An electric drive axle large speed ratio planetary gear transmission

Abstract

The utility model provides a kind of electric drive bridge big speed ratio planetary gear box, it is small, and transmission speed ratio is big, high strength, transmission efficiency is high.It includes: a group of NW planetary gear, it includes first sun gear shaft, first planet carrier, the first sun gear shaft is input shaft, the output end of the NW planetary gear is connected with main reduction tooth;Two block NGW planetary gears, it includes high-low block shifting assembly, NGW planetary gear, the NGW planetary gear includes second sun gear shaft, second planet carrier, the second sun gear shaft is fixedly sleeved with transmission gear, the transmission gear is the power input end of NGW planetary gear, the second planet carrier is the power output end of NGW planetary gear;And differential, it includes shell, two output half shafts.

Description

Technical Field

[0001] This utility model relates to the technical field of electric drive axles for new energy vehicles, specifically a high-ratio planetary gearbox for electric drive axles. Background Technology

[0002] The electric drive axle is an electromechanical integrated drive system designed for electric vehicles, featuring advantages such as high integration, small size, and low energy consumption. As a core component of electric vehicles, its performance directly affects the power and economy of the vehicle.

[0003] The electric drive axle mainly consists of a motor, inverter, and gearbox. With the increasing penetration rate of new energy trucks, the application of electric drive axles is becoming more and more widespread, and heavy-duty truck electric drive axles are constantly emerging. The existing heavy-duty truck electric drive axles use a large gearbox structure with four, five, or even six transmission stages for low-speed transmission. The large size of the gearbox means that the design is relatively difficult, thus there is an urgent need to develop an electric drive axle gearbox with a smaller size, a larger speed ratio, and higher efficiency. Utility Model Content

[0004] To address the aforementioned problems, this utility model provides an electric drive axle high-ratio planetary gearbox, which is small in size and has a large transmission ratio, high strength, and high transmission efficiency.

[0005] A high-ratio planetary gearbox with an electric drive axle, characterized in that it comprises: A set of NW planetary gears includes a first sun gear shaft and a first planet carrier. The first sun gear shaft is an input shaft, and the output end of the NW planetary gear set is connected to a main reduction gear. A two-speed NGW planetary gear set includes a high / low gear shifting assembly and an NGW planetary gear set. The NGW planetary gear set includes a second sun gear shaft and a second planet carrier. A transmission gear is fixedly mounted on the second sun gear shaft. The transmission gear is the power input end of the NGW planetary gear set, and the second planet carrier is the power output end of the NGW planetary gear set. And the differential, which includes a housing and two output half-shafts; The drive motor is connected to the first sun gear shaft of the NW planetary gear set. The first planetary carrier transmits power to the second sun gear shaft of the two-speed NW planetary gear set through the main reduction gear and the transmission gear. Finally, the second planetary carrier outputs power to the housing of the differential. The differential outputs power through the output half shaft. The high and low gear shifting assembly is used to switch the high or low gear power output of the NW planetary gear set. The high / low gear shifting component is an automatic shifting component.

