Bidirectional multi-stage series bending disk transducer

Abstract

The present invention provides a bidirectional multi-stage series bending disk transducer, including a folded structure, a retractable shell and a piezoelectric ceramic sheet, wherein the retractable shell is sleeved on the outside of the folded structure, and the folded structure is provided with multiple layers of piezoelectric ceramic sheets spaced apart along the axial direction, and the folded structure is provided with a first radiation end and a second radiation end along the axial direction, and the energy output directions of the first radiation end and the second radiation end are opposite. The folded structure adopts a multi-stage series piezoelectric driving method, and compared with the transducer in the prior art, under the same frequency and power conditions, the transducer is a low-frequency and high-power transducer with a smaller scale, lighter weight and higher power density. In addition, the transducer can be used as an independent small low-frequency sound source, or it can be formed into an array to achieve low-frequency and high-power operation, and it can even be used as a driving unit for certain types of low-frequency flexural transducers, which is an effective supplement to the traditional low-frequency transducer driving method.

Description

Technical Field

[0001] The invention relates to the technical field of transducers, in particular to a bidirectional multi-stage series-connected curved disk transducer. Background Art

[0002] With the technological breakthroughs of hydroacoustic systems and equipment year by year, the application scenarios and importance of hydroacoustic systems are gradually increasing. The new competition of underwater forces requires hydroacoustic systems to focus on solving problems such as long-distance communication, low-noise target recognition, and low-echo characteristic target detection. Low-frequency hydroacoustic systems are an important direction for the development of underwater forces.

[0003] As a key technology of low-frequency underwater acoustic system, low-frequency transducer technology has two important development directions:

[0004] One is the use of low-frequency, high-power and broadband, whose goal is to radiate low-frequency sound energy into the water to the greatest extent possible. In order to increase the sound source level, this type of transducer array is usually large in size and is mainly used in various types of large-scale active detection sonars on ships and shores. The lower the frequency and the greater the sound power, the stronger the underwater long-range detection capability can be obtained. The LFA large-scale low-frequency sound source array carried by the US Navy's "Impeccable" hydroacoustic survey ship weighs more than ten tons and can actively detect Fuwa submarines 130 kilometers away.

[0005] Another important development direction is the development direction of light, broadband, high efficiency and low frequency. Among various hydroacoustic and hydroacoustic countermeasure equipment and systems, most of the low-frequency sound sources are more or less restricted by platform space, load, energy and other conditions during the installation process, such as aviation dipping sonar, active buoy sonar, torpedo warning sonar active towed array, hydroacoustic transponder, hydroacoustic communication, hydroacoustic target simulator, acoustic bait, hydroacoustic jamming equipment, etc. These hydroacoustic equipment and systems are the hot spots in the current hydroacoustic field and are more widely used. They have an urgent need for small, light, low-frequency, broadband, high-efficiency and high-power sound sources.

[0006] like Figure 5As shown, it is the structure of the transducer in the prior art, wherein, Figure a is a symmetrical double-laminated curved disc transducer, and the air-backed double-laminated curved disc transducer with a symmetrical structure has been studied. This type of transducer has the characteristics of small size, low frequency, high efficiency, etc., and is suitable for engineering, but it has the disadvantage of low pressure resistance and cannot be applied in deep water fields; Figure b is a pressure-resistant curved disc transducer with an overflow cavity, which introduces seawater through the overflow port to achieve internal and external pressure balance, greatly improving the pressure resistance of the transducer. However, since the internal air cavity is replaced by seawater, the load of the transducer is reduced. In the prior art, the low-frequency transducer is generally obtained by increasing the diameter of the disc transducer. Due to the increase in the diameter of the transducer, the pressure resistance of the transducer is reduced. Although this method can obtain a lower frequency, it is at the expense of the pressure resistance. Therefore, it is necessary to design a transducer with a new structure that can obtain a lower frequency and ensure the pressure resistance of the transducer. Summary of the invention

[0007] The technical problem to be solved by the present invention is: in order to overcome the deficiency of low-frequency transducers in the prior art that cannot take into account both frequency and strength effects, the present invention provides a bidirectional multi-stage series curved disc transducer that has the characteristics of miniaturization, light weight, large load and high compressive resistance.

