Motor cavity airtightness detection system and method

Abstract

The invention relates to the technical field of motor sealing, in particular to a motor cavity airtightness detection system and method.The motor cavity airtightness detection system comprises an airtightness detection module, a damping induction module, a sealing execution module and a control module, and the airtightness detection module is used for detecting the gas pressure or leakage rate in a motor cavity; the damping sensing module is used for detecting the rotating damping torque of an output shaft of the motor in real time when the motor rotates; the sealing execution module is arranged at an outlet of the motor cavity, is used for executing a sealing adjustment action, and comprises a fixed base, a sealing element and a sealing adjustment assembly; the sealing adjusting assembly comprises a sealing adjusting ring capable of axially moving, and the movement of the sealing adjusting ring is used for changing the compression amount of the sealing piece. The control module is in communication connection with the air tightness detection module, the damping induction module and the sealing execution module. According to the invention, through multi-sensor fusion and closed-loop control, the problem of dynamic maintenance of motor sealing is solved.

Description

Technical Field

[0001] This invention relates to the field of motor sealing technology, and in particular to a motor cavity airtightness testing system and method. Background Technology

[0002] In industrial motors, especially those used in harsh environments such as underwater, outdoor, or clean environments, the sealing performance of their housings is crucial. Reliable sealing is a prerequisite for preventing the intrusion of moisture, dust, or harmful media, and for ensuring the long-term stable operation of internal electrical components and bearing mechanisms. Traditional seal design and maintenance mainly rely on static airtightness testing as the evaluation standard, and the compression of the seal is manually adjusted based on experience during assembly or maintenance.

[0003] However, static, offline detection and adjustment methods have significant limitations: First, they cannot reflect the dynamic decay of sealing performance caused by shaft rotation, temperature changes, and seal wear under actual operating conditions; second, to ensure a safety margin, operators often tend to over-compress the seals, leading to increased operating friction resistance, which not only causes additional energy loss and temperature rise, but also accelerates the abnormal wear of the seals and their contacts. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a motor cavity airtightness detection system and method that solves the dynamic maintenance problem of motor seals through multi-sensor fusion and closed-loop control.

[0005] The technical solution adopted in this invention is: a motor cavity airtightness detection system, including an airtightness detection module, a damping sensing module, a sealing execution module, and a control module. The airtightness detection module is used to detect the gas pressure or leakage rate inside the motor cavity; the damping sensing module is used to detect the rotational damping torque of its output shaft in real time when the motor rotates; the sealing execution module is located at the outlet of the motor cavity and is used to perform sealing adjustment actions, including a fixed base, a sealing element, and a sealing adjustment assembly; the sealing adjustment assembly includes an axially movable sealing adjustment ring, the movement of which is used to change the compression of the sealing element; the control module is communicatively connected to the airtightness detection module, the damping sensing module, and the sealing execution module respectively; the control module is configured to: receive feedback signals from the airtightness detection module and the damping sensing module, and generate control commands based on preset airtightness parameters and damping torque parameters to drive the sealing adjustment ring in the sealing execution module to move, thereby realizing dynamic detection and compensation of the sealing state of the motor cavity.

[0006] A further improvement to the above scheme is that the damping sensing module includes a torque sensor and / or a current detection unit. The torque sensor is installed on the motor output shaft or the transmission chain driving the load and is used to directly measure the axial damping torque. The current detection unit is electrically connected to the motor driver and is used to indirectly calculate the equivalent damping torque by detecting the real-time operating current of the motor and based on the torque constant of the motor.

[0007] A further improvement to the above solution is that the sealing adjustment component in the sealing execution module further includes an adjustment drive module, which is drivenly connected to the sealing adjustment ring; the control module precisely controls the axial displacement of the sealing adjustment ring by sending commands to the adjustment drive module.

