Dual-motor four-speed electric drive transmission system and vehicle

Abstract

The present invention relates to the field of transmission technology, and particularly to a dual-motor four-speed electric drive transmission system and a vehicle. The dual-motor four-speed electric drive transmission system provided by the present invention includes: a first motor, a second motor, a first power output shaft, a second power output shaft, a first intermediate rotating shaft, a second intermediate rotating shaft, an output shaft, a first intermediate shaft gear mechanism, a second intermediate shaft gear mechanism, a first shifting mechanism, a second shifting mechanism, a third shifting mechanism, and a fourth shifting mechanism. The dual-motor four-speed electric drive transmission system provided by the present invention can achieve a variety of different operating conditions of two sets of motor power sources. Four power transmission paths are constructed in the power transmission system. During the shifting process, by controlling four shifting devices, the switching between the four power transmission paths is realized, so as to ensure that the power is not interrupted during shifting, reduce the shifting jerks during driving, make the power switching smoother, and the comfort and safety of the vehicle are better.

Description

Technical Field

[0001] The present invention relates to the technical field of electric drive transmission systems, and in particular to a dual-motor four-speed electric drive transmission system and a vehicle. Background Art

[0002] The electric drive transmission system is a transmission system used in electric vehicles. The electric drive transmission system includes a motor and a gear transmission system. The motor outputs power from the output shaft through the gear transmission system. In the prior art, the electric drive transmission used in heavy vehicles is usually driven by a single motor, and the single motor is coaxially arranged with the output shaft.

[0003] In the electric drive transmission system in the prior art, the drive motor must be unloaded during the gear shifting process, and there is a power interruption during the gear shifting, which will seriously affect the driving comfort and safety of the vehicle.

[0004] Therefore, how to solve the problem of power interruption during gear shifting in the electric drive transmission system in the prior art has become an important technical problem to be solved by those skilled in the art. Summary of the invention

[0005] The present invention provides a dual-motor four-speed electric drive transmission system and a vehicle, which can solve the problem of power interruption during gear shifting.

[0006] A first aspect of the present invention provides a dual-motor four-speed electric drive transmission system, comprising:

[0007] First motor;

[0008] Second motor;

[0009] A first power output shaft is transmission-connected to the power output end of the first motor, a first gear is sleeved on the first power output shaft, and a second gear is fixedly sleeved on the first power output shaft;

[0010] A second power output shaft is drivingly connected to the power output end of the second motor, a third gear is fixedly sleeved on the second power output shaft, and an eighth gear is loosely sleeved on the second power output shaft;

[0011] A first rotating shaft, on which a fourth gear and a fifth gear are fixedly sleeved, wherein the fourth gear is respectively in transmission connection with the first gear and the third gear;

[0012] The second rotating shaft is set as a hollow shaft structure, the second rotating shaft is hollowly sleeved on the outer periphery of the first rotating shaft, and the sixth gear and the seventh gear are fixedly sleeved on the second rotating shaft, wherein the sixth gear is respectively connected to the second gear and the eighth gear in transmission;

[0013] The output shaft is sleeved with a ninth gear, a tenth gear, and an eleventh gear loosely.

[0014] The first intermediate shaft gear mechanism includes a first intermediate shaft and a twelfth gear, a thirteenth gear, and a fourteenth gear fixedly sleeved on the first intermediate shaft. Among them, the twelfth gear is in transmission connection with the seventh gear, the thirteenth gear is in transmission connection with the tenth gear, and the fourteenth gear is in transmission connection with the eleventh gear.

[0015] The second intermediate shaft gear mechanism includes a second intermediate shaft and a fifteenth gear and a sixteenth gear fixedly sleeved on the second intermediate shaft. Among them, the fifteenth gear is in transmission connection with the fifth gear, and the sixteenth gear is in transmission connection with the ninth gear.

[0016] The first shifting mechanism can be switched between a first position and a second position. In the first position, the first power output shaft is coupled to the first gear. In the second position, the first power output shaft is disengaged from the first gear.

