A device and method for accelerating the testing of the linearity degradation process of a machine tool feed system

Abstract

The present invention relates to the technical field of performance testing of CNC machine tool feed systems, and specifically to an accelerated testing device and method for the straightness degradation process of a machine tool feed system. The testing device includes a machine tool feed system, which is used to form an independent object to be tested; a multi-factor load loading system, which is used to load the three-dimensional static and dynamic forces, vibration loads and temperature cycle loads of the machine tool feed system; and an accuracy degradation information testing system, which is used to monitor and collect the degradation information of the machine tool feed system. The device and method of the present invention have the multi-factor load loading capability of vibration, temperature, static and dynamic forces, and feed speed, as well as the comprehensive testing capability of accuracy degradation information, which can realize the comprehensive analysis and testing of the degradation causes of the straightness degradation process of the machine tool feed system, and provide a complete solution for the accelerated testing of the straightness degradation process of the machine tool feed system.

Description

Technical Field

[0001] The present invention relates to the technical field of performance testing of a CNC machine tool feed system, and in particular to a device and method for accelerating testing of a straightness degradation process of a machine tool feed system. Background Art

[0002] At present, domestic CNC machine tools lag significantly behind advanced foreign machine tools, and insufficient precision retention is a core bottleneck restricting the competitiveness of domestic machine tools. Affected by multiple loads such as cutting force, vibration, and temperature, machine tool precision exhibits nonlinear degradation characteristics during service. The straightness of a machine tool's feed system is a fundamental indicator of its accuracy. Its rapid decline will have a devastating impact on the overall precision retention of the machine tool and warrants special attention. The degradation of the machine tool feed system's straightness is primarily influenced by factors such as the release of residual stress in the bed, degradation of preload at the bolted interface between the guide rail and the bed, and wear of the guide rail and slider assembly. However, there is a lack of a device for accelerating the degradation of machine tool feed system straightness that can simulate the effects of multiple loads in actual service, significantly limiting the research and testing of the machine tool straightness degradation process. Therefore, there is an urgent need to develop a device and method for accelerating the degradation process of machine tool feed system straightness to achieve both accelerated degradation and comprehensive testing of degradation information.

[0003] At present, a number of precision retention test devices for functional components such as ball screw pairs and guide rail pairs under simulated cutting forces have been developed in China. For example, Jiao Keru et al. from Shenyang Ligong University disclosed a ball screw pair precision retention test device and method based on real working conditions in patent CN109406143A, which studied the precision retention of ball screw pairs during the movement of the workbench by loading variable axial forces on the ball screw pairs. Feng Hutian et al. from Nanjing University of Science and Technology disclosed a ball screw pair precision retention test device in patent CN103115770A, which achieved continuous changes in axial loading force through steel cable transmission. Chu Hongyan et al. from Beijing University of Technology disclosed a precision retention test bench for multiple sets of parallel linear guide rail pairs under variable loads in patent CN116804591A, which simulated the load conditions of the guide rails in any direction through cylinders in three directions.

[0004] Through the analysis of the existing precision retention test devices for functional components such as ball screws and rolling guides, the following problems were found: (1) The existing test devices are only for single functional components such as ball screws and rolling guides, and lack precision retention test devices covering the overall feed system of the bed, rolling guides, and ball screws; (2) The existing test devices can only apply force while the tested sample is moving, ignoring the influence of environmental loads such as temperature and vibration on precision degradation; (3) The existing test devices lack the ability to comprehensively test degradation information such as preload, strain, vibration, temperature, and current. Summary of the Invention

[0005] The object of the present invention is to provide a device and method for accelerating the testing of the linearity degradation process of a machine tool feed system, so as to solve the problems existing in the prior art.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: the testing device comprises

[0007] A machine tool feed system for forming the object to be measured;

[0008] A multi-element load loading system for applying three-dimensional static and dynamic forces, vibration loads, and temperature cycle loads to the machine tool feed system;

[0009] and an accuracy degradation information testing system for monitoring and collecting degradation information of the machine tool feed system.

