Fault diagnosis method and device for braking capacity of AMT intermediate shaft brake and vehicle

Abstract

The invention discloses a fault diagnosis method and device for the braking capacity of an AMT intermediate shaft brake and a vehicle. The fault diagnosis method comprises the steps of obtaining a vehicle power-on signal when a vehicle is in a static state; setting all data in the valve opening time MAP table corresponding to the temperature-intermediate shaft rotating speed drop as 0; wherein the MAP table represents the value of the valve opening time determined by the temperature and the rotating speed drop of the intermediate shaft; a gear switching command is sent to control the transmission to execute switching operation from the N gear to the D gear; in the switching operation process, the current gear of the transmission and the rotating speed of an intermediate shaft are monitored; the fault grade of the clutch and the guide bearing is judged by monitoring whether the transmission is successfully engaged with the gear or not and according to the first average speed reduction rate, the second average speed reduction rate, the first set speed reduction rate and the second set speed reduction rate of the intermediate shaft. The fault levels of the clutch and the guide bearing can be distinguished.

Description

Technical Field

[0001] This invention relates to the field of fault diagnosis technology, and in particular to a fault diagnosis method, device and vehicle for the braking capability of an AMT intermediate shaft brake. Background Technology

[0002] In the automotive industry, automated manual transmissions (AMTs) are widely used due to their advantages such as simple structure, low cost, and high transmission efficiency. However, the intermediate shaft brake, as a key component for gear shifting, is susceptible to high temperatures, wear, and installation process issues, often resulting in slow shifting or inability to shift gears, seriously threatening driving safety and experience.

[0003] Current technologies for diagnosing faults in components such as intermediate shaft brakes primarily rely on reactive troubleshooting after problems occur, which has significant limitations. The diagnostic process depends on maintenance experience, making it difficult to pinpoint the root cause of the fault in real time and to differentiate the fault severity. Summary of the Invention

[0004] This invention provides a method, apparatus, and vehicle for diagnosing the braking capability of an AMT intermediate shaft brake, in order to solve the problem of being unable to distinguish the level of fault.

[0005] In a first aspect, embodiments of the present invention provide a fault diagnosis method for the braking capability of an AMT intermediate shaft brake, the fault diagnosis method comprising:

[0006] When the vehicle is stationary, after receiving the power-on signal of the vehicle, all data in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop are set to 0; wherein, the MAP table represents the value of valve opening time determined by temperature and intermediate shaft speed drop;

[0007] Send a gear shift command to control the transmission to perform a shift operation from N to D gear;

[0008] During the switching operation, the current gear of the transmission and the rotational speed of the intermediate shaft are monitored;

[0009] The fault level of the clutch and guide bearing is determined by monitoring whether the transmission can be successfully engaged and by the first average deceleration rate, the second average deceleration rate, the first set deceleration rate and the second set deceleration rate of the intermediate shaft.

[0010] Optionally, the step of monitoring whether the transmission successfully engages a gear and determining the fault level of the clutch and guide bearing based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft includes:

[0011] If the transmission cannot be engaged in D gear and the intermediate shaft speed remains unchanged, it is determined that the clutch and the guide bearing cannot disengage, the clutch is faulty, and the fault level is high.

[0012] Optionally, the step of monitoring whether the transmission successfully engages a gear and determining the fault level of the clutch and guide bearing based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft includes:

[0013] If the transmission is successfully engaged in D gear, then the first average deceleration rate of the intermediate shaft is calculated.

[0014] If the first average deceleration rate is less than the first set deceleration rate, then it is determined that the clutch and the guide bearing are stuck and the clutch is faulty, and the fault level is medium.

[0015] Optionally, calculating the first average deceleration rate of the intermediate shaft includes:

[0016] After the gear shifting command is issued, the first rotational speed of the intermediate shaft is collected after a first delay time, and the first current time is obtained.

[0017] When the intermediate shaft speed reaches a set percentage of the engine idle speed, a second speed and a second current time are obtained;

[0018] Based on the first rotational speed, the first current time, the second rotational speed, and the second current time, calculate the first deceleration rate of the intermediate shaft in the current state;

[0019] The above process is repeated three times to obtain the first average deceleration rate of the intermediate shaft.

