Engineering machinery electric drive system and electric loader

Abstract

The invention discloses an engineering machinery electric driving system and an electric loader, the system comprises a first driving main body, a first driving main body driving wheel and a first driving main body second driven wheel are arranged on the driving end of the first driving main body at intervals, and the bottom of the first driving main body driving wheel is connected with the first driving main body first driven wheel; the power take-off equipment is connected with the first driving main body and the second driven wheel through a power take-off driven wheel; the driving end of the second driving main body is connected with a second driving main body driving wheel, the second driving main body driving wheel is connected with a second driving main body driven wheel, and the second driving main body driven wheel is connected with the first driving main body first driven wheel through a planet row; and the output shaft is connected with the planet row and is used for being connected with a driven main body. According to the system, the dual-motor direct drive technology is adopted, and it is guaranteed that power is not interrupted in the gear shifting process; and meanwhile, the special external power take-off requirement of the engineering machinery can be met, and the complexity and the fault occurrence rate of an engineering machinery system are solved.

Description

Technical Field

[0001] This invention belongs to the technical field of electric drive systems for construction machinery, and specifically relates to an electric drive system for construction machinery and an electric loader. Background Technology

[0002] In the field of construction machinery, the electric drive system is a core power transmission and control component, and its performance directly affects the operating efficiency, reliability and cost of construction machinery. At present, the electric drive system of construction machinery mainly adopts three technical architectures: single motor direct drive, single motor multi-speed drive and multi-motor coupled drive. However, each architecture has certain limitations in practical applications.

[0003] Single-motor direct-drive systems have a simple structure and certain advantages in design and manufacturing. However, due to their narrow high-efficiency range, in order to meet the different needs of construction machinery in low-speed, high-torque conditions (such as heavy-duty lifting and excavation) and high-speed driving conditions (such as equipment relocation), the motor often needs to be over-designed. This over-design not only leads to a significant increase in motor cost, but also reduces the efficiency of the motor when it is running in the non-efficient range, resulting in serious energy waste, which is not in line with the current development trend of energy conservation and emission reduction.

[0004] The single-motor-multi-speed transmission scheme improves torque output characteristics to some extent, allowing the motor to operate within a more suitable speed and torque range by switching between different gears. However, power interruption inevitably occurs during gear shifting. This problem is particularly prominent in construction machinery such as excavators and loaders that require precise operation. Power interruption can seriously affect the continuity and accuracy of operations, reduce work efficiency, and may even have adverse effects on work quality and equipment safety.

[0005] At the same time, the existing dual-motor planetary gear system has the problem of limited functionality in construction machinery applications. It does not fully consider the unique external power take-off requirements of construction machinery. In actual operation, construction machinery has to be equipped with a dedicated power take-off motor, which not only increases the complexity of the system and the probability of failure, but also increases the system cost by more than 30%, which has an adverse impact on the market competitiveness of the product. Summary of the Invention

[0006] The purpose of this invention is to provide an electric drive system for construction machinery and an electric loader. On the one hand, it addresses the shortcomings of existing single-motor direct drive systems and single-motor multi-speed transmission schemes in construction machinery applications. On the other hand, it addresses the technical defects of existing dual-motor planetary gear system systems in construction machinery applications that do not fully consider the unique external power take-off requirements of construction machinery, forcing construction machinery to be equipped with an additional dedicated power take-off motor, which not only increases the complexity of the system but also increases the probability of failure.

[0007] To achieve the above objectives, the present invention employs the following technical solution: In a first aspect, an electric drive system for engineering machinery is provided, comprising: The first driving body has a first driving body driving wheel and a first driving body second passive wheel spaced apart on its driving end, and the bottom of the first driving body driving wheel is connected to the first driving body first passive wheel; The power take-off device is connected to the second passive wheel of the first drive body via a power take-off passive wheel; The second drive body has a drive wheel connected to its drive end, a driven wheel connected to the drive wheel, and a driven wheel connected to the drive wheel. The driven wheel is connected to the first driven wheel of the first drive body via a planetary gear set. An output shaft is connected to the planetary gear set, and the output shaft is used to connect to the driven body. In this process, the driven body operates in different modes through the coordinated action of the first and second driving bodies.

