Hydrophone device for underwater antenna

Abstract

A hydrophone device for an underwater antenna according to one embodiment of the present invention is a hydrophone device for an underwater antenna for detecting acoustic signals generated underwater, and is characterized by comprising: a housing shell having a two-stage structure in which a first shell and a second shell are connected; a piezoelectric ceramic provided by vertically penetrating the interior of the housing shell; a cylindrical compliance tube provided by vertically penetrating the interior of the housing shell and spaced apart from the outer side of the piezoelectric ceramic by a predetermined distance; and a flange provided to face the upper and lower ends of the housing shell and provided to fix the piezoelectric ceramic and the compliance tube.

Description

Technology Field

[0001] The present invention relates to a hydrophone device for an underwater antenna, and in particular, to a hydrophone device for an underwater antenna that can widen the reception bandwidth by reducing the amplitude of vibration generation by arranging a cylindrical compliance tube to be fixed to a ring and a flange. Background Technology

[0003] Acoustic transducers that transmit and receive sound waves underwater have been developed for submarine detection. These underwater acoustic transducers can be broadly classified into two types: the Tonpilz type, which is installed on the surface of a platform that supports reaction forces and primarily functions as an underwater sound transmitter and receiver, and the flextensional type, which operates independently while submerged. Because Tonpilz transducers utilize vibrations in the thickness direction, they are easy to manufacture and adapt to array systems, and are primarily used as high-output underwater acoustic transducers in the tens of kHz band.

[0004] Flextensional transducers are mainly used as high-power underwater acoustic transducers in the low-frequency range of 3 kHz or less because they can obtain a large volume displacement amplitude while significantly reducing volume and weight in the low-frequency range.

[0005] In addition, Flextensional transducers have the advantage of generating amplitude and sound pressure several times greater than conventional Tonpilz transducers in terms of performance. Furthermore, due to their structural characteristics, they have been proven to have excellent stability and superior durability, making them known to be the most suitable for applications requiring high output over long periods.

[0006] These flextensional transducers can be divided into approximately seven types (Class I to Class VII) depending on the shape of the shell used, and can be broadly classified into those using convex shells and those using concave shells.

[0007] For example, a Class III flextensional transducer is structured by joining two shells of a Class I flextensional transducer, and is composed of a simple form consisting only of a piezoelectric ceramic, a shell, and a flange.

[0008] When such a Class III flextensional transducer is used for transmission, it has advantages such as high sensitivity in the low-frequency range and wideband transmission frequency characteristics.

[0009] Therefore, when using a Class III flextensional transducer as a hydrophone, it has the advantage of having decent sensitivity, but has the disadvantage of having a narrow low-frequency reception bandwidth.

[0010] Due to the characteristics described above, Class III flextensional transducers developed to date are mostly used as transmitting projectors.

[0011] However, current Class III flextensional transducers have a problem in that they are difficult to use as receiving hydrophones because the receiving frequency bandwidth is narrow at low frequencies. The problem to be solved

[0013] To solve the aforementioned problem, a hydrophone device for an underwater antenna is provided that can widen the reception bandwidth by reducing the amplitude of vibration generation by arranging a cylindrical compliance tube to be fixed to a ring and a flange.

[0014] However, the technical problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems will be clearly understood by those skilled in the art from the description of the invention below. means of solving the problem

[0016] A hydrophone device for an underwater antenna according to a first embodiment of the present invention is a hydrophone device for an underwater antenna for detecting acoustic signals generated underwater, and is characterized by comprising: a housing shell having a two-stage structure in which a first shell and a second shell are connected; a piezoelectric ceramic provided by vertically penetrating the interior of the housing shell; a cylindrical compliance tube provided by vertically penetrating the interior of the housing shell and spaced apart from the outer side of the piezoelectric ceramic by a predetermined distance; and a flange provided to face the upper and lower ends of the housing shell and provided to fix the piezoelectric ceramic and the compliance tube.

[0017] Here, the feature is that it further includes a ring connecting the first shell and the second shell of the housing shell.

