Spline full-period fatigue test system capable of rapidly replacing piece to be tested

Abstract

A spline full-cycle fatigue test system capable of quickly replacing a to-be-tested piece relates to the field of predictive maintenance and fault testing, and comprises a vibration isolation base and two supporting and positioning units, each supporting and positioning unit comprises a bearing supporting seat and a shaft sleeve, the two bearing supporting seats of the two supporting and positioning units are fixed to the vibration isolation base and are oppositely arranged at intervals. The shaft sleeve is provided with a flange connecting disc, connected with the bearing supporting seat and used for transmitting torque. The flange connecting discs of the two shaft sleeves can be detachably connected with a to-be-tested external spline and a to-be-tested internal spline respectively. The test piece can be quickly disassembled and assembled, the operation is simple, and the efficiency is high; the device can adapt to tests of test pieces of different models, and is wide in application range.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of predictive maintenance and fault testing, and in particular to a spline full-cycle fatigue test system capable of quickly replacing a test piece. BACKGROUND As a key component for realizing the circumferential fixation of shafts and shaft parts and transmitting torque in mechanical transmission systems, splines are widely used in the fields of automobiles, aerospace, engineering machinery, etc. They are subjected to alternating loads during operation and are prone to failure modes such as tooth surface wear and tooth root fatigue fracture. Therefore, testing the full-cycle fatigue performance of splines to obtain their failure mechanisms and life characteristics under different working conditions is an important link to ensure the reliability of mechanical systems. Traditional spline fatigue test benches usually use fixed connection structures, and the test spline and transmission shaft system are usually rigidly fixed through key connection, interference fit or flange bolt set. When different specifications of spline test pieces need to be replaced (such as inner and outer spline pairing, contact tooth width adjustment, etc.), special tools are needed to disassemble the entire transmission chain, which is time-consuming and labor-intensive and prone to cumulative installation errors. For example, when adjusting the contact tooth width of the inner and outer splines, the existing equipment needs to re-machine the shaft system components or rely on manual field matching, which makes it difficult to meet the testing needs of quick switching of multiple types of test pieces. The spline fatigue failure process is accompanied by changes in multiple physical field signals such as vibration noise, torque fluctuation, material micro-damage acoustic emission, etc. However, traditional test benches are generally equipped with only a single torque or speed sensor, which cannot synchronously capture multi-dimensional failure characteristics. Although some equipment integrates vibration sensors, the sensors are usually installed using adhesive or temporary clamping methods, which are susceptible to contact impedance and environmental noise interference, and cannot achieve symmetric acquisition of input and output multi-directional vibration signals, resulting in insufficient precision in identifying early-stage fatigue failure characteristics. In spline fatigue testing, it is crucial to accurately simulate the speed fluctuation, torque load, and installation errors such as shaft system misalignment and eccentricity under actual working conditions. Existing working condition control modules mostly use open-loop control, with low resolution in speed and torque adjustment, making it difficult to achieve dynamic load spectrum loading. The eccentricity error implantation relies on manual experience adjustment and lacks quantitative adjustment methods based on geometric relationships, resulting in uncontrollable error implantation precision and affecting the repeatability of test results.

[0002] To address the above industry-wide problems, there is an urgent need to invent a spline full-cycle fatigue test bench with the functions of quick replacement of test pieces, synchronous acquisition of multi-source signals, and precise working condition simulation, to break through the technical barriers of traditional test platforms in terms of testing efficiency, data accuracy, and working condition adaptability, provide an efficient and reliable engineering test platform for spline fatigue performance research, and promote the progress of mechanical transmission system reliability technology. SUMMARY

[0003] The purposes of the present application include, for example, providing a spline full-cycle fatigue test system capable of quickly replacing a test piece, achieving quick disassembly and assembly of the test piece, being simple and efficient to operate, and being suitable for testing different types of test pieces and having a wide range of applications.

[0004] Embodiments of the present application can be implemented as follows: In a first aspect, the present application provides a spline full-cycle fatigue test system capable of quickly replacing a test piece, which is used in cooperation with a test outer spline and a test inner spline capable of being engaged by insertion, the test outer spline is provided with a first mounting flange, the test inner spline is provided with a second mounting flange, and the system comprises: a vibration isolation base and two support positioning units, each of the support positioning units comprises a bearing support seat and a shaft sleeve, the two bearing support seats of the two support positioning units are fixed to the vibration isolation base and arranged in opposite directions; the shaft sleeve is provided with a flange connecting disc, and the shaft sleeve is connected with the bearing support seat for torque transmission; the two flange connecting discs of the two support positioning units are detachably connected with the first mounting flange and the second mounting flange, respectively.

