Device and method for testing comprehensive performance of ball screw pair by simulating real working condition

Abstract

The invention is suitable for the technical field of reliability test of numerical control machine tools, and provides a ball screw pair comprehensive performance test device and method for simulating real working conditions. The device comprises a ball screw pair, a test device base, a rolling guide rail pair, a grating ruler integrated installation unit, two sets of support driving units, a loading workbench, an axial force simulation loading unit, a tested workbench and a comprehensive performance detection unit. The two sets of supporting and driving units are distributed on the test device base in a staggered alignment manner and are respectively connected with the loading workbench and the tested workbench, and synchronous driving of the loading workbench and the tested workbench is realized through synchronous control; and the axial force simulation loading unit realizes static and dynamic simulation loading of the axial force through electro-hydraulic servo control. According to the invention, a test device and technical support are provided for carrying out the reliable comprehensive performance bench test of the ball screw pair, and the problems of the ball screw pair in the aspects of high-frequency dynamic load simulation loading, comprehensive performance test and motion tracking loading are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of reliability testing of numerically controlled machine tools, and in particular relates to a comprehensive performance testing device and method for a ball screw pair simulating real working conditions. Background Art

[0002] Manufacturing is the cornerstone of national economic development, and its level directly affects the country's economic growth, social stability and national defense strength. Among them, equipment manufacturing is the key technology of manufacturing, and CNC machine tools are the backbone of equipment manufacturing. Their quality, performance and ownership have become important indicators of a country's industrialization level and comprehensive national strength. As one of the key functional components of CNC machine tools, the reliability level of ball screw pairs directly affects the reliability level of the entire CNC machine tool. Therefore, the development of comprehensive performance test equipment and methods for ball screw pairs, and the performance test and reliability acceleration test are of great significance for detecting and improving the comprehensive performance of ball screw pairs. However, the current research on test benches for ball screw pairs at home and abroad is mainly focused on comprehensive performance test benches, precision retention test benches and friction torque test benches. In terms of the comprehensive performance research of ball screw pairs, most test benches are still in the no-load running-in or static loading stage, lacking the dynamic loading capability to simulate the actual processing conditions. This makes it impossible to truly simulate the actual working conditions of the ball screw pair, and thus it is impossible to accurately evaluate its performance and predict its operating status. At the same time, the test method for the comprehensive performance test bench of the ball screw pair is still not perfect.

[0003] In terms of the loading methods of ball screw pairs, the existing technologies mainly include mass block, pneumatic loading, hydraulic loading, electric cylinder loading, motor drag loading and magnetic powder brake loading, etc. Among them, the mass block loading method can only achieve static loading, and the other loading methods can achieve dynamic loading, but the loading frequency is low and cannot effectively simulate the actual working conditions of the ball screw pair.

[0004] In order to overcome the above technical problems, the present invention proposes a comprehensive performance test device and method for a ball screw pair that simulates real working conditions. Summary of the invention

[0005] The purpose of the present invention is to provide a ball screw pair comprehensive performance test device and method that simulates real working conditions, aiming to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A ball screw pair comprehensive performance test device simulating real working conditions, comprising a ball screw pair, wherein the ball screw pair comprises a ball screw, a screw nut and a ball; further comprising a test device base, a rolling guide pair, a grating ruler integrated installation unit, a support drive unit, a loading workbench, an axial force simulation loading unit, a tested workbench and a comprehensive performance detection unit;

[0008] The upper surface of the test device base is provided with a T-shaped groove;

[0009] The rolling guide pair is installed on the test device base and is used to connect the loading workbench and the tested workbench;

[0010] The grating ruler integrated installation unit is fixed on the test device base and connected to the loading workbench and the measured workbench, and is used to feed back the absolute positions of the loading workbench and the measured workbench to the numerical control system;

[0011] The support drive unit is used to realize the fixed support and drive of the ball screw pair. Two sets of support drive units are provided. The two sets of support drive units are distributed on the base of the test device in a staggered alignment manner, and the two sets of support drive units are respectively connected to the loading workbench and the workbench under test. The control system realizes the synchronous drive of the loading workbench and the workbench under test by synchronously controlling the two sets of support drive units.

[0012] The axial force simulation loading unit is fixed above the loading workbench and the workbench under test, and connects the loading workbench and the workbench under test; the axial force simulation loading unit realizes static and dynamic simulation loading of the axial force through electro-hydraulic servo control;

[0013] The comprehensive performance detection unit includes a positioning accuracy and repeatability detection module, a vibration signal detection module, a temperature detection module and a noise detection module; the positioning accuracy and repeatability detection module is used to calculate the positioning accuracy and repeatability of the ball screw; the vibration signal detection module and the temperature detection module are used to monitor the vibration data and temperature data of the ball screw pair; the noise detection module is used to monitor the environmental noise and working noise of the ball screw pair.

[0014] Furthermore, the rolling guide pair is composed of a rolling guide body and a rolling slider, which is installed on the base of the test device by fixing screws and guide fixing wedges; the lower surfaces of the loading workbench and the tested workbench are each fixed with four rolling sliders, and the rolling sliders are grouped in pairs and located on the left and right sides of the lower surface respectively, and the rolling sliders on the same side of the loading workbench and the tested workbench are slidably connected to a rolling guide body.

