Power driving system, four-wheel driving power system and vehicle

Abstract

The invention provides a power drive system, a four-wheel drive power system and a vehicle, the power drive system comprises a first drive assembly, a second drive assembly and a power assisting mechanism, the first drive assembly is in power connection with a first wheel, the second drive assembly is in power connection with a second wheel, and the first wheel and the second wheel are located on the front portion or the rear portion of the vehicle; the power assisting mechanism comprises a driving source, a first transmission assembly and a second transmission assembly, the driving source is selectively connected with the first driving assembly through the first transmission assembly, the driving source is selectively connected with the second driving assembly through the second transmission assembly, and the power output directions of the first transmission assembly and the second transmission assembly are different. According to the power driving system, the torque output of the first wheel and the torque output of the second wheel are enhanced by arranging the power assisting mechanism, the function of turning around in situ can be achieved by outputting opposite acting force, the torque requirement for the first driving assembly and the torque requirement for the second driving assembly are reduced, and therefore the size, the weight and the cost are reduced.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a power drive system, a four-wheel drive system and a vehicle. Background Art

[0002] The torque and speed of the four wheels of a four-wheel independent drive vehicle can be precisely controlled independently of each other, achieving functions that traditional vehicles do not have.

[0003] In the prior art, when realizing some special functions under various road conditions and loads, the vehicle needs to output a larger torque. Therefore, when the larger torque output needs to be provided by the drive motor, the overall structure of the drive motor becomes large in size, heavy in weight, and high in cost. Summary of the Invention

[0004] The present invention aims to address at least one of the technical problems existing in the prior art. To this end, one objective of the present invention is to provide a power drive system that, by providing a power assist mechanism, enhances the torque output of the first and second wheels. The output of opposing forces enables a unique function of turning on the spot, while also reducing the torque requirements of the first and second drive assemblies, thereby reducing size, weight, and cost.

[0005] According to an embodiment of the present invention, the power drive system includes: a first drive component, a second drive component and a power assist mechanism, the first drive component is connected to the power of the first wheel, and the second drive component is connected to the power of the second wheel, wherein the first wheel and the second wheel are located at the front or rear of the vehicle; the power assist mechanism includes a drive source, a first transmission component and a second transmission component, the drive source is selectively connected to the first drive component through the first transmission component, and the drive source is selectively connected to the second drive component through the second transmission component, wherein the power output directions of the first transmission component and the second transmission component are different.

[0006] According to the power drive system of an embodiment of the present invention, the power assist mechanism simultaneously assists the first and second drive assemblies, thereby outputting greater torque to the first and second wheels and reducing the torque requirements of the first and second drive assemblies, thereby reducing the size, weight, and cost of the motors. Furthermore, the output directions are opposite, so this design allows the power assist mechanism to operate and transmit a portion of the torque in a positive direction to the first wheel on one side of the vehicle, while the remaining portion of the torque can be transmitted in a negative direction to the second wheel on the other side. This can simultaneously enhance the torque of both wheels, reducing the power requirements of the first and second drive assemblies while meeting the functional requirements of the vehicle's U-turn.

[0007] According to the power drive system of the embodiment of the present invention, the speed ratio between the drive source and the first wheel is a, and the speed ratio between the drive source and the second wheel is b, and a>100, b>100 is satisfied.

[0008] According to the power drive system of the embodiment of the present invention, the speed ratio of the drive source to the first wheel is a, the speed ratio of the drive source to the second wheel is b, and they satisfy: a=b.

[0009] According to the power drive system of an embodiment of the present invention, the first drive component includes a first motor and a first reducer, the first transmission component and the first motor are suitable for jointly transmitting power to the first reducer, and transmitting the power to the first wheel through the first reducer; the second drive component includes a power-connected second motor and a second reducer, the second transmission component and the second motor are suitable for jointly transmitting power to the second reducer, and transmitting the power to the second wheel through the second reducer.

[0010] According to the power drive system of an embodiment of the present invention, when the vehicle is in a driving condition, the speed range of the first motor is controlled to be in a high-efficiency operating area, and / or the speed range of the second motor is controlled to be in a high-efficiency operating area.

[0011] According to the power drive system of an embodiment of the present invention, when the vehicle is in a U-turn condition, the drive source is controlled to output a first maximum torque, and the first motor is controlled to output a first residual torque, wherein the speed ratio of the drive source output to the first wheel is a first speed ratio, and the speed ratio of the first motor output to the first wheel is a second speed ratio, and the first residual torque = (U-turn torque requirement - first maximum torque * first speed ratio) / second speed ratio.

[0012] According to the power drive system of an embodiment of the present invention, when the vehicle is in a U-turn condition, the drive source is controlled to output the second maximum torque, and the second motor is controlled to output the second residual torque, wherein the speed ratio of the drive source output to the second wheel is the third speed ratio, and the speed ratio of the second motor output to the second wheel is the fourth speed ratio, and the second residual torque = (U-turn torque requirement - second maximum torque * third speed ratio) / fourth speed ratio.

[0013] According to the power drive system of an embodiment of the present invention, the first motor is provided with a first output shaft, the second motor is provided with a second output shaft, the first output shaft and the wheel axle of the vehicle are coaxially distributed, and the second output shaft and the wheel axle of the vehicle are coaxially distributed.

[0014] According to the power drive system of an embodiment of the present invention, the first motor is provided with a first output shaft, the second motor is provided with a second output shaft, the first output shaft and the wheel axle of the vehicle are parallel and spaced apart, and the second output shaft and the wheel axle of the vehicle are parallel and spaced apart.

[0015] According to the power drive system of an embodiment of the present invention, the output end of the power-assisting mechanism is selectively connected to the first reducer and / or the second reducer to selectively transmit power to the first wheel and / or the second wheel.

[0016] According to the power drive system of an embodiment of the present invention, the output end of the power assist mechanism is selectively connected to the first motor and / or the second motor to selectively transmit power to the first wheel and / or the second wheel.

