Non-uniform load distribution ball screw shoulder climbing performance detection method

Abstract

The invention discloses a non-uniform load distribution ball screw shoulder climbing performance detection method, and relates to the field of mechanical component performance detection.The non-uniform load distribution ball screw shoulder climbing performance detection method comprises the steps that on the basis of structure parameters, material parameters and working condition parameters of a ball screw, the performance of the ball screw is detected; determining a uniform load coefficient of the ball screw under the structure parameters, the material parameters and the working condition parameters; based on the structure parameters, the material parameters and the working condition parameters, the limit contact angle of the lead screw is obtained; and based on the limit contact angle of the screw, through a preset shoulder climbing calculation model, obtaining a climbing rate of a ball of the ball screw under an unbalance loading condition, and based on the climbing rate and design requirements, determining a detection result of the shoulder climbing performance of the ball screw. According to the method, the non-uniform load distribution is considered, so that the shoulder climbing performance of the ball screw can be detected and evaluated more accurately.

Description

Technical Field

[0001] The present application relates to the technical field of mechanical component performance detection, and in particular to a method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution. Background Art

[0002] In mechanical systems, ball screws are a key transmission component, and their performance directly affects the operating efficiency and reliability of the entire system. The performance test of ball screws is particularly important because they are often affected by non-uniform load distribution, processing errors, and installation deviations in actual use. These factors may cause the ball screw to have shoulder creep, thus affecting its working accuracy and life. Therefore, accurately evaluating the performance of ball screws under actual working conditions, especially their shoulder creep characteristics, is a key requirement for improving the overall performance and reliability of mechanical systems.

[0003] At present, the shoulder creep performance of ball screws is mainly evaluated by the relevant national standards for rolling bearings, and the load distribution between balls is handled by calculation models based on finite element analysis and experimental data. These methods usually assume that all balls are loaded evenly and are mainly based on traditional load distribution calculation methods, such as the research results of Nanjing University of Science and Technology. These existing methods can predict the performance of ball screws to a certain extent, but they fail to fully consider the non-uniform load distribution under actual working conditions, which may lead to inaccurate performance predictions.

[0004] There are usually some problems with the existing ball screw performance testing methods. For example, the influence of eccentric load is not considered. The current calculation model usually assumes that the ball is evenly loaded, but ignores the non-uniform load distribution that may exist in actual work. This causes the calculated climbing rate to be lower than the actual situation, affecting the accuracy of the test results. The eccentric load coefficient is irrelevant to the calculation of the shoulder climbing performance. The existing eccentric load coefficient calculation method fails to be associated with the calculation model of the shoulder climbing performance, and cannot effectively analyze the actual impact of the eccentric load characteristics on the performance of the ball screw. The existing technology has not yet proposed a calculation model for the shoulder climbing performance of the ball screw that comprehensively considers the non-uniform load distribution, and cannot fully reflect the impact of the load distribution on the performance. Therefore, accurately detecting the shoulder climbing performance of the ball screw under the condition of non-uniform load distribution has become an urgent problem to be solved. Summary of the invention

[0005] The purpose of this application is to provide a method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution, aiming to solve the problem of how to accurately detect the shoulder climbing performance of a ball screw under non-uniform load distribution conditions.

[0006] To achieve the above objectives, the present application proposes a method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution, the method comprising:

[0007] Based on the structural parameters, material parameters and operating parameters of the ball screw, determining the load sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters;

[0008] Based on the structural parameters, material parameters and working condition parameters, a limit contact angle of the lead screw is obtained;

[0009] Based on the limit contact angle of the screw, the climbing rate of the ball of the ball screw under the eccentric load condition is obtained by presetting the shoulder climbing calculation model. Based on the climbing rate and design requirements, the test result of the shoulder climbing performance of the ball screw is determined.

[0010] In one embodiment, based on the structural parameters, material parameters and operating parameters of the ball screw, determining the load sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters includes:

[0011] Based on the normal force on a single ball and the semi-minor axis length of the Hertzian contact length, the maximum contact stress of a single ball under uniform load conditions is obtained;

[0012] Based on the Hertz contact elastic deformation coefficient, the principal curvatures of the ball and the lead screw and the material parameters, the elastic deformation coefficient of the contact point between the ball and the lead screw is obtained;

[0013] Based on the maximum contact stress, the principal curvature and the Hertzian contact length coefficient of the minor and semi-minor axes, and the material parameters, a critical normal load for generating plastic deformation is obtained;

[0014] When the normal force borne by the ball is greater than the critical normal load, the plastic deformation coefficient between the ball and the screw is obtained based on the elastic deformation coefficient of the Hertzian contact, the maximum elastic deformation, the material parameters and the sum of the principal curvatures;

[0015] The load sharing coefficient is obtained based on the elastic deformation coefficient of the contact point between the ball and the screw, the plastic deformation coefficient between the ball and the screw, the structural parameters and the operating parameters.

[0016] In one embodiment, the load sharing coefficient is obtained based on the elastic deformation coefficient of the contact point between the ball and the screw, the plastic deformation coefficient between the ball and the screw, the structural parameters and the working condition parameters, including:

[0017] Based on the normal force and structural parameters borne by the single ball, a correction coefficient based on finite element and experimental results is introduced to obtain the axial strain of the nut and the screw and the constant term of the coordination equation;

[0018] Based on the constant term of the coordination equation, the normal force on the ball, the working condition parameters, the elastic deformation coefficient and the plastic deformation coefficient of the contact point between the ball and the screw, a group of algebraic equations of the normal load of all the balls is established;

[0019] Based on the normal load algebraic equations, the influence of contact angle and axial load on eccentric load is obtained;

[0020] With reference to the influence of contact angle and axial load on eccentric load, the load sharing factor is obtained based on the average normal load and the maximum normal load.

[0021] In one embodiment, based on the structural parameters, material parameters and operating parameters of the ball screw, before determining the load sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters, the method further includes:

[0022] Based on the working condition parameters and structural parameters, the normal force borne by a single ball and the principal curvature of the Hertzian contact are obtained;

[0023] Based on the principal curvature of the Hertzian contact, the first kind of elliptic integral, the second kind of elliptic integral and the equivalent radius of the Hertzian contact in each direction are obtained;

[0024] Based on the second kind of elliptic integral and the equivalent radius of the Hertzian contact in each direction, the length coefficient of the long and short semi-axis of the Hertzian contact is obtained;

[0025] Based on the first kind of elliptic integral, the second kind of elliptic integral and the equivalent radius of the Hertzian contact in each direction, the elastic deformation coefficient of the Hertzian contact is obtained;

[0026] The major and minor semi-axis lengths of the Hertzian contact are obtained based on the principal curvature of the Hertzian contact, the operating parameters, the material parameters, the major and minor semi-axis length coefficients of the Hertzian contact, and the elastic deformation coefficient of the Hertzian contact.

[0027] In one embodiment, based on the structural parameters, material parameters and working condition parameters, obtaining the limit contact angle of the screw includes:

[0028] Based on the structural parameters, the angle between the line connecting the center of curvature of the nut groove and the edge of the shoulder and the center line of the outer ring groove is calculated;

[0029] Based on the angle between the line connecting the center of curvature of the nut channel and the edge of the shoulder and the center line of the outer ring channel, the structural parameters, the operating parameters, the material parameters, the length of the major and minor semi-axis of the Hertzian contact, and the sum of the principal curvatures, the limiting contact angle of the screw is obtained.