[0008] A further improvement to the above solution is that the adjustment drive module is a micro stepper motor or a servo motor, one end of the sealing adjustment ring is provided with a connecting helical gear ring, and the drive end of the adjustment drive module is provided with a drive gear that meshes with the connecting helical gear ring, forming a gear transmission pair.

[0009] A further improvement to the above scheme is that the control module is configured to execute at least one of the following control modes: Static detection mode: When the motor is stationary, the air tightness detection module is activated to detect the air tightness of the cavity. If the detected value exceeds the preset range, the sealing execution module is controlled to perform compensation adjustment. Dynamic monitoring mode: When the motor is rotating, the damping sensing module is activated for real-time monitoring. If the damping torque value exceeds the reasonable range preset based on the current motor speed and load, it is determined that the seal is too tight or abnormally worn, triggering an early warning or shutdown command. Coordinated adjustment mode: Combining static airtightness test results with dynamic damping torque baseline, the target position of the sealing adjustment ring is comprehensively determined to achieve an optimized balance between sealing performance and rotational resistance.

[0010] A further improvement to the above solution is that the contact surface between the inner sealing lip of the seal and the sealing adjustment ring is a mutually cooperating slope structure and a conical abutment ring structure, and the seal is provided with a pressure-deformable extrusion cavity inside.

[0011] A further improvement to the above scheme is that the fixed base is provided with a sealing adjustment part, which is connected to the sealing adjustment ring through a threaded transmission pair; a sealing abutment step is also provided on one side of the sealing adjustment part, and a telescopic sealing ring for dynamically sealing the sealing adjustment ring is provided on the sealing abutment step.

[0012] A further improvement to the above scheme is that the airtightness detection module is an absolute pressure sensor or differential pressure sensor installed in the motor cavity to directly measure the pressure in the cavity; or, the leakage rate is indirectly calculated by injecting a quantitative test gas into the cavity through the control module and monitoring its pressure decay rate.

[0013] A detection method based on an airtightness testing system for motor cavities includes the following steps: Step S1: Control the motor to stop rotating, and obtain the initial airtightness parameters of the motor cavity through the airtightness detection module; Step S2: Control the motor to run at a preset speed under no-load or standard load conditions, monitor and record the rotational damping torque of its output shaft through the damping sensing module, and establish the dynamic damping torque baseline of the motor under good sealing conditions. Step S3: Compare the real-time detected air tightness parameters with the preset air tightness standard range, and compare the real-time detected dynamic damping torque with the dynamic damping torque baseline. In step S4, if the comparison result in S3 exceeds the allowable tolerance, the control module calculates the required compensation amount and drives the sealing execution module to adjust the axial position of the sealing adjustment ring to correct the sealing state.

[0014] A further improvement to the above scheme is that, in step S2, the specific method includes: when the sealing condition of the motor is confirmed to be good after factory debugging or overhaul, the motor is run at multiple different speed points, the stable damping torque value at each speed point is recorded, a speed-damping torque relationship curve is formed, and the curve is stored as a baseline.

[0015] A further improvement to the above scheme is that step S3 also includes trend prediction: continuously record the airtightness parameters and damping torque data of each test, analyze their changing trends over time, predict the rate of decay of sealing performance, and generate a pre-maintenance alarm before the performance deteriorates to the threshold requiring maintenance.

[0016] A further improvement to the above scheme is that step S4 follows the following principles: first, ensure the cavity sealing meets the standard based on the static airtightness test results; then, under the premise that the airtightness meets the standard, fine-tune the position of the sealing adjustment ring based on the dynamic damping torque data so that the operating resistance tends to the baseline value.

