Ball screw pair loading test device

Abstract

The invention discloses a ball screw pair loading test device, and relates to the technical field of ball screw testing. The driving piece is used for driving the tested lead screw to rotate and adopts an integrated headstock structure integrated at one end of the bed body; and the loading piece is used for providing an axial load for the tested lead screw, adopts a dual-motor top-to-top loading structure arranged at the other end of the bed body, and is matched with the integrated headstock structure to form a unified mechanical standard. According to the invention, an integrated headstock structure of the driving piece and a dual-motor opposite-top loading structure of the loading piece are matched to form a unified mechanical standard, a friction torque measurement state and an axial force measurement state are rapidly switched through a switchable connection structure, a to-be-tested lead screw only needs to be clamped once, multi-parameter test can be completed, the test efficiency is effectively improved, and the test cost is reduced. And meanwhile, positioning errors caused by multiple times of clamping are avoided, it is ensured that all parameters are based on the same reference, and data relevance is higher.

Description

Technical Field

[0001] The invention relates to the technical field of ball screw testing, in particular to a ball screw pair loading test device. Background Art

[0002] As a core transmission component in high-precision industrial fields such as mechanical equipment, precision CNC machining centers, and aerospace, the reliability and precision stability of the screw pair's performance have a key impact on the overall processing accuracy and service life of high-end equipment. The screw pair is mainly composed of components such as nuts, balls, screws and inverters. Its overall structural design is aimed at efficiently and accurately converting rotational motion into linear motion, with high load-bearing capacity and excellent transmission efficiency. Depending on the motion cycle mode and pre-tightening method, the screw pair can be divided into various types to meet the technical requirements of different application scenarios, showing strong adaptability and versatility. With its high precision, durability and excellent control characteristics, the screw pair has been widely used in high-end fields such as precision machining, automated manufacturing and aerospace, becoming one of the key functional components.

[0003] In recent years, due to its excellent transmission performance, the screw pair has been widely used in CNC machining centers, aerospace and other industrial fields with extremely high precision requirements. With the continuous expansion of the scope of application, the industry has put forward higher standards for the accuracy, reliability and long-term operation stability of the screw pair. In order to meet the growing demand for performance assurance, the development of a loading test device that integrates loading functions and intelligent online monitoring has become an urgent need. Among them, intelligent online monitoring technology, as one of the core functions of the device, can monitor the key performance parameters of the screw pair, such as stroke error, friction torque, contact stiffness and temperature, without disassembling the screw pair, effectively avoiding the potential damage caused by frequent disassembly and assembly in traditional testing methods. Online monitoring significantly improves the test efficiency and provides a reliable basis for the performance evaluation and life prediction of the screw pair under complex working conditions.

[0004] However, traditional ball screw testing requires multiple clamping, which involves clamping once to measure the stroke error, disassembling and reinstalling to measure the friction torque, and then reinstalling to measure the contact stiffness. Multiple clamping is not only time-consuming, but also leads to poor parameter correlation due to positioning deviation. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the present invention provides a ball screw pair loading test device.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows:

[0007] A ball screw pair loading test device, comprising:

[0008] Bed;

[0009] A driving member for driving the measured lead screw to rotate, which adopts an integrated headstock structure integrated at one end of the bed;

[0010] The loading component is used to provide axial load to the screw being tested. It adopts a dual-motor top loading structure set at the other end of the bed and cooperates with the integrated headstock structure to form a unified mechanical standard;

[0011] A workbench slidably arranged on the bed for mounting a nut of the lead screw to be measured;

[0012] The measuring assembly is integrated on the bed and includes:

[0013] A long grating is set on the bed and the reading head is connected to the workbench, which is used to measure the actual moving distance of the nut of the measured lead screw;

[0014] The circular grating is set at the end of the measured screw shaft, which is used to measure the actual rotation angle of the measured screw to provide a theoretical displacement basis without transmission chain error;

[0015] A digital micrometer that can be magnetically mounted on the surface of the screw being measured, and is used to measure the absolute micro displacement of the nut with the screw being measured as a reference;

