Coaxial electric drive assembly structure and vehicle

Abstract

The invention discloses a coaxial type electric drive assembly structure and a vehicle, the coaxial type electric drive assembly structure comprises a shell, a rotating shaft arranged in the shell, and a stator and rotor mechanism, a speed reducing mechanism and a differential mechanism which are coaxially connected to the rotating shaft, the rotating shaft comprises a motor shaft with an axial through hole and an output half shaft coaxially arranged in the axial through hole of the motor shaft, and a motor bearing which is used for supporting the output half shaft and enabling the output half shaft to rotate relative to the motor shaft is arranged in the motor shaft. A coaxial design is adopted, and a stator and rotor mechanism, a speed reducing mechanism and a rotating shaft are ingeniously combined, so that the whole electric drive assembly is more compact in structure, can use a bearing with a smaller size, can use a water-cooled motor, and is lower in cost and smaller in outer envelope size; the electric corrosion resistance of the bearing is higher, and meanwhile the peak rotating speed of the motor is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of parts for new energy vehicles, and in particular to a coaxial electric drive assembly structure and a vehicle. Background Art

[0002] At present, the coaxial electric drive assembly uses a planetary reducer to replace the traditional reducer, which can effectively reduce the outer envelope size of the assembly and reduce the weight of the assembly. At the same time, the half-shaft interface of the coaxial electric drive assembly is located at both ends of the assembly, which is more friendly to the connection of the entire vehicle.

[0003] The existing coaxial electric drive assembly uses a drive motor and a planetary gear reducer to provide power for the entire vehicle. The motor shaft is a hollow shaft, and the output half shaft passes through the motor to connect the planetary gear and the entire vehicle.

[0004] The existing coaxial electric drive assembly is limited by the size of the rotating shaft, forcing it to use oil-cooled bearings, which means that the motor also needs to be oil-cooled. The oil-cooled motor needs to be used with oil pumps, oil coolers and other parts, which will increase the cost and increase the outer envelope. At the same time, oil-cooled bearings will also cause electrical corrosion problems. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings of the above-mentioned background technology and provide a coaxial electric drive assembly structure and vehicle that does not require oil-cooled bearings and can use water cooling to cool the motor, has a small outer envelope size, and has strong electrical corrosion resistance.

[0006] To achieve this purpose, the coaxial electric drive assembly structure designed in the present invention includes a housing, a rotating shaft arranged inside the housing, and a stator-rotor mechanism, a reduction mechanism and a differential coaxially connected to the rotating shaft. The rotating shaft includes a motor shaft having an axial through hole and an output half shaft coaxially arranged in the axial through hole of the motor shaft. A motor bearing is arranged in the motor shaft for supporting the output half shaft and enabling the output half shaft to rotate relative to the motor shaft.

[0007] Furthermore, the motor bearing includes a front motor bearing and a rear motor bearing coaxially matched with the front and rear sides of the middle part of the output half shaft, and the front motor bearing and the rear motor bearing are arranged between the motor shaft and the output half shaft through an axial positioning structure.

[0008] Furthermore, the axial positioning structure includes a shaft shoulder arranged on the hole wall of the axial through hole of the motor shaft and a retaining spring or a pressure ring coaxially arranged on the output half shaft.

[0009] Furthermore, the stator-rotor mechanism is coaxially connected to the shaft section of the motor shaft between the motor front bearing and the motor rear bearing.

[0010] Furthermore, a shaft oil seal coaxially connected to the output half-shaft is provided between the front end of the motor shaft and the output half-shaft to prevent the oil inside the motor shaft from leaking out.

[0011] Furthermore, the front end of the output half shaft passes through the motor shaft and is coaxially connected to the differential.

[0012] Furthermore, the reduction mechanism includes a planetary gear, and a planetary gear input gear for driving the planetary gear is coaxially fixed to the front end of the motor shaft.

[0013] Furthermore, a front output oil seal and a rear output oil seal are respectively arranged inside the front and rear sides of the shell to prevent the oil inside the shell from leaking out.

[0014] Furthermore, the shell includes an electric drive compartment for arranging the stator-rotor mechanism and an output compartment for arranging the reduction mechanism and the differential, and a motor oil seal for separating the oil in the electric drive compartment and the oil in the output compartment is coaxially connected to the rotating shaft.

[0015] Still further, a vehicle includes the coaxial electric drive assembly structure described above.