[0017] The beneficial effects of this invention are: Compared to existing motor cavity airtightness testing methods, this invention combines static airtightness testing with dynamic damping sensing to construct a dual-feedback mechanism. Static testing directly quantifies the final sealing result (whether there is leakage), while dynamic sensing monitors the health status of the seal under operating conditions in real time (changes in frictional resistance caused by wear and aging). The control module makes comprehensive decisions and compensation adjustments based on these two types of signals, improving the accuracy and reliability of sealing control. This invention, through a damping sensing module, can detect additional rotational resistance caused by excessive sealing in real time. The control system can automatically adjust the seal to the optimal position with minimal frictional resistance while ensuring airtightness meets standards. This reduces motor operating energy consumption, improves efficiency, and avoids abnormal wear of the seal caused by excessive compression, extending the service life of the seal and motor bearings. The control module drives the adjustment drive module to perform compensation actions, completely eliminating operational errors and uncertainties caused by manual adjustment. This ensures the accuracy of the compensation amount and the repeatability of the adjustment process, guaranteeing that the sealing performance can be restored to an optimal and consistent state regardless of the number of maintenance cycles, greatly improving product quality consistency and post-maintenance reliability. This invention solves the problem of dynamically maintaining the motor seal through multi-sensor fusion and closed-loop control, bringing comprehensive benefits such as improved energy efficiency and extended lifespan.

[0018] Based on the detection method of the motor cavity airtightness detection system, this invention combines static airtightness detection with dynamic damping baseline comparison. Static detection directly and accurately reflects the absolute barrier capability of the seal (whether there is leakage), while dynamic baseline comparison sensitively captures the health of the seal under operating conditions (changes in frictional resistance). This dual verification mechanism combining static and dynamic methods overcomes the limitations of single static detection in reflecting operational wear or single dynamic monitoring being susceptible to load / speed interference, achieving a more comprehensive and realistic assessment of sealing performance and significantly improving the reliability and accuracy of the detection results. In step S2, this invention establishes a unique dynamic damping torque baseline for each motor. This baseline is measured under its own "good sealing condition" and perfectly includes the motor's unique bearing resistance, assembly tolerances, and other background characteristics. Subsequent monitoring (S3) is compared with this personalized baseline, thereby highly sensitively and accurately identifying the damping increment caused by changes in sealing condition, greatly eliminating misjudgments, and enabling the effective detection of early and minor seal deterioration. This method links detection, analysis, decision-making, and execution into a complete automated process. It can autonomously diagnose faults, calculate precise compensation amounts, and drive the actuator to complete adjustment S4. The entire process requires no manual intervention, greatly reducing reliance on manpower and operator experience, while ensuring consistent and timely responses, achieving true intelligent operation and maintenance and proactive maintenance. This method can be executed periodically or before startup as a preventative maintenance measure, proactively identifying and eliminating potential sealing hazards to prevent problems before they occur. Simultaneously, by continuously monitoring the drift trend of the damping torque relative to its baseline (not just exceeding limits), the wear and aging rate of the seals can be predicted in advance, issuing early warnings before complete performance failure, thus achieving predictive maintenance. This invention's detection method, through dual verification combining static and dynamic methods, the establishment of individualized baselines, and the automated realization of a detection-decision-execution closed loop, greatly improves the accuracy and reliability of motor seal condition monitoring. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the internal structure of the motor of the present invention; Figure 2 for Figure 1 Enlarged diagram of point A in the diagram; Figure 3 This is a connection diagram of the motor cavity airtightness detection system of the present invention; Figure 4 This is a schematic flowchart of the detection method of the present invention.

[0020] Explanation of reference numerals in the attached drawings: 1. Air tightness detection module; 2. Damping sensing module; 3. Sealing execution module; 31. Fixed base; 311. Sealing adjustment part; 312. Sealing abutment step; 32. Sealing inner lip; 321. Extrusion chamber; 322. Sealing adjustment assembly; 33. Sealing adjustment ring; 34. Connecting helical tooth ring; 341. Adjustment drive module; 35. Drive gear; 351. Control module; 4. Motor cavity; 5. Detailed Implementation