[0017] The second shifting mechanism can be switched between a third position and a fourth position. In the third position, the second power output shaft is coupled to the eighth gear. In the fourth position, the second power output shaft is disengaged from the eighth gear.

[0018] The third shifting mechanism can be switched between a fifth position, a sixth position, and a seventh position. In the fifth position, the first intermediate rotating shaft is coupled to the output shaft. In the sixth position, the output shaft is coupled to the ninth gear. In the seventh position, the output shaft, the first intermediate rotating shaft, and the ninth gear are disengaged from each other.

[0019] The fourth shifting mechanism can be switched between an eighth position, a ninth position, and a tenth position. In the eighth position, the output shaft is coupled to the tenth gear. In the ninth position, the output shaft is coupled to the eleventh gear. In the tenth position, the output shaft, the tenth gear, and the eleventh gear are disengaged from each other.

[0020] In the dual-motor four-speed electric drive transmission system provided by the present invention, the first intermediate shaft gear mechanism is provided with at least two, and is evenly distributed circumferentially with the output shaft as the axis.

[0021] In the dual-motor four-speed electric drive transmission system provided by the present invention, the second intermediate shaft gear mechanism is provided with at least two, and is evenly distributed circumferentially with the output shaft as the axis.

[0022] In the dual-motor four-speed electric drive transmission system provided by the present invention, the first intermediate rotating shaft and the output shaft are coaxially arranged.

[0023] According to the dual-motor four-speed electric drive transmission system provided by the present invention, the first motor and the second motor are respectively offset on both sides of the first intermediate rotating shaft.

[0024] According to the dual-motor four-speed electric drive transmission system provided by the present invention, with the axis line of the first intermediate rotating shaft as the symmetric center line, the first motor and the second motor are symmetrically arranged.

[0025] According to the dual-motor four-speed electric drive transmission system provided by the present invention, the second intermediate rotating shaft is arranged between the fourth gear and the fifth gear.

[0026] According to the dual-motor four-speed electric drive transmission system provided by the present invention, along the circumferential direction of the output shaft, the gears on the first intermediate shaft gear mechanism and the gears on the second intermediate shaft gear mechanism are staggered.

[0027] According to the dual-motor four-speed electric drive transmission system provided by the present invention, along the axial direction of the output shaft, the second intermediate shaft gear mechanism is arranged between the twelfth gear and the thirteenth gear.

[0028] The second aspect of the present invention provides a vehicle, including the dual-motor four-speed electric drive transmission system described in any one of the above.

[0029] The dual-motor four-speed electric drive transmission system provided by the present invention can realize various different working conditions of two sets of motor power sources. Four power transmission paths are constructed in the power transmission system. During the gear shifting process, by controlling four shifting devices, the switching between the four power transmission paths is realized, so as to ensure that the power is not interrupted during gear shifting, reduce the gear shifting jerks during driving, make the power switching smoother, and the comfort and safety of the vehicle are better.

[0030] For example, when the transmission system operates in the first gear, the first shifting mechanism is in the second position, the second shifting mechanism is in the third position, the third shifting mechanism is in the seventh position, and the fourth shifting mechanism is in the ninth position. The transmission route is as follows:

[0031] The first motor sequentially transmits power to the sixth gear through the first power output shaft → the second gear. At the same time, the second motor sequentially transmits power to the sixth gear through the second power output shaft → the eighth gear. After that, the power of the two motors simultaneously passes through the sixth gear → the second intermediate rotating shaft → the seventh gear → the twelfth gear → the first intermediate shaft → the fourteenth gear → the eleventh gear → the output shaft, and the power is output through the output shaft.

