A spring deformation collapse detection method, system, and device

Abstract

The application relates to the technical field of spring deformation detection, in particular to a spring deformation and collapse detection method, system and device, which comprises the following steps: randomly selecting a plurality of springs in the same batch of springs produced for deformation and collapse detection; randomly setting an initial tension value sequence in the tension bearing range of the spring, sequentially stretching the spring to a fixed length by using each initial tension value in the initial tension value sequence, then unloading the force to make the spring rebound to a free state, and repeating the process until the spring completely collapses; determining the deformation migration amount and the elasticity of the spring corresponding to the initial tension value sequence in each cycle; based on the time point difference of the change trend between the deformation migration amount and the elasticity in all the cycle processes of the spring collapse, and in combination with the complete collapse time of the spring, the deformation and collapse coefficient of the spring is obtained, and the deformation and collapse of the same batch of springs produced is detected. Therefore, the precision of the spring deformation and collapse detection is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of spring deformation detection, in particular to a spring deformation collapse detection method, system and device. BACKGROUND

[0002] Springs bear repeated external force loading in the working process. After a long time of use, the material will appear fatigue phenomenon, eventually leading to rupture or permanent deformation. The stress distribution and deformation performance of the spring are important factors affecting its service life. The existing technology can measure the state of the spring during work by using strain gauges and pressure sensors, so as to evaluate whether the performance meets the design requirements. If it exceeds the safety range of the design, plastic deformation or fatigue failure may occur in subsequent use.

[0003] The existing detection method generally applies the maximum load to the spring to simulate the spring in the extreme working condition environment, and detects the collapse deformation of the spring by the elastic change of the spring in the extreme working condition and the deformation amount of the spring coil. However, in the actual use environment of the spring, it is used in the working condition environment with frequent stress changes most of the time, which is not enough to evaluate the actual use performance of the spring. If the random load is applied to the spring to simulate the test environment of the spring in the normal working condition, the reliability of the spring deformation collapse detection may be low due to irregular load and lack of unified detection standard, which affects the accuracy of the spring production quality evaluation. SUMMARY

[0004] In order to solve the above technical problems, the purpose of the present application is to provide a spring deformation collapse detection method, system and device, and the technical scheme adopted is as follows:

[0005] In the first aspect, the present application provides a spring deformation collapse detection method, which comprises the following steps:

[0006] In the same batch of springs produced, an initial tension value sequence is set, and a plurality of springs are randomly selected for cyclic multiple times of tensile and elastic detection;

[0007] The tension sensitivity of each position point of the spring is determined by the change of the deformation amount of each position point on the spring in the test process and the difference between the tension and the initial tension value when stretched to a fixed length. Based on the change degree of the tension sensitivity of each position point on the spring in one cycle, and in combination with the distribution of each initial tension value in the initial tension value sequence, the deformation migration amount corresponding to the initial tension value sequence of the spring is determined.

[0008] The difference in the stress change trend at different stages in each stretching of the spring and the stress change rate of each stretching are analyzed to determine the stretching difficulty change rate of each stretching of the spring.

[0009] Analyzing the change trend of the tension difficulty change rate in all the secondary tensions of one cycle, and combining the change rate of the tension of the spring during tension, the elasticity measure corresponding to the initial tension value sequence of the spring per cycle is obtained;

[0010] Based on the time point difference between the change trend of the deformation migration amount and the elasticity measure, and combining the complete collapse time of the spring, the deformation collapse coefficient of the spring is obtained, and the deformation collapse of the same batch of springs produced is detected.

[0011] In one embodiment, the determination of the tension sensitivity of each position point of the spring during each tension includes:

[0012] The dispersion degree of the deformation amount of each position point of the spring per unit time during tension and rebound is determined, the difference between the tension and the initial tension value when the spring is stretched to a fixed length is recorded as a first difference, and the tension sensitivity is a ratio of the dispersion degree and the first difference.

[0013] In one embodiment, the determination of the deformation migration amount corresponding to the initial tension value sequence of the spring per cycle includes:

[0014] For each tension of the spring, all the position points are arranged in descending order of tension sensitivity, and the arrangement position sequence corresponding to each position point of each tension is obtained.

