Double-planet-row integrated electric drive system and electric loader

Abstract

The invention belongs to the technical field of vehicle control, and discloses a double-planet-row integrated electric drive system and an electric loader.The electric drive system comprises a first motor, a second motor, a first planet row and a second planet row, the output end of the first motor is provided with a first driving wheel, and the first driving wheel is meshed with a driven wheel; the driven wheel is in transmission connection with the first planet row, an output shaft is arranged at the output end of the first planet row and used for being connected with a driven body so that the driven body can operate in different operation modes, and a second driving wheel is arranged at the output end of the second motor and is in transmission connection with the second planet row. The first planet row is in transmission connection with the second planet row, a locking unit is arranged at the output end of the second planet row, and the first planet row is in transmission connection with the second planet row, so that different working condition requirements can be met; and a locking unit at the output end of the second planet row can control power transmission according to actual requirements, and controllability and stability of the whole driving system are enhanced.

Description

Technical Field

[0001] This invention belongs to the field of vehicle control technology and relates to a dual planetary gear integrated electric drive system and an electric loader. Background Technology

[0002] As a typical high-energy-consuming and high-emission equipment, the power system of a pure electric loader determines the overall operating efficiency, energy economy, and market competitiveness of the machine. Existing electric loaders include two types: single-motor direct drive and single-motor combined with an automatic manual transmission (AMT).

[0003] The peak power and continuous power requirements of a single-motor direct drive motor are mismatched, making it difficult to simultaneously meet the high torque required for low-speed loading and the high efficiency requirements for high-speed travel. Under continuous heavy-load operation, the motor is prone to overheating, and the efficiency curve drops sharply. Although a single motor combined with a mechanical automatic transmission expands the torque output range, power interruption occurs during gear shifting, affecting the smoothness of operation and continuous production efficiency.

[0004] Dual-motor drives, such as the XC975-EV loader, employ "coupled dual-motor gearbox-less drive" technology. Through the coordinated operation of the two motors, a wider torque output range and faster dynamic response can be achieved. However, the use of parallel shaft or simple series mechanical layouts fails to fully utilize the compactness and multi-mode advantages of planetary gear transmissions, and there is still room for further improvement in energy recovery efficiency. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a dual planetary gear integrated electric drive system and an electric loader.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a dual planetary gear integrated electric drive system, including a first motor, a second motor, a first planetary gear set, and a second planetary gear set. The output end of the first motor is provided with a first driving gear, which meshes with a driven gear. The driven gear is driven by the first planetary gear set. The output end of the first planetary gear set is provided with an output shaft, which is used to connect to the driven body, enabling the driven body to perform different operating modes. The output end of the second motor is provided with a second driving gear, which is driven by the second planetary gear set. The first planetary gear set is driven by the second planetary gear set. The output end of the second planetary gear set is provided with a locking unit.

[0007] Furthermore, the first driving wheel includes a first driving wheel A and a first driving wheel B, with the first driving wheel B disposed on one side of the first driving wheel A, and the output end of the first driving wheel B being used for transmission connection with the power take-off.

[0008] Furthermore, a power take-off driven wheel is provided between the first driving wheel B and the power take-off, the first driving wheel B and the power take-off driven wheel are connected in a driving connection, and the power take-off driven wheel is connected in a driving connection with the power take-off.

[0009] Furthermore, the operating modes include walking mode, stationary power take-off mode, walking power take-off mode, and energy recovery mode.

[0010] Furthermore, the second motor transmits power to the first planetary gear set through the second planetary gear set. The first motor is used to dynamically adjust the torque of the first planetary gear set according to the real-time load requirements of the driven body, so that the driven body enters the walking mode.

[0011] Furthermore, when the second motor is in a free-rotating state, the first motor is used to drive the hydraulic system in the driven body through the first planetary gear set, so that the driven body enters the stationary power take-off mode.

[0012] Furthermore, the second motor transmits power to the first planetary gear set through the second planetary gear set. While the first motor balances the torque through the first planetary gear set, it also drives the hydraulic system in the driven body, causing the driven body to enter the walking power take-off mode.

[0013] Furthermore, when the driven entity drives the first motor and the second motor in reverse through the first planetary gear set and the second planetary gear set to generate electricity, the driven entity enters the energy recovery mode.

[0014] Furthermore, the first drive wheel A and the first drive wheel B are coaxially arranged.