[0006] Its further features are: The NW planetary gear set includes a first sun gear shaft, a first sun gear, a first planet carrier, a first planet gear set, and a first ring gear. The first ring gear is fixed in position. The first planet carrier includes two first gear carriers on both sides and a plurality of first planet gear shafts. The input end of the first sun gear shaft is connected to the output end of the drive motor. The first sun gear is fixedly mounted on the first sun gear shaft. Each first planet gear shaft is fitted with a corresponding first planet gear set. The first planet gear set includes a gear that meshes with the first sun gear and a gear that meshes with the first ring gear. The radial center of the first gear carrier on the side away from the drive motor protrudes outward to form a main output shaft. The main output shaft is fixedly mounted with the main reduction gear. Preferably, the first planetary gear set includes a first gear meshing with a first sun gear and a second gear meshing with a first ring gear; Alternatively, the first planetary gear set may be a single first planetary gear, in which the first planetary gear simultaneously meshes with the first sun gear and the first ring gear. The NGW planetary gear set includes a second sun gear shaft, a second planet carrier, a second sun gear, a second ring gear, and several second planet gears. A transmission gear is fitted at the input end of the second sun gear shaft, and a second sun gear is fitted at the output end of the second sun gear shaft. The second planet carrier is fixedly mounted on the outer circumference of the non-half-shaft output end of the differential housing. Several second planet gears are arranged around the second planet carrier near one of the output half-shafts. A second ring gear is arranged around the outer circumference of the second planet gears. The second planet gears are meshed with the second ring gear and the second sun gear, respectively. The corresponding output half-shafts are arranged through the hollow second sun gear shaft. The high / low gear shifting assembly includes a high / low gear shifting sleeve, a fixed engagement gear, a planetary carrier engagement gear, and a connecting frame. The high / low gear shifting sleeve is arranged between the fixed engagement gear and the planetary carrier engagement gear. The fixed engagement gear is fixedly connected to the electric drive axle housing and is arranged towards the high / low gear shifting sleeve. The end of the second planetary carrier furthest from the differential is provided with a planetary carrier engagement gear, which is arranged towards the high / low gear shifting sleeve. The high / low gear shifting sleeve is connected to the second gear ring through the connecting frame. The high / low gear shifting sleeve is axially movable along the connecting frame. The axial movement of the high / low gear shifting sleeve switches between high and low gears.

[0007] By adopting the structure of this utility model, a single NW planetary gear set is used to achieve a larger speed ratio transmission. Compared with commonly used three-stage or higher gear transmissions, this NW planetary gear set is smaller in size, has a larger speed ratio, and higher efficiency, making it more suitable for placement in the electric drive axle location. Furthermore, through a pair of gear pairs connected in series with a two-speed NGW planetary gear set, a two-speed switching transmission structure is achieved. The two-speed NGW planetary gear set is located next to the differential, and through an automatic shifting mechanism, automatic high and low gears are achieved. The low gear is a three-stage transmission, and the high gear NGW is a direct drive, resulting in a shorter transmission path and higher transmission efficiency. Compared with commonly used three-stage or higher transmission electric drive axle transmissions, this design achieves the advantages of a smaller transmission size, higher efficiency, simpler transmission structure, lower cost, larger low gear ratio, smaller high gear ratio, and automatic high and low gear shifting. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the framework of a specific embodiment of the present utility model; The names corresponding to the serial numbers in the diagram are as follows: NW planetary gear set 10, first sun gear shaft 11, first planetary carrier 12, first gear carrier 121, first planetary gear shaft 122, first sun gear 13, first planetary gear set 14, first gear 141, second gear 142, first ring gear 15, two-speed NGW planetary gear set 20, differential 30, housing 31, output half shaft 32, main reduction gear 40, high / low gear shift assembly 50, high / low gear shift sleeve 51, fixed engagement gear 52, planetary carrier engagement gear 53, connecting frame 54, NGW planetary gear set 60, second sun gear shaft 61, second planetary carrier 62, second sun gear 63, second ring gear 64, second planetary gear 65, transmission gear 70, drive motor 80, main output shaft 90. Detailed Implementation

[0009] A high-ratio planetary gearbox with an electric drive axle, see Figure 1 It includes an NW planetary gear set 10, a two-speed NGW planetary gear set 20, and a differential 30; The NW planetary gear set 10 includes a first sun gear shaft 11 and a first planet carrier 12. The first sun gear shaft 11 is the input shaft, and the output end of the NW planetary gear set 10 is connected to a main reduction gear 40. The two-speed NGW planetary gear set 20 includes a high-low gear shifting assembly 50 and an NGW planetary gear set 60. The NGW planetary gear set 60 includes a second sun gear shaft 61 and a second planet carrier 62. A transmission gear 70 is fixedly mounted on the second sun gear shaft 61. The transmission gear 70 is the power input end of the NGW planetary gear set 60, and the second planet carrier 62 is the power output end of the NGW planetary gear set 60. The differential 30 includes a housing 31 and two output half-shafts 32; The drive motor 80 is connected to the first sun gear shaft 11 of the NW planetary gear set 10. The first planet carrier 12 transmits power to the second sun gear shaft 61 of the two-speed NW planetary gear set 20 through the main reduction gear 40 and the transmission gear 70. Finally, the second planet carrier 62 outputs power to the housing 31 of the differential 30. The differential 30 outputs power through the output half shaft 32. The high and low gear shifting assembly 50 is used to switch the high or low gear power output of the NW planetary gear set 60. The high / low gear shifting assembly 50 is an automatic shifting assembly.

