Heavy truck electric drive axle and driving method thereof

Abstract

According to the heavy truck electric drive axle, the two speed reduction assemblies are arranged on the two sides of the speed change mechanism, the motor and the speed reduction assemblies are transversely arranged on the two sides of the speed change mechanism in the axial direction, the transverse space of the electric drive axle is fully utilized, the gravity center suspension height of the electric drive axle is reduced, the size and weight of the electric drive axle are reduced, and the mounting adaptability of the electric drive axle and a heavy truck chassis is improved; the first intermediate shaft and the second intermediate shaft are connected into a whole and connected with the output shaft through gear shifting of the two gear shifting assemblies, or the first intermediate shaft and the second intermediate shaft are connected with the output shaft correspondingly, wheel end driving of three gears is achieved, and power interruption is avoided through successive gear shifting of the two gear shifting assemblies; the two intermediate shafts are coaxial and form a two-stage parallel shaft structure with the output shaft, the number of gears is increased on the premise that the stage number of the parallel shafts is not increased, so that more working condition driving requirements are met, the speed ratio range between the adjacent gears is reduced, the gear shifting smoothness and the transmission efficiency are improved, the suspension height of the drive axle is reduced, and the structural compactness is improved. And the structural stability and reliability are improved.

Description

Technical Field

[0001] The present invention relates to a heavy-duty truck electric drive axle and a driving method thereof, and belongs to the technical field of pure electric variable speed drive. Background Art

[0002] Purely electric heavy-duty commercial trucks typically utilize two drive systems: a central electric drive and an electric axle. Compared to central electric drives, electric axles offer greater space savings and a higher level of integration, leading to wider application. Electric axle assemblies used in medium- and heavy-duty trucks typically utilize a dual-motor drive system. The transmission efficiency and structural design of the electric axle system directly impact vehicle performance. Existing dual-motor electric axle configurations include offset parallel shafts, coaxial full planetary gears, or a combination of parallel shafts and planetary shafts. The electric drive axle system of dual motors + planetary gears, in which one motor serves as the main drive motor and the other serves as the auxiliary drive motor, currently mostly adopts a two-speed transmission arrangement in the industry; the electric drive axle system of dual motors + parallel shafts adopts a two-stage parallel shaft gear transmission; the electric drive axle system of dual motors + parallel shafts + planetary gears uses a two-stage parallel shaft gear transmission and is driven by a first-stage planetary gear to reduce speed and increase torque; these types of electric drive axles all have a small number of gears, and are unable to further narrow the speed ratio difference between gears, making it difficult to achieve smooth gear shifting of the electric drive axle, and it is difficult to take into account the speed of each motor in its optimal efficiency range. In order to reduce the speed ratio difference between gears, improve the coverage of the motor's high-efficiency range and meet the various torque requirements of heavy-duty vehicles, more gears need to be set in the integrated electric drive axle. For example, the two-stage parallel shaft reduction can be improved to a three-stage parallel shaft reduction to achieve a multi-speed ratio layout. However, the multi-speed ratio layout has many transmission stages, which increases the layout space, increases the size of the transmission, and has a large center of gravity suspension. It has high requirements for the installation space of the heavy-duty truck chassis and poor adaptability, and affects the transmission efficiency, making it difficult to ensure the stability and reliability of the structure. Summary of the Invention

[0003] The heavy-duty truck electric drive axle provided by the present invention reduces the center of gravity suspension height of the electric drive axle, improving the installation compatibility of the electric drive axle with the heavy-duty truck chassis. The two shift assemblies shift gears sequentially to avoid power interruption. The two intermediate shafts are coaxial with the output shaft to form a two-stage parallel shaft structure. This increases the number of gears without increasing the number of parallel shaft stages, thereby meeting the driving requirements of more working conditions. This reduces the speed ratio difference between adjacent gears, improves shifting smoothness and transmission efficiency, and reduces the suspension height of the drive axle, improving the compactness, stability, and reliability of the structure. The present invention also provides a driving method for the heavy-duty truck electric drive axle.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: A heavy-duty truck electric drive axle includes a motor 1, a reduction assembly 1 connected to the motor 1, a motor 2, a reduction assembly 2 connected to the motor 2, a speed change mechanism, a differential, and a half-shaft assembled on the differential. The characteristics are: the reduction assembly 1 and the reduction assembly 2 are arranged on both sides of the speed change mechanism, the speed change mechanism includes an intermediate shaft 1 engaged with the output end of the reduction assembly 1, a shift assembly 1 assembled on the intermediate shaft 1, an intermediate shaft 2 engaged with the output end of the reduction assembly 2 and arranged coaxially with the intermediate shaft, the shift assembly 2 assembled on the intermediate shaft 2, and an output shaft engaged with the differential, and the intermediate shaft 1 and the intermediate shaft 2 are connected into a whole and connected to the output shaft as the shift assembly 1 and the shift assembly 2 shift, or are connected to the output shaft separately.

