Fiber optic hydrophone array with hydrophone element biasing

Abstract

The application discloses a hydrophone element offset fiber-optic hydrophone array, which comprises a layer cable, an outer protective sleeve, a support framework assembly and a hydrophone element, the outer protective sleeve is sleeved outside the layer cable, the support framework assembly is arranged in the outer protective sleeve, the hydrophone element is arranged in the outer protective sleeve and comprises a clamping framework and a sensitive cylinder body with a detection optical fiber, the clamping main body and the pressure cable cover body of the clamping framework are arranged on opposite sides of the layer cable and are detachably connected through a first fastener, a disc fiber cavity is formed in the clamping main body and used for extending the detection optical fiber and transmission optical fibers in an optical fiber tube, the sensitive cylinder body and the clamping main body are arranged on the same side of the layer cable and are end-to-end connected, so that the hydrophone element is arranged in an offset mode on the layer cable, and a section of the layer cable, in which the hydrophone element is arranged, is arranged in an offset mode in the outer protective sleeve, compared with cutting the layer cable to replace the hydrophone element, the application obviously simplifies maintenance work and improves maintenance efficiency.

Description

Technical Field

[0001] This invention belongs to the field of optical sensing detection system technology, and particularly relates to an optical fiber hydrophone array with hydrophone element bias. Background Technology

[0002] A fiber optic hydrophone is an underwater acoustic signal sensor based on fiber optic and optoelectronic technologies. It converts underwater acoustic vibrations into optical signals through highly sensitive optical coherent detection, which are then transmitted via optical fiber to a signal processing system to extract the acoustic signal information. It features high sensitivity and good frequency response characteristics, and because it uses optical fiber as the information carrier, it is suitable for long-distance, large-area monitoring.

[0003] Currently, fiber optic hydrophones and their arrays have become the development direction of the underwater portion of passive sonar, and are the most promising equipment for ocean detection and listening to weak sound field signals. A typical fiber optic hydrophone array is based on a central stranded cable, and to control the array's outer diameter, the hydrophone elements are designed with coaxial perforations to allow the central stranded cable to pass through. However, when a hydrophone element in the middle of the array fails, it is difficult to repair, requiring the central stranded cable to be cut for replacement. Subsequent addition of array segment connectors is also necessary to reconnect the cut central stranded cable, making the work quite cumbersome. Summary of the Invention

[0004] To address the aforementioned defects or deficiencies, this invention provides a fiber optic hydrophone array with biased hydrophone elements, aiming to solve the technical problem of cumbersome maintenance work caused by the need to cut the central layer stranded cable when replacing hydrophone elements.

[0005] To achieve the above objectives, the present invention provides a fiber optic hydrophone array with biased hydrophone elements. The array includes a stranded cable, an outer protective sleeve, a support frame assembly, and hydrophone elements. The stranded cable includes a stranded optical fiber tube and tensile metal wires. The outer protective sleeve is fitted over the outside of the stranded cable. The support frame assembly is located inside the outer protective sleeve and supports the stranded cable. The hydrophone elements are placed inside the outer protective sleeve and include a clamping frame and a sensitive cylinder with a detection optical fiber wound around it. The clamping frame includes a clamping body and a cable clamping cover. The clamping body and the cable clamping cover are located on opposite sides of the stranded cable and are detached and connected by a first fastener. The clamping body has a fiber-coil cavity for the detection optical fiber and the transmission optical fiber in the optical fiber tube to extend into. The sensitive cylinder and the clamping body are located on the same side of the stranded cable and are endo-connected, so that the hydrophone elements are biased on the stranded cable, and the section of stranded cable containing the hydrophone elements is biased within the outer protective sleeve.

[0006] In one embodiment of the present invention, the end face of the clamping body is provided with a fastening hole, the sensitive cylinder includes a detection body and a positioning post, the first end of the positioning post is fastened through the fastening hole, the detection body is wound with a detection optical fiber and the end is sleeved on the second end of the positioning post, and the detection body and the second end of the positioning post are fastened together by at least two second fasteners, and the at least two second fasteners are arranged sequentially at intervals along the circumference of the detection body.

