Fiber grating acceleration sensor

Abstract

The utility model discloses a fiber bragg grating acceleration sensor, which belongs to the technical field of optical fiber sensing and comprises a lower shell, a bonding layer is bonded on the lower end face of the lower shell, an upper shell is clamped on the upper end face of the lower shell, and a mass block body is slidably connected in a shell structure formed by the lower shell and the upper shell. According to the utility model, the mass block sliding mechanism is arranged, so that the mass block can slide more smoothly, the problem that the friction force between the mass block and the shell during sliding is relatively large is avoided, and the acceleration detection work in the object moving process is influenced by the friction force factor; compared with the prior art, the shell fixing mechanism is arranged, the upper shell and the lower shell can be conveniently installed and fixed through the shell fixing mechanism, compared with an existing buckle structure, the fixing structure is relatively convenient to disassemble and assemble, the buckle structure is relatively well protected, and the overall service life is longer.

Description

Technical Field

[0001] This utility model belongs to the field of fiber optic sensing technology, specifically relating to a fiber optic grating accelerometer. Background Technology

[0002] In recent years, with the rapid development of fiber optic communication and fiber optic sensing technologies, research on fiber Bragg grating-based accelerometers has received increasing attention from experts and scholars. Researchers have continuously improved the performance of fiber Bragg grating accelerometers by optimizing the sensor's structural design and enhancing the accuracy of demodulation techniques.

[0003] Chinese patent application number 201621449599.8 discloses a compact fiber Bragg grating accelerometer sensor, comprising a rectangular housing, a first elastic element connected at one end to the housing and at the other end to a mass block, the first elastic element and the mass block being capable of vibrating along the axial direction of the housing; the first elastic element contains a first fixed block, a second fixed block, and a second elastic element located between the first fixed block and the second fixed block; one end of the fiber Bragg grating is bonded to the housing, passing sequentially through the second fixed block, the second elastic element, the first fixed block, and the mass block, and the other end is bonded to the mass block. This compact fiber Bragg grating accelerometer sensor, as described in this invention, forms an integral fiber Bragg grating spring oscillator structure, featuring a compact structure, small size, good consistency, and high measurement accuracy; furthermore, two aligned fixed blocks are provided around the fiber Bragg grating, further improving the sensor's measurement accuracy.

[0004] While the aforementioned patents have enabled the use of fiber optic accelerometers, in actual use, when an object moves, although the mass block slides inside the housing due to inertia, the large contact area between the mass block and the housing results in relatively high friction, which may affect the accuracy of the monitored data. Furthermore, sensor housings are mostly secured by internal clips; however, this method requires tools to pry them open during disassembly, and if the clips are not located, they can easily be damaged, affecting the reliability of secondary fixation. Utility Model Content

[0005] To address the problems mentioned in the background section, this invention provides a fiber optic grating accelerometer sensor, which features better sliding performance of the mass block inside the housing and convenient assembly and disassembly between housings.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a fiber optic grating accelerometer, comprising a lower housing, an adhesive layer attached to the lower end face of the lower housing, an upper housing snapped onto the upper end face of the lower housing, a mass block body slidably connected inside the housing structure formed by the lower housing and the upper housing, a second fixing block connected to one side of the mass block body by screws, a second elastic element connected to the other end of the second fixing block by screws, a first fixing block connected to the other end of the second elastic element by screws, a first elastic element sleeved on the outer surface of the second elastic element, the second fixing block and the first fixing block, a fiber optic grating inserted inside the mass block body, the second elastic element, the second fixing block and the first fixing block and extending outward from the outer side of the housing structure formed by the lower housing and the upper housing, a mass block body slidably connected to the housing structure formed by the lower housing and the upper housing by a mass block sliding mechanism, and a housing fixing mechanism fixing the lower housing and the upper housing.

[0007] Preferably, the mass block sliding mechanism includes a first slide rail, a rotating shaft, a first pulley, a slider, and a side sliding structure. A slider is fixedly connected to the upper end of the mass block body. A first pulley is rotatably connected to the center of the slider. The two ends of the first pulley are rotatably connected to the slider through a rotating shaft. A first slide rail corresponding to the slider is installed between the bottom of the lower shell and the top wall of the upper shell. The side of the mass block body is slidably connected to the shell structure composed of the lower shell and the upper shell through the side sliding structure.