[0017] According to the power drive system of an embodiment of the present invention, the first transmission assembly includes a first gear pair and a first coupling-disconnecting device, the driving source outputs power to the first gear pair, and the first gear pair is selectively connected to the first drive assembly through the first coupling-disconnecting device; the second transmission assembly includes a second gear pair and a second coupling-disconnecting device, the driving source outputs power to the second gear pair, and the second gear pair is selectively connected to the second drive assembly through the second coupling-disconnecting device.

[0018] According to an embodiment of the present invention, the power drive system includes: when the first wheel is suspended or has insufficient adhesion and the second wheel can travel normally, the first coupling disconnecting device is controlled to be in a disconnected state, and the second coupling disconnecting device is controlled to be in a coupled state, and the power of the power assist mechanism and the second drive assembly is transmitted together to the second wheel; when the second wheel is suspended or has insufficient adhesion and the first wheel can travel normally, the first coupling disconnecting device is controlled to be in a coupled state, and the second coupling disconnecting device is controlled to be in a disconnected state, and the power of the power assist mechanism and the first drive assembly is transmitted together to the first wheel; when both the first wheel and the second wheel are on the ground but have insufficient power, the first coupling disconnecting device is controlled to be in a coupled state, and the second coupling disconnecting device is controlled to be in a coupled state, and the power of the power assist mechanism and the first drive assembly is output together to the first wheel, and the power of the power assist mechanism and the second drive assembly is output together to the second wheel.

[0019] An embodiment of the present invention further provides a four-drive power system, comprising two sets of the above-mentioned power drive systems, wherein one set of the power drive systems is disposed at the front of the vehicle, and the other set of the power drive systems is disposed at the rear of the vehicle.

[0020] That is, when a vehicle makes a U-turn on the spot, the power requirements of the front and rear wheels are different. During the U-turn process, the front wheels need to maintain a certain amount of grip, preferably with additional grip, while the rear wheels need to lose most or all of their grip to produce a drifting effect. Specifically, the four-wheel drive system can independently control the driving force of each wheel according to the vehicle's motion state, thereby achieving precise driving force distribution. When a U-turn is required on the spot, the system will mainly distribute the driving force to the front wheels, while reducing the driving force to the rear wheels, causing the rear wheels to lose most or all of their grip, thereby achieving a drifting effect. If both the front and rear wheels of the four-wheel drive system are equipped with power-assisting mechanisms, one set of power-assisting mechanisms can be used to assist the front wheels, and another set of power-assisting mechanisms can be used to assist the rear wheels. When outputting a large torque, the power requirements of the first and second drive assemblies corresponding to the rear wheels can be reduced, and the power requirements of the first and second drive assemblies corresponding to the front wheels can also be reduced.

[0021] According to the four-drive power system of an embodiment of the present invention, the drive source of each group of the power drive system is connected to the first drive component through the first transmission component, and is connected to the second drive component through the second transmission component. The first drive component located on one side of the vehicle drives the first wheel to rotate in a first direction, and the second drive component located on the other side of the vehicle drives the second wheel to rotate in a second direction.

[0022] According to the four-drive power system of an embodiment of the present invention, the drive source of one group of the power drive systems disconnects power transmission from the first wheel and transmits power to the second wheel, and the drive source of another group of the power drive systems simultaneously transmits power to the first wheel and the second wheel.

[0023] An embodiment of the present invention further provides a vehicle, comprising the above-mentioned power drive system or the above-mentioned four-wheel drive system.

[0024] The advantages of the vehicle described above are the same as those of the power drive system and the four-wheel drive system, which will not be described in detail here.

[0025] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments with reference to the following drawings, in which:

[0027] Figure 1 This is a schematic diagram of the structure of the first embodiment of the power drive system of the present invention. Figure 1 ;

[0028] Figure 2 This is a schematic diagram of the structure of the first embodiment of the power drive system of the present invention. Figure 2 ;

[0029] Figure 3 is a schematic structural diagram of a second embodiment of the power drive system of the present invention;

[0030] Figure 4 is a schematic structural diagram of a third embodiment of the power drive system of the present invention;

[0031] Figure 5 2 is a schematic structural diagram of a fourth embodiment of the power drive system of the present invention.

[0032] Reference numerals:

[0033] Power drive system 100,

[0034] First motor 1, second motor 2, first reducer 3, first output gear 31, second output gear 32, third output gear 33, fourth output gear 34, first sun gear 35, first planetary gear 36, first planetary ring gear 37, first planetary carrier 38, second reduction mechanism 4, fifth output gear 41, sixth output gear 42, seventh output gear 43, eighth output gear 44, second sun gear 45, second planetary gear 46, second planetary ring gear 47, second planetary carrier 48, power assist mechanism 5, drive source 51, first gear pair 52, first power assist gear 521, second power assist gear 522, second gear pair 53, third power assist gear 531, fourth power assist gear 532, fifth power assist gear 533, first coupling and disconnecting device 6, second coupling and disconnecting device 7, first wheel 8, second wheel 9, wheel axle 10. DETAILED DESCRIPTION

[0035] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0036] refer to Figure 1-Figure 5 The power drive system 100 according to an embodiment of the present invention is described. By providing a power assist mechanism 5, the torque output of the first wheel 8 and the second wheel 9 is enhanced. When realizing the special function of turning around on the spot, opposite forces are output, and the torque requirements for the first drive component and the second drive component are reduced, thereby reducing the volume, weight and cost.

[0037] The embodiment of the present invention provides a power drive system 100 , comprising: a first drive assembly, a second drive assembly and a power assist mechanism 5 .

[0038] Among them, the first drive assembly is power-connected to the first wheel 8, the second drive assembly is power-connected to the second wheel 9, and the first wheel 8 and the second wheel 9 are located at the front or rear of the vehicle; the power-assisting mechanism 5 includes a drive source 51, a first transmission assembly and a second transmission assembly, the drive source 51 is selectively connected to the first drive assembly through the first transmission assembly, and the drive source 51 is selectively connected to the second drive assembly through the second transmission assembly, wherein the power output directions of the first transmission assembly and the second transmission assembly are different.

