Coaxial electric drive, driving system and automobile

Abstract

The utility model provides a coaxial electric drive, a driving system and an automobile, the coaxial electric drive comprises a driving motor, a differential mechanism and a plurality of intermediate shafts, and a first driving gear is arranged on a motor rotating shaft of the driving motor; the differential mechanism and the driving motor are coaxially arranged, a second driven gear is arranged on the differential mechanism and is parallel to the first driving gear, and the circle center of the second driven gear and the circle center of the first driving gear are located on the straight line where the motor rotating shaft is located; the multiple intermediate shafts are distributed in the circumferential direction of the first driving gear and the second driving gear and are parallel to the motor rotating shaft, the multiple intermediate shafts are kept fixed relative to the position of a stator of the driving motor, and each intermediate shaft is fixedly provided with a first driven gear and a second driving gear; the first driven gear and the second driving gear are distributed in the axial direction of the intermediate shaft, the first driven gear is meshed with the first driving gear, and the second driving gear is meshed with the second driven gear. The coaxial electric driver provided by the utility model has higher volume power density.

Description

Technical Field

[0001] This application relates to the field of automotive technology, and particularly to a coaxial electric drive, a drive system, and an automobile. Background Art

[0002] The electric drive system of a passenger car is usually arranged on the rear axle, and its overall vehicle layout space is greatly limited, which restricts the power and structure of the electric drive system. At the same time, with the continuous development of the overall vehicle technology, it is also necessary to improve the volume power density of the electric drive system. In addition, to be applicable to different vehicle platforms, the electric drive system is required to be highly integrated to improve cross-platform applicability. Therefore, an electric drive system with a relatively high volume power density is needed to meet the above requirements. Summary of the Utility Model

[0003] To at least partially solve the above problems, according to the first aspect of this application, an embodiment of this application provides a coaxial electric drive. The coaxial electric drive includes a drive motor, a differential, and a plurality of intermediate shafts. A first driving gear is arranged on the motor rotating shaft of the drive motor. The differential is coaxially arranged with the drive motor, and a second driven gear is arranged on the differential. The second driven gear is arranged parallel to the first driving gear, and the centers of the second driven gear and the first driving gear are located on the straight line where the motor rotating shaft is located. The plurality of intermediate shafts are circumferentially distributed along the first driving gear and the second driven gear and are parallel to the motor rotating shaft. The positions of the plurality of intermediate shafts relative to the stator of the drive motor are kept fixed. Wherein, a first driven gear and a second driving gear are fixedly arranged on each intermediate shaft. The first driven gear and the second driving gear are axially distributed along the intermediate shaft. The first driven gear meshes with the first driving gear, and the second driving gear meshes with the second driven gear.

[0004] In some embodiments, the plurality of intermediate shafts are evenly circumferentially distributed along the first driving gear and the second driven gear.

[0005] In some embodiments, the number of intermediate shafts is 3.

[0006] In some embodiments, the coaxial electric drive further includes a motor controller, and the motor controller is connected to the drive motor.

[0007] In some embodiments, the motor controller is annular, and the annular motor controller is coaxially arranged with the drive motor.

[0008] In some embodiments, a DC high-voltage interface and a three-phase wiring port are arranged on the motor controller. The DC high-voltage interface is used to connect to an external DC high-voltage power supply, and the three-phase wiring port is connected to the drive motor.

[0009] In some embodiments, a channel penetrating the motor shaft is axially formed in the motor shaft; a first half shaft and a second half shaft are respectively drivingly connected to two sides of the differential. The first half shaft is disposed in the channel and used to transmit power to the wheels on one side of the coaxial electric drive, and the second half shaft is used to transmit power to the wheels on the other side of the coaxial electric drive.

[0010] In some embodiments, the diameter of the first driven gear is larger than that of the second driving gear.

[0011] According to a second aspect of the present application, embodiments of the present application provide a drive system, and the drive system includes the coaxial electric drive provided in any embodiment of the present application.

[0012] According to a third aspect of the present application, embodiments of the present application provide a vehicle, and the vehicle includes the coaxial electric drive provided in any embodiment of the present application.