[0007] In one embodiment of the present invention, the detection body includes a main body section, a fiber-passing section, and a connecting section arranged coaxially along the length direction of the stranded cable. A detection optical fiber is wound around the outer side of the main body section. The outer diameter of the fiber-passing section is larger than the outer diameter of the detection optical fiber wound on the main body section. The outer diameter of the connecting section is larger than the outer diameter of the fiber-passing section. The connecting section is sleeved on the second end of the positioning post and fastened by at least two second fasteners. A fiber-passing groove is opened on the outer periphery of the fiber-passing section for the detection optical fiber to extend into the connecting section. The end face of the clamping body is provided with a detection fiber inlet hole in the coverage area of ​​the connecting section so that the detection optical fiber extending from the connecting section can pass through the detection fiber inlet hole and enter the fiber coil cavity.

[0008] In one embodiment of the present invention, the end face of the connecting section opposite to the fiber passage section extends out and is provided with a fiber outlet connector. The inner cavity of the fiber outlet connector is connected to the fiber passage groove. The fiber outlet connector is inserted into the fiber inlet detection hole, and an O-ring seal is formed between the fiber outlet connector and the fiber inlet detection hole.

[0009] In one embodiment of the present invention, the clamping body includes a main cavity shell and a sealing cover. The main cavity shell and the cable pressing cover are respectively disposed on opposite sides of the stranded cable and are detached and connected by a first fastener. On the side of the main cavity shell away from the cable pressing cover, a cover space and an axial stop are sequentially provided along the length direction of the stranded cable. The side of the axial stop away from the cover space is set as the end face of the main cavity shell. The sensitive cylinder is connected to the end face of the main cavity shell where the axial stop is located. The fiber coil cavity is disposed on the main cavity shell, and the sealing opening of the fiber coil cavity is disposed on the side of the main cavity shell away from the cable pressing cover, corresponding to the cover space. The sealing cover is placed in the cover space and its end abuts against the axial stop. The sealing cover is detached and connected to the main cavity shell to seal the sealing opening.

[0010] In one embodiment of the present invention, a sealing groove for accommodating a sealing ring is provided around the periphery of the sealing opening.

[0011] In one embodiment of the present invention, the cable pressing cover and the main cavity shell are detachably assembled to form a cable through hole for the layered stranded cable to pass through, and the end face of the cable pressing cover facing the sensitive cylinder is assembled with the end face of the main cavity shell where the axial stop part is located to form a circular end face.

[0012] In one embodiment of the present invention, the sealing cover is fitted to the side of the main cavity shell with the sealing opening, and the side of the sealing cover away from the sealing opening has an installation plane extending along the length direction of the stranded cable. The installation plane has a connection hole for the rod of the third fastener to pass through and connect to the main cavity shell, and the head of the third fastener is fitted to the installation plane.

[0013] In one embodiment of the present invention, the support frame assembly includes a coaxial support frame, an eccentric support frame, and a dielectric filling layer. The outer protective sleeve includes a basic segment and a spacer segment. Both ends of the basic segment are spacer segments. The hydrophone basic element is disposed within the basic segment. The basic segment has an eccentric support frame clamped on the stranded cable on both sides of the hydrophone basic element. The central axis of the eccentric support frame is biased toward the side where the clamping body is located. The spacer segment has a coaxial support frame clamped on the stranded cable. The central axis of the coaxial support frame is collinear with the central axis of the stranded cable. The dielectric filling layer is used to fill the outer protective sleeve, so that the basic segment and the stranded cable are coaxial and the central axis of the basic segment is biased toward the side of the stranded cable where the clamping body is located.

[0014] In one embodiment of the present invention, the support frame assembly further includes an adhesive injection connector, which has a connector through hole for the stranded cable to pass through, and one end of the adhesive injection connector is inserted into the end of the spacer section, and the other end extending out of the spacer section is provided with an adhesive injection port for injecting adhesive into the outer protective sleeve to form a medium filling layer.

[0015] In one embodiment of the present invention, two opposite end faces of the clamping body are provided with transmission fiber inlet holes, and the transmission fiber inlet holes are provided with tube bundle docking components. The tube bundle docking components include hollow screws, washers and gaskets that are sequentially sleeved on the optical fiber tubes cut off in the stranded cable. The hollow screws are tightened and installed on the transmission fiber inlet holes so that the transmission optical fiber in the optical fiber tubes enters the fiber coil cavity.

[0016] In one embodiment of the present invention, the number of optical fiber tubes in the stranded cable is at least two. The at least two optical fiber tubes include a first optical fiber tube and a second optical fiber tube, which extend into the fiber coil cavity from opposite ends of the clamping body, respectively. The first optical fiber tube and the transmission optical fiber inside the tube are first cut off on the outside of the first end of the clamping body. The first optical fiber tube is cut off on the outside of the second end of the clamping body, and the transmission optical fiber inside the first optical fiber tube extends into the fiber coil cavity from the second end of the clamping body. The second optical fiber tube and the transmission optical fiber inside the tube are first cut off on the outside of the second end of the clamping body. The second optical fiber tube is cut off on the outside of the first end of the clamping body, and the transmission optical fiber inside the second optical fiber tube extends into the fiber coil cavity from the first end of the clamping body.

