having a rotation axis and having a first end portion adjacent to the first end cover along the rotation axis and a second end portion opposite to the first end portion, the rotor shaft being rotationally fixed to a rotor of the motor, the rotor being accommodated in a second accommodation space surrounded by the main body and the second end cover; wherein the housing is a housing common to the motor and the speed reducer assembly, wherein the electric drive assembly system further comprises: a first bearing, a second bearing and a third bearing.

Description

Electric drive assembly system and vehicle

Technical Field

The invention relates to an electric drive assembly system and a vehicle comprising the same.

Background

In the current market, the motor, inverter and reducer of the electric drive system are usually manufactured separately. The motor, the reducer, and the inverter are connected to each other by fasteners. Since the housings of the motor and the decelerator are separated, signal connection and cooling water flow between the inverter and the motor require separate connectors and water pipes.

Meanwhile, the electric drive system is large in size and size. The existing integration methods of electric drive systems take up a lot of space in the overall layout of the vehicle, thus presenting the following difficulties: the total cost is relatively high and the market competitiveness is lacking.

Disclosure of Invention

The present invention addresses the above-mentioned problems and needs, and provides an electric drive assembly system and a vehicle including the same, which are capable of solving the above-mentioned problems and having other technical advantages due to the following technical solutions.

According to one aspect of the present disclosure, an electric drive assembly system is provided, including a housing including a main body, a first end cap and a second end cap, the first end cap and the second end cap being disposed at opposite ends of the main body; the speed reducer assembly is positioned in a first accommodating space formed by the main body and the first end cover in a surrounding mode; and a rotor shaft having a rotation axis and having a first end portion adjacent to the first end cover along the rotation axis and a second end portion opposite to the first end portion, the rotor shaft being rotationally fixed to a rotor of the motor, the rotor being accommodated in a second accommodation space surrounded by the main body and the second end cover. The input gear of the speed reducer assembly is integrally formed on the rotor shaft, the input gear and the rotor shaft are coaxially arranged, and the shell is a shell shared by the motor and the speed reducer assembly.

The electric drive assembly system further includes a first bearing supporting the rotor shaft at a first end; a second bearing supporting the rotor shaft at a second end; and a third bearing supporting the rotor shaft between the rotor and the input gear and mounted within the body. The rotor shaft forms a shoulder between the third bearing and the rotor against which the third bearing abuts, the rotor shaft having a radial dimension between the shoulder to the first end that is less than an inner race diameter of the third bearing.

According to the characteristics, the output shaft of the motor and the input shaft of the speed reducer assembly form an integral shaft, the torque between the motor and the speed reducer assembly is directly transmitted, the bearing span is reduced, the physical joint is eliminated, and the potential risks of abrasion and faults existing in long-term operation are avoided.

The common housing of the electric motor and the gear input shaft can reduce a housing part, and accordingly, a set of die-casting grinding tools can be reduced, so that the weight and the overall size of the electric drive assembly system can be reduced, the spatial arrangement of the electric drive assembly system in a vehicle can be facilitated, and the electric drive assembly system is more competitive in the market. For example, the length of the electric drive assembly system along the axis of rotation may be reduced by 15-20 mm.

In addition, the radial dimension of the rotor shaft between the shaft shoulder and the first end part is designed to be smaller than the diameter of the inner ring of the third bearing, so that the rotor shaft is convenient to assemble and disassemble.

In some examples, the first bearing is mounted within a first end cap and the second bearing is mounted within a second end cap.

Through above-mentioned characteristic, two bearings can install respectively in the bearing mounting hole of an organic whole in first end cover and second end cover, compare in set up alone and set up the bearing frame of seting up the dead eye and again be connected to this bearing frame to the casing, the simplification of the structure of being more convenient for, and more do benefit to the machining precision who guarantees the dead eye.

In some examples, the rotor shaft is further provided with a snap ring abutting a side of the third bearing opposite the shoulder.

Through the characteristics, the rotor shaft is provided with the clamping ring, so that the axial position of the third bearing can be conveniently fixed.

