A large-size measuring beam calibration device and a calibration method

Abstract

The present application relates to a kind of large size measurement beam calibration device and calibration method, including clamping fixture, the side of clamping fixture is connected with fixed base, clamping fixture includes respectively with fixed base connection lower fixed plate and upper pressing structure, the upper surface of lower fixed plate places measurement beam, upper pressing structure is cooperated with the upper part of measurement beam and fixes measurement beam, the measurement beam on the side of clamping fixture is cooperated with installation frame structure, frame structure is used to connect loading weight;It also includes pulley structure with loading weight cooperation.By setting the clamping fixture of lower fixed plate and upper pressing structure cooperation realizes the clamping of multiple specifications measurement beam, the frame structure of connecting loading weight and pulley structure combination realizes the bending moment, shear and torsion coefficient calibration of measurement beam in the case where not dismantling load loading tool, simultaneously when torsion coefficient calibration, equal size, opposite direction force is applied to the both sides of measurement beam, improve the calibration precision of torsion coefficient.

Description

Technical Field

[0001] This invention relates to the field of wave load testing and measurement technology for ship models, and in particular to a calibration device and method for a large-size measuring beam. Background Technology

[0002] In order to conduct experimental research on the wave loads borne by ships with large openings when navigating in waves, it is necessary to design and fabricate a large-size measuring beam with a special form. Before the formal test, the vertical bending moment, horizontal bending moment, vertical shear force, horizontal shear force, and torque of the measuring beam need to be calibrated. The wave loads borne by the ship are obtained by using the calibration coefficients and the time history signals during the formal test.

[0003] Traditional calibration devices are only suitable for measuring beams with small cross-sections, making it difficult to calibrate large measuring beams. For bending moment and shear force calibration, loads are applied by suspending weights with ropes, while for torque calibration, one end of the measuring beam is fixed and the other end is loaded on a single side. Torque calibration measuring beams undergo both torsional and bending deformations, which can affect the accuracy of the torsional calibration coefficient and consequently the accuracy of wave load tests on ship models. Furthermore, the suspension fixtures for the weights must be varied depending on the calibration object, making operation somewhat inconvenient. Summary of the Invention

[0004] To address the shortcomings of existing production technologies, the applicant provides a large-size measuring beam calibration device and method, which is applicable to the clamping of measuring beams of various specifications. When calibrating bending moment, shear force, and torque, it is not necessary to change the load-bearing tooling, making operation convenient. At the same time, it facilitates the accurate application of loads during the calibration process, thereby accurately measuring the wave loads experienced by the ship model when sailing in waves.

[0005] The technical solution adopted in this invention is as follows:

[0006] A large-size measuring beam calibration device includes a clamping and fixing device. The side of the clamping and fixing device is connected to a fixed foundation. The clamping and fixing device includes a lower fixing plate and an upper pressing structure, which are respectively connected to the fixed foundation. A measuring beam is placed on the upper surface of the lower fixing plate. The upper pressing structure cooperates with the upper part of the measuring beam to fix the measuring beam. A frame structure is installed on the measuring beam on one side of the clamping and fixing device. The frame structure is used to connect the loaded weight.

[0007] It also includes a pulley structure that works in conjunction with the loaded weight.

[0008] As a further improvement to the above technical solution:

[0009] The upper clamping structure comprises a movable plate that mates with the upper part of the measuring beam, an upper fixed plate above the movable plate, a side of the upper fixed plate connected to a fixed foundation, and a clamping adjustment component that mates with the movable plate on the upper fixed plate. The clamping adjustment component is used to adjust the relative distance between the movable plate and the upper fixed plate so that the movable plate mates with the measuring beam.

[0010] The upper fixing plate has the same structure as the lower fixing plate. The upper fixing plate has the following structure: it includes a fixing base plate, and one end of the fixing base plate is provided with a plate-shaped mounting part perpendicular to the upper surface of the fixing base plate. The mounting part has a mounting hole and cooperates with the fixing base.

[0011] The upper fixing plate has multiple threaded holes on its fixing base plate. The clamping adjustment component is a fastener that is threadedly engaged with the threaded holes. One end of the clamping adjustment component passes through the threaded holes and engages with the upper surface of the movable plate.

[0012] The frame structure comprises an upper frame member and a lower frame member arranged in parallel and staggered configurations. The upper and lower frame members have identical structures and are symmetrical about the center of the measuring beam cross-section. An adjustment groove is provided through the middle of the upper surface of the upper frame member, with the adjustment grooves of the upper and lower frame members corresponding vertically. A pair of long screw assemblies are provided through the adjustment grooves of the upper and lower frame members, with their two ends engaging with the upper and lower frame members respectively. The upper and lower frame members and the pair of long screw assemblies together form a ring structure, the interior of which engages with the outer periphery of the measuring beam cross-section. The load includes a first weight group suspended from one end of the upper frame member and a second weight group suspended from one end of the lower frame member, with the first and second weight groups located on opposite sides of the frame structure.

[0013] The first weight set is connected to the upper frame component via a flexible connecting line. The flexible connecting line cooperates with the fixed pulley at the upper end of the pulley structure, and the flexible connecting lines on both sides of the fixed pulley are parallel to each other.