[0017] Through the above technical solution, the fiber optic hydrophone array with biased hydrophone elements provided by the present invention has the following beneficial effects:

[0018] When using the aforementioned biased fiber optic hydrophone array, the hydrophone element includes a clamping frame and a sensitive cylinder with a probe fiber wound around it. The clamping body and cable clamping cover of the clamping frame are located on opposite sides of the stranded cable and are connected and disassembled using a first fastener. The clamping body has a fiber optic cavity for the probe fiber and the transmission fiber in the fiber optic tube to extend into. The sensitive cylinder and clamping body are located on the same side of the stranded cable and are endo-connected, so that the hydrophone element is biased on the stranded cable, and the section of stranded cable containing the hydrophone element is biased within the outer protective sleeve. Through this arrangement, on the one hand, it is possible to… Without increasing the outer diameter of the optical hydrophone array, the hydrophone element can be installed on the stranded cable. On the other hand, since the sensitive cylinder in the hydrophone element is not sleeved on the stranded cable, and the clamping frame is detachably clamped on the stranded cable, when the hydrophone element needs to be replaced, only the corresponding outer protective sleeve and support frame assembly need to be removed. The hydrophone element can be replaced by disassembling and assembling the hydrophone element. After the hydrophone element is replaced, repair can be performed. Compared with the existing technology that requires cutting the stranded cable to replace the hydrophone element, it will obviously simplify the maintenance work and improve the maintenance efficiency.

[0019] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. Those skilled in the art can obtain other drawings based on the structures shown in these drawings without any inventive effort. In the drawings:

[0021] Figure 1 This is a schematic diagram of the structure of a fiber optic hydrophone array with hydrophone element biasing according to an embodiment of the present invention.

[0022] Figure 2 This is a partial structural schematic diagram of a fiber optic hydrophone array with hydrophone element biasing according to an embodiment of the present invention.

[0023] Figure 3 This is a cross-sectional structural schematic diagram of a hydrophone element according to an embodiment of the present invention;

[0024] Figure 4 This is an exploded structural diagram of a hydrophone element according to an embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures:

[0026] 100. Stranded cable; 101. First optical fiber tube; 102. Second optical fiber tube; 200. Outer protective sleeve; 210. Element segment; 220. Spacing segment; 300. Support frame assembly; 310. Coaxial support frame; 320. Eccentric support frame; 330. Dielectric filling layer; 340. Glue-filling connector; 341. Glue-filling port; 400. Clamping frame; 410. Clamping body; 411. Main body cavity shell; 412. Sealing cover; 413. Fiber coil cavity; 414. Fastening hole; 415. Detection fiber inlet hole; 416. Shaft 417. Stop; 418. Sealing ring; 419. Mounting plane; 420. Fiber inlet port; 430. Cable clamping cover; 440. First fastener; 450. Cable through hole; 460. Third fastener; 461. Tube bundle docking assembly; 462. Hollow screw; 463. Washer; 500. Sensitive cylinder; 510. Detector body; 511. Main body section; 512. Fiber passage section; 513. Connecting section; 514. Fiber passage groove; 515. Fiber outlet connector; 520. Positioning post; 530. Second fastener. Detailed Implementation

[0027] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0028] The following description, with reference to the accompanying drawings, describes a fiber optic hydrophone array with biased hydrophone elements according to the present invention.

[0029] like Figures 1 to 3 As shown, the present invention provides a fiber optic hydrophone array with biased hydrophone elements, wherein the fiber optic hydrophone array with biased hydrophone elements includes:

[0030] The stranded cable 100 includes a stranded optical fiber tube and tensile metal wires;

[0031] The outer protective sleeve 200 is fitted onto the outside of the stranded cable 100;

[0032] The support frame assembly 300 is located inside the outer protective sleeve 200 and is used to support the stranded cable 100.