[0016] The six-dimensional tension-compression-torsion combination sensor, which is mounted on a workbench and connected to the nut via a switchable connection structure, is configured as follows based on the measured lead screw that is clamped once:

[0017] The stroke error is calibrated collaboratively based on the theoretical displacement basis and the actual movement distance of the nut;

[0018] Switching to a friction torque measurement state through a switchable connection structure to measure the friction torque;

[0019] The switchable connection structure switches to the axial force measurement state, and the contact stiffness is calculated based on the absolute micro-displacement of the nut.

[0020] By real-time monitoring of axial tension, pressure and torque changes, the driving part speed and loading part torque output are dynamically adjusted. Based on unified mechanical standards, multi-parameter integrated online measurement is achieved in a single clamping state.

[0021] Preferably, the switchable connection structure includes a mounting bolt for rigidly connecting the measuring end of the six-dimensional tension-compression-torsion combination sensor to the nut of the measured lead screw, a sensor bolt for rigidly connecting the six-dimensional tension-compression-torsion combination sensor to the workbench, and an end cover bolt for fixing the tail end cover of the six-dimensional tension-compression-torsion combination sensor;

[0022] By tightening or loosening the sensor bolts, mounting bolts and end cover bolts, the axial force measurement state and the friction torque measurement state can be switched.

[0023] Preferably, the driving member includes a driving motor and an integrated head frame, and the integrated head frame is a single rigid body structure, and integrates a mounting seat of the driving motor and a bearing seat for supporting the measured lead screw.

[0024] Preferably, the dual-motor top loading structure includes loading screws symmetrically arranged on both sides of the measured screw, a loading motor, a synchronous transmission mechanism and a tensioning wheel mechanism, and the loading motor synchronously drives the two loading screws to rotate through the synchronous transmission mechanism.

[0025] Preferably, the installation structure of the circular grating includes a transfer tool installed on the end face of the integrated head frame, and a screw chuck tool for seamlessly connecting the end of the measured screw to the transfer tool.

[0026] Preferably, the digital micrometer is fixed to the optical axis surface of the measured lead screw by adsorption through a magnetic base, and its measuring needle is vertically pressed against the flange end face of the nut of the measured lead screw.

[0027] Preferably, a limit bracket is provided on the bed, and a mechanical limit sensor and a zero position sensor are also provided on one side of the workbench, which are respectively used to achieve over-travel protection for the workbench and accurate calibration of the initial position.

[0028] Preferably, the measuring assembly also includes a plurality of temperature sensors driven by a cylinder. After the driving motor and the loading motor stop running, the temperature sensors are driven by the cylinder to automatically adhere to the head, middle and tail surfaces of the measured screw to perform temperature measurement.

[0029] Preferably, the synchronous transmission mechanism includes a synchronous belt and four synchronous wheels, two of which are respectively installed on the synchronous wheel shafts, and the other two synchronous wheels are installed at the tail ends of the two loading screws to ensure the synchronous loading operation of the double screws.

[0030] Preferably, the tensioning wheel mechanism includes a tensioning wheel that is arranged in close contact with the synchronous belt, and the tensioning wheel is adjusted in the vertical direction to keep the synchronous belt in a tensioned state.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The present invention forms a unified mechanical standard through the coordination of the one-piece headstock structure of the driving part and the dual-motor top loading structure of the loading part. Both are integrated into the bed body, which effectively avoids the problem of non-concentricity between the driving axis and the loading axis caused by the independent installation of the traditional split headstock and loading frame, reduces the system errors such as transmission chain offset and loading force eccentricity from the source, thereby improving the measurement accuracy. Through the switchable connection structure, the friction torque measurement state and the axial force measurement state are quickly switched without disassembling the measured screw, and full coverage is achieved in one clamping. The measured screw only needs to be clamped once to complete the three core parameter tests of stroke error calibration, friction torque measurement and contact stiffness calculation, effectively improving the test efficiency and avoiding the positioning error of multiple clamping at the same time, ensuring that each parameter is based on the same benchmark and the data correlation is stronger. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The disclosure of the present invention is described with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. In the drawings, the same reference numerals are used to refer to the same components. Among them:

[0034] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0035] Figure 2 It is a schematic diagram of the bed structure of the present invention;

[0036] Figure 3 It is a structural schematic diagram of the driving member of the present invention;

[0037] Figure 4 It is a structural schematic diagram of the loading component of the present invention;

[0038] Figure 5 Schematic diagram of the position structure of the circular grating of the present invention;

[0039] Figure 6 Schematic diagram of the position structure of the long grating of the present invention;

[0040] Figure 7 This is a schematic diagram of the switchable connection structure of the present invention;

[0041] Figure 8 It is a schematic diagram of the position structure of the digital display dial indicator of the present invention;

[0042] Figure 9 This is a schematic diagram of the position structure of the double-rod telescopic cylinder of the present invention;

[0043] Figure 10 This is a schematic diagram of the temperature sensor position structure of the present invention.

[0044] Explanations in the figure: 1. Bed; 2. Drive motor; 3. Loading motor; 4. Workbench; 5. Circular grating; 6. Long grating; 7. Six-dimensional tension-compression-torsion combination sensor; 8. Integrated headstock; 9. Mechanical limit sensor; 10. Zero position sensor; 11. Digital micrometer; 12. Temperature sensor; 13. Double-rod telescopic cylinder; 14. Limit bracket; 15. Drag chain; 16. Tensioner; 17. Synchronous belt; 18. Synchronous pulley; 19. First locking nut; 20. Second locking nut; 21. Mounting bolt; 22. End cover bolt. DETAILED DESCRIPTION

[0045] It is easy to understand that according to the technical solution of the present invention, without changing the essential spirit of the present invention, a person skilled in the art can propose a variety of interchangeable structural modes and implementation modes. Therefore, the following specific embodiments and drawings are only exemplary descriptions of the technical solution of the present invention and should not be regarded as the entire invention or as a limitation or restriction of the technical solution of the present invention.

[0046] like Figure 1 As shown, a ball screw pair loading test device includes:

[0047] Bed 1;

[0048] A driving member for driving the measured lead screw to rotate, which adopts an integrated headstock structure integrated at one end of the bed 1;

[0049] A loading component for providing an axial load to the screw being tested, which adopts a dual-motor top loading structure provided at the other end of the bed 1 and cooperates with the integrated headstock structure to form a unified mechanical standard;

[0050] A workbench 4 is slidably arranged on the bed 1 for mounting a nut of the lead screw to be measured;

[0051] The measuring assembly integrated on the bed 1 includes:

[0052] A long grating 6 is provided on the bed 1 and the reading head is connected to the workbench 4, which is used to measure the actual moving distance of the nut of the measured lead screw;

[0053] The circular grating 5 is set at the end of the measured screw shaft, which is used to measure the actual rotation angle of the measured screw to provide a theoretical displacement basis without transmission chain error;

[0054] A digital micrometer 11 that can be magnetically mounted on the surface of the screw being measured and is used to measure the absolute micro displacement of the nut with the screw being measured as a reference;

[0055] The six-dimensional tension-compression-torsion combined sensor 7, which is mounted on the workbench 4 and connected to the nut via a switchable connection structure, is configured as follows based on the measured lead screw that is clamped once:

[0056] The stroke error is calibrated collaboratively based on the theoretical displacement basis and the actual movement distance of the nut;

[0057] Switching to a friction torque measurement state through a switchable connection structure to measure the friction torque;

[0058] The switchable connection structure switches to the axial force measurement state, and the contact stiffness is calculated based on the absolute micro-displacement of the nut.

[0059] By real-time monitoring of axial tension, pressure and torque changes, the driving part speed and loading part torque output are dynamically adjusted. Based on unified mechanical standards, multi-parameter integrated online measurement is achieved in a single clamping state.