[0039] In practice, one of the first wheel 8 and the second wheel 9 is a left wheel and the other is a right wheel. The first drive assembly is power-connected to the first wheel 8 and is used to drive the rotation of the first wheel 8. The second drive assembly is power-connected to the second wheel 9 and is used to drive the rotation of the second wheel 9. Generally, when the wheels of the vehicle require a greater torque output, the first drive assembly and the second drive assembly are required to provide greater torque to the first wheel 8 and the second wheel 9.

[0040] Specifically, the driving source 51 can be a power-assisting motor. For example, the power-assisting motor is selectively connected to the first drive assembly through the first transmission assembly, and can also be selectively connected to the second drive assembly through the second transmission assembly, so that the power-assisting mechanism 5 and the first drive assembly can jointly output torque to the first wheel 8, and the power-assisting mechanism 5 and the second drive assembly 53 can jointly output torque to the second wheel 9; in actual application, the power-assisting motor can also be connected to the first drive assembly and disconnected from the second drive assembly. At this time, the power-assisting mechanism 5 can provide power to the first wheel 8 of the vehicle, and the second wheel 9 still maintains the output torque through the second drive assembly, that is, the first wheel 8 can obtain a larger torque.

[0041] Of course, the power-assisting mechanism 5 can also be connected to the power of the second drive assembly and disconnected from the power of the first drive assembly. At this time, the power-assisting mechanism 5 can provide power to the second wheel 9 of the vehicle, and the first wheel 8 still maintains the output torque through the first drive assembly, that is, the second wheel 9 can obtain greater torque.

[0042] Through the setting of the above-mentioned power-assisting mechanism 5, different torques can be output to the first wheel 8 and the second wheel 9 according to different application scenarios and the torque requirements of the vehicle, so as to provide power assistance according to actual needs; for example, when the first wheel 8 and the second wheel 9 need to increase the torque output in the scenario of turning around on the spot or getting out of trouble at low speed, and the power can be output in opposite directions toward the first wheel 8 and the second wheel 9, the power-assisting mechanism 5 can simultaneously realize the increase of the common torque of the two wheels, reduce the torque requirements of the first drive component and the second drive component, thereby reducing the volume, weight and cost.

[0043] In some embodiments, the speed ratio between the driving source 51 and the first wheel 8 is a, and the speed ratio between the driving source 51 and the second wheel 9 is b, and a>100, b>100 is satisfied.

[0044] That is to say, the speed ratio from the drive source 51 to the wheel end can be designed to be above 100. For example, it can be designed to be 150 in practice. Then, the speed ratio from the input end of the first drive assembly to the first wheel 8 can be 10, and the speed ratio from the drive source 51 to the input end of the first drive assembly can be 15. When the drive source 51 provides 10 Nm of assist torque, an output torque of about 1500 Nm (10*10*15) will be generated to the first wheel 8, which is equivalent to reducing the burden of the first drive assembly by 150 Nm (1500 / 10), which is a great contribution. Similarly, the speed ratio from the input end of the second drive assembly to the second wheel 9 can be 10. Assuming that the speed ratio from the drive source 51 to the input end of the second drive assembly can be 16, when the drive source 51 provides 10 Nm of assist torque, an output torque of about 1600 Nm (10*10*16) will be generated to the second wheel 9, which is equivalent to reducing the burden of the second drive assembly by 160 Nm (1600 / 10), which is a great contribution. In this way, the torque requirements of the first drive assembly and the second drive assembly can be reduced, and a higher torque can be output to the first wheel 8 and the second wheel 9 with the help of the drive source 51 of the power assist mechanism 5 .

[0045] In some embodiments, the speed ratio of the driving source 51 to the first wheel 8 is a, the speed ratio of the driving source 51 to the second wheel 9 is b, and the following conditions are satisfied: a=b.

[0046] At this time, the speed ratio output by the driving source 51 to the first wheel 8 and the second wheel 9 is the same. For example, if the speed ratio from the driving source 51 to the first wheel 8 is 150, then the speed ratio from the driving source 51 to the second wheel 9 can also be 150. This can simultaneously enhance the torque of the first wheel 8 and the second wheel 9 on both sides, thereby improving the smoothness of the torque output.

[0047] In some embodiments, the first drive assembly includes a first motor 1 and a first reducer 3, and the first transmission assembly and the first motor 1 are suitable for jointly transmitting power to the first reducer 3, and transmitting the power to the first wheel 8 through the first reducer 3; the second drive assembly includes a power-connected second motor 2 and a second reducer 4, and the second transmission assembly and the second motor 2 are suitable for jointly transmitting power to the second reducer 4, and transmitting the power to the second wheel 9 through the second reducer 4.

[0048] Among them, when the power-assisting mechanism 5 is not working, the power is transmitted to the first reduction mechanism 3 through the first motor 1, and then to the first wheel 8 through the first reduction mechanism 3. The second motor 2 transmits the power to the second reduction mechanism 4, and then to the second wheel 9 through the second reduction mechanism 4.

[0049] When the power-assisting mechanism 5 is working, the power-assisting motor outputs the amplified torque to the first reducer 3 through the first transmission assembly. Figure 2 In the embodiment, the first reducer 3 includes a first output gear 31, a second output gear 32, a third output gear 33 and a fourth output gear 34. The first motor 1 can output power to the first output gear 31. The first output gear 31 is engaged with the second output gear 32. The second output gear 32 and the third output gear 33 are fixedly connected and coaxial. The third output gear 33 and the fourth output gear 34 are engaged, and the fourth output gear 34 outputs power to the first wheel 8, so that the first reduction mechanism 3 further amplifies the torque to the first wheel 8; and the power assist mechanism 5 is amplified by the second transmission assembly. The amplified torque is input to the second reducer 4, which includes a fifth output gear 41, a sixth output gear 42, a seventh output gear 43, and an eighth output gear 44. The second motor 2 can output power to the fifth output gear 41. The fifth output gear 41 meshes with the sixth output gear 42. The sixth output gear 42 and the seventh output gear 43 are fixedly connected and coaxial. The seventh output gear 43 meshes with the eighth output gear 44. The eighth output gear 44 outputs power to the second wheel 9. In other words, the torque is further amplified to the second wheel 9 by the second reduction mechanism 4. In this way, the power-assisting motor and the first reducer 3 jointly output power to the first wheel 8, and the second reducer 4 jointly output power to the second wheel 9. Therefore, not only can the transmission ratio of the power-assisting motor be designed to be larger, but the output torque of the power-assisting motor itself and the output torque of the first drive assembly and the second drive assembly can also be designed to be smaller, while achieving a larger torque transmission to the first wheel 8 and the second wheel 9.