[0020] Optionally, after calculating the speed reduction rate of the intermediate shaft if the transmission is successfully engaged in D gear, the method further includes:

[0021] If the first average deceleration rate is greater than or equal to the first set deceleration rate, then the valve opening time in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop is set as the first valve opening time.

[0022] Send a gear shift command to control the transmission to perform a shift operation from N gear to D gear, and monitor the current gear of the transmission and the speed of the intermediate shaft during the shift operation;

[0023] Calculate the second average deceleration rate of the intermediate shaft;

[0024] If the second average deceleration rate of the intermediate shaft is less than the second set deceleration rate, then the braking force of the intermediate shaft is determined to be weakened, and the fault level is primary.

[0025] Optionally, calculating the second average deceleration rate of the intermediate shaft includes:

[0026] After the gear shift command is issued, the third rotational speed of the intermediate shaft is collected after a second delay time, and the third current time is obtained.

[0027] When the intermediate shaft speed reaches a set percentage of the engine idle speed, the fourth speed and the fourth current time are obtained;

[0028] Based on the third rotational speed, the third current time, the fourth rotational speed, and the fourth current time, calculate the second deceleration rate of the intermediate shaft in the current state;

[0029] The above process is repeated three times to obtain the second average deceleration rate of the intermediate shaft.

[0030] Optionally, after calculating the second average deceleration rate of the intermediate shaft, the method further includes:

[0031] If the second average deceleration rate of the intermediate shaft is greater than or equal to the second set deceleration rate, then the intermediate shaft brake is determined to be working normally.

[0032] Optionally, after monitoring whether the transmission is successfully engaged and determining the fault level of the clutch and guide bearing based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft, the initial default value of the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop is restored.

[0033] Secondly, embodiments of the present invention provide a fault diagnosis device for the braking capability of an AMT intermediate shaft brake, comprising at least:

[0034] The initialization operation module is used to set all data in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop to 0 after obtaining the power-on signal of the vehicle when the vehicle is stationary.

[0035] The gear shifting module is used to send gear shifting commands to control the transmission to perform the shifting operation from N gear to D gear;

[0036] The status monitoring module is used to monitor the current gear of the transmission and the rotational speed of the intermediate shaft during the switching operation.

[0037] The fault diagnosis module is used to determine the fault level of the clutch and guide bearing by monitoring whether the transmission is successfully engaged and based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft.

[0038] Thirdly, embodiments of the present invention also provide a vehicle including a TCU controller, the TCU controller performing a fault diagnosis method for the braking capability of an AMT intermediate shaft brake as provided in any embodiment of the present invention.

[0039] The fault diagnosis method for the braking capability of the AMT intermediate shaft brake provided in this invention solves the problem of misjudgment caused by operating condition interference by limiting the static scenario of the vehicle. By setting the temperature-intermediate shaft speed drop corresponding to the valve opening time MAP table data to 0, the influence of the intermediate shaft brake is shielded, allowing the diagnosis to focus on the clutch and guide bearing, thus solving the problem of inaccurate fault diagnosis location. Furthermore, by sending a gear shift command to control the transmission to perform a shift operation from N to D, and combining the transmission's successful gear engagement status with the comparison results of the first average deceleration rate and the first set deceleration rate of the intermediate shaft, and the comparison results of the second average deceleration rate and the first set deceleration rate, the fault level of the clutch and guide bearing is comprehensively determined. This solves the problem of relying on experience judgment and being unable to distinguish fault levels in fault diagnosis. This fault diagnosis method has the beneficial effects of clear fault location, easy and rapid fault location investigation, accurate fault level classification, and adaptability to brake performance changes under different operating conditions.

[0040] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a flowchart of a fault diagnosis method for the braking capability of an AMT intermediate shaft brake provided in an embodiment of the present invention;

[0043] Figure 2 This is a flowchart of another method for diagnosing the braking capability of an AMT intermediate shaft brake provided in an embodiment of the present invention;

[0044] Figure 3 This is a schematic diagram of the structure of a fault diagnosis device for the braking capability of an AMT intermediate shaft brake provided in an embodiment of the present invention. Detailed Implementation

[0045] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0046] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0047] Figure 1 This is a flowchart illustrating a fault diagnosis method for the braking capability of an AMT intermediate shaft brake according to an embodiment of the present invention. This embodiment is applicable to fault diagnosis of the braking capability of an AMT intermediate shaft brake. The method can be executed by a fault diagnosis device, which can be implemented in hardware and / or software and can be configured in the TCU controller. Figure 1 As shown, the method includes the following steps:

[0048] S110. When the vehicle is stationary, after receiving the vehicle's power-on signal, set all data in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop to 0.

