Abstract: A panel-form loudspeaker includes a radiating panel, a frame, a suspension unit, a transducer and a linkage unit. The frame is used for supporting and positioning the radiating panel. The suspension unit is disposed between the frame and the bottom periphery of the radiating panel, and is made of a soft material. The transducer includes a voice coil unit and a magnet unit. The voice coil unit is coupled to the radiating panel at a specific location under the radiating panel. The linkage unit includes a first linking portion coupled to the frame, a second linking portion coupled to the voice coil unit via a resilience support, and a third linking portion coupled to the magnet unit.

Abstract: A planar diaphragm loudspeaker for use in a suspended ceiling grid and related methods of manufacturing are provided. The loudspeaker includes a rectangular, planar diaphragm of polymer material sized to fill an opening of the ceiling grid. The front surface of the diaphragm defines a three-dimensional, textured pattern formed by a secondary operation, such as, etching, perforating, and adhesion of granular or fiber material. The diaphragm may include an outer region about the periphery of the diaphragm having a density of at least 5 pcf and an inner region circumscribed by the outer region, thereby providing sufficient structural stiffness to the outside perimeter of the diaphragm and eliminating the need of an outer frame. The density of the inner region is at or below about 3 pcf throughout the inner region. Also, a shroud may secured to the diaphragm, in which the shroud and the diaphragm are securable in a first orientation for flush mounting or in a second orientation for tegular-drop mounting.

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: A loudspeaker diaphragm affixed with a coil includes an edge portion located outside of a portion affixed with the coil and a center portion located inside of the portion affixed with the coil. The center portion is provided thereon with ribs. With these ribs, the height of the center portion can be limited to the height of the ribs. 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; 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: Acoustic device including a member extending transversely of its thickness and capable of sustaining bending waves at least over an intendedly consequentially acoustically active area of the transverse extent of said member, the member having, by reason of orderly design methodology disclosed and claimed, a distribution of resonant modes of its natural bending wave vibration at least over said area that is dependent on values of particular parameters of said members, including geometrical configuration and directional bending stiffness(es), which values have been selected to predetermine said distribution of natural resonant modes being consonant with required achievable acoustic action of said member for operation of said device over a desired operative acoustic frequency range.

Abstract: A planar type speaker keeps its diaphragm (2) free from any distortion in operation, thus providing high fidelity sound reproduction. The diaphragm (2) is of a planar type and surrounded by a flexible edge member (3). This member (3) is constructed of an inner edge piece (3a) and an outer edge piece (3b) each of which has a semicircular shape in cross section to provide a convex surface and a concave surface. These edge pieces (3a, 3b) are the same in construction, but are inverted in arrangement to have the concave surfaces thereof face to each other to sandwich the diaphragm (2) between the concave surfaces of the edge pieces (3a, 3b); and, the outer edge piece (3b) is provided with a plurality of notched holes (7) which are symmetrically arranged in the outer edge piece (3b).

Abstract: A piezoelectric electroacoustic transducer includes a substantially rectangular piezoelectric diaphragm having an internal electrode, a plurality of laminated piezoelectric ceramic layers having the internal electrode interposed between two of the piezoelectric ceramic layers, principal-surface electrodes disposed on top and bottom principal surfaces of the piezoelectric diaphragm, the piezoelectric diaphragm generating surface bending-vibrations in response to application of an alternating signal between the principal-surface electrodes and the internal electrode, a resin film that is larger than the piezoelectric diaphragm and having the piezoelectric diaphragm affixed onto substantially a central portion of a front surface thereof, and a housing having a support for supporting the outer periphery of the resin film.

Abstract: A tweeter with a light, thin sandwich plate which can be excited into multiple reflected bending waves, and a driver which makes a vibrating contact and excites the sandwich plate, where the driver is designed for higher sound frequencies and the sandwich plate for propagating bending waves with low damping. The sandwich plate is freely carried with low damping by holding elements, where the latter are designed to be low damping at higher sound frequencies.

