Dual-motor coaxial electric drive bridge

Abstract

The double-motor coaxial electric drive axle comprises two motors, two groups of planetary gears, a differential and half shafts assembled at left and right ends of the differential, the motors, the planetary gears, the differential and the half shafts are coaxially arranged, characterized in that the two groups of planetary gears are symmetrically arranged at left and right sides of the differential, left and right ends of a differential case of the differential are respectively connected with output ends of the planetary gears through clutches, the output end of one group of planetary gears is assembled with a differential lock assembly capable of locking the differential function of the differential, and the input end of each group of planetary gears is connected with a shaft end of one motor. The double-motor coaxial electric drive axle can reduce the axial size of the electric drive axle, reduce the unsprung mass, be compatible with more application vehicle models, balance the load dynamic distribution of the double motors, reduce the average energy consumption, improve the endurance mileage, improve the passing performance and improve the adaptability of the vehicle to complex road conditions.

Description

Technical Field

[0001] This utility model relates to a dual-motor coaxial electric drive bridge, belonging to the field of pure electric drive bridge technology. Background Technology

[0002] The performance of an electric drive axle is mainly affected by three factors: First, the power transmission path and distribution method of the electric drive axle change with different configurations, thus affecting the output of the electric drive axle; second, the structure of the electric drive axle affects its own mass and volume, thereby affecting its performance; third, the control strategy of the electric drive axle affects the coordinated work of its various components. In a parallel-axis electric drive axle, the motor shaft and half-shaft are parallel, but they are not on the same axis, existing in an offset cantilever state. This results in uneven mass distribution, leading to poor stress and vibration, making the housing more susceptible to damage during operation and affecting the overall vehicle layout. In a coaxial electric drive axle, the motor shaft is a hollow shaft, with the half-shaft passing through the motor rotor and the motor shaft, making the motor shaft and half-shaft on the same axis. Compared to the parallel-axis electric drive axle, the coaxial electric drive axle has advantages such as lower vibration, more uniform mass distribution, and higher stability. However, the coaxial electric drive axle also has the following disadvantages:

[0003] 1. Using a single power source means the vehicle cannot operate if the motor fails, and the power rating is low, which cannot meet the driving requirements under multiple operating conditions. On the other hand, using a coaxial electric drive axle with dual motors cannot balance the dynamic distribution of the load between the two motors, resulting in higher average energy consumption and affecting the driving range.

[0004] 2. The coaxial arrangement increases the axial dimension, resulting in a large unsprung mass and a large axle housing volume, which limits the vehicle model's compatibility and expansion.

[0005] 3. Adaptability to complex road conditions, such as drive slip prevention and vehicle stability control, still needs improvement. Utility Model Content

[0006] The dual-motor coaxial electric drive axle provided by this utility model reduces the axial dimension of the electric drive axle, lowers the unsprung mass, can accommodate more vehicle models, balances the dynamic load distribution of the dual motors, reduces average energy consumption, increases driving range, improves passability, and enhances the vehicle's adaptability to complex road conditions.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0008] A dual-motor coaxial electric drive bridge includes two motors, two sets of planetary gear sets, a differential, and half-shafts mounted on the left and right ends of the differential. The motors, planetary gear sets, differential, and half-shafts are coaxially arranged. The key feature is that the two sets of planetary gear sets are symmetrically arranged on the left and right sides of the differential. The left and right ends of the differential housing are respectively connected to the output ends of the planetary gear sets through clutches. The output ends of one set of planetary gear sets are equipped with differential lock components that can lock the differential function of the differential. The input ends of each set of planetary gear sets are respectively connected to the shaft end of one motor.

[0009] Preferably, the planetary gear set includes a sun gear connected to the motor, a planet carrier, a planetary shaft rotatably mounted on the planet carrier, a first planetary gear coaxially fixed on the planetary shaft and meshing with the sun gear, a gear ring fixed to the bridge housing of the electric drive bridge, and a second planetary gear coaxially fixed on the planetary shaft and meshing with the gear ring. The outer diameter of the first planetary gear is larger than the outer diameter of the second planetary gear. The two planet carriers are respectively connected to the differential housing via clutches.

[0010] Preferably, the output end of the planetary carrier has an integrally formed connecting gear, and the clutch is a clutch sleeve that is slidably mounted on the differential housing along the axial direction. The clutch sleeve is located on the side of the corresponding connecting gear, and the clutch sleeve slides toward the connecting gear to engage with it.

[0011] Preferably, the differential lock assembly includes a locking sleeve that is slidably mounted on the output end of a planetary carrier along the axial direction and a locking gear that is coaxially fixed on the half shaft and corresponds to the locking sleeve. The locking sleeve can slide along the axial direction to engage with the locking gear.

