Bridge driving system and vehicle

Abstract

A bridge drive system (EA) includes a first electric machine (EM1), a second electric machine (EM2) and a common transmission. The transmission comprises a first planetary gear mechanism and a second planetary gear mechanism which are independent of each other, the first motor can be in transmission connection with a first half shaft (HS1) of the vehicle through the first planetary gear mechanism, and the second motor can be in transmission connection with a second half shaft (HS2) of the vehicle through the second planetary gear mechanism. The first motor and the second motor can independently drive the first half shaft and the second half shaft respectively. Compared with an existing bridge driving system, the number of additional assemblies and power auxiliary systems can be reduced, the transmission ratio of a torque transmission path can be improved through a structure occupying a small space, and therefore cost is remarkably saved, weight is reduced, and reliability is improved. The utility model further provides a vehicle comprising the bridge driving system.

Description

Technical Field

[0001] The present application relates to the field of vehicles, and more specifically to an electric bridge drive system for a vehicle and a vehicle including the electric bridge drive system. Background Art

[0002] Currently, the electric axle drive system can be used in pure electric vehicles and hybrid vehicles for driving the vehicles.

[0003] Figure 1A and Figure 1B 2 and 3 show the structure of an electric bridge drive system EA0 and the structure of a power system of a vehicle using the electric bridge drive system EA0. Figure 1A As shown, the electric bridge drive system EA0 includes an electric motor EM and a transmission assembled together. In the electric bridge drive system EA0, the electric motor EM is used to transmit torque to the transmission. The electric motor EM includes a rotor and a stator. The input shaft of the transmission is connected to the differential DM via a two-stage gear transmission mechanism, thereby transmitting torque to the two half shafts HS1 and HS2 via the differential DM. Figure 1B As shown, the vehicle includes two Figure 1A The electric axle drive system EA0 is shown in the figure, one of which drives two front wheels FW1 and FW2 via two half-shafts HS1 and HS2, and the other electric axle drive system EA0 drives two rear wheels RW1 and RW2 via two half-shafts HS1 and HS2.

[0004] Thus, the above-mentioned vehicle includes two electric axle drive systems, which respectively have motors EM that independently drive the front wheels FW1, FW2 and the rear wheels RW1, RW2, thereby achieving high torque output to meet the performance requirements of high-performance vehicles (such as acceleration time, etc.). However, in the above-mentioned vehicle, the two electric axle drive systems EA0 are independent of each other and have no common parts, so more additional components (such as housings, connectors, shafts, differentials DM, etc.) and two sets of power auxiliary components (such as mounting systems, drive shafts, etc.) are required, which will lead to increased costs, higher weight and reduced reliability. Utility Model Content

[0005] This application is made in view of the defects in the above-mentioned technology. One object of this application is to provide a new type of electric bridge drive system, which reduces the additional components and power auxiliary components used in the system while maintaining the same power system performance, thereby significantly saving costs, reducing weight and improving reliability. Another object of this application is to provide a vehicle including the above-mentioned electric bridge drive system.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions.

[0007] The present application provides an electric bridge drive system as follows, which includes a first motor, a second motor and a common transmission.

[0008] The transmission includes a first planetary gear mechanism and a second planetary gear mechanism that are independent of each other, the first motor can be drivingly coupled to a first half-shaft of the vehicle via the first planetary gear mechanism, and the second motor can be drivingly coupled to a second half-shaft of the vehicle via the second planetary gear mechanism, so that the first motor and the second motor can drive the first half-shaft and the second half-shaft respectively independently of each other,

[0009] The first half-shaft and the second half-shaft are respectively used for driving connection with the two front wheels of the vehicle; or the first half-shaft and the second half-shaft are respectively used for driving connection with the two rear wheels of the vehicle.

[0010] In an optional solution, along the extending direction of the first semi-shaft, the first motor and the first planetary gear mechanism are staggered; and / or

[0011] Along the extending direction of the second semi-shaft, the second motor and the second planetary gear mechanism are staggered.

[0012] In another optional solution, the transmission further includes a housing and a first intermediate shaft and a second intermediate shaft that are independent of each other.