Abstract: An audio speaker including a chassis and a diaphragm defining an axis. A suspension movably interconnects the diaphragm and the chassis for reciprocating movement of the diaphragm along the axis. A motor is operably connected to the diaphragm for powered movement thereof. The diaphragm includes a cylindrical flange extending from its peripheral edges axially in the direction of the motor. The termination of said cylindrical flange provides an attachment for an annular rear flexible suspension member that, in turn, attaches to the frame.

Abstract: A magnetic circuit for a speaker comprises: a bonded magnet shaped rectangular in top plan view, having on its top face a plurality of grooves formed to extend all the way along two opposing sides thereof and arrayed in parallel with one another at predetermined intervals, and magnetized such that magnetic fluxes at two adjacent grooves are directed inversely to each other; and a plurality of plate-like pole pieces fixedly disposed on the top face of the bonded magnet, and arrayed along the grooves such that two adjacent pole pieces form an air gap located along the center of each groove thereby forming a magnetic gap. And, there is provided a speaker which uses the magnetic circuit thereby achieving a reduced profile.

Abstract: A plane driving type electroacoustic transducer having a film of diaphragm with a conduction pattern formed thereon and a magnetic circuit, wherein a vibration damping layer is provided on the diaphragm.

Abstract: A speaker unit is fitted to a speaker-unit mounting hole of a baffle plate provided with the speaker-unit mounting hole. The speaker unit is fitted to at least one of service holes provided in a door panel (inner panel) of a door apparatus for a vehicle.

Abstract: The invention relates to the embodiment of so-called panel loudspeakers working according to the bending wave principle. Said panels are generally formed by a panel (11), at least one driver (12) and a frame (13), the panel (11) being connected to the frame (13). In order to achieve appropriate bending wave induction in the panel (11), very complicated assessments must be made in order to determine the corresponding positioning areas (15) in which the driver (12) excites the panel (11) or is connected to the latter. Furthermore, the size of the panels (11) can change considerably depending on the application so that assessments must only be made repeatedly in the case of panels that can be easily modified. The invention aims at providing general positioning areas (15) for the driver (12) in or on the panels (11) so that no further assessments need to be carried out regarding the positioning area (15).

Abstract: The assembly comprises a loudspeaker drive unit having terminals for connection to an audio signal source. The drive unit has a chassis with a mounting ring which has first and second opposed surfaces for, respectively, abutment against a seating in a mounting ring and abutment by a retaining circlip. The mounting ring is retained in an aperture in, for example, a ceiling by spring clips. The design of the drive unit allows it to be substituted for the sealed halogen light bulb in a conventional light fitting having such a bulb. A simple and convenient way of mounting the loudspeaker, particularly in a ceiling in a room such as a kitchen or bathroom where space elsewhere is limited, is therefore provided. The invention also facilitates conversion between a light fitting to a speaker installation.

Abstract: To provide a piezoelectric speaker in which a breakdown of an electric lead terminal due to a large amount electric current flow is prevented an electric accident due to hand touch to an electrode and a frame is prevented, the precision of position and shape of the electrode formed by masking is enhanced, and the generation of buzz sound that becomes noise is prevented, side frames fixing side ends of a vibrating diaphragm are sectioned into upper and lower plates by the side ends formed in a corrugate shape, and a vibrating diaphragm supporting portions of the upper and lower plates are formed in the same corrugate shape as that of the side ends so that the side ends are clamped by the vibrating diaphragm supporting portions in the state of the corrugate shape of the vibrating diaphragm being maintained, and partitioning plates are inserted between the side frames to partition crests and troughs of the vibrating diaphragm.

Abstract: An electro-acoustic transducer (1) is proposed for a component operating with surface waves, in particular for a surface wave filter, in which, to suppress interfering excitation ensuing in the gap region, a variation of the gaps (4) is implemented with regard to at least one feature selected from transversal arrangement, size and shape. Due to the slight dimension change (&Dgr;D) in comparison to the finger length, the desired primary excitation in the transducer remains approximately unchanged, however the interfering excitation is displaced or divided, and therewith made ineffectual.

Abstract: This disclosure is directed to flat panel speakers in which an exciter is mounted at a non-zero angle relative to a flat panel. For example, a mounting bracket can be attached to the flat panel, and the exciter can be mounted on the mounting bracket such that the exciter is rotated at relative to the flat panel. By mounting the exciter at a non-zero angle relative to the flat panel, less surface area of the flat panel is consumed by the presence of the exciter. Accordingly, flat panel speaker designs as described in this disclosure are particularly useful when the surface are of the flat panel is also used for other purposes.