[0014] The pulley structure includes a pulley bracket, the upper part of which is rotatably connected to a fixed pulley, and a flexible connecting line between the frame structure and the loaded weight that cooperates with the fixed pulley.

[0015] A calibration method for a large-size measuring beam calibration device includes the following steps:

[0016] Step 1: Install the measuring beam:

[0017] The clamping and fixing device is connected to the fixed foundation. The initial relative position of the lower fixing plate and the upper pressing structure is adjusted so that the measuring beam can be placed between the lower fixing plate and the upper pressing structure. At the same time, the lower fixing plate plays the role of supporting the measuring beam. Then, the upper pressing structure cooperates with the measuring beam to clamp the measuring beam, so that the measuring beam maintains a fixed position during the measurement process.

[0018] Step 2: Measurement Preparation

[0019] Determine the location of the measurement profile and the installation location of the frame structure. The measurement profile is located between the frame structure and the clamping and fixing device. The distance between the measurement profile and the clamping and fixing device is L1, and the distance between the frame structure and the measurement profile is L2.

[0020] According to the test requirements, strain gauges were attached to the corresponding positions of the measuring beam, and strain signals at various positions of the measuring beam were obtained through the strain gauges during the test.

[0021] The first set of weights is suspended at one end of the upper frame of the installed frame structure, and the second set of weights is suspended at one end of the lower frame of the installed frame structure. The first set of weights and the second set of weights are located on both sides of the frame structure. The horizontal distance from the suspension point of the first set of weights and the center of the cross section of the measuring beam is equal to L3, and the suspension points of the first set of weights and the second set of weights are symmetrical about the center of the cross section of the measuring beam.

[0022] Each strain gauge is connected to a dynamic strain gauge to obtain the signal of each strain gauge during the calibration process;

[0023] Step 3: Obtain the strain signal changes at various locations on the measuring beam:

[0024] (i) Obtaining the strain gauge signal change ε ​​for measuring bending moment V :

[0025] Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first and second weight groups, and then simultaneously and sequentially unloaded, ensuring that the strain gauge signal change ε ​​in the first and second weight groups is maintained. V ;

[0026] (ii) Obtaining the strain gauge signal change F for measuring shear force Z :

[0027] Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first and second weight groups, and then simultaneously and sequentially unloaded, ensuring that the magnitude and direction of the forces applied by the first and second weight groups are equal. The change in strain gauge signal F used to measure shear force is obtained during each loading and unloading. Z ;

[0028] (iii) Strain gauge signal change M used to measure torque x Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first and second weight groups, and then simultaneously and sequentially unloaded, ensuring that the forces applied to the first and second weight groups are equal in magnitude and opposite in direction. The change in signal M of the strain gauge used to measure torque is obtained during each loading and unloading. x ;

[0029] Step 4: Calculate and obtain the calibration coefficient of the measuring beam:

[0030] When a weight of mass m is loaded in a single load, the vertical bending moment on the measuring section is M = 2mgL2 and the shear force on the measuring section is F = 2mg, and the torque on the measuring section is T = 2mgL3, where g is the acceleration due to gravity.

[0031] (a) The bending moment calibration factor is δ V :

[0032] ε is the change in strain gauge signal used to measure bending moment during each loading and unloading. V The average value;

[0033] (ii) The shear force calibration factor is δ F :

[0034] F is the change in strain gauge signal used to measure shear force during each loading and unloading. Z The average value;

[0035] (iii) The torsion calibration coefficient is δ:

[0036] M is the change in strain gauge signal used to measure torque during each loading and unloading. X The average value;

[0037] Bending moment calibration factor δ V The shear force calibration factor is δ F The torsional calibration coefficient δ is the calibration coefficient of the measuring beam.

[0038] As a further improvement to the above technical solution:

[0039] In the third step: the forces applied by the first weight group and the second weight group are equal in magnitude and opposite in direction. This is achieved by extending the flexible connecting line between the first weight group and the first weight group's hanging point vertically upwards, passing it around the fixed pulley, and then allowing the first weight group to hang down naturally. At the same time, the second weight group is connected to the second weight group's hanging point through the flexible connecting line and then hangs down naturally.

[0040] After completing the calibration operations from step one to step four, remove the measuring beam from the clamping and fixing device, and at the same time remove the frame structure. Rotate the measuring beam 90 degrees around the axis and repeat the calibration operations from step one to step four.

[0041] The beneficial effects of this invention are as follows:

[0042] This invention features a compact and reasonable structure, and is easy to operate. It achieves the clamping and fixing of various specifications of measuring beams by setting up a clamping and fixing device with a lower fixing plate and an upper pressing structure. The combination of the frame structure and pulley structure connecting the loaded weight enables the calibration of the bending moment, shear force and torque coefficient of the measuring beam without removing the load loading fixture.

[0043] Furthermore, the present invention also has the following advantages:

[0044] (1) The clamping and fixing device has good applicability and can be used for measuring beams of various specifications and sizes. The measuring beam can be fixed by adjusting the position of the upper fixing plate, the lower fixing plate and the movable plate. It is convenient to use and easy to operate.

[0045] (2) The first weight set is used in conjunction with the fixed pulley of the pulley structure to change the direction of the force applied by the first weight set to the measuring beam, so as to switch the calibration object without changing the load loading tool, which is convenient to operate.

