Abstract: A coaxial loudspeaker for reproducing an electrical sound signal is provided. The loudspeaker has a magnetic driver assembly with a first annular slot and an opposed, coaxial second annular slot, each establishing a permanent magnetic field therein from a single magnet. Independently driven first and second voice coils are positioned within the respective one of the first and second annular slots, each being connected to a transducer element.

Abstract: The present invention relates to a dynamic type unit with a multiple magnetic field system, and more particularly, to a dynamic type unit including a magnet, a diaphragm and a moving coil such as a microphone or a speaker, wherein an auxiliary magnet is mounted around a main magnetic field formed by the magnet so as to form an auxiliary magnetic field to thereby correct a waveform of each individual distorted frequency generated from the microphone or the speaker, which results in realization of the best sound whose quality is closest to that of an original sound.

Abstract: An audio speaker with at least two electric coils on opposite sides of at least one ferro-magnetic plate, the coils and plate forming a radial electro-magnet. A radial electro-magnet can offer many advantages in stereo loudspeakers. The coils are electrically driven in opposite directions. Multiple sets of two coils and intervening ferro-magnetic plate may be provided, adjacent sets being separated by a non-magnetic plate.

Abstract: An electro-acoustic transducer includes a diaphragm, a casing which is formed with an opening for directly or indirectly supporting the diaphragm, a first magnetic pole section provided on a side of the opening with respect to the diaphragm and having a magnetic pole at a surface which faces the diaphragm, a second magnetic pole section provided on a side of an inner bottom surface of the casing with respect to the diaphragm and having a magnetic pole at least a part of a surface which faces the first magnetic pole section through the diaphragm, and a drive coil provided on the diaphragm and located in a magnetic gap formed by the first and second magnetic pole sections. The magnetic poles of the first and second magnetic pole sections which face each other through the diaphragm have the same polarity. An outer shape of the surface of the first magnetic pole section which faces the diaphragm is smaller than that of the surface of the second magnetic pole section which faces the diaphragm.

Abstract: A speaker diaphragm is configured by a compound mixed with resin and bamboo fiber. The diaphragm satisfying the advantage of the bamboo fiber of high sound quality and a large degree of freedom in the setting of the characteristic value of the diaphragm and the advantage of the diaphragm made of a resin with improved humidity resistance reliability and strength, excellent external appearance, and enhanced productivity and dimension stability is obtained.

Abstract: The invention provides an electroacoustic transducer capable of efficiently carrying out conversion from electric signals to sound or from sound to electric signals at low distortion, which requires no special shape nor processing as a magnet, requires no minute setting of the magnetization direction, and sets a distribution of higher magnetic flux densities for effective action with respect to an electric conductor of an acoustic diaphragm than in a magnet plate magnetized in the radius direction although the production process thereof is remarkably simple as in a magnet plate magnetized in the radius direction.

Abstract: A magnetic structure generating a magnetic field for an ironless motor of an electrodynamic loudspeaker having a mobile coil, wherein the magnetic structure generates a magnetic field in a gap in which the coil is arranged. The magnetic structure includes of a stack of three magnets corresponding to one intermediate magnet and two top and bottom covering magnets, the magnets forming a straight gap border and being located side by side, the intermediate magnet having a radial magnetic polarization, the covering magnets having identical magnetic polarizations and remanent magnetizations. The covering magnets have a radial or axial magnetic polarization. When magnetic polarization of the covering magnets is radial, remanent magnetization of each covering magnet is higher than remanent magnetization of the intermediate magnet, and when magnetic polarization of the covering magnets is axial, remanent magnetization of each covering magnet is lower than remanent magnetization of the intermediate magnet.

Abstract: Provided are a microspeaker and a method of designing the same.