[0005] In an optional embodiment, the bearing support seat comprises a support seat body, a support bearing, and a mounting shaft, the support seat body is connected with the vibration isolation base, the outer ring of the support bearing is mounted to the support seat body, the mounting shaft is mounted to the inner ring of the support bearing, the shaft sleeve is connected with the mounting shaft, and the two are fixed in opposite directions in the circumferential direction of the mounting shaft.

[0006] In an optional embodiment, the shaft sleeve and the mounting shaft are slidably connected in the axial direction of the mounting shaft.

[0007] In an optional embodiment, the shaft sleeve is provided with a positioning plane for contacting the test outer spline or the test inner spline, the positioning plane is provided with a first concave-convex structure, and the first concave-convex structure is used for insertion cooperation with a second concave-convex structure on the test outer spline or the test inner spline.

[0008] In an optional embodiment, the first concave-convex structure is arranged as a positioning circular table coaxial with the shaft sleeve.

[0009] In an optional embodiment, the spline full-cycle fatigue test system further comprises a driving motor, a first coupling, an eddy current brake, a second coupling, and an output shaft, the driving motor and the eddy current brake are both mounted to the vibration isolation base, the first coupling is connected to the driving motor and one of the two shaft sleeves at the same time; the second coupling is connected to the output shaft and the other of the two shaft sleeves at the same time, and the output shaft cooperates with the eddy current brake.

[0010] In an optional embodiment, the spline full-cycle fatigue test system further comprises a torque speed acquisition instrument, a torque speed display instrument and a torque speed sensor, the torque speed sensor is installed on the vibration isolation base and used to acquire torque and speed of the output shaft, the torque speed sensor is electrically connected with the torque speed acquisition instrument, and the torque speed acquisition instrument is electrically connected with the torque speed display instrument.

[0011] In an optional embodiment, the spline full-cycle fatigue test system further comprises an acoustic emission signal acquisition instrument and an acoustic emission sensor, the acoustic emission sensor is installed on the outer side surface of the bearing support base, and the acoustic emission sensor is electrically connected with the acoustic emission signal acquisition instrument.

[0012] In an optional embodiment, the spline full-cycle fatigue test system further comprises a dynamic signal acquisition instrument and a three-way acceleration sensor, the three-way acceleration sensor is installed on the end surface of the bearing support base, the Z axis of the three-way acceleration sensor is parallel to the axis of the shaft sleeve, and the three-way acceleration sensor is electrically connected with the dynamic signal acquisition instrument.

[0013] In an optional embodiment, the three-way acceleration sensor is fixed on the end surface of the bearing support base by magnetic attraction.

[0014] The beneficial effects of the embodiments of the present application include, for example: In summary, the spline full-cycle fatigue test system provided by the present embodiment comprises two support positioning units arranged on the vibration isolation base, each support positioning unit comprises a bearing support base and a shaft sleeve, the shaft sleeve is installed on the bearing support base and can rotate relative to the bearing support base. Meanwhile, the shaft sleeve is provided with a flange connection disc, and the flange connection discs of the two shaft sleeves can be detachably connected with the measured external spline and the measured internal spline, respectively. In this way, when the measured external spline and the measured internal spline need to be replaced, only the bolts connecting the shaft sleeve with the measured external spline or the measured internal spline need to be removed, and then the measured internal spline and the measured external spline can be taken out along the radial direction of the shaft sleeve, without the need to axially move the driver, the loader and other structures, so that the replacement is convenient and fast, time-saving and labor-saving, and efficient. Meanwhile, when installing a new measured part, the measured part is placed between the two shaft sleeves, and then the measured part is fastened between the two shaft sleeves by using bolts, so that the installation is convenient and fast. After the installation is completed, the torque is transmitted to the measured internal spline and the measured external spline by the driver, and then the load can be set at the output end, so as to record various parameters of the measured internal spline and the measured external spline during work, and the spline full-cycle fatigue test result is accurate and has high guiding significance. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation to the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0016] Figure 1 Figure is a schematic diagram of the spline full-cycle fatigue test system of the present embodiment; Figure 2 Figure is a partial schematic diagram of the spline full-cycle fatigue test system of the present embodiment; Figure 3 Figure is a schematic diagram of the spline assembly to be tested of the present embodiment; Figure 4 Figure is a first control flowchart of the present embodiment; Figure 5 Figure is a second control flowchart of the present embodiment; Figure 6 Figure is a third control flowchart of the present embodiment.

