Spherical underwater acoustic transducer based on 3D metal printing

Abstract

The invention discloses a spherical underwater acoustic transducer based on 3D metal printing, and belongs to the technical field of 3D metal printing, the spherical underwater acoustic transducer comprises a metal spherical shell and a sensing part arranged in the metal spherical shell, an upper end cover is arranged on the sensing part, a circle of first convex edge is arranged on the lower surface of the upper end cover, and the first convex edge and the sensing part are clamped and restrained; the metal spherical shell is connected with the periphery of the upper end cover, a containing cavity is formed in the metal spherical shell through 3D printing, a circle of second convex edge is arranged at the bottom of the containing cavity, the sensing component is arranged in the second convex edge and restrained with the second convex edge, and a set of annular cavities not communicated with the containing cavity are formed in the bottom of the metal spherical shell. Through the stable structure of the metal spherical shell, the upper end cover and the sensing part generated through 3D integrated printing and the annular cavity in the metal spherical shell, the bandwidth of the spherical underwater acoustic transducer can be stably widened, and then the spherical underwater acoustic transducer can stably and effectively transmit or receive ultrasonic waves with more frequencies.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D metal printing, and in particular to a spherical underwater acoustic transducer based on 3D metal printing. Background Art

[0002] 3D metal printing, also known as additive manufacturing, can directly produce three-dimensional models by controlling the selective accumulation of materials. The fused deposition modeling (FDM) process extrudes the filamentary, metallic material from the nozzle by heating, and selectively prints the material on the workbench according to the predetermined trajectory of the model slice to form it.

[0003] As an underwater sensor, the spherical hydroacoustic transducer converts electrical energy into mechanical energy through a sensing component, and then transmits the mechanical energy to the sensor housing through the sensor's accommodating cavity, so that the mechanical energy is converted into acoustic energy and emitted. It plays a very important role in the detection of the marine environment. The prior art uses 3D printing to print a spherical transducer with a metal housing using metal as the material, and the spherical housing of the transducer is integrally formed with the internal sensing component through 3D metal printing. However, the 3D metal-printed spherical housing and the internal sensing component of the prior art are not tightly constrained, resulting in structural misalignment between the spherical housing and the sensing component when high-frequency mechanical energy and acoustic energy are converted, which in turn causes the working bandwidth of the spherical hydroacoustic transducer to be unstable. In addition, the transducer housing of the prior art is only spherical, and it is impossible to broaden the working bandwidth of the spherical hydroacoustic transducer while maintaining a stable structure, which in turn makes it impossible for the spherical hydroacoustic transducer to stably and effectively transmit or receive ultrasonic waves of more frequencies. Summary of the invention

[0004] In order to solve the technical problems mentioned in the above background technology, the present invention provides a spherical underwater acoustic transducer based on 3D metal printing, and the technical solution adopted is as follows:

[0005] The invention comprises a metal spherical shell and a sensing component arranged inside the metal spherical shell. The metal spherical shell and the sensing component are integrally formed by 3D printing. An upper end cover is arranged on the sensing component. A circle of first convex edges is arranged on the lower surface of the upper end cover. The first convex edges are engaged and constrained with the upper part of the sensing component. The metal spherical shell is connected to the upper end cover on all sides. An accommodating cavity is formed inside the metal spherical shell by 3D printing. A circle of second convex edges is arranged at the bottom of the accommodating cavity. The sensing component is arranged in the second convex edges and is constrained with the second convex edges. A group of annular cavities which are not connected with the accommodating cavity are arranged at the bottom of the metal spherical shell.