[0012] Preferably, the outer end of the half-shaft passes through the planetary carrier, the sun gear, and the motor, and is connected to the drive wheel.

[0013] The beneficial effects of this utility model are:

[0014] This utility model features a dual-motor coaxial electric drive axle. Two planetary gear sets are symmetrically arranged on the left and right sides of the differential. Each planetary gear set has an input end connected to a motor, forming a symmetrical coaxial structure with the differential as the center. The planetary gear sets, motors, and half-shafts are all symmetrically arranged. The planetary gear sets have a large speed ratio, a compact and stable structure, and reduce the axial dimension of the electric drive axle, thus reducing unsprung mass and accommodating a wider range of vehicle applications. They also effectively reduce motor power and increase torque. The left and right ends of the differential housing are connected to the output ends of the planetary gear sets via clutches, allowing the number of motors involved in the drive to be adjusted according to road conditions. In harsh road conditions, two motors work together to effectively increase wheel-end power density. In smooth road conditions, only one motor is used to drive, effectively improving motor efficiency and reducing energy consumption. This balances the dynamic load distribution of the two motors, reduces average energy consumption, and increases driving range. A differential lock assembly is installed at the output end of one planetary gear set. In slippery road conditions such as sand pits and mud pits, the differential lock assembly locks the differential function, synchronizing the torque of the two half-shafts, improving passability, and enhancing the vehicle's adaptability to complex road conditions. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the transmission structure of the dual-motor coaxial electric drive bridge in a specific implementation.

[0016] Figure 2 for Figure 1 A magnified view of a portion of the image.

[0017] Figure 3 This is a schematic diagram of a planetary array. Detailed Implementation

[0018] The following is combined with Figures 1-3 The embodiments of this utility model will be described in detail below.

[0019] A dual-motor coaxial electric drive bridge includes two motors 1, two sets of planetary gear sets 2, a differential 3, and half-shafts 4 mounted on the left and right ends of the differential 3. The motors 1, planetary gear sets 2, differential 3, and half-shafts 4 are coaxially arranged. The feature is that the two sets of planetary gear sets 2 are symmetrically arranged on the left and right sides of the differential 3. The left and right ends of the differential housing 31 of the differential housing 3 are respectively connected to the output ends of the planetary gear sets 2 through clutches 5. The output ends of one set of planetary gear sets 2 are equipped with differential lock components 6 that can lock the differential function of the differential 3. The input ends of each set of planetary gear sets 2 are respectively connected to the shaft end of one motor 1.

[0020] The dual-motor coaxial electric drive axle described above has two planetary gear sets 2 symmetrically arranged on the left and right sides of the differential 3. Each planetary gear set 2 has its input end connected to a motor 1, forming a symmetrical coaxial structure with the differential 3 as the center. The planetary gear sets 2, motors 1, and half-shafts 4 are all symmetrically arranged on the left and right sides. The planetary gear sets 2 have a large speed ratio, a compact and stable structure, reduce the axial dimension of the electric drive axle, lower the unsprung mass, and can accommodate more vehicle models. It also effectively reduces and increases the torque of the motor power. The left and right ends of the differential housing 31 are connected to the output ends of the planetary gear sets 2 via clutches 5, allowing for adjustments based on the specific requirements of the differential. The number of motors involved in driving is adjusted according to road conditions. In severe road conditions, two motors work together to drive the vehicle, effectively increasing the power density at the wheel ends. In smooth road conditions, only one motor is used to drive the vehicle, effectively improving motor efficiency and reducing energy consumption. This balances the dynamic load distribution of the two motors, reduces average energy consumption, and increases driving range. A differential lock assembly 6 is installed at the output end of a planetary gear set 2. In slippery road conditions such as sand pits and mud pits, the differential lock assembly 6 locks the differential function, synchronizing the torque of the two half-shafts 4, improving passability, and enhancing the vehicle's adaptability to complex road conditions.

[0021] The planetary gear set 2 includes a sun gear 21 connected to the motor, a planet carrier 22, a planet shaft 23 rotatably mounted on the planet carrier 22, a first planet gear 24 coaxially fixed on the planet shaft 23 and meshing with the sun gear 21, a gear ring 25 fixed to the bridge housing of the electric drive bridge, and a second planet gear 26 coaxially fixed on the planet shaft 23 and meshing with the gear ring 25. The outer diameter of the first planet gear 24 is larger than the outer diameter of the second planet gear 26. The two planet carriers 22 are respectively connected to the differential housing 31 through a clutch 5. Motor 1 drives sun gear 21 to rotate, sun gear 21 drives planet gear 24, planet gear 24 drives planet shaft 23 and planet gear 26 to rotate synchronously, planet gear 26 rotates in the gear ring 25, driving planet carrier 22 to rotate, when clutch 5 is engaged, planet carrier 22 transmits power to differential housing 31, causing differential 3 to drive half shaft 4 to move, driving wheel end to move. The use of a compound planetary gear set with two planetary gears can improve the speed ratio and enhance the deceleration and torque increase characteristics, without increasing the axial dimension, ensuring the structural compactness of the electric drive axle.

