Ball screw device load calibration test device and method

Abstract

The invention belongs to the technical field of aerospace machinery, and particularly relates to a load calibration test device and method for a ball screw device, and the device comprises a test frame, a loading actuator cylinder, a torque sensor, a ball screw, a reduction gearbox, and a strain measurement device. The loading actuating cylinder, the torque sensor and the ball screw are all arranged on the test frame, the output end of the loading actuating cylinder is connected with the strain measuring device, the ball screw and the loading actuating cylinder are coaxially arranged, one end of the ball screw is connected with the test frame, and the other end of the ball screw is connected with the reduction gearbox; the middle of the reduction gearbox is connected with the strain measuring device, and the side is connected with the torque sensor. Through coaxial loading, multi-sensor fusion and actual working condition constraint simulation, high-precision, multi-component and repeatable calibration of the load of the ball screw in a complex loaded state is realized, so that a reliable experimental basis and a data basis are provided for strength design, service life evaluation and operation monitoring of the ball screw.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aerospace machinery, and particularly relates to a ball screw device load calibration test device and method. BACKGROUND

[0002] As an important force transmission and driving mechanism of many large-scale devices, the ball screw mechanism is widely used in various mechanical transmission fields such as aviation, aerospace, shipbuilding and precision machine tools due to its unique excellent technical performance. However, existing research on ball screws mainly focuses on the application development of ball screws in various mechanical structures, the improvement of transmission efficiency, the extraction method of load spectrum, the establishment of ball screw pair load distribution model, the life research, and the like. The main concern is the practical application of ball screws and the theoretical research on load distribution, and there is a lack of research on the mechanical properties and load measurement method of ball screws applied to large mechanisms.

[0003] However, the load of the ball screw mechanism is difficult to accurately measure or estimate through direct means due to the complex load transmission path, and the load is crucial to the stability and strength of the ball screw, and is more related to the overall safety and mission reliability of the large-scale machinery using the ball screw.

[0004] Therefore, how to accurately calibrate the load of the ball screw is a problem to be solved. SUMMARY

[0005] In order to solve the above problems, the application provides a ball screw device load calibration test device and method to solve the problem that the load of the ball screw is difficult to determine in the prior art.

[0006] The technical scheme of the application is: a ball screw device load calibration test device, comprising a test frame, a loading actuator, a torque sensor, a ball screw, a reduction box and a strain measurement device;

[0007] The loading actuator, the torque sensor and the ball screw are arranged on the test frame, the output end of the loading actuator is connected with the strain measurement device, the ball screw is coaxially arranged with the loading actuator, one end of the ball screw is connected with the test frame, and the other end is connected with the reduction box; the middle part of the reduction box is connected with the strain measurement device, and the side is connected with the torque sensor.

[0008] Preferably, the output end of the loading actuator is provided with a screw joint, the screw joint is connected with the end of the ball screw, and the cylindrical area of the screw joint is pasted with strain gauges in the axial direction and 4 groups in the circumferential direction.

[0009] Preferably, a third mounting joint is arranged on the test frame, an input shaft is arranged on the third mounting joint, and the input shaft is connected with the torque sensor.

[0010] Preferably, the input shaft and the third mounting joint are connected through a spline.

[0011] Preferably, the test frame is provided with a first mounting joint and a second mounting joint, the first mounting joint is hinged with the bottom of the loading cylinder, and the second mounting joint is matched with the end of the ball screw.

[0012] Preferably, the second mounting joint is provided with a screw nut, and the screw nut is connected with the end of the ball screw.

[0013] Another technical solution of the application is a ball screw device load calibration test method, comprising:

[0014] The tensile and compressive load is applied through the loading cylinder, the load is loaded in stages, the average value of the measurement value is taken, and the relationship curve between the measured axial force and the load value is obtained;

[0015] The strain measuring device installed on the ball screw measures the strain on the force transmission path, thereby converting the screw measurement axial load Fc; the torque sensor installed on the input shaft measures the direction output torque Tc;

[0016] Based on the measured direction output torque Tc, the input shaft torque calculation value Ta corresponding to the applied axial force is obtained through the calculation formula;

[0017] The axial load Fa applied by the loading cylinder is obtained, the load measurement value and the actual value under the multi-stage tensile and compressive load condition are loaded, and the functional relationship between the axial forces Fa and Ta and the forces Fc and Tc is calibrated.

