Deep-sea high hydrostatic pressure resistant ionic polymer hydrophone structure and assembly method

Abstract

The invention provides a deep-sea high hydrostatic pressure resistant ionic polymer hydrophone structure and an assembly method, and belongs to the technical field of underwater acoustic sensing, the deep-sea high hydrostatic pressure resistant ionic polymer hydrophone structure comprises an upper shell, a shielding copper net, a substrate, a circuit board, a lower shell, a dry state sensitive film, a screw, a pressing plate, a positive electrode and a negative electrode, the shielding copper net is arranged at the top of the lower shell, a dry-state sensitive film is fixed on the front surface of the substrate, a circuit board is adhered to the back surface of the substrate, the substrate is inserted into the lower shell, a cavity at the lower part of the substrate is encapsulated and cured, and after the pressure-resistant shell is packaged, water is injected into the shell of the ionic polymer hydrophone and defoaming is performed. And finally, sealing and curing the water injection hole of the lower shell by using a sealant to form the ionic membrane polymer hydrophone. According to the invention, perfect packaging, low sound wave loss and good low-frequency sensitivity of the hydrophone in a deep water condition can be ensured, and the hydrophone has important popularization and application values for the work of the hydrophone in a deep sea level.

Description

Technical Field

[0001] This invention relates to the field of underwater acoustic sensing technology, and in particular to an ion polymer hydrophone structure and assembly method that can withstand high hydrostatic pressure in deep sea. Background Technology

[0002] As a core support for deep-sea development and national defense security, underwater acoustic detection technology is facing significant challenges. With advancements in submarine vibration and noise reduction, ship stealth technology, and the expansion of the marine economy into the deep sea, the radiated noise of underwater targets has gradually decreased to low frequencies below 1000Hz, and even below the ambient marine noise. This poses a severe challenge to traditional sonar systems that rely primarily on high-frequency detection. Developing high-sensitivity, low-frequency underwater acoustic detection technology for deep seas has become a critical need. Hydrophones, as a core component of sonar systems, directly determine the accuracy and efficiency of underwater target monitoring. However, traditional hydrophone sensing materials struggle to simultaneously meet the requirements of low-frequency response sensitivity and underwater acoustic impedance matching, thus failing to satisfy current detection needs.

[0003] In recent years, electroactive polymers (especially ionic polymers) have provided a new direction for solving this problem. These new smart materials are composed of polymer networks and solvents, and contain ions that can move freely over long distances. They can not only generate significant electrical responses under external forces through deformation or changes in molecular configuration, exhibiting high sensitivity, but also have low mechanical and acoustic impedance characteristics, which are very close to the acoustic impedance of water. At the same time, they can be formed by polymer solution coating or casting without the need for high electric field polarization. The manufacturing process is simple and low-cost, showing great application potential in the field of low-frequency high-sensitivity hydrophones.

[0004] However, ionomers need to retain internal moisture to exhibit excellent underwater acoustic sensing performance and high hydrostatic pressure resistance. Currently, most related research is still in the experimental stage, and existing products mostly use manual encapsulation or traditional vulcanized rubber encapsulation processes. Manual encapsulation can easily lead to gaps between the electrodes and the ionomer, causing measurement errors, or excessive contact can cause polymer deformation due to compression, reducing sensor sensitivity and range. The high-temperature process of traditional vulcanized rubber encapsulation will destroy the internal moisture, seriously affecting its sensing performance and pressure resistance. Therefore, it is urgent to develop new hydrophone structures and encapsulation technologies that are adapted to the properties of ionomer materials to achieve high-precision, high-sensitivity, and high-stability monitoring of underwater acoustic targets, fill the gap in the research field of new underwater sensors, promote the development of underwater vehicle detection technology, and provide strong support for dual-use military and civilian applications. Summary of the Invention