Abstract: A long and narrow loudspeaker on an entire wall gives off a cylindrical wave, which covers the entire room. Extra loudspeakers fixed at an angle against the wall will be heard in another direction, producing angle stereo independent of where one is in the room. Electro-dynamic loudspeakers are made of long plates of iron with air gapes between them where magnetic fields are produced. In the air gaps are strips, which conduct the sound currents. The strips influence directly one or more membranes. The magnetic field can be produced by permanent magnets, electromagnets or through concentration of geomagnetic fields. Long loudspeakers, which use other forces such as electrostatic forces, only need to be made for small sound pressure at the membrane.

Abstract: A speaker apparatus comprises: a drive cone transferring a drive power of a voice coil to the diaphragm; a diaphragm disposed in a driving direction; and a diaphragm disposed in a driving direction. The drive cone is fixed to a diaphragm support of a frame. An outer circumference of the diaphragm is fixed to the diaphragm support of the frame. An outer circumference of the diaphragm is fixed to the diaphragm support of the frame. The diaphragm, the drive cone and the frame surround a sealed space where the diaphragm and the drive cone are connected through a non-ring-shaped connection piece. A vibration system is supported through a voice coil bobbin by a spring property of air contained in the sealed space.

Abstract: A loudspeaker apparatus comprises a housing, an adsorptive material provided inside the housing, for physically adsorbing gas inside the housing, a vibration section including a diaphragm and provided in an opening formed in the housing, a drive section for driving the diaphragm to generate sound from the diaphragm, and a negative stiffness generating mechanism provided inside the housing, for reducing an acoustic stiffness inside the housing, the acoustic stiffness acting on the diaphragm.

Abstract: A planar diaphragm acoustic loudspeaker having a planar diaphragm biased with a high magnetic flux density magnetic circuit which feeds an acoustic waveguide. The apparatus provides high fidelity and efficient acoustic reproduction of high frequency alternating current signals with a minimum of diaphragm resonance and with a substantially flat electrical input impedance versus frequency. The diaphragm has a substantially uniform drive across an acoustically active portion and is held in three dimensional space whereby any mass or diaphragm resonances are controlled and minimized. The acoustic waveguide mates with said diaphragm and ensures a uniform acoustic phase field and an optimal diaphragm acoustic impedance match with atmosphere.

Abstract: An acoustic apparatus has permanent magnets 2 and 3, which have north poles and south poles magnetized alternately in a stripe-like fashion, at the front and back of a diaphragm 1, respectively; and has a conductor circuit 4 wired on the diaphragm 1 along the stripe-like poles of the permanent magnets 2 and 3. This offers an advantage of being able to prevent an echo. The diaphragm 1, permanent magnets 2 and 3, conductor circuit 4, spacer 5, and iron plates 6 and 7 are installed in a baffle 8.

Abstract: A magnet structure for use with a loudspeaker has an interlocking mechanism. The magnet structure can include a magnet, a shell pot and at least one core cap. The shell pot can contain the magnet in its hollow interior. The magnet can be a single magnet or double magnets. The core cap has two surfaces. For a single magnet, one surface of the core cap faces the magnet. For double magnets, the core cap can be vertically disposed between the two magnets. The magnet, the core cap and the shell pot can interlock with one another such that a position of the magnet relative to the core cap and the shell pot can be rigidly preserved. The magnet can be configured to be, for example, overlapped, inserted, staked and/or engaged with at least one of the shell pot or the core cap.

Abstract: An electrodynamic electroacoustic transducer comprises: a first magnetic pole; a second magnetic pole that forms a magnetic gap between itself and the first magnetic pole and is arranged in a space excluding spaces in upper and lower face directions of the first magnetic pole; a yoke; a diaphragm; and a voice coil. The yoke magnetically couples one magnetic pole face of the first magnetic pole with one magnetic pole face of the second magnetic pole so as to support them. The diaphragm is arranged in a space in an upper face direction of the first magnetic pole and in a space in a lower face direction of the second magnetic pole, while its outer periphery is supported by the yoke. The voice coil is arranged in the magnetic gap and adhered to the diaphragm. At least one of the first magnetic pole part and the second magnetic pole part includes a magnet.

