Automatic transmission input shaft rationality fault diagnosis system and diagnosis method thereof

Abstract

The invention discloses an automatic transmission input shaft rationality fault diagnosis system and a diagnosis method thereof, and belongs to the technical field of transmissions. Comprising a signal input module, a fault diagnosis module and a fault post-processing module. The P / N gear rationality fault diagnosis method comprises the following steps: confirming an effective state signal and an operation state signal; confirming that a transmission transmission chain is in a disconnected state; if the rotating speed of the input shaft falls to 0 or is smaller than or equal to the calibration value and lasts for preset time, the input shaft rotating speed rationality fault is diagnosed. The D / R gear rationality fault diagnosis method comprises the following steps: confirming an effective state signal and an operation state signal; when the transmission transmission chain is in a closed state, the input shaft rotation speed and the output shaft rotation speed are in a speed ratio relationship; and if the output shaft rotating speed is greater than the calibration value and the input shaft rotating speed falls to 0 or is less than or equal to the calibration value and lasts for a preset time, diagnosing that the input shaft rotating speed is reasonable. The method can accurately recognize the rationality fault of the rotating speed of the input shaft, and improves the accuracy and reliability of fault diagnosis.

Description

Technical Field

[0001] The invention relates to an automatic transmission input shaft rationality fault diagnosis system and a diagnosis method thereof, belonging to the technical field of transmissions. Background Art

[0002] During the normal operation of an automatic transmission, the input shaft speed, as a key parameter reflecting the power transmission status, should be maintained within a reasonable operating range under different gears. Accurate monitoring of this parameter is crucial for assessing the health of the transmission, preventing potential failures, and improving the driving experience. However, the existing technical system has obvious deficiencies in monitoring and diagnosing the rationality of the input shaft speed. Although the speed sensor can collect input shaft speed data in real time, if the speed value fluctuates unreasonably or is abnormal in the absence of electrical faults, traditional methods often find it difficult to effectively identify and locate the root cause of the problem.

[0003] When the input shaft speed data is abnormal, possible reasons include but are not limited to sensor signal interference, mechanical failure inside the transmission, failure of the hydraulic control system, and software algorithm errors. Due to the lack of direct diagnostic means for input shaft speed rationality failures, maintenance personnel can often only rely on experience or make extensive component replacement attempts, which not only increases maintenance costs and time, but may also complicate the problem due to misdiagnosis. Summary of the invention

[0004] In order to solve the problems existing in the background technology, the present invention provides an automatic transmission input shaft rationality fault diagnosis system and a diagnosis method thereof.

[0005] To achieve the above object, the present invention adopts the following technical scheme: an automatic transmission input shaft rationality fault diagnosis system, comprising

[0006] Signal input module, used to aggregate multiple input signals;

[0007] A fault diagnosis module is used to perform reasonable fault diagnosis on the input shaft;

[0008] The fault post-processing module is used for activating a fault indicator lamp to indicate a fault state after diagnosing an input shaft rationality fault; and then causing the transmission to enter a limp home mode.

[0009] The input signals include an input shaft speed signal, an input shaft speed state signal, an output shaft speed signal, an output shaft speed state signal, a handle signal, a handle state signal, an engine speed signal, an engine speed state signal, and an engine state signal.

[0010] The rationality fault includes a P / N gear rationality fault and a D / R gear rationality fault.

[0011] A method for diagnosing a P / N gear rationality fault of an automatic transmission input shaft rationality fault diagnosis system of the present invention comprises the following steps:

[0012] S1: Confirm that the input shaft speed status signal, the handle status signal, and the engine speed status signal are all valid status signals, and the engine status signal is a running status signal;

[0013] S2: confirm that the transmission chain is disconnected;

[0014] S3: If the input shaft speed drops to 0 or is less than or equal to the calibration value C1 and lasts for the preset time t1, it is diagnosed as an input shaft speed rationality fault.

[0015] A method for diagnosing a D / R gear rationality fault of an automatic transmission input shaft rationality fault diagnosis system of the present invention comprises the following steps:

[0016] S1: Confirm that the input shaft speed status signal, the handle status signal, and the output shaft speed status signal are all valid status signals, and the engine status signal is a running status signal;

[0017] S2: When the vehicle is running, the transmission chain is in a closed state, and the input shaft speed and the output shaft speed are in a speed ratio relationship;

[0018] S3: If the output shaft speed is greater than the calibration value C2, and the input shaft speed drops to 0 or is less than or equal to the calibration value C1 and lasts for the preset time t1, it is diagnosed as an input shaft speed rationality fault.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention can accurately identify the rationality fault of the input shaft speed by integrating multiple input signals, improve the accuracy and reliability of fault diagnosis, and help to timely discover and solve potential problems.

[0021] 2. The present invention can quickly locate the source of the fault, reducing the situation where maintenance personnel rely on experience or blindly replace parts, reducing maintenance costs, shortening maintenance time, and improving maintenance efficiency.