[0005] The purpose of this invention is to provide an ion polymer hydrophone structure and assembly method that can withstand the high hydrostatic pressure of deep sea water, which can avoid the problems caused by manual packaging and high temperature curing, while ensuring that the hydrophone is well packaged and has good sensitivity when in deep water conditions.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An ion polymer hydrophone structure resistant to high hydrostatic pressure in deep sea includes an upper shell, a shielding copper mesh, a substrate, a circuit board, a lower shell, a dry-state sensitive membrane, screws, a pressure plate, a positive electrode, and a negative electrode. The upper shell and lower shell are bonded together to form a pressure-resistant outer shell for the ion polymer hydrophone. A water inlet / outlet hole is provided on the side wall of the lower shell. The shielding copper mesh is located on the top of the lower shell. The substrate has a hollow center and is inserted into the lower shell. A dry-state sensitive membrane with a positive electrode plated at the top and a negative electrode plated at the bottom is adhered to the front of the substrate. A circuit board is adhered to the back of the substrate. Positive electrode wires, negative electrode wires, a positive power supply wire, a negative power supply wire, and a ground wire are soldered onto the circuit board. The ground wire is in full contact with the inner wall of the lower shell. A first guide hole is provided on the substrate, through which the positive electrode wires and negative electrode wires pass. The guide hole extends to the front of the substrate. The bottom of the lower housing is provided with a second guide hole for the watertight cable to be led out. After the power positive wire, power negative wire, and ground wire are connected to the watertight cable, they are led out from the second guide hole to the output display device. The shape of the dry state sensitive film is double-sided lugs. The protruding part of the lugs is plated with a positive electrode or a negative electrode on only one side. The substrate is provided with threaded holes. The pressure plate is provided with through holes of the corresponding threaded hole size. The double-sided lugs of the dry state sensitive film, as well as the positive electrode wire and the negative electrode wire, are located under the pressure plate. The positive electrode and the negative electrode are fully contacted and fixed with the positive electrode wire and the negative electrode wire through the cooperation of screws and threaded holes. The contact surface edge of the dry state sensitive film and the substrate is sealed. After water is injected into the pressure-resistant housing of the ion polymer hydrophone, a vacuum is drawn. The water injection outlet hole on the side wall of the lower housing is sealed and cured with waterproof sealant.

[0007] Furthermore, the pressure-resistant housing of the ion polymer hydrophone has a size of 30mm-80mm, an upper housing thickness of 3mm-6mm, a lower housing height of 10-25mm, a lower housing wall thickness of 4mm-10mm, a shielding copper mesh thickness of 0.1mm-0.5mm, and a dry-state sensitive membrane thickness of 0.5mm-0.8mm.

[0008] An assembly method for an ionomer hydrophone structure resistant to high hydrostatic pressure in deep sea water includes the following steps: Step S1. Component Assembly: The substrate and circuit board are bonded back to back. Positive electrode wire, negative electrode wire, positive power supply wire, negative power supply wire, and ground wire are soldered on the circuit board. The ground wire is in full contact with the inner wall of the lower housing. The top of the dry state sensitive film with double lugs is plated with a positive electrode and the bottom is plated with a negative electrode. The protruding part of the lugs is plated with a positive electrode or a negative electrode on only one side. The substrate has a first guide hole and a threaded hole. The positive electrode wire and the negative electrode wire extend to the front of the substrate through the first guide hole on the substrate. The bottom of the lower housing has a second guide hole for the watertight cable to be led out. After the positive power supply wire, the negative power supply wire, and the ground wire are connected to the watertight cable, they are led out to the output display device through the second guide hole. The pressure plate has a through hole of the corresponding threaded hole size. The double lugs of the dry state sensitive film and the positive electrode wire and the negative electrode wire are pressed under the pressure plate. The pressure plate is tightened by screws and threaded holes to make the positive electrode and the negative electrode fully contact and fix the wires. The edge of the contact surface between the dry state sensitive film and the substrate is sealed.

[0009] Step S2. Sealing and Casting: Spray conformal coating onto the front of the circuit board, fix the substrate inside the lower housing, inject the prepared polyurethane solution into the lower housing, and after curing, the circuit board is completely sealed.

[0010] Step S3. Overall assembly: Use conductive silver paste to fix the shielding copper mesh to the top of the lower housing, and then use sealant to bond the upper and lower housings together. After curing, the pressure-resistant housing of the ion polymer hydrophone is obtained.