Abstract: A speaker apparatus includes a speaker frame, an acoustic vibrating plate movably supported on the speaker frame, and a magnetic driver formed in the speaker frame for vibrating the acoustic vibrating plate. The magnetic driver is connected such that it may vibrate different portions of the acoustic vibrating plate independently. The acoustic vibrating plate of the speaker apparatus may vibrate with the same phase, thereby increasing sound pressure and improving acoustic efficiency.

Abstract: A speaker device that comprises a cabinet and a speaker unit. The speaker unit is attached to an opening portion formed in a front surface of the cabinet. The speaker unit has a back surface frame, a front surface frame, a first magnetic circuit, a second magnetic circuit, an edge, a damper, a diaphragm, a voice coil bobbin, and a voice coil. A non-magnet member which is a portion of the diaphragm, the first magnetic circuit, and the second magnetic circuit play a role as a negative stiffness mechanism to suppress an influence of an acoustic stiffness, thereby achieving a small-size speaker device capable of reproducing low-frequency sound.

Abstract: A voice-coil transducer includes two radially concentric magnets, a voice-coil located in the gap between the inner and outer magnets, and a diaphragm coupled to the voice-coil. An audio loudspeaker includes the voice-coil transducer with two radially concentric magnets, a voice-coil located within the gap between the inner and outer magnets, a diaphragm coupled to the voice-coil in order to create sounds from the voice-coil, and a chassis to support the magnets, voice-coil, and diaphragm.

Abstract: An electrodynamic loudspeaker 1 includes a magnetic circuit 10 and a vibrator 20. The magnetic circuit 10 includes a magnet 11 and poles 12 and 13 adhering to the magnet 11. The vibrator 20 includes a coil bobbin 21 and voice coils 22 and 23 wound around and fixed to a portion of the coil bobbin 21 facing the poles 12 and 13. A magnetic member 30 is fixed to the coil bobbin 21 of the vibrator 20 at a position spaced apart from the voice coils 22 and 23. The magnetic member 30 is fixed at a position on the coil bobbin 21 so as to extend over an area facing the magnet 11 of the magnetic circuit 10.

Abstract: An electro-dynamic loudspeaker includes a frame, a magnet and a diaphragm. The frame includes a body portion defining a magnet mounting surface as well as a plurality of protrusions extending from the magnet mounting surface. The magnet is magnetically attracted to the body portion of the frame. The magnet is restricted from movement along the magnet mounting surface by at least one protrusion. The diaphragm is spaced apart from the magnet and coupled to the frame.

Abstract: An electroacoustic transducer has a magnetic circuit unit including a plate-shaped yoke, first and second magnets juxtaposed on the yoke, and first and second top plates mounted on the respective tops of the first and second magnets. One end of the first magnet is magnetized to one of north and south poles. The other end of the first magnet is opposite in polarity to the one end. The second magnet is magnetized to polarities opposite to those of the first magnet. A magnetic gap is formed between the first and second top plates.

Abstract: Leakage flux is reduced particularly in a magnetic gap of a magnetic circuit to improve the sensitivity of a dynamic microphone. A dynamic microphone including a magnetic circuit unit 20 including a center pole piece 22 connected to one pole of a first permanent magnet 21 and a yoke 23 which is connected to the other pole of the first permanent magnet 21 and is arranged like a ring around the center pole piece 22 via a magnetic gap of a predetermined width, a diaphragm 10 having voice coils 13 disposed in the magnetic gap, and a resonator 40 which has a front acoustic terminal 41 and is disposed at the front of the diaphragm 10, the dynamic microphone further including a second permanent magnet 43 disposed on a part of the resonator 40 so as to face the center pole piece 22, the second permanent magnet 43 being polarized in such a way that the same poles of the first permanent magnet 21 and the second permanent magnet 22 face each other.