[0006] Furthermore, the sensing component includes: a group of intermediate mass blocks, piezoelectric ceramic stacks are pressed between the intermediate mass blocks, third convex edges are arranged on both sides of the intermediate mass blocks, the piezoelectric ceramic stacks are arranged on the inner side of the third convex edges and are mutually constrained with the third convex edges; piezoelectric ceramic stacks, each piezoelectric ceramic stack is composed of multiple piezoelectric ceramic sheets, and the piezoelectric ceramic sheets are made of piezoelectric ceramic materials; conductor copper sheets, the conductor copper sheets are arranged on the piezoelectric ceramic stacks, and leads are arranged on both sides of the conductor copper sheets.

[0007] Furthermore, a group of openings are provided on the upper end cover, and the lead wires pass through the openings.

[0008] Furthermore, the metal spherical shell and the upper end cover are sealed by epoxy resin glue.

[0009] Furthermore, the accommodating cavity is in a teardrop shape.

[0010] Furthermore, the annular cavity is tightly connected to the metal spherical shell by 3D metal printing or aluminum welding.

[0011] Furthermore, the metal material in the metal spherical shell is aluminum.

[0012] The present invention has the following advantages: by embedding the sensing component in the accommodating cavity of the 3D integrally printed metal spherical shell, through the mutual constraint between the second convex edge and the sensing component, the mutual constraint between the sensing components, and the mutual constraint between the metal spherical shell, the upper end cover and the sensing component, the metal spherical shell and the sensing component are structurally stable and will not be misaligned when high-frequency mechanical energy and acoustic energy are converted, thereby making the working bandwidth of the metal spherical underwater acoustic transducer stable. On this basis, an annular cavity is arranged on the metal spherical shell, and when the transducer works in water, the annular cavity will resonate, that is, the liquid in the annular cavity will resonate to generate a resonance peak, and this resonance peak will coincide with other resonance modes of the transducer (such as shell vibration, piezoelectric material vibration) The annular cavity can be coupled with the spherical acoustic transducer (such as a spherical shell, an upper end cover, and a sensing component) to change the overall resonance characteristics of the transducer, so that the annular cavity can further constrain and expand its amplitude, and finally widen the available working bandwidth and reduce the fluctuation of the emission voltage response within the available working bandwidth, so that the entire spherical acoustic transducer can stably widen the bandwidth. Secondly, the annular cavity can collect the oblique force generated by the intermediate mass block on the sphere during vibration and feed it back into a longitudinal force through extrusion to increase its amplitude. The present invention uses a stable structure of a metal spherical shell, an upper end cover, and a sensing component generated by 3D integrated printing, and an annular cavity on the metal spherical shell, so that the spherical acoustic transducer can stably widen the bandwidth, and then the spherical acoustic transducer can stably and effectively transmit or receive ultrasonic waves of more frequencies. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural diagram of the present invention.

[0014] Figure 2For the present invention Figure 1 A partial enlarged view of point a in the middle.

[0015] Figures: 1 metal spherical shell, 2 upper end cover, 3 first flange, 4 opening, 5 accommodating cavity, 6 second flange, 7 annular cavity, 8 intermediate mass block, 9 piezoelectric ceramic stack, 10 third flange, 11 piezoelectric ceramic sheet, 12 conductor copper sheet, 13 lead wire. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] The present invention provides a spherical underwater acoustic transducer based on 3D metal printing, please refer to Figure 1-2 , including a metal spherical shell 1 and a sensor component arranged inside the metal spherical shell 1, the metal spherical shell 1 and the sensor component are 3D printed as a whole, wherein the metal spherical shell 1 is 3D printed as a whole and attached to the sensor component, an upper end cover 2 is arranged on the sensor component, a circle of first convex edges 3 are arranged on the lower surface of the upper end cover 2, the first convex edges 3 are engaged and constrained with the upper part of the sensor component, the metal spherical shell 1 is connected with the upper end cover 2 all around, the upper end cover 2 forms a seal with the metal spherical shell 1, when the spherical hydroacoustic transducer is placed in water to work, liquid is prevented from entering the metal spherical shell 1 to affect the sensor component, and the metal spherical shell 1 is The accommodating cavity 5 is formed by 3D printing, and the mechanical energy converted from electrical energy is diffused to the metal spherical shell 1 through the accommodating cavity 5. A circle of second convex edges 6 is arranged at the bottom of the accommodating cavity 5. The sensing component is arranged in the second convex edge 6 and constrained with the second convex edge 6. The sensing component is constrained and clamped between the first convex edge 3 and the second convex edge 6 through the upper end cover 2, so that the metal spherical shell 1, the upper end cover 2 and the sensing component are firmly constrained, and the sensing components are also firmly constrained with each other, so that the sensing component will not vibrate and misalign when the mechanical energy and acoustic energy are converted. A group of annular cavities 7 that are not connected to the accommodating cavity 5 are arranged at the bottom of the metal spherical shell 1.