[0017] Figure legend: 01-spline assembly to be tested; 001-outer spline to be tested; 011-first mounting flange; 012-first shaft section; 013-second shaft section; 014-outer spline tooth; 015-first through hole; 016-first positioning groove; 002-inner spline to be tested; 021-second mounting flange; 022-third shaft section; 023-inner spline tooth; 024-second through hole; 025-second positioning groove; 003-control module; 004-computer; 100-vibration isolation base; 200-support positioning unit; 210-bearing support seat; 211-support seat body; 212-support bearing; 213-mounting shaft; 220-shaft sleeve; 221-flange connecting disc; 300-driving motor; 400-first coupling; 500-electric eddy current brake; 600-output shaft; 700-torque and speed acquisition instrument; 800-torque and speed display instrument; 810-torque and speed sensor; 900-acoustic emission signal acquisition instrument; 910-acoustic emission sensor; 920-dynamic signal acquisition instrument; 930-three-way acceleration sensor. DETAILED DESCRIPTION

[0018] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will combine the drawings in the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the application. Based upon these embodiments of the application, those skilled in the art who have the benefit of this application will appreciate all other embodiments that are taught by the application without departing from the scope of the application.

[0020] It should be noted that similar reference numbers and letters refer to similar items in the following drawings, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0021] In the description of the application, it should be noted that if the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed, and are only for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0022] In addition, if the terms "first", "second" and the like appear, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0023] It should be noted that the features in the embodiments of the application can be combined with each other without conflict.

[0024] Embodiment 1 Please refer to Figures 1-6 The embodiment provides a spline full-cycle fatigue test system capable of quickly replacing a to-be-tested part, which comprises: A vibration isolation base 100 and two support positioning units 200, each support positioning unit 200 comprises a bearing support seat 210 and a shaft sleeve 220, the two bearing support seats 210 of the two support positioning units 200 are fixed to the vibration isolation base 100 and arranged at a relative interval; the shaft sleeve 220 is provided with a flange connecting disc 221, the shaft sleeve 220 is connected with the bearing support seat 210 and is used for transmitting torque. The flange connecting discs 221 of the two shaft sleeves 220 can be detachably connected with a to-be-tested outer spline 001 and a to-be-tested inner spline 002 respectively.

[0025] It should be noted that in the embodiment, the test object of the test system, i.e., the structure of the to-be-tested outer spline 001 and the to-be-tested inner spline 002 cooperating with each other, is as follows: Please refer to Figure 3The measured external spline 001 comprises an integral first mounting flange 011, a first shaft section 012 and a second shaft section 013. The first mounting flange 011 is located at one end of the first shaft section 012, and the second shaft section 013 is located at the other end of the first shaft section 012. The first mounting flange 011, the first shaft section 012 and the second shaft section 013 are coaxially arranged. The outer diameter of the first mounting flange 011, the outer diameter of the first shaft section 012 and the outer diameter of the second shaft section 013 decrease in turn, that is, the measured external spline 001 is arranged as a three-step shaft. The outer peripheral surface of the second shaft section 013 is provided with external spline teeth 014. The end of the external spline teeth 014 close to the first shaft section 012 has a spacing with the first shaft section 012, that is, part of the outer peripheral surface of the second shaft section 013 is not occupied by the external spline teeth 014, but is a smooth section. Meanwhile, the measured external spline 001 is internally provided with a first through hole 015. The first through hole 015 simultaneously penetrates the first mounting flange 011, the first shaft section 012 and the second shaft section 013. The first through hole 015 is a circular hole and coaxial with the first mounting flange 011. The end face of the first mounting flange 011 away from the first shaft section 012 is provided with a first positioning groove 016. The first positioning groove 016 surrounds and communicates with the first through hole 015. The first positioning groove 016 can be a circular groove or a circular truncated cone groove, etc.