[0013] The coaxial electric drive, drive system and vehicle provided by the embodiments of the present application realize power transmission between the drive motor and the differential by arranging a plurality of intermediate shafts that remain fixed relative to the position of the drive motor stator. Compared with the method of transmitting power through a single intermediate shaft, it can compress the tooth widths and gear module numbers of the first driven gear and the second driving gear on each intermediate shaft to be smaller while ensuring the normal operation of the coaxial electric drive, thereby compressing the axial and radial dimensions of the coaxial electric drive and making the external shape of the coaxial electric drive more regular, and further improving the volume power density of the coaxial electric drive; compared with the method of realizing power transmission between the drive motor and the differential through a planetary gear set, it can avoid arranging an internal gear ring and a planet carrier, reduce the axial and radial dimensions of the coaxial electric drive, improve the volume power density of the coaxial electric drive, and at the same time avoid the machining and assembly of the internal gear ring, reducing the process complexity and material cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for description in the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0015] Figure 1 is a schematic structural diagram of the coaxial electric drive provided by the embodiments of the present application;

[0016] Figure 2 is a schematic structural diagram of the coaxial electric drive provided by another embodiment of the present application.

[0017] The reference numerals are as follows:

[0018] 1. First half shaft; 2. Half shaft bearing; 3. First motor shaft bearing; 4. Motor shaft; 5. Second motor shaft bearing; 6. First intermediate shaft bearing; 7. First differential bearing; 8. Intermediate shaft; 9. Second intermediate shaft bearing; 10. Differential; 11. Second differential bearing; 12. Drive motor; 13. Motor controller; 14. Three-phase wiring port; 15. DC high-voltage interface.

[0019] It should be understood that the dimensions of the various parts shown in the drawings are not drawn according to the actual proportional relationship. In addition, the same or similar reference numerals represent the same or similar components. Detailed implementation manners

[0020] The technical solutions of the preferred embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope protected by the present application.

[0021] The "first", "second" and similar terms used in the present application do not indicate any order, quantity or importance, but are only used to distinguish different parts. The terms such as "comprising" or "including" mean that the elements before this term cover the elements listed after this term, and do not exclude the possibility of also covering other elements. The terms such as "upper", "lower", "left" and "right" are only used to represent the relative positional relationship, and when the absolute position of the object to be described changes, the relative positional relationship may also change accordingly.

[0022] As Figure 1 shown, according to the first aspect of the present application, an embodiment of the present application provides a coaxial electric drive, which includes a drive motor 12, a differential 10 and a plurality of intermediate shafts 8.

[0023] The drive motor 12 may include a stator, a rotor and a motor shaft 4. The stator is the part that remains stationary when the drive motor 12 operates, and generally includes a stator core, a stator winding and a frame; the rotor is the part that rotates when the drive motor 12 operates, and generally includes a core wound with coils, slip rings, fan blades, etc.; the motor shaft 4 is fixedly connected to the rotation center of the rotor and serves as the rotation axis of the rotor. A first driving gear is provided on the motor shaft 4 of the drive motor 12, and the power generated by the drive motor 12 is output outward through the first driving gear.

[0024] The differential 10 is coaxially arranged with the drive motor 12. A second driven gear is arranged on the differential 10, and external power can be input to the differential 10 through the second driven gear. The second driven gear is arranged in parallel with the first driving gear, and the centers of the second driven gear and the first driving gear are located on the straight line where the motor rotating shaft 4 is located. That is to say, the second driven gear, the first driving gear and the motor rotating shaft 4 are coaxially arranged. The differential 10 and the first driving gear can be located on the same side of the drive motor 12.