[0030] In one embodiment, based on the limit contact angle of the screw, a preset shoulder climbing calculation model is used to obtain the climbing rate of the ball of the ball screw under the eccentric load condition, and based on the climbing rate and design requirements, the test result of the shoulder climbing performance of the ball screw is determined, including:

[0031] Based on the limit contact angle and the structural parameters, the maximum allowable axial load of the ball screw is obtained;

[0032] Based on the maximum allowable axial load when the load is evenly distributed and the load-distributing factor, a maximum allowable axial load when the load is unevenly distributed is obtained;

[0033] Based on the limit contact angle, the structural parameters and the operating condition parameters, a maximum load-averaged allowable design contact angle is obtained;

[0034] Based on the limit contact angle, the load-balancing coefficient, the structural parameters and the operating parameters, a maximum eccentric load allowable design contact angle is obtained;

[0035] When at least one of the following conditions is met: the actual axial load is greater than the maximum allowable axial load under even load, the actual axial load is greater than the maximum allowable axial load under eccentric load, the actual contact angle is greater than the maximum allowable design contact angle under even load, and the actual contact angle is greater than the maximum allowable design contact angle under eccentric load, it is determined that shoulder creep has occurred in the ball screw.

[0036] In one embodiment, based on the limit contact angle of the screw, the climbing rate of the ball of the ball screw under the eccentric load condition is obtained by presetting the shoulder climbing calculation model, including:

[0037] Based on the load-balancing coefficient, the structural parameters and the actual working conditions, an actual eccentric load contact angle is obtained;

[0038] Based on the actual eccentric load contact angle and the limit contact angle, the creep rate of the ball screw under eccentric load conditions is obtained.

[0039] In addition, to achieve the above purpose, the present application also proposes a ball screw shoulder climbing performance detection device with non-uniform load distribution, the device comprising:

[0040] A calculation module, for determining a load-sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters of the ball screw based on the structural parameters, material parameters and operating parameters of the ball screw;

[0041] An acquisition module, used for acquiring a limit contact angle of the lead screw based on the structural parameters, material parameters and working condition parameters;

[0042] A module is obtained, which is used to obtain the climbing rate of the ball of the ball screw under eccentric load conditions based on the limit contact angle of the screw and through a preset shoulder climbing calculation model, and to determine the ball screw shoulder climbing performance test result based on the climbing rate and design requirements.

[0043] In addition, to achieve the above-mentioned objectives, the present application also proposes a device for detecting the climbing performance of a ball screw shoulder with non-uniform load distribution, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the method for detecting the climbing performance of a ball screw shoulder with non-uniform load distribution as described above.

[0044] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by the processor, the steps of the ball screw shoulder climbing performance detection method with non-uniform load distribution are implemented as described above.

[0045] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, it implements the steps of the ball screw shoulder climbing performance detection method with non-uniform load distribution as described above.

[0046] One or more technical solutions proposed in this application have at least the following technical effects:

[0047] Based on the structural parameters, material parameters and operating parameters of the ball screw, the load-sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters is determined; based on the structural parameters, material parameters and operating parameters, the limit contact angle of the screw is obtained; based on the limit contact angle of the screw, the climbing rate of the ball of the ball screw under the eccentric load condition is obtained by using a preset shoulder climbing calculation model, and the test result of the shoulder climbing performance of the ball screw is determined based on the climbing rate and design requirements. This application determines the load-sharing coefficient of the ball screw by comprehensively considering the structural parameters, material parameters and operating parameters of the ball screw, obtains the limit contact angle of the screw, and uses a preset shoulder climbing calculation model to obtain the climbing rate of the ball screw under the eccentric load condition. It can accurately detect and analyze the shoulder climbing performance of the ball screw under non-uniform load distribution conditions, and realizes effective detection and evaluation of the key performance of the ball screw. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0049] 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 the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0050] Figure 1 A flow chart of a first embodiment of a method for detecting the climbing performance of a ball screw shoulder with non-uniform load distribution provided in the present application;

[0051] Figure 2 A flow chart of the second embodiment of the ball screw shoulder climbing performance detection method with non-uniform load distribution provided in the present application;

[0052] Figure 3 A schematic diagram of a brief process of a method for detecting the climbing performance of a ball screw shoulder with non-uniform load distribution in this application;

[0053] Figure 4 This is a schematic diagram of the module structure of a ball screw shoulder climbing performance detection device with non-uniform load distribution according to an embodiment of the present application;

[0054] Figure 5 Schematic diagram of the equipment structure of the hardware operating environment involved in the method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution in an embodiment of the present application.

[0055] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0056] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0057] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0058] At present, the shoulder creep performance evaluation of ball screws mainly relies on the national standard of rolling bearings, and the load distribution between balls is processed through finite element analysis and experimental data models. These methods usually assume that the balls are loaded evenly and use traditional load distribution calculation methods, such as the research results of Nanjing University of Science and Technology. Although these methods can predict the performance of ball screws to a certain extent, they do not fully consider the non-uniform load distribution under actual working conditions, which may lead to inaccurate predictions.

[0059] The main solution of the embodiment of the present application is: comprehensively consider the structural parameters, material parameters and operating parameters of the ball screw, determine the load-sharing coefficient of the ball screw, and obtain the limit contact angle of the screw based on these parameters, and use the determined load-sharing coefficient, limit contact angle and preset shoulder climbing calculation model to obtain the creep rate and other relevant design requirements of the ball screw under eccentric load conditions, standardize the parameter range of the actual working conditions based on the relevant design requirements, and accurately detect and analyze the shoulder climbing performance of the ball screw under non-uniform load distribution conditions based on the creep rate, thereby achieving effective detection and evaluation of the key performance of the ball screw.

[0060] It should be noted that the execution subject of the embodiment of the present application can be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an electronic device capable of realizing the above functions, etc. The following takes a computer as an example to illustrate this embodiment and the following embodiments.

[0061] Based on this, the embodiment of the present application provides a method for detecting the climbing performance of a ball screw shoulder with non-uniform load distribution, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the ball screw shoulder climbing performance detection method with non-uniform load distribution of the present application.

[0062] In this embodiment, the method for detecting the climbing performance of a ball screw shoulder with non-uniform load distribution includes steps S10 to S30:

[0063] Step S10, based on the structural parameters, material parameters and operating parameters of the ball screw, determining the load sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters;

[0064] It should be noted that structural parameters refer to parameters related to the structural design of ball screws. These parameters include but are not limited to the screw pitch, lead, nut outer diameter, ball diameter, number of balls, raceway shape and angle, raceway curvature radius and ball radius ratio, number of ball turns, etc. Material parameters refer to the physical and mechanical performance parameters of the materials used for ball screws and their components. These parameters include but are not limited to the elastic modulus, yield strength, Poisson's ratio of raceways and balls, density, hardness, fatigue strength, etc. of the material. Working condition parameters refer to the various working conditions to which the ball screw is subjected in the actual working environment. These conditions include but are not limited to axial loads, etc. The load-balancing coefficient refers to a quantitative indicator of the uniformity of the load on each ball during the entire working process of the ball screw. It is used to measure whether the load distribution between balls is uniform. The closer the value is to 1, the more uniform the load distribution is, and the more the value deviates from 1, the more uneven the load distribution is. The load-balancing coefficient is an important parameter in the performance evaluation of ball screws, which directly affects their service life and operating stability.

