Novel fiber grating strain sensor

Abstract

The utility model discloses a novel fiber bragg grating strain sensor, which belongs to the technical field of fiber bragg grating sensors and comprises two substrates, a substrate guide rail is connected between the two substrates, and bollards are connected above the two substrates. According to the utility model, the lap joint assembly is arranged, redundant leading-out section optical fibers are folded and placed on the lap joint plate, the pushing plate moves under the extrusion action of the optical fibers, the pushing plate moves to drive the moving block to move in the moving groove, the moving block moves to extrude the compression spring, and then the fixed screw rod is rotated to rotate along the threaded hole; the fixing screw rotates and moves to drive the pressing disc to rotate and move, after the pressing disc moves to be attached to the side wall of the pushing plate, rotation of the fixing screw is stopped, redundant optical fibers can be lapped and fixed through the pushing plate and the lapping plate, friction between the optical fibers and objects in the surrounding environment is avoided, abrasion of the optical fibers can be avoided, and the service life of the optical fibers is prolonged. The use effect of the fiber is ensured.

Description

Technical Field

[0001] This utility model belongs to the field of fiber optic grating sensor technology, and specifically relates to a novel fiber optic grating strain sensor. Background Technology

[0002] Fiber Bragg grating (FBG) sensors are a type of fiber optic sensor. The sensing process based on FBGs obtains sensing information by modulating the Bragg wavelength of the fiber optic cable with external physical parameters. It is a wavelength modulation type fiber optic sensor.

[0003] Chinese Patent Application No. 202210407890.2 discloses a glue-free fiber Bragg grating strain sensor, relating to the field of fiber Bragg grating sensor technology. The sensor includes a substrate, substrate guide rails, tethering posts, optical fibers, fastening slots, and a helical pitch adjustment device. Tethering posts for encapsulating both ends of the optical fiber are fixed to the upper part of the substrate, and the two substrates are connected by the substrate guide rails, allowing them to slide relative to each other along the guide rail direction. The optical fiber with a Bragg grating is wound around the tethering posts from top to bottom on both sides, with the lower end of the fiber secured by the fastening slots. The friction between the fiber wound with a sufficient number of turns on the tethering posts and the tethering posts effectively fixes the fiber, and the fiber can be pre-stressed by fine-tuning the substrate spacing to prevent fiber slack. The sensor of this invention uses glue-free encapsulation, resulting in a long service life, high durability, and higher accuracy and stability under long-term use. It eliminates the need for fiber welding, simplifying the installation process, reducing costs, and facilitating mass production.

[0004] The aforementioned patent utilizes an extended optical fiber to connect to an external demodulator. However, when the extended optical fiber is long, it is prone to friction with objects in the external environment, causing wear and tear and affecting its performance. Additionally, the optical fiber is wound around a mooring post, but during the winding process, the optical fiber can easily detach from the mooring post through the top, affecting the secure connection of the optical fiber. Utility Model Content

[0005] To address the problems mentioned in the background section, this invention provides a novel fiber optic strain sensor with features of overlapping fixation and limiting to prevent detachment.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a novel fiber optic strain sensor, comprising a substrate, wherein two substrates are provided, a substrate guide rail is connected between the two substrates, a mooring post is connected above each of the two substrates, an optical fiber is sleeved around the periphery of the two mooring posts, a fixing mechanism is provided between the substrate and the optical fiber, an overlapping component is provided on the side of the two substrates that are far apart from each other, and an anti-detachment component is provided above the mooring post.

[0007] Preferably, the overlapping assembly includes a clamping member, a U-shaped frame, a push plate, an overlapping plate, a moving block, a moving groove, and a compression spring. The two bases are connected to overlapping plates on opposite sides. A U-shaped frame is connected above the overlapping plate. A push plate is provided inside the U-shaped frame. Moving blocks are connected to both ends of the push plate. A moving groove is provided on the inner sidewall of the U-shaped frame at the position corresponding to the moving block. A compression spring is connected between the moving block and the moving groove. A clamping member is provided between the U-shaped frame and the push plate.

[0008] Preferably, the clamping component includes a fixing screw, a threaded hole, and a clamping plate. The U-shaped frame is provided with a threaded hole, and the fixing screw is connected inside the threaded hole. The clamping plate is connected to one end of the fixing screw near the push plate.

