Abstract: A speaker diaphragm includes a body vibrating to generate a sound, an edge fusion-bonded to an outer circumference portion of the body, a projection provided on an upper surface of the edge, and a gasket provided on a lower surface of the edge. The edge is made of material different from that of the body. The projection is made of material identical to that of the edge. The gasket is made of material identical to that of the body. A speaker including the diaphragm has waterproof property by itself.

Abstract: A simple structure will achieve dissipation of heat from the area inside a voice-coil bobbin and a diaphragm without a reduction in sound quality, in which a process for assembling a speaker device with high accuracy is performed in a simple operation. A speaker device comprises a recess-shaped frame 5 which supports, through an edge 9, a vibration system member 68 provided with a diaphragm 8 coupled to a voice-coil bobbin 6, and a magnetic circuit 4 which comprises an approximately ring-shaped magnet 2 and an approximately ring-shaped plate 3 which are mounted on a yoke 1 disposed in the frame 5, and a magnet gap 4g in which a voice coil 7 wound on a voice-coil bobbin 6 is disposed. In the magnetic circuit 4 a through hole 45 extending in the vibration direction of the diaphragm is fitted over a center boss 51 of a shape protruding from the bottom of the frame 5 in the direction of the sound emission, so that the magnetic circuit 4 is positioned and fixed with respect to the frame 5.

Abstract: A slender-type diaphragm longer in a longitudinal direction and shorter in a transversal direction in relation to the longitudinal direction, has a base member and a slant member. The base member has a pair of extending members provided in parallel in the longitudinal direction as facing each other, and a curved section that protrudes toward a first side of the diaphragm in a vibration direction of the diaphragm from a first plane that includes the extending members, the vibration direction being perpendicular to the longitudinal and transversal directions. The slant member has a slant surface in relation to the first plane and connected to the base member in a manner that the slant member surrounds the base member in a second plane parallel to the first plane, the slant member having a curved surface in a cross section thereof in relation to a cross section of the base member in the transversal direction.

Abstract: The present disclosure is directed to inventive methods and apparatus for a variable flux speaker subassembly for a loudspeaker. The variable flux speaker subassembly may contain at least one repositionable structure that is repositionable from at least a first position to a second position. The magnetic flux through a voice coil structure of the speaker subassembly is altered when the repositionable structure is moved from the first position to the second position.

Abstract: An electromagnetic transducer includes an electromagnetic dual-coil or multi-coil driver having at least one spacer member placed between at least two permanent magnets. The inclusion of at least one spacer member increases the axial dimension of the magnetic assembly of the driver so that the magnetic gaps in a dual-coil or multi-coil driver are moved farther apart than would occur with a corresponding electromagnetic driver using a permanent magnet instead of two permanent magnets separated by a spacer member.

Abstract: An audio amplifier, that includes a planar inductor structure that includes a first plurality of windings, formed on layers of a first circuit board and a second plurality of windings, formed on layers of a second circuit board. The planar inductor structure may further include a sense winding.

Abstract: An audio module used for a display device is disclosed. The display device has a display substrate. The audio module has a filter, an amplifier, and at least one output unit. The filter receives and filters an audio signal to generate a filtered signal. The amplifier is coupled to the filter and amplifies the filtered signal to generate an amplified signal. At least one output unit is coupled to the amplifier and plays the amplified signal in a predetermined way.

Abstract: A multifunctional electromagnetic transducer includes a bracket, a vibrating unit including a magnetic circuit part receiving in the bracket, and a plurality of helical wound springs assembled to the bracket for sustaining the magnetic circuit part. The magnetic circuit part defines a pole plate, a first magnet disposed at a center portion of the pole plate, and a plurality of second magnets surrounding the first magnet and forming a magnetic gap corporately with the first magnet. Each of the second magnets forms a receiving gap corporately with an adjacent second magnet. A voice coil is partially inserted into the magnetic gap.

Abstract: A shaker transducer is disclosed, which comprises a magnetic unit (1) composed of a magnet (3) disposed between a first polar plate (2) and a second polar plate (4) in such a way to generate a toroidal air gap (5). A sound coil (6) is disposed in the air gap (5) to move axially and a centering element (100) is fixed to the coil to maintain it centered with respect to the magnetic unit (1). A rigid element (10) comprising a shank (12) fixed to said cylindrical support (61) of the sound coil and adapted to be anchored to a surface to transfer the sound vibrations generated by the magnetic unit (1). The centering element (100) comprises a central cylindrical shank (101) fixed to the coil, a peripheral shank (102) fixed to the second polar plate (4) and a plurality of elastic spokes (103, 103?) disposed between said central shank (101) and said peripheral shank (102).

