Electric motor driving system and vehicle

Abstract

An electric motor driving system and a vehicle. The electric motor driving system comprises a first electric motor, a second electric motor, a first clutch, a first intermediate shaft and a second intermediate shaft, wherein one end of the first intermediate shaft is in transmission connection with the first electric motor, one end of the second intermediate shaft is in transmission connection with the second electric motor, the other end of the first intermediate shaft is connected to the other end of the second intermediate shaft by means of the first clutch, and the first clutch is configured to engage or disengage the first intermediate shaft with or from the second intermediate shaft; a differential mechanism which comprises an input end, a first output end and a second output end, wherein the input end is in transmission connection with the first intermediate shaft; a second clutch which is connected to the second intermediate shaft and the second output shaft and is configured to engage or disengage the second intermediate shaft with or from the second output shaft; and a third clutch which is connected to the first output shaft and the second output shaft and is configured to engage or disengage the first output shaft with or from the second output shaft. Torque distribution of different proportions can be performed between the electric motors, and the electric motor efficiency is improved.

Description

Motor drive system and vehicle

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on January 17, 2024, with application number 202410070518.6 and titled “Motor Drive System and Vehicle”, and claims priority to the Chinese patent application filed with the China Patent Office on January 17, 2024, with application number 202420119070.8 and titled “Motor Drive System and Vehicle”. The entire contents of the foregoing priorities are incorporated by reference into this application. Technical Field

[0002] The present application belongs to the field of motor technology, and specifically relates to a motor drive system and a vehicle. Background Art

[0003] Distributed drive has become a hot topic in the current research of electric drive systems. It consists of two or more drive motors that independently drive their respective wheels, while reducing the power and torque requirements of a single motor, which is more conducive to the system's integrated, lightweight and modular design.

[0004] However, in traditional distributed electric drive configurations, the left and right motors drive the left and right wheels separately. In most driving conditions, the torque requirements of the left and right wheels are the same, so in most cases the torque is distributed 50% to each of the left and right motors, which reduces motor efficiency. Summary of the Invention

[0005] The purpose of this application is to provide a motor drive system and a vehicle, in which torque can be distributed in different proportions between motors to improve motor efficiency.

[0006] The first aspect of the present application discloses a motor drive system, comprising:

[0007] a first motor, a second motor, and a first clutch;

[0008] a first intermediate shaft and a second intermediate shaft, one end of the first intermediate shaft being transmission-connected to the first motor, one end of the second intermediate shaft being transmission-connected to the second motor, the other end of the first intermediate shaft and the other end of the second intermediate shaft being connected via the first clutch, the first clutch being used to engage or disengage the first intermediate shaft and the second intermediate shaft;

[0009] a differential, the differential comprising an input end, a first output end, and a second output end, the input end being drivingly connected to the first intermediate shaft, the first output end being connected to a first wheel via a first output shaft, and the second output end being connected to a second wheel via a second output shaft;

[0010] a second clutch connected to the second intermediate shaft and the second output shaft, for coupling or disengaging the second intermediate shaft and the second output shaft;

[0011] The third clutch is connected to the first output shaft and the second output shaft, and is used to connect or disconnect the first output shaft and the second output shaft.

[0012] In an exemplary embodiment of the present disclosure, the motor drive system further includes a differential lock connected to the differential and configured to connect or disconnect the first output end and the second output end.

[0013] In an exemplary embodiment of the present disclosure, the first motor has a first motor output shaft, and the first motor output shaft is connected to the first intermediate shaft through a first gear transmission device.

[0014] In an exemplary embodiment of the present disclosure, the first gear transmission device includes at least a first gear provided on the output shaft of the first motor and a second gear provided on the first intermediate shaft, and the first gear and the second gear are meshed.

[0015] In an exemplary embodiment of the present disclosure, the second motor has a second motor output shaft, and the second motor output shaft is connected to the second intermediate shaft through a second gear transmission device.

[0016] In an exemplary embodiment of the present disclosure, the second gear transmission device includes at least a third gear provided on the second motor output shaft and a fourth gear provided on the second intermediate shaft, and the third gear is meshed with the fourth gear.

[0017] In an exemplary embodiment of the present disclosure, a fifth gear is provided on the second output shaft, one end of the second clutch is connected to a sixth gear, and the other end is connected to the second intermediate shaft, and the fifth gear is meshed with the sixth gear.

[0018] In an exemplary embodiment of the present disclosure, the input end of the differential is connected to a seventh gear, an eighth gear is provided on the first intermediate shaft, and the seventh gear is meshed with the eighth gear.