[0013] The first sun gear of the first planetary gear mechanism is connected to the first intermediate shaft in a torsion-proof manner, the first planetary gear carrier of the first planetary gear mechanism is connected to the first half shaft in a torsion-proof manner, and the first ring gear of the first planetary gear mechanism is fixed to the housing;

[0014] The second sun gear of the second planetary gear mechanism is connected to the second intermediate shaft in a rotationally fixed manner, the second planetary gear carrier of the second planetary gear mechanism is connected to the second half shaft in a rotationally fixed manner, and the second ring gear of the second planetary gear mechanism is fixed to the housing.

[0015] In another optional scheme, the transmission also includes a bearing support frame, a first bearing and a second bearing, the bearing support frame is fixed to the housing and is located inside the housing, the first bearing and the second bearing are installed on the bearing support frame, the first intermediate shaft is supported by the first bearing so as to be able to rotate relative to the housing, and the second intermediate shaft is supported by the second bearing so as to be able to rotate relative to the housing.

[0016] In another optional solution, the bearing support frame is located between the first half shaft and the second half shaft.

[0017] In another optional solution, the shell includes a first shell part and a second shell part, and the first shell part and the second shell part can be detachably fixed to each other.

[0018] In another optional solution, the shell is formed with an oil filling hole, an oil drain hole and a ventilation passage.

[0019] In another optional solution, the transmission further includes a first input shaft and a second input shaft.

[0020] The first input shaft is directly connected to the first motor, and the first input shaft is connected to the first intermediate shaft via a gear transmission mechanism.

[0021] The second input shaft is directly connected to the second motor, and the second input shaft is connected to the second intermediate shaft via a gear transmission mechanism.

[0022] In another optional solution, the transmission is at least partially located between the first motor and the second motor.

[0023] The present application also provides a vehicle as follows, which includes the electric bridge drive system described in any one of the above technical solutions.

[0024] By adopting the above technical solution, the present application provides a novel electric bridge drive system and a vehicle including the electric bridge drive system. The electric bridge drive system includes two motors assembled together and a common transmission for the two motors, one motor is used to drive and connect with one half-shaft via a first planetary gear mechanism in the transmission, and the other motor is used to drive and connect with another half-shaft via a second planetary gear mechanism in the transmission. The two half-shafts are respectively used for the two front wheels of the vehicle or the two rear wheels of the vehicle.

[0025] Thus, firstly, since the two motors share the same transmission, the additional components such as the housing, connectors, shafts, etc. can be simplified; secondly, since the two motors are independently connected to the two half-axles for the front wheels or the rear wheels, the differential can be omitted and the number of power-assisted systems can be reduced; thirdly, the planetary gear mechanism is used to realize torque transmission, which can improve the transmission ratio of the torque transmission path with a structure that occupies less space. Therefore, compared with the vehicle including the electric bridge drive system described in the background technology, the vehicle including the above-mentioned electric bridge drive system (two motors working independently of each other) not only maintains basically the same power system performance, but also significantly saves costs, reduces weight and improves reliability. The same transmission used here can be understood as a transmission placed in the same housing, and in other optional schemes, the two motors and the transmission can also be installed in the same housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1A The diagram is a schematic diagram showing the topological structure of an existing electric bridge drive system.

[0027] Figure 1B It shows that the two Figure 1A Schematic diagram of the power system of a vehicle with an electric bridge drive system.

[0028] Figure 2A Schematic diagram showing the connection structure of an electric bridge drive system according to an embodiment of the present application.

[0029] Figure 2B is shown including a Figure 2A A schematic diagram of the power system of a vehicle with an electric bridge drive system.

[0030] Figure 2C is shown including a Figure 2A Schematic diagram of another vehicle power system with an electric bridge drive system.

[0031] Description of Reference Numerals

[0032] EA0 electric axle drive system EM motor DM differential

[0033] EA electric bridge drive system

[0034] EM1 first motor S11 first input shaft S12 first intermediate shaft G11 first input gear G12 first intermediate gear SG1 first sun gear PG1 first planetary gear R1 first ring gear P1 first planetary gear carrier B1 first bearing

[0035] EM2 second motor S21 second input shaft S22 second intermediate shaft G21 second input gear G22 second intermediate gear SG2 second sun gear PG2 second planetary gear R2 second ring gear P2 second planetary gear carrier B2 second bearing

[0036] H housing H11 first housing part H12 second housing part SP bearing support frame T1 oil filling hole T2 oil drain hole T3 ventilation passage

[0037] FW1 first front wheel FW2 second front wheel RW1 first rear wheel RW2 second rear wheel HS1 first half shaft HS2 second half shaft DETAILED DESCRIPTION

[0038] The exemplary embodiments of the present application are described below with reference to the accompanying drawings. It should be understood that these specific descriptions are only used to teach those skilled in the art how to implement the present application, and are not intended to exhaust all feasible methods of the present application, nor to limit the scope of the present application.