In some examples, a circumferentially extending lip seal is disposed between the rotor shaft and the main body and adjacent the third bearing, the lip seal being disposed on a side of the third bearing opposite the snap ring.

In some examples, a shaft bore extending along an axis of rotation within the rotor shaft is provided at the first end.

In some examples, the shaft bore extends beyond the shoulder along the axis of rotation.

Through setting up the shaft hole, can alleviate the weight of rotor shaft when guaranteeing bulk strength.

In some examples, at least one of the first bearing, the second bearing, and the third bearing is a deep groove ball bearing.

Through the characteristics, the deep groove ball bearing is adopted, so that the supporting reliability is ensured, and meanwhile, the cost is reduced.

In some examples, the reducer assembly is a two-stage helical gear parallel shaft reducer arrangement.

In some examples, the electric drive assembly system is provided with a differential disposed within the first housing space and coupled to the speed reducer arrangement.

In some examples, the retarder arrangement and differential are provided with deep groove ball bearings.

In some examples, the electric drive assembly system further includes an inverter housing secured to the electric machine housing.

According to another aspect of the present invention, a vehicle is provided, comprising an electric drive assembly system as described above.

In summary, the electric drive assembly system of the present invention forms the output shaft of the motor and the input shaft of the reducer assembly as an integral shaft, directly transmits the torque between the motor and the reducer assembly, reduces the bearing span, and eliminates the physical joints. The common housing of the motor and the gear input shaft allows a reduction in one housing part and a corresponding reduction in a die-cast grinding tool set. In addition, only three bearings are needed for supporting the rotor shaft, so that the weight and the whole size of the electric drive assembly system can be reduced, the spatial arrangement of the electric drive assembly system in a vehicle is facilitated, and the electric drive assembly system is more competitive in the market. The vehicle of the present invention also has the same advantages and benefits as the electric drive assembly system described above.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments of the present invention will be briefly described below. Wherein the drawings are only for purposes of illustrating some embodiments of the invention and are not to be construed as limiting the invention to all embodiments thereof.

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.

List of reference numerals

1 casing

11 main body

12 first end cap

13 second end cap

2 rotor shaft

21 first end part

22 second end portion

3 clasp

4 first bearing

5 second bearing

6 third bearing

7 lip seal

101 input gear

102 intermediate first gear

103 intermediate second gear

104 intermediate shaft

20 differential mechanism

100 motor

110 rotor

120 stator

200 decelerator assembly

300 inverter

301 inverter case

40 first accommodation space

50 second accommodating space

Axis of rotation A

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more clear, the embodiments of the present disclosure will be described in detail and completely with reference to the accompanying drawings of specific embodiments of the present disclosure. Like reference symbols in the various drawings indicate like elements. It should be noted that the described embodiments are only some of the embodiments of the present disclosure, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in the description and claims of the present disclosure are not intended to indicate any order, quantity, or importance, but rather are used to distinguish one element from another. Also, the use of the terms "a" or "an" and the like do not necessarily denote a limitation of quantity. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

The electric driving has become one of the important development directions in the automobile industry, and the integration level, the light weight and the reliability of the electric driving assembly system as the power system of the electric automobile are focused.

The electric drive assembly system is a highly integrated electric drive system, and generally comprises a permanent magnet synchronous motor, an inverter and a reducer component. In the current market, the motor, inverter and reducer components of the electric drive system are generally manufactured separately, interconnected by fasteners, and this separate arrangement makes the electric drive assembly system bulky and large in size, heavier, and occupies a large space in the overall layout of the vehicle.

The output shaft of the motor is connected with the input shaft of the reducer assembly through a mechanical joint, and abrasion and faults may exist in long-term operation.

In view of the above, the present invention proposes an electric drive assembly system and a vehicle, in particular an electric vehicle, comprising such an electric drive assembly system.

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 assembly 200, and an inverter 300. The inverter 300 converts direct current (e.g., a battery, a storage battery) into constant-frequency, constant-voltage or frequency-modulated and voltage-regulated alternating current to be input to the electric motor 100, and the electric motor 100 is, for example, a permanent magnet synchronous motor or an alternating current asynchronous motor. The motor 100 is drivingly connected to the reducer assembly 200, so that the torque of the motor 100 is reduced by the reducer assembly 200 and then output.

