Fatigue test assembly for spring and integrated fatigue test machine

Abstract

The invention discloses a fatigue test assembly for a spring and an integrated fatigue test machine. The invention relates to the technical field of spring production equipment. Comprising a rack 4 and a bearing assembly 3 arranged in the rack 4 and used for bearing a tested spring. The linear driving part 2 is used for driving the bearing assembly 3 to linearly move along the axial direction of the tested spring; and the adjusting unit 5 is used for driving the bearing assembly 3 to axially rotate along the tested spring. When in use, the tested spring is placed on the bearing assembly 3, and based on the set linear position of the tested spring (namely, the test is executed aiming at the stretchability) and the rotation stroke (namely, the test is executed aiming at the stress property); according to the invention, two stress testing functions of stretching and rotating are integrated, and the fatigue performance and reliability of the spring under the combined stress condition can be comprehensively evaluated. By simulating tensile and torsional stress possibly encountered in actual use, the performance of the spring in actual application can be predicted more accurately.

Description

Technical Field

[0001] The present invention relates to the technical field of spring production equipment, in particular to equipment for performing fatigue testing and verification on springs, and in particular to a fatigue testing assembly for springs and an integrated fatigue testing machine. Background Art

[0002] Spring fatigue testing occupies an important position in the field of materials science and engineering. It is directly related to the durability and safety of the product and the ability of the material to resist fatigue damage under cyclic stress. In actual use, the spring will be repeatedly subjected to alternating stress, which will gradually cause cracks and damage inside the material, and eventually cause fatigue fracture. Therefore, spring fatigue testing simulates actual working conditions, applies alternating loads of a certain frequency and amplitude, observes and records the fatigue behavior of the spring under specific conditions, and thus evaluates its fatigue life and reliability. To this end, many existing technologies have developed devices for spring tensile fatigue testing, such as:

[0003] CN202420617159.7 discloses a spring fatigue testing device (publication date: 2024-4-26); CN202421149893.1 discloses a fatigue testing device for automated production of flat wire springs (publication date: 2024-6-28); the methods of these traditional technologies are to control the loading device to apply a periodically changing load to the spring to simulate the stress state in actual work; after the test, based on the set number of stretching executions, or using sensors to monitor the stress, strain, displacement and other parameters of the spring, the performance changes during the fatigue process are analyzed in a manual or automated form.

[0004] However, in practical applications, in some scenarios, springs not only need to reciprocate and retract, but also need to be driven by rotation. This composite force condition places higher demands on the fatigue performance of springs. For example, in some precision machinery or power transmission systems, springs are simultaneously subjected to multiple forces such as tension, compression and torsion, and the combined effect of these forces will accelerate the fatigue process of the springs.

[0005] Only reciprocating expansion and contraction fatigue testing cannot fully evaluate the fatigue performance of springs under complex stress conditions. The torsional force generated by the rotary drive may cause additional stress and strain inside the spring, thereby accelerating the initiation and propagation of fatigue cracks.

[0006] To this end, the present invention proposes a spring fatigue testing assembly and an integrated fatigue testing machine. Summary of the invention

[0007] In view of this, the embodiments of the present invention hope to provide a fatigue test assembly and an integrated fatigue test machine for a spring to solve or alleviate the technical problems existing in the prior art, namely, how to simultaneously perform tensile and rotational stress fatigue tests on the tested spring, and at least provide a beneficial option for this; the technical solution of the present invention is implemented as follows:

[0008] First, fatigue test components for springs:

[0009] It includes a frame 4 and the following components arranged in the frame 4:

[0010] 1) A bearing assembly 3 for bearing the spring to be tested;

[0011] 2) a linear drive member 2 for driving the bearing assembly 3 to move linearly along the axial direction of the tested spring;

[0012] 3) An adjusting unit 5 for driving the bearing assembly 3 to rotate axially along the spring to be tested.

[0013] When in use, the spring to be tested is placed on the bearing assembly 3. Based on the set linear position (i.e., testing for tensile properties) and rotational stroke (i.e., testing for stress properties) of the spring to be tested, the linear drive 2 and the adjustment unit 5 regularly adjust the linear position and rotational stroke of the spring to achieve the test in the form of counting.