[0033] The hydrophone unit is placed inside the outer protective sleeve 200 and includes a clamping frame 400 and a sensitive cylinder 500 with a detection optical fiber wound around it. The clamping frame 400 includes a clamping body 410 and a cable clamping cover 420. The clamping body 410 and the cable clamping cover 420 are respectively located on opposite sides of the stranded cable 100 and are connected and disassembled by a first fastener 430. The clamping body 410 has a fiber optic cavity 413 for the detection optical fiber and the transmission optical fiber in the fiber optic tube to extend into. The sensitive cylinder 500 and the clamping body 410 are located on the same side of the stranded cable 100 and are connected end-to-end, so that the hydrophone unit is offset on the stranded cable 100 and the section of the stranded cable 100 where the hydrophone unit is located is offset inside the outer protective sleeve 200.

[0034] When using the aforementioned fiber optic hydrophone array with biased hydrophone elements, the hydrophone element includes a clamping frame 400 and a sensitive cylinder 500 with a detection fiber wound around it. The clamping body 410 and the cable clamping cover 420 of the clamping frame 400 are respectively located on opposite sides of the stranded cable 100 and are detached and connected via a first fastener 430. The clamping body 410 has a fiber optic cavity 413 for the detection fiber and the transmission fiber in the fiber optic tube to extend into. The sensitive cylinder 500 and the clamping body 410 are located on the same side of the stranded cable 100 and are endo-connected, so that the hydrophone element is biased on the stranded cable 100, and the section of the stranded cable 100 containing the hydrophone element is biased within the outer protective sleeve 200. Therefore, through… The above configuration allows for the installation of the hydrophone unit on the stranded cable 100 without increasing the outer diameter of the optical hydrophone array. Furthermore, since the sensitive cylinder 500 in the hydrophone unit is not fitted onto the stranded cable 100, and the clamping frame 400 is detachably clamped onto the stranded cable 100, when the hydrophone unit needs replacement, only the corresponding outer protective sleeve 200 and support frame assembly 300 need to be removed. The hydrophone unit can then be replaced by disassembling and assembling it. Repair can then be performed after the hydrophone unit is replaced. Compared to the existing technology that requires cutting the stranded cable 100 to replace the hydrophone unit, this significantly simplifies maintenance work and improves maintenance efficiency.

[0035] It should be noted that, due to the extreme fragility of the sensing optical fiber, the portion of the sensing cylinder 500 where the sensing optical fiber is wound is typically designed as a single-piece structure. Therefore, if the sensing cylinder 500 is to be installed over the stranded cable 100, the stranded cable 100 must be cut to replace the hydrophone unit. Furthermore, because the clamping body 410 of the clamping frame 400 requires a fiber coil cavity 413, the cross-sectional area of ​​the clamping body 410 will inevitably be much larger than the cross-sectional area of ​​the cable clamping cover 420—at least twice as large.

[0036] Furthermore, the offset arrangement of the hydrophone element on the stranded cable 100 mentioned in this invention means that the central axes of the clamping frame 400 and the sensitive cylinder 500 are not collinear with the central axis of the stranded cable 100, but are both located on the same side of the central axis of the stranded cable 100. The sensitive cylinder 500 is offset so that it is located on opposite sides of the outer protective sleeve 200 from the stranded cable 100, without the need for a sleeve installation outside the stranded cable 100. The clamping frame 400 is offset to provide sufficient space for docking with the sensitive cylinder 500. The offset arrangement of the stranded cable 100 containing the hydrophone element in the outer protective sleeve 200 mentioned in this invention means that the central axis of the stranded cable 100 containing the hydrophone element is not collinear with the central axis of the outer protective sleeve 200 containing the hydrophone element. Instead, the central axis of the stranded cable 100 and the central axis of the hydrophone element are located on opposite sides of the central axis of the outer protective sleeve 200. This is to avoid increasing the outer diameter of the outer protective sleeve 200 (fiber optic hydrophone array).

[0037] See Figures 1 to 4 In one embodiment of the present invention, the end face of the clamping body 410 is provided with a fastening hole 414, and the sensitive cylinder 500 includes a detection body 510 and a positioning post 520. The first end of the positioning post 520 is fastened through the fastening hole 414. Specifically, the fastening hole 414 can be a threaded hole, and the first end of the positioning post can be provided with an external thread section that is threaded to the threaded hole, thereby enabling the positioning post 520 to be disassembled and connected to the clamping body 410. A detection optical fiber is wound around the detection body 510 and its end is sleeved on the second end of the positioning post 520. The detection body 510 and the second end of the positioning post 520 are fastened together by at least two second fasteners 530, which are arranged sequentially at intervals along the circumference of the detection body 510. The addition of positioning post 520 and at least two second fasteners 530 can facilitate the disassembly and connection of the detection body 510 and the clamping body 410, and can also prevent the detection body 510 from rotating, thereby ensuring the reliability of the detection fiber winding.

