Method for detecting a wet dual-clutch automatic transmission

Abstract

The application discloses a wet type double-clutch automatic gearbox offline detection method, which comprises the following steps: input and output detection: detecting whether the value of each sensor is within the range of the set maximum value and minimum value; current control detection; PRND calibration: giving the input shaft of the automatic gearbox to be detected a rotating speed of N1 r / min, and detecting the voltage of the PRND position sensor when the shift handle is in P, R, N and D positions respectively; when the detected voltage of P, R, N and D positions is within the range of the set maximum value and minimum value of the corresponding position, the PRND calibration is passed, otherwise, the PRND calibration fails; clutch leakage detection; hydraulic leakage detection one; shift fork calibration; hydraulic leakage detection two; clutch pressure current detection; half combination point detection; shift quality detection. The application has the advantages of accuracy, convenience and reliability in the detection of the automatic gearbox.

Description

Technical Field

[0001] This invention relates to the field of automatic transmission testing, specifically to a method for testing wet dual-clutch automatic transmissions before they leave the production line. Background Technology

[0002] With the increasingly widespread application of automatic transmissions, ensuring their quality and performance is becoming increasingly important. Off-line testing of automatic transmissions plays a crucial role as a checkpoint before they leave the factory and enter the market.

[0003] Substandard automatic transmissions have entered the market, posing safety risks to consumers; automatic transmissions lacking basic characteristic data, or with inaccurate basic characteristic data, have resulted in extremely poor driving and riding experiences; manual and unmanaged off-line inspection methods cannot meet the rapid testing needs of large-scale automatic transmissions; when off-line inspections fail, the problem cannot be quickly located, and finding the cause is time-consuming and laborious. These and other similar issues related to the off-line inspection of automatic transmissions persist and require our concerted efforts to overcome and resolve. Summary of the Invention

[0004] This invention provides a method for testing wet dual-clutch automatic transmissions before they leave the production line. This invention offers a fast, accurate, convenient and reliable testing solution for the production, delivery and market launch of automatic transmissions.

[0005] The technical solutions to the above technical problems are as follows:

[0006] A method for off-line testing of a wet dual-clutch automatic transmission, characterized by comprising:

[0007] The steps for input / output detection are: checking whether the values ​​of each sensor are within their respective set maximum and minimum ranges, and whether each sensor reports a fault;

[0008] The steps of current-controlled detection;

[0009] The steps for PRND calibration are as follows: Apply a rotational speed of N1 rpm to the input shaft of the automatic transmission to be tested, and detect the voltage of the PRND position sensor when the shift lever is in the P, R, N, and D positions respectively. If the detected voltages at the P, R, N, and D positions are all within the range of the set maximum and minimum values ​​for their respective positions, then the PRND calibration is successful; otherwise, the PRND calibration fails.

[0010] The steps for clutch leakage detection, hydraulic leakage detection step one; shift fork calibration steps; hydraulic leakage detection step two; clutch pressure and current detection steps; half-engagement point detection steps; and shift quality detection steps.

[0011] Furthermore, in the input / output detection step, the input shaft of the automatic transmission under test is first given a speed of N2 rpm. Then, the values ​​of the shift fork position sensor, clutch pressure sensor, clutch outlet temperature sensor, transmission oil temperature sensor, PRND position sensor, input shaft speed sensor, output shaft speed sensor, output shaft direction sensor, key position sensor, and PCB temperature sensor are checked to see if they are within the range of their respective set maximum and minimum values. Additionally, the values ​​of the shift fork position sensor, clutch pressure sensor, clutch outlet temperature sensor, transmission oil temperature sensor, PRND position sensor, input shaft speed sensor, output shaft speed sensor, main pressure solenoid valve, lubrication solenoid valve, clutch pressure solenoid valve, shift fork shifting solenoid valve, shift fork reversing solenoid valve, and 5V and 8V power supply voltage sensors are checked to see if any faults are reported. If the values ​​of all the above sensors and solenoid valves are within their respective set maximum and minimum values, and no faults are reported by the sensors or solenoid valves, then the input / output detection passes; otherwise, the input / output detection fails.