[0018] Preferably, the calculation formula of the input shaft torque calculation value Ta is:

[0019] ;

[0020] In the formula, Fa: axial load applied by the loading cylinder / N;

[0021] L: lead of screw / mm;

[0022] ηreverse: reverse efficiency of reducer;

[0023] i: forward reduction ratio of reducer.

[0024] Preferably, the output end of the loading cylinder is provided with a screw joint, the screw joint is connected with the end of the ball screw, and the cylindrical area of the screw joint is pasted with strain gauges in the axial direction and 4 groups in the circumferential direction.

[0025] Preferably, the test frame is provided with a third mounting joint, the third mounting joint is provided with an input shaft, and the input shaft is connected with a torque sensor.

[0026] Preferably, the test frame is provided with a first mounting joint and a second mounting joint, the first mounting joint is hinged with the bottom of the loading actuator cylinder, and the second mounting joint is matched with the end of the ball screw.

[0027] Preferably, when the load is graded, each group of tests is carried out for 3-5 times.

[0028] The ball screw device load calibration test device and method of the application has the following advantages:

[0029] In a strictly controlled test environment, through coaxial loading + multi-sensor fusion + actual working condition constraint simulation, high-precision, multi-component and repeatable calibration of the load of the ball screw under complex loading conditions can be realized, thereby providing reliable experimental basis and data basis for the strength design, life evaluation and operation monitoring of the ball screw, and significantly improving the safety and task reliability of large mechanical systems.

[0030] By pre-designing a test loading device accurately simulating the loading condition of the ball screw device, and accurately measuring the axial load and input torque of the screw, the function relationship between the axial load applied to the ball screw mechanism and the measured load function, and the function relationship between the input torque of the screw and the axial load are fitted through measurement, calculation and checking.

[0031] The method is simple and has strong universality, and is suitable for almost all ball screw mechanism calibration tests or load torque measurements; through screw calibration, the accuracy of the load measurement results in equipment testing is ensured, and the safety of the screw design is verified; by restoring the ball screw mechanism to a large mechanical device, the load and torque during the use of the ball screw or in the whole equipment test can be determined through the retained load measuring device. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 The figure is a schematic diagram of the overall structure of the application.

[0033] 1, test frame; 2, first mounting joint; 3, second mounting joint; 4, third mounting joint; 5, loading actuator cylinder; 6, torque sensor; 7, ball screw nut; 8, ball screw; 9, ball screw joint; 10, speed reducer; 11, input shaft; 12, strain measuring device. DETAILED DESCRIPTION

[0034] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described in a more detailed manner in the following with reference to the drawings in the embodiments of the present application. In the drawings, identical or similar labels represent identical or similar elements or elements with identical or similar functions throughout. The described embodiments are part of the embodiments of the present application, rather than all the embodiments of the present application. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the scope of protection of the present application. The embodiments of the present application will be described in detail below with reference to the drawings.

[0035] The first aspect of the present application provides a ball screw device load calibration test device, such as Figure 1 , comprising a test frame 1, a loading cylinder 5, a torque sensor 6, a ball screw 8, a reduction box 10 and a strain measurement device 12.

[0036] The test frame 1 is used to provide a mounting position for the ball screw 8, the clamp, the loading cylinder 5, is fixed to the ground, and ensures the stability of the entire test bench.

[0037] The loading cylinder 5, the torque sensor 6 and the ball screw 8 are all arranged on the test frame 1, the output end of the loading cylinder 5 is connected with the strain measurement device 12, the ball screw 8 is coaxially arranged with the loading cylinder 5, one end of the ball screw 8 is connected with the test frame 1, and the other end is connected with the reduction box 10; the middle part of the reduction box 10 is connected with the strain measurement device 12, and the side is connected with the torque sensor 6.

[0038] The loading cylinder 5 is used to provide the tension and compression load in the calibration test, the torque sensor 6 is used for torque measurement, and the input shaft 11 is used as the original driving input end of the ball screw 8.

[0039] The strain measurement device 12 is arranged on the joint force transmission path of the ball screw 8, and the change of the measured strain and the screw axial load is monitored.

[0040] The load is loaded by controlling the loading cylinder 5, the ball screw 8 is driven to work under different loads, the axial force and the torque during loading are obtained through the torque sensor 6, and then the strain data collected by the strain measurement device 12 are combined to realize the calibration of the screw after data processing.

