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CN-121985272-A - Electroacoustic device structure with high sound pressure level

CN121985272ACN 121985272 ACN121985272 ACN 121985272ACN-121985272-A

Abstract

The invention relates to the technical field of piezoelectric ceramic sounding structures, in particular to a high sound pressure level electroacoustic device structure which comprises a shell and a piezoelectric vibrator, wherein the shell comprises an upper sounding cavity and a lower cover, the upper sounding cavity and the lower cover are assembled to form the shell, the piezoelectric vibrator is contained and installed in an inner cavity of the shell, a plurality of sound amplifying holes penetrating into the inner cavity are formed in the surface of the upper sounding cavity, the aperture ratio of the upper sounding cavity is at least 50%, the structure of the piezoelectric vibrator comprises a piezoelectric ceramic sheet and a metal vibrating diaphragm substrate, the piezoelectric ceramic sheet is adhered to one side or two sides of the metal vibrating diaphragm substrate, the sound pressure level of the electroacoustic device structure is higher, the sound pressure level of the device can be more than 100 db under the range of high frequency 15-50kHz, and the sound pressure level of the electroacoustic device can be up to 110db under the frequency of 30 kHz.

Inventors

  • QIU JUN
  • ZHANG XIUQIN

Assignees

  • 江苏波速传感器有限公司

Dates

Publication Date
20260505
Application Date
20251010

Claims (6)

  1. 1. The high sound pressure level electroacoustic device structure is characterized by comprising a shell and a piezoelectric vibrator, wherein the shell comprises an upper sounding cavity and a lower cover, the upper sounding cavity and the lower cover are assembled to form the shell, the piezoelectric vibrator is contained and installed in an inner cavity of the shell, a plurality of sound amplifying holes penetrating into the inner cavity are formed in the surface of the upper sounding cavity, the aperture ratio of the upper sounding cavity is at least 50%, and the diameter of the sound amplifying holes is 0.5-1.5mm; The structure of the piezoelectric vibrator comprises a piezoelectric ceramic sheet and a metal vibrating diaphragm substrate, wherein the piezoelectric ceramic sheet is adhered to one side or two sides of the metal vibrating diaphragm substrate, and the material of the piezoelectric ceramic sheet has the stoichiometric formula of ：[Pb a Na 0.01 Sr 0.03- 0.04 Ca 0.03-0.04 La 0.03-0.04 ][(Zr 0.55-0.6 Ti 0.4-0.45 ) b Mn 0.015-0.02 Sb 0.01 Nb 0.01 Sn 0.01 ]O 3 ; Wherein a takes the value of 0.85-0.9, and b takes the value of 0.95-0.99.
  2. 2. The structure of claim 1, wherein the piezoelectric ceramic plate is made of a material having a stoichiometric formula: [Pb 0.89 Na 0.01 Sr 0.034 Ca 0.033 La 0.033 ][(Zr 0.55 Ti 0.45 ) 0.952 Mn 0.018 Sb 0.01 Nb 0.01 Sn 0.01 ]O 3 .
  3. 3. the high sound pressure level electroacoustic device structure of claim 2, wherein the piezoelectric ceramic sheet is a single-layer piezoelectric sheet or a multi-layer piezoelectric sheet, the thickness of the piezoelectric ceramic sheet is 0.1-0.3mm, the diameter of the piezoelectric ceramic sheet is 20-30mm, and a silver conductive layer is arranged on the surface of the piezoelectric ceramic sheet.
  4. 4. The structure of claim 3, wherein the piezoelectric ceramic plates are adhered to two surfaces of the metal diaphragm substrate through adhesive layers, the thickness of the adhesive layers is controlled to be 2-8 micrometers, the adhesive layers are made of polyimide adhesive, and the metal diaphragm substrate can be made of one of copper and stainless steel.
  5. 5. The structure of any one of claims 1 to 4, wherein the diameter of the metal diaphragm substrate is larger than the diameter of the piezoelectric ceramic plate but smaller than the diameter of the internal cavity, the thickness of the metal diaphragm substrate is 0.1-0.2mm, and the thickness of the whole structure of the electroacoustic device is 4-6mm.
  6. 6. The structure of any one of claims 1-4, wherein the lower cover is mounted in a snap-fit manner to the upper sound-producing cavity, and the upper sound-producing cavity has a mounting portion that is fixedly secured to the lower cover after the snap-fit manner; The piezoelectric vibrator is provided with a lead wire connected with the anode and the cathode of an external power supply; The upper sounding cavity is provided with a step surface which extends outwards for 0.1-2mm in thickness, the diameter of the step surface is 60% -90% of the diameter of the upper sounding cavity, and the sound amplifying hole is positioned on the step surface; The side of the shell is provided with a lead wire outlet.

