Abstract: An open-type magnetic circuitry of loudspeaker includes a lower yoke having a central portion upward projected to form a bobbin, a magnet positioned on top of the bobbin, a voice coil wound around the bobbin and the magnet, and a diaphragm connected at a root portion to the voice coil. The magnetic circuitry of loudspeaker is characterized in that the lower yoke is provided at an upper side surrounding the bobbin with a plurality of radially equally spaced supporting posts, a top end of which being higher than at least a bottom side of the magnet, and that a ring-shaped upper yoke having a central hole is covered onto the top end of the supporting posts, such that heat produced by the voice coil during working could quickly dissipate via the spaces among the supporting posts. Since no heat would accumulate in the loudspeaker, the loudspeaker could always maintain good sound quality.

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: In a speaker which is constructed in a manner that a voice coil bobbin is attached to an inner circumferential portion of a cone type diaphragm while a voice coil is wound around the voice coil bobbin, and the voice coil is inserted into a magnetic gap, the voice coil bobbin is formed of a conductive material while the voice coil being fixed is the voice coil bobbin by a soft bonding agent, and in a very high range, the voice coil is operated as a driving coil while the voice coil bobbin is operated as a short coil.

Abstract: A high stability loudspeaker has a yoke with a plurality of vents installed therein. The yoke is combined to a bottom of a frame of the loudspeaker. A magnet is placed in the yoke. A washer is arranged above the magnet. A periphery of the magnet is surrounded by a voice coil. A coil winding surrounds the voice coil. A combining portion is formed at a periphery of the yoke. The combining portion serves to be combined with a surround connected to a bottom of end of the voice coil. The voice coils is vertically installed in a gap between the portions of the yoke. The top of the voice coil is connected to another surround. Thereby, vibration of the voice coil is confined at the two ends. As a result, the gap between portions of the yoke structure into which the voice coil extends between portions of the yoke is reduced and therefore, the sensitivity of the loudspeaker is increased and the distortion is decreased.

Abstract: Disclosed is a convenient way of mounting the microphone array and associated electronics of a hearing aid on the person, and providing a convenient wireless means for delivering the microphone signals to the ear, and providing a signal processing technique that yields sharp directivity at audio frequencies. The wearer positions her/his body to receive the desired signal and to attenuate surrounding background noise and multipath interference.

Abstract: A multifunction acoustic device has a rotor rotatably supported in a frame, a stator provided in the frame. A permanent magnet is provided on the rotor, a coil is provided for forming magnetic fluxes between the rotor and the stator. Voltage detecting means is provided for detecting a voltage generating at the coil. A voltage detected by the voltage detecting means in the operation of the acoustic device is compared with a reference voltage which corresponds to a voltage generating at abnormal rotation of the rotor and for producing an abnormal signal when the detected voltage is equal or higher than the reference voltage. In response to the abnormal signal, the rotor is rotated from a low speed.

Abstract: According to the invention, this magnetic circuit, of known type with a central magnet, is such that the diameter of said central magnet 8.1 is greater than that of the core 9.1, such that said magnet 8.1 has a peripheral projection 14, which is annular and radial, with respect to the core 9.1. The performance of said magnet is thus improved.

Abstract: An informing apparatus for a mobile communication apparatus is provided, which can be used in a silent mode without a limitation in resonance frequency.

Abstract: A loudspeaker assembly includes a chassis, a magnet assembly supported by the chassis and disposed at a rear side thereof, a moveable voice coil, a rear suspension, and a diaphragm connected to the voice coil and to the chassis. The assembly defines a voice coil gap receiving the voice coil. To improve the cooling of the assembly, particularly when the magnet assembly includes neodymium, the assembly is positioned at least substantially in front of the diaphragm, and the chassis is positioned outwardly of the magnet assembly. Heat generated by the coil, which could adversely affect the magnet, is dissipated by conduction to the chassis and by convection and radiation to ambient air. The rear suspension supports the voice coil, is secured to the assembly and is connected to the chassis only through the magnet assembly and through the diaphragm.