Abstract: An electro-acoustic drive unit includes at least one permanent magnet assembly and at least an inner pole piece and an outer pole piece forming a pair of pole pieces, the permanent magnet assembly together with the pair of pole pieces forming a magnetic circuit with a pole gap for exciting a voice coil assembly. The pole gap is arranged to provide a magnetic field directed radially with respect to a center axis of the loudspeaker, and the permanent magnet assembly includes at least two permanent magnetic bars, with radially extending magnetization direction with respect to the center axis of the loudspeaker.

Abstract: Improved loudspeakers, systems and components are adapted to interconnect with many forms of communication media. In one embodiment, a speaker is mountable within a receptacle. The speaker includes a magnetic driver and a diaphragm mounted to a frame. The frame includes a mounting member extending from a surface of the frame behind the flange plane. The mounting member is engagable in a notch formed in the receptacle for securing the speaker within the receptacle. In another embodiment, a low-profile loudspeaker has a front-mounted magnetic driver disposed within a cone-shaped acoustic diaphragm. The magnetic driver includes a first rare earth magnet centrally disposed within an electromagnetic shielding material. In another embodiment, a low-profile, two-way loudspeaker includes a cone-shaped diaphragm and a dome-shaped (tweeter) diaphragm. A front-mounted magnetic driver comprises first and second rare earth magnets each centrally disposed within electromagnetic shielding material.

Abstract: An electro-acoustic transducer according to the present invention comprises: a diaphragm; a casing which is formed with an opening in a part thereof for directly or indirectly supporting therein the diaphragm; a first magnetic pole section which is provided on a side of the opening with respect to the diaphragm and has a magnetic pole at a surface thereof which faces the diaphragm; a second magnetic pole section which is provided on a side of an inner bottom surface of the casing with respect to the diaphragm and has a magnetic pole at least a part of a surface thereof which faces the first magnetic pole section through the diaphragm; and a drive coil which is provided on the diaphragm so as to be located in a magnetic gap formed by the first and second magnetic pole sections for generating a driving force so as to cause the diaphragm to vibrate in a direction perpendicular to a surface of the diaphragm.

Abstract: A loudspeaker including a frame, a movable diaphragm that oscillates, and a suspension for mounting the diaphragm to the frame, where the suspension comprises a flexible surround having a substantially enclosed space where at least a portion of the flexible surround is air permeable.

Abstract: One embodiment of a low-profile transducer includes a at least one fin perpendicularly mounted on a planar diaphragm, with a voice coil mounted onto the fin. The voice coil may reside in a strong uniform magnetic field. The locations at which the diaphragm is connected to a frame may be coplanar with a center of mass of the diaphragm. The three-dimensional structure of diaphragm and fins may be formed using origami techniques.

Abstract: A sound recording and/or sound reproducing part loosely anchored/connected to a second part wherein the sound recording and/or sound reproducing part is levitated on a magnetic field. The sound recording and/or sound reproducing part and the second part in combination forms a first sound recording and/or sound reproducing device. The sound recording and/or sound reproducing part can be used within on or more of the following devices; a loud speaking telephone, a telephone, wireless communication equipment, a mobile phone, a Bluetooth device, a videoconference terminal, a hearing aid or active ear protection equipment.

Abstract: One embodiment of a low-profile transducer includes a at least one fin perpendicularly mounted on a planar diaphragm, with a voice coil mounted onto the fin. The voice coil may reside in a strong uniform magnetic field. The locations at which the diaphragm is connected to a frame may be coplanar with a center of mass of the diaphragm. The three-dimensional structure of diaphragm and fins may be formed using origami techniques.

Abstract: A loudspeaker is provided that satisfies requirements for both a small size and a high sound pressure. In addition, the heat capacity of the magnetic circuit and the heat dissipation of the voice coil are improved in this loudspeaker. Using at least two pieces of bar magnets (21), an outer magnet type magnetic circuit is structured in which the magnetic gap comprising an upper plate (22) and a lower plate (23) has a straight section. Also, the configuration of the voice coil (28) is that of a track.