[0018] Here, in particular, the compliance tube is characterized by being formed of a metal material having a rigidity greater than that of aluminum.

[0019] Here, the feature is particularly in that the thickness of the compliance tube is adjusted to determine a preset reception bandwidth.

[0020] Here, in particular, the compliance tube is characterized by determining a preset reception bandwidth according to a fixed position by a flange or ring.

[0021] Here, the feature is that a preset reception bandwidth is determined in correspondence with the separation distance between the compliance tube and the piezoelectric ceramic.

[0022] Here, the feature is that it further includes a coating layer formed of a rubber material on the outer surface of the housing shell, in particular.

[0023] Here, in particular, the flange is characterized by being structured to be inserted into the top and bottom of the housing shell to secure the piezoelectric ceramic and the compliance tube.

[0024] In addition, the hydrophone device for an underwater antenna according to the second embodiment of the present invention is a hydrophone device for an underwater antenna for detecting acoustic signals generated underwater, and is characterized by comprising: a housing shell having a single structure; a piezoelectric ceramic provided by vertically penetrating the interior of the housing shell; a cylindrical compliance tube provided by vertically penetrating the interior of the housing shell and spaced apart from the outer side of the piezoelectric ceramic by a predetermined distance; and a flange provided to face the upper and lower ends of the housing shell and provided to fix the piezoelectric ceramic and the compliance tube.

[0025] Here, in particular, the compliance tube is characterized by being formed of a metal material having a rigidity greater than that of aluminum.

[0026] Here, the feature is particularly in that the thickness of the compliance tube is adjusted to determine a preset reception bandwidth.

[0027] Here, in particular, the compliance tube is characterized by determining a preset reception bandwidth according to a fixed position by a flange or ring.

[0028] Here, the feature is that a preset reception bandwidth is determined in correspondence with the separation distance between the compliance tube and the piezoelectric ceramic.

[0029] Here, the feature is that it further includes a coating layer formed of a rubber material on the outer surface of the housing shell, in particular.

[0030] Here, in particular, the flange is characterized by being structured to be inserted into the top and bottom of the housing shell to secure the piezoelectric ceramic and the compliance tube. Effects of the invention

[0032] According to one embodiment of the present invention described above, the receiving bandwidth can be widened by reducing the amplitude of vibration generation by arranging a cylindrical compliance tube to be fixed to a ring and a flange.

[0033] In addition, the reception bandwidth can be increased depending on variables such as the thickness, material, or fixed position of the compliance tube.

[0034] However, the effects obtainable through the present invention are not limited to those described above, and other unmentioned technical effects will be clearly understood by those skilled in the art from the description of the invention below. Brief explanation of the drawing

[0036] FIG. 1 is a perspective view schematically illustrating the configuration of a hydrophone device for an underwater antenna according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view schematically illustrating the configuration of a hydrophone device for an underwater antenna according to a first embodiment of the present invention. FIG. 3 is a drawing illustrating the structure of the compliance tube of the present invention. FIG. 4 is a diagram showing an example of the level difference between the peak and the valley of the RVS spectrum of the present invention. FIG. 5 is a diagram showing an example of the change in receiving bandwidth with respect to the thickness of the compliance tube of the present invention. FIG. 6 is a diagram showing an example of how the RVS spectrum changes according to the thickness of the compliance tube of the present invention. FIG. 7 is a diagram showing an example of how the RVS spectrum varies depending on the material of the compliance tube of the present invention. FIG. 8 is a diagram showing an example in which the RVS spectrum changes according to the fixed position of the compliance tube of the present invention. FIG. 9 is a schematic diagram illustrating the configuration of a hydrophone device for an underwater antenna according to a second embodiment of the present invention. Specific details for implementing the invention

[0037] The present invention is susceptible to various modifications and may have various embodiments, and specific embodiments will be described in detail with reference to the drawings. However, this is not intended to limit the invention to specific embodiments, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention. Similar reference numerals have been used for similar components in the description of each drawing.