[0019] In an exemplary embodiment of the present disclosure, the first intermediate shaft and the second intermediate shaft are coaxially disposed, and the first clutch is disposed at the center of the axes of the first intermediate shaft and the second intermediate shaft.

[0020] The second aspect of the present application further discloses a vehicle, comprising the motor drive system.

[0021] This application has the following beneficial effects:

[0022] In the present application, by controlling the engagement or disengagement of the first clutch, the second clutch, and the third clutch, the torque of the first motor and the second motor can be uniformly transmitted to the first wheel and the second wheel. At this time, the first motor and the second motor can select different torques, and different proportions of torque can be distributed between the first motor and the second motor, so that the motor can obtain better driving efficiency, thereby obtaining better economy.

[0023] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by practice of the present application.

[0024] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0026] FIG1 shows a schematic structural diagram of the connection between the motor drive system and the wheels provided in Example 1 of the present application.

[0027] Description of reference numerals:

[0028] First motor 1, second motor 2, first clutch 3, second clutch 4, differential lock 5, third clutch 6, differential 7, first motor output shaft 8, first gear 9, second gear 10, first intermediate shaft 11, second intermediate shaft 12, third gear 13, fourth gear 14, fifth gear 15, sixth gear 16, seventh gear 17, eighth gear 18, second motor output shaft 19, first output shaft 20, second output shaft 21, first wheel 22, second wheel 23. DETAILED DESCRIPTION

[0029] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art.

[0030] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise specifically specified.

[0031] In this application, unless otherwise specified or limited, terms such as "assembly" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0032] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner.In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps etc. can be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0033] 1 , an embodiment of the present disclosure discloses a motor drive system, which includes a first motor 1 , a second motor 2 , a first intermediate shaft 11 , a second intermediate shaft 12 , a differential 7 , a first clutch 3 , a second clutch 4 , and a third clutch 6 .

[0034] In some embodiments, the first motor 1 is transmission-connected to one end of the first intermediate shaft 11, and the first motor 1 transmits power to the first intermediate shaft 11. The second motor 2 is transmission-connected to one end of the second intermediate shaft 12, and the second motor 2 transmits power to the second intermediate shaft 12. The other end of the first intermediate shaft 11 and the other end of the second intermediate shaft 12 are connected via a first clutch 3, which is used to connect or disconnect the first intermediate shaft 11 and the second intermediate shaft 12. When the first clutch 3 is engaged, the first intermediate shaft 11 and the second intermediate shaft 12 form a whole, and the power of the first motor 1 and the power of the second motor 2 are combined and transmitted to the first intermediate shaft 11 and the second intermediate shaft 12; when the first clutch 3 is disengaged, the power of the first motor 1 and the second motor 2 are transmitted to the first intermediate shaft 11 and the second intermediate shaft 12, respectively, without affecting each other.

[0035] In some embodiments, the first motor 1 and the second motor 2 can be connected to power batteries respectively, which provide the first motor 1 and the second motor 2 with the electric energy required for driving. At the same time, the electric energy generated when the first motor 1 and the second motor 2 are driven to rotate can also be stored in the power battery.

[0036] It can be understood that the inner hub of the first clutch 3 can be connected to one end of the first intermediate shaft 11 or one end of the second intermediate shaft 12, and accordingly, the outer hub of the first clutch 3 can be connected to one end of the second intermediate shaft 12 or one end of the first intermediate shaft 11.

[0037] In some embodiments, the first intermediate shaft 11 and the second intermediate shaft 12 are coaxially arranged. When the first clutch 3 is engaged, the first intermediate shaft 11 and the second intermediate shaft 12 form a single intermediate shaft, facilitating power transmission. Furthermore, the first motor 1 and the second motor 2 can be respectively arranged on either side of the first intermediate shaft 11 and the second intermediate shaft 12, thereby integrating them into a single housing, resulting in a more compact structure and easier layout. The first clutch 3 is disposed at the center of the axes of the first intermediate shaft 11 and the second intermediate shaft 12.

[0038] In some embodiments, the first motor 1 has a first motor output shaft 8, which is connected to the first intermediate shaft 11 via a first gear transmission. This connection via the first gear transmission is easy to implement and has a simple structure. It also achieves a desired transmission ratio and provides reliable transmission. The first gear transmission includes at least a first gear 9 disposed on the first motor output shaft 8 and a second gear 10 disposed on the first intermediate shaft 11. The first gear 9 and the second gear 10 mesh with each other. The transmission ratio of the first gear transmission can be controlled by controlling the number of teeth on the first gear 9 and the second gear 10. Of course, the first gear transmission can also include more transmission gears to achieve different transmission ratios.