Abstract: An acoustic driver has a voice coil in which adjacent turns of the coil are spaced apart. The driver is placed at one end of a foam-lined, elongated structure, such as a tube. An opposing end of the structure is, in one embodiment, enclosed by a wall that is connected to the structure by a suspension so that it moves in sympathy with the driver. In another embodiment, the structure cooperates with the acoustic driver to form one or more restrictive passageways confined around the driver's motor and an inner surface of the structure. The passageway(s) couple a volume of air in the structure to the exterior of the structure in a manner that reduces the transmission of acoustic energy without creating alternating pressure within the structure that interferes with the movement of the voice coil's diaphragm, at its maximum points of excursion.

Abstract: A pole piece 31 is placed on a lower case 21. A pole piece 31 has a core 32 and a base 33. The bobbin portion 24 extends from the lower case 21 toward the internal space of a case 1 so as to surround the outer periphery of the core 32. The bobbin portion 24 is divided into a plurality of portions along the circumferential direction of the core 32. The bobbin portion 24 has basal parts 26 and elongated parts 27. The pole piece 31 is pressed from the above of the lower case 21 in a state where the bobbin portion 24 is passed through holes 35 of the base 33, to be positioned on the outer periphery of the core 32, so that the pole piece is fitted and placed into the lower case 21. A coil 41 is configured by winding a conductor wire 42 around the elongated parts 27 of the bobbin portion 24.

Abstract: A micro speaker is disclosed. An oscillating plate is secured to the bottom of a protecting cover, and a terminal is installed on a side of the protecting cover, the terminal being electrically connected to a voice coil. A magnetic circuit is secured into a recess of a frame, and the protecting cover is attached on the top of the frame. Accordingly, when disassembling the speaker unit, any damage of the oscillating plate can be excluded. Further, when grounding the terminal to a circuit board, the connecting portion of the terminal is prevented from forming a short circuit.

Abstract: The present invention relates to an miniature actuator especially suitable for hearing aid applications. The actuator according to the present invention operates according to the change in reluctance principle. In particular, the actuator according to the present invention operates in a balanced configuration comprising two planar coils, two magnets, a membrane and a spacer chip providing the necessary back chamber volume.

Abstract: A speaker apparatus includes a frame having a magnetic circuit, a voice coil bobbin installed in the frame to be magnetically coupled to the magnetic circuit, and a diaphragm movably installed in the frame and fixed to the voice coil bobbin so as to be driven by activating the magnetic circuit. The diaphragm has a positioning portion that had been used for securing the diaphragm relative to the magnetic circuit during an installation of the diaphragm in the frame.

Abstract: A case comprises an upper case and a lower case. A vibrating plate is secured to the upper case, a voice coil is secured to an underside of the vibrating plate. Each end portion of the voice coil is engaged in a groove formed in the upper case.

Abstract: A loudspeaker comprising: a magnetic circuit; a plastic frame to be coupled with the magnetic circuit; a voice coil disposed in a magnetic gap of the magnetic circuit; and a diaphragm connected with the voice coil. The frame and the magnetic circuit are coupled together by an elastic fastener provided on the frame. In one exemplary embodiment of the present invention, frame and yoke are coupled together by fitting a plurality of elastic fasteners provided on a circle on the bottom surface of the frame with a yoke of the magnetic circuit. In another exemplary embodiment, the elastic fastener is a clip section provided on a circle on the bottom surface of said frame. The frame and magnetic circuit are coupled together by the clip section and an extension provided along the outer circumference of the magnetic circuit. Despite a downsized magnetic circuit, the frame and the yoke can be coupled easily together in a loudspeaker in accordance with the present invention.

Abstract: A dual magnetic field speaker. The speaker includes two magnets, two yokes, two plates, and a voice coil having an upper winding and a lower winding disposed in an air gap. The speaker generates a constant intensity of magnetic flux that produces two monostable magnetic fields.