[0039] In the present application, “drive coupling” refers to the connection between two components that can transmit driving torque, including direct or indirect connection between the two components.

[0040] In the present application, "torsion-resistant connection" means that two components are directly connected in a manner that can transmit torque and can rotate together. For example, a gear can be mounted on a shaft through a spline structure so that the gear and the shaft can achieve a torsion-resistant connection.

[0041] In the present application, "axial direction" refers to the axial direction of the input shaft of the transmission, and the input shaft of the transmission, the intermediate shaft and the half shafts of the vehicle are parallel to each other.

[0042] The structure of an electric bridge driving system according to an embodiment of the present application will be described below in conjunction with the accompanying drawings.

[0043] like Figure 2A As shown, the electric bridge drive system EA according to an embodiment of the present application includes a first motor EM1, a second motor EM2 and a common transmission for the two motors EM1 and EM2, which are integrated together. The two motors EM1 and EM2 are installed in the housing H of the transmission. In the structural layout of the entire electric bridge drive system EA, a part of the transmission is axially located between the first motor EM1 and the second motor EM2, so that the overall structure of the entire electric bridge drive system EA is more compact. Specifically, in this embodiment, the housing H of the transmission is composed of a first housing part H11 and a second housing part H12 that are detachably fixed to each other. The first housing part H11 and the second housing part H12 are fixed to each other by connecting members such as bolts.

[0044] In this embodiment, the first motor EM1 and the second motor EM2 each include a stator and a rotor located inside the stator and capable of rotating relative to the stator. The rotor of the first motor EM1 is drivingly coupled to the first input shaft S11 of the transmission, so that the first motor EM1 and the transmission can transmit torque in both directions. The rotor of the second motor EM2 is drivingly coupled to the second input shaft S12 of the transmission, so that the second motor EM2 and the transmission can transmit torque in both directions.

[0045] In this embodiment, if Figure 2AAs shown, the transmission is accommodated and installed in a space surrounded by the first housing part H11 and the second housing part H12. The transmission includes a first input shaft S11, a second input shaft S21, a first intermediate shaft S12, a second intermediate shaft S22, a first planetary gear mechanism, a second planetary gear mechanism, and gears arranged on each shaft. The first input shaft S11 and the second input shaft S21 can be coaxially arranged, the first intermediate shaft S12 and the second intermediate shaft S22 can be coaxially arranged, the first input shaft S11 and the second intermediate shaft S12 are parallel to the first half shaft HS1 of the vehicle, and the second input shaft S21 and the second intermediate shaft S22 are parallel to the second half shaft HS2 of the vehicle. The first input shaft S11 is connected to the first half shaft HS1 through a multi-stage gear transmission mechanism of the transmission, and the second input shaft S21 is connected to the second half shaft HS2 through a multi-stage gear transmission mechanism of the transmission, so that the first motor EM1 and the second motor EM2 can drive the first half shaft HS1 and the second half shaft HS2 independently of each other. The specific structures of the torque transmission path from the first motor EM1 to the first half-shaft HS1 and the specific structures of the torque transmission path from the second motor EM2 to the second half-shaft HS2 are described below.

[0046] In the present embodiment, the rotor of the first motor EM1 is connected to the first input shaft S11 of the transmission in a transmission. The first input shaft S11 is formed as a shaft extending in a straight line along the axial direction. The first input gear G11 is connected to the first input shaft S11 in a torsion-proof manner, so that the first input gear G11 can always rotate with the first input shaft S11. The first input gear G11 is always in meshing with the first intermediate gear G12, thereby forming an externally meshed gear pair. The first intermediate gear G12 is connected to the first intermediate shaft S12 in a torsion-proof manner. The first intermediate shaft S12 is formed as a shaft parallel to the first input shaft S11 and extending in a straight line.

