# US 2019/0320262 A1 · Electroacoustic transducer and electroacoustic transducer apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0320262 A1 - Document ID: US20190320262A1 - Status: Published application - Kind: A1 - Application number: 16/343,543 - Filed: 2017-10-25 - Published: 2019-10-17 - Earliest claimed: 2016-10-28 - Assignees: Sony Corporation - Applicants: Sony Corporation - Inventors: Toshiyuki Nakagawa; Yoshio Ohashi - Web page: https://patentgrep.com/patent/US20190320262A1 ## CPC - H04R 3/007: {Protection circuits for transducers} - H04R 7/125: {comprising a plurality of superposed layers in contact} - H04R 3/04: for correcting frequency response - H04R 3/12: for distributing signals to two or more loudspeakers {(specially adapted for hearing aids H04R25/407)} - H04R 7/10: comprising superposed layers in contact - H04R 17/00: Piezoelectric transducers; Electrostrictive transducers (piezoelectric or electrostrictive elements in general H10N30/00; details of piezoelectric or electrostrictive motors, generators or positioners {H10N30/00}) - H04R 31/003: {for diaphragms or their outer suspension} - H04R 7/127: {dome-shaped} - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) ## Abstract The present technology relates to an electroacoustic transducer and an electroacoustic transducer apparatus that are compact, have good characteristics, and can retain their stable shape. The electroacoustic transducer includes: a first sheet including a sheet-like piezoelectric material and having a curved shape; and a second sheet having substantially the same shape as the first sheet and placed on the first sheet in a layered manner. The present technology can be applied to an electroacoustic transducer. ## Claims ### Claim 1 An electroacoustic transducer comprising: a first sheet including a sheet-like piezoelectric material and having a curved shape; and a second sheet having substantially a same shape as the first sheet and placed on the first sheet in a layered manner. ### Claim 2 (depends on 1) The electroacoustic transducer according to claim 1, wherein the second sheet is a nonwoven fabric. ### Claim 3 (depends on 2) The electroacoustic transducer according to claim 2, further comprising a third sheet including a sheet-like piezoelectric material, having substantially a same shape as the first sheet, and placed in a layered manner on an opposite side of the second sheet that is not in contact with the first sheet. ### Claim 4 (depends on 1) The electroacoustic transducer according to claim 1, wherein the second sheet includes a piezoelectric material. ### Claim 5 (depends on 1) The electroacoustic transducer according to claim 1, wherein the second sheet is bonded to the first sheet. ### Claim 6 (depends on 1) The electroacoustic transducer according to claim 1, wherein the first sheet and the second sheet are fixed by sandwiching and pressing a press portion provided at an end portion of the first sheet and the second sheet between a frame fixing member and a frame base. ### Claim 7 (depends on 6) The electroacoustic transducer according to claim 6, wherein the frame fixing member and the frame base include opening portions for exposing the first sheet and the second sheet. ### Claim 8 (depends on 7) The electroacoustic transducer according to claim 7, wherein a tapered portion is formed on at least one of the frame fixing member or the frame base such that the opening portion has varying widths in a first direction in which the frame fixing member and the frame base are aligned when viewed from a second direction substantially perpendicular to the first direction. ### Claim 9 (depends on 8) The electroacoustic transducer according to claim 8, wherein the tapered portion is formed such that the opening portion becomes wider toward a position farthest from the first sheet and the second sheet in the first direction. ### Claim 10 (depends on 8) The electroacoustic transducer according to claim 8, wherein the tapered portion is formed such that the opening portion becomes narrower toward a position farthest from the first sheet and the second sheet in the first direction. ### Claim 11 An electroacoustic transducer apparatus comprising: a first electroacoustic transducer having: a first sheet having a curved shape and including a sheet-like piezoelectric material; and a second sheet having substantially a same shape as the first sheet and placed on the first sheet in a layered manner; and a second electroacoustic transducer having a third sheet including a sheet-like piezoelectric material, having a curved shape, and having an area different from an area of the first sheet of the second sheet. ### Claim 12 (depends on 11) The electroacoustic transducer apparatus according to claim 11, wherein the first electroacoustic transducer or the second electroacoustic transducer is a low-frequency electroacoustic transducer, and a protection adjustment unit is connected to the low-frequency electroacoustic transducer to protect the low-frequency electroacoustic transducer and adjust frequency characteristics. ### Claim 13 (depends on 12) The electroacoustic transducer apparatus according to claim 12, wherein the protection adjustment unit is a protection resistor or a low-pass filter. ### Claim 14 An electroacoustic transducer apparatus comprising: a first electroacoustic transducer having: a first sheet having a curved shape and including a sheet-like piezoelectric material; and a second sheet having substantially a same shape as the first sheet and placed on the first sheet in a layered manner; and a second electroacoustic transducer having: a third sheet having a curved shape and including a sheet-like piezoelectric material; and a fourth sheet having substantially a same shape as the third sheet and placed on the third sheet in a layered manner, the third sheet and the fourth sheet having an area different from an area of the first sheet and the second sheet.