[0016] The beneficial effects of the present invention are as follows: the coaxial design is adopted to skillfully combine the stator-rotor mechanism, the speed reduction mechanism and the rotating shaft, so that the entire electric drive assembly structure is more compact, smaller bearings can be used, and water-cooled motors can be used, which has lower cost and smaller outer envelope size; the water-cooled motor can use grease-lubricated bearings, and the grease in the bearings can form a more stable oil film, so that the bearings have stronger electrical corrosion resistance; at the same time, during the driving of the vehicle, the motor shaft and the output half-shaft rotate in the same direction, that is, the inner and outer rings of the bearings of the front bearing of the motor and the rear bearing of the motor rotate in the same direction, the relative speed of the inner and outer rings is lower than the speed of the motor shaft, and the working speed of the front bearing of the motor and the rear bearing of the motor is always lower than the running speed of the motor, so the peak speed of the motor can be increased. The output half-shaft is nested in the motor shaft, which reduces the lateral space occupation, and leaves more layout space for other components in the limited vehicle installation space, which helps to realize the lightweight design of the vehicle and improve energy utilization efficiency. The coaxial connection ensures the direct transmission of power from the stator-rotor mechanism to the speed reduction mechanism, reduces the energy loss caused by the bending or dislocation of the transmission path, improves the power transmission efficiency, and makes the vehicle more responsive and has better acceleration performance during driving. The motor bearing is set inside the motor shaft to support the output half shaft. The front and rear motor bearings are closely matched with the output half shaft through the axial positioning structure, which not only ensures the stable axial position of the output half shaft in the motor shaft, but also allows it to rotate flexibly relative to the motor shaft, ensuring stable power output, reducing half shaft shaking and wear, and extending service life. Under complex driving conditions such as frequent vehicle start-stop, sudden acceleration, and sharp turns, this reliable half shaft support system can effectively withstand forces from all directions, maintain the normal operation of the output half shaft, and ensure the stability and safety of vehicle driving. Multiple oil seal designs, such as the shaft oil seal between the front end of the motor shaft and the output half shaft, the front output oil seal and the rear output oil seal on the front and rear sides of the housing, and the motor oil seal that separates the oil in the electric drive compartment and the reduction compartment, prevent oil leakage in all directions. This not only avoids oil waste and maintains the lubrication effect in the system, but also prevents oil from leaking to surrounding components to cause pollution, corrosion or short circuit, thereby improving the reliability and durability of the entire electric drive assembly. The output compartment integrates the differential and planetary gear, and the front end of the motor shaft coaxially fixes the planetary gear input gear, realizing the organic combination of deceleration, differential and motor drive functions. The various functional modules work closely together on the coaxial structure, reducing the intermediate connectors, having a higher degree of integration, simplifying the assembly process, reducing production costs, and improving the overall performance of the system, so that the vehicle can better adapt to different road conditions and driving requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a front view of the coaxial electric drive assembly structure of the present invention;

[0018] Figure 2 for Figure 1 Middle AA section view;

[0019] Among them, 1—housing (1.1—main housing, 1.2—end cover, 1.3—left housing), 2—rotating shaft (2.1—motor shaft, 2.2—output half shaft), 3—stator and rotor mechanism, 4—reduction mechanism (4.1—planetary gear), 5—differential, 6—motor front bearing, 7—motor rear bearing, 8—shaft shoulder, 9—circlip, 10—pressure ring, 11—rotating shaft oil seal, 12—planetary gear input gear, 13—front output oil seal, 14—rear output oil seal, 15—electric drive compartment, 16—output compartment, 17—motor oil seal, 18—differential bearing, 19—planetary gear bearing, 20—rear output bearing, 21—cooling water channel. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. In the description of the present invention, it should be understood that the orientations or positional relationships indicated by the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0021] like Figure 1 —2, in certain embodiments, the coaxial electric drive assembly structure designed by the present invention includes a housing 1, a rotating shaft 2 arranged inside the housing 1, and a stator-rotor mechanism 3, a reduction mechanism 4 and a differential 5 coaxially connected to the rotating shaft 2, the rotating shaft 2 includes a motor shaft 2.1 with an axial through hole and an output half shaft 2.2 coaxially arranged in the axial through hole of the motor shaft 2.1, and a motor bearing is arranged in the motor shaft 2.1 for supporting the output half shaft 2.2 and allowing the output half shaft 2.2 to rotate relative to the motor shaft 2.1.