[0011] Step S4. Water Injection and Sealing: Inject water into the pressure-resistant housing of the ion polymer hydrophone to fully convert the dry-state sensitive membrane into the swollen-state sensitive membrane. Use vacuum negative pressure to remove air bubbles from the pressure-resistant housing of the ion polymer hydrophone. Finally, seal the water injection outlet with waterproof sealant to form the ion polymer hydrophone.

[0012] Further, in step S3, the upper shell is cast by spraying a release agent onto the upper and lower cover plates, fastening the upper and lower cover plates together and fixing them with 5-10 screws, injecting polyurethane into the interior of the upper and lower cover plates, and obtaining the upper shell after curing.

[0013] Furthermore, in step S1, the method for depositing a positive electrode on the top and a negative electrode on the bottom of the dry state sensitive film is to spray PDOT, spray silver nanowires, or chemically plate, and the thickness of the positive and negative electrodes does not exceed 0.1 mm.

[0014] Furthermore, in step S1, the edge of the contact surface between the dry sensitive film and the substrate is sealed by a method of sealing adhesive ring coating and curing.

[0015] Furthermore, in step S1, the ground wire is made in contact with the inner wall of the lower housing by screw fixing, conductive adhesive fixing, or welding fixing.

[0016] Furthermore, in step S3, the shielding copper mesh is brought into contact with the lower housing by screw fixing or conductive silver paste fixing.

[0017] Furthermore, in step S2, the polyurethane injection height is related to the substrate height, and the injection height does not exceed the upper surface of the substrate.

[0018] Furthermore, in step S2, the curing methods of the polyurethane solution include room temperature curing and heat curing.

[0019] Advantages of this invention: 1. The packaging process of the present invention fixes the dry sensitive film around the perimeter and hollows out the middle of the substrate, which not only provides space for the dry sensitive film to expand and deform, but also avoids the problem of poor sensor sensitivity caused by the dry sensitive film having small deformation due to complete fixation.

[0020] 2. The packaging process of this invention ensures that only the front of the dry-state sensitive film is in the water environment after water is injected by completely insulating and sealing the back of the dry-state sensitive film, the circuit board and the positive and negative wires, so that the positive and negative electrodes will not conduct and the circuit board will work normally, thus providing a guarantee for the long-term operation of the hydrophone in the water environment.

[0021] 3. In this invention, the dry-state sensitive membrane has a double-sided convex shape, which facilitates the connection and fixation of the positive and negative electrodes and will not cause the sensor signal to deteriorate or the measurement range to shorten due to the application of pre-tightening force during fixation.

[0022] 4. This invention uses polyurethane as the upper shell material, which has a sound transmittance close to that of water, effectively increasing the transmittance of signals in water and further improving the sensitivity of the hydrophone.

[0023] 5. The present invention injects water into the upper and lower shells, defoams and seals them, forming a water-polyurethane-water-sensitive membrane transmission process, ensuring that the signal loss is minimized in the transmission process. Attached Figure Description