[0050] In some embodiments, when the vehicle is in a driving condition, the speed range of the first motor 1 is controlled to be in a high-efficiency operating area, and / or the speed range of the second motor 2 is controlled to be in a high-efficiency operating area.

[0051] In other words, the speed ranges of first motor 1 and second motor 2 can be controlled to be within the high-efficiency operating range, or one of first motor 1 and second motor 2 can be controlled to be within the high-efficiency operating range. The high-efficiency operating range is the speed range where the ratio of motor output power to input power is the highest, reflecting the motor's ability to convert electrical energy into mechanical energy, thereby improving motor utilization. For example, the motor's highest operating efficiency is within the range of 80% to 100% of the rated speed, which is called the motor's high-efficiency speed range. Within this range, the motor's power loss is minimized, and energy consumption is correspondingly reduced.

[0052] That is, by controlling the first motor 1 and the second motor 2 to be in a high-efficiency operating area when the vehicle is traveling, the utilization rate of the first motor 1 and the second motor 2 can be improved, so that the power loss is low while outputting the same power.

[0053] In some embodiments, when the vehicle is in a U-turn condition, the drive source 51 is controlled to output a first maximum torque, and the first motor 1 is controlled to output a first residual torque, wherein the speed ratio of the drive source 51 output to the first wheel 8 is a first speed ratio, and the speed ratio of the first motor 1 output to the first wheel 8 is a second speed ratio, and the first residual torque = (U-turn torque requirement - first maximum torque * first speed ratio) / second speed ratio.

[0054] When the vehicle is making a U-turn on the spot, if the turning torque requirement for the first wheel 8 is high, the drive source 51 outputs the first maximum torque and the first motor 1 outputs the first residual torque to jointly output power to the first wheel 8. The first residual torque multiplied by the corresponding second speed ratio and the first maximum torque multiplied by the corresponding first speed ratio jointly output the turning torque, which is the required turning torque requirement. This means that the first motor 1 and the drive source 51 jointly output power to the first wheel 8. Therefore, when the required turning torque is constant, the torque of the first motor 1 and the torque of the drive source 51 can be appropriately adjusted to meet the turning torque requirement for the first wheel 8. The first residual torque can be derived from data such as the turning torque requirement, the first maximum torque, the first speed ratio, and the second speed ratio.

[0055] In some embodiments, when the vehicle is in a U-turn condition, the drive source 51 is controlled to output the second maximum torque, and the second motor 2 is controlled to output the second residual torque, wherein the speed ratio of the drive source 51 output to the second wheel 9 is the third speed ratio, and the speed ratio of the second motor 2 output to the second wheel 9 is the fourth speed ratio, and the second residual torque = (U-turn torque requirement - second maximum torque * third speed ratio) / fourth speed ratio.

[0056] In practice, the second wheel 9 and the first wheel 8 are located on opposite sides. When the drive source 5 does not output power to the left first drive assembly, for example, when a greater U-turn torque is required for the second wheel 9, when power is transmitted between the drive source 51 and the right second drive assembly and the drive source 51 outputs the second maximum torque, the second motor 2 outputs a second residual torque. The second residual torque multiplied by the corresponding fourth speed ratio and the second maximum torque multiplied by the corresponding third speed ratio jointly output the U-turn torque, i.e., the required U-turn torque requirement, thereby enabling the second motor 2 and the drive source 51 to jointly output power to the second wheel 9. When the required U-turn torque is constant, the torque of the second motor 2 and the torque of the drive source 51 can be appropriately adjusted to meet the U-turn torque requirement of the second wheel 9. In other words, the second residual torque can be derived from data such as the U-turn torque requirement, the second maximum torque, the third speed ratio, and the fourth speed ratio.

[0057] In some embodiments, the first motor 1 is provided with a first output shaft, the second motor 2 is provided with a second output shaft, the first output shaft and the wheel shaft 10 of the vehicle are coaxially distributed, and the second output shaft and the wheel shaft 10 of the vehicle are coaxially distributed.

[0058] Reference Figure 4 and Figure 5 As shown, the first output shaft is coaxial with the wheel shaft 10 corresponding to the first wheel 8, and the second output shaft is coaxial with the wheel shaft 10 corresponding to the second wheel 9. At the same time, the space occupied by the power assist mechanism 5 in the height direction of the vehicle can be saved, and the integration degree of the middle position between the first wheel 8 and the second wheel 9 of the vehicle is higher.

[0059] When the first output shaft and the second output shaft are coaxial with the wheel shaft 10, the structures of the corresponding first reduction mechanism 3 and the second reduction mechanism 4 are changed, such as Figure 4 In the figure, the first reduction mechanism 3 includes a first sun gear 35, a first planetary gear 36, a first planetary ring gear 37 and a first planetary carrier 38. The first output shaft of the first motor 1 transmits power to the first sun gear 35, the first sun gear 35 drives the first planetary gear 36 to rotate, the first planetary ring gear 37 is fixed, the first planetary gear 36 drives the first planetary carrier 38 to rotate, so that the first planetary carrier 38 drives the first wheel 8 to rotate; similarly, the second reduction mechanism 4 includes a second sun gear 45, a second planetary gear 46, a second planetary ring gear 47 and a second planetary carrier 48. The second output shaft of the second motor 2 transmits power to the second sun gear 45, the second sun gear 45 drives the second planetary gear 46 to rotate, the second planetary ring gear 47 is fixed, the second planetary gear 46 drives the second planetary carrier 48 to rotate, so that the second planetary carrier 48 drives the second wheel 9 to rotate; in this way, the output end of the power assist mechanism 5 can be more integrated with the output end of the first motor 1, the output end of the second motor 2 and the wheel shaft 10, saving the height or longitudinal space of the vehicle.