[0038] In one embodiment of the present invention, the detection body 510 includes a main body section 511, a fiber-passing section 512, and a connecting section 513 arranged coaxially along the length direction of the stranded cable 100. A detection optical fiber is wound around the outer side of the main body section 511. Further, the length of the main body section 511 is much greater than the length of the fiber-passing section 512 and the connecting section 513. The outer diameter of the fiber-passing section 512 is greater than the outer diameter of the detection optical fiber wound on the main body section 511. The outer diameter of the connecting section 513 is greater than the outer diameter of the fiber-passing section 512. The connecting section 513 is sleeved on the second end of the positioning post 520 and fastened by at least two second fasteners 530. A fiber-passing groove 514 is opened on the outer periphery of the fiber-passing section 512 for the detection optical fiber to extend into the connecting section 513. The end face of the clamping body 410 is provided with a detection fiber inlet hole 415 in the coverage area of ​​the connecting section 513 so that the detection optical fiber extending from the connecting section 513 can pass through the detection fiber inlet hole 415 and enter the fiber coil cavity 413. Understandably, setting the outer diameter of the fiber passage segment 512 to be larger than the outer diameter of the probe fiber wound on the main body segment 511 serves two purposes: firstly, it stops the probe fiber; secondly, it facilitates the construction of the fiber passage groove 514, and the bottom of the fiber passage groove 514 can be flush with the outer wall of the main body segment 511 to avoid the need for bending the probe fiber. Setting the outer diameter of the connecting segment 513 to be larger than the outer diameter of the fiber passage segment 512 facilitates its mounting on the positioning post 520 and also facilitates the construction of a channel for the fiber passage groove 514 and the probe fiber inlet hole 415.

[0039] In one embodiment of the present invention, a fiber outlet connector 515 extends from the end face of the connecting segment 513 opposite to the fiber-passing segment 512. The inner cavity of the fiber outlet connector 515 communicates with the fiber-passing groove 514. The fiber outlet connector 515 is inserted into the detection fiber inlet hole 415, and an O-ring seal is formed between the fiber outlet connector 515 and the detection fiber inlet hole 415. The addition of the fiber outlet connector 515 serves two purposes: sealing the fiber outlet and positioning it during the installation of the detection body 510. It is understood that the connecting segment 513 may have a channel communicating with the fiber-passing groove 514, and the fiber outlet connector 515 is located at the end of the connecting segment 513 opposite to the fiber-passing segment 512.

[0040] In one embodiment of the present invention, the clamping body 410 includes a main cavity shell 411 and a sealing cover 412. The main cavity shell 411 and the cable pressing cover 420 are respectively disposed on opposite sides of the stranded cable 100 and are detachably connected by a first fastener 430. On the side of the main cavity shell 411 away from the cable pressing cover 420, a cover space and an axial stop portion 416 are sequentially provided along the length direction of the stranded cable 100. The side of the axial stop portion 416 away from the cover space is designated as belonging to the main body. The end face of the cavity shell 411 is connected to the end face of the main cavity shell 411 where the sensitive cylinder 500 and the axial stop part 416 are located. The fiber coil cavity 413 is located on the main cavity shell 411, and the sealing opening of the fiber coil cavity 413 is set on the side of the main cavity shell 411 away from the cable clamping cover 420, corresponding to the cover space. The sealing cover 412 is placed in the cover space and its end abuts against the axial stop part 416. The sealing cover 412 is detached from the main cavity shell 411 to seal the sealing opening. That is, by detaching and installing the sealing cover 412, it is convenient to carry out the inspection and maintenance of the optical fiber connection in the fiber coil cavity 413, as well as the inspection and replacement of optical devices. The addition of the axial stop part 416 can not only stop the sealing cover 412 to reduce the shear force on the sealing cover 412, but also increase the area of ​​the end face of the main cavity shell 411 for the sensitive cylinder 500 to be installed, thereby providing sufficient area for hole routing. Specifically, the sealing cover 412 has fasteners on both sides of the sealing opening near and away from the axial stop 416 for detachable connection with the main cavity shell 411.

[0041] In one embodiment of the present invention, a sealing groove is provided around the periphery of the sealing opening for accommodating the sealing ring 417. The addition of the sealing groove and the sealing ring 417 improves the sealing performance of the fiber optic cavity 413. Furthermore, the sealing ring 417 may include, but is not limited to, an O-ring.