[0014] In one embodiment, the linear drive member 2 is a screw rod, which is driven to rotate by the first rotating member 1, and the shaft head of the screw rod is rotatably matched with a fixed block 6 fixed on the frame 4;

[0015] The linear transmission on the screw rod is matched with the bearing assembly 3.

[0016] The first rotating member 1 is a first motor, and the output shaft of the first motor is fixedly connected to the shaft head of the screw rod.

[0017] In one embodiment, the bearing assembly 3 includes a sleeve 302 for sleeve-mounting the tested spring, the sleeve 302 is internally embedded and rotatably matched with a moving nut, and then the sleeve 302 is linearly transmitted with the linear drive member 2 (screw) through the moving nut.

[0018] One end of the tested spring is sleeved outside the sleeve 302 , and the other end is clamped in the annular groove 601 of the fixing block 6 .

[0019] In one embodiment, the adjustment unit 5 includes a second rotating member 501 and a driving gear 502 driven to rotate, and a driven gear 301 is fixedly disposed on the outside of the sleeve 302, and the driven gear 301 is meshed with the driving gear 502. Further, when the sleeve 302 adjusts the linear position of the spring, based on the rotation of the driving gear 502 of the adjustment unit 5, the driven gear 301 and the sleeve 302 can be controlled to rotate, thereby adjusting the rotation stroke of the spring.

[0020] The second rotating member 501 is a second motor, and the output shaft of the second motor is fixedly connected to the driving gear 502 .

[0021] In one embodiment, the driving gear 502 and the driven gear 301 are bevel gear trains in the form of idler gears.

[0022] Second, integrated fatigue testing machine:

[0023] It comprises a sealed housing 7 and a fatigue test assembly as described above installed in the sealed housing 7; wherein:

[0024] (1) Sealed housing 7: provides a closed test environment to prevent external factors from affecting the test process and ensure the temperature control effect during the test process.

[0025] (2) Heating device 8: such as an electric heating tube, a hot air blower or a heating belt, used to increase the temperature inside the casing during the test to simulate the spring performance test in a high temperature environment.

[0026] (3) Refrigeration device 9: such as an evaporative air cooler, a negative pressure fan or an evaporator, used to reduce the temperature inside the casing and simulate the spring performance test in a low temperature environment.

[0027] Furthermore, the integrated fatigue testing machine can further introduce high and low temperature test requirements for the springs based on the above-mentioned fatigue testing components for the springs.

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

[0029] 1. Comprehensive testing capability: The present invention integrates two stress testing functions, namely tensile and rotational, and can comprehensively evaluate the fatigue performance and reliability of springs under compound stress conditions. By simulating the tensile and torsional stresses that may be encountered in actual use, the present invention can more accurately predict the performance of springs in actual applications.

[0030] 2. High precision and stability: The linear drive and adjustment unit of the present invention adopts a precise mechanical structure and transmission mode, ensuring high precision and stability during the test. The gear transmission mode has the advantages of accurate transmission ratio, high transmission efficiency, and large load-bearing capacity, which further improves the accuracy and reliability of the test.

[0031] 3. High and low temperature environment simulation: The present invention can simulate high and low temperature environments, further expanding the application scope of the test. By testing in high and low temperature environments, the performance of the spring under different temperature conditions can be more comprehensively evaluated. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It is a three-dimensional schematic diagram of the components of the present invention;

[0034] Figure 2 It is a three-dimensional schematic diagram of the adjustment unit of the present invention;

[0035] Figure 3 For the present invention Figure 3 Schematic diagram of the enlarged view of area A (and the details of the load-bearing components);

[0036] Figure 4 It is a schematic diagram of a rack of the present invention;

[0037] Figure 5 It is a three-dimensional schematic diagram of the integrated fatigue testing machine of the present invention.

[0038] Figure numerals: 1, first rotating member; 2, linear driving member; 3, bearing assembly; 301, driven gear; 302, sleeve; 4, frame; 5, adjustment unit; 501, second rotating member; 502, driving gear; 6, fixing block; 601, annular groove. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below;

[0040] Embodiment 1: In the prior art, only reciprocating telescopic fatigue testing cannot fully evaluate the fatigue performance of springs under complex stress conditions. The torsional force generated by the rotary drive may cause additional stress and strain inside the spring, thereby accelerating the initiation and propagation of fatigue cracks. If the influence of the rotary drive is not fully considered during the spring design process, the product may fail prematurely in actual use. Without data support from rotary drive tests, it is difficult for designers to accurately predict the fatigue life and reliability of the spring in an actual working environment.