[0010] In a specific embodiment, the NW planetary gear set 10 includes a first sun gear shaft 11, a first planet carrier 12, a first sun gear 13, a first planetary gear set 14, and a first ring gear 15. The first ring gear 15 is fixed in position. The first planet carrier 12 includes two first gear carriers 121 on both sides and a plurality of first planetary gear shafts 122. The input end of the first sun gear shaft 11 is connected to the output end of the drive motor 80. The first sun gear 13 is fixedly mounted on the first sun gear shaft 11. Each first planetary gear shaft 122 is fitted with a corresponding first planetary gear set 14. The first planetary gear set 14 includes a gear that meshes with the first sun gear 13 and a gear that meshes with the first ring gear 15. The radial center of the first gear carrier 121 on the side away from the drive motor 80 protrudes outward to form a main output shaft 90. A main reduction gear 40 is fixedly mounted on the main output shaft 90. In a specific implementation, the first planetary gear set 14 includes a first gear 141 that meshes with the first sun gear 13 and a second gear 142 that meshes with the first ring gear 15. The NGW planetary gear set 60 includes a second sun gear shaft 61, a second planet carrier 62, a second sun gear 63, a second ring gear 64, and several second planet gears 65. The input end of the second sun gear shaft 61 is fitted with a transmission gear 70, and the output end of the second sun gear shaft 61 is fitted with a second sun gear 63. The outer circumference of the non-half-shaft output end of the differential housing 31 is fixedly mounted with a second planet carrier 62. Several second planet gears 65 are arranged around the second planet carrier 62 near one of the output half-shafts 32. The outer circumference of the second planet gears 65 is arranged with a second ring gear 64. The second planet gears 65 are meshed with the second ring gear 64 and the second sun gear 63 respectively. The corresponding output half-shafts 32 are arranged through the hollow second sun gear shaft 61. The high / low gear shifting assembly 50 includes a high / low gear shifting sleeve 51, a fixed engagement gear 52, a planetary carrier engagement gear 53, and a connecting frame 54. The high / low gear shifting sleeve 51 is arranged between the fixed engagement gear 52 and the planetary carrier engagement gear 53. The fixed engagement gear 52 is fixedly connected to the electric drive axle housing and is arranged towards the high / low gear shifting sleeve 51. The end of the second planetary carrier 62 away from the differential 30 is provided with the planetary carrier engagement gear 53, which is arranged towards the high / low gear shifting sleeve 51. The high / low gear shifting sleeve 51 is connected to the second gear ring 64 through the connecting frame 54. The high / low gear shifting sleeve 51 is axially movable along the connecting frame 64. The axial movement of the high / low gear shifting sleeve 51 switches between high and low gears.

[0011] The high / low gear shifting sleeve 51 is axially movable along the connecting frame 54. The high / low gear shifting sleeve 51 moves axially to switch between high and low gears. When the high / low gear shifting sleeve 51 is engaged with the fixed meshing teeth 52, the NGW planetary gear set 60 is in the low gear engagement state. When the high / low gear shifting sleeve 51 is engaged with the planetary carrier 53, the NGW planetary gear set 60 is in the high gear engagement state. The NGW planetary gear set 60 is equipped with two outputs to achieve low speed and high torque, and high speed and high transmission efficiency, effectively improving power and economy.

[0012] The principle is as follows: Using an NW planetary gear set, a larger speed ratio transmission is achieved. Compared to commonly used three-stage or higher gear transmissions, the NW planetary gear set is smaller, has a larger speed ratio, and higher efficiency, making it more suitable for placement in the electric drive axle location. Furthermore, through a pair of gears connected in series with a two-speed NGW planetary gear set, a two-speed switching transmission structure is achieved. With a two-speed NGW planetary gear set positioned next to the differential, an automatic shifting mechanism enables automatic high and low gear shifting. The low gear is a three-stage transmission, while the high gear (NGW) is a direct drive. This two-stage transmission results in a shorter transmission path and higher transmission efficiency. Compared to commonly used three-stage or higher transmission electric drive axle transmissions, it achieves the advantages of a smaller transmission size, higher efficiency, simpler transmission structure, lower cost, a larger low gear ratio, a smaller high gear ratio, and automatic high and low gear shifting.