[0024] Figure 1 This is an exploded view of the structural assembly of the present invention; Figure 2 This is an overall cross-sectional view of the structure of the present invention; Figure 3 This is a schematic diagram of the assembly of the double-sided lugs of the dry-state sensitive membrane with the positive and negative electrodes in this invention; Figure 4 This is an exploded view of the assembly of the substrate, the dry-state sensitive film, the screws, and the pressure plate in this invention. Figure 5 This is a schematic diagram of the upper cover plate and the lower cover plate in this invention; In the diagram: 1. Upper housing, 2. Shielding copper mesh, 3. Substrate, 4. Circuit board, 5. Lower housing, 6. Dry state sensitive membrane, 7. Screw, 8. Pressure plate, 9. Upper cover plate, 10. Lower cover plate, 11. Positive electrode, 12. Negative electrode. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0026] like Figures 1-4As shown, an ion polymer hydrophone structure resistant to high hydrostatic pressure in deep sea includes an upper shell 1, a shielding copper mesh 2, a substrate 3, a circuit board 4, a lower shell 5, a dry-state sensitive membrane 6, screws 7, a pressure plate 8, a positive electrode 11, and a negative electrode 12. The upper shell 1 and the lower shell 5 are bonded together to form a pressure-resistant outer shell for the ion polymer hydrophone. Water inlet and outlet holes are provided on the side wall of the lower shell 5. The shielding copper mesh 2 is located on the top of the lower shell 5. The substrate 3 has a hollow center and is inserted into the lower shell 5. A dry-state sensitive membrane 6 with a positive electrode 11 plated at the top and a negative electrode 12 plated at the bottom is adhered to the front of the substrate 3. The circuit board 4 is adhered to the back of the substrate 3. The circuit board 4 is soldered with a positive electrode wire, a negative electrode wire, a positive power supply wire, a negative power supply wire, and a ground wire. The ground wire is in full contact with the inner wall of the lower housing 5. The substrate 3 is provided with a first guide hole. The positive electrode wire and the negative electrode wire extend to the front of the substrate 3 through the first guide hole. The bottom of the lower housing 5 is provided with a second guide hole for the watertight cable to be led out. After the positive power supply wire, the negative power supply wire, and the ground wire are connected to the watertight cable, they are led out from the second guide hole to the output display device. The shape of the dry state sensitive film 6 is a double-sided lug. The protruding part of the lug is plated with a positive electrode 11 or a negative electrode 12 on only one side to ensure that the pre-tightening force of the pressure plate 8 does not affect the performance of the hydrophone. The substrate 3 is provided with threaded holes, and the pressure plate 8 is provided with through holes of the corresponding threaded hole size. The double lugs of the dry state sensitive membrane 6, as well as the positive electrode wire and the negative electrode wire, are located under the pressure plate 8. The positive electrode 11 and the negative electrode 12 are fully contacted and fixed with the positive electrode wire and the negative electrode wire through the cooperation of the screw 7 and the threaded hole. The contact surface edge between the dry state sensitive membrane 6 and the substrate 3 is sealed. After water is injected into the pressure-resistant shell of the ion polymer hydrophone, a vacuum is drawn. The water injection outlet hole on the side wall of the lower shell 5 is sealed and cured with waterproof sealant.

[0027] The shielding copper mesh 2 and the ground wire are both in contact with the lower housing 5, thereby forming a complete shielding layer.

[0028] In a preferred embodiment of the present invention, the pressure-resistant housing of the ion polymer hydrophone has a size of 30mm-80mm, the upper housing 1 has a thickness of 3mm-6mm, the lower housing 5 has a height of 10-25mm, the lower housing 5 has a wall thickness of 4mm-10mm, the shielding copper mesh 2 has a thickness of 0.1mm-0.5mm, and the dry-state sensitive membrane 6 has a thickness of 0.5mm-0.8mm.

[0029] An assembly method for an ionomer hydrophone structure resistant to high hydrostatic pressure in deep sea water includes the following steps: Step S1. Component Assembly: The substrate 3 and circuit board 4 are bonded back-to-back. Positive electrode wires, negative electrode wires, positive power supply wires, negative power supply wires, and a ground wire are soldered onto the circuit board 4. The ground wire is in full contact with the inner wall of the lower housing 5. A positive electrode 11 is plated on the top of the dry-state sensitive film 6 with double-sided lugs, and a negative electrode 12 is plated on the bottom. The protruding portion of the lugs is plated with either a positive electrode 11 or a negative electrode 12 on only one side. A first guide hole and a threaded hole are provided on the substrate 3. The positive electrode wires and negative electrode wires extend to the front side of the substrate 3 through the first guide hole. The lower housing... The bottom of the device is provided with a second guide hole for the watertight cable to be led out. After the power positive wire, power negative wire and ground wire are connected to the watertight cable, they are led out from the second guide hole to the output display device. The pressure plate 8 has a through hole with a corresponding thread hole size. The double lugs of the dry state sensitive film 6 and the positive electrode wire and negative electrode wire are pressed under the pressure plate 8. The pressure plate 8 is tightened by the screw 7 and the thread hole, so that the positive electrode 11 and negative electrode 12 are in full contact with the wires and are fixed, and the edge of the contact surface between the dry state sensitive film 6 and the substrate 3 is sealed.