[0009] Preferably, the anti-detachment component includes a limiting end ring, a fixed threaded cylinder, an annular cavity, a clamping ring, a rubber ring, a rotating screw, and abutment members. The limiting end ring is connected above the mooring bollard. The limiting end ring has an annular cavity inside. The fixed threaded cylinder is connected to both ends of the annular cavity. The rotating screw is connected to the inside of the fixed threaded cylinder. Abutment members are provided on both sides of the annular cavity. A clamping ring is provided below the rotating screw. A rubber ring is connected to the side of the clamping ring away from the rotating screw.

[0010] Preferably, the abutting member includes a return spring, a receiving cavity, and an abutting block. The inner sidewall of the annular cavity is provided with receiving cavities at both ends, and the abutting block is inserted into the receiving cavity. A return spring is connected between the receiving cavity and the abutting block.

[0011] Preferably, a push rod is connected to one end of the abutment block near the receiving cavity, and a push groove is provided on the side wall of the receiving cavity at the position corresponding to the push rod.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] 1. This utility model features a splicing assembly. Excess fiber optic leads are folded and placed onto a splicing plate. The push plate moves under the pressure of the fiber optics, causing a moving block to move inside the moving groove. The moving block compresses a spring, and the fixing screw is rotated to rotate along the threaded hole. The rotation of the fixing screw causes the pressure plate to rotate. When the pressure plate moves and adheres to the side wall of the push plate, the rotation of the fixing screw stops. The push plate and splicing plate can be used to splice and fix excess fiber optics, preventing friction between the fiber optics and objects in the surrounding environment, thus preventing fiber optic wear and ensuring the effectiveness of the fiber optics.

[0014] 2. This utility model is equipped with an anti-detachment component. After the optical fiber is wound and sleeved onto the mooring bollard, the abutment block moves into the receiving cavity. The movement of the abutment block compresses the reset spring, and the clamping ring loses the abutment effect of the abutment block. Under the action of gravity, it moves down and detaches from the annular cavity. When the clamping ring moves and adheres to the side wall of the optical fiber, the clamping ring is blocked and stops moving. Then, the rotating screw is rotated to move along the fixed threaded cylinder. When the rotating screw moves and adheres to the side wall of the clamping ring, the rotation of the rotating screw is stopped. The rotating screw can be used to limit and fix the clamping ring, and the clamping ring can be used to press and fix the optical fiber, preventing the optical fiber from detaching from the mooring bollard and ensuring the stability of the optical fiber winding and sleeve. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 This is a cross-sectional view of the present invention;

[0017] Figure 3 This utility model Figure 2 Enlarged view of point A in the middle;

[0018] Figure 4 This is a cross-sectional view of the connection state between the overlapping plate and the U-shaped frame of this utility model.

[0019] Figure 5 This is a cross-sectional view of the limiting end ring of this utility model;

[0020] Figure 6 This utility model Figure 5 Enlarged view of point B in the middle.

[0021] In the diagram: 1. Base; 2. Base guide rail; 3. Fixing mechanism; 4. Optical fiber; 5. Anti-detachment component; 51. Limiting end ring; 52. Fixing threaded cylinder; 53. Annular cavity; 54. Pressure ring; 55. Rubber ring; 56. Rotating screw; 57. Abutment component; 571. Return spring; 572. Receiving cavity; 573. Abutment block; 6. Mooring post; 7. Overlap component; 71. Pressure component; 711. Fixing screw; 712. Threaded hole; 713. Pressure plate; 72. U-shaped frame; 73. Push plate; 74. Overlap plate; 75. Moving block; 76. Moving groove; 77. Compression spring. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example 1

[0023] Please see Figure 1-6 The present invention provides the following technical solution: a novel fiber optic strain sensor, comprising a base 1, wherein two bases 1 are provided, a base guide rail 2 is connected between the two bases 1, a mooring post 6 is connected above each of the two bases 1, an optical fiber 4 is sleeved around the periphery of the two mooring posts 6, a fixing mechanism 3 is provided between the base 1 and the optical fiber 4, an overlapping component 7 is provided on the side of the two bases 1 that is far apart from each other, and an anti-detachment component 5 is provided above the mooring post 6.