[0046] (3) The first weight group is used in conjunction with the fixed pulley of the pulley structure so that when calibrating the torque coefficient, the first weight group and the second weight group apply forces of equal magnitude and opposite direction to both sides of the measuring beam. This ensures that the external load on the measuring beam is only torque, thereby avoiding the interference of bending moment and shear force on the torque signal, minimizing the uncertainties in the torque coefficient calibration process, and improving the calibration accuracy of the torque coefficient. Attached Figure Description

[0047] Figure 1 This is a side view of the present invention.

[0048] Figure 2 This is the front view of the present invention.

[0049] Figure 3 for Figure 2 Enlarged view of point A.

[0050] Figure 4 This is a schematic diagram of the framework structure of the present invention.

[0051] Figure 5 This is a schematic diagram of the combined use of the frame structure and pulley structure of the present invention.

[0052] Figure 6 This is a top view of the fixing plate of the present invention.

[0053] Figure 7 This is a side view of the fixing plate of the present invention.

[0054] Figure 8 This is a top view of the upper frame component of the present invention.

[0055] Figure 9 for Figure 8 Sectional view at point BB.

[0056] Figure 10 This is a front view of the pulley structure of the present invention.

[0057] Figure 11 This is a top view of the pulley structure of the present invention.

[0058] Figure 12 This is a side view of the pulley structure of the present invention.

[0059] Among them: 10. Clamping and fixing device;

[0060] 11. Upper fixed plate; 12. Lower fixed plate; 13. Movable plate; 14. Pressing adjustment component; 15. Upper connecting bolt; 16. Lower connecting bolt;

[0061] 1101. Fixed substrate; 1102. Mounting part; 1103. Mounting hole; 1104. Threaded hole;

[0062] 20. Frame structure;

[0063] 21. Top frame component; 22. Bottom frame component; 23. Long screw assembly;

[0064] 2101. Rectangular rod; 2102. Connecting block; 2103. Adjustment groove;

[0065] 3. Measure the beam;

[0066] 40. Loading the weight; 41. First set of weights; 42. Second set of weights;

[0067] 50. Pulley structure; 51. Fixed pulley; 52. Pulley bracket; 5201. Support leg; 5202. I-beam; 5203. Rotating shaft;

[0068] 6. Fix the foundation;

[0069] S, the measurement profile; L1, the distance between the measurement profile and the clamping device; L2, the distance between the frame structure and the measurement profile; L3, the horizontal distance between the hanging points of the first and second weight groups and the center of the measurement beam section. Detailed Implementation

[0070] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0071] like Figures 1-5 As shown, the large-size measuring beam calibration device of Embodiment 1 includes a clamping and fixing device 10. The side of the clamping and fixing device 10 is connected to the fixing base 6. The clamping and fixing device 10 includes a lower fixing plate 12 and an upper pressing structure, which are respectively connected to the fixing base 6. The measuring beam 3 is placed on the upper surface of the lower fixing plate 12. The upper pressing structure cooperates with the upper part of the measuring beam 3 to fix the measuring beam 3. A frame structure 20 is installed on the measuring beam 3 on one side of the clamping and fixing device 10. The frame structure 20 is used to connect the loaded weight 40.

[0072] It also includes a pulley structure 50 that works in conjunction with the loaded weight 40.

[0073] Strain gauges are attached to the corresponding positions of the measuring beam 3. The strain signals at each position of the measuring beam 3 are obtained through the strain gauges. Each strain gauge is connected to a dynamic strain gauge to obtain the signals of each strain gauge during the calibration process.

[0074] The fixed foundation 6 can be a wall, column, bracket, or other structure. Multiple sets of mounting holes corresponding to the clamping and fixing device 10 can be provided on the fixed foundation 6, facilitating the adjustment of the installation height and position of the clamping and fixing device 10 according to different structures of the measuring beam 3. The frame structure 20 serves as a load-loading fixture to connect the load 40. The position of the applied load is adjusted by adjusting the position of the frame structure 20 on the measuring beam 3. When the load 40 acts alone, it applies bending moment and shear loads to the measuring beam 3 for bending moment and torque calibration. When the load 40 is used in conjunction with the pulley structure 50, it applies torque to the measuring beam 3 by changing the direction of the applied load for torque calibration.

[0075] The clamping and fixing device 10, which is set up with the lower fixing plate 12 and the upper pressing structure, can clamp various specifications of measuring beams 3. The frame structure 20 connecting the loaded weight 40 and the pulley structure 50 are combined to calibrate the bending moment, shear force and torque coefficient of the measuring beam without removing the load loading tool.

[0076] like Figures 1-7 As shown, the upper clamping structure includes a movable plate 13 that mates with the upper part of the measuring beam 3. An upper fixed plate 11 is provided above the movable plate 13. The side of the upper fixed plate 11 is connected to the fixed base 6. A clamping adjustment component 14 that mates with the movable plate 13 is provided on the upper fixed plate 11. The clamping adjustment component 14 is used to adjust the relative distance between the movable plate 13 and the upper fixed plate 11 so that the movable plate 13 mates with the measuring beam 3.

