A three-component optical fiber detector

Abstract

A three-component optical fiber detector includes an open detector housing at both ends, the two ends of the detector housing are respectively connected to a sealing cover component and a plug component by fasteners, the detector housing is fixed to an internal push-pull module by fasteners, and the internal push-pull module includes an inner housing and three mass block components located in the inner housing, wherein each mass block component includes a mass block fixed on the inner housing at one end and an optical fiber fixed on the mass block at the middle part, and the mass block is divided by a cantilever into a first part connected to the inner housing and a second part capable of swinging with the cantilever; the optical fiber spans the suspension corresponding to the cantilever on the mass block, and is fixed to the first and second parts of the mass block at the same time, so that the part corresponding to the cantilever remains horizontal and without bending; a grating is engraved at the position corresponding to the cantilever of the optical fiber, and the optical fiber at the part where the grating is located can bend with the swing of the cantilever when the mass block senses vibration; the swing directions of the mass block cantilevers in the three mass block module components are perpendicular to each other. The present invention has high vibration recognition capability and low equipment accuracy requirements.

Description

Technical Field

[0001] The invention belongs to the technical field of detectors, and in particular relates to a three-component optical fiber detector. Background Art

[0002] At present, most of the domestic detectors are electric dynamic coil detectors, which have the disadvantages of low detection sensitivity, small dynamic range, difficulty in cascade multiplexing, low transmission rate, etc. Fiber optic detectors can perfectly solve these problems, and also have many advantages such as wide bandwidth, strong anti-electromagnetic interference and signal crosstalk, high temperature and high pressure resistance, etc. In addition, the current more mature fiber optic detectors are expensive. Summary of the invention

[0003] In order to overcome the above-mentioned deficiencies of the prior art, the object of the present invention is to provide a three-component optical fiber detector having the characteristics of high sensitivity, wide measurement bandwidth, easy cascade multiplexing, and resistance to high temperature and high pressure.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A three-component optical fiber detector, comprising a detector housing with two ends opened, the two ends of the detector housing being connected to a sealing cover component and a plug component respectively by fasteners, and the detector housing and an internal push-pull module being fixed by fasteners; characterized in that:

[0006] The inner shell is installed in the detector shell by axial pushing and pulling; the front end of the detector shell is provided with an annular inner protrusion, the outer ring of the front end surface of the inner shell is matched with the rear end surface of the annular inner protrusion to achieve axial limitation, and the annular inner protrusion and the front end surface of the inner shell are fixed by fasteners;

[0007] The internal push-pull module includes an inner shell and a socket component fixed to the inner shell, an anti-loosening fastener, an O-ring, a mass block component 1, a mass block component 2, a mass block component 3, a positioning guide pin, a support column and a mounting plate;

[0008] The mass block component 1, mass block component 2 and mass block component 3 are all composed of an optical fiber contact, an optical fiber and a mass block. Each mass block component includes a mass block fixed on the inner shell at one end and an optical fiber fixed on the mass block in the middle. The mass block is divided by the cantilever into a first part connected to the inner shell and a second part capable of swinging with the cantilever. The optical fiber spans the suspension corresponding to the cantilever on the mass block and is fixed to the first part and the second part of the mass block at the same time, so that the part corresponding to the cantilever remains horizontal and without bending. The position corresponding to the cantilever of the optical fiber is engraved with a grating, and the optical fiber at the part where the grating is located can bend with the swing of the cantilever when the mass block senses fluctuations.

[0009] The rear end of the inner housing is also connected to the mounting plate through a support column, and the two socket housing components are respectively fixed to the front end face of the inner housing and the mounting plate, the support column is connected to the rear end face of the inner housing through threads, and the mounting plate is connected and fixed to the support column through the cooperation of the anti-loosening fastener and the threaded hole on the support column;

[0010] The two ends of the inner housing are provided with socket components, which include a socket housing component, a socket pressure plate and an optical fiber contact. A cavity adapted to the socket pressure plate is provided inside the rear end of the socket housing component, a positioning step is provided on the optical fiber contact, and a step hole matched with the positioning step is provided in the socket pressure plate. The optical fiber contact is fixed in the socket housing component by being pressed by the socket pressure plate through the matching of the positioning step and the step hole on the socket pressure plate.