[0010] Furthermore, the machine tool feed system includes a machine tool, a machine tool motor, a ball screw, a machine tool guide rail, a worktable and a worktable slider: the machine tool motor is installed on the machine tool, the machine tool motor drives the ball screw to rotate, the ball screw is connected to the worktable through the screw nut, and the worktable slides on the machine tool guide rail through the worktable slider.

[0011] Furthermore, the multi-element load loading system includes a three-dimensional static and dynamic force loading mechanism, a vibration loading mechanism, and a temperature loading mechanism.

[0012] Furthermore, the three-way static and dynamic force loading mechanism includes a gantry, a vertical electric cylinder, a vertical tension and pressure sensor, a radial electric cylinder, a radial tension and pressure sensor, an axial electric cylinder, an axial tension and pressure sensor, a tailstock, a gantry screw, a gantry guide rail, a gantry motor, a tailstock slider and a gantry slider: the gantry motor is installed on the foundation, the gantry motor drives the gantry screw to rotate, the tailstock is fixedly connected to the gantry, the gantry screw is connected to the tailstock and the gantry through a screw nut, and respectively drives the tailstock through the tailstock slider and the gantry through the gantry slider to slide on the gantry guide rail; the radial electric cylinder and the vertical electric cylinder are installed on the gantry, The axial electric cylinder is installed on the tailstock; the ends of the output shafts of the vertical electric cylinder, the radial electric cylinder and the axial electric cylinder are fixedly connected to the vertical tensile pressure sensor, the radial tensile pressure sensor and the axial tensile pressure sensor respectively, and the vertical tensile pressure sensor, the radial tensile pressure sensor and the axial tensile pressure sensor are all fixedly connected to the simulated workpiece; the machine tool motor of the machine tool feed system and the gantry motor are synchronously controlled to drive the worktable and the gantry to move synchronously, and during the synchronous movement, the vertical electric cylinder, the radial electric cylinder and the axial electric cylinder apply three-dimensional simulated cutting force to the simulated workpiece, so as to realize the loading of three-dimensional static and dynamic forces during the movement of the worktable.

[0013] Furthermore, the vibration loading mechanism includes a vibration exciter: the vibration exciter is fixedly connected to the machine tool, and the vibration exciter is used to apply a vibration load to the machine tool feeding system.

[0014] Furthermore, the temperature loading mechanism includes an environmental chamber cover, an environmental chamber side block and an environmental chamber bottom plate: the machine tool and the gantry guide rail are placed on the environmental chamber bottom plate, the environmental chamber side block is fixed on one side of the machine tool feed system, and the environmental chamber cover is on the other side of the machine tool feed system. Slide grooves are respectively provided on both sides of the environmental chamber bottom plate, and the environmental chamber cover moves in the slide grooves; when the environmental chamber cover and the environmental chamber side block are in a closed state, the environmental chamber cover, the environmental chamber side block and the environmental chamber bottom plate form a closed environmental chamber, and at the same time, the temperature loading mechanism is in a working position, and the high and low temperatures inside the environmental chamber change periodically. The temperature loading mechanism is used to realize temperature cyclic load loading on the machine tool feed system.

[0015] Furthermore, the accuracy degradation information testing system includes

[0016] A strain collector for real-time monitoring of the deformation of the machine tool caused by the release of residual stress;

[0017] a bolt preload force measuring instrument, used to regularly test the preload force of the fastening bolts between the machine tool guide rail and the machine tool;

[0018] A vibration sensor for real-time monitoring of the wear of the rolling joint surface of the machine tool feed system;

[0019] A temperature sensor, used for real-time monitoring of the temperature rise of the machine tool feed system under the loading of the multi-load loading system;

[0020] A power sensor for monitoring in real time the change in input power of the machine tool feed system under the loading of the multi-load loading system;

[0021] and a straightness measuring instrument for periodically measuring the straightness of the feed system of said machine tool;

[0022] The strain collector, bolt preload measuring instrument, vibration sensor, temperature sensor, power sensor and straightness measuring instrument are all communicatively connected with the on-site control system of the machine tool feed system.