Abstract: A multifunctional vibrator includes a frame, a vibrating unit receiving in the frame and including a magnetic circuit part with a magnetic gap, a plurality of elastic members connecting the vibrating unit and the frame, and a voice coil partially inserted into the magnetic gap. Each elastic member includes a retaining portion assembling to an inner face of the frame, a connecting portion attached to the vibrating unit, and an elastic portion extending from the retaining portion to the connecting portion along a devious way. The elastic portion of elastic members includes a first arm capable of generating elastic deformation along a short axis direction of the vibrating unit and a second arm capable of generating elastic deformation along a long axis direction of the vibrating unit.

Abstract: A micro-speaker includes a yoke, a magnet assembly attached to the yoke, a voice coil, and a diaphragm connected with the voice coil. The yoke defines a bottom wall, and a number of sidewalls extending upwardly from the bottom wall. The magnet assembly includes a main magnet positioned on the bottom wall, and a number of secondary magnets positioned on tops of the sidewalls.

Abstract: A micro-speaker includes a frame, a yoke, a magnet, a diaphragm, and a voice coil. The yoke includes a base wall and a plurality of sidewalls defining a number of flat walls and a number of curved walls disposed at corners of the yoke. The flat walls define a number of first steps disposed at an upper level for engaging with the position blocks, the curved walls define a number of second steps disposed at a lower level for air leaking.

Abstract: An electromagnetic transducer includes a frame, a diaphragm including a top plate and a periphery portion surrounding the top portion and attached to the frame, a magnetic circuit part receiving in the frame with a magnetic gap, a voice coil partially inserted into the magnetic gap for driving the diaphragm, and an elastic member including a first arm attached to the diaphragm and disposed in a plane and a pair of second arms extending outwards from the first arm and attached to the frame. The second arm further defines a stress-releasing portion protruding outwards from the plane where the first arm is disposed in.

Abstract: A speaker unit includes a frame that secures a diaphragm of a speaker at an outer circumference of the diaphragm, a magnetic circuit, a first leg that extends from a portion of an inner wall of the frame in a vicinity of a front of the speaker to the magnetic circuit, and that secures the magnetic circuit to the frame, and a second leg that extends from a portion of the inner wall of the frame in a vicinity of a rear of the speaker to the magnetic circuit, and that secures the magnetic circuit to the frame.

Abstract: A speaker diaphragm is configured by a compound mixed with resin and bamboo fiber. The diaphragm satisfying the advantage of the bamboo fiber of high sound quality and a large degree of freedom in the setting of the characteristic value of the diaphragm and the advantage of the diaphragm made of a resin with improved humidity resistance reliability and strength, excellent external appearance, and enhanced productivity and dimension stability is obtained.

Abstract: The present invention relates to a loudspeaker in the acoustic field and the information communication field. The invention provides a loudspeaker that can realize a thinner size. To achieve this, the loudspeaker of the present invention is structured so that a part of a diaphragm is inserted to a dent or an opening formed at the center poles of a lower plate of a magnetic circuit. This structure allows the diaphragm to be stored within the height of the magnetic circuit, thus allowing the loudspeaker to have a thinner size.

Abstract: A speaker includes a base defining a pair of receiving cavities separated from each other in a longitudinal direction and an engaging portion disposed between the pair of receiving cavities, a pair of magnetic circuit systems received into the pair of the receiving cavities, a diaphragm attached on the base, a pair of voice coil members connecting with the diaphragm, and a suspension mounted on the base. The suspension defines a pair of separating portions separated from each other in a lateral direction. Each separating portion defines a fixing portion engaging with the engaging portion of the base, a pair of connecting portions extending from two ends of the fixing portion and towards the diaphragm, and a pair of supporting portions connecting with the connecting portion for engaging with the pair of voice coil members, respectively.

Abstract: A speaker and the like, which is capable of wideband reproduction by improving the bass characteristic, and which is suitable for size reduction, is provided. A housing (110) includes one main surface (111) having a polygonal shape, and an opening portion (112) in the one main surface. A diaphragm (120) is disposed in the opening portion so as to cover the one main surface, except for corner regions (115a, 115b, 115c, and 115d) which are areas in the vicinity of respective vertices of a polygonal shape of the one main surface. A driving unit (130) causes the diaphragm to vibrate so as to generate a sound corresponding to a signal inputted from an outside. A plurality of movable supports (140a, 140b, 140c, and 140d) is disposed in the respective corner regions, for supporting the diaphragm by joining the housing and the diaphragm such that the diaphragm is vibratable.