The motor 100 may include a rotor 110 and a stator 120, and the arrangement of the rotor 110 and the stator 120 is a common means in the art and is not specifically described in the present disclosure.

FIG. 2 illustrates a cross-sectional view of an electric drive assembly system of an exemplary embodiment of the present invention, with FIG. 2 further detailing the structural diagram of the electric drive assembly system. As shown in fig. 2, the electric drive assembly system further comprises: a housing 1, a rotor shaft 2, a first bearing 4, a second bearing 5 and a third bearing 6.

The housing 1 includes a main body 11, a first end cap 12 and a second end cap 13. The first and second end caps 12 and 13 are provided at opposite ends of the body 11. The first and second end caps 12 and 13 may be mounted to the body 11 by fasteners, such as bolts. Alternatively, the first and second end caps 12 and 13 may also be welded to the body 11 after assembly.

A portion of the main body 11 and the first end cap 12 enclose to form a first accommodating space 40, and another portion of the main body 11 and the second end cap enclose to form a second accommodating space 50. Specifically, a part of the first receiving space 40 is provided by the body 11, and another part is provided by the first end cap 12. The second receiving space 50 is defined by a portion of the body 11, and the second end cap 13 closes the second receiving space 50. The reducer assembly 200 is received in the first receiving space 40, and the rotor 110 of the motor 100 is received in the second receiving space 50. In addition, the stator 120 of the motor 100 may be accommodated in the second accommodation space 50.

Compared with the mode that the motor and the speed reducer are arranged separately, the shell 1 and the first end cover 12 provided by the invention can omit a shell part, thereby reducing die casting molds for machining the shell part, and in addition, the arrangement of the common shell of the motor and the speed reducer can obtain more compact and light electric drive assembly arrangement, and the length of the length direction (the direction of the rotating axis A of the rotor shaft 2) can be actually reduced by 15-20 mm.

The rotor shaft 2 is rotationally fixed to a rotor 110 of the motor 100. The rotor shaft 2 has an axis of rotation a and has a first end 21 adjacent the first end cap 12 along the axis of rotation a and a second end 22 opposite the first end 21. The rotor shaft 2 is rotationally fixed to a rotor 110 of the motor 100.

It should be noted that "rotationally fixed" as used herein means that two components are connected for common rotation, and their mutual movement in the direction of rotation (e.g. circumferential direction) is limited so as to be able to rotate together. "rotationally fixed" does not restrict displacement in the direction of the axis of rotation a, and therefore the two rotationally fixed parts can be displaced relative to each other in the direction of the axis of rotation a. If the displacement in the direction of the axis of rotation a is also fixed, the two parts can be considered to be completely fixedly connected.

The input gear 101 of the reduction gear unit 200 is integrally formed on the rotor shaft 2, and the input gear 101 is provided coaxially with the rotor shaft 2. For example, the input gear 101 may be integrally forged with the rotor shaft 2 and machined to form a tooth surface, but the present disclosure is not limited thereto, and those skilled in the art may also adopt other common integrally forming methods.

Compared with the split type motor output shaft and the split type input gear shaft which are connected through the mechanical joint, the integrally formed shaft directly transmits the torque between the motor and the speed reducer assembly, so that the bearing span is reduced, the physical joint is eliminated, and the potential risks of abrasion and faults existing in long-term operation are avoided.

Further, the first end portion 21 of the rotor shaft 2 is supported by the first end cover 12, the second end portion 22 of the rotor shaft 2 is supported by the second end cover 13, and the intermediate portion of the rotor shaft 2 between the first end portion 21 and the second end portion 22 is supported by the main body 11. The middle portion is located at an edge of the first receiving space 40 adjacent to the second receiving space 50. Specifically, the support of the rotor shaft 2 is achieved by a first bearing 4, a second bearing 5, and a third bearing 6, respectively, which will be described in detail below.