[0015] The same initial tension value in the initial tension value sequence is taken as a class, the ratio of the number of initial tension values in each class of initial tension values to the total number of initial tension values in the initial tension value sequence is calculated, and is recorded as a first ratio. For the initial tension value sequence per cycle, the dispersion degree of the arrangement position sequence corresponding to each position point of the spring in all the secondary tensions of each class of initial tension values is calculated, and is recorded as a first dispersion degree.

[0016] Based on the first ratio and the first dispersion degree, the deformation migration amount corresponding to the initial tension value sequence of the spring per cycle is determined.

[0017] In one embodiment, the further determination of the deformation migration amount includes:

[0018] The product of the first ratio and the first dispersion degree is calculated, and the average value of the product of all the position points of the spring of all the classes of initial tension values corresponding to the initial tension value sequence per cycle is taken as the deformation migration amount corresponding to the initial tension value sequence per cycle.

[0019] In one embodiment, the determination of the tension difficulty change rate of each tension of the spring includes:

[0020] The stretching process of the spring is divided into a spiral unwinding dominant segment and a medium loading segment, a force fitting curve of the spring in the spiral unwinding dominant segment and the medium loading segment is respectively determined, and a difference between average slopes of the force fitting curves of the spiral unwinding dominant segment and the medium loading segment is calculated and recorded as a second difference;

[0021] A derivative curve of the force fitting curve of the medium loading segment is determined, a product of a maximum function value of the derivative curve and a slope corresponding to the maximum function value is calculated and recorded as a first product, and the stretching difficulty change rate is a ratio of the first product to the second difference.

[0022] In one embodiment, the obtaining of the elasticity measure corresponding to the initial tension value sequence of the spring per cycle includes:

[0023] An average absolute value of slopes of fitting curves of the stretching difficulty change rates in all the secondary stretchings corresponding to the initial tension value sequence per cycle is determined, and an average value of the stretching difficulty change rates is determined;

[0024] A product of the average absolute value of the slopes and the average value is calculated and recorded as a second product, a change rate of a maximum tension of the spring stretched to the spiral unwinding dominant segment in all the secondary stretchings is determined, an inverse of a ratio of the change rate of the maximum tension to the second product is calculated, an index of an exponential function with a natural constant as a base number is taken as the inverse, and a calculation result of the exponential function is taken as the elasticity measure corresponding to the initial tension value sequence of the spring per cycle.

[0025] In one embodiment, the obtaining of the deformation collapse coefficient of the spring includes:

[0026] A time point t1 corresponding to a maximum value in a derivative curve of a fitting curve of the deformation transition amount of the spring in all the secondary cycles is determined, a time point t2 corresponding to a maximum value in a derivative curve of a fitting curve of the elasticity measure of the spring in all the secondary cycles is determined, a time point t3 closest to the time point t1 and the time point t2 is obtained, and the time point t3 is taken as a deformation collapse point of the spring;

[0027] A normalized value of a ratio of a time length corresponding to the deformation collapse point of the spring to a complete collapse time length of the spring is calculated and taken as the deformation collapse coefficient of the spring.

[0028] In one embodiment, the deformation collapse detection on the springs produced in the same batch includes: if the deformation collapse coefficients of the extracted springs are all less than a preset threshold value, it is determined that the quality of the springs produced in the same batch is unqualified and the deformation collapse risk is more likely to occur, otherwise, it is determined that the quality of the springs produced in the same batch is qualified.

[0029] In a second aspect, the embodiments of the present application also provide a spring deformation collapse detection device, wherein the device stores a computer program, and the computer program is executed by a processor to implement any of the spring deformation collapse detection methods.

[0030] In a third aspect, the embodiments of the present application also provide a spring deformation collapse detection system, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, and the processor executes the computer program to implement the steps of any of the methods.