[0012] Further, the current control detection step includes: applying a rotational speed of N3 rpm to the input shaft of the automatic transmission to be tested, applying control currents of different values ​​within the input current range of several solenoid valves to the main pressure solenoid valve, lubrication solenoid valve, shift fork shifting solenoid valve, clutch solenoid valve, and shift fork reversing solenoid valve respectively, reading the feedback current after each control current is applied to each of the above solenoid valves, and comparing each control current of each of the above solenoid valves and its corresponding feedback current. When the difference after comparison is less than or equal to the maximum allowable deviation value set by each valve, the current control detection passes; otherwise, the current control detection fails.

[0013] Furthermore, the clutch leakage detection steps are as follows: the input shaft of the automatic transmission to be tested is given a speed of N4 rpm, the main pressure of the transmission is brought to its maximum value through computer control commands, and the actual clutch pressure value is detected when the current is applied to the clutch.

[0014] When the minimum value of the clutch input current range is applied, the corresponding actual clutch pressure value is less than or equal to the set maximum value pressure at low pressure, and when the maximum value of the clutch input current range is applied, the corresponding actual clutch pressure value is greater than or equal to the set minimum value pressure at high pressure, then the clutch leakage detection passes; otherwise, the clutch leakage detection fails.

[0015] Further, the hydraulic leakage detection step one is as follows: when the transmission oil temperature is Y1, the main pressure of the transmission is brought to the maximum value through computer control command, the maximum current of the clutch input current range is applied to the clutch, the input shaft of the automatic transmission to be tested is given several different speeds, and the actual clutch pressure value at each input shaft speed is detected.

[0016] When the actual clutch pressure value detected at the corresponding input shaft speed is greater than or equal to the set minimum pressure value at the corresponding input shaft speed for all the above input shaft speeds, the hydraulic leakage detection passes; otherwise, the hydraulic leakage detection fails.

[0017] Further, the shift fork calibration steps are as follows: The input shaft of the automatic transmission to be tested is given a speed of N5 rpm; the main pressure of the transmission is brought to its maximum value via computer control commands; the left gear, neutral, and right gear positions on each shift fork are self-learned by controlling the shift fork engagement solenoid valve and the shift fork reversing solenoid valve, obtaining the gear positions of the left gear, neutral, and right gear positions on all shift forks. The shift fork calibration test passes when the following conditions are met simultaneously:

[0018] 1) The difference between the neutral position on each shift fork and the left gear position on the same shift fork is within the set maximum and minimum range, and the difference between the neutral position on each shift fork and the right gear position on the same shift fork is within the set maximum and minimum range.

[0019] 2) The deviation of the neutral position on the same shift fork during multiple self-learning processes is less than or equal to the set maximum value of the neutral deviation;

[0020] 3) For each non-neutral gear, the deviation of the gear position during multiple self-learning sessions is less than or equal to the set maximum deviation for non-neutral gears;

[0021] 4) The left-hand position on each shift fork is within the set maximum and minimum value range;

[0022] 5) The right-hand position of each shift fork is within the set maximum and minimum value range;

[0023] If the above 5 conditions cannot be met simultaneously, the shift fork calibration test will fail.

[0024] Further, the steps of the second hydraulic leakage detection are as follows: When the transmission oil temperature is Y2, the main pressure of the transmission is brought to its maximum value through computer control commands, the maximum current of the clutch input current range is applied to the clutch, and the input shaft of the automatic transmission to be tested is given several different speeds. The actual clutch pressure value at each input shaft speed is detected. When the actual clutch pressure value detected at the corresponding input shaft speed is greater than or equal to the set minimum pressure value at the corresponding input shaft speed, the second hydraulic leakage detection passes; otherwise, the second hydraulic leakage detection fails.

[0025] Further, the steps for clutch pressure current detection are as follows: The input shaft of the automatic transmission under test is given a speed of N6 rpm. The main pressure of the transmission is brought to its maximum value via computer control commands. Several control currents with different values ​​within the range of the clutch solenoid valve's input current are applied to the clutch solenoid valve. The actual clutch pressure value after each control current is applied is detected. The clutch pressure current detection passes when the following conditions are met simultaneously:

[0026] 1) The actual clutch pressure value at each control current, within the maximum and minimum pressure range set for the corresponding current value;

[0027] 2) The maximum fluctuation of the actual clutch pressure value at each control current is less than or equal to the maximum fluctuation pressure value set at the corresponding current value.

