# US 10,455,305 B2 · Electroacoustic transducer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,455,305 B2 - Document ID: US10455305B2 - Status: Granted - Kind: B2 - Application number: 16/026,392 - Filed: 2018-07-03 - Published: 2018-11-01 - Granted: 2019-10-22 - Earliest claimed: 2016-01-19 - Assignees: FUJIFILM Corporation - Applicants: FUJIFILM Corporation - Inventors: Tetsu Miyoshi - Web page: https://patentgrep.com/patent/US10455305B2 ## CPC - G10K 11/17885: {additionally using a desired external signal, e.g. pass-through audio such as music or speech} - A47G 9/1045: {shaped as, combined with, or convertible into other articles, e.g. dolls, sound equipments, bags or the like} - G10K 9/122: using piezoelectric driving means {(G10K9/121 takes precedence)} - G10K 9/22: Mountings; Casings - G10K 11/17857: {Geometric disposition, e.g. placement of microphones} - G10K 11/17881: {the reference signal being an acoustic signal, e.g. recorded with a microphone} - H04R 1/02: Casings; Cabinets {; Supports therefor;} Mountings therein (H04R1/28 takes precedence {; attachments for microphones H04R1/08; mounting of transducers in earpieces H04R1/1075}) - H04R 1/025: {Arrangements for fixing loudspeaker transducers, e.g. in a box, furniture} - H04R 1/2869: {Reduction of undesired resonances, i.e. standing waves within enclosure, or of undesired vibrations, i.e. of the enclosure itself} - H04R 5/023: {in a chair, pillow} - H04R 7/04: Plane diaphragms - 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 17/10: Resonant transducers, i.e. adapted to produce maximum output at a predetermined frequency - H04R 31/00: Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor {(manufacture of microstructural arrangements of deformable or non-deformable structures in general B81C1/00182)} - H10N 30/852: {Composite materials, e.g. having 1-3 or 2-2 type connectivity} - A47G 2009/006: {comprising sound equipment} - G10K 2210/108: Communication systems, e.g. where useful sound is kept and noise is cancelled - G10K 2210/3212: Actuator details, e.g. composition or microstructure - G10K 2210/3221: Headrests, seats or the like, for personal ANC systems - H04R 17/005: {using a piezoelectric polymer} - G10K: SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR - A47G: HOUSEHOLD OR TABLE EQUIPMENT (book-ends A47B5/00; knives B26B) - 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) - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR ## Abstract Provided is an electroacoustic transducer capable of reducing the thickness and weight of the entire pillow when a speaker is embedded in the pillow or a headrest, enabling miniaturization of a device by causing the position of the speaker to be close to a position at which the head is placed, and improving the accuracy of signal processing by reducing a load of the signal processing in a case where active noise control is performed, thereby improving a noise reduction effect. The electroacoustic transducer includes: an electroacoustic transduction unit having an electroacoustic transduction film including a polymer composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material having viscoelasticity at a normal temperature and thin film electrodes respectively laminated on both surfaces of the polymer composite piezoelectric body, and an elastic support disposed in close contact with one principal surface to bend the shape of the electroacoustic transduction film; and a first cushion layer that is in contact with the electroacoustic transduction film on an electroacoustic transduction film side of the electroacoustic transduction unit to cover the electroacoustic transduction unit and is formed of a three-dimensional solid knitted fabric. ## Claims ### Claim 1 An electroacoustic transducer comprising: an electroacoustic transduction unit having an electroacoustic transduction film including a polymer composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material having viscoelasticity at a normal temperature and thin film electrodes respectively laminated on both surfaces of the polymer composite piezoelectric body, and an elastic support disposed in close contact with one principal surface of the electroacoustic transduction film to bend the shape of the electroacoustic transduction film; and a first cushion layer that is in contact with the electroacoustic transduction film on an electroacoustic transduction film side of one or more electroacoustic transduction units to cover the one or more electroacoustic transduction units and is formed of a three-dimensional solid knitted fabric. ### Claim 2 (depends on 1) The electroacoustic transducer according to claim 1, wherein two electroacoustic transduction units are provided, and the two electroacoustic transduction units are disposed at positions symmetric with respect to a center line of a principal surface of the first cushion layer. ### Claim 3 (depends on 1) The electroacoustic transducer according to claim 1, further comprising: a second cushion layer which covers the electroacoustic transduction unit on a surface of the electroacoustic transduction unit, the surface being opposite to the electroacoustic transduction film. ### Claim 4 (depends on 2) The electroacoustic transducer according to claim 2, further comprising: a second cushion layer which covers the electroacoustic transduction unit on a surface of the electroacoustic transduction unit, the surface being opposite to the electroacoustic transduction film. ### Claim 5 (depends on 1) The electroacoustic transducer according to claim 1, wherein the first cushion layer is in contact with the electroacoustic transduction film. ### Claim 6 (depends on 4) The electroacoustic transducer according to claim 4, wherein the first cushion layer is in contact with the electroacoustic transduction film. ### Claim 7 (depends on 1) The electroacoustic transducer according to claim 1, wherein a forming material of the first cushion layer is polyester or nylon. ### Claim 8 (depends on 6) The electroacoustic transducer according to claim 6, wherein a forming material of the first cushion layer is polyester or nylon. ### Claim 9 (depends on 1) The electroacoustic transducer according to claim 1, wherein a thickness of the first cushion layer is 3 mm to 30 mm. ### Claim 10 (depends on 8) The electroacoustic transducer according to claim 8, wherein a thickness of the first cushion layer is 3 mm to 30 mm. ### Claim 11 (depends on 1) The electroacoustic transducer according to claim 1, wherein the second cushion layer is any one of an integral molded product of urethane foam, wadding of inelastic crimped fibers, and a fiber-based cushion obtained by bonding inelastic crimped fibers with a binder. ### Claim 12 (depends on 10) The electroacoustic transducer according to claim 10, wherein the second cushion layer is any one of an integral molded product of urethane foam, wadding of inelastic crimped fibers, and a fiber-based cushion obtained by bonding inelastic crimped fibers with a binder. ### Claim 13 (depends on 1) The electroacoustic transducer according to claim 1, further comprising: a microphone disposed in the first cushion layer, wherein the microphone is disposed at a position overlapping the electroacoustic transduction unit in a surface direction of a principal surface of the first cushion layer. ### Claim 14 (depends on 12) The electroacoustic transducer according to claim 12, further comprising: a microphone disposed in the first cushion layer, wherein the microphone is disposed at a position overlapping the electroacoustic transduction unit in a surface direction of a principal surface of the first cushion layer. ### Claim 15 (depends on 13) The electroacoustic transducer according to claim 13, wherein the electroacoustic transduction unit functions as a speaker which reproduces a noise cancelling signal generated on the basis of a noise signal detected by the microphone. ### Claim 16 (depends on 14) The electroacoustic transducer according to claim 14, wherein the electroacoustic transduction unit functions as a speaker which reproduces a noise cancelling signal generated on the basis of a noise signal detected by the microphone. ### Claim 17 (depends on 1) The electroacoustic transducer according to claim 1, wherein the elastic support is a viscoelastic support having viscoelasticity. ### Claim 18 (depends on 1) The electroacoustic transducer according to claim 1, wherein a curvature of a bent portion of the electroacoustic transduction film changes from a center toward a peripheral portion. ### Claim 19 (depends on 1) The electroacoustic transducer according to claim 1, wherein a shape of the bent portion when viewed in a direction perpendicular to the principal surface of the electroacoustic transduction film is a polygonal shape or a circular shape.