[0015] The present invention also provides an electric loader, wherein the electric loader is equipped with the above-mentioned dual planetary gear integrated electric drive system.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: This invention discloses a dual planetary gearbox integrated electric drive system. The first driving gear at the output of the first motor meshes with the driven gear, thereby transmitting power to the first planetary gearbox. The output shaft of the first planetary gearbox is connected to the driven body, providing power to the driven body and enabling different operating modes. The second driving gear at the output of the second motor directly transmits power to the second planetary gearbox, and the first and second planetary gearboxes are connected by a transmission mechanism to adapt to different operating conditions. The locking unit at the output of the second planetary gearbox can control the power transmission according to actual needs, enhancing the controllability and stability of the entire drive system.

[0017] This invention discloses a dual planetary gear integrated electric drive system. A power take-off (PTO) driven gear is provided between the first driving gear B and the PTO, allowing for flexible adjustment of the transmission ratio between the first driving gear B and the PTO. This makes the power transmission more closely match the load requirements of the PTO operation, while effectively buffering the impact load during power transmission, reducing vibration and wear, and improving the stability and durability of the PTO transmission. In addition, it avoids power fluctuations during PTO operation from interfering with the main drive link where the first driving gear A is located, ensuring that the main drive and the PTO transmission operate independently and stably.

[0018] This invention discloses a dual planetary gear integrated electric drive system with operating modes including walking mode, stationary power take-off mode, walking power take-off mode, and energy recovery mode, covering the usage requirements of different work scenarios. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a dual planetary gear integrated electric drive system according to the present invention; Figure 2 This is a schematic diagram of the travel mode in a dual planetary gear integrated electric drive system of the present invention; Figure 3 This is a schematic diagram of the in-situ power take-off mode in a dual planetary gear integrated electric drive system of the present invention; Figure 4 This is a schematic diagram of the walking power take-off mode in a dual planetary gear integrated electric drive system of the present invention; Figure 5 This is a schematic diagram of an energy recovery mode in a dual planetary gear integrated electric drive system according to the present invention.

[0020] Figure label: 1-First motor; 2-First driving wheel A; 3-Driven wheel; 4-First driving wheel B; 5-Power take-off driven wheel; 6-Power take-off; 7-First planetary gear set; 8-Second motor; 9-Locking unit; 10-Second planetary gear set; 11-Second driving wheel; 12-Output shaft. Detailed Implementation

[0021] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0022] Traditional single-motor, single-planetary-gear electric drive systems often suffer from limited power output modes, limited torque adjustment range, and inability to simultaneously meet the power requirements for both walking and auxiliary operations. This invention presents a dual-planetary-gear integrated electric drive system. Through dual motors and dual planetary gears, it innovatively constructs a multi-path power transmission architecture, achieving seamless switching between four operating modes: walking, stationary power take-off, walking power take-off, and energy recovery. This improves power coupling efficiency and functional scalability. The dual motors are a first motor 1 and a second motor 8, and the dual planetary gears are a first planetary gear 7 and a second planetary gear 10. The first motor 1 and the second motor 8, as power sources, possess advantages such as rapid start-up response, stable torque output, and a wide speed range, enabling independent power output or combined drive according to the needs of different operating modes.

[0023] Example 1 This invention discloses a dual planetary gear integrated electric drive system, such as... Figure 1 As shown, the system includes a first motor 1, a second motor 8, a first planetary gear set 7, and a second planetary gear set 10. The first motor 1 has a first driving gear at its output end, which meshes with a driven gear 3. The driven gear 3 is driven by the first planetary gear set 7. The first planetary gear set 7 has an output shaft 12 at its output end, which connects to the driven body, enabling the driven body to operate in different modes. The second motor 8 has a second driving gear 11 at its output end, which is driven by the second planetary gear set 10. The first planetary gear set 7 is also driven by the second planetary gear set 10. The second planetary gear set 10 has a locking unit 9 at its output end. Through the integrated design of the dual motors and dual planetary gear sets, flexible switching between multiple operating modes and efficient power transmission are achieved. The dual motors can precisely output power according to different working conditions, ensuring both power performance under heavy loads and energy efficiency under light loads.

[0024] The first driving wheel includes a first driving wheel A2 and a first driving wheel B4. The first driving wheel B4 is located on one side of the first driving wheel A2, and its output end is used for transmission connection with the power take-off (PTO) 6. A PTO driven wheel 5 is provided between the first driving wheel B4 and the PTO 6. The first driving wheel B4 is transmissionally connected to the PTO driven wheel 5, and the PTO driven wheel 5 is transmissionally connected to the PTO 6.