[0011] The mass block component comprises a mass block with one end fixed on the support frame, an optical fiber with the middle part fixed on the surface of the mass block, and optical fiber contacts connected to the two free ends of the optical fiber extending out of the mass block; the two ends of the optical fiber in each mass block component are respectively connected to the corresponding optical fiber contacts in the socket shell component at the front end and the rear end of the inner shell, and a through hole for the optical fiber to pass through is provided at the corresponding position of the inner shell;

[0012] The inner shell end surface and the mounting plate end surface are both provided with grooves for accommodating the rear end of the socket pressing plate and limiting its axial position;

[0013] The socket housing component is fixed to the inner housing and the end surface of the mounting plate respectively by anti-loosening fasteners;

[0014] The plug component is plugged into the socket component at the end of the internal push-pull module.

[0015] Furthermore, the mass block component one, mass block component two, mass block component three and the inner shell are limited by positioning guide pins, the bottom of the mass block component one is fixed on the bottom wall of the inner shell, and the mass block component two and mass block component three are fixed on the rear end surface of the inner shell.

[0016] Furthermore, the step hole is a U-shaped slot hole with one side open, and the opening size of one side of the U-shaped slot hole is smaller than the internal hole diameter, so that the optical fiber contact can be loaded into the step hole from one side with a wire after the optical fiber is connected and will not fall out from the opening on the side of the step hole.

[0017] Furthermore, a positioning pin installation hole for the positioning pin to pass through is provided on the first part of the mass block, and a corresponding positioning pin installation hole is also provided on the inner shell, and the mass block is fixedly positioned in the inner shell by the positioning pin.

[0018] Furthermore, a cantilever is provided in the mass block, which divides the mass block into a first part connected to the support frame and a second part away from the support frame along the length direction, and the cantilever can drive the second part to swing when vibrated; the optical fiber spans the suspension corresponding to the cantilever on the mass block and is fixed to the first part and the second part of the mass block respectively, so that the part of the optical fiber spanning the suspension remains horizontal and without bending; a grating is engraved on the position corresponding to the cantilever; the optical fiber is located on a surface of the mass block that is perpendicular to the swing direction of the cantilever; the surface of the mass block that is perpendicular to the swing direction of the cantilever is provided with an optical fiber installation groove extending along the length direction, and the optical fiber can be fixed in the optical fiber installation groove on one of the surfaces by bonding as needed.

[0019] Furthermore, the optical fiber contacts at both ends of the optical fiber are finally installed in the socket component, so that the optical fiber detector can be connected to an external device or connected in series with the next optical fiber detector through the cooperation of the socket component and the plug component at either end; that is, the second end of the i-th optical fiber detector is connected to the first end of the i+1-th optical fiber detector through the plug assembly, the second end of the N-th optical fiber detector is connected to the external device through the plug component, and the first end of the first optical fiber detector is sealed by the sealing cover component; the plug assembly includes two plug components adapted to the socket component and a cable connecting the two plug components.

[0020] Furthermore, the inner shell is a cylindrical hollow structure, and the cantilever swing directions of the mass blocks in the mass block components are at angles to each other. When the swing directions of the three mass block components are perpendicular to each other, the optical fiber detector can detect the fluctuation intensity in the three directions of X, Y, and Z; or change the installation position and installation direction of mass block component one, mass block component two, and mass block component three to adjust the swing direction of the cantilever in the mass block, so as to sense the fluctuations transmitted from different directions.

[0021] Furthermore, the plug component is sealed with the inner wall of the detector housing through an O-ring;

[0022] The inner shell and the detector shell are sealed by the cooperation of the O-ring arranged in the O-ring groove on the outer periphery of the inner shell and the inner wall of the detector shell.