[0008] The technical solution adopted by the present invention to solve its technical problems is: a bidirectional multi-stage series bending disk transducer, including a folded structure, a retractable shell and a piezoelectric ceramic sheet, the retractable shell is sleeved on the outside of the folded structure, and the folded structure is provided with a first radiation end and a second radiation end along the axial direction, and the radiation directions of the first radiation end and the second radiation end are opposite. The folded structure is used to realize the series structure of the transducer, thereby reducing the frequency of the transducer while ensuring that the pressure resistance of a single transducer is not reduced, and obtaining a low-frequency transducer structure; the folded structure is provided with two radiation ends, which can meet the needs of bidirectional radiation. The node plane of the folded structure is the zero point position of the vibration amplitude, and the first radiation end and the second radiation end are symmetrical along the node plane and in opposite directions; the deformation at the node of the node plane is zero, and it can be fixed with the shell to ensure the relative stability between the shell and the folded structure, and does not affect the symmetrical energy output. When in use, the internal piezoelectric ceramics produce radial deformation under the drive of electrical signals, which will drive the folded structure to deform in the axial direction. Therefore, a retractable shell is used to ensure that the radiation surface vibrates axially.

[0009] Specifically, the folded structure includes an upper radiation cover plate, a folded portion, a neck and a lower radiation cover plate. The folded portion is a structure of multiple folded layers connected in series and is arranged between the upper radiation cover plate and the lower radiation cover plate. The adjacent folded layers and the folded layers and the upper radiation cover plate and the lower radiation cover plate are connected by necks, and the outer diameter of the neck is smaller than the outer diameter of the folded portion. The upper radiation cover plate and the lower radiation cover plate serve as energy radiation portions of the first radiation end and the second radiation end respectively; the outer diameter of the folded portion is smaller than the inner diameter of the telescopic shell, which is convenient for deformation.

[0010] Furthermore, each level of the folding layer is provided with a hollow folding cavity. The folding cavity can be an integral cavity or multiple cavities arranged in axial layers. The piezoelectric ceramic is directly arranged on a solid or rigid elastic structure to ensure sufficient compressive strength and vibration amplitude. The hollow folding cavity is arranged inside the folding layer to facilitate sufficient free space when the piezoelectric ceramic is deformed, so that the deformation energy can be transmitted.

[0011] Furthermore, an upper cone is provided on one side of the upper radiation cover plate connected to the neck, and a small end of the upper cone is connected to an adjacent neck; a lower cone is provided on one side of the lower radiation cover plate connected to the neck, and a small end of the lower cone is connected to an adjacent neck. The upper radiation cover plate and the lower radiation cover plate are configured as cone structures, which can increase the rigidity and radiation area of ​​the energy radiation end, improve the radiation characteristics, and make the radiation more uniform.

[0012] Furthermore, at least one of the upper and lower surfaces of the folding layer is provided with a piezoelectric ceramic sheet. When piezoelectric ceramic sheets are provided on both sides of the folding layer, a certain distance is provided between the upper and lower piezoelectric ceramic sheets between adjacent folding layers. The piezoelectric ceramics can be provided on only one surface of the folding layer, or on both sides to increase the driving capability, and the arrangement is performed according to the output energy requirements; since the folding layer is a series structure, when piezoelectric ceramics are provided on both sides, the piezoelectric ceramics between adjacent folding layers will face each other, therefore, in order to avoid mutual interference during vibration, a certain distance is left.