[0008] Furthermore, the movement modes include walking mode, stationary power-taking mode, walking-power-taking combined mode, and energy recovery mode; When the second drive unit is the main drive source, the first drive unit is used to dynamically adjust the planetary gear torque according to the real-time load requirements of the driven body, so that the driven body enters the walking mode. When the second drive body is in a free-rotating state, the first drive body is used to drive the hydraulic system in the driven body through the planetary gear set so that the driven body enters the stationary power take-off mode. When the first drive body drives the planetary gear set to output the walking torque, the first drive body is used to balance the torque through the planetary gear set and drive the hydraulic system in the driven body so that the driven body enters the walking power take-off compound mode. When the driven entity drives the first and second driving entities in reverse through the planetary gear set to generate electricity, the driven entity enters the energy recovery mode.

[0009] Furthermore, the first drive body, the second drive body, and the output shaft are parallel to each other.

[0010] Furthermore, the first driving body's driving wheel and the first driving body's first driven wheel are axially parallel, and the first driving body's first driven wheel and the planetary gear set are axially parallel.

[0011] Furthermore, the diameter of the active wheel of the first driving body is smaller than the diameter of the passive wheel of the first driving body.

[0012] Furthermore, the diameters of the second passive wheel of the first driving body, the power take-off passive wheel, and the driving wheel of the second driving body are equal.

[0013] Furthermore, the diameter of the driving wheel of the second driving body is smaller than the diameter of the driven wheel of the second driving body.

[0014] Furthermore, the diameter of the active wheel of the first driving body is equal to the diameter of the passive wheel of the second driving body.

[0015] Furthermore, both the first driving body and the second driving body are motors; The power take-off device is a power take-off unit.

[0016] Secondly, an electric loader is provided, which is equipped with the engineering machinery electric drive system described above.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The system adopts dual-motor direct drive technology, which not only ensures high efficiency and full energy utilization when operating in non-efficient areas, but also ensures uninterrupted power during gear shifting when applied to construction machinery operations. At the same time, because the system is equipped with a power take-off device, it can meet the unique external power take-off requirements of construction machinery without the need for additional motors, thus solving the complexity and failure rate of construction machinery systems. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This invention provides a schematic diagram of an electric drive system assembly for engineering machinery. Figure 2 This invention provides a schematic diagram of the travel mode in an electric drive system for engineering machinery. Figure 3 This invention provides a schematic diagram of an in-situ power take-off mode in an electric drive system for engineering machinery. Figure 4 This invention provides a schematic diagram of a combined power take-off and travel mode in an electric drive system for engineering machinery. Figure 5 A schematic diagram of energy recovery in an electric drive system for engineering machinery provided by the present invention; Wherein: 1. First drive body; 2. First drive body driving wheel; 3. First drive body first driven wheel; 4. First drive body second driven wheel; 5. Power take-off driven wheel; 6. Power take-off device; 7. Planetary gear set; 8. Second drive body; 9. Second drive body driving wheel; 10. Second drive body driven wheel; 11. Output shaft. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0022] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0023] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0025] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0026] To address the technical deficiencies mentioned in the background section, this embodiment provides an electric drive system for engineering machinery and an electric loader. The invention will be further described in detail below with reference to the accompanying drawings: In a first aspect, embodiments of the present invention provide an electric drive system for engineering machinery, such as... Figure 1 As shown, the system includes a first drive body 1, with a first drive body driving wheel 2 and a first drive body second driven wheel 4 spaced apart on its drive end. The bottom of the first drive body driving wheel 2 is connected to the first drive body first driven wheel 3. A power take-off device 6 is connected to the first drive body second driven wheel 4 via a power take-off driven wheel 5. A second drive body 8 has a second drive body driving wheel 9 connected to its drive end. The second drive body driving wheel 9 is connected to a second drive body driven wheel 10. The second drive body driven wheel 10 and the first drive body first driven wheel 3 are connected via a planetary gear set 7. An output shaft 11 is connected to the planetary gear set 7 and is used to connect to the driven body. Under the coordinated action of the first drive body 1 and the second drive body 8, the driven body can operate in different modes.