[0023] The sealing cover component is composed of a sealing cover and an O-ring. The front end of the sealing cover is provided with a threaded hole for connecting with a device for fixing the geophone. The circumference is provided with screw holes for fixing on the end face of the geophone housing through fasteners. The O-ring cooperates with the inner wall of the geophone housing to play a sealing role.

[0024] The outer periphery of the mounting plate is provided with an O-ring for achieving sealing with the inner wall of the detector housing;

[0025] An O-ring is installed in the O-ring groove on the outer side of the front end of the plug component housing;

[0026] The front end of the plug component shell is inserted into the detector shell and is sealed by cooperating with the inner wall of the detector shell through an O-type sealing ring.

[0027] Furthermore, the front end of the plug component housing and the front end of the sealing cover are consistent in shape and size.

[0028] Furthermore, the plug component includes a plug component shell, a plug optical cable assembly and a tail sheath. The outer periphery of the plug component shell is also provided with a screw hole extending axially, and the screws inserted in the screw hole realize the fixed connection between the plug component shell and the detector shell; the front end of the plug optical cable assembly is docked with the socket component at the end of the internal push-pull module, and the tail is connected to an external device to read and receive optical signals. The tail sheath is a plastic packaging material that is plastic-sealed on the tail of the plug component shell and the optical cable sheath of the plug optical cable assembly to play a sealing and tensile resistance role; the outer side of the plug component shell is also provided with an annular groove to increase the holding force of the tail sheath.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The detector of the present invention uses a fiber Bragg grating as an optical sensor element, and identifies the intensity of fluctuations through a special algorithm based on the strength of the reflected light signal; the detector can be used alone or in series.

[0031] 2. The three-component optical fiber detector of the present invention can detect the fluctuation intensity in three directions of X, Y and Z. It adopts a modular design, and the interior is an integral whole, which is fixed inside the detector housing by fasteners.

[0032] 3. The three-component optical fiber detector of the present invention extracts data in each direction in parallel, which reduces the difficulty of the algorithm and the accuracy requirements of the detection equipment. The two ends use detachable connector interfaces, which are easy to operate and can be replaced at any time.

[0033] 4. When the present invention needs to connect multiple detectors in series, adjacent detectors are directly connected through plugs and connecting wires. The modular design concept does not require additional tools.

[0034] 5. All parts of the present invention are disassembled for easy maintenance, and all materials are commonly used materials with low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a front view of the optical fiber detector of the present invention;

[0036] Figure 2 is a partial cross-sectional view of the optical fiber detector of the present invention;

[0037] Figure 3 It is a schematic diagram of the sealing cover component of the optical fiber detector of the present invention;

[0038] Figure 4 for Figure 3 Side view of

[0039] Figure 5 This is a schematic diagram of the push-pull module structure inside the optical fiber detector of the present invention;

[0040] Figure 6 for Figure 5 Another viewing schematic diagram of ;

[0041] Figure 7 This is a schematic diagram of the inner housing structure of the optical fiber detector of the present invention;

[0042] Figure 8 This is a working principle diagram of the detector of the present invention;

[0043] Fig. 9 It is a schematic diagram of the mass block structure of the present invention;

[0044] Fig.10 It is a schematic diagram of the socket component of the present invention;

[0045] Fig.11 It is a schematic diagram of the socket component of the present invention.

[0046] Fig.12 It is a schematic diagram of the vibration detection effect of the present invention.