Abstract: The disclosure relates to electroacoustic receivers of the type which incorporate a reed armature. Thus, a receiver comprises a coil, magnets, pole pieces and a reed armature which passes through a central tunnel defined by the coil. A central portion of the reed lies within the tunnel. The coil includes a predetermined winding for decreasing the parasitic capacitance of the coil.

Abstract: A compact lightweight speaker system without a resonance box that can reproduce the original sound with high fidelity. A speaker unit is located on a baffle board with a vibration absorbing member between a frame of the speaker unit and the baffle board. Furthermore, an acoustic resonance reflecting board of a vertical flat board type based on the operating principle of a passive radiator is formed by the baffle board and a flat board being similar to the baffle board. As a result, a compact smart design will be produced. It is applicable to an electric or electronic apparatus which produces sound.

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: Fixing of a voice coil 16 to a diaphragm 12 is performed by caulk-fixing a coil supporting member 26 to the diaphragm 12 and by fit-supporting the voice coil 16 by the coil supporting member 26. Hereby, the voice coil 16 is physically fixed to the diaphragm 12 and its fixing strength is heightened. The caulk-fixing is performed by subjecting a caulking projection of the coil supporting member 26 to a plastic deformation thereby to provide a caulk-fixed portion 26b, whereby deformation injurious to the acoustic property does not occur in the diaphragm 12. Further, the fit-supporting is performed by interposing a flange portion 16a1 formed at an upper end portion 16a of the voice coil 16 between an engaging engaging portion 26a of the coil supporting member 26 and a central flat portion 12b of the diaphragm 12 and holding it by them from upper and lower sides.

Abstract: A loudspeaker comprises a frame mounted to a motor structure, an upper suspension connected between the voice coil of the motor structure and the frame, and, a lower suspension extending from the voice coil to the frame in position to form a cavity between the top plate of the motor and the lower suspension. The frame includes a bottom plate having a number of spaced vanes which rest atop the top plate of the motor and form passages therebetween through which a comparatively high volume of air is circulated at relatively high velocity in and out of the cavity between the lower suspension and lower end of the frame in response to excursion of the voice coil during operation of the speaker. The passages are positioned to direct such air flow over the top plate, and in some embodiments along at least a portion of the voice coil, to aid in cooling of these elements.

Abstract: This invention is intended to provide a wax excellent as a surface treating agent, a copper foil flexible wire capable of accommodating with flame resistance, and a speaker using this flexible wire. It is characterized in that petroleum wax is mixed with 50 wt %-150 wt % of liquid phosphoric ester flame retardant. In case of forming this flexible wire constituted by a plurality of core wires (8), each of which is wound by copper foil (9) and braided together or stranded, and then impregnated with the wax in order to form a wax layer (10), it realizes to provide a highly flame resistant flexible wire which satisfies the UL Standards 94V-2 or higher level without degrating its flexibility.

Abstract: Disclosed is a vibration apparatus capable of generating both a sound wave and a vibration with a simple structure due to the fact that a driving control section selectively supplies a current relying upon a kind of frequency of the current inputted from the outside. If a high frequency current is inputted into the driving control section, because a vibrating body vibrates up and down by interaction between a magnet and a pair of vibrating coils which are disposed in a side-by-side relationship such that they are opposite to the magnet, a sound wave is generated whereby it is possible to notify of reception of an incoming call by the sound wave.

Abstract: An electro-acoustic speaker having no permanent magnet. An audio input signal is applied to a pair of parallel coils, each being in series with a diode. The diodes are oppositely acting, so that the coils conduct during alternate half cycles of the input signal. As a result, the coils alternately generate magnetic flux for cooperative establishment of an unidirectional magnetic field. The input signal is also applied to a third coil for generation of a full wave current therethrough. This full wave current produces magnetic flux which establishes an alternating magnetic field. Interactions between the current-carrying coils and their respective magnetic fields produce acceleration forces for a speaker cone.