[0005] Preferably, the reduction assembly 1 includes an input shaft 1 connected to the motor 1, a constant meshing shaft 1 meshing with the input shaft 1, and a constant meshing driving gear 1 fixed on the constant meshing shaft 1 and meshing with the intermediate shaft 1; the reduction assembly 2 includes an input shaft 2 connected to the motor 2, a constant meshing shaft 2 meshing with the input shaft 2, and a constant meshing driving gear 2 fixed on the constant meshing shaft 2 and meshing with the intermediate shaft 2.

[0006] Preferably, the intermediate shaft 2 is rotatably sleeved on the intermediate shaft 1, the input shaft 1 and the input shaft 2 are coaxially aligned with the intermediate shaft, the intermediate shaft 1 is fixed with a constant meshing driven gear 1 that meshes with the constant meshing driving gear 1, and the intermediate shaft 2 is fixed with a constant meshing driven gear 2 that meshes with the constant meshing driving gear 2.

[0007] Preferably, the shift assembly includes a shift gear coaxially fixed on the intermediate shaft, a sliding gear sleeve axially slidably mounted on the shift gear, and a gear driving gear rotatably mounted on the intermediate shaft and meshing with the output shaft. The gear driving gear is located on the left side of the sliding gear sleeve, and the sliding gear sleeve slides to the left to combine with the gear driving gear, forming a connection between the intermediate shaft and the output shaft.

[0008] Preferably, the shift assembly 2 includes a shift gear 2 coaxially fixed on the intermediate shaft 2, a sliding gear sleeve 2 axially slidably assembled on the shift gear 2, and a gear driving gear 2 rotatably mounted on the intermediate shaft 2 and meshing with the output shaft. The gear driving gear 2 is located on the right side of the sliding gear sleeve 2, and the sliding gear sleeve 2 slides to the right to combine with the gear gear 2 to form a connection between the intermediate shaft 2 and the output shaft.

[0009] Preferably, the gear driving gear 1, the shift gear 1, the shift gear 2 and the gear driving gear 2 are coaxially aligned from left to right in sequence; the sliding gear sleeve 1 slides to the left and combines with the gear driving gear 1, and the sliding gear sleeve 2 slides to the left and combines with the shift gear 1, connecting the intermediate shaft 1 and the intermediate shaft 2 as a whole and connecting the intermediate shaft 1 to the output shaft; the sliding gear sleeve 2 slides to the right and combines with the gear driving gear 2, and the sliding gear sleeve 1 slides to the right and combines with the shift gear 2, connecting the intermediate shaft 1 and the intermediate shaft 2 as a whole and connecting the intermediate shaft 2 to the output shaft; the sliding gear sleeve 1 slides to the left and combines with the gear driving gear 1, and the sliding gear sleeve 2 slides to the right and combines with the gear driving gear 2, connecting the intermediate shaft 1 and the intermediate shaft 2 to the output shaft respectively.

[0010] Preferably, the output shaft is coaxially fixed with a gear driven gear 1 engaged with the gear driving gear 1, a gear driven gear 2 engaged with the gear driving gear 2, and an output gear engaged with the differential. The output gear is located between the gear driven gear 1 and the gear driven gear 2, and the differential case of the differential has a differential case gear engaged with the output gear.

[0011] Preferably, a wheel-end planetary gear set is mounted on the half shaft.

[0012] In the above-mentioned driving method of the heavy-duty truck electric drive axle, the first shift assembly and the second shift assembly are both in the neutral position in the initial state, which is characterized by: Shift the shift assembly 1 and the shift assembly 2 separately to connect the intermediate shaft 1 and the intermediate shaft 2 into a whole and connect the intermediate shaft 1 to the output shaft, forming a first gear on the output shaft and transmitting the power to the differential. The differential drives the half shaft to move and form a first gear drive to the wheel end; Shifting the shift assembly 1 and the shift assembly 2 respectively connects the intermediate shaft 1 and the intermediate shaft 2 to the output shaft, thereby forming the second gear on the output shaft and transmitting the power to the differential. The differential drives the half shaft to move and forms the second gear drive on the wheel end. Shift the shift assembly 1 and the shift assembly 2 separately to connect the intermediate shaft 1 and the intermediate shaft 2 into a whole and connect the intermediate shaft 2 to the output shaft, forming a third gear on the output shaft and transmitting it to the differential. The differential drives the half-shaft to move to form a third gear drive for the wheel end.