[0047] Among them, 1 is a sealing cover component; 2 is a fastener; 3 is an internal push-pull module; 4 is a detector housing; 5 is a plug component; 6 is a sealing cover; 7 is an O-ring; 8 is a socket component; 9 is an anti-loosening fastener; 10 is an inner housing; 11 is an O-ring; 12 is a mass block component one; 13 is a mass block component two; 14 is a mass block component three; 15 is a positioning guide pin; 16 is a support column; 17 is a mounting plate; 18 is a socket housing component; 19 is a socket pressure plate; 20 is a fiber optic contact; 21 is an optical fiber; 22 is a mass block; 23 is an O-ring; 24 is a plug component housing; 25 is a plug optical cable assembly; 26 is a tail sheath; 27 is a grating; 28 is a fiber optic mounting groove; 29 is a positioning pin mounting hole; 30 is a positioning step; 31 is a step hole; 32 is a groove; 33 is an inner protrusion; 34 is a threaded hole. DETAILED DESCRIPTION

[0048] The present invention will be further described below with reference to the accompanying drawings, i.e., embodiments.

[0049] like Figure 1-11As shown in the figure, it is a schematic diagram of the structure of each part of the fiber optic detector of the present invention. The fiber optic detector includes a mass block component for detecting single-direction fluctuations. The mass block component includes a mass block 22 fixed on a support frame at one end, an optical fiber 21 fixed on the surface of the mass block 22 in the middle part, and an optical fiber contact 20 connected to the two free ends of the optical fiber 21 extending out of the mass block 22.

[0050] The mass block 22 is provided with a cantilever 223, which divides the mass block 22 into a first part 221 connected to the support frame and a second part 222 away from the support frame along the length direction, and the cantilever 223 can drive the second part 222 to swing when vibrated.

[0051] The optical fiber 21 spans the suspended space corresponding to the cantilever 223 on the mass block 22 and is fixedly connected to the first part 221 and the second part 222 of the mass block respectively, so that the part of the optical fiber 21 spanning the suspended space remains horizontal and without bending, thereby enabling the part of the optical fiber 21 corresponding to the cantilever 223 to bend when the cantilever 223 swings. The grating 27 is engraved on the position corresponding to the cantilever 223 of the optical fiber 21, so that when the mass block 22 senses vibration, its second part 222 swings in a fixed direction through the cantilever 223 and drives the optical fiber 21 located above the cantilever to bend. The bending movement of this part of the optical fiber 21 causes the central wavelength of the fiber grating at this position to drift, and the vibration intensity can be determined by reading the optical signal through an external device. In the embodiment of the present invention, a femtosecond laser is used to write the grating.

[0052] In the embodiment of the present invention, the optical fiber 21 is located on a surface of the mass block 22 that is perpendicular to the swing direction of the cantilever 223. Preferably, the surfaces of the mass block 22 that are perpendicular to the swing direction of the cantilever are all provided with optical fiber installation grooves 28 extending along the length direction, and the optical fiber can be fixed in the optical fiber installation groove 28 on one of the surfaces by bonding as needed.

[0053] The optical fiber contacts 20 connected to both ends of the optical fiber 21 are finally installed in the socket component 8, so that the optical fiber detector can be connected to an external device or connected in series with the next optical fiber detector through the cooperation of the socket component 8 and the plug component 5 at either end.

[0054] In an embodiment of the present invention, the fiber optic detector is a three-component fiber optic detector that can detect the fluctuation intensity in three directions of X, Y, and Z. In this embodiment, the support frame is a cylindrical inner shell 10, and the inner shell 10 is a hollow structure. Three mass block components are fixed therein, namely, mass block component one 12, mass block component two 13, and mass block component three 14, wherein the swing directions of the above three mass block components are perpendicular to each other, thereby enabling the fiber optic detector to detect the fluctuation intensity in three directions.

[0055] The mass block component 1 12 , mass block component 2 13 , and mass block component 3 14 are all composed of an optical fiber contact 20 , an optical fiber 21 , and a mass block 22 , and the only difference between them is the length of the optical fiber and the size ratio of the mass block.

