Double-motor two-stage transmission electric drive axle

Abstract

The utility model discloses a double-motor two-stage transmission electric drive axle, and belongs to the technical field of new energy automobile electric drive. The drive axle solves the technical problems of insufficient power and transmission efficiency attenuation of a commercial vehicle under complex working conditions through the innovative combination of dual-motor cooperative driving and a two-stage transmission structure. The first driving motor and the second driving motor are axially arranged in parallel, output gears of the first driving motor and the second driving motor are meshed with an input gear of an intermediate shaft to form two-stage speed reduction transmission, and a differential receives power through an output gear of the intermediate shaft. The hollow shaft design enables the left half shaft to penetrate through the rotor shaft of the first driving motor, coaxial layout of the differential mechanism and the motor is achieved, the transmission stage number is reduced compared with a traditional three-stage speed reduction system, and mechanical efficiency is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of double motor electric drive axle, concretely relates to a double motor secondary transmission electric drive axle. BACKGROUND

[0002] Commercial vehicles, as means of production, have become the core concern of users in their full life cycle economy. With the progress of three-electric technology and the emergence of operating cost advantages, new energy commercial vehicles are accelerating the penetration from urban logistics scenarios to intercity and urban-rural logistics scenarios. It is worth noting that intercity and urban-rural logistics transportation generally faces more complex working conditions, especially full-load starting, mountain climbing and other scenarios, which put higher requirements on the continuous torque output of the drive system. The traditional single motor electric drive system has been difficult to meet the actual operation needs.

[0003] In view of the above technical pain points, the existing technology such as CN114771228A proposes a double motor three-stage transmission electric drive axle scheme, which improves the system power density by arranging double power sources in parallel. However, in-depth research shows that this scheme has significant technical bottlenecks: first, although the three-stage reduction structure can amplify torque, as the total reduction ratio increases, the mechanical transmission efficiency decreases nonlinearly, directly affecting the vehicle's range; second, the double motor double-sided arrangement mode leads to an increase in the size of the electric drive axle, which conflicts with the trend of compact design of commercial vehicle chassis. How to achieve an optimal balance between transmission efficiency and spatial layout while ensuring power performance has become a key technical problem that needs to be solved for new energy commercial vehicle electric drive systems. SUMMARY

[0004] The utility model aims at corresponding insufficient of prior art, provides a kind of double motor secondary transmission electric drive axle, this double motor secondary transmission electric drive axle is passed through being arranged first drive motor and second drive motor, first drive motor and second drive motor are shared with the intermediate shaft input gear on intermediate shaft and are transmitted power, the rotor shaft of first drive motor is hollow shaft, left half axle is connected with differential through rotor shaft, realizes efficient transmission and compact layout.

[0005] The utility model is realized by the following scheme:

[0006] A double motor secondary transmission electric drive axle, comprising an electric drive axle housing, a reducer gear set and a differential are supported in the electric drive axle housing, and a first drive motor and a second drive motor are also supported in the electric drive axle housing and arranged axially in parallel;

[0007] The reducer gear set is a two-stage transmission gear set, comprising an intermediate shaft, an intermediate shaft input gear on the intermediate shaft is shared with a first output gear of the first drive motor and a second output gear of the second drive motor, and an intermediate shaft output gear on the intermediate shaft is engaged with a differential input gear to transmit power;

[0008] The first driving motor and the differential are coaxially arranged, the motor shaft of the first driving motor is a hollow shaft, one end of the left half shaft is connected with the left half shaft bevel gear of the differential through the inner hole of the motor shaft of the first driving motor, and the other end of the left half shaft extends out of the electric drive axle housing and is connected with the left hub, one end of the right half shaft is connected with the right half shaft bevel gear of the differential, and the other end of the right half shaft extends out of the electric drive axle housing and is connected with the right hub.

[0009] Preferably, the first driving motor and the second driving motor each comprise a motor stator and a motor rotor, the motor rotor is located in the motor stator, the first output gear of the first driving motor is located on the rotor shaft of the first driving motor, and the second output gear of the second driving motor is located on the rotor shaft of the second driving motor.

