Comprehensive test system for electric drive axle assembly

Abstract

The invention discloses an assembly test system of an electric drive axle assembly. The test system is composed of an assembly table, an oiling leak hunting table, an oil control table and a comprehensive test table. The assembly table is used for completing assembly overturning of the electric drive axle assembly so as to simulate the posture of the whole axle on the whole vehicle; the leak hunting table is used for filling gas with preset pressure into the inner cavity of the whole bridge and detecting the gas leakage quantity to judge the airtightness of the whole bridge; the comprehensive test board is used for completing differential function detection, ABS function detection, NVH performance detection, electronic parking EPB function detection and P-gear parking EPP function detection of the electric drive axle assembly through one-time clamping; the oil control platform is used for quantitatively filling gear oil into the main reducer cavity of the axle assembly after detection is completed, and the whole axle is turned over to restore the hoisting and transporting posture; and the main control cabinet communicates with the leak hunting table, the comprehensive test table and the oil control table, and is used for coordinating actions of all parts and recording and analyzing test data.

Description

Technical Field

[0001] The present invention belongs to the field of testing for electric drive axle assemblies, and more specifically, it is an integrated testing system for electric drive axle assemblies. Background Art

[0002] With the improvement of environmental protection requirements in recent years and the improvement of electric drive technology and battery technology, new energy vehicles in the market have witnessed a blowout development. Various electric drive technologies have emerged continuously.

[0003] There are structural forms such as converting a traditional vehicle by removing the engine and transmission and replacing them with a central large motor, and there is also a drive mode equipped with in-wheel motors. These technologies have their own advantages and disadvantages. For example, in the case of the conversion from fuel to electricity, except for changing the power system to a large motor, the rest of the traditional system has not changed significantly, resulting in a huge motor volume and low efficiency. For the in-wheel motor solution, each wheel is equipped with a set of motors for independent drive, which brings the convenience of automatic independent control of the motors, but also leads to huge costs.

[0004] Therefore, there has emerged a technical solution for an electric drive axle that integrates a motor and adds a set of reduction systems in the market. This technical solution does not require a large motor and is deeply integrated with the drive axle, which not only simplifies the structure but also controls the cost.

[0005] For electric drive axle manufacturing enterprises, in addition to the differential that comes with the drive axle itself, it also integrates motors, reducer assemblies, etc. These moving parts are concentrated together, which has an impact on the NVH performance of the drive axle. Some electric drive axle products are also equipped with ABS functions, EPB functions, and EPP functions. This requires that when the electric drive axle products leave the production line, these functions need to be detected to ensure that the products meet the functional performance requirements of the vehicle. Summary of the Invention

[0006] The content of the present invention is to design an integrated testing system for electric drive axle assemblies that can perform multi-functional detections in view of the defects existing in the prior art.

[0007] The technical solution of the present invention is as follows: An electric drive axle assembly testing system, characterized by comprising: An assembly table for completing the assembly and flipping of the electric drive axle assembly to simulate the attitude of the entire axle on the vehicle; A leak detection table for filling the inner cavity of the entire axle with gas at a preset pressure and detecting the gas leakage flow rate to determine the airtightness of the entire axle; An integrated testing table for completing the differential function detection, ABS function detection, NVH performance detection, electronic parking brake EPB function detection, and P - gear parking EPP function detection of the electric drive axle assembly through one-time clamping; The oil control platform is used to quantitatively fill the main reduction cavity of the axle assembly with gear oil after the detection is completed, and restore the whole axle to the hoisting and transportation posture by flipping it; The main control cabinet communicates with the leak detection platform, the comprehensive test platform and the oil control platform, and is used to coordinate the actions of each component and record and analyze the test data.

[0008] Furthermore, the assembly platform includes: The flipping mechanism includes a reduction motor, a gearbox, gears, flipping wheels, guide wheels and V-shaped blocks. The reduction motor drives the gears to rotate, transmits the torque to the two-side gearboxes through the drive shaft, drives the flipping wheels to rotate synchronously, and the V-shaped blocks are installed in the flipping wheels to support the workpiece; The handwheel screw mechanism includes a screw handwheel and a guide rail. The flipping mechanism is installed on the base of the assembly platform through the guide rail, and the position of the sliding-end gearbox is adjusted by rotating the screw handwheel to drive the screw, so as to adapt to multi-variety workpieces.