[0041] To do this, see Figure 1-4 This specific implementation will provide a solution for a spring fatigue test assembly to solve the above technical problems:

[0042] The fatigue test assembly for the spring is mainly composed of a frame 4, a bearing assembly 3, a linear drive 2 and an adjustment unit 5. In actual operation, the spring to be tested is first placed on the bearing assembly 3, and the bearing assembly is designed with a fixing device that matches the spring to ensure the stability and accuracy of the spring during the test. Subsequently, the linear position and rotation stroke of the spring are set according to the test requirements. The linear drive 2, such as a servo motor or a hydraulic cylinder, moves linearly along the axial direction of the spring through a precise control system to simulate the stretching and compression process of the spring in actual application. At the same time, the adjustment unit 5 may use a rotating motor or a reducer to drive the bearing assembly 3 and the spring thereon to rotate according to the set rotation stroke to simulate the working state of the spring under torsional stress. The entire test process is precisely controlled by the control system, and the number of test cycles is recorded in the form of a count until the spring fails due to fatigue.

[0043] Specifically: The design principle of the fatigue test assembly is based on simulating the stress state of the spring in actual use, and comprehensively evaluates the fatigue performance of the spring under complex stress conditions by combining linear drive and rotation drive. The linear drive 2 simulates the stress changes of the spring during the stretching and compression process by precisely controlling the displacement and speed; while the adjustment unit 5 simulates the stress state of the spring during the torsion process by controlling the rotation angle and speed. The superposition of these two stresses is closer to the complex stress conditions of the spring in actual application, so that the fatigue life and reliability of the spring can be predicted more accurately.

[0044] It can be understood that in the above scheme provided in this embodiment: the fatigue test assembly for the spring functionally realizes a comprehensive test of the spring under compound stress conditions, thereby improving the accuracy and reliability of the test results. By simultaneously applying linear tension / compression and rotational torsion stresses, the assembly can simulate the stress state of the spring in a variety of application scenarios, such as automotive suspension systems, vibration isolation devices for aerospace equipment, etc. This comprehensive testing method helps designers to more accurately evaluate the performance of the spring, optimize product design, and improve product durability and safety. In addition, the automated control system and counting function of the assembly make the testing process more efficient and convenient, reduce human errors, and improve the repeatability of the test.

[0045] In the technical solution provided in this embodiment, please refer to Figure 1 :The linear drive member 2 is specifically in the form of a screw, which is driven to rotate by the first rotating member 1, that is, the first motor. The output shaft of the first motor is fixedly connected to the shaft head of the screw to ensure that the screw can rotate with the rotation of the motor output shaft. The shaft head of the screw is rotatably matched in the fixed block 6 fixed on the frame 4. This design ensures the stability and accuracy of the screw during rotation. The bearing assembly 3 cooperates with the linear transmission of the screw, which means that when the screw rotates, the bearing assembly 3 will move linearly along the axial direction of the screw, thereby realizing the stretching and compression of the tested spring.

[0046] Specifically: Screw drive is a precision transmission method, and its principle is to convert rotational motion into linear motion by using the threaded fit between the screw and the nut. In this embodiment, the first motor serves as a power source to drive the screw to rotate, and the thread on the screw cooperates with the nut inside the bearing assembly 3, thereby converting the rotational motion into the linear movement of the bearing assembly 3. By controlling the speed and direction of the motor, the moving speed and direction of the bearing assembly 3 can be accurately controlled, thereby achieving accurate stretching and compression of the tested spring.

[0047] It is understandable that in the above scheme provided in this embodiment: the use of screw drive as a linear drive mode has the advantages of high transmission accuracy, smooth operation, low noise, etc. In the present spring fatigue test assembly, the screw drive not only ensures the stability and accuracy of the bearing assembly 3 during the stretching and compression process, but also improves the reliability and repeatability of the test. At the same time, since the screw drive has a self-locking property, it can prevent the bearing assembly 3 from accidentally moving due to external force during the test to a certain extent, ensuring the safety and accuracy of the test.

