Fiber grating sensor composite material packaging structure

Abstract

The utility model discloses a composite material packaging structure of a fiber grating sensor, and relates to the technical field of fiber grating sensors, in particular to the composite material packaging structure of the fiber grating sensor, which comprises an armor optical cable, and a grating is carved on the exposed part of the end part of the armor optical cable; each elastic element is vertically arranged on the outer side wall of the grating, the stress strip part of each elastic element is used for sensing stress, and the stress strip part of each elastic element expands the stress contact range of the fiber grating sensor, which is similar to sensing the stress through a plurality of antennas by the grating; the stress strip part of each elastic element directly acts the stress on the grating after being stressed, the stress reduction of other parts is avoided, compared with the prior art that a cover plate and a positioning plate are adopted to clamp and fix the grating, the stress is sensed in a large range through the plurality of elastic elements, and the stress directly acts on the grating, so that the sensitivity of the grating is greatly improved, and the reliability of the grating is improved. The measurement precision of the grating is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of optical fiber grating sensors, in particular to a composite material packaging structure of an optical fiber grating sensor. Background Art

[0002] Grating strain detection is a new type of mechanical detection method. It is pasted on the surface of the product to be tested. When the product has defects or damage, the strain after being stressed will change. By detecting the change in strain, the product can be tested. Grating strain detection has the advantages of anti-electromagnetic interference, anti-corrosion, and non-conductivity. When testing composite materials, fiber grating sensors packaged with composite materials are the best choice. Therefore, the present application provides a fiber grating sensor composite material packaging structure to meet the use requirements.

[0003] In the published Chinese patent application, the publication number is CN218211211U, and the patent name is: a composite packaging structure of a fiber grating sensor, including a cover plate, a positioning plate and a substrate, the positioning plate is fixedly arranged on the substrate, and a transverse semicircular positioning groove is arranged on the upper surface of the positioning plate, the fiber grating is placed in the positioning groove and fixed by positioning glue, and the two ends of the fiber grating are respectively passed through a protective tube and connected to a joint, and the gap between the fiber grating and the protective tube is sealed with sealant; the cover plate covers the exposed parts of the positioning plate and the fiber grating and is connected to the substrate; after the sensor is processed, the substrate is bonded to the surface of the detected object, and the cover plate, the positioning plate and the substrate are made of fiber reinforced plastic. Although it has accurate positioning, stable quality and high measurement accuracy, it can meet the user's use needs. However, the prior art uses a cover plate and a positioning plate to encapsulate the grating, and the cover plate and the positioning plate clamp the two sides of the grating, and the cover plate and the positioning plate are fixed together by positioning glue. After the grating is packaged and fixed with a cover plate and a positioning plate, the thickness of the grating protective layer is increased, which in turn increases the thickness of the grating when it is subjected to stress, weakens the direct contact between the grating and the stress, reduces the accuracy of the grating's perception of stress, and causes a decrease in the measurement accuracy of the fiber Bragg grating.

[0004] In summary, in order to solve the problem of low fiber Bragg grating measurement accuracy in the prior art, this invention is proposed to solve the problem. Utility Model Content

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the utility model provides a fiber grating sensor composite material packaging structure, which solves the problems raised in the above background technology.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the utility model is implemented through the following technical solutions: a fiber grating sensor composite material packaging structure, including an armored optical cable, a grating is engraved on the exposed end portion of the armored optical cable; and also includes a shell and a plurality of elastic elements, the armored optical cable passes through the shell, and the armored optical cable is fixedly installed with the shell, and the grating is located inside the shell;

[0009] The gratings are fixedly connected to the middle of each elastic element, and each elastic element is perpendicular to the gratings; both ends of the elastic element are fixedly connected to glass fiber filaments, and one end of the glass fiber filament away from the elastic element is fixedly connected to the inner wall of the shell;

[0010] The elastic element is composed of a stress bar portion and a hoop portion, the hoop portion is hooped on the outer side wall of the grating, and the hoop portion is fixedly connected to the grating.