[0065] It is understood that by comprehensively considering these structural parameters, material parameters and operating parameters, the load distribution factor of the ball screw under actual working conditions can be determined more accurately. The load distribution factor is an important performance indicator that reflects the ability of the ball screw to evenly distribute the load under various conditions. The process of determining the load distribution factor usually involves complex calculations and simulation analysis to ensure that the ball screw has good load distribution characteristics in actual applications, thereby improving its performance and service life.

[0066] As an example, based on the structural parameters, material parameters and operating parameters of the ball screw, before determining the load-sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters, it also includes: based on the operating parameters and structural parameters, obtaining the normal force borne by a single ball and the principal curvature of the Hertzian contact; based on the principal curvature of the Hertzian contact, obtaining the first kind of elliptic integral, the second kind of elliptic integral and the equivalent radius in each direction of the Hertzian contact; based on the second kind of elliptic integral and the equivalent radius in each direction of the Hertzian contact, obtaining the major and minor axis length coefficient of the Hertzian contact; based on the first kind of elliptic integral, the second kind of elliptic integral and the equivalent radius in each direction of the Hertzian contact, obtaining the elastic deformation coefficient of the Hertzian contact; based on the principal curvature of the Hertzian contact, the operating parameters, material parameters, the major and minor axis length coefficient of the Hertzian contact and the elastic deformation coefficient of the Hertzian contact, obtaining the major and minor axis lengths of the Hertzian contact.

[0067] The normal force on a single ball refers to the force perpendicular to the contact surface on each ball in the ball screw. This force is generated by the action of the ball between the nut and the screw. The calculation formula is:

[0068]

[0069] Among them, P n is the normal force on a single ball, z is the total number of working balls, α is the contact angle, F α is the axial external load, and λ is the helix angle. The principal curvature of the Hertzian contact refers to the curvature of the contact area along the two main directions at the contact point. In the ball screw system, these principal curvatures are the curvatures of the contact surfaces of the ball and the screw at the contact point. The principal curvature determines the geometric characteristics of the contact point and is an important parameter for calculating contact stress and deformation. The calculation formula is:

[0070]

[0071] Among them, ρ 11 , ρ 12 , ρ 21 , ρ 22 are the principal curvatures of the ball on the principal plane 1 and the principal plane 2, and the principal curvatures of the screw on the principal plane 1 and the principal plane 2, respectively. b is the ball diameter, d0 is the nominal diameter of the screw, and t is the ratio of the raceway curvature radius to the ball radius. The first kind of elliptic integral is usually expressed as K(k). In Hertz contact theory, it is related to the stress distribution and deformation in the contact area. The second kind of elliptic integral is usually expressed as E(k). In Hertz contact theory, it is also related to the stress distribution and deformation in the contact area, especially when calculating the major and minor semi-axis lengths of the contact area. The equivalent radius in each direction of Hertz contact refers to the equivalent curvature radius of the contact area in the two main directions. They reflect the geometric characteristics of the contact area and are very important for calculating contact stress and deformation. Their calculation formulas are:

[0072]

[0073] Among them, Rx and Ry refer to the equivalent radii in two different directions of Hertzian contact respectively. E is the elliptic integral of the first kind, and F is the elliptic integral of the second kind. The major and minor semi-axis length coefficients of Hertzian contact are calculated according to the Hertzian contact theory through elliptic integrals and equivalent radii. They are used to determine the major and minor semi-axis lengths of the contact area. Hertzian contact elastic deformation coefficient This is a coefficient that describes the elastic deformation of the ball and screw in the contact area. It is based on the Hertzian contact theory and reflects the elastic deformation characteristics of the contact surface when subjected to force. The major and minor semi-axis lengths of Hertzian contact refer to the major and minor semi-axis lengths of the contact area at the contact point, reflecting the geometric dimensions of the contact area. Among them, their calculation formulas are:

[0074]

[0075] Among them, k is the intermediate coefficient for calculating the following three formulas, a* is the major semi-axis length coefficient of the Hertzian contact, b* is the minor semi-axis length coefficient of the Hertzian contact, and δ* is the elastic deformation coefficient of the Hertzian contact.

[0076] In this example, based on the operating parameters and structural parameters, the normal force on a single ball and the principal curvature of the Hertz contact are first calculated. Next, the principal curvature is used to calculate the first-kind elliptic integral, the second-kind elliptic integral and the equivalent radius of the Hertz contact in each direction. Then, the long and short semi-axis length coefficients of the Hertz contact are determined by the second-kind elliptic integral and the equivalent radius. The elastic deformation coefficient of the Hertz contact is calculated by combining the first and second-kind elliptic integrals and the equivalent radius. Finally, based on the principal curvature, operating parameters, material parameters, the long and short semi-axis length coefficients of the Hertz contact and the elastic deformation coefficient, the long and short semi-axis lengths of the Hertz contact area are obtained. In this way, the force and deformation characteristics of the contact area between the ball and the screw can be accurately described, thereby providing a reliable basis for subsequent stress analysis and design optimization.

[0077] As an example, based on the structural parameters, material parameters and operating parameters of the ball screw, the load-sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters is determined, including: based on the normal force borne by a single ball and the Hertzian contact length and short-semi-axis length, the maximum contact stress of a single ball under load-sharing conditions is obtained; based on the Hertzian contact elastic deformation coefficient, the sum of the principal curvatures of the ball and the screw, and the material parameters, the elastic deformation coefficient of the contact point between the ball and the screw is obtained; based on the maximum contact stress, the sum of the principal curvatures, the Hertzian contact length and short-semi-axis length coefficient and the material parameters, the critical normal load for plastic deformation is obtained; when the normal force borne by the ball is greater than the critical normal load, based on the Hertzian contact elastic deformation coefficient, the maximum elastic deformation, the material parameters and the sum of the principal curvatures, the plastic deformation coefficient between the ball and the screw is obtained; based on the elastic deformation coefficient of the contact point between the ball and the screw, the plastic deformation coefficient between the ball and the screw, the structural parameters and the operating parameters, the load-sharing coefficient is obtained.

[0078] Among them, the semi-long and semi-short axis lengths of Hertz contact are in the Hertz contact theory. When two surfaces are in contact, the contact area is usually elliptical. The semi-long and semi-short axis lengths refer to the lengths of the major and minor axes of the elliptical contact area. Their calculation formulas are:

[0079]

[0080] Where a and b are the lengths of the major and minor semi-axes of the Hertzian contact, ∑ρ is the sum of the principal curvatures, E1 and E2 are the elastic moduli of the ball and raceway, and μ1 and μ2 are the Poisson's ratios of the ball and raceway. The maximum contact stress refers to the maximum stress value in the contact area between the ball and the screw under uniform load conditions. This is an important indicator that determines the strength and durability of the contact surface when subjected to load. Its calculation formula is:

[0081]

[0082] Among them, σm is the maximum contact stress. The elastic deformation coefficient of the contact point between the ball and the screw is a coefficient calculated based on the Hertz contact theory, which describes the elastic deformation of the ball and the screw at the contact point due to the normal force. After the critical normal load value of plastic deformation exceeds this normal load, the load value at which plastic deformation begins to occur in the contact area between the ball and the screw. Below this load, only elastic deformation occurs in the contact area. The maximum elastic deformation is the maximum elastic deformation that occurs when the contact point between the ball and the screw is subjected to the maximum normal force. This is the maximum deformation value of the ball and the screw without plastic deformation. Their calculation formulas are:

[0083]

[0084]

[0085] Among them, σs refers to the yield strength, K1 refers to the elastic deformation coefficient of the contact point between the ball and the screw, A is the intermediate coefficient when calculating the plastic deformation coefficient, K2 refers to the plastic deformation coefficient, δ y The plastic deformation coefficient between the ball and the screw describes the degree of plastic deformation in the contact area between the ball and the screw when the normal force exceeds the critical load.