[0042] In one embodiment of the present invention, the cable clamping cover 420 and the main body cavity shell 411 are detachably assembled to form a cable through hole 440 for the stranded cable 100 to pass through. The end face of the cable clamping cover 420 facing the sensitive cylinder 500 is assembled with the end face of the main body cavity shell 411 where the axial stop portion 416 is located to form a circular end face. That is, the end face of the entire clamping body 410 can be set as a circular end face, and the outer contour of the clamping body 410 can be set as cylindrical or approximately cylindrical to match the outer protective sleeve 200, which is a circular tube. Specifically, the cable clamping cover 420, the main body cavity shell 411, and the sealing cover 412 at the end facing away from the sensitive cylinder 500 can be considered as a cylinder divided by two parallel chordal planes, with the two chordal planes located on opposite sides of the central axis of the clamping frame 400.

[0043] In one embodiment of the present invention, the sealing cover 412 is fitted to the side of the main cavity shell 411 with the sealing opening, and the side of the sealing cover 412 opposite to the sealing opening has a mounting plane 418 extending along the length direction of the stranded cable 100. The mounting plane 418 has a connecting hole for the rod of the third fastener 450 to pass through and connect to the main cavity shell 411, and the head of the third fastener 450 is fitted to the mounting plane 418. That is, by adding the mounting plane 418, the contact area between the third fastener 450 and the main cavity shell 411 can be increased, ensuring the reliability of the connection between the third fastener 450 and the sealing cover 412 and the main cavity shell 411. Furthermore, when the main cavity shell 411 is laid flat on the side where it is attached to the cable clamping cover 420, the height of the mounting plane 418 on the sealing cover 412 is the maximum height of the sealing cover 412. The mounting plane 418 is centered in the circumferential direction of the sealing cover 412, and the height of the mounting plane 418 on the sealing cover 412 is lower than the maximum height of the axial stop 416. This ensures that the head of the third fastener 450 does not protrude from the cylindrical outer contour, so as to avoid affecting the outer diameter of the outer protective sleeve 200.

[0044] like Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the support frame assembly 300 includes a coaxial support frame 310, an eccentric support frame 320, and a dielectric filling layer 330. The outer protective sleeve 200 includes a basic segment 210 and a spacer segment 220. Both ends of the basic segment 210 are spacer segments 220. The hydrophone basic unit is disposed within the basic segment 210, and the basic segment 210 has eccentric support frames 320 clamped on the stranded cable 100 on both sides of the hydrophone basic unit. The central axis of the unit is offset towards the side where the clamping body 410 is located. The interval section 220 is provided with a coaxial support frame 310 clamped on the stranded cable 100. The central axis of the coaxial support frame 310 is collinear with the central axis of the stranded cable 100. The medium filling layer 330 is used to fill the outer protective sleeve 200, so that the basic unit section 210 is coaxial with the stranded cable 100 and the central axis of the basic unit section 210 is offset towards the side of the stranded cable 100 where the clamping body 410 is located. It should be noted that the stranded cable 100 in this invention is straight, and the inner and outer diameters of the outer protective sleeve 200 are consistent along the entire length. By setting the interval section 220 and the coaxial support frame 310, it can be ensured that the stranded cable 100 in the array except for the basic element section 210 is centered. By setting the eccentric support frame 320, both ends of the offset hydrophone basic element are provided with support frames to support the stranded cable 100 and the outer protective sleeve 200, thereby improving the reliability and strength of the array.

[0045] In one embodiment of the present invention, the support frame assembly 300 further includes an adhesive filling connector 340. The adhesive filling connector 340 has a connector through-hole for the stranded cable 100 to pass through, and one end of the adhesive filling connector 340 passes through the end of the spacer section 220, while the other end extending out of the spacer section 220 has an adhesive filling port 341 for injecting adhesive into the outer protective sleeve 200 to form a medium filling layer 330. That is, by adding the adhesive filling connector 340, on the one hand, the end of the spacer section 220 can be supported for the outer protective sleeve 200, and on the other hand, by injecting adhesive into the outer protective sleeve 200 after sealing, it is obviously beneficial to realize the adhesive filling operation. In addition, the outer side of the spacer section 220 can be fitted onto the adhesive filling connector 340 by a clamping ring.

