Abstract: A driver unit is fixed to a stand. A front box and a rear box are directly fitted to the stand through a buffer material. A box comes into contact with the driver unit through a buffer material and is fixed to the stand. Therefore, sound of the driver unit is not transmitted to the box and the drop of sound quality of the speaker can be prevented. The driver unit is fixed to the stand at an immovable foundation, and sound energy can be efficiently transmitted from a speaker cone to the air.

Abstract: A loudspeaker for vehicles having cabins, the loudspeaker including a diaphragm including a first, planar portion for radiating acoustic energy and a second, planar portion for transmitting vibrational energy from a voice coil driver to the first portion. The first portion is incorporated into an inner surface of the vehicle's cabin. The second portion extends from the first portion to a location outside of the cabin, where the voice coil driver is located.

Abstract: A diaphragm subassembly comprises a voice coil, a diaphragm, a frame, and a pair of terminal members. A magnetic circuit unit comprises a yoke, a magnet, and a base. The diaphragm subassembly and the magnetic circuit unit are accommodated in a bottomed cylindrical cover. In the manufacturing process, the cover is placed with the open end directed upward. The diaphragm subassembly, the yoke, the magnet, and the base are dropped into the cover in this order. The manufacturing process of a dynamic electroacoustic transducer is thereby simplified.

Abstract: An electroacoustic transducer (1) has a membrane (19), which has a membrane axis (5) and a ring-shaped pleats area (22), the pleats area (22) being provided with a multitude of pleats (26, 27, 28, 32, 33, 34, 38, 39, 40), in which diametrically opposed pleats are embodied differently with regard to at least one of the pleat parameters.

Abstract: An electroacoustic transducer of small dimensions has a cup-shaped component made of a metallizable plastic material embedded in a housing component having a housing shape and being of a non-metallizable plastic material. The cup-shaped component has an inner surface provided with a metal coating. A magnet is arranged in the cup-shaped component. A diaphragm is connected to the housing component and has an oscillation coil configured to interact with the magnet.

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 loudspeaker is provided, which includes a frame, a voice coil bobbin, and a diaphragm connected to the frame and the voice coil bobbin, wherein the diaphragm is connected to the voice coil bobbin in such a manner that a cone angle between the diaphragm and the voice coil bobbin becomes small enough to obtain a preferable treble reproduction threshold frequency, the diaphragm ha a first connected portion connected to the voice coil bobbin and a second connected portion connected to the frame, and the diaphragm has an arch-shaped cross section so as to have a top portion formed outward from both the first connected portion and the second connected portion.

Abstract: A diaphragm for electroacoustic transducers including loudspeakers as formed substantially in a dome shape having an outer periphery of a circular shape and made excellent in tone quality is provided. The dome shape of the diaphragm has an irregular section with a central arcuate edge line of a radius of curvature across the circular outer periphery and passing through an apex of the dome shape, and side surfaces formed on both sides of the central edge line respectively to have side edge lines intersecting at right angles the central edge line and having a radius of curvature larger than that of the central edge line. The side edge lines of both side surfaces are of constant radius of curvature at least in one of the surfaces or of mutually equal radius of curvature at all positions intersecting the central edge line, to be mutually asymmetric or symmetric for dispersing resonating portions over the whole area of the dome shape.

Abstract: A speaker includes a disk-shaped base. A substantially hemispherical surface vibrator is fitted into a substantially circular groove formed in the base to be bonded therein. Terminals are attached to electrodes located on both surfaces of the vibrator. The edge portion of the vibrator is bonded with a first adhesive, and further, its circumference is bonded with a second adhesive. The first adhesive has a sufficient bonding strength between the vibrator and the base. The second adhesive has a lower elastic modulus than the first adhesive.

Abstract: A speaker apparatus is provided. A frame has a projecting portion projecting toward a diaphragm at the periphery of the frame. The diaphragm has a rising portion extending opposite to the frame from the periphery of the diaphragm and having an outside surface along an inside surface of the frame projecting portion. The outside surface of the rising portion is adhered to the inside surface of the frame projecting portion.