[0026] The measured internal spline 002 comprises an integral second mounting flange 021 and a third shaft section 022. The second mounting flange 021 is located at one end of the third shaft section 022, and the second mounting flange 021 and the third shaft section 022 are coaxially arranged. The outer diameter of the second mounting flange 021 is greater than the outer diameter of the third shaft section 022, that is, the measured external spline 001 is arranged as a two-step shaft. Meanwhile, the measured external spline 001 is internally provided with a second through hole 024. The second through hole 024 simultaneously penetrates the second mounting flange 021 and the third shaft section 022. The second through hole 024 is a circular hole and coaxial with the second mounting flange 021. The end face of the second mounting flange 021 away from the third shaft section 022 is provided with a second positioning groove 025. The second positioning groove 025 surrounds and communicates with the second through hole 024. The second positioning groove 025 can be a circular groove or a circular truncated cone groove, etc. The inner spline teeth 023 are arranged on the hole wall of the second through hole 024.

[0027] Before testing, the to-be-tested external spline 001 is inserted into the to-be-tested internal spline 002, after the insertion, the second shaft section 013 of the to-be-tested external spline 001 can be completely inserted into the second through hole 024, at this time, the length of the structure formed by the to-be-tested external spline 001 and the to-be-tested internal spline 002 is the shortest, the volume is small, when the to-be-tested external spline 001 and the to-be-tested internal spline 002 are placed between the two shaft sleeves 220, it is not easy to collide and interfere with the two shaft sleeves 220, and the installation is convenient and fast. Then, the to-be-tested external spline 001 and the to-be-tested internal spline 002 are moved away from each other, the first mounting flange 011 of the to-be-tested external spline 001 is fixedly connected with the flange connecting disc 221 of one shaft sleeve 220 through a bolt, and the second mounting flange 021 of the to-be-tested internal spline 002 is fixedly connected with the flange connecting disc 221 of the other shaft sleeve 220 through a bolt, at this time, the external spline teeth 014 are also engaged with the internal spline teeth 023, and torque transmission can be achieved. At the same time, since the to-be-tested external spline 001 is provided as a three-step shaft, when the to-be-tested external spline 001 is inserted into the second through hole 024, the smooth section of the second shaft section 013 has a spacing with the hole wall of the second through hole 024 and the internal spline teeth 023, and it is not easy to contact and rub, the wear is small, and the sliding is convenient.

[0028] It should be understood that, since the shaft sleeve 220 is detachably connected with the to-be-tested external spline 001 or the to-be-tested internal spline 002 through the flange structure, when the spline test assembly 01 formed by the to-be-tested external spline 001 and the to-be-tested internal spline 002 that are engaged with each other is replaced, the bolt is removed, and the spline test assembly 01 can be directly taken out along the radial direction of the shaft sleeve 220, without the need to move other components in the axial direction, and the operation is convenient. Similarly, when assembling, the spline test assembly 01 is placed between the two shaft sleeves 220, and then fixed by using a bolt, and the installation is convenient.

[0029] At the same time, since the support and positioning unit 200 is installed on the vibration isolation base 100, during the test process, the vibration can be reduced, and the interference on the test result is reduced.

[0030] The details of the spline full-cycle fatigue test system of the embodiment of the present application are described below in an exemplary manner.

[0031] Please refer to Figures 1-6 Optionally, a plurality of mounting grooves can be arranged on the vibration isolation base 100, and the bearing support seat 210 can be fixed in the mounting grooves through a bolt or other structural member. Through the design of the mounting grooves, the coaxiality of the two shaft sleeves 220 can be improved, and when the distance between the two shaft sleeves 220 is adjusted, the bearing support seat 210 slides along the length direction of the mounting grooves, the sliding is convenient, and the two shaft sleeves 220 always maintain coaxiality during the sliding process, and are not easy to be misaligned, and the tedious steps of repeated positioning are saved. It should be understood that the mounting grooves can be T-shaped grooves or dovetail grooves, and in addition, the number of the mounting grooves can be designed as required.

[0032] Optionally, the bearing support seat 210 comprises a support seat body 211, a support bearing 212 and a mounting shaft 213. The support seat body 211 can be fixed on the vibration isolation base 100 by bolts, the support seat body 211 is internally provided with a mounting through hole, the outer ring of the support bearing 212 is embedded in the mounting through hole and is fixedly connected with the support seat body 211, and the mounting shaft 213 is provided through the inner ring of the support bearing 212 and is fixedly connected with the inner ring. The shaft sleeve 220 is sleeved outside the mounting shaft 213, and the shaft sleeve 220 is relatively fixed with the mounting shaft 213 in the circumferential direction of the mounting shaft 213, that is, the shaft sleeve 220 cannot rotate relative to the mounting shaft 213, and the two rotate together to transmit torque.