[0024] Specifically, the overlapping assembly 7 includes a clamping member 71, a U-shaped frame 72, a pushing plate 73, an overlapping plate 74, a moving block 75, a moving groove 76, and a compression spring 77. The overlapping plates 74 are connected to the sides of the two bases 1 that are far apart from each other. A U-shaped frame 72 is connected above the overlapping plate 74. A pushing plate 73 is disposed inside the U-shaped frame 72. Moving blocks 75 are connected to both ends of the pushing plate 73. A moving groove 76 is disposed on the inner sidewall of the U-shaped frame 72 at the position corresponding to the moving block 75. A compression spring 77 connects the moving block 75 and the moving groove 76. A clamping member 71 is disposed between the U-shaped frame 72 and the pushing plate 73.

[0025] By adopting the above technical solution, after connecting the outgoing optical fiber 4 to an external demodulator, the excess optical fiber 4 is folded and placed on the splicing plate 74. The push plate 73 moves under the pressure of the optical fiber 4. The movement of the push plate 73 drives the moving block 75 to move inside the moving groove 76. The moving block 75 moves to compress the compression spring 77. Then, the pressing member 71 is used to press the push plate 73. The push plate 73 and the splicing plate 74 can be used to splice and fix the excess optical fiber 4, avoiding friction between the optical fiber 4 and objects in the surrounding environment, thereby preventing wear of the optical fiber 4 and ensuring the performance of the optical fiber 4.

[0026] Specifically, the clamping component 71 includes a fixing screw 711, a threaded hole 712, and a clamping plate 713. The U-shaped frame 72 is provided with a threaded hole 712, and the fixing screw 711 is connected inside the threaded hole 712. The end of the fixing screw 711 near the push plate 73 is connected to the clamping plate 713.

[0027] By adopting the above technical solution, the fixing screw 711 is rotated and moved along the threaded hole 712. The rotation and movement of the fixing screw 711 drives the pressure plate 713 to rotate and move. When the pressure plate 713 moves and fits against the side wall of the push plate 73, the rotation of the fixing screw 711 is stopped. The pressure plate 713 can be used to press and fix the push plate 73, ensuring the stability of the push plate 73.

[0028] In this embodiment, the optical fiber 4 is wound and sleeved onto two mooring bollards 6, and the two ends of the optical fiber 4 are fixed using the fixing mechanism 3. Then, the distance between the two bases 1 is adjusted using the base guide rail 2, thereby enabling the pre-tension adjustment of the fiber grating of this invention. The base 1 is then installed onto the fiber grating strain gauge structure using external fixing bolts. The optical fiber 4 led out from the fixing mechanism 3 is then connected to an external demodulator, and the excess lead-out section of optical fiber 4 is folded and placed on the splice plate 74. The push plate 73 moves under the pressure of the optical fiber 4, and the movement of the push plate 73 drives the moving block 75 in the moving groove 76. The internal movement of the moving block 75 compresses the spring 77, and then the fixed screw 711 is rotated to rotate along the threaded hole 712. The rotation of the fixed screw 711 drives the pressure plate 713 to rotate. When the pressure plate 713 moves and fits against the side wall of the push plate 73, the rotation of the fixed screw 711 stops. The push plate 73 and the overlapping plate 74 can be used to overlap and fix the excess optical fiber 4, so as to avoid friction between the optical fiber 4 and objects in the surrounding environment, thereby avoiding wear of the optical fiber 4 and ensuring the performance of the optical fiber 4. The demodulator measures and collects the data transmitted by the fiber optic grating to realize the measurement of the structural strain. Example 2

[0029] The difference between this embodiment and Embodiment 1 is that the anti-detachment component 5 includes a limiting end ring 51, a fixed threaded cylinder 52, an annular cavity 53, a clamping ring 54, a rubber ring 55, a rotating screw 56, and an abutment member 57. The limiting end ring 51 is connected above the mooring bollard 6. The limiting end ring 51 has an annular cavity 53 inside. The fixed threaded cylinder 52 is connected to both ends of the annular cavity 53. The rotating screw 56 is connected inside the fixed threaded cylinder 52. Abutment members 57 are provided on both sides of the annular cavity 53. The clamping ring 54 is provided below the rotating screw 56. The rubber ring 55 is connected to the side of the clamping ring 54 away from the rotating screw 56.