[0038] Terms such as first, second, A, B, etc., may be used to describe various components, but said components shall not be limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component. The term "and / or" includes a combination of multiple related description items or any of the multiple related description items.

[0039] The terms used in this application are used merely to describe specific embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, terms such as "comprising" or "having" are intended to indicate the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0040] Throughout the specification and claims, when a part is described as including a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0042] FIG. 1 is a perspective view schematically illustrating the configuration of a hydrophone device for an underwater antenna according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view schematically illustrating the configuration of a hydrophone device for an underwater antenna according to a first embodiment of the present invention, FIG. 3 is a diagram illustrating the structure of a compliance tube of the present invention, FIG. 4 is a diagram showing an example of a level difference between a peak and a valley of the RVS spectrum of the present invention, FIG. 5 is a diagram showing an example of a change in reception bandwidth according to the thickness of the compliance tube of the present invention, FIG. 6 is a diagram showing an example of how the RVS spectrum changes according to the thickness of the compliance tube of the present invention, FIG. 7 is a diagram showing an example of how the RVS spectrum changes according to the material of the compliance tube of the present invention, and FIG. 8 is a diagram showing an example of how the RVS spectrum changes according to the fixed position of the compliance tube of the present invention.

[0044] The hydrophone device (100) for an underwater antenna according to the first embodiment of the present invention is a hydrophone device applied to an underwater antenna (SONAR) for the purpose of detecting acoustic signals generated underwater and performing tasks such as detection, location estimation, tracking, and identification of a target, and is a device that converts sound waves incident from an external sound source into electrical signals and transmits the converted electrical signals to a signal processing device, etc.

[0045] As illustrated in FIGS. 1 and 2, a hydrophone device (100) for an underwater antenna comprises a piezoelectric ceramic (110), a flange (120), a compliance tube (130), a housing shell (140), a coating layer (150), and a ring (160). Here, the hydrophone device (100) for an underwater antenna is described as having the configuration of a Class III flextensional hydrophone device as an example.

[0047] The piezoelectric ceramic (110) is provided by vertically penetrating the interior of the housing shell (140).

[0048] More specifically, the piezoelectric ceramic (110) of the flextensional hydrophone used in an underwater environment can be formed into a cylindrical piezoelectric ceramic to be resistant to tensile force generated by hydrostatic pressure.

[0049] These cylindrical piezoelectric ceramics (110) can be formed from PZT-based materials, and the ceramic electrodes can be formed by plating metal electrodes (usually nickel, silver, gold, etc.) on the inner and outer walls, and can be configured to allow stress application in the radial, axial, and tangential directions.

[0051] A flange (120) is positioned to face the top and bottom of a housing shell (140) to secure the piezoelectric ceramic (110) and the compliance tube (130). Here, the flange (120) is provided in a structure inserted into the top and bottom of the housing shell (140) to secure the piezoelectric ceramic (110) and the compliance tube (130). For example, the flange (120) can be secured to the housing shell (140) by bolting or welding, and can be formed considering material stiffness and thickness optimization so that the flange (120) absorbs vibration transmission or, conversely, does not change the resonance frequency.

[0052] Additionally, the flange (120) is positioned to face the top and bottom of the housing shell to serve as a mechanical sealing, structural support, acoustic impedance matching, and cable and connector support.

[0053] For example, mechanical sealing protects the piezoelectric ceramic inside the cell from external environments such as moisture, contamination, salt, and fine particles, and enables the internal space to be completely sealed even in a high-pressure underwater environment. Structural support provides stable support without interfering with the micro-movements that occur when the piezoelectric ceramic (110) vibrates, and enables the rigidity of the entire structure to withstand external pressure loads. Acoustic impedance matching reduces reflections during acoustic propagation by adjusting the shape and material of the flange and supports efficient energy transfer. Cable and connector support secures cables and connectors for electrical signal transmission and enables electrical insulation and waterproofing.

