Aero high-pressure wobble-plate compressor jounal bearing life test system and test method

Abstract

The application belongs to the technical field of compressors, and discloses a kind of aviation high-pressure swing disc compressor articulation bearing life test system and test method, and the main structure of test system includes driving system, core test system and loading system.Driving system is located in front section, is connected with core test system and drives core test system;Loading system is located at the end, is connected with core test system and provides dynamic periodic change load.Test method is based on this test bench, under the condition of controlling certain speed and load, measures the temperature signal change and vibration signal change of articulation bearing, reflects the degradation and failure condition of articulation bearing.The application can realize articulation friction pair wear test under any speed by stepless speed regulation, realize the same bearing movement condition with actual movement characteristics, realize high-frequency reciprocating articulation bearing dynamic supply load, and also can realize real-time temperature measurement and vibration measurement of articulation bearing under high-frequency reciprocating motion, provide quick evaluation reference for wear state and failure of articulation friction pair.

Description

Technical Field

[0001] This invention belongs to the field of compressor technology, specifically relating to a test system and method for testing the life of joint bearings in an aerospace high-pressure swivel compressor. Background Technology

[0002] A swaying disc compressor is a type of compressor with a unique structure. Due to its compact design and high stability, it is frequently used in high-pressure gas supply systems in the aerospace industry. The spherical bearing at the swaying disc end is a key component for the transmission of the swaying disc compressor, located at the connection between the swaying disc and the connecting rod. During operation, the swaying disc oscillates periodically, driving the connecting rod and piston to reciprocate periodically through the spherical bearing structure, thereby compressing the gas within the cylinder.

[0003] Rapid wear and short lifespan of the spherical bearings in aerospace high-pressure swivel compressors have always been key issues restricting compressor performance stability. Due to the high discharge pressure ratio of the compressor and the large combined piston force at each stage, the contact pressure between the spherical friction pairs is high. Furthermore, the use of grease lubrication makes maintaining the lubrication film difficult, resulting in less than ideal lubrication. Therefore, spherical bearing wear is often severe, with a lifespan shorter than expected, sometimes even exhibiting severe wear accompanied by grease carbonization and seizing.

[0004] Due to the complex motion characteristics and periodically changing load features of the swashplate mechanism, existing spherical bearing wear testing machines, both domestically and internationally, cannot achieve the required experimental conditions. On the one hand, the motion state of the spherical friction pairs in the swashplate compressor is complex, and existing testing machines cannot simulate similar motion states. On the other hand, the load on the spherical compressor's spherical friction pairs changes rapidly and periodically with the compression process, while existing testing machines can only achieve constant load conditions. Therefore, the study of wear and failure of spherical bearings in aerospace high-pressure swashplate compressors lacks corresponding experimental conditions, which brings difficulties to the design, analysis, and verification of spherical bearings. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention aims to propose a life test system and method for the spherical bearing of an aerospace high-pressure swivel compressor. The present invention can simulate the motion state and periodically changing extreme load conditions of the actual swivel end spherical bearing, and obtain the temperature and vibration information of the spherical bearing in real time. Based on the temperature and vibration signals, the degradation and failure of the bearing can be analyzed, thereby achieving more accurate wear analysis and life prediction.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A life testing system for the joint bearing of an aviation high-pressure swivel compressor includes a drive system, a core testing system, and a loading system;

[0008] The core testing system includes a wedge-shaped drive disk, a pendulum disk, a joint bearing assembly, and a connecting rod assembly. The drive system is connected to the wedge-shaped drive disk and can drive the wedge-shaped drive disk to rotate. The pendulum disk is slidably connected to the inclined surface of the wedge-shaped drive disk. The pendulum disk is connected to an anti-rotation structure to prevent self-rotation. When the drive system drives the wedge-shaped drive disk to rotate, the drive system drives the wedge-shaped drive disk to move through its inclined surface. One end of the joint bearing assembly is installed at a non-central position of the pendulum disk, and the other end of the joint bearing assembly is connected to one end of the connecting rod assembly. A temperature sensor is provided on the joint bearing assembly, and a vibration sensor is provided on the connecting rod assembly.

[0009] The loading system includes a fisheye bearing and a loading spring assembly. The other end of the connecting rod assembly is connected to one end of the fisheye bearing, and the other end of the fisheye bearing is connected to one end of the loading spring assembly. The other end of the loading spring assembly is fixed. A force sensor is provided at the connection between the fisheye bearing and the loading spring assembly.