[0013] Specifically, in order to facilitate the design of the connection, the telescopic shell includes a bellows and a pressure-bearing cylinder, which are connected in series and arranged on the outside of the folded structure. The telescopic shell is divided into two parts, a telescopic bellows and a non-telescopic pressure-bearing cylinder. On the one hand, axial deformation is ensured, and on the other hand, the pressure-bearing cylinder can be used to achieve a fixed connection with the external structure. The bellows and the pressure-bearing cylinder can be connected in one piece or in a separate piece.

[0014] Furthermore, in order to facilitate the connection of the bellows with other structures, the bellows includes a first connection part, a telescopic part and a second connection part which are integrally connected, and the first connection part and the second connection part are respectively arranged at both ends of the telescopic part. The telescopic part can be extended and shortened along the axial direction, and the first connection part and the second connection part will not produce telescopic deformation, which is convenient for fixed connection with adjacent structures.

[0015] Specifically, there are two bellows, namely an upper bellows and a lower bellows, and there is one pressure-bearing cylinder. The upper bellows and the lower bellows are respectively connected to the upper and lower ends of the pressure-bearing cylinder. The upper bellows, the pressure-bearing cylinder and the lower bellows are connected in sequence to form a cylindrical structure that is sleeved on the outside of the folded structure, and the upper part of the upper bellows is connected to the upper end of the folded structure, and the lower part of the lower bellows is connected to the lower end of the folded structure.

[0016] Furthermore, in order to improve the corrosion resistance and waterproofness, a waterproof layer is provided on the outside of the folded structure, the bellows and the pressure-bearing cylinder, and the waterproof layer can be made of corrosion-resistant anti-corrosion glue.

[0017] The beneficial effects of the present invention are as follows: the present invention provides a bidirectional multi-stage series bending disk transducer, the folded structure adopts the driving mode of multi-stage series piezoelectric bending disks, and compared with the transducers in the prior art, under the same frequency and power conditions, the transducer is a low-frequency high-power transducer with smaller scale, lighter weight and higher power density. In addition, the transducer can be used as an independent small low-frequency sound source, or it can be formed into an array to achieve low-frequency high-power operation, and it can even be used as a driving unit of certain types of low-frequency flextensional transducers, which is an effective supplement to the traditional low-frequency transducer driving mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0019] Figure 1 It is a schematic structural diagram of the best embodiment of the transducer of the present invention.

[0020] Figure 2 yes Figure 1 Schematic diagram of the cross-sectional structure of the transducer.

[0021] Figure 3 It is a schematic diagram of the structure of the folded structure.

[0022] Figure 4 It is a schematic diagram of the structure of the upper / lower bellows.

[0023] Figure 5 It is the structure of the transducer in the prior art, wherein FIG. a is a schematic diagram of the structure of a symmetrical double-laminated curved disc transducer, and FIG. b is a schematic diagram of the structure of a pressure-resistant curved disc transducer with an overflow cavity.

[0024] In the figure: 1. folded structure, 11. upper radiation cover, 12. upper cone, 13. folded portion, 14. neck, 15. folded cavity, 16. lower cone, 17. lower radiation cover, 2. upper bellows, 3. pressure-bearing cylinder, 4. lower bellows, 5. piezoelectric ceramic sheet, 21. first connecting portion, 22. telescopic portion, 23. second connecting portion. DETAILED DESCRIPTION

[0025] The present invention will now be described in detail with reference to the accompanying drawings. This figure is a simplified schematic diagram, which only illustrates the basic structure of the present invention in a schematic manner, and therefore only shows the components related to the present invention.