[0032] When switching from the first gear to the second gear, first switch the second shifting mechanism to the fourth position, disengaging the second motor from the output shaft. At this time, the first motor outputs to the output shaft through the original power output route (first-gear power output route), maintaining uninterrupted power. Then, the third shifting mechanism can be switched to the sixth position, and the power of the second motor then passes through the second power output shaft → the third gear → the fourth gear → the first intermediate shaft → the fifth gear → the fifteenth gear → the second intermediate shaft → the sixteenth gear → the ninth gear → the output shaft in sequence. Thus, the second motor completes the upshift operation, and during the upshift process, the power output route of the first motor always remains at the first-gear output route, and the power is not interrupted. After completing the gearshift, the fourth shifting mechanism can first be switched to the tenth position, disengaging the first motor from the output shaft, and then the first shifting mechanism can be switched to the first position. In this way, the power of the first motor and the second motor is simultaneously output through the second-gear output route, ensuring sufficient torque output. Of course, if the torque requirement is small, the first motor can also remain disengaged from the output shaft and stop running, and only the second motor maintains the second-gear output, effectively improving the driving efficiency.

[0033] When switching from the second gear to the third gear, first switch the first shifting mechanism to the second position. At this time, the first motor is disengaged from the output shaft, and the second motor maintains the second-gear output through the original power transmission route, keeping the power uninterrupted. Then, switch the fourth shifting mechanism to the eighth position, and the power of the first motor then passes through the first power output shaft → the second gear → the sixth gear → the second intermediate shaft → the seventh gear → the twelfth gear → the first intermediate shaft → the thirteenth gear → the tenth gear → the output shaft in sequence. In this way, the first motor completes the upshift operation, and during the upshift process, the power output route of the second motor always remains at the second-gear output route, and the power is not interrupted. After completing the gearshift, the third shifting mechanism can first be switched to the seventh position, disengaging the second motor from the output shaft, and then the second shifting mechanism can be switched to the third position. In this way, the power of the first motor and the second motor can be simultaneously output through the third-gear output route, ensuring sufficient torque output. Of course, if the torque requirement is small, the second motor can also remain disengaged from the output shaft and stop running, and only the first motor maintains the third-gear output, effectively improving the driving efficiency.

[0034] When shifting from the third gear to the fourth gear, the second shifting mechanism can be first switched to the fourth position. At this time, the second motor is disengaged from the output shaft, and the first motor maintains the third-gear output through the original power transmission route, keeping the power uninterrupted. Then, the third shifting mechanism can be switched to the fifth position, and the power of the second motor sequentially passes through the second power output shaft → the third gear → the fourth gear → the first intermediate rotating shaft → the output shaft. In this way, the second motor completes the upshifting operation. During the upshifting process, the power output route of the first motor always maintains the third-gear output route, and the power is not interrupted. After completing the gearshift, the fourth shifting mechanism can be first switched to the tenth position, and the first motor is disengaged from the output shaft. Then, the first shifting mechanism can be switched to the first position. In this way, the power of the first motor and the second motor can be output simultaneously through the fourth-gear output route, ensuring sufficient torque output. Of course, if the torque requirement is small, the first motor can also remain disengaged from the output shaft and stop running, and only the second motor maintains the fourth-gear output, effectively improving the driving efficiency.

[0035] Obviously, the technical solution provided by the present invention avoids the situation of power interruption during gear shifting, effectively improving the shifting comfort and safety. At the same time, the dual-motor four-speed electric drive transmission system provided by the present invention can select single-motor operation or dual-motor operation according to the torque requirement, and can effectively improve the driving efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0037] Figure 1 It is a schematic diagram of a dual-motor four-speed electric drive transmission system in the first embodiment of the present invention;

[0038] Figure 2 It is a schematic diagram of a dual-motor four-speed electric drive transmission system in the second embodiment of the present invention.