[0047] Further, the first planetary gear mechanism includes a first sun gear SG1, a plurality of first planetary gears PG1, a first planetary gear carrier P1 and a first ring gear R1. The first sun gear SG1 is always in meshing with a plurality of first planetary gears PG1 located radially outside thereof. The plurality of first planetary gears PG1 are always in meshing with the first ring gear R1 located radially outside thereof. The plurality of first planetary gears PG1 are mounted on the first planetary gear carrier P1, and the first planetary gear carrier P1 can rotate around the first sun gear SG1 along with the plurality of first planetary gears PG1. In addition, the first sun gear SG1 is torsionally connected to the first intermediate shaft S12, the first planetary gear carrier P1 is torsionally connected to the first half shaft HS1, and the first ring gear R1 is fixed to the first housing portion H11. In this way, the transmission ratio of the torque transmission path from the first motor EM1 to the first half shaft HS1 can be increased by the first planetary gear mechanism.

[0048] In this embodiment, the rotor of the second motor EM2 is connected to the second input shaft S21 of the transmission. The second input shaft S21 is formed as a shaft extending in a straight line along the axial direction. The second input gear G21 is connected to the second input shaft S21 in a torsion-proof manner, so that the second input gear G21 can always rotate with the second input shaft S21. The second input gear G21 is always in meshing with the second intermediate gear G22, thereby forming an externally meshed gear pair. The second intermediate gear G22 is connected to the second intermediate shaft S22 in a torsion-proof manner. The second intermediate shaft S22 is formed as a shaft parallel to the second input shaft S21 and extending in a straight line.

[0049] Further, the second planetary gear mechanism includes a second sun gear SG2, a plurality of second planetary gears PG2, a second planetary gear carrier P2 and a second ring gear R2. The second sun gear SG2 is always in meshing with a plurality of second planetary gears PG2 located radially outside thereof. The plurality of second planetary gears PG2 are always in meshing with the second ring gear R2 located radially outside thereof. The plurality of second planetary gears PG2 are mounted on the second planetary gear carrier P2, and the second planetary gear carrier P2 can rotate around the second sun gear SG2 along with the plurality of second planetary gears PG2. In addition, the second sun gear SG2 is torsionally connected to the second intermediate shaft S22, the second planetary gear carrier P2 is torsionally connected to the second half shaft HS2, and the second ring gear R2 is fixed to the second housing portion H12. In this way, the transmission ratio of the torque transmission path from the second motor EM2 to the second half shaft HS2 can be increased by the second planetary gear mechanism.

[0050] Therefore, the torque transmission path from the first motor EM1 to the first half-shaft HS1 is as follows: first motor EM1→first input shaft S11→first input gear G11→first intermediate gear G12→first intermediate shaft S12→first sun gear SG1→first planetary gear PG1→first planetary gear carrier P1→first half-shaft HS1; the torque transmission path from the second motor EM2 to the second half-shaft HS2 is as follows: second motor EM2→second input shaft S21→second input gear G21→second intermediate gear G22→second intermediate shaft S22→second sun gear SG2→second planetary gear PG2→second planetary gear carrier P2→second half-shaft HS2.

[0051] In order to support the first intermediate shaft S12 and the second intermediate shaft S22 in a manner that they can rotate relative to the housing H, a first bearing B1, a second bearing B2 and a bearing support frame SP are provided. The bearing support frame SP can be fixed to the first housing portion H11 or to the second housing portion H12, and the bearing support frame SP and the first bearing B1 and the second bearing B2 are all located in the space surrounded by the first housing portion H11 and the second housing portion H12. The bearing support frame SP is located between the first half shaft HS1 and the second half shaft HS2, and the first bearing B1 and the second bearing B2 are both installed on the bearing support frame SP and are respectively mounted on the first intermediate shaft S12 and the second intermediate shaft S22. As a result, the first intermediate shaft S12 is supported by the first bearing B1, and the second intermediate shaft S22 is supported by the second bearing B2.