[0010] Preferably, the drive system includes a drive motor, the output shaft of which is connected to the rotation center of the wedge drive disk and can drive the wedge drive disk to rotate; the output shaft of the drive motor is equipped with a torque measuring instrument for measuring the torque at the power input end of the wedge drive disk and a speed measuring instrument for measuring the rotational speed at the power input end of the wedge drive disk.

[0011] Preferably, a speed reducer is provided between the output shaft of the drive motor and the wedge-shaped drive disk, wherein the output shaft of the drive motor is connected to the input end of the speed reducer, the output end of the speed reducer is connected to the rotation center of the wedge-shaped drive disk, and the torque measuring instrument and the speed measuring instrument are located at the output end of the speed reducer.

[0012] Preferably, the spherical bearing assembly includes: a spherical bearing mounting hole on the spherical plate; a spherical bearing mounting threaded hole surrounding the spherical bearing mounting hole and on the spherical plate; a spherical bearing socket embedded in the spherical bearing mounting hole, forming a joint pair with the spherical bearing ball head; a spherical bearing ball head, which is a detachable structure and connected to the connecting rod assembly via a spherical bearing ball head connecting threaded rod; and a spherical bearing fixing plate fixed on the spherical plate by mounting screws and the spherical bearing mounting threaded hole, used to restrict the spherical bearing ball socket.

[0013] Preferably, the mounting screw has a mounting hole for mounting a temperature sensor.

[0014] Preferably, a pad with an ear is provided between the joint bearing fixing plate and the mounting screw, and the wire of the temperature sensor is fixed to the ear of the pad with an ear.

[0015] Preferably, the connecting rod assembly includes a connecting rod assembly connector, which is threadedly connected to the ball joint connecting thread rod of the spherical bearing.

[0016] The connecting rod assembly connector is provided with a vibration sensor mounting threaded hole for mounting a miniature piezoelectric vibration sensor; a connecting rod anti-rotation rope threaded hole for limiting the rotation of the connecting rod assembly; and a connecting rod assembly connecting thread for connecting a fisheye bearing.

[0017] The fisheye bearing includes a fisheye bearing assembly. One end of the fisheye bearing assembly is connected to the connecting rod assembly via a connecting threaded sleeve. The other end of the fisheye bearing assembly is connected to the loading system via a fisheye bearing connecting thread. The force sensor is disposed between the fisheye bearing connecting thread and the loading system.

[0018] Preferably, the stiffness and pre-compression of the loading spring assembly are adjustable, and the unidirectional stroke of the reciprocating motion of the loading spring assembly is... s At that time, by adjusting the spring stiffness K I and pre-compression amount Δ L I The combined piston force of each stage of the actual compressor F NI Time satisfies F I-min = K I Δ L I = F NI-min , F I-max = K I (Δ) L I +s )= F NI-max This is to simulate the periodic changes in piston force in an actual compressor.

[0019] This invention also provides a method for testing the life of a spherical bearing in an aerospace high-pressure oscillating compressor. This method utilizes the testing system described above and includes the following steps:

[0020] The speed control is made consistent with that of the actual compressor by adjusting the drive system. The drive system drives the wedge drive disk to rotate, the wedge drive disk drives the swing disk to swing, and during the swing of the swing disk, the joint bearing assembly moves with the swing disk and can drive the loading spring assembly to reciprocate through the connecting rod assembly and the fisheye bearing.

[0021] Dynamic periodic loads are simulated by loading spring assemblies, and detection data from force sensors, temperature sensors, and vibration sensors are collected in real time.

[0022] The degradation and failure of the joint bearing assembly are analyzed using detection data from force sensors, temperature sensors, and vibration sensors.

[0023] Preferably, the data acquisition frequency of the vibration sensor is ≥10kHz, and the spectral characteristics and peak fluctuations are obtained based on the detection data of the vibration sensor.

[0024] The logic for judging the degradation and failure of spherical bearing assemblies by analyzing detection data from force sensors, temperature sensors, and vibration sensors includes:

[0025] Stable phase: Temperature fluctuation range is within T 0± T a Within the range, and T 0< T 1 T s The peak vibration fluctuation range is within A 0± A a Within the range and the spectral amplitude fluctuation is less than K a , T a To allow for temperature fluctuations during the stable phase T 1 represents the critical failure temperature. T s For temperature safety threshold, A 0 represents the stable mean value of the vibration peak value. A a To allow for amplitude fluctuations during the stable phase of the vibration peak. K a This is the allowable fluctuation range of amplitude at each frequency during the stable phase.

