A calibration device and method for a resistance strain displacement sensor

Abstract

The present application belongs to the technical field of sensor detection equipment, and discloses a kind of calibration device and method of resistance strain type displacement sensor, calibration device includes force support, fulcrum support, fulcrum spring piece, beam, lower center block and upper center block, fulcrum support is oppositely arranged with force support, one end of beam is connected to fulcrum support by fulcrum spring piece, and the other end is connected with force support;Upper center block is connected with lower center block, and both are respectively provided with first semicircular cone convex and second semicircular cone convex, first semicircular cone convex and second semicircular cone convex are oppositely spaced;Lower center block is slidably connected with beam;Force support is used to drive one end of beam to move up and down, so that second semicircular cone convex or first semicircular cone convex applies an upward displacement or downward displacement to free end.The present application can reduce displacement feed amount to increase calibration point number, effectively improve the calibration precision and accuracy of resistance strain type displacement sensor.

Description

Technical Field

[0001] This invention belongs to the technical field of sensor detection equipment, and more specifically, relates to a calibration device and method for a resistance strain gauge displacement sensor. Background Technology

[0002] In recent years, with the continuous improvement of detection technology and the rapid development of high-end equipment, the accuracy requirements for sensors have become increasingly stringent. A resistance strain gauge displacement sensor is a displacement measuring device that converts displacement into an electrical signal. It consists of a displacement spring, a strain gauge, and a bridge circuit. When the free end of the displacement spring changes displacement, the strain gauge attached to the surface of the spring will experience strain due to the bending of the spring, causing a change in the resistance value of the strain gauge. This, in turn, changes the output electrical signal of the bridge circuit connected to the strain gauge. By acquiring the change in the output electrical signal and based on the correspondence between the input displacement at the free end of the displacement spring and the output electrical signal, the magnitude of the input displacement can be determined from the magnitude of the output electrical signal. Resistance strain gauge displacement sensors have advantages such as high accuracy, small size, convenient installation, and easy acquisition and processing of output signals. Therefore, they are widely used in aerospace, precision instruments, and other structures with high precision requirements and limited space.

[0003] Sensor calibration is a crucial step in ensuring the accuracy and precision of sensors. The calibration of a resistance strain gauge displacement sensor involves establishing a correspondence between the input displacement at the free end of the displacement spring and the output electrical signal of the bridge circuit using a specific calibration device. Research has found that existing calibration devices for resistance strain gauge displacement sensors typically apply a single displacement directly to the free end of the displacement spring. However, the incremental displacement changes are relatively large, limiting the number of calibration points and severely impacting the accuracy and precision of the sensor calibration. Summary of the Invention

[0004] In view of the above-mentioned defects or improvement needs of the prior art, the present invention provides a calibration device and method for a resistance strain gauge displacement sensor, which can reduce the displacement feed amount to increase the number of calibration points, effectively improving the calibration accuracy and precision of the resistance strain gauge displacement sensor.

[0005] To achieve the above objectives, according to one aspect of the present invention, a calibration device for a resistance strain gauge displacement sensor is provided. The calibration device includes a force-applying support, a fulcrum support, a fulcrum spring, a beam, a lower center block, and an upper center block. The fulcrum support and the force-applying support are disposed opposite to each other. One end of the beam is connected to the fulcrum support via the fulcrum spring, and the other end is connected to the force-applying support. The upper center block and the lower center block are connected, and each is provided with a first semi-conical protrusion and a second semi-conical protrusion, which are spaced apart from each other to accommodate the free end of the displacement spring of the resistance strain gauge displacement sensor under test. The lower center block is slidably connected to the beam. The force-applying support is used to drive one end of the beam to move up and down, so that the second semi-conical protrusion or the first semi-conical protrusion applies an upward displacement or a downward displacement to the free end.

[0006] Furthermore, the beam has a dovetail groove; the lower center block is U-shaped and has a first through groove. The bottom surface of the first through groove has a dovetail protrusion, which is located in the dovetail groove, forming a sliding connection between the two, thereby making the lower center block and the beam slide together; the two opposite groove walls of the first through groove are respectively provided with second threaded through holes, each second threaded through hole is threaded with a locking screw, and the two locking screws are arranged opposite each other. By rotating the two locking screws, the beam is held in place, so that the lower center block is fixed on the beam.