[0039] Similarly, the second motor 2 has a second motor output shaft 19, which is connected to the second intermediate shaft 12 via a second gear transmission. The second gear transmission includes at least a third gear 13 disposed on the second motor output shaft 19 and a fourth gear 14 disposed on the second intermediate shaft 12. The third gear 13 and the fourth gear 14 are meshed. The transmission ratio of the second gear transmission can be controlled by controlling the gear ratios of the third gear 13 and the fourth gear 14. Of course, the second gear transmission can also include more transmission gears to achieve different transmission ratios.

[0040] It is understandable that the first gear transmission device and the second gear transmission device can adopt the same gear structure configuration to improve the versatility of the gears, and the motor drive system has a high degree of symmetry to avoid the center of gravity from deviating excessively to one side.

[0041] In some embodiments, a fifth gear 15 is provided on the second output shaft 21. One end of the second clutch 4 is connected to the sixth gear 16, and the other end is connected to the second intermediate shaft 12. The sixth gear 16 and the fifth gear 15 are meshed, thereby connecting and disconnecting the second output shaft 21 and the second intermediate shaft 12 using the fifth gear 15, the sixth gear 16, and the second clutch 4. The outer hub of the second clutch 4 can be connected to the second intermediate shaft 12, and the inner hub of the second clutch 4 can be connected to the sixth gear 16.

[0042] In some embodiments, the differential 7 includes an input, a first output, and a second output. The input of the differential 7 is drivingly connected to the first intermediate shaft 11. The first output is connected to a first wheel 22 via a first output shaft 20, and the second output is connected to a second wheel 23 via a second output shaft 21. The first wheel 22 and the second wheel 23 are arranged in a pair. For example, the first wheel 22 and the second wheel 23 are each one of the front wheels of the vehicle, or each one of the rear wheels of the vehicle. Power is transmitted to the differential 7 via the first intermediate shaft 11, and ultimately to the first wheel 22 and the second wheel 23, thereby driving the vehicle.

[0043] It is understood that when a vehicle turns, the turning radius of the inner and outer wheels differs, with the outer wheel's turning radius being larger than the inner wheel's. This requires that the outer wheel's rotational speed be higher than that of the inner wheel during a turn. The differential 7 is a mechanism that enables the inner and outer wheels to rotate at different speeds. The differential 7 is comprised of components such as planetary gears, a planetary carrier, and axle gears. Power enters the differential 7 via an input shaft, directly driving the planetary carrier, which in turn drives the left and right axles to drive the inner and outer wheels, respectively. The input shaft is the input end of the differential 7, and the first and second output ends can be either the left or right axles, respectively. During a turn, the first wheel 22 and the second wheel 23 are either the inner or outer wheels, respectively. The specific structure and operating principle of the differential 7 are not detailed here.

[0044] In some embodiments, the input end of the differential 7 is connected to a seventh gear 17, and an eighth gear 18 is provided on the first intermediate shaft 11. The seventh gear 17 and the eighth gear 18 engage to transmit power from the first intermediate shaft 11 to the differential 7. The eighth gear 18 and the sixth gear 16 can be symmetrically arranged relative to the first clutch 3 to achieve better symmetry for the motor drive system, avoid center of gravity shift, and improve the reliability of the motor drive system.

[0045] In some embodiments, the motor drive system further includes a differential lock 5 connected to the differential 7 for engaging or disengaging the first output terminal and the second output terminal. By providing the differential lock 5, the differential 7 becomes a positive locking differential 7. When one wheel slips, the differential lock 5 can be used to lock the differential 7, preventing it from performing a differential function. This allows most, or even all, of the torque to be transferred to the other wheel on a good road surface, thereby fully utilizing the adhesion of the wheel on this side to generate sufficient driving force, allowing the vehicle to escape and continue driving. Depending on their structural characteristics, the combination of the differential lock 5 and the differential 7 includes positive locking, high friction, and freewheel types. Among the high friction types, friction plate self-locking differentials 7, Torsen differentials 7, worm gear differentials 7, slider cam differentials 7, and viscous coupling differentials 7 are widely used in vehicles. The connection and operating principles of the differential lock 5 and the differential 7 are not further described here.

[0046] In some embodiments, the second clutch 4 is connected to the second intermediate shaft 12 and the second output shaft 21, and is used to connect or disconnect the second intermediate shaft 12 and the second output shaft 21. When the second clutch 4 is engaged, the power output by the second motor 2 is transmitted to the second output shaft 21 via the second intermediate shaft 12 to drive the second wheel 23. When the second clutch 4 is disengaged, the second intermediate shaft 12 and the second output shaft 21 are disconnected.