[0056] In this embodiment, the first part of the mass block 22 is provided with a positioning pin installation hole 29 for the positioning pin 15 to pass through, and the inner shell 10 is also provided with a corresponding positioning pin installation hole, so that the mass block 22 of the present invention is fixedly positioned in the inner shell 10 through the positioning pin 15. That is, the mass block component 1 12, the mass block component 2 13, the mass block component 3 14 and the inner shell 10 of the present invention are limited by positioning guide pins to ensure the relative positions of the mass block component 1 12, the mass block component 2 13, the mass block component 3 14 and the inner shell 10. Preferably, the bottom of the mass block component 1 12 is fixed to the bottom wall of the inner shell, and can swing left and right relative to the inner shell, and the mass block component 2 13 and the mass block component 3 14 are both fixed to the rear end surface of the inner shell 10, and can swing up and down and forward and backward respectively relative to the inner shell, but it is not limited to this.

[0057] The present invention can adjust the swing direction of the cantilever in its mass block by changing the installation position and installation direction of mass block component 1 12 , mass block component 2 13 and mass block component 3 14 , so as to sense the fluctuations coming from different directions.

[0058] Both ends of the inner shell 10 are also provided with a socket component 8, and the socket component 8 includes a socket shell component 18, a socket pressure plate 19 and a fiber optic contact 20. The fiber optic contact 20 is a fiber optic contact 20 in the mass block component connected to the optical fiber 21, that is, the two ends of the optical fiber in each mass block component are respectively connected to the corresponding fiber optic contact 20 in the socket shell component 18 at the front and rear ends of the inner shell, and the corresponding position of the inner shell 10 is provided with a through hole for the optical fiber 21 to pass through, so that the fiber optic detector can be connected to an external device or connected in series between different fiber optic detectors through the socket component at either end.

[0059] In the embodiment of the present invention, since the mass block component two 13 and the mass block component three 14 are both fixed on the rear end face of the inner shell, the rear end of the inner shell of the present invention is also connected to the mounting plate 17 through the support column 16. At this time, the two socket shell components 18 are respectively fixed on the front end face of the inner shell and the mounting plate 17. The support column 16 is connected to the rear end face of the inner shell 10 through threads, and the mounting plate 17 is connected and fixed to the support column 16 through the cooperation of the anti-loosening fastener 9 and the threaded hole on the support column 16.

[0060] The rear end of the socket housing component 18 is provided with a cavity adapted to the socket pressing plate 19, the optical fiber contact 20 is provided with a positioning step 30, and the socket pressing plate 19 is provided with a step hole 31 that matches the positioning step 30. The optical fiber contact 20 is pressed and fixed in the socket housing component 18 by the socket pressing plate 19 through the matching of the positioning step 30 on it and the step hole 31 on the socket pressing plate 19. The step hole 31 is a U-shaped slot hole with one side open, and the opening size of one side of the U-shaped slot hole is smaller than the internal aperture, so that the optical fiber contact 20 can be loaded into the step hole from one side with a line after the optical fiber 21 is connected and will not fall out from the opening on the side of the step hole. The end face of the inner housing 10 or the end face of the mounting plate 17 is provided with a groove 32 for accommodating the rear end of the socket pressing plate and axially limiting it. After the socket pressing plate and the optical fiber contact are assembled, the socket housing component 18 is fixed to the end face of the inner housing 10 or the mounting plate 17 by the anti-loosening fastener 9, thereby completing the overall fixation of the socket component.

[0061] The optical fiber detector of the present invention further comprises a detector housing 4 with two ends open, the inner housing 10 is installed in the detector housing 4 by axial push and pull, and the O-ring 11 arranged in the O-ring groove on its outer periphery cooperates with the inner wall of the detector housing 4 to achieve sealing between the two. The front end of the detector housing 4 is provided with an annular inner protrusion 33, and the outer ring of the front end face of the inner housing 10 cooperates with the rear end face of the annular inner protrusion 33 to achieve axial limitation, and the annular inner protrusion 33 and the front end face of the inner housing 10 are also fixedly connected by a fastener 2. In the embodiment of the present invention, the outer periphery of the mounting plate 17 is also provided with an O-ring for achieving sealing with the inner wall of the detector housing 4. That is, the inner shell 10 and the socket component 8, O-ring 11, mass block component 1 12, mass block component 2 13, mass block component 3 14, positioning guide pin 15, support column 16 and mounting plate 17 fixed on the inner shell 10 together constitute an internal push-pull module 3 that is assembled and disassembled with the detector housing 4 through axial push-pull, and the front end of the detector housing 4 is provided with a fastener 2 for fixing with the internal push-pull module 3.