[0018] The sensing component includes a group of intermediate mass blocks 8, between which piezoelectric ceramic stacks 9 are pressed, and the intermediate mass blocks 8 and the piezoelectric ceramic stacks 9 are a combination, which are assembled, and the intermediate mass blocks 8 are provided with third convex edges 10 on both sides, and the piezoelectric ceramic stacks 9 are arranged on the inner side of the third convex edge 10 and constrained with the third convex edge 10, so that the piezoelectric ceramic stacks 9 and the third convex edge 10 are pressed firmly up and down, and are fastened all around without misalignment, and each piezoelectric ceramic stack 9 is composed of multiple piezoelectric ceramic sheets 11, and the piezoelectric ceramic The sheet 11 is made of piezoelectric ceramic material, which has a strong ability to convert mechanical energy into electrical energy. The conductor copper sheet 12 is arranged on the piezoelectric ceramic stack 9. Leads 13 are arranged on both sides of the conductor copper sheet 12. The lead 13 is connected to the power supply. When power is turned on, electrical energy is transferred to the conductor copper sheet 12 through the lead 13, and then the piezoelectric ceramic stack 9 is operated. A group of openings 4 are arranged on the upper end cover 2, and the lead 13 passes through the opening 4. The lead 13 is the same size as the opening diameter, so that a seal is formed between the lead 13 and the opening 4.

[0019] The metal spherical shell 1 and the upper end cover 2 are sealed by epoxy resin glue. The epoxy resin glue has strong bonding force, good sealing performance, and is resistant to corrosion by seawater.

[0020] The accommodating cavity 5 is in a teardrop shape, which optimizes the stability of the available working bandwidth at -6dB compared to a spherical shape. The metal material in the metal spherical shell 1 is aluminum, which is thin and light and corrosion-resistant, thereby extending the service life of the spherical hydroacoustic transducer.

[0021] The working principle of the present invention is as follows: a metal spherical shell 1 is formed by 3D metal printing, and a second convex edge 6 and an annular cavity 7 on the spherical metal shell 1 are printed at the same time of 3D metal printing, and a receiving cavity is formed in the printed metal spherical shell 1, and the upper part of the metal spherical shell 1 is a through-opening structure;

[0022] One of the intermediate mass blocks 8 is placed in the second convex edge 6, and one of the piezoelectric ceramic stacks 9 is placed in the third convex edge 10, as shown in FIG. Figure 1 As shown in the figure, the lead wire 13 is replaced through the opening 4, and then the upper end cover 2 is covered on the through-hole structure on the upper part of the metal spherical shell 1, and the uppermost intermediate mass block 8 is inserted into the first convex edge 3, and then epoxy resin glue is dripped into the gap between the metal spherical shell 1 and the upper end cover 2 to fix and seal the two. At this time, the metal spherical shell 1, the upper end cover 2, the intermediate mass block 8 and the piezoelectric ceramic stack 9 are mutually constrained and firmly.