[0048] In the technical solution provided in this embodiment, please refer to Figures 3-4The bearing assembly 3 includes a sleeve 302 for sleeve-mounting the tested spring. The sleeve 302 is internally embedded and rotatably matched with a moving nut. This design enables the sleeve 302 to achieve linear transmission cooperation with the linear drive member 2, i.e., the screw, through the moving nut. When the screw rotates, the moving nut will move along the axial direction of the screw, thereby driving the sleeve 302 and the tested spring thereon to move linearly. One end of the tested spring is sleeved outside the sleeve 302, ensuring the stability and centering of the spring during the test; the other end is clamped in the annular groove 601 of the fixed block 6. This design not only ensures the fixity of the spring during the test, but also allows the spring to freely extend or shorten when stretched or compressed.

[0049] Specifically: The bearing assembly 3 realizes effective connection and transmission with the tested spring through the cooperation of the sleeve 302 and the moving nut. When the screw rotates, the moving nut will move linearly along the thread of the screw. Since the moving nut is embedded and rotated in the sleeve 302, it will drive the sleeve 302 and the tested spring thereon to move together. This transmission method not only ensures the accuracy and stability of the transmission, but also makes the testing process simpler and more efficient. At the same time, one end of the tested spring is sleeved outside the sleeve 302, and the other end is clamped in the annular groove 601 of the fixed block 6. This design ensures the uniformity and centering of the force on the spring during the test, and improves the accuracy and reliability of the test results.

[0050] It can be understood that in the above scheme provided in the present embodiment: the design of the above-mentioned bearing assembly 3 fully considers the stress state and stability requirements of the tested spring during the test process. Through the cooperation of the sleeve 302 and the movable nut, effective connection and precise transmission with the tested spring are achieved, ensuring the stability and accuracy of the test process. At the same time, one end of the tested spring is sleeved outside the sleeve 302, and the other end is clamped in the annular groove 601 of the fixed block 6. Such a design not only facilitates the installation and disassembly of the spring, but also improves the convenience and efficiency of the test. In addition, the structural design of the bearing assembly 3 is compact and reasonable, making the entire test assembly more portable and easy to carry, which is convenient for testing in different occasions.

[0051] In the technical solution provided in this embodiment, please refer to Figures 2 to 4:The adjusting unit 5 is designed to drive the bearing assembly 3 and the tested spring thereon to rotate. The adjusting unit 5 includes a second rotating member 501, i.e., a second motor, and a driving gear 502 driven by the second motor. A driven gear 301 is fixedly provided on the outside of the sleeve 302, and the driven gear 301 is meshed with the driving gear 502. When the second motor is started, its output shaft will drive the driving gear 502 to rotate. Since the driving gear 502 is meshed with the driven gear 301, the driven gear 301 and the sleeve 302 will be driven to rotate together. In this way, when the sleeve 302 adjusts the linear position of the spring under the action of the linear drive member 2, the adjusting unit 5 can control the driven gear 301 and the sleeve 302 to rotate through the rotation of the driving gear 502, thereby adjusting the rotation stroke of the spring.

[0052] It should be pointed out that in order to simplify the display structure in the figure, the driven gear 301 and the driving gear 502 are hidden.

[0053] Specifically: The working principle of the adjustment unit 5 is based on the gear transmission principle. The driving gear 502 is driven to rotate by the second motor. When the driving gear 502 rotates, it drives the driven gear 301 meshing with it to rotate. Since the driven gear 301 is fixed to the outside of the sleeve 302, it drives the sleeve 302 and the tested spring thereon to rotate together. By controlling the speed and direction of the second motor, the rotation speed and direction of the sleeve 302 can be accurately controlled, thereby achieving accurate adjustment of the rotation stroke of the tested spring.

[0054] It can be understood that in the above scheme provided in this embodiment: the design of the adjustment unit 5 enables the fatigue test assembly for the spring to achieve a comprehensive test of the tested spring under compound stress conditions. Through the driving action of the adjustment unit 5, the torsional stress state of the spring in actual application can be simulated, so as to more accurately evaluate the fatigue performance and reliability of the spring. At the same time, since the adjustment unit 5 adopts a gear transmission method, it has the advantages of accurate transmission ratio, high transmission efficiency, and large load-bearing capacity, which ensures the stability and accuracy of the test process.