[0060] Specifically, during measurement, the measured screw is passed through the nut installed on the workbench 4 and the workbench 4 and installed between the driving part and the loading part, and the axial end of the measured screw on the loading part side is tightened by the first locking nut 19 to prevent the measured screw from axial movement. The nut of the measured screw is fixed on the six-dimensional tension, compression and torsion combination sensor 7, so that the axial tension, pressure and torque changes are monitored in real time by the six-dimensional tension, compression and torsion combination sensor 7. The control system accurately controls the rotation speed of the driving part and the torque output of the loading part based on the feedback of the axial tension, pressure and torque monitored in real time by the six-dimensional tension, compression and torsion combination sensor 7, thereby achieving precise control of the movement speed and loading force, thereby ensuring that the test process is carried out stably according to the preset working conditions.

[0061] Furthermore, three main mounting grooves are provided on the top of the bed 1: a V-shaped slide rail groove, a T-shaped groove in the middle, and two linear guide rail mounting grooves symmetrically arranged on both sides of the T-shaped groove. Among them, the V-shaped slide rail groove is used to provide a high-precision sliding guide function for the tail frame of the driving part, and a T-shaped nut is embedded in the T-shaped groove for positioning and locking the tail frame. The two linear guide rail mounting grooves are used to install linear guides, which are used to support and guide the workbench 4 to move precisely along the bed 1. A drag chain groove is provided on one side surface of the bed 1, and the drag chain 15 is placed in the drag chain groove to accommodate and guide the orderly movement of cables and air pipes.

[0062] Furthermore, after the screw under test is installed, various parameters are measured:

[0063] When measuring the stroke error, the control system monitors and feedbacks the test speed, effective stroke and other parameters required for the test stroke error in real time based on the six-dimensional tension, compression and torsion combination sensor 7. The driving part drives the measured screw to rotate. Since the nut of the measured screw is connected to the workbench 4, the actual moving distance of the nut of the measured screw can be reflected by the moving distance of the workbench 4. In order to ensure the accuracy of the stroke error test, the actual moving distance of the nut is measured by the long grating 6 installed on the top of the bed 1 and the reading head set on the workbench 4 through the first fixed plate. The theoretical moving distance of the nut of the measured screw is measured by the circular grating 5 installed on the integrated headstock structure. Since the circular grating 5 is directly set at the end of the measured screw shaft, the actual rotation angle of the screw is measured. Since the transmission chain of the driving part is skipped, the rotation of the screw itself is directly used as the reference, thereby providing a theoretical displacement basis without transmission chain error. By comparing the theoretical moving distance of the nut with the actual moving distance of the nut, the stroke error of the screw pair is accurately calculated.

[0064] When measuring the friction torque, the control system sets the test speed, effective stroke and other parameters required for the test stroke error based on the real-time monitoring feedback of the six-dimensional tension-compression-torsion combination sensor 7, and then forms a gap between the contact surface of the six-dimensional tension-compression-torsion combination sensor 7 and the workbench 4 through a switchable connection structure to achieve mechanical isolation, so that the six-dimensional tension-compression-torsion combination sensor 7 is switched to the friction torque measurement state, and the measured screw is driven by the driving member to rotate in an unloaded state. During the rotation, the friction torque is directly measured by the six-dimensional tension-compression-torsion combination sensor 7.

[0065] When measuring contact stiffness, the nut to be measured is rigidly connected to the workbench 4 to prevent it from rotating. The digital micrometer 11 is adsorbed on the surface of the screw to be measured. The six-dimensional tension, compression and torsion combination sensor 7 is fixed to the workbench 4 through a switchable connection structure to switch to the axial force measurement state. The control system controls the driving part to stop running, and the loading part applies an axial load to the screw to be measured. During the loading process, the six-dimensional tension, compression and torsion combination sensor 7 collects the axial force signal in real time, and by adjusting the output torque of the loading motor, ensures that the loading process meets the force value requirements set in the test. The digital micrometer 11 synchronously monitors the absolute micro displacement of the nut of the measured screw relative to the measured screw. The contact stiffness of the measured screw can be obtained through the corresponding relationship between the axial loading force and the absolute micro displacement. Compared with the traditional single-motor loading, the dual-motor top loading structure of the loader can offset the lateral force in the loading process through the torque of the two motors, making the axial load more uniform and stable, and the loading range wider. The axial force output of different magnitudes can be achieved through the motor torque adjustment, which effectively avoids the micro deformation of the bed or the loading force fluctuation caused by the reaction force during single-motor loading.