[0026] Degradation stage: Temperature continues to exceed T 0+ T k Or the peak vibration level continues to exceed A 0+ A k or the spectral amplitude fluctuation exceeds K a ;in, T k The threshold for determining degradation A k The threshold for determining degradation;

[0027] Failure stage: Temperature reaches the critical failure value T 1 or the vibration peak value reaches the failure threshold. A 1.

[0028] Compared with the prior art, the present invention has the following beneficial technical effects:

[0029] The main structure of the aerospace high-pressure oscillating compressor joint bearing life testing system of this invention includes a drive system, a core testing system, and a loading system. The drive system is located at the front, connected to and driving the core testing system; the loading system is located at the end, connected to the core testing system, and provides dynamically changing periodic loads. This invention can achieve joint friction pair wear testing at arbitrary speeds through stepless speed regulation of the drive system, realizing bearing motion conditions identical to actual motion characteristics, and achieving dynamic loading of the joint bearing under high-frequency reciprocating motion. This invention can also achieve real-time temperature and vibration measurement of the joint bearing under high-frequency reciprocating motion, analyzing its degradation and failure based on temperature and vibration signals, providing a rapid assessment reference for the wear state and failure of the joint friction pair. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the life test system for the joint bearing of the high-pressure oscillating compressor of the present invention.

[0031] Figure 2 This is a schematic diagram of the installation relationship of the spherical bearing assembly used in an embodiment of the present invention.

[0032] Figure 3 This is a schematic diagram of the installation relationship of the connecting rod assembly used in an embodiment of the present invention.

[0033] In the diagram, A-drive system, A1-drive motor, A2-reducer, A3-torque meter, A4-speed meter;

[0034] B - Core testing system, B1 - Wedge drive disk, B11 - Inclined surface, B2 - Swing disk, B3 - Spherical bearing assembly, B301 - Swing disk spherical bearing mounting hole, B302 - Spherical bearing mounting threaded hole, B303 - Spherical bearing ball socket, B304 - Spherical bearing ball head, B3041 - Spherical bearing ball head connecting threaded rod, B305 - Spherical bearing fixing plate, B306 - With ear washer, B307 - Mounting screw, B4 - Temperature sensor, B5 - Vibration sensor, B501 - Miniature piezoelectric vibration sensor, B502 - Vibration sensor mounting thread, B6 - Linkage assembly, B601 - Vibration sensor mounting threaded hole, B602 - Linkage anti-rotation rope hole, B603 - Linkage assembly connecting thread, B604 - Linkage assembly connecting seat;

[0035] C - Loading system, C1 - Fisheye bearing, C101 - Connecting threaded sleeve, C102 - Fisheye bearing assembly, C103 - Fisheye bearing connecting thread, C2 - Force sensor, C3 - Loading spring assembly. Detailed Implementation

[0036] The present invention will be further described clearly and in detail below with reference to specific embodiments and the accompanying drawings. Those skilled in the art will be able to implement the present invention based on these descriptions. Furthermore, the embodiments of the present invention described below are generally only some, not all, of the embodiments of the present invention. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0037] This embodiment details a life testing system for aerospace high-pressure oscillating compressor spherical bearings. This testing system aims to evaluate the durability performance of spherical bearings under high-load, reciprocating motion conditions by precisely controlling and monitoring key parameters. The aerospace high-pressure oscillating compressor spherical bearing life testing system consists of three main modules: a drive system A, a core testing system B, and a loading system C. These modules work together to complete the test. Figure 1 As shown.

[0038] The drive system A provides the power required for the test (directly driving the core test system B) and accurately measures the transmitted torque and speed, providing a controllable input to the core test system. The drive system A consists of a drive motor A1, a reducer A2, a torque meter A3, and a speed meter A4. The drive motor A1 provides power and is selected for its stable speed output and sufficient torque capacity. The motor shaft is machined with a keyway or connected via a coupling to the input shaft of the reducer A2, ensuring reliable power transmission. The reducer A2 reduces the output speed and increases the torque, and is selected for its appropriate reduction ratio and load-bearing capacity. The reducer's input end is connected to the output shaft of the drive motor A1 via a keyway or coupling, and its output end is connected to the input end of the torque meter A3 via a keyway or coupling. The reducer's function is to reduce the drive motor's output speed while increasing torque to meet the low-speed, high-torque requirements of the test. The torque meter A3 measures the output torque and is a high-precision instrument with sufficient measurement range and accuracy. The input end of the torque measuring instrument is connected to the output end of the reducer A2 via a keyway or coupling, and its output end is connected to the input end of the speed measuring instrument A4 via a keyway or coupling. The torque measuring instrument measures the torque value transmitted to the core test system in real time, providing a basis for data analysis. The speed measuring instrument A4 is used to measure the output speed, and a speed measuring instrument with sufficient accuracy and response speed is selected. The input end of the speed measuring instrument is connected to the output end of the torque measuring instrument A3 via a keyway or coupling, and its output end is directly or indirectly connected to the core test system to measure the speed of the core test system and can be used as a feedback signal for the control system.

