A moving magnet type driving magnetic circuit and a static water pressure resistant high-power double moving magnet type driving stack

Abstract

The application provides a moving magnet type driving magnetic circuit and a static water pressure resistant high-power double moving magnet type driving stack, and belongs to the field of underwater acoustic transducers. The application solves the problems of insufficient use depth and small transmitting power of existing super low frequency transducers. The application comprises a moving magnet type driving magnetic circuit and a magnetic circuit fixing structure, a permanent magnet mounting frame, a permanent magnet array, a permanent magnet mounting frame, a steel sheet spring, a coil, a coil skeleton, a wire, a water-proof filling treatment, a magnetic core, a mounting frame, a horizontal beam and a connecting seat. The application is mainly used for driving underwater acoustic transducers.

Description

Technical Field

[0001] This invention belongs to the field of underwater acoustic transducers, and in particular relates to a moving magnetic drive circuit and a high-power dual moving magnetic drive stack resistant to hydrostatic pressure. Background Technology

[0002] Low-frequency sound waves, especially ultra-low-frequency (ULF) sound waves with frequencies below 200Hz, have immense application value. On one hand, with the widespread use of anechoic tiles and the development of vibration reduction and noise reduction technologies, submarine detection using passive or high-frequency active sonar is becoming increasingly difficult. Therefore, using ULF sonar for active detection has become an effective method. On the other hand, when sound waves propagate in water, the lower the frequency, the slower the attenuation. Therefore, ULF sound waves can propagate over extremely long distances in water, which is beneficial for increasing the effective range of sonar. In civilian applications, ULF sound waves are also widely used in marine acoustic tomography, ground acoustics research, and other fields.

[0003] The generation of ultra-low frequency (UHF) sound waves in water relies on UHF underwater acoustic transducers. Generally, the lower the transducer frequency, the larger and heavier it becomes. Transducers made of traditional driving materials such as piezoelectric and magnetostrictive materials are extremely large and heavy to achieve UHF transmission. Electromagnetic drive is an ideal driving source for UHF transducers, based on the principle of electromagnetic interaction. An electromagnetic transducer can typically be considered a single-degree-of-freedom vibration system. The main operating mode of the transducer is the piston-like vibration of the radiating surface and its connecting parts. The stiffness of the vibration system is provided by the elastic elements of the transducer. Because the stiffness can be designed, UHF transmission is easily achieved. Common electromagnetic driven transducers include electrodynamic transducers and moving-magnetic transducers. Moving-magnetic transducers have a higher power limit and are more suitable as driving sources for high-power UHF transducers. Traditional moving-magnetic transducers are air-backed and have a maximum operating depth of tens of meters. As my country's marine research increasingly extends to the deep sea, the demand for deep-sea transducers is becoming more and more urgent. In order to increase the operating depth of transducers, it is necessary to watertighten the transducer drive part to facilitate the manufacture of overflow transducers, thereby increasing the working depth of transducers. Summary of the Invention

[0004] In view of this, the present invention aims to propose a moving-magnet drive magnetic circuit and a hydrostatic pressure-resistant high-power dual moving-magnet drive stack to solve the problems of insufficient application depth and low transmission power of existing ultra-low frequency transducers.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a moving magnetic drive magnetic circuit, comprising a magnetic core, a coil, and a permanent magnet array. The magnetic core consists of two C-shaped structures, with their openings facing each other. A coil is connected to both ends of each magnetic core. The permanent magnet array includes a first permanent magnet and a second permanent magnet. Two first permanent magnets are respectively positioned on either side of a second permanent magnet. The size of the first permanent magnet is smaller than that of the second permanent magnet. Both the first and second permanent magnets are rectangular plate structures with polarization in the thickness direction. The magnetic poles of the first and second permanent magnets are opposite in direction. The permanent magnet array is positioned in the exact center of the two magnetic cores, with the connection gap between the first and second permanent magnets located in the middle of the magnetic poles of the magnetic core.