[0025] The output end of the first motor 1 is equipped with a first driving wheel, which adopts a split design, comprising two parts: a first driving wheel A2 and a first driving wheel B4. The first driving wheels A2 and B4 are coaxially arranged, sharing the same output shaft to ensure absolute synchronization and stability during power transmission, avoiding power loss, mechanical impact, and gear wear caused by asynchronous transmission. The first driving wheel B4 is located on one side of the first driving wheel A2, and its output end is used to drively connect with the power take-off (PTO) 6 to achieve power take-off functionality. A PTO driven wheel 5 is provided between the first driving wheel B4 and the PTO 6, and their driving connection reduces noise and vibration during transmission. The PTO driven wheel 5's connection to the PTO 6 allows for quick engagement and disengagement according to operational requirements.

[0026] The first driving gear A2 meshes with the driven gear 3, and the driven gear 3 is connected to the first planetary gear set 7 via a transmission. The output end of the first planetary gear set 7 is equipped with an output shaft 12, which is used to connect to the driven body. Different control strategies enable the driven body to operate in different modes. The first planetary gear set includes a sun gear, planet gears, a planet carrier, and a ring gear, enabling the convergence and distribution of multiple power sources.

[0027] The sun gear is fixedly connected to the driven gear 3 and directly receives power input from the first motor 1; the planet gears are evenly arranged on the planet carrier through planet shafts and mesh with the sun gear and the ring gear to transmit power and split torque; the planet carrier is the final power output end of the first planetary gear set 7 and is fixedly connected to the output shaft 12; the ring gear is driven by the second planetary gear set 10 through gear meshing to realize power coupling between the two planetary gear sets.

[0028] The output end of the second motor 8 is equipped with a second drive gear 11, which is connected to the second planetary gear set 10 via a transmission connection. The second planetary gear set 10 also adopts a planetary gear structure and is mainly responsible for regulating and transmitting the power of the second motor 8. The first planetary gear set 7 is connected to the second planetary gear set 10 via a transmission connection, realizing power coupling. The output end of the second planetary gear set 10 is equipped with a locking unit 9, which is used to lock the planet carrier of the second planetary gear set 10 and change the power transmission path.

[0029] The structure of the second planetary gear set 10 is similar to that of the first planetary gear set 7. It also consists of a sun gear, planet gears, planet carriers and a ring gear. It is mainly responsible for regulating and transmitting the power of the second motor 8. Unlike the first planetary gear set 7, the planet carrier of the second planetary gear set 10 is connected to the locking unit 9.

[0030] The locking unit 9 employs a hydraulically controlled structure, capable of locking or releasing the planet carrier of the second planetary gear set 10 according to system control commands, thereby altering the power transmission path. When the locking unit 9 is locked, the planet carrier of the second planetary gear set 10 remains stationary. At this time, the power from the second motor 8 is transmitted to the ring gear of the second planetary gear set 10 via the second drive wheel 11, driving the planetary gears to rotate around the sun gear, which in turn drives the sun gear to output power. When the locking unit 9 is released, the planet carrier of the second planetary gear set 10 can rotate freely, changing the power transmission path and enabling different operating modes. The first planetary gear set 7 and the second planetary gear set 10 are connected via the meshing of the ring gear, allowing for efficient power coupling between the two planetary gear sets.

[0031] The dual planetary gear integrated electric drive system can achieve four operating modes: walking mode, stationary power take-off mode, walking power take-off mode, and energy recovery mode. Walking mode is suitable for mobile working conditions, such as the relocation of construction machinery; stationary power take-off mode is suitable for when the driven body is stationary, such as excavators digging in place or cranes lifting in place; walking power take-off mode is suitable for driving auxiliary work while the driven body is moving, such as loaders performing loading operations while moving, pavers performing paving operations while moving, and water trucks performing watering operations while moving; energy recovery mode is used when the driven body encounters downhill or braking conditions, converting inertial mechanical energy into electrical energy for recovery and storage.

[0032] The second motor 8 transmits power to the first planetary gear set 7 through the second planetary gear set 10. The first motor 1 is used to dynamically adjust the torque of the first planetary gear set 7 according to the real-time load requirements of the driven body, so that the driven body enters the walking mode.

