Method for monitoring running state of planetary mechanism of automatic transmission

Abstract

The invention discloses an automatic transmission planetary mechanism running state monitoring method and belongs to the technical field of transmissions. Disassembling the to-be-tested transmission and then taking out a gear ring of the planetary mechanism; four uniformly distributed points are punched on the end face of the gear ring; a magnet sensor is mounted at each point position; performing trepanning treatment on the transmission shell according to the digital-analog position; the gear ring and other parts are installed back to the transmission again; after it is confirmed that the magnet inductor can be observed in the open holes of the transmission shell, a magnetic rotating speed sensor is installed in each open hole, and gaps between the magnetic rotating speed sensors and the transmission shell are sealed and plugged; testing a plurality of working conditions of the to-be-tested transmission, and recording a test result; and judging the working state of the planetary mechanism through a test result. The rotating speed of the gear ring is monitored in real time, and the working state of each part of the planetary mechanism is calculated and confirmed through the geometrical relationship of the planetary mechanism, so that the running condition of each part is comprehensively evaluated, and potential faults can be found and prevented in time.

Description

Technical Field

[0001] The invention relates to a method for monitoring the operating state of a planetary mechanism of an automatic transmission, and belongs to the technical field of transmissions. Background Art

[0002] Ensuring the reliability and durability of the automatic transmission in different usage scenarios requires not only that the automatic transmission can work stably under normal driving conditions, but also that it has the ability to cope with abnormal driving scenarios within a certain range to reduce the impact of potential failures on vehicle driving safety.

[0003] Currently, most automatic transmissions on the market use the Ravenna sun gear planetary mechanism as their core shifting mechanism. This mechanism achieves smooth shifting of gears by precisely controlling the movement of key components such as the sun gear and planetary carrier in different states. Although this design performs well in improving shifting efficiency and driving experience, it still faces some challenges in practical applications.

[0004] Specifically, under relatively loose constraints, the Ravenna sun gear planetary mechanism may experience spontaneous disordered operation due to factors such as assembly accuracy and dimensional tolerance. In most cases, this disordered operation has limited impact on the overall performance of the transmission system, but under extreme operating conditions, it may cause serious transmission failures and even lead to catastrophic consequences such as transmission fragmentation. Furthermore, due to the high degree of integration of modern automatic transmissions and the fact that the planetary mechanism is usually located at the core of the transmission, it becomes extremely difficult to comprehensively monitor the operating status of each component under different operating conditions through conventional testing methods. This technical bottleneck not only limits manufacturers' in-depth research on transmission performance optimization and fault prevention, but also increases the uncertainty risks faced by consumers during use. Summary of the invention

[0005] In order to solve the problems existing in the background technology, the present invention provides a method for monitoring the operating status of a planetary mechanism of an automatic transmission.

[0006] To achieve the above object, the present invention adopts the following technical solution: a method for monitoring the operating state of a planetary mechanism of an automatic transmission, the method comprising the following steps:

[0007] S1: disassemble the transmission to be tested and take out the ring gear of the planetary mechanism;

[0008] S2: Make four evenly spaced points on the end face of the gear ring;

[0009] S3: A magnetic sensor is installed at each point;

[0010] S4: Perform hole opening processing on the transmission housing according to the digital model position;

[0011] S5: Reinstall the ring gear and other parts obtained in S3 back into the transmission;

[0012] S6: After confirming that the opening of the transmission housing can observe the magnet sensor, a magnetic speed sensor is installed in each opening, and the gap between the magnetic speed sensor and the transmission housing is sealed;

[0013] S7: Perform various working condition tests on the transmission to be tested and record the test results;

[0014] S8: Determine the working status of the planetary mechanism based on the test results.

[0015] S801: Obtain the rotation speed Nc of the planet carrier;

[0016] S802: Obtain the rotation speed Nr of the ring gear;

[0017] S803: Calculate the speed ratio i of the planetary mechanism according to the known parameters of the planetary mechanism:

[0018] i=(Zr+Zs) / Zs(1)

[0019] In formula (1):

[0020] Zr is the number of teeth on the ring gear;

[0021] Zs is the number of sun gear teeth;

[0022] S804: Calculate the rotation speed Ns of the sun gear:

[0023] Ns=(Nc+i·Nr) / (1+i)(2).