[0031] The present application has at least the following beneficial effects:

[0032] The present application determines the tension sensitivity of each position point of the spring during each stretching of the spring by analyzing the dispersion degree of the deformation amount of each position point of the spring per unit time and the difference between the actual tension and the initial set value, improves the sensing accuracy of the local stress response of the spring material, helps to identify the weak points of the spring, and provides data support for the spring deformation collapse detection by early warning potential structural defects; further, the present application determines the deformation migration amount corresponding to the initial tension value sequence of the spring per cycle, enhances the monitoring capability of the cumulative plastic deformation of the spring, and solves the problem that the traditional static detection cannot capture the gradual deformation under cyclic loading; the present application divides the stretching process of the spring into a spiral expansion dominant segment and a mid-term loading segment, obtains the stretching difficulty change rate of each stretching of the spring, helps to locate the key stage of performance degradation of the spring, quantifies the change degree of the stretching difficulty of the spring, and improves the accuracy of the subsequent spring deformation collapse detection; the present application obtains the elasticity measure corresponding to the initial tension value sequence of the spring per cycle, more comprehensively reflects the energy storage and dissipation characteristics of the spring under cyclic loading, makes the deformation collapse detection of the spring closer to the actual use process of the spring, and improves the credibility of the spring deformation collapse detection; in all the secondary cycles of the spring collapse, based on the time point difference between the change trend of the deformation migration amount and the elasticity measure, combined with the complete collapse time of the spring, the deformation collapse coefficient of the spring is obtained, the deformation collapse detection of the same batch of springs is performed, and the prediction accuracy of the service life of the same batch of springs is significantly improved, and the accuracy of the spring deformation collapse detection is improved. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the drawings needed in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0034] Figure 1A spring deformation collapse detection method provided by an embodiment of the present application;

[0035] Figure 2 A schematic diagram of deformation variable change in a fixed position during spring deformation;

[0036] Figure 3 A schematic diagram of tension change during spring stretching. DETAILED DESCRIPTION

[0037] In order to further illustrate the technical means and effects taken by the present application to achieve the predetermined purposes, the specific embodiments, structures, features and effects of the spring deformation collapse detection method, system and device according to the present application are described in detail as follows in combination with the drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.

[0039] The specific scheme of the spring deformation collapse detection method, system and device provided by the present application is specifically described below in combination with the drawings.

[0040] Please refer to Figure 1 which shows a step flow chart of a spring deformation collapse detection method provided by an embodiment of the present application. The method includes the following steps:

[0041] S1, among the same batch of springs produced, a plurality of springs are randomly selected for deformation collapse detection. An initial tension value sequence is randomly set within the tension bearing range of the spring. Each initial tension value in the initial tension value sequence is used to stretch the spring to a fixed length, and then the force is released to make it rebound to a free state. This process is repeated until the spring completely collapses.

[0042] After industrial production of a batch of springs, the quality of the springs may be problematic due to problems of molten material and stress in the production process of the springs, and the risk of deformation collapse is relatively high. Therefore, it is necessary to detect the deformation collapse of the produced springs. In this embodiment, N springs are randomly selected from the same batch of produced springs, and the N springs are respectively detected for deformation collapse. Specifically,

[0043] The embodiment integrates a servo motor driven tension mechanism, which is matched with a high-precision ball screw and a customized clamp, and a high-range tension sensor in parallel to collect spring force data in real time. Meanwhile, M position points are evenly marked on the spring, and a double-side orthogonal industrial camera is erected, which is equipped with a telecentric lens and a programmable ring light source. Two laser line scanning sensors are arranged orthogonally on both sides of the spring axis, and the resolution is ±0.1 μm, and the scanning frequency is 1 kHz. In the embodiment, the collection time interval of the spring force data is 0.1 s, N=10, and M=5. The implementer can set them according to the actual situation, which is not limited in the embodiment.

[0044] A random initial tension value sequence that meets the independent and identically distributed is generated in advance in the working tension range of the spring. The spring is stretched to a fixed length L by applying each initial tension value in the initial tension value sequence to the spring in turn, and then the force is unloaded to make the spring rebound to a free state. All initial tension values in the initial tension value sequence are applied as a cycle, and the cycle is repeated until the spring is completely broken after the test is stopped. In the embodiment, the fixed length L is twice the length of the spring in the free state, and the implementer can set it according to the actual situation, which is not limited in the embodiment.