[0013] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0014] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A high-ratio planetary gearbox with an electric drive axle, characterized in that, It includes: A set of NW planetary gears, including a first sun gear shaft and a first planet carrier, wherein the first sun gear shaft is an input shaft and the output end of the NW planetary gears is connected to a main reduction gear; A two-speed NGW planetary gear set includes a high / low gear shifting assembly and an NGW planetary gear set. The NGW planetary gear set includes a second sun gear shaft and a second planet carrier. A transmission gear is fixedly mounted on the second sun gear shaft. The transmission gear is the power input end of the NGW planetary gear set, and the second planet carrier is the power output end of the NGW planetary gear set. And the differential, which includes a housing and two output half-shafts; The drive motor is connected to the first sun gear shaft of the NW planetary gear set. The first planetary carrier transmits power to the second sun gear shaft of the two-speed NW planetary gear set through the main reduction gear and the transmission gear. Finally, the second planetary carrier outputs power to the housing of the differential. The differential outputs power through the output half shaft. The high and low gear shifting assembly is used to switch the high or low gear power output of the NW planetary gear set. The high / low gear shifting component is an automatic shifting component.

2. The electric drive axle high-ratio planetary gearbox according to claim 1, characterized in that: The NW planetary gear set includes a first sun gear shaft, a first sun gear, a first planet carrier, a first planet gear set, and a first ring gear. The first ring gear is fixed in position. The first planet carrier includes two first gear carriers on both sides and several first planet gear shafts. The input end of the first sun gear shaft is connected to the output end of the drive motor. The first sun gear is fixedly mounted on the first sun gear shaft. Each first planet gear shaft is fitted with a corresponding first planet gear set. The first planet gear set includes a gear that meshes with the first sun gear and a gear that meshes with the first ring gear. The radial center of the first gear carrier on the side away from the drive motor protrudes outward to form a main output shaft. The main reduction gear is fixedly mounted on the main output shaft.

3. The electric drive axle high-ratio planetary gearbox according to claim 2, characterized in that: The first planetary gear set includes a first gear meshing with a first sun gear and a second gear meshing with a first ring gear.

4. The electric drive axle high-ratio planetary gearbox according to claim 2, characterized in that: The first planetary gear set is a single first planetary gear, which simultaneously meshes with the first sun gear and the first ring gear.

5. The electric drive axle high-ratio planetary gearbox according to claim 2, characterized in that: The NGW planetary gear set includes a second sun gear shaft, a second planet carrier, a second sun gear, a second ring gear, and several second planet gears. A transmission gear is fitted at the input end of the second sun gear shaft, and a second sun gear is fitted at the output end of the second sun gear shaft. The second planet carrier is fixedly mounted on the outer circumference of the non-half-shaft output end of the differential housing. Several second planet gears are arranged around the second planet carrier near one of the output half-shafts. A second ring gear is arranged around the outer circumference of the second planet gears. The second planet gears are meshed with the second ring gear and the second sun gear, respectively. The corresponding output half-shafts are arranged through the hollow second sun gear shaft.

6. The electric drive axle high-ratio planetary gearbox according to claim 5, characterized in that: The high / low gear shifting assembly includes a high / low gear shifting sleeve, a fixed engagement gear, a planetary carrier engagement gear, and a connecting frame. The high / low gear shifting sleeve is arranged between the fixed engagement gear and the planetary carrier engagement gear. The fixed engagement gear is fixedly connected to the electric drive axle housing and is arranged towards the high / low gear shifting sleeve. The end of the second planetary carrier furthest from the differential is provided with a planetary carrier engagement gear, which is arranged towards the high / low gear shifting sleeve. The high / low gear shifting sleeve is connected to the second gear ring through the connecting frame. The high / low gear shifting sleeve is axially movable along the connecting frame. The axial movement of the high / low gear shifting sleeve switches between high and low gears.

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