[0039] Reference Numerals:

[0040] MG1, first motor; MG2, second motor; 10, first power output shaft; 11, second gear; 12, first gear; 20, second power output shaft; 21, third gear; 22, eighth gear; 30, second intermediate shaft; 31, sixth gear; 32, seventh gear; 40, first intermediate shaft; 41, fourth gear; 42, fifth gear; 50, first intermediate shaft; 51, twelfth gear; 52, thirteenth gear; 53, fourteenth gear; 60, second intermediate shaft; 61, fifteenth gear; 62, sixteenth gear; 70, output shaft; 71, ninth gear; 72, tenth gear; 73, eleventh gear; K1, first shift mechanism; K2, second shift mechanism; K3, third shift mechanism; K4, fourth shift mechanism. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] In the prior art, when the electric drive transmission is shifting, the power of the drive motor needs to be cut off first, and then the output shaft of the drive motor is connected to the gear train of the transmission after the shift mechanism completes the shifting action. In this way, there is a power interruption during the shifting, which will seriously affect the driving comfort and safety of the vehicle.

[0043] In view of this, this embodiment provides a dual-motor four-speed electric drive transmission system, please refer to Figure 1 and Figure 2 , including: a first motor MG1, a second motor MG2, a first power output shaft 10, a second power output shaft 20, a first intermediate shaft 40, a second intermediate shaft 30, an output shaft 70, a first intermediate shaft gear mechanism, a second intermediate shaft gear mechanism, a first shift mechanism K1, a second shift mechanism K2, a third shift mechanism K3 and a fourth shift mechanism K4.

[0044] The first power output shaft 10 is connected to the power output end of the first motor MG1 by transmission. Specifically, the first power output shaft 10 and the power output end of the first motor MG1 can be directly connected, or can be connected by transmission mechanisms such as gear transmission. The first power output shaft 10 is sleeved with a first gear 12. Specifically, the first gear 12 can be sleeved on the first power output shaft 10 by a bearing. In addition, the first power output shaft 10 is fixedly sleeved with a second gear 11. Specifically, the second gear 11 can be connected to the first power output shaft 10 by a key.

[0045] The second power output shaft 20 is in transmission connection with the power output end of the second motor MG2. A third gear 21 is fixedly sleeved on the second power output shaft 20, and an eighth gear 22 is sleeved loosely on the second power output shaft 20.

[0046] A fourth gear 41 and a fifth gear 42 are fixedly sleeved on the first intermediate shaft 40. Among them, the fourth gear 41 is in transmission connection with the first gear 12 and the third gear 21 respectively.

[0047] The second intermediate shaft 30 is arranged in a hollow shaft structure. The second intermediate shaft 30 is sleeved loosely on the outer periphery of the first intermediate shaft 40. Specifically, the second intermediate shaft 30 has a central hole axially penetrating inside. The first intermediate shaft 40 passes through the central hole, and a bearing device is arranged between the two. A sixth gear 31 and a seventh gear 32 are fixedly sleeved on the second intermediate shaft 30. Among them, the sixth gear 31 is in transmission connection with the second gear 11 and the eighth gear 22 respectively.

[0048] A ninth gear 71, a tenth gear 72 and an eleventh gear 73 are sleeved loosely on the output shaft 70. It should be noted that the output shaft 70 is used to output power to the wheels to drive the vehicle to move forward.

[0049] The first intermediate shaft gear mechanism includes a first intermediate shaft 50 and a twelfth gear 51, a thirteenth gear 52 and a fourteenth gear 53 fixedly sleeved on the first intermediate shaft 50. Among them, the twelfth gear 51 is in transmission connection with the seventh gear 32, the thirteenth gear 52 is in transmission connection with the tenth gear 72, and the fourteenth gear 53 is in transmission connection with the eleventh gear 73.

[0050] The second intermediate shaft gear mechanism includes a second intermediate shaft 60 and a fifteenth gear 61 and a sixteenth gear 62 fixedly sleeved on the second intermediate shaft 60. Among them, the fifteenth gear 61 is in transmission connection with the fifth gear 42, and the sixteenth gear 62 is in transmission connection with the ninth gear 71.

[0051] The first shifting mechanism K1 can be switched between a first position and a second position. In the first position, the first power output shaft 10 is coupled to the first gear 12. In the second position, the first power output shaft 10 is disengaged from the first gear 12.