[0021] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0022] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Figures 1-3As shown, in one embodiment of the present invention, a motor cavity airtightness detection system is provided, including an airtightness detection module 1, a damping sensing module 2, a sealing execution module 3, and a control module 4. The airtightness detection module 1 is used to detect the gas pressure or leakage rate inside the motor cavity; the damping sensing module 2 is used to detect the rotational damping torque of its output shaft in real time when the motor rotates; the sealing execution module 3 is disposed at the outlet of the motor cavity 5 and is used to perform sealing adjustment action, and includes a fixed base 31, a sealing element 32, and a sealing adjustment assembly 33; the sealing adjustment assembly 33 includes... The system includes an axially movable sealing adjustment ring 34, the movement of which changes the compression of the seal 32. The control module 4 is communicatively connected to the airtightness detection module 1, the damping sensing module 2, and the sealing execution module 3. The control module 4 is configured to receive feedback signals from the airtightness detection module 1 and the damping sensing module 2, and based on preset airtightness parameters and damping torque parameters, generate control commands to drive the sealing adjustment ring 34 in the sealing execution module 3, thereby achieving dynamic detection and compensation of the sealing state of the motor cavity 5. This embodiment combines static airtightness detection with dynamic damping sensing to construct a dual-feedback mechanism. Static detection directly quantifies the final sealing result (whether there is leakage), while dynamic sensing monitors the health status of the seal 32 in real time during operation (changes in frictional resistance due to wear and aging). The control module 4 makes comprehensive decisions and compensation adjustments based on these two types of signals, improving the accuracy and reliability of the sealing control. This embodiment, through the damping sensing module 2, can perceive in real time the additional rotational resistance caused by excessive sealing. The control system can automatically adjust the seal to the optimal position with minimal frictional resistance while ensuring airtightness. This reduces motor energy consumption, improves efficiency, and prevents abnormal wear of the seal 32 caused by excessive compression, extending the service life of both the seal 32 and the motor bearings. The compensation action is performed by driving the adjustment module through the control module 4, completely eliminating operational errors and uncertainties associated with manual adjustment. This ensures the accuracy of the compensation amount and the repeatability of the adjustment process, guaranteeing that the sealing performance can be restored to an optimal and consistent state regardless of the number of maintenance cycles, greatly improving product quality consistency and post-maintenance reliability. This embodiment solves the dynamic maintenance problem of motor seals through multi-sensor fusion and closed-loop control, bringing comprehensive benefits in terms of improved energy efficiency and extended lifespan.

[0024] The damping sensing module 2 includes a torque sensor and / or a current detection unit. The torque sensor is mounted on the motor output shaft or the drive chain of the load, and is used to directly measure the axial damping torque. The current detection unit is electrically connected to the motor driver and is used to indirectly calculate the equivalent damping torque based on the motor's torque constant by detecting the motor's real-time operating current. This embodiment provides flexibility and reliability by offering two optional damping sensing paths: a torque sensor and a current detection unit. The direct measurement method (torque sensor) mounted on the drive chain can obtain the most realistic and accurate axial damping torque signal, with strong anti-interference ability and high measurement accuracy, making it particularly suitable for applications with extremely high control precision requirements. The indirect calculation method (current detection unit) fully utilizes the current loop signal of the existing motor drive system, eliminating the need for additional mechanical sensors, achieving non-invasive detection, greatly reducing system complexity and hardware costs, and is particularly suitable for cost-sensitive and space-constrained applications.

[0025] The sealing adjustment component 33 in the sealing execution module 3 also includes an adjustment drive module 35, which is drivenly connected to the sealing adjustment ring 34. The control module 4 precisely controls the axial displacement of the sealing adjustment ring 34 by sending commands to the adjustment drive module 35. This embodiment, by introducing the adjustment drive module 35 driven by the control module 4, achieves automation and precision in the sealing compensation action. It replaces the traditional method of relying on manual adjustment, eliminating operational errors and uncertainties caused by human factors. The digital commands issued by the control module 4 can precisely control the movement stroke of the drive module, thereby achieving nanometer- or micrometer-level precise control of the axial displacement of the sealing adjustment ring 34.