[0009] The leak detection platform (14) is equipped with a leak detector, and the leak detector communicates with the main control cabinet (29), and is used to automatically detect the leakage amount after inflating at a preset pressure, and record and judge the airtightness detection result.

[0010] The assembly platform is used for the assembly preparation of the axle assembly before the assembly test. The oil filling and leak detection platform fills the leak detection oil for the airtightness test of the assembly. The assembly test platform consists of a pneumatic fixture, a base, a loading transmission system, an oil adding / discharging and filtering system, and a test bench control system. The base consists of a tray seat and left and right load output motor seats. The loading transmission system consists of a loading servo motor and a driver, and transmits the power to the coupling, torque limiter, dynamic torque sensor, mechanical main shaft, floating elastic head, and loading shaft loading tooling through a direct connection method. The oil adding / discharging and filtering system consists of an oil adding device and a filtering device. The structure of the oil control platform is a flipping structure, with an oil collection box at the bottom. After the oil is discharged, the flipping table flips the product to the shipping posture and fills the product with oil.

[0011] Furthermore, the comprehensive test platform includes: The base (22) is provided with a workpiece sliding table, and the sliding table is driven by a screw rod to move back and forth to adjust the front and back positions of the workpiece to be tested (15); The loading transmission system includes a servo motor (16), a torque limiter (17), a dynamic torque sensor and a speed output module (18), a mechanical main shaft (19) and a floating bullet head (double diaphragm coupling, 20). The servo motor (16) is installed on the base (22) through a linear guide rail (23), and the sliding table is driven by a screw rod to move left and right, so as to realize the automatic docking / disconnection of the loading shaft and the loading tooling (21) with the workpiece (15). The dynamic torque sensor and the speed output module (18) detect the loading torque and speed, and the torque limiter (17) automatically disconnects when the torque exceeds the limit to protect the sensor; The oil filling / draining and filtering system includes a lubricating oil filling gun (24), a lubricating oil metering filling machine (26) and an oil filling and pumping circulation machine (27), which has the functions of oil filling and pumping. The filter element has an accuracy of ≤10 microns and a built-in heating function to enhance the fluidity of the gear oil; The test bench control system includes a drive-loading system, a logic control system and a data acquisition and analysis system. The drive-loading system adopts a three-motor energy internal circulation mode to realize the test of working conditions such as speed and torque. The logic control system controls the clamping of the tooling, the docking of the workpiece and the safety protection. The data acquisition and analysis system collects data such as vibration and torque in real time and archives and stores them; The operation display system (31) adopts a DTi standard HMI interface, supports Chinese-English switching and multi-authority account management.

[0012] Further defined, the oil control platform includes: The flipping mechanism and the handwheel screw mechanism have the same structure as the assembly table flipping mechanism and the handwheel screw mechanism described in claim 2, and are used to adjust the posture of the workpiece (15); The metering oil filling device includes a lubricating oil filling gun (24) and a lubricating oil metering filling machine (26), which is linked with the oil filling / draining system of the comprehensive test bench, automatically controls the filling amount of the gear oil through the main control cabinet (29), and flips the whole bridge to the shipping state.

[0013] A test method based on the electric drive axle assembly test system described above includes the following steps: Assembly flipping step: Flip the electric drive axle assembly (15) to the simulated vehicle posture through the flipping mechanism of the assembly table, and adjust the position of the flipping mechanism through the handwheel screw mechanism to adapt to the workpiece model; Air tightness detection step: Move the flipped whole bridge to the leak detection table (14), fill the inner cavity with gas at a preset pressure, detect the leakage amount through the leak detector, and the main control cabinet (29) automatically records and judges whether the air tightness is qualified; Multi-functional detection step: Move the qualified whole bridge to the comprehensive test bench, fix it on the base (22) through the workpiece slide table, and perform function detection in sequence through the loading and transmission system after one-time clamping. The dynamic torque sensor and the speed output module (18) monitor the torque and speed in real time, and the sound level sensor and the acceleration sensor monitor the NVH data and feedback it to the main control cabinet (29); Quantitative filling and posture restoration step: After the detection is qualified, move the whole bridge to the oil control platform, fill the main reduction cavity with gear oil through the lubricating oil filling gun (24) and the lubricating oil metering filling machine (26), and then restore the whole bridge to the hoisting and transportation posture through the flipping mechanism; Data processing step: The main control cabinet (29) summarizes the detection data of each step, generates a test report and archives it, and the non-conforming products trigger an alarm and are marked.

