Low acceleration response hydrophone

Abstract

The invention discloses a low-acceleration response hydrophone, and relates to the technical field of underwater sound receiving transducers. The invention aims to solve the problem that the vibration interference environment in the ocean affects the acoustic performance of underwater equipment. According to the low-acceleration response hydrophone provided by the invention, two suspension lugs are respectively fixed at two ends of a hydrophone main body, and two damper springs are respectively and elastically connected with the two suspension lugs; the S-shaped vibration reduction structure is of a circular-ring-shaped sheet structure, the radius axial section of the circular-ring-shaped sheet structure is S-shaped, the spring installation positioning ring and the hydrophone installation positioning ring are both circular-ring-shaped and coaxially fixed to an outer ring and an inner ring of the S-shaped vibration reduction structure in a sleeving mode respectively, and a plurality of flexible holes are evenly formed in the ring face of the S-shaped vibration reduction structure in the circumferential direction. The plurality of flexible holes are close to the outer ring of the S-shaped vibration reduction structure, and the S-shaped vibration reduction structure, the spring installation positioning ring and the hydrophone installation positioning ring are all made of rubber materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of underwater acoustic receiving transducers, and particularly relates to an elastic connection structure of a hydrophone. Background Art

[0002] In recent years, with the rapid development of marine equipment, in the fields of marine environmental monitoring, military defense, and industrial equipment, an increasingly complex vibration interference environment is closely related to low-acceleration-response hydrophones. The core requirement is to improve the purity and reliability of acoustic signal acquisition. Ocean Bottom Seismographs (OBS) and resource exploration equipment are deployed in high-turbulence areas for a long time and need to resist random vibrations caused by ocean current impacts and seabed geological activities. By using low-acceleration-response hydrophones, while maintaining high sound pressure sensitivity, the contamination of acceleration noise on low-frequency seismic wave signals can be suppressed. The propulsion systems (such as motors and propellers) of Unmanned Underwater Vehicles (UUVs) and the manipulations of underwater robot arms will generate low-frequency vibrations (10 Hz - 500 Hz). Traditional hydrophones are easily interfered by their acceleration noise, resulting in misjudgment of navigation and obstacle avoidance sonars or a decline in target recognition ability. Low-acceleration-response hydrophones can significantly improve the accuracy of autonomous operations. The vibrations of ship engines and wave slapping are conducted to the acoustic array through tow cables, forming periodic acceleration interference, which easily masks the low-frequency characteristic signals of underwater targets. Selecting low-acceleration-response hydrophones can improve the long-distance target detection ability. The underwater acoustic communication system is sensitive to the multipath effect of the channel, and acceleration noise will exacerbate the inter-symbol interference. Using low-acceleration-response hydrophones can improve the communication bandwidth and bit error rate performance of underwater Internet of Things nodes.

[0003] The research and development of low-acceleration-response hydrophones is not only a breakthrough in sensor technology but also a key node in the collaborative innovation of multiple fields such as ocean development, national defense security, and ecological protection. Its application scenarios are continuously expanding with the advancement of national strategies such as deep-sea exploration and smart ocean. Summary of the Invention

[0004] The present invention is to solve the problem that the vibration interference environment in the ocean affects the acoustic performance of underwater equipment, and now provides a low-acceleration-response hydrophone.

[0005] The low-acceleration-response hydrophone includes: a hydrophone main body 1-1, two suspension ears, and two damping springs 2-1. The two suspension ears are respectively fixed at both ends of the hydrophone main body 1-1, and the two damping springs 2-1 are respectively elastically connected to the two suspension ears;

[0006] The damping spring 2-1 includes: an S-shaped damping structure 2-3, a spring mounting positioning ring 2-4, and a hydrophone mounting positioning ring 2-5. The S-shaped damping structure 2-3 is a circular thin sheet structure, and the radius axial section of the circular thin sheet structure is S-shaped. The spring mounting positioning ring 2-4 and the hydrophone mounting positioning ring 2-5 are both circular rings and are respectively coaxially sleeved and fixed on the outer ring and the inner ring of the S-shaped damping structure 2-3. A plurality of flexible holes 2-2 are evenly arranged along the circumferential direction on the ring surface of the S-shaped damping structure 2-3. The plurality of flexible holes 2-2 are all close to the outer ring of the S-shaped damping structure 2-3. The S-shaped damping structure 2-3, the spring mounting positioning ring 2-4, and the hydrophone mounting positioning ring 2-5 are all made of rubber material.

[0007] Further, the above-mentioned suspension ear includes three cylinders with different diameters arranged coaxially in a straight line, and the cylinder in the middle has the smallest diameter; the hydrophone mounting positioning ring 2-5 is coaxially sleeved outside the cylinder in the middle.