[0028] 3) When the control current is increasing, the corresponding actual clutch pressure value is also increasing, and the increment of the actual clutch pressure value is greater than or equal to the set minimum increment pressure value.

[0029] If the above three conditions cannot be met simultaneously, the clutch pressure current detection will fail.

[0030] Furthermore, the steps for half-engagement point detection are as follows: the input shaft of the automatic transmission to be tested is given a speed of N7 rpm, the main pressure of the transmission is brought to its maximum value through computer control commands, the clutch half-engagement point is self-learned by controlling the clutch solenoid valve to obtain the clutch half-engagement point position, and the half-engagement point detection is passed when the clutch half-engagement point pressure is within the set maximum and minimum value range; otherwise, the half-engagement point detection fails.

[0031] Furthermore, the shift quality test steps are as follows: The input shaft of the automatic transmission under test is given a speed of N8 rpm. The main pressure of the transmission is brought to its maximum value via computer control commands. The shift fork engagement solenoid valve and shift fork reversing solenoid valve are controlled to engage each non-neutral gear. The synchronization time and shift time of each shift fork engagement are detected. The shift quality test passes when the synchronization time of all shift forks is less than or equal to the set maximum synchronization time, and the shift time is less than or equal to the set maximum shift time; otherwise, the shift quality test fails.

[0032] This invention proposes a series of testing items, provides specific testing methods for each item, and arranges these testing items into reasonable testing steps, thereby achieving fast, accurate, convenient and reliable off-line testing of wet dual-clutch automatic transmissions.

[0033] The present invention has the following beneficial effects: it can not only detect whether the wet dual-clutch automatic transmission is qualified, but also obtain the basic characteristic data of the automatic transmission. It can also greatly automate the off-line inspection process, reduce labor intensity and improve off-line inspection efficiency, and lay a solid foundation for the normal operation of the automatic transmission in the whole vehicle. Attached Figure Description

[0034] Figure 1 A flowchart of the wet dual-clutch automatic transmission off-line testing method provided in an embodiment of the present invention. Detailed Implementation

[0035] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0036] Figure 1 The flowchart below illustrates a method for detecting a wet dual-clutch automatic transmission after it has been manufactured, according to an embodiment of the present invention. This method includes the following steps: detection preparation, input / output detection, current control detection, PRND calibration, clutch leakage detection, hydraulic leakage detection one, shift fork calibration, hydraulic leakage detection two, clutch pressure and current detection, partial engagement point detection, shift quality detection, exporting detection data, generating a detection report, and saving the detection process data. The following provides a detailed explanation of each step:

[0037] S1, the test preparation steps are as follows: install the automatic transmission to be tested on a test bench that can provide an adjustable speed to the input shaft of the automatic transmission to be tested, connect the transmission to the computer through a wiring harness, power on the transmission control unit, establish a test control communication connection between the computer and the transmission control unit, ensure that the shift lever is in the N position, all shift forks are in the neutral position and both clutches are in the fully open state, input the project number, transmission number and clutch number of the automatic transmission to be tested, and import the hydraulic module number, pressure-current and flow-current correspondence data into the computer.

[0038] S2, the input / output detection steps are as follows: The input shaft of the automatic transmission under test is given a speed of 0 rpm via a test bench. Through control and coordination between the computer and the transmission control unit, the values ​​of the shift fork position sensor, clutch pressure sensor, clutch outlet temperature sensor, transmission oil temperature sensor, PRND position sensor, input shaft speed sensor, output shaft speed sensor, output shaft direction sensor, key position sensor, and PCB temperature sensor are checked to see if they are within the maximum and minimum value ranges set by the respective sensors. Additionally, the system checks for fault reports from the shift fork position sensor, clutch pressure sensor, clutch outlet temperature sensor, transmission oil temperature sensor, PRND position sensor, input shaft speed sensor, output shaft speed sensor, main pressure solenoid valve, lubrication solenoid valve, clutch pressure solenoid valve, shift fork shifting solenoid valve, shift fork reversing solenoid valve, and the 5V and 8V power supply voltage sensors. If the values ​​of these sensors and solenoid valves are within their respective maximum and minimum value ranges, and no fault reports are found, the input / output detection passes; otherwise, the input / output detection fails.