[0066] Furthermore, since traditional ball screw tests require multiple clamping, clamping once to measure the stroke error, disassembly and reinstallation to measure the friction torque, and then reinstallation to measure the contact stiffness, multiple clamping is not only time-consuming, but also leads to poor parameter correlation due to positioning deviation. A unified mechanical standard is formed by cooperating the integrated headstock structure of the driving part and the dual-motor top loading structure of the loading part. Both are integrated into the bed 1, which effectively avoids the problem of non-concentricity between the driving axis and the loading axis caused by independent installation of the traditional split headstock and loading frame, reduces system errors such as transmission chain offset and loading force eccentricity from the source, thereby improving the measurement accuracy. Through the switchable connection structure, the friction torque measurement state and the axial force measurement state can be quickly switched without disassembling the measured screw, achieving full coverage in one clamping. The measured screw only needs to be clamped once to complete the three core parameter tests of stroke error calibration, friction torque measurement and contact stiffness calculation, effectively improving the test efficiency, while avoiding the positioning error of multiple clamping, ensuring that each parameter is based on the same benchmark, and the data correlation is stronger.

[0067] The switchable connection structure includes a mounting bolt 21 for rigidly connecting the measuring end of the six-dimensional tension-compression-torsion combination sensor 7 to the nut of the measured lead screw, a sensor bolt for rigidly connecting the six-dimensional tension-compression-torsion combination sensor 7 to the workbench 4, and an end cover bolt 22 for fixing the tail end cover of the six-dimensional tension-compression-torsion combination sensor 7;

[0068] By tightening or loosening the sensor bolt, the mounting bolt 21 and the end cover bolt 22, the switching between the axial force measurement state and the friction torque measurement state is achieved.

[0069] Specifically, a sensor end cover is provided at the tail of the six-dimensional tension, compression and torsion combination sensor 7. When measuring the axial force, the nut of the measured screw is rigidly connected to the measuring end of the six-dimensional tension, compression and torsion combination sensor 7 through the mounting bolt 21, and the sensor bolt is tightened. At the same time, the end cover bolt 22 is loosened to separate the end cover at the tail of the six-dimensional tension, compression and torsion combination sensor 7 from the workbench, thereby ensuring that the sensor can freely respond to axial force and accurately measure the axial tension and pressure of the measured screw pair.

[0070] Furthermore, when conducting a friction torque test, the sensor bolt is loosened and the end cover bolt 22 is tightened at the same time, thereby pushing open the connection between the six-dimensional tension-compression-torsion combination sensor 7 and the workbench 4. When the measured screw rotates to measure the friction torque, the end cover bolt 22 plays an anti-rotation role, thereby achieving the effect of measuring the friction torque.

[0071] The driving component includes a driving motor 2 and an integrated head frame 8. The integrated head frame 8 is a single rigid body structure, and integrates the mounting seat of the driving motor 2, the bearing seat for supporting the measured lead screw, and the guide rail connected to the bed body 1.

[0072] Specifically, the two ends of the measured screw are respectively fixedly mounted on the integrated headstock 8 and the tailstock, one end of the measured screw is fixed to the tailstock by a first locking nut 19, the drive motor 2 is fixed in the integrated headstock 8, and is connected to the connecting shaft through the output end coupling of the drive motor 2, and then connected to the shaft end of the screw through the coupling at the end of the measured screw, thereby realizing the direct drive rotation of the measured screw by the drive motor 2.