[0045] S2, the dispersion degree of the deformation amount of each position point on the spring in unit time during stretching and rebounding, and the difference between the tension when stretched to the fixed length and the initial tension value, are determined to determine the tension sensitivity of each position point on the spring during each stretching. Based on the change degree of the tension sensitivity of each position point on the spring in all times of stretching corresponding to one cycle of the initial tension value sequence, and the frequency of each initial tension value in the initial tension value sequence, the deformation migration amount corresponding to one cycle of the initial tension value sequence is determined.

[0046] The embodiment takes any extracted spring as an example for analysis. The spring is subjected to different random distribution of initial tension in a single cycle, and based on this, the random deformation and failure of the spring under several complex working conditions can be simulated. In the process of applying the initial tension to the spring for stretching and rebounding freely after stretching to the fixed length, the laser line scanning sensor arranged in the embodiment tracks the deformation amount of each position point on the spring in unit time, that is, the change in spatial distance of each position point in unit time, thereby reflecting the deformation of each position point on the spring during the force deformation process of the spring.

[0047] The process of applying an initial tension to the spring once for stretching, and freely rebounding after stretching to a fixed length, is recorded as a first deformation process of the spring. All deformation variable data of all position points in the spring deformation process are obtained, and the dispersion degree of all deformation variables of each position point is calculated. The dispersion degree can be calculated by using variance, standard deviation, coefficient of variation, etc., and the variance is used as the calculation method of the dispersion degree in this embodiment. The fixed position deformation variable change diagram in the spring deformation process is shown in FIG. 8. Figure 2

[0048] The tension sensitivity of each position point of the spring at each stretching is determined, and the specific expression is as follows:

[0049] ; in the formula, is the tension sensitivity of the i-th position point of the spring at the u-th stretching, is the variance of all deformation variables of the i-th position point in the deformation process corresponding to the u-th stretching of the spring, is the tension of the spring at the u-th stretching to the fixed length L, is the initial tension of the u-th stretching of the spring. The difference between is recorded as the first difference.

[0050] It should be noted that the difference represents the difference between two variables, which can be calculated by using difference, absolute value of difference, square of difference, ratio, etc., and the present embodiment does not limit the same.

[0051] When the first difference is large, it represents that the tension experienced during the stretching process breaks through more frequently. If the i-th position point still shows high deformation variable volatility under such frequent tension breakthrough, it represents that the i-th position point has high sensitivity to tension, and the greater the tension sensitivity; on the contrary, if the i-th position point does not have high deformation variable volatility, it represents that the i-th position point is insensitive to tension, and the smaller the tension sensitivity.

[0052] For the first deformation process of the spring, all position points of the spring are sorted according to the tension sensitivity from large to small, to obtain the arrangement order of each position point corresponding to each stretching, which is recorded as the deformation activation order of each position point. Position points with different tension sensitivities may have the characteristics of deformation activation order migration under the tension distribution of the cycle process in which they are located. Deformation activation order migration represents that the deformation resistance of the position point changes, and the subsequent sensitivity to tension increases.

[0053] ​For the initial tension value sequence in the primary cycle process, the same initial tension value is taken as a category, the ratio of the number of initial tension values in each category to the total number of initial tension values in the initial tension value sequence is calculated, and is recorded as the first ratio. For all the secondary stretching under each category of initial tension, the variance of the deformation activation sequence of each position point is calculated, which represents the influence of a category of initial tension on the migration of the deformation activation sequence of different position points.

[0054] Based on the above analysis, the deformation migration amount corresponding to the initial tension value sequence of the spring in each cycle is calculated, and the specific expression is:

[0055] In the formula, represents the first ratio of the nth initial tension in the current cycle, is the variance of the deformation activation sequence of the ith position point in the nth initial tension, recorded as the first dispersion, I is the number of position points on the spring, and P is the number of categories of initial tension in the initial tension value sequence in the current cycle, is the deformation migration amount corresponding to the initial tension value sequence of the spring in the current cycle.