[0006] This invention also provides a hydrostatic pressure-resistant, high-power dual-moving-magnet drive stack, comprising two single-moving-magnet sub-drive stacks. Each single-moving-magnet sub-drive stack includes a moving-magnet drive magnetic circuit and a magnetic circuit fixing structure. The magnetic circuit fixing structure includes a permanent magnet mounting frame and a mounting frame. The permanent magnet mounting frame has a mounting through hole in the middle, and a permanent magnet array is arranged inside the mounting through hole. The permanent magnet mounting frame is located in the middle of the mounting frame, and steel leaf springs are respectively connected to both ends of the permanent magnet mounting frame. The two ends of the steel leaf springs are connected to the mounting frame. The coil includes a coil frame and wires, and the wires are wound around the coil frame. The coil is watertight and potted. The coil frame is sleeved on the magnetic core. A magnetic core is set at each of the upper and lower ends of the mounting frame. The magnetic core is connected and fixed to the mounting frame through a crossbeam. The two single-acting magnetic drive stacks are longitudinally connected by a connecting seat. Two support plates are set on the top surface of the upper single-acting magnetic drive stack and the bottom surface of the lower single-acting magnetic drive stack. Radial bases are connected to both sides of the permanent magnet mounting frame of the two single-acting magnetic drive stacks. The support plates and the radial bases are connected by a helical spring. The two single-acting magnetic drive stacks are connected in parallel in the circuit.

[0007] Furthermore, the coil frame is provided with a watertight groove, and watertight sealing treatment is performed using potting epoxy.

[0008] Furthermore, the magnetic core has several core slits on both sides.

[0009] Furthermore, the permanent magnet array is bonded to the permanent magnet mounting bracket using epoxy adhesive.

[0010] Furthermore, both the first and second permanent magnets in the permanent magnet array are neodymium iron boron rare earth permanent magnets.

[0011] Furthermore, the two ends of the helical spring are screwed together with the front connecting seat and the rear connecting seat respectively. The front connecting seat is connected to the radial surface base, and the rear connecting seat is connected to the support plate.

[0012] Furthermore, the permanent magnet mounting bracket end face and the mounting frame side face are provided with slots, the steel spring is snapped into the slots, the steel spring is connected to the permanent magnet mounting bracket through the middle pressure block, and the steel spring is connected to the mounting frame through the pressure blocks at both ends.

[0013] Furthermore, the magnetic core has a groove, and the crossbeam and the magnetic core have grooves that cooperate with each other, and the crossbeam is connected to the mounting frame.

[0014] Furthermore, the mounting frame is made of aluminum, the connecting seat is connected to the mounting frame, and the support plate is connected to the mounting frame.

[0015] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention provides a novel moving-magnet drive circuit and a high-power dual-moving-magnet drive stack using this moving-magnet drive circuit, which is resistant to hydrostatic pressure. This drive stack features high power, high efficiency, hydrostatic pressure resistance, compact structure, and adjustable resonant frequency. This invention achieves watertightness and hydrostatic pressure resistance by potting the drive coil; reduces eddy current losses and improves the drive stack's efficiency by slitting the magnetic core; increases the output power of the drive stack by employing a dual-excitation parallel drive design; and incorporates a spring mounting structure, allowing adjustment of the transducer's resonant frequency by changing the spring stiffness. This drive stack can serve as the drive source for a high-power ultra-low frequency deep-sea acoustic transducer.