[0023] After assembly, the entire spherical hydroacoustic transducer is placed in water. After power is turned on, the piezoelectric ceramic sheets 11 bend and deform under the action of the piezoelectric effect, and the deformation of the piezoelectric ceramic stack 9 is expanded in opposite directions in pairs, so as to convert the electrical energy into mechanical energy. Then, through the repeated deformation of the piezoelectric ceramic stack 9, the mechanical energy of the vibration is transmitted to the metal spherical shell 1 and the annular cavity 7 through the intermediate mass block 8. Then, through the vibration of the metal spherical shell 1, the mechanical energy is converted into acoustic energy and transmitted through the seawater. During the transmission process, the annular cavity 7 will resonate, that is, the liquid in the annular cavity 7 will resonate and generate a resonance peak. This resonance peak will couple with other resonance modes of the spherical hydroacoustic transducer (such as shell vibration, piezoelectric material vibration, etc.), thereby changing the overall resonance characteristics of the spherical hydroacoustic transducer, so that the annular cavity 7 further constrains and expands its amplitude, and finally achieves the purpose of broadening the available working bandwidth and reducing the fluctuation of the emission voltage response within the available working bandwidth, so that the entire spherical hydroacoustic transducer can stably broaden the bandwidth.

[0024] The present invention is simple to operate, convenient to use, and suitable for comprehensive promotion and application. Although the embodiments of the present invention have been shown and described, it is understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A spherical underwater acoustic transducer based on 3D metal printing, comprising a metal spherical shell (1) and a sensing component arranged inside the shell, characterized in that: The metal spherical shell (1) and the sensor component are integrally formed by 3D printing, an upper end cover (2) is provided on the sensor component, a circle of first convex edges (3) are provided on the lower surface of the upper end cover (2), the first convex edges (3) are engaged and constrained with the upper part of the sensor component, the metal spherical shell (1) and the upper end cover (2) are connected on all sides, a receiving cavity (5) is formed inside the metal spherical shell (1) by 3D printing, a circle of second convex edges (6) are provided at the bottom of the receiving cavity (5), the sensor component is arranged in the second convex edges (6) and is mutually constrained with the second convex edges (6), and a group of annular cavities (7) that are not connected to the receiving cavity (5) are provided at the bottom of the metal spherical shell (1).

2. According to claim 1, a spherical underwater acoustic transducer based on 3D metal printing is characterized in that: The sensing components include: A group of intermediate mass blocks (8), a piezoelectric ceramic stack (9) is pressed between the intermediate mass blocks (8), third convex edges (10) are arranged on both sides of the intermediate mass blocks (8), and the piezoelectric ceramic stack (9) is arranged inside the third convex edge (10) and is mutually constrained with the third convex edge (10); Piezoelectric ceramic stacks (9), each piezoelectric ceramic stack (9) is composed of a plurality of piezoelectric ceramic sheets (11), and the piezoelectric ceramic sheets (11) are made of piezoelectric ceramic material; A conductor copper sheet (12), the conductor copper sheet (12) is arranged on the piezoelectric ceramic stack (9), and leads (13) are arranged on both sides of the conductor copper sheet (12).

3. According to claim 2, a spherical underwater acoustic transducer based on 3D metal printing is characterized in that: A group of openings (4) are provided on the upper end cover (2), and the lead wires (13) pass through the openings (4).

4. According to the 3D metal printing-based spherical underwater acoustic transducer of claim 1, it is characterized in that: The metal spherical shell (1) and the upper end cover (2) are sealed by epoxy resin glue.

5. The spherical underwater acoustic transducer based on 3D metal printing according to claim 1, characterized in that: The accommodating cavity (5) is in a water drop shape.

6. The spherical underwater acoustic transducer based on 3D metal printing according to claim 1, characterized in that: The annular cavity (7) is tightly connected to the metal spherical shell (1) by means of 3D metal printing or aluminum welding.

7. The spherical underwater acoustic transducer based on 3D metal printing according to claim 1, characterized in that: The metal material in the metal spherical shell (1) is aluminum.

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