Abstract: An electro-acoustic drive unit including at least a first and a second drive unit, each provided with a pole gap for exciting respective voice coil assemblies, at least one permanent magnet means is arranged to be a part of the magnetic circuit of both the first and the second drive unit. The pole gaps are arranged to provide magnetic fields directed radially with respect to a center axis of the loudspeaker, and the permanent magnet means has radially extending magnetization direction with respect to the center axis of the loudspeaker.

Abstract: An electroacoustic transducer comprising a magnetic circuit of a magnetically conductive material with a pair of opposed surfaces defining a gap therebetween, the magnetic circuit comprising a magnet inducing a magnetic field in the gap, the magnet having a surface constituting one of the opposed surfaces. The magnetic circuit further comprises a diaphragm and a coil having electrically conducting paths secured to the diaphragm. The coil has portions of its paths situated in the gap.

Abstract: A transducer utilizes a sound-producing member positioned in the area of magnetic flux concentration between magnetic poles of opposite polarity. The sound-producing member is variably vibratable in a magnetic structure between the poles to generate acoustic waves, and an acoustic conduit carries the acoustic waves through the magnetic poles e to a location outside the magnetic structure.

Abstract: A magnetic circuit for a speaker device includes: a yoke which has magnetism and has a center pole formed into a column shape; and plural flat plate-shaped magnets which are uniformly arranged around the center pole and form a magnetic gap with the center pole. Each of the magnets is magnetized in a direction in parallel with a thickness direction and in a direction of the center pole. The magnetic circuit for the speaker device is a radial-type magnetic circuit. Since each of the flat plate-shaped magnets is formed not into a circular arc shape but into a flat plate shape, it becomes easy to form the magnets, and the number of procedures of forming of the magnets can be reduced. Additionally, since each of the flat plate-shaped magnets is magnetized in the thickness direction, a special magnetization machine becomes unnecessary. Thus, the number of procedures of magnetizing of the flat plate-shaped magnets can be reduced. As a result, the manufacturing cost of the magnetic circuit can be reduced.

Abstract: A speaker and a magnetic circuit for a speaker, in which the high quality sound is obtained, are provided using a structure which is thin, light-weight and symmetrical in the vibration direction. In three sheets of layered magnets, the first magnet of the first layer and the third magnet of the third layer are arranged in the magnetic directions which repel each other, and the polarity of second magnet of the second layer is arranged perpendicularly to the polarity of the first and third magnets of the first and third layers at the top and bottom thereof. A voice coil wound near the center of a voice coil bobbin is arranged to oppose the second magnet of the second layer of the magnetic circuit composed of the three layers, and the same vibration systems composed of the diaphragms and edges are connected to both the ends of this voice coil bobbin.

Abstract: A multiple magnet dual-gap loudspeaker may generate increased magnetic flux to drive voice coils generating sound from the loudspeaker. The dual-gap dual-voice-coil loudspeaker allows enhanced loudspeaker performance. The dual-gap loudspeaker includes a frame supporting the loudspeaker, at least two voice coils resiliently mounted to the loudspeaker frame by a former, a center support positioned within the voice coils, and at least two magnets. The magnetic flux from each of the magnets is directed within the gaps formed between the center support and the voice coils.

Abstract: The invention relates to an electromagnetic driver comprising a soft magnetic core in the form of an E with three legs and a back, an alternating field driver, magnetically coupled to the soft magnetic core, for generating an alternating magnetic field in the soft magnetic core, depending upon a sound signal, a constant field driver magnetically coupled to the soft magnetic core for generation of a constant magnetic field in the soft magnetic core, a soft magnetic element for coupling to the plate of the planar diaphragm loudspeaker, lying opposite the back and magnetically closing the legs across at least one small induction gap, whereby the constant field and the alternating field are asymmetrically superimposed such that a resulting force, or a resulting torque on the soft magnetic element, is proportional to the sound signal.

