Abstract: In a loudspeaker device of the present invention, an interior space of a cabinet 20 is parted into first and second chambers Wb1 and Wb2, a diaphragm 23 on which ring-shaped magnetic boards 29a and 29b are fixed is attached to a parting board 22 via an edge portion 24, and ring-shaped fixed magnets 25 and 27 are provided so as to face magnetic boards 29a and 29b, respectively. Vibration of the diaphragm 23 vibrated by sound pressure from a speaker unit 21 is intensified by forces of attraction of the magnets 25 and 27 in order to reduce an acoustic stiffness of the cabinet 20 and equivalently increase a cabinet volume, thereby realizing satisfactory bass reproduction with a small cabinet.

Abstract: A sound reproducing apparatus includes a display unit, a board 22, a diaphragm panel 23, and an electroacoustic transducer 26. The display unit displays an image on a display surface. The board 22 is composed of a material which transmits visible light and arranged such that a first space is provided between the display surface of the display unit and the board 22. The diaphragm panel 23 is composed of a material which transmits visible light and arranged on the opposite side of the board 22 from the display unit such that a second space is provided between the board 22 and the diaphragm panel 23. The electroacoustic transducer 26 emits sound into the second space.

Abstract: In an electroacoustic transducer of the present invention, a casing supports a diaphragm, a drive coil is provided on the diaphragm, a first magnetic structure has a first space in a center thereof provided within the casing such that a center axis penetrates the first space, and a second magnetic structure has a second space in a center thereof provided within the casing on a side opposed to the first magnetic structure with respect to the diaphragm, such that the center axis penetrates the second space. The first magnetic structure is oriented such that a magnetization direction thereof is parallel to the center axis. The second magnetic structure is oriented such that a magnetization direction thereof is opposite to the magnetization direction of the first magnetic structure.

Abstract: The present invention provides an electronic apparatus including a touch pad. The electronic apparatus also includes a housing and a mechanical acoustic transducer. The housing supports an outer circumferential portion of the touch pad via a suspension to provide a space for sound emission between the housing and the touch pad. The electromechanical acoustic transducer is connected to the housing, and emits sound into the space. When the electromechanical acoustic transducer emits the sound into the space, an energy of the sound emitted causes the touch pad to vibrate and thereby to output sound outside the electronic apparatus.

Abstract: A loudspeaker includes: a frame; a vibrating section including a diaphragm having an internal periphery and an external periphery, a voice coil attached to the internal periphery of the diaphragm, a spider which connects the voice coil to the frame, and a dust cap attached to the internal periphery of the diaphragm; and a surround which connects the external periphery of the diaphragm to the frame, wherein the ratio between the weight of the vibrating section and the weight of the surround is 0.9:1 to 1.5:1.

Abstract: A loudspeaker diaphragm 104 affixed with a coil 103 includes an edge portion located outside of a portion affixed with the coil 103 and a center portion located inside of the portion affixed with the coil 103. The center portion is provided thereon with ribs 202. With these ribs 202, the height of the center portion can be limited to the height of the ribs 202. Therefore, it is possible to save a space of a loudspeaker where the loudspeaker diaphragm is placed, thereby slimming down the loudspeaker. Furthermore, with these ribs, the rigidity of the center portion can be improved without using a conventional solution of forming, for example, a dome shape on the center portion.

Abstract: An electromagnetic transducer, includes: a first diaphragm disposed in a vibratile manner; a second diaphragm provided in a central portion of the first diaphragm, the second diaphragm being formed of a magnetic material; a yoke disposed in a position opposing the first diaphragm; a center pole provided on a face of the yoke that opposes the first diaphragm; a coil substantially surrounding the center pole; a magnet substantially surrounding the coil; and a thin magnetic plate provided between the magnet and the first diaphragm, an inner periphery of the thin magnetic plate being in overlapping relation to an outer periphery of the second diaphragm.

Abstract: An electromagnetic transducer according to the present invention includes: a first diaphragm disposed so as to be capable of vibration; a second diaphragm disposed in a central portion of the first diaphragm, the second diaphragm being made of a magnetic material; a yoke disposed so as to oppose the first diaphragm; a center pole disposed between the yoke and the first diaphragm; a coil disposed so as to surround the center pole; a first magnet disposed so as to surround the coil; and a second magnet disposed on an opposite side of the first diaphragm from the center pole.

Abstract: A sound-driving loudspeaker system achievable with a simple structure and capable of easily improving acoustic characteristics is provided. The loudspeaker system according to the present invention emits sound by driving a diaphragm panel 14 by an electromechanical acoustic transducer 12. The loudspeaker system includes a board 10, the diaphragm panel 14 whose rim is fixedly attached to the board 19 so as to form a space 16 and which has a stiffness lower than that of the board 10, and the electromechanical acoustic transducer 12 for emitting sound into the space 16. With this structure, the diaphragm panel 14 is flexed to be vibrated by the sound emitted from the electromechanical acoustic transducer 12.

