An electric drive system assembly for electric construction machinery

Abstract

This utility model discloses an electric drive system assembly for electric construction machinery, including a main motor, an auxiliary motor, and a parallel shaft reducer with an integrated overrunning clutch. The parallel shaft reducer has an input shaft and an output shaft. The input shaft includes a main input shaft and an auxiliary input shaft, which are connected via the overrunning clutch. The main motor and the auxiliary motor are connected to the main input shaft and the auxiliary input shaft respectively. The overrunning clutch is used to control the connection or disconnection of the power connection between the auxiliary motor and the main input shaft. The electric drive system assembly for electric construction machinery of this utility model has an extremely simple and compact structure, few parts, and low manufacturing cost. By integrating the overrunning clutch on the input shaft of the reducer, and relying on the passive mechanical characteristics of the overrunning clutch to achieve mode switching, it can achieve efficient and seamless coupling and separation of the main / auxiliary motor torque, significantly improving the smoothness of mode switching while ensuring strong power output.

Description

Technical Field

[0001] This utility model belongs to the field of electric engineering machinery drive technology, specifically relating to an electric drive system assembly for electric engineering machinery. Background Technology

[0002] With the rapid development of electrification technology, especially the increasing demands of electric construction machinery for high efficiency, high power density, high reliability and low cost of drive systems, dual-motor drive systems have gained widespread recognition due to their advantages in power performance, efficiency optimization and redundancy backup.

[0003] The following are some of the mainstream solutions currently available on the market:

[0004] (1) Parallel drive scheme of two high-power motors: Two motors of the same power (peak power usually ≥200kW) directly output power through a reducer;

[0005] (2) Single motor + power shift gearbox solution: a multi-plate wet clutch is used to achieve power coupling, but an additional hydraulic / electronic control system is required;

[0006] (3) Single motor + electromechanical shift gearbox solution: There is power interruption during shifting, poor driving experience and the reliability of the gearbox needs to be improved.

[0007] The current mainstream solutions on the market mainly have the following problems:

[0008] (1) Excessive cost: The dual high-power motors increase material costs by more than 40% (silicon steel sheets + permanent magnets account for more than 60%);

[0009] (2) The complex structure of the gearbox increases the cost of transmission components such as the gearbox by 25-35% and greatly reduces the reliability of the gearbox;

[0010] (3) Low energy efficiency: When operating at low speed, both motors work at the same time, and the actual load rate is less than 30%.

[0011] (4) The motor frequently operates in the inefficient zone (efficiency < 75%, and the utilization rate of the peak efficiency zone is only 45%).

[0012] (5) System reliability issues: Wet clutches have the risk of hydraulic leakage, and there is a possibility that hydraulic system failure may lead to clutch friction plate failure. Utility Model Content

[0013] The purpose of this utility model is to overcome the defects of the prior art and provide an electric drive system assembly for electric engineering machinery. The structure is extremely simple and compact, with few parts and low manufacturing cost. An overrunning clutch is integrated and assembled on the input shaft of the reducer. The mode switching is achieved by relying on the passive mechanical characteristics of the overrunning clutch. It can achieve efficient and seamless coupling and separation of the main and auxiliary motor torques, and significantly improve the smoothness of mode switching while ensuring strong power output.

[0014] The technical solution to achieve the above objective is: an electric drive system assembly for electric engineering machinery, comprising a main motor, an auxiliary motor, and a parallel shaft reducer with an integrated overrunning clutch, wherein:

[0015] The parallel shaft reducer has an input shaft and an output shaft. The input shaft includes a main input shaft and an auxiliary input shaft, which are connected by the overrunning clutch. A drive gear is provided on the main input shaft, and a driven gear is provided on the output shaft. The drive gear and the driven gear mesh with each other.

[0016] The main motor and the auxiliary motor are connected to the main input shaft and the auxiliary input shaft in a one-to-one correspondence;

[0017] The main motor has an output power of 120-150kW, which is only used to ensure the power requirements for high-speed driving.