[0008] Preferably, the side sliding structure includes a groove, a second pulley, an embedding groove, and a second slide rail. The side of the mass block body is provided with a groove, and the second pulley is rotatably connected to the side of the groove by a pin and extends out of the groove. The inside of the mass block body is provided with an embedding groove corresponding to the second pulley, and the inner walls of the lower shell and the upper shell are provided with second slide rails corresponding to the grooves.

[0009] Preferably, the housing fixing mechanism includes a locking block, a fixing hole, a fixing component, and a locking slot. Two sets of locking blocks are provided at the lower diagonal of the upper housing, and a locking slot corresponding to the locking block is provided at the upper diagonal of the lower housing. A fixing component is provided inside the side of the locking slot, and a fixing hole corresponding to the fixing component is provided on the side of the locking block.

[0010] Preferably, the housing fixing mechanism further includes positioning blocks and positioning grooves. Positioning blocks are installed at the other two corners at the lower end of the upper housing, and positioning grooves corresponding to the positioning blocks are opened at the other two corners at the upper end of the lower housing.

[0011] Preferably, the fixing component includes a spring, an adjusting groove, an adjusting block, and a fixing rod. The side of the groove is located inside the lower housing and a spring is provided. The other end of the spring is provided with a fixing rod. An adjusting block is provided at the side edge of the fixing rod. An adjusting groove corresponding to the adjusting block is opened on the side of the lower housing.

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

[0013] 1. This utility model incorporates a mass block sliding mechanism, which allows the mass block to slide more smoothly, avoiding the problem of excessive friction between the mass block and the shell during sliding. Friction can affect the acceleration detection of an object's movement.

[0014] 2. This utility model has a shell fixing mechanism, which makes it easy to install and fix the upper and lower shells. Compared with the existing buckle structure, this fixing structure is easier to assemble and disassemble, and provides better protection for the buckle structure, resulting in a longer overall service life. Attached Figure Description

[0015] Figure 1 This is a perspective view of the present utility model;

[0016] Figure 2 This is a perspective view of the mass block sliding mechanism of this utility model;

[0017] Figure 3 This is a three-dimensional sectional view of the side sliding structure of this utility model;

[0018] Figure 4 This is a perspective view of the housing fixing mechanism of this utility model;

[0019] Figure 5 This is an enlarged view of the fixing component of this utility model;

[0020] In the diagram: 1. Lower housing; 2. Adhesive layer; 3. Housing fixing mechanism; 31. Locking block; 32. Fixing hole; 33. Positioning block; 34. Positioning groove; 35. Fixing component; 351. Spring; 352. Adjustment groove; 353. Adjustment block; 354. Fixing rod; 36. Locking groove; 4. Upper housing; 5. Fiber grating; 6. Mass block sliding mechanism; 61. First slide rail; 62. Rotating shaft; 63. First pulley; 64. Slider; 65. Side sliding structure; 651. Groove; 652. Second pulley; 653. Embedded groove; 654. Second slide rail; 7. Mass block body; 8. Second elastic element; 9. Second fixing block; 10. First fixing block; 11. First elastic element. Detailed Implementation

[0021] 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

[0022] Please see Figure 1-5 The present invention provides the following technical solution: a fiber optic grating accelerometer, including a lower housing 1, an adhesive layer 2 attached to the lower end face of the lower housing 1, an upper housing 4 snapped onto the upper end face of the lower housing 1, a mass block body 7 slidably connected inside the housing structure formed by the lower housing 1 and the upper housing 4, a second fixing block 9 connected to one side of the mass block body 7 by screws, a second elastic element 8 connected to the other end of the second fixing block 9 by screws, a first fixing block 10 connected to the other end of the second elastic element 8 by screws, a first elastic element 11 sleeved on the outer surface of the second elastic element 8, the second fixing block 9 and the first fixing block 10, a fiber optic grating 5 inserted inside the mass block body 7, the second elastic element 8, the second fixing block 9 and the first fixing block 10 and extending outward from the outer side of the housing structure formed by the lower housing 1 and the upper housing 4, a mass block body 7 slidably connected to the housing structure formed by the lower housing 1 and the upper housing 4 by a mass block sliding mechanism 6, and a housing fixing mechanism 3 fixing the lower housing 1 and the upper housing 4.