[0039] S3, the current control detection steps are as follows: The input shaft of the automatic transmission under test is subjected to a speed of 0 rpm via a test bench. Control currents of different values ​​within the input current range of several solenoid valves are applied to the main pressure solenoid valve, lubrication solenoid valve, shift fork engagement solenoid valve, clutch solenoid valve, and shift fork reversing solenoid valve. The feedback current after applying each control current to each solenoid valve is read, and each control current and its corresponding feedback current are compared. If the difference between the compared values ​​is less than or equal to the maximum allowable deviation set for each valve, the current control detection passes; otherwise, the current control detection fails. For example, the input current range of the lubrication solenoid valve is 0 mA to 1200 mA. Control currents of 0 mA, 200 mA, 400 mA, 600 mA, 800 mA, 1000 mA, and 1200 mA are applied to the lubrication solenoid valve, and the feedback current after applying each control current is read. If the absolute value of the difference between the control current and the feedback current at each of the following points (0 mA, 200 mA, 400 mA, 600 mA, 800 mA, 1000 mA, and 1200 mA) is less than or equal to the maximum allowable deviation of 10 mA set for the lubrication solenoid valve, then the current control test of the lubrication solenoid valve passes; otherwise, the current control test of the lubrication solenoid valve fails. This step is considered successful only if the current control test of all solenoid valves passes. In this step, the feedback current used for calculation is the average value after multiple samplings. The processing of voltage and pressure values ​​in the following steps is similar and will not be repeated hereafter.

[0040] S4, the PRND calibration steps are as follows: The input shaft of the automatic transmission under test is subjected to a speed of 0 rpm using a test bench, and the voltage of the PRND position sensor is detected when the shift lever is in the P, R, N, and D positions respectively. If the detected voltages at the P, R, N, and D positions are all within the set maximum and minimum values ​​for their respective positions, the PRND calibration is successful; otherwise, the PRND calibration fails.

[0041] S5, the clutch leakage detection steps are as follows: The input shaft of the automatic transmission under test is subjected to a speed of 1000 rpm via a testing bench. Computer control commands are used to maximize the main pressure of the transmission. The actual clutch pressure value is detected when the clutch input current is applied. If the actual clutch pressure value is less than or equal to the set maximum pressure at low pressure (e.g., 50 cbar) when the minimum current in the clutch input current range is applied, and the actual clutch pressure value is greater than or equal to the set minimum pressure at high pressure (e.g., 1800 cbar), then the clutch leakage detection passes; otherwise, the clutch leakage detection fails.

[0042] S6, the steps of hydraulic leak detection one are as follows: When the transmission oil temperature is 30 degrees Celsius, the main pressure of the transmission is brought to its maximum value via computer control commands. The maximum value of the clutch input current range is applied to the clutch. The input shaft of the automatic transmission under test is subjected to several different speeds (e.g., 600 rpm, 800 rpm, 1200 rpm) via a testing bench. The actual clutch pressure value at each input shaft speed is detected. When the actual clutch pressure value detected at the corresponding input shaft speed is greater than or equal to the set minimum pressure value for the corresponding input shaft speed (e.g., 1300 cbar, 1700 cbar, 1800 cbar), the hydraulic leak detection one pass; otherwise, the hydraulic leak detection one fails.

[0043] S7, the shift fork calibration steps are as follows: The input shaft of the automatic transmission under test is subjected to a speed of 1000 rpm via a test bench. Computer control commands are used to maximize the main pressure of the transmission. The shift fork engagement solenoid valve and shift fork reversing solenoid valve are controlled to perform self-learning on the left-hand gear (e.g., the gear with lower voltage at the shift fork position), neutral, and right-hand gear (e.g., the gear with higher voltage at the shift fork position) on each shift fork, obtaining the gear positions of the left-hand, neutral, and right-hand gears on all shift forks. The shift fork calibration test passes when the following conditions are simultaneously met:

[0044] 1) The difference between the neutral position on each shift fork and the left gear position on the same shift fork is within the set maximum and minimum range, and the difference between the neutral position on each shift fork and the right gear position on the same shift fork is within the set maximum and minimum range.

[0045] 2) The deviation of the neutral position on the same shift fork during multiple self-learning processes is less than or equal to the set maximum value of the neutral deviation;

[0046] 3) For each non-neutral gear, the deviation of the gear position during multiple self-learning sessions is less than or equal to the set maximum deviation for non-neutral gears;

[0047] 4) The left-hand position on each shift fork is within the set maximum and minimum value range;

[0048] 5) The right-hand position on each shift fork is within the set maximum and minimum value range.