[0073] The dual-motor top loading structure includes loading screws symmetrically arranged on both sides of the measured screw, a loading motor 3, a synchronous transmission mechanism and a tensioning wheel mechanism. The loading motor 3 drives the two loading screws to rotate synchronously through the synchronous transmission mechanism.

[0074] Specifically, the shaft ends of the two loading screws are respectively installed between the integrated headstock 8 and the tailstock of the loading screw through thrust combination bearings. The nut end of the loading screw is fixedly connected to the workbench 4. In order to prevent axial movement of the loading screw, the shaft end of the loading screw is positioned and tightened by a second locking nut 20. At the same time, a loading screw shaft end support seat is added at the tail end of the loading screw to increase the support stiffness of the tail end of the loading screw and ensure stability during the loading process.

[0075] Furthermore, when performing stroke error measurement and friction torque measurement, in order to ensure the accuracy of the stroke error test, the nuts of the loading screws on both sides are disengaged from the workbench 4 during measurement. To ensure the accuracy of the friction torque measurement, the nuts of the loading screws are disengaged from the workbench 4 to avoid interference of the loading force on the test results.

[0076] The mounting structure of the circular grating 5 includes a transfer fixture mounted on the end face of the integrated headstock 8 via a cross roller shaft, and a lead screw chuck fixture for seamlessly connecting the end of the lead screw to be measured with the transfer fixture.

[0077] Specifically, in order to ensure the installation accuracy of the measured screw, one end of the measured screw is fixed in a reference sleeve installed on the integrated head frame 8, the adapter plate is connected to the reference sleeve, and a support unit is installed on the adapter plate to support the free end of the measured screw. The circular grating 5 is installed on the cross roller bearing on the end face of the integrated head frame 8 through the adapter tooling. The screw chuck tooling clamps the measured screw and is connected to the dial shaft on the adapter tooling. When the measured screw rotates, the circular grating 5 is driven to rotate synchronously. The reading head of the circular grating 5 is fixed to the upper part of the integrated head frame 8, and cooperates with the circular grating 5 through the reading head fixing plate to record the actual number of rotations of the measured screw in real time. Combined with the screw lead and the number of rotations, the theoretical moving distance of the nut can be obtained. In this way, the circular grating 5 is installed on the side of the measured screw, which effectively avoids the measurement error introduced by the coupling gap and ensures the accuracy of the measurement results.

[0078] The digital display micrometer 11 is fixed to the optical axis surface of the measured lead screw by adsorption through a magnetic base, and its measuring needle is vertically pressed against the flange end face of the nut of the measured lead screw.

[0079] Specifically, the digital micrometer 11 is installed magnetically and directly measures the absolute micro-displacement of the nut based on the surface of the measured screw. Compared with the traditional measurement method based on the bed as the reference, it eliminates the interference of the bed's own deformation and the working platform sliding gap on the micro-displacement measurement. It is particularly suitable for the precise capture of micron-level displacement in contact stiffness calculations, further improving the measurement accuracy.

[0080] A limit bracket 14 is provided on the bed 1, and a mechanical limit sensor 9 and a zero position sensor 10 are also provided on one side of the workbench 4, which are respectively used to realize over-travel protection of the workbench 4 and accurate calibration of the initial position.

[0081] Specifically, when the workbench 4 moves to the zero position sensor 10, the zero position sensor 10 is triggered to calibrate the initial position. According to the effective stroke of the measured screw, the mechanical limit sensors 9 on both sides are adjusted to reasonable positions to ensure that the workbench 4 does not exceed the safe stroke during movement. When the workbench 4 moves to the dangerous edge position, the limit bracket 14 fixed on the bed 1 will enter the sensing range of the mechanical limit sensor 9, triggering the limit, and the control system will immediately stop the motor operation to ensure safety.

[0082] The measuring assembly also includes multiple temperature sensors 12 driven by cylinders. After the driving motor 2 and the loading motor 3 stop running, the temperature sensors 12 are driven by the cylinders to automatically adhere to the head, middle and tail surfaces of the measured screw to measure the temperature.