[0049] The MAP table represents the valve opening time value determined by temperature and intermediate shaft speed drop.

[0050] S120: Send a gear shift command to control the transmission to perform a shift operation from N to D gear.

[0051] S130. During the switching operation, monitor the current gear of the transmission and the speed of the intermediate shaft.

[0052] S140. By monitoring whether the transmission is successfully engaged and based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft, the fault level of the clutch and the guide bearing is determined.

[0053] By limiting the diagnostics to a stationary state, interference from operating conditions during driving can be eliminated, ensuring that subsequent data such as gear shifting status and intermediate shaft speed changes only reflect the working status of internal transmission components, thus avoiding deviations in diagnostic results caused by external factors. Setting all data in the temperature-intermediate shaft speed drop corresponding to valve opening time MAP table to 0 cuts off the control signal of the intermediate shaft brake, preventing it from participating in the gear shifting process. This allows the fault diagnosis to focus on the clutch and guide bearing components, preventing the braking action of the brake from masking or interfering with the fault characteristics of these components, and achieving precise fault location.

[0054] The first average deceleration rate and the second average deceleration rate are the average speed at which the intermediate shaft speed decreases during the gear shift test; the first set deceleration rate and the second set deceleration rate are the minimum deceleration standards that the intermediate shaft should reach under normal conditions, as preset.

[0055] The fault diagnosis method for the braking capability of the AMT intermediate shaft brake provided in this invention solves the problem of misjudgment caused by operating condition interference by limiting the static scenario of the vehicle. By setting the temperature-intermediate shaft speed drop corresponding to the valve opening time MAP table data to 0, the influence of the intermediate shaft brake is shielded, allowing the diagnosis to focus on the clutch and guide bearing, thus solving the problem of inaccurate fault diagnosis location. By sending a gear shift command to control the transmission to perform a shift operation from N to D, and combining the transmission's successful gear engagement status with the comparison results of the first average deceleration rate and the first set deceleration rate of the intermediate shaft, and the comparison results of the second average deceleration rate and the first set deceleration rate, the fault level of the clutch and guide bearing is comprehensively determined. This solves the problem of relying on experience judgment and being unable to distinguish fault levels in fault diagnosis. This fault diagnosis method has the beneficial effects of clear fault location, easy and rapid fault location investigation, accurate fault level classification, and adaptability to brake performance changes under different operating conditions.

[0056] Optionally, there are various ways to implement S140, which involves monitoring whether the transmission is successfully engaged and determining the fault level of the clutch and guide bearing based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft. These methods will be described in detail below, but are not intended to limit the present invention.

[0057] In one embodiment, optionally, S140 includes:

[0058] If the transmission cannot be engaged in D gear and the intermediate shaft speed remains unchanged, it is determined that the clutch and guide bearing cannot disengage, indicating a clutch malfunction, and the malfunction level is high.

[0059] The current gear position of the transmission indicates whether the shift was successful, while the speed of the intermediate shaft indicates whether the clutch disengagement was complete. The inability to engage D gear indicates that the shifting mechanism has not completed mechanical engagement, reflecting a hardware system fault in the transmission. A constant intermediate shaft speed indicates that the clutch and guide bearing cannot disengage, causing engine power to be continuously transmitted to the intermediate shaft, preventing its speed from decreasing and hindering gear engagement. This type of fault will cause the vehicle to lose its shifting ability, which is an emergency issue affecting driving safety; therefore, the fault level is classified as high.

[0060] In another embodiment, S140 may optionally include:

[0061] If the transmission is successfully engaged in D gear, the first average deceleration rate of the intermediate shaft is calculated.

[0062] If the first average deceleration rate is less than the first set deceleration rate, it is determined that the clutch and guide bearing are stuck and the clutch is faulty, with the fault level being medium.