[0008] Further, the above-mentioned low-acceleration response hydrophone further includes: a support ring 3-1 and a pressing ring 4-1;

[0009] The support ring 3-1 and the pressing ring 4-1 are ring structures with the same structure. A groove is provided on one side of the ring structure. The grooves of the support ring 3-1 and the pressing ring 4-1 face each other and can clamp the spring mounting positioning ring 2-4 therein.

[0010] Further, two support ring locking structures 3-2 are provided on the outer ring of the support ring 3-1. The two support ring locking structures 3-2 are respectively located at both ends of a diameter. Through holes are provided on the support ring locking structures 3-2;

[0011] Two pressing ring locking structures 4-2 are provided on the pressing ring 4-1. The two pressing ring locking structures 4-2 are respectively located at both ends of a diameter. Threaded holes are provided on the pressing ring locking structures 4-2;

[0012] When the two support ring locking structures 3-2 and the two pressing ring locking structures 4-2 coincide respectively, the through holes and the threaded holes can coincide with each other and are fixed to each other by a locking nut 5.

[0013] Further, the above-mentioned low-acceleration response hydrophone further includes: a support ring base 3-3;

[0014] The support ring base 3-3 is fixedly connected to the outer ring of the support ring 3-1. Two base mounting holes 3-4 are opened on the support ring base 3-3.

[0015] The beneficial effects of the low-acceleration response hydrophone of the present invention are as follows:

[0016] 1. The present invention adopts the means of combining the design of a low-acceleration hydrophone with rubber spring suspension and vibration damping, which reduces the acceleration response of the hydrophone by two-pronged approach.

[0017] 2. An annular S-section flexible rubber is used as the spring, which is equivalent to suspending with infinitely many micro-springs in the circumferential direction. It can bear the inertial forces generated radially and axially by the hydrophone, thereby achieving the effect of reducing the acceleration response of the hydrophone. Compared with the metal spring suspension, the installation is more convenient, and the cumbersome process of metal spring suspension can be omitted; the volume structure is more compact, and the installation size is effectively reduced without sacrificing performance; compared with the metal spring, it has the characteristic of being resistant to seawater corrosion.

[0018] In summary, the low-acceleration response hydrophone described in the present invention has reliable and stable performance, is maintenance-free, and is suitable for long-term service. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic structural diagram of the low-acceleration response hydrophone;

[0020] Figure 2 is a three-dimensional schematic diagram of the vibration damping spring;

[0021] Figure 3 is a planar schematic diagram of the vibration damping spring;

[0022] Figure 4 is the front view of the overall assembly of the low-acceleration response hydrophone;

[0023] Figure 5 is the left view of the overall assembly of the low-acceleration response hydrophone;

[0024] Figure 6 is the orthographic isometric view of the overall assembly of the low-acceleration response hydrophone;

[0025] Hydrophone body 1-1, cable 1-2, free-end suspension ear 1-3, cable-end suspension ear 1-4, vibration damping spring 2-1, flexible hole 2-2, S-shaped vibration damping structure 2-3, spring installation positioning ring 2-4, hydrophone installation positioning ring 2-5, support ring 3-1, support ring locking structure 3-2, support ring base 3-3, base installation hole 3-4, pressure ring 4-1, pressure ring locking structure 4-2, locking nut 5. DETAILED DESCRIPTION OF THE INVENTION

[0026] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other.

[0027] Refer to Figures 1 to 5 Specifically describing this embodiment, the low-acceleration-response hydrophone described in this embodiment includes: a hydrophone main body 1-1, a cable 1-2, a free-end suspension ear 1-3, a cable-end suspension ear 1-4, a damping spring 2-1, a flexible hole 2-2, an S-shaped damping structure 2-3, a spring installation positioning ring 2-4, a hydrophone installation positioning ring 2-5, a support ring 3-1, a support ring locking structure 3-2, a support ring base 3-3, a base installation hole 3-4, a compression ring 4-1, a compression ring locking structure 4-2, and a locking nut 5.