[0060] Furthermore, Figure 5 and Figure 4 The difference is that Figure 5 The first planetary gears 36 are provided in two groups, and the two groups of first planetary gears 36 are axially spaced apart. The second planetary gears 46 are provided in two groups, and the two groups of second planetary gears 46 are axially spaced apart. This makes the position setting of the first sun gear 35 and the second sun gear 45 more flexible. In addition, it can also make the force transmitted to the first planet carrier 38 and the second planet carrier 48 more uniform and more stable, that is, more stable when transmitted to the first wheel 8 or the second wheel 9.

[0061] In some embodiments, the first motor 1 is provided with a first output shaft, the second motor 2 is provided with a second output shaft, the first output shaft and the wheel shaft 10 of the vehicle are parallel and spaced apart, and the second output shaft and the wheel shaft 10 of the vehicle are parallel and spaced apart.

[0062] That is Figure 1-Figure 3 In the case where the first output shaft and the second output shaft are axially opposed to each other in the width direction of the vehicle, and the wheel axle 10 is arranged parallel to and spaced apart from the first output shaft and the second output shaft, space can be reserved in the middle between the first wheel 8 and the second wheel 9 to facilitate the layout of other structures. The layout is more flexible, making the structural design of the first reduction mechanism 3 and the second reduction mechanism 4 more flexible.

[0063] In some embodiments, the output end of the power-assisting mechanism 5 is selectively connected to the first reduction mechanism 3 and / or the second reduction mechanism 4 to selectively transmit power to the first wheel 8 and / or the second wheel 9 .

[0064] Reference Figure 1 As shown, the output end of the power assist mechanism 5 includes a first transmission assembly, which is selectively engaged with the first reduction mechanism 3. The first motor 1 is power-connected to the first reduction mechanism 3, so that the first motor 1 and the power assist mechanism 5 can jointly output torque to the first wheel 8 through the first reduction mechanism 3, thereby increasing the output torque of the first wheel 8.

[0065] The output end of the power assist mechanism 5 also includes a second transmission assembly, which is selectively engaged with the second reduction mechanism 4. The second motor 2 is power-connected to the second reduction mechanism 4, so that the second motor 2 and the power assist mechanism 5 can jointly output power to the second wheel 9 through the second reduction mechanism 4, thereby increasing the output torque of the second wheel 9.

[0066] That is Figure 1 and Figure 2It represents a first embodiment. The power-assisting mechanism 5 in the first embodiment is suitable for being dynamically connected with the first reduction mechanism 3 and the second reduction mechanism 4, so that the first reduction mechanism 3 and the second reduction mechanism 4 are closer to the middle position between the first wheel 8 and the second wheel 9, and transmit torque to the first wheel 8 and / or the second wheel 9 at a position closer to the output ends of the first motor 1 and the second motor 2, so that the torque output by the first motor 1 and the power-assisting mechanism 5 can act on the first wheel 8 faster, and the torque output by the second motor 2 and the power-assisting mechanism 5 can act on the second wheel 9 faster.

[0067] In some embodiments, the output end of the power-assisting mechanism 5 is selectively connected to the first motor 1 and / or the second motor 2 to selectively transmit power to the first wheel 8 and / or the second wheel 9 .

[0068] Reference Figure 3 、 Figure 4 and Figure 5 As shown, the power-assisting mechanism 5 is selectively connected to the first motor 1 and selectively connected to the second motor 2. That is, the power-assisting mechanism 5 outputs power to the input end of the first motor 1 and the input end of the second motor 2. When the first motor 1 transmits power to the first wheel 8 through the first reduction mechanism 3, the power of the power-assisting mechanism 5 combines with the power of the first motor 1 to output torque to the first wheel 8; and when the second motor 2 transmits power to the second wheel 9 through the second reduction mechanism 4, the power of the power-assisting mechanism 5 combines with the power of the second motor 2 to output torque to the second wheel 9. In other words, under the premise that the power-assisting mechanism 5 can provide power, the power-assisting mechanism 5 and the first drive assembly and the second drive assembly can be flexibly arranged and connected according to actual needs.

[0069] In some embodiments, the first transmission assembly includes a first gear pair 52 and a first coupling-disconnection device 6, the driving source 51 outputs power to the first gear pair 52, and the first gear pair 52 is selectively connected to the first drive assembly through the first coupling-disconnection device 6; the second transmission assembly includes a second gear pair 53 and a second coupling-disconnection device 7, the driving source 51 outputs power to the second gear pair 53, and the second gear pair 53 is selectively connected to the second drive assembly through the second coupling-disconnection device 7.

[0070] In practice, the first transmission assembly includes a first power-assisting gear 521, a second power-assisting gear 522, and a first coupling-disconnection device 6. The first power-assisting gear 521 is power-connected to the output end of the power-assisting motor, and the second power-assisting gear 522 is meshed with the first power-assisting gear 521. The second power-assisting gear 522 can be selectively connected to or disconnected from the first drive assembly via the first coupling-disconnection device 6. The first transmission assembly includes a third power-assisting gear 531, a fourth power-assisting gear 532, and a fifth power-assisting gear 533. The third power-assisting gear 531 is power-connected to the output end of the power-assisting motor, the fourth power-assisting gear 532 is meshed with the third power-assisting gear 531, and the fifth power-assisting gear 533 is meshed with the fourth power-assisting gear 532. The fifth power-assisting gear 533 can be selectively connected to or disconnected from the second drive assembly via the second coupling-disconnection device 7. In other words, the first coupling-disconnection device 6 and the second coupling-disconnection device 7 can be clutches, which, as selectively connected components, can be connected or disconnected according to actual needs.

[0071] In some embodiments, the power drive system 100 includes: when the first wheel 8 is suspended or has insufficient adhesion and the second wheel 9 can travel normally, the first coupling disconnection device 6 is controlled to be in a disconnected state, and the second coupling disconnection device 7 is controlled to be in a coupled state, and the power of the power assist mechanism 5 and the second drive assembly is jointly transmitted to the second wheel 9; that is, when the vehicle falls into a puddle or an uneven road section, the second wheel 9 of the vehicle touches the ground, and the first wheel 8 of the vehicle is suspended and has insufficient adhesion. If power is output to the first wheel 8, the first wheel 8 will idle ineffectively. At this time, when the power assist mechanism 5 outputs power, it can mainly output power to the second wheel 9, saving power and reducing power loss.