Abstract: A speaker device is capable of accurately generating sound even within a high audio region, without high sound pressure even when generating a large sound. The speaker device includes a sound-producing vibrator having a vibrating body which is, for instance, a semi-spherical piezoelectric ceramic. Electrodes are provided on both surfaces of the vibrating body. An input signal from an amplifier is input between the electrodes so that the vibrating body is vibrated and sound is produced. The resonant frequency of the sound-producing vibrator is set higher than about 20 kHz, which is the upper limit of the human audible range. Furthermore, the thickness of the vibrating body is increased and its mass is increased.

Abstract: An electroacoustic transducer (1) has a membrane (19), which has a membrane axis (5) and a ring-shaped pleats area (22), with the pleats area (22) being provided with a multitude of pleats (26, 27, 28, 32, 33, 34, 38, 39, 40), with diametrically opposed pleats being embodied differently with regard to at least one of the pleat parameters.

Abstract: A speaker device includes a speaker diaphragm composed of a selected acoustic diaphragm material whose acoustic loss coefficient (tan &dgr;) is more than 0.02 in a frequency band over 20 kHz, and including a dome positioned at the center of the diaphragm and shaped to be substantially arcuate in its cross section, with an edge positioned outside the dome and formed integrally therewith through a link; and a conductive one-turn ring inserted into a magnetic gap and bonded fixedly, at one end thereof, to the link between the dome and the edge of the speaker diaphragm. In this device, signals of a frequency band over 20 kHz are reproduced by utilizing the split vibrations of the speaker diaphragm.

Abstract: An improved speaker structure includes dual suspension edges connecting a support seat, a sound ring and a diaphragm. Therefore, when the speaker outputs, the dual suspension edge will not deviate and can perform a highly vertical cutting movement. Besides, the dual suspension edge can perform a flip-flop movement and distribution, and can compensate insufficient tensile force during reverse vibration so as to increase power, reduce distortion, and enable the diaphragm to be independently secured to a top portion of the sound ring to obtain better sound quality.

Abstract: A loudspeaker having a back plate, a driver attached to the back plate, the driver being responsive to an electrical signal, an enhancer having a neck and a mouth, the neck attached to the driver and movable in accordance with the movement of the driver, a thin film membrane, the membrane attached to the enhancer, the membrane stretched over the frame, a frame for supporting the membrane and maintaining it in a taut state, and a rubber type adhesive for dampening the membrane resonances and for adhering the membrane to the frame. Clarity of sound can be further improved by including a plurality of sound breathers in the back plate of the speaker. For improved sound radiation capability, the size and the shape of the enhancer can be modified in various ways, including a frustoconical, parabolic, or bell-shaped enhancer.

Abstract: An electro-acoustic converter, comprising a barrel shaped diaphragm (2) formed about a longitudinal axis (3) and comprising first and second annular opposed ends (4, 5), and a first electrically driven vibration generator (6-11) for inducing a vibrational movement in the first annular end in the direction of the longitudinal axis.

Abstract: A speaker device includes a speaker diaphragm composed of a selected acoustic diaphragm material whose acoustic loss coefficient (tan &dgr;) is more than 0.02 in a frequency band over 20 kHz, and including a dome positioned at the center and shaped to be substantially arcuate in its cross section, and an edge positioned outside the dome and formed integrally therewith through a link; and a conductive one-turn ring inserted into a magnetic gap and bonded fixedly, at one end thereof, to the link between the dome and the edge of the speaker diaphragm. In this device, signals of a frequency band over 20 kHz are reproduced by utilizing the split vibrations of the speaker diaphragm.

Abstract: A reflection speaker assembly includes a cylindrical body having an aperture, a reflector, a tweeter type speaker for higher frequencies and a midrange type of speaker for middle frequencies. The tweeter is located on the wall of the cylindrical body. The midrange is mounted inside the body. The aperture is located between a base containing the reflector and a housing containing the midrange speaker. In one embodiment, the reflector is positioned opposite the midrange speaker in the body and comprises in a flat surface set at an angle relative to the midrange speaker. In a second embodiment, the reflector is positioned opposite the midrange speaker in the body and is roughly conical. Sound waves radiated from the midrange speaker are reflected by the reflector, and are dissipated to the outside through the aperture.