[0052] For the transmission shared by the first motor EM1 and the second motor EM2, an oil filling hole T1 and an oil drain hole T2 may be formed at the bottom of the first housing portion H1, and a ventilation passage T3 may be formed at the top of the second housing portion H2. Thus, lubricating oil can be injected into the housing H through the oil filling hole T1, lubricating oil can be drained from the housing H through the oil drain hole T2, and the transmission can be connected to the inside and outside through the ventilation passage T3.

[0053] Two examples of a power system of a vehicle including the above-described electric axle drive system EA are described below.

[0054] like Figure 2B As shown, the power system of the vehicle may include an electric bridge drive system EA having the above structure, wherein the first motor EM1 of the electric bridge drive system EA is connected to the first half shaft HS1 via a multi-stage gear transmission mechanism (including a first planetary gear mechanism) of a transmission, and the second motor EM2 of the electric bridge drive system EA is connected to the second half shaft HS2 via a multi-stage gear transmission mechanism (including a second planetary gear mechanism) of the transmission. In the vehicle, the first half shaft HS1 is connected to the first front wheel FW1 of the vehicle, and the second half shaft HS2 is connected to the second front wheel FW2 of the vehicle. In this way, the first motor EM1 can independently drive the first front wheel FW1, and the second motor EM2 can independently drive the second front wheel FW2.

[0055] like Figure 2CAs shown, the power system of the vehicle may include an electric bridge drive system EA having the above structure, wherein the first motor EM1 of the electric bridge drive system EA is connected to the first half shaft HS1 via a multi-stage gear transmission mechanism (including a first planetary gear mechanism) of a transmission, and the second motor EM2 of the electric bridge drive system EA is connected to the second half shaft HS2 via a multi-stage gear transmission mechanism (including a second planetary gear mechanism) of the transmission. In the vehicle, the first half shaft HS1 is connected to the first rear wheel RW1 of the vehicle, and the second half shaft HS2 is connected to the second rear wheel RW2 of the vehicle. In this way, the first motor EM1 can independently drive the first rear wheel RW1, and the second motor EM2 can independently drive the second rear wheel RW2.

[0056] In the above Figure 2B and Figure 2C In the vehicles shown, since an electric bridge drive system according to an embodiment of the present application is adopted, compared with the power system of the vehicle described in the background art, the structure is simplified, the weight is reduced, and the cost is saved while basically maintaining the performance.

[0057] Although the technical solution of the present application has been described in detail in the above specific embodiments, the following contents still need to be explained.

[0058] i. Although it is not explicitly described in the above specific embodiments, it should be understood that in the above embodiments, in addition to outputting torque for driving to the transmission, the first motor EM1 and the second motor EM2 can also receive torque from the transmission for charging the battery. In addition, in the above embodiments, the transmission ratio of the torque transmission path from the first motor EM1 to the first half shaft HS1 and the transmission ratio of the torque transmission path from the second motor EM2 to the second half shaft HS2 can be set to be the same.

[0059] ii. The input shafts S11 and S12 of the transmission can be directly used as the motor output shafts of the motors EM1 and EM2, or a motor output shaft independent of the input shafts S11 and S21 can be set, and then the motor output shaft and the input shaft are rigidly connected together by, for example, a coupling.

[0060] iii. In the above specific embodiments, when viewed along the axial direction, the planetary gear mechanism is completely staggered with the motors EM1 and EM2. Specifically, the input shaft is coaxially arranged with the motors EM1 and EM2, and the intermediate shaft is coaxially arranged with the motors EM1 and EM2, so that the planetary gear mechanism is staggered with the motors EM1 and EM2 in a non-coaxial manner, which can help to further reduce the axial size of the entire electric bridge drive system. In addition, when viewed along the height direction of the vehicle, the first motor EM1 and the first planetary gear mechanism can be overlapped, and the second motor EM2 and the second planetary gear mechanism can be overlapped, which can help to further reduce the size of the entire electric bridge drive system.

[0061] iv. The electric bridge drive system EA according to the present application can be applied to pure electric vehicles or hybrid vehicles. In the case where a vehicle has multiple pairs of wheels, the vehicle can include an electric bridge drive system EA that matches the number of wheel pairs.