[0072] Similarly, when the second wheel 9 is suspended or has insufficient adhesion and the first wheel 8 can travel normally, the first coupling disconnection device 6 is controlled to be in a coupled state, and the second coupling disconnection device 7 is controlled to be in a disconnected state, and the power of the power assist mechanism 5 and the first drive assembly is transmitted to the first wheel 8 together; at this time, since the second wheel 9 is suspended, if power is output to the second wheel 9, the second wheel 9 will idle ineffectively. At this time, the second coupling disconnection device 7 can be disconnected, and the drive source 51 does not output power to the second wheel 9, and the power is mainly output to the first wheel 8, thereby reducing power loss.

[0073] In addition, when the first wheel 8 and the second wheel 9 are both on the ground but lack power, the first coupling disconnection device 6 is controlled to be in a coupled state, and the second coupling disconnection device 7 is controlled to be in a coupled state, and the power of the power assist mechanism 5 and the first drive assembly is jointly output to the first wheel 8, and the power of the power assist mechanism 5 and the second drive assembly is jointly output to the second wheel 9.

[0074] At this time, the first wheel 8 and the second wheel 9 can travel normally, but due to insufficient power, they can be assisted by the power source 51, that is, the power output of the first drive component to the first wheel 8 is insufficient and the power output of the second drive component to the second wheel 9 is insufficient. Then, by setting the power source 51, and the power source 51 can output power to the first wheel 8 and the second wheel 9, thereby achieving the enhancement of the power of the first wheel 8 and the second wheel 9, a power-assisted motor with smaller torque and power can be used to greatly reduce the torque demand for the first motor 1 and the second motor 2, thereby reducing the overall volume, weight and cost.

[0075] In addition, when the vehicle makes a U-turn on the spot, the torque demand for the first and second drive components for the U-turn function is far greater than the torque demand for the first and second drive components due to power performance, and the left and right wheels are in a state where the torque and speed directions are one positive and one negative. Taking a right turn as an example, the front left wheel and the rear left wheel rotate forward, while the front right wheel and the rear right wheel rotate backward. In other words, the torque distribution for a left turn on the spot is opposite to that for a right turn on the spot. Under the traditional distributed electric drive design method, if the vehicle is to meet the full-load high-attachment VOT (U-turn on the spot) requirement, the high-attachment VOT requirement can be understood as the higher torque requirement required for the vehicle to make a U-turn on the spot. Therefore, the torque requirements output by the first and second drive components must be designed according to the maximum VOT requirement.

[0076] By connecting the power-assisting mechanism 5 to the first drive assembly and the second drive assembly, one transmission path is connected to the first drive assembly through the first coupling disconnecting device 6, and the other transmission path is connected to the second drive assembly through the second coupling disconnecting device 7, and the two transmission paths are in opposite directions; then, when the VOT working condition is started, one of the first wheel 8 and the second wheel 9 rotates forward, and the other wheel rotates reversely. Therefore, such a design enables the power-assisting mechanism 5 to transmit part of the torque in the forward direction to the first wheel 8 on one side, and transmit the other part of the torque in the reverse direction to the second wheel 9 when working. Therefore, the torque of the first wheel 8 and the second wheel 9 can be enhanced at the same time to meet the functional requirements of VOT and realize the power requirements of the vehicle turning around in place.

[0077] Under normal vehicle operation, the first disconnecting device 6 is disconnected from the first motor 1, and the second disconnecting device 7 is disconnected from the second motor 2. The power assist mechanism 5 is inoperative, and the first and second drive assemblies operate independently, thereby achieving various independent drive functions. When a pivot point turn is required, either the first disconnecting device 6 or the second disconnecting device 7 is engaged, or both are engaged, depending on the direction of the pivot point turn. This activates the power assist mechanism 5.

[0078] In addition, when low-speed escape is required, the power-assisting mechanism 5 is selectively engaged with the first drive assembly through the first coupling disconnection device 6, or the power-assisting mechanism 5 is selectively engaged with the second drive assembly through the second coupling disconnection device 7, or the power-assisting mechanism 5 is simultaneously engaged with the first drive assembly and the second drive assembly through the first coupling disconnection device 6 and the second coupling disconnection device 7, and the power-assisting mechanism 5 starts to work, achieving a larger torque output, thereby achieving low-speed escape.

[0079] The embodiment of the present invention further proposes a four-drive power system, including two sets of the above-mentioned power drive systems, wherein one set of power drive systems 100 is located at the front of the vehicle, and the other set of power drive systems 100 is located at the rear of the vehicle.

[0080] In practice, when a four-wheel independent drive vehicle performs functions such as turning around on the spot or making a compass turn under high adhesion, full load, and low steady speed, very high requirements are placed on the peak torque and duration of the first motor 1 and the second motor 2, resulting in a significant increase in the volume, weight, and cost of the first motor 1 and the second motor 2, and may even lead to the problem of being unable to be arranged in a limited space.

[0081] Then each of the four wheels of the vehicle is equipped with a motor, and when the first wheel 8 and the second wheel 9 on the front side are underpowered, the first wheel 8 or the second wheel 9 can be assisted by the driving source 5; similarly, when the first wheel 8 and the second wheel 9 on the rear side are underpowered, the first wheel 8 and the second wheel 9 can also be assisted by the driving source 5, and when the power output by the first motor 1 or the second motor 2 meets the current power, the driving source 5 can selectively disconnect the power transmission between any one of the wheels; in this way, power assistance or non-assistance can be achieved according to the different power requirements of the four wheels of the vehicle, which is more flexible and can also reduce the requirements for the peak torque and duration of the first motor 1 and the second motor 2, and reduce the volume and weight of the first motor 1 and the second motor 2.

[0082] In some embodiments, the driving source 51 of each power drive system 100 is connected to the first drive component through a first transmission component, and is connected to the second drive component through a second transmission component. The first drive component located on one side of the vehicle drives the first wheel 8 to rotate in a first direction, and the second drive component located on the other side of the vehicle drives the second wheel 9 to rotate in a second direction.