[0077] The upper fixing plate 11 and the lower fixing plate 12 have the same structure. The upper fixing plate 11 has the following structure: it includes a fixing base plate 1101. One end of the fixing base plate 1101 is provided with a plate-shaped mounting part 1102 perpendicular to the upper surface of the fixing base plate 1101. The mounting part 1102 has a mounting hole 1103 and cooperates with the fixing base 6.

[0078] The upper fixing plate 11 has a plurality of threaded holes 1104 on its fixing base plate 11. The clamping adjustment member 14 is a fastener that is threadedly engaged with the threaded holes 1104. One end of the clamping adjustment member 14 passes through the threaded holes 1104 and engages with the upper surface of the movable plate 13.

[0079] The mounting holes 1103 on the sides of the upper fixing plate 11 and the lower fixing plate 12 are respectively fitted with upper connecting bolts 15 and lower connecting bolts 16. The upper connecting bolts 15 and lower connecting bolts 16 are fitted with the assembly holes of the fixed base 6 to fix the upper fixing plate 11 and the lower fixing plate 12 to the fixed base 6. The measuring beam 3 is placed on the upper surface of the lower fixing plate 12, which supports the measuring beam 3 and provides space around the measuring beam 3 for applying load. By placing a movable plate 13 that mates with the upper part of the measuring beam 3 on the upper surface of the measuring beam 3, the contact area between the upper clamping structure and the measuring beam 3 is increased. At the same time, the relative position between the clamping adjustment member 14 and the upper fixing plate 11 is adjusted to achieve the clamping effect of the clamping adjustment member 14 on the movable plate 13, thereby pressing the measuring beam 3 onto the lower fixing plate 12 and achieving the clamping effect of the measuring beam 3.

[0080] The clamping and fixing device 10 has good applicability and can be used for measuring beams 3 of various specifications and sizes. The measuring beam 3 can be fixed by adjusting the positions of the upper fixing plate 11, the lower fixing plate 12 and the movable plate 13. It is convenient to use and easy to operate.

[0081] like Figures 2-9 As shown, the frame structure 20 includes an upper frame member 21 and a lower frame member 22 arranged in parallel and staggered positions. The upper frame member 21 and the lower frame member 22 have the same structure and are symmetrical about the center of the measuring beam 3 section. An adjustment groove 2103 is provided through the middle of the upper surface of the upper frame member 21. The adjustment grooves 2103 of the upper frame member 21 and the lower frame member 22 correspond vertically. At the same time, a pair of long screw assemblies 23 are provided through the adjustment grooves 2103 of the upper frame member 21 and the lower frame member 22. The two ends of the long screw assemblies 23 are respectively engaged with the upper frame member 21 and the lower frame member 22. The upper frame member 21, the lower frame member 22 and the pair of long screw assemblies 23 form a ring structure. The inside of the ring structure is engaged with the outer periphery of the measuring beam 3 section. The loaded weight 40 includes a first weight group 41 suspended at one end of the upper frame member 21 and a second weight group 42 suspended at one end of the lower frame member 22. The first weight group 41 and the second weight group 42 are located on both sides of the frame structure 20.

[0082] Before installing the frame structure 20, it is necessary to determine the position of the measurement section S and the installation position of the frame structure 20. The measurement section S is located between the frame structure 20 and the clamping and fixing device 10. The distance between the measurement section S and the clamping and fixing device 10 is L1, and the distance between the frame structure 20 and the measurement section S is L2.

[0083] The upper frame component 21 has the following structure: it includes two parallel and spaced rectangular rods 2101, the two ends of which are connected by connecting blocks 2102 respectively, and the connecting blocks 2102 and the rectangular rods 2101 enclose an adjustment groove 2103.

[0084] The center of symmetry of the upper frame member 21 and the lower frame member 22 is the center of the annular structure. After the frame structure 20 is clamped outside the measuring beam 3, the center of the annular structure coincides with the center of the cross section of the measuring beam 3. When a weight of mass m is simultaneously applied to the positions corresponding to the first weight group 41 and the second weight group 42, the vertical bending moment borne by the measuring section S is M = 2mgL2 and the shear force borne by the measuring section S is F = 2mg.

[0085] like Figure 5 As shown, the first weight group 41 is connected to the upper frame component 21 via a flexible connecting line. The flexible connecting line cooperates with the fixed pulley 51 at the upper end of the pulley structure 50, and the flexible connecting lines on both sides of the fixed pulley 51 are parallel to each other. The first weight group 41 hangs naturally. Therefore, when a weight of mass m is simultaneously applied to the corresponding positions of the first weight group 41 and the second weight group 42, the torque borne by the measuring profile S is T = 2mgL3. Due to the action of the fixed pulley 51, the first weight group 41 and the second weight group 42 apply forces of equal magnitude and opposite direction to both sides of the measuring beam 3, so that the external load borne by the measuring beam 3 is only torque. This avoids the interference of bending moment and shear force on the torque signal, minimizes the uncertainties in the torque coefficient calibration process, and improves the calibration accuracy of the torque coefficient.

[0086] like Figures 10-12 As shown, the pulley structure 50 has the following structure: it includes a pulley bracket 52, the upper part of which is rotatably connected to a fixed pulley 51, and the flexible connecting line between the frame structure 20 and the loaded weight 40 is in cooperation with the fixed pulley 51.