[0023] Specifically, the mass block sliding mechanism 6 includes a first slide rail 61, a rotating shaft 62, a first pulley 63, a slider 64, and a side sliding structure 65. A slider 64 is fixedly connected to the upper end of the mass block body 7. A first pulley 63 is rotatably connected to the center of the slider 64. The two ends of the first pulley 63 are rotatably connected to the slider 64 via the rotating shaft 62. A first slide rail 61 corresponding to the slider 64 is installed between the bottom of the lower housing 1 and the top wall of the upper housing 4. The side of the mass block body 7 is slidably connected to the housing structure formed by the lower housing 1 and the upper housing 4 via the side sliding structure 65.

[0024] By adopting the above technical solution, when the mass block body 7 slides due to inertia, the slider 64 will slide inside the first slide rail 61. At the same time, the first pulley 63 is rotatably connected inside the slider 64 through the rotating shaft 62. This can make the friction of the mass block body 7 relatively small when sliding, and the influence of factors on the sliding of the mass block body 7 relatively small, thereby improving the accuracy of object acceleration detection.

[0025] Specifically, the side sliding structure 65 includes a groove 651, a second pulley 652, an embedding groove 653, and a second slide rail 654. The mass block body 7 has a groove 651 on its side. The second pulley 652 is rotatably connected to the inside of the groove 651 via a pin and extends out of the groove 651. The mass block body 7 has an embedding groove 653 corresponding to the second pulley 652 inside. The inner walls of the lower housing 1 and the upper housing 4 are provided with second slide rails 654 corresponding to the groove 651.

[0026] By adopting the above technical solution, when the mass block body 7 slides, the second slide rail 654 will be slidably connected to the groove 651. At the same time, due to the setting of the second pulley 652 inside the groove 651 which is rotatably connected by a pin, the sliding effect of the mass block body 7 can be further improved.

[0027] In this embodiment, during use, the adhesive layer 2 at the lower end of the lower housing 1 is adhered to the object to be tested. When the object moves, due to inertia, the mass block body 7 will slide forward. The forward sliding of the mass block body 7 will cause the first fixed block 10 and the second fixed block 9 to move closer to each other, and cause the first elastic element 11 and the second elastic element 8 to be compressed. The corresponding fiber optic grating 5 is stretched (or compressed), and the wavelength of the fiber optic grating 5 changes. The wavelength change of the fiber optic grating 5 is monitored in real time by the high-speed wavelength demodulation center to determine the magnitude of the acceleration of the object being tested. When the mass block body 7 moves due to inertia... When sliding, the slider 64 slides inside the first slide rail 61. At the same time, the first pulley 63 is rotatably connected inside the slider 64 through the pivot 62. This makes the friction of the mass block 7 relatively small when sliding, and the influence of factors on the sliding of the mass block 7 is relatively small, thereby improving the accuracy of object acceleration detection. When the mass block 7 slides, the second slide rail 654 slides in correspondence with the groove 651. At the same time, the setting of the second pulley 652 rotatably connected inside the groove 651 through the pin can further improve the sliding effect of the mass block 7. Example 2

[0028] The difference between this embodiment and Embodiment 1 is that the housing fixing mechanism 3 includes a locking block 31, a fixing hole 32, a fixing component 35, and a locking groove 36. Two sets of locking blocks 31 are provided at the lower diagonal of the upper housing 4, and a locking groove 36 corresponding to the locking block 31 is provided at the upper diagonal of the lower housing 1. The fixing component 35 is provided inside the side of the locking groove 36, and the fixing hole 32 corresponding to the fixing component 35 is provided on the side of the locking block 31.

[0029] By adopting the above technical solution, when it is necessary to connect and fix the upper housing 4 and the lower housing 1, the locking block 31 at the lower end of the upper housing 4 is inserted into the locking groove 36 inside the lower housing 1, and then the fixing component 35 and the fixing hole 32 are used to fix the upper housing 4 and the lower housing 1.

[0030] Specifically, the housing fixing mechanism 3 also includes positioning blocks 33 and positioning grooves 34. Positioning blocks 33 are installed at the other two corners at the lower end of the upper housing 4, and positioning grooves 34 corresponding to the positioning blocks 33 are opened at the other two corners at the upper end of the lower housing 1.