[0086] The maximum contact stress of a single ball under normal force is calculated by considering the normal force on the ball and the semi-long and short axis length of the Hertzian contact. Under uniform load conditions, this maximum contact stress reflects the maximum stress in the contact area between the ball and the screw. Next, the elastic deformation coefficient of the contact point between the ball and the screw is determined using the elastic deformation coefficient of the Hertzian contact theory, as well as the principal curvatures and material parameters of the ball and the screw. This coefficient describes the degree of deformation of the ball and the screw when elastic deformation occurs at the contact point. Then, based on the maximum contact stress, principal curvature, semi-long and short axis length coefficient of the Hertzian contact, and material parameters calculated previously, the critical normal load for plastic deformation is calculated. This critical normal load refers to the value above which the normal force exceeds which the contact point between the ball and the screw will begin to undergo irreversible plastic deformation. In the case where the normal force on the ball is greater than the above critical normal load, it is necessary to further calculate the plastic deformation coefficient between the ball and the screw. This step is based on the elastic deformation coefficient of the Hertzian contact, the maximum elastic deformation, the material parameters, and the principal curvatures. The plastic deformation coefficient describes the degree of deformation when the ball and the screw are plastically deformed at the contact point. Finally, the load-sharing coefficient of the ball screw is calculated by combining the elastic deformation coefficient and plastic deformation coefficient of the contact point between the ball and the screw obtained above, as well as the structural parameters and operating parameters of the ball screw. The load-sharing coefficient reflects the uniformity of the load distribution of the ball in the ball screw system, which is of great significance for evaluating the performance and reliability of the system.

[0087] Step S20, obtaining a limit contact angle of the lead screw based on the structural parameters, material parameters and working condition parameters;

[0088] It should be noted that in a ball screw system, the limiting contact angle refers to the maximum contact angle formed between the ball and the screw raceway. This angle is determined by the geometric design, material properties and working conditions of the ball screw, and is usually used to evaluate the contact conditions and stress distribution of the ball screw under different loads and working conditions. Specifically, the limiting contact angle refers to the maximum value of the contact angle between the ball and the raceway surface under maximum load or extreme working conditions. When the ball screw is subjected to a large load, the contact area between the ball and the raceway will deform and the contact angle will change accordingly. The determination of the limiting contact angle can help analyze the contact behavior and load distribution of the ball and raceway under maximum stress conditions.

[0089] It is understandable that in this step, by comprehensively considering the structural parameters of the ball screw, such as thread angle, lead, ball diameter, etc., material parameters, such as the elastic modulus of the ball and screw materials, etc., and actual working conditions, such as axial load, etc., the maximum contact angle formed between the ball and the screw raceway under extreme working conditions, that is, the limit contact angle, is calculated and determined. This process includes analyzing the contact behavior between the ball and the raceway under different loads and working conditions, and evaluating its deformation and stress distribution under maximum stress conditions. By obtaining the limit contact angle, the performance of the ball screw under load can be more accurately predicted to ensure its reliability and service life.

[0090] As an example, based on the structural parameters, material parameters and operating parameters, the limiting contact angle of the screw is obtained, including: based on the structural parameters, calculating the angle between the line connecting the center of curvature of the nut channel and the edge of the shoulder and the center line of the outer ring channel; based on the angle between the line connecting the center of curvature of the nut channel and the edge of the shoulder and the center line of the outer ring channel, the structural parameters, the operating parameters, the material parameters, the length of the major and minor semi-axis of Hertzian contact, and the sum of the principal curvatures, obtaining the limiting contact angle of the screw.

[0091] Among them, the angle between the line connecting the center of curvature of the nut channel and the edge of the shoulder and the center line of the outer ring channel refers to the angle between the straight line from the center of curvature of the nut channel (i.e. the geometric center of the channel) to the edge of the shoulder of the nut and the center line of the outer ring channel of the nut. This angle reflects the relationship between the geometric shape of the nut and the assembly structure, and has an important influence on the stress distribution and contact conditions. The limit contact angle refers to the maximum contact angle that can be maintained between the ball and the screw under specific working conditions and structural parameters. At this angle, the contact stress and deformation reach a critical state, and increasing the contact angle will cause the contact surface to no longer be able to withstand greater loads or deformations. This is an important parameter when designing and analyzing ball screw pairs, which directly affects their load-bearing capacity and life.

[0092] Based on the structural parameters, the angle between the line connecting the center of curvature of the nut channel and the edge of the shoulder and the center line of the outer ring channel is first calculated, which is an important step in determining the geometric structure of the nut. Then, the limiting contact angle of the screw is calculated using this angle, the structural parameters, operating parameters, material parameters of the nut and the screw, and the length of the major and minor semi-axis and the sum of the main curvatures obtained through the Hertz contact analysis. The limiting contact angle represents the maximum contact angle that can be tolerated between the ball and the screw under specific conditions. This is an important parameter for evaluating contact stress and deformation, and helps to ensure the stability and performance of the system under high loads. Through these steps, the contact characteristics and mechanical properties of the screw system can be fully analyzed and optimized, thereby improving its reliability and service life.

[0093] Step S30, based on the limit contact angle of the screw, through the preset shoulder climbing calculation model, the climbing rate of the ball of the ball screw under the eccentric load condition is obtained, and based on the climbing rate and design requirements, the ball screw shoulder climbing performance test result is determined.

[0094] It should be noted that the preset shoulder creep calculation model is a mathematical or numerical analysis model used to simulate and calculate the movement behavior of the ball relative to the raceway under different load conditions. The model comprehensively considers the geometric structure, material properties and working conditions of the ball screw, and simulates the movement of the ball under eccentric load conditions by setting specific boundary conditions and parameters, such as the limit contact angle, load distribution, etc., especially the creep phenomenon of the ball at the shoulder. The creep rate refers to the proportion of the sliding or creeping of the ball relative to the raceway due to eccentric load or uneven load distribution during the rolling process of the ball. This indicator reflects the relative displacement of the ball along the raceway when the force is uneven, expressed as a percentage. A high creep rate means that the ball has significantly slid on the raceway, which may affect the accuracy and life of the ball screw. The design requirements refer to the load and contact angle range that needs to be met in the actual working conditions of the designed ball screw.

[0095] It is understood that the limiting contact angle is the maximum contact angle between the ball and the raceway, which is used to evaluate the maximum sliding range that may occur when the ball rolls. Then, a pre-set shoulder creep calculation model is used. This model combines the geometric structure, material properties and working conditions of the ball screw to calculate the creep rate of the ball under eccentric load conditions through numerical analysis or simulation. The creep rate reflects the sliding ratio of the ball relative to the raceway when the force is uneven. The calculated creep rate and design requirements are used to finally determine the shoulder creep performance test results of the ball screw under these specific conditions. This result can indicate whether the ball screw meets the expected performance standards and whether design optimization or process improvement is required to ensure its reliability and performance in actual applications.