[0047] In some embodiments, the third clutch 6 is connected to the first output shaft 20 and the second output shaft 21 for coupling or disengaging the first output shaft 20 and the second output shaft 21. When the third clutch 6 is engaged, the first output shaft 20 and the second output shaft 21 are coupled, and the speeds of the first and second wheels 22 and 23 can be controlled via the differential 7. When the third clutch 6 is disengaged, the first and second output shafts 20 and 21 are separated, and the second wheel 23 can be directly controlled by the second motor 2 via the second intermediate shaft 12 and the second output shaft 21.

[0048] In this embodiment, by controlling the first clutch 3 to engage, the second clutch 4 to disengage, and the third clutch 6 to engage, the torque of the first motor 1 and the second motor 2 can be uniformly transmitted to the first wheel 22 and the second wheel 23, and the first motor 1 and the second motor 2 can jointly drive the first wheel 22 and the second wheel 23. At this time, the first motor 1 and the second motor 2 can select different torques, and different proportions of torque can be distributed between the first motor 1 and the second motor 2, so that the motors can obtain better driving efficiency, thereby obtaining better economy.

[0049] Therefore, the motor drive system in this embodiment has a pure electric distributed drive mode, a single motor drive mode, a pure electric escape mode and a dual motor torque distribution drive mode.

[0050] In pure electric distributed drive mode, the first clutch 3 is disengaged, the second clutch 4 is engaged, and the third clutch 6 is disengaged, thereby disengaging the first intermediate shaft 11 and the second intermediate shaft 12, and disengaging the first output shaft 20 and the second output shaft 21. When the first motor 1 and the second motor 2 are operating, they drive the first intermediate shaft 11 and the second intermediate shaft 12, respectively, thereby driving the first wheel 22 and the second wheel 23 via the first output shaft 20 and the second output shaft 21, respectively. In this mode, since the first wheel 22 and the second wheel 23 are independently driven by the first motor 1 and the second motor 2, respectively, the power and torque requirements of each motor are reduced, significantly improving the vehicle's maneuverability. The differential lock 5 can engage or disengage the differential 7. In this embodiment, the differential lock 5 is engaged with the differential 7 to achieve better power transmission.

[0051] In single-motor drive mode, if the second motor 2 fails and cannot operate, the first clutch 3 can be disengaged, the second clutch 4 can be disengaged, the third clutch 6 can be engaged, and the differential lock 5 can be disengaged, thereby separating the first intermediate shaft 11 and the second intermediate shaft 12, and the second intermediate shaft 12 and the second output shaft 21 can be disengaged, and the differential 7 can be operated. When the first motor 1 is in operation, the first intermediate shaft 11 transmits power to the differential 7, thereby driving the first output shaft 20 and the second output shaft 21, respectively, to drive the first wheel 22 and the second wheel 23, thus realizing single-motor drive vehicle operation. Of course, by the same token, the second motor 2 can also drive the first wheel 22 and the second wheel 23. In this case, if the first motor 1 fails and cannot be used, the first clutch 3 can be engaged, the second clutch 4 can be disengaged, the third clutch 6 can be engaged, and the differential lock 5 can be disengaged.

[0052] In the pure electric escape mode, the first clutch 3 is engaged, the second clutch 4 is disengaged, the third clutch 6 is engaged, and the differential lock 5 is engaged, so that the first intermediate shaft 11 and the second intermediate shaft 12 are engaged, the first output shaft 20 and the second output shaft 21 are engaged, and the second intermediate shaft 12 and the second output shaft 21 are disengaged. The torque of the first motor 1 and the second motor 2 is uniformly transmitted to the seventh gear 17, and the differential 7 is locked by the differential lock 5. When the first wheel 22 slips, the second wheel 23 is driven together. When the second wheel 23 slips, the first wheel 22 is driven together, so that the vehicle can escape from trouble and continue to drive normally.

[0053] In the dual-motor torque distribution drive mode, the first clutch 3 is engaged, the second clutch 4 is disengaged, the third clutch 6 is engaged, and the differential lock 5 is disengaged, so that the first intermediate shaft 11 and the second intermediate shaft 12 are connected, the first output shaft 20 and the second output shaft 21 are connected, the second intermediate shaft 12 and the second output shaft 21 are disengaged, and the torque of the first motor 1 and the second motor 2 is uniformly transmitted to the seventh gear 17, and the torque is transmitted to the first wheel 22 and the second wheel 23 through the differential 7. At this time, the first motor 1 and the second motor 2 can select different torques, and different proportions of torque can be distributed between the first motor 1 and the second motor 2, so that the motors can obtain better driving efficiency, thereby obtaining better economy and improving vehicle endurance.