[0046] See Figure 3 and Figure 4 In one embodiment of the present invention, two opposite end faces of the clamping body 410 are provided with transmission fiber inlet holes 419. A tube bundle docking assembly 460 is provided on the transmission fiber inlet hole 419. The tube bundle docking assembly 460 includes a hollow screw 461, a washer 462, and a gasket 463, which are sequentially fitted onto the fiber optic tube cut in the stranded cable 100. The hollow screw 461 is tightened onto the transmission fiber inlet hole 419 to allow the transmission optical fiber inside the fiber optic tube to enter the fiber coil cavity 413. That is, when the hollow screw 461 is tightened onto the transmission fiber inlet hole 419, the washer 462 and gasket 463 are pressed between the head of the hollow screw 461 and the clamping body 410, thereby providing a seal and ensuring the stability of the fiber optic tube passing through the hollow screw 461.

[0047] Please see again Figure 1 and Figure 2In one embodiment of the present invention, the stranded cable 100 contains at least two optical fiber tubes, each comprising a first optical fiber tube 101 and a second optical fiber tube 102 extending from opposite ends of the clamping body 410 into the fiber optic cavity 413. The first optical fiber tube 101 and the transmission fiber within it are firstly cut outside the first end of the clamping body 410, and secondly cut outside the second end of the clamping body 410. The transmission fiber within the first optical fiber tube 101 extends from the second end of the clamping body 410 into the fiber optic cavity 413. Similarly, the second optical fiber tube 102 and the transmission fiber within it are firstly cut outside the second end of the clamping body 410, and secondly cut outside the first end of the clamping body 410. The transmission fiber within the second optical fiber tube 102 extends from the first end of the clamping body 410 into the fiber optic cavity 413. This ensures that the transmission fibers entering the fiber optic cavity 413 have sufficient length for connection with the optical devices within the fiber optic cavity 413. Specifically, the first optical fiber tube 101 and the transmission optical fiber inside the tube can be cut off for the first time at the glue-filled connector 340 located on the outside of the first end of the clamping body 410, and the second optical fiber tube 102 and the transmission optical fiber inside the tube can be cut off for the first time at the glue-filled connector 340 located on the outside of the second end of the clamping body 410.

[0048] Furthermore, the fasteners mentioned in this invention can be threaded fasteners, pins, or rivets, etc.

[0049] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0051] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0052] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A fiber optic hydrophone array with biased hydrophone elements, characterized in that, include: Stranded cable, comprising stranded optical fiber tubes and tensile metal wires; An outer protective sleeve is fitted over the outside of the stranded cable; A support frame assembly is disposed inside the outer protective sleeve and is used to support the stranded cable; A hydrophone element is placed inside the outer protective sleeve and includes a clamping frame and a sensitive cylinder with a detection optical fiber wound around it. The clamping frame includes a clamping body and a cable clamping cover. The clamping body and the cable clamping cover are respectively located on opposite sides of the stranded cable and are detached and connected by a first fastener. The clamping body has a fiber coil cavity for the detection optical fiber and the transmission optical fiber in the optical fiber tube to extend into. The sensitive cylinder and the clamping body are located on the same side of the stranded cable and are endo-connected, so that the hydrophone element is offset on the stranded cable, and the section of stranded cable in which the hydrophone element is located is offset inside the outer protective sleeve.

2. The fiber optic hydrophone array with biased hydrophone elements according to claim 1, characterized in that, The end face of the clamping body is provided with a fastening hole. The sensitive cylinder includes a detection body and a positioning post. The first end of the positioning post is fastened through the fastening hole. The detection optical fiber is wound around the detection body and its end is sleeved on the second end of the positioning post. The detection body and the second end of the positioning post are fastened together by at least two second fasteners. The at least two second fasteners are arranged sequentially at intervals along the circumference of the detection body.

3. The fiber optic hydrophone array with biased hydrophone elements according to claim 2, characterized in that, The detection body includes a main body section, a fiber-passing section, and a connecting section arranged coaxially along the length of the stranded cable. The detection optical fiber is wound around the outer side of the main body section. The outer diameter of the fiber-passing section is larger than the outer diameter of the detection optical fiber wound on the main body section. The outer diameter of the connecting section is larger than the outer diameter of the fiber-passing section. The connecting section is sleeved on the second end of the positioning post and fastened by at least two second fasteners. The outer periphery of the fiber-passing section has a fiber-passing groove for the detection optical fiber to extend into the connecting section. The end face of the clamping body has a detection fiber inlet hole in the coverage area of ​​the connecting section, so that the detection optical fiber extending from the connecting section passes through the detection fiber inlet hole and enters the fiber coil cavity.