Abstract: A loudspeaker comprising a panel which is sufficiently stiff to support bending waves, the panel having a boundary, a transducer mounted to the panel to apply bending wave energy in the form of dispersive travelling waves thereto at a first location in response to an electrical signal applied to the transducer to cause the panel to vibrate and radiate an acoustic output, the loudspeaker having a frequency range extending from a lower frequency to a higher frequency and the panel having a stiffness giving a coincidence frequency above the lower frequency. Means on or associated with the panel at a second location attenuates travelling bending waves in the panel to prevent or at least substantially to moderate panel resonance.

Abstract: A two-way communication device comprises a magnetoelastic rod (4) located between an inertial back mass (8) and a front panel (6) of low mass. A coil (13, 5) located in the vicinity of the rod (4), and the rod and coil together defining an audio-electric transducer. Electronic processing means ensures that an audio-electric signal input to the device is applied to the coil (13, 5) a sound wave is produced from the low mass panel (6) and when a sound wave impinges on the low mass panel (6) an audio-electric signal is produced which is output from the device.

Abstract: A panel-form loudspeaker includes a radiating panel, a frame, a suspension unit, a transducer and a linkage unit. The frame is used for supporting and positioning the radiating panel. The suspension unit is disposed between the frame and the bottom periphery of the radiating panel, and is made of a soft material. The transducer includes a voice coil unit and a magnet unit. The voice coil unit is coupled to the radiating panel at a specific location under the radiating panel. The linkage unit includes a first linking portion coupled to the frame, a second linking portion coupled to the voice coil unit via a resilience support, and a third linking portion coupled to the magnet unit.

Abstract: A compilation of improvements and modifications to U.S. Pat. No. 5,392,358 which discloses an electrolytic loudspeaker assembly (10) which reproduces a broad band of audio signals. The assembly (10) is comprised of a thin, non-magnetic capacitive transducer (12) which consists of compound diaphragm (14) that is further comprised of a center section (16), a front section (20) and a rear sect compound diaphragm (14) is enclosed by a frame assembly (32). The improvements and modifications to the assembly designs for a center section (16A, 18A); three designs each for a front section (20A, 24A, 28A) and a rear section (22A, 26A, 30A); three designs for a frame assembly (32A, 34A, 36A) and two designs for a transducer driver unit (46, 48). The basic design of the assembly (10) is also augmented by the addition of an acoustic wave diffuser, reflector, and absorbing assembly (40) and an acoustic baffle structure (44).

Abstract: A loudspeaker system comprising a closed cabinet containing a tuned port, an electromechanical driver, an acoustic radial transmission line (VARTL), a reactive alternate density transmission medium (ADTM) load and a radial right angle wave guide (RRAWG). The VARTL is disposed around and in front of the cone of the driver so as to isolate the driver from reflected signals it produces, while simultaneously allowing the driver to remain inert to the reflected signals, acoustic summation or stimulus. The ADTM slows the speed of the wave, thereby causing delay and intentional attenuation of the initial waveform while, by way of radial expansion, allows the proper exit velocity. This system allows the cone to drive the port air mass and the VARTL air mass with essentially equal pressure on each cycle throughout the frequency range of the VARTL and substantially reduces mechanical vibrations in the cabinet by effecting balanced pressures.

Abstract: The disclosure relates to an in-wall speaker system, specifically a system that is not readily visible and mounted in a room. The in-wall speaker system is comprised of a base frame is adapted to be mounted between support members of a wall. The in-wall speaker system further has a speaker assembly mounted to the base frame and an active member that has an outer surface which is substantially coplanar with the surrounding wall section and in one form extends slightly outward therefrom. The base frame, speaker assembly, and the active member cooperate to form an acoustic chamber that is positioned behind the inner surface of the active member. Acoustic energy is transferred from the speaker assembly to the active member where the sound is produced therefrom to the room.