[0087] The pulley bracket 52 includes two parallel I-beams 5202, which are perpendicular to the ground. The upper ends of the two I-beams 5202 are connected by a pivot 5203. A fixed pulley 51 is rotatably connected to the pivot 5203. Support legs 5201 are symmetrically arranged on both sides of the lower end of the I-beams 5202 to support the I-beams 5202 and keep them in a vertical state.

[0088] The calibration method for the large-size measuring beam calibration device in Example 2 includes the following steps:

[0089] Step 1: Install measuring beam 3:

[0090] The clamping and fixing device 10 is connected to the fixed base 6. The initial relative position of the lower fixing plate 12 and the upper pressing structure is adjusted so that the measuring beam 3 can be placed between the lower fixing plate 12 and the upper pressing structure. At the same time, the lower fixing plate 12 plays the role of supporting the measuring beam 3. Then, the upper pressing structure cooperates with the measuring beam 3 to clamp the measuring beam 3, so that the measuring beam 3 maintains a fixed position during the measurement process.

[0091] Step 2: Measurement Preparation

[0092] Determine the position of the measurement section S and the installation position of the frame structure 20. The measurement section S is located between the frame structure 20 and the clamping and fixing device 10. The distance between the measurement section S and the clamping and fixing device 10 is L1, and the distance between the frame structure 20 and the measurement section S is L2.

[0093] According to the test requirements, strain gauges were attached to the corresponding positions of the measuring beam 3. During the test, strain signals at various positions of the measuring beam 3 were obtained through the strain gauges.

[0094] The first weight set 41 is suspended at one end of the upper frame piece 21 of the installed frame structure 20, and the second weight set 42 is suspended at one end of the lower frame piece 22 of the installed frame structure 20. The first weight set 41 and the second weight set 42 are located on both sides of the frame structure 20, respectively. The horizontal distance from the suspension point of the first weight set 41 and the second weight set 42 to the center of the cross section of the measuring beam 3 is equal, both being L3, and the suspension points of the first weight set 41 and the second weight set 42 are symmetrical about the center of the cross section of the measuring beam 3.

[0095] Each strain gauge is connected to a dynamic strain gauge to obtain the signal of each strain gauge during the calibration process;

[0096] Step 3: Obtain the strain signal changes at various locations on beam 3:

[0097] (i) Obtaining the strain gauge signal change ε ​​for measuring bending moment V :

[0098] Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first weight group 41 and the second weight group 42, and then simultaneously and sequentially unloaded, ensuring that the magnitude and direction of the forces applied to the first weight group 41 and the second weight group 42 are equal. The change in strain gauge signal ε used to measure the bending moment is obtained during each loading and unloading. V ;

[0099] (ii) Obtaining the strain gauge signal change F for measuring shear forceZ :

[0100] Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first weight group 41 and the second weight group 42, and then simultaneously and sequentially unloaded, ensuring that the magnitude and direction of the forces applied to the first weight group 41 and the second weight group 42 are equal. The change in strain gauge signal F used to measure shear force is obtained during each loading and unloading. Z ;

[0101] (iii) Strain gauge signal change M used to measure torque X Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first weight group 41 and the second weight group 42, and then simultaneously and sequentially unloaded, ensuring that the forces applied to the first weight group 41 and the second weight group 42 are equal in magnitude and opposite in direction. The change in the signal M of the strain gauge used to measure the torque is obtained during each loading and unloading. x ;

[0102] Step 4: Calculate and obtain the calibration coefficient of measuring beam 3:

[0103] When a weight of mass m is loaded in a single load, the vertical bending moment on the measuring section S is M = 2mgL2 and the shear force on the measuring section S is F = 2mg, the torque on the measuring section S is T = 2mgL3, and g is the acceleration due to gravity.

[0104] (a) The bending moment calibration factor is δ V :

[0105] ε is the change in strain gauge signal used to measure bending moment during each loading and unloading. V The average value;

[0106] (ii) The shear force calibration factor is δ F :

[0107] F is the change in strain gauge signal used to measure shear force during each loading and unloading. z The average value;

[0108] (III) The torsion calibration coefficient is δ

[0109] M is the change in strain gauge signal used to measure torque during each loading and unloading. x The average value;

[0110] Bending moment calibration factor δ V The shear force calibration factor is δ FThe torsional calibration coefficient δ is the calibration coefficient for measuring beam 3.

[0111] The calibration method for the large-size measuring beam calibration device in Example 3 includes the following steps:

[0112] Step 1: Install measuring beam 3:

[0113] Keep the bottom of measuring beam 3 horizontal;

[0114] The clamping and fixing device 10 is connected to the fixed base 6. The initial relative position of the lower fixing plate 12 and the upper pressing structure is adjusted so that the measuring beam 3 can be placed between the lower fixing plate 12 and the upper pressing structure. At the same time, the lower fixing plate 12 plays the role of supporting the measuring beam 3. Then, the upper pressing structure cooperates with the measuring beam 3 to clamp the measuring beam 3, so that the measuring beam 3 maintains a fixed position during the measurement process.

[0115] When clamping the measuring beam 3 with the upper clamping structure, first place the movable plate 13 that matches the upper part of the measuring beam 3 on the upper surface of the measuring beam 3, adjust the relative position between the clamping adjustment component 14 and the upper fixed plate 11 so that the clamping adjustment component 14 clamps the movable plate 13, thereby pressing the measuring beam 3 onto the lower fixed plate 12 to achieve the clamping effect on the measuring beam 3.