[0018] The output power of the auxiliary motor is 30-45% of the output power of the main motor, and it is used to cooperate with the main motor to output power when the whole machine is operating at low speed.

[0019] The overrunning clutch is used to control the connection or disconnection of the power connection between the auxiliary motor and the main input shaft.

[0020] In the aforementioned electric drive system assembly for electric engineering machinery, the output power of the auxiliary motor is 60-80kW.

[0021] In the above-mentioned electric drive system assembly for electric construction machinery, the overrunning clutch automatically locks when the input shaft speed is ≤4500~6000rpm, corresponding to a speed of 15~20km / h for the electric construction machinery.

[0022] In the aforementioned electric drive system assembly for electric construction machinery, when a large torque output is required, the auxiliary motor starts, the overrunning clutch engages, and the torque of the auxiliary motor is directly superimposed on the main input shaft, efficiently merging with the torque of the main motor and jointly inputting it to the output shaft.

[0023] In the aforementioned electric drive system assembly for electric construction machinery, when only the main motor needs to work, the auxiliary motor stops or idles, the main input shaft rotates at a speed higher than the auxiliary motor or in the opposite direction to the auxiliary input shaft, and the overrunning clutch automatically overruns or slips, disconnecting the power connection between the auxiliary motor and the main input shaft.

[0024] The electric drive system assembly for electric construction machinery of this utility model can be applied to electric construction machinery or other fields requiring efficient power transmission, and has the following beneficial effects:

[0025] (1) The parallel shaft single-stage reducer has an extremely simple and compact structure, fewer parts, and low manufacturing cost.

[0026] (2) It can achieve efficient and seamless coupling and separation of main / auxiliary motor torque, which significantly improves the smoothness of mode switching while ensuring strong power output;

[0027] (3) Eliminate complex transmission mechanisms and additional controllable clutches and other components to reduce mechanical losses and improve system efficiency and reliability;

[0028] (4) Reduce the complexity of the control system and rely on the passive mechanical characteristics of the overrunning clutch to achieve mode switching;

[0029] (5) It has high power density and good application prospects. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the electric drive system assembly for electric engineering machinery according to this utility model. Detailed Implementation

[0031] To enable those skilled in the art to better understand the technical solution of this utility model, its specific embodiments are described in detail below with reference to the accompanying drawings:

[0032] Please see Figure 1 The preferred embodiment of this utility model is an electric drive system assembly for electric engineering machinery, including a main motor 1, an auxiliary motor 2, and a parallel shaft reducer 4 with an integrated overrunning clutch 3.

[0033] The parallel shaft reducer 4 has an input shaft 41 and an output shaft 42. The input shaft 41 includes a main input shaft 411 and an auxiliary input shaft 412, which are connected by an overrunning clutch 3. A drive gear 43 is provided on the main input shaft 411, and a driven gear 44 is provided on the output shaft 42. The drive gear 43 and the driven gear 44 mesh with each other. The input shaft 41 is mounted on an input shaft bearing 45, and the output shaft 42 is mounted on an output shaft bearing 46.

[0034] The main motor 1 and the auxiliary motor 2 are connected to the main input shaft and the auxiliary input shaft in a one-to-one correspondence. The output power of the main motor 1 is 120-150kW, which is only used to ensure the power requirements for high-speed driving; the output power of the auxiliary motor 2 is 30-45% of the output power of the main motor 1, preferably 60-80kW, which is used to cooperate with the main motor 1 to output power when the whole machine is operating at low speed.

[0035] The overrunning clutch 3 is used to control the connection or disconnection of the power connection between the auxiliary motor 2 and the main input shaft 411. The speed threshold triggering mechanism of the overrunning clutch 3 automatically locks when the speed of the main input shaft 411 is ≤4500~6000rpm, which corresponds to the speed of the electric construction machinery of 15~20km / h.

[0036] The electric drive system assembly for electric engineering machinery of this utility model has the following working modes:

[0037] (1) Dual motor mode: When a large torque output is required (such as rapid acceleration or hill climbing), the auxiliary motor 2 starts, the overrunning clutch 2 is engaged, and the torque of the auxiliary motor 2 is directly superimposed on the main input shaft 411. It is efficiently combined with the torque of the main motor 1 and input to the driven gear 44, which drives the output shaft 42 to rotate.