[0014] Further defined, in the multi-functional detection step, the drive-loading system of the comprehensive test bench operates in an energy internal circulation mode, and the energy circulation is achieved through three motors-drivers, only supplementing the power grid power loss and friction loss.

[0015] Further defined, for the NVH performance detection, the vibration and noise data are real-time monitored by the sound level sensor and acceleration sensor configured on the comprehensive test bench, and are fed back to the main control cabinet for analysis and processing.

[0016] Beneficial effects: In response to the above-mentioned off-line detection requirements of the electric drive axle, a comprehensive test system including functions such as pre-assembly, flipping, leak detection, etc. is developed, which can detect the leakage level, differential function, NVH performance, ABS function, electronic parking brake EPB function, and P gear parking EPP function of the electric drive axle assembly. Compared with the traditional testing with multiple clamping, multiple lifting, and multiple testing and other cumbersome testing steps, this system integrates these tests into one system, achieving one clamping, one test, and one off-line, improving the testing efficiency. It also avoids the risk of different testing errors caused by multiple clamping. Description of the Drawings

[0017] Figure 1 is the comprehensive test system for the electric drive axle assembly; Figure 2 is the assembly table; Figure 3 is the leak detection table; Figure 4 is the comprehensive test bench; Figure 5 is the oil control table; Figure 6 is the operation display interface of the assembly test bench; Figure 7 is the test result display interface of the assembly test bench.

[0018] Reference numerals in the figures: 1. Assembly table; 2. Leak detection table; 3. Comprehensive test bench; 4. Oil control table; 5. Reduction motor; 6. Gearbox; 7. Flipping wheel; 8. V-block; 9. Guide wheel; 10. Drive shaft; 11. Screw handwheel; 12. Guide rail; 13. Control box; 14. Leak detection table frame; 15. Workpiece to be tested; 16. Servo motor; 17. Torque limiter; 18. Dynamic torque sensor; 19. Mechanical main shaft; 20. Floating bullet head; 21. Loading shaft and loading tooling; 22. Test bench base; 23. Guide rail; 24. Lubricating oil filling gun; 25. Oil barrel; 26. Lubricating oil metering filling machine; 27. Oil injection and pumping circulation machine; 28. Oil pump power station; 29. Control cabinet; 30. Chiller; 31. Operating table; 32. Oil collector. Specific Embodiment

[0019] Embodiment 1

[0020] The test consists of an assembly bench 1, a leak detection bench 2, an oil control bench 4 and a comprehensive test bench 3.

[0021] The assembly platform 1 is composed of a flipping mechanism, a reduction motor 5, a screw mechanism, etc.: the flipping mechanism is composed of gears, a flipping wheel 7, a guide wheel 9, a V-shaped block 8, a cylinder, etc., which can flip the workpiece 90 degrees; the handwheel screw mechanism: composed of a handwheel, a screw, a guide rail 12, a bearing, etc., can move the flipping mechanism to achieve multi-variety compatibility; the ball spline: after moving the flipping mechanism, the workpiece can also be flipped; the reduction motor 5: provides power for flipping. Through the integrated control system, the assembly flipping of the bridge assembly is automatically controlled to simulate the posture of the bridge assembly under the vehicle, in preparation for subsequent tests.

[0022] The leak detection platform 2 is composed of a base, a support base, etc., and the frame is a movable frame protocol. It is equipped with a leak detector, communicates with the main control cabinet, and is operated by the main control console. After inflating according to the specified pressure, the leak detector detects the leakage amount and transmits it to the main control system, and automatically records it, judges whether it is qualified or not, and displays it on the main display screen.