[0056] The deformation migration amount represents the comprehensive influence degree of the gradual migration of each position point in the spring to the direction of increasing deformation sensitivity under the complex spring working condition characterized by random initial tension distribution in the current cycle.

[0057] The embodiment simulates high-frequency complex working conditions by applying random initial tension distribution to the spring, quantifies the deformation attenuation trend of the spring at the micro level under complex working conditions by tracking the migration change of the deformation activation sequence of different position points on the spring under each category of initial tension, and can more closely match the actual use scene of the spring and accurately track the micro change of the spring deformation force in the actual use scene compared with the traditional calculation of the deformation amount of the spring at the macro level.

[0058] S3, the stretching process of the spring is divided into a spiral uncoiling dominant segment and a mid-term loading segment, the change rate of the maximum tension of the spring stretched to the spiral uncoiling dominant segment in all the secondary stretching in the primary cycle is determined; the difference between the stress change trend in the spiral uncoiling dominant segment and the stress change trend in the mid-term loading segment in each stretching of the spring, and the stress change rate in the mid-term loading segment in each stretching are analyzed, and the stretching difficulty change rate of each stretching of the spring is determined.

[0059] After several cycles of testing of the spring, the spring elasticity attenuation gradually appears, when the spring is in the lower stress elasticity stage, the spring system will choose the most "energy-saving" deformation mode, that is, by rotating the spring coil angle to increase the pitch, rather than immediately causing the spring wire to bend and strain. This phenomenon is called "spiral uncoiling dominant period", which is a necessary stage of elastic deformation.

[0060] Therefore, the spring is divided into a spiral expansion dominant stage, a middle loading stage and a recovery stage in the process of force deformation. When the spring is in the spiral expansion dominant stage, stress is accumulated in the spring and the length is unchanged. When the spiral expansion dominant stage changes to the middle loading stage, the length of the spring changes and the force also changes. Therefore, according to the time point corresponding to the maximum change rate of the length in the length data of the spring, the stretching process of the spring is divided into the spiral expansion dominant stage and the middle loading stage.

[0061] With the spring in the continuous testing process, the change of the spring in different stages after the elasticity decreases may change. In the spiral expansion dominant stage of the spring, the spring deformation is small and the length is unchanged. With the decrease of the elasticity of the spring, the ability of the spring to store stress may decrease.

[0062] Based on this, in a stretching process of the spring, the embodiment obtains the maximum tension f of the spring in the spiral expansion dominant stage, which is recorded as the maximum tension. The maximum tension corresponding to all the stretching times in one cycle is obtained, and the maximum tension of all the stretching times is fitted by using the least square method to obtain a fitting curve q1, wherein the abscissa of the fitting curve q1 is the number of cycles, and the ordinate is the maximum tension. The least square method is a known technology, and the implementer can select other feasible curve fitting algorithms, which are not limited in the embodiment. It should be noted that the method of obtaining the fitting curve in the embodiment is the least square method.

[0063] The absolute value k1 of the average of the slopes of all the cycles in the fitting curve q1 is calculated, and the normalized value of the absolute value k1 is taken as the stress accumulation decay rate YD of the spring in the cycle, which reflects the change rate of the maximum tension. In the embodiment, the Sigmoid function is used to obtain the normalized value, and the implementer can select other feasible normalization methods, which are not limited in the embodiment.

[0064] With the decrease of spring elasticity, the storage stress capacity of the spiral uncoiling dominant section of the spring will decrease, resulting in the final stress of the spiral uncoiling dominant section being smaller and smaller. Since the spiral uncoiling dominant section spring stores less stress deformation and the length does not change, while the spring in the middle loading section deforms as a whole; the elastic deformation of the spring makes the force change on the spring slow; therefore, for a single stretching process of the spring, the fitting curve q2 of all force changes with time collected in the spiral uncoiling dominant section and the fitting curve q3 of all force changes with time collected in the middle loading section are obtained, the average slope k2 of all force positions collected in the fitting curve q2 is calculated, and the average slope k3 of all force positions collected in the fitting curve q3 is calculated, and the difference between the average slope k2 and the average slope k3 is recorded as a second difference, and the larger the second difference is, the more likely the spring is to be pulled apart after the transition from the spiral uncoiling dominant section to the middle loading section. The tension change diagram during the spring stretching process is shown in Figure 3 .