[0027] In the above structure, since the power take-off device 6 is connected to the second passive wheel 4 of the first drive body through the power take-off passive wheel 5, the system can meet the external power take-off requirements of engineering machinery without the need for an additional dedicated power take-off motor. This not only simplifies the system structure, reduces the number of parts, reduces system complexity and the probability of failure, but also significantly saves costs.

[0028] In addition, regarding the power, the driven wheel 10 of the second drive unit is connected to the first driven wheel 3 of the first drive unit via a planetary gear set 7. The planetary gear set 7, as a highly efficient transmission device, has multiple degrees of freedom and can achieve complex power distribution and transmission. Under the synergistic action of the first drive unit 1 and the second drive unit 8, the planetary gear set 7 can flexibly distribute the power of the two drive units according to different working conditions and load requirements, enabling the system to maintain efficient power transmission in different motion modes, improving energy utilization and reducing energy consumption.

[0029] Compared with a single motor paired with a multi-speed transmission, this system, through the cooperation of a dual-drive main body and a planetary gear set of 7, avoids the problem of power interruption during gear shifting, ensuring smooth power transmission of construction machinery when switching between various motion modes, thus improving work efficiency and quality.

[0030] Furthermore, through its rational component layout and connection method, this system avoids the problem of excessive axial dimensions in traditional dual planetary gear 7-speed systems, making it easier to install the electric drive system on the chassis of construction machinery and improving the utilization rate of the chassis space.

[0031] Furthermore, in practice, the electric drive system of this construction machinery has the following movement modes: walking mode, stationary power take-off mode, walking power take-off combined mode, and energy recovery mode. The driven main body is an electric loader. When the second drive unit 8 acts as the main drive source, the first drive unit 1 dynamically adjusts the torque of the planetary gear set 7 according to the real-time load requirements of the driven body, so that the driven body enters the walking mode; for example Figure 2 As shown, in the high-efficiency walking mode, the power system of the electric loader drives the vehicle with optimal efficiency. The second drive body 8 serves as the main drive source, and power is input through the ring gear in the planetary gear set 7. The first drive body 1 works in a torque balance state at this time. According to the real-time load demand of the electric loader, the torque distribution is dynamically adjusted through the sun gear in the planetary gear set 7, so that the first drive body 1 and the second drive body 8 are always in the high-efficiency working range.

[0032] Planetary gear set 7 serves as the main output end, transmitting the combined torque to the drive axle of the electric loader to achieve a maximum driving speed of 40 km / h. Meanwhile, the hydraulic system in the electric loader is in standby mode. The main hydraulic pump is driven by the first drive unit 1 through the power take-off device 6 to maintain a minimum pressure (approximately 5 MPa) to meet the basic requirements of the electric loader, such as steering. At this time, the energy management system of the electric loader prioritizes the use of the power battery for power supply. When long-distance driving conditions are detected, it will automatically switch to the fuel cell as the main power supply mode.

[0033] When the second drive body 8 is in a free-rotating state, the first drive body 1 is used to drive the hydraulic system in the driven body through the planetary gear set 7 so that the driven body enters the stationary power take-off mode. like Figure 3 As shown, during implementation, the second drive body 8 is in a free-rotating state (0 torque output), and the first drive body 1 is locked at the optimal power take-off speed (1500-1800 rpm), directly driving the hydraulic system in the electric loader through the sun gear in the planetary gear set 7; at this time, the ring gear of the planetary gear set 7 is locked by the brake of the electric loader, and the power of the first drive body 1 is dedicated to power take-off output.