[0026] like Figure 1 and Figure 2 As shown, a bidirectional multi-stage series bending disk transducer of the present invention includes a folded structure 1, a telescopic shell and a piezoelectric ceramic sheet 5, the telescopic shell includes a bellows and a pressure-bearing tube 3, the bellows and the pressure-bearing tube 3 are connected in series and sleeved on the outside of the folded structure 1, the folded structure 1 is provided with multiple layers of piezoelectric ceramic sheets 5 at intervals, and the folded structure 1 is axially provided with a first radiation end and a second radiation end, and the radiation directions of the first radiation end and the second radiation end are opposite. The folded structure 1 can be made of titanium alloy, stainless steel, aluminum and other materials. The pressure-bearing tube 3 is preferably made of corrosion-resistant stainless steel. The bellows can be arranged in the middle position or in two at both ends. In this embodiment, a pressure-bearing tube 3 and two upper and lower bellows, namely an upper bellows 2 and a lower bellows 4, are used as an example to explain the structure, and the structure of the pressure-bearing tube 3 and the bellows is not limited to the structure of this embodiment. The upper bellows 2 and the lower bellows 4 are respectively connected to the upper and lower ends of the pressure tube 3, and the upper bellows 2, the pressure tube 3 and the lower bellows 4 are connected in sequence to form a cylindrical structure which is sleeved on the outside of the folded structure 1, and the upper part of the upper bellows 2 is connected to the upper end of the folded structure 1, and the lower part of the lower bellows 4 is connected to the lower end of the folded structure 1.

[0027] like Figure 3As shown, the folded structure 1 comprises an upper radiation cover plate 11, an upper cone 12, a folded portion 13, a neck 14, a lower cone 16 and a lower radiation cover plate 17. The folded portion 13 is a structure of multiple folded layers connected in series and is arranged between the upper radiation cover plate 11 and the lower radiation cover plate 17. The neck 14 is used to connect the adjacent folded layers and the folded layers and the upper radiation cover plate 11 and the lower radiation cover plate 17, and the outer diameter of the neck 14 is smaller than the outer diameter of the folded portion 13. The outer diameter of the folded portion 13 is smaller than the inner diameter of the pressure tube 3; the upper cone 12 is provided on the side where the upper radiation cover plate 11 is connected to the neck 14, and the small end of the upper cone 12 is connected to the adjacent neck 14; the lower cone 16 is provided on the side where the lower radiation cover plate 17 is connected to the neck 14, and the small end of the lower cone 16 is connected to the adjacent neck 14. A hollow folded cavity 15 is provided in each level of the folded portion 13. The folded cavity 15 can be an integral cavity, or a plurality of cavities arranged in layers along the axial direction.

[0028] like Figure 2 As shown, at least one of the upper and lower sides of the folded layer is provided with a piezoelectric ceramic sheet 5. When piezoelectric ceramic sheets 5 are provided on both sides of the folded layer, a certain distance is provided between the upper and lower piezoelectric ceramic sheets 5 between adjacent folded layers.

[0029] like Figure 4 As shown, the upper bellows 2 and the lower bellows 4 have the same structure, including a first connection portion 21, a telescopic portion 22, and a second connection portion 23 that are integrally connected, and the first connection portion 21 and the second connection portion 23 are respectively arranged at both ends of the telescopic portion 22. The telescopic portion 22 can be extended and shortened along the axial direction, and the first connection portion 21 and the second connection portion 23 will not produce telescopic deformation, which is convenient for fixed connection with adjacent structures. In this embodiment, the inner sides of the ends of the first connection portion 21 and the second connection portion 23 are both provided with steps, which are respectively used to connect with the folded structure 1 and the pressure tube 3; wherein, as shown in FIG. Figure 2 As shown, the step outer diameter of the first connection part 21 of the upper bellows 2 is smaller than the outer diameter of the upper radiation cover plate 11, so that the upper radiation cover plate 11 is clamped on the first connection part step of the upper bellows 2, and the step of the second connection part 23 of the upper bellows 2 is sleeved on the upper end of the pressure tube 3; the step outer diameter of the first connection part 21 of the lower bellows 4 is smaller than the outer diameter of the lower radiation cover plate 17, so that the lower radiation cover plate 17 is clamped on the first connection part step of the lower bellows 4, and the step of the second connection part 23 of the lower bellows 4 is sleeved on the lower end of the pressure tube 3. The bellows can be made of stainless steel. In order to improve corrosion resistance, a waterproof layer is also provided on the outside of the folded structure 1, the bellows and the pressure tube 3.