[0083] In practice, when a vehicle makes a U-turn on the spot, it rotates around the vehicle's center of mass by making the wheels on the left and right sides of the vehicle rotate in opposite directions, thereby generating a rotational movement around the vehicle's center of mass, allowing the vehicle to turn on the spot. The realization of a U-turn on the spot depends on the independent control of four motors. By applying driving torques in opposite directions to the wheels on the left and right sides of the vehicle, the tires will break through the limitations of road adhesion and generate rotation around the vehicle's center of mass, thereby achieving a U-turn on the spot.

[0084] If the vehicle needs to turn right and make a U-turn on the spot, the left wheel of the vehicle, that is, the first wheel 8, rotates toward the front, and the right wheel, that is, the second wheel 9, rotates toward the rear. Looking from the left side of the vehicle, the left wheel, that is, the first wheel 8, rotates counterclockwise, and the second wheel 9 rotates clockwise. When the vehicle is driving, it mainly relies on the front wheels to change the direction of travel, and the rear wheels play a stabilizing and supporting role. However, to make a U-turn on the spot, all four wheels must be able to rotate, that is, the first wheel 8 of the rear wheel also rotates forward, and the second wheel 9 of the rear wheel rotates backward, thereby making a U-turn on the spot. When the vehicle makes a U-turn on the spot, the power requirements of the four wheels are different. Therefore, one drive source 51 can be used to provide power to the first wheel 8 and / or the second wheel 9 on the front side, and another drive source 51 can be used to provide power to the first wheel 8 and / or the second wheel 9 on the rear side.

[0085] In some embodiments, the driving source 51 of one group of power drive systems 100 disconnects power transmission from the first wheel 8 and transmits power to the second wheel 9, and the driving source 51 of another group of power drive systems 100 transmits power to both the first wheel 8 and the second wheel 9 at the same time.

[0086] In practice, the compass turn technology enables the vehicle to complete a U-turn in an extremely narrow space, such as at the entrance of a residential area, the entrance of a shopping mall, etc., which can easily complete a U-turn. This is very useful for driving in an urban environment, especially in places with limited space, and can significantly improve the convenience and flexibility of driving. When the vehicle is performing a compass turn, any one of the four wheels of the vehicle can be fixed, such as fixing one of the first wheels 8 on the front side, and then disconnecting the drive source 51 from the first coupling disconnecting device 6. The drive source 51 no longer drives one of the first wheels 8 to rotate. The power outputs of the other three wheels are different, and can be powered by the corresponding first motor 1 in combination with the drive source 51, and at the same time, powered by the corresponding second motor 2 in combination with the drive source 52.

[0087] Therefore, the power assist mechanism 5 of the embodiment of the present invention can play a role in different application scenarios, and can meet different power requirements in scenarios such as turning around on the spot, getting out of trouble at low speed, and making a compass turn. When realizing functions such as turning around on the spot or making a compass turn, the torque requirements of the two coaxially arranged wheels are also different, and according to the actual simulation results, the difference is relatively large. The driving source 52 can realize simultaneous driving and selective driving of the first wheel 8 and the second wheel 9 on both sides. For four-wheel drive, the driving sources 52 on the front and rear sides can ultimately assist one wheel, two wheels, three wheels, or all four wheels at the same time, meeting different application scenarios, with higher flexibility and reducing the power requirements of the first motor 1 and the second motor 2.

[0088] Specifically, it should be noted that the total speed of the power-assisting mechanism 5 to the wheel end is designed to be 150. If the speed ratio of the first motor 1 to the first wheel 8 is 10 at this time, then the speed ratio of the power-assisting motor to the first motor 1 is 15. When the power-assisting motor provides 10Nm of power-assisting torque, then an output torque of about 1500Nm (10*10*15) will be generated at the wheel end, which is equivalent to reducing the burden of the first motor by 150Nm (1500 / 10), which is a huge contribution. At the same time, due to the VOT working condition (in-situ U-turn), the wheel speed is relatively low, and the corresponding first motor is about 100rpm. At this time, the speed of the power-assisting motor is about 1500rpm, so the power of the power-assisting motor is about 1.5kw. It can be seen that using a power-assisting motor with smaller torque and power can greatly reduce the torque demand for the main first motor, thereby reducing the overall volume, weight and cost.

[0089] An embodiment of the present invention also proposes a vehicle, including the above-mentioned power drive system 100, which enhances the torque output of the first wheel 8 and the second wheel 9 by providing a power assist mechanism 5, and reduces the torque demand for the first drive component and the second drive component, thereby reducing the volume, weight and cost of the overall structure. The power assist mechanism 5 outputs opposite power assist torques to the first wheel 8 and the second wheel 9, thereby realizing the high torque demand required by the first wheel 8 and the second wheel 9 when turning around on the spot.

[0090] 1. In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the devices or elements referred to must have a specific direction, be constructed and operate in a specific direction. Therefore, they should not be understood as limiting the present invention.

[0091] 2. In the description of the present invention, "first feature" and "second feature" may include one or more of these features.

[0092] 3. In the description of the present invention, “plurality” means two or more.

[0093] 4. In the description of the present invention, a first feature being “above” or “below” a second feature may include the first and second features being in direct contact, or the first and second features being in contact not directly but via another feature therebetween.

[0094] 5. In the description of the present invention, the phrases “above”, “above” and “above” a first feature to a second feature include the first feature being directly above and obliquely above the second feature, or simply indicate that the first feature is horizontally higher than the second feature.

[0095] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0096] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A power drive system (100), characterized in that: include: a first drive assembly and a second drive assembly, wherein the first drive assembly is connected to a first wheel (8) in power, and the second drive assembly is connected to a second wheel (9) in power, wherein the first wheel (8) and the second wheel (9) are located at the front or rear of the vehicle; A power assist mechanism (5), the power assist mechanism (5) comprising a driving source (51), a first transmission assembly, and a second transmission assembly, the driving source (51) being selectively connected to the first driving assembly via the first transmission assembly, and the driving source (51) being selectively connected to the second driving assembly via the second transmission assembly, wherein the power output directions of the first transmission assembly and the second transmission assembly are different.