[0039] The core testing system B is used to realize the reciprocating oscillating motion of the spherical plain bearing, provide the installation and fixation of the spherical plain bearing, and monitor temperature and vibration parameters.

[0040] The core test system B comprises a wedge-shaped drive disk B1, a swing disk B2, a spherical bearing assembly B3, a temperature sensor B4, a vibration sensor B5, and a connecting rod assembly B6. The wedge-shaped drive disk B1 is made of high-strength, wear-resistant material. (See attached image.) Figure 1 The overall shape of the wedge-shaped drive disk B1 is such that one end face is an inclined plane B11 ( Figure 1 The right side of the wedge-shaped drive disk B1 shown), and the other end face ( Figure 1 The left side of the wedge-shaped drive disk B1 shown is a cylindrical shape perpendicular to the axis, and the bottom of the wedge-shaped drive disk B1 (i.e., Figure 1 The wedge-shaped drive disk B1 shown has a mounting hole or bearing seat at its center on the left side, which is connected to the drive shaft (i.e., the output shaft of the tachometer A4) via a bearing. The right side of the wedge-shaped drive disk B1 has an inclined protrusion structure, which is connected to the bottom of the swing disk B2 (i.e., the...) via a bearing. Figure 1 The left side of the wedge-shaped drive disk B1 (as shown) contacts the wedge-shaped drive disk B2, forming a sliding surface (i.e., the wedge-shaped drive disk and the wedge-shaped drive disk B1 are slidably connected). The rotational motion of the wedge-shaped drive disk B1 is converted into the oscillating motion of the wedge-shaped drive disk B2. Lubricating oil or grease is applied to the contact surface between the wedge-shaped drive disk B1 and the wedge-shaped drive disk B2 to reduce friction and wear. The wedge-shaped drive disk B2 is made of high-strength material, with sufficient rigidity and stability. The bottom of the wedge-shaped drive disk B2 is provided with a groove or bearing seat that mates with the wedge-shaped drive disk B1, allowing the wedge-shaped drive disk B2 to oscillate around the inclined sliding surface (i.e., inclined surface B11) of the wedge-shaped drive disk B1. The wedge-shaped drive disk is connected with an anti-rotation structure to prevent self-rotation. Specifically, anti-rotation rollers are also installed at the bottom of the wedge-shaped drive disk. These rollers are confined within a guide groove of a frame, thus ensuring that the wedge-shaped drive disk can only oscillate back and forth and cannot rotate on its own. Multiple spherical bearing mounting holes B301 are machined on the wedge-shaped drive disk for mounting multiple spherical bearing assemblies B3. The mounting relationship of the spherical bearing assemblies B3 is as follows: Figure 2The spherical plain bearing assembly B3 is used to support and test the spherical plain bearing under test. One end of the spherical plain bearing assembly B3 is installed at a non-central position on the oscillating plate B2, meaning that multiple spherical plain bearing assemblies B3 are distributed around the center of the oscillating plate B2, and multiple spherical plain bearing assemblies B3 are located on the same circumference. The spherical plain bearing mounting hole B301 is machined on the oscillating plate B2 to provide installation space for the spherical plain bearing ball socket B303. The shape and size of the mounting hole precisely match the ball socket B303 to ensure that the ball socket can be stably embedded. The spherical plain bearing mounting threaded hole B302 is machined on the oscillating plate B2 around the spherical plain bearing mounting hole B301 and is used to install the mounting screw B307 of the spherical plain bearing fixing plate B305. The spherical plain bearing ball socket B303 is made of wear-resistant material, and its shape matches the spherical plain bearing mounting hole B301 on the oscillating plate. It has a smooth spherical groove inside to mate with the spherical plain bearing ball head B304. The spherical plain bearing ball head B304 is made of high-strength wear-resistant material and forms a joint pair with the spherical plain bearing ball socket B303. The short rod at the tail end of the spherical plain bearing ball joint B304 (i.e., the threaded rod B3041 connecting the spherical plain bearing ball joint) has threads for detachable connection with the connecting rod assembly B6. The spherical plain bearing retaining plate B305 is used to press the spherical plain bearing ball socket B303, fixing it within the mounting hole B301 of the oscillating plate. The spherical plain bearing retaining plate B305 has multiple holes aligned with the spherical plain bearing mounting threaded holes B302 of the oscillating plate. A lug washer B306 is located between the retaining plate B305 and the mounting screw B307 to increase the clamping force of the mounting screw, preventing it from loosening. The lug of the lug washer B306 is also bent to hold the wire of the temperature sensor. The mounting screw B307 is used to secure the spherical plain bearing retaining plate B305. The temperature sensor B4 is used to measure the temperature near the spherical plain bearing assembly (B3). The temperature sensor B4 uses a thermocouple or thermistor sensor, selecting a model with fast response and high measurement accuracy. On the display plate, a through hole is machined near the ball joint socket B303 of the spherical plain bearing for inserting a temperature sensor. Two temperature sensors are inserted near each spherical plain bearing to improve the reliability of temperature measurement. Specifically, a mounting hole for installing a temperature sensor B4 can be made on the mounting screw B307, and the temperature sensor B4 is inserted into the mounting hole. Two mounting screws B307 are symmetrically arranged on each spherical plain bearing fixing plate B305. The temperature sensor is connected to the data acquisition system to monitor the temperature change of the spherical plain bearing in real time. Its wire is clamped in the ear with ear pad B306. The wire near the temperature measuring head of the temperature sensor B4 has strong resilience, and the restoring force when bent can stabilize it in the temperature measuring hole. The part near the temperature measuring head of the sensor has a certain degree of resilience, and the restoring force generated when bent can stabilize the temperature measuring head in the temperature measuring hole.