[0030] Working principle:

[0031] When an electrical signal of corresponding frequency is applied to the transducer, the piezoelectric ceramic piece 5 produces radial deformation. Since the piezoelectric ceramic piece 5 is fixed on the folded layer of the folded structure 1, it will drive the folded structure 1 to produce axial expansion and contraction deformation, thereby outputting energy and realizing sound radiation.

[0032] Since the folded structure 1 is formed by connecting the folded layers of the folded cavity 15 in series, the frequency is reduced, while the diameter of the single piezoelectric ceramic 5 does not change, and the compressive strength of the transducer can be guaranteed.

[0033] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the scope of the present invention through the above description. The technical scope of this invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A bidirectional multi-stage series bending disk transducer, characterized in that: The invention comprises a folded structure, a retractable shell and a piezoelectric ceramic sheet, wherein the retractable shell is sleeved on the outside of the folded structure, a plurality of piezoelectric ceramic sheets are arranged on the folded structure at intervals along the axial direction, and the folded structure is provided with a first radiation end and a second radiation end along the axial direction, and the radiation directions of the first radiation end and the second radiation end are opposite; The folded structure includes an upper radiation cover plate, a folded portion, a neck and a lower radiation cover plate. The folded portion is a structure of multiple folded layers connected in series and is arranged between the upper radiation cover plate and the lower radiation cover plate. The adjacent folded layers and the folded layers and the upper radiation cover plate and the lower radiation cover plate are connected by a neck, and the outer diameter of the neck is smaller than the outer diameter of the folded portion.

2. The bidirectional multi-stage series-connected curved disk transducer according to claim 1, characterized in that: A hollow folding cavity is provided in each folding layer.

3. The bidirectional multi-stage series-connected curved disk transducer according to claim 1, characterized in that: An upper cone is provided on one side where the upper radiation cover is connected to the neck, and a small end of the upper cone is connected to the adjacent neck; a lower cone is provided on one side where the lower radiation cover is connected to the neck, and a small end of the lower cone is connected to the adjacent neck.

4. The bidirectional multi-stage series-connected curved disk transducer according to any one of claims 2 to 3, characterized in that: At least one of the upper and lower surfaces of the folding layer is provided with a piezoelectric ceramic sheet, and when both sides of the folding layer are provided with piezoelectric ceramic sheets, a certain distance is provided between the upper and lower piezoelectric ceramic sheets between adjacent folding layers.

5. The bidirectional multi-stage series-connected curved disk transducer according to claim 1, characterized in that: The telescopic shell comprises a bellows and a pressure-bearing cylinder, which are connected in series and arranged on the outside of the folded structure.

6. The bidirectional multi-stage series-connected curved disk transducer according to claim 5, characterized in that: The bellows comprises a first connection portion, a telescopic portion and a second connection portion which are integrally connected, wherein the first connection portion and the second connection portion are respectively arranged at two ends of the telescopic portion.

7. The bidirectional multi-stage series-connected curved disk transducer according to claim 5, characterized in that: There are two bellows, namely an upper bellows and a lower bellows, and there is one pressure-bearing cylinder. The upper bellows and the lower bellows are respectively connected to the upper and lower ends of the pressure-bearing cylinder. The upper bellows, the pressure-bearing cylinder and the lower bellows are connected in sequence to form a cylindrical structure that is sleeved on the outside of the folded structure, and the upper part of the upper bellows is connected to the upper end of the folded structure, and the lower part of the lower bellows is connected to the lower end of the folded structure.

8. The bidirectional multi-stage series-connected curved disk transducer according to claim 5, characterized in that: A waterproof layer is also provided on the outer sides of the folded structure, the corrugated pipe and the pressure-bearing cylinder.

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