[0041] Through the screw calibration work, the accuracy of the load measurement result in the equipment test is ensured, and the safety of the screw design is verified.

[0042] Preferably, the output end of the loading actuator 5 is equipped with a lead screw connector, which is connected to the end of the ball screw 8. Strain gauges are attached to the cylindrical area of ​​the lead screw connector along the axial direction, and four sets are attached along the circumferential direction. Accurate strain data is obtained by calculating the average value of the strain data collected by the strain gauges.

[0043] Preferably, the test frame 1 is provided with a third mounting joint 4, and the third mounting joint 4 is provided with an input shaft 11, which is connected to the torque sensor 6. The input shaft 11 and the third mounting joint 4 are connected by a spline.

[0044] The test frame 1 is provided with a first mounting joint 2 and a second mounting joint 3. The first mounting joint 2 is hinged to the bottom of the loading actuator cylinder 5, and the second mounting joint 3 is engaged with the end of the ball screw 8.

[0045] The ball screw mechanism 8 was installed on the test frame 1 using three sets of mounting joints.

[0046] Preferably, the second mounting joint 3 is provided with a lead screw nut, which is connected to the end of the ball screw 8. Tightening the lead screw nut secures the ball screw 8.

[0047] As another specific implementation, a load calibration test method for a ball screw 8 device includes:

[0048] By applying tensile and compressive loads through the loading actuator 5, the loads are applied in stages, and the average value of the measured values ​​is taken to obtain the relationship curves between the measured axial force, torque and the load values.

[0049] The strain measuring device 12, mounted on the ball screw 8, measures the strain along the force transmission path, thereby converting the axial load Fc of the screw into a measurement; the torque sensor 6, mounted on the input shaft 11, measures the directional output torque Tc.

[0050] Based on the output torque Tc in the measurement direction, the calculated value Ta of the input shaft 11 torque corresponding to the applied axial force is obtained through the calculation formula;

[0051] Obtain the axial load Fa applied by the loading actuator 5, and calibrate the functional relationship between axial forces Fa, Ta and Fc, Tc based on the measured and actual load values ​​under multi-level tensile and compressive load conditions.

[0052] By examining the functional relationship between the measured values ​​and actual values ​​obtained from the entire set of tests, the load measured in the test on the large equipment using ball screw 8 is corrected to ensure its accuracy and verify the safety of the screw design.

[0053] Preferably, the formula for calculating the torque value Ta of the input shaft 11 is:

[0054] Ta = (Fa × L × η_inverse) / (2 × π × i);

[0055] Fa: axial load applied by loading cylinder 5, N;

[0056] L: lead of screw, mm;

[0057] ηreverse: reverse efficiency of reducer;

[0058] i: forward reduction ratio of reducer.

[0059] Preferably, the output end of the loading cylinder 5 is provided with a screw joint connected with the end of the ball screw 8, and the cylindrical area of the screw joint is pasted with axial strain gauges and 4 groups of circumferential strain gauges.

[0060] Preferably, the test frame 1 is provided with a third mounting joint 4, and the third mounting joint 4 is provided with an input shaft 11 connected with the torque sensor 6.

[0061] Preferably, the test frame 1 is provided with a first mounting joint 2 and a second mounting joint 3, the first mounting joint 2 is hingedly connected with the bottom of the loading cylinder 5, and the second mounting joint 3 is matched with the end of the ball screw 8.

[0062] Preferably, when the load is loaded in stages, 3-5 tests are carried out for each group of tests, and the data of different groups of tests are calculated by mean value to ensure accuracy.

[0063] In summary, the application has the following advantages:

[0064] In a strictly controlled test environment, through coaxial loading + multi-sensor fusion + actual working condition constraint simulation, high-precision, multi-component and repeatable calibration of the load of the ball screw under complex load state can be realized, thereby providing reliable experimental basis and data basis for strength design, life evaluation and operation monitoring of the ball screw, and significantly improving the safety and task reliability of large mechanical systems.

[0065] By pre-designing a test loading device accurately simulating the loading condition of the ball screw device, an accurate method for measuring the axial load and input torque of the screw is provided, and by measuring, calculating and checking, the function relationship between the axial load applied to the ball screw mechanism and the measured load, and the function relationship between the input torque of the screw and the axial load are fitted.