Abstract: A panel transducer includes a diaphragm with areas of multiple electrical conductors, two rows of magnetic bars, two metal plates and a clamping frame. The diaphragm is clamped in the clamping frame and is positioned between the two rows of magnetic bars. Each row of magnetic plates is in close proximity to the clamped diaphragm. Each metal plate has holes. The holes correspond to spacing areas between the magnetic bars and acoustically connect the diaphragm to outside media. The magnetic bars are sequentially located on the metal plates with spacing between the magnetic bars. The diaphragm is secured to the clamping frame and has an active surface area under tension spaced inwardly of the clamping frame. There are no side magnetic bars at the ends of each of the row. Absorbing strips are used in place of the absent magnetic bars filling the space between the side magnetic bars and the clamping frame.

Abstract: A wall mounting speaker assembly having a speaker unit, includes a stationary member mounted on a wall; a supporter supporting the speaker unit; a movable joint provided between the stationary member and the supporter, and combined with a vertical swiveling shaft and a horizontal tilting shaft, which make the speaker unit swivel and tilt; a lock provided on a bottom of the speaker unit; and a hook provided on the supporter to be engaged with the lock, preventing the speaker unit form moving upward. With this configuration, the present invention provides a wall mounting speaker assembly which can mount a speaker unit with a simple and convenient setup method without a screwing work, and has swiveling and tilting functions.

Abstract: To achieve a large thickness of conductive metal-containing material in a feature of a product unit processed with a liquid-based etch process, the desired thickness of material is apportioned to the two opposing surfaces of a substrate to create a two-part feature. Conventional features are made by identically patterning two same-thickness metal-containing layers and electrically connecting the resulting patterned parts in any suitable manner. However, features may also be made that do not have identical parts on opposite sides of the substrate, the two parts being electrically connected but differing in thickness, in shape, or both. Moreover, having two metal-containing layers separated by an insulator is also useful for allowing different sections of the same feature or circuit to cross one another without shorting, or to overlap in whole or in part without shorting.

Abstract: Ring magnets (5) are concentrically placed with certain spacings (6) on a magnetic frame (4). The magnetic members on the magnets (5) are removed, and the magnets are arranged so that the polarities of adjacent magnets (5)are alternately opposite to each other, thus forming a magnetic circuit. Ribs (7) are provided to a planar vibrating plate (1) and a voice coil (2) fabricated by vertically stacking conductive wires annularly is attached to the planar vibrating plate (1). The planar vibrating plate (1) is secured to a frame (4) through a gasket (3). The voice coil (2) is inserted into magnetic gaps of spacings (6). Since no magnetic body is placed over the magnets (5), the height of the magnetic circuit can be low, and an increase of the reactance due to provision of the magnetic body of the voice coil (2) does not occur. Since the rigidity of the planar vibrating plate (1) is high, it is unnecessary to secure the planar vibrating plate (1) to the frame (4). while applying a tension.

Abstract: An advanced design for an electrostatic and an electrolytic loudspeaker assembly (10) that comprises a compound diaphragm (12) sandwiched between a first metal stator (40) and a second metal stator (60), wherein each stator includes a multiplicity of perforations (41,61). All the sides of the stators (40,60) as well as the inside surface of the perforations (41,61) are coated with an insulating material (90) also known as ACOUSTAGUARD™ (90) which includes a base coat (92) and a sealing and pigmentation coat (94). The coats (92) and (94) are applied by a unique process that allows ACOUSTAGUARD™ to be applied at room temperature by preferably a spraying technique. The application of ACOUSTAGUARD™ avoids any arcing or corona discharge between the two stators (40,60) which can distort the audio output and damage the loudspeaker assembly (10).

Abstract: A speaker apparatus in which the acoustic sound is radiated by flexural oscillations of a diaphragm in the form of a panel having a substantially flat surface. The speaker apparatus includes a panel-shaped diaphragm the outer rim of which can be oscillated substantially freely at least in the direction along the diaphragm thickness and at least one driver unit constituting an oscillation source secured to the diaphragm surface for imparting oscillations to the diaphragm. The diaphragm is set into flexural oscillations by oscillations applied from the driver unit driven on the basis of the playback input signal. By flexurally oscillating the diaphragm to radiate the acoustic sound, optimum frequency response characteristics can be obtained over a wide frequency range from the low to high frequency range. Moreover, the acoustic sound of optimum sound quality may be radiated in a state of minimum sound pressure level fluctuations over a frequency range from the low to high frequency range.