[0030] Step S2. Sealing and Casting: Spray conformal coating on the front of the circuit board 4, fix the substrate 3 inside the lower housing 5, inject the prepared polyurethane solution into the lower housing 5, and after curing, the circuit board 4 is completely sealed.

[0031] Step S3. Overall assembly: Use conductive silver paste to fix the shielding copper mesh 2 to the top of the lower housing 5, and then use sealant to bond the upper housing 1 and the lower housing 5. After curing, the pressure-resistant housing of the ion polymer hydrophone is obtained.

[0032] Step S4. Water injection and encapsulation: Water is injected into the pressure-resistant housing of the ion polymer hydrophone to fully convert the dry-state sensitive membrane 6 into the swollen-state sensitive membrane. Air bubbles in the pressure-resistant housing of the ion polymer hydrophone are removed using vacuum negative pressure. Finally, the water injection outlet is sealed and cured with waterproof sealant to form the ion polymer hydrophone.

[0033] As a preferred embodiment of the present invention, such as Figure 5 As shown, in step S3, the upper shell 1 is cast by spraying a release agent onto the upper cover plate 9 and the lower cover plate 10, fastening the upper cover plate 9 and the lower cover plate 10 together and fixing them with 5-10 screws, injecting polyurethane into the interior of the upper cover plate 9 and the lower cover plate 10, and obtaining the upper shell 1 after curing.

[0034] In a preferred embodiment of the present invention, in step S1, the method for depositing a positive electrode 11 on the top and a negative electrode 12 on the bottom of the dry state sensitive film 6 is to spray PDOT, spray silver nanowires, or chemically plate, and the thickness of the positive electrode 11 and the negative electrode 12 does not exceed 0.1 mm.

[0035] In a preferred embodiment of the present invention, in step S1, the contact edge between the dry sensitive film 6 and the substrate 3 is sealed by a sealing adhesive ring coating and curing method to ensure that the positive and negative electrodes do not come into contact with the water medium at the same time.

[0036] In a preferred embodiment of the present invention, in step S1, the ground wire is contacted with the inner wall of the lower housing 5 by screw fixing, conductive adhesive fixing, or welding fixing.

[0037] In a preferred embodiment of the present invention, in step S3, the shielding copper mesh 2 is made to contact the lower housing 5 by screw fixing or conductive silver paste fixing.

[0038] In a preferred embodiment of the present invention, in step S2, the polyurethane injection height is related to the height of the substrate 3, and the injection height does not exceed the upper surface of the substrate 3.

[0039] In a preferred embodiment of the present invention, in step S2, the curing method of the polyurethane solution includes room temperature curing and heat curing.

[0040] Example 1: First, the upper shell 1 is cast. The upper cover plate 9 and lower cover plate 10 are then fixed with M3 screws. The upper cover plate 9 is a solid, rectangular structure with dimensions of 55mm width, 55mm length, 18mm depth, and 5mm wall thickness. It also includes a stepped limiting groove with dimensions of 57mm width, 57mm length, and 4mm depth. The lower cover plate 10 is a hollow, rectangular structure with dimensions of 67mm width, 67mm length, 23mm depth, and 5mm wall thickness. Through the interlocking of the two cover plates, a semi-open casting space with dimensions of 57mm width, 57mm length, 18mm depth, and 1mm wall thickness is naturally formed between them. After spraying a release agent into this space, the prepared polyurethane solution is poured in and cured at room temperature for 24 hours to obtain the upper shell 1.

[0041] Next, a lower shell 5 with dimensions of 55mm wide, 55mm long, 23mm deep, and 3.5mm thick is obtained by machining. Water inlet and outlet holes with a diameter of 2mm are opened on both the left and right side walls of the lower shell, and a second guide hole with a diameter of 9mm is opened at the bottom of the lower shell.

[0042] The substrate 3 has a rectangular structure with dimensions of 45mm wide, 45mm long, and 3mm deep. The front side of the substrate 3 has four M3 threaded through holes for fixing the pressure plate 8 and two first guide holes for guiding the electrode wires. The back side of the substrate 3 has four corner feet with dimensions of 5mm wide, 5mm long, and 10mm high.