[0063] The first average deceleration rate reflects the degree of disengagement between the clutch and the guide bearing. The more complete the disengagement, the more completely the engine power is cut off, and the faster the intermediate shaft speed decreases. The first set deceleration rate represents the basic deceleration capability when the clutch and guide bearing are not stuck. Clutch and guide bearing disengagement jamming will cause the engine power to not be completely cut off, continuing to drive the intermediate shaft rotation, thus resulting in a slow speed decrease. When the first average deceleration rate is less than the first set deceleration rate, it indicates that the intermediate shaft speed decreases slower than normal, the root cause of which is clutch and guide bearing disengagement jamming. Although this type of fault does not cause gear shifting failure, incomplete disengagement can lead to shifting jerks, accelerated wear, and other problems, classifying it as a moderate fault requiring timely repair, hence the fault level is determined to be medium.

[0064] Optionally, the first average deceleration rate of the intermediate shaft is calculated, including:

[0065] After the gear shift command is issued, the first rotational speed of the intermediate shaft is collected after the first delay time, and the first current time is obtained.

[0066] When the intermediate shaft speed reaches a set percentage of the engine idle speed, the second speed and the second current time are obtained.

[0067] Calculate the first deceleration rate of the intermediate shaft in the current state based on the first rotational speed, the first current time, the second rotational speed, and the second current time.

[0068] The above process is repeated three times to obtain the first average deceleration rate of the intermediate shaft.

[0069] The method of acquiring the first rotational speed of the intermediate shaft after a first delay avoids mechanical shock interference during the initial shift, such as the speed fluctuation at the moment the gears begin to mesh, ensuring that the data acquired is the initial data of the stable deceleration phase. Engine idling speed refers to the state in which the engine operates at its lowest stable speed under no external load. The set percentage of the intermediate shaft speed reaching the engine idling speed indicates that it is close to the stable state after the shift is completed. Choosing this node as the endpoint can objectively reflect the efficiency of the entire deceleration process. The first deceleration rate (denoted as K1) is calculated by the formula K1 = (R1 - R2) / (T2 - T1). In the formula, R1 is the first rotational speed, R2 is the second rotational speed, T1 is the first current time, and T2 is the second current time. For example, the first delay time is 200 milliseconds, and the set percentage is 20%. This embodiment of the invention uses the average of the three calculated deceleration rates as a comparison value with the corresponding set deceleration rate to improve the accuracy of intermediate shaft brake fault diagnosis.

[0070] In another embodiment, optionally, after calculating the intermediate shaft speed reduction rate if the transmission is successfully engaged in D gear, the method further includes:

[0071] If the first average deceleration rate is greater than or equal to the first set deceleration rate, then the valve opening time in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed reduction is set as the first valve opening time.

[0072] Send a gear shift command to control the transmission to perform a shift operation from N to D gear, and monitor the current gear of the transmission and the speed of the intermediate shaft during the shift operation.

[0073] Calculate the second average deceleration rate of the intermediate shaft.

[0074] If the second average deceleration rate of the intermediate shaft is less than the second set deceleration rate, the braking force of the intermediate shaft is determined to be weakened, and the fault level is primary.

[0075] The first valve opening time is the standard valve opening duration retrieved from the MAP table based on the current temperature and speed of the intermediate shaft to ensure normal operation of the intermediate shaft brake. A longer first valve opening time results in stronger braking force from the intermediate shaft brake and faster deceleration of the intermediate shaft. Setting the valve opening time from the MAP table corresponding to temperature-intermediate shaft speed reduction as the first valve opening time means that the brake is no longer disabled, but rather engaged in the shifting process through the first valve opening time. Since the brake is activated, the deceleration of the intermediate shaft is achieved by the combined action of clutch disengagement and brake braking. The second average deceleration rate refers to the average speed at which the intermediate shaft speed decreases after the brake engages. The second set deceleration rate refers to the pre-calibrated minimum deceleration standard that should be achieved when the brake is working normally. When the second average deceleration rate is less than the second set deceleration rate, it indicates that the actual deceleration effect has not met the standard, and the root cause is the decline in braking force of the intermediate shaft. This type of fault leads to brake function degradation and is a minor problem requiring regular maintenance but not emergency repair; therefore, the fault level is classified as primary. This invention first eliminates clutch malfunctions by ensuring the first average deceleration rate meets the standard, then activates the brake to repeat the gear shifting test, and finally locks the brake's braking force fade by ensuring the second average deceleration rate does not meet the standard. This fault diagnosis can avoid confusing brake malfunctions with clutch malfunctions and pinpoint the faulty component.