[0022] Embodiment 1

[0023] On the basis of some of the above embodiments, the motor bearing includes a motor front bearing 6 and a motor rear bearing 7 coaxially matched with the front and rear sides of the middle of the output half shaft 2.2, and the motor front bearing 6 and the motor rear bearing 7 are arranged between the motor shaft 2.1 and the output half shaft 2.2 through an axial positioning structure. The axial positioning structure includes a shoulder 8 arranged on the hole wall of the axial through hole of the motor shaft 2.1 and a retaining spring 9 or a pressure ring 10 coaxially arranged on the output half shaft 2.2. The stator and rotor mechanism 3 is coaxially connected to the shaft section of the motor shaft 2.1 located between the motor front bearing 6 and the motor rear bearing 7. The front end of the output half shaft 2.2 passes through the motor shaft 2.1 and is coaxially connected to the differential 5. The reduction mechanism 4 includes a planetary gear 4.1, and the front end of the motor shaft 2.1 is coaxially fixed with a planetary gear input gear 12 for driving the planetary gear 4.1.

[0024] Embodiment 2

[0025] On the basis of some of the above embodiments or embodiment 1, a shaft oil seal 11 coaxially connected to the output half shaft 2.2 is provided between the front end of the motor shaft 2.1 and the output half shaft 2.2, for preventing the oil inside the motor shaft 2.1 from leaking out. A front output oil seal 13 and a rear output oil seal 14 are provided inside the front and rear sides of the housing 1, respectively, for preventing the oil inside the housing 1 from leaking out. The housing 1 includes an electric drive compartment 15 for arranging the stator-rotor mechanism 3 and an output compartment 16 for arranging the reduction mechanism 4 and the differential 5. A motor oil seal 17 is coaxially connected to the shaft 2 for separating the oil in the electric drive compartment 15 and the oil in the output compartment 16.

[0026] Embodiment 3

[0027] Based on some of the above embodiments or embodiment one or embodiment two, a vehicle is provided, comprising the above coaxial electric drive assembly structure.

[0028] In the present invention, a coaxial design is adopted to skillfully combine the stator-rotor mechanism 3, the speed reduction mechanism 4 and the rotating shaft 2, so that the entire electric drive assembly structure is more compact, smaller bearings can be used, and water-cooled motors can be used, which has lower cost and smaller outer envelope size; water-cooled motors can use grease-lubricated bearings, and the grease in the bearings can form a more stable oil film, so that the electrical corrosion resistance of the bearings is stronger; at the same time, during the driving of the vehicle, the motor shaft 2.1 and the output half shaft 2.2 rotate in the same direction, that is, the inner and outer rings of the bearings of the motor front bearing 6 and the motor rear bearing 7 rotate in the same direction, and the relative speed of the inner and outer rings is lower than the speed of the motor shaft 2.1, and the working speed of the motor front bearing 6 and the motor rear bearing 7 is always lower than the motor running speed, so the peak speed of the motor can be increased. The output half shaft 2.2 is nested in the motor shaft 2.1, which reduces the lateral space occupation, and leaves more layout space for other components in the limited vehicle installation space, which helps to achieve the lightweight design of the vehicle and improve energy utilization efficiency. The coaxial connection ensures the direct transmission of power from the stator-rotor mechanism 3 to the reduction mechanism 4, reduces the energy loss caused by the bending or misalignment of the transmission path, improves the power transmission efficiency, and makes the vehicle more responsive and has better acceleration performance during driving. A motor bearing is arranged in the motor shaft 2.1 to support the output half shaft 2.2. The motor front bearing 6 and the motor rear bearing 7 are closely matched with the output half shaft 2.2 through the axial positioning structure, which not only ensures the stable axial position of the output half shaft 2.2 in the motor shaft 2.1, but also allows it to rotate flexibly relative to the motor shaft, ensuring stable power output, reducing half shaft shaking and wear, and extending service life. Under complex driving conditions such as frequent vehicle start-stop, rapid acceleration, and sharp turns, this reliable half shaft support system can effectively withstand forces from all directions, maintain the normal operation of the output half shaft 2.2, and ensure the stability and safety of vehicle driving. Multiple oil seal designs, such as the shaft oil seal 11 between the front end of the motor shaft 2.1 and the output half shaft 2.2, the front output oil seal 13 and the rear output oil seal 14 on the front and rear sides of the housing 1, and the motor oil seal 17 that separates the oil in the electric drive compartment 15 and the reduction compartment 16, prevent oil leakage in all directions. This not only avoids oil waste and maintains the lubrication effect in the system, but also prevents oil from leaking to surrounding components to cause pollution, corrosion or short circuit, thereby improving the reliability and durability of the entire electric drive assembly. The differential 5 and the planetary gear 4.1 are integrated in the output compartment 16, and the front end of the motor shaft 2.1 is coaxially fixed with the planetary gear input gear 12, realizing the organic combination of reduction, differential and motor drive functions. The functional modules work closely together on the coaxial structure, reducing the intermediate connectors, having a higher degree of integration, simplifying the assembly process, reducing production costs, and improving the overall performance of the system, so that the vehicle can better adapt to different road conditions and driving requirements.

