A closed-cavity PVDF film loudspeaker

Abstract

The invention proposes a closed cavity type PVDF thin-film loudspeaker. The closed cavity type PVDF thin-film loudspeaker comprises a main structure and an impedance converter; the main structure comprises a PVD thin film, a sound absorbing material layer and a glass fiber reinforced plastics back cavity; the PVDF thin film has double-sided electrodes; the double-sided electrodes respectively leadout external electrodes; the PVDF thin film and the double-sided electrodes are subjected to insulation encapsulation, and parts of the external electrodes are exposed during the insulation encapsulation; an open surface of the glass fiber reinforced plastics back cavity is a cambered surface with a rectangular projection, and the PVDF thin film after being subjected to the insulation encapsulation is sealed and fixedly connected with the edge of the open surface of the glass fiber reinforced plastics back cavity through a sealant; the sound absorbing material layer is fixed inside the glassfiber reinforced plastics back cavity body, and the sound absorbing material layer is not in contact with the PVDF thin film; and the main structure is connected with an external standard power amplifier through the impedance converter. The closed cavity type PVDF thin-film loudspeaker provided by the invention can effectively improve the sound radiation efficiency of the PVDF thin-film loudspeaker and reduce the sound radiation behind the PVDF thin-film loudspeaker, so as to solve the problems of the driving difficulty of the PVDF thin-film loudspeaker, the poor low frequency effect and the noise pollution behind the loudspeaker.

Description

technical field [0001] The invention belongs to the field of loudspeaker equipment and a design method thereof, in particular to a closed-cavity PVDF film loudspeaker. Background technique [0002] PVDF piezoelectric film material has good water resistance, corrosion resistance and impact resistance. The speaker supported by PVDF piezoelectric film has the advantages of bendability, flat appearance and light weight. Compared with traditional piezoelectric ceramic materials, it has a wider frequency response range, lower acoustic impedance and higher dielectric constant. [0003] Korean published patent 10-2007-0025543 discloses a PVDF piezoelectric film. In this patent, the PVDF film adopts a rectangular structure, and uniform carbon nanotube materials are first coated on both sides of the film, and then grid-type or frame-type are printed. Conductive silver gel electrode structure. The low-frequency effect of the PVDF loudspeaker example in this patent is not ideal enough...

AI Technical Summary

Problems solved by technology

In view of the above shortcomings of the existing film speakers, this paper proposes a closed-cavity PVDF film speaker, which can effectively improve the sound radiation efficiency of the PVDF film speaker and reduce the sound radiation behind the PVDF film speaker to improve the driving difficulties of the PVDF film speaker. The problem of poor low-frequency effect and noise pollution behind the speaker, and the problem of reverberation after adding a back cavity can also be solved by the design of the present invention

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