Coaxial driving device for motor vehicle

Abstract

The invention discloses a coaxial driving device for a motor vehicle. Comprising an input shaft, a first output shaft, a second output shaft, an input sun gear, a gear ring, a first planet carrier, a first planet gear and a second planet gear, wherein the input sun gear is connected with the input shaft without relative rotation; the first planet carrier is connected with the first output shaft without relative rotation; the first planet gear is arranged on a first planet carrier, the second planet gear is arranged on a second planet carrier, the third planet gear and the second planet gear are coaxially arranged and are connected in a non-relative-rotation mode, and the output sun gear is meshed with the third planet gear and is connected with a second output shaft in a non-relative-rotation mode. And the second planet carrier is fixedly arranged. According to the coaxial driving device for the motor vehicle, on the premise that the speed reduction and differential functions of the driving device are achieved, the power transmission path is optimized, the number of parts is reduced, and cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile electric drive systems, and in particular, the present invention relates to a coaxial drive device for a motor vehicle. Background Art

[0002] Patent with publication number DE 10 2013 215 877 B4 discloses a coaxial drive device, which consists of three single-row planetary gear mechanisms, namely a first single-row planetary gear mechanism, a second single-row planetary gear mechanism and a third single-row planetary gear mechanism, the first single-row planetary gear mechanism includes a first sun gear, a first planetary gear set, a first planet carrier and a first ring gear, the second single-row planetary gear mechanism includes a second sun gear, a second planetary gear set, a second planet carrier and a second ring gear, and the third single-row planetary gear mechanism includes a third sun gear, a third planetary gear set, a third planet carrier and a third ring gear, wherein the first planet carrier is connected to the second sun gear without relative rotation, the second planet carrier is fixed, the first ring gear is connected to the third sun gear without relative rotation, and the third ring gear is connected to the second planet carrier without relative rotation. The first single-row planetary gear mechanism diverts the input power from the first sun gear to the first planetary carrier output and the first ring gear output, and the output torque is amplified. The two output powers are then adjusted and output in terms of rotation direction and torque amplification as needed through the second single-row planetary gear mechanism and the third single-row planetary gear mechanism, thereby realizing the deceleration and differential functions of the drive device.

[0003] The epicyclic gear transmission device of the above structure has the following defects: the parts are not arranged compactly enough, the overall outer contour is large, and it occupies a large layout space.

[0004] It is desirable to provide an improved coaxial drive arrangement for a motor vehicle, particularly with respect to reducing the number of parts and lowering costs. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a coaxial drive device for a motor vehicle, the purpose of which is to reduce the number of parts and reduce costs.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a coaxial drive device for a motor vehicle, comprising an input shaft, a first output shaft, a second output shaft, an input sun gear non-rotatably connected to the input shaft, a ring gear, a first planet carrier non-rotatably connected to the first output shaft, a first planet gear arranged on the first planet carrier and meshing with the input sun gear, a second planet gear, a third planet gear coaxially arranged with the second planet gear and non-rotatably connected, and an output sun gear meshing with the third planet gear and non-rotatably connected to the second output shaft, the second planet gear and the third planet gear are arranged on the second planet carrier, the second planet carrier is fixedly arranged, and the ring gear is a common ring gear of the first planet gear and the second planet gear, that is, the ring gear meshes with the first planet gear and the second planet gear.

[0007] The number of the second planetary gear and the third planetary gear is no less than 2.

[0008] The number of the first planetary gears is no less than 2.

[0009] The first planetary carrier is provided with a first planetary gear shaft, and the first planetary gear is provided on the first planetary gear shaft.

[0010] The second planetary gear and the third planetary gear are fixedly connected to form an integral whole.

[0011] The second planetary carrier is provided with a second planetary gear shaft, and the second planetary gear and the third planetary gear are provided on the second planetary gear shaft.

[0012] The coaxial drive device for a motor vehicle further comprises a housing, and the second planet carrier is fixedly connected to the housing.

[0013] The input shaft is coaxially arranged with the first output shaft and the second output shaft.

[0014] The diameter of the first planetary gear is greater than the diameter of the second planetary gear.