[0054] In addition, the receiving performance of a hydrophone, for example applied to Class III, can be improved by designing a structure in which a flange (120) is inserted inside a housing shell (140). At this time, the connection between the housing shell (140) and the flange (120) is extended from the inside of the flange to the outside, thereby effectively increasing the surface area of ​​the housing shell (140) without changing the overall length of the hydrophone, so that the receiving function of Class III and sensitivity can be improved.

[0055] The flange (120) can be manufactured using one or more materials such as stainless steel (SUS316L), titanium (Ti-6Al-4V), aluminum alloy (Al7075), polymer materials (PEEK, PTFE), epoxy, polyurethane, etc., to withstand underwater pressure, corrosion, and mechanical loads.

[0057] As illustrated in FIG. 3, the compliance tube (130) may be configured as a cylindrical tube that is vertically penetrated through the interior of the housing shell (140) and spaced apart from the outer side of the piezoelectric ceramic (110) by a predetermined distance. At this time, the compliance tube (130) can increase the rigidity of the hydrophone by being fixed by the flange (120) and the ring (160) after being inserted into the interior of the housing shell (140). Here, it is preferable that the compliance tube (130) be formed from a metal material having a rigidity greater than that of aluminum. For example, it may be formed from a metal material such as stainless steel (SUS316L), titanium (Ti-6Al-4V), or aluminum alloy (Al7075), and may be formed from the same metal material as the flange (120) and the housing shell (140).

[0058] As illustrated in FIG. 4, the compliance tube (130) can reduce the amplitude of higher-order vibration modes occurring in the housing shell (140) and flange (120) as the stiffness increases, thereby reducing the level difference between the peak and valley of the RVS (Receiving Voltage Response) spectrum. That is, by reducing the difference between the peak RVS level and the valley RVS level to within 3 dB, the overall receiving bandwidth can be widened.

[0059] Additionally, as illustrated in FIGS. 5 and 6, the compliance tube (130) can determine a preset reception bandwidth by adjusting the thickness of the metal material. That is, by adjusting the thickness of the compliance tube (130), a broadband reception effect for the desired reception bandwidth can be obtained. For example, it can be seen that the RVS spectrum changes depending on the thickness of the compliance tube (130) of 2.5 mm, 3.5 mm, and 4.5 mm.

[0060] In addition, as shown in FIG. 7, in addition to the thickness of the compliance tube (130), depending on the material of the compliance tube (130), 2 nd Reduce the peak RVS level or 2 nd The valley RVS level can be increased. For example, it can be observed that the RVS spectrum varies depending on the metal material, such as stainless steel and aluminum.

[0061] Additionally, as illustrated in FIG. 8, the compliance tube (130) can determine a preset receiving bandwidth according to a fixed position by a flange or ring. That is, in addition to the thickness of the compliance tube (130), by changing the fixed position of the compliance tube (130), 2 nd Reduce the peak RVS level or 2 ndThe valley RVS level can be increased. For example, it can be seen that the RVS spectrum changes depending on whether the compliance tube (130) is fixed with a flange and a ring, the compliance tube (130) is fixed only with a flange, or the compliance tube (130) is fixed only with a ring.

[0062] In addition, the receiving bandwidth may be adjusted in correspondence with the distance between the compliance tube (130) and the piezoelectric ceramic (110).

[0063] Therefore, by combining variables such as the thickness, material, and fixed position of the compliance tube (130), the level difference between the peak and the valley can be adjusted as desired, thereby increasing the receiving bandwidth. This can be seen to have a much wider low-frequency receiving bandwidth than when using a Class III flextensional transducer as a hydrophone.

[0065] The housing shell (140) is formed as a two-stage structure in which a first shell and a second shell are connected in a Class III flextensional hydrophone. Here, the first shell may be an upper shell, and the second shell may be a lower shell. Holes capable of penetrating the piezoelectric ceramic (110) are formed in the upper and lower parts of the housing shell (140), and the shell may be formed mainly of stainless steel. At this time, since forming the shell with stainless steel is difficult, it may be formed by dividing it into several parts.