Abstract: An ultrasonic emitter device having broad frequency range capacity with relatively large diaphragm displacement compared to typical electrostatic diaphragm movement. The device includes a core member able to establish a first magnetic field adjacent the core member and a movable diaphragm stretched along the core member and displaced a short separation distance within a strong portion of the magnetic field. At least one, low mass, planar, conductive coil is disposed on the movable diaphragm and includes first and second contacts for enabling current flow through the coil. A variable current flow to the at least one coil provides a second magnetic field which variably interacts with the first magnetic field to attract and repel the diaphragm at a desired frequency for development of a series of compression waves which may be adjusted to include an ultrasonic frequency range.

Abstract: A speaker apparatus has a damper for supporting vibrating elements including a vibrating diaphragm. The damper is formed by injecting a predetermined amount of a resin material into a metal mold of an injection molding equipment.

Abstract: Voice coil assemblies are designed so that the solder points which connect the coil wires and the stranded wires, are connected via a separate adhesive seam to the diaphragm or the voice coil carrier. According to the invention, the solder points are placed in the adhesive seam by which the centering membrane is connected to the voice coil carrier. The first region of the centering membrane is designed to be open in the direction of the voice coil. By locating the solder points in the adhesive seam a voice coil assembly is created which is distinguished by a low design height, a good current-carrying capacity and an excellent height reproduction.

Abstract: A small, compact subwoofer cabinet; openings in two cabinet walls; first and second cages mounted on respective ones of the walls in alignment with the openings; a voice coil driven driver including an annular magnet weighing approximately 225 oz affixed to the first cage; a stationary pole piece extending through the magnet and defining a magnetic gap therebetween; a voice coil mounted on a cylindrical voice coil former positioned within the gap; a cone affixed to one end of the former; a first flexible surround secured to the outer end of the cone and to the first cage; a flexible spider secured to the former and to the first cage; a mass driven driver including a mass aggregating about 2 lbs; a second flexible surround secured to the mass and to the second cage; a flexible spider attached to the second cage and to the mass; both surrounds having a thickness of about 0.1", an edgeroll having a diameter of about 1.5", and capable of standing off internal pressures of up to about 3 lbs/in.sup.

Abstract: A voice coil adaptor ring and loudspeaker system of the moving coil type including a cone diaphragm supported by a frame, a voice coil former for supporting a voice coil, and a lower suspension for securing and centering the voice coil former in a magnetic gap while it is displaced by a magnetic circuit. The voice coil adaptor ring is mounted over the voice coil former and comprises a substantially cylindrical sleeve having at least one ledge extending outward from said sleeve for supporting the cone and lower suspension and a plurality of venting passages in fluid communication with a cone volume defined by the cone for venting hot air from the cone volume.

Abstract: This invention is intended to provide a wax excellent as a surface treating agent, a copper foil flexible wire capable of accommodating with flame resistance, and a speaker using this flexible wire. It is characterized in that petroleum wax is mixed with 50 wt %-150 wt % of liquid phosphoric ester flame retardant. In case of forming this flexible wire constituted by a plurality of core wires (8), each of which is wound by copper foil (9) and braided together or stranded, and then impregnated with the wax in order to form a wax layer (10), it realizes to provide a highly flame resistant flexible wire which satisfies the UL Standards 94V-2 or higher level without degrating its flexibility.

Abstract: A broad band loudspeaker (101) includes a diaphragm (103) driven by coil assembly (125) centered on a pole (131) of a magnet assembly (133) by a low-friction guide (127) depending from a lower end the coil assembly, and a low-friction guide mounted on an upper end of the pole (131). A suspension (107) for the diaphragm (103) includes two or more parallel, resilient suspension members (115a, 115b), extending between the diaphragm (103) and frame (105) and mounted through a pair of resilient mounting pads (119a, 119b, 125a, 125b). The lower guide (127) includes a flexible portion (151a) which acts like a flapper valve of a pump to create a current of cooling air past down the inside of the coil assembly (125), up the outside of the coil assembly and then out of flux gap (130).