[0028] Inside the hydrophone main body 1-1, an air-backed piezoelectric ceramic circular tube is used as the sensitive element of the sound pressure hydrophone. Considering the working depth requirements of the hydrophone, the radius and wall thickness of the circular tube are reasonably selected. For the two side end caps, high-strength lightweight materials such as fiberglass plates and carbon fiber plates are selected under the condition of meeting the pressure resistance requirements. In this embodiment, a piezoelectric circular tube is selected as the hydrophone sensitive element, which can effectively suppress the radial acceleration response; the selection of lightweight end caps can effectively reduce the axial acceleration response of the hydrophone itself. The outside of the hydrophone main body 1-1 is coated with a polyurethane watertight layer, which plays the role of sound transmission and waterproofing. The cable 1-2 is led out from one end of the hydrophone main body 1-1 and is used to transmit the electrical signals generated by the sensitive elements inside the hydrophone main body 1-1. The cable 1-2 is a lightweight polyurethane outer sheath cable, which can reduce the influence of cable inertia on the acceleration response of the hydrophone. The free-end suspension ear 1-3 is composed of three cylinders with different diameters in a stepped shape. From right to left, they are the internal limit platform, the middle positioning platform, and the external limit platform, and the diameter of the cylinder of the middle positioning platform is the smallest. The free-end suspension ear 1-3 is arranged on the side of the hydrophone main body 1-1 without the cable. The cable-end suspension ear 1-4 is composed of three cylinders with different diameters in a stepped shape. From left to right, they are the internal limit platform, the middle positioning platform, and the external limit platform, and the diameter of the cylinder of the middle positioning platform is the smallest and larger than the cable diameter. The cable-end suspension ear 1-4 is arranged at the root position of the cable 1-2. The cable-end suspension ear 1-4 and the free-end suspension ear 1-3 are used to hang and fix the hydrophone main body 1-1. The materials of the cable-end suspension ear 1-4 and the free-end suspension ear 1-3 are both elastic polyurethane materials, which can effectively reduce the acceleration response in the frequency band above 2 kHz.

[0029] The function of the vibration damping spring 2-1 is to achieve the elastic suspension of the hydrophone body 1-1. The main body of the vibration damping spring 2-1 is made of circular elastic rubber material. The spring installation positioning ring 2-4 is a rubber ring with a rectangular cross-section located on the outer ring of the vibration damping spring 2-1, which is used to achieve the structural positioning and installation of the vibration damping spring 2-1. The hydrophone installation positioning ring 2-5 is located on the inner ring of the vibration damping spring 2-1 and is a hollow rubber ring structure, which is used to achieve the installation of the cable end suspension ear 1-4 and the free end suspension ear 1-3. The diameter of the middle positioning platform of the cable end suspension ear 1-4 and the free end suspension ear 1-3 is the same as the inner ring diameter of the hydrophone installation positioning ring 2-5. The S-shaped vibration damping structure 2-3 is a flexible rubber film located between the spring installation positioning ring 2-4 and the hydrophone installation positioning ring 2-5. Its cross-section is S-shaped and belongs to an S-shaped cross-section annular rubber spring device. A plurality of flexible holes 2-2 are circumferentially and evenly distributed and arranged at the position of the S-shaped vibration damping structure 2-3 close to the spring installation positioning ring 2-4. By increasing the number of flexible holes 2-2, the flexibility of the annular rubber spring can be further improved, the resonance frequency of the system can be reduced, and thus the acceleration response in the frequency band below 1 kHz can be reduced.

[0030] The support ring 3-1 and the pressure ring 4-1 are circular ring structures of the same size. Grooves are provided on their inner sides to achieve the clamping installation of the spring installation positioning ring 2-4. The support ring 3-1 and the pressure ring 4-1 can be made of metal or non-metal materials. Under the condition of meeting the structural strength requirements, the materials can be selected and processed according to the specific usage situation.

[0031] The support ring locking structure 3-2 is arranged at symmetric positions on both sides of the support ring 3-1, and through holes are provided thereon. The pressure ring locking structure 4-2 is arranged at symmetric positions on both sides of the pressure ring 4-1, and threaded holes are provided thereon. After the locking nut 5 passes through the through hole of the support ring locking structure 3-2, it is screwed into the threaded hole of the pressure ring locking structure 4-2 to achieve the butt joint installation of the support ring 3-1 and the pressure ring 4-1.

[0032] The support ring base 3-3 is a metal flat plate structure. Its bottom surface is perpendicular to the circular ring surface of the support ring 3-1, ensuring that the symmetry axis of the hydrophone body 1-1 is parallel to the installation plane after installation. The support ring base 3-3 and the support ring 3-1 are connected and transitioned by a neck-type structure. The middle part of the support ring base 3-3 is designed with a hollow, which can reduce the weight and installation size without losing the structural strength. The base installation holes 3-4 are symmetrically arranged on both sides of the support ring base 3-3 and are used for the firm connection of the overall structure and the bottom installation platform.