[0062] In other embodiments of the present invention, the inner shell 10 is provided with more than three mass block components, and the cantilever swing directions of the mass blocks in the above-mentioned mass block components are at angles to each other, and the swing directions of the three cantilevers are perpendicular to each other, thereby ensuring that the three-component detector can not only perform vibration detection in the three directions of X, Y, and Z, but also perform vibration detection at other spatial angles, so that the detection result is more accurate.

[0063] The detector end of the present invention is also provided with a plug component 5 for realizing the connection with other detectors of external devices. The plug component 5 is fixed to the end of the detector housing 4 by a fastener 2 and plugged into the socket component 8 at the end of the internal push-pull module 3. The plug component 5 is also sealed with the inner wall of the detector housing 4 by an O-ring 23. Specifically, the plug component 5 includes a plug component housing 24, a plug optical cable assembly 25 and a tail sheath 26, wherein an O-ring 23 is installed in the O-ring groove on the outer front end of the plug component housing 24, and the front end of the plug component housing 24 is inserted into the detector housing 4 and sealed by the O-ring 23 and the inner wall of the detector housing 4. The outer periphery of the plug component housing 24 is also provided with a screw hole extending in the axial direction, and the screws inserted in the screw hole realize the fixed connection between the plug component housing 24 and the detector housing 4. The front end of the plug optical cable assembly 25 is connected to the socket component 8 at the end of the internal push-pull module 3, and the tail is connected to the external device to read and send and receive optical signals. The tail sheath 26 is a plastic sealing material that is plastic-sealed on the tail of the plug component housing 24 and the optical cable sheath of the plug optical cable assembly 25 to play a sealing and tensile resistance role. The outer side of the plug component housing 24 is also provided with an annular groove to increase the holding force of the tail sheath 26.

[0064] The optical fiber detector of the present invention is also provided with a sealing cover component 1 for sealing the end thereof. The sealing cover component 1 is fixed to the end face of the detector housing by a fastener 2 and is sealed with the detector housing by a sealing ring. Specifically, the sealing cover component 1 is composed of a sealing cover 6 and an O-ring 7. The front end of the sealing cover 6 is provided with a threaded hole 34 for connecting with a device for fixing the detector. The circumference is provided with screw holes for fixing to the end face of the detector housing 4 by fasteners 2. The O-ring 7 cooperates with the inner wall of the detector housing 4 to play a sealing role. The front end of the housing of the plug component of the present invention and the front end of the sealing cover 6 have completely identical shapes and sizes, so that when the plug component and the sealing cover component of the detector of the present invention are installed, there is no need to distinguish the installation ends, and blind installation can be performed.

[0065] When the optical fiber detector of the present invention is used alone, one end thereof is sealed by a sealing cover component, and the other end thereof is connected to an external device by a plug component.

[0066] When n detectors of the present invention are used in series, the first end of the first detector is sealed by a sealing cover component, and the other end is connected in series with the second detector through two plug components whose tails are connected by cables. The second end of the i-th (i is greater than 1) detector is connected to the first end of the i+1-th detector through two plug components whose tails are connected by cables, and the second end of the n-th detector is connected to an external device.

[0067] In order to verify the beneficial effects of the present invention, the inventors conducted the following experiments using the embodiments:

[0068] Fix the fiber optic three-component detector on a horizontal table, connect the fiber to the SM130 demodulator of Weiguang Company, and detect the vibration signal in real time. Use your finger to knock on the table three times at a distance of 50cm from the detector to collect the corresponding vibration signal. The results are as follows: Fig.12 .