[0041] Linkage assembly B6, used to transmit motion and load, is made of high-strength material and possesses sufficient rigidity and bending strength. The installation relationship of linkage assembly B6 is as follows: Figure 3 The linkage assembly includes a linkage assembly connector B604, one end of which ( Figure 3 The left end shown has a connecting thread (specifically a threaded hole) for threaded connection with the ball joint connecting thread rod B3041 of the ball joint of the spherical bearing B304, and the other end of the connecting rod assembly connecting seat B604 ( Figure 3 The right end (as shown) is provided with a connecting thread B603 for the connecting rod assembly. The connecting thread B603 is detachably connected to the connecting threaded sleeve C101 and the fisheye bearing assembly C102. The connecting rod assembly connecting seat B604 has a threaded hole B601 for mounting a vibration sensor B5, and a rope-passing hole B602 to prevent the connecting rod from rotating. The vibration sensor mounting threaded hole B601 is used to mount the vibration sensor B5. The vibration sensor B5 is used to measure vibration; a miniature piezoelectric vibration sensor B501 is selected, which features small size, light weight, and high sensitivity. One vibration sensor is mounted on each connecting rod assembly B6 to measure the vibration during the connecting rod's movement. The vibration sensor is threaded into the threaded hole B601 on the connecting rod assembly and connected to a data acquisition system to monitor the vibration of the connecting rod in real time. The vibration sensor mounting thread B502 is used to connect the miniature piezoelectric vibration sensor B501. The connecting rod anti-rotation rope-passing hole B602 is used to connect an anti-rotation rope to prevent the connecting rod assembly B6 from rotating.

[0042] The threaded sleeve C101 connects the connecting rod assembly B6 and the fisheye bearing assembly C102. Both ends of the threaded sleeve C101 are threaded interfaces. The outer ring of the fisheye bearing assembly C102 has threads and is used to connect with the threaded sleeve C101. The inner ring of the fisheye bearing assembly C102 has a joint for connecting the fisheye bearing C102. The fisheye bearing connecting thread C103 is used to connect the fisheye bearing assembly C102.

[0043] The loading system C applies a dynamically and periodically changing load to the spherical bearing to simulate the actual load conditions when the compressor is working. The load application direction of the loading system C is linked to the motion direction of the core test system B.

[0044] The loading system C comprises a fisheye bearing C1, a force sensor C2, and a loading spring assembly C3. The fisheye bearing C1 is selected to have sufficient load-bearing capacity and rotation angle. Its inner ring is connected to the end of the connecting rod assembly B6 via a threaded connection B603, and its outer ring is connected to the force sensor C2 via a thread. The force sensor C2 is a high-precision force sensor with sufficient measurement range and accuracy. The front end of the force sensor is connected to the fisheye bearing C1 via a thread, and the rear end is connected to the loading spring assembly C3. The force sensor measures the load on the spherical bearing in real time and transmits the data to the data acquisition system. The loading spring assembly C3 is a spring assembly with specific stiffness and deformation. One end of the spring assembly is connected to the force sensor C2, and the other end is fixed to the frame. The pre-compression and stiffness of the spring can be adjusted, thereby controlling the load applied to the spherical bearing. By adjusting the loading spring assembly, the dynamic load on the spherical bearing under actual working conditions can be simulated.