[0083] Specifically, a double-rod telescopic cylinder 13 is installed on the side of the integrated headstock 8, and the tail of the telescopic rod is connected to another double-rod telescopic cylinder 13 through a first cylinder fixing plate. A temperature sensor probe fixing plate is installed at the tail of the telescopic rod of the other double-rod telescopic cylinder 13, and a temperature sensor 12 is installed on the temperature sensor probe fixing plate. The temperature sensor probe fixing plate adopts a waist-shaped hole design, which is convenient for fine-tuning the temperature sensor 12 in the axial direction, so that the temperature sensor 12 avoids the raceway and is close to the surface of the measured screw, thereby realizing accurate measurement of the temperature of the head of the measured screw. The third double-rod telescopic cylinder 13 is installed on the workbench 4 through the second cylinder fixing plate, and a second temperature sensor 12 is set at the tail of the telescopic rod of the third double-rod telescopic cylinder 13 for measuring the temperature in the middle of the measured screw. The third double-rod telescopic cylinder 13 is installed on the tailstock through the third cylinder fixing plate. There are four double-rod telescopic cylinders 13, and the third temperature sensor 12 is configured at the tail of the fourth double-rod telescopic cylinder 13, which is used to collect the temperature of the tail of the screw. The control system stops the operation of the drive motor 2 and the loading motor 3 to ensure the stability of the measurement process and operational safety. Subsequently, the control system executes the temperature measurement instruction and controls the double-rod telescopic cylinders 13 to extend in sequence, so that the temperature sensors 12 are successively attached to the surface of the measured screw. The attachment time of each temperature sensor 12 at the head, middle and tail of the screw is about 5 seconds to ensure the accuracy of the measurement data. After the measurement is completed, the double-rod telescopic cylinder 13 automatically retracts, and the temperature sensor 12 is separated from the surface of the measured screw. The entire temperature measurement process is automatically controlled by the control system, which has the characteristics of simple operation, high efficiency, and reliable data, and can realize the accurate acquisition of the temperature of multiple positions of the measured screw.

[0084] The synchronous transmission mechanism includes a synchronous belt 17 and four synchronous wheels 18, two of which are mounted on synchronous wheel shafts, and the other two synchronous wheels 18 are mounted on the tail ends of the two loading screws to ensure synchronous loading and operation of the double screws.

[0085] Specifically, the loading motor 3 is installed on the loading motor seat, and its output shaft is connected to the synchronous wheel shaft through a coupling. The synchronous wheel shaft is fixed above the loading motor seat through the bearing seats on both sides. Two synchronous belts 17 are respectively connected to the synchronous wheel shaft and the synchronous wheel 18 on the tail end of the loading screw to ensure the synchronous loading operation of the double loading screws.

[0086] The tensioning wheel mechanism includes a tensioning wheel 16 that is arranged in contact with the synchronous belt 17. The tensioning wheel 16 is adjusted in the vertical direction to keep the synchronous belt 17 in a tensioned state.

[0087] Specifically, in order to keep the synchronous belt 17 in a tensioned state, a tensioning pulley 16 is provided on one side of the synchronous belt 17, which is installed on an adjustable tensioning support and can be adjusted in the vertical direction, thereby effectively eliminating the slack and vibration that may occur during the operation of the synchronous belt 17 and improving the stability and reliability of the loading system.

[0088] The technical scope of the present invention is not limited to the contents of the above description. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical idea of ​​the present invention, and these deformations and modifications should all fall within the protection scope of the present invention.