[0033] Further, the shaft sleeve 220 can also be slidably matched with the mounting shaft 213 in the axial direction of the mounting shaft 213, so as to adjust the distance between the two shaft sleeves 220, and further adjust the meshing length of the to-be-tested external spline 001 and the to-be-tested internal spline 002. That is, according to the test requirements, the distance between the two shaft sleeves 220 can be adjusted first, and after the position adjustment of the two shaft sleeves 220 is completed, the shaft sleeve 220 is axially fixed relative to the mounting shaft 213. Then, the to-be-tested external spline 001 and the to-be-tested internal spline 002 are placed between the two shaft sleeves 220, and the to-be-tested external spline 001 and the to-be-tested internal spline 002 are axially slid as needed. The meshing length of the external spline teeth 014 and the internal spline teeth 023 is adaptively adjusted according to the distance between the shaft sleeves 220, so as to realize the test of different meshing lengths of the spline to-be-tested assembly 01, which is flexible and has a wide test range. This design avoids the complicated process of on-site matching or replacing shaft parts of the traditional test bench, and only needs to preset the meshing length according to the test requirements before the test, so as to realize the rapid switching test of assemblies with different meshing lengths.

[0034] For example, in the embodiment, the mounting shaft 213 can be provided as a flat key shaft, and the hole wall of the shaft sleeve 220 is provided with a flat key groove. The mounting shaft 213 is inserted into the shaft sleeve 220 and is clamped with the flat key hole. In this way, the shaft sleeve 220 is connected with the mounting shaft 213, and the two are relatively fixed in the circumferential direction of the mounting shaft 213 and can slide in the axial direction of the mounting shaft 213. It should be understood that the shaft sleeve 220 and the mounting shaft 213 can be in interference fit by means of hot fitting, that is, by heating the shaft sleeve 220, the inner hole of the shaft sleeve 220 can be expanded. At this time, the installation and sliding of the mounting shaft 213 can be facilitated. When the position adjustment of the mounting shaft 213 and the shaft sleeve 220 is completed, the inner hole of the shaft sleeve 220 is gradually contracted by cooling, so as to realize the interference fit with the mounting shaft 213.

[0035] Optionally, the shaft sleeve 220 is provided with a positioning plane capable of being attached to the first mounting flange 011 or the second mounting flange 021, and the positioning plane is provided with a protrusion, the shape of the protrusion matches the shape of the first positioning groove 016 or the second positioning groove 025, for example, the protrusion can be a ring-shaped positioning circular platform, when the shaft sleeve 220 is matched with the measured external spline 001 or the measured internal spline 002, the positioning circular platform on the positioning plane can be inserted into the first positioning groove 016 or the second positioning groove 025, thereby realizing accurate axial centering and improving coaxiality. It should be understood that the protrusion on the positioning plane can also be referred to as a first concave-convex structure, and the first positioning groove 016 or the second positioning groove 025 can be referred to as a second concave-convex structure, and the first concave-convex structure and the second concave-convex structure can also be provided as other clamping and matching structures.

[0036] It should be understood that the shaft sleeve 220 can be processed by using 45 structural steel, and the measured internal spline 002 or the measured external spline 001 is processed by using Q235 steel, so as to ensure that the spline test assembly 01 has a strength far lower than other components during spline running test, and to reduce the interference of other fault signals as much as possible. Eight evenly distributed through holes can be arranged on the flange connecting disc 221, and correspondingly, the first mounting flange 011 and the second mounting flange 021 can be uniformly arranged with eight through holes.

[0037] Please refer to Figures 1-6 In the embodiment, optionally, the spline full-cycle fatigue test system further includes a driving motor 300, a first coupling 400, an eddy current brake 500, a second coupling (not shown in the figure), an output shaft 600, a torque and speed acquisition instrument 700, a torque and speed display instrument 800, a torque and speed sensor 810, an acoustic emission signal acquisition instrument 900, an acoustic emission sensor 910, a dynamic signal acquisition instrument 920, and a three-way acceleration sensor 930. The driving motor 300 can be electrically connected to the input end speed condition control module 003 through a cable. The acoustic emission signal acquisition instrument 900 can be electrically connected to the computer 004 through a cable.