[0010] Preferably, the electric drive axle housing is provided with a first driving motor mounting cavity and a second driving motor mounting cavity, and the first driving motor mounting cavity and the second driving motor mounting cavity are separated by a cavity wall.

[0011] Preferably, the electric drive axle housing is provided with a first driving motor mounting cavity and a second driving motor mounting cavity, and the first driving motor mounting cavity and the second driving motor mounting cavity are separated by a cavity wall.

[0012] Preferably, the rotor shaft of the first driving motor, the rotor shaft of the second driving motor, the intermediate shaft and the differential are respectively supported in the electric drive axle housing through bearings.

[0013] The beneficial effects of the utility model are as follows:

[0014] Good power performance and high transmission efficiency: through the design of double-motor collaborative driving and two-stage transmission structure, the meshing layout of the intermediate shaft input gear and the double-motor output gear realizes two-stage speed reduction, the double-motor collaborative driving effectively solves the problem of insufficient power of commercial vehicles under full-load climbing working conditions, and the two-stage speed reduction has higher mechanical transmission efficiency than three-stage speed reduction, so that the cruising range of the vehicle can be significantly prolonged; and, the single-motor driving mode or the double-motor driving mode can be flexibly switched according to the working conditions, for example, the single motor is operated during high-speed cruising, and the double motors are output during climbing, so that the electric energy can be efficiently utilized.

[0015] Spatial layout innovation: through the design of the hollow shaft of the first driving motor, the left half shaft and the motor rotor form a coaxial layout, this structure meets the compactness requirement of the commercial vehicle chassis, reduces the volume of the driving system, and provides more space for the battery pack and other systems. The electric drive axle housing adopts a split-cavity design, the double-motor mounting cavities are isolated, and the system NVH performance is effectively improved.

[0016] Reliability improvement: the double-motor design, when a single motor fails, the remaining motor can still maintain the basic driving ability of the vehicle through two-stage transmission, so as to guarantee the emergency driving ability of the vehicle and significantly improve the operation safety of the commercial vehicle.

[0017] In summary, this technology improves power performance and transmission efficiency through dual-motor collaborative drive and a two-stage transmission structure, solving the problem of insufficient power for commercial vehicles when climbing hills under full load. It also extends the driving range by intelligent switching between single and dual motors (such as high-speed single drive and hill-climbing dual drive). The innovative hollow shaft coaxial layout and split-cavity electric drive axle housing design achieve compact space optimization and improved NVH performance. The dual-motor redundancy system can maintain emergency driving capability in the event of a single motor failure, significantly improving the operational safety and reliability of commercial vehicles. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model. Detailed Implementation

[0019] like Figure 1 As shown, a dual-motor two-stage transmission electric drive axle includes an integrally formed electric drive axle housing 1. The electric drive axle housing 1 includes a first drive motor mounting cavity 20, a second drive motor mounting cavity 21, a differential and reducer gear set mounting cavity, and half-shaft mounting cavities 16 extending outward on both sides. The first drive motor mounting cavity 20, the second drive motor mounting cavity 21, and the differential and reducer gear set mounting cavity are all separated by cavity walls 22. The first drive motor mounting cavity 20 supports a first drive motor 3, and the second drive motor mounting cavity 21 supports a second drive motor 4. The first drive motor 3 and the second drive motor 4 are arranged axially parallel to each other. The differential and reducer gear set mounting cavity supports a reducer gear set and a differential 2.

[0020] The reducer gear set is a two-stage transmission gear set, including an intermediate shaft 5. An intermediate shaft input gear 6 fixedly mounted on the intermediate shaft 5 meshes with the first output gear 7 of the first drive motor 3 and the second output gear 8 of the second drive motor 4. The meshing means that the intermediate shaft input gear 6 simultaneously meshes with the first output gear 7 and the second output gear 8. An intermediate shaft output gear 9 fixedly mounted on the intermediate shaft 5 meshes with the differential input gear 10 to transmit power. The power is generated by the first drive motor 3 and / or the second drive motor 4 individually or jointly, and transmitted to the differential 2 through the reducer gear set and then to the half shaft.

