Integrated electric drive axle with three-gear speed change function

Abstract

The utility model discloses an integrated electric drive axle with a three-gear speed change function. The integrated electric drive axle comprises a drive motor gear shaft, a driving gear shaft, a gear shifting gear shaft and a differential mechanism assembly. Included angles between the connecting lines of the center of the differential assembly and the centers of the driving motor gear shaft, the driving gear shaft and the shifting gear shaft and the horizontal direction are A, B and C; the driving gear shaft is connected with a first-gear driving gear, a second-gear driving gear and a third-gear driving gear; an output gear, a first gear shifting execution mechanism, a second gear shifting execution mechanism, a rotatable first-gear driven gear, a rotatable second-gear driven gear and a rotatable third-gear driven gear are arranged on the gear shifting gear shaft; a gear on a gear shaft of the driving motor is meshed with the third-gear driving gear, and the first-gear driving gear, the second-gear driving gear and the third-gear driving gear are selectively meshed with the first-gear driven gear, the second-gear driven gear and the third-gear driven gear under the driving of the first gear shifting executing mechanism and the second gear shifting executing mechanism. The structural layout is compact, and the running reliability of a transmission system is improved.

Description

Technical Field

[0001] This utility model relates to the field of electric drive vehicle axle technology, specifically to an integrated electric drive vehicle axle with three-speed transmission function. Background Technology

[0002] The power system of new energy commercial vehicles mainly includes two configurations: integrated electric drive axle and central electric drive assembly. Among them, the integrated electric drive axle has a short transmission route, light weight, and excellent energy consumption level, so it has been increasingly widely used in the field of commercial vehicles. However, compared with new energy passenger vehicles, commercial vehicles have heavy loads, complex operating routes, and more diverse speed and power requirements. Therefore, multi-speed integrated electric drive axles have become the mainstream technology adopted in the development of this field.

[0003] Currently, common multi-speed integrated electric drive axles have 2-4 speed transmission functions. To realize the multi-speed transmission function of electric drive axles, the commonly used shifting method is to adjust the speed ratio by setting multiple parallel shaft shifting gear shafts or multi-stage planetary gear pairs. However, this structure has the following problems: (1) Using multiple parallel shaft shifting gear shafts to adjust the speed ratio results in a larger overall size of the transmission system and a significant increase in the weight of the front suspension of the axle, which seriously affects the structural layout of the vehicle. At the same time, the reliability of the product is greatly reduced, and it is very easy to cause axle housing deformation, oil leakage and other faults; (2) Using multi-stage planetary gear pairs to adjust the speed ratio can reduce the overall size and structure of the reducer, but its structure is relatively complex, the shifting control strategy is too complex, and the manufacturing process requirements are much higher than those of the parallel gear shaft structure, resulting in relatively high manufacturing costs, which seriously limits the promotion and application of integrated electric drive axles in the commercial vehicle field. Utility Model Content

[0004] To address the aforementioned problems in the existing technology, this utility model provides an integrated electric drive axle with a three-speed transmission function. The technical problem to be solved by this utility model is achieved through the following technical solution:

[0005] An integrated electric drive axle with three-speed transmission includes a drive motor gear shaft, a drive gear shaft, a shift gear shaft, and a differential assembly; wherein...

[0006] The angles between the lines connecting the center of the differential assembly, the center of the drive motor gear shaft, the center of the drive gear shaft, and the center of the shift gear shaft and the horizontal direction are A, B, and C, respectively, where (1-20%)C≤B≤(1+20%)C; A≥3B;

[0007] A first-speed drive gear, a second-speed drive gear, and a third-speed drive gear are fixedly connected to the drive gear shaft.

[0008] The shift gear shaft is provided with an output gear, a first shift actuator, a second shift actuator, and a first-gear driven gear, a second-gear driven gear, and a third-gear driven gear that can rotate freely along the shift gear shaft;

[0009] A drive motor gear is fixed on the drive motor gear shaft. The drive motor gear meshes with a three-speed drive gear. The first-speed drive gear can selectively mesh with the first-speed driven gear under the drive of the first shifting mechanism. The second-speed drive gear can selectively mesh with the second-speed driven gear under the drive of the second shifting mechanism. The third-speed drive gear can selectively mesh with the third-speed driven gear under the drive of the second shifting mechanism.