[0038] The driving motor 300 and the eddy current brake 500 are both mounted on the vibration isolation base 100, the first coupling 400 is connected to the driving motor 300 and one of the two shaft sleeves 220, the second coupling is connected to the output shaft 600 and the other of the two shaft sleeves 220, and the eddy current brake 500 cooperates with the output shaft 600. After the driving motor 300 is started, the torque can be transmitted to the spline to-be-tested assembly 01 through the first coupling 400, then the torque is transmitted to the second coupling through the spline to-be-tested assembly 01, the second coupling transmits the torque to the output shaft 600, and the torque output is realized through the output shaft 600. The eddy current brake 500 can provide load for the output shaft 600 to simulate the loading test. The torque speed sensor 810 is mounted on the vibration isolation base 100 and corresponds to the position of the output shaft 600, and is used to obtain the torque and speed of the output shaft 600. The torque speed sensor 810 is electrically connected to the torque speed collector 700 through a cable, and the torque speed collector 700 is electrically connected to the torque speed display instrument 800 through a cable. The number of acoustic emission sensors 910 is four, two acoustic emission sensors 910 form a group, two groups of acoustic emission sensors 910 correspond to two support base bodies 211 respectively, and the two acoustic emission sensors 910 in the same group are both mounted on the outer side surface of the support base body 211. All the acoustic emission sensors 910 are electrically connected to the acoustic emission signal collector 900 through cables. Two acoustic emission sensors 910 are arranged on each support base body 211, and through the redundant design, the accuracy of the sound collection signal can be improved, and in the case that one of them is damaged, the other can continue to work, ensuring the continuity of the test. The number of three-way acceleration sensors 930 is two, and the two three-way acceleration sensors 930 are respectively mounted on the end surfaces of the two support base bodies 211. The Z axes of the two three-way acceleration sensors 930 are parallel to the axial direction of the shaft sleeve 220, so that data conversion is not needed, and the parameters are easy to record. At the same time, the two three-way acceleration sensors 930 are electrically connected to the dynamic signal collector 920 through cables.

[0039] Optionally, the three-way acceleration sensor 930 can be fixed on the end surface of the support base body 211 by magnetic attraction, which is convenient and reliable to install.

[0040] Optionally, the first coupling 400 and the second coupling can both be toothed couplings. In addition, the output shaft 600 and the mounting shaft 213 can be directly connected, and the second coupling is omitted.

[0041] The spline full-cycle fatigue test system provided by the embodiment forms a technical solution covering the whole process of spline testing through the rigid support of the vibration isolation bottom plate, the quick disassembly and assembly structure of the modular test piece, the closed-loop control working condition simulation system, and the collaborative work of the multi-source signal synchronous acquisition network, effectively solves the problems of time-consuming replacement of traditional test benches, working condition simulation distortion, and incomplete signal monitoring, and provides a reliable test platform for spline full-cycle fatigue performance research.

[0042] The spline full-cycle fatigue test system provided by the embodiment has the following advantages: 1. Rapid replacement of test piece and breakthrough in test efficiency The test system adopts a modular design concept, connects the spline test component 01 and the transmission system through a standardized interface: the shaft sleeve 220 and the bearing support seat 210 form a rigid transmission base through interference fit, and the shaft sleeve 220 and the spline test component 01 are connected through evenly distributed bolts. This design breaks the limitation of traditional test benches that need to disassemble the entire transmission chain. When replacing the test piece, the spline part can be disassembled independently by loosening the bolts, without the need for special tools or complex procedures, greatly shortening the test piece replacement time. Combined with the stepped shaft structure design of the outer spline 001 and the inner spline 002 to be tested, the spline test component 01 can be pre-set to the meshing length by moving axially before testing, avoiding the cumbersome operation of on-site grinding or replacing shaft parts in traditional schemes. This design supports quick switching of spline test pieces with different tooth width, modulus, and number of teeth, significantly improving the test bench's adaptability to multiple product types, especially suitable for high-frequency and multi-specification research and testing needs in the automotive, aerospace, and other fields, fundamentally solving the pain point of time-consuming replacement of traditional equipment.