[0016] The hydrostatic pressure-resistant, high-power dual-moving-magnet drive reactor utilizes a novel moving-magnet drive circuit. This circuit comprises two magnetic cores, three permanent magnets, and four coils, featuring a compact structure and high space utilization. This circuit boasts a higher power density, providing greater output power within the same volume. The drive reactor employs a parallel configuration of two moving-magnet drive reactors, further increasing output power. By potting the coils, the drive reactor acquires hydrostatic pressure resistance, enabling its application in deep-sea environments. The design of the support plate and radial base allows for the connection of helical springs, giving the drive reactor the ability to adjust its resonant frequency. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0018] Figure 1 This is a schematic diagram of the basic magnetic circuit model structure of a moving magnet type drive magnetic circuit according to the present invention;

[0019] Figure 2 This is a schematic diagram of the magnetic core structure described in this invention;

[0020] Figure 3 This is a schematic diagram of the coil frame structure described in this invention;

[0021] Figure 4 This is a schematic diagram of the permanent magnet mounting frame structure described in this invention;

[0022] Figure 5 This is a schematic diagram of the three-dimensional structure of the single-acting magnetic sub-driven stack described in this invention;

[0023] Figure 6 This is a schematic diagram of the cross-sectional structure of the single-acting magnetic sub-driven stack described in this invention;

[0024] Figure 7 This is a schematic diagram of a three-dimensional structure of a high-power dual-moving magnetic drive stack resistant to hydrostatic pressure, as described in this invention.

[0025] Figure 8 This is a schematic diagram of the cross-sectional structure of a high-power dual-moving magnetic drive stack resistant to hydrostatic pressure, as described in this invention.

[0026] In the diagram: 1-Magnetic core, 2-Coil, 3-First permanent magnet, 4-Second permanent magnet, 5-Core slit, 6-Coil frame, 7-Watertight groove, 8-Permanent magnet mounting bracket, 9-Mounting through hole, 10-Mounting frame, 11-Steel leaf spring, 12-Intermediate pressure block, 13-End pressure blocks, 14-Crossbeam, 15-Connecting seat, 16-Radiating base, 17-Helical spring, 18-Front connecting seat, 19-Rear connecting seat, 20-Support plate. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other, and the described embodiments are only some embodiments of the present invention, not all embodiments.

[0028] See Figure 1This embodiment describes a moving-magnet drive magnetic circuit, comprising a magnetic core 1, a coil 2, and a permanent magnet array. There are two magnetic cores 1, each with a C-shaped structure, positioned opposite each other at their openings. A coil 2 is connected to both ends of each magnetic core 1. The permanent magnet array includes two different sizes of first permanent magnets 3 and second permanent magnets 4. A larger second permanent magnet 4 is placed in the center, and smaller first permanent magnets 3 are placed on either side. The magnetic poles of the central second permanent magnet 4 are opposite to those of the two first permanent magnets 3. Both the first and second permanent magnets 3 and 4 are rectangular plate structures with opposite magnetic pole directions. The magnetic pole directions of the permanent magnet array and the corresponding current flow directions of the coils 2 are... Figure 1 As indicated, the permanent magnet array is positioned in the exact middle of the two magnetic cores 1, and the connection gap between the first permanent magnet 3 and the second permanent magnet 4 is located in the middle of the magnetic poles of the magnetic core 1. This ensures that when the magnetic circuit is in a static state, i.e. when no current flows through the coil 2, the static attraction forces of the two magnetic cores 1 on the permanent magnet array can cancel each other out.

[0029] See Figure 2-8 This embodiment describes a hydrostatic pressure-resistant, high-power dual-moving-magnetic drive stack, comprising two single-moving-magnetic sub-drive stacks. Each single-moving-magnetic sub-drive stack includes a moving-magnetic drive magnetic circuit and a magnetic circuit fixing structure. The magnetic circuit fixing structure includes a permanent magnet mounting frame 8 and a mounting frame 10. The permanent magnet mounting frame 8 has a mounting through hole 9 in the middle, and a permanent magnet array is arranged inside the mounting through hole 9. The permanent magnet mounting frame 8 is located in the middle of the mounting frame 10, and steel sheet springs 11 are connected to both ends of the permanent magnet mounting frame 8. The two ends of the steel sheet springs 11 are connected to the mounting frame 10. The coil 2 includes a coil frame 6 and a wire. The wire is wound on the coil frame 6. The coil 2 is watertight. The coil frame 6 is sleeved on a magnetic core 1. A magnetic core 1 is arranged at each of the upper and lower ends of the mounting frame 10. The magnetic core 1 is connected and fixed to the mounting frame 10 through a crossbeam 14.