[0065] The first derivative function curve of the fitting curve q3 is obtained , the maximum function value in the first derivative function curve is counted, and the corresponding slope k4 at the maximum function value is calculated. The stretching difficulty change rate of the spring each time is calculated, and the expression is:

[0066] ; in the formula, is the stretching difficulty change rate of the spring u-th time, is the maximum function value corresponding to the spring u-th time, is the slope k4 corresponding to the maximum function value of the spring u-th time, is the average slope k2 of all force positions collected in the fitting curve q2 of the u-th time, is the average slope k3 of all force positions collected in the fitting curve q3 of the u-th time, is the second difference, and is recorded as the first product.

[0067] It should be understood that when the second difference is smaller, it indicates that the stretching difficulty of the spring in the middle loading section is higher at this time, and the first product is larger at this time, indicating that the slope of the stress curve in the middle loading section is large and the slope decreases quickly, and therefore the stretching difficulty change rate of the middle loading section is larger.

[0068] S4, the change trend of the stretching difficulty change rate in all sub-stretching of a cycle is analyzed, and the change rate of the maximum tension is combined to obtain the elasticity measure corresponding to the initial tension value sequence of the spring each cycle.

[0069] The spring in a force cycle, when the initial tension of the spring is smaller, the stretching length change rate of the spring is slower, when the spring is better in elasticity, the spring needs to break through more elastic resistance, that is, the stretching difficulty will change many times; therefore, the initial tension of the spring in a cycle is arranged in descending order, and the fitting curve q4 of the stretching difficulty change rate of all the stretching in the current arrangement is obtained. The abscissa in the fitting curve q4 is the serial number of the initial tension arranged in descending order, and the ordinate is the stretching difficulty change rate.

[0070] The average slope absolute value of all the stretching corresponding positions in the fitting curve q4 is calculated, based on which, the elasticity measure corresponding to the initial tension value sequence of the spring per cycle is determined, and the expression is:

[0071] ; in the formula, is the elasticity measure of the spring in the current cycle, is the stress accumulation decay rate of the spring in the current cycle, j is the average value of the stretching difficulty change rate of all the stretching in the current cycle of the spring, is the average slope absolute value of all the stretching corresponding positions in the fitting curve q4 of the spring in the current cycle, exp() is the exponential function with natural constant as the base. The is recorded as the second product.

[0072] It should be understood that the larger the second product is, the greater the stretching change rate of the spring in the current cycle is, and the greater the stretching difficulty of the spring is as the initial tension gradually decreases, and the smaller the stress accumulation decay rate is, indicating that the stress decay of the spring is lower, and the elasticity of the spring is greater.

[0073] S5, based on the time point difference between the deformation migration amount and the elasticity measure in the process of all the cycles of the spring collapse, and combining the complete collapse time of the spring, the deformation collapse coefficient of the spring is obtained, and the deformation collapse of the same batch of springs produced is detected.

[0074] The fitting curve q5 of the elasticity measure of all the cycles in the whole test process of the spring is obtained, and the fitting curve q6 of the deformation migration amount of all the cycles is obtained, wherein the abscissa in the fitting curve q5 and the fitting curve q6 is the time point corresponding to each cycle, the ordinate in the fitting curve q5 is the elasticity measure, and the ordinate in the fitting curve q6 is the deformation migration amount.

[0075] The deformation of the spring becomes more and more obvious during the spring test process, and the elasticity of the spring becomes lower and lower. Since the service life of the spring is not the complete collapse of the spring, when the spring is deformed to a certain extent and the elasticity of the spring is reduced to a certain extent, the performance of the spring cannot meet the use requirement. Therefore, the embodiment obtains a time point t2 corresponding to the maximum value in the derivative curve of the fitting curve q5 and a time point t1 corresponding to the maximum value in the derivative curve of the fitting curve q6, obtains a time point t3 closest to the time point t1 and the time point t2, and takes the time point t3 as the deformation collapse point of the spring.