[0023] Based on the above technical problems, the present invention provides another testing method of a device for accelerating the testing of the straightness degradation process of a machine tool feed system, comprising the following steps:

[0024] S1. Install and position the feed system of the machine tool to be tested;

[0025] S2. Install and arrange the accuracy degradation information test system;

[0026] S3. The multi-load loading system performs step loading in the order of vibration-temperature-static and dynamic forces-feed speed;

[0027] S4. Real-time monitoring and acquisition of machine tool feed system straightness degradation information data.

[0028] Furthermore, the specific requirements for the multi-element load loading system to perform step loading in step S3 are:

[0029] First, load temperature, vibration, and three-dimensional static force, and then load temperature, feed speed, and three-dimensional dynamic force. The two loading combinations form a loading cycle; the load levels of step loading are set to 3, and the loading time of each load level is kept consistent. The total time of step loading is not less than 120h; among them, temperature loading controls the temperature rise and fall of the environmental chamber based on the machine tool temperature, and the temperature change range is used as the step amount for step loading; when vibration loading, first sweep the frequency of the machine tool feed system to obtain the frequency spectrum curve of the machine tool feed system, and select multiple resonant frequencies according to the frequency spectrum curve to perform vibration tests to separate the vibration magnitude, and use the vibration magnitude as the step amount for step loading; static and dynamic force loading takes the maximum feed resistance of the feed axis as the loading basis, and the magnitude of the force is used as the step amount for step loading.

[0030] Furthermore, the specific requirements for real-time monitoring and obtaining the linearity degradation information data of the machine tool feed system in step S4 are:

[0031] A bolt preload force measuring instrument is used to regularly test the preload force of the fastening bolt joint surface between the machine tool guide rail and the machine tool, and a straightness measuring instrument is used to regularly test the straightness of the machine tool feed system; measurements are performed at equal time intervals at each load level, and the number of measurements at each load level is not less than 5 times, until the total loading time reaches the test set value, and the test is terminated.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. The present invention is highly comprehensive and a single system can monitor and promptly detect all issues related to linearity degradation of a machine tool feed system.

[0034] 2. The present invention uses a multi-load loading system to achieve synchronous loading of "vibration - temperature - static and dynamic forces - feed speed" on the feed system.

[0035] 3. The present invention can fully simulate and accelerate the actual service conditions of the machine tool feed system, and can achieve accelerated degradation of the straightness of the feed system.

[0036] 4. The precision degradation information testing system of the present invention can comprehensively monitor and detect the evolution of multi-source information during the straightness degradation process of the feed system, and can provide sufficient data support for the analysis of the three major causes of straightness degradation of the feed system: bed creep, loosening of the bed guide rail joint surface, and wear of the guide rail slider joint surface.

[0037] 5. The present invention is based on the improvement of the existing device to be tested, and the test device is easy to assemble and disassemble and has high versatility.

[0038] 6. The present invention is also applicable to analyzing the effects of different casting aging processes and different assembly processes on the linearity degradation of machine tool feed systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0040] Figure 1 It is a schematic diagram of the working state of the three-way static and dynamic force loading mechanism of the present invention on the machine tool feed system;

[0041] Figure 2 It is an overall schematic diagram of the temperature loading mechanism of the present invention;

[0042] Figure 3 Schematic diagram of the accuracy degradation information testing system of the present invention;

[0043] Figure 4 It is a schematic flow chart of the accelerated testing method of the present invention.

[0044] In the figure: 1. Machine tool feed system; 11. Machine tool; 12. Machine tool motor; 13. Ball screw; 14. Machine tool guide rail; 15. Work table; 16. Work table slide; 2. Multi-element load loading system; 21. Three-axis static and dynamic force loading mechanism; 211. Gantry; 212. Vertical electric cylinder; 213. Vertical pull pressure sensor; 214. Radial electric cylinder; 215. Radial pull pressure sensor; 216. Axial electric cylinder; 217. Axial pull pressure sensor; 218. Tailstock; 219. Gantry screw; 220. Gantry guide rail; 221. Gantry motor; 222. Tailstock slider; 223. Gantry slider; 23. Vibration loading mechanism; 231. Vibrator; 24. Temperature loading mechanism; 241. Environmental chamber cover; 242. Environmental chamber side stop; 243. Environmental chamber bottom plate; 244. Environmental chamber; 3. Accuracy degradation information test system; 31. Strain collector; 32. Bolt preload force measuring instrument; 33. Vibration sensor; 34. Temperature sensor; 35. Power sensor; 36. Straightness measuring instrument; 4. Simulated workpiece; 5. Control system. DETAILED DESCRIPTION