[0015] Furthermore, the grating ruler integrated installation unit includes a grating ruler installation bracket, a linear grating ruler, a grating ruler guide connecting plate and a drag chain slot;

[0016] The grating scale mounting bracket is installed on the surface of the test device base and is fixed to the T-nut in the T-slot on the test device base by screws; the linear grating scale consists of a grating scale bar and two reading heads, and is connected to the grating scale mounting bracket by screws; the grating scale guide connecting plates are provided with two, which are respectively connected to the two reading heads on the linear grating scale by screws, and the two reading heads are respectively connected to the loading workbench and the measured workbench; the drag chain slot is installed on the grating scale mounting bracket by screws and is used to place the drag chain.

[0017] Furthermore, the linear grating ruler is arranged in a central position to reduce Abbe measurement errors.

[0018] Further, the support drive unit includes a fixed support base, a rear support unit, a nut seat, a front support unit, a coupling, a servo motor, a circular grating mounting sleeve, a circular grating and a motor mounting seat;

[0019] The fixed supporting base is fixed to the T-nut in the T-slot on the base of the test device by screws, and the upper surface is used to install the rear supporting unit; the rear supporting unit and the front supporting unit are used to fix the two ends of the ball screw pair, and the rear supporting unit and the front supporting unit are respectively installed on the fixed supporting base and the motor mounting seat by screws; the nut seat is used to connect the screw nut in the ball screw pair, and is respectively fixed to the loading workbench and the measured workbench; the coupling is used to connect the servo motor and the ball screw pair; the servo motor is connected to the motor mounting seat by screws, and serves as the driving function power source of the ball screw pair; the circular grating mounting sleeve is connected to the output shaft of the servo motor by a flat key and a screw limiter; the circular grating includes a grating disk and a reading head, which are respectively connected to the circular grating mounting sleeve and the motor mounting seat by screws, and are used to detect the theoretical rotation angle of the ball screw pair; the motor mounting seat is connected to the base of the test device by screws.

[0020] Furthermore, the loading workbench and the measured workbench are used to realize the connection between the linear grating ruler, the ball screw pair and the axial force simulation loading unit.

[0021] Further, the axial force simulation loading unit includes a rear L-shaped plate, a hydraulic cylinder, a mounting raft plate, an electro-hydraulic servo valve, a front L-shaped plate, a loading connecting plate, a second connecting rod, an S-shaped tension and pressure sensor and a first connecting rod;

[0022] The rear L-shaped plate and the front L-shaped plate are connected to the loading workbench by screws and are used to install the hydraulic cylinder; the hydraulic cylinder serves as a power source for axial force simulation loading; the mounting raft is connected to the hydraulic cylinder by screws and is used to install the electro-hydraulic servo valve; the electro-hydraulic servo valve is connected to the mounting raft by screws, and cooperates with the electro-hydraulic servo valve amplifier in the control system to convert low-power electrical signal input into high-power hydraulic energy output, thereby realizing the displacement, speed, acceleration and force control of the hydraulic cylinder; the loading connecting plate is installed on the upper surface of the workbench to be tested and is connected to the second connecting rod by a double nut anti-loosening method, for the action and transmission of axial force; the two ends of the S-shaped tension and pressure sensor are respectively threadedly connected to the first connecting rod and the second connecting rod, for measuring the magnitude of the tension or pressure output by the hydraulic cylinder and for force closed-loop control; the first connecting rod is connected to the hydraulic cylinder by threads.

[0023] Furthermore, the positioning accuracy and repeatability accuracy detection module includes a laser interferometer, which is used to determine the combined detection method of the circular grating and the laser interferometer. The product of the rotation angle and the lead of the ball screw detected by the circular grating is used as the theoretical displacement, and the displacement detected by the laser interferometer is the actual displacement; the vibration signal detection module and the temperature detection module are fixedly installed on the surfaces of the rear support unit, the nut seat and the front support unit, the vibration signal detection module includes a three-axis acceleration sensor, and the temperature detection module includes a temperature sensor. The three-axis acceleration sensor and the temperature sensor are respectively used to monitor the vibration data and temperature data of the ball screw pair; the noise detection modules are distributed around the test bench and are one meter apart from the test bench.

[0024] A test method for the ball screw pair comprehensive performance test device simulating real working conditions as described above comprises the following steps:

[0025] T1. Preparation before the test;

[0026] T11. Determine the test object: determine the specifications and model of the ball screw pair to be tested, and select a suitable support drive unit;

[0027] T12. Install the ball screw pair: Install the ball screw pair to be tested on the test device;

[0028] T13. Test bench safety inspection: Check the locking condition of the test bench components, and the pressure of the hydraulic pump station and hydraulic cylinder;

[0029] T14. Debugging and testing equipment: Check the pasting and signal collection of the three-axis acceleration sensor and temperature sensor. After confirming that they are correct, turn on the laser interferometer and adjust the laser interferometer so that it is within the working range;

[0030] T15. Environmental testing and preparation: Ensure that the test environment is clean, the temperature is appropriate, and there is no sunlight interference;

[0031] T2. Turn on the test bench;

[0032] T21. Turn on the power of the test device;

[0033] T22, start the control system of the test bench, enter the test mode, and set the test parameters, including the driving speed, acceleration, and amplitude and frequency of the hydraulic loading;