[0049] If the above 5 conditions cannot be met simultaneously, the shift fork calibration test will fail.

[0050] S8, the steps for hydraulic leak detection step two are as follows: When the transmission oil temperature is 60 degrees Celsius, the main pressure of the transmission is brought to its maximum value via computer control commands. The maximum current within the clutch input current range is applied to the clutch. The input shaft of the automatic transmission under test is subjected to several different speeds via a testing bench, and the actual clutch pressure value at each input shaft speed is detected. If the actual clutch pressure value detected at the corresponding input shaft speed is greater than or equal to the set minimum pressure value for that input shaft speed, the hydraulic leak detection step two passes; otherwise, it fails.

[0051] S9, the steps for clutch pressure current detection are as follows: The input shaft of the automatic transmission under test is subjected to a speed of 1000 rpm via a testing bench. Computer control commands are used to maximize the main pressure of the transmission. Several control currents with different values ​​within the clutch solenoid valve input current range are applied to the clutch solenoid valve. The actual clutch pressure value after each control current is applied is detected. The clutch pressure current detection passes when the following conditions are met simultaneously:

[0052] 1) The actual clutch pressure value at each control current, within the maximum and minimum pressure range set for the corresponding current value;

[0053] 2) The maximum fluctuation of the actual clutch pressure value at each control current is less than or equal to the maximum fluctuation pressure value set at the corresponding current value.

[0054] 3) When the control current is increasing, the corresponding actual clutch pressure value is also increasing, and the increment of the actual clutch pressure value is greater than or equal to the set minimum increment pressure value.

[0055] If the above three conditions cannot be met simultaneously, the clutch pressure current detection will fail.

[0056] S10, the steps for the partial engagement point detection include: applying a speed of 1000 rpm to the input shaft of the automatic transmission under test via a test bench; using computer control commands to maximize the main pressure of the transmission; and controlling the clutch solenoid valve to perform self-learning on the clutch partial engagement point to obtain its position. The partial engagement point detection passes when the clutch partial engagement point pressure is within the set maximum and minimum value range; otherwise, it fails.

[0057] S11, the shift quality test steps include: applying a speed of 1000 rpm to the input shaft of the automatic transmission under test using a test bench; using computer control commands to maximize the main pressure of the transmission; controlling the shift fork engagement solenoid valve and shift fork reversing solenoid valve to engage each non-neutral gear; and testing the synchronization time and shift time of each shift fork engagement. The shift quality test passes when the synchronization time of all shift fork engagements is less than or equal to the set maximum synchronization time, and the shift time is less than or equal to the set maximum shift time; otherwise, the shift quality test fails.

[0058] S12, the step of exporting the test data includes: when all the above test steps have passed, exporting all the basic characteristic data of the transmission obtained from the test into a newly created DCM format file. For example, the file may include the following information:

[0059] 1) System Information: Project Number, Gearbox Number, Hydraulic Module Number, Clutch Number, Inspection Date and Time, Inspector;

[0060] 2) Positions of P, R, N, and D;

[0061] 3) The positions of each gear on the shift fork;

[0062] 4) Pressure-current relationship of main pressure solenoid valve, flow-current relationship of lubrication solenoid valve, pressure-current relationship of shift fork shifting solenoid valve;

[0063] 5) The pressure-current relationship of the clutch;

[0064] 6) The pressure-torque relationship of the clutch;

[0065] 7) The position of the clutch half-engagement point.

[0066] S13, the steps for generating the test report are as follows: During the above-mentioned wet dual-clutch automatic transmission off-line testing process, an HTML format test report file can be generated at any time as needed to view the status, time taken, test data, and test standards of all the above-mentioned test steps. For example, the test report file can include the following information in tabular form:

[0067] 1) Overview Information

[0068] The serial number of the automatic transmission to be inspected, the date and time of inspection, the inspector, and whether the inspection passed, etc.;

[0069] 2) Detailed information for each testing step

[0070] The name of the testing step, whether the test passed or failed, the testing duration, the testing data, the testing standards, etc.