[0076] Optionally, the second average deceleration rate of the intermediate shaft is calculated, including:

[0077] After the gear shift command is issued, the third rotational speed of the intermediate shaft is collected after a second delay time, and the third current time is obtained.

[0078] When the intermediate shaft speed reaches a set percentage of the engine idle speed, the fourth speed and the fourth current time are obtained.

[0079] Calculate the second deceleration rate of the intermediate shaft in the current state based on the third rotational speed, the third current time, the fourth rotational speed, and the fourth current time.

[0080] The above process is repeated three times to obtain the second average deceleration rate of the intermediate shaft.

[0081] The second deceleration rate (denoted as K2) is calculated using the formula K2 = (R3 - R4) / (T4 - T3). In this formula, R3 is the third rotational speed, R4 is the fourth rotational speed, T3 is the third current time, and T4 is the fourth current time.

[0082] Optionally, after calculating the second average deceleration rate of the intermediate shaft, the method further includes:

[0083] If the second average deceleration rate of the intermediate shaft is greater than or equal to the second set deceleration rate, the intermediate shaft brake is determined to be working normally.

[0084] Specifically, when the second average deceleration rate is greater than or equal to the second set deceleration rate, it indicates that the brake has output sufficient braking force according to the command of the first valve opening time, effectively assisting the intermediate shaft in rapid deceleration and meeting the braking force requirements during gear shifting. There is no problem of braking force fade, and it can be determined that the intermediate shaft brake is working normally. For example, the fault diagnosis results of the above embodiment are displayed and prompted through the vehicle's instrument panel.

[0085] Based on the above embodiments, optionally, after S140, the initial default value of the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop is restored.

[0086] Restoring the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop to its initial default value ensures that the next fault diagnosis always starts from the standard initial state. If the MAP table default value is not restored after the current diagnosis, the system will still call the first valve opening time previously set for fault location during the next diagnosis. This can lead to data deviations in the early stages of diagnosis. For example, if the MAP table parameters are not reset, the brake may actually operate at a non-default value, but the system may mistakenly identify this abnormal brake operation as a fault in the brake itself, ultimately compromising the accuracy of the fault diagnosis and causing misjudgment.

[0087] Figure 2 This is a flowchart of another method for diagnosing the braking capability of an AMT intermediate shaft brake provided in an embodiment of the present invention. (See also...) Figure 2 Based on the above embodiments, the fault diagnosis method may optionally include the following steps:

[0088] S210. Power on the vehicle and begin static testing.

[0089] S220. Set all data in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop to 0;

[0090] The S230 and TCU controllers send gear shifting commands to control the transmission to shift from N to D gear.

[0091] S240: Determine if the transmission is in D gear; if yes, proceed to S250; otherwise, proceed to S260.

[0092] S250, intermediate shaft speed remains constant, clutch and guide bearing cannot disengage, advanced output fault;

[0093] S260, Calculate the first average deceleration rate K1 of the intermediate shaft;

[0094] Specifically, S260 includes:

[0095] S261. After the gear shift command is issued, the first rotational speed R1 of the intermediate shaft is collected after the first delay time and the first current time T1 is obtained; when the rotational speed of the intermediate shaft reaches the set percentage of the engine idle speed, the second rotational speed R2 and the second current time T2 are obtained.

[0096] S262, K1 = (R1-R2) / (T2-T1), repeat three times and take the average value;

[0097] S270. Determine whether the first average deceleration rate is less than the first set deceleration rate; if yes, proceed to S280; otherwise, proceed to S290.

[0098] S280, clutch and guide bearing separation stuck, intermediate-level output fault;

[0099] S290, Set the valve opening time of the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop to the first valve opening time;

[0100] The S310 and TCU controllers send gear shifting commands to control the transmission to perform the shifting operation from N to D gear, and monitor the current gear of the transmission and the speed of the intermediate shaft.

[0101] S320, Calculate the second average deceleration rate K2 of the intermediate shaft (same as K1 algorithm);

[0102] S330: Determine whether the second average deceleration rate is less than the second set deceleration rate; if yes, execute S350; otherwise, execute S340.