[0034] T23. Confirm that the safety measures of the test bench have been activated;

[0035] T3. Conduct the test;

[0036] T31, Console input loader program spectrum: Use the console input loader program spectrum to set the operating parameters of the ball screw pair, including speed, load type, load amplitude and frequency;

[0037] T32, servo motor drive start: start the servo motor to drive the ball screw pair to operate, and control the servo system to run according to the speed requirements set in the loading program spectrum; at the same time, monitor the speed, power input and output of the ball screw pair through the encoder or circular grating, and record the data;

[0038] T33, static and dynamic force loading of hydraulic cylinder: according to the load requirements set in the loading program spectrum, the hydraulic cylinder is controlled by the electro-hydraulic servo control system to load the set load, and the force closed-loop control is achieved through the S-type tension and pressure sensor;

[0039] T34, comprehensive performance testing: including motion performance test, force load test, reliability life test, vibration test, temperature test and noise test;

[0040] a. Motion performance test: Apply constant load or different loads to the ball screw pair, obtain the actual displacement of the ball screw pair through the linear grating ruler, and calculate the rotation error, transmission efficiency, positioning accuracy and repeatability of the ball screw pair;

[0041] b. Force load test: divided into static load test and dynamic load test; static load test is used to observe the deformation and load-bearing capacity of the ball screw pair, and dynamic load test is used to evaluate the fatigue life and stability of the ball screw pair;

[0042] c. Reliability life test: Conduct long-term cycle tests to simulate the use of ball screw pairs in actual applications, evaluate their life and stability, and predict the remaining life of ball screw pairs;

[0043] d. Vibration test, temperature test and noise test: used to comprehensively evaluate the operating status and reliability of the ball screw pair with multiple indicators;

[0044] T4, stop the test;

[0045] T41. After the test is completed, gradually reduce the load and stop loading the ball screw pair;

[0046] T42, send instructions to the servo motor through the CNC system to stop the ball screw pair drive;

[0047] T43. Turn off the control system of the test bench and ensure that the equipment is in a safe state;

[0048] T44. Check the status of the ball screw pair and the test bench to confirm that there are no abnormalities;

[0049] T5. Experimental data analysis;

[0050] T51. Organize and compile statistics on the data collected during the test;

[0051] T52. Analyze and interpret the data based on the test results to evaluate the performance and life of the ball screw pair;

[0052] T53. Write a test report, summarize the test results and make corresponding recommendations.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] 1. Simulation of real working conditions: The comprehensive performance test device for ball screw pairs that simulates real working conditions is built with machine tool components (test device base and workbench, etc.) that match the ball screw pair test piece. The workbench is used to simulate the inertial load of the ball screw pair during operation. A hydraulic loading system based on electro-hydraulic servo is used for static and dynamic loading. The cutting force amplitude and loading frequency can be dynamically adjusted according to the different working conditions of the ball screw pair, thereby simulating the actual use conditions of the ball screw pair. The test results are closer to the real working conditions.

[0055] 2. Synchronous tracking loading: This ball screw pair comprehensive performance test device that simulates real working conditions uses two ball screw pairs of the same specification for comprehensive performance testing. The two sets of ball screw pairs are driven synchronously, which is manifested as the distance between the loading workbench and the tested workbench remaining basically unchanged. On this basis, simulated axial force loading is carried out, which can realize synchronous loading and tracking loading of the two sets of ball screw pairs at the same time. The loading method is novel and the test efficiency is high.

[0056] 3. Synchronous on-machine testing can be realized: The ball screw pair comprehensive performance test device that simulates real working conditions can simultaneously complete the test and detection of the comprehensive performance of the ball screw pair specimen, without the need to disassemble the ball screw pair specimen for separate testing.

[0057] 4. Strong interchangeability and wide range of applications: The comprehensive performance test device for ball screw pairs that simulates real working conditions can be used to test ball screw pairs of different models. It only requires replacing the fixed support device and the nut seat, which reflects the versatility and flexibility of the test device. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 It is a schematic diagram of the structure of the device of the present invention.

[0059] Figure 2 It is a schematic diagram of the structure of the grating ruler integrated installation unit in the device of the present invention.

[0060] Figure 3 It is a schematic structural diagram of the support driving unit in the device of the present invention.

[0061] Figure 4 It is a schematic diagram of the structure of the axial force simulation loading unit in the device of the present invention.

[0062] Figure 5 Flow chart of the method of the present invention.

[0063] Figure 6 It is the content included in the comprehensive performance detection in the method of the present invention.

[0064] Figure 7 Schematic diagram of the control principle of the device of the present invention.