[0025] A plurality of intermediate shafts 8 are circumferentially distributed along the first driving gear and the second driven gear and are parallel to the motor rotating shaft 4. The plurality of intermediate shafts 8 can have the same shape and size. The intermediate shafts 8 can realize the power transmission between the first driving gear and the second driven gear. Preferably, the plurality of intermediate shafts 8 are circumferentially and evenly distributed along the first driving gear and the second driven gear, so that the power transmission can be more stable. Exemplarily, the number of the intermediate shafts 8 can be 2, 3, 4, 5 or more. Preferably, the number of the intermediate shafts 8 is 3 to realize the stable power transmission with a smaller number of intermediate shafts 8. The positions of the plurality of intermediate shafts 8 relative to the stator of the drive motor 12 are kept fixed. That is to say, when the drive motor 12 operates, the axis positions of the intermediate shafts 8 remain stationary. Wherein, a first driven gear and a second driving gear are fixedly arranged on each intermediate shaft 8. The first driven gear and the second driving gear are axially distributed along the intermediate shaft 8. The first driven gear meshes with the first driving gear, and the second driving gear meshes with the second driven gear. In this application, due to the arrangement of the plurality of intermediate shafts 8, the power is transmitted through the gear meshing on the plurality of intermediate shafts 8, which is beneficial to reducing the axial dimension of the gears. The intermediate shaft 8 transmits the power between the first driving gear and the second driven gear through the first driven gear and the second driving gear. The first driven gear and the second driving gear can be integrally formed with the intermediate shaft 8 or can be fixedly connected to the intermediate shaft 8 by means of, for example, key pins.

[0026] The coaxial electric drive provided by the embodiment of this application realizes the power transmission between the drive motor 12 and the differential 10 by arranging a plurality of intermediate shafts 8 whose positions relative to the stator of the drive motor 12 are kept fixed. Compared with the method of transmitting power through a single intermediate shaft 8, it can compress the tooth width and gear module of the first driven gear and the second driving gear on each intermediate shaft 8 smaller while ensuring the normal operation of the coaxial electric drive, thereby compressing the axial and radial dimensions of the coaxial electric drive and making the external shape of the coaxial electric drive more regular, and further improving the volume power density of the coaxial electric drive; compared with the method of realizing the power transmission between the drive motor 12 and the differential 10 through a planetary gear set, it can avoid arranging an internal gear ring and a planet carrier, reduce the axial and radial dimensions of the coaxial electric drive, improve the volume power density of the coaxial electric drive, and at the same time avoid the processing and assembly of the internal gear ring, reducing the process complexity and material cost.

[0027] In some embodiments, the coaxial electric drive further includes a motor controller 13, and the motor controller 13 is connected to the drive motor 12. In this embodiment, the motor controller 13 is further integrated into the coaxial electric drive, avoiding the need to arrange the motor controller 13 in an additional space outside the electric drive. A DC high-voltage interface 15 and a three-phase wiring port 14 (UVW interface) may be provided on the motor controller 13. The DC high-voltage interface 15 is used to connect to an external DC high-voltage power supply; the three-phase wiring port 14 is connected to the drive motor 12.

[0028] As Figure 2 shown, in some embodiments, the motor controller 13 is annular, and the annular motor controller 13 is coaxially arranged with the drive motor 12. In this embodiment, by setting the motor controller 13 to be annular, the radial dimension of the coaxial electric drive can be further reduced, the volume power density of the coaxial electric drive can be increased, and it can be adapted to models with a smaller assembly space. The annular motor controller 13 can be arranged at one end of the stator of the drive motor 12 and coaxially arranged with the stator of the drive motor 12. Of course, in other embodiments, the motor controller 13 can also be square, and the square motor controller 13 has a simple structure and low cost.

[0029] Combined with Figure 1 and Figure 2 , in some embodiments, a channel penetrating the motor shaft 4 is axially formed in the motor shaft 4; the two sides of the differential 10 are respectively drivingly connected with a first half shaft 1 and a second half shaft. The first half shaft 1 is disposed through the channel and is used to transmit power to the wheels on one side of the coaxial electric drive, and the second half shaft is used to transmit power to the wheels on the other side of the coaxial electric drive. In this embodiment, through the above setting method, the differential 10 is coaxially arranged with the drive motor 12, and at the same time, left and right differential outputs are realized. Specifically, the first half shaft is rotatably arranged on the half shaft bearing 2, the two ends of the motor shaft 4 are respectively rotatably arranged on the first motor shaft bearing 3 and the second motor shaft bearing 5, the two ends of each intermediate shaft 8 are respectively rotatably arranged on the first intermediate shaft 8 bearing 6 and the second intermediate shaft bearing 9, the first half shaft and the second half shaft on both sides of the differential 10 are respectively rotatably arranged on the first differential bearing 7 and the second differential bearing 11, and the two ends of the first half shaft are simultaneously supported by the half shaft bearing 2 and the first differential bearing 7.