[0062] v. The present application integrates two motors and a common transmission, which greatly improves the integration of the entire electric bridge drive system. The structure used to realize the torque transmission path of the two motors and the two half-axles can share many components, thereby saving system cost and reducing system weight, and also improving system reliability. By adopting the transmission structure in the above specific embodiment, a larger transmission ratio and a higher power density can be achieved while occupying a smaller space. In addition, by providing torque to a corresponding wheel through one motor, torque vector control of the corresponding wheel can be achieved.

Claims

1. A bridge drive system, characterized in that: The invention comprises a first electric machine (EM1), a second electric machine (EM2) and a common transmission, The transmission comprises a first planetary gear mechanism and a second planetary gear mechanism which are independent of each other, the first motor (EM1) can be drivingly coupled to a first half shaft (HS1) of a vehicle via the first planetary gear mechanism, and the second motor (EM2) can be drivingly coupled to a second half shaft (HS2) of the vehicle via the second planetary gear mechanism, so that the first motor (EM1) and the second motor (EM2) can drive the first half shaft (HS1) and the second half shaft (HS2) respectively independently of each other, The first half shaft (HS1) and the second half shaft (HS2) are respectively used for driving connection with the two front wheels (FW1, FW2) of the vehicle; or the first half shaft (HS1) and the second half shaft (HS2) are respectively used for driving connection with the two rear wheels (RW1, RW2) of the vehicle, The transmission further comprises a housing (H), wherein the housing (H) comprises a first housing portion (H1) and a second housing portion (H2), wherein the first housing portion (H1) and the second housing portion (H2) can be detachably fixed to each other.

2. The electric bridge drive system according to claim 1, characterized in that: Along the direction in which the first half shaft (HS1) extends, the first motor (EM1) and the first planetary gear mechanism are staggered; and / or Along the extending direction of the second half shaft (HS2), the second electric machine (EM2) and the second planetary gear mechanism are arranged staggered.

3. The electric bridge drive system according to claim 2, characterized in that: The transmission further comprises a first intermediate shaft (S12) and a second intermediate shaft (S22) which are independent of each other. The first sun gear (SG1) of the first planetary gear mechanism is connected to the first intermediate shaft (S12) in a torsion-proof manner, the first planetary gear carrier (P1) of the first planetary gear mechanism is connected to the first half shaft (HS1) in a torsion-proof manner, and the first ring gear (R1) of the first planetary gear mechanism is fixed to the housing (H); The second sun gear (SG2) of the second planetary gear mechanism is connected to the second intermediate shaft (S22) in a torsion-proof manner, the second planetary carrier (P2) of the second planetary gear mechanism is connected to the second half shaft (HS2) in a torsion-proof manner, and the second ring gear (R2) of the second planetary gear mechanism is fixed to the housing (H).

4. The electric bridge drive system according to claim 3, characterized in that: The transmission also includes a bearing support frame (SP), a first bearing (B1) and a second bearing (B2), wherein the bearing support frame (SP) is fixed to the housing (H) and is located inside the housing (H), the first bearing (B1) and the second bearing (B2) are installed on the bearing support frame (SP), the first intermediate shaft (S12) is supported by the first bearing (B1) so as to be rotatable relative to the housing (H), and the second intermediate shaft (S22) is supported by the second bearing (B2) so as to be rotatable relative to the housing (H).

5. The electric bridge drive system according to claim 4, characterized in that: The bearing support frame (SP) is located between the first half shaft (HS1) and the second half shaft (HS2).

6. The electric bridge drive system according to claim 1, characterized in that: The housing (H) is formed with an oil filling hole (T1), an oil drain hole (T2) and a ventilation passage (T3).

7. The electric bridge drive system according to any one of claims 3 to 5, characterized in that: The transmission further comprises a first input shaft (S11) and a second input shaft (S21), The first input shaft (S11) is directly connected to the first motor (EM1) through transmission, and the first input shaft (S11) is connected to the first intermediate shaft (S12) through transmission via a gear transmission mechanism. The second input shaft (S21) is directly transmission-connected to the second motor (EM2), and the second input shaft (S21) is transmission-connected to the second intermediate shaft (S22) via a gear transmission mechanism.

8. The electric bridge drive system according to any one of claims 7, characterized in that: The transmission is at least partially located between the first electric machine (EM1) and the second electric machine (EM2).

9. A vehicle, characterized in that: An electric bridge drive system (EA) comprising any one of claims 1 to 8.

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