[0026] The adjustment drive module 35 is a micro stepper motor or a servo motor. One end of the sealing adjustment ring 34 is provided with a connecting helical gear ring 341, and the drive end of the adjustment drive module 35 is provided with a drive gear 351 that meshes with the connecting helical gear ring 341, forming a gear transmission pair. This embodiment adopts a drive scheme of micro stepper / servo motor combined with gear-helical gear ring transmission pair, realizing efficient, precise and compact power transmission. The stepper or servo motor itself has precise positioning capability and self-locking characteristics, which can reliably maintain the adjusted position. The gear transmission method efficiently transmits the rotational motion of the motor to the sealing adjustment ring 34. At the same time, by selecting an appropriate gear reduction ratio, the output torque can be amplified, so that a small motor can generate a large enough thrust to overcome the frictional resistance of the seal 32, realizing the miniaturization of the actuator.

[0027] Control module 4 is configured to execute at least one of the following control modes: Static detection mode: When the motor is stationary, the air tightness detection module 1 is activated to detect the air tightness of the cavity. If the detected value exceeds the preset range, the sealing execution module 3 is controlled to perform compensation adjustment. Dynamic monitoring mode: When the motor is rotating, the damping sensing module 2 is activated for real-time monitoring. If the damping torque value exceeds the reasonable range preset based on the current motor speed and load, it is determined that the seal is too tight or abnormally worn, triggering an early warning or shutdown command. Coordinated adjustment mode: Combining static airtightness test results with dynamic damping torque baseline, the target position of the sealing adjustment ring 34 is comprehensively determined to achieve an optimized balance between sealing performance and rotational resistance.

[0028] This embodiment enables the system to flexibly handle various complex operating conditions and maximize its value by configuring multiple selectable intelligent control modes. The static detection mode focuses on the fundamentals, ensuring absolute seal integrity at critical points during equipment start-up and shutdown, suitable for applications requiring strict leak prevention. The dynamic monitoring mode acts like a tireless "sentinel," providing real-time health monitoring during equipment operation. If a surge in resistance due to an abnormality in seal 32 is detected, it can immediately trigger an alarm or shut down the system to prevent further damage and protect the core equipment. The collaborative adjustment mode represents the highest level of intelligence, integrating static and dynamic information; while ensuring leak-proof operation, it maximizes energy efficiency and extends equipment life.

[0029] The contact surfaces of the inner sealing lip 321 of the seal 32 and the sealing adjusting ring 34 are a mutually mating ramp structure and a conical abutment ring structure. The seal 32 has a pressure-deformable compression cavity 322 inside. In this embodiment, the mating structure of the ramp and conical abutment ring, combined with the internal compression cavity 322, constitutes a highly efficient and compliant force transmission and conversion mechanism. The mating ramps can convert the linear axial movement of the sealing adjusting ring 34 into radial expansion of the inner sealing lip 321, avoiding twisting or cutting damage to the sealing lip caused by sudden stress. The internal compression cavity 322 provides a larger radial deformation stroke, enabling a sealing effect to be achieved with only minor axial adjustments.

[0030] A sealing adjustment part 311 is provided on the fixed base 31. The sealing adjustment part 311 is connected to the sealing adjustment ring 34 through a threaded drive pair. A sealing abutment step 312 is also provided on one side of the sealing adjustment part 311. A telescopic sealing ring for dynamically sealing the sealing adjustment ring 34 is provided on the sealing abutment step 312. In this embodiment, the threaded drive pair connection realizes the precise guidance and self-locking function of the axial movement of the sealing adjustment ring 34. The threaded drive linearizes the rotational motion, and its inherent high mechanical benefits make the adjustment process both labor-saving and precise. More importantly, the threaded pair has good self-locking properties. Once the adjustment is completed, it can firmly maintain its position without the need for an additional braking device, ensuring the long-term stability of the sealing preload and preventing loosening due to vibration or other reasons.