[0011] Optionally, a protective layer is provided on the outer side wall of the grating, and the hoop portion of the elastic element is hooped on the outer side wall of the protective layer.

[0012] Optionally, a fixing cylinder is disposed inside the shell, the fixing cylinder covers the hoop portion of each elastic element, and the fixing cylinder is fixedly connected to the hoop portion of each elastic element, and the fixing cylinder separates each elastic element at a certain interval.

[0013] Optionally, a filling cavity is formed between the interior of the fixing tube and the protective layer, and the filling cavity is filled with a filler.

[0014] Optionally, a heat insulation layer is fixedly connected to the inner wall of the shell, and the heat insulation layer is made of ceramic silicone rubber material.

[0015] Optionally, it also includes a substrate, the four edges of the substrate are fixedly connected to the inner wall of the shell, a plurality of support blocks are fixedly connected to a side wall of the substrate close to the grating, and one end of the glass fiber yarn away from the elastic element is fixedly connected to the support block.

[0016] Optionally, the substrate is made of glass fiber material.

[0017] (III) Beneficial effects

[0018] The utility model provides a fiber grating sensor composite material packaging structure, which has the following beneficial effects:

[0019] 1. The fiber Bragg grating sensor composite material packaging structure has the effect of improving the measurement accuracy of the fiber Bragg grating sensor through the coordinated arrangement of the grating and the elastic element. Each elastic element is vertically arranged on the outer wall of the grating. The stress bar portion of each elastic element is used to sense the stress. The stress bar portion of each elastic element expands the stress contact range of the fiber Bragg grating sensor, similar to the grating sensing stress through multiple tentacles. After being stressed, the stress bar portion of each elastic element directly acts on the grating to avoid other components from reducing the stress. Compared with the prior art that uses a cover plate and a positioning plate to clamp and fix the grating, the stress is sensed over a large range through multiple elastic elements and the stress is directly applied to the grating, which greatly improves the sensitivity of the grating and improves the measurement accuracy of the grating.

[0020] 2. Glass fiber filaments are arranged at both ends of the elastic element, and the stress is sensed by using the end of the glass fiber filament far away from the sensing element. The glass fiber filament is more flexible than the elastic element. The end of the glass fiber filament applies force to the elastic element after being stressed, and the elastic element applies stress to the grating. While expanding the stress sensing range, the glass fiber filament also improves the sensitivity of remote stress sensing, making stress transmission more accurate and reducing stress loss during the transmission process, thereby greatly improving the sensitivity of the grating and improving the measurement accuracy of the grating. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0022] Figure 1 This is a three-dimensional structural schematic diagram of a fiber grating sensor composite material packaging structure of the utility model;

[0023] Figure 2 This is a schematic cross-sectional view of a composite material packaging structure of a fiber grating sensor according to the utility model;

[0024] Figure 3 It is a three-dimensional structural schematic diagram of a fixing tube in a composite material packaging structure of a fiber grating sensor of the utility model;

[0025] Figure 4 It is a partial cross-sectional structural schematic diagram of a fixing tube in a composite material packaging structure of a fiber grating sensor of the utility model;

[0026] Figure 5This is a schematic diagram of the three-dimensional structure of a protective layer in a composite material packaging structure of a fiber grating sensor of the utility model;

[0027] Figure 6 The utility model is a three-dimensional structural schematic diagram of a sensing element in a composite material packaging structure of a fiber grating sensor.

[0028] In the figure: 1, shell; 2, armored optical cable; 3, grating; 4, thermal insulation layer; 5, protective layer; 6, elastic element; 601, stress bar part; 602, hoop part; 7, fixing tube; 8, filling cavity; 9, glass fiber filament; 10, support block; 11, substrate. DETAILED DESCRIPTION

[0029] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indications or implications.

[0030] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments.