[0096] As an example, based on the limit contact angle of the screw, the climbing rate of the ball of the ball screw under the eccentric load condition is obtained by presetting the shoulder climbing calculation model, and based on the climbing rate and design requirements, the shoulder climbing performance test results of the ball screw are determined, including: based on the limit contact angle and the structural parameters, the maximum allowable axial load of the ball screw under uniform load is obtained; based on the maximum allowable axial load under uniform load and the uniform load coefficient, the maximum allowable axial load under eccentric load is obtained; based on the limit contact angle, the structural parameters and the operating parameters, the maximum allowable design contact angle under uniform load is obtained; based on the limit contact angle, the uniform load coefficient, the structural parameters and the operating parameters, the maximum allowable design contact angle under eccentric load is obtained; when at least one of the following conditions is met: the actual axial load is greater than the maximum allowable axial load under uniform load, the actual axial load is greater than the maximum allowable axial load under eccentric load, the actual contact angle is greater than the maximum allowable design contact angle under uniform load, and the actual contact angle is greater than the maximum allowable design contact angle under eccentric load, the ball screw is determined to have shoulder climbing. Their formulas are:

[0097]

[0098] Among them, f e f is the ratio of the nut raceway radius to the ball diameter, i f is the ratio of the screw raceway radius to the ball diameter, m R is the comprehensive ball raceway radius ratio, e -r 1e is the shoulder height, ε E is the material coefficient at the time of initial contact, eδ is the elastic deformation coefficient, c is the contact deformation coefficient of the relative approach of the inner and outer rings, θ is the angle between the line connecting the center of curvature of the nut groove and the edge of the shoulder and the center line of the outer ring groove, e a The Hertz value will exceed the semimajor axis coefficient.

[0099] Among them, the maximum allowable axial load of the ball screw under uniform load refers to the maximum axial load that can be borne when all balls in the ball screw system are evenly loaded. This value is based on the structural parameters and the limit contact angle to ensure that the system will not be overloaded or fail when the load is uniform. The maximum allowable axial load under eccentric load refers to the maximum axial load that the system can withstand when the load is unevenly distributed in the ball screw system. This load value takes into account the load coefficient and the maximum allowable axial load under uniform load, reflecting the load-bearing capacity under uneven load conditions. The maximum allowable design contact angle under uniform load refers to the maximum contact angle designed under uniform load conditions. It is calculated based on the limit contact angle, structural parameters and operating parameters to ensure that the contact angle will not exceed the design limit under uniform load conditions, thereby avoiding excessive stress and deformation. The maximum allowable design contact angle under eccentric load is the maximum contact angle designed under eccentric load conditions, reflecting the design limit of the contact angle under uneven load conditions. Shoulder creep refers to the phenomenon in the ball screw system that the ball climbs out of the groove of the screw or nut due to excessive axial load or contact angle. Shoulder creep will cause the ball screw to fail, which may result in serious mechanical failure or damage. aL , maximum permissible axial load F aLPz , the maximum allowable design contact angle a under uniform load 01 , the maximum eccentric load allowable design contact angle a 02 The formula is:

[0100]

[0101] When designing and evaluating a ball screw system, it is first necessary to calculate the maximum axial load that the ball screw can withstand under uniform load conditions. This is called the maximum allowable axial load for even load, which is determined by the limit contact angle and structural parameters. Next, based on the maximum allowable axial load and the even load coefficient under even load conditions, calculate the maximum axial load that the ball screw can withstand under eccentric load conditions, that is, the maximum allowable axial load for eccentric load. Then, based on the limit contact angle, structural parameters and operating parameters, determine the maximum design contact angle under even load conditions, that is, the maximum allowable design contact angle for even load. Similarly, the maximum allowable design contact angle for eccentric load under eccentric load conditions is calculated based on the limit contact angle, even load coefficient, structural parameters and operating parameters. Finally, if the axial load under actual working conditions exceeds the maximum allowable axial load for even load, or exceeds the maximum allowable axial load for eccentric load, and the actual contact angle is also greater than at least one of the maximum allowable design contact angle for even load or the maximum allowable design contact angle for eccentric load, it can be determined that the ball screw has experienced shoulder creep. This phenomenon refers to the situation where the ball cannot work properly in the groove of the screw due to excessive load or the contact angle does not meet the design requirements, causing the ball to climb out of the groove, resulting in system failure or damage.

[0102] As an example, based on the limit contact angle of the screw, the climbing rate of the ball of the ball screw under the eccentric load condition is obtained by preset shoulder climbing calculation model, including: based on the load distribution coefficient, the structural parameters and the actual working conditions, the actual eccentric load contact angle is obtained; based on the actual eccentric load contact angle and the limit contact angle, the climbing rate of the ball screw under the eccentric load condition is obtained.

[0103] The actual contact angle refers to the contact angle between the ball and the screw channel under actual operating conditions. It reflects the contact between the ball and the screw under actual load and operating conditions. The actual contact angle will be affected by the actual working conditions (such as axial load, eccentric load, etc.), and it will be different from the limit contact angle set during design (i.e. the theoretical maximum contact angle).

[0104] When analyzing the performance of a ball screw under eccentric load conditions, it is first necessary to calculate the actual eccentric load contact angle through the load distribution factor, structural parameters and actual working conditions. This contact angle reflects the contact state of the ball under actual eccentric load conditions, and is affected by the load distribution and the actual working environment. Then, compare this actual eccentric load contact angle with the limit contact angle to determine the creep rate of the ball screw. The limit contact angle is the maximum contact angle that the ball screw can theoretically withstand. Exceeding this angle may cause the system to degrade in performance or fail. The creep rate indicates the ratio between the actual contact angle and the limit contact angle under eccentric load conditions, reflecting the stability and load-bearing capacity of the ball screw under actual working conditions. The creep rate calculation formula is:

[0105] Average load:

[0106] When the load is off-center:

[0107] Among them, lv J ,lv P are the shoulder climbing rates under uniform load and eccentric load conditions, α1 and α2 are the limit contact angles under uniform load and eccentric load conditions, respectively. max is the limiting contact angle.

[0108] The present embodiment provides a method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution. The present application determines the load-bearing coefficient of the ball screw and obtains the limit contact angle of the screw by comprehensively considering the structural parameters, material parameters and operating conditions of the ball screw. The preset shoulder climbing calculation model is used to obtain the climbing rate of the ball screw under eccentric load conditions. The method can accurately detect and analyze the shoulder climbing performance of the ball screw under non-uniform load distribution conditions, thereby realizing effective detection and evaluation of the key performance of the ball screw.