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: The compression driver includes an annular diaphragm with a voice coil which is disposed in a magnetic gap of a magnet assembly which supplies a magnetic field to the voice coil. The annular diaphragm has a first support portion, a second support portion, a first curved resilient portion, a second curved resilient portion and a voice coil support portion which is disposed between the first and second resilient curved portions. The voice coil is wound on the voice coil support portion. The voice coil is disposed in the magnetic gap of the magnet assembly. The compression driver also includes an inner support ring and an outer support ring. The inner support ring has a bottom surface with a first curved groove. The outer support ring has a bottom surface with a second curved groove and is disposed concentrically around the inner support ring.

Abstract: A sound reproduction device or a microphone comprising an enclosure (2) which is made of a substantially gas permeable flexible material and an electrical transducer (1) having at least one connection (4, 5) with the enclosure, and usually two connections, to impart movement to the enclosure where the device acts as a loudspeaker or to receive movement of the enclosure to generate an electrical signal where the device acts as a microphone. The enclosure is adapted to be stressed by internal pressure and forms a concavity centered on at least one of the connections with the electrical transducer, which concavity acts as an acoustic diaphragm.

Abstract: A speaker comprising a magnetic circuit containing at least a magnetic gap, a frame connected to the magnetic circuit, and an integral unit consisting of a ring shaped voice coil bobbin unit which is wound around with coil to be coupled in the magnetic gap, and a diaphragm unit formed in the shape of an inverse letter “U” disposed on an upper edge of the voice coil bobbin unit. This speaker provides enhanced rigidity, a reduction in production/assembly cost, and an improved sound pressure level.

Abstract: The present invention relates to an electric acoustic converter used as a speaker or a receiver of a mobile communication device such as a portable telephone or the like. In the electric acoustic converter according to the present invention, the size reduction and thinning of the thickness of the electric acoustic converter can be promoted by providing surface-like rear surface terminals 81 and 82 on the exposed surface 33 which is a rear surface of the yoke 3.

Abstract: A special Hi-Fi tweeter having a ring-shaped dome portion with a retracted central portion fixed to the tweeter chassis was found to present an objectionable drop of response in the 18-20 KHz range. According to the invention this problem is eliminated or minimized in placing in front of said central area a forwardly projecting, generally conical wave guide (18) that will minimize interferences between sound waves radiated forwardly and inwardly from the ring shaped dome. An alternative solution is to arrange, in front of a wider central portion, a shield member directly preventing external radiation from the critical central area, still without changing the shape of the diaphragm. However, also certain modifications are proposed, which may well be used in connection with ordinary dome speakers.

Abstract: The compression driver includes an annular diaphragm with a voice coil which is disposed in a magnetic gap of a magnet assembly which supplies a magnetic field to the voice coil. The annular diaphragm has a first support portion, a second support portion, a first curved resilient portion, a second curved resilient portion and a voice coil support portion which is disposed between the first and second resilient curved portions. The voice coil is wound on the voice coil support portion. The voice coil is disposed in the magnetic gap of the magnet assembly. The compression driver also includes an inner support ring and an outer support ring. The inner support ring has a bottom surface with a first curved groove. The outer support ring has a bottom surface with a second curved groove and is disposed concentrically around the inner support ring.

Abstract: Disclosed is a speaker having a device capable of generating sound and vibration for notifying reception of an incoming call when a radio incoming signal is received. The speaker comprises a cylindrical frame; magnetic field forming means disposed in the cylindrical frame for forming first and second magnetic flux; a sound generating section for producing electromagnetic force by interaction with the first magnetic flux and thereby generating sound, when a signal having a frequency which is no less than a predetermined frequency, is applied thereto; and vibration generating means for producing electromagnetic force by interaction with the second magnetic flux and thereby generating vibration, when a signal having a frequency which is less than the predetermined frequency, is applied thereto.