[0030] The mounting frame 10 is made of aluminum. The mounting frame 10 and the crossbeam 14 are used to fix the magnetic core 1 in the moving magnet drive magnetic circuit. The permanent magnet mounting bracket 8 is used to place the permanent magnet array. The steel spring 11 is used to limit the permanent magnet array and prevent the permanent magnet from being attracted to the magnetic core 1. The structure and size of the mounting frame 10 are determined according to the size of the magnetic circuit. The mounting frame 10 cooperates with the crossbeam 14, the steel spring 11 and the steel spring pressure block to fix the magnetic circuit and ensure that the various parts of the magnetic circuit will not shift in position.

[0031] like Figure 2As shown, the magnetic core 1 has several core slits 5 on both sides. These slits are designed to reduce eddy current losses. Since eddy currents always flow on the conductor surface, slitting increases the surface area, lengthens the eddy current flow path, increases the eddy current resistance, reduces losses, improves the uniformity and strength of the magnetic field in the drive stack's magnetic gap, and increases the drive stack's efficiency. The more slits, the better the eddy current suppression effect. The magnetic core 1 has slots, and the crossbeam 14 matches these slots. The crossbeam 14 is connected to the mounting frame 10.

[0032] like Figure 3 As shown, the coil frame 6 is provided with a watertight groove 7. Watertight encapsulation is performed using potting epoxy, which can ensure watertightness and resistance to hydrostatic pressure. The potting uses a specially designed potting mold, with the coil frame 6 also serving as part of the mold. During potting, the epoxy fills the watertight groove 7, making the watertight effect of the potting scheme more reliable.

[0033] like Figure 4 As shown, the permanent magnet array is bonded to the permanent magnet mounting frame 8 using epoxy adhesive. During installation, the permanent magnet mounting frame 8 and the permanent magnet array are bonded together using adhesive epoxy. During bonding, the first permanent magnet 3 and the second permanent magnet 4 are first arranged according to the designed magnetic pole direction. Then, a layer of adhesive epoxy is evenly applied to the top, bottom, and sides of each surface of the permanent magnet array. The permanent magnet array is then placed into the mounting through-hole 9, and the two large planes of the permanent magnet mounting frame 8 are clamped with a fixture to ensure tight contact between the permanent magnet array and the permanent magnet mounting frame 8. To prevent demagnetization of the permanent magnet array, the bonding and drying temperature should not be too high. The first permanent magnet 3 and the second permanent magnet 4 in the permanent magnet array are both neodymium iron boron rare earth permanent magnets.

[0034] The permanent magnet mounting bracket 8 and the mounting frame 10 both have slots on their end faces and sides. The steel spring 11 is engaged in these slots and is connected to the permanent magnet mounting bracket 8 via a central pressure block 12. The steel spring 11 is also connected to the mounting frame 10 via end pressure blocks 13. The steel spring 11 restricts the position of the permanent magnet array. When the permanent magnet array deviates from the magnetic core 1 and is attracted by the magnetic core 1, the restoring force provided by the steel spring 11 must be greater than the magnetic core 1's attraction force to maintain the permanent magnet array's position within the magnetic gap.

[0035] like Figure 5 and Figure 6As shown, the above structure constitutes a single-acting magnetic drive stack. During assembly, with the mounting frame 10 as the center, first place the bonded permanent magnet array and permanent magnet mounting bracket 8 in the middle of the mounting frame 10. Then, assemble the permanent magnet mounting bracket 8 with the steel spring 11 and the intermediate pressure block 12. Next, assemble the two ends of the steel spring 11 with the mounting frame 10 and the two end pressure blocks 13. At this time, the permanent magnet mounting bracket 8 is fixed on the mounting frame 10. The coil frame 6 is fitted onto the magnetic core 1 and fixed with epoxy. Then, two magnetic cores 1 are installed from the top and bottom of the mounting frame 10. The magnetic cores 1 are fixed to the mounting frame 10 with the crossbeam 14. At this point, the assembly of a single-acting magnetic drive stack is completed.

