Fiber bragg grating strain gauge

Abstract

The utility model relates to the technical field of strain gauges, in particular to a fiber bragg grating strain gauge, which is characterized in that pressure reduction parts are fixedly arranged on the lower surface of an upper support and the upper surface of a lower support, a strain gauge body is placed between the upper support and the lower support, and the upper support and the lower support are connected through screws; the pressure reduction part absorbs the pressure of the upper bracket and the lower bracket on the strain gauge, and increases the friction factor between the upper bracket and the strain gauge and between the lower bracket and the strain gauge; the pressure reduction body is compressed to deform, so that relative displacement of the strain gauge and the support seat is prevented, partial pressure of the support seat on the strain gauge is absorbed, and the problems that the strain gauge is crushed and the service life of the strain gauge is shortened due to overlarge pressure are prevented; the ribs deform along with the pressure reduction body, more pressure of the support seat is consumed, and the anti-slip sheets are extruded and attached together; the contact area with the strain gauge is increased, the friction force between the strain gauge and the support seat is increased, relative displacement between the strain gauge and the support seat is prevented, and the measurement accuracy is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of strain gauges, in particular to a fiber grating strain gauge. Background Art

[0002] Fiber Bragg Grating (FBG) strain gauge is a sensing device based on fiber Bragg Grating (FBG) technology, which is mainly used to measure the strain in the structure. The working principle of fiber Bragg grating strain gauge is based on the change of the reflected wavelength of the Bragg grating. FBG is a section of doped optical fiber in which the refractive index changes periodically along the axial direction of the optical fiber, forming a grating that reflects light of a specific wavelength. When the optical fiber is subjected to external stress, the refractive index and spacing of the grating area will change, causing the Bragg wavelength (λ_Bragg) to shift. This change in wavelength can be directly corresponded to the amount of strain, so the strain in the structure can be determined by measuring the change in the Bragg wavelength. FBG sensors have been widely used in civil engineering, aerospace, bridges, dams, building monitoring and other fields due to their high precision, good stability, small size and light weight.

[0003] The fiber Bragg grating strain gauge is fixed to the measured structure by a bracket and screws. The bracket clamps the fiber Bragg grating strain gauge therein, and then the bracket is tightened by screws to clamp the fiber Bragg grating strain gauge. The bracket is in direct contact with the fiber Bragg grating strain gauge. If the clamping force of the bracket on the fiber Bragg grating strain gauge is too small, the fiber Bragg grating strain gauge will be displaced, resulting in inaccurate measurement results. If the clamping force of the bracket on the fiber Bragg grating strain gauge is too large, the fiber Bragg grating strain gauge will be deformed, affecting its service life. Utility Model Content

[0004] The main purpose of the utility model is to provide a fiber Bragg grating strain gauge to solve the problems proposed in the related art that the bracket is in direct contact with the fiber Bragg grating strain gauge, which causes the fiber Bragg grating strain gauge to shift, resulting in inaccurate measurement results, and the bracket has too much clamping force on the fiber Bragg grating strain gauge, which causes the fiber Bragg grating strain gauge to deform and affects its service life.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the utility model, a fiber Bragg grating strain gauge is provided, comprising a strain gauge body, wherein the strain gauge body is used to measure the strain in the structure, and further comprising: a bracket seat, wherein there are several bracket seats, which are used to fix the strain gauge body on the object to be measured, wherein the bracket seat comprises an upper bracket, a lower bracket and several pressure relief parts, wherein the pressure relief parts are fixedly arranged on the lower surface of the upper bracket and the upper surface of the lower bracket, wherein the strain gauge body is placed between the upper bracket and the lower bracket, wherein the upper bracket and the lower bracket are connected by screws, and when the screws fix the strain gauge body between the upper bracket and the lower bracket, the pressure relief parts absorb the pressure of the upper bracket and the lower bracket on the strain gauge body, and at the same time increase the friction coefficient between the upper bracket and the lower bracket and the strain gauge body.

[0006] Furthermore, the lower bracket includes a lower bracket body, a lower fixing ring, a plurality of lower connecting blocks and a fixing bar, and the fixing bar is fixedly arranged on the bottom surface of the lower bracket body and protrudes from one side of the lower bracket body.

[0007] Furthermore, the lower fixing ring is fixedly arranged above the lower bracket body and protrudes from one side of the lower bracket body.

[0008] Furthermore, the lower connecting blocks are fixedly arranged on both sides of the top of the lower bracket body and protrude from one side of the lower bracket body, and the lower fixing ring, the lower connecting blocks and the fixing strip are located on the same side of the lower bracket body.