[0045] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0046] See also Figure 1-2As shown, the present invention is an accelerated testing device for the straightness degradation process of a machine tool feed system, comprising a machine tool feed system 1, a multi-element load application system 2, and an accuracy degradation information testing system 3. The machine tool feed system 1 is used to form an independent test object. A simulated workpiece 4 is placed on the worktable 15 of the machine tool feed system 1. The three-way electric cylinder of the multi-element load application system 2 applies static and dynamic forces to the simulated workpiece 4 to simulate three-way cutting forces. The accuracy degradation information testing system 3 collects degradation information from the machine tool feed system 1.

[0047] It is understood that, based on actual use, the machine tool feed system 1 may include a machine tool 11, a machine tool motor 12, a ball screw 13, a machine tool guide rail 14, a worktable 15, and a worktable slide 16. The machine tool motor 12 is mounted on the machine tool 11, and the machine tool motor 12 drives the ball screw 13 to rotate. The ball screw 13 is connected to the worktable 15 via a screw nut, and the worktable 15 slides on the machine tool guide rail 14 via the worktable slide 16.

[0048] Based on the above, Figure 1 and Figure 2 As shown, the multi-element load loading system 2 includes a three-axis static and dynamic force loading mechanism 21 , a vibration loading mechanism 23 and a temperature loading mechanism 24 .

[0049] It is understood that, based on actual use, the three-axis static and dynamic force loading mechanism 21 may include a gantry 211, a vertical electric cylinder 212, a vertical tension and pressure sensor 213, a radial electric cylinder 214, a radial tension and pressure sensor 215, an axial electric cylinder 216, an axial tension and pressure sensor 217, a tailstock 218, a gantry screw 219, a gantry guide rail 220, a gantry motor 221, a tailstock slider 222, and a gantry slider 223. The gantry motor 221 is installed on the foundation, and the gantry motor 221 drives the gantry screw 219 to rotate. The tailstock 218 is fixedly connected to the gantry 211. The gantry screw 219 is connected to the tailstock 218 and the gantry 211 via a screw nut, and drives the tailstock 218 via the tailstock slider 222 and the gantry 211 via the gantry slider 223 to slide on the gantry guide rail 220. The radial electric cylinder 214 and the vertical electric cylinder 212 are mounted on the gantry 211, and the axial electric cylinder 216 is mounted on the tailstock 218. The ends of the output shafts of the vertical electric cylinder 212, the radial electric cylinder 214, and the axial electric cylinder 216 are fixedly connected to the vertical pull and pressure sensor 213, the radial pull and pressure sensor 215, and the axial pull and pressure sensor 217, respectively. The vertical pull and pressure sensor 213, the radial pull and pressure sensor 215, and the axial pull and pressure sensor 217 are all fixedly connected to the simulated workpiece 4. The machine tool feed system 1 synchronizes the machine tool motor 12 with the gantry motor 221 to drive the worktable 15 and the gantry 211 to move synchronously. During this synchronous movement, the vertical electric cylinder 212, the radial electric cylinder 214, and the axial electric cylinder 216 apply three-dimensional simulated cutting forces to the simulated workpiece 4, thereby applying three-dimensional static and dynamic forces to the worktable 15 during its movement.

[0050] It is understandable that, based on actual use, the vibration loading mechanism 23 includes a vibration exciter 231, which is fixedly connected to the machine tool 11. When the vibration exciter 231 is working, a vibration load is applied to the entire machine tool feeding system 1.