[0045] See Figure 1 In the above scheme, each joint bearing assembly B3 is connected to a connecting rod assembly B6, a fisheye bearing C1, and a loading spring assembly C3.

[0046] The working principle of the experimental system in this embodiment is as follows:

[0047] Drive motor A1 outputs power through reducer A2. Adjusting drive motor A1 achieves speed control consistent with the actual compressor. Reducer A2 drives wedge-shaped drive disc B1 to rotate. The rotational motion of the wedge-shaped drive disc is transmitted to the swing disc B2 via bearing lubrication, causing the swing disc to oscillate reciprocally. The oscillation of the swing disc is transmitted to the loading system C through spherical bearing assembly B3 and connecting rod assembly B6. In the loading system, fisheye bearing C1 is connected to force sensor C2 and interacts with loading spring assembly C3, generating periodic load changes to simulate the actual working environment of the spherical bearing. Temperature sensor B4 and vibration sensor B5 monitor the temperature and vibration data of the spherical bearing in real time. The data acquisition system collects all measurement data for analyzing the lifespan of the spherical bearing.

[0048] The test methods based on this test system include operating condition setting methods, temperature signal-based analysis methods for joint bearing degradation and failure, and vibration signal-based analysis methods for joint bearing degradation and failure.

[0049] Operating condition settings include speed settings and load settings. The speed n of the oscillating plate B2 should be consistent with the actual speed of the oscillating plate compressor, and the loads of each joint should be set accordingly. F I It should be provided by spring force, by adjusting the spring stiffness. K I and pre-compression amount Δ L I To achieve the integrated piston force of each stage of the actual compressor.F NI Corresponding, satisfying F I-min = K I Δ L I = F NI-min , F I-max = K I (Δ) L I +s )= F NI-max In the formula s It is the unidirectional stroke of the spring's reciprocating motion.

[0050] The method for analyzing joint bearing degradation and failure based on temperature signals is as follows: the temperature signal measurement interval is no more than 1 second, and the temperature of each joint is taken as the average value of the measurements from two corresponding temperature sensors. The temperature judgment criteria for joint degradation and failure are as follows: during the stable phase, after power-on, the joint temperature rises and stabilizes at a certain level. T 0, and close to the failure critical temperature T 1 room meets T 0< T 1- T s In the formula T s The temperature safety threshold is set at, for example, 20°C, and the temperature fluctuation is within a certain range. T 1- T a , T 1+ T a ), T a During the stable phase, temperature fluctuations are allowed, such as 5°C; during the degradation phase, joint temperature exceeds the allowable fluctuation range. T 1- T a , T 1+ T a ), and for a period of time t Average temperature within 10 minutes (e.g.) T avg The magnitude of the temperature exceeding the stable temperature is T k , T k A degradation threshold, such as 5°C, is used to determine the failure stage; the joint temperature rises to the critical failure temperature. T 1.

[0051] The method for analyzing joint bearing degradation and failure based on vibration signals is as follows: Vibration signals are measured at frequencies higher than 10kHz, and the spectral characteristics and peak fluctuations are analyzed. The vibration-based criteria for judging joint degradation and failure are as follows: Stable phase: The peak value of the vibration signal under periodic motion stabilizes at a certain level. A Near 0, and close to the critical amplitude of failure A 1 room meets A 0< A 1- A s In the formula A s For temperature safety thresholds, such as 20%. A 1. The amplitude fluctuation is within a certain range ( A 0- A a , A 0+ A a )Inside, A a To allow for a 10% fluctuation in the peak amplitude during the stable phase. A 0; The spectral signal characteristics are stable, and the vibration amplitude of each frequency band is stable within the array [ K Near 0, the absolute value of the fluctuation is less than K a , K a To allow for fluctuations in amplitude at various frequencies during the stable phase, such as 5%. A 0; During the degradation stage, the fluctuation range exceeds the allowable range ( A 0- A a , A 0+ A a ), for a period of time t (e.g., the average maximum amplitude over 10 minutes) A avg The magnitude of the amplitude exceeding the stable amplitude is A k , A k A threshold for determining degradation, such as 5%. A 0, or the vibration amplitude of each frequency band compared to [ K 0] The absolute value of the fluctuation is greater than K a During the failure phase, the fluctuation amplitude rises to the critical failure amplitude. A 1.