Abstract: In an electroacoustic transducer (1) including a substantially hollow cylindrical magnet system (9) which is substantially centro-symmetrical with respect to a transducer axis (2), a diaphragm (17) and a voice coil (16) connected to the diaphragm (17) having two coil leads (20), and two contact terminals which, viewed in the direction of the transducer axis (2), are disposed inside the magnet system (9) and are each connected to one coil lead (20), the contact terminals are spring contacts (21, 22) which are formed with at least one bend and are preferably U-shaped, having two limbs (23, 24) extending transversely to the transducer axis (2) and including a first limb (23), which is mechanically connected to a contact holder (26) of the transducer (21), and a second limb (24) having contact faces (25) which are movable parallel to the transducer axis (2), the contact faces (25) of both spring contacts (21, 22) having different radial distances from the transducer axis (2).

Abstract: A speaker has electrical insulation between the voltage found on the voice coil and the exposed support frame. The insulation can be in the form of a toroid, a washer or a plurality of spacers with opening therebetween spaced so as to maintain electrical separation between the frame and magnet/pole piece.

Abstract: The present invention provides an electroacoustic transducer which realizes an optimum characteristic thereof utilizing heat caused by reflow soldering without being influenced by the same heat. The electroacoustic transducer includes a magnetic driving portion composed of a base, a core provided upright on the base and a coil wound around the core, wherein a height of the coil at the manufacturing time is set lower by a height which corresponds to thermal expansion of the coil in reflow soldering, and a projection length of the core exposed from the coil at the manufacturing time is set larger by the height which corresponds to thermal expansion of the coil in reflow soldering.

Abstract: A spacer for mounting around the outer peripheral surface of a bobbin. The spacer has first and second edge surfaces formed in a circular arc shape. Subsequent to the formation of a first coil by winding wire around the bobbin, the wire is continuously curved from a distal end portion of the first coil along the first edge surface of the spacer. After making a U-turn of substantially 180 degrees, the wire is wound to form the second coil. Upon completion of winding of the second coil, the wire is guided along the second edge surface, from an end portion of the second coil, and a second portion of the first coil is wound. The portion of the wire for connecting both of the first and second coils is free from bent corners, thus avoiding the generation of stress concentration. Also, the wire is guided by smooth and curved edge surfaces of the spacer, thus preventing damage to a coating on the wire.

Abstract: A tinsel cord support member 30 is formed on a gasket 24, two grooves for supporting tinsel cords 26 and conducting them from a tip end portion of the tinsel cord support member 30 up to near terminal lugs 28 are formed at predetermined intervals from each other in the tinsel cord support member, and a hollow portion 30a is provided between the two grooves formed in the tinsel cord support member 30.

Abstract: The present invention provides an electroacoustic transducer and a method of fabricating the same, employing a lead frame to integrally form a plurality of component parts, thus reducing the number of individual component parts, and improving assembly efficiency. The electroacoustic transducer comprises a base, a yoke fixed to the base, a core, a coil wound around the core, magnet surrounding the coil, a support ring surround the magnet, a vibrating plate supported on the support ring, lead terminals fixed to the base, and a case having a sound emitting cylinder and joined to the base so as to cover those components. A gap is formed between the core and the diaphragm. The diaphragm, the gap, the core, the yoke and the magnet form a closed magnetic path. The coil drives the diaphragm for vibration when energized. The yoke and the lead terminals are integrally formed of a common metal material such as the lead frame. The core may be integrally formed with the yoke of the lead frame.

Abstract: The present invention provides a fabrication method of an electroacoustic transducer capable of simplifying an assembling process on a lead frame and realizing an automatic assembly. The method comprises steps of forming pole piece portions, forming a lead frame having a plurality of base forming areas thereon, each of the areas having lead terminals formed therein, forming bases of a synthetic resin on the lead frame by molding so that the pole piece portions are embedded in the bases, mounting a coil on the pole piece portions embedded in the bases, disposing a support ring and a magnet so as to surround the coil, and placing a diaphragm on the support ring to be held thereby, connecting opposite ends of the coil to the lead terminals, cutting off the lead terminals from the lead frame, putting cases on and fixedly joining the same to the bases, and subjecting the cut lead terminals to a forming process.