Abstract: The surrounding structure of the loudspeaker forms an annular structure, including attaching parts and curved part. The cross section of the curved part is in a hollow and approximately elliptical form. The height along the major axis of the ellipse is made parallel to the center axis of the vibrating diaphragm of the loudspeaker while the width along the major axis of the ellipse is set in the direction orthogonal to the center axis of the vibrating diaphragm. In the elliptical surrounding structure having such a structure, the width in the cross section of the surrounding structure of the loudspeaker can be made narrow in comparison with a semi-circular surround, whereby the linearity of the amplitude and the maximum displacement are increased.

Abstract: A damper 3A is provided with an inner peripheral waveform portion 11 and an outer peripheral waveform portion 12. A flat portion 10 is provided between the inner peripheral waveform portion 11 and the outer peripheral waveform portion 12. When the damper is used for a loudspeaker, the flat portion 10 does not elastically deform in a radial direction R, so that linearity of the damper 3A in a vibrating direction Z is ensured by elastic deformation of the waveform portions. In addition, a rolling phenomenon of a voice coil bobbin and a diaphragm can be suppressed.

Abstract: A damper 3A is provided with an inner peripheral waveform portion 11 and an outer peripheral waveform portion 12. A flat portion 10 is provided between the inner peripheral waveform portion 11 and the outer peripheral waveform portion 12. When the damper is used for a loudspeaker, the flat portion 10 does not elastically deform in a radial direction R, so that linearity of the damper 3A in a vibrating direction Z is ensured by elastic deformation of the waveform portions. In addition, a rolling phenomenon of a voice coil bobbin and a diaphragm can be suppressed.

Abstract: A loudspeaker comprising a bobbin, a coil wound around an outer surface of the bobbin, a magnetic circuit having a magnetic gap the coil is inserted, a first cylinder fixed to the outer surface of the bobbin, a second cylinder connected with the first cylinder, a diaphragm and a damper coupled to the outer circumferential surface of the second cylinder, an edge coupled to the diaphragm, a frame on which an outer circumference of the damper and an outer circumference of the edge are fixed, and terminals fixed on the frame and electrically connected with the coil. In a speaker of the present invention, the outer circumference of a yoke constituting the magnetic circuit has a plurality of slits, while the first cylinder and the second cylinder are connected together by a plurality of radially-disposed joints. Speakers in the present invention have a flat profile yet they are compatible with large amplitude and high output power, capable of reproducing a wide range of sounds from a low tone to a high tone.

Abstract: A speaker includes: a frame; a magnetic circuit fixed to the frame; a diaphragm fixed to the frame so as to be capable of vibrating in a predetermined direction; a driving force transmitting member connected to the diaphragm; and a damper for supporting the driving force transmitting member, wherein the magnetic circuit is positioned between a first plane and a second plane, the first plane being parallel to the diaphragm and defined as a plane with which at least a portion of the magnetic circuit is in contact, and the second plane being parallel to the diaphragm and defined as a plane with which at least a portion of the magnetic circuit is in contact, and one end of the damper is connected at a position between the first and second planes, and the other end of the damper is connected at another position between the first and second planes.

Abstract: A diaphragm is gained by the co-molded of a dome part, a voice coil junction part, a cone part and a peripheral part through the injection mold of thermoplastic resin. The thickness of the central part of the dome is made great so that the resonance amplitude in this part becomes small. In addition, an annular rib is integrally provided to the voice coil junction part so as to increase the junction strength between the diaphragm and the voice coil bobbin. Thus, the electromagnetic driving force of the voice coil can be effectively transmitted to the diaphragm so that a loud speaker with excellent characteristics can be gained.

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 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: A speaker includes a diaphragm, a frame accommodating the diaphragm and an edge attached to an outer periphery of the diaphragm as well as to an inner periphery of the frame so as to retain the diaphragm within an interior of the frame. The edge has a thickness which is smallest at substantially a central portion between the diaphragm and the frame and the vicinity thereof, and increases toward the diaphragm and the frame.

Abstract: A speaker includes a diaphragm, a frame accommodating the diaphragm and an edge attached to an outer periphery of the diaphragm as well as to an inner periphery of the frame so as to retain the diaphragm within an interior of the frame. The edge has a thickness which is smallest at substantially a central portion between the diaphragm and the frame and the vicinity thereof, and increases toward the diaphragm and the frame.

Abstract: The loudspeaker includes: a frame; a magnetic circuit portion; a diaphragm transmitting air vibration; a cylindrical voice coil bobbin connected to the diaphragm; a voice coil fixed to an outer peripheral portion of the voice coil bobbin; and a damper holding the voice coil in such a manner that the voice coil is capable of vibrating in a magnetic gap formed between an annular top plate and a center pole included in the magnetic circuit portion. The damper includes a flat portion which has a hole for passing the voice coil bobbin therethrough at its center, and a plurality of roll structures connected to a periphery of the flat portion and having a cross-section including a bent periphery. Each of the plurality of roll structures is fixed to the frame, and the hole of the flat portion is fixed to an outer peripheral surface of the voice coil bobbin.