In the present embodiment, the housing 1 is a housing shared by the motor 100 and the decelerator assembly 200.

In the present embodiment, the first bearing 4 supports the rotor shaft 2 at a first end 21, and the second bearing 5 supports the rotor shaft 2 at a second end 22. The third bearing 6 supports the rotor shaft 2 between the rotor 110 and the input gear 101. Specifically, the third bearing 6 supports the above-described intermediate portion of the rotor shaft 2.

Specifically, the first bearing 4 is mounted within the first end cap 12 and the second bearing 5 is mounted within the second end cap 13. First end cover 12 and second end cover 13 can form the bearing mounting hole that is used for the installation bearing integratively, compares and sets up the bearing frame of seting up the dead eye alone and again with this bearing frame be connected to the casing, the simplification of the structure of being more convenient for, and more do benefit to the machining precision who guarantees the dead eye.

In the present exemplary embodiment, the rotor shaft 2 forms a shoulder between the third bearing 6 and the rotor 110, against which the third bearing rests, the radial dimension of the rotor shaft 2 between the shoulder and the first end 21 being smaller than the inner ring diameter of the third bearing 6.

In this specification, the term "shoulder" refers to a portion of the stepped shaft where the cross-sectional dimension changes. The shoulder has a larger diameter and a smaller diameter, referred to as major and minor diameters, respectively, at the section change. In the present embodiment, the small diameter of the shoulder is close to the first accommodation space 40, and the large diameter of the shoulder is close to the second accommodation space 50.

In this embodiment, the rotor shaft 2 may also be provided with a snap ring 3, the snap ring 3 abutting against a side of the third bearing 6 opposite to the shoulder. Specifically, the third bearing 6 is mounted in a bearing mounting hole of the main body 11, and one side of the third bearing 6 abuts against a shoulder and the other side is abutted by the snap ring 3, thereby mounting the third bearing 6 in place.

Further, the rotor shaft 2 may be provided with a mounting groove to receive the snap ring 3 to fix the position of the snap ring 3.

Exemplarily, a circumferentially extending lip seal 9 is arranged between the rotor shaft 2 and the main body and adjacent to the third bearing 6, which lip seal 9 is a bidirectional seal. A lip seal 9 is provided on the side of the third bearing 6 opposite the snap ring 3.

Exemplarily, a shaft bore extending along the rotation axis a within the rotor shaft 2 is provided at the first end 21. Optionally, the shaft bore extends beyond the shoulder along the axis of rotation a. Through setting up the shaft hole, can alleviate the whole weight of rotor shaft 2 when guaranteeing bulk strength.

Illustratively, at least one of the first bearing 4, the second bearing 5, and the third bearing 6 is a deep groove ball bearing. In the present embodiment, the first bearing 4, the second bearing 5, and the third bearing 6 are all deep groove ball bearings.

Exemplarily, the speed reducer assembly 200 may be a two-stage helical gear parallel shaft speed reducer arrangement, the electric drive assembly system being provided with a differential 20, the differential 20 being disposed within the first accommodation space 40 and being coupled to the speed reducer arrangement. FIG. 2 illustrates, by way of example and not limitation, a two-stage helical gear parallel shaft reducer arrangement.

The reducer assembly 200 may include an input gear 101, an intermediate first gear 102, and an intermediate second gear 103. As described above, the input gear 101 is formed integrally with the rotor shaft 2. An intermediate first gear 102 and an intermediate second gear 103 are arranged in turn on an intermediate shaft 104. The intermediate shaft 104 is arranged parallel to the rotor shaft 2, the intermediate shaft 104 may be a hollow shaft. The dimensions of the input gear 101, the intermediate first gear 102 and the intermediate second gear 103 may be chosen according to the actual requirements. An intermediate first gear 102 is in driving engagement with the input gear 101 and an intermediate second gear 103 may be bolted to the differential 20. A two-stage helical gear parallel shaft reduction arrangement from the rotor shaft 2 to the differential 20 is thus realized by way of example.