[0033] like Figure 2As shown, in walking mode, locking unit 9 activates and locks the planet carrier of the second planetary gear set 10, making the planet carrier of the second planetary gear set 10 fixed. The second motor 8, acting as the main drive source, starts, and its output power is transmitted to the ring gear of the second planetary gear set 10 via the second drive wheel 11. Because the planet carrier is locked, the rotation of the ring gear causes the planetary gears to rotate around their own axes while simultaneously revolving around the sun gear, thus driving the sun gear of the second planetary gear set 10 to rotate and output power. The sun gear of the second planetary gear set 10 is connected to the ring gear of the first planetary gear set 7 via gear meshing, transmitting power to the ring gear of the first planetary gear set 7. Simultaneously, the first motor 1 transmits power to the sun gear of the first planetary gear set 7 via the first drive wheel A2 and the driven wheel 3. The first motor 1 primarily serves to regulate and balance torque. The sun gear and ring gear of the first planetary gear set 7 receive power from the first motor 1 and the second motor 8 respectively, achieving power coupling and torque distribution through the planetary gears. Finally, the planet carrier transmits the integrated power to the output shaft 12, driving the driven body to move. In walking mode, the output torque of the first motor 1 and the second motor 8 is dynamically adjusted according to real-time load changes. When the load is small, only the second motor 8 drives independently, thereby achieving energy-saving operation. When the load is large, the first motor 1 and the second motor 8 drive together to ensure stability and power under complex walking conditions such as climbing and heavy load.

[0034] The locking unit 9 enables the system to quickly change the power transmission path according to different operating conditions, thereby optimizing transmission efficiency.

[0035] The second motor 8 transmits power to the first planetary gear set 7 through the second planetary gear set 10. The first motor 1 balances the torque through the first planetary gear set 7 and drives the hydraulic system in the driven body, so that the driven body enters the walking power take-off mode.

[0036] like Figure 3 As shown, in the stationary power take-off mode, the driven body remains stationary, and the second motor 8 is in a free-rotating state, providing no driving torque. The first motor 1, as a power source, outputs power simultaneously through the first driving wheel A2 and the first driving wheel B4. The first driving wheel B4 drives the power take-off unit 6 through the driven wheel 5 of the power take-off unit. The first driving wheel A2 transmits power to the sun gear of the first planetary gear set 7 through the driven wheel 3, driving the planet gears and planet carrier of the first planetary gear set 7 to rotate, and driving the hydraulic system in the driven body through the output shaft 12. The output torque of the first motor 1 can be precisely adjusted according to the load requirements of the auxiliary working device to avoid power waste.

[0037] like Figure 4As shown, in the walking power take-off mode, both walking and power take-off needs must be met simultaneously. The second motor 8 transmits power to the ring gear of the first planetary gear set 7 through the second drive wheel 11 and the second planetary gear set 10, providing the main driving force to the driven body. Simultaneously, the first motor 1, on the one hand, transmits power to the sun gear of the first planetary gear set 7 through the first drive wheel A2 and the driven wheel 3, ensuring the stability of the walking power; on the other hand, it drives the power take-off unit 6 through the first drive wheel B4 and the power take-off unit driven wheel 5. In the walking power take-off mode, the output torque of the first motor 1 and the second motor 8 is dynamically adjusted to avoid equipment instability or decreased operating efficiency due to unreasonable power distribution. When encountering sudden heavy loads during walking, the output torque of the second motor 8 can be increased, while the torque distribution ratio of the first motor 1 is adjusted.

[0038] When the driven entity generates electricity by reverse-drives the first motor 1 and the second motor 8 through the first planetary gear set 7 and the second planetary gear set 10, the driven entity enters the energy recovery mode.

[0039] like Figure 5 As shown, in energy recovery mode, when the driven body encounters a downhill slope or braking, it reverses the first planetary gear set 7 and the second planetary gear set 10 to drive the first motor 1 and the second motor 8 to generate electricity, thus entering energy recovery mode. At this time, the first motor 1 and the second motor 8 switch to generator mode, converting mechanical energy into electrical energy for recovery, thereby improving the energy efficiency ratio of the entire system.