[0116] Step 2: Measurement Preparation

[0117] Determine the position of the measurement section S and the installation position of the frame structure 20. The measurement section S is located between the frame structure 20 and the clamping and fixing device 10. The distance between the measurement section S and the clamping and fixing device 10 is L1, and the distance between the frame structure 20 and the measurement section S is L2.

[0118] According to the test requirements, strain gauges were attached to the corresponding positions of the measuring beam 3. During the test, strain signals at various positions of the measuring beam 3 were obtained through the strain gauges.

[0119] The first weight set 41 is suspended at one end of the upper frame piece 21 of the installed frame structure 20, and the second weight set 42 is suspended at one end of the lower frame piece 22 of the installed frame structure 20. The first weight set 41 and the second weight set 42 are located on both sides of the frame structure 20, respectively. The horizontal distance from the suspension point of the first weight set 41 and the second weight set 42 to the center of the cross section of the measuring beam 3 is equal, both being L3, and the suspension points of the first weight set 41 and the second weight set 42 are symmetrical about the center of the cross section of the measuring beam 3.

[0120] Each strain gauge is connected to a dynamic strain gauge to obtain the signal of each strain gauge during the calibration process;

[0121] Step 3: Obtain the strain signal changes at various locations on beam 3:

[0122] (i) Obtaining the strain gauge signal change ε ​​for measuring bending moment V :

[0123] Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first weight group 41 and the second weight group 42, and then simultaneously and sequentially unloaded, ensuring that the magnitude and direction of the forces applied to the first weight group 41 and the second weight group 42 are equal. The change in strain gauge signal ε used to measure the bending moment is obtained during each loading and unloading. V ;

[0124] (ii) Obtaining the strain gauge signal change F for measuring shear force Z :

[0125] Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first weight group 41 and the second weight group 42, and then simultaneously and sequentially unloaded, ensuring that the magnitude and direction of the forces applied to the first weight group 41 and the second weight group 42 are equal. The change in strain gauge signal F used to measure shear force is obtained during each loading and unloading. z ;

[0126] (iii) Strain gauge signal change M used to measure torque X By extending the flexible connecting line between the first weight group (41) and the first weight group (42)'s suspension point vertically upwards and passing over the fixed pulley (51), the first weight group (41) hangs down naturally. At the same time, the second weight group (42) is connected to the second weight group (42)'s suspension point via the flexible connecting line and hangs down naturally. Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first weight group 41 and the second weight group 42, and then simultaneously and sequentially unloaded, ensuring that the forces applied to the first weight group 41 and the second weight group 42 are equal in magnitude and opposite in direction, the change in the signal M of the strain gauge used to measure the torque is obtained during each loading and unloading. X ;

[0127] Step 4: Calculate and obtain the calibration coefficient of measuring beam 3:

[0128] When a weight of mass m is loaded in a single load, the vertical bending moment on the measuring section S is M = 2mgL2 and the shear force on the measuring section S is F = 2mg, the torque on the measuring section S is T = 2mgL3, and g is the acceleration due to gravity.

[0129] (a) The bending moment calibration factor is δ V :

[0130] ε is the change in strain gauge signal used to measure bending moment during each loading and unloading. V The average value;

[0131] (ii) The shear force calibration factor is δ F :

[0132] F is the change in strain gauge signal used to measure shear force during each loading and unloading. Z The average value;

[0133] (III) The torsion calibration coefficient is δ

[0134] M is the change in strain gauge signal used to measure torque during each loading and unloading. X The average value;

[0135] Bending moment calibration factor δ V The shear force calibration factor is δ F The torsion calibration coefficient δ is the vertical bending moment, shear force, and torsion calibration coefficient of the measuring beam (3). Among the calibration coefficients in this set, the bending moment calibration coefficient δ V and the shear force calibration factor is δ F The vertical calibration coefficient for measuring beam 3.

[0136] Step 5: Recalibrate the horizontal bending moment calibration coefficient δ of beam (3) again. V and shear force calibration coefficient δ F :

[0137] (I) Reinstallation of measuring beam 3:

[0138] Release the clamping and fixing device 10 from fixing the measuring beam 3, rotate and flip the measuring beam 3 around the axis by 90 degrees, so that the bottom of the measuring beam 3 is set vertically, and then the upper clamping structure cooperates with the measuring beam 3 to clamp the measuring beam 3, so that the measuring beam 3 maintains a fixed position during the measurement process;

[0139] (II) Measurement Preparation:

[0140] The frame structure 20 is re-fixed at the original installation location;

[0141] According to the test requirements, strain gauges were attached to the corresponding positions of the measuring beam 3. During the test, strain signals at various positions of the measuring beam 3 were obtained through the strain gauges.

[0142] The first weight set 41 is suspended at one end of the upper frame piece 21 of the installed frame structure 20, and the second weight set 42 is suspended at one end of the lower frame piece 22 of the installed frame structure 20. The first weight set 41 and the second weight set 42 are located on both sides of the frame structure 20, respectively. The horizontal distance from the suspension point of the first weight set 41 and the second weight set 42 to the center of the cross section of the measuring beam 3 is equal, both being L3, and the suspension points of the first weight set 41 and the second weight set 42 are symmetrical about the center of the cross section of the measuring beam 3.