[0031] For example, see Figures 1 to 6 The utility model provides a technical solution: a fiber grating sensor composite material packaging structure, including an armored optical cable 2, and a grating 3 is engraved on the exposed end portion of the armored optical cable 2. A fiber grating sensor composite material packaging structure also includes a shell 1 and a plurality of elastic elements 6. The armored optical cable 2 penetrates the shell 1, and the armored optical cable 2 is fixedly installed with the shell 1, and the grating 3 is located inside the shell 1.

[0032] The housing 1 is used to provide the outermost protection for the grating 3 .

[0033] The grating 3 is fixedly connected to the middle of each elastic element 6, and each elastic element 6 is perpendicular to the grating 3. Glass fiber filaments 9 are fixedly connected to both ends of the elastic element 6, and one end of the glass fiber filament 9 away from the elastic element 6 is fixedly connected to the inner side wall of the housing 1. The elastic element 6 is composed of a stress bar portion 601 and a hoop portion 602, and the hoop portion 602 is hooped on the outer side wall of the grating 3, and the hoop portion 602 is fixedly connected to the grating 3.

[0034] Among them, each elastic element 6 is used to sense stress. The elastic element 6 can be made of metal foil, and the elastic element 6 has a certain elasticity. Each elastic element 6 is vertically arranged on the outer wall of the grating 3, and the stress bar portion 601 of each elastic element 6 is used to sense stress. The stress bar portion 601 of each elastic element 6 expands the stress contact range of the fiber grating sensor, just like the grating 3 senses stress through multiple tentacles. After being stressed, the stress bar portion 601 of each elastic element 6 directly applies stress to the grating 3, avoiding other components from reducing stress. By sensing stress over a large range through multiple elastic elements 6, and directly applying stress to the grating 3, the sensitivity of the grating 3 is greatly improved, and the measurement accuracy of the grating 3 is improved. The glass fiber filament 9 is used to expand the stress sensing range, and at the same time, it is used to improve the sensitivity of the elastic element 6 to sense stress at the far end. The stress is sensed by using the end of the glass fiber 9 away from the sensing element 6. The glass fiber 9 is more resilient than the elastic element 6. The end of the glass fiber 9 applies force to the elastic element 6 after being stressed, and the elastic element 6 applies stress to the grating 3. While expanding the stress sensing range, the glass fiber 9 also improves the sensitivity of far-end stress sensing, makes the stress transmission more accurate, and reduces the stress loss during the transmission process, thereby greatly improving the sensitivity of the grating 3 and improving the measurement accuracy of the grating 3.

[0035] Specifically, a protective layer 5 is provided on the outer side wall of the grating 3 , and the hoop portion 602 of the elastic element 6 is hooped on the outer side wall of the protective layer 5 .

[0036] The protective layer 5 can be made of resin, and the wall thickness of the protective layer 5 is relatively thin. The protective layer 5 is only used to prevent the elastic element 6 from directly contacting the grating 3 to avoid damage to the grating 3.

[0037] More specifically, a fixing tube 7 is disposed inside the shell 1 , which covers the hoop portion 602 of each elastic element 6 , and is fixedly connected to the hoop portion 602 of each elastic element 6 , so that the fixing tube 7 separates each elastic element 6 by a certain distance.

[0038] The elastic element 6 is made into a long strip shape instead of a plate shape in order to prevent the stress from being diffused over a large area during the conduction, thereby reducing the stress. The fixed tube 7 is used to separate the elastic elements by a certain distance. Although the fixed tube 7 is fixedly connected to the hoop portion 602 of each elastic element 6, since the fixed tube 7 is close to the grating 3, when the stress on the elastic element 6 is transmitted to the fixed tube 7, it will also be transmitted to the grating 3, and the strength of the fixed tube 7 to reduce the stress is relatively small.

[0039] More specifically, a filling cavity 8 is formed between the interior of the fixing tube 7 and the protective layer 5 , and the filling cavity 8 is filled with a filler.