[0031] By adopting the above technical solution, when the upper shell 4 and the lower shell 1 are fixed, the positioning block 33 at the lower end of the upper shell 4 will be inserted into the positioning groove 34 at the upper end of the lower shell 1, thereby improving the fixation reliability of the upper shell 4 and the lower shell 1.

[0032] Specifically, the fixing component 35 includes a spring 351, an adjusting groove 352, an adjusting block 353, and a fixing rod 354. The spring 351 is located inside the lower housing 1 on the side of the slot 36. The fixing rod 354 is located at the other end of the spring 351. The adjusting block 353 is located at the side edge of the fixing rod 354. The lower housing 1 has an adjusting groove 352 corresponding to the adjusting block 353 on its side.

[0033] By adopting the above technical solution, when disassembling the upper housing 4 and the lower housing 1, the adjusting block 353 inside the sliding adjusting groove 352 drives the fixing rod 354 to slide out from the inside of the fixing hole 32 and drive the spring 351 to compress, at which time the upper housing 4 and the lower housing 1 can be disassembled.

[0034] In this embodiment, when it is necessary to connect and fix the upper housing 4 and the lower housing 1, the locking block 31 at the lower end of the upper housing 4 is inserted into the locking groove 36 inside the lower housing 1. With the cooperation of the fixing component 35 and the fixing hole 32, the upper housing 4 and the lower housing 1 can be fixed. When the upper housing 4 and the lower housing 1 are fixed, the positioning block 33 at the lower end of the upper housing 4 will be inserted into the positioning groove 34 at the upper end of the lower housing 1, thereby improving the fixing reliability of the upper housing 4 and the lower housing 1. When disassembling the upper housing 4 and the lower housing 1, the adjusting block 353 inside the sliding adjusting groove 352 is slidable. The adjusting block 353 drives the fixing rod 354 to slide out from the inside of the fixing hole 32 and drives the spring 351 to compress. At this time, the upper housing 4 and the lower housing 1 can be disassembled.

[0035] The structure and operating principle of the fiber optic grating 5, mass block body 7, second elastic element 8, second fixed block 9, second fixed block 10, and first elastic element 11 in this utility model have been disclosed in Chinese patent application No. 201621449599.8, which discloses a compact fiber optic grating accelerometer. Its working principle is that when an object moves, due to inertia, the mass block body 7 will slide forward. The forward sliding of the mass block body 7 will cause the first fixed block 10 and the second fixed block 9 to move closer to each other, and cause the first elastic element 11 and the second elastic element 8 to be compressed. The corresponding fiber optic grating 5 is stretched (or compressed), and the wavelength of the fiber optic grating 5 changes. The wavelength change of the fiber optic grating 5 is monitored in real time by a high-speed wavelength demodulation center to determine the magnitude of the acceleration of the measured object.

[0036] The working principle and usage process of this utility model are as follows: In use, the adhesive layer 2 at the lower end of the lower housing 1 is adhered to the object to be tested. When the object moves, due to inertia, the mass block 7 slides forward. This forward sliding of the mass block 7 causes the first fixed block 10 and the second fixed block 9 to move closer together, compressing the first elastic element 11 and the second elastic element 8. Consequently, the fiber optic grating 5 is stretched (or compressed), causing a change in its wavelength. The wavelength change of the fiber optic grating 5 is monitored in real time by a high-speed wavelength demodulation center to determine the magnitude of the object's acceleration. When the mass block 7 slides due to inertia, the slider 64 slides inside the first slide rail 61. Simultaneously, the slider 64 is rotatably connected to the first pulley 63 via a rotating shaft 62. This reduces the friction of the mass block 7 during sliding, minimizing the impact of factors affecting its movement and thus improving the accuracy of object acceleration detection. When the mass block body 7 slides, the second slide rail 654 will slide and connect with the groove 651. At the same time, the second pulley 652 connected by a pin inside the groove 651 can further improve the sliding effect of the mass block body 7. When it is necessary to connect and fix the upper shell 4 and the lower shell 1, the locking block 31 at the lower end of the upper shell 4 is inserted into the locking groove 36 inside the lower shell 1. With the cooperation of the fixing component 35 and the fixing hole 32, the upper shell 4 and the lower shell 1 can be fixed. When the upper shell 4 and the lower shell 1 are fixed, the positioning block 33 at the lower end of the upper shell 4 will be inserted into the positioning groove 34 at the upper end of the lower shell 1, thereby improving the fixing reliability of the upper shell 4 and the lower shell 1. When disassembling the upper shell 4 and the lower shell 1, the adjusting block 353 inside the sliding adjusting groove 352 is slidable. The adjusting block 353 drives the fixing rod 354 to slide out from the inside of the fixing hole 32 and drives the spring 351 to compress. At this time, the upper shell 4 and the lower shell 1 can be disassembled.