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention monitors the rotation speed of the ring gear in real time under laboratory or whole vehicle conditions, calculates and confirms the working status of each component of the planetary mechanism through the geometric relationship of the planetary mechanism, thereby comprehensively evaluating the operation of each component, being able to timely discover and prevent potential failures, improving the stability and reliability of the overall operation of the transmission, extending its service life, and filling the gap in understanding the working status of the planetary mechanism under all working conditions in the whole machine state. DETAILED DESCRIPTION

[0026] 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.

[0027] A method for monitoring the operating state of a planetary mechanism of an automatic transmission, the method comprising the following steps:

[0028] S1: disassemble the transmission to be tested and take out the ring gear of the planetary mechanism;

[0029] S2: Make four evenly spaced points on the end face of the gear ring at 90° of the pitch circle;

[0030] S3: A magnetic sensor is installed at each point;

[0031] S4: Perform hole opening processing on the transmission housing according to the digital model position;

[0032] S5: Reinstall the ring gear and other parts obtained in S3 back into the transmission;

[0033] S6: After confirming that the opening of the transmission housing can observe the magnet sensor, a magnetic speed sensor is installed in each opening, and the gap between the magnetic speed sensor and the transmission housing is sealed with a flexible sealant;

[0034] S7: After confirming that the transmission is working properly, perform various operating condition tests on the transmission to be tested on the powertrain test bench or on the vehicle, and record the test results;

[0035] S8: Determine the working status of the planetary mechanism based on the test results.

[0036] From the structure of the existing automatic transmission Ravenna sun gear planetary mechanism, in the unrestricted state, we can know the speed of the sun gear or planetary carrier from the speed of the transmission shaft output shaft or input shaft. However, only one speed can be obtained.

[0037] Now let's take the example of a known planet carrier speed. When the planet carrier speed is known to be constant, the speed relationship between the sun gear and the ring gear is unknown because they are in unrestricted motion. At this time, if we can determine the speed of the sun gear or the ring gear, we can confirm the speed of the third component through the two speeds.

[0038] As the sun gear rotates inside, the conditions for installing the sensor at the core of the automatic transmission are quite bad, and it is impossible to directly test the sun gear speed. Therefore, the speed test can only be performed on the ring gear. According to the structural characteristics of the automatic transmission, the ring gear is located at the outermost layer inside the transmission housing. The rotation state of the ring gear can be detected by opening a hole in the transmission housing to determine the working state of the entire planetary mechanism.

[0039] S801: Obtain the rotation speed Nc of the planet carrier, in revolutions per minute (rpm);

[0040] S802: Obtain the rotation speed Nr of the ring gear, in revolutions per minute (rpm);

[0041] S803: Calculate the speed ratio i of the planetary mechanism according to the known parameters of the planetary mechanism:

[0042] i=(Zr+Zs) / Zs(1)

[0043] In formula (1):

[0044] Zr is the number of teeth on the ring gear;

[0045] Zs is the number of sun gear teeth;

[0046] S804: Calculate the rotation speed Ns of the sun gear in revolutions per minute (rpm):

[0047] Ns=(Nc+i·Nr) / (1+i)(2).

[0048] 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.

[0049] 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. A method for monitoring the operating status of a planetary mechanism of an automatic transmission, characterized in that: The method comprises the following steps: S1: disassemble the transmission to be tested and take out the ring gear of the planetary mechanism; S2: Make four evenly spaced points on the end face of the gear ring; S3: A magnetic sensor is installed at each point; S4: Perform hole opening processing on the transmission housing according to the digital model position; S5: Reinstall the ring gear and other parts obtained in S3 back into the transmission; S6: After confirming that the opening of the transmission housing can observe the magnet sensor, a magnetic speed sensor is installed in each opening, and the gap between the magnetic speed sensor and the transmission housing is sealed; S7: Perform various working condition tests on the transmission to be tested and record the test results; S8: Determine the working status of the planetary mechanism based on the test results.

2. The method for monitoring the operating status of a planetary mechanism of an automatic transmission according to claim 1, characterized in that: The S8 comprises the following steps: S801: Obtain the rotation speed Nc of the planet carrier; S802: Obtain the rotation speed Nr of the ring gear; S803: Calculate the speed ratio i of the planetary mechanism according to the known parameters of the planetary mechanism: i=(Zr+Zs) / Zs (1) In formula (1): Zr is the number of teeth on the ring gear; Zs is the number of sun gear teeth; S804: Calculate the rotation speed Ns of the sun gear: Ns=(Nc+i·Nr) / (1+i) (2).