Abstract: A speaker and its production method in which productivity can be enhanced and characteristics can be easily improved. A frame 14 of a speaker 10 is divided into a first frame body 15 and a second frame body 44 and the first and second frame bodies 15, 44 can be put together by engaging. A voice coil 35, a magnetic circuit 16 and a damper 17 are attached to the first frame body 15 constituting a first assembly 11. A cone paper 45 is attached to the second frame body 44 constituting a second assembly 12. Claw-shaped hooks formed on the second frame body 44 are to catch an engaging part 21 formed at the first frame body 15 in order to connect the first assembly 11 and the second assembly 12 to construct the speaker 10. The two assemblies 11, 12 can be produced in parallel. This leads to an improvement in the production efficiency.

Abstract: A speaker has a substantially reduced size, is efficient in the low sound range and is unidirectional relative to the plane of installation or support of the speaker. The speaker includes a vibrator having a semispherical vibrating body made of a piezoelectric material polarized in a thickness direction. Electrodes are provided on the inner and outer surfaces of the vibrating body. A cavity is created inside of the vibrator. A sound path in the form of a horn includes inner parts of a first cylinder which communicates with the cavity, a second cylinder, a third cylinder, a fourth cylinder, a fifth cylinder and other cylinders. Cutouts functioning as openings of the sound path are disposed almost along the whole azimuth of the fifth cylinder at the outside of the horn relative to the plane of speaker support.

Abstract: An electro-acoustic transducer comprises a metal single-piece blade diaphragm having a very good heat conductivity and mechanical characteristics, the metal blade of which is resiliently suspended and supports the acoustical current wire fixed at the center of mass thereof to the active metal surface of the transducer, so that the acoustical current wire communicates to the blade the heat which is produced because of the acoustical current and added to that generated in the blade because of the deformation of the resilient suspension.

Abstract: An electrodynamic acoustic transducer with a coil which projects into an air gap subject to an electromagnetic field, wherein an acoustic short circuit is prevented. The electrodynamic transducer has a membrane comprising two differently profiled portions, an acoustically effective central portion with a convexity in form of a spherical cap, and a ring-shaped bead which borders the central portion and serves to elastically support the membrane. The ring-shaped bead is arranged beneath the central portion and extends radially inwards starting from a coil seat of the coil. The air gap is sealed by means of a liquid or solid medium, such as ferrofluid, such that an acoustic short circuit between the front volume and the rear volume of the transducer is prevented.

Abstract: A dome speaker comprises a dome section including a vibrating diaphragm having a dome shape, an annular edge damper section provided surrounding the dome section, an annular coil holder provided between the dome section and the annular edge damper section for holding a voice coil. In particular, the dome section further includes a cap having substantially the same shape as the vibrating diaphragm, said cap being bonded on the said vibrating diaphragm.

Abstract: An improved transducer which includes a rigid frame and a permanent ring magnet mounted to the frame. A small bobbin, preferably formed of aluminum foil, is sized and arranged to fit within the open end of the magnetic gap while permitting motion of the bobbin therein. A voice coil is wound on the bobbin and connectable to receive an audio signal, similar to a conventional voice coil driver system. A pair of flexible, curved diaphragms are disposed in the frame, generally free to move except for a distal end of each diaphragm which is fixed to the frame. The diaphragms can be of generally cylindrical or partial-cylindrical shape.

Abstract: A horn speaker system includes a dome-shaped diaphragm, a coil bobbin, a phase equalizer, and a magnetic circuit. The coil bobbin is integral with the dome-shaped diaphragm, and a voice coil is wound on the coil bobbin near a free end thereof. The magnetic circuit coacts with the voice coil for producing forces to actuate the dome-shaped diaphragm. The magnetic circuit includes a cylindrical magnet, a first annular yoke attracted to one end of the cylindrical magnet and having a central opening, a plate cooperating with the first yoke in defining a gap in which the coil bobbin is inserted, and a second yoke attracted to an opposite end of the magnet. The magnet, the first yoke, the first plate, and the second yoke jointly make up a closed magnetic circuit. The phase equalizer serves to keep sounds outputted from the dome-shaped diaphragm in phase. The phase equalizer is mounted on the first yoke and has a plurality of slits defined therein.