[0036] like Figure 7 and Figure 8 As shown, the two single-acting magnetic sub-drive stacks are longitudinally connected by a connecting seat 15. Two support plates 20 are provided on the top surface of the upper single-acting magnetic sub-drive stack and the bottom surface of the lower single-acting magnetic sub-drive stack. Radial bases 16 are connected to both sides of the permanent magnet mounting frame 8 of the two single-acting magnetic sub-drive stacks. The support plates 20 and the radial bases 16 are connected by a helical spring 17. In order to ensure that the output force of the two single-acting magnetic sub-drive stacks is in the same direction, the two single-acting magnetic sub-drive stacks are connected in parallel in the circuit. When connecting the cables, it is necessary to ensure that the circuit is connected in parallel.

[0037] The two ends of the helical spring 17 are screwed into the front connecting seat 18 and the rear connecting seat 19, respectively. The front connecting seat 18 is connected to the radiating surface base 16, and the rear connecting seat 19 is connected to the support plate 20. The helical spring 17 is designed according to the transducer's operating frequency. To facilitate the installation of the helical spring 17, a front connecting seat 18 and a rear connecting seat 19 are designed at both ends of the helical spring 17. One end of the front connecting seat 18 and the rear connecting seat 19 can be screwed into the helical spring 17, and the other end is designed as a screw to connect with other parts.

[0038] The connecting seat 15 is connected to the mounting frame 10, and the support plate 20 is connected to the mounting frame 10. The connecting seat 15 is used to fix and connect two single-acting magnetic drive units, the helical spring 17 is used to provide stiffness for the vibration system, and the support plate 20 is used to connect the helical spring 17 and the mounting frame 10. When used as a transducer drive source, the support plate 20 can be connected to the transducer housing.

[0039] The radiating surface base 16 is used to connect the helical spring 17 and the radiating surface of the transducer. The radiating surface base 16 is connected to the helical spring 17 and the permanent magnet mounting frame 8. The resultant force of the two single-acting magnetic sub-drive units acts on the radiating surface base 16. When used as a transducer drive source, the radiating surface can be installed at the other end of the radiating surface base 16.

[0040] The working principle of this invention is as follows: Figure 1Based on the moving magnet drive magnetic circuit shown, when the dual moving magnet drive stack is working, the coil 2 is energized with alternating current, generating an alternating magnetic field that interacts with the magnetic field of the permanent magnet array, generating a lateral force that causes the permanent magnet array to move laterally. This force is transmitted through the permanent magnet mounting frame 8 to the radiating surface base 16, causing the radiating surface connected to the radiating surface base 16 to vibrate.