[0054] For example, when the total torque required by the motor is T and the speed is n, in the pure electric distributed drive mode, the torque of the first motor 1 and the second motor 2 is T / 2 respectively. Assuming the efficiency is η1, the required power p1 = T*n / η1 / 9549, where 9549 is a constant coefficient.

[0055] In the dual-motor torque distribution driving mode, in this embodiment, the torque of the first motor 1 and the second motor 2 can be distributed according to the actual working conditions. Assuming that the distribution ratio of the first wheel 22 is k, the corresponding torque is k*T, and the corresponding efficiency is η2, then the second wheel 23 is distributed as (1-k)*T, and the corresponding efficiency is η3. The required power p2 = k*T*n / (9549*η2)+(1-k)*T*n / (9549*η3), where K can be 20%, 30% or 40%, etc., and is distributed in the most economical way.

[0056] The above-mentioned various working modes are specifically reflected in a table, as shown in Table 1 below:

[0057] Table 1

[0058] In summary, the overall structure of the motor drive system of the present application is simple, compact, and easy to arrange. It can realize multiple operating modes according to the different states of the first clutch 3, the second clutch 4, the third clutch 6, and the differential lock 5. The operating mode can be switched according to actual needs, such as switching to a pure electric distributed drive mode for better controllability, or switching to a dual-motor torque distribution drive mode for better economy. At the same time, it can also switch to an escape mode to escape the distress and continue driving when the vehicle is trapped, and use the other motor to continue to drive the drive system when one of the motors fails.

[0059] This embodiment further provides a vehicle including the aforementioned motor drive system. It should be understood that other components of the vehicle according to this embodiment, such as the driving system, steering system, and braking system, are already known in the prior art and are well known to those skilled in the art. Therefore, a detailed description of the known components is omitted here.

[0060] In the description of this specification, the reference terms "some embodiments", "exemplarily", etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0061] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application. Therefore, any changes or modifications made in accordance with the claims and description of the present application should fall within the scope of the patent application.

Claims

1. A motor drive system, characterized in that, Comprising: A first motor, a second motor, and a first clutch; A first intermediate shaft and a second intermediate shaft, one end of the first intermediate shaft is drivingly connected to the first motor, one end of the second intermediate shaft is drivingly connected to the second motor, the other end of the first intermediate shaft and the other end of the second intermediate shaft are connected by the first clutch, and the first clutch is used to couple or decouple the first intermediate shaft and the second intermediate shaft; A differential, the differential includes an input end, a first output end, and a second output end, the input end is drivingly connected to the first intermediate shaft, the first output end is connected to a first wheel through a first output shaft, and the second output end is connected to a second wheel through a second output shaft; A second clutch, connected to the second intermediate shaft and the second output shaft, and used to couple or decouple the second intermediate shaft and the second output shaft; A third clutch, connected to the first output shaft and the second output shaft, and used to couple or decouple the first output shaft and the second output shaft.

2. The motor drive system according to claim 1, wherein: The motor drive system further includes a differential lock, the differential lock is connected to the differential and is used to couple or decouple the first output end and the second output end.

3. The motor drive system according to claim 1, wherein: The first motor has a first motor output shaft, and the first motor output shaft is connected to the first intermediate shaft through a first gear transmission device.

4. The motor drive system according to claim 3, wherein: The first gear transmission device at least includes a first gear disposed on the first motor output shaft and a second gear disposed on the first intermediate shaft, and the first gear and the second gear are meshed.

5. The motor drive system according to claim 1, wherein: The second motor has a second motor output shaft, and the second motor output shaft is connected to the second intermediate shaft through a second gear transmission device.

6. The motor drive system according to claim 5, wherein: The second gear transmission device at least includes a third gear disposed on the second motor output shaft and a fourth gear disposed on the second intermediate shaft, and the third gear and the fourth gear are meshed.

7. The motor drive system according to claim 1, wherein: A fifth gear is disposed on the second output shaft, one end of the second clutch is connected to a sixth gear, and the other end is connected to the second intermediate shaft, and the fifth gear and the sixth gear are meshed.

8. The motor drive system according to claim 1, wherein: The input end of the differential is connected to a seventh gear, an eighth gear is disposed on the first intermediate shaft, and the seventh gear and the eighth gear are meshed.

9. The motor drive system according to claim 1, wherein: The first intermediate shaft and the second intermediate shaft are coaxially disposed, and the first clutch is disposed at the center on the axis of the first intermediate shaft and the second intermediate shaft.

10. A vehicle, characterized in that, Including the motor drive system according to any one of claims 1 to 9.

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