[0013] Preferably, "shifting the shift assembly 1 and the shift assembly 2 respectively so that the intermediate shaft 1 and the intermediate shaft 2 are connected as a whole, and the intermediate shaft 1 is connected to the output shaft" means that the sliding gear sleeve 1 slides to the left and is combined with the gear driving gear 1, and the sliding gear sleeve 2 slides to the left and is combined with the shift gear 1; "shifting the shift assembly 1 and the shift assembly 2 respectively so that the intermediate shaft 1 and the intermediate shaft 2 are connected as a whole, and the intermediate shaft 2 is connected to the output shaft" means that the sliding gear sleeve 2 slides to the right and is combined with the gear driving gear 2, and the sliding gear sleeve 1 slides to the right and is combined with the shift gear 2.

[0014] The beneficial effects of the present invention are: The heavy-duty truck electric drive axle of the present invention has two groups of reduction gear assemblies arranged on both sides of the speed change mechanism, forming a motor and a reduction gear assemblies arranged horizontally along the axial direction on both sides of the speed change mechanism, making full use of the lateral space of the electric drive axle, reducing the center of gravity suspension height of the electric drive axle, so as to reduce the volume and weight of the electric drive axle, and improve the installation adaptability of the electric drive axle and the heavy-duty truck chassis. The output end of the reduction gear assembly one is engaged with the intermediate shaft one, and the power of the motor one is reduced and transmitted to the intermediate shaft one. The output end of the reduction gear assembly two is engaged with the intermediate shaft two, and the power of the motor two is reduced and transmitted to the intermediate shaft two. Through the shifting of the two groups of shift assemblies, the intermediate shaft one and the intermediate shaft two are connected into a whole and connected to the output shaft, or the intermediate shaft one and the intermediate shaft two are connected to the output shaft respectively, and the power on the intermediate shaft one and the intermediate shaft two is transmitted to the output shaft. The output shaft drives the differential to operate, so that the half shafts rotate to transmit the power to The wheel end is driven. When the intermediate shaft one and the intermediate shaft two are connected as a whole and the intermediate shaft one is connected to the output shaft, the first gear power is formed on the output shaft to realize the first gear drive of the wheel end. When the intermediate shaft one and the intermediate shaft two are respectively connected to the output shaft, the second gear power is formed on the output shaft to realize the second gear drive of the wheel end. When the intermediate shaft one and the intermediate shaft two are connected as a whole and the intermediate shaft two is connected to the output shaft, the third gear power is formed on the output shaft to realize the third gear drive of the wheel end. The successive shifting of the two groups of shift components avoids power interruption. The two intermediate shafts are coaxial with the output shaft to form a two-stage parallel shaft structure. The number of gears is increased without increasing the number of parallel shaft stages, so as to take into account the driving requirements of more working conditions, reduce the speed ratio difference between adjacent gears, improve the gear shifting smoothness and transmission efficiency, and reduce the suspension height of the drive axle, improve the structural compactness, and improve the structural stability and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the transmission structure of the heavy-duty truck electric drive axle in a specific implementation manner.

[0016] Figure 2 This is a schematic diagram of the transmission structure of the heavy-duty truck electric drive assembly when driving in first gear.

[0017] Figure 3 This is a schematic diagram of the transmission structure of the heavy-duty truck electric drive assembly in second gear drive.

[0018] Figure 4 This is a schematic diagram of the transmission structure of the heavy-duty truck electric drive assembly in three-speed drive. DETAILED DESCRIPTION

[0019] The following combination Figures 1 to 4 The embodiments of the present invention are described in detail.

[0020] The heavy-duty truck electric drive axle includes a motor 1, a reduction assembly 3 connected to the motor 1, a motor 2, a reduction assembly 4 connected to the motor 22, a speed change mechanism 5, a differential 6 and a half shaft 7 assembled on the differential 6, characterized in that the reduction assembly 3 and the reduction assembly 24 are arranged on both sides of the speed change mechanism 5, the speed change mechanism 5 includes an intermediate shaft 8 engaged with the output end of the reduction assembly 3, a shift assembly 9 assembled on the intermediate shaft 8, an intermediate shaft 2 10 engaged with the output end of the reduction assembly 24 and coaxially arranged with the intermediate shaft 8, a shift assembly 2 11 assembled on the intermediate shaft 2 10 and an output shaft 12 engaged with the differential 6, and the intermediate shaft 8 and the intermediate shaft 2 10 are connected as a whole and connected to the output shaft 12 as the shift assembly 9 and the shift assembly 2 11 shift, or are connected to the output shaft 12 separately.