[0021] Both the first drive motor 3 and the second drive motor 4 include a motor stator 18 and a motor rotor 19. The motor rotor 19 is located inside the motor stator 18. The first output gear 7 of the first drive motor 3 is located on the rotor shaft of the first drive motor 3, and the second output gear 8 of the second drive motor 4 is located on the rotor shaft of the second drive motor 4. The rotor shafts of the first drive motor 3, the second drive motor 4, the intermediate shaft 5, and the differential 2 are respectively supported in the electric drive bridge housing 1 by bearings.

[0022] The first driving motor 3, the differential 2 and the half shaft mounting cavity 16 are coaxially arranged, the motor shaft of the first driving motor 3 is a hollow shaft 11, one end of the left half shaft 12 is connected with the left half shaft bevel gear of the differential 2 through the inner hole of the motor shaft of the first driving motor 3, and the other end of the left half shaft 12 extends out of the electric drive axle housing 1 and is connected with the left wheel hub 14; one end of the right half shaft 15 is connected with the right half shaft bevel gear of the differential 2, and the other end of the right half shaft 15 extends out of the electric drive axle housing 1 and is connected with the right wheel hub 17; the left half shaft 12 extending out of the left half shaft mounting cavity 16 is connected with the left wheel hub 14, and the right half shaft 15 extending out of the right half shaft mounting cavity 16 is connected with the right wheel hub 17.

[0023] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification made by those skilled in the art without departing from the spirit of the present application shall fall within the scope of the present application.

Claims

1. A dual-motor two-stage transmission electric drive axle comprising an electric drive axle housing (1), a reduction gear set and a differential (2) supported in the electric drive axle housing (1), characterized in that: The electric drive axle housing (1) further supports a first drive motor (3) and a second drive motor (4) arranged axially in parallel; The reducer gear set is a two-stage transmission gear set, comprising an intermediate shaft (5), an intermediate shaft input gear (6) on the intermediate shaft (5) is in mesh with a first output gear (7) of the first drive motor (3) and a second output gear (8) of the second drive motor (4), and an intermediate shaft output gear (9) on the intermediate shaft (5) is in mesh with a differential input gear (10) to transmit power. The first drive motor (3) and the differential (2) are coaxially arranged, the motor shaft of the first drive motor (3) is a hollow shaft (11), one end of a left half shaft (12) is connected with a left half shaft bevel gear of the differential (2) through the inner hole of the motor shaft of the first drive motor (3), and the other end of the left half shaft (12) extends out of the electric drive axle housing (1) and is connected with a left wheel hub (14), one end of a right half shaft (15) is connected with a right half shaft bevel gear of the differential (2), and the other end of the right half shaft (15) extends out of the electric drive axle housing (1) and is connected with a right wheel hub (17).

2. The dual-motor, two-speed transaxle electric drive axle of claim 1, wherein: The first drive motor (3) and the second drive motor (4) each comprise a motor stator (18) and a motor rotor (19), the motor rotor (19) is located in the motor stator (18), the first output gear (7) of the first drive motor (3) is located on a rotor shaft of the first drive motor (3), and the second output gear (8) of the second drive motor (4) is located on a rotor shaft of the second drive motor (4).

3. The dual-motor, two-speed transaxle electric drive axle of claim 1, wherein: The electric drive axle housing (1) is provided with a first drive motor mounting cavity (20) and a second drive motor mounting cavity (21), and the first drive motor mounting cavity (20) and the second drive motor mounting cavity (21) are separated by a cavity wall (22).

4. The dual-motor, two-speed transaxle electric drive axle of claim 1, wherein: The electric drive axle housing (1) is provided with a half shaft mounting cavity (16) extending outward on each side, the left half shaft (12) extends out of the half shaft mounting cavity (16) on the left side and is connected with the left wheel hub (14), and the right half shaft (15) extends out of the half shaft mounting cavity (16) on the right side and is connected with the right wheel hub (17).

5. The dual-motor, two-speed transaxle electric drive axle of claim 1, wherein: The rotor shaft of the first drive motor (3), the rotor shaft of the second drive motor (4), the intermediate shaft (5), and the differential (2) are respectively supported in the electric drive axle housing (1) by bearings.

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