[0010] Furthermore, the first shift actuator includes a first splined hub and a first shift power coupling sleeve; the first splined hub is fixedly mounted on the shift gear shaft, and the first power coupling sleeve is mounted around the first splined hub and can move axially along the first splined hub.

[0011] Furthermore, the second shift actuator includes a second splined hub and a second shift power coupling sleeve; the second splined hub is fixedly mounted on the shift gear shaft, and the second power coupling sleeve is mounted around the second splined hub and can move axially along the second splined hub.

[0012] Furthermore, the first splined hub and the first shift power coupling sleeve, and the second splined hub and the second power coupling sleeve are connected by internal splines.

[0013] Furthermore, the connection between the first and second shift power coupling sleeves and the adjacent transmission gears is a spline connection or an end face tooth connection.

[0014] Furthermore, a rolling assembly is provided between the first-gear driven gear, the second-gear driven gear, the third-gear driven gear and the shift gear shaft.

[0015] Furthermore, it also includes a power take-off assembly, which includes a power engagement sleeve. The power take-off assembly engages with the three-speed drive gear through the power engagement sleeve to achieve power take-off.

[0016] The beneficial effects of this utility model are:

[0017] 1. The parallel gear shaft transmission structure is adopted. By optimizing the angle between the line connecting the center of the differential assembly, the center of the drive motor gear shaft, the center of the drive gear shaft, and the center of the shift gear shaft and the horizontal direction, the size of the transmission shaft system and the vertical arm in the horizontal direction are effectively reduced while ensuring the transmission speed ratio. The structure is simple and compact, and can alleviate the impact caused by vibration during vehicle operation, thus greatly improving the reliability of the transmission system operation and installation.

[0018] 2. By adding a drive gear shaft between the drive motor gear shaft and the shift gear shaft, and ensuring that there is always a meshing transmission relationship between the drive motor gear and the third-speed drive gear on the drive gear shaft, the gear speed can be reduced before shifting gears by the transmission between the drive motor gear and the third-speed drive gear, thus significantly reducing the gear speed during shifting. This effectively reduces shifting shock and improves smoothness when switching between first and second gear.

[0019] 3. By setting a shift gear shaft with the feature of adding and removing transmission gear pairs, the shift mode of the transmission mechanism can be switched from 2 to 4 gears through adding and removing transmission gear pairs and shifting actuators. This can meet the matching needs of different products, making the products more adaptable. At the same time, the increased application volume can significantly reduce the manufacturing cost of the products.

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the transmission structure of this utility model;

[0022] Figures 2-3 This is a schematic diagram of the structure of this utility model;

[0023] Figure 4 This is a cross-sectional structural diagram of the present invention;

[0024] Figure 5 This is a schematic diagram of the first gear transmission structure of this utility model;

[0025] Figure 6 This is a schematic diagram of the two-speed transmission structure of this utility model;

[0026] Figure 7 This is a schematic diagram of the three-speed transmission structure of this utility model;

[0027] Figure 8 This is a schematic diagram of the structure of this utility model converted into a two-speed transmission;

[0028] Figure 9 This is a schematic diagram of the structure of this utility model converted into a four-speed transmission.