Abstract: A speaker has a diaphragm of which plane shape as seen from a vibrating direction has a major axis and a minor axis, a band-shaped edge connected to the outer circumference of the diaphragm for holding so that the diaphragm may be free to vibrate, and a frame for holding the outer circumference of the edge, wherein a viscoelastic member is affixed to part of the edge and/or diaphragm.

Abstract: The loudspeaker of the invention includes: a frame; a diaphragm, a planar shape thereof being non-axisymmetric having a larger diameter and a smaller diameter when the diaphragm is viewed from a vibration direction thereof; a band-shaped edge portion provided around an outer periphery of the diaphragm, an outer periphery of the edge portion being connected to the frame and an inner periphery of the edge portion being connected to the diaphragm; a cylindrical voice coil bobbin in a non-axisymmetric shape having a larger diameter and a smaller diameter which includes a pair of opposed faces parallel to each other in a larger diameter direction, one end portion of the voice coil bobbin being connected to the diaphragm; a voice coil wound around the voice coil bobbin; a plurality of voice coil bobbin reinforcing members in a plate shape which are bridged between the pair of opposed faces parallel to each other of the voice coil bobbin; and a plurality of magnetic circuits having a gap for applying magnetic fluxes

Abstract: A sound absorber arrangement includes a plurality of sound absorbing layers of porous materials such as glass wool, rock fiber or cellular plastic, and high-polymer films, are alternately laminated in a direction perpendicular to a sound incidence plane. The layer thicknesses are increased in order in a direction away from the sound incidence plane. The sound absorber arrangement makes it possible to make a sound absorbing coefficient constant over the low to high frequency sound range.

Abstract: In a speaker system, the rearward area of a diaphragm is separated into two acoustic regions. One of the two acoustic regions is a rear opening type and the other is a base-reflex type. An acoustic mass, such as a port or a passive radiator, is located between the first and second acoustic regions for providing a phase inversion characteristic.

Abstract: A speaker which is thin but which is capable of providing high-fidelity reproduction and ensuring a suitable level of sound pressure even when it is brought close to a wall. A closed chamber is formed behind one part of a disphragm mounted in an enclosure, and an open chamber is formed behind another part of the diaphragm. At least one voice coil driver unit is connected to the diaphragm. The phase difference between sounds radiated from the front and rear surfaces of the diaphragm is increased as large as possible by using an acoustic duct for the sound radiated through the open chamber, thereby minimizing cancellation of sounds and improving the sound pressure level.

Abstract: A speaker system has an acoustic diaphragm and an image projection screen provided on a surface of the diaphragm integrally therewith so as to enable the user to enjoy both realistic image on the screen and powerful sound reproduced through the diaphragm. The rear surface of the diaphragm is closed at a peripheral portion thereof while the central portion of the rear surface of the diaphragm is opened to the exterior, so that the speaker system can provide a high level of reproduced sound pressure in low-pitched region, while the thickness of the speaker is reduced remarkably. The diaphgram can be driven by a plurality of driving units so that the speaker system can operate only with an ordinary stereophonic amplifier.

Abstract: A speaker which is thin but which is capable of providing high-fidelity reproduction and ensuring a suitable level of sound pressure even when it is brought close to a wall. A closed chamber is formed behind one part of a diaphragm mounted in an enclosure, and an open chamber is formed behind another part of the diaphragm. At least one voice coil drive unit is connected to the diaphragm. The phase difference between sounds radiated from the front and rear surfaces of the diaphragm is increased as large as possible by using an acoustic duct for the sound radiated through the open chamber, thereby minimizing cancellation of sounds and improving the sound pressure level.

Abstract: A diaphragm for loudspeakers comprises chitin as a natural high polymeric material having a large value of Young's modulus and kraft pulp having large mechanical internal loss. Therefore, the deformation and the partial vibrations of the diaphragm during diaphragm operation do not come out due to the use of the chitin, because the flexural rigidity of the diaphragm is considerably large. Mechanical internal loss is also large owing to the use of the kraft pulp. As a result, it is possible to obtain a loudspeaker which has little fluctuation in frequency response, and which provides a superior sound pressure-frequency response, a superior distortion factor and a superior phase response.

Abstract: A digital signal represents a desired amplitude frequency characteristic. A desired transmission characteristic is derived from the desired amplitude frequency characteristic. A sound signal is processed in accordance with the desired transmission characteristic. The processed sound signal is converted by a speaker into corresponding sound. The process of the sound signal corrects and compensates for the original sound pressure frequency characteristic of the speaker and thereby actualizes the desired amplitude frequency characteristic.