[0071] In addition, during all the above testing steps, help information, testing progress information, whether the test passed or failed, testing data and testing standards will be displayed in real time. Moreover, all these prompts will not affect the pace and efficiency of offline testing.

[0072] S14, the steps for saving the test process data are as follows: the entire process data of the above wet dual-clutch automatic transmission off-line test will be recorded and saved in ETASMDF format for analysis and archiving.

[0073] The method of this invention is applicable to the field of automatic transmission testing. Using this invention, not only can the quality of wet dual-clutch automatic transmissions be detected, but basic characteristic data of the automatic transmission can also be obtained. Furthermore, it can greatly automate the off-line testing process, reduce labor intensity, and improve off-line testing efficiency, laying a solid foundation for the normal operation of the automatic transmission in the vehicle.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for detecting the off-line operation of a wet dual-clutch automatic transmission, characterized in that, include: The steps for input / output detection are: checking whether the values ​​of each sensor are within their respective set maximum and minimum values, and whether each sensor reports a fault; The steps of current control detection include: applying a speed of N3 rpm to the input shaft of the automatic transmission under test; applying control currents of different values ​​within the input current range of several solenoid valves to the main pressure solenoid valve, lubrication solenoid valve, shift fork shifting solenoid valve, clutch solenoid valve, and shift fork reversing solenoid valve; reading the feedback current after applying each control current to each solenoid valve; and comparing each control current of each solenoid valve with its corresponding feedback current. If the difference after comparison is less than or equal to the maximum allowable deviation set by each valve, the current control detection passes; otherwise, the current control detection fails. The steps for PRND calibration are as follows: Apply a rotational speed of N1 rpm to the input shaft of the automatic transmission to be tested, and detect the voltage of the PRND position sensor when the shift lever is in the P, R, N, and D positions respectively. If the detected voltages at the P, R, N, and D positions are all within the range of the set maximum and minimum values ​​for their respective positions, then the PRND calibration is successful; otherwise, the PRND calibration fails. The steps for clutch leakage detection, hydraulic leakage detection step one; shift fork calibration steps; hydraulic leakage detection step two; clutch pressure and current detection steps; half-engagement point detection steps; shift quality detection steps. The steps of the hydraulic leakage detection are as follows: when the transmission oil temperature is Y1, the main pressure of the transmission is brought to the maximum value through computer control commands, the maximum current of the clutch input current range is applied to the clutch, the input shaft of the automatic transmission to be tested is given several different speeds, and the actual clutch pressure value at each input shaft speed is detected. When the actual clutch pressure value detected at the corresponding input shaft speed is greater than or equal to the set minimum pressure value at the corresponding input shaft speed for all of the above input shaft speeds, the hydraulic leakage detection passes; otherwise, the hydraulic leakage detection fails. The shift fork calibration steps are as follows: The input shaft of the automatic transmission to be tested is given a speed of N5 rpm. The main pressure of the transmission is brought to its maximum value via computer control commands. The left, neutral, and right gear positions on each shift fork are self-learned by controlling the shift fork engagement solenoid valve and the shift fork reversing solenoid valve, thus obtaining the gear positions of the left, neutral, and right gear positions on all shift forks. The shift fork calibration test passes when the following conditions are simultaneously met: 1) The difference between the neutral position on each shift fork and the left gear position on the same shift fork is within the set maximum and minimum range, and the difference between the neutral position on each shift fork and the right gear position on the same shift fork is within the set maximum and minimum range. 2) The deviation of the neutral position on the same shift fork during multiple self-learning processes is less than or equal to the set maximum value of the neutral deviation. 3) For each non-neutral gear, the deviation of the gear position during multiple self-learning sessions is less than or equal to the set maximum deviation for non-neutral gears; 4) The left-hand position on each shift fork is within the set maximum and minimum value range; 5) The right-hand position of each shift fork is within the set maximum and minimum value range; If the above 5 conditions cannot be met at the same time, the shift fork calibration test will fail. The shift quality test steps are as follows: The input shaft of the automatic transmission under test is given a speed of N8 rpm. The main pressure of the transmission is brought to its maximum value via computer control commands. The shift fork engagement solenoid valve and shift fork reversing solenoid valve are controlled to engage each non-neutral gear. The synchronization time and shift time of each shift fork engagement are detected. The shift quality test passes when the synchronization time of all shift forks is less than or equal to the set maximum synchronization time, and the shift time is less than or equal to the set maximum shift time; otherwise, the shift quality test fails.