[0076] A normalized value of a ratio of a time length corresponding to the deformation collapse point of the spring to a complete collapse time length of the spring is taken as a deformation collapse coefficient of the spring. The deformation collapse coefficient of the spring is obtained by comparing the obtained deformation collapse time point of the spring with the complete deformation collapse time of the spring; since the service life of the spring is not consumed when the spring is completely collapsed and broken, the actual deformation collapse coefficient is obtained by analyzing the performance attenuation of the spring.

[0077] It should be understood that the larger the deformation collapse coefficient of the spring is, the later the deformation collapse point of the spring occurs, and the better the production quality of the spring is. Therefore, the embodiment sets a threshold value, and if the deformation collapse coefficients of the extracted springs are all less than the preset threshold value, it is determined that the quality of the same batch of springs produced is unqualified and is more prone to deformation collapse risk, otherwise, it is determined that the quality of the same batch of springs produced is qualified. The preset threshold value in the embodiment is 0.6, and the implementer can set it according to the actual situation, which is not limited in the embodiment.

[0078] Based on the same inventive concept as the above method, the embodiment of the present application also provides a spring deformation collapse detection device, the device stores a computer program, and the computer program is executed by the processor to realize any one of the above spring deformation collapse detection methods.

[0079] Based on the same inventive concept as the above method, the embodiment of the present application also provides a spring deformation collapse detection system, which includes a memory, a processor and a computer program stored in the memory and running on the processor, and the processor executes the computer program to realize the steps of any one of the above spring deformation collapse detection methods.

[0080] It should be noted that the above sequence of the embodiments of the present application is only for description, and does not represent the advantages and disadvantages of the embodiments. The above describes specific embodiments of the present application. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multi-task processing and parallel processing are also possible or can be advantageous.

[0081] The various embodiments in the specification are described in progressive manner, and the same or similar parts between the various embodiments can be mutually referred to, and each embodiment focuses on the difference from other embodiments.

[0082] The above only describes the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the principles of the present application shall be included in the protection scope of the present application.