[0041] The embodiments of the present invention disclosed above are merely illustrative of the invention. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A hydrostatic pressure resistant high-power double-acting magnetic drive stack, the drive stack serving as a drive source of a high-power ultra-low frequency deep-sea underwater acoustic transducer, characterized in that: It includes two single-acting magnetic sub-drives, the single-acting magnetic sub-drive includes a moving magnetic drive magnetic circuit and a magnetic circuit fixed structure, the moving magnetic drive magnetic circuit includes a magnetic conductive core (1), a coil (2) and a permanent magnet array, the number of the magnetic conductive core (1) is two, both of the two magnetic conductive cores (1) are C-shaped structures, the openings of the two C-shaped structures are oppositely arranged, the two ends of each magnetic conductive core (1) are sleeved with a coil (2), the permanent magnet array includes a first permanent magnet (3) and a second permanent magnet (4), the number of the first permanent magnet (3) is two, the two first permanent magnets (3) are arranged on the two sides of the second permanent magnet (4) respectively, the size of the first permanent magnet (3) is smaller than that of the second permanent magnet (4), both of the first permanent magnet (3) and the second permanent magnet (4) are rectangular plate structures, the polarization direction is the thickness direction, the magnetic pole directions of the first permanent magnet (3) and the second permanent magnet (4) are opposite, the permanent magnet array is arranged in the middle of the two magnetic conductive cores (1) and the connecting gap of the first permanent magnet (3) and the second permanent magnet (4) is located in the middle of the magnetic pole of the magnetic conductive core (1), the magnetic circuit fixed structure includes a permanent magnet mounting frame (8) and a mounting frame (10), the permanent magnet mounting frame (8) is provided with a mounting through hole (9) in the middle, the permanent magnet array is arranged in the mounting through hole (9), the permanent magnet mounting frame (8) is arranged in the middle of the mounting frame (10), both ends of the permanent magnet mounting frame (8) are connected with a steel sheet spring (11), both ends of the steel sheet spring (11) are connected with the mounting frame (10), the coil (2) includes a coil skeleton (6) and a wire, the wire is wound on the coil skeleton (6), the coil (2) is subjected to water-tight pouring treatment, the coil skeleton (6) is sleeved on the magnetic conductive core (1), one magnetic conductive core (1) is arranged at each of the upper and lower ends of the mounting frame (10), the magnetic conductive core (1) is connected and fixed with the mounting frame (10) through a cross beam (14), a plurality of core cutting slots (5) are arranged on the two sides of the magnetic conductive core (1), the two single-acting magnetic sub-drives are longitudinally connected through a connecting seat (15), the top surface of the upper single-acting magnetic sub-drive and the bottom surface of the lower single-acting magnetic sub-drive are both provided with two supporting plates (20), the two sides of the permanent magnet mounting frame (8) of the two single-acting magnetic sub-drives are both connected with a radiation surface base (16), the supporting plate (20) and the radiation surface base (16) are connected through a spiral spring (17), the two single-acting magnetic sub-drives are connected in parallel on the circuit, the radiation surface base (16) is used for connecting the radiation surface of a transducer, and the spiral spring (17) is designed according to the working frequency of the transducer.

2. A hydrostatically resistant high power double acting magnetic drive stack according to claim 1, characterized in that: The coil skeleton (6) is provided with a water-tight groove (7), and the water-tight pouring treatment is performed by using pouring epoxy.

3. A hydrostatically resistant high power double acting magnetic drive stack according to claim 1, characterized in that: The permanent magnet array is connected by being bonded with the permanent magnet mounting frame (8) by using epoxy glue.

4. The hydrostatically resistant high power double acting magnetic drive stack of claim 1, wherein: Both of the first permanent magnet (3) and the second permanent magnet (4) in the permanent magnet array are neodymium iron boron rare earth permanent magnets.

5. A hydrostatically resistant high power double acting magnetic drive stack according to claim 1, characterized in that: Two ends of the helical spring (17) are respectively screwed to the front connecting seat (18) and the rear connecting seat (19), the front connecting seat (18) is connected to the radiation surface base (16), and the rear connecting seat (19) is connected to the supporting plate (20).

6. A hydrostatically resistant high power double acting magnetic drive stack according to claim 1, characterized in that: The end face of the permanent magnet mounting frame (8) and the side face of the mounting frame (10) are both provided with notches, the steel sheet spring (11) is clamped in the notches, the steel sheet spring (11) is connected to the permanent magnet mounting frame (8) through the middle pressing block (12), and the steel sheet spring (11) is connected to the mounting frame (10) through the two end pressing blocks (13).

7. A hydrostatically resistant high power double acting magnetic drive stack according to claim 1, characterized in that: The magnetic guide core (1) is provided with a groove, the cross beam (14) is matched with the groove on the magnetic guide core (1), and the cross beam (14) is connected to the mounting frame (10).

8. A hydrostatically resistant high power double acting magnetic drive stack according to claim 1, characterized in that: The mounting frame (10) is made of aluminum, the connecting seat (15) is connected to the mounting frame (10), and the supporting plate (20) is connected to the mounting frame (10).

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