[0021] The heavy-duty truck electric drive axle described above has two groups of reduction components arranged on both sides of the speed change mechanism 5, forming a motor and reduction components arranged horizontally along the axial direction on both sides of the speed change mechanism 5, making full use of the lateral space of the electric drive axle, reducing the center of gravity suspension height of the electric drive axle, so as to reduce the volume and weight of the electric drive axle, and improve the installation adaptability of the electric drive axle and the heavy-duty truck chassis. The output end of the reduction component 13 is engaged with the intermediate shaft 18, which reduces the power of the motor 1 and transmits it to the intermediate shaft 18. The output end of the reduction component 24 is engaged with the intermediate shaft 210, which reduces the power of the motor 22 and transmits it to the intermediate shaft 210. Through the shifting of the two groups of shift components, the intermediate shaft 18 and the intermediate shaft 210 are connected as a whole and connected to the output shaft 12, or the intermediate shaft 18 and the intermediate shaft 210 are respectively connected to the output shaft 12, and the power on the intermediate shaft 18 and the intermediate shaft 210 is transmitted to the output shaft 12. The output shaft 12 drives the differential 6 to operate, so that the half shaft 7 rotates to drive the dynamic The force is transmitted to the wheel end to achieve driving. When the intermediate shaft 1 8 and the intermediate shaft 2 10 are connected as a whole and the intermediate shaft 1 8 is connected to the output shaft 12, a first gear power is formed on the output shaft 12 to achieve a first gear drive to the wheel end. When the intermediate shaft 1 8 and the intermediate shaft 2 10 are respectively connected to the output shaft 12, a second gear power is formed on the output shaft 12 to achieve a second gear drive to the wheel end. When the intermediate shaft 1 8 and the intermediate shaft 2 10 are connected as a whole and the intermediate shaft 2 10 is connected to the output shaft 12, a third gear power is formed on the output shaft 12 to achieve a third gear drive to the wheel end. The sequential shifting of the two groups of shift assemblies avoids power interruption. The two intermediate shafts are coaxial with the output shaft to form a two-stage parallel shaft structure. The number of gears is increased without increasing the number of parallel shaft stages, so as to take into account the driving requirements of more working conditions, reduce the speed ratio difference between adjacent gears, improve the gear shifting smoothness and transmission efficiency, and reduce the suspension height of the drive axle, improve the structural compactness, and improve the structural stability and reliability.

[0022] The reduction assembly 1 (3) includes an input shaft 1 (31) connected to the motor 1 (1), a constant mesh shaft 1 (32) meshing with the input shaft 1 (31), and a constant mesh driving gear 1 (33) fixed to the constant mesh shaft 1 (32) and meshing with the intermediate shaft 1 (8). The reduction assembly 2 (4) includes an input shaft 2 (41) connected to the motor 2 (2), a constant mesh shaft 2 (42) meshing with the input shaft 2 (41), and a constant mesh driving gear 2 (43) fixed to the constant mesh shaft 2 (42) and meshing with the intermediate shaft 2 (10). The power of the motor 1 (1) is transmitted to the intermediate shaft 1 (8) via the input shaft 1 (31), the constant mesh shaft 1 (32), and the constant mesh driving gear 1 (33), thereby reducing the power of the motor 1 and transmitting it to the intermediate shaft 1 (8). The power of the motor 2 (2) is transmitted to the intermediate shaft 2 (10) via the input shaft 2 (41), the constant mesh shaft 2 (42), and the constant mesh driving gear 2 (43), thereby reducing the power of the motor 2 (2) and transmitting it to the intermediate shaft 2 (10).

[0023] Among them, the intermediate shaft 2 10 is rotatably sleeved on the intermediate shaft 1 8, the input shaft 1 31 and the input shaft 2 41 are coaxially aligned with the intermediate shaft 1 8, and the intermediate shaft 1 8 is fixed with a constantly meshed driven gear 1 81 that meshes with the constantly meshed driving gear 1 33, and the intermediate shaft 2 10 is fixed with a constantly meshed driven gear 2 101 that meshes with the constantly meshed driving gear 2 43. Intermediate shaft 2 10 is sleeved on intermediate shaft 1 8 , which can effectively shorten the axial length of the speed change mechanism. Intermediate shaft 1 8 provides support for intermediate shaft 2 10 , improving structural compactness and reliability. Input shaft 1 31 and input shaft 2 41 are coaxially aligned with the intermediate shaft, forming a coaxial arrangement of two reduction assemblies and the speed change mechanism 5 , fully utilizing the axial space of the drive axle and reducing the suspension height of the drive axle. The power on constant mesh shaft 1 32 is transmitted to intermediate shaft 1 8 through the engagement of constant mesh driving gear 1 33 with constant mesh driven gear 1 81 , and the power on constant mesh shaft 2 42 is transmitted to intermediate shaft 2 10 through the engagement of constant mesh driving gear 2 43 with constant mesh driven gear 2 101 .