[0040] The planet carrier of the first planetary gear set 7 drives the planetary gears to rotate, which in turn drives the sun gear and the ring gear to rotate in the opposite direction. The sun gear drives the first motor 1 in the opposite direction via the driven gear 3 and the first driving gear A2. The ring gear, through its meshing with the second planetary gear set 10, drives the sun gear of the second planetary gear set 10 to rotate in the opposite direction, which in turn drives the second motor 8 in the opposite direction via the second driving gear 11. Under the action of the reverse driving force, the first motor 1 and the second motor 8 switch to generator mode, converting the input mechanical energy into electrical energy. The generated electrical energy is processed by power electronic devices such as inverters and controllers and then stored in the power battery pack, realizing energy recovery and utilization. In energy recovery mode, the recovery power is dynamically adjusted according to the operating conditions (such as slope gradient, braking intensity, etc.) to ensure the safety and efficiency of the recovery process. When the slope is steep and the equipment deceleration requirement is high, the energy recovery power can be increased.

[0041] In summary, the dual planetary gearbox integrated electric drive system achieves flexible power source allocation and seamless switching between multiple operating modes through dual motors and dual planetary gearboxes. The transmission connection between the first planetary gearbox 7 and the second planetary gearbox 10 enables the first motor 1 and the second motor 8 to work collaboratively, either independently or in combination. The locking unit 9 allows the electric drive system to change the power transmission path according to different working conditions, optimizing transmission efficiency. The power take-off 6 enables the system to provide power to auxiliary equipment such as hydraulic systems while meeting the walking requirements, improving the system's functional integration and operational flexibility.

[0042] The present invention also provides an electric loader, wherein the electric loader is equipped with the above-mentioned internal double planetary gear integrated electric drive system.

[0043] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

Claims

1. A double planetary row integrated electric drive system, characterized in that: comprising a first motor (1), a second motor (8), a first planetary row (7) and a second planetary row (10), the output end of the first motor (1) is provided with a first driving wheel, the first driving wheel is meshed with a driven wheel (3), the driven wheel (3) is transmission connected with the first planetary row (7), the output end of the first planetary row (7) is provided with an output shaft (12), the output shaft (12) is used for connecting a driven body, so that the driven body is in different operation modes, the output end of the second motor (8) is provided with a second driving wheel (11), the second driving wheel (11) is transmission connected with the second planetary row (10), the first planetary row (7) and the second planetary row (10) are transmission connected, and the output end of the second planetary row (10) is provided with a locking unit (9).

2. The double planetary row integrated electric drive system according to claim 1, characterized in that: the first driving wheel comprises a first driving wheel A (2) and a first driving wheel B (4), the first driving wheel B (4) is arranged on one side of the first driving wheel A (2), and the output end of the first driving wheel B (4) is used for transmission connection with a power takeoff (6).

3. The double planetary row integrated electric drive system according to claim 2, characterized in that: a power takeoff driven wheel (5) is arranged between the first driving wheel B (4) and the power takeoff (6), the first driving wheel B (4) is transmission connected with the power takeoff driven wheel (5), and the power takeoff driven wheel (5) is transmission connected with the power takeoff (6).

4. The double planetary row integrated electric drive system according to claim 1, characterized in that: the operation mode comprises a walking mode, a power takeoff mode, a walking power takeoff mode and an energy recovery mode.

5. The double planetary row integrated electric drive system according to claim 4, characterized in that: the second motor (8) transmits power to the first planetary row (7) through the second planetary row (10), and the first motor (1) is used for dynamically adjusting the torque of the first planetary row (7) according to the real-time load demand of the driven body, so that the driven body enters the walking mode.

6. The double planetary row integrated electric drive system according to claim 5, characterized in that: when the second motor (8) is in a free random rotation state, the first motor (1) is used for driving the hydraulic system in the driven body through the first planetary row (7), so that the driven body enters the power takeoff mode.

7. The double planetary row integrated electric drive system according to claim 6, characterized in that: the second motor (8) transmits power to the first planetary row (7) through the second planetary row (10), and the first motor (1) drives the hydraulic system in the driven body while balancing the torque through the first planetary row (7), so that the driven body enters the walking power takeoff mode.

8. The double planetary row integrated electric drive system according to claim 7, characterized in that: when the driven body drives the first motor (1) and the second motor (8) to generate electricity through the first planetary row (7) and the second planetary row (10) in reverse, the driven body enters the energy recovery mode. ​ ​ ​ ​ ​ ​ ​ ​ 9. The dual planetary array integrated electric drive system of claim 2, wherein: the first driving wheel A (2) and the first driving wheel B (4) are coaxially arranged.

10. An electrically powered loader characterized by The electric loader is provided with the dual planetary array integrated electric drive system according to any one of claims 1-9.

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