[0052] In summary, this invention effectively solves the problem in existing technologies where the actual operating conditions of a swivel compressor cannot be accurately simulated, leading to difficulties in the wear analysis and life prediction of the joint bearings. It also proposes a method for judging the degradation and failure of the joint bearings. This system, through a wedge-shaped drive disk and a swivel structure, can effectively simulate the motion characteristics of the joint bearings in a swivel compressor. By combining a loading spring assembly with a force sensor, high-frequency dynamic periodic loads are applied to the joint bearings, simulating the instantaneous load changes experienced by the joint bearings during compressor operation. The system can perform wear tests on the joint bearings at any speed through stepless speed regulation, comprehensively evaluating the bearing performance under different operating conditions. The system integrates temperature and vibration sensors, enabling real-time temperature and vibration monitoring of the joint bearings under high-frequency reciprocating motion, providing important evidence for rapidly assessing the wear state and failure of the joint friction pairs. The application of this invention will help improve the reliability and performance of swivel compressors, reduce maintenance costs caused by bearing failure, and accelerate the research and development of key components for next-generation aerospace high-pressure swivel compressors.

[0053] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A life testing system for the joint bearing of an aerospace high-pressure oscillating compressor, characterized in that, It includes a drive system (A), a core testing system (B), and a loading system (C); The core test system (B) includes a wedge-shaped drive disk (B1), a pendulum disk (B2), a joint bearing assembly (B3), and a connecting rod assembly (B6). The drive system (A) is connected to the wedge-shaped drive disk (B1) and can drive the wedge-shaped drive disk (B1) to rotate. The pendulum disk (B2) is slidably connected to the inclined surface of the wedge-shaped drive disk (B1). The pendulum disk (B2) is connected to an anti-rotation structure to prevent self-rotation. When the drive system (A) drives the wedge-shaped drive disk (B1) to rotate, the wedge-shaped drive disk (B1) drives the pendulum disk (B2) to move through its inclined surface. One end of the joint bearing assembly (B3) is installed at a non-central position of the pendulum disk (B2), and the other end of the joint bearing assembly (B3) is connected to one end of the connecting rod assembly (B6). A temperature sensor (B4) is provided on the joint bearing assembly (B3), and a vibration sensor (B5) is provided on the connecting rod assembly (B6). The loading system (C) includes a fisheye bearing (C1) and a loading spring assembly (C3). The other end of the connecting rod assembly (B6) is connected to one end of the fisheye bearing (C1), and the other end of the fisheye bearing (C1) is connected to one end of the loading spring assembly (C3). The other end of the loading spring assembly (C3) is fixed. A force sensor (C2) is provided at the connection between the fisheye bearing (C1) and the loading spring assembly (C3).

2. The life testing system for the joint bearing of an aerospace high-pressure oscillating compressor according to claim 1, characterized in that, The drive system (A) includes a drive motor (A1), the output shaft of which is connected to the rotation center of the wedge drive disk (B1) and can drive the wedge drive disk (B1) to rotate; the output shaft of the drive motor (A1) is equipped with a torque measuring instrument (A3) for measuring the torque at the power input end of the wedge drive disk (B1) and a speed measuring instrument (A4) for measuring the rotational speed at the power input end of the wedge drive disk (B1).

3. The life testing system for the joint bearing of an aerospace high-pressure oscillating compressor according to claim 2, characterized in that, A speed reducer (A2) is provided between the output shaft of the drive motor (A1) and the wedge-shaped drive disk (B1). The output shaft of the drive motor (A1) is connected to the input end of the speed reducer (A2), and the output end of the speed reducer (A2) is connected to the rotation center of the wedge-shaped drive disk (B1). The torque measuring instrument (A3) and the speed measuring instrument (A4) are located at the output end of the speed reducer (A2).

4. The life testing system for the joint bearing of an aerospace high-pressure oscillating compressor according to claim 1, characterized in that, The spherical bearing assembly (B3) includes: a spherical bearing mounting hole (B301) on the spherical plate (B2); a spherical bearing mounting threaded hole (B302) surrounding the outer periphery of the spherical bearing mounting hole (B301) and on the spherical plate (B2); a spherical bearing ball socket (B303) embedded in the spherical bearing mounting hole (B301) and forming a joint pair with the spherical bearing ball head (B304); the spherical bearing ball head (B304) is a detachable structure and is connected to the connecting rod assembly (B6) via a spherical bearing ball head connecting threaded rod (B3041); and a spherical bearing fixing plate (B305) fixed on the spherical plate (B2) by mounting screws (B307) and the spherical bearing mounting threaded hole (B302) to restrict the spherical bearing ball socket (B303).