[0055] In the technical solution provided in this embodiment, please refer to Figure 3 :In this embodiment, the driving gear 502 and the driven gear 301 are bevel gear systems in the form of idler gears. Both the driving gear 502 and the driven gear 301 are bevel gears, and they are both idler gears. This design allows the driving gear 502 and the driven gear 301 to transmit on vertical or intersecting axes, thereby providing greater flexibility and adaptability. When the second rotating member 501 (such as the second motor) drives the driving gear 502 to rotate, it further drives the driven gear 301 and the sleeve 302 to rotate, thereby achieving the adjustment of the rotation stroke of the tested spring.

[0056] Specifically: The bevel gear system in the form of an idler is a commonly used gear transmission method. Its principle is to use the tooth shape of the bevel gear as an intervention of the idler to achieve transmission on intersecting axes or perpendicular axes. In this embodiment, the driving gear 502 and the driven gear 301 are both bevel gears, and the transmission ratio between them is adjusted by the idler. Due to the tooth shape design of the bevel gears, they can be transmitted on intersecting or perpendicular axes, thereby realizing the rotation drive of the sleeve 302 and the tested spring thereon.

[0057] In this embodiment, the above device can also introduce an existing sensor system for spring fatigue testing. Since these sensors and their connection methods belong to the existing technology, they will not be described in detail here.

[0058] In this embodiment, all electrical components of the device as a whole rely on AC power for energy supply; specifically, the electrical components of the device as a whole are conventionally electrically connected to the battery output port through devices such as relays, transformers and button panels to meet the energy supply requirements of all electrical components of the device.

[0059] Specifically, a controller is also provided on the outside of the device, which is used to connect and control all electrical components of the device as a whole to be driven according to a pre-set program as a preset value and a driving mode; it should be pointed out that the above-mentioned driving mode corresponds to the corresponding start and stop time intervals, speed, power and other output parameters between the relevant electrical components mentioned above, that is, it meets the requirements of the relevant electrical components mentioned above to drive the relevant mechanical devices to operate according to the functions described therein.

[0060] Preferably, the controller is a PLC controller, which completes the above control requirements through conventional PLC control modes such as ladder diagrams, sequential function diagrams, function block diagrams, instruction tables or structured texts; it should be pointed out that the output parameters such as the start and stop time intervals, speed, power, etc. of the electrical components or other power components driven by its programming are non-limiting; specifically, the relevant drive control is adjusted according to actual usage requirements.

[0061] In summary, in view of the related problems in the traditional technology, this specific implementation method is based on the above-mentioned spring fatigue test assembly and integrated fatigue test machine, and adopts the following technical means or features to achieve the solution:

[0062] (1) Realization of tensile stress: The linear drive member 2 (such as a screw) is driven to rotate by the first rotating member 1 (such as a first motor). The linear drive on the screw is matched with a bearing assembly 3, and the bearing assembly 3 includes a sleeve 302 for sleeve-mounting the tested spring.

[0063] When the lead screw rotates, the moving nut will move along the axial direction of the lead screw. Since the moving nut is embedded and rotatably fitted inside the sleeve 302, it will drive the sleeve 302 and the tested spring thereon to move linearly together, thereby achieving the stretching and compression of the spring.

[0064] (2) Realization of rotational stress: The adjustment unit 5 includes a second rotating member 501 (such as a second motor) and a driving gear 502 driven to rotate by the second motor. A driven gear 301 is fixed to the outside of the sleeve 302, and the driven gear 301 is meshed with the driving gear 502. When the second motor is started, its output shaft drives the driving gear 502 to rotate. Since the driving gear 502 is meshed with the driven gear 301, the driven gear 301 and the sleeve 302 are driven to rotate together.

[0065] In this way, the sleeve 302 and the tested spring thereon will rotate along with the rotation of the sleeve, thereby achieving a torsional stress test on the spring.

[0066] (3) Performing tensile and rotational stress fatigue tests simultaneously: Through the coordinated action of the linear drive 2 and the adjustment unit 5, it is possible to simultaneously apply tensile and rotational stresses to the tested spring.