[0065] In the figure: test device base 1, rolling guide pair 2, grating scale integrated installation unit 3, grating scale installation bracket 301, linear grating scale 302, grating scale guide connecting plate 303, drag chain groove 304, support drive unit 4, fixed support base 401, rear support unit 402, nut seat 403, front support unit 404, coupling 405, servo motor 406, circular grating installation sleeve 407, circular grating 408, motor mounting seat 409, ball screw pair 410, loading workbench 5, axial force simulation loading unit 6, rear L-shaped plate 601, hydraulic cylinder 602, mounting raft plate 603, electro-hydraulic servo valve 604, front L-shaped plate 605, loading connecting plate 606, second connecting rod 607, S-shaped tension and pressure sensor 608, first connecting rod 609, tested workbench 7. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0067] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0068] like Figure 1-Figure 4 As shown, a comprehensive performance test device for a ball screw pair simulating real working conditions provided by an embodiment of the present invention includes a test device base 1, a rolling guide pair 2, a grating ruler integrated installation unit 3, a ball screw pair 410, a support drive unit 4, a loading workbench 5, an axial force simulation loading unit 6, a tested workbench 7 and a comprehensive performance detection unit;

[0069] The test device base 1 is the base of the device;

[0070] The rolling guide pair 2 is installed on the test device base 1 and is used to connect the loading workbench 5 and the tested workbench 7;

[0071] The grating ruler integrated installation unit 3 is fixed on the test device base 1 and connected to the loading workbench 5 and the measured workbench 7, and is used to feed back the absolute positions of the loading workbench 5 and the measured workbench 7 to the numerical control system;

[0072] The ball screw pair 410 includes a ball screw, a screw nut and balls (with or without a cage), which is the test object of the present device, and a working condition simulation is performed on it and a comprehensive performance test study is carried out.

[0073] The support drive unit 4 is used to realize the fixed support and drive of the ball screw pair 410. There are two sets of support drive units 4. The two sets of support drive units 4 are distributed on the test device base 1 in a staggered alignment manner, which can realize the maximum running-in of the ball screw pair 410 and avoid that part of the length of the ball screw pair 410 cannot participate in the test. The two sets of support drive units 4 are respectively connected to the loading workbench 5 and the workbench under test 7. The control system realizes the synchronous drive of the loading workbench 5 and the workbench under test 7 by synchronously controlling the two sets of support drive units 4, providing hardware support for subsequent axial force simulation loading;

[0074] The loading workbench 5 and the tested workbench 7 are both connected to the rolling guide pair 2;

[0075] The axial force simulation loading unit 6 is fixed above the loading workbench 5 and the measured workbench 7 , and connects the loading workbench 5 and the measured workbench 7 .

[0076] The comprehensive performance detection unit includes a positioning accuracy and repeatability detection module, a vibration signal detection module, a temperature detection module and a noise detection module; the positioning accuracy and repeatability detection module is used to calculate the positioning accuracy and repeatability of the ball screw; the vibration signal detection module and the temperature detection module are used to monitor the vibration data and temperature data of the ball screw pair 410; the noise detection module is used to monitor the environmental noise and working noise of the ball screw pair 410.

[0077] like Figure 1As shown, as a preferred embodiment of the present invention, the test device base 1 mainly serves to fix and support the remaining parts of the test device, and is horizontally placed on the concrete surface through anchor bolts. The main installation base surface of other devices on the test device base 1 can be kept horizontal by adjusting the position of the anchor bolts. A T-shaped groove is opened on the upper surface of the test device base 1; a large space is reserved in the rib cavity design part of the test device base 1, which can be used to store test equipment and accessories while being lightweight.

[0078] like Figure 1 As shown, as a preferred embodiment of the present invention, the rolling guide pair 2 is composed of a rolling guide body and a rolling slider, which is installed on the test device base 1 by fixing screws and guide fixing wedges. The lower surfaces of the loading workbench 5 and the tested workbench 7 are each fixed with four rolling sliders, which are arranged in groups of two and are located on the left and right sides of the lower surface, respectively. The rolling sliders (four in total) on the same side of the loading workbench 5 and the tested workbench 7 are slidably connected to a rolling guide body. The rolling guide pair 2 needs to ensure installation requirements such as horizontality and verticality.

[0079] like Figure 1 and Figure 2 As shown, as a preferred embodiment of the present invention, the grating scale integrated installation unit 3 includes a grating scale mounting bracket 301, a linear grating scale 302, a grating scale guide connecting plate 303 and a drag chain slot 304; the grating scale mounting bracket 301 is installed on the surface of the test device base 1, and is fixed with T-nuts in the T-slot on the test device base 1 by screws; the linear grating scale 302 is composed of a grating scale bar and two reading heads, and is connected to the grating scale mounting bracket 301 by screws; the grating scale guide connecting plate 303 is provided with two, which are respectively connected to the two reading heads on the linear grating scale 302 by screws, and the two reading heads are respectively connected to the loading workbench 5 and the measured workbench 7; the drag chain slot 304 is installed on the grating scale mounting bracket 301 by screws, and is used to place the drag chain for easy wiring.

[0080] The linear grating ruler 302 is arranged in a central position to reduce Abbe measurement errors. The test device realizes closed-loop control of the system through real-time monitoring of the linear grating ruler 302 and the encoder.