5. The life testing system for the joint bearing of an aerospace high-pressure oscillating compressor according to claim 4, characterized in that, The mounting screw (B307) has a mounting hole for mounting the temperature sensor (B4).

6. The life testing system for the joint bearing of an aerospace high-pressure oscillating compressor according to claim 5, characterized in that, An ear pad (B306) is provided between the joint bearing fixing plate (B305) and the mounting screw (B307), and the wire of the temperature sensor (B4) is fixed to the ear of the ear pad (B306).

7. The life testing system for the joint bearing of an aerospace high-pressure oscillating compressor according to claim 4, characterized in that, The connecting rod assembly (B6) includes a connecting rod assembly connector (B604), which is threadedly connected to the ball joint connecting threaded rod (B3041) of the spherical bearing. The connecting rod assembly connector (B604) is provided with a vibration sensor mounting threaded hole (B601) for mounting a vibration sensor (B5); a connecting rod anti-rotation rope threading hole (B602) for limiting the rotation of the connecting rod assembly (B6); and a connecting rod assembly connecting thread (B603) for connecting a fisheye bearing (C1). The fisheye bearing (C1) includes a fisheye bearing assembly (C102). One end of the fisheye bearing assembly (C102) is connected to the connecting rod assembly connecting thread (B603) via a connecting threaded sleeve (C101). The other end of the fisheye bearing assembly (C102) is connected to the loading system (C) via a fisheye bearing connecting thread (C103). The force sensor (C2) is disposed between the fisheye bearing connecting thread (C103) and the loading system (C).

8. The life testing system for the joint bearing of an aerospace high-pressure oscillating compressor according to claim 1, characterized in that, The stiffness and pre-compression of the loading spring assembly (C3) are adjustable. The unidirectional stroke of the reciprocating motion of the loading spring assembly (C3) is... s At that time, by adjusting the spring stiffness K I and pre-compression amount Δ L I The combined piston force of each stage of the actual compressor F NI Time satisfies F I-min = K I Δ L I = F NI-min , F I-max = K I (Δ) L I +s )= F NI-max This is to simulate the periodic changes in piston force in an actual compressor.

9. A method for testing the life of a spherical bearing in an aerospace high-pressure oscillating compressor, characterized in that, This method uses the test system described in any one of claims 1-8 and includes the following steps: The speed control is consistent with that of the actual compressor by adjusting the drive system (A). The drive system (A) drives the wedge drive disk (B1) to rotate, and the wedge drive disk (B1) drives the swing disk (B2) to swing. During the swing of the swing disk (B2), the joint bearing assembly (B3) moves with the swing disk (B2) and can drive the loading spring assembly (C3) to reciprocate through the connecting rod assembly (B6) and the fisheye bearing (C1). The loading spring assembly (C3) simulates dynamic periodic load and collects the detection data of the force sensor (C2), temperature sensor (B4) and vibration sensor (B5) in real time. The degradation and failure of the joint bearing assembly (B3) were analyzed using the detection data from the force sensor (C2), temperature sensor (B4), and vibration sensor (B5).

10. The method for testing the life of a spherical bearing in an aerospace high-pressure oscillating compressor according to claim 9, characterized in that, The data acquisition frequency of the vibration sensor (B5) is ≥10kHz. The spectral characteristics and peak fluctuations are obtained based on the detection data of the vibration sensor (B5). The logic for judging the degradation and failure of the spherical bearing assembly (B3) by analyzing the detection data of the force sensor (C2), temperature sensor (B4), and vibration sensor (B5) includes: Stable phase: Temperature fluctuation range is within T 0± T a Within the range, and T 0< T 1 T s The peak vibration fluctuation range is within A 0± A a Within the range and the spectral amplitude fluctuation is less than K a ;in, T 0 represents the average detection value of the temperature sensor (B4). T a To allow for temperature fluctuations during the stable phase T 1 represents the critical failure temperature. T s For temperature safety threshold, A 0 represents the stable mean value of the vibration peak value. A a To allow for amplitude fluctuations during the stable phase of the vibration peak. K a This is the allowable fluctuation range of amplitude at each frequency during the stable phase. Degradation stage: Temperature continues to exceed T 0+ T k Or the peak vibration level continues to exceed A 0+ A k or the spectral amplitude fluctuation exceeds K a ;in, T k The threshold for determining degradation A k The threshold for determining degradation; Failure stage: Temperature reaches the critical failure value T 1 or the vibration peak value reaches the failure threshold. A 1.

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