[0023] The comprehensive test bench 3 consists of a base, a loading transmission system, an oil filling and draining and filtering system, and a test bench control system. Through the set program, the leakage level test, differential function, NVH performance, ABS function, electronic parking EPB function and P gear parking EPP function test of the electric drive axle assembly can be completed on the comprehensive test bench 3.

[0024] The test bench base consists of three parts: the tray base, the left and right load output motor bases. The axle has its own motor to drive the axle, the left and right output motors are used for load output, and the two main motors and the corresponding shaft systems are installed on the movable motor base plate. The motor base plate is driven by the servo motor screw to dock with the workpiece and adapt to products of different lengths.

[0025] The loading transmission system consists of a loading servo motor and a driver, which transmits power to the coupling, torque limiter 17, dynamic torque sensor 18, mechanical spindle 19, floating elastic head 20, and loading shaft loading fixture 21 through direct connection. The motor is installed on the slide, and the slide is driven by a screw to move forward and backward, pulling the entire loading unit to move forward and backward, and the loading fixture and the hub assembly are automatically introduced or disengaged; the torque sensor and speed output module can detect the loading torque and rotation speed; the torque limiter can automatically disengage when the actual torque is higher than the limited torque value, protecting the torque sensor and avoiding damage; the mechanical spindle 19 adopts a high-precision spindle with the characteristics of low noise, low vibration, and low energy loss. It plays the role of a slewing support between the docking loading fixture and the torque sensor, while resisting the axial impact force of the drive, protecting the torque sensor, and enhancing the rigidity of the drive rotation system; After the feed slide is in place, there are automatic braking and locking measures to ensure that the slide support plate does not vibrate during the test and eliminate the impact on the test process; floating elastic head 20 (double diaphragm coupling): it has elasticity and floating amount, and when the center of the loading shaft is concentric with the output end of the workpiece, it plays a role in adjusting the concentricity and deflection to avoid the impact of the non-concentricity on the detection process; loading shaft and loading tooling 21: it is a loaded force-bearing part, which bears the loading torque. The tooling head (loading head) is an elastic structure, and the loading shaft rotates slowly. When the tooling head is not introduced, the spring is compressed. As the rotation progresses, the spring extends, and the tooling head automatically docks with the end face of the hub and the wheel bolts.

[0026] The oil filling and filtering system consists of a refueling device and a filtering device. The refueling device automatically controls the refueling amount through a quantitative filling machine. The oil filter has the functions of oil filling and oil extraction, and the filter element has an accuracy of 10 microns. The oil filter has a built-in heating function to enhance the fluidity of the gear oil.

[0027] The test bench control system consists of a drive-loading system, a logic control system, a data acquisition and analysis system, a control cabinet, a power supply system, a signal transmission system, an operation display system, a work monitoring system, etc.

[0028] Drive-loading system: 1 set of driver for the motor of the tested object, 2 sets of load motors and drivers. Realize the working conditions required for the test (speed, torque, acceleration, acceleration-forward drag, coasting-reverse drag, etc.). The three motors work in the energy internal circulation mode, most of the energy circulates in the three motors-drivers, and the power grid only needs to supplement the power loss and friction loss (about 10% of the power of the test condition). The capacity of the two wheel-end motors is: rated 1000RPM, 200Nm.

[0029] Logical control system: responsible for the clamping of tooling, workpiece docking, motor control, and other error prevention, safety protection and other functions during the entire bench test process.

[0030] Data acquisition and analysis system: Execute the test program, perform real-time acquisition and analysis of data such as vibration, torque, and rotational speed, and archive and save the test results, etc.

[0031] Control cabinet: It includes the main control and drive cabinet and the computer cabinet. The main control cabinet 29 contains a PLC, a main power switch, an emergency stop system, a power distribution system, and a driver for the small servo motor. The computer cabinet includes a computer, a data acquisition card, a screen, a UPS power supply, a conditioning circuit for sensors, and the HMI of the PLC.