[0143] Each strain gauge is connected to a dynamic strain gauge to obtain the signal of each strain gauge during the calibration process;

[0144] (III) Obtain the strain gauge signal change ε ​​of the measuring beam 3 for measuring bending moment using the same method. V The change in strain gauge signal F used to measure shear force Z .

[0145] (iv) Calculate and obtain the calibration coefficient of measuring beam 3:

[0146] When a weight of mass m is loaded in a single load, the vertical bending moment on the measuring section S is M = 2mgL2 and the shear force on the measuring section S is F = 2mg, the torque on the measuring section S is T = 2mgL3, and g is the acceleration due to gravity.

[0147] The bending moment calibration factor is δ V :

[0148] ε is the change in strain gauge signal used to measure bending moment during each loading and unloading. V The average value;

[0149] The shear force calibration factor is δ F :

[0150] F is the change in strain gauge signal used to measure shear force during each loading and unloading. Z The average value;

[0151] The bending moment calibration coefficient δ obtained in step 5 V The shear force calibration factor is δ F This is the calibration coefficient for the horizontal direction of the measuring beam (3).

[0152] In the calibration method of the measuring beam calibration device, equal and variable forces are applied to both sides of the measuring beam 3, enabling the calibration of bending moment, shear force, and torque of the measuring beam without disassembling the load loading fixture. Since equal and opposite forces are applied to both sides of the measuring beam 3 when the load is applied, the external load on the measuring beam 3 is only torque, thereby avoiding interference from bending moment and shear force on the torque signal, minimizing uncertainties in the torque coefficient calibration process, and improving the calibration accuracy of the torque coefficient.

[0153] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. A calibration device for a large-size measuring beam, characterized in that: The device includes a clamping and fixing device (10), the side of which is connected to a fixed base (6). The clamping and fixing device (10) includes a lower fixing plate (12) and an upper pressing structure, which are respectively connected to the fixed base (6). A measuring beam (3) is placed on the upper surface of the lower fixing plate (12). The upper pressing structure cooperates with the upper part of the measuring beam (3) to fix the measuring beam (3). A frame structure (20) is installed on the measuring beam (3) on one side of the clamping and fixing device (10). The frame structure (20) is used to connect the loaded weight (40). It also includes a pulley structure (50) that works in conjunction with the loaded weight (40); The frame structure (20) consists of an upper frame member (21) and a lower frame member (22) arranged in parallel and staggered configurations. The upper frame member (21) and the lower frame member (22) have the same structure and are symmetrical about the center of the cross section of the measuring beam (3). An adjustment groove (2103) is provided through the middle of the upper surface of the upper frame member (21). The adjustment grooves (2103) of the upper frame member (21) and the lower frame member (22) correspond vertically. At the same time, a pair of long screw assemblies (23) are provided through the adjustment grooves (2103) of the upper frame member (21) and the lower frame member (22). The two ends of the long screw assemblies (23) are respectively connected to the upper frame member (21). The upper frame (21) and the lower frame (22) are combined with the lower frame (22) to form a ring structure with a pair of long screw assemblies (23). The inside of the ring structure is in conjunction with the outer periphery of the cross section of the measuring beam (3). The loaded weight (40) includes a first weight group (41) suspended at one end of the upper frame (21) and a second weight group (42) suspended at one end of the lower frame (22). The first weight group (41) and the second weight group (42) are located on both sides of the frame structure (20). The horizontal distance between the suspension point of the first weight group (41) and the second weight group (42) and the center of the cross section of the measuring beam (3) is equal. When the load (40) acts alone, bending moment and shear load are applied to the measuring beam (3) for the calibration of bending moment and shear force of the measuring beam (3); When the loaded weight (40) is used in conjunction with the pulley structure (50), the first weight group (41) is connected to the upper frame piece (21) through a flexible connecting line. The flexible connecting line is in conjunction with the fixed pulley (51) at the upper end of the pulley structure (50). The flexible connecting lines on both sides of the fixed pulley (51) are parallel to each other. By changing the direction of the applied load, torque is applied to the measuring beam (3) for the torque calibration of the measuring beam (3).

2. The large-size measuring beam calibration device as described in claim 1, characterized in that: The structure of the upper clamping structure is as follows: it includes a movable plate (13) that cooperates with the upper part of the measuring beam (3), an upper fixed plate (11) is provided above the movable plate (13), the side of the upper fixed plate (11) is connected to the fixed base (6), and a clamping adjustment component (14) that cooperates with the movable plate (13) is provided on the upper fixed plate (11). The clamping adjustment component (14) is used to adjust the relative distance between the movable plate (13) and the upper fixed plate (11) so that the movable plate (13) cooperates with the measuring beam (3).

3. The large-size measuring beam calibration device as described in claim 2, characterized in that: The upper fixing plate (11) has the same structure as the lower fixing plate (12). The upper fixing plate (11) has the following structure: it includes a fixing base plate (1101). One end of the fixing base plate (1101) is perpendicular to the upper surface of the fixing base plate (1101) and is provided with a plate-shaped mounting part (1102). The mounting part (1102) has a mounting hole (1103) and cooperates with the fixing base (6).