Optionally, the reducer arrangement and differential 20 are provided with deep groove ball bearings. For example, both ends of the intermediate shaft 104 and both ends of the differential 20 may be supported by deep groove ball bearings, respectively. Half of the deep groove ball bearings are mounted in the first end cap 12 and the other half of the deep groove ball bearings are mounted in the main body 11.

Optionally, the electric drive assembly system may further comprise a cooling heat exchange system. The cooling and heat exchanging system is, for example, a circulating water cooling system, which is disposed in the second accommodating space 50 and cools the stator of the motor 100 by water cooling. The cooling heat exchange system may further comprise heat sinks for enhanced heat dissipation, which may be formed integrally with the second end cap 13 or fixedly connected to the second end cap 13.

Furthermore, the electric drive assembly system may further include an inverter housing 301, the inverter housing 301 being fixed to the housing 1. To sum up, the connection and arrangement between the motor 100, the reducer assembly 200, and the inverter 300 are thus formed.

According to another aspect of the present invention, a vehicle is provided comprising an electric drive assembly system as described above. In particular, the vehicle may be an electric car.

The above description is only for the specific embodiments of the present disclosure, but the scope of the embodiments of the present disclosure is not limited thereto, and any person skilled in the art can easily conceive of the changes, substitutions or combinations within the technical scope of the embodiments of the present disclosure or under the concept of the embodiments of the present disclosure, and all of them should be covered by the scope of the embodiments of the present disclosure.

Claims

1. An electric drive assembly system comprising:

the shell comprises a main body, a first end cover and a second end cover, wherein the first end cover and the second end cover are arranged at two opposite ends of the main body;

the speed reducer assembly is positioned in a first accommodating space formed by the main body and the first end cover in a surrounding mode; and

a rotor shaft having a rotation axis and having a first end portion adjacent to the first end cover along the rotation axis and a second end portion opposite to the first end portion, the rotor shaft being rotationally fixed to a rotor of the motor, the rotor being accommodated in a second accommodation space surrounded by the main body and the second end cover;

wherein an input gear of the speed reducer assembly is integrally formed on the rotor shaft, the input gear being disposed coaxially with the rotor shaft,

wherein the shell is a shell shared by the motor and the speed reducer component,

wherein the electric drive assembly system further comprises:

a first bearing supporting the rotor shaft at a first end;

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

a third bearing supporting the rotor shaft between the rotor and the input gear and mounted within the body,

wherein the rotor shaft forms a shoulder between the third bearing and the rotor against which the third bearing abuts, the rotor shaft having a radial dimension between the shoulder to the first end that is less than an inner race diameter of the third bearing.

2. The electric drive assembly system of claim 1, wherein the first bearing is mounted within a first end cap and the second bearing is mounted within a second end cap.

3. The electric drive assembly system of claim 1, wherein the rotor shaft is further provided with a snap ring that abuts a side of the third bearing opposite the shoulder.

4. The electric drive assembly system of claim 3, wherein a circumferentially extending lip seal is disposed between the rotor shaft and the main body and adjacent the third bearing, the lip seal being disposed on a side of the third bearing opposite the snap ring.

5. The electric drive assembly system of claim 1, wherein a shaft bore extending along an axis of rotation within the rotor shaft is provided at the first end.

6. The electric drive assembly system of claim 5, wherein the shaft bore extends beyond the shoulder along the axis of rotation.

7. The electric drive assembly system of claim 1, wherein at least one of the first, second, and third bearings is a deep groove ball bearing.

8. The electric drive assembly system of claim 1, wherein the speed reducer assembly is a two-stage helical gear parallel shaft speed reducer arrangement.

9. The electric drive assembly system of claim 8, wherein the electric drive assembly system is provided with a differential disposed within the first housing space and coupled to the speed reducer arrangement.

10. The electric drive assembly system of claim 9, wherein the speed reducer arrangement and differential are provided with deep groove ball bearings.

11. The electric drive assembly system of claim 1, further comprising: an inverter housing fixed to the motor housing.

12. A vehicle comprising an electric drive assembly system according to any one of claims 1-11.