[0066] The method is simple and universal, and is suitable for almost all ball screw mechanism calibration tests or load torque measurement; through the screw calibration work, the accuracy of the load measurement result in the equipment test is ensured, and the safety of the screw design is verified; when the ball screw mechanism is restored to a large mechanical device, the load and torque during the use of the ball screw or in the whole equipment test can be determined through the retained load measuring device.

[0067] The above merely provides the specific implementation of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A load calibration test device for a ball screw (8) device, characterized in that, It includes a test frame (1), a loading actuator (5), a torque sensor (6), a ball screw (8), a gearbox (10), and a strain measurement device (12); The loading actuator (5), torque sensor (6) and ball screw (8) are all mounted on the test frame (1). The output end of the loading actuator (5) is connected to the strain measuring device (12). The ball screw (8) is coaxially mounted with the loading actuator (5). One end of the ball screw (8) is connected to the test frame (1) and the other end is connected to the reduction gearbox (10). The middle part of the reduction gearbox (10) is connected to the strain measuring device (12) and the side is connected to the torque sensor (6).

2. The load calibration test device for the ball screw (8) device as described in claim 1, characterized in that, The output end of the loading actuator (5) is provided with a lead screw connector, which is connected to the end of the ball screw (8). Strain gauges are pasted axially in the cylindrical area of ​​the lead screw connector, and four sets are pasted circumferentially.

3. The load calibration test device for the ball screw (8) device as described in claim 1, characterized in that, The test frame (1) is provided with a third mounting joint (4), and the third mounting joint (4) is provided with an input shaft (11), which is connected to a torque sensor (6).

4. The load calibration test device for the ball screw (8) device as described in claim 3, characterized in that, The input shaft (11) is connected to the third mounting joint (4) via a spline.

5. The load calibration test device for the ball screw (8) device as described in claim 1, characterized in that, The test frame (1) is provided with a first mounting joint (2) and a second mounting joint (3). The first mounting joint (2) is hinged to the bottom of the loading actuator (5), and the second mounting joint (3) is engaged with the end of the ball screw (8).

6. The load calibration test device for the ball screw (8) device as described in claim 5, characterized in that, The second mounting joint (3) is provided with a lead screw nut, which is connected to the end of the ball screw (8).

7. A load calibration test method for a ball screw (8) device, comprising the method described in any one of claims 1-6, characterized in that, include: By applying tensile and compressive loads through the loading actuator (5), the loads are applied in stages, and the average value of the measured values ​​is taken to obtain the relationship curve between the measured axial force, torque and the load value. The strain measuring device (12) installed on the ball screw (8) measures the strain on the force transmission path, thereby converting the axial load Fc of the screw to be measured; the torque sensor (6) installed on the input shaft (11) measures the directional output torque Tc; Based on the output torque Tc in the measurement direction, the calculated value Ta of the input shaft (11) torque corresponding to the applied axial force is obtained through the calculation formula; Obtain the axial load Fa applied by the loading actuator (5), and calibrate the functional relationship between axial forces Fa, Ta and Fc, Tc based on the load measurement and actual values ​​under multi-level tensile and compressive load conditions.

8. The load calibration test method for the ball screw device as described in claim 7, characterized in that, The formula for calculating the input shaft torque value Ta is: ； In the formula, Fa: axial load applied to the actuator cylinder / N; L: Lead screw pitch / mm; ηreverse: Reverse efficiency of the reducer; i: Forward reduction ratio of the reducer.

9. The load calibration test method for the ball screw (8) device as described in claim 7, characterized in that, The output end of the loading actuator (5) is provided with a lead screw connector, which is connected to the end of the ball screw (8). Strain gauges are pasted axially in the cylindrical area of ​​the lead screw connector, and four sets are pasted circumferentially.

10. The load calibration test method for the ball screw (8) device as described in claim 7, characterized in that, The test frame (1) is provided with a third mounting joint (4), and the third mounting joint (4) is provided with an input shaft (11), which is connected to a torque sensor (6).

11. The load calibration test method for the ball screw (8) device as described in claim 7, characterized in that, The test frame (1) is provided with a first mounting joint (2) and a second mounting joint (3). The first mounting joint (2) is hinged to the bottom of the loading actuator (5), and the second mounting joint (3) is engaged with the end of the ball screw (8).

12. The load calibration test method for the ball screw (8) device as described in claim 7, characterized in that, When performing graded load loading, each test group is conducted 3-5 times.

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