[0043] 2. Multi-dimensional signal monitoring and full-cycle capture of failure characteristics A multi-physical field monitoring system covering vibration, acoustic emission, and load transmission is constructed by symmetrically arranging various sensors at the input and output ends: the three-axis acceleration sensor 930 is rigidly installed by magnetic attraction, which can capture the vibration response of the spline in three orthogonal directions in real time, avoiding signal attenuation and noise interference caused by gluing or temporary clamping, and ensuring that the vibration signal fully reflects the running state of the spline; the acoustic emission sensor 910 is closely attached to the bearing support seat 210 through a coupling agent, which can sensitively capture the stress wave signals generated during the initiation and propagation of micro-cracks on the tooth surface, and accurately capture the early features of fatigue failure; the torque and speed sensor 810 corresponds to the output shaft 600 and is integrated at the key node of the transmission chain, which can directly obtain the dynamic parameters in the load transmission process and eliminate the influence of the connection gap on the measurement accuracy. The multi-source signals are synchronously transmitted to the acquisition system through low-noise cables, and the full-cycle failure features of the spline from initial wear to macroscopic fracture can be fully presented after fusion analysis, which provides multi-dimensional data support for in-depth study of the failure mechanism and solves the one-sidedness problem of traditional single-parameter monitoring.

[0044] 3. Work condition simulation accuracy and error implantation ability improvement The input end speed control module 003 composed of the driving motor 300 and the first coupling 400 cooperates with the output end torque loading module composed of the eddy current brake 500, the second coupling, and the output shaft 600 through closed-loop control logic, which can dynamically adjust the speed and torque load according to the actual working condition requirements, and support the precise loading of complex load spectrum such as sine wave and square wave. For shafting installation error simulation, the misalignment of the coupling is measured by the double gauge method, the radial and angular deviations are accurately calculated through geometric relationship, and the error is quantitatively implanted by adding or removing shims on the motor base. This method changes the traditional extensive mode relying on manual experience adjustment, realizes the precise control of shafting eccentric error, can reproduce the actual working conditions such as speed fluctuation during gear shifting of automobile transmission and torque impact during start and stop of aviation transmission system, makes the test environment highly consistent with the engineering application scene, and ensures that the fatigue test results can directly guide the actual product design, thereby improving the engineering application value of test data.

[0045] Among them, shims are arranged below the driving motor 300 at the input end and the bearing 212 seat, and the eccentric error of the measured part is implanted by the double gauge method, as follows: According to the test system parameters and the size parameters of the tooth coupling, the misalignment of the coupling is measured by the double gauge method, and the relationship between the misalignment and the measured value is derived according to the geometric relationship; according to the misalignment measurement method, the eccentricity of the measured part is adjusted by adding or removing shims on the front and rear feet of the base of the variable speed driving motor 300.

[0046] 4. Low-interference test environment and high-reliability design By material strength gradient design, the shaft sleeve 220 is deliberately selected to have higher strength than the spline, so that the spline becomes the only weak link in the transmission chain, ensuring that other components (such as bearings and couplings) will not fail before the spline during testing, avoiding unrelated failure signals interfering with test results. The shaft slot positioning system of the vibration isolation base plate is rigidly connected to the T-shaped anchor bolt structure, effectively suppressing the transmission of external vibrations and mechanical noise. Combined with the magnetic and coupled rigid installation method of the sensor, the influence of environmental noise on signal acquisition is further reduced. This design creates a high-purity test environment, allowing the collected signals to accurately reflect the fatigue state of the spline, improving the reliability of failure analysis and providing a strong guarantee for accurately determining the fatigue life of the spline.

[0047] 5. Standardized architecture and device scalability enhancement The equally spaced shaft slots and positioning holes on the vibration isolation base plate form a standardized installation reference, supporting flexible layout and accurate positioning of components such as power modules, bearing support seats 210, brakes, and sensors. The cooperation design of anchor bolts and shaft slots allows each module to adjust its position within a certain range, eliminating the need for reprocessing the base plate to adapt to the testing needs of spline test pieces of different sizes, significantly improving the versatility of the device. This scalable design not only reduces the hardware modification cost of multiple model testing, but also allows the test bench to quickly reconfigure the transmission chain shaft distance according to actual needs, adapt to testing scenarios with different axial lengths of internal and external splines, meet future possible technical upgrades and function extensions, and demonstrate strong engineering practicality and foresight.

[0048] The above beneficial effects are achieved through the synergistic innovation of each technical module, making the present application have both technical advancement and engineering practicality in the spline fatigue testing field, effectively promoting the progress of related testing technology and providing important technical support for the reliability research of mechanical transmission components.