[0031] The airtightness detection module 1 is an absolute pressure sensor or differential pressure sensor installed inside the motor cavity 5, used to directly measure the pressure inside the cavity; or, by injecting a quantitative test gas into the cavity through the control module 4 and monitoring its pressure decay rate, the leakage rate can be indirectly calculated. This embodiment provides two airtightness detection methods: direct pressure measurement and indirect leak detection, meeting the differentiated requirements of accuracy, cost, and response speed in different application scenarios. The direct measurement method (pressure sensor) has a fast response speed and can monitor minute changes in cavity pressure in real time, making it suitable for occasions requiring rapid feedback and continuous monitoring, and it is easy to install and integrate. Although the indirect leak detection method (gas filling and pressure holding method) requires an additional gas filling unit and has a slightly longer detection cycle, its detection accuracy is extremely high, capable of measuring extremely small leakage rates, and is suitable for sealing verification with extreme airtightness requirements (such as vacuum, flammable and explosive gas environments).

[0032] like Figures 1-4 As shown, a detection method based on a motor cavity airtightness detection system includes the following steps: Step S1: Control the motor to stop rotating and obtain the initial airtightness parameters of the motor cavity 5 through the airtightness detection module 1; Step S2: Control the motor to run at a preset speed under no-load or standard load, monitor and record the rotational damping torque of its output shaft through the damping sensing module 2, and establish the dynamic damping torque baseline of the motor under good sealing conditions; Step S3: Compare the real-time detected airtightness parameters with the preset airtightness standard range, and compare the real-time detected dynamic damping torque with the dynamic damping torque baseline; Step S4: If the comparison result in S3 exceeds the allowable tolerance, the control module 4 calculates the required compensation amount and drives the sealing execution module 3 to adjust the axial position of the sealing adjustment ring 34 to correct the sealing state.

[0033] This embodiment combines static airtightness testing with dynamic damping baseline comparison. Static testing directly and accurately reflects the absolute barrier capability of the seal (whether there is leakage), while dynamic baseline comparison sensitively captures the health of the seal 32 under operating conditions (changes in frictional resistance). This dual verification mechanism combining static and dynamic testing overcomes the limitations of single static testing failing to reflect operational wear or single dynamic monitoring being susceptible to load / speed interference, achieving a more comprehensive and realistic assessment of sealing performance and significantly improving the reliability and accuracy of the test results. In step S2, the method of this invention establishes a unique dynamic damping torque baseline for each motor. This baseline is measured under its own "good sealing condition" and perfectly encompasses the motor's unique bearing resistance, assembly tolerances, and other background characteristics. Subsequent monitoring (S3) compares the results with this personalized baseline, thereby highly sensitively and accurately identifying the damping increment caused by changes in sealing condition, greatly eliminating misjudgments, and enabling effective detection of early, minor seal deterioration. This method integrates detection, analysis, decision-making, and execution into a complete automated process. It can autonomously diagnose faults, calculate precise compensation amounts, and drive the actuator to complete adjustment S4. The entire process requires no manual intervention, greatly reducing reliance on manpower and operator experience, while ensuring consistent and timely responses, achieving true intelligent operation and maintenance and proactive maintenance. This method can be executed periodically or before startup as a preventative maintenance measure, proactively identifying and eliminating potential sealing hazards to prevent problems before they occur. Simultaneously, by continuously monitoring the drift trend of the damping torque relative to its baseline (not just exceeding limits), the wear and aging rate of the seal 32 can be predicted in advance, issuing early warnings before complete performance failure, thus achieving predictive maintenance. The detection method in this embodiment, through dual verification combining static and dynamic methods, the establishment of individualized baselines, and the automated realization of a detection-decision-execution closed loop, greatly improves the accuracy and reliability of motor seal condition monitoring.