[0007] Furthermore, the upper center block is L-shaped and includes a first support plate and a second support plate connected vertically. One end of the second support plate is fixedly connected to the outer surface of the lower center block. The first support plate is parallel to the bottom surface of the first through groove. A first semi-conical protrusion is disposed on the surface of the first support plate facing the lower center block. The axes of the first semi-conical protrusion and the second semi-conical protrusion coincide, and their cone apexes face each other.

[0008] Furthermore, the force-applying support has a first boss and a second boss fixed at intervals on the side facing the fulcrum support; the first boss and the second boss are respectively provided with a first threaded through hole and a second threaded through hole, the upper force-applying screw is threaded to the first threaded through hole, and the lower force-applying screw is threaded to the second threaded through hole; the other end of the beam is located between the upper force-applying screw and the lower force-applying screw, and its two opposing surfaces are in contact with the upper force-applying screw and the lower force-applying screw respectively; by adjusting the upper force-applying screw or the lower force-applying screw, the free end of the displacement spring is subjected to a downward displacement by the upper center block or an upward displacement by the lower center block.

[0009] Furthermore, the calibration device also includes a first guide rail, a second guide rail, a first slider, a second slider, a lifting platform support, a lifting platform fixing component, and a lifting platform movable component. The first guide rail and the second guide rail are arranged in parallel. The first slider and the second slider are slidably arranged on the first guide rail and the second guide rail, respectively. The lifting platform support is fixedly connected to the first slider and the second slider, respectively. The lifting platform fixing component is fixedly connected to the lifting platform support. The lifting platform movable component is movably connected to the lifting platform fixing component and can move up and down in the vertical direction. The fixed end of the displacement spring is fixedly connected to the lifting platform movable component.

[0010] Furthermore, the calibration device also includes a second locking block and a third locking block, which are respectively disposed on the second guide rail and located on opposite sides of the second slider; the second locking block and the third locking block fix the position of the second slider by being locked on the second guide rail.

[0011] Furthermore, the lifting platform fixing component is fixed on the lifting support, and a first vertical plate and a second vertical plate are provided thereon. The first vertical plate is arranged along the length direction of the first guide rail, and the second vertical plate is arranged along the length direction perpendicular to the first guide rail. A guide groove is provided on the side of the first vertical plate away from the second vertical plate. The lifting platform fixing component forms a sliding connection with the moving part of the lifting platform through the guide groove, so that the moving part of the lifting platform can slide up and down along the guide groove. A cylindrical shaft is provided on the other side of the first vertical plate, and a rotating block is arranged on the cylindrical shaft, which can rotate around the cylindrical shaft. The rotating block is V-shaped and includes a first page and a second page connected to each other. The second vertical plate has an internally threaded through hole, and a screw rod forms a threaded connection with the internally threaded through hole. The second page contacts one end of the screw rod.

[0012] Furthermore, the movable component of the lifting platform is T-shaped, and a cylindrical protrusion is provided on one end of its base plate. The cylindrical protrusion contacts the first page. By rotating the inner ring of the screw rod, the inner ring of the screw rod moves forward or backward, thereby driving the rotating block to rotate, so as to drive the movable component of the lifting platform to slide up or down.

[0013] Furthermore, the other end of the substrate is fixedly connected to one end of the tension spring, and the other end of the tension spring is fixedly connected to the lifting platform fixing component; the sensor support is fixed on the substrate, and the laser displacement sensor is disposed on the sensor support; the laser beam emitted by the laser displacement sensor irradiates the free end.

[0014] The present invention also provides a calibration method for a resistance strain gauge displacement sensor, wherein the calibration method uses the calibration device for the resistance strain gauge displacement sensor described above to calibrate the resistance strain gauge displacement sensor.

[0015] In summary, compared with the prior art, the calibration device and method for resistance strain gauge displacement sensors provided by the present invention have the following advantages:

[0016] 1. This invention reduces a large displacement into a small displacement by means of a displacement reduction mechanism, which is then applied to the displacement spring of the resistance strain gauge displacement sensor. The displacement spring feeds a small amount of displacement each time, and the number of calibration points is large, which effectively improves the calibration accuracy and precision.