[0066] More specifically, the housing shell (140) can be formed as a perfect sphere or ellipsoid, so that vibrations can be transmitted in all directions and a stable frequency can be generated. In addition, since the housing shell (140) is manufactured in two parts, manufacturing is easy and the unit cost can be lowered, and the vibration efficiency of the piezoelectric ceramic can be maximized by simple joining methods such as screw joining.

[0068] The coating layer (150) is formed of a rubber material on the outer surface of the housing shell (140).

[0069] More specifically, the coating layer (150) may be formed from a material such as silicone rubber or EPDM rubber, which has excellent flexibility, heat resistance, and anti-fouling properties, but is not limited thereto.

[0070] The coating layer (150) performs the following functions: improving corrosion resistance to prevent corrosion caused by seawater (salt, microorganisms), anti-fouling, mechanical protection to protect the shell from impact, friction, and scratching, acoustic transmission control to reduce reflection and prevent energy loss by adjusting acoustic impedance, electrical insulation to block underwater electrical noise and strengthen insulation, and noise reduction to reduce turbulent noise and cavitation noise.

[0072] The ring (160) connects the first shell and the second shell of the housing shell (140) and secures the compliance tube (130). Here, the ring (160) is inserted between the first shell, the upper shell, and the second shell, the lower shell, and the two shells can be mechanically secured by being compressed against each other. For example, the upper shell and the lower shell can be compressed by methods such as bolt fastening, welding, or flange fixing. Additionally, the ring (160) can be secured by being in close contact with the middle position of the compliance tube (130). That is, the ring (160) can secure the compliance tube (130) by connecting the first shell and the second shell.

[0074] According to the present invention described above, the receiving bandwidth can be expanded by placing a compliance tube inside a Class III flextensional hydrophone and fixing it to a flange and a ring.

[0076] FIG. 9 is a schematic diagram illustrating the configuration of a hydrophone device for an underwater antenna according to a second embodiment of the present invention.

[0077] As illustrated in FIG. 9, a hydrophone device for an underwater antenna according to a second embodiment of the present invention is a hydrophone device (200) for an underwater antenna for detecting acoustic signals generated underwater, comprising a piezoelectric ceramic (210), a flange (220), a compliance tube (230), a housing shell (240), and a coating layer (250). Here, the hydrophone device (200) for an underwater antenna is described as an example of the configuration of a Class I flextensional hydrophone device. Furthermore, a detailed description of the second embodiment of FIG. 9 is omitted with reference to the redundant description of the first embodiment described above.

[0078] The piezoelectric ceramic (210) is provided by vertically penetrating the interior of the housing shell (240).

[0079] A flange (220) is positioned to face the top and bottom of a housing shell (240) to secure the piezoelectric ceramic (210) and the compliance tube (230). Here, the flange (220) is provided in a structure inserted into the top and bottom of the housing shell (240) to secure the piezoelectric ceramic (210) and the compliance tube (230). For example, the flange (220) can be secured to the housing shell (240) by bolting or welding, and can be formed considering material stiffness and thickness optimization so that the flange (220) absorbs vibration transmission or, conversely, does not change the resonance frequency.

[0080] The compliance tube (230) may be configured as a cylindrical tube that is vertically penetrated through the interior of the housing shell (240) and spaced apart from the outer side of the piezoelectric ceramic (210) by a predetermined distance. At this time, the compliance tube (230) can be increased by being fixed by the flange (220) after being inserted into the interior of the housing shell (240).

[0081] Here, the compliance tube (230) can increase the receiving bandwidth by adjusting the level difference between the peak and the valley as desired by combining variables such as thickness, material, and fixed position. This allows for a much wider low-frequency receiving bandwidth than when using a Class I flextensional transducer as a hydrophone.

[0082] The housing shell (240) can be formed as a single ellipsoidal structure, so that vibrations can be transmitted in all directions and a stable frequency can be generated.

[0083] The coating layer (250) is formed of a rubber material on the outer surface of the housing shell (240).

[0084] More specifically, the coating layer (250) may be formed from a material such as silicone rubber or EPDM rubber, which has excellent flexibility, heat resistance, and anti-fouling properties, but is not limited thereto.