[0049] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present application can be easily thought of by those skilled in the art, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A spline full-cycle fatigue test system capable of quickly replacing a test piece, used in cooperation with a test outer spline (001) and a test inner spline (002) capable of being engaged by plugging, the test outer spline (001) is provided with a first mounting flange (011), and the test inner spline (002) is provided with a second mounting flange (021), characterized in that, The vibration isolation base (100) and two support positioning units (200), each of the support positioning units (200) comprises a bearing support seat (210) and a shaft sleeve (220), the two bearing support seats (210) of the two support positioning units (200) are fixed to the vibration isolation base (100) and are arranged at a relative interval; the shaft sleeve (220) is provided with a flange connecting disc (221), the shaft sleeve (220) is connected with the bearing support seat (210), and torque is transmitted; The two flange connecting discs (221) of the two support positioning units (200) are detachably connected with the first mounting flange (011) and the second mounting flange (021) respectively.

2. The spline full-cycle fatigue test system according to claim 1, wherein: The bearing support seat (210) comprises a support seat body (211), a support bearing (212) and a mounting shaft (213), the support seat body (211) is connected with the vibration isolation base (100), the outer ring of the support bearing (212) is mounted on the support seat body (211), the mounting shaft (213) is mounted on the inner ring of the support bearing (212), the shaft sleeve (220) is connected with the mounting shaft (213), and the two are fixed relative to each other in the circumferential direction of the mounting shaft (213).

3. The spline full-cycle fatigue test system according to claim 2, wherein: The shaft sleeve (220) and the mounting shaft (213) are slidably connected in the axial direction of the mounting shaft (213).

4. The spline full-cycle fatigue test system according to claim 1, wherein: The shaft sleeve (220) is provided with a positioning plane for contacting the measured external spline (001) or the measured internal spline (002), the positioning plane is provided with a first concave-convex structure, and the first concave-convex structure is used for plug-in cooperation with a second concave-convex structure on the measured external spline (001) or the measured internal spline (002).

5. The spline full-cycle fatigue test system according to claim 4, wherein: The first concave-convex structure is arranged as a positioning circular table coaxial with the shaft sleeve (220).

6. The spline full-cycle fatigue test system according to any one of claims 1-5, wherein: The spline full-cycle fatigue test system further comprises a driving motor (300), a first coupling (400), an eddy current brake (500), a second coupling and an output shaft (600), the driving motor (300) and the eddy current brake (500) are mounted on the vibration isolation base (100), the first coupling (400) is connected to the driving motor (300) and one of the two shaft sleeves (220) at the same time; the second coupling is connected to the output shaft (600) and the other of the two shaft sleeves (220) at the same time, and the output shaft (600) cooperates with the eddy current brake (500). ​ 7. The spline full-cycle fatigue test system according to claim 6, characterized in that: The spline full-cycle fatigue test system further comprises a torque and speed acquisition instrument (700), a torque and speed display instrument (800) and a torque and speed sensor (810), the torque and speed sensor (810) is installed on the vibration isolation base (100) and used to acquire the torque and speed of the output shaft (600); the torque and speed sensor (810) is electrically connected with the torque and speed acquisition instrument (700), and the torque and speed acquisition instrument (700) is electrically connected with the torque and speed display instrument (800).

8. The spline full-cycle fatigue test system according to claim 1, characterized in that: The spline full-cycle fatigue test system further comprises an acoustic emission signal acquisition instrument (900) and an acoustic emission sensor (910), the acoustic emission sensor (910) is installed on the outer side surface of the bearing support base (210), and the acoustic emission sensor (910) is electrically connected with the acoustic emission signal acquisition instrument (900).

9. The spline full-cycle fatigue test system according to claim 1, characterized in that: The spline full-cycle fatigue test system further comprises a dynamic signal acquisition instrument (920) and a three-way acceleration sensor (930), the three-way acceleration sensor (930) is installed on the end surface of the bearing support base (210), the Z-axis of the three-way acceleration sensor (930) is parallel to the axis of the shaft sleeve (220), and the three-way acceleration sensor (930) is electrically connected with the dynamic signal acquisition instrument (920).

10. The spline full-cycle fatigue test system according to claim 9, characterized in that: The three-way acceleration sensor (930) is fixed on the end surface of the bearing support base (210) by magnetic attraction.

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