[0103] S340, the intermediate shaft brake is working normally;

[0104] S350, intermediate shaft braking force decline, fault level is primary;

[0105] S360, the vehicle's instrument panel displays and indicates faults;

[0106] S370, Recovery Temperature - Intermediate Shaft Speed ​​Drop Corresponding Valve Opening Time MAP Table Initial Default Value

[0107] In summary, this embodiment of the invention first sets the MAP data to 0 to shield the brake, and then determines the state of the clutch and guide bearing through the first average deceleration rate; next, it sets a first valve opening time to activate the brake, and tests the brake performance separately through the second average deceleration rate. This component-based testing method can clearly distinguish whether the fault originates from the clutch or the brake, achieving precise fault source location and facilitating rapid troubleshooting. Furthermore, this embodiment of the invention classifies faults into three levels—high, medium, and low—based on a quantitative comparison of deceleration rates, while clearly defining the criteria for determining normal conditions. This fault classification allows maintenance personnel to assess the severity of the fault, providing direction for repairs and improving efficiency. In addition, this embodiment of the invention dynamically adjusts the parameters of the MAP table related to temperature-speed drop, and the testing process is based on actual gear shifting actions, more closely resembling real-world vehicle usage scenarios. It can adapt to changes in brake performance under different operating conditions, achieving effective diagnosis and enhancing practicality.

[0108] Figure 3 This is a schematic diagram of the structure of a fault diagnosis device for the braking capability of an AMT intermediate shaft brake provided in an embodiment of the present invention. Figure 3 As shown, the device includes at least:

[0109] The initialization operation module 410 is used to set all data in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop to 0 after obtaining the power-on signal of the vehicle when the vehicle is stationary.

[0110] The gear shifting module 420 is used to send gear shifting commands to control the transmission to perform the shifting operation from N gear to D gear.

[0111] The status monitoring module 430 is used to monitor the current gear position of the transmission and the rotational speed of the intermediate shaft during the switching operation.

[0112] The fault diagnosis module 440 is used to determine the fault level of the clutch and guide bearing by monitoring whether the transmission is successfully engaged and based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft.

[0113] Optionally, the fault diagnosis module 440 is specifically used for:

[0114] If the transmission cannot be engaged in D gear and the intermediate shaft speed remains unchanged, it is determined that the clutch and guide bearing cannot disengage, indicating a clutch malfunction, and the malfunction level is high.

[0115] If the first average deceleration rate is less than the first set deceleration rate, it is determined that the clutch and guide bearing are stuck and the clutch is faulty, with the fault level being medium.

[0116] If the second average deceleration rate of the intermediate shaft is less than the second set deceleration rate, the braking force of the intermediate shaft is determined to be weakened, and the fault level is primary.

[0117] If the second average deceleration rate of the intermediate shaft is greater than or equal to the second set deceleration rate, the intermediate shaft brake is determined to be working normally.

[0118] The fault diagnosis device for the braking capability of an AMT intermediate shaft brake provided in this embodiment of the invention can execute the fault diagnosis method for the braking capability of an AMT intermediate shaft brake provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0119] Optionally, embodiments of the present invention also provide a vehicle including a TCU controller, which executes a fault diagnosis method for the braking capability of the AMT intermediate shaft brake as provided in any embodiment of the present invention, and has corresponding beneficial effects.

[0120] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0121] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for diagnosing the braking capability of an AMT intermediate shaft brake, characterized in that, The fault diagnosis method includes: When the vehicle is stationary, after receiving the power-on signal of the vehicle, all data in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop are set to 0; wherein, the MAP table represents the value of valve opening time determined by temperature and intermediate shaft speed drop; Send a gear shift command to control the transmission to perform a shift operation from N to D gear; During the switching operation, the current gear of the transmission and the rotational speed of the intermediate shaft are monitored; The fault level of the clutch and guide bearing is determined by monitoring whether the transmission can be successfully engaged and by the first average deceleration rate, the second average deceleration rate, the first set deceleration rate and the second set deceleration rate of the intermediate shaft.