[0051] It is understood that, based on actual use, the temperature loading mechanism 24 includes an environmental chamber cover 241, an environmental chamber side guard 242, and an environmental chamber bottom plate 243. The machine tool 11 and the gantry guide rail 220 are placed on the environmental chamber bottom plate 243. The environmental chamber side guard 242 is fixed to one side of the machine tool feed system 1, and the environmental chamber cover 241 is on the other side of the machine tool feed system 1. Slide grooves are provided on both sides of the environmental chamber bottom plate 243, and the environmental chamber cover 241 moves within the slide grooves. When the environmental chamber cover 241 and the environmental chamber side guard 242 are in a closed state, the environmental chamber cover 241, the environmental chamber side guard 242, and the environmental chamber bottom plate 243 form a closed environmental chamber 244. At the same time, the temperature loading mechanism 24 is in the working position, and the high and low temperatures inside the environmental chamber 244 change periodically. The temperature loading mechanism 24 is used to implement temperature cyclic load loading on the machine tool feed system 1.

[0052] Based on the above, Figure 3 As shown, the precision degradation information testing system 3 includes: a strain collector 31, which is used to monitor the deformation of the machine tool 11 caused by the release of residual stress in real time; a bolt preload force measuring instrument 32, which is used to regularly test the preload force of the fastening bolts between the machine tool guide rail 14 and the machine tool 11; a vibration sensor 33, which is used to monitor the wear of the rolling joint surface of the machine tool feed system 1 in real time, specifically the wear of the screw nut pair and the bearing; a temperature sensor 34, which is used to monitor the temperature change of the machine tool feed system 1 under the loading of the multi-load loading system 2 in real time; a power sensor 35, which is used to monitor the change of the input power of the machine tool feed system 1 under the loading of the multi-load loading system 2 in real time; and a straightness measuring instrument 36, which is used to regularly measure the straightness of the machine tool feed system 1.

[0053] It is understood that, based on actual use, the strain gauge 31, bolt preload force gauge 32, vibration sensor 33, temperature sensor 34, power sensor 35, and straightness gauge 36 can be connected to different components of the machine tool feed system 1 and communicated with the field control system 5 of the machine tool feed system 1. The straightness gauge 36 is preferably a laser interferometer.

[0054] Example 1

[0055] This embodiment is a method for accelerating the testing of the linearity degradation process of a machine tool feed system 1. Figure 4 As shown, the specific usage process includes the following steps:

[0056] S1, installing and positioning the machine tool feed system 1 to be tested;

[0057] Specifically, the environmental chamber 244 is opened, the gantry 211 is moved to the far end, the machine tool feed system 1 to be tested is placed on the bottom plate 243 of the environmental chamber, the relative position of the gantry 211 and the workbench 15 is debugged, the vertical electric cylinder 212, radial electric cylinder 214 and axial electric cylinder 216 of the three-way static and dynamic force loading mechanism 21 are connected to the workbench 15 of the machine tool feed system 1 through the simulated workpiece 4, and the exciter 231 is installed at the specified position of the machine tool feed system 1.

[0058] S2. Install and arrange the accuracy degradation information test system 3;

[0059] Specifically, the three-dimensional strain rosette of the strain acquisition system is pasted on the side wall of the bed guide rail mounting surface, the vibration sensor 33 is arranged at the bearing seats and screw nuts at both ends of the feed system, the temperature sensor 34 is arranged at the bed, bearing seats at both ends, motor and screw nut of the machine tool feed system, and the power sensor 35 is arranged at the input end of the three-phase power of the servo motor of the feed system to monitor the changes in strain, vibration, temperature and power information in real time during the linearity degradation process of the machine tool feed system 1.

[0060] S3, in the order of vibration - temperature - static and dynamic forces - feed speed, the multi-element loading system 2 performs step loading;

[0061] Specifically, first load temperature, vibration, and three-dimensional static force, and then load temperature, feed speed, and three-dimensional dynamic force. The two loads are combined into a loading cycle. The load level of step loading is set to 3, and the loading time of each load level is kept consistent. The total time of step loading is not less than 120h. Among them, temperature loading controls the temperature rise and fall of the environmental chamber 244 based on the temperature of the machine tool 11, and the temperature change range is used as the step amount for step loading. During vibration loading, the machine tool feed system 1 is first swept to obtain the frequency spectrum curve of the machine tool feed system 1. According to the frequency spectrum curve, multiple resonant frequencies are screened for vibration testing to separate the vibration magnitude, and the vibration magnitude is used as the step amount for step loading. Static and dynamic force loading uses the maximum feed resistance of the feed shaft as the loading basis, and the magnitude of the force is used as the step amount for step loading. Among them, the maximum feed resistance of the feed shaft is limited when the equipment leaves the factory.