[0030] Specifically, the abutment member 57 includes a return spring 571, a receiving cavity 572, and an abutment block 573. Receiving cavities 572 are provided at both ends of the inner wall of the annular cavity 53. An abutment block 573 is inserted into the inside of each receiving cavity 572. A return spring 571 connects the receiving cavity 572 and the abutment block 573.

[0031] By adopting the above technical solution, the abutment block 573 moves into the cavity 572, the abutment block 573 moves to compress the return spring 571, and then the clamping ring 54 moves into the annular cavity 53. Then the abutment block 573 is released, the return spring 571 loses the external force and returns to its original shape, driving the abutment block 573 to move out of the cavity 572. The abutment block 573 can be used to abut and fix the clamping ring 54, ensuring the stability of the clamping ring 54 and avoiding the clamping ring 54 from affecting the winding and splicing effect of the optical fiber 4 and the mooring post 6.

[0032] Specifically, a push rod is connected to one end of the abutment block 573 near the receiving cavity 572, and a push groove is provided on the side wall of the receiving cavity 572 at the position corresponding to the push rod.

[0033] By adopting the above technical solution, when it is necessary to move the abutment block 573, the push rod is moved along the push groove. The movement of the push rod causes the abutment block 573 to move and be retracted into the receiving cavity 572, which makes it convenient for the operator to move the abutment block 573.

[0034] In this embodiment, after the optical fiber 4 is wound and sleeved onto the mooring post 6, the abutment block 573 is moved into the receiving cavity 572. The movement of the abutment block 573 compresses the return spring 571, and the clamping ring 54 loses the abutment effect of the abutment block 573. Under the action of gravity, it moves down and disengages from the annular cavity 53. When the clamping ring 54 moves and adheres to the side wall of the optical fiber 4, the clamping ring 54 is blocked and stops moving. Then, the rotating screw 56 is rotated to rotate along the fixed threaded cylinder 52. When the rotating screw 56 moves and adheres to the side wall of the clamping ring 54, the rotation of the rotating screw 56 is stopped. The rotating screw 56 can be used to limit and fix the clamping ring 54. The clamping ring 54 can be used to press and fix the optical fiber 4, preventing the optical fiber 4 from detaching from the mooring post 6 and ensuring the stability of the winding and sleeved connection of the optical fiber 4.

[0035] The structure and principle of the fixing mechanism 3, which consists of a cover plate, a cover plate magnet, a base plate magnet, a buckle, an elastic pad, a V-groove, and a base plate, have been disclosed in a glue-free fiber optic strain sensor disclosed in Chinese patent application number 202210407890.2. Its working principle is as follows: a base plate is connected above the substrate 1, a V-groove is provided above the base plate, a cover plate is connected above the base plate, a cover plate magnet is connected to the side of the cover plate near the base plate, a base plate magnet is connected to the side wall of the base plate at the position corresponding to the cover plate magnet, and a buckle is connected to the side wall of the cover plate. In use, the end of the optical fiber 4, which is wound and sleeved on the mooring bollard 6, is placed inside the V-groove, and then the cover plate is rotated to close. The buckle is used to snap the cover plate and the base plate together. At the same time, the cover plate magnet and the base plate magnet attract and fix each other. Under the action of the cover plate and the base plate, the end of the optical fiber 4 can be fixed.