[0032] The power supply system includes a control unit, a rectifier / regenerative module, a drive module, and a braking resistor. The drive modules of this system share a DC power supply module, which can achieve the function of energy recycling, better save energy, and the large capacity of the driver is adapted to the motor.

[0033] Signal transmission includes Ethernet communication among the PLC, IO module, driver, and PC, with a fast transmission rate, which can more precisely control the servo motor.

[0034] The operation display system adopts the standard HMI interface of DTi, with the display language being Chinese and English and being switchable. The interface can display the test result content, the total number of tests, the number of qualified and unqualified tests, etc. as required. And it can modify the test parameters with permissions. There are dedicated permission accounts for operators, maintenance personnel, process engineers, etc.

[0035] The working monitoring system uses a PLC to control and monitor the speed and torque (test conditions) of the bench motor and the motor under test, the fixture actions, the system safety, the cooling system, and coordinates the test computer and the production line.

[0036] During the test, install a sound level sensor and an acceleration sensor at the appropriate positions according to different products, connect them to the control cabinet, and the test results can be automatically processed, displayed, and recorded.

[0037] The structure of the oil control table 4 is similar to that of the assembly table 1, with an additional oil collection device.

[0038] One Equipment Overview 1.1 Total Weight 13.5T 1.2 Floor Area 13500mm X 4200mm 1.3 Air Pressure (gas source provided by the buyer) ≥0.6Mpa 1.4 Hydraulic Pressure (with built-in hydraulic station) 0 - 10Mpa 1.6 Power Supply Three-phase 380V, 500A Two Output End Part 2.1 Maximum Motor Speed 2000rpm 2.2 Rated Motor Torque 210Nm 2.3 Adjustable Range of the Motor Front and Rear 0 - 700mm 2.4 Test Range of Torque Sensor 0 - 500n.m 2.5 Accuracy of Torque and Acceleration Sensors ±0.5% 2.6 Positioning Accuracy of Lead Screw Motor 0.01mm / 300mm Three Fixture Part 3.1 Repeatability Positioning Accuracy ≤0.05mm Four Repeatability and Correlation of Equipment Test Results 4.1 Repeatability ±3dB 4.2 Correlation ≥0.8 。

Claims

1. An electric drive axle assembly test system, characterized in that, Including: An assembly table for completing the assembly and flipping of the electric drive axle assembly (15) to simulate the attitude of the complete axle on the vehicle; A leak detection table (14) for filling the inner cavity of the complete axle with gas at a preset pressure and detecting the gas leakage flow rate to judge the airtightness of the complete axle; A comprehensive test table for completing the differential function detection, ABS function detection, NVH performance detection, electronic parking EPB function detection, and P gear parking EPP function detection of the electric drive axle assembly (15) through one clamping; An oil control table for quantitatively filling gear oil into the main reduction cavity of the axle assembly after the detection is completed and restoring the complete axle to its hoisting and transportation attitude by flipping it; A main control cabinet (29) communicating with the leak detection table (14), the comprehensive test table, and the oil control table for coordinating the actions of each component and recording and analyzing the test data.

2. The electric drive axle assembly test system according to claim 1, wherein The assembly table includes: A flipping mechanism including a reduction motor (5), a gearbox (6), gears, flipping wheels (7), guide wheels (9), and V-shaped blocks (8). The reduction motor (5) drives the gears to rotate, transmits the torque to the two-side gearboxes (6) through a drive shaft (10), drives the flipping wheels (7) to rotate synchronously, and the V-shaped blocks (8) are installed in the flipping wheels (7) to support the workpiece (15); A handwheel screw mechanism including a screw handwheel (11) and a guide rail (12). The flipping mechanism is installed on the base of the assembly table through the guide rail (12), and the position of the sliding-end gearbox (6) is adjusted by rotating the screw handwheel (11) to drive the screw, so as to adapt to workpieces (15) of multiple varieties.

3. The electric drive axle assembly test system according to claim 1, characterized in that The leak detection table (14) is equipped with a leak detector, which communicates with the main control cabinet (29) for automatically detecting the leakage amount after inflating at a preset pressure and recording and judging the airtightness detection result.