[0062] S4, real-time monitoring and acquisition of straightness degradation information data of the machine tool feed system 1;

[0063] Specifically, a bolt preload measuring instrument 32 is used to regularly test the preload force of the bolted joint between the machine tool guide rail 14 and the machine tool 11. A straightness measuring instrument 36 is used to regularly test the straightness of the machine tool feed system 1. Measurements are taken at equal intervals at each load level, and the number of measurements at each load level is no less than five. The test is terminated until the total loading duration reaches the set test value.

[0064] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed therein. Any reference in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A device for accelerating the testing of the linearity degradation process of a machine tool feed system, characterized in that: The test equipment includes A machine tool feeding system (1) for forming a measured object; A multi-element load loading system (2) for loading the machine tool feed system (1) with three-dimensional static and dynamic forces, vibration loads, and temperature cycle loads; and an accuracy degradation information testing system (3) for monitoring and collecting degradation information of the machine tool feed system (1); The machine tool feeding system (1) comprises a machine tool (11), a machine tool motor (12), a ball screw (13), a machine tool guide rail (14), a worktable (15) and a worktable slide block (16): the machine tool motor (12) is mounted on the machine tool (11), the machine tool motor (12) drives the ball screw (13) to rotate, the ball screw (13) is connected to the worktable (15) via a screw nut, and the worktable (15) slides on the machine tool guide rail (14) via the worktable slide block (16); The precision degradation information testing system (3) includes A strain collector (31) for real-time monitoring of the deformation of the machine tool (11) caused by residual stress release; a bolt preload force measuring instrument (32) for periodically testing the preload force of the fastening bolts between the machine tool guide rail (14) and the machine tool (11); A vibration sensor (33) for monitoring the wear of the rolling joint surface of the machine tool feed system (1) in real time; A temperature sensor (34) for real-time monitoring of the temperature rise of the machine tool feed system (1) under the loading of the multi-load loading system (2); A power sensor (35) for real-time monitoring of changes in input power of the machine tool feed system (1) under the loading of the multi-load loading system (2); and a straightness measuring instrument (36) for periodically measuring the straightness of the machine tool feed system (1); The strain collector (31), bolt preload measuring instrument (32), vibration sensor (33), temperature sensor (34), power sensor (35) and straightness measuring instrument (36) are all communicatively connected to the field control system (5) of the machine tool feed system (1).

2. The accelerated testing device for the linearity degradation process of a machine tool feed system according to claim 1, characterized in that: The multi-element load loading system (2) comprises a three-dimensional static and dynamic force loading mechanism (21), a vibration loading mechanism (23), and a temperature loading mechanism (24).

3. The accelerated testing device for the linearity degradation process of a machine tool feed system according to claim 2, characterized in that: The three-directional static and dynamic force loading mechanism (21) comprises a gantry (211), a vertical electric cylinder (212), a vertical tension pressure sensor (213), a radial electric cylinder (214), a radial tension pressure sensor (215), an axial electric cylinder (216), an axial tension pressure sensor (217), a tail frame (218), a gantry screw (219), a gantry guide rail (220), a gantry motor (221), a tail frame slider (222), and a gantry slider (223): the gantry motor (221) is installed on a foundation, The gantry motor (221) drives the gantry screw (219) to rotate, the tail frame (218) is fixedly connected to the gantry (211), the gantry screw (219) is connected to the tail frame (218) and the gantry (211) through a screw nut, and drives the tail frame (218) through the tail frame slider (222) and the gantry (211) through the gantry slider (223) to slide on the gantry guide rail (220); the radial electric cylinder (214) and the vertical electric cylinder (212) is mounted on the gantry (211), and the axial electric cylinder (216) is mounted on the tail frame (218); the output shaft ends of the vertical electric cylinder (212), the radial electric cylinder (214) and the axial electric cylinder (216) are respectively fixedly connected to the vertical pulling pressure sensor (213), the radial pulling pressure sensor (215) and the axial pulling pressure sensor (217), and the vertical pulling pressure sensor (213), the radial pulling pressure sensor (215) and the axial pulling pressure sensor (217) are fixedly connected to the tail frame (218); The pressure sensors (217) are all fixedly connected to the simulated workpiece (4); the machine tool motor (12) of the machine tool feeding system (1) and the gantry motor (221) are synchronously controlled to drive the worktable (15) and the gantry (211) to move synchronously, and during the synchronous movement, the vertical electric cylinder (212), the radial electric cylinder (214) and the axial electric cylinder (216) apply three-dimensional simulated cutting forces to the simulated workpiece (4), so as to realize the loading of three-dimensional static and dynamic forces during the movement of the worktable (15).