[0024] Among them, the shift assembly 9 includes a shift gear 91 coaxially fixed on the intermediate shaft 8, a sliding gear sleeve 92 axially slidably assembled on the shift gear 91, and a gear driving gear 93 rotatably mounted on the intermediate shaft 8 and engaged with the output shaft. The gear driving gear 93 is located on the left side of the sliding gear sleeve 93. The sliding gear sleeve 92 slides to the left and combines with the gear driving gear 91 to form a connection between the intermediate shaft 8 and the output shaft 12. The shift gear 91 and the sliding gear sleeve 92 rotate synchronously with the intermediate shaft 8. When the sliding gear sleeve 92 is not engaged with the gear driving gear 93, the gear driving gear 93 will not rotate synchronously with the intermediate shaft 8, and the intermediate shaft 8 cannot drive the output shaft 12 to rotate. The intermediate shaft 8 and the output shaft 12 are not connected. When the sliding gear sleeve 92 slides to the left and engages with the gear driving gear 93, the sliding gear sleeve 92 drives the gear driving gear 93 to rotate synchronously, and the gear driving gear 93 drives the output shaft to rotate, forming a connection between the intermediate shaft 8 and the output shaft 12.

[0025] Among them, the shift assembly 2 11 includes a shift gear 2 111 coaxially fixed on the intermediate shaft 2 10, a sliding gear sleeve 2 112 axially slidably assembled on the shift gear 2 111, and a gear driving gear 2 113 rotatably mounted on the intermediate shaft 2 10 and meshing with the output shaft 12. The gear driving gear 2 113 is located on the right side of the sliding gear sleeve 2 112. The sliding gear sleeve 2 112 slides to the right and combines with the gear gear 2 113 to form a connection between the intermediate shaft 2 10 and the output shaft 12. The second shift gear 111 and the second sliding gear sleeve 112 rotate synchronously with the second intermediate shaft 10. When the second sliding gear sleeve 112 is not engaged with the second gear driving gear 113, the second gear driving gear 113 does not rotate synchronously with the second intermediate shaft 10, and the second intermediate shaft 10 cannot drive the output shaft 12 to rotate. The second intermediate shaft 10 and the output shaft 12 are not connected. When the second sliding gear sleeve 112 slides rightward and engages with the second gear driving gear 113, the second sliding gear sleeve 112 drives the second gear driving gear 113 to rotate synchronously, and the second gear driving gear 113 drives the output shaft 12 to rotate, forming a connection between the second intermediate shaft 10 and the output shaft 12. The two shift assemblies have the same structure, and the gear sizes of the two shift assemblies only need to be set according to the required gear ratio. The structure is simple, and shifting only requires operating the two sliding gear sleeves, which is convenient.

[0026] Among them, the gear driving gear 1 93, the shift gear 1 91, the shift gear 2 111 and the gear driving gear 2 113 are coaxially aligned from left to right; the sliding gear sleeve 1 92 slides to the left and combines with the gear driving gear 1 93 and the sliding gear sleeve 2 112 slides to the left and combines with the shift gear 1 91, connecting the intermediate shaft 1 8 and the intermediate shaft 2 10 into a whole and connecting the intermediate shaft 1 8 to the output shaft 12. At this time, a first gear power will be formed on the output shaft 12; the sliding gear sleeve 2 112 slides to the right and combines with the gear driving gear 2 113 and the sliding gear sleeve 2 Sleeve 1 92 slides to the right and engages with shift gear 2 111, connecting intermediate shaft 1 8 and intermediate shaft 2 10 into a whole and connecting intermediate shaft 2 10 to output shaft 12. At this time, third gear power is generated on output shaft 12; sliding gear sleeve 1 92 slides to the left and engages with gear driving gear 1 93, and sliding gear sleeve 2 112 slides to the right and engages with gear driving gear 2 113, connecting intermediate shaft 1 8 and intermediate shaft 2 10 to output shaft 12 respectively. At this time, intermediate shaft 1 8 and intermediate shaft 2 10 are not connected together, and second gear power is generated on output shaft 12. The gear driving gear 1 93, the shift gear 1 91, the shift gear 2 111 and the gear driving gear 2 11 are arranged in sequence along the axial direction, and the gear shifting is achieved by switching the sliding directions of the sliding gear sleeve 1 92 and the sliding gear sleeve 2 112. The sliding gear sleeve 1 92 and the sliding gear sleeve 112 are coaxially arranged in sequence, which reduces the gear setting space, simplifies the structure of the speed change mechanism and the shift execution structure coordinated with the speed change mechanism, and improves the shifting efficiency.