[0029] Explanation of reference numerals in the attached figures:

[0030] 1-Drive motor gear shaft; 2-Drive gear shaft; 3-Shift gear shaft; 4-Differential assembly; 5-First gear drive gear; 6-Second gear drive gear; 7-Third gear drive gear; 8-Output gear; 9-First shift actuator; 10-Second shift actuator; 11-First gear driven gear; 12-Second gear driven gear; 13-Third gear driven gear; 14-Rolling assembly; 15-Drive motor gear; 16-Power take-off assembly; 17-Fourth gear transmission gear pair; 9-1-First splined hub; 9-2-First shift power coupling sleeve; 10-1-Second splined hub; 10-2-Second shift power coupling sleeve. Detailed Implementation

[0031] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0032] Please see Figures 1-9 This utility model embodiment provides an integrated electric drive axle with three-speed transmission, specifically including a drive motor gear shaft 1, a drive gear shaft 2, a shift gear shaft 3, and a differential assembly 4; wherein,

[0033] The angles between the lines connecting the center of the differential assembly 4, the center of the drive motor gear shaft 1, the center of the drive gear shaft 2, and the center of the shift gear shaft 3, and the horizontal direction are A, B, and C, respectively, where (1-20%)C≤B≤(1+20%)C; A≥3B. In this embodiment of the invention, angle A is 25°, angle B is 7.5°, and angle C is 8°.

[0034] The drive gear shaft 2 is fixedly connected to a first-gear drive gear 5, a second-gear drive gear 6, and a third-gear drive gear 7. The shift gear shaft 3 is provided with an output gear 8, a first shift actuator 9, a second shift actuator 10, and a first-gear driven gear 11, a second-gear driven gear 12, and a third-gear driven gear 13 that can rotate freely along the shift gear shaft 3. The output gear 8 is fixedly connected to the shift gear shaft 3. A rolling assembly 14 is provided between the first-gear driven gear 11, the second-gear driven gear 12, the third-gear driven gear 13 and the shift gear shaft 3. The rolling assembly 14 can be a needle roller bearing.

[0035] A drive motor gear 15 is fixed on the drive motor gear shaft 1. The drive motor gear 15 meshes with the third-speed drive gear 7. The first-speed drive gear 5 can selectively mesh with the first-speed driven gear 11 under the drive of the first shifting actuator 9. The second-speed drive gear 6 can selectively mesh with the second-speed driven gear 12 under the drive of the second shifting actuator 10. The third-speed drive gear 7 can selectively mesh with the third-speed driven gear 13 under the drive of the second shifting actuator 10, thereby realizing the adjustment of the three-speed transmission ratio.

[0036] By adopting a parallel gear shaft transmission structure, that is, the axes of the drive gear shaft 2, the shift gear shaft 3 and the drive motor gear shaft 1 are parallel, and by optimizing the angles between the drive motor gear shaft 1, the drive gear shaft 2, the shift gear shaft 3 and the differential assembly 4, the horizontal dimensions and vertical arms of the transmission shaft system are effectively reduced while ensuring the transmission ratio. That is, the distance between each gear shaft and the center of the axle (i.e., the center of the differential assembly 4) is shorter, the structure is more compact, and the reliability of the transmission system operation and its installation and fixation is greatly improved, and the overturning torque of the axle is effectively reduced.

[0037] Furthermore, it should be noted that in this embodiment of the present invention, the gear diameters and number of teeth of the first-gear drive gear 5, the second-gear drive gear 6, and the third-gear drive gear 7 on the drive gear shaft 2 increase sequentially, while the gear diameters and number of teeth of the first-gear driven gear 11, the second-gear driven gear 12, and the third-gear driven gear 13 on the shift gear shaft 3 decrease sequentially. Therefore, since there is always a meshing transmission relationship between the drive motor gear 15 and the third-gear drive gear 7, when shifting between first and second gear, the speed can be reduced first through the transmission between the drive motor gear 15 and the third-gear drive gear 7, thereby effectively reducing shift shock and improving smoothness when switching between first and second gear.

[0038] The first shift actuator 9 includes a first splined hub 9-1 and a first shift power coupling sleeve 9-2; the first splined hub 9-1 is fixedly mounted on the shift gear shaft 3, and the first power coupling sleeve is mounted on the periphery of the first splined hub 9-1 and can move axially along the first splined hub 9-1.

[0039] The second shift actuator 10 includes a second splined hub 10-1 and a second shift power coupling sleeve 10-2; the second splined hub 10-1 is fixedly mounted on the shift gear shaft 3, and the second power coupling sleeve is mounted on the periphery of the second splined hub 10-1 and can move axially along the second splined hub 10-1.