[0017] 2. By adjusting the position of the lower center block to change the minimum displacement, the calibration of resistance strain gauge displacement sensors with different accuracy requirements can be achieved, and the operation is simple.

[0018] 3. The upper center block can apply downward displacement to the displacement spring, and the lower center block can apply upward displacement to the displacement spring, realizing bidirectional calibration of the resistance strain gauge displacement sensor. Moreover, the same set of devices is used to apply displacement during bidirectional calibration, and the same set of devices is used for displacement detection, resulting in good consistency of bidirectional calibration accuracy.

[0019] 4. The reed support is detachably connected to the moving parts of the lifting platform. For different models of resistance strain gauge displacement sensors, simply attach them to the same reed support, remove the original reed support, and install the reed support with the other model of resistance strain gauge displacement sensor attached. This allows for quick and accurate calibration of different models of resistance strain gauge displacement sensors. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a calibration device for a resistance strain gauge displacement sensor provided by the present invention;

[0021] Figure 2 yes Figure 1 A schematic diagram of the position adjustment mechanism of the calibration device for a resistance strain gauge displacement sensor.

[0022] Figure 3 yes Figure 1 A schematic diagram of the beam of the calibration device for a resistance strain gauge displacement sensor in China;

[0023] Figure 4 yes Figure 1 A schematic diagram of the components of the calibration device for a resistance strain gauge displacement sensor, consisting of an upper center block, a lower center block, and a locking screw.

[0024] Figure 5yes Figure 1 A magnified view of a portion of the displacement spring in the calibration device of a resistance strain gauge displacement sensor, showing the upper surface of the spring contacting the cone apex of the semi-conical protrusion of the upper center block.

[0025] Figure 6 yes Figure 1 A magnified view of a portion of the displacement spring in the calibration device of a resistance strain gauge displacement sensor, showing the lower surface of the spring contacting the conical protrusion of the lower center block.

[0026] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein: 1-base plate, 21-fulcrum support, 22-force application support, 221-upper force application screw, 222-lower force application screw, 23-fulcrum spring, 24-first locking block, 25-beam, 251-lower center block, 252-upper center block, 253-locking screw, 311-first guide rail, 312-second guide rail, 321-first slider, 322-second slider, 331-second locking block, 332-third locking block, 34-lifting platform support, 35-lifting platform fixing component, 351-tension spring, 352-screw rod, 353-rotating block, 36-lifting platform moving component, 41-displacement spring, 42-strain gauge, 43-spring support, 51-laser displacement sensor, 52-sensor support. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0028] Please see Figure 1 , Figure 2 , Figure 3 and Figure 4 The present invention provides a calibration device for a resistance strain gauge displacement sensor. The calibration device enables the free end of the displacement spring 41 to generate a bidirectional high-precision small displacement, thereby realizing bidirectional calibration of the resistance strain gauge displacement sensor. It is simple to install, easy to operate, and effectively improves the accuracy and precision of the resistance strain gauge displacement sensor calibration.

[0029] The calibration device includes a base plate 1, a displacement reduction mechanism, a position adjustment mechanism, and a laser displacement sensor 51. Both the displacement reduction mechanism and the position adjustment mechanism are mounted on the base plate 1, and the laser displacement sensor 51 is mounted on the position adjustment mechanism. The position adjustment mechanism also supports the resistance strain gauge displacement sensor to be calibrated.

[0030] The base plate 1 is generally rectangular, with a hollow groove in its center to reduce its weight. Threaded holes are formed at both ends of the base plate 1 opposite to the hollow groove. These threaded holes are for engaging screws to mount the displacement reduction mechanism and the position adjustment mechanism onto the base plate 1. A screw mounting hole is machined at each of the four corners of the base plate 1 to mount it onto the worktable. A one-millimeter boss is provided around each of the threaded holes and screw mounting holes to improve the machinability of the parts and ensure machining progress and assembly accuracy.

[0031] The position adjustment mechanism includes a first guide rail 311, a second guide rail 312, a first slider 321, a second slider 322, a second locking block 331, a third locking block 332, a lifting platform support 34, a lifting platform fixing component 35, a tension spring 351, a spiral rod 352, a rotating block 353, and a lifting platform movable component 36. The position adjustment mechanism is used to adjust the vertical position of the laser displacement sensor 51 and the resistance strain gauge displacement sensor.