[0034] In step S2, the specific method includes: after the motor's sealing condition is confirmed to be good following factory testing or overhaul, the motor is run at multiple different speed points, and the stable damping torque value at each speed point is recorded to form a speed-damping torque relationship curve, which is then stored as a baseline. This embodiment establishes a speed-damping torque relationship curve as a dynamic baseline by running the motor at different speed points after its sealing condition is confirmed to be good following factory testing or overhaul, and recording the stable damping torque value at each speed. The damping torque itself changes with the speed, and a baseline at a single speed point cannot represent the entire operating condition. This method, by establishing a continuous relationship curve, provides a high-resolution, accurate reference coordinate system covering the entire operating speed range for subsequent condition monitoring. This ensures that at any operating speed, the system can find the corresponding and most accurate benchmark value for comparison, completely eliminating the risk of misjudgment caused by speed fluctuations.

[0035] Step S3 also includes trend prediction: continuously recording the airtightness parameters and damping torque data for each test, analyzing their changing trends over time, predicting the rate of deterioration of sealing performance, and generating a pre-maintenance alarm before the performance deteriorates to the threshold requiring maintenance. This embodiment, by introducing a trend prediction algorithm in step S3, can continuously record and analyze historical data on airtightness parameters and dynamic damping torque. Through machine learning or data fitting algorithms, the rate of deterioration and degradation trend of sealing performance (such as a slow increase in leakage rate or a gradual increase in frictional resistance) can be accurately calculated. This allows the system to accurately predict potential fault points and generate pre-maintenance alarms long before the sealing performance completely fails, leading to downtime or secondary damage.

[0036] Step S4 follows these principles: Prioritize ensuring the cavity's sealing meets standards based on static airtightness test results; once airtightness is achieved, fine-tune the position of the sealing adjustment ring 34 based on dynamic damping torque data to bring the operating resistance closer to the baseline value. This embodiment achieves a balance between sealing reliability and economy. First, ensuring static airtightness is a non-negotiable prerequisite and primary adjustment target, ensuring the most basic protective functions of the motor cavity 5 (such as waterproofing, dustproofing, and pressure holding) are absolutely satisfied, fundamentally eliminating the core risks of media leakage, internal component contamination, or corrosion due to insufficient sealing. After ensuring this fundamental safety baseline, the system then initiates dynamic damping torque fine-tuning, aiming to optimize the operating resistance to an ideal state close to the healthy baseline value.

[0037] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A motor cavity airtightness detection system, characterized in that: The system includes an airtightness detection module, a damping sensing module, a sealing execution module, and a control module. The airtightness detection module detects the gas pressure or leakage rate within the motor cavity. The damping sensing module detects the rotational damping torque of the output shaft in real time when the motor rotates. The sealing execution module, located at the outlet of the motor cavity, performs sealing adjustment actions and includes a fixed base, a sealing element, and a sealing adjustment assembly. The sealing adjustment assembly includes an axially movable sealing adjustment ring, the movement of which changes the compression of the sealing element. The control module is communicatively connected to the airtightness detection module, the damping sensing module, and the sealing execution module. The control module is configured to receive feedback signals from the airtightness detection module and the damping sensing module, and based on preset airtightness parameters and damping torque parameters, generate control commands to drive the sealing adjustment ring in the sealing execution module, thereby achieving dynamic detection and compensation of the sealing state of the motor cavity.

2. The motor cavity airtightness detection system according to claim 1, characterized in that: The damping sensing module includes a torque sensor and / or a current detection unit. The torque sensor is installed on the motor output shaft or the transmission chain driving the load and is used to directly measure the axial damping torque. The current detection unit is electrically connected to the motor driver and is used to indirectly calculate the equivalent damping torque by detecting the real-time operating current of the motor and based on the torque constant of the motor.