[0067] Specifically, when the linear drive 2 drives the sleeve 302 and the spring thereon to move linearly, the adjustment unit 5 can simultaneously drive the sleeve 302 and the spring thereon to rotate. In this way, the tested spring will be subjected to both tensile and rotational stresses at the same time, thereby simulating the composite stress conditions that may be encountered in actual use.

[0068] Embodiment 2, as Figure 5 As shown; based on the fatigue testing assembly disclosed in the first embodiment, this embodiment further discloses an integrated fatigue testing machine:

[0069] It comprises a sealed housing 7 and a fatigue testing assembly as described in the first embodiment installed in the sealed housing 7; wherein:

[0070] (1) Sealed housing 7: provides a closed test environment to prevent external factors from affecting the test process and ensure the temperature control effect during the test process.

[0071] (2) Heating device 8: such as an electric heating tube, a hot air blower or a heating belt, used to increase the temperature inside the casing during the test to simulate the spring performance test in a high temperature environment.

[0072] (3) Refrigeration device 9: such as an evaporative air cooler, a negative pressure fan or an evaporator, used to reduce the temperature inside the casing and simulate the spring performance test in a low temperature environment.

[0073] Furthermore, the integrated fatigue testing machine can further introduce high and low temperature test requirements for the springs based on the above-mentioned fatigue testing components for the springs.

[0074] It is understandable that the integrated fatigue testing machine can not only test the fatigue performance of springs, but also simulate high and low temperature environments to comprehensively evaluate the performance of springs under different temperature conditions. Through integrated design, the equipment footprint and operation complexity are reduced, and the test efficiency is improved. It is suitable for aerospace, automobile, machinery, electronics and other fields to test the durability and reliability of springs and other materials under complex working conditions.

[0075] Furthermore, the specific working process of the integrated fatigue testing machine disclosed in this embodiment in practical application is as follows:

[0076] S1, Assembly and test parameter setting:

[0077] S100, Power on: Ensure that all electrical components of the integrated fatigue tester are properly connected and connected to the mains. Check whether the controller (such as a PLC controller) has been correctly programmed and is in standby mode.

[0078] S101, install the spring to be tested: place the spring to be tested on the sleeve 302 of the bearing assembly 3, ensure that one end of the spring is sleeved outside the sleeve 302, and the other end is clamped in the annular groove 601 of the fixing block 6. Check whether the spring is installed firmly to ensure that it will not slide or fall off during the test.

[0079] S102, perform micro debugging: first reset the position reference of the mechanism to zero, and ensure that all transmission components are in the initial state. According to the requirements of the drawing, set the position and rotation stroke of the spring test. This can be done by setting the output parameters of the linear drive 2 and the adjustment unit 5 through the controller.

[0080] S103, after the setting is completed, test run the fatigue test: start the fatigue tester to confirm whether the tested spring is stretched and rotated according to the established settings. Observe the running status of the spring. If there is any abnormality (such as jamming, offset, etc.), re-debug; if everything is normal, proceed to the next step.

[0081] S2, set the ambient temperature of the high and low temperature testing machine

[0082] S200, power on the test machine: Ensure that all electrical components of the high and low temperature test machine are properly connected and connected to the mains. Check whether the control system of the test machine is in normal working condition.

[0083] S201, set the operating temperature: according to the high or low temperature test requirements of the product, set the operating temperature of the test machine through the PLC interface or the control panel of the test machine. Ensure that the set temperature value is within the controllable range of the test machine and meets the requirements of the test standard.

[0084] S202, start the high and low temperature test machine: after confirming that the temperature setting is correct, start the high and low temperature test machine and start the heating or cooling process. Wait for the test machine to reach the set temperature and maintain a constant temperature.

[0085] S3, fatigue test can be carried out only after the high and low temperature testing machine reaches the set temperature and maintains a constant temperature state:

[0086] S300: After the test machine reaches the set temperature and maintains a constant temperature, confirm that the test environment has stabilized.

[0087] S301, check whether the tested spring is deformed or displaced due to temperature change, and make corresponding adjustments if necessary.