[0032] The first guide rail 311 and the second guide rail 312 are fixedly fixed to the base plate 1 at intervals and located on one side of the hollow groove. Specifically, the first guide rail 311 and the second guide rail 312 are fixed to the base plate 1 by screws. The first slider 321 is slidably disposed on the first guide rail 311, and the second slider 322 is slidably disposed on the second guide rail 312. The two opposite ends of the lifting platform support 34 are respectively fixed to the first slider 321 and the second slider 322, so that the relative position between the first slider 321 and the second slider 322 does not change.

[0033] The second locking block 331 and the third locking block 332 are respectively disposed on the second guide rail 312 and located on opposite sides of the second slider 322. The second locking block 331 and the third locking block 332 can lock the second slider 322 in place by engaging with the second guide rail 312 or move with the second slider 322 to allow the second slider 322 to reach the target position. In this embodiment, both the second locking block 331 and the third locking block 332 are made of elastic material, which can engage with the second guide rail 312 to prevent sliding and prevent the second slider 322 from sliding; since the first slider 321 and the second slider 322 are fixedly connected together by the lifting platform support 34, when the second slider 322 is limited and fixed, the first slider 321 can no longer slide.

[0034] The lifting platform fixing component 35 is fixed to the lifting support, and a first vertical plate and a second vertical plate are provided thereon. The first vertical plate is arranged along the length direction of the first guide rail 311, and the second vertical plate is arranged along the length direction perpendicular to the first guide rail 311. A guide groove is provided on the side of the first vertical plate away from the second vertical plate. The lifting platform fixing component 35 is slidably connected to the lifting platform movable component 36 through the guide groove, so that the lifting platform movable component 36 can slide up and down along the guide groove. A cylindrical shaft is provided on the other side of the first vertical plate, and the rotating block 353 is disposed on the cylindrical shaft and can rotate around the cylindrical shaft. In this embodiment, the rotating block 353 is V-shaped and includes a first page and a second page connected to each other. The second vertical plate has an internally threaded through hole, and the spiral rod 352 is threadedly connected to the internally threaded through hole. The outer ring of the screw rod 352 is fixed by engaging the external thread on its outer surface with the internal thread in the internal threaded through hole of the lifting platform fixing member 35. The inner ring of the screw rod 352 can move back and forth relative to the outer ring by rotation. The second page is in contact with one end of the screw rod 352.

[0035] The movable component 36 of the lifting platform is T-shaped, with a cylindrical protrusion on one end of its base plate, which contacts the first page. The other end of the base plate is fixedly connected to one end of the tension spring 351, and the other end of the tension spring 351 is fixedly connected to the lifting platform fixing component 35 to ensure that the movable component 36 of the lifting platform remains stable during sliding. Specifically, rotating the inner ring of the screw rod 352 causes it to move forward or backward, thereby driving the rotating block 353 to rotate, which in turn causes the movable component 36 of the lifting platform to slide upward or downward.

[0036] The reed support 43 and the sensor support are respectively fixed on the base plate, and the laser displacement sensor 51 is disposed on the sensor support. Specifically, the base plate is provided with a threaded hole, which cooperates with a screw to fix the reed support 43 and the sensor support on the base plate.

[0037] The displacement reduction mechanism includes a fulcrum support 21, a force-applying support 22, an upper force-applying screw 221, a lower force-applying screw 222, a fulcrum spring 23, a first locking block 24, a beam 25, a lower center block 251, an upper center block 252, and a locking screw 253.

[0038] The fulcrum support 21 and the force-applying support 22 are respectively fixed to the base plate 1 and located at opposite ends of the hollow groove. The two ends of the fulcrum spring 23 are respectively fixedly connected to one end of the beam 25 and the fulcrum support 21 via first locking blocks 24, allowing the beam 25 to rotate around the fulcrum support 21 at a small angle. Specifically, one side of the fulcrum support 21 has two threaded holes, one end of the beam 25 also has two threaded holes, the fulcrum spring 23 has four through holes, and each first locking block 24 has two through holes. One end of the fulcrum spring 23 is fixed between one first locking block 24 and the beam 25 by two screws, and the other end is fixed between another first locking block 24 and the fulcrum support 21 by two other screws.