3. The motor cavity airtightness detection system according to claim 1, characterized in that: The sealing adjustment component in the sealing execution module further includes an adjustment drive module, which is drivenly connected to the sealing adjustment ring; the control module precisely controls the axial displacement of the sealing adjustment ring by sending commands to the adjustment drive module.

4. The motor cavity airtightness detection system according to claim 3, characterized in that: The adjustment drive module is a micro stepper motor or a servo motor. One end of the sealing adjustment ring is provided with a connecting helical tooth ring, and the drive end of the adjustment drive module is provided with a drive gear that meshes with the connecting helical tooth ring, forming a gear transmission pair.

5. The motor cavity airtightness detection system according to claim 1, characterized in that: The control module is configured to execute at least one of the following control modes: Static detection mode: When the motor is stationary, the air tightness detection module is activated to detect the air tightness of the cavity. If the detected value exceeds the preset range, the sealing execution module is controlled to perform compensation adjustment. Dynamic monitoring mode: When the motor is rotating, the damping sensing module is activated for real-time monitoring. If the damping torque value exceeds the reasonable range preset based on the current motor speed and load, it is determined that the seal is too tight or abnormally worn, triggering an early warning or shutdown command. Coordinated adjustment mode: Combining static airtightness test results with dynamic damping torque baseline, the target position of the sealing adjustment ring is comprehensively determined to achieve an optimized balance between sealing performance and rotational resistance.

6. The motor cavity airtightness detection system according to claim 1, characterized in that: The inner sealing lip of the seal and the contact surface of the sealing adjustment ring are a mutually cooperating slope structure and a conical abutment ring structure, and the seal has a pressure-deformable extrusion cavity inside.

7. The motor cavity airtightness detection system according to claim 1, characterized in that: The fixed base is provided with a sealing adjustment part, which is connected to the sealing adjustment ring through a threaded drive pair; a sealing abutment step is also provided on one side of the sealing adjustment part, and a telescopic sealing ring for dynamically sealing the sealing adjustment ring is provided on the sealing abutment step.

8. The motor cavity airtightness detection system according to claim 1, characterized in that: The airtightness detection module is an absolute pressure sensor or differential pressure sensor installed in the motor cavity, used to directly measure the pressure in the cavity; or, the leakage rate is indirectly calculated by injecting a quantitative test gas into the cavity through the control module and monitoring its pressure decay rate.

9. A detection method based on the motor cavity airtightness detection system according to any one of claims 1 to 8, characterized in that: Includes the following steps: Step S1: Control the motor to stop rotating, and obtain the initial airtightness parameters of the motor cavity through the airtightness detection module; Step S2: Control the motor to run at a preset speed under no-load or standard load conditions, monitor and record the rotational damping torque of its output shaft through the damping sensing module, and establish the dynamic damping torque baseline of the motor under good sealing conditions. Step S3: Compare the real-time detected air tightness parameters with the preset air tightness standard range, and compare the real-time detected dynamic damping torque with the dynamic damping torque baseline. In step S4, if the comparison result in S3 exceeds the allowable tolerance, the control module calculates the required compensation amount and drives the sealing execution module to adjust the axial position of the sealing adjustment ring to correct the sealing state.

10. The detection method according to claim 9, characterized in that: In step S2, the specific method includes: when the sealing condition of the motor is confirmed to be good after factory debugging or overhaul, the motor is run at multiple different speed points, the stable damping torque value at each speed point is recorded, a speed-damping torque relationship curve is formed, and the curve is stored as a baseline. Step S3 also includes trend prediction: continuously record the air tightness parameters and damping torque data of each test, analyze their changing trends over time, predict the rate of deterioration of sealing performance, and generate a pre-maintenance alarm before the performance deteriorates to the threshold requiring maintenance. In step S4, the following principles are followed: First, ensure that the cavity sealing meets the standard based on the static airtightness test results; on the premise that the airtightness meets the standard, then fine-tune the position of the sealing adjustment ring based on the dynamic damping torque data so that the operating resistance tends to the baseline value.

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