[0043] The back of circuit board 4 is bonded to the back of substrate 3. After soldering the wires, the positive and negative electrode wires are extended to the front of substrate 3 through the first guide hole. The dry sensitive film 6 with plated electrodes is clamped between the two electrode wires and fixed with screws 7 and pressure plates 8. Waterproof sealant is applied in a ring to seal and cure, so that the front and back of the dry sensitive film 6 are isolated. After applying conformal adhesive to the front of circuit board 4 for preliminary sealing, substrate 3 is inserted into the lower housing 5. After ensuring that the ground wire is in full contact with the lower housing 5 and conducting, the prepared polyurethane is poured in so that the polyurethane reaches exactly the height of the substrate. It is then cured at room temperature to obtain a completely waterproof and sealed circuit board 4. A shielding copper mesh 2 with a length of 57mm, a width of 57mm, and a thickness of 0.3mm is fixed to the top of the upper housing with conductive silver paste to form an outer shell shielding layer. Then, waterproof sealant is used to attach and seal the upper housing 1 and the lower housing 5. After curing, the pressure-resistant housing of the ion polymer hydrophone is obtained. Water is injected into the pressure-resistant housing of the ion polymer hydrophone, so that the dry sensitive membrane is fully converted into a swollen sensitive membrane. Air bubbles in the housing are removed by vacuuming. Finally, the water outlet is sealed with waterproof sealant and cured to form the ion polymer hydrophone.

[0044] Example 2: First, the upper shell 1 is cast. The upper cover plate 9 and the lower cover plate 10 are then fixed with M3 screws. The upper and lower cover plates are identical in size, both being rectangular structures measuring 68mm in length, 63mm in height, and 7.5mm in width, with a hollow interior. Through the interlocking of the two cover plates, a semi-open casting space naturally forms between them, measuring 58mm in length, 58mm in width, and 5mm in thickness. After spraying a release agent into this space, the prepared polyurethane solution is poured in and cured at room temperature for 24 hours to obtain the upper shell 1.

[0045] Next, a lower housing 5 with dimensions of 64mm width, 64mm length, 26mm depth, and 8mm wall thickness is obtained by machining. A water inlet / outlet hole with a diameter of 2mm is opened on one side wall of the lower housing 5, allowing for water inlet and outlet through a single hole. A vertical threaded hole with a diameter of 3mm and a depth of 5mm is opened on the top surface of the lower housing 5. A second guide hole with a diameter of 5mm is opened at the bottom end of the lower housing 5.

[0046] The substrate 3 has a rectangular structure with dimensions of 42mm wide, 42mm long, and 4mm deep. On the front side, there are four M3 threaded through holes for fixing the pressure plate 8 and two first guide holes for guiding the electrode wires. The back side of the substrate 3 has four corner feet with dimensions of 4mm wide, 4mm long, and 10mm high.

[0047] The back of circuit board 4 is bonded to the back of substrate 3. After soldering the wires, the positive and negative electrode wires are extended to the front of substrate 3 through the guide holes. The dry-state sensitive film 6 with plated electrodes is clamped between the two electrode wires and fixed with screws 7 and pressure plates 8. Waterproof sealant is applied and sealed, and then cured to isolate the front and back of the dry-state sensitive film 6. After applying conformal adhesive to the front of circuit board 4 for initial sealing, substrate 3 is inserted into the lower housing 5. The ground wire is wrapped around the screw and screwed into the vertical threaded hole of the lower housing 5 to ensure full contact with the lower housing 5. Then, the prepared polyurethane is poured in so that the polyurethane reaches the height of the substrate and is cured at room temperature to obtain a completely waterproof and sealed circuit board 4. A shielding copper mesh 2 with a length of 58mm, a width of 58mm, and a thickness of 0.3mm is fixed to the top of the upper housing with conductive silver paste to form an outer shell shielding layer. Then, waterproof sealant is used to bond and seal the upper housing 1 and the lower housing 5. After curing, the pressure-resistant housing of the ion polymer hydrophone is obtained. Water is injected into the pressure-resistant housing of the ion polymer hydrophone, so that the dry-state sensitive membrane 6 is fully converted into the swollen-state sensitive membrane. Air bubbles in the housing are removed by vacuum negative pressure. Finally, the water injection outlet is sealed and cured with waterproof sealant to form the ion polymer hydrophone.