[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 fiber optic accelerometer, comprising a lower housing (1), wherein an adhesive layer (2) is pasted on the lower end face of the lower housing (1), and an upper housing (4) is snapped onto the upper end face of the lower housing (1). A mass block body (7) is slidably connected inside the housing structure formed by the lower housing (1) and the upper housing (4). A second fixing block (9) is connected to one side of the mass block body (7) by screws. A second elastic element (8) is connected to the other end of the second fixing block (9) by screws. A first fixing block (10) is connected to the other end of the second elastic element (8) by screws. A first elastic element (11) is sleeved on the outer surface of the second elastic element (8), the second fixing block (9), and the first fixing block (10). A fiber optic grating (5) is inserted inside the mass block body (7), the second elastic element (8), the second fixing block (9), and the first fixing block (10) and extends outward from the outer side of the housing structure formed by the lower housing (1) and the upper housing (4), characterized in that: The side of the mass block body (7) and the shell structure formed by the lower shell (1) and the upper shell (4) are slidably connected by the mass block sliding mechanism (6), and the lower shell (1) and the upper shell (4) are fixedly connected by the shell fixing mechanism (3).

2. The fiber optic grating accelerometer according to claim 1, characterized in that: The mass block sliding mechanism (6) includes a first slide rail (61), a rotating shaft (62), a first pulley (63), a slider (64), and a side sliding structure (65). The upper end of the mass block body (7) is fixedly connected to the slider (64). The center position of the slider (64) is rotatably connected to the first pulley (63). The two ends of the first pulley (63) are rotatably connected to the slider (64) through the rotating shaft (62). The bottom of the lower shell (1) and the top wall of the upper shell (4) are connected to the first slide rail (61) corresponding to the slider (64). The side of the mass block body (7) is slidably connected to the shell structure composed of the lower shell (1) and the upper shell (4) through the side sliding structure (65).

3. The fiber optic grating accelerometer according to claim 2, characterized in that: The side sliding structure (65) includes a groove (651), a second pulley (652), an embedding groove (653), and a second slide rail (654). The side of the mass block body (7) is provided with a groove (651). The second pulley (652) is rotatably connected to the side of the groove (651) by a pin and extends out of the groove (651). The inside of the mass block body (7) is provided with an embedding groove (653) corresponding to the second pulley (652). The inner walls of the lower shell (1) and the upper shell (4) are provided with a second slide rail (654) corresponding to the groove (651).

4. The fiber optic grating accelerometer according to claim 1, characterized in that: The housing fixing mechanism (3) includes a locking block (31), a fixing hole (32), a fixing component (35), and a locking groove (36). Two sets of locking blocks (31) are provided at the lower diagonal of the upper housing (4), and a locking groove (36) corresponding to the locking block (31) is provided at the upper diagonal of the lower housing (1). A fixing component (35) is provided inside the side of the locking groove (36), and a fixing hole (32) corresponding to the fixing component (35) is provided on the side of the locking block (31).

5. The fiber optic grating accelerometer according to claim 4, characterized in that: The housing fixing mechanism (3) also includes a positioning block (33) and a positioning groove (34). The positioning block (33) is installed at the other two corners at the lower end of the upper housing (4), and the positioning groove (34) corresponding to the positioning block (33) is opened at the other two corners at the upper end of the lower housing (1).

6. The fiber optic grating accelerometer according to claim 4, characterized in that: The fixing component (35) includes a spring (351), an adjustment groove (352), an adjustment block (353), and a fixing rod (354). The side of the slot (36) is located inside the lower housing (1) and a spring (351) is provided. The other end of the spring (351) is provided with a fixing rod (354). An adjustment block (353) is provided at the side edge of the fixing rod (354). The side of the lower housing (1) is provided with an adjustment groove (352) corresponding to the adjustment block (353).

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