Abstract: The present invention relates to an electromagnetic electro-acoustic transducer to be used for generating an incoming indicator tone for mobile phones and the like. A resin magnet 11 is formed with a hard magnetic material and a soft magnetic material, the lowest resonant frequency can be easily set by changing the magnetic flux density in a magnetic gap by changing the compound ratio of the soft magnetic material, a high magnetic flux density is attained by increasing the magnetic permeability of the resin magnet 11 with the soft magnetic material, thus achieving a smaller size as well as a higher sound pressure through an increase in the driving force exerted to the diaphragm.

Abstract: An electromagnetic transducer includes: a first diaphragm disposed in a vibratile manner; a second diaphragm provided in a central portion of the first diaphragm, the second diaphragm being formed of a magnetic material; a yoke disposed in a position opposing the first diaphragm; a center pole provided on a face of the yoke that opposes the first diaphragm; a coil substantially surrounding the center pole; a magnet substantially surrounding the coil; and a thin magnetic plate provided between the magnet and the first diaphragm, an inner periphery of the thin magnetic plate being in overlapping relation to an outer periphery of the second diaphragm.

Abstract: A first magnet is provided in an upper case and a second magnet is provided in a lower case so that these magnets face each other. These magnets are magnetized in opposite directions. A diaphragm having a drive coil is placed between these magnets. Thus, magnetic flux emitted from the respective magnets bends in a direction approximately perpendicular to the initial direction of emission of the flux. In the magnetic field, the component of the magnetic flux in the direction of radiation proportional to the driving force is dominant, and is symmetrical relative to the direction of vibration. Therefore, the sound pressure of the reproduced sound is increased and the secondary harmonic distortion caused by asymmetry of the driving force can be reduced.

Abstract: An electric-mechanical-acoustic-transducer includes a diaphragm; a movable section; a driving section for generating a driving force for vibrating the diaphragm and the movable section; and a suppression section for suppressing a sharpness (Q factor) of a vibration force obtained by the vibration of the movable section.

Abstract: A speaker system includes a display panel for displaying an image; a transparent panel provided such that the image displayed in the display panel is viewed through the transparent panel; an electric-mechanical-acoustic-transducer having a diaphragm for outputting a sound by vibrating the diaphragm in accordance with an electric signal; and an acoustic signal transfer member for transferring the sound output from the electric-mechanical-acoustic-transducer to a space provided between the display panel and the transparent panel. The transparent panel is allowed to be vibrated by the sound transferred to the space from the electric-mechanical-acoustic-transducer via the acoustic signal transfer member.

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: An electromagnetic transducer includes: a first diaphragm; a second diaphragm provided in a central portion of the first diaphragm, the second diaphragm comprising a magnetic material having a first opening in a central portion thereof; a yoke disposed so as to oppose the first diaphragm; a center pole disposed between the yoke and the first diaphragm, wherein the center pole has a shape which allows insertion into the first opening; a coil disposed so as to surround the center pole; and a first magnet disposed so as to surround the coil.

Abstract: A loudspeaker includes: a frame; a vibrating section including a diaphragm having an internal periphery and an external periphery, a voice coil attached to the internal periphery of the diaphragm, a spider which connects the voice coil to the frame, and a dust cap attached to the internal periphery of the diaphragm; and a surround which connects the external periphery of the diaphragm to the frame, wherein the ratio between the weight of the vibrating section and the weight of the surround is 0.9:1 to 1.5:1.

Abstract: An electromagnetic transducer includes a magnetic member, a suspension for supporting the magnetic member at a central portion of the suspension, a diaphragm connected to the suspension, a magnet for generating magnetic flux on the magnetic member, and a coil for generating alternating magnetic flux on the magnetic member.

Abstract: A loudspeaker includes: a bottom plate; a center pole provided upwardly from the bottom plate; a yoke surrounding the center pole and having a plurality of slits; a magnet for providing a magnetic flux for the center pole and the yoke; a coil provided between the center pole and the yoke; a first annular member for supporting the coil; a plurality of support members for supporting the first annular member, the plurality of support members being inserted into the plurality of slits; and a diaphragm supported by the plurality of support members, wherein upper faces of the plurality of support members gradually decrease in height in a direction away from the first annular member, and wherein a lower face of the coil is located below a position at which the diaphragm is supported by the plurality of support members.

Abstract: An electro-mechanical-acoustic transducing device includes: an electro-mechanical-acoustic transducer which has at least one resonance frequency, for converting an input electric signal into only vibration, or into both vibration and sound; a signal supplying unit for supplying a signal in a frequency band which includes at least one of the resonance frequencies of the electro-mechanical-acoustic transducer as the input signal of the electro-mechanical-acoustic transducer; and a frequency detector for detecting a signal component having a frequency corresponding to the mechanical resonance frequency of the electro-mechanical-acoustic transducer in an electric signal which is output from the electro-mechanical-acoustic transducer, and outputting the signal component as a part of an input signal to the signal supplying unit.