2. The power drive system (100) according to claim 1, characterized in that: The speed ratio between the driving source (51) and the first wheel (8) is a, and the speed ratio between the driving source (51) and the second wheel (9) is b, and a>100, b>100 is satisfied.

3. The power drive system (100) according to claim 2, characterized in that: The speed ratio between the driving source (51) and the first wheel (8) is a, and the speed ratio between the driving source (51) and the second wheel (9) is b, and they satisfy: a=b.

4. The power drive system (100) according to claim 1, characterized in that: The first drive assembly comprises a first motor (1) and a first reducer (3), the first transmission assembly and the first motor (1) being adapted to jointly transmit power to the first reducer (3), and the power is transmitted to the first wheel (8) via the first reducer (3); The second drive assembly comprises a second motor (2) and a second reducer (4) connected in power, the second transmission assembly and the second motor (2) are adapted to jointly transmit power to the second reducer (4), and transmit the power to the second wheel (9) via the second reducer (4).

5. The power drive system (100) according to claim 4, characterized in that: When the vehicle is in a driving condition, the speed range of the first motor (1) is controlled to be in a high-efficiency operating area, and / or the speed range of the second motor (2) is controlled to be in a high-efficiency operating area.

6. The power drive system (100) according to claim 4, characterized in that: When the vehicle is in a U-turn condition, the drive source (51) is controlled to output a first maximum torque, and the first motor (1) is controlled to output a first residual torque, wherein the speed ratio of the drive source (51) output to the first wheel (8) is a first speed ratio, the speed ratio of the first motor (1) output to the first wheel (8) is a second speed ratio, and the first residual torque = (U-turn torque requirement - first maximum torque * first speed ratio) / second speed ratio.

7. The power drive system (100) according to claim 4, characterized in that: When the vehicle is in a U-turn condition, the drive source (51) is controlled to output a second maximum torque, and the second motor (2) is controlled to output a second residual torque, wherein the speed ratio of the drive source (51) output to the second wheel (9) is the third speed ratio, the speed ratio of the second motor (1) output to the second wheel (9) is the fourth speed ratio, and the second residual torque = (U-turn torque requirement - second maximum torque * third speed ratio) / fourth speed ratio.

8. The power drive system (100) according to claim 4, characterized in that: The first motor (1) is provided with a first output shaft, the second motor (2) is provided with a second output shaft, the first output shaft and the wheel shaft (10) of the vehicle are coaxially distributed, and the second output shaft and the wheel shaft (10) of the vehicle are coaxially distributed.

9. The power drive system (100) according to claim 4, characterized in that: The first motor (1) is provided with a first output shaft, the second motor (2) is provided with a second output shaft, the first output shaft and the wheel shaft (10) of the vehicle are arranged in parallel and spaced apart, and the second output shaft and the wheel shaft (10) of the vehicle are arranged in parallel and spaced apart.

10. The power drive system (100) according to claim 4, characterized in that: The output end of the power-assisting mechanism (5) is selectively connected to the first reducer (3) and / or the second reducer (4) to selectively transmit power to the first wheel (8) and / or the second wheel (9).

11. The power drive system (100) according to claim 4, characterized in that: The output end of the power-assisting mechanism (5) is selectively connected to the first motor (1) and / or the second motor (2) to selectively transmit power to the first wheel (8) and / or the second wheel (9).

12. The power drive system (100) according to claim 1, characterized in that The first transmission assembly includes a first gear pair (52) and a first coupling and disconnecting device (6), the driving source (51) outputs power to the first gear pair (52), and the first gear pair (52) is selectively connected to the first driving assembly through the first coupling and disconnecting device (6); The second transmission assembly includes a second gear pair (53) and a second coupling and disconnecting device (7), the driving source (51) outputs power to the second gear pair (53), and the second gear pair (53) is selectively connected to the second driving assembly through the second coupling and disconnecting device (7).

13. The power drive system (100) according to claim 12, characterized in that: include: When the first wheel (8) is suspended or has insufficient adhesion and the second wheel (9) can travel normally, the first coupling disconnection device (6) is controlled to be in a disconnected state, and the second coupling disconnection device (7) is controlled to be in a coupled state, and the power of the power assist mechanism and the second drive assembly is transmitted to the second wheel (9) together; When the second wheel (9) is suspended or has insufficient adhesion and the first wheel (8) can travel normally, the first coupling and disconnecting device (6) is controlled to be in a coupled state, and the second coupling and disconnecting device (7) is controlled to be in a disconnected state, and the power of the power assist mechanism and the first drive assembly is transmitted to the first wheel (8) together; When both the first wheel (8) and the second wheel (9) are on the ground but lack power, the first coupling-disconnecting device (6) is controlled to be in a coupled state, and the second coupling-disconnecting device (7) is controlled to be in a coupled state, the power of the power-assisting mechanism and the first drive assembly is jointly output to the first wheel (8), and the power of the power-assisting mechanism (5) and the second drive assembly is jointly output to the second wheel (9).

14. A four-wheel drive power system, characterized in that: It comprises two groups of power drive systems (100) according to any one of claims 1 to 13, wherein one group of the power drive systems (100) is arranged at the front of the vehicle, and the other group of the power drive systems (100) is arranged at the rear of the vehicle.

15. The four-wheel drive system according to claim 14, characterized in that: The driving source (51) of each group of the power drive system (100) is connected to the first drive component through the first transmission component, and is connected to the second drive component through the second transmission component. The first drive component located on one side of the vehicle drives the first wheel (8) to rotate in a first direction, and the second drive component located on the other side of the vehicle drives the second wheel (9) to rotate in a second direction.

16. The four-wheel drive system according to claim 14, characterized in that: The driving source (51) of one group of the power drive systems (100) disconnects power transmission from the first wheel (8) and transmits power to the second wheel (9), while the driving source (51) of the other group of the power drive systems (100) transmits power to both the first wheel (8) and the second wheel (9) at the same time.

17. A vehicle, characterized in that: It comprises the power drive system (100) described in any one of claims 1-13, or the four-drive power system described in any one of claims 14-16.

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