Claims

1. A ball screw pair loading test device, characterized in that: include: Bed; A driving member for driving the measured lead screw to rotate, which adopts an integrated headstock structure integrated at one end of the bed; The loading component is used to provide axial load to the screw being tested. It adopts a dual-motor top loading structure set at the other end of the bed and cooperates with the integrated headstock structure to form a unified mechanical standard; A workbench slidably arranged on the bed for mounting a nut of the lead screw to be measured; The measuring assembly is integrated on the bed and includes: A long grating is set on the bed and the reading head is connected to the workbench, which is used to measure the actual moving distance of the nut of the measured lead screw; The circular grating is set at the end of the measured screw shaft, which is used to measure the actual rotation angle of the measured screw to provide a theoretical displacement basis without transmission chain error; A digital micrometer that can be magnetically mounted on the surface of the screw being measured, and is used to measure the absolute micro displacement of the nut with the screw being measured as a reference; The six-dimensional tension-compression-torsion combination sensor, which is mounted on a workbench and connected to the nut via a switchable connection structure, is configured as follows based on the measured lead screw that is clamped once: The stroke error is calibrated collaboratively based on the theoretical displacement basis and the actual movement distance of the nut; Switching to a friction torque measurement state through a switchable connection structure to measure the friction torque; The switchable connection structure switches to the axial force measurement state, and the contact stiffness is calculated based on the absolute micro-displacement of the nut. By real-time monitoring of axial tension, pressure and torque changes, the driving part speed and loading part torque output are dynamically adjusted. Based on unified mechanical standards, multi-parameter integrated online measurement is achieved in a single clamping state.

2. A ball screw pair loading test device according to claim 1, characterized in that: The switchable connection structure includes a mounting bolt for rigidly connecting the measuring end of the six-dimensional tension-compression-torsion combination sensor to the nut of the measured lead screw, a sensor bolt for rigidly connecting the six-dimensional tension-compression-torsion combination sensor to the workbench, and an end cover bolt for fixing the tail end cover of the six-dimensional tension-compression-torsion combination sensor; By tightening or loosening the sensor bolts, mounting bolts and end cover bolts, the axial force measurement state and the friction torque measurement state can be switched.

3. The ball screw pair loading test device according to claim 1, characterized in that: The driving component includes a driving motor and an integrated head frame. The integrated head frame is a single rigid body structure, and integrates the mounting seat of the driving motor and the bearing seat for supporting the measured lead screw.

4. The ball screw pair loading test device according to claim 1, characterized in that: The dual-motor top loading structure includes loading screws symmetrically arranged on both sides of the measured screw, a loading motor, a synchronous transmission mechanism and a tensioning wheel mechanism. The loading motor synchronously drives the two loading screws to rotate through the synchronous transmission mechanism.

5. The ball screw pair loading test device according to claim 1, characterized in that: The installation structure of the circular grating includes a transfer tool installed on the end face of the integrated head frame, and a screw chuck tool used to connect the end of the measured screw with the transfer tool without gap.

6. The ball screw pair loading test device according to claim 1, characterized in that: The digital display micrometer is fixed to the optical axis surface of the measured lead screw by adsorption through a magnetic base, and its measuring needle is vertically pressed against the flange end surface of the nut of the measured lead screw.

7. The ball screw pair loading test device according to claim 1, characterized in that: A limit bracket is provided on the bed, and a mechanical limit sensor and a zero position sensor are also provided on one side of the workbench, which are respectively used to achieve over-travel protection for the workbench and accurate calibration of the initial position.

8. The ball screw pair loading test device according to claim 4, characterized in that: The measuring assembly also includes a plurality of temperature sensors driven by a cylinder. After the driving motor and the loading motor stop running, the temperature sensors are driven by the cylinder to automatically adhere to the head, middle and tail surfaces of the measured screw to perform temperature measurement.

9. The ball screw pair loading test device according to claim 4, characterized in that: The synchronous transmission mechanism includes a synchronous belt and four synchronous wheels, two of which are respectively installed on the synchronous wheel shaft, and the other two synchronous wheels are installed at the tail ends of the two loading screws to ensure the synchronous loading operation of the double screws.

10. A ball screw pair loading test device according to claim 9, characterized in that: The tensioning wheel mechanism includes a tensioning wheel that is arranged in contact with the synchronous belt, and the tensioning wheel is adjusted in the vertical direction to keep the synchronous belt in a tensioned state.

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