[0029] It should be noted that the description of the above technical solutions is exemplary, and this specification can be embodied in different forms and should not be construed as being limited to the technical solutions set forth herein. On the contrary, providing these descriptions will make the disclosure of the present invention thorough and complete, and will fully convey the scope disclosed in this specification to those skilled in the art. In addition, the technical solution of the present invention is limited only by the scope of the claims. In the case of using "including", "having" and "comprising" described in this specification, there may also be another part or other parts, and the terms used may generally be singular but may also represent plural forms. Finally, it should be pointed out that the above embodiments are only more representative examples of the present invention. Obviously, the present invention is not limited to the above embodiments, and there may be many variations. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention shall be deemed to belong to the protection scope of the present invention.

Claims

1. A coaxial electric drive assembly structure, comprising a housing (1), a rotating shaft (2) disposed inside the housing (1), and a stator-rotor mechanism (3), a speed reduction mechanism (4) and a differential (5) coaxially connected to the rotating shaft (2), characterized in that: The rotating shaft (2) comprises a motor shaft (2.1) having an axial through hole and an output half shaft (2.2) coaxially arranged in the axial through hole of the motor shaft (2.1); a motor bearing is arranged in the motor shaft (2.1) for supporting the output half shaft (2.2) and enabling the output half shaft (2.2) to rotate relative to the motor shaft (2.1).

2. The coaxial electric drive assembly structure according to claim 1, characterized in that: The motor bearing comprises a motor front bearing (6) and a motor rear bearing (7) which are coaxially matched with the front and rear sides of the middle part of the output half shaft (2.2); the motor front bearing (6) and the motor rear bearing (7) are arranged between the motor shaft (2.1) and the output half shaft (2.2) via an axial positioning structure.

3. The coaxial electric drive assembly structure according to claim 2, characterized in that: The axial positioning structure comprises a shaft shoulder (8) arranged on the hole wall of the axial through hole of the motor shaft (2.1) and a retaining spring (9) or a pressure ring (10) coaxially arranged on the output half shaft (2.2).

4. The coaxial electric drive assembly structure according to claim 2, characterized in that: The stator-rotor mechanism (3) is coaxially connected to the shaft section of the motor shaft (2.1) located between the motor front bearing (6) and the motor rear bearing (7).

5. The coaxial electric drive assembly structure according to claim 2, characterized in that: A rotating shaft oil seal (11) coaxially connected to the output half shaft (2.2) is provided between the front end of the motor shaft (2.1) and the output half shaft (2.2) to prevent oil inside the motor shaft (2.1) from leaking out.

6. The coaxial electric drive assembly structure according to claim 1, characterized in that: The front end of the output half shaft (2.2) passes through the motor shaft (2.1) and is coaxially connected to the differential (5).

7. The coaxial electric drive assembly structure according to claim 6, characterized in that: The speed reduction mechanism (4) comprises a planetary gear (4.1), and a planetary gear input gear (12) for driving the planetary gear (4.1) is coaxially fixed to the front end of the motor shaft (2.1).

8. The coaxial electric drive assembly structure according to claim 1, characterized in that: A front output oil seal (13) and a rear output oil seal (14) are respectively arranged inside the front and rear sides of the housing (1) to prevent the oil inside the housing (1) from leaking out.

9. The coaxial electric drive assembly structure according to claim 1, characterized in that: The housing (1) includes an electric drive compartment (15) for arranging the stator-rotor mechanism (3) and an output compartment (16) for arranging the reduction mechanism (4) and the differential (5), and a motor oil seal (17) for separating the oil in the electric drive compartment (15) and the oil in the output compartment (16) is coaxially connected to the rotating shaft (2).

10. A vehicle, characterized in that: It includes the coaxial electric drive assembly structure described in any one of claims 1 to 9.

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