[0081] like Figure 1 and Figure 3As shown, as a preferred embodiment of the present invention, the support drive unit 4 includes a fixed support base 401, a rear support unit 402, a nut seat 403, a front support unit 404, a coupling 405, a servo motor 406, a circular grating mounting sleeve 407, a circular grating 408 and a motor mounting seat 409; the fixed support base 401 is fixed to the T-nut in the T-slot on the test device base 1 by screws, and the upper surface is used to install the rear support unit 402; the rear support unit 402 and the front support unit 404 are both composed of a fixed support unit body, a fixed support unit gland, an angular contact ball bearing, a locking nut and a bearing retaining ring, which are used to fix and install both ends of the ball screw pair 410, and the rear support unit 402 and the front support unit 404 are respectively mounted on the fixed support base 401 and the motor mounting seat 409 by screws; the nut seat 403 is a non-standard design to facilitate the subsequent replacement of the specifications and models of the ball screw pair 410, and the nut seat 40 3 is used to connect the screw nut in the ball screw pair 410, and on this basis, it is respectively fixed to the loading workbench 5 and the measured workbench 7; the coupling 405 is used to connect the servo motor 406 and the ball screw pair 410; the servo motor 406 is connected to the motor mounting seat 409 by screws, serving as the driving function power source of the ball screw pair 410; the circular grating mounting sleeve 407 is connected to the output shaft of the servo motor 406 by a flat key and a screw limiter; the circular grating 408 includes a grating disk and a reading head, which are respectively connected to the circular grating mounting sleeve 407 and the motor mounting seat 409 by screws, and is used to detect the theoretical rotation angle of the ball screw pair 410; the motor mounting seat 409 is connected to the test device base 1 by screws, and the test device base 1 is redundantly designed for the installation of the motor mounting seat 409, which can realize the conversion between the misalignment alignment mode and the end alignment mode and the conversion of the positions of the two ball screw pairs 410 in the misalignment alignment mode.

[0082] like Figure 1 and Figure 3 As shown, as a preferred embodiment of the present invention, the loading workbench 5 and the workbench under test 7 are used to realize the connection between the linear grating scale 302, the ball screw pair 410 and the axial force simulation loading unit 6. Through the synchronous drive of the ball screw pair 410, the synchronous drive of the loading workbench 5 and the workbench under test 7 can be realized, providing tracking loading conditions for the axial force simulation loading unit 6.

[0083] like Figure 1-Figure 4 As shown, as a preferred embodiment of the present invention, the axial force simulation loading unit 6 realizes static and dynamic simulation loading of the axial force through electro-hydraulic servo control, and the two sets of ball screw pairs 410 are subjected to interaction forces of equal magnitude and opposite directions, and can simultaneously simulate the real working conditions of the two sets of ball screw pairs 410, including loading amplitude and loading frequency, to facilitate comparative analysis and summary.

[0084] The axial force simulation loading unit 6 includes a rear L-shaped plate 601, a hydraulic cylinder 602, a mounting raft plate 603, an electro-hydraulic servo valve 604, a front L-shaped plate 605, a loading connecting plate 606, a second connecting rod 607, an S-shaped tension and pressure sensor 608 and a first connecting rod 609;

[0085] The rear L-shaped plate 601 and the front L-shaped plate 605 are connected to the loading workbench 5 by screws, and are used to install the hydraulic cylinder 602; the hydraulic cylinder 602 includes a front end cover, a rear end cover, a finely ground cylinder barrel, a finely ground electroplated pull rod, a spheroidal graphite piston and a chrome-plated piston rod, and the connection between the rear L-shaped plate 601, the front L-shaped plate 605 and the hydraulic cylinder 602 is achieved by finely ground electroplated pull rods and nuts, which serve as a power source for axial force simulation loading; the mounting raft plate 603 is connected to the front end cover and the rear end cover of the hydraulic cylinder 602 by screws, and is used to install the electro-hydraulic servo valve 604; the electro-hydraulic servo valve 604 is connected to the mounting raft plate 603 by screws, and cooperates with the electro-hydraulic servo in the control system. The servo valve amplifier is used to convert low-power electrical signal input into high-power hydraulic energy (pressure and flow) output, so as to realize the displacement, velocity, acceleration and force control of the hydraulic cylinder 602; the loading connecting plate 606 is installed on the upper surface of the workbench 7 to be tested and is connected to the second connecting rod 607 by means of double nut anti-loosening, which is used for the action and transmission of axial force; the two ends of the S-type tension and pressure sensor 608 are respectively threadedly connected to the first connecting rod 609 and the second connecting rod 607, which are used to measure the magnitude of the tension or pressure output by the hydraulic cylinder 602 and used for force closed-loop control; the first connecting rod 609 is connected to the front end of the chrome-plated piston rod of the hydraulic cylinder 602 by means of threads.

[0086] like Figure 1 and Figure 3As shown, as a preferred embodiment of the present invention, the positioning accuracy and repeat positioning accuracy detection module includes a laser interferometer, which is used to select a combined detection method of a circular grating 408 and a laser interferometer according to the detection accuracy requirements: the laser interferometer needs to be dynamically adjusted according to the placement position of the test bench characteristics, is placed on the ground near the end of the test bench, and is used to detect the actual displacement of the loading workbench 5, and is placed on the ground near the motor end of the test bench, and is used to detect the actual displacement of the workbench 7 under test; the product of the rotation angle and the lead of the ball screw detected by the circular grating 408 is used as the theoretical displacement, and the displacement detected by the laser interferometer is the actual displacement, and the positioning accuracy and repeat positioning accuracy of the ball screw are obtained by calculation, and this method has relatively high accuracy. The vibration signal detection module and the temperature detection module are fixedly installed on the surfaces of the rear support unit 402, the nut seat 403 and the front support unit 404. The vibration signal detection module includes a three-axis acceleration sensor, and the temperature detection module includes a temperature sensor. The three-axis acceleration sensor and the temperature sensor are respectively used to monitor the vibration data and temperature data of the ball screw pair 410; the noise detection module is distributed around the test bench and is one meter apart from the test bench, and is used to monitor the environmental noise and working noise of the ball screw pair 410.