[0036] The working principle and usage process of this utility model are as follows: The optical fiber 4 is wound and sleeved onto two mooring posts 6, and the two ends of the optical fiber 4 are fixed using the fixing mechanism 3. After the optical fiber 4 is wound and sleeved onto the mooring posts 6, the abutment block 573 moves into the receiving cavity 572. The movement of the abutment block 573 compresses the return spring 571, causing the clamping ring 54 to lose its abutment effect and move downwards and away from the annular cavity 53 under gravity. When the clamping ring 54 moves and adheres to the side wall of the optical fiber 4, the pressure... When the clamping ring 54 stops moving due to obstruction, the rotating screw 56 is then rotated to move along the fixed threaded cylinder 52. Once the rotating screw 56 moves and comes into contact with the side wall of the clamping ring 54, rotation of the rotating screw 56 stops. The rotating screw 56 can be used to limit and fix the clamping ring 54, and the clamping ring 54 can be used to press and fix the optical fiber 4, preventing the optical fiber 4 from detaching from the mooring post 6 and ensuring the stability of the winding and splicing of the optical fiber 4. Then, the distance between the two bases 1 can be adjusted using the base guide rail 2, thereby realizing the functionality of the present invention. The fiber grating is pre-stressed, and then the base 1 is installed on the fiber grating strain gauge structure with the help of external fixing bolts. Then, the fiber 4 led out from the fixing mechanism 3 is connected to the external demodulator, and the excess fiber 4 is folded and placed on the splicing plate 74. The push plate 73 moves under the pressure of the fiber 4. The movement of the push plate 73 drives the moving block 75 to move inside the moving groove 76. The moving block 75 moves and compresses the compression spring 77. Then, the fixing screw 711 is rotated to rotate along the threaded hole 712. The rotation of the fixing screw 711 drives the pressure plate 713 to rotate. When the pressure plate 713 moves and fits against the side wall of the push plate 73, the rotation of the fixing screw 711 is stopped. The push plate 73 and the splicing plate 74 can be used to splice and fix the excess fiber 4 to avoid friction between the fiber 4 and objects in the surrounding environment, thereby avoiding wear of the fiber 4 and ensuring the performance of the fiber 4. The demodulator measures and collects the data transmitted by the fiber grating to realize the measurement of the structural strain.

[0037] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A novel fiber optic strain sensor, comprising a substrate (1), wherein two substrates (1) are provided, a substrate guide rail (2) is connected between the two substrates (1), a mooring post (6) is connected above each of the two substrates (1), an optical fiber (4) is sleeved around the periphery of the two mooring posts (6), and a fixing mechanism (3) is provided between the substrate (1) and the optical fiber (4), characterized in that: Both bases (1) are provided with overlapping components (7) on the side away from each other, and anti-detachment components (5) are provided above the mooring piles (6).

2. The novel fiber optic strain sensor according to claim 1, characterized in that: The overlapping assembly (7) includes a clamping member (71), a U-shaped frame (72), a push plate (73), an overlapping plate (74), a moving block (75), a moving groove (76), and a compression spring (77). The two bases (1) are connected to overlapping plates (74) on opposite sides. A U-shaped frame (72) is connected above the overlapping plate (74). A push plate (73) is provided inside the U-shaped frame (72). Moving blocks (75) are connected to both ends of the push plate (73). A moving groove (76) is provided on the inner sidewall of the U-shaped frame (72) at the position corresponding to the moving block (75). A compression spring (77) is connected between the moving block (75) and the moving groove (76). A clamping member (71) is provided between the U-shaped frame (72) and the push plate (73).

3. The novel fiber optic strain sensor according to claim 2, characterized in that: The clamping component (71) includes a fixing screw (711), a threaded hole (712) and a clamping plate (713). The U-shaped frame (72) is provided with a threaded hole (712), and the fixing screw (711) is connected inside the threaded hole (712). The clamping plate (713) is connected to one end of the fixing screw (711) near the push plate (73).

4. The novel fiber optic strain sensor according to claim 1, characterized in that: The anti-detachment component (5) includes a limiting end ring (51), a fixed threaded cylinder (52), an annular cavity (53), a clamping ring (54), a rubber ring (55), a rotating screw (56), and an abutment (57). The limiting end ring (51) is connected above the mooring bollard (6). An annular cavity (53) is provided inside the limiting end ring (51). The fixed threaded cylinder (52) is connected to both ends of the annular cavity (53). The rotating screw (56) is connected inside the fixed threaded cylinder (52). An abutment (57) is provided on both sides of the annular cavity (53). A clamping ring (54) is provided below the rotating screw (56). A rubber ring (55) is connected to the side of the clamping ring (54) away from the rotating screw (56).

5. A novel fiber optic strain sensor according to claim 4, characterized in that: The abutting member (57) includes a return spring (571), a receiving cavity (572) and an abutting block (573). The inner sidewall of the annular cavity (53) is provided with a receiving cavity (572) at both ends. The abutting block (573) is inserted into the receiving cavity (572). The return spring (571) is connected between the receiving cavity (572) and the abutting block (573).

6. A novel fiber optic strain sensor according to claim 5, characterized in that: The abutment block (573) is connected to a push rod at one end near the receiving cavity (572), and a push groove is provided on the side wall of the receiving cavity (572) at the position corresponding to the push rod.

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