[0040] Specifically, the first splined hub 9-1 and the first shift power engagement sleeve 9-2, and the second splined hub 10-1 and the second shift power engagement sleeve 10-2 are connected by internal splines. This internal spline connection offers high reliability, a large number of transmission teeth, even pressure distribution on the tooth surfaces, and lower pressure on individual teeth, which facilitates axial sliding of the shift power engagement sleeve and enables efficient shifting.

[0041] Furthermore, the connection between the first shift power engagement sleeve 9-2 and the second shift power engagement sleeve 10-2 and the adjacent transmission gears is either a spline connection or a face gear connection. This spline connection is achieved by providing internal splines on the inner surfaces of the first shift power engagement sleeve 9-2 and the second shift power engagement sleeve 10-2, which mesh with the adjacent transmission gears; or by providing gear rings on the end faces of the first shift power engagement sleeve 9-2 and the second shift power engagement sleeve 10-2, which mesh with the adjacent transmission gears. That is, the first shift power engagement sleeve 9-2 and the first gear driven gear 11 can be connected via a spline connection or a face gear connection, and the second shift power engagement sleeve 10-2 and the second gear driven gear 12 or the third gear driven gear 13 can be connected via a spline connection or a face gear connection. The spline connection provides high load-bearing capacity and smooth shifting; while the face gear connection also provides high load-bearing capacity and high shifting efficiency.

[0042] Furthermore, the electric drive axle also includes a power take-off (PTO) assembly 16, which includes a power engagement sleeve. The drive assembly uses this sleeve to engage its internal gears with the three-speed drive gear 7, thus achieving external power take-off. The power can be switched on or off depending on the actual operating conditions. The PTO assembly 16 facilitates power take-off from different external mechanisms and is unaffected by the shape of the PTO interface, thus meeting a wider range of application scenarios. By ensuring that the PTO's meshing gear, the drive motor gear 15, and the three gears on the shift gear shaft 3 all mesh with the gears on the drive gear shaft 2, the rotational torque can be effectively balanced, resulting in greater axle stability.

[0043] Furthermore, when the first shift actuator 9 and its left-side first-gear drive gear 5 and first-gear driven gear 11 are removed, the integrated electric drive axle can achieve two-gear transmission mode switching; when a fourth-gear transmission gear pair 17 is added to the right side of the first shift actuator 9, four-gear transmission mode switching can be achieved.

[0044] Specifically, the power transmission route of this utility model in the three-speed transmission mode is as follows:

[0045] I. Gear: such as Figure 5As shown, the second shift power engagement sleeve 10-2 is centrally located, that is, in the middle of two adjacent transmission gears, and has no transmission relationship with either of them. The first shift power engagement sleeve 9-2 is on the left. At this time, the first gear driven gear 11 is fixedly connected to the shift gear shaft 3 through the first shift power engagement sleeve 9-2. The torque generated by the drive motor is transmitted to the third gear drive gear 7 through the drive motor gear 15 on the drive motor gear shaft 1, and then the power is transmitted to the shift gear shaft 3 through the meshing transmission of the first gear drive gear 5 and the first gear driven gear 11. Then the power is output to the differential assembly 4 through the output gear 8, and then the differential assembly 4 distributes the power to the left and right wheel sides as needed.

[0046] Second gear: such as Figure 6 As shown, the second shift power engagement sleeve 10-2 is positioned on the right, and the first shift power engagement sleeve 9-2 is positioned in the middle. At this time, the second-gear driven gear 12 is fixedly connected to the shift gear shaft 3 through the second shift power engagement sleeve 10-2. The torque generated by the drive motor is transmitted to the third-gear drive gear 7 through the drive motor gear 15 on the drive motor gear shaft 1, and then the power is transmitted to the shift gear shaft 3 through the meshing transmission of the second-gear drive gear 6 and the second-gear driven gear 12. Then, the power is output to the differential assembly 4 through the output gear 8, and then the power is distributed to the left and right wheel sides as needed through the differential assembly 4.