2. The method for detecting the off-line operation of a wet dual-clutch automatic transmission according to claim 1, characterized in that, In the input / output detection step, the input shaft of the automatic transmission under test is first given a speed of N2 rpm. Then, the values ​​of the shift fork position sensor, clutch pressure sensor, clutch outlet temperature sensor, transmission oil temperature sensor, PRND position sensor, input shaft speed sensor, output shaft speed sensor, output shaft direction sensor, key position sensor, and PCB temperature sensor are checked to see if they are within the range of their respective set maximum and minimum values. Additionally, the values ​​of the shift fork position sensor, clutch pressure sensor, clutch outlet temperature sensor, transmission oil temperature sensor, PRND position sensor, input shaft speed sensor, output shaft speed sensor, main pressure solenoid valve, lubrication solenoid valve, clutch pressure solenoid valve, shift fork shifting solenoid valve, shift fork reversing solenoid valve, 5V, and 8V power supply voltage sensors are checked to see if any faults are reported. If the values ​​of all the above sensors and solenoid valves are within their respective set maximum and minimum values, and no faults are reported by the sensors or solenoid valves, the input / output detection passes; otherwise, the input / output detection fails.

3. The method for detecting the off-line operation of a wet dual-clutch automatic transmission according to claim 1, characterized in that, The steps for clutch leakage detection are as follows: apply a rotational speed of N4 rpm to the input shaft of the automatic transmission to be tested, use computer control commands to make the main pressure of the transmission reach the maximum value, and detect the actual clutch pressure value when current is applied to the clutch. When the minimum value of the clutch input current range is applied, the corresponding actual clutch pressure value is less than or equal to the set maximum value pressure at low pressure, and when the maximum value of the clutch input current range is applied, the corresponding actual clutch pressure value is greater than or equal to the set minimum value pressure at high pressure, then the clutch leakage detection passes; otherwise, the clutch leakage detection fails.

4. The method for detecting the off-line operation of a wet dual-clutch automatic transmission according to claim 1, characterized in that, The steps for hydraulic leak detection step two are as follows: When the transmission oil temperature is Y2, the main pressure of the transmission is brought to its maximum value through computer control commands. The maximum value of the clutch input current range is applied to the clutch. The input shaft of the automatic transmission to be tested is given several different speeds. The actual clutch pressure value at each input shaft speed is detected. When the actual clutch pressure value detected at the corresponding input shaft speed is greater than or equal to the set minimum pressure value at the corresponding input shaft speed, the hydraulic leak detection step two passes; otherwise, the hydraulic leak detection step two fails.

5. The method for detecting the off-line operation of a wet dual-clutch automatic transmission according to claim 1, characterized in that, The steps for clutch pressure current detection are as follows: Apply a rotational speed of N6 rpm to the input shaft of the automatic transmission under test. Using computer control commands, bring the transmission's main pressure to its maximum value. Apply control currents of different values ​​within the clutch solenoid valve's input current range to the clutch solenoid valve. Detect the actual clutch pressure value after each control current is applied. The clutch pressure current detection passes when the following conditions are met simultaneously: 1) The actual clutch pressure value at each control current, within the maximum and minimum pressure range set for the corresponding current value; 2) The maximum fluctuation of the actual clutch pressure value at each control current is less than or equal to the maximum fluctuation pressure value set at the corresponding current value. 3) When the control current is increasing, the corresponding actual clutch pressure value is also increasing, and the increment of the actual clutch pressure value is greater than or equal to the set minimum increment pressure value. If the above three conditions cannot be met simultaneously, the clutch pressure current detection will fail.

6. The method for detecting the off-line operation of a wet dual-clutch automatic transmission according to claim 1, characterized in that, The steps for half-engagement point detection are as follows: The input shaft of the automatic transmission to be tested is given a speed of N7 rpm. The main pressure of the transmission is brought to the maximum value through computer control commands. The clutch half-engagement point is self-learned by controlling the clutch solenoid valve to obtain the clutch half-engagement point position. When the clutch half-engagement point pressure is within the set maximum and minimum value range, the half-engagement point detection is passed; otherwise, the half-engagement point detection fails.

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