[0069] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with the profession 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 simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A three-component optical fiber detector, comprising a detector housing with two ends open, the two ends of the detector housing being connected to a sealing cover component and a plug component respectively by fasteners, and the detector housing and an internal push-pull module being fixed by fasteners; characterized in that: The inner shell is installed in the detector shell by axial pushing and pulling; the front end of the detector shell is provided with an annular inner protrusion, the outer ring of the front end surface of the inner shell is matched with the rear end surface of the annular inner protrusion to achieve axial limitation, and the annular inner protrusion and the front end surface of the inner shell are fixed by fasteners; The internal push-pull module includes an inner shell and a socket component fixed to the inner shell, an anti-loosening fastener, an O-ring, a mass block component 1, a mass block component 2, a mass block component 3, a positioning guide pin, a support column and a mounting plate; The mass block component 1, mass block component 2 and mass block component 3 are all composed of an optical fiber contact, an optical fiber and a mass block. Each mass block component includes a mass block fixed on the inner shell at one end and an optical fiber fixed on the mass block in the middle. The mass block is divided by the cantilever into a first part connected to the inner shell and a second part capable of swinging with the cantilever. The optical fiber spans the suspension corresponding to the cantilever on the mass block and is fixed to the first part and the second part of the mass block at the same time, so that the part corresponding to the cantilever remains horizontal and without bending. The position corresponding to the cantilever of the optical fiber is engraved with a grating, and the optical fiber at the part where the grating is located can bend with the swing of the cantilever when the mass block senses fluctuations. The rear end of the inner housing is also connected to the mounting plate through a support column, and the two socket housing components are respectively fixed to the front end face of the inner housing and the mounting plate, the support column is connected to the rear end face of the inner housing through threads, and the mounting plate is connected and fixed to the support column through the cooperation of the anti-loosening fastener and the threaded hole on the support column; The two ends of the inner housing are provided with socket components, which include a socket housing component, a socket pressure plate and an optical fiber contact. A cavity adapted to the socket pressure plate is provided inside the rear end of the socket housing component, a positioning step is provided on the optical fiber contact, and a step hole matched with the positioning step is provided in the socket pressure plate. The optical fiber contact is fixed in the socket housing component by being pressed by the socket pressure plate through the matching of the positioning step and the step hole on the socket pressure plate. The mass block component comprises a mass block with one end fixed on the support frame, an optical fiber with the middle part fixed on the surface of the mass block, and optical fiber contacts connected to the two free ends of the optical fiber extending out of the mass block; the two ends of the optical fiber in each mass block component are respectively connected to the corresponding optical fiber contacts in the socket shell component at the front end and the rear end of the inner shell, and a through hole for the optical fiber to pass through is provided at the corresponding position of the inner shell; The inner shell end surface and the mounting plate end surface are both provided with grooves for accommodating the rear end of the socket pressing plate and limiting its axial position; The socket housing component is fixed to the inner housing and the end surface of the mounting plate respectively by anti-loosening fasteners; The plug component is plugged into the socket component at the end of the internal push-pull module.

2. A three-component optical fiber detector according to claim 1, characterized in that: The mass block component 1, mass block component 2, mass block component 3 and the inner shell are limited by positioning guide pins, the bottom of the mass block component 1 is fixed on the bottom wall of the inner shell, and the mass block component 2 and mass block component 3 are fixed on the rear end surface of the inner shell.

3. A three-component optical fiber detector according to claim 1, characterized in that: The step hole is a U-shaped slot hole with one side open, and the opening size of one side of the U-shaped slot hole is smaller than the internal aperture, so that the optical fiber contact piece can be loaded into the step hole from one side with the wire after the optical fiber is connected and will not fall out from the opening on the side of the step hole.