4. The fiber optic hydrophone array with biased hydrophone elements according to claim 3, characterized in that, The connecting section extends outward from the end face opposite to the fiber passage section and is provided with a fiber outlet connector. The inner cavity of the fiber outlet connector is connected to the fiber passage groove. The fiber outlet connector is inserted into the detection fiber inlet hole, and the fiber outlet connector and the detection fiber inlet hole are sealed by an O-ring.

5. The fiber optic hydrophone array with biased hydrophone elements according to claim 1, characterized in that, The clamping body includes a main cavity shell and a sealing cover. The main cavity shell and the cable pressing cover are respectively disposed on opposite sides of the stranded cable and are detachably connected by a first fastener. On the side of the main cavity shell away from the cable pressing cover, a cover space and an axial stop are sequentially provided along the length direction of the stranded cable. The side of the axial stop away from the cover space is set as the end face of the main cavity shell. The sensitive cylinder is connected to the end face of the main cavity shell where the axial stop is located. The fiber coil cavity is disposed on the main cavity shell, and the sealing opening of the fiber coil cavity is set on the side of the main cavity shell away from the cable pressing cover, corresponding to the cover space. The sealing cover is placed in the cover space and its end abuts against the axial stop. The sealing cover is detachably connected to the main cavity shell to seal the sealing opening.

6. The fiber optic hydrophone array with biased hydrophone elements according to claim 5, characterized in that, The periphery of the sealing opening is provided with a sealing groove for accommodating the sealing ring; And / or, the cable pressing cover and the main body cavity shell are detachably assembled to form a cable through hole for the stranded cable to pass through, and the end face of the cable pressing cover facing the sensitive cylinder is assembled with the end face of the main body cavity shell where the axial stop part is located to form a circular end face; And / or, the sealing cover is fitted to the side of the main cavity shell where the sealing opening is provided, and the side of the sealing cover away from the sealing opening is provided with an installation plane extending along the length direction of the stranded cable. The installation plane is provided with a connecting hole, the connecting hole for the rod of the third fastener to pass through and connect to the main cavity shell, and the head of the third fastener is fitted to the installation plane.

7. The fiber optic hydrophone array with hydrophone element bias according to any one of claims 1 to 6, characterized in that, The support frame assembly includes a coaxial support frame, an eccentric support frame, and a dielectric filling layer. The outer protective sleeve includes a basic segment and a spacer segment. Both ends of the basic segment are set as the spacer segment. The hydrophone basic unit is located within the basic segment, and the basic segment has an eccentric support frame clamped on the stranded cable on both sides of the hydrophone basic unit. The central axis of the eccentric support frame is offset towards the side where the clamping body is located. The spacer segment has a coaxial support frame clamped on the stranded cable. The central axis of the coaxial support frame is collinear with the central axis of the stranded cable. The dielectric filling layer is used to fill the outer protective sleeve, so that the basic segment is coaxial with the stranded cable and the central axis of the basic segment is offset towards the side of the stranded cable where the clamping body is located.

8. The fiber optic hydrophone array with biased hydrophone elements according to claim 7, characterized in that, The support frame assembly also includes a glue-filling connector, which has a connector through hole for the stranded cable to pass through, and one end of the glue-filling connector passes through the end of the interval section, and the other end extending out of the interval section has a glue-filling port, which is used to inject glue into the outer protective sleeve to form the medium filling layer.

9. The fiber optic hydrophone array with hydrophone element bias according to any one of claims 1 to 6, characterized in that, The clamping body has two opposite end faces with transmission fiber inlet holes. The transmission fiber inlet holes are provided with tube bundle docking components. The tube bundle docking components include hollow screws, washers and gaskets that are sequentially sleeved on the optical fiber tubes cut off in the stranded cable. The hollow screws are tightened and installed on the transmission fiber inlet holes so that the transmission optical fiber in the optical fiber tubes can enter the fiber coil cavity.

10. The fiber optic hydrophone array with hydrophone element bias according to any one of claims 1 to 6, characterized in that, The stranded cable contains at least two fiber optic tubes, each comprising a first fiber optic tube and a second fiber optic tube extending into the fiber coil cavity from opposite ends of the clamping body. The first fiber optic tube and the transmission fiber within it are firstly cut outside the first end of the clamping body, and then secondly cut outside the second end of the clamping body. The transmission fiber within the first fiber optic tube extends into the fiber coil cavity from the second end of the clamping body. The second fiber optic tube and the transmission fiber within it are firstly cut outside the second end of the clamping body, and then secondly cut outside the first end of the clamping body. The transmission fiber within the second fiber optic tube extends into the fiber coil cavity from the first end of the clamping body.

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