ClassID:

232136

H04R2209/022 - CPC Classification

Classification description:

Details of transducers of the moving-coil, moving-strip, or moving-wire type covered by but not provided for in any of its subgroups Aspects regarding the stray flux internal or external to the magnetic circuit, e.g. shielding, shape of magnetic circuit, flux compensation coils

Recent Application in this class:
#1
20260156417
2026-06-04

ACOUSTIC ELECTRODYNAMIC ACTUATOR WITH STRUCTURED END FACE OF OUTER MAGNETIC CIRCUIT PART AND OUTPUT DEVICE THERETO

#2
20260129370
2026-05-07

DIAPHRAGMS, AIR CONDUCTION SPEAKERS, AND WEARABLE ELECTRONIC DEVICES

#3
20260129368
2026-05-07

DIAPHRAGMS, AIR CONDUCTION SPEAKERS, AND WEARABLE ELECTRONIC DEVICES

#4
20260129324
2026-05-07

LOUDSPEAKERS AND ELECTRONIC DEVICES

#5
20260082167
2026-03-19

SPEAKER

#6
20260012726
2026-01-08

EAR-CLIP EARPHONES

#7
20250386146
2025-12-18

Acoustic electromagnetic actuator with high magnetic flux density in outer magnetic circuit part and output device thereto

#8
20250294294
2025-09-18

VIBRATION TRANSMISSION SHEETS, BONE-CONDUCTING LOUDSPEAKERS, AND EARPHONES

#9
20250280241
2025-09-04

EARPHONES

#10
20250280226
2025-09-04

EARPHONES

#11
20250254480
2025-08-07

ELECTROMAGNETIC TRANSDUCER WITH SPECIFIC INTERNAL GEOMETRY

#12
20250193608
2025-06-12

HYBRID SOUND RADIATION DEVICE FOR VIBRATING A HEAVY-WEIGHT RIGID PLATE AT AUDIO FREQUENCIES

#13
20250175726
2025-05-29

LOUDSPEAKERS AND ELECTRONIC DEVICES

#14
20250159413
2025-05-15

LOUDSPEAKERS AND ELECTRONIC DEVICES

#15
20250133347
2025-04-24

SPEAKER DEVICE

#16
20240348980
2024-10-17

Double-sided Sounding Device

#17
20240323623
2024-09-26

MAGNETIC RETENTION SYSTEM

#18
20240251205
2024-07-25

Audio Transducer With Forced Ventilation of Motor and Method

#19
20230372971
2023-11-23

ELECTRODYNAMIC VIBRATION EXCITER

#20
20230199394
2023-06-22

Audio transducer with forced ventilation of motor and method

#21
20230156416
2023-05-18

Magnetic retention system

#22
20230128831
2023-04-27

Loudspeaker and electronic apparatus

#23
20230117602
2023-04-20

IMPROVEMENTS IN AND RELATING TO LOUDSPEAKER MAGNET ASSEMBLIES

#24
20230007376
2023-01-05

Audio device transducer and associated systems and methods

#25
20220345824
2022-10-27

Sound-producing apparatus, acoustic module provided with sound-producing apparatus, and electronic device

#26
20220312123
2022-09-29

Speaker

#27
20220021991
2022-01-20

BONE CONDUCTION MAGNETIC RETENTION SYSTEM

#28
20210360358
2021-11-18

Electromagnetic transducer with specific internal geometry

#29
20210352410
2021-11-11

Audio transducer with forced ventilation of motor and method

#30
20210306776
2021-09-30

Bone conduction device including a balanced electromagnetic actuator having radial and axial air gaps

#31
20210127211
2021-04-29

Electro-magnetic motor geometry with radial ring and axial pole magnet

#32
20200404426
2020-12-24

Loudspeaker assembly, sound generating apparatus and electronic device

#33
20200404425
2020-12-24

Sound generator and electronic product

#34
20200382857
2020-12-03

Wearable audio device

#35
20200275212
2020-08-27

Loudspeaker

#36
20190313193
2019-10-10

Loudspeaker with dual plate structure

#37
20190268688
2019-08-29

Hybrid speaker

#38
20190246210
2019-08-08

Magnet assembly for a loudspeaker and loudspeaker with such a magnet assembly

#39
20190230443
2019-07-25

Electric motor

#40
20190215625
2019-07-11

Bone conduction device including a balanced electromagnetic actuator having radial and axial air gaps