[0087] In the embodiment of the present invention, Figure 7 As shown, the comprehensive performance test device of the ball screw pair simulating the real working condition, when conducting the test, the console is used to send and receive instructions and collect data, specifically including two PLCs respectively sending instructions to the corresponding servo drivers according to the program preset by the console, driving the servo motor 406 to operate; the instructions sent by the console are converted into analog signals by the D / A converter, and then amplified by the electro-hydraulic servo valve amplifier, and enter the electro-hydraulic servo valve 604, so as to control the hydraulic cylinder 602 to realize the variable load loading function; each sensor collects the relevant data of the ball screw pair 410 in real time, such as tension (S-type tension sensor 608), displacement (linear grating ruler 302), vibration (three-axis acceleration sensor), temperature (temperature sensor), etc., the collected analog signals are amplified by the signal amplifier, and then converted into digital signals by the A / D converter and enter the console; the console processes and analyzes these data, so as to evaluate the comprehensive performance of the ball screw pair under the simulated real working condition, such as accuracy, load capacity, dynamic characteristics and temperature characteristics.

[0088] like Figure 5 and Figure 6 As shown, a test method for a ball screw pair comprehensive performance test device simulating real working conditions provided by an embodiment of the present invention includes the following steps:

[0089] T1. Preparation before the test;

[0090] T11. Determine the test object: determine the specification and model of the ball screw pair 410 to be tested, and select a suitable support drive unit 4 for the installation of the ball screw pair 410;

[0091] T12. Install the ball screw pair 410: Install the ball screw pair 410 to be tested on the test device, and use the fixed support method at both ends to install and fix it according to the standard to ensure that the ball screw pair 410 is firmly installed;

[0092] T13. Test bench safety inspection: strictly check whether all working parts of the test bench are locked, check whether the pressure of the hydraulic pump station is within the normal working range, check whether the pressure of the hydraulic cylinder 602 is normal, prevent accidental injury to test personnel after the test starts, and load static force or dynamic force in advance as needed.

[0093] T14. Debug the testing equipment: Check whether the three-axis acceleration sensor and temperature sensor are well pasted and the signal acquisition is normal, turn on the laser interferometer, and adjust the laser interferometer so that it is within the working range.

[0094] T15. Environmental testing and preparation: Ensure that there is no debris near the test bench, the test temperature is within the working range of the test equipment, and there is no sunlight interference on the test device when the test bench is working.

[0095] T2. Turn on the test bench;

[0096] T21. Turn on the power of the test device and ensure that the power supply is stable;

[0097] T22. Start the control system of the test bench, enter the test mode, and set the test parameters as needed, including the driving speed, acceleration, amplitude and frequency of the hydraulic loading, etc.;

[0098] T23. Confirm whether the safety measures of the test bench have been enabled, such as emergency stop button, protective cover, etc.

[0099] T3. Conduct the test;

[0100] T31. Console input loader program spectrum: Use the console input loader program spectrum according to the test requirements to set the operating parameters of the ball screw pair 410, including the speed, load type (static or dynamic), load amplitude and frequency, etc., to ensure that the input parameters meet the test requirements and adjust them as needed;

[0101] T32, servo motor 406 drive start: start servo motor 406, drive ball screw pair 410 to operate, according to the speed requirement set in the loading program spectrum, control the servo system to operate according to the set value. At the same time, the speed, power input and output and other important parameters of ball screw pair 410 are monitored through sensor elements such as encoder or circular grating 408, and the data are recorded for subsequent analysis;

[0102] T33, static and dynamic force loading of hydraulic cylinder 602: according to the load requirements set in the loading program spectrum, the hydraulic cylinder 602 is controlled by the electro-hydraulic servo control system to load the set load, and the force closed-loop control is realized by the S-type tension pressure sensor 608;

[0103] T34, comprehensive performance test: comprehensive performance test mainly includes six parts: motion performance test, force load test, reliability life test, vibration test, temperature test and noise test:

[0104] a. Motion performance test: applying a constant load or different loads to the ball screw pair 410, obtaining the actual displacement of the ball screw pair 410 through the linear grating ruler 302, thereby calculating the rotation error, transmission efficiency, positioning accuracy, and repeatability of the ball screw pair 410;

[0105] b. Force load test: It is divided into static load test and dynamic load test. The static load test is used to observe the deformation and load-bearing capacity of the ball screw pair 410, and the dynamic load test is used to evaluate the fatigue life and stability of the ball screw pair 410;

[0106] c. Reliability life test: a cycle test with a long duration is performed to simulate the use of the ball screw pair 410 in actual applications, evaluate its life and stability, and predict the remaining life of the ball screw pair 410;

[0107] d. Vibration test, temperature test and noise test: used to comprehensively evaluate the operating status and reliability of the ball screw pair 410 with multiple indicators.

[0108] T4, stop the test;

[0109] T41. After the test is completed, gradually reduce the load and stop loading the ball screw pair 410;

[0110] T42, sending a command to the servo motor 406 through the numerical control system to stop the driving of the ball screw pair 410;

[0111] T43. Turn off the control system of the test bench and ensure that the equipment is in a safe state;

[0112] T44. Check the status of ball screw pair 410 and test bench to confirm that there are no abnormalities.