[0052] The second shifting mechanism K2 can be switched between a third position and a fourth position. In the third position, the second power output shaft 20 is coupled to the eighth gear 22. In the fourth position, the second power output shaft 20 is disengaged from the eighth gear 22;

[0053] The third shifting mechanism K3 can be switched between a fifth position, a sixth position, and a seventh position. In the fifth position, the first intermediate rotating shaft 40 is coupled to the output shaft 70. In the sixth position, the output shaft 70 is coupled to the ninth gear 71. In the seventh position, the output shaft 70, the first intermediate rotating shaft 40, and the ninth gear 71 are disengaged from each other.

[0054] The fourth shifting mechanism K4 can be switched between an eighth position, a ninth position, and a tenth position. In the eighth position, the output shaft 70 is coupled to the tenth gear 72. In the ninth position, the output shaft 70 is coupled to the eleventh gear 73. In the tenth position, the output shaft 70, the tenth gear 72, and the eleventh gear 73 are disengaged from each other.

[0055] The dual-motor four-speed electric drive transmission system provided in this embodiment can achieve multiple different working conditions of two sets of motor power sources. Four power transmission paths are constructed in the power transmission system. During the shifting process, by controlling the four shifting devices, the switching between the four power transmission paths is realized, so as to ensure that the power is not interrupted during shifting, reduce the shifting jerks during driving, make the power switching smoother, and the comfort and safety of the vehicle are better.

[0056] For example, when the transmission system is running in the first gear, the first shifting mechanism K1 is in the second position, the second shifting mechanism K2 is in the third position, the third shifting mechanism K3 is in the seventh position, and the fourth shifting mechanism K4 is in the ninth position. The transmission route is as follows:

[0057] The first motor MG1 sequentially transmits power to the sixth gear 31 through the first power output shaft 10 → the second gear 11. At the same time, the second motor MG2 sequentially transmits power to the sixth gear 31 through the second power output shaft 20 → the eighth gear 22. After that, the power of the two motors sequentially passes through the sixth gear 31 → the second intermediate rotating shaft 30 → the seventh gear 32 → the twelfth gear 51 → the first intermediate shaft 50 → the fourteenth gear 53 → the eleventh gear 73 → the output shaft 70, and the power is output through the output shaft 70.

[0058] When shifting from the first gear to the second gear, first switch the second shifting mechanism K2 to the fourth position, disengaging the second motor MG2 from the output shaft 70. At this time, the first motor MG1 outputs power to the output shaft 70 through the original power output route (first-gear power output route), maintaining uninterrupted power. Then, the third shifting mechanism K3 can be switched to the sixth position, and the power of the second motor MG2 sequentially passes through the second power output shaft 20 → third gear 21 → fourth gear 41 → first intermediate rotating shaft 40 → fifth gear 42 → fifteenth gear 61 → second intermediate shaft 60 → sixteenth gear 62 → ninth gear 71 → output shaft 70. The second motor MG2 completes the upshift operation. During the upshift process, the power output route of the first motor MG1 always remains in the first-gear output route, and the power is not interrupted. After completing the gear shift, the fourth shifting mechanism K4 can first be switched to the tenth position, disengaging the first motor MG1 from the output shaft 70. Then, the first shifting mechanism K1 can be switched to the first position. In this way, the power of the first motor MG1 and the second motor MG2 is simultaneously output through the second-gear output route, ensuring sufficient torque output. Of course, if the torque requirement is small, the first motor MG1 can also remain disengaged from the output shaft 70 and stop operating, and only the second motor MG2 maintains the second-gear output, effectively improving the driving efficiency.