Abstract: A loudspeaker is made of a panel supporting bending waves and a transducer covering a substantial portion of the panel surface. At least one constraint, for example a clamp or a mass, is fixed to the panel. Each constraint reduces the mobility of a small area of the panel. Excitation of the transducer excites bending waves in the panel; the constraints discourage simple motion and encourage the production of a plurality of bending waves instead. The constraints can constrain the panel to be excited to produce a good distribution of resonant bending wave modes.

Abstract: The present invention relates to a LCD display that has a thin depth, rigid enclosure and includes a thin speaker so that the depth of the enclosure does not have to be increased to accommodate the speaker. The speaker is used to generate audio output that may correlate to the graphical information displayed on the LCD display. The enclosure has an opening for inclusion of a semi-rigid lens for viewing of an internal LCD module that is also used as a planar surface for the thin speaker. In order to provide a thin device in the enclosure that is driven by a driver to move air to generate sound, the driver is attached to the semi-rigid lens.

Abstract: An information processing device and a speaker unit applicable to the device. In one aspect of the present invention, the device includes a housing, a pole piece, a voice coil, a magnet, and a frame. The housing has an elastically vibratory vibration region. The pole piece has a first end and a second end. The first end is fixed to the vibration region of the housing. The voice coil is fixed to the second end of the pole piece. The magnet forms a magnetic field interlinking the voice coil. The frame fixes the magnet to the housing at a region other than the vibration region, for example. With this configuration, vibration of the voice coil due to a current flowing through the voice coil is transmitted through the pole piece to the vibration region of the housing, thus eliminating the need for a vibration board of a speaker and further eliminating the need for formation of holes for sound transmission through the housing.

Abstract: A mid and high frequency transducer having a compact magnet system. A first seat has an annular wall that retains a first disk shaped magnet therein and an annular channel is defined therebetween. A second seat rests on top of the first magnet and first seat and is connected thereto but does not occlude the annular opening. The second seat has an annular wall that retains a second disk shaped magnet therein such that a uniform annular gap is defined therebetween. A first voice coil is connected to a first diaphragm and is moveably suspended within annular channel and a second voice coil is connected to a second diaphragm and is moveably suspended within the annular gap. Application of an electric current to the voice coils causes movement of the diaphragms due to the magnetic flux created within the annular channel and gap and thereby produces sound waves.

Abstract: A fire protective flat panel radiator assembly for installation in a suspended ceiling grid is provided. The assembly includes a flat panel radiator having a frame that supports a sonic diaphragm, which is driven by a transducer to reproduce an audio program. A back box is mounted to the radiator and the back box covers and encloses the diaphragm and other fire susceptible components of the radiator. The back box is provided with a cut-out portion that is covered with an air pervious panel, which is resistant to fire hazards but that allows air flow in and out of the back box. In one embodiment, the radiator has a bridge and the back box is formed by a pair of shells mounted on each side of the bridge to enclose and protect the diaphragm. The result is a fire protected flat panel radiator assembly that meets the fire performance requirements for air handling plenums while retaining the sonic fidelity of a flat panel sound radiator without a fire protective back box.

Abstract: A system responsive to acoustic waves includes a resonator having a bottom plate, side walls secured to the bottom plate, and a top plate disposed on top of the side walls. The top plate includes an orifice. The bottom plate or side walls of the resonator include at least one compliant portion. A reciprocal electromechanical transducer is coupled to the compliant portion of the resonator to form a transducer/compliant composite, wherein the transducer/compliant composite has an open circuit acoustic impedance. An electrical network is coupled to the transducer/compliant composite. The acoustic impedance of the transducer/compliant composite copied to the electrical network is different as compared to the open circuit impedance which perm its the frequency response of the system to be varied over a large range of frequencies.