[0009] Furthermore, the upper bracket includes an upper bracket body, an upper fixing ring and a plurality of upper connecting blocks.

[0010] Furthermore, the upper fixing ring is fixedly arranged on the lower surface of the upper bracket body and protrudes from one side of the upper bracket body, the upper connecting blocks are fixedly arranged on both sides of the lower surface of the upper bracket body and protrude from one side of the upper bracket body, and the upper fixing ring and the upper connecting blocks are located on the same side of the upper bracket body.

[0011] Furthermore, the decompression part includes a decompression body, a plurality of ribs and a plurality of anti-slip sheets, the decompression body is in the shape of a hollow prism, and the decompression bodies are fixedly arranged on the lower surface of the upper bracket body and the upper surface of the lower bracket body.

[0012] Furthermore, the ribs are all fixedly arranged on the inner surface of the decompression body, and the anti-slip sheets are all fixedly arranged on the inner surface of the decompression body and are located between adjacent ribs.

[0013] Furthermore, the anti-slip sheet includes a first anti-slip sheet, a second anti-slip sheet and a plurality of notches.

[0014] Furthermore, the first anti-slip sheet is fixedly arranged on the outer surface of the decompression body, the second anti-slip sheet is fixedly arranged on the inner surface of the decompression body, and the notches are both located at the front end of the second anti-slip sheet and inside the decompression body.

[0015] Compared with the prior art, the utility model has the following beneficial effects: when the upper fixing ring and the lower fixing ring squeeze the strain gauge, the decompression body is compressed and deformed, and its inner surface is tightly attached to the outer surface of the strain gauge, preventing the strain gauge and the bracket seat from relative displacement, while absorbing part of the pressure of the bracket seat on the strain gauge, preventing the strain gauge from being crushed by excessive pressure and shortening its service life; the ribs deform together with the decompression body, consuming more pressure from the bracket seat, further protecting the strain gauge from being crushed; the anti-slip sheet is squeezed and fitted together, increasing the contact area with the strain gauge, increasing the friction between the two, preventing the strain gauge and the bracket seat from relative displacement, and ensuring the accuracy of measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is an overall schematic diagram of the utility model;

[0017] Figure 2 This is a schematic diagram of the structure of the bracket seat of the utility model;

[0018] Figure 3 This is a schematic diagram of the upper bracket structure of the utility model;

[0019] Figure 4 This is a schematic diagram of the lower bracket structure of the utility model;

[0020] Figure 5 This is a schematic diagram of the structure of the pressure reducing part of the utility model;

[0021] Figure 6 This is a schematic diagram of the structure of the anti-slip sheet of the utility model.

[0022] Illustration Description:

[0023] 1. Strain gauge body;

[0024] 2. Bracket seat; 21. Upper bracket; 22. Lower bracket; 23. Decompression part; 211. Upper bracket body; 212. Upper fixing ring; 213. Upper connecting block; 221. Lower bracket body; 222. Lower fixing ring; 223. Lower connecting block; 224. Fixing strip; 231. Decompression body; 232. Rib strip; 233. Anti-skid sheet; 2331. First anti-skid sheet; 2332. Second anti-skid sheet; 2333. Notch. DETAILED DESCRIPTION

[0025] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the utility model, the specific implementation method, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0026] See also Figures 1 to 6The present embodiment provides a fiber Bragg grating strain gauge, comprising a strain gauge body 1, and also comprising: a bracket seat 2, wherein the bracket seat 2 has a plurality of bracket seats 2, and the present embodiment preferably has two bracket seats 2, which support and fix the strain gauge body 1 from both ends, and are used to fix the strain gauge body 1 on the object to be measured;

[0027] The bracket seat 2 includes an upper bracket 21, a lower bracket 22 and a plurality of pressure relief portions 23. The pressure relief portions 23 are fixedly arranged on the lower surface of the upper bracket 21 and the upper surface of the lower bracket 22. The strain gauge body 1 is placed between the upper bracket 21 and the lower bracket 22. The upper bracket 21 and the lower bracket 22 are connected by screws. When the screws fix the strain gauge body 1 between the upper bracket 21 and the lower bracket 22, the pressure relief portions 23 absorb the pressure of the upper bracket 21 and the lower bracket 22 on the strain gauge body 1 to prevent the strain gauge body 1 from being crushed. At the same time, the friction coefficient between the upper bracket 21 and the lower bracket 22 and the strain gauge body 1 is increased, and the strain gauge body 1 is fixed in the bracket seat 2 to prevent the strain gauge body 1 and the bracket seat 2 from relative displacement, which affects the measurement result.