[0015] The present invention is used for a coaxial drive device for a motor vehicle, which optimizes the power transmission path, reduces the number of parts and reduces the cost while realizing the deceleration and differential functions of the drive device. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] This specification includes the following drawings, which show the following contents:

[0017] Figure 1 It is a transmission diagram of a coaxial drive device for a motor vehicle of the present invention;

[0018] Figure 2 It is a gear meshing diagram of a coaxial drive device for a motor vehicle;

[0019] Markings in the figure are: 1, input shaft; 2, input sun gear; 3, first planetary carrier; 4, first planetary gear shaft; 5, first planetary gear; 6, ring gear; 7, second planetary gear; 8, housing; 9, second planetary carrier; 10, second planetary gear shaft; 11, third planetary gear; 12, output sun gear; 13, second output shaft; 14, first output shaft. DETAILED DESCRIPTION

[0020] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and facilitating its implementation.

[0021] It should be noted that, in the following embodiments, the “first”, “second” and “third” mentioned do not represent an absolute distinction in structure and / or function, nor do they represent a sequence of execution, but are merely for the convenience of description.

[0022] like Figure 1 and Figure 2 As shown, the present invention provides a coaxial drive device for a motor vehicle, comprising an input shaft 1, a first output shaft 14, a second output shaft 13, an input sun gear 2 non-rotatably connected to the input shaft 1, a ring gear 6, a first planet carrier 3 non-rotatably connected to the first output shaft 14, a first planet gear 5 arranged on the first planet carrier 3 and meshing with the input sun gear 2, a second planet gear 7, a third planet gear 11 coaxially arranged with the second planet gear 7 and non-rotatably connected, and an output sun gear 12 meshing with the third planet gear 11 and non-rotatably connected to the second output shaft 13, the ring gear 6 meshes with the first planet gear 5 and the second planet gear 7 at the same time, the second planet gear 7 and the third planet gear 11 are arranged on the second planet carrier 9, and the second planet carrier 9 is fixed.

[0023] Specifically, if Figure 1 and Figure 2 As shown, the coaxial drive device for vehicles of the present invention optimizes the power transmission path compared with the prior art while realizing the deceleration and differential functions of the drive device, thereby reducing the number of parts. Furthermore, by sharing parts and using only one ring gear component, the number of parts and costs are further reduced.

[0024] like Figure 1 and Figure 2As shown, a plurality of first planetary gears 5 are provided, a first planetary gear shaft 4 is provided on the first planetary carrier 3, the first planetary gear 5 is provided on the first planetary gear shaft 4, the first planetary gears 5 are distributed around the outside of the input sun gear 2, the first planetary gear shaft 4 is relatively fixedly connected to the first planetary carrier 3, the first planetary gear 5 is arranged on the first planetary gear shaft 4 so as to be relatively free to rotate, the first planetary gear 5 and the first planetary gear shaft 4 are arranged in pairs and the number is not less than 2. The input sun gear 2 is coaxially arranged with the input shaft 1, and the input sun gear 2 rotates synchronously with the input shaft 1. The first planetary carrier 3 is connected to the first output shaft 14 without relative rotation to output power.

[0025] like Figure 1 and Figure 2 As shown, the second planetary gear 7 and the third planetary gear 11 are coaxially arranged, and the second planetary gear 7 and the third planetary gear 11 are fixedly connected as one. The second planetary gear shaft 10 is arranged on the second planetary carrier 9, and the second planetary gear 7 and the third planetary gear 11 are arranged on the second planetary gear shaft 10. The second planetary gear shaft 10 is relatively fixedly connected to the second planetary carrier 9, and the second planetary gear 7 and the third planetary gear 11 are relatively freely rotatable on the second planetary gear shaft 10. The number of the second planetary gear 7, the third planetary gear 11 and the second planetary gear shaft 10 is the same and is not less than 2 respectively.

[0026] like Figure 1 and Figure 2 As shown, the coaxial drive device for a motor vehicle of the present invention further comprises a housing 8 , and a second planet carrier 9 is fixedly connected to the housing 8 .