[0039] The force-applying support 22 has a first boss and a second boss fixed at intervals on the side facing the fulcrum support 21. The first boss and the second boss are respectively provided with a first threaded through hole and a second threaded through hole. The upper force-applying screw 221 is threaded to the first threaded through hole, and the lower force-applying screw 222 is threaded to the second threaded through hole. The other end of the beam 25 is located between the upper force-applying screw 221 and the lower force-applying screw 222, and its two opposing surfaces are in contact with the upper force-applying screw 221 and the lower force-applying screw 222, respectively.

[0040] The beam 25 has a dovetail groove along its length, which forms a sliding connection with the lower center block 251. The lower center block 251 is connected to the upper center block 252. The lower center block 251 is U-shaped and has a first through groove. The bottom surface of the first through groove has a dovetail-shaped protrusion, which is located within the dovetail groove, forming a sliding connection between the two, thereby allowing a sliding connection between the lower center block 251 and the beam 25. Two threaded through holes are respectively formed on the two opposite walls of the first through groove. Each second threaded through hole is threaded with a locking screw 253. The two locking screws 253 are arranged opposite each other, pressing against the beam 25, thus fixing the lower center block 251 to the beam 25 and preventing it from sliding relative to the beam 25.

[0041] The outer peripheral surface of the lower center block 251 is further provided with a second semi-conical protrusion, which is located on opposite sides of the bottom of the first through groove, as well as the dovetail protrusion. The upper center block 252 is L-shaped and includes a first support plate and a second support plate connected vertically. One end of the second support plate is fixedly connected to the outer surface of the lower center block 251. The first support plate is parallel to the bottom surface of the first through groove. A first semi-conical protrusion is provided on the surface of the first support plate facing the lower center block 251. The axes of the first semi-conical protrusion and the second semi-conical protrusion coincide, their cone apexes face each other, and there is a certain distance between them.

[0042] The resistance strain gauge displacement sensor is the device to be calibrated. It includes a displacement spring 41 and strain gauges 42. The displacement spring 41 has a fixed end and a free end connected to each other. A strain gauge 42 is respectively disposed on two opposite surfaces of the spring 41. The two strain gauges 42 are symmetrically arranged and fixed to the displacement spring 41 with glue. The fixed end is fixedly connected to the spring support 43 with glue. The laser beam emitted by the laser displacement sensor 51 irradiates the free end.

[0043] After the calibration device is installed, the free end of the displacement spring 41 is located between the first semi-conical protrusion and the second semi-conical protrusion. Adjusting the screw rod 352 can make the displacement spring 41 move up and down, and make the free end contact the cone tip of the first semi-conical protrusion or the second semi-conical protrusion. Adjusting the upper force screw 221 or the lower force screw 222 can make the free end of the displacement spring 41 be subjected to a downward displacement by the upper center block 252 or an upward displacement by the lower center block 251.

[0044] The strain gauge 42 is connected to a bridge circuit board or a resistance strain gauge via a pre-existing lead wire. When the free end of the displacement spring 41 generates an upward or downward input displacement X, the laser displacement sensor 51 displays the value of the input displacement X. The upper and lower surfaces of the displacement spring 41 will be stretched or compressed, and the strain gauge 42 attached to the upper and lower surfaces of the displacement spring 41 will also be stretched or compressed, causing the bridge circuit board and the resistance strain gauge connected to the strain gauge 42 to generate an output voltage U. The calibration device also includes a processor, which performs fitting processing on the displacement X and the output voltage U to obtain the relationship between the output voltage U and the input displacement X, thus completing the calibration of the resistance strain gauge displacement sensor.

[0045] This invention also provides a calibration method for a resistance strain gauge displacement sensor. The calibration method uses the calibration device for the resistance strain gauge displacement sensor described above to calibrate the sensor, and specifically includes the following steps:

[0046] (1) Start the laser displacement sensor 51.

[0047] (2) Slide the lower center block 251 to determine its position according to the different calibration accuracy requirements. The higher the calibration accuracy requirement and the smaller the minimum displacement feed, the closer the lower center block 251 is to the fulcrum support 21. Conversely, the lower the calibration accuracy requirement and the larger the minimum displacement feed, the closer the lower center block 251 is to the force application support 22. After the lower center block 251 moves to the target position, tighten the locking screw 253 to lock the lower center block 251, preventing it from sliding along the beam 25.