[0047] Gear III: such as Figure 7 As shown, the second shift power engagement sleeve 10-2 is positioned on the left, and the first shift power engagement sleeve 9-2 is positioned in the middle. At this time, the third-speed driven gear 13 is fixedly connected to the shift gear shaft 3 through the second shift power engagement sleeve 10-2. The torque generated by the drive motor is transmitted to the third-speed driving gear 7 through the drive motor gear 15 on the drive motor gear shaft 1. Then, the power is transmitted to the shift gear shaft 3 through the meshing transmission between the third-speed driving gear 7 and the third-speed driven gear 13. The power is then output to the differential assembly 4 through the output gear 8. Finally, the power is distributed to the left and right wheel sides as needed through the differential assembly 4.

[0048] It should be noted that the positions of the first gear pair (including the first gear drive gear 5 and the first gear driven gear 11), the second gear pair (including the second gear drive gear 6 and the second gear driven gear 12), and the third gear pair (including the third gear drive gear 7 and the third gear driven gear 13) can be adjusted according to specific needs by changing the diameter and number of teeth of the corresponding gears to achieve the corresponding gear speed. This utility model embodiment only provides one specific implementation method.

[0049] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. An integrated electric drive axle with three-speed transmission, characterized in that, This includes the drive motor gear shaft, the drive gear shaft, the shift gear shaft, and the differential assembly; among which, The angles between the lines connecting the center of the differential assembly, the center of the drive motor gear shaft, the center of the drive gear shaft, and the center of the shift gear shaft and the horizontal direction are A, B, and C, respectively, where (1-20%)C≤B≤(1+20%)C; A≥3B; A first-speed drive gear, a second-speed drive gear, and a third-speed drive gear are fixedly connected to the drive gear shaft. The shift gear shaft is provided with an output gear, a first shift actuator, a second shift actuator, and a first-gear driven gear, a second-gear driven gear, and a third-gear driven gear that can rotate freely along the shift gear shaft; A drive motor gear is fixed on the drive motor gear shaft. The drive motor gear meshes with a three-speed drive gear. The first-speed drive gear can selectively mesh with the first-speed driven gear under the drive of the first shifting mechanism. The second-speed drive gear can selectively mesh with the second-speed driven gear under the drive of the second shifting mechanism. The third-speed drive gear can selectively mesh with the third-speed driven gear under the drive of the second shifting mechanism.

2. The integrated electric drive axle with three-speed transmission function according to claim 1, characterized in that, The first shift actuator includes a first splined hub and a first shift power coupling sleeve; the first splined hub is fixedly mounted on the shift gear shaft, and the first power coupling sleeve is mounted around the first splined hub and can move axially along the first splined hub.

3. The integrated electric drive axle with three-speed transmission function according to claim 2, characterized in that, The second shift actuator includes a second splined hub and a second shift power coupling sleeve; the second splined hub is fixedly mounted on the shift gear shaft, and the second power coupling sleeve is mounted around the second splined hub and can move axially along the second splined hub.

4. The integrated electric drive axle with three-speed transmission function according to claim 3, characterized in that, The first splined hub and the first shift power coupling sleeve, and the second splined hub and the second power coupling sleeve are connected by internal splines.

5. The integrated electric drive axle with three-speed transmission function according to claim 3, characterized in that, The connection between the first and second shift power coupling sleeves and the adjacent transmission gears is a spline connection or an end face tooth connection.

6. The integrated electric drive axle with three-speed transmission function according to claim 1, characterized in that, A rolling assembly is provided between the first-gear driven gear, the second-gear driven gear, the third-gear driven gear and the shift gear shaft.

7. The integrated electric drive axle with three-speed transmission function according to claim 1, characterized in that, It also includes a power take-off (PTO) assembly, which includes a power engagement sleeve. The PTO assembly engages with the three-speed drive gear through the power engagement sleeve to achieve power take-off.

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