[0038] (2) Single motor mode: When only the main motor 1 needs to work (such as during cruise), the auxiliary motor 2 can be stopped or idle (or even act as a generator). At this time, since the speed of the main input shaft 411 (driven by the main motor 1) is higher than the speed of the auxiliary motor 2 (or the direction of the main input shaft 411 is opposite to the direction of the auxiliary input shaft 412), the overrunning clutch 3 automatically overruns (slips), physically disconnecting the power connection between the auxiliary motor 2 and the main input shaft 411, thus avoiding the resistance and energy loss of the auxiliary motor 2.

[0039] This utility model discloses an electric drive system assembly for electric construction machinery. The overrunning clutch is integrated into the input shaft of the reducer, enabling seamless switching between dual-motor and single-motor modes. The transition between the two modes relies on the passive mechanical characteristics of the overrunning clutch (speed difference triggers the overrunning clutch to engage or disengage), requiring no additional electronic control actuator intervention. The switching process is instantaneous, shock-free, and without power interruption, greatly improving driving smoothness and system response speed. It can be applied to electric loaders with a rated load capacity of ≥5 tons, or extended to electric forklifts, electric reach stackers, and electric excavators, among other construction machinery.

[0040] In summary, the electric drive system assembly for electric engineering machinery of this utility model has an extremely simple and compact structure, few parts, and low manufacturing cost. The overrunning clutch is integrated and assembled on the input shaft of the reducer. The mode switching is achieved by relying on the passive mechanical characteristics of the overrunning clutch. It can achieve efficient and seamless coupling and separation of the main and auxiliary motor torques, and significantly improve the smoothness of mode switching while ensuring strong power output.

[0041] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present utility model and are not intended to limit the present utility model. Any changes or modifications to the above embodiments within the scope of the essential spirit of the present utility model will fall within the scope of the claims of the present utility model.

Claims

1. An electric drive system assembly for an electrically powered construction machine, characterized by, A parallel shaft reducer comprising a main motor, an auxiliary motor, and an integrated overrunning clutch, wherein: The parallel shaft reducer has an input shaft and an output shaft. The input shaft includes a main input shaft and an auxiliary input shaft, which are connected by the overrunning clutch. A drive gear is provided on the main input shaft, and a driven gear is provided on the output shaft. The drive gear and the driven gear mesh with each other. The main motor and the auxiliary motor are connected to the main input shaft and the auxiliary input shaft in a one-to-one correspondence; The main motor has an output power of 120-150kW, which is only used to ensure the power requirements for high-speed driving. The output power of the auxiliary motor is 30-45% of the output power of the main motor, and it is used to cooperate with the main motor to output power when the whole machine is operating at low speed. The overrunning clutch is used to control the connection or disconnection of the power connection between the auxiliary motor and the main input shaft.

2. An electric drive system assembly for electrically powered construction machines according to claim 1, characterized in that The output power of the auxiliary motor is 60-80kW.

3. An electric drive system assembly for electrically powered construction machines according to claim 1, characterized in that The overrunning clutch's speed threshold triggering mechanism automatically locks when the input shaft speed is ≤4500~6000rpm, corresponding to a speed of 15~20km / h for electric construction machinery.

4. An electric drive system assembly for electrically powered construction machines according to claim 1, characterized in that When a large torque output is required, the auxiliary motor starts, the overrunning clutch engages, and the torque of the auxiliary motor is directly superimposed on the main input shaft, efficiently merging with the torque of the main motor and inputting together onto the output shaft.

5. An electric drive system assembly for electrically powered construction machines according to claim 1, characterized in that, When only the main motor needs to work, the auxiliary motor stops or idles. When the main input shaft rotates at a speed higher than the auxiliary motor or in the opposite direction to the auxiliary input shaft, the overrunning clutch automatically overruns or slips, disconnecting the power connection between the auxiliary motor and the main input shaft.

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