[0048] (3) Slide the first slider 321 and the second slider 322 so that the free end of the displacement spring 41 is located between the cone tops of the upper and lower center blocks 251, and the laser emitted by the laser displacement sensor 51 will not be blocked by the upper center block 252 to irradiate the free end of the displacement spring 41.

[0049] (4) Twist the screw rod 352 to move the displacement spring 41 upward. Stop twisting when the free end of the displacement spring 41 just contacts the cone tip of the upper center block 252. Figure 5 As shown, the output voltage of the bridge circuit board or resistance strain gauge is zero at this time.

[0050] (5) Tighten the upper force screw 221 and the lower force screw 222 simultaneously to move them downwards. The beam 25 rotates downwards, the upper center block 252 moves downwards, and the free end of the displacement spring 41 bends downwards under the action of the cone tip of the upper center block 252. When the reading of the laser displacement sensor 51 increases by a target displacement feed amount ΔX, stop tightening the upper force screw 221 and the lower force screw 222, and record the output voltage value U of the bridge circuit board or the resistance strain gauge at this time. 11 .

[0051] (6) Based on the required number of calibrated points n1, repeat the previous step to obtain data points (ΔX, U) with a one-to-one correspondence. 11 (2ΔX, U) 12 (3ΔX, U) 13 ), ..., (n1ΔX, U 1n1 There are a total of n1 items.

[0052] (7) Tighten the upper force screw 221 and the lower force screw 222 to move upward until the beam 25 returns to a balanced state.

[0053] (8) Twist the screw rod 352 to move the displacement spring 41 downwards. Stop twisting when the free end of the displacement spring 41 just contacts the cone tip of the lower center block 251. Figure 6 As shown, the output voltage of the bridge circuit board or resistance strain gauge is zero at this time.

[0054] (9) Tighten the upper force screw 221 and the lower force screw 222 simultaneously to move them upwards. The beam 25 rotates upwards, the lower center block 251 moves upwards, and the free end of the displacement spring 41 bends upwards under the action of the cone tip of the lower center block 251. When the reading of the laser displacement sensor 51 decreases by one target displacement feed amount ΔX, stop tightening the upper force screw 221 and the lower force screw 222, and record the output voltage value U of the bridge circuit board or the resistance strain gauge at this time. 21 .

[0055] (10) Based on the required number of calibrated points n2, repeat the previous step to obtain data points (-ΔX, U) with a one-to-one correspondence. 21 (-2ΔX, U) 22 (-3ΔX, U) 23 ), ..., (-n2ΔX, U 2n2 There are a total of n2 items.

[0056] (11) Tighten the upper force screw 221 and the lower force screw 222 to move downwards until the beam 25 returns to a balanced state.

[0057] (12) Turn off the laser displacement sensor 51. Fit the relationship curve between the output voltage U and the input displacement X of the resistance strain gauge displacement sensor based on the obtained n1+n2 data points to complete the calibration.

[0058] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A calibration device for a resistance strain gauge displacement sensor, characterized in that: The calibration device includes a force-applying support, a fulcrum support, a fulcrum spring, a beam, a lower center block, and an upper center block. The fulcrum support and the force-applying support are arranged opposite each other. One end of the beam is connected to the fulcrum support via the fulcrum spring, and the other end is connected to the force-applying support. The upper center block and the lower center block are connected, and each is provided with a first semi-conical protrusion and a second semi-conical protrusion, which are spaced apart from each other to accommodate the free end of the displacement spring of the resistance strain gauge displacement sensor to be measured. The lower center block is slidably connected to the beam. The force-applying support is used to drive one end of the beam to move up and down, so that the second semi-conical protrusion or the first semi-conical protrusion applies an upward or downward displacement to the free end. The force-applying support has a first boss and a second boss fixed at intervals on the side facing the fulcrum support; the first boss and the second boss are respectively provided with a first threaded through hole and a second threaded through hole, the upper force-applying screw is threaded to the first threaded through hole, and the lower force-applying screw is threaded to the second threaded through hole; the other end of the beam is located between the upper force-applying screw and the lower force-applying screw, and its two opposing surfaces are in contact with the upper force-applying screw and the lower force-applying screw respectively; by adjusting the upper force-applying screw or the lower force-applying screw, the free end of the displacement spring is subjected to a downward displacement by the upper center block or by the lower center block. An upward displacement; the calibration device further includes a first guide rail, a second guide rail, a first slider, a second slider, a lifting platform support, a lifting platform fixing component, and a lifting platform movable component. The first guide rail and the second guide rail are arranged in parallel. The first slider and the second slider are slidably arranged on the first guide rail and the second guide rail, respectively. The lifting platform support is fixedly connected to the first slider and the second slider, respectively. The lifting platform fixing component is fixedly connected to the lifting platform support. The lifting platform movable component is movably connected to the lifting platform fixing component and can move up and down in the vertical direction. The fixed end of the displacement spring is fixedly connected to the lifting platform movable component.