[0027] like Figure 1 and Figure 2 As shown, the gear ring 6 is a common gear ring, that is, the gear ring 6 meshes with the first planetary gear 5 and the second planetary gear 7, the first planetary gear 5 and the second planetary gear 7 are located on the inner side of the gear ring 6, and the axis of the first planetary gear 5 and the axis of the second planetary gear 7 are parallel. The gear ring 6 is a large-sized part in the planetary gear mechanism, and the processing technology of the internal gear leads to a high cost. In the present invention, the first planetary gear 5 and the second planetary gear 7 share one gear ring 6, which further reduces the number of gear rings 6, and achieves the advantages of further reducing the number of parts and reducing costs.

[0028] like Figure 1 and Figure 2 As shown, the input shaft 1 is coaxially arranged with the first output shaft 14 and the second output shaft 13. The diameter of the second planetary gear 7 is greater than the diameter of the third planetary gear 11.

[0029] The power transmission description and working principle of the coaxial drive device for motor vehicles of the present invention are as follows:

[0030] The input power is connected through the input shaft 1 and transmitted to the input sun gear 2. The torque of the input power is set to: T. The input power is usually provided by the motor. The input power is diverted to the first planetary carrier 3 and the ring gear 6. The output torque on the first planetary carrier 3 is: k*T (the torque is amplified by the planetary gear mechanism, k is the amplification factor, and the value of k is usually greater than 2.5), and the output torque of the ring gear 6 is: -(k-1)*T (the negative sign indicates that the torque direction is opposite to the input power torque direction);

[0031] Since the first output shaft 14 is not connected to the first planet carrier 3 in a relative rotational connection, the output torque of the first output shaft 14 is also: k*T;

[0032] The power diverted to the ring gear 6 is then transmitted to the second output shaft 13 through the second planetary gear 7, the third planetary gear 11, and the output sun gear 12 for output. By setting the number of teeth of the second planetary gear 7, the third planetary gear 11, and the output sun gear 12, the transmission ratio (i.e., the torque amplification factor) from the ring gear 6 to the output sun gear 12 is preferably set to: -k / (k-1);

[0033] The output torque of the second output shaft 13 , that is, the preferred output torque of the output sun gear 12 is: −(k−1)*T*(−k / (k−1))=k*T, which is equal to or close to the output torque of the first output shaft 14 .

[0034] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A coaxial drive device for a motor vehicle, comprising an input shaft, a first output shaft, a second output shaft, an input sun gear non-rotatably connected to the input shaft, a ring gear, a first planet carrier non-rotatably connected to the first output shaft, a first planet gear disposed on the first planet carrier and meshing with the input sun gear, a second planet gear, a third planet gear coaxially arranged with the second planet gear and non-rotatably connected, and an output sun gear meshing with the third planet gear and non-rotatably connected to the second output shaft, wherein the second planet gear and the third planet gear are disposed on the second planet carrier, and the second planet carrier is fixedly disposed, characterized in that: The ring gear is a common ring gear of the first planetary gear and the second planetary gear, that is, the ring gear is meshed with the first planetary gear and the second planetary gear.

2. The coaxial drive device for a motor vehicle according to claim 1, characterized in that: The number of the second planetary gear and the third planetary gear is no less than 2.

3. The coaxial drive device for a motor vehicle according to claim 1, characterized in that: The number of the first planetary gears is no less than 2.

4. A coaxial drive device for a motor vehicle according to any one of claims 1 to 3, characterized in that: The first planetary carrier is provided with a first planetary gear shaft, and the first planetary gear is provided on the first planetary gear shaft.

5. The coaxial drive device for a motor vehicle according to any one of claims 1 to 3, characterized in that: The second planetary gear and the third planetary gear are fixedly connected to form an integral whole.

6. The coaxial drive device for a motor vehicle according to any one of claims 1 to 3, characterized in that: The second planetary carrier is provided with a second planetary gear shaft, and the second planetary gear and the third planetary gear are provided on the second planetary gear shaft.

7. A coaxial drive device for a motor vehicle according to any one of claims 1 to 3, characterized in that: The invention also includes a housing, wherein the second planet carrier is fixedly connected to the housing.

8. The coaxial drive device for a motor vehicle according to any one of claims 1 to 3, characterized in that: The input shaft is coaxially arranged with the first output shaft and the second output shaft.

9. The coaxial drive device for a motor vehicle according to claim 8, characterized in that: The diameter of the second planetary gear is greater than the diameter of the third planetary gear.

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