[0040] The filling material in the filling cavity 8 may be a rare gas, and the filling cavity 8 may also be in a vacuum state.

[0041] Specifically, a heat insulating layer 4 is fixedly connected to the inner wall of the shell 1 , and the heat insulating layer 4 is made of ceramic silicone rubber material.

[0042] The heat insulation layer 4 is used to prevent the invasion of external heat and avoid the heat from affecting the grating 3.

[0043] For example 2, please refer to Figures 1 to 6 The main difference between this embodiment and the first embodiment is that: a fiber grating sensor composite material packaging structure further includes a substrate 11, the four edges of the substrate 11 are fixedly connected to the inner side wall of the housing 1, a plurality of support blocks 10 are fixedly connected to a side wall of the substrate 11 close to the grating 3, and one end of the glass fiber filament 9 away from the elastic element 6 is fixedly connected to the support block 10. The substrate 11 is made of glass fiber material.

[0044] The substrate 11 is fixedly mounted on the bottom of the housing 1, and is used as the bottom plate of the housing 1. The substrate 11 can effectively protect the elastic element 6 and the like, and prevent the invasion of external impurities and dust. At the same time, the substrate 11 is also used to directly contact the object to be measured. After sensing the stress, the substrate 11 applies the stress to the elastic element 6 or the glass fiber filament 9, and the elastic element 6 or the glass fiber filament 9 applies the stress to the grating 3.

[0045] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A fiber grating sensor composite material packaging structure, comprising an armored optical cable (2), wherein a grating (3) is engraved on the exposed end portion of the armored optical cable (2); characterized in that: It also comprises a housing (1) and a plurality of elastic elements (6), the armored optical cable (2) passes through the housing (1), and the armored optical cable (2) and the housing (1) are fixedly mounted, and the grating (3) is located inside the housing (1); The grating (3) is fixedly connected to the middle of each elastic element (6), and each elastic element (6) is perpendicular to the grating (3); both ends of the elastic element (6) are fixedly connected to glass fiber yarns (9), and one end of the glass fiber yarn (9) away from the elastic element (6) is fixedly connected to the inner wall of the housing (1); The elastic element (6) is composed of a stress bar portion (601) and a hoop portion (602); the hoop portion (602) is hooped on the outer side wall of the grating (3); and the hoop portion (602) is fixedly connected to the grating (3).

2. The fiber grating sensor composite material packaging structure according to claim 1, characterized in that: A protective layer (5) is provided on the outer side wall of the grating (3), and the hoop portion (602) of the elastic element (6) is hooped on the outer side wall of the protective layer (5).

3. The fiber grating sensor composite material packaging structure according to claim 2, characterized in that: A fixing tube (7) is arranged inside the shell (1), the fixing tube (7) covers the hoop portion (602) of each elastic element (6), and the fixing tube (7) is fixedly connected to the hoop portion (602) of each elastic element (6), and the fixing tube (7) separates each elastic element (6) at a certain distance.

4. The fiber grating sensor composite material packaging structure according to claim 3, characterized in that: A filling cavity (8) is formed between the interior of the fixing cylinder (7) and the protective layer (5), and the filling cavity (8) is filled with a filler.

5. The fiber grating sensor composite material packaging structure according to claim 1, characterized in that: A heat insulation layer (4) is fixedly connected to the inner side wall of the shell (1), and the heat insulation layer (4) is made of ceramic silicone rubber material.

6. The fiber grating sensor composite material packaging structure according to claim 1, characterized in that: It also comprises a base plate (11), the four edges of the base plate (11) being fixedly connected to the inner wall of the shell (1), a plurality of support blocks (10) being fixedly connected to a side wall of the base plate (11) close to the grating (3), and one end of the glass fiber filament (9) away from the elastic element (6) being fixedly connected to the support block (10).

7. The fiber grating sensor composite material packaging structure according to claim 6, characterized in that: The base plate (11) is made of glass fiber material.

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