2. The calibration device for the resistance strain gauge displacement sensor as described in claim 1, characterized in that: The beam has a dovetail groove; the lower center block is U-shaped and has a first through groove. The bottom surface of the first through groove has a dovetail protrusion, which is located in the dovetail groove, forming a sliding connection between the two, thereby making the lower center block and the beam slide together; the two opposite groove walls of the first through groove are respectively provided with second threaded through holes, each of which is threaded with a locking screw. The two locking screws are arranged opposite each other, and by rotating the two locking screws, the beam is held in place, so that the lower center block is fixed on the beam.

3. The calibration device for a resistance strain gauge displacement sensor as described in claim 2, characterized in that: The upper center block is L-shaped and includes a first support plate and a second support plate that are vertically connected. One end of the second support plate is fixedly connected to the outer surface of the lower center block. The first support plate is parallel to the bottom surface of the first through groove. A first semi-conical protrusion is provided on the surface of the first support plate facing the lower center block. The axes of the first semi-conical protrusion and the second semi-conical protrusion coincide, and their cone apexes are opposite each other.

4. The calibration device for a resistance strain gauge displacement sensor as described in claim 1, characterized in that: The calibration device further includes a second locking block and a third locking block, which are respectively disposed on the second guide rail and located on opposite sides of the second slider; the second locking block and the third locking block fix the position of the second slider by being locked on the second guide rail.

5. The calibration device for a resistance strain gauge displacement sensor as described in claim 1, characterized in that: The lifting platform fixing component is fixed on the lifting platform support, and a first vertical plate and a second vertical plate are provided thereon. The first vertical plate is arranged along the length direction of the first guide rail, and the second vertical plate is arranged along the length direction perpendicular to the first guide rail. A guide groove is provided on the side of the first vertical plate away from the second vertical plate. The lifting platform fixing component and the lifting platform movable component are slidably connected through the guide groove, so that the lifting platform movable component can slide up and down along the guide groove. A cylindrical shaft is provided on the other side of the first vertical plate, and a rotating block is arranged on the cylindrical shaft, which can rotate around the cylindrical shaft. The rotating block is V-shaped and includes a first page and a second page connected to each other. The second vertical plate has an internally threaded through hole, and a screw rod is threadedly connected to the internally threaded through hole. The second page is in contact with one end of the screw rod.

6. The calibration device for a resistance strain gauge displacement sensor as described in claim 5, characterized in that: The movable component of the lifting platform is T-shaped, and a cylindrical protrusion is provided on one end of its base plate. The cylindrical protrusion contacts the first page. By rotating the inner ring of the screw rod, the inner ring of the screw rod moves forward or backward, thereby driving the rotating block to rotate, so as to drive the movable component of the lifting platform to slide up or down.

7. The calibration device for a resistance strain gauge displacement sensor as described in claim 6, characterized in that: The other end of the substrate is fixedly connected to one end of the tension spring, and the other end of the tension spring is fixedly connected to the lifting platform fixing component; the sensor support is fixed on the substrate, and the laser displacement sensor is set on the sensor support; the laser beam emitted by the laser displacement sensor irradiates the free end.

8. A calibration method for a resistance strain gauge displacement sensor, characterized in that: The calibration method uses the calibration device of the resistance strain gauge displacement sensor according to any one of claims 1-7 to calibrate the resistance strain gauge displacement sensor.

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