[0030] In some embodiments, the diameter of the first driven gear is larger than the diameter of the second driving gear. With this setting method, two-stage deceleration from the drive motor 12 to the differential 10 can be achieved, thereby increasing the wheel-end driving torque. Preferably, the reduction ratio from the drive motor 12 to the differential 10 can be greater than 10.

[0031] The coaxial electric drive provided by the embodiments of the present application has the following energy transfer path: The external power supply exchanges energy with the motor controller 13 through the DC high-voltage interface 15; the motor controller 13 exchanges energy with the drive motor 12 through the three-phase connection port 14; the drive motor 12 converts electrical energy and mechanical energy; the rotor of the drive motor 12 outputs or inputs mechanical work through the motor shaft 4; the motor shaft 4 drives the first driving gear, and the power is transmitted from the first driving gear to the first driven gear of the intermediate shaft 8, then from the first driven gear to the second driving gear, then from the second driving gear to the second driven gear, and then from the second driven gear to the differential 10. In this process, the rotational speed and torque can be transmitted bidirectionally; the differential 10 transmits the rotational speed and torque to the first half shaft 1 and the second half shaft, and the first half shaft 1 and the second half shaft then transmit the rotational speed and torque to the wheel end.

[0032] According to the second aspect of the present application, the embodiments of the present application provide a drive system, and the drive system includes the coaxial electric drive provided by any embodiment of the present application.

[0033] According to the third aspect of the present application, the embodiments of the present application provide a vehicle, and the vehicle includes the coaxial electric drive provided by any embodiment of the present application.

[0034] Based on the above embodiments of the present application, in the case of no explicit negation or conflict, the technical features of one embodiment can be beneficially combined with one or more other embodiments.

[0035] Although some specific embodiments of the present application have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for the purpose of illustration and not for the purpose of limiting the scope of the present application. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be equivalently replaced without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A coaxial electric drive, characterized in that: include: A driving motor, wherein a first driving gear is arranged on a motor shaft of the driving motor; A differential, wherein the differential is coaxially arranged with the drive motor, and a second driven gear is arranged on the differential, the second driven gear is arranged in parallel with the first driving gear, and the center of the second driven gear and the first driving gear is located on a straight line where the motor shaft is located; A plurality of intermediate shafts are arranged along the circumferential direction of the first driving gear and the second driven gear and are parallel to the motor shaft, and the positions of the plurality of intermediate shafts relative to the stator of the drive motor are kept fixed, wherein a first driven gear and a second driving gear are fixedly arranged on each of the intermediate shafts, the first driven gear and the second driving gear are arranged along the axial direction of the intermediate shaft, the first driven gear is meshed with the first driving gear, and the second driving gear is meshed with the second driven gear.

2. The coaxial electric drive according to claim 1, characterized in that: The plurality of intermediate shafts are evenly distributed along the circumference of the first driving gear and the second driven gear.

3. The coaxial electric drive according to claim 1, characterized in that: Also includes: The number of the intermediate shafts is three.

4. The coaxial electric drive according to claim 1, characterized in that: Also includes: A motor controller is connected to the driving motor.

5. The coaxial electric drive according to claim 4, characterized in that: The motor controller is annular and is coaxially arranged with the driving motor.

6. The coaxial electric drive according to claim 4, characterized in that: The motor controller is provided with a DC high voltage interface and a three-phase wiring port, the DC high voltage interface is used to connect to an external DC high voltage power supply, and the three-phase wiring port is connected to the drive motor.

7. The coaxial electric drive according to claim 1, characterized in that: The motor shaft is provided with a passage penetrating the motor shaft along its axial direction; The first half shaft and the second half shaft are respectively connected to each other on both sides of the differential. The first half shaft passes through the channel and is used to transmit power to the wheels on one side of the coaxial electric drive, and the second half shaft is used to transmit power to the wheels on the other side of the coaxial electric drive.

8. The coaxial electric drive according to claim 1, characterized in that: The diameter of the first driven gear is greater than the diameter of the second driving gear.

9. A drive system, characterized in that: Comprising a coaxial electric drive as described in any one of claims 1-8.

10. An automobile, characterized in that: Comprising a coaxial electric drive as described in any one of claims 1-8.

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