[0109] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can refer to the above introduction, and will not be repeated later. Figure 2 , Figure 2 This is a flow chart of the second embodiment of the ball screw shoulder climbing performance detection method with non-uniform load distribution of the present application. Step S10 of the ball screw shoulder climbing performance detection method with non-uniform load distribution includes steps S11 to S14:

[0110] Step S11, based on the normal force and structural parameters borne by the single ball, a correction coefficient based on finite element and experimental results is introduced to obtain the axial strain of the nut and the screw and the constant term of the coordination equation;

[0111] It should be noted that the correction coefficients of finite element and experimental results refer to the correction coefficients introduced in the calculation process based on finite element analysis and actual experimental data in order to improve accuracy. Finite element analysis predicts the stress, strain and deformation of ball screws under different working conditions through numerical simulation, while the experimental results provide real data under actual operating conditions. The correction coefficient is used to adjust the theoretical prediction of the calculation model to make it consistent with the actual situation, thereby improving the accuracy of the calculation results. The axial strain of the nut and screw refers to the deformation of the nut and screw in the axial direction under the action of external loads. The axial strain is the ratio of the length change of the material under axial force to the original length. The axial strain of the nut and screw reflects their deformation under force conditions and is of great significance for evaluating the performance and stability of the ball screw system. The constant terms of the coordination equation refer to the constant terms involved in establishing the coordination equation that describes the mechanical behavior of the nut and screw system. These constant terms include the mechanical properties of the material, such as elastic modulus, Poisson's ratio, etc., which are used to calculate the mechanical equilibrium and stress-strain relationship of the system. The coordination equation ensures that the mechanical model can accurately describe the deformation and stress of the system under different working conditions.

[0112] It is understandable that the introduction of correction coefficients based on finite element and experimental results based on the normal force on each ball during operation can improve the accuracy of the calculation model. Finite element analysis provides a numerical simulation platform that can predict the stress and deformation of the ball screw system under different working conditions. However, the theoretical model may deviate from the actual situation, so these models need to be corrected by actual experimental data. The correction coefficient is to adjust the finite element model based on the experimental results to better reflect the situation under actual working conditions. Through these correction coefficients, we can calculate the axial strain of the nut and the screw, which is a key indicator for evaluating the performance and stability of the ball screw system. Finally, the constant term of the coordination equation is calculated, which is a parameter that needs to be determined when establishing the coordination equation that describes the mechanical behavior of the ball screw system, to ensure that the mechanical model can accurately describe the stress-strain relationship of the system under different working conditions, thereby providing reliable data support for system design and performance evaluation.

[0113] Step S12, establishing a group of algebraic equations for normal loads of all balls based on the constant term of the coordination equation, the normal force on the ball, the working condition parameters, the elastic deformation coefficient and the plastic deformation coefficient of the contact point between the ball and the screw;

[0114] It should be noted that the elastic deformation coefficient refers to the elastic deformation ability of the contact points between the ball and the screw when the normal force acts on them, which reflects the deformation characteristics of the material within the elastic range. The plastic deformation coefficient refers to the ability of the contact point material to undergo plastic deformation after it exceeds the elastic range, which reflects the strain characteristics of the material during the plastic deformation stage. The algebraic equations for the normal load of the ball is a mathematical model used to describe the normal load borne by all the balls in the system under actual working conditions. This equation group is established based on factors such as the constant term of the coordination equation, the normal force borne by the ball, the operating parameters, the elastic deformation coefficient, and the plastic deformation coefficient. It reflects the load distribution of each ball under specific conditions through algebraic equations. By solving these equations, the normal load actually borne by each ball can be calculated, thereby evaluating the performance of the entire ball screw system under various working conditions. Among them, the algebraic equations for the normal load of the ball, which specifically include the constant term of the coordination equation, are established by combining the normal force, the operating parameters, the elastic deformation coefficient of the contact point between the ball and the screw, and the plastic deformation coefficient:

[0115]

[0116] Where Z is the number of balls, Pj is the normal force on the jth ball from the screw or nut side, Fa is the axial load on the screw, K1 is the elastic deformation coefficient, K2 is the plastic deformation coefficient, and ΔL is the average axial distance between two adjacent balls.

[0117] It is understandable that a set of parameters related to the ball screw system need to be considered, including the coordination equation constant, the normal force on the ball, the operating parameters, the elastic deformation coefficient, and the plastic deformation coefficient to establish the algebraic equations for the normal load of all balls. In fact, these parameters are substituted into the mathematical model to generate a set of equations for calculating and describing the normal loads borne by all balls under specific operating conditions. These equations accurately reflect the deformation of the contact point between the ball and the screw under actual load by combining the elastic and plastic deformation coefficients, thereby providing a comprehensive understanding and evaluation of the performance of the entire ball screw system.

[0118] Step S13, based on the normal load algebraic equation group, obtaining the influence of the contact angle and the axial load on the eccentric load;

[0119] It should be noted that the influence of contact angle and axial load on eccentric load means that the change of contact angle will affect the contact stress distribution between the ball and the screw. The change of contact angle will cause uneven load distribution of the ball at the contact point, affecting the force state and friction of the ball; the distribution of axial load will change under eccentric load conditions, affecting the force between the ball and the screw, increasing the stress borne by some balls, and affecting the overall load transfer. In this experiment, it is concluded that the change of contact angle has little effect on the eccentric load coefficient and can be ignored. However, the larger the contact angle, the lower the Hertzian contact stress of a single ball, the ratio of permanent deformation to ball diameter, and the normal load of a single ball is significantly reduced.

[0120] It is understandable that the equations can reveal the effect of contact angle changes on the contact stress distribution between the ball and the screw. When an eccentric load exists, the change in contact angle may lead to uneven force distribution between the ball and the screw, which in turn affects the bearing capacity of the ball and the operating stability of the screw. The equations can also be used to analyze the change of axial load under eccentric load conditions. Eccentric loads may cause uneven distribution of axial loads in the ball screw system, thereby affecting the force state of the ball and the screw and the overall transmission efficiency. Through these analyses, the specific effects of contact angle and axial load on system performance under eccentric load conditions can be understood, thereby providing a basis for optimizing design and improving manufacturing.

[0121] Step S14, referring to the influence of the contact angle and the axial load on the eccentric load, and obtaining the load sharing coefficient based on the average normal load and the maximum normal load.

[0122] It should be noted that the average normal load refers to the average value of the normal load measured on all balls. When calculating, the normal load of all balls is summed up and then divided by the number of balls to obtain the average normal load. The maximum normal load refers to the maximum normal load borne by a certain ball among all balls. In actual working conditions, due to factors such as eccentric loading, some balls may bear a greater load than other balls. Therefore, it is necessary to find the maximum load value among all balls, which reflects the load bearing capacity under the most unfavorable conditions. The load-sharing coefficient is a coefficient used to describe the load uniformity of the ball screw under actual working conditions. The load-sharing coefficient is usually calculated by the ratio of the average normal load to the maximum normal load to evaluate the load distribution of the ball screw under eccentric loading conditions. This coefficient is used to measure the uniformity of the load distribution. The closer the value is to 1, the more uniform the load distribution is; the lower the value is, the more uneven the load distribution is.

[0123] It is understandable that the impact of contact angle and axial load on ball screws under actual eccentric load conditions needs to be considered, including studying how the normal load distribution of the ball screw will be affected under different contact angles and loads. By calculating the average normal load and maximum normal load of all balls, the load conditions borne by each ball in actual operation are evaluated. Finally, these two load values ​​are used to calculate the load-averaging factor, which reflects the uniformity of the ball screw load under given conditions.