Abstract: The present invention provides an electroacoustic transducer capable of removing non-uniformity of a gap between a coil and a magnet and of vibrating a diaphragm properly, and an electronic apparatus using the same. An electroacoustic transducer 1 of the present invention comprises a plane diaphragm 2 and a vibration-generating source 3 for vibrating the diaphragm 2, wherein the vibration-generating source 3 is supported in the vicinity of one end 2a on the backside of the diaphragm 2, at least the one end 2a and two sides 2b and 2b of the diaphragm 2, which are perpendicular to the one end 2a and are opposite to each other, are supported on an elastic cushion member 9, and wherein the diaphragm 2 is vibrated in a plane direction perpendicular to the plane of the diaphragm 2 when the vibration-generating source 3 is driven.

Abstract: A method of improving the modal resonance frequency distribution of a panel (2) for a distribution resonant mode bending wave acoustic device involves analysing the distribution of the modal resonance frequencies of the panel, identifying a modal resonance frequency that is non-uniformly spaced relative to adjacent modal resonance frequencies, identifying a location on said panel that exhibits anti-nodal behaviour at said modal resonance frequency and changing the local impedance to bending wave vibration at said location (6). The method has particular application to distributed mode loudspeakers (1).

Abstract: A planar diaphragm loudspeaker for use in a suspended ceiling grid and related methods of manufacturing are provided. The loudspeaker includes a rectangular, planar diaphragm of polymer material sized to fill an opening of the ceiling grid. The front surface of the diaphragm defines a three-dimensional, textured pattern formed by a secondary operation, such as, etching, perforating, and adhesion of granular or fiber material. The diaphragm may include an outer region about the periphery of the diaphragm having a density of at least 5 pcf and an inner region circumscribed by the outer region, thereby providing sufficient structural stiffness to the outside perimeter of the diaphragm and eliminating the need of an outer frame. The density of the inner region is at or below about 3 pcf throughout the inner region. Also, a shroud may secured to the diaphragm, in which the shroud and the diaphragm are securable in a first orientation for flush mounting or in a second orientation for tegular-drop mounting.

Abstract: A loudspeaker, and particularly, a woofer, including a flat diaphragm transducer having at least one stator plate for carrying magnetic elements in close proximity to a low stiffness diaphragm wherein a piston-like motion of the diaphragm is achieved by creating pressure zones adjacent the diaphragm to improve an acoustic coupling and increase acoustic output for a given size of diaphragm by the provision of non-uniformly spaced openings in the at least one stator plate which are selectively spaced to control low frequency diaphragm resonance modes.

Abstract: A drive module for attachment to a rigid panel and adapted to apply bending wave energy at audio frequencies to the panel whereby the panel can radiate an audio output. The drive module has a housing adapted to be secured to the panel, at least one foot on the housing and adapted to fix the housing securely to the panel, an electro-mechanical transducer in the housing, a support for the transducer in the housing, the transducer being adapted to contact the panel to apply bending wave energy thereto when energized with an electrical audio signal, and an audio signal amplifier in the housing.

Abstract: The invention relates to a system with multi-mode radiator panels used to reproduce sound. The multi-mode radiator panels include at least one driver, a core layer and two cover layers connected to the core layer. The panels are typically mounted in a frame with attachments providing a connection between the frame and the unit formed of the core layer and the cover layers. To protect the system against overload and damage, the entire driver electronics is housed in a hermetically sealed air space located between the frame, the core layer and the attachments. The driver electronics includes a power amplifier powered by low-voltage power supply. The voltage supply may be buffered by a battery to keep the average power supplied to the electronics small, while still being able to reproduce infrequently occurring peak power events.

Abstract: A piezoelectric electroacoustic transducer eliminates the need for the interconnection between main surface electrodes and internal electrodes, and is capable of constructing a bimorph diaphragm using a simple connection structure. The piezoelectric electroacoustic transducer includes a laminated body formed by laminating two or three piezoelectric ceramic layers, main surface electrodes each provided on the top and bottom main surfaces, and an internal electrode provided between any adjacent two piezoelectric ceramic layers. In the piezoelectric electroacoustic transducer, all ceramic layers are polarized in the same direction with respect to the thickness direction, and by applying an alternating voltage across the main surface electrodes and the internal electrode, the laminated body generates a bending vibration in its entirety.