[0028] The lower bracket 22 includes a lower bracket body 221, a lower fixing ring 222, a plurality of lower connecting blocks 223 and a fixing bar 224. The fixing bar 224 is fixed to the bottom surface of the lower bracket body 221 and protrudes from one side of the lower bracket body 221. The lower bracket 22 is fixed to the structure to be measured by bolts.

[0029] The lower fixing ring 222 is fixed above the lower bracket body 221 and protrudes from one side of the lower bracket body 221. The lower connecting blocks 223 are fixed on both sides of the top of the lower bracket body 221. In this embodiment, two lower connecting blocks 223 are preferably used to fix the lower bracket body 221 and the upper bracket body 211 together from both ends and protrude from one side of the lower bracket body 221. The lower fixing ring 222, the lower connecting block 223 and the fixing strip 224 are located on the same side of the lower bracket body 221.

[0030] The upper bracket 21 includes an upper bracket body 211, an upper fixing ring 212 and a plurality of upper connecting blocks 213. The upper fixing ring 212 is fixedly arranged on the lower surface of the upper bracket body 211 and protrudes from one side of the upper bracket body 211. The upper connecting blocks 213 are fixedly arranged on both sides of the lower surface of the upper bracket body 211. In this embodiment, two upper connecting blocks 213 are preferably used to fix the lower bracket body 221 and the upper bracket body 211 together from both ends and protrude from one side of the upper bracket body 211. The upper fixing ring 212 and the upper connecting blocks 213 are located on the same side of the upper bracket body 211.

[0031] The decompression part 23 includes a decompression body 231, a plurality of ribs 232 and a plurality of anti-slip sheets 233. The decompression body 231, the ribs 232 and the anti-slip sheets 233 are all made of rubber, which can undergo elastic deformation and have a large friction coefficient, thereby preventing the strain gauge body 1 and the bracket seat 2 from relative displacement. The decompression body 231 is in the shape of a hollow prism, and when it is squeezed and deformed, it spreads to the surroundings, thereby increasing the contact area with the strain gauge body 1. The decompression body 231 is fixedly arranged on the lower surface of the upper bracket body 211 and the upper surface of the lower bracket body 221.

[0032] The ribs 232 are all fixedly arranged on the inner surface of the decompression body 231 to increase the strength of the decompression body 231 and absorb more pressure. The anti-slip sheets 233 are all fixedly arranged on the inner surface of the decompression body 231 and are located between adjacent ribs 232. The anti-slip sheets 233 further strengthen the strength of the decompression body 231 and increase the contact area between the decompression body 231 and the strain gauge body 1.

[0033] The anti-slip sheet 233 includes a first anti-slip sheet 2331, a second anti-slip sheet 2332 and a plurality of notches 2333. The first anti-slip sheet 2331 is fixedly arranged on the outer surface of the decompression body 231, the second anti-slip sheet 2332 is fixedly arranged on the inner surface of the decompression body 231, and the notches 2333 are all located at the front end of the second anti-slip sheet 2332 and inside the decompression body 231. The notches 2333 increase the friction coefficient between the anti-slip sheet 233 and the strain gauge body 1.

[0034] Use bolts to fix the two lower brackets 22 on the object to be measured through the fixing strips 224, and make the two lower brackets 22 be located in the same straight line, put the strain gauge body 1 in the lower fixing rings 222 of the two lower brackets 22, cover the two upper brackets 21 on the corresponding lower brackets 22, align the upper bracket body 211 with the lower bracket body 221, align the upper fixing ring 212 with the lower fixing ring 222, and align the upper connecting block 213 with the lower connecting block 223 respectively, fix the adjacent upper connecting block 213 and the lower connecting block 223 together with screws, so that the upper fixing ring 212 and the lower fixing ring 222 clamp the strain gauge body 1, and as the screws are tightened, the gap between the upper connecting block 213 and the lower connecting block 223 becomes smaller and smaller, and the pressure of the upper fixing ring 212 and the lower fixing ring 222 on the strain gauge body 1 becomes greater and greater, so that the strain gauge body 1 is clamped between the two. , preventing the strain gauge body 1 and the bracket seat 2 from relative displacement, causing the strain gauge body 1 to deviate from the original position and resulting in inaccurate measurement; when the upper fixing ring 212 and the lower fixing ring 222 squeeze the strain gauge body 1, the decompression body 231 is compressed and deformed, and its inner surface is tightly attached to the outer surface of the strain gauge body 1, preventing the strain gauge body 1 and the bracket seat 2 from relative displacement. At the same time, it absorbs part of the pressure of the bracket seat 2 on the strain gauge body 1, preventing the strain gauge body 1 from being crushed by excessive pressure and shortening its service life. The rib 232 deforms together with the decompression body 231, consuming more pressure from the bracket seat 2, further protecting the strain gauge body 1 from being crushed, and the anti-slip sheet 233 is squeezed and fitted together, increasing the contact area with the strain gauge body 1, increasing the friction between the two, preventing the strain gauge body 1 and the bracket seat 2 from relative displacement, and ensuring the accuracy of measurement.