[0027] Coaxially fixed to the output shaft 12 are a shift driven gear 121 meshing with the shift driving gear 1 93, a shift driven gear 2 122 meshing with the shift driving gear 2 113, and an output gear 123 meshing with the differential 6. Output gear 123 is located between shift driven gear 121 and shift driven gear 2 122. The differential case of the differential 6 has differential case teeth 61 meshing with the output gear 123. When the sliding gear sleeve 1 92 engages with the shift driving gear 1 93, power from the intermediate shaft 1 8 is transmitted to the output shaft 12 via the shift driving gear 1 93 and the shift driven gear 1 121. This drives the differential case, causing the differential 6 to operate. When the sliding gear sleeve 112 engages with the shift driving gear 2 113, power from the intermediate shaft 2 10 is transmitted to the output shaft 12 via the shift driving gear 2 113 and the shift driven gear 2 122. This drives the differential case, causing the differential 6 to operate.

[0028] The wheel-end planetary gear 71 is mounted on the half shaft 7. The deceleration of the wheel-end planetary gear 71 further increases the wheel-end torque, meeting the high-torque drive requirements of heavy trucks.

[0029] In the above-mentioned driving method of the heavy-duty truck electric drive axle, the shift assembly 1 9 and the shift assembly 2 11 are both in the neutral position in the initial state, which is characterized by: Shift the shift assembly 1 9 and the shift assembly 2 11 separately to connect the intermediate shaft 1 8 and the intermediate shaft 2 10 into a whole and connect the intermediate shaft 1 8 to the output shaft 12. The output shaft 12 forms a first gear power transmission to the differential 6. The differential 6 drives the half shaft 7 to move and form a first gear drive to the wheel end. Shifting the shift assembly 1 9 and the shift assembly 2 11 respectively connects the intermediate shaft 1 8 and the intermediate shaft 2 10 to the output shaft 12, forming the second gear on the output shaft 12 and transmitting the power to the differential 6. The differential 6 drives the half shaft 7 to move and form the second gear drive for the wheel end. Shifting assembly 1 9 and shifting assembly 2 11 respectively connects intermediate shaft 1 8 and intermediate shaft 2 10 into a whole and connects intermediate shaft 2 10 to output shaft 12. Third gear power is formed on output shaft 12 and transmitted to differential 6. Differential 6 drives half shaft 7 to move to form third gear drive for wheel end.

[0030] In the driving method described above, the two groups of shift components shift in sequence to avoid power interruption, take into account the driving requirements of more working conditions, reduce the speed ratio difference between adjacent gears, and improve shifting smoothness and transmission efficiency.

[0031] Among them, "shifting the shift assembly 1 9 and the shift assembly 2 11 respectively so that the intermediate shaft 1 8 and the intermediate shaft 2 10 are connected as a whole, and the intermediate shaft 1 8 is connected to the output shaft 12" means that the sliding gear sleeve 1 92 slides to the left to be combined with the gear driving gear 1 93 and the sliding gear sleeve 2 112 slides to the left to be combined with the shift gear 1 91; "shifting the shift assembly 1 9 and the shift assembly 2 11 respectively so that the intermediate shaft 1 8 and the intermediate shaft 2 10 are connected as a whole, and the intermediate shaft 2 10 is connected to the output shaft 12" means that the sliding gear sleeve 2 112 slides to the right to be combined with the gear driving gear 2 113 and the sliding gear sleeve 1 92 slides to the right to be combined with the shift gear 2 111.

[0032] like Figure 2 As shown, when first gear drive is established, sliding gear sleeve 1 92 slides leftward and engages with gear driving gear 1 93, sliding gear sleeve 2 112 slides leftward and engages with shift gear 1 91, intermediate shaft 1 8 and intermediate shaft 2 10 are connected as a whole, and intermediate shaft 1 8 is connected to output shaft 12. The power of motor 1 is transmitted to intermediate shaft 1 8 via reduction assembly 1 3, and the power of motor 2 is transmitted to intermediate shaft 2 10 via reduction assembly 2 4. The power is combined on intermediate shaft 1 8 and transmitted from intermediate shaft 8 to output shaft 12. The first gear power is generated on output shaft 12 and transmitted to differential 6. Differential 6 drives half shafts 7 to move, generating first gear drive for the wheel ends. The wheel ends driven in first gear have the maximum torque and the minimum speed, which is suitable for full-load and high-torque conditions.