Abstract: A speaker is disclosed. A speaker includes a fixing part (500) fastened to a base frame; a motion part moved (400) with respect to the fixing part by an electromagnetic force; a vibration plate (200) that vibrates in communication with the motion part; and a guide member (800) provided between the motion part (400) and the vibration plate (200). Therefore, according to the present invention, a speaker capable of reproducing a high quality sound and high power with a slim design may be embodied.

Abstract: An electroacoustic transducing device comprising: a magnetic circuit having a yoke, a magnet, and a pole piece; a vibration system having a diaphragm and a voice coil; and a frame which holds the magnetic circuit and the vibration system. The voice coil is placed in a magnetic gap, and has lead wires of the voice coil which are drawn out from the voice coil at positions which are remote from the diaphragm. Openings for air forming for forming slack portions in the lead wires are drawn out from the voice coil and are disposed in the frame. The lead wires are adequately subjected to the wire laying process, and the audio performance is prevented from being lowered.

Abstract: A structure of a voice coil assembly includes a plate, a top board, suspending arms and fixtures. The plate has a top and two opposite sides. The top board is disposed on the top of the plate. The suspending arms extend from the two sides of the plate and are connected to the fixtures. A pair of resilient sections is provided between the suspending arms and the fixtures. The resilient sections are formed in a curved, arcuate or wavy shape. The suspending arm has a cross-section in a flat shape.

Abstract: An electroacoustic transducer of the present invention includes a diaphragm 3 having a periphery as a fixed end, a coil 4 having an axis perpendicular to the diaphragm 3 and 6 attached centrally to the diaphragm 3, and a direct current magnetic field generator fixed in position as spaced apart from the coil 4 by a gap provided axially of the coil 4. The diaphragm 3 is driven by applying to the coil 4 a magnetic flux emitted from a surface of the direct current magnetic field generator that faces the coil 4. The direct current magnetic field generator includes a ring-shaped outer magnet 5 located coaxially with the axis of the coil 4 and magnetized in the direction perpendicular to the axis, and an inner core 6 including a ferromagnet and located in the central hole of the outer magnet 5.

Abstract: A thermal management system improves thermal property of the speaker system by promoting air circulation to cool the speaker system. The thermal management system includes a speaker frame, an air guide formed on the speaker frame for guiding the air, a ventilation slit formed on the air guide which penetrates through the speaker frame for air communication, and a spider mounting ring for mounting a spider of the speaker system on the speaker frame. The spider mounting ring has a cut-out at its upper edge which positionally match the air guide. The cut-out is curved sharply at its upper surface while a lower edge of the spider mounting ring is gently curved, thereby creating an air passage of directional property.

Abstract: The present invention relates to a damper of a rectangular-shaped slim speaker that is capable of preventing a vibration plate having an entire outer appearance of a slim oval/track-like shape extended to any one side thereof from being moved in forward and backward directions. The damper of a rectangular-shaped slim speaker includes: fixed end portions formed on either end thereof, respectively, to face each other in a vertical direction; support plate portions each extended backwardly from the fixed end portions; and an elastic portion extended backwardly from the support plate portions, wherein the fixed end portions, the support plate portions, and the elastic portion are formed integrally as an injection molded plastic product.

Abstract: An audio speaker with at least two electric coils on opposite sides of at least one ferro-magnetic plate, the coils and plate forming a radial electro-magnet. A radial electro-magnet can offer many advantages in stereo loudspeakers. The coils are electrically driven in opposite directions. Multiple sets of two coils and intervening ferro-magnetic plate may be provided, adjacent sets being separated by a non-magnetic plate.

Abstract: A speaker device includes: a magnetic circuit which includes two magnetic gaps; a diaphragm which is arranged at a position passing through at least the two magnetic gaps and includes a recessed part extending in a direction substantially orthogonal with respect to an extending direction of a magnetic flux in the magnetic gaps; and a voice coil, formed into an annular shape, which includes a first parallel part extending in one direction and a second parallel part extending in a direction in parallel with the first parallel part and opposite to the first parallel part with a constant space. Particularly, the first parallel part and the second parallel part are arranged in a