4. The electric drive axle assembly test system according to claim 1, characterized in that, The comprehensive test table includes: A base (22) provided with a workpiece sliding table, and the front and rear positions of the workpiece to be tested (15) are adjusted by driving the sliding table to move back and forth through a lead screw; A loading transmission system including a servo motor (16), a torque limiter (17), a dynamic torque sensor and a speed output module (18), a mechanical main shaft (19), and a floating bullet head (double diaphragm coupling, 20). The servo motor (16) is installed on the base (22) through a linear guide rail (23), and the sliding table is driven to move left and right through a lead screw to realize the automatic docking / disconnection of the loading shaft and the loading tooling (21) and the workpiece (15). The dynamic torque sensor and the speed output module (18) detect the loading torque and speed, and the torque limiter (17) automatically disconnects when the torque exceeds the limit to protect the sensor; An oil adding / discharging and filtering system including a lubricating oil filling gun (24), a lubricating oil quantitative filling machine (26), and an oil filling and pumping circulation machine (27), which has the functions of oil filling and pumping, the filter element accuracy ≤ 10 microns, and has a self-heating function to enhance the fluidity of the gear oil. The test bench control system includes a drive-loading system, a logic control system, and a data acquisition and analysis system. The drive-loading system adopts a three-motor energy internal circulation mode to achieve working condition tests such as speed and torque. The logic control system controls tooling clamping, workpiece docking, and safety protection. The data acquisition and analysis system real-time collects data such as vibration and torque and archives and stores them. The operation display system (31) adopts a DTi standard HMI interface, supports Chinese-English switching and multi-authority account management.

5. The electric drive axle assembly test system according to claim 1, wherein The oil control table includes: The flipping mechanism and the handwheel screw mechanism, which have the same structure as the flipping mechanism and the handwheel screw mechanism of the assembly table described in claim 2, are used to adjust the posture of the workpiece (15). The quantitative oil filling device includes a lubricating oil filling gun (24) and a lubricating oil quantitative filling machine (26), which are linked with the oil adding and discharging system of the comprehensive test bench. The main control cabinet (29) automatically controls the filling amount of gear oil and flips the whole bridge to the shipping state.

6. A testing method for the testing system of the electric drive axle assembly according to any one of claims 1-5, characterized in that, It includes the following steps: Assembly flipping step: Flip the electric drive axle assembly (15) to the simulated vehicle posture through the flipping mechanism of the assembly table, and adjust the position of the flipping mechanism through the handwheel screw mechanism to adapt to the workpiece model. Air tightness detection step: Transfer the flipped whole bridge to the leak detection table (14), fill the inner cavity with gas at a preset pressure, detect the leakage amount through a leak detector, and the main control cabinet (29) automatically records and judges whether the air tightness is qualified. Multi-functional detection step: Transfer the qualified whole bridge to the comprehensive test bench, fix it on the base (22) through the workpiece sliding table, and perform function detections in sequence through the loading and transmission system after one-time clamping. The dynamic torque sensor and the speed output module (18) real-time monitor the torque and speed, and the sound level sensor and the acceleration sensor monitor the NVH data and feedback it to the main control cabinet (29). Quantitative filling and posture restoration step: After the detection is qualified, transfer the whole bridge to the oil control table, fill the main reduction cavity with gear oil through the lubricating oil filling gun (24) and the lubricating oil quantitative filling machine (26), and then restore the whole bridge to the hoisting and transportation posture through the flipping mechanism. Data processing step: The main control cabinet (29) summarizes the detection data of each step, generates a test report and archives it, and the unqualified products trigger an alarm and are marked.

7. The test method according to claim 6, wherein In the multi-functional detection step, the drive-loading system of the comprehensive test bench works in an energy internal circulation mode, and the energy circulation is realized through three motors - drivers, only supplementing the power grid power loss and friction loss.

8. The test method according to claim 6, wherein The NVH performance detection real-time monitors the vibration and noise data through the sound level sensor and the acceleration sensor configured on the comprehensive test bench, and feedbacks it to the main control cabinet for analysis and processing.

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