2. The method for fault diagnosis of the braking capability of an AMT intermediate shaft brake according to claim 1, characterized in that, The method of monitoring whether the transmission successfully engages a gear and determining the fault level of the clutch and guide bearing based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft includes: If the transmission cannot be engaged in D gear and the intermediate shaft speed remains unchanged, it is determined that the clutch and the guide bearing cannot disengage, the clutch is faulty, and the fault level is high.

3. The fault diagnosis method for the braking capability of an AMT intermediate shaft brake according to claim 1, characterized in that, The method of monitoring whether the transmission successfully engages a gear and determining the fault level of the clutch and guide bearing based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft includes: If the transmission is successfully engaged in D gear, then the first average deceleration rate of the intermediate shaft is calculated. If the first average deceleration rate is less than the first set deceleration rate, then it is determined that the clutch and the guide bearing are stuck and the clutch is faulty, and the fault level is medium.

4. The method for fault diagnosis of braking capability of an AMT intermediate shaft brake according to claim 3, characterized in that, The calculation of the first average deceleration rate of the intermediate shaft includes: After the gear shifting command is issued, the first rotational speed of the intermediate shaft is collected after a first delay time, and the first current time is obtained. When the intermediate shaft speed reaches a set percentage of the engine idle speed, a second speed and a second current time are obtained; Based on the first rotational speed, the first current time, the second rotational speed, and the second current time, calculate the first deceleration rate of the intermediate shaft in the current state; The above process is repeated three times to obtain the first average deceleration rate of the intermediate shaft.

5. The method for fault diagnosis of braking capability of an AMT intermediate shaft brake according to claim 3, characterized in that, After calculating the speed reduction rate of the intermediate shaft if the transmission is successfully engaged in D gear, the method further includes: If the first average deceleration rate is greater than or equal to the first set deceleration rate, then the valve opening time in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop is set as the first valve opening time. Send a gear shift command to control the transmission to perform a shift operation from N gear to D gear, and monitor the current gear of the transmission and the speed of the intermediate shaft during the shift operation; Calculate the second average deceleration rate of the intermediate shaft; If the second average deceleration rate of the intermediate shaft is less than the second set deceleration rate, then the braking force of the intermediate shaft is determined to be weakened, and the fault level is primary.

6. The fault diagnosis method for the braking capability of an AMT intermediate shaft brake according to claim 5, characterized in that, The calculation of the second average deceleration rate of the intermediate shaft includes: After the gear shift command is issued, the third rotational speed of the intermediate shaft is collected after a second delay time, and the third current time is obtained. When the intermediate shaft speed reaches a set percentage of the engine idle speed, the fourth speed and the fourth current time are obtained; Based on the third rotational speed, the third current time, the fourth rotational speed, and the fourth current time, calculate the second deceleration rate of the intermediate shaft in the current state; The above process is repeated three times to obtain the second average deceleration rate of the intermediate shaft.

7. The method for fault diagnosis of braking capability of an AMT intermediate shaft brake according to claim 5, characterized in that, After calculating the second average deceleration rate of the intermediate shaft, the method further includes: If the second average deceleration rate of the intermediate shaft is greater than or equal to the second set deceleration rate, then the intermediate shaft brake is determined to be working normally.

8. The method for fault diagnosis of braking capability of an AMT intermediate shaft brake according to claim 1, characterized in that, After monitoring whether the transmission is successfully engaged and determining the fault level of the clutch and guide bearing based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft, the initial default value of the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop is restored.

9. A fault diagnosis device for the braking capability of an AMT intermediate shaft brake, characterized in that, At least including: The initialization operation module is used to set all data in the valve opening time MAP table corresponding to the temperature-intermediate shaft speed drop to 0 after obtaining the power-on signal of the vehicle when the vehicle is stationary. The gear shifting module is used to send gear shifting commands to control the transmission to perform the shifting operation from N gear to D gear; The status monitoring module is used to monitor the current gear of the transmission and the rotational speed of the intermediate shaft during the switching operation. The fault diagnosis module is used to determine the fault level of the clutch and guide bearing by monitoring whether the transmission is successfully engaged and based on the first average deceleration rate, the second average deceleration rate, the first set deceleration rate, and the second set deceleration rate of the intermediate shaft.

10. A vehicle, characterized in that, Includes a TCU controller, which performs a fault diagnosis method for the braking capability of the AMT intermediate shaft brake as described in any one of claims 1-8.

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