Claims

1. A spring deformation collapse detection method, characterized by, The method comprises the following steps: In the same batch of springs produced, a plurality of springs are randomly selected for deformation and collapse detection, a sequence of initial tension values is randomly set in the tension bearing range of the spring, each initial tension value in the sequence of initial tension values is used to stretch the spring to a fixed length, then the force is released to make it rebound to a free state, and the process is repeated until the spring completely collapses; By the change of the deformation amount of each position point on the spring during the test process and the difference between the tension when stretched to the fixed length and the initial tension value, the tension sensitivity of each position point of the spring during each stretching is determined; based on the change degree of the tension sensitivity of each position point on the spring in one cycle, and in combination with the distribution of each initial tension value in the sequence of initial tension values, the deformation migration amount corresponding to the sequence of initial tension values for each cycle of the spring is determined; The difference in the force change trend at different stages in each stretching of the spring, and the stretching difficulty change rate of each stretching of the spring are determined by analyzing the force change rate of the spring during stretching; The change trend of the stretching difficulty change rate in all the stretchings in one cycle is analyzed, and the elasticity measure corresponding to the sequence of initial tension values for each cycle of the spring is obtained in combination with the change rate of the tension of the spring during stretching; Based on the time point difference between the change trend of the deformation migration amount and the elasticity measure, and in combination with the complete collapse time of the spring, the deformation and collapse coefficient of the spring is obtained, and the deformation and collapse detection of the same batch of springs produced is performed; The determination of the tension sensitivity of each position point of the spring during each stretching comprises: The dispersion degree of the deformation amount per unit time of each position point on the spring during stretching and rebounding is determined, the difference between the tension when the spring is stretched to the fixed length and the initial tension value is recorded as a first difference, and the tension sensitivity is a ratio of the dispersion degree and the first difference; The determination of the deformation migration amount corresponding to the sequence of initial tension values for each cycle of the spring comprises: For each stretching of the spring, all the position points are arranged in descending order of tension sensitivity to obtain the arrangement position sequence corresponding to each position point in each stretching; The same initial tension value in the sequence of initial tension values is taken as a category, the ratio of the number of initial tension values in each category of initial tension values to the total number of initial tension values in the sequence of initial tension values is calculated and recorded as a first ratio, for one cycle of the sequence of initial tension values, the dispersion degree of the arrangement position sequence corresponding to each position point of the spring in all the stretchings of each category of initial tension values is calculated and recorded as a first dispersion degree; The product of the first ratio and the first dispersion degree is calculated, and the average value of the product of all the position points of the spring for all the categories of initial tension values corresponding to one cycle of the sequence of initial tension values is taken as the deformation migration amount corresponding to one cycle of the sequence of initial tension values; The determination of the stretching difficulty change rate of each stretching of the spring comprises: The stretching process of the spring is divided into a spiral expansion dominant segment and a middle loading segment, the force fitting curves of the spring during each stretching in the spiral expansion dominant segment and the middle loading segment are determined respectively, the difference between the average slopes of all the force positions collected in the force fitting curves of the spiral expansion dominant segment and the middle loading segment is calculated and recorded as a second difference; When the spring is in the spiral expansion dominant stage, stress is accumulated in the spring and the length of the spring is constant, and when the spiral expansion dominant stage changes to the medium loading stage, the length and stress of the spring change; A derivative curve of a fitting curve of the time-varying stress of the medium loading stage is determined, a product of a maximum function value of the derivative curve and a slope corresponding to the maximum function value is calculated, and the product is denoted as a first product, and the stretching difficulty change rate is a ratio of the first product to the second difference; The elastic metric corresponding to the sequence of initial tension values of the spring per cycle is obtained by: An average slope absolute value of a fitting curve of the stretching difficulty change rate in all the sub-stretchings corresponding to the sequence of initial tension values of the spring per cycle is determined, and an average value of the stretching difficulty change rate is determined, wherein the abscissa of the fitting curve of the stretching difficulty change rate is the sequence number of the initial tension arranged from large to small; A product of the average slope absolute value and the average value is calculated, and the product is denoted as a second product, a change rate of the maximum tension of the spring stretched to the spiral expansion dominant stage in all the sub-stretchings is determined, a reciprocal of a ratio of the change rate of the maximum tension to the second product is calculated, the reciprocal is taken as an index of an exponential function with a natural constant as a base number, and a calculation result of the exponential function is taken as the elastic metric corresponding to the sequence of initial tension values of the spring per cycle. The deformation collapse coefficient of the spring is obtained by: A time point t1 corresponding to a maximum value in a derivative curve of a fitting curve of the deformation migration amount of the spring in all the sub-cycles is determined, a time point t2 corresponding to a maximum value in a derivative curve of a fitting curve of the elastic metric of the spring in all the sub-cycles is determined, a time point t3 closest to the time point t1 and the time point t2 is obtained, and the time point t3 is taken as a deformation collapse point of the spring; A normalized value of a ratio of a time length corresponding to the deformation collapse point of the spring to a complete collapse time length of the spring is calculated as the deformation collapse coefficient of the spring.

2. A spring set-up collapse detection method as claimed in claim 1, wherein, The deformation collapse detection on the same batch of springs produced is performed by: if the deformation collapse coefficients of the extracted springs are all less than a preset threshold value, it is determined that the same batch of springs produced is unqualified and is more prone to deformation collapse risk, otherwise, it is determined that the same batch of springs produced is qualified.

3. A spring deformation collapse detection apparatus, said apparatus having stored therein a computer program, characterized in that, The computer program is executed by the processor to implement a spring deformation collapse detection method according to any one of claims 1-2.

4. A spring deformation collapse detection system comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, The processor executes the computer program to implement the steps of the method according to any one of claims 1-2.

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