[0059] When shifting from the second gear to the third gear, first switch the first shifting mechanism K1 to the second position, disengaging the first motor MG1 from the output shaft 70. At this time, the second motor MG2 maintains the second-gear output through the original power transmission route, keeping the power uninterrupted. Then, the fourth shifting mechanism K4 can be switched to the eighth position, and the power of the first motor MG1 sequentially passes through the first power output shaft 10 → second gear 11 → sixth gear 31 → second intermediate rotating shaft 30 → seventh gear 32 → twelfth gear 51 → first intermediate shaft 50 → thirteenth gear 52 → tenth gear 72 → output shaft 70. In this way, the first motor MG1 completes the upshift operation. During the upshift process, the power output route of the second motor MG2 always remains in the second-gear output route, and the power is not interrupted. After the first motor MG1 completes the gear shift, the third shifting mechanism K3 can first be switched to the seventh position, disengaging the second motor MG2 from the output shaft 70. Then, the second shifting mechanism K2 can be switched to the third position. In this way, the power of the first motor MG1 and the second motor MG2 can be simultaneously output through the third-gear output route, ensuring sufficient torque output. Of course, if the torque requirement is small, the second motor MG2 can also be disengaged from the output shaft 70 and stop operating, and only the first motor MG1 maintains the third-gear output, effectively improving the driving efficiency.

[0060] When shifting from the third gear to the fourth gear, the second shifting mechanism K2 can be first switched to the fourth position, and the second motor MG2 is disengaged from the output shaft 70. At this time, the first motor MG1 maintains the third-gear output through the original power transmission route, keeping the power uninterrupted. Then, the third shifting mechanism K3 is switched to the fifth position, and the power of the second motor MG2 sequentially passes through the second power output shaft 20 → the third gear 21 → the fourth gear 41 → the first intermediate rotating shaft 40 → the output shaft 70. In this way, the upshift operation is completed by the second motor MG2. During the upshift process, the power output route of the first motor MG1 always maintains the third-gear output route, and the power is not interrupted. After the second motor MG2 completes the gear shift, the fourth shifting mechanism K4 can be first switched to the tenth position. After the first motor MG1 is disengaged from the output shaft 70, the first shifting mechanism K1 can be switched to the first position. In this way, the power of the first motor MG1 and the second motor MG2 can be simultaneously output through the fourth-gear output route, ensuring sufficient torque output. Of course, if the torque requirement is small, the first motor MG1 can also remain disengaged from the output shaft 70 and stop running, and only the second motor MG2 maintains the fourth-gear output, effectively improving the driving efficiency.

[0061] Obviously, the technical solution provided in this embodiment avoids power interruption during gear shifting, effectively improving the shifting comfort and safety. At the same time, the dual-motor four-gear electric drive transmission system provided in this embodiment can select single-motor operation or dual-motor operation according to the torque requirement, which can effectively improve the driving efficiency.

[0062] In a further embodiment, the first intermediate shaft gear mechanism is provided with at least two, and is evenly distributed circumferentially with the output shaft 70 as the axis. The second intermediate shaft gear mechanism is provided with at least two, and is evenly distributed circumferentially with the output shaft 70 as the axis. For example, when the vehicle's rated load is large, both the first intermediate shaft gear mechanism and the second intermediate shaft gear mechanism can be set to two or three to improve the load-bearing capacity of the intermediate transmission mechanism.

[0063] It should be noted that in the above embodiment, the transmission ratios of the above-mentioned various gear pairs can be specifically set according to the actual situation, and no specific limitation will be given here.

[0064] In order to make the dual-motor four-gear electric drive transmission system provided in this embodiment have a reasonable layout, be structurally compact, and occupy a small volume, in a further embodiment, the first intermediate rotating shaft 40 and the output shaft 70 are coaxially arranged, and the second intermediate rotating shaft 30 is arranged between the fourth gear 41 and the fifth gear 42. Along the circumference of the output shaft 70, the gears on the first intermediate shaft gear mechanism and the gears on the second intermediate shaft gear mechanism are staggered. Along the axial direction of the output shaft 70, the second intermediate shaft gear mechanism is arranged between the twelfth gear 51 and the thirteenth gear 52. With such an arrangement, the transmission system provided in this embodiment has a compact and reasonable overall layout and occupies a small space.