[0048] In summary, this invention forms a single-sided detection system by directly attaching the sensitive membrane to the substrate; by utilizing the swelling property of the membrane to form an interference fit with the reserved space for fixation, it overcomes the problem of excessive fixation causing polymer extrusion deformation, which leads to decreased sensor sensitivity and shortened measurement range; by controlling the water injection time to ensure that the membrane is completely in an aqueous environment, and by using a pressurization method to remove air bubbles in the water, it ensures that the signal from the water has minimal loss during the transmission process of water-polyurethane-water-sensitive membrane.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art can still adjust the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Therefore, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include these modifications and variations.

Claims

1. An ion polymer hydrophone structure resistant to high hydrostatic pressure in deep sea, characterized in that: The device includes an upper housing (1), a shielding copper mesh (2), a substrate (3), a circuit board (4), a lower housing (5), a dry-state sensitive membrane (6), screws (7), a pressure plate (8), a positive electrode (11), and a negative electrode (12). The upper housing (1) and the lower housing (5) are bonded together to form a pressure-resistant outer shell for an ion polymer hydrophone. A water inlet / outlet hole is provided on the side wall of the lower housing (5). The shielding copper mesh (2) is located on the top of the lower housing (5). The substrate (3) is inserted into the interior of the lower housing (5). The substrate (3) has a hollow center. A dry-state sensitive membrane (6) with a positive electrode (11) plated on the top and a negative electrode (12) plated on the bottom is pasted on the front of the substrate (3). A circuit board (4) is bonded to the back of the substrate (3). A positive electrode wire, a negative electrode wire, a positive power supply wire, a negative power supply wire, and a ground wire are soldered on the circuit board (4). The ground wire is in full contact with the inner wall of the lower housing (5). A first guide hole is provided on the substrate (3). The positive electrode wire and the negative electrode wire... The electrode wire extends to the front of the substrate (3) through the first guide hole. The bottom of the lower housing (5) is provided with a second guide hole for the watertight cable to be led out. After the power positive wire, power negative wire and ground wire are connected to the watertight cable, they are led out from the second guide hole to the output display device. The shape of the dry state sensitive film (6) is double-sided lugs. The protruding part of the lugs is plated with a positive electrode (11) or a negative electrode (12) on only one side. The substrate (3) is provided with a threaded hole. The pressure plate (8) is provided with a through hole corresponding to the size of the threaded hole. The double-sided lugs of the dry state sensitive film (6) and the positive electrode wire and negative electrode wire are placed under the pressure plate (8) and the positive electrode (11) and negative electrode (12) are fully contacted and fixed with the positive electrode wire and negative electrode wire through the cooperation of screws (7) and threaded holes. The contact surface edge of the dry state sensitive film (6) and the substrate (3) is sealed. After water is injected into the pressure-resistant housing of the ion polymer hydrophone, a vacuum is drawn. The water injection outlet hole on the side wall of the lower housing (5) is sealed and cured with waterproof sealant.

2. The ion polymer hydrophone structure resistant to high hydrostatic pressure in deep sea as described in claim 1, characterized in that: The pressure-resistant housing of the ion polymer hydrophone has a size of 30mm-80mm, the upper housing (1) has a thickness of 3mm-6mm, the lower housing (5) has a height of 10-25mm, the lower housing (5) has a wall thickness of 4mm-10mm, the shielding copper mesh (2) has a thickness of 0.1mm-0.5mm, and the dry state sensitive membrane (6) has a thickness of 0.5mm-0.8mm.