[0033] like Figure 3As shown, when second gear drive is established, sliding gear sleeve 1 92 slides leftward and engages with gear driving gear 1 93, and sliding gear sleeve 2 112 slides rightward and engages with gear driving gear 2 113, connecting intermediate shaft 1 8 and intermediate shaft 2 10 to output shaft 12 respectively. The power of motor 1 1 is transmitted to output shaft 12 via reduction assembly 1 3 and intermediate shaft 1 8. The power of motor 2 is transmitted to output shaft 12 via reduction assembly 2 4 and intermediate shaft 2 10. The power is combined on output shaft 12 to form second gear power, which is transmitted to differential 6. Differential 6 drives half shaft 7 to move, generating second gear drive for the wheel ends. The wheel end torque of second gear drive is less than that of first gear drive, and the speed is greater than that of first gear drive, making it suitable for full-load acceleration conditions.

[0034] like Figure 4 As shown, when third-gear drive is established, sliding gear sleeve 2 112 slides rightward and engages with gear driving gear 2 113, sliding gear sleeve 1 92 slides rightward and engages with shift gear 2 111, intermediate shaft 1 8 and intermediate shaft 2 10 are connected as a whole, and intermediate shaft 2 10 is connected to output shaft 12. The power of motor 1 1 is transmitted to intermediate shaft 1 8 via reduction assembly 1 3, and the power of motor 2 2 is transmitted to intermediate shaft 2 10 via reduction assembly 2 4. The power is combined on intermediate shaft 2 10 and transmitted from intermediate shaft 2 10 to output shaft 12. Third-gear power is generated on output shaft 12 and transmitted to differential 6. Differential 6 drives half shafts 7 to move, generating third-gear drive for the wheel ends. The wheel-end torque of third-gear drive is less than that of second-gear drive, and the speed is greater than that of second-gear drive, making it suitable for light-load and high-speed operating conditions.

[0035] During the gear shifting process, the sliding gear sleeve 1 92 and the sliding gear sleeve 2 112 slide successively to avoid power interruption caused by synchronous gear shifting. The switching between the first gear power and the third gear power needs to go through the second gear power, which reduces the gear shifting shock and improves the gear shifting smoothness.

[0036] The above fully describes the technical solutions of the embodiments of the present invention in conjunction with the accompanying drawings. It should be noted that the embodiments described are only part of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

Claims

1. A heavy-duty truck electric drive axle, comprising a first motor, a first reduction assembly connected to the first motor, a second motor, a second reduction assembly connected to the second motor, a speed change mechanism, a differential, and a half-shaft assembled on the differential, characterized in that: The reduction assembly 1 and the reduction assembly 2 are arranged on both sides of the speed change mechanism. The speed change mechanism includes an intermediate shaft 1 engaged with the output end of the reduction assembly 1, a shift assembly 1 assembled on the intermediate shaft 1, an intermediate shaft 2 engaged with the output end of the reduction assembly 2 and arranged coaxially with the intermediate shaft, a shift assembly 2 assembled on the intermediate shaft 2, and an output shaft engaged with the differential. The intermediate shaft 1 and the intermediate shaft 2 are connected as a whole and connected to the output shaft as the shift assembly 1 and the shift assembly 2 shift, or are connected to the output shaft separately.

2. The heavy truck electric drive axle according to claim 1, characterized in that: The reduction assembly 1 includes an input shaft 1 connected to the motor 1, a constant meshing shaft 1 meshing with the input shaft 1, and a constant meshing driving gear 1 fixed on the constant meshing shaft 1 and meshing with the intermediate shaft 1. The reduction assembly 2 includes an input shaft 2 connected to the motor 2, a constant meshing shaft 2 meshing with the input shaft 2, and a constant meshing driving gear 2 fixed on the constant meshing shaft 2 and meshing with the intermediate shaft 2.

3. The heavy truck electric drive axle according to claim 2, characterized in that: The intermediate shaft 2 is rotatably sleeved on the intermediate shaft 1, the input shaft 1 and the input shaft 2 are coaxially aligned with the intermediate shaft, the intermediate shaft 1 is fixed with a constant meshing driven gear 1 meshing with the constant meshing driving gear 1, and the intermediate shaft 2 is fixed with a constant meshing driven gear 2 meshing with the constant meshing driving gear 2.