[0022] The planetary carrier 22 has an integrally formed connecting gear 27 at its output end. The clutch 5 is a clutch sleeve that is axially slidably mounted on the differential housing 31. The clutch sleeve is located on the side of the corresponding connecting gear 27 and slides towards and engages with the connecting gear 27. When the clutch sleeve is not engaged with the connecting gear 37, i.e., when the clutch 5 is disengaged, the power of the planetary carrier 22 cannot be transmitted to the differential housing 31. When the clutch sleeve is engaged with the connecting gear 37, i.e., when the clutch 5 is engaged, the power of the planetary carrier 22 can be transmitted to the differential housing 31. During driving, one or two clutches 5 can be engaged according to the driving requirements to adjust the number of motors involved in the drive. Under smooth road conditions, either motor on the left or right side of the differential 3 can be used for driving, while under harsh conditions, both motors can be used for driving.

[0023] The differential lock assembly 6 includes a locking sleeve 61 slidably mounted on the output end of a planetary carrier 22 along the axial direction and a locking gear 62 coaxially fixed on the half-shaft 4 and corresponding to the locking sleeve 61. The locking sleeve 61 can slide along the axial direction to engage with the locking gear 62. When the locking sleeve 61 and the locking gear 62 are not engaged, the differential 3 has normal differential function. When the vehicle slips, with the corresponding clutch 5 engaged, the locking sleeve 61 is controlled to slide towards the locking gear 62 to engage with it, locking the half-shaft 4 and the differential housing 31 into a whole, so that the differential function of the differential is forcibly locked. The half-shafts 4 on both sides rotate synchronously to output power, enabling the vehicle to pass smoothly through slippery sections such as sand pits and mud, improving the vehicle's passability and adaptability to complex road conditions.

[0024] The outer end of the half-shaft 4 passes through the planetary carrier 22, the sun gear 21, and the motor 1, and is connected to the drive wheel. Support bearings can be installed in the inner cavities of the planetary carrier 22, the planetary gear 21, and the motor 1 to effectively support the half-shaft 4, thereby improving the reliability of the support for the half-shaft 4 and enhancing the reliability of the transmission.

[0025] The technical solutions of the embodiments of this utility model have been fully described above with reference to the accompanying drawings. It should be noted that the described embodiments are only a part of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

Claims

1. A coaxial electric drive axle with two motors, two sets of planetary gears, a differential and half shafts assembled at the left and right ends of the differential, the motors, planetary gears, differential and half shafts being coaxially arranged, characterized in that: Two planetary gear sets are symmetrically arranged on the left and right sides of the differential. The left and right ends of the differential housing are connected to the output ends of the planetary gear sets via clutches. The output ends of one planetary gear set are equipped with a differential lock assembly that can lock the differential function of the differential. The input ends of each planetary gear set are connected to the shaft end of a motor.

2. The dual-motor coaxial electric drive bridge according to claim 1, characterized in that: The planetary gear set includes a sun gear connected to the motor, a planet carrier, a planetary shaft rotatably mounted on the planet carrier, a first planetary gear coaxially fixed on the planetary shaft and meshing with the sun gear, a gear ring fixed to the bridge housing of the electric drive bridge, and a second planetary gear coaxially fixed on the planetary shaft and meshing with the gear ring. The outer diameter of the first planetary gear is larger than the outer diameter of the second planetary gear. The two planet carriers are respectively connected to the differential housing via clutches.

3. The dual-motor coaxial electric drive bridge according to claim 2, characterized in that: The output end of the planetary carrier has an integrally formed connecting gear. The clutch is a clutch sleeve that is slidably mounted on the differential housing along the axial direction. The clutch sleeve is located on the side of the corresponding connecting gear and slides towards the connecting gear to engage with it.

4. The dual-motor coaxial electric drive bridge according to claim 3, characterized in that: The differential lock assembly includes a locking sleeve that is slidably mounted on the output end of a planetary carrier along the axial direction and a locking gear that is coaxially fixed on the half shaft and corresponds to the locking sleeve. The locking sleeve can slide along the axial direction to engage with the locking gear.

5. The dual-motor coaxial electric drive bridge according to claim 1, characterized in that: The outer end of the half-shaft passes through the planetary carrier, the sun gear, and the motor, and is connected to the drive wheel.

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