[0088] S4, high and low temperature testing machine, under the premise of constant temperature, start the fatigue testing machine:

[0089] S400: After confirming that the test environment is stable, start the fatigue testing machine.

[0090] S401, the controller controls the linear drive member 2 and the adjustment unit 5 to work simultaneously, so as to apply tensile and rotational stresses to the tested spring.

[0091] S5, the product is in the high and low temperature test room, according to the customer's requirements, in a high or low temperature environment, and the fatigue testing machine performs fatigue life tests on the spring:

[0092] S500, during the test, closely observe the condition of the spring being tested.

[0093] S501, record the number of test cycles and the fatigue failure of the spring.

[0094] S502: If you need to adjust the test parameters or stop the test, you can perform corresponding operations through the controller.

[0095] S503, after the test is completed, the fatigue testing machine and the high and low temperature testing machine are turned off, the tested spring is taken out, and corresponding data processing and analysis are performed.

[0096] Through the above steps S1 to S5, a comprehensive test of the spring under complex stress conditions and different temperature environments can be achieved, thereby more accurately evaluating the fatigue performance and reliability of the spring.

[0097] Embodiment 3: This embodiment further discloses an embedded C language control program of the integrated fatigue testing machine disclosed in Embodiment 2, wherein:

[0098] (1)PLC controller configuration:

[0099] (1.1)PLC model: Siemens S7-1200;

[0100] (1.2)I / O configuration:

[0101] AI (input): stress sensor;

[0102] AO (output): not used directly;

[0103] DI (digital input): start / stop button, emergency stop button;

[0104] DO (digital output): first rotating member 1 control;

[0105] (1.3) Program structure:

[0106] Variable declaration;

[0107] initialization;

[0108] Main loop;

[0109] Interrupt processing (emergency stop button);

[0110] (2)Procedure content:

[0111] / / Preset macro definition and type (according to PLC API definition)

[0112] #define MAX_CYCLES10000 / / Maximum number of test cycles

[0113] #define LINEAR_SPEED 100 / / Linear drive speed (unit: mm / s)

[0114] #define ROTATIONAL_SPEED 50 / / Adjust unit speed (unit: deg / s)

[0115] / / Variable declaration

[0116] int testCycleCount = 0; / / Number of test cycles

[0117] BOOL testRunning=FALSE; / / Test running status BOOL emergencyStop=FALSE; / / Emergency stop status

[0118] / / Initialization function

[0119] void init(){

[0120] / / Initialize PLC I / O, communication

[0121] / / Set the initial state of the linear drive and adjustment unit

[0122] setLinearDriveState(OFF);

[0123] setRotationUnitState(OFF);

[0124] }

[0125] / / Main loop function

[0126] void mainLoop(){

[0127] / / Emergency stop

[0128] if(readDIButton(EMERGENCY_STOP_BUTTON)){

[0129] emergencyStop = TRUE;

[0130] stopTest();

[0131] return;

[0132] }

[0133] / / start up

[0134] if(readDIButton(START_BUTTON)&&!testRunning){

[0135] testRunning = TRUE;

[0136] testCycleCount = 0;

[0137] startTest();

[0138] }

[0139] / / If the test is running

[0140] if(testRunning){

[0141] / / Execute linear drive

[0142] executeLinearDrive();

[0143] / / Execute the adjustment unit

[0144] executeRotationUnit();

[0145] / / Increase the test loop count

[0146] testCycleCount++;

[0147] / / Check if the maximum number of cycles has been reached or the spring has failed due to fatigue

[0148] if(testCycleCount>=MAX_CYCLES||checkSpringFailure()){

[0149] stopTest();

[0150] }

[0151] }

[0152] }

[0153] / / Start the test function

[0154] void startTest(){

[0155] setLinearDriveState(ON);

[0156] setRotationUnitState(ON);

[0157] / / Set the speed of the linear drive and adjustment unit

[0158] setLinearDriveSpeed(LINEAR_SPEED);

[0159] setRotationUnitSpeed(ROTATIONAL_SPEED);}

[0160] / / Stop the test function

[0161] void stopTest(){

[0162] testRunning = FALSE;

[0163] setLinearDriveState(OFF);

[0164] setRotationUnitState(OFF);