[0065] In a further embodiment, the first motor MG1 and the second motor MG2 are respectively offset on both sides of the first intermediate shaft 40, and with the axis line of the first intermediate shaft 40 as the symmetric center line, the first motor MG1 and the second motor MG2 are symmetrically arranged. With such an arrangement, the layout of the two motors is compact and reasonable, occupying a smaller space.

[0066] In this embodiment, the first motor MG1 and the second motor MG2 are symmetrically offset inputs, which can improve the maximum speed of the dual motors and significantly reduce the motor torque requirements. The dual motors can significantly reduce weight and cost compared with a high-power single motor. The first intermediate shaft gear mechanism and the second intermediate shaft gear mechanism can adopt a symmetric dual intermediate shaft structure to meet the requirements of heavy-duty mechanical loads, or can also adopt a triple intermediate shaft structure to meet the requirements of overloaded mechanical loads. The two sets of intermediate shaft gear mechanisms are cleverly staggered in the circumferential direction of the central shaft, thereby establishing independent mechanical transmission paths for the two sets of motors, and establishing gear sharing for the two sets of motor drives, realizing efficient drive in the full vehicle speed range of the two motors. Since the dual motors have their own independent drive paths, during gear shifting, one motor maintains the current gear drive, and the other motor unloads and shifts gears, thereby realizing gear shifting control without power interruption, improving driving smoothness. And, when the driving condition has a low load demand, one motor can drive efficiently independently, and the other motor is only controlled during gear shifting and remains stationary and stopped in other conditions, which can improve the drive efficiency and increase the pure electric driving range.

[0067] Considering reliability and functional safety, the two sets of motor systems provide backup drive functions for each other. If one set of motor systems fails for some reason, the other set of motors can provide backup drive, thereby improving the reliability of the vehicle's electric drive system and also enhancing the safety function of the electric drive system. In particular, since the dual motors can evenly distribute the load, compared with the drive system of one set of motor systems, while improving the reliability, the load of the switching power module of the motor inverter is evenly distributed, and the current demand of the switching power module is significantly derated and matched, which is beneficial to improving the reliability of the electric drive power module and the overall system efficiency.

[0068] The transmission system provided in this embodiment is applicable to medium-duty trucks, medium-heavy trucks and heavy trucks with medium and heavy load requirements. The motor can directly use mass-produced high-speed, low-torque, low-cost passenger car drive motors, instead of using the low-speed, high-torque, high-cost, bulky special large-diameter motors widely used in heavy commercial vehicles. The passenger car motor has lower cost, better quality and higher reliability. The cost performance of this transmission system exceeds that of the single-motor heavy commercial vehicle electric drive assembly system.