Abstract: An electromagnetic transducer includes an electromagnetic dual-coil or multi-coil driver having at least one spacer member placed between at least two permanent magnets. The inclusion of at least one spacer member increases the axial dimension of the magnetic assembly of the driver so that the magnetic gaps in a dual-coil or multi-coil driver are moved farther apart than would occur with a corresponding electromagnetic driver using a permanent magnet instead of two permanent magnets separated by a spacer member.

Abstract: An electromagnetic transducer is described including a magnet assembly (50) and a conductive drive coil (52). The magnet assembly provides an emanating magnetic field within which the drive coil is located. The drive coil is a flat ring coil having a width that is equal to or greater than its height. As assembled, the drive coil is mounted in close proximity to the magnet assembly such that relative axial motion may occur between them during use. In one embodiment, the magnet assembly includes two permanent disc magnets (64), (66) having axial magnetizations and being oriented with like poles facing one another to produce a radially emanating magnetic field. In another embodiment, the magnet assembly includes a pair of axially magnetized permanent ring magnets (64), (66) also oriented with like poles facing one another.

Abstract: A single end planar magnetic speaker system having at least one thin film, flexible diaphragm (72, 90) having a front side and a rear side for converting an input electrical signal into a corresponding acoustic output, the at least one diaphragm including a predetermined conductive region (76) and a predetermined non-conductive region; a magnetic structure (92) utilizing nonferite high energy magnets of a predetermined thickness wherein the magnets are each at least as wide as they are deep; the magnets having a magnetic strength wherein when compared to magnets of a ferrite type of same width as the nonferite high energy magnets but which have increased depth to yield at least nearly the same magnetic strength as the high energy magnets in the magnetic structure, doubling the depth of the high energy magnets in the magnetic structure, doubling the depth of the high energy magnets in the magnetic structure yields an increase in speaker sensitivity of at least 3 dB while the doubling the depth of the ferrite t

Abstract: An electromagnetic driving unit includes a magnet part and a coil part that is translatable along a translation axis with respect to the magnet part. A diaphragm extends from the coil part in a substantially radial direction with respect to the translation axis of the coil part. The magnet part includes two permanent magnets and an intermediate magnetic pole element that is sandwiched between the permanent magnets when viewed along the translation axis of the coil part. In order to improve the efficiency of the driving unit, the permanent magnets and the intermediate magnetic pole element are sandwiched between two external magnetic pole elements, and all pole elements have pole faces that are magnetically directed towards the coil part.

Abstract: An electromagnetic transducer such as an audio speaker, having a motor structure in which a shorting ring that sinks eddy currents also serves as a permanent fixture to provide coaxial alignment of two or more components within the transducer. These components could include various combinations of the yoke, the top plate, the magnet, and/or other parts. Ideally, the shorting ring extends axially as close as possible to the voice coil, to a position immediately adjacent the magnetic air gap.

Abstract: An electro-dynamic loudspeaker includes a frame, a plurality of magnets and a diaphragm. The frame includes a molded plastic body. The magnets may be molded into the frame in a determined configuration. The frame is mechanically coupled to the diaphragm such that the magnets are a determined distance from the diaphragm. The diaphragm may include a conductor applied to a surface of the diaphragm. The diaphragm may be driven by a motive force created when current passes through the conductor within a magnetic field formed by the magnets. The electrical current may be varied to create an acoustical output from the electro-dynamic loudspeaker.

Abstract: A magnet assembly having inner and outer yokes of magnetic flux conductive material which together define an annular air gap and a radially oriented magnet sandwiched between the inner and outer yokes such that a first face of a first magnetic polarity contacts the inner yoke and a second face of a second opposite magnetic polarity contacts the outer yoke, characterised by an axially oriented magnet forming part of the magnet assembly, and wherein the radially oriented magnet is annular and has opposed axial ends, and the inner and outer yokes are annular and together enclose one axial end of radially oriented magnet to define the air gap, and wherein the axially oriented magnet is disposed adjacent to the other axial end of the radially oriented magnet, whereby the inner and outer yokes and the axially oriented magnet together reduce flux leakage from the magnet assembly.