4. A three-component optical fiber detector according to claim 1, characterized in that: The first part of the mass block is provided with a positioning pin installation hole for the positioning pin to pass through, and the inner shell is also provided with a corresponding positioning pin installation hole. The mass block is fixedly positioned in the inner shell by the positioning pin.

5. A three-component optical fiber detector according to claim 1, characterized in that: A cantilever is provided in the mass block, which divides the mass block into a first part connected to a support frame and a second part away from the support frame along the length direction, and the cantilever can drive the second part to swing when vibrated; the optical fiber spans the suspension corresponding to the cantilever on the mass block and is fixed to the first part and the second part of the mass block respectively, so that the part of the optical fiber spanning the suspension remains horizontal and without bending; a grating is engraved on the position corresponding to the cantilever; the optical fiber is located on a surface of the mass block that is perpendicular to the swing direction of the cantilever; the surface of the mass block that is perpendicular to the swing direction of the cantilever is provided with an optical fiber installation groove extending along the length direction, and the optical fiber can be fixed in the optical fiber installation groove on one of the surfaces by bonding as needed.

6. A three-component optical fiber detector according to claim 1, characterized in that: The optical fiber contacts at both ends of the optical fiber are finally installed in the socket component, so that the optical fiber detector can be connected to an external device or connected in series with the next optical fiber detector through the cooperation of the socket component and the plug component at either end; that is, the second end of the i-th optical fiber detector is connected to the first end of the i+1-th optical fiber detector through the plug assembly, the second end of the N-th optical fiber detector is connected to the external device through the plug component, and the first end of the first optical fiber detector is sealed by the sealing cover component; the plug assembly includes two plug components adapted to the socket component and a cable connecting the two plug components.

7. A three-component optical fiber detector according to claim 1, characterized in that: The inner shell is a cylindrical hollow structure, and the cantilever swing directions of the mass blocks in the mass block component are at angles to each other. When the swing directions of the three mass block components are perpendicular to each other, the optical fiber detector can detect the fluctuation intensity in the three directions of X, Y, and Z; or change the installation position and installation direction of mass block component one, mass block component two, and mass block component three to adjust the swing direction of the cantilever in the mass block, so as to sense the fluctuations transmitted from different directions.

8. A three-component optical fiber detector according to claim 1, characterized in that: The plug component is also sealed with the inner wall of the detector housing through an O-ring; The inner shell and the detector shell are sealed by the cooperation of the O-ring arranged in the O-ring groove on the outer periphery of the inner shell and the inner wall of the detector shell; The sealing cover component is composed of a sealing cover and an O-ring. The front end of the sealing cover is provided with a threaded hole for connecting with a device for fixing the geophone. The circumference is provided with screw holes for fixing on the end face of the geophone housing through fasteners. The O-ring cooperates with the inner wall of the geophone housing to play a sealing role. The outer periphery of the mounting plate is provided with an O-ring for achieving sealing with the inner wall of the detector housing; An O-ring is installed in the O-ring groove on the outer side of the front end of the plug component housing; The front end of the plug component shell is inserted into the detector shell and is sealed by cooperating with the inner wall of the detector shell through an O-type sealing ring.

9. A three-component optical fiber detector according to claim 1, characterized in that: The front end of the plug component shell and the front end of the sealing cover are consistent in shape and size.

10. The three-component optical fiber detector according to claim 1, characterized in that: The plug component includes a plug component shell, a plug optical cable assembly and a tail sheath. The outer periphery of the plug component shell is also provided with a screw hole extending in the axial direction. The screws inserted in the screw holes realize the fixed connection between the plug component shell and the detector shell. The front end of the plug optical cable assembly is docked with the socket component at the end of the internal push-pull module, and the tail is connected to an external device to read and receive optical signals. The tail sheath is a plastic sealing material that is plastic-sealed on the tail of the plug component shell and the optical cable sheath of the plug optical cable assembly to play a sealing and tensile resistance role. The outer side of the plug component shell is also provided with an annular groove to increase the holding force of the tail sheath.

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