#41
20190182598
2019-06-13

Electric motor

#42
20190141461
2019-05-09

Bone conduction magnetic retention system

#43
20190141454
2019-05-09

Sound Transducer

#44
20190098412
2019-03-28

Dome tweeter

#45
20190037317
2019-01-31

Transducer and method of operation

#46
20180235112
2018-08-16

Magnetic field shielding apparatus

#47
20180070482
2018-03-08

Electronic device having structure for shielding magnetic force

#48
20180070182
2018-03-08

Electric motor

#49
20180063643
2018-03-01

Loudspeaker structure

#50
20180035188
2018-02-01

Electronic device with speaker

#51
20180007470
2018-01-04

Loudspeaker

#52
20170325035
2017-11-09

Electromagnetic transducer with specific internal geometry

#53
20170230755
2017-08-10

Loudspeaker magnetic circuit and loudspeaker equipped with same

#54
20170134864
2017-05-11

Method of manufacturing a sound transducer

#55
20170104262
2017-04-13

Transmitter with improved sensitivity and shielding

#56
20170070831
2017-03-09

Bone conduction device including a balanced electromagnetic actuator having radial and axial air gaps

#57
20170041714
2017-02-09

Transducer

#58
20170034628
2017-02-02

Speaker

#59
20170034627
2017-02-02

Speaker

#60
20160381481
2016-12-29

Speaker

#61
20160277841
2016-09-22

Magnetic shielding and communication coil

#62
20160277819
2016-09-22

One piece frame for a component in an electronic device

#63
20160269829
2016-09-15

Speaker apparatus

#64
20160261958
2016-09-08

Electromagnetic signal converter for an osteophone

#65
20160225362
2016-08-04

Acoustic device

#66
20160219376
2016-07-28

MEMS microphone package

#67
20160219371
2016-07-28

Loudspeaker

#68
20160150322
2016-05-26

Acoustic transducer assembly

#69
20160142809
2016-05-19

Wiring structure for electroacoustic transducer for digital signal and headphone for digital signal

#70
20160127833
2016-05-05

Speaker control device

#71
20160112805
2016-04-21

Transducer and method of operation

#72
20160057541
2016-02-25

Moving coil motor arrangement with a sound outlet for reducing magnetic particle ingress in transducers

#73
20160037273
2016-02-04

Bone conduction magnetic retention system

#74
20160029127
2016-01-28

Speaker apparatus

#75
20150380821
2015-12-31

Transmitter with improved sensitivity and shielding

#76
20150350757
2015-12-03

Speaker structure

#77
20150326975
2015-11-12

Voice coil speaker

#78
20150222998
2015-08-06

Bone conduction device including a balanced electromagnetic actuator having radial and axial air gaps

#79
20150172820
2015-06-18

Transducer and method of operation

#80
20150117698
2015-04-30

Low profile loudspeaker transducer

#81
20150086066
2015-03-26

Electro-acoustic transducer

#82
20150078612
2015-03-19

STRUCTURE OF SPEAKER DRIVER

#83
20150078610
2015-03-19

Electrodynamic loudspeaker with conducting elements

#84
20150016659
2015-01-15

Miniature electroacoustic transducer and assembling method thereof

#85
20150010198
2015-01-08

Acoustic transducer

#86
20140355812
2014-12-04

Shielded audio apparatus

#87
20140294228
2014-10-02

Loudspeaker magnetic circuit and loudspeaker using same

#88
20140275731
2014-09-18

Electromagnetic transducer with specific internal geometry

#89
20140270297
2014-09-18

Electromagnetic transducer with air gap substitute

#90
20140238737
2014-08-28

Reducing inductive heating

#91
20140226849
2014-08-14

Long-throw acoustic transducer

#92
20140205135
2014-07-24

Loudspeaker and equipment including the same

#93
20140146993
2014-05-29

Dust protection of sound transducer

#94
20140087659
2014-03-27

Transmitter with improved sensitivity and shielding

#95
20140056467
2014-02-27

Loudspeaker and electronic equipment including the loudspeaker

#96
20140056448
2014-02-27

Magnetic shielding apparatus

#97
20130329910
2013-12-12

Systems and methods for reducing stray magnetic flux

#98
20130328648
2013-12-12

Magnetic shielding apparatus

#99
20130202140
2013-08-08

Bone conduction device including a balanced electromagnetic actuator having radial and axial air gaps

#100
20130170674
2013-07-04

Moving iron unit for loudspeakers

#101
20130108099
2013-05-02

LOUDSPEAKER HAVING IMPROVED COOLING SYSTEM INTEGRALLY FORMED ON SPEAKER FRAME

#102
20130108085
2013-05-02

Low profile loudspeaker

#103
20130083957
2013-04-04

Dust protection of sound transducer

#104
20130077816
2013-03-28

Inductive electroacoustic transducer

#105
20130064406
2013-03-14

RF shielding for acoustic devices

#106
20130058519
2013-03-07

Low rise speaker assembly having a dual voice coil driver

#107
20120237067
2012-09-20

Bone conduction device including a balanced electromagnetic actuator having radial and axial air gaps