[0022] 3. When the input shaft rationality fault is diagnosed, the system will automatically activate the fault indicator light and put the transmission into limp mode, thus preventing the potential danger to the vehicle and driver caused by the expansion of the fault and ensuring the safety of the driving process. DETAILED DESCRIPTION

[0023] The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] An automatic transmission input shaft rationality fault diagnosis system, comprising:

[0025] Signal input module, used to aggregate multiple input signals;

[0026] A fault diagnosis module is used to perform reasonable fault diagnosis on the input shaft;

[0027] The fault post-processing module is used to activate the fault indicator light to indicate the fault status after diagnosing the rationality fault of the input shaft; and then put the gearbox into limp mode, which is specifically manifested as follows: when the P / N gear is shifted to the D / R gear, the solenoid valve is controlled according to a fixed action to form the D / R gear; when running in the D gear, the gearbox is fixed in a certain gear position and no up / down gear control is performed.

[0028] The input signals include an input shaft speed signal, an input shaft speed state signal, an output shaft speed signal, an output shaft speed state signal, a handle signal, a handle state signal, an engine speed signal, an engine speed state signal, and an engine state signal.

[0029] The rationality fault includes a P / N gear rationality fault and a D / R gear rationality fault. The P / N gear includes the P / N gear when the vehicle is stationary and also includes the N gear during driving.

[0030] A method for diagnosing a P / N gear rationality fault of an automatic transmission input shaft rationality fault diagnosis system of the present invention comprises the following steps:

[0031] S1: Confirm that the input shaft speed status signal, the handle status signal, and the engine speed status signal are all valid status signals, and the engine status signal is a running status signal;

[0032] A valid status signal is defined as the corresponding speed sensor having no electrical faults and not issuing an invalid status signal.

[0033] S2: Confirm that the transmission chain is disconnected; the transmission chain is the gear position that the transmission can transmit power, and reduce the power output. The transmission chain disconnection state means that there is no effective gear position, and power cannot be output. The turbine rotates with the engine speed under the action of the torque converter, and the turbine speed value is less than the engine speed value.

[0034] S3: If the input shaft speed drops to 0 or is less than or equal to the calibration value C1 and lasts for the preset time t1, it is diagnosed as an input shaft speed rationality fault.

[0035] The calibration value C1 is preferably calibrated to 20 rpm, and the time t1 is preferably 2 s.

[0036] A method for diagnosing a D / R gear rationality fault of an automatic transmission input shaft rationality fault diagnosis system of the present invention comprises the following steps:

[0037] S1: Confirm that the input shaft speed status signal, the handle status signal, and the output shaft speed status signal are all valid status signals, and the engine status signal is a running status signal;

[0038] A valid status signal is defined as the corresponding speed sensor having no electrical faults and not issuing an invalid status signal.

[0039] S2: When the vehicle is running, the transmission chain is in a closed state, and the input shaft speed and the output shaft speed are in a speed ratio relationship; the transmission chain is the gear position of the transmission to determine whether the transmission can transmit power, and the power output is reduced. The closed state of the transmission chain means that an effective gear position is formed and power can be output.

[0040] S3: If the output shaft speed is greater than the calibration value C2, and the input shaft speed drops to 0 or is less than or equal to the calibration value C1 and lasts for the preset time t1, it is diagnosed as an input shaft speed rationality fault.

[0041] The calibration value C2 is preferably calibrated to 200 rpm.

[0042] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalents of the claims be included in the present invention.

[0043] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An automatic transmission input shaft rationality fault diagnosis system, characterized in that: include A signal input module is used to aggregate multiple input signals; A fault diagnosis module is used to perform reasonable fault diagnosis on the input shaft; The fault post-processing module is used for activating a fault indicator lamp to indicate a fault state after diagnosing an input shaft rationality fault; and then causing the transmission to enter a limp home mode.

2. The automatic transmission input shaft rationality fault diagnosis system according to claim 1, characterized in that: The input signals include an input shaft speed signal, an input shaft speed state signal, an output shaft speed signal, an output shaft speed state signal, a handle signal, a handle state signal, an engine speed signal, an engine speed state signal, and an engine state signal.

3. The automatic transmission input shaft rationality fault diagnosis system according to claim 1, characterized in that: The rationality fault includes a P / N gear rationality fault and a D / R gear rationality fault.

4. A method for diagnosing a P / N gear rationality fault of an automatic transmission input shaft rationality fault diagnosis system according to claim 3, characterized in that: The method comprises the following steps: S1: Confirm that the input shaft speed status signal, the handle status signal, and the engine speed status signal are all valid status signals, and the engine status signal is a running status signal; S2: confirm that the transmission chain is disconnected; S3: If the input shaft speed drops to 0 or is less than or equal to the calibration value C1 and lasts for the preset time t1, it is diagnosed as an input shaft speed rationality fault.

5. A method for diagnosing a D / R gear rationality fault of an automatic transmission input shaft rationality fault diagnosis system according to claim 3, characterized in that: The method comprises the following steps: S1: Confirm that the input shaft speed status signal, the handle status signal, and the output shaft speed status signal are all valid status signals, and the engine status signal is a running status signal; S2: When the vehicle is running, the transmission chain is in a closed state, and the input shaft speed and the output shaft speed are in a speed ratio relationship; S3: If the output shaft speed is greater than the calibration value C2, and the input shaft speed drops to 0 or is less than or equal to the calibration value C1 and lasts for the preset time t1, it is diagnosed as an input shaft speed rationality fault.