3. An assembly method for an ionomer hydrophone structure resistant to high hydrostatic pressure in deep sea, characterized in that, Includes the following steps: Step S1. Component Assembly: The substrate (3) and the circuit board (4) are bonded back to back. Positive electrode wires, negative electrode wires, positive power supply wires, negative power supply wires, and ground wires are soldered on the circuit board (4). The ground wires are in full contact with the inner wall of the lower housing (5). The top of the dry state sensitive film (6) with double lugs is plated with a positive electrode (11), and the bottom is plated with a negative electrode (12). The protruding part of the lugs is plated with a positive electrode (11) or a negative electrode (12) on only one side. A first guide hole and a threaded hole are provided on the substrate (3). The positive electrode wires and negative electrode wires are extended to the front side of the substrate (3) through the first guide hole on the substrate (3). The bottom of the housing (5) is provided with a second guide hole for the watertight cable to be led out. After the power positive wire, power negative wire and ground wire are connected to the watertight cable, they are led out from the second guide hole to the output display device. There is a through hole with a corresponding thread hole size on the pressure plate (8). The double lugs of the dry state sensitive film (6) and the positive electrode wire and negative electrode wire are pressed under the pressure plate (8). The pressure plate (8) is tightened by the screw (7) and the thread hole, so that the positive electrode (11) and negative electrode (12) are fully in contact with the wire and fixed, and the edge of the contact surface between the dry state sensitive film (6) and the substrate (3) is sealed. Step S2. Sealing and casting: Spray conformal coating on the front of the circuit board (4), fix the substrate (3) inside the lower housing (5), inject the prepared polyurethane solution into the lower housing (5), and after curing, the circuit board (4) will be completely sealed. Step S3. Overall assembly: Use conductive silver paste to fix the shielding copper mesh (2) to the top of the lower housing (5), and then use sealant to bond the upper housing (1) and the lower housing (5). After curing, the pressure-resistant housing of the ion polymer hydrophone is obtained. Step S4. Water injection and sealing: Water is injected into the pressure-resistant housing of the ion polymer hydrophone so that the dry state sensitive membrane (6) is fully converted into the swollen state sensitive membrane. Vacuum negative pressure is used to remove the air bubbles in the pressure-resistant housing of the ion polymer hydrophone. Finally, the water injection outlet is sealed and cured with waterproof sealant to form the ion polymer hydrophone.

4. The assembly method of an ionomer hydrophone structure resistant to high hydrostatic pressure in deep sea as described in claim 3, characterized in that: In step S3, the upper shell (1) is formed by casting. A release agent is sprayed on the upper cover plate (9) and the lower cover plate (10), the upper cover plate (9) and the lower cover plate (10) are fastened together and fixed with 5-10 screws, polyurethane is injected into the upper cover plate (9) and the lower cover plate (10), and the upper shell (1) is obtained after curing.

5. The assembly method of an ionomer hydrophone structure resistant to high hydrostatic pressure in deep sea as described in claim 4, characterized in that: In step S1, the method for depositing a positive electrode (11) on the top and a negative electrode (12) on the bottom of the dry state sensitive membrane (6) is to spray PDOT, spray silver nanowires or chemically plate, and the thickness of the positive electrode (11) and the negative electrode (12) does not exceed 0.1 mm.

6. The assembly method of an ionomer hydrophone structure resistant to high hydrostatic pressure in deep sea as described in claim 5, characterized in that: In step S1, the contact edge between the dry sensitive film (6) and the substrate (3) is sealed by a sealing adhesive ring coating and curing method.

7. The assembly method of an ion polymer hydrophone structure resistant to high hydrostatic pressure in deep sea as described in claim 6, characterized in that: In step S1, the ground wire is made in contact with the inner wall of the lower housing (5) by screw fixing, conductive adhesive fixing or welding fixing.

8. The assembly method of an ion polymer hydrophone structure resistant to high hydrostatic pressure in deep sea as described in claim 7, characterized in that: In step S3, the shielding copper mesh (2) is brought into contact with the lower housing (5) by screw fixing or conductive silver paste fixing.

9. The assembly method of an ionomer hydrophone structure resistant to high hydrostatic pressure in deep sea as described in claim 8, characterized in that: In step S2, the polyurethane injection height is related to the height of the substrate (3), and the injection height does not exceed the upper surface of the substrate (3).

10. The assembly method of an ionomer hydrophone structure resistant to high hydrostatic pressure in deep sea as described in claim 9, characterized in that: In step S2, the curing methods of the polyurethane solution include room temperature curing and heat curing.

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