#108
20120155699
2012-06-21

SPEAKER AND YOKE THEREOF

#109
20120114166
2012-05-10

Speaker and electronic apparatus and device using the same

#110
20120087523
2012-04-12

Speaker having center pleat

#111
20120051581
2012-03-01

Split magnet loudspeaker

#112
20110293127
2011-12-01

Unidirectional condenser microphone unit

#113
20110293117
2011-12-01

Boundary microphone

#114
20110286619
2011-11-24

Ribbon transducer with improved distortion characteristics

#115
20110182462
2011-07-28

ELECTROMAGNETICALLY-SHIELDED SPEAKER SYSTEMS AND METHODS

#116
20110116664
2011-05-19

MAGNETOSTRICTIVE ACTUATOR AND SPEAKER AND DEVICE USING SAID MAGNETOSTRICTIVE ACTUATOR

#117
20110116662
2011-05-19

SPEAKER DEVICE

#118
20110110549
2011-05-12

Ironless and leakage free coil transducer motor assembly

#119
20110044491
2011-02-24

LONG EXCURSION LOUDSPEAKER WITH CLOSED MAGNETIC CIRCUIT AND RIBBED ROBBIN EXTENDING THROUGH SLOTTED YOKE

#120
20110007913
2011-01-13

MAGNET ASSEMBLY FOR A LOUDSPEAKER

#121
20100172534
2010-07-08

Magnetic structure for an ironless electrodynamic-loudspeaker motor, motors and loudspeakers

#122
20100080406
2010-04-01

Push-pull type speaker device and method of manufacturing the same

#123
20100027833
2010-02-04

SPEAKER UNIT

#124
20100021000
2010-01-28

Sound producing system

#125
20090304222
2009-12-10

Low cost motor design for rare-earth-magnet loudspeakers

#126
20090221327
2009-09-03

Audio Device

#127
20090220119
2009-09-03

SPEAKER, AND MODULE, ELECTRONIC APPARATUS, AND DEVICE THAT USE THE SPEAKER

#128
20090202100
2009-08-13

Voice coil and speaker

#129
20090161902
2009-06-25

Loudspeakers, systems and components thereof

#130
20090060254
2009-03-05

SPEAKER AND ELECTRONIC APPARATUS AND DEVICE USING THE SAME

#131
20090028375
2009-01-29

Electrodynamic transducer and use thereof in loudspeakers and geophones

#132
20080205690
2008-08-28

Loudspeaker magnetic flux collection system

#133
20080180201
2008-07-31

Magnetic circuit

#134
20080031487
2008-02-07

Electro-Acoustic Transducer And A Method For Assembly Thereof

#135
20080025552
2008-01-31

Magnetic circuit for speaker device and speaker device

#136
20070165902
2007-07-19

Electrodynamic electroacoustic transducer and electronic device

#137
20070147652
2007-06-28

Speaker device

#138
20070147649
2007-06-28

Speaker, and module, electronic apparatus, and device that use the speaker

#139
20070092093
2007-04-26

Electromagnetically-shielded speaker systems and methods

#140
20060239499
2006-10-26

Semi-radially-charged conical magnet for electromagnetic transducer

#141
20060239496
2006-10-26

Magnetically tapered air gap for electromagnetic transducer

#142
20060239492
2006-10-26

Loudspeakers, systems, and components thereof

#143
20060182304
2006-08-17

Speaker, module employing it, electronic apparatus and device

#144
20060177090
2006-08-10

Electro-acoustic transducer

#145
20060093180
2006-05-04

Magnetic circuit having dual magnets, speaker and vibration generating apparatus using the same

#146
20060025179
2006-02-02

External speaker for mobile phone for preventing malfunction of a mobile phone caused by a leakage magnetic field

#147
20060018495
2006-01-26

Radio frequency shielding for receivers within hearing aids and listening devices

#148
20050259842
2005-11-24

Gasket for reducing electromagnetic interference in a boundary microphone

#149
20050232456
2005-10-20

Loudspeaker, systems, and components thereof

#150
20050190946
2005-09-01

Dual-gap transducer with radially-charged magnet

#151
20050175213
2005-08-11

Electromagnetic transducer having a low reluctance return path

#152
20050129266
2005-06-16

Speaker device

#153
20050031154
2005-02-10

Electromagnetic transducer having multiple magnetic air gaps whose magnetic flux is in a same direction

#154
18135677
2025-11-04

Magnetic field cancelling audio devices

#155
17953542
2023-03-21

Electrodynamic actuator for acoustic oscillations

#156
17493824
2023-05-02

Magnetic field canceling audio devices

#157
16773952
2021-10-12

Magnetic field canceling audio devices

#158
15389126
2018-04-10

Electromagnetic transducer having paired Halbach arrays

#159
14451047
2015-09-08

Electromechanical transducer with non-circular voice coil

#160
14209517
2016-11-01

Dual ring magnet apparatus

#161
13719000
2014-10-07

Dual ring magnet apparatus