[0124] In this embodiment, first, by analyzing the normal force and structural parameters borne by a single ball, and introducing correction coefficients based on finite element analysis and experimental results, the axial strain of the nut and the screw and the constant term in the coordination equation are determined. This process enables us to accurately evaluate the strain of the nut and the screw under different loads under actual working conditions, and provides basic data for subsequent calculations. Then, based on the constant term of the coordination equation, the normal force borne by the ball, the working condition parameters, and the elastic and plastic deformation coefficients of the contact points between the ball and the screw, the normal load algebraic equation group of all balls is established. This equation group comprehensively considers various influencing factors and can describe in detail the normal load distribution of the ball under different working conditions. Then, by solving the normal load algebraic equation group, the influence of the contact angle and axial load on the eccentric load is obtained. This result reveals how the contact angle and axial load affect the performance of the ball screw under eccentric load conditions, and helps to understand the load distribution characteristics of the ball in actual work. Finally, referring to the influence of contact angle and axial load on eccentric load, and based on the average normal load and maximum normal load of all balls, the load distribution coefficient is calculated. The load distribution coefficient reflects the uniformity of the ball screw load distribution under actual working conditions, thus providing an important basis for the performance evaluation of the ball screw.

[0125] For example, in order to help understand the implementation process of the ball screw shoulder climbing performance detection method with non-uniform load distribution obtained by combining this embodiment with the above-mentioned embodiment 1, please refer to Figure 3 , Figure 3 A brief flow chart of a method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution is provided, specifically:

[0126] This flowchart describes the detailed steps of the ball screw shoulder creep performance detection method with non-uniform load distribution: first, the structural parameters, material parameters and working condition parameters are obtained, and based on these parameters, the normal force borne by a single ball, the principal curvature of the Hertz contact, the elliptic integral, the major and minor axis lengths of the Hertz contact, the elastic deformation coefficient, and the limiting contact angle are obtained; then, based on the normal force and the major and minor axis lengths of the Hertz contact, the maximum contact stress of a single ball under uniform load conditions is obtained, and the elastic deformation coefficient K1 is calculated; then, based on the maximum contact stress, principal curvature, and the major and minor axis length coefficients of the Hertz contact, the elastic deformation coefficient K2 is obtained. The critical normal load of the shape is calculated; then, based on the elastic deformation coefficient of the Hertz contact, the maximum elastic deformation, the material parameters, and the principal curvatures, the plastic deformation coefficient K2 between the ball and the screw is obtained; based on the normal force and structural parameters borne by the single ball, a correction coefficient based on finite element and experimental results is introduced to obtain the constant term of the equivalent strain coordination equation of the nut and the screw, and establish a group of algebraic equations for the normal load of all balls; the influence of the contact angle and axial load changes on the eccentric load is calculated through the group of equations, and the load-balancing coefficient is calculated; finally, based on the limit contact angle, the limit load F under the eccentric load and the eccentric load is calculated. al 、F aL Pz , the maximum allowable design contact angle α 01 , α 02 By calculating the actual contact angles α1 and α2 under uniform load and eccentric load conditions, the shoulder climbing rate lv under uniform load and eccentric load conditions can be obtained respectively. J ,lv P .

[0127] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the ball screw shoulder climbing performance detection method with non-uniform load distribution of the present application. More simple transformations based on this technical concept are all within the protection scope of the present application.

[0128] This application also provides a ball screw shoulder climbing performance detection device with non-uniform load distribution, please refer to Figure 4 The ball screw shoulder climbing performance detection device with non-uniform load distribution includes:

[0129] A calculation module 10, for determining a load sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters of the ball screw based on the structural parameters, material parameters and operating parameters of the ball screw;

[0130] An acquisition module 20, for acquiring a limit contact angle of the lead screw based on the structural parameters, material parameters and working condition parameters;

[0131] Obtain module 30, which is used to obtain the climbing rate of the ball of the ball screw under eccentric load conditions based on the limit contact angle of the screw and through a preset shoulder climbing calculation model, and to determine the ball screw shoulder climbing performance test result based on the climbing rate and design requirements.

[0132] The ball screw shoulder climbing performance detection device with non-uniform load distribution provided by the present application adopts the ball screw shoulder climbing performance detection method with non-uniform load distribution in the above embodiment, which can solve the technical problem of how to accurately detect the shoulder climbing performance of the ball screw under non-uniform load distribution conditions. Compared with the prior art, the beneficial effects of the ball screw shoulder climbing performance detection device with non-uniform load distribution provided by the present application are the same as the beneficial effects of the ball screw shoulder climbing performance detection method with non-uniform load distribution provided by the above embodiment, and the other technical features of the ball screw shoulder climbing performance detection device with non-uniform load distribution are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0133] The present application provides a ball screw shoulder creep performance detection device with non-uniform load distribution, the ball screw shoulder creep performance detection device with non-uniform load distribution comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the ball screw shoulder creep performance detection method with non-uniform load distribution in the above-mentioned embodiment one.

[0134] Reference below Figure 5, which shows a schematic diagram of the structure of a ball screw shoulder creep performance detection device suitable for realizing the non-uniform load distribution of the embodiment of the present application. The ball screw shoulder creep performance detection device with non-uniform load distribution in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 5 The ball screw shoulder climbing performance detection device with non-uniform load distribution shown is only an example and should not bring any limitation to the function and scope of use of the embodiments of the present application.

[0135] like Figure 5 As shown, the ball screw shoulder climbing performance detection device with non-uniform load distribution may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM: Read Only Memory) 1002 or the program loaded from the storage device 1003 to the random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the ball screw shoulder climbing performance detection device with non-uniform load distribution are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other through a bus 1005. The input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; storage devices 1003 including, for example, a magnetic tape, a hard disk, etc.; and communication devices 1009. The communication device 1009 can allow the ball screw shoulder creep performance detection device with non-uniform load distribution to communicate with other devices wirelessly or wired to exchange data. Although the figure shows a ball screw shoulder creep performance detection device with non-uniform load distribution having various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have instead.

[0136] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0137] The ball screw shoulder climbing performance detection device with non-uniform load distribution provided by the present application adopts the ball screw shoulder climbing performance detection method with non-uniform load distribution in the above embodiment, which can solve the technical problem of how to accurately detect the shoulder climbing performance of the ball screw under non-uniform load distribution conditions. Compared with the prior art, the beneficial effects of the ball screw shoulder climbing performance detection device with non-uniform load distribution provided by the present application are the same as the beneficial effects of the ball screw shoulder climbing performance detection method with non-uniform load distribution provided by the above embodiment, and the other technical features of the ball screw shoulder climbing performance detection device with non-uniform load distribution are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0138] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0139] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0140] The present application provides a computer-readable storage medium having computer-readable program instructions (i.e., computer programs) stored thereon, and the computer-readable program instructions are used to execute the ball screw shoulder climbing performance detection method with non-uniform load distribution in the above-mentioned embodiment.

[0141] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0142] The above-mentioned computer-readable storage medium may be included in the ball screw shoulder creep performance detection device with non-uniform load distribution; or it may exist independently without being assembled into the ball screw shoulder creep performance detection device with non-uniform load distribution.

[0143] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by the ball screw shoulder creeping performance detection device with non-uniform load distribution, the ball screw shoulder creeping performance detection device with non-uniform load distribution: determines the load-balanced coefficient of the ball screw under the structural parameters, material parameters and operating parameters based on the structural parameters, material parameters and operating parameters of the ball screw; obtains the limit contact angle of the screw based on the structural parameters, material parameters and operating parameters; obtains the creeping rate of the ball of the ball screw under the eccentric load condition based on the limit contact angle of the screw through a preset shoulder creeping calculation model, and determines the test result of the ball screw shoulder creeping performance based on the creeping rate and design requirements.