Abstract: The invention relates to an electromagnetic driver comprising a soft magnetic core in the form of an E with three legs and a back, an alternating field driver, magnetically coupled to the soft magnetic core, for generating an alternating magnetic field in the soft magnetic core, depending upon a sound signal, a constant field driver magnetically coupled to the soft magnetic core for generation of a constant magnetic field in the soft magnetic core, a soft magnetic element for coupling to the plate of the planar diaphragm loudspeaker, lying opposite the back and magnetically closing the legs across at least one small induction gap, whereby the constant field and the alternating field are asymmetrically superimposed such that a resulting force, or a resulting torque on the soft magnetic element, is proportional to the sound signal.

Abstract: A planar electro-acoustic transducer has an adjustable back cap option that provides a dipole/monopole radiation that has different roll-off characteristics. The planar electro-acoustic transducer includes a diaphragm and a plurality of front and rear magnetic bars. Each magnetic bar has a side facing the diaphragm and disposed adjacent thereto. The thickness of each rear magnetic bar is larger than the thickness of each front magnetic bar. The thickness of each front magnetic bar is less than a quarter-wavelength of a cavity resonance at 10 kilohertz. The planar electro-acoustic transducer also includes a non-magnetic acoustically transparent metallic mesh that is disposed coplanarly with the sides of the front and rear magnetic bars that face the diaphragm.

Abstract: An electroacoustic transducer 20, such as a speaker, a headphone, an earphone, a microphone, an acoustic wave sensor, etc., includes magnet plates 21 and 22, the entirety of which are formed like a disk or a ring; and an acoustic diaphragm 23 disposed parallel to said magnet plates 21 and 22 and having a conductor formed on the plane thereof; wherein a component parallel to the vibration plane of said acoustic diaphragm 23 is zero or in the radius direction of said magnet plates 21 and 22 in the direction of magnetizing respective partial areas of said magnet plates 21 and 22, and angles formed by said magnetizing direction with respect to the vibration plane of said acoustic diaphragm 23 are made gradually different from each other in accordance with the distance from the center axis of said magnet plates 21 and 22.

Abstract: A speaker includes a first magnet; a second magnet provided so as to surround the first magnet; a yoke for connecting the first magnet and the second magnet; a first voice coil; a second voice coil; a first diaphragm connected to the first voice coil; a second diaphragm oppositely provided to the first diaphragm with respect to the first magnet and connected to the second voice coil; a first magnetic plate provided between the first diaphragm and the first magnet; and a second magnetic plate provided between the second diaphragm and the first magnet. The first voice coil is provided in a first magnetic gap between the first magnetic plate and the yoke. The second voice coil is provided in a second magnetic gap between the second magnetic plate and the yoke.

Abstract: The present invention relates to a multifunctional device, which is particularly applicable to a twin magnet loop (called TML) transducer with both vibrating and sound functions. The present invention integrates an inner and an outer magnet loop of TML into one device, which can be used as a vibrator and a speaker. A disc-shaped pole core, a flange bowl-shaped magnetic transfer, an annular pole piece, a cylindrical magnet and an annular magnet constitute the inner and outer magnetic loops; wherein the disc-shaped pole core is placed on the cylindrical magnet and centered with the flange bowl-shaped magnetic transfer; the annular magnet and the annular pole piece are overlaid together under the ring of the flange bowl-shaped magnetic transfer; the entire of the TML assembly is connected with a housing base via a resilient plate.

Abstract: To realize a speaker device capable of significantly improving sound quality with a simple construction. The speaker device applies electromagnetic force to a voice coil based on a supplied audio signal, and generates a sound wave according to the audio signal by vibrating a vibratory plate fixed to the voice coil.