[0034] The intelligent control system of the electric loader automatically adjusts the speed of the first drive unit 1 according to the bucket position and material resistance, so as to achieve the operating characteristics of high speed under light load and low speed under heavy load, which saves 15-20% energy compared with the fixed speed solution. The energy management system of the electric loader adopts a pure battery power supply mode. When continuous heavy load operation is detected, the supercapacitor will intervene to provide peak power and limit the battery discharge current within a safe range.

[0035] When the first drive body 1 drives the planetary gear 7 to output walking torque, the first drive body 1 is used to balance the torque through the planetary gear 7 while driving the hydraulic system in the driven body, so that the driven body enters the walking power take-off compound mode. like Figure 4 As shown, in implementation, the electric loader system needs to simultaneously meet the requirements of driving and operation. The first drive unit 1 drives the planetary carrier through the ring gear in the planetary gear set 7 to output the driving torque, which can provide a maximum traction force of 160kN. The first drive unit 1 also drives the hydraulic pump of the electric loader system through the sun gear in the planetary gear set 7 to balance the torque and provide the working device with a maximum of about 60% of the total power of the system. At this time, the dual motors adopt a dynamic power distribution algorithm to monitor the driving resistance and hydraulic load in real time: when the loading resistance increases, the torque of the first drive unit 1 automatically decreases by 10~15% to ensure that the hydraulic system receives sufficient power first; when the driving resistance increases, the torque of the second drive unit 8 can be instantly increased to the peak torque.

[0036] When the driven body drives the first driving body 1 and the second driving body 8 in reverse through the planetary array 7 to generate electricity, the driven body enters the energy recovery mode.

[0037] like Figure 5 As shown, in practice, the kinetic energy of the electric loader drives the first drive body 1 and the second drive body 8 in reverse through the planetary carrier in the planetary gear set 7 to generate electricity; when the electric loader is going downhill or braking, the second drive body 8 works as the main generator; the first drive body 1 selectively generates electricity or maintains hydraulic pressure according to the hydraulic system requirements of the electric loader.

[0038] In this scheme, when the electric drive system of the engineering machinery is installed on the electric loader, the first drive body 1 and the second drive body 8 are both selected as motors, and the power take-off device 6 is selected as a power take-off unit; during the installation process, the first drive body 1, the second drive body 8 and the output shaft 11 are parallel to each other, the first drive body drive wheel 2 and the first drive body first driven wheel 3 are axially parallel, and the first drive body first driven wheel 3 and the planetary gear set 7 are axially parallel.

[0039] Among them, the diameter of the first driving body driving wheel 2 is smaller than the diameter of the first driving body first passive wheel 3, the diameters of the first driving body second passive wheel 4, the power take-off passive wheel 5 and the second driving body driving wheel 9 are equal, the diameter of the second driving body driving wheel 9 is smaller than the diameter of the second driving body passive wheel 10, and the diameter of the first driving body driving wheel 2 is equal to the diameter of the second driving body passive wheel 10.

[0040] The diameter of the first drive main body's active wheel 2 is smaller than the diameter of the first drive main body's passive wheel 3. According to the gear transmission principle, during the power transmission process, when the small gear drives the large gear to rotate, it will achieve the effect of deceleration and torque increase. This is very advantageous for electric loaders in working conditions that require large torque output, such as shoveling heavy objects. It can provide the loader with enough power to overcome greater resistance and successfully complete the shoveling operation.

[0041] Similarly, the diameter of the active wheel 9 of the second drive body is smaller than the diameter of the passive wheel 10 of the second drive body, which also enables the power output of the second drive body 8 to achieve deceleration and torque increase during transmission, further enhancing the overall torque output capability of the system and meeting the loader's demand for high torque under different complex working conditions.