[0086] Meanwhile, although the hydrophone device of the present invention has been described in relation to specific embodiments, some or all of its components or operations are not limited thereto and can be applied to various classes according to the shape of the shell.

[0088] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will understand that other specific forms can be easily modified without altering the technical spirit or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single unit may be implemented in a distributed manner, and components described as distributed may likewise be implemented in a combined form.

[0089] The scope of the present invention is defined by the claims set forth below rather than by the detailed description above, and all modifications or variations derived from the meaning and scope of the claims and equivalent concepts thereof should be interpreted as being included within the scope of the present invention. Explanation of the symbols

[0091] 110, 210: Piezoelectric ceramics 120, 220: Flange 130, 230 : Compliance Tube 140, 240 : Housing shell 150, 250: Coating layer 160: Ring

Claims

Claim 1 A hydrophone device for an underwater antenna for detecting acoustic signals generated underwater, comprising: a housing shell having a two-stage structure in which a first shell and a second shell are connected; a piezoelectric ceramic provided by vertically penetrating the interior of the housing shell; a cylindrical compliance tube provided by vertically penetrating the interior of the housing shell and spaced apart from the outer side of the piezoelectric ceramic by a predetermined distance; and a flange provided to face the upper and lower ends of the housing shell and provided to fix the piezoelectric ceramic and the compliance tube. Claim 2 A hydrophone device for an underwater antenna according to claim 1, further comprising a ring connecting the first shell and the second shell of the housing shell. Claim 3 A hydrophone device for an underwater antenna according to claim 1, characterized in that the compliance tube is formed of a metal material having a rigidity greater than that of aluminum. Claim 4 A hydrophone device for an underwater antenna according to claim 1, characterized by determining a preset reception bandwidth by adjusting the thickness of the compliance tube. Claim 5 A hydrophone device for an underwater antenna according to claim 1, characterized in that the compliance tube determines a preset receiving bandwidth according to a fixed position by a flange or ring. Claim 6 A hydrophone device for an underwater antenna according to claim 1, characterized by determining a preset reception bandwidth corresponding to the separation distance between the compliance tube and the piezoelectric ceramic. Claim 7 A hydrophone device for an underwater antenna according to claim 1, further comprising a coating layer formed of a rubber material on the outer surface of the housing shell. Claim 8 A hydrophone device for an underwater antenna according to claim 1, characterized in that the flange is provided in a structure inserted into the upper and lower ends of the housing shell to fix the piezoelectric ceramic and the compliance tube. Claim 9 A hydrophone device for an underwater antenna for detecting acoustic signals generated underwater, comprising: a housing shell having a single structure; a piezoelectric ceramic provided by vertically penetrating the interior of the housing shell; a cylindrical compliance tube provided by vertically penetrating the interior of the housing shell and spaced apart from the outer side of the piezoelectric ceramic by a predetermined distance; and a flange provided to face the upper and lower ends of the housing shell and provided to fix the piezoelectric ceramic and the compliance tube. Claim 10 A hydrophone device for an underwater antenna according to claim 9, characterized in that the compliance tube is formed of a metal material having a rigidity greater than that of aluminum. Claim 11 A hydrophone device for an underwater antenna according to claim 9, characterized by determining a preset reception bandwidth by adjusting the thickness of the compliance tube. Claim 12 A hydrophone device for an underwater antenna according to claim 9, characterized in that the compliance tube determines a preset receiving bandwidth according to a fixed position by a flange or ring. Claim 13 A hydrophone device for an underwater antenna according to claim 9, characterized by determining a preset reception bandwidth corresponding to the separation distance between the compliance tube and the piezoelectric ceramic. Claim 14 A hydrophone device for an underwater antenna according to claim 9, further comprising a coating layer formed of a rubber material on the outer surface of the housing shell. Claim 15 A hydrophone device for an underwater antenna according to claim 9, characterized in that the flange is provided in a structure inserted into the upper and lower ends of the housing shell to secure the piezoelectric ceramic and the compliance tube.

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