[0069] This embodiment also provides a vehicle, including the dual-motor four-speed electric drive transmission system described in any of the foregoing embodiments. With this arrangement, the vehicle provided in this embodiment can solve the problem of power interruption during gear shifting. The derivation process of this beneficial effect is generally similar to the derivation process of the beneficial effect brought by the above dual-motor four-speed electric drive transmission system, and will not be elaborated here.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dual-motor four-speed electric drive transmission system, characterized in that, Comprising: A first motor (MG1); A second motor (MG2); A first power output shaft (10) drivingly connected to a power output end of the first motor (MG1), a first gear (12) being sleeved on the first power output shaft (10), and a second gear (11) being fixedly sleeved on the first power output shaft (10); A second power output shaft (20) drivingly connected to a power output end of the second motor (MG2), a third gear (21) being fixedly sleeved on the second power output shaft (20), and an eighth gear (22) being sleeved on the second power output shaft (20); A first intermediate shaft (40) having a fourth gear (41) and a fifth gear (42) fixedly sleeved thereon, wherein the fourth gear (41) is drivingly connected to the first gear (12) and the third gear (21) respectively; A second intermediate shaft (30) configured as a hollow shaft structure, the second intermediate shaft (30) being sleeved on an outer periphery of the first intermediate shaft (40), and a sixth gear (31) and a seventh gear (32) being fixedly sleeved on the second intermediate shaft (30), wherein the sixth gear (31) is drivingly connected to the second gear (11) and the eighth gear (22) respectively; An output shaft (70) having a ninth gear (71), a tenth gear (72) and an eleventh gear (73) sleeved thereon; A first intermediate shaft gear mechanism including a first intermediate shaft (50) and a twelfth gear (51), a thirteenth gear (52) and a fourteenth gear (53) fixedly sleeved on the first intermediate shaft (50), wherein the twelfth gear (51) is drivingly connected to the seventh gear (32), the thirteenth gear (52) is drivingly connected to the tenth gear (72), and the fourteenth gear (53) is drivingly connected to the eleventh gear (73); A second intermediate shaft gear mechanism including a second intermediate shaft (60) and a fifteenth gear (61) and a sixteenth gear (62) fixedly sleeved on the second intermediate shaft (60), wherein the fifteenth gear (61) is drivingly connected to the fifth gear (42), and the sixteenth gear (62) is drivingly connected to the ninth gear (71); A first shifting mechanism (K1) capable of switching between a first position and a second position, in the first position, the first power output shaft (10) is coupled to the first gear (12), and in the second position, the first power output shaft (10) is disengaged from the first gear (12); A second shifting mechanism (K2) capable of switching between a third position and a fourth position, in the third position, the second power output shaft (20) is coupled to the eighth gear (22), and in the fourth position, the second power output shaft (20) is disengaged from the eighth gear (22); The third shifting mechanism (K3) is capable of switching between a fifth position, a sixth position, and a seventh position. In the fifth position, the first intermediate rotating shaft (40) is coupled to the output shaft (70). In the sixth position, the output shaft (70) is coupled to the ninth gear (71). In the seventh position, the output shaft (70), the first intermediate rotating shaft (40), and the ninth gear (71) are disengaged from each other. The fourth shifting mechanism (K4) is capable of switching between an eighth position, a ninth position, and a tenth position. In the eighth position, the output shaft (70) is coupled to the tenth gear (72). In the ninth position, the output shaft (70) is coupled to the eleventh gear (73). In the tenth position, the output shaft (70), the tenth gear (72), and the eleventh gear (73) are disengaged from each other.

2. The dual-motor four-speed electric drive transmission system according to claim 1, characterized in that, The first intermediate shaft gear mechanism is provided with at least two and is evenly distributed circumferentially with the output shaft (70) as the axis.

3. The dual-motor four-speed electric drive transmission system according to claim 1 or 2, characterized in that, The second intermediate shaft gear mechanism is provided with at least two and is evenly distributed circumferentially with the output shaft (70) as the axis.

4. The dual-motor four-speed electric drive transmission system according to claim 1, wherein, The first intermediate rotating shaft (40) and the output shaft (70) are coaxially arranged.

5. The dual-motor four-speed electric drive transmission system according to claim 4, characterized in that, The first motor (MG1) and the second motor (MG2) are respectively offset on both sides of the first intermediate rotating shaft (40).

6. The dual-motor four-speed electric drive transmission system according to claim 5, wherein Taking the axis of the first intermediate rotating shaft (40) as the symmetric center line, the first motor (MG1) and the second motor (MG2) are symmetrically arranged.

7. The dual-motor four-speed electric drive transmission system according to claim 1, characterized in that The second intermediate rotating shaft (30) is arranged between the fourth gear (41) and the fifth gear (42).

8. The dual-motor four-speed electric drive transmission system according to claim 1, characterized in that, Along the circumferential direction of the output shaft (70), the gears on the first intermediate shaft gear mechanism and the gears on the second intermediate shaft gear mechanism are staggered.

9. The dual-motor four-speed electric drive transmission system according to claim 1, characterized in that Along the axial direction of the output shaft (70), the second intermediate shaft gear mechanism is arranged between the twelfth gear (51) and the thirteenth gear (52).

10. A vehicle, characterized in that, It includes a dual-motor four-speed electric drive transmission system according to any one of claims 1-9.

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