[0042] The diameter of the active wheel 2 of the first drive body is equal to the diameter of the passive wheel 10 of the second drive body, which makes the two drive bodies more coordinated when power coupling. When the planetary gear 7 distributes and transmits power, the equal wheel diameter relationship helps to achieve smooth integration of the power of the two drive bodies, avoids uneven power distribution or impact and vibration during transmission caused by wheel diameter differences, and improves the stability and reliability of power transmission.

[0043] In summary, because the system adopts dual-motor direct drive technology, it not only has high efficiency and full energy utilization when operating in non-efficient areas, but also ensures uninterrupted power during gear shifting when applied to construction machinery operations. At the same time, because the system is equipped with power take-off device 6, it can meet the unique external power take-off requirements of construction machinery without the need for additional motors, thus solving the complexity and failure rate of construction machinery systems.

[0044] Secondly, an electric loader is provided, which is equipped with the engineering machinery electric drive system described above.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit its scope of protection. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading the present invention, they can still make various changes, modifications or equivalent substitutions to the specific implementation of the invention, but these changes, modifications or equivalent substitutions are all within the scope of protection of the pending claims of the invention.

Claims

1. An electric drive system for a construction machine, characterized in that, The electric drive system for engineering machinery comprises: a first driving body, a first driving body driving end is provided with a first driving body driving wheel and a first driving body second driven wheel, the bottom of the first driving body driving wheel is connected with a first driving body first driven wheel; a power taking device, the power taking device is connected with the first driving body second driven wheel through a power taking driven wheel; a second driving body, a second driving body driving end is connected with a second driving body driving wheel, the second driving body driving wheel is connected with a second driving body driven wheel, the second driving body driven wheel is connected with the first driving body first driven wheel through a planetary gear train; an output shaft, the output shaft is connected with the planetary gear train, and the output shaft is used for connecting a driven body; wherein, under the cooperation of the first driving body and the second driving body, the driven body is in different operation modes.

2. The electric drive system of the construction machine according to claim 1, characterized by, The operation modes include walking mode, power taking mode, walking and power taking compound mode and energy recovery mode; wherein, when the second driving body is used as a main driving source, the first driving body is used for dynamically adjusting the torque of the planetary gear train according to the real-time load demand of the driven body, so that the driven body enters the walking mode; when the second driving body is in a free rotation state, the first driving body is used for driving the hydraulic system in the driven body through the planetary gear train, so that the driven body enters the power taking mode; when the first driving body drives the planetary gear train to output walking torque, the first driving body is used for balancing the torque through the planetary gear train while driving the hydraulic system in the driven body, so that the driven body enters the walking and power taking compound mode; when the driven body drives the first driving body and the second driving body to generate electricity through the planetary gear train, the driven body enters the energy recovery mode.

3. The electric drive system of the construction machine according to claim 1, wherein The first driving body, the second driving body and the output shaft are parallel to each other.

4. The electric drive system of the construction machine according to claim 1, characterized by, The first driving body driving wheel and the first driving body first driven wheel are axially parallel, and the first driving body first driven wheel and the planetary gear train are axially parallel.

5. The electric drive system of the construction machine according to claim 4, wherein The diameter of the first driving body driving wheel is smaller than the diameter of the first driving body first driven wheel.

6. The electric drive system of the construction machine according to claim 1, wherein The diameters of the first driving body second driven wheel, the power taking driven wheel and the second driving body driving wheel are equal.

7. The electric drive system of the construction machine according to claim 1, wherein The diameter of the second driving body driving wheel is smaller than the diameter of the second driving body driven wheel.

8. The electric drive system of the construction machine according to claim 1, wherein The diameter of the first driving body driving wheel is equal to the diameter of the second driving body driven wheel.

9. The electric drive system of the construction machine according to claim 1, wherein The first driving body and the second driving body are both motors; The power taking device is a power taker.

10. An electrically powered loader characterized by The electric loader is provided with the engineering machinery electric drive system according to any one of claims 1-9. The electric drive system for engineering machinery comprises:

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