[0033] In actual application, the cable 1-2 is inserted into a hydrophone mounting and positioning ring 2-5. By using the elasticity of the hydrophone mounting and positioning ring 2-5, the cable end suspension ear 1-4 is inserted into the hydrophone mounting and positioning ring 2-5. The inner hole at the center of the hydrophone mounting and positioning ring 2-5 is fitted with the middle cylinder of the cable end suspension ear 1-4. The cable end suspension ear 1-4 can rotate, but its movement in other directions is restricted. The free end suspension ear 1-3 is inserted into another hydrophone mounting and positioning ring 2-5 by the same installation method.

[0034] Next, the cable 1-2 is inserted into the support ring 3-1, so that the base mounting hole 3-4 is located inside the hydrophone body 1-1. By using the flexibility of the damping spring 2-1, the spring mounting and positioning ring 2-4 is placed at the inner groove of the support ring 3-1. Then the cable 1-2 is inserted into the compression ring 4-1, and the spring mounting and positioning ring 2-4 is placed at the inner groove of the compression ring 4-1. The support ring 3-1 and the compression ring 4-1 are rotated so that the through hole on the support ring locking structure 3-2 is aligned with the threaded hole on the compression ring locking structure 4-2, and the locking nuts 5 on both sides are tightened. The spring mounting and positioning ring 2-4 on the other side is placed in the inner grooves of the support ring 3-1 and the compression ring 4-1 and locked by the same installation method.

[0035] When the low-acceleration-response hydrophone described in this embodiment is installed on the platform, a certain length margin of the cable 1-2 should be left for fixation, and this length margin should be greater than the maximum displacement of the low-acceleration-response hydrophone.

[0036] Although the present invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed, as long as they do not deviate from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the different dependent claims and the features described herein can be combined in a manner different from that described in the original claims. It should also be understood that the features described in connection with a single embodiment can be used in other described embodiments.

Claims

1. Low acceleration response hydrophone, characterized in that: include: A hydrophone body (1-1), two suspension ears and two vibration-damping springs (2-1), wherein the two suspension ears are respectively fixed at two ends of the hydrophone body (1-1), and the two vibration-damping springs (2-1) are respectively elastically connected to the two suspension ears; The vibration-damping spring (2-1) comprises: an S-shaped vibration-damping structure (2-3), a spring mounting positioning ring (2-4) and a hydrophone mounting positioning ring (2-5); the S-shaped vibration-damping structure (2-3) is a circular ring-shaped thin sheet structure, and the radial axial section of the circular ring-shaped thin sheet structure is S-shaped; the spring mounting positioning ring (2-4) and the hydrophone mounting positioning ring (2-5) are both circular ring-shaped and are coaxially sleeved on the outer ring and inner ring of the S-shaped vibration-damping structure (2-3), respectively; a plurality of flexible holes (2-2) are evenly arranged on the annular surface of the S-shaped vibration-damping structure (2-3) in the circumferential direction; the plurality of flexible holes (2-2) are all close to the outer ring of the S-shaped vibration-damping structure (2-3); the S-shaped vibration-damping structure (2-3), the spring mounting positioning ring (2-4) and the hydrophone mounting positioning ring (2-5) are all made of rubber.

2. The low acceleration response hydrophone according to claim 1, characterized in that: The hanging ear comprises three cylinders of different diameters arranged coaxially in a straight line, and the cylinder in the middle has the smallest diameter; The hydrophone installation positioning ring (2-5) is coaxially nested outside the cylinder located in the middle.

3. The low acceleration response hydrophone according to claim 1 or 2, characterized in that: Also includes: A support ring (3-1) and a pressure ring (4-1); The support ring (3-1) and the pressure ring (4-1) are circular ring structures with the same structure. A groove is provided on one side of the circular ring structure. The grooves of the support ring (3-1) and the pressure ring (4-1) are opposite to each other and can clamp the spring mounting positioning ring (2-4) therein.

4. The low acceleration response hydrophone according to claim 3, characterized in that: Two support ring locking structures (3-2) are provided on the outer ring of the support ring (3-1), the two support ring locking structures (3-2) are respectively located at two ends of a diameter, and the support ring locking structures (3-2) are provided with through holes; The pressure ring (4-1) is provided with two pressure ring locking structures (4-2), the two pressure ring locking structures (4-2) are respectively located at two ends of a diameter, and the pressure ring locking structure (4-2) is provided with a threaded hole; When the two support ring locking structures (3-2) and the two pressure ring locking structures (4-2) are overlapped respectively, the through hole and the threaded hole can overlap with each other and be fixed to each other via the locking nut (5).

5. The low acceleration response hydrophone according to claim 4, characterized in that: Also includes: Support ring base (3-3); The support ring base (3-3) is fixedly connected to the outer ring of the support ring (3-1), and two base mounting holes (3-4) are formed on the support ring base (3-3).

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