4. The device for accelerating the testing of the linearity degradation process of a machine tool feed system according to claim 2, characterized in that: The vibration loading mechanism (23) includes a vibration exciter (231): the vibration exciter (231) is fixedly connected to the machine tool (11), and the vibration exciter (231) is used to apply a vibration load to the machine tool feed system (1).

5. The accelerated testing device for the linearity degradation process of a machine tool feed system according to claim 3, characterized in that: The temperature loading mechanism (24) includes an environmental chamber cover (241), an environmental chamber side block (242) and an environmental chamber bottom plate (243): the machine tool (11) and the gantry guide rail (220) are placed on the environmental chamber bottom plate (243), the environmental chamber side block (242) is fixed on one side of the machine tool feed system (1), the environmental chamber cover (241) is on the other side of the machine tool feed system (1), and slide grooves are respectively provided on both sides of the environmental chamber bottom plate (243). The environmental chamber cover (241) is fixed on the other side of the machine tool feed system (1). The environmental chamber (244) moves in the slide; when the environmental chamber cover (241) and the environmental chamber side block (242) are in a closed state, the environmental chamber cover (241), the environmental chamber side block (242) and the environmental chamber bottom plate (243) form a closed environmental chamber (244), and at the same time, the temperature loading mechanism (24) is in a working position, and the high and low temperatures inside the environmental chamber (244) change periodically. The temperature loading mechanism (24) is used to realize temperature cycle load loading on the machine tool feed system (1).

6. A testing method for the accelerated testing device for the linearity degradation process of a machine tool feed system according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Install and position the feed system of the machine tool to be tested; S2. Install and arrange the accuracy degradation information test system; S3. The multi-element loading system performs step loading in the order of vibration - temperature - static and dynamic forces - feed speed; S4. Real-time monitoring and acquisition of machine tool feed system straightness degradation information data.

7. The testing method of the machine tool feed system straightness degradation process accelerated testing device according to claim 6, characterized in that: The specific requirements for the multi-element load loading system to perform step loading in step S3 are: First, load temperature, vibration, and three-dimensional static force, and then load temperature, feed speed, and three-dimensional dynamic force. The two loading combinations form a loading cycle; the load levels of step loading are set to 3, and the loading time of each load level is kept consistent. The total time of step loading is not less than 120h; among them, temperature loading controls the temperature rise and fall of the environmental chamber based on the machine tool temperature, and the temperature change range is used as the step amount for step loading; when vibration loading, first sweep the frequency of the machine tool feed system to obtain the frequency spectrum curve of the machine tool feed system, and select multiple resonant frequencies according to the frequency spectrum curve to perform vibration tests to separate the vibration magnitude, and use the vibration magnitude as the step amount for step loading; static and dynamic force loading takes the maximum feed resistance of the feed axis as the loading basis, and the magnitude of the force is used as the step amount for step loading.

8. The testing method of the machine tool feed system straightness degradation process accelerated testing device according to claim 6, characterized in that: The specific requirements for real-time monitoring and obtaining the straightness degradation information data of the machine tool feed system in step S4 are: A bolt preload force measuring instrument is used to regularly test the preload force of the fastening bolt joint surface between the machine tool guide rail and the machine tool, and a straightness measuring instrument is used to regularly test the straightness of the machine tool feed system; measurements are performed at equal time intervals at each load level, and the number of measurements at each load level is not less than 5 times, until the total loading time reaches the test set value, and the test is terminated.

Images