[0144] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0145] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0146] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0147] The readable storage medium provided by the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution, and can solve the technical problem of how to accurately detect the shoulder climbing performance of a ball screw under non-uniform load distribution conditions. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present application are the same as the beneficial effects of the method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution provided by the above-mentioned embodiment, and will not be elaborated here.

[0148] The present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the ball screw shoulder climbing performance detection method with non-uniform load distribution as described above.

[0149] The computer program product provided by the present application can solve the technical problem of how to accurately detect the shoulder climbing performance of a ball screw under non-uniform load distribution conditions. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the ball screw shoulder climbing performance detection method under non-uniform load distribution provided by the above embodiment, and will not be elaborated here.

[0150] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution, characterized in that: The method comprises: Determining, based on structural parameters, material parameters, and operating parameters of the ball screw, a load sharing coefficient of the ball screw under the structural parameters, material parameters, and operating parameters; Based on the structural parameters, material parameters and working condition parameters, a limit contact angle of the lead screw is obtained; Based on the limit contact angle of the screw, the climbing rate of the ball of the ball screw under the eccentric load condition is obtained by presetting the shoulder climbing calculation model. Based on the climbing rate and design requirements, the test results of the ball screw shoulder climbing performance are determined.

2. The method according to claim 1, wherein The determining, based on the structural parameters, material parameters, and operating parameters of the ball screw, a load sharing coefficient of the ball screw under the structural parameters, material parameters, and operating parameters, includes: Based on the normal force borne by a single ball and the semi-minor axis length of the Hertzian contact length, the maximum contact stress of a single ball under uniform load conditions is obtained; Obtaining an elastic deformation coefficient of a contact point between the ball and the screw based on a Hertz contact elastic deformation coefficient, a principal curvature of the ball and the screw, and material parameters; Obtaining a critical normal load for generating plastic deformation based on the maximum contact stress, the principal curvature sum, the Hertzian contact length semi-minor axis length coefficient, and the material parameters; When the normal force borne by the ball is greater than the critical normal load, the plastic deformation coefficient between the ball and the screw is obtained based on the elastic deformation coefficient of the Hertzian contact, the maximum elastic deformation, the material parameters, and the sum of the principal curvatures; The load sharing coefficient is obtained based on the elastic deformation coefficient of the contact point between the ball and the screw, the plastic deformation coefficient between the ball and the screw, the structural parameters and the working condition parameters.

3. The method according to claim 2, wherein The load sharing coefficient is obtained based on the elastic deformation coefficient of the contact point between the ball and the screw, the plastic deformation coefficient between the ball and the screw, the structural parameters, and the working condition parameters, including: Based on the normal force and structural parameters borne by the single ball, a correction coefficient based on finite element and experimental results is introduced to obtain the axial strain of the nut and screw and the constant term of the coordination equation; Based on the constant term of the coordination equation, the normal force on the ball, the working condition parameters, the elastic deformation coefficient and the plastic deformation coefficient of the contact point between the ball and the screw, a group of algebraic equations for the normal load of all balls is established; Based on the normal load algebraic equations, the influence of contact angle and axial load on eccentric load is obtained; With reference to the influence of contact angle and axial load on eccentric load, the load distribution coefficient is obtained based on the average normal load and maximum normal load.

4. The method according to claim 1, wherein Before determining the load sharing coefficient of the ball screw under the structural parameters, material parameters and operating parameters of the ball screw based on the structural parameters, material parameters and operating parameters, the method further includes: Based on the working condition parameters and structural parameters, the normal force borne by a single ball and the principal curvature of the Hertzian contact are obtained; Based on the principal curvature of the Hertzian contact, the first kind of elliptic integral, the second kind of elliptic integral and the equivalent radius of the Hertzian contact in each direction are obtained; Based on the second kind of elliptic integral and the equivalent radius of the Hertzian contact in each direction, the semi-minor axis length coefficient of the Hertzian contact is obtained; Based on the first kind of elliptic integral, the second kind of elliptic integral and the equivalent radius of the Hertzian contact in each direction, an elastic deformation coefficient of the Hertzian contact is obtained; The major and minor semi-axis lengths of the Hertzian contact are obtained based on the principal curvature of the Hertzian contact, the operating parameters, the material parameters, the major and minor semi-axis length coefficients of the Hertzian contact, and the elastic deformation coefficient of the Hertzian contact.

5. The method according to claim 1, wherein The obtaining of the limit contact angle of the screw based on the structural parameters, material parameters and working condition parameters includes: Based on the structural parameters, the angle between the line connecting the center of curvature of the nut raceway and the edge of the shoulder and the centerline of the outer raceway is calculated; The limiting contact angle of the screw is obtained based on the angle between the line connecting the center of curvature of the nut groove and the edge of the shoulder and the center line of the outer ring groove, the structural parameters, the operating parameters, the material parameters, the length of the major and minor axes of the Hertzian contact, and the sum of the main curvatures.

6. The method according to claim 1, wherein The method of determining the ball creep rate of the ball screw under eccentric load conditions based on the limit contact angle of the screw and the preset shoulder creep calculation model is as follows: Based on the limit contact angle and the structural parameters, a maximum uniformly loaded allowable axial load of the ball screw is obtained; Based on the maximum allowable axial load under the load distribution and the load distribution coefficient, a maximum allowable axial load under eccentric load is obtained; Based on the limit contact angle, the structural parameters and the operating condition parameters, a maximum load-balanced allowable design contact angle is obtained; Based on the limit contact angle, the load-sharing coefficient, the structural parameters, and the operating parameters, a maximum eccentric load allowable design contact angle is obtained; When at least one of the following conditions is met: the actual axial load is greater than the maximum allowable axial load under uniform load, the actual axial load is greater than the maximum allowable axial load under partial load, the actual contact angle is greater than the maximum allowable design contact angle under uniform load, and the actual contact angle is greater than the maximum allowable design contact angle under partial load, it is determined that shoulder creep has occurred in the ball screw.

7. The method according to claim 1, wherein The method of obtaining the ball creep rate of the ball screw under eccentric load conditions based on the limit contact angle of the screw and a preset shoulder creep calculation model includes: Based on the load-sharing coefficient, the structural parameters and the actual working conditions, an actual eccentric load contact angle is obtained; Based on the actual eccentric load contact angle and the limit contact angle, the creep rate of the ball screw under eccentric load conditions is obtained.

8. A device for detecting the climbing performance of a ball screw shoulder with non-uniform load distribution, characterized in that: The device comprises: a calculation module, configured to determine, based on structural parameters, material parameters, and operating parameters of the ball screw, a load sharing coefficient of the ball screw under the structural parameters, material parameters, and operating parameters; An acquisition module, configured to acquire a limit contact angle of the lead screw based on the structural parameters, material parameters, and working condition parameters; A module is obtained, which is used to obtain the climbing rate of the ball of the ball screw under the condition of eccentric load based on the limit contact angle of the screw and the preset shoulder climbing calculation model, and to determine the test result of the shoulder climbing performance of the ball screw based on the climbing rate and design requirements.

9. A ball screw shoulder climbing performance testing device with non-uniform load distribution, characterized in that: The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the method for detecting the shoulder climbing performance of a ball screw with non-uniform load distribution as described in any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the ball screw shoulder climbing performance detection method with non-uniform load distribution as described in any one of claims 1 to 7 are implemented.

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