[0165] / / Execute record data

[0166] }

[0167] / / Linear drive execution function

[0168] void executeLinearDrive(){

[0169] / / Control the linear drive to perform stretching / compression operations

[0170] }

[0171] / / Adjustment unit execution function

[0172] void executeRotationUnit(){

[0173] / / Control the adjustment unit to rotate

[0174] }

[0175] / / Check spring fatigue failure function

[0176] BOOL checkSpringFailure(){

[0177] / / Check if the spring is fatigued

[0178] return FALSE;

[0179] }

[0180] / / PLC program entry

[0181] int main(){

[0182] init(); / / initialization

[0183] while(1){

[0184] mainLoop(); / / Main loop

[0185] }

[0186] return 0;

[0187] }

[0188] In the above program, variable declarations define variables used to store the test cycle number, test run status, and emergency stop status.

[0189] In the init function, the PLC's I / O modules and communication interfaces are initialized, and the initial states of the linear drive and adjustment unit are set.

[0190] In the mainLoop function, the status of the emergency stop button and the start button are continuously checked. If the emergency stop button is pressed, the test is stopped immediately; if the start button is pressed and the test is not running, the test is started. During the test run, the linear drive and the adjustment unit are controlled to perform tension / compression and rotation operations, and the test cycle count is increased. The test is stopped when the maximum number of cycles is reached or the spring fails due to fatigue.

[0191] The startTest and stopTest functions are used to start and stop the test respectively, and set the status and speed parameters of the linear drive and adjustment unit.

[0192] The executeLinearDrive and executeRotationUnit functions control the execution of the linear drive and the rotation unit, respectively.

[0193] The checkSpringFailure function is used to check whether the spring has fatigue failure.

[0194] The above-mentioned embodiments only express the implementation methods of the relevant practical applications of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A fatigue test assembly for a spring, characterized in that: It comprises a frame (4) and a device arranged in the frame (4), A bearing assembly (3) for bearing the spring to be tested; A linear drive member (2) for driving the bearing assembly (3) to move linearly along the axial direction of the spring being tested; An adjusting unit (5) is used for driving the bearing assembly (3) to rotate along the axial direction of the spring being tested.

2. The fatigue test assembly according to claim 1, characterized in that: The linear drive member (2) is a screw rod, which is driven to rotate by the first rotating member (1), and the shaft head of the screw rod is rotatably engaged with a fixed block (6) fixed on the frame (4); The linear transmission on the screw rod is matched with the bearing assembly (3).

3. The fatigue testing assembly according to claim 2, characterized in that: The first rotating member (1) is a first motor, and the output shaft of the first motor is fixedly connected to the shaft head of the screw rod.

4. The fatigue testing assembly according to claim 1, characterized in that: The bearing assembly (3) comprises a sleeve (302) for sleeve-mounting a spring to be tested, and the sleeve (302) cooperates with the linear drive member (2) (screw) in linear transmission.

5. The fatigue testing assembly according to claim 4, characterized in that: One end of the tested spring is sleeved outside the sleeve (302), and the other end is clamped in the annular groove (601) of the fixing block (6).

6. The fatigue testing assembly according to claim 3, characterized in that: The adjustment unit (5) comprises a second rotating member (501) and a driving gear (502) driven to rotate by the second rotating member. A driven gear (301) is fixedly arranged on the outside of the sleeve (302), and the driven gear (301) is meshed with the driving gear (502).

7. The fatigue testing assembly according to claim 5, characterized in that: The second rotating member (501) is a second motor, and the output shaft of the second motor is fixedly connected to the driving gear (502).

8. The fatigue testing assembly according to claim 5, characterized in that: The driving gear (502) and the driven gear (301) are bevel gear trains in the form of idler gears.

9. Integrated fatigue testing machine, characterized in that, It comprises a sealed housing (7) and a fatigue testing assembly according to any one of claims 1 to 8 installed in the sealed housing (7); A heating device (8) and a refrigeration device (9) for increasing or decreasing the temperature are installed in the sealed casing (7).

10. The fatigue testing machine according to claim 9, characterized in that: The heating device (8) is an electric heating tube, a hot air blower or a heating belt; the cooling device (9) is an evaporative air cooler, a negative pressure blower or an evaporator.

Images