[0113] T5. Experimental data analysis;

[0114] T51. Organize and compile statistics on the data collected during the test;

[0115] T52. Analyze and interpret the data based on the test results to evaluate the performance and life of the ball screw pair 410;

[0116] T53. Write a test report, summarize the test results and make corresponding recommendations.

[0117] The above are only preferred embodiments of the present invention. It should be pointed out that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention. These should also be regarded as the protection scope of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A comprehensive performance test device for a ball screw pair simulating real working conditions, comprising a ball screw pair, wherein the ball screw pair comprises a ball screw, a screw nut and a ball; characterized in that: It also includes a test device base, a rolling guide pair, a grating ruler integrated installation unit, a support drive unit, a loading table, an axial force simulation loading unit, a tested table and a comprehensive performance detection unit; The upper surface of the test device base is provided with a T-shaped groove; The rolling guide pair is installed on the test device base and is used to connect the loading workbench and the tested workbench; The grating ruler integrated installation unit is fixed on the test device base and connected to the loading workbench and the measured workbench, and is used to feed back the absolute positions of the loading workbench and the measured workbench to the numerical control system; The support drive unit is used to realize the fixed support and drive of the ball screw pair. Two sets of support drive units are provided. The two sets of support drive units are distributed on the base of the test device in a staggered alignment manner, and the two sets of support drive units are respectively connected to the loading workbench and the workbench under test. The control system realizes the synchronous drive of the loading workbench and the workbench under test by synchronously controlling the two sets of support drive units. The axial force simulation loading unit is fixed above the loading workbench and the workbench under test, and connects the loading workbench and the workbench under test; the axial force simulation loading unit realizes static and dynamic simulation loading of the axial force through electro-hydraulic servo control; The comprehensive performance detection unit includes a positioning accuracy and repeatability detection module, a vibration signal detection module, a temperature detection module and a noise detection module; the positioning accuracy and repeatability detection module is used to calculate the positioning accuracy and repeatability of the ball screw; the vibration signal detection module and the temperature detection module are used to monitor the vibration data and temperature data of the ball screw pair; the noise detection module is used to monitor the environmental noise and working noise of the ball screw pair.

2. The ball screw pair comprehensive performance test device simulating real working conditions according to claim 1 is characterized in that: The rolling guide pair consists of a rolling guide body and a rolling slider, which is installed on the base of the test device by fixing screws and guide fixing wedges; the lower surfaces of the loading workbench and the tested workbench are each fixed with four rolling sliders, and the rolling sliders are grouped in pairs and are respectively located on the left and right sides of the lower surface, and the rolling sliders of the loading workbench and the tested workbench on the same side are slidably connected to a rolling guide body.

3. The ball screw pair comprehensive performance test device simulating real working conditions according to claim 1 is characterized in that: The grating ruler integrated installation unit includes a grating ruler installation bracket, a linear grating ruler, a grating ruler guide connecting plate and a drag chain slot; The grating scale mounting bracket is installed on the surface of the test device base and is fixed to the T-nut in the T-slot on the test device base by screws; the linear grating scale consists of a grating scale bar and two reading heads, and is connected to the grating scale mounting bracket by screws; the grating scale guide connecting plates are provided with two, which are respectively connected to the two reading heads on the linear grating scale by screws, and the two reading heads are respectively connected to the loading workbench and the measured workbench; the drag chain slot is installed on the grating scale mounting bracket by screws and is used to place the drag chain.

4. The ball screw pair comprehensive performance test device simulating real working conditions according to claim 3 is characterized in that: The linear grating ruler is arranged in a central manner to reduce Abbe measurement errors.

5. The ball screw pair comprehensive performance test device simulating real working conditions according to claim 1 is characterized in that: The support drive unit includes a fixed support base, a rear support unit, a nut seat, a front support unit, a coupling, a servo motor, a circular grating mounting sleeve, a circular grating and a motor mounting seat; The fixed supporting base is fixed to the T-nut in the T-slot on the base of the test device by screws, and the upper surface is used to install the rear supporting unit; the rear supporting unit and the front supporting unit are used to fix the two ends of the ball screw pair, and the rear supporting unit and the front supporting unit are respectively installed on the fixed supporting base and the motor mounting seat by screws; the nut seat is used to connect the screw nut in the ball screw pair, and is respectively fixed to the loading workbench and the measured workbench; the coupling is used to connect the servo motor and the ball screw pair; the servo motor is connected to the motor mounting seat by screws, and serves as the driving function power source of the ball screw pair; the circular grating mounting sleeve is connected to the output shaft of the servo motor by a flat key and a screw limiter; the circular grating includes a grating disk and a reading head, which are respectively connected to the circular grating mounting sleeve and the motor mounting seat by screws, and are used to detect the theoretical rotation angle of the ball screw pair; the motor mounting seat is connected to the base of the test device by screws.

6. The ball screw pair comprehensive performance test device simulating real working conditions according to claim 3 is characterized in that: The loading workbench and the measured workbench are used to realize the connection between the linear grating ruler, the ball screw pair and the axial force simulation loading unit.