Description

Electroacoustic device structure with high sound pressure level Technical Field The invention relates to the technical field of piezoelectric ceramic sounding structures, in particular to a high-sound-pressure-level electroacoustic device structure. Background The piezoelectric ceramic electroacoustic device can effectively convert mechanical energy and electric energy, and is widely applied to the fields of communication equipment, security systems, medical instruments, instruments and meters, industrial automatic control, household appliances and the like. The piezoelectric material is an important functional material capable of realizing the mutual conversion of mechanical energy and electric energy, and lead zirconate titanate (PZT) based piezoelectric ceramics are widely used for electronic components such as sensors, drivers, ultrasonic transducers, filters, buzzers, loudspeakers and the like due to the excellent dielectric property and piezoelectric property. The piezoelectric loudspeaker is a device for sounding by utilizing the inverse piezoelectric effect, when the voltage signal is applied to the electrode on the piezoelectric ceramic plate, the ceramic plate can generate telescopic deformation, the ceramic plate and the vibrating diaphragm are bonded together, the vibrating diaphragm is driven by the ceramic plate to vibrate, and then air vibration is pushed to generate sound pressure to make sound. Compared with the traditional electroacoustic device, the piezoelectric loudspeaker has the advantages of light and thin appearance, small required sound cavity, good heat dissipation, long service life, no magnetic field, no electromagnetic radiation and the like. Along with the extension of application scenes to the requirements of high frequency and high fidelity, the traditional single-sided piezoelectric ceramic electroacoustic device gradually exposes the problems of insufficient sound pressure level, narrow frequency response range, low energy conversion efficiency and the like. Disclosure of Invention In order to solve the technical problem that the sound pressure level of the existing piezoelectric electroacoustic structure is low, a high sound pressure level electroacoustic device structure is provided. The electroacoustic device structure has higher sound pressure level, the sound pressure level of the electroacoustic device can reach more than 100 db under the high-frequency 15-50kHz range, the sound pressure level of the electroacoustic device reaches 120db under the frequency of 18kHz, and the sound pressure level of the electroacoustic device reaches 110db under the frequency of 30 kHz. In order to achieve the above purpose, the invention is realized by the following technical scheme: The high sound pressure level electroacoustic device structure comprises a shell and a piezoelectric vibrator, wherein the shell comprises an upper sounding cavity and a lower cover, the upper sounding cavity and the lower cover are assembled to form the shell, the piezoelectric vibrator is contained and installed in an inner cavity of the shell, a plurality of sound amplifying holes penetrating into the inner cavity are formed in the surface of the upper sounding cavity, the aperture ratio of the upper sounding cavity is at least 50%, and the diameter of the sound amplifying holes is 0.5-1.5mm; The piezoelectric vibrator structurally comprises a piezoelectric ceramic piece and a metal vibrating diaphragm substrate, wherein the piezoelectric ceramic piece is adhered to one side or two sides of the metal vibrating diaphragm substrate, the stoichiometric formula of the piezoelectric ceramic piece is ：[PbaNa0.01Sr0.03-0.04Ca0.03-0.04La0.03-0.04][(Zr0.55-0.6Ti0.4-0.45)bMn0.015-0.02Sb0.01Nb0.01Sn0.01]O3;, wherein a takes a value in the range of 0.85-0.9, and b takes a value in the range of 0.95-0.99. Further, the material of the piezoelectric ceramic sheet has a stoichiometric formula [Pb0.89Na0.01Sr0.034Ca0.033La0.033][(Zr0.55Ti0.45)0.952Mn0.018Sb0.01Nb0.01Sn0.01]O3. and a preparation method thereof is described in application No. 2025107513942. Still further, the piezoelectric ceramic sheet is a single-layer piezoelectric sheet or a multi-layer piezoelectric sheet, the thickness of the piezoelectric ceramic sheet is 0.1-0.3mm, the diameter of the piezoelectric ceramic sheet is 20-30mm, and the surface of the piezoelectric ceramic sheet is provided with a silver conductive layer. Still further, the piezoelectric ceramic plate is adhered to two surfaces of the metal diaphragm substrate through an adhesive layer, the thickness of the adhesive layer is controlled to be 2-8 micrometers, the adhesive layer is made of polyimide adhesive, and the metal diaphragm substrate can be made of one of copper and stainless steel. The high-frequency vibration of the device is easy to cause the ageing of the bonding layer, and the polyimide adhesive has better fatigue resistance. In addition, the single-layer piezoelectric she