[0035] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A fiber Bragg grating strain gauge, comprising a strain gauge body (1), It is characterized in that Also includes: A support seat (2), wherein the support seat (2) has a plurality of members and is used to fix a strain gauge body (1) on an object to be measured. The support seat (2) comprises an upper support (21), a lower support (22) and a plurality of pressure relief portions (23). The pressure relief portions (23) are all fixedly arranged on the lower surface of the upper support (21) and the upper surface of the lower support (22). The strain gauge body (1) is placed between the upper support (21) and the lower support (22). The upper support (21) and the lower support (22) are connected by screws. When the screws fix the strain gauge body (1) between the upper support (21) and the lower support (22), the pressure relief portions (23) absorb the pressure of the upper support (21) and the lower support (22) on the strain gauge body (1), and at the same time increase the friction coefficient between the upper support (21) and the lower support (22) and the strain gauge body (1).

2. The fiber Bragg grating strain gauge according to claim 1, It is characterized in that The lower bracket (22) comprises a lower bracket body (221), a lower fixing ring (222), a plurality of lower connecting blocks (223) and a fixing strip (224); the fixing strip (224) is fixedly arranged on the bottom surface of the lower bracket body (221) and protrudes from one side of the lower bracket body (221).

3. The fiber Bragg grating strain gauge according to claim 2, It is characterized in that The lower fixing ring (222) is fixedly disposed above the lower bracket body (221) and protrudes from one side of the lower bracket body (221).

4. The fiber Bragg grating strain gauge according to claim 3, It is characterized in that The lower connecting blocks (223) are fixedly arranged on both sides of the top of the lower bracket body (221) and protrude from one side of the lower bracket body (221); the lower fixing ring (222), the lower connecting blocks (223) and the fixing strip (224) are located on the same side of the lower bracket body (221).

5. The fiber Bragg grating strain gauge according to claim 1, It is characterized in that The upper bracket (21) comprises an upper bracket body (211), an upper fixing ring (212) and a plurality of upper connecting blocks (213).

6. The fiber Bragg grating strain gauge according to claim 5, It is characterized in that The upper fixing ring (212) is fixedly arranged on the lower surface of the upper bracket body (211) and protrudes from one side of the upper bracket body (211); the upper connecting blocks (213) are fixedly arranged on both sides of the lower surface of the upper bracket body (211) and protrude from one side of the upper bracket body (211); the upper fixing ring (212) and the upper connecting blocks (213) are located on the same side of the upper bracket body (211).

7. The fiber Bragg grating strain gauge according to claim 1, It is characterized in that The decompression portion (23) comprises a decompression body (231), a plurality of ribs (232) and a plurality of anti-slip sheets (233); the decompression body (231) is in the shape of a hollow prism; the decompression body (231) is fixedly arranged on the lower surface of the upper bracket body (211) and the upper surface of the lower bracket body (221).

8. The fiber Bragg grating strain gauge according to claim 7, It is characterized in that The ribs (232) are all fixedly arranged on the inner surface of the decompression body (231), and the anti-slip sheets (233) are all fixedly arranged on the inner surface of the decompression body (231) and are located between adjacent ribs (232).

9. The fiber Bragg grating strain gauge according to claim 8, It is characterized in that The anti-slip sheet (233) comprises a first anti-slip sheet (2331), a second anti-slip sheet (2332) and a plurality of notches (2333).

10. The fiber Bragg grating strain gauge according to claim 9, It is characterized in that The first anti-slip sheet (2331) is fixedly arranged on the outer surface of the decompression body (231), the second anti-slip sheet (2332) is fixedly arranged on the inner surface of the decompression body (231), and the notches (2333) are both located at the front end of the second anti-slip sheet (2332) and inside the decompression body (231).

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