7. The ball screw pair comprehensive performance test device simulating real working conditions according to claim 1 is characterized in that: The axial force simulation loading unit comprises a rear L-shaped plate, a hydraulic cylinder, a mounting raft plate, an electro-hydraulic servo valve, a front L-shaped plate, a loading connecting plate, a second connecting rod, an S-shaped tension and pressure sensor and a first connecting rod; The rear L-shaped plate and the front L-shaped plate are connected to the loading workbench by screws and are used to install the hydraulic cylinder; the hydraulic cylinder serves as a power source for axial force simulation loading; the mounting raft is connected to the hydraulic cylinder by screws and is used to install the electro-hydraulic servo valve; the electro-hydraulic servo valve is connected to the mounting raft by screws, and cooperates with the electro-hydraulic servo valve amplifier in the control system to convert low-power electrical signal input into high-power hydraulic energy output, thereby realizing the displacement, speed, acceleration and force control of the hydraulic cylinder; the loading connecting plate is installed on the upper surface of the workbench to be tested and is connected to the second connecting rod by a double nut anti-loosening method, for the action and transmission of axial force; the two ends of the S-shaped tension and pressure sensor are respectively threadedly connected to the first connecting rod and the second connecting rod, for measuring the magnitude of the tension or pressure output by the hydraulic cylinder and for force closed-loop control; the first connecting rod is connected to the hydraulic cylinder by threads.

8. The ball screw pair comprehensive performance test device simulating real working conditions according to claim 5 is characterized in that: The positioning accuracy and repeat positioning accuracy detection module includes a laser interferometer, which is used to determine the combined detection method of the circular grating and the laser interferometer. The product of the rotation angle and the lead of the ball screw detected by the circular grating is used as the theoretical displacement, and the displacement detected by the laser interferometer is the actual displacement; the vibration signal detection module and the temperature detection module are fixedly installed on the surfaces of the rear support unit, the nut seat and the front support unit. The vibration signal detection module includes a three-axis acceleration sensor, and the temperature detection module includes a temperature sensor. The three-axis acceleration sensor and the temperature sensor are used to monitor the vibration data and temperature data of the ball screw pair respectively; the noise detection modules are distributed around the test bench and are one meter apart from the test bench.

9. A test method for a ball screw pair comprehensive performance test device simulating real working conditions according to any one of claims 1 to 8, characterized in that: The following steps are involved: T1. Preparation before the test; T11. Determine the test object: determine the specifications and model of the ball screw pair to be tested, and select a suitable support drive unit; T12. Install the ball screw pair: Install the ball screw pair to be tested on the test device; T13. Test bench safety inspection: Check the locking condition of the test bench components, and the pressure of the hydraulic pump station and hydraulic cylinder; T14. Debugging and testing equipment: Check the pasting and signal collection of the three-axis acceleration sensor and temperature sensor. After confirming that they are correct, turn on the laser interferometer and adjust the laser interferometer so that it is within the working range; T15. Environmental testing and preparation: Ensure that the test environment is clean, the temperature is appropriate, and there is no sunlight interference; T2. Turn on the test bench; T21. Turn on the power of the test device; T22, start the control system of the test bench, enter the test mode, and set the test parameters, including the driving speed, acceleration, and amplitude and frequency of the hydraulic loading; T23. Confirm that the safety measures of the test bench have been activated; T3. Conduct the test; T31, Console input loader program spectrum: Use the console input loader program spectrum to set the operating parameters of the ball screw pair, including speed, load type, load amplitude and frequency; T32, servo motor drive start: start the servo motor to drive the ball screw pair to operate, and control the servo system to run according to the speed requirements set in the loading program spectrum; at the same time, monitor the speed, power input and output of the ball screw pair through the encoder or circular grating, and record the data; T33, static and dynamic force loading of hydraulic cylinder: according to the load requirements set in the loading program spectrum, the hydraulic cylinder is controlled by the electro-hydraulic servo control system to load the set load, and the force closed-loop control is achieved through the S-type tension and pressure sensor; T34, comprehensive performance testing: including motion performance test, force load test, reliability life test, vibration test, temperature test and noise test; a. Motion performance test: Apply constant load or different loads to the ball screw pair, obtain the actual displacement of the ball screw pair through the linear grating ruler, and calculate the rotation error, transmission efficiency, positioning accuracy and repeatability of the ball screw pair; b. Force load test: divided into static load test and dynamic load test; static load test is used to observe the deformation and load-bearing capacity of the ball screw pair, and dynamic load test is used to evaluate the fatigue life and stability of the ball screw pair; c. Reliability life test: Conduct long-term cycle tests to simulate the use of ball screw pairs in actual applications, evaluate their life and stability, and predict the remaining life of ball screw pairs; d. Vibration test, temperature test and noise test: used to comprehensively evaluate the operating status and reliability of the ball screw pair with multiple indicators; T4, stop the test; T41. After the test is completed, gradually reduce the load and stop loading the ball screw pair; T42, send instructions to the servo motor through the CNC system to stop the ball screw pair drive; T43. Turn off the control system of the test bench and ensure that the equipment is in a safe state; T44. Check the status of the ball screw pair and the test bench to confirm that there are no abnormalities; T5. Experimental data analysis; T51. Organize and compile statistics on the data collected during the test; T52. Analyze and interpret the data based on the test results to evaluate the performance and life of the ball screw pair; T53. Write a test report, summarize the test results and make corresponding recommendations.

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