4. The heavy truck electric drive axle according to claim 3, characterized in that: The shift assembly includes a shift gear coaxially fixed to an intermediate shaft, a sliding gear sleeve axially slidably mounted on the shift gear, and a gear driving gear rotatably mounted on the intermediate shaft and meshing with the output shaft. The gear driving gear is located on the left side of the sliding gear sleeve. The sliding gear sleeve slides to the left and engages with the gear driving gear, forming a connection between the intermediate shaft and the output shaft.

5. The heavy truck electric drive axle according to claim 4, characterized in that: The shift assembly 2 includes a shift gear 2 coaxially fixed on the intermediate shaft 2, a sliding gear sleeve 2 axially slidably assembled on the shift gear 2, and a gear driving gear 2 rotatably mounted on the intermediate shaft 2 and meshing with the output shaft. The gear driving gear 2 is located on the right side of the sliding gear sleeve 2. The sliding gear sleeve 2 slides to the right and combines with the gear gear 2 to form a connection between the intermediate shaft 2 and the output shaft.

6. The heavy truck electric drive axle according to claim 5, characterized in that: The gear driving gear 1, the shift gear 1, the shift gear 2 and the gear driving gear 2 are coaxially aligned from left to right in sequence; the sliding gear sleeve 1 slides to the left and combines with the gear driving gear 1, and the sliding gear sleeve 2 slides to the left and combines with the shift gear 1, connecting the intermediate shaft 1 and the intermediate shaft 2 as a whole and connecting the intermediate shaft 1 to the output shaft; the sliding gear sleeve 2 slides to the right and combines with the gear driving gear 2, and the sliding gear sleeve 1 slides to the right and combines with the shift gear 2, connecting the intermediate shaft 1 and the intermediate shaft 2 as a whole and connecting the intermediate shaft 2 to the output shaft; the sliding gear sleeve 1 slides to the left and combines with the gear driving gear 1, and the sliding gear sleeve 2 slides to the right and combines with the gear driving gear 2, connecting the intermediate shaft 1 and the intermediate shaft 2 to the output shaft respectively.

7. The heavy truck electric drive axle according to claim 5, characterized in that: The output shaft is coaxially fixed with a gear driven gear 1 meshing with the gear driving gear 1, a gear driven gear 2 meshing with the gear driving gear 2, and an output gear meshing with the differential. The output gear is located between the gear driven gear 1 and the gear driven gear 2, and the differential case of the differential has a differential case gear meshing with the output gear.

8. The heavy truck electric drive axle according to claim 1, characterized in that: The wheel end planetary gear is assembled on the half shaft.

9. The driving method of a heavy truck electric drive axle according to any one of claims 1 to 8, wherein the first shift assembly and the second shift assembly are both in the neutral position in an initial state, characterized in that: Shift the shift assembly 1 and the shift assembly 2 separately to connect the intermediate shaft 1 and the intermediate shaft 2 into a whole and connect the intermediate shaft 1 to the output shaft, forming a first gear on the output shaft and transmitting the power to the differential. The differential drives the half shaft to move and form a first gear drive to the wheel end; Shifting the shift assembly 1 and the shift assembly 2 respectively connects the intermediate shaft 1 and the intermediate shaft 2 to the output shaft, thereby forming the second gear on the output shaft and transmitting the power to the differential. The differential drives the half shaft to move and forms the second gear drive on the wheel end. Shift the shift assembly 1 and the shift assembly 2 separately to connect the intermediate shaft 1 and the intermediate shaft 2 into a whole and connect the intermediate shaft 2 to the output shaft, forming a third gear on the output shaft and transmitting it to the differential. The differential drives the half-shaft to move to form a third gear drive for the wheel end.

10. The driving method of a heavy truck electric drive axle according to claim 9, characterized in that: "Shifting the shift assembly 1 and the shift assembly 2 respectively so that the intermediate shaft 1 and the intermediate shaft 2 are connected as a whole, and the intermediate shaft 1 is connected to the output shaft" means that the sliding gear sleeve 1 slides to the left and is combined with the gear driving gear 1, and the sliding gear sleeve 2 slides to the left and is combined with the shift gear 1; "Shifting the shift assembly 1 and the shift assembly 2 respectively so that the intermediate shaft 1 and the intermediate shaft 2 are connected as a whole, and the intermediate shaft 2 is connected to the output shaft" means that the sliding gear sleeve 2 slides to the right and is combined with the gear driving gear 2, and the sliding gear sleeve 1 slides to the right and is combined with the shift gear 2.

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