Abstract: A vibration speaker is configured to selectively supply an input current in accordance with the frequency of the input current in response to an incoming call, thereby allowing the incoming call to be recognized by sound or vibrations using a single element. The vibration speaker includes a hollow housing with open ends with a vibrating plate attached at one end a shield plate at the other end. A yoke is fixedly mounted to an inner peripheral surface of the housing by plate springs, and a vertically polarized magnet is mounted on the yoke. A voice coil having an upper end fixed to the vibrating plate has a lower end arranged adjacent to the magnet, and a vibration coil is mounted on the shield plate so as to face the magnet. Damping means at the inner peripheral surface of the housing provide damping to the plate springs, thereby reducing the amplitude of vibrations.

Abstract: A magnetic circuit for a speaker comprises: a bonded magnet shaped rectangular in top plan view, having on its top face a plurality of grooves formed to extend all the way along two opposing sides thereof and arrayed in parallel with one another at predetermined intervals, and magnetized such that magnetic fluxes at two adjacent grooves are directed inversely to each other; and a plurality of plate-like pole pieces fixedly disposed on the top face of the bonded magnet, and arrayed along the grooves such that two adjacent pole pieces form an air gap located along the center of each groove thereby forming a magnetic gap. And, there is provided a speaker which uses the magnetic circuit thereby achieving a reduced profile.

Abstract: A loudspeaker comprising at least one magnet 27, yoke 24 fixed to a bottom surface of the magnet, flat plate 26 fixed on an upper surface of the magnet, magnetic circuit 29 having magnetic gap 28 formed between the plate and the yoke, and flat diaphragm 23 provided with coil 21 disposed above the magnetic gap. The magnet has a width greater than that of the plate, and at least a part of the upper surface of magnet is exposed so that it faces directly to the diaphragm. According to the structure of the present invention, a larger volume magnet can be used without increasing a size of the magnetic circuit. Furthermore, as magnetic flux can be concentrated to an upper region of the magnetic gap, the magnetic circuit becomes efficient and compact. Thus a compact and high-efficiency loudspeaker for high frequency sounds reproduction can be provided.

Abstract: A speaker apparatus in which the acoustic sound is radiated by flexural oscillations of a diaphragm in the form of a panel having a substantially flat surface. The speaker apparatus includes a panel-shaped diaphragm the outer rim of which can be oscillated substantially freely at least in the direction along the diaphragm thickness and at least one driver unit constituting an oscillation source secured to the diaphragm surface for imparting oscillations to the diaphragm. The diaphragm is set into flexural oscillations by oscillations applied from the driver unit driven on the basis of the playback input signal. By flexurally oscillating the diaphragm to radiate the acoustic sound, optimum frequency response characteristics can be obtained over a wide frequency range from the low to high frequency range. Moreover, the acoustic sound of optimum sound quality may be radiated in a state of minimum sound pressure level fluctuations over a frequency range from the low to high frequency range.

Abstract: A system for tensioning a membrane within a frame for a loudspeaker or a microphone is characterized by a frame containing an opening, a membrane connected to an exterior surface of the frame and spanning the frame opening, and a tensioning device connected with the frame for deflecting a portion of the membrane within the frame opening. The tensioning device is compliant thereby allowing the membrane to exhibit a high degree of flexure both within and beyond a plane containing the membrane.

Abstract: A loudspeaker system comprises a flexible paper or plastics diaphragm 1 for displacing a quantity of a transmitting medium to generate sound, waveform-sampling circuitry for supplying a series of sample drive signals of varying amplitude indicative of the amplitudes of an electrical input signal having an audio waveform

Abstract: The present invention relates to a LCD display that has a thin depth, rigid enclosure and includes a thin speaker so that the depth of the enclosure does not have to be increased to accommodate the speaker. The speaker is used to generate audio output that may correlate to the graphical information displayed on the LCD display. The enclosure has an opening for inclusion of a semi-rigid lens for viewing of an internal LCD module that is also used as a planar surface for the thin speaker. In order to provide a thin device in the enclosure that is driven by a driver to move air to generate sound, the driver is attached to the semi-rigid lens.