4. The large-size measuring beam calibration device as described in claim 3, characterized in that: The upper fixing plate (11) has a plurality of threaded holes (1104) on its fixing base plate (1101). The clamping adjustment member (14) is a fastener that is threadedly engaged with the threaded hole (1104). One end of the clamping adjustment member (14) passes through the threaded hole (1104) and engages with the upper surface of the movable plate (13).

5. The large-size measuring beam calibration device as described in claim 1, characterized in that: The structure of the pulley structure (50) is as follows: it includes a pulley bracket (52), the upper part of which is rotatably connected to a fixed pulley (51), and the flexible connecting line between the frame structure (20) and the loaded weight (40) is in cooperation with the fixed pulley (51).

6. A calibration method using the large-size measuring beam calibration device as described in any one of claims 1-5, characterized in that: Includes the following steps: Step 1: Install the measuring beam (3): The clamping and fixing device (10) is connected to the fixed base (6). The initial relative position of the lower fixing plate (12) and the upper pressing structure is adjusted so that the measuring beam (3) can be placed between the lower fixing plate (12) and the upper pressing structure. At the same time, the lower fixing plate (12) plays the role of supporting the measuring beam (3). Then, the upper pressing structure is used to clamp the measuring beam (3) so that the measuring beam (3) remains fixed in position during the measurement process. Step 2: Measurement Preparation Determine the location of the measurement profile (S) and the installation location of the frame structure (20). The measurement profile (S) is located between the frame structure (20) and the clamping and fixing device (10). The distance between the measurement profile (S) and the clamping and fixing device (10) is L1, and the distance between the frame structure (20) and the measurement profile (S) is L2. According to the test requirements, strain gauges were attached to the corresponding positions of the measuring beam (3), and strain signals at each position of the measuring beam (3) were obtained through the strain gauges during the test. The first weight group (41) is suspended at one end of the upper frame piece (21) of the installed frame structure (20), and the second weight group (42) is suspended at one end of the lower frame piece (22) of the installed frame structure (20). The first weight group (41) and the second weight group (42) are located on both sides of the frame structure (20). The horizontal distance between the suspension point of the first weight group (41) and the second weight group (42) and the center of the cross section of the measuring beam (3) is equal, both being L3. The suspension points of the first weight group (41) and the second weight group (42) are symmetrical about the center of the cross section of the measuring beam (3). Each strain gauge is connected to a dynamic strain gauge to obtain the signal of each strain gauge during the calibration process; Step 3: Obtain the strain signal changes at various locations on the measuring beam (3): (i) Obtaining the change in strain gauge signal for measuring bending moment : Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first weight group (41) and the second weight group (42), and then simultaneously and sequentially unloaded, ensuring that the magnitude and direction of the force applied to the first weight group (41) and the second weight group (42) are equal, and the change in strain gauge signal used to measure bending moment is obtained during each loading and unloading. ; (ii) Obtaining the strain gauge signal change for measuring shear force : Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first weight group (41) and the second weight group (42), and then the weight of mass m is simultaneously and sequentially unloaded, ensuring that the magnitude and direction of the force applied by the first weight group (41) and the second weight group (42) are equal, and the change in the strain gauge signal used to measure the shear force is obtained during each loading and unloading. ; (iii) Change in strain gauge signal used to measure torque Each time, a weight of mass m is simultaneously and sequentially loaded at the corresponding positions of the first weight group (41) and the second weight group (42), and then the weight of mass m is simultaneously and sequentially unloaded, ensuring that the forces applied to the first weight group (41) and the second weight group (42) are equal in magnitude and opposite in direction, thereby obtaining the change in the signal of the strain gauge used to measure the torque during each loading and unloading. ; Step 4: Calculate and obtain the calibration coefficient of the measuring beam (3): When a weight of mass m is applied in a single load, the vertical bending moment borne by the measurement profile (S) is: The shear forces borne by the measured profile (S) are respectively The torque borne by the measured profile (S) is g is the acceleration due to gravity; (a) The bending moment calibration factor is : , The change in strain gauge signal used to measure bending moment during each loading and unloading. The average value; (ii) The shear force calibration factor is : = , The change in strain gauge signal used to measure shear force during each loading and unloading. The average value; (iii) The torsion calibration coefficient is : , The change in strain gauge signal used to measure torque during each loading and unloading. The average value; Bending moment calibration factor The shear force calibration factor is and torsional calibration coefficient is That is, the calibration coefficient of the measuring beam (3).

7. The calibration method as described in claim 6, characterized in that: In the third step: the forces applied to the first weight group (41) and the second weight group (42) are equal in magnitude and opposite in direction. This is achieved by extending the flexible connecting line between the first weight group (41) and the hanging point of the first weight group (41) vertically upward and passing it around the fixed pulley (51) so that the first weight group (41) hangs down naturally. At the same time, the second weight group (42) hangs down naturally after being connected to the hanging point of the second weight group (42) through the flexible connecting line.

8. The calibration method as described in claim 6, characterized in that: After completing the calibration operations from step one to step four, remove the measuring beam (3) from the clamping and fixing device (10), and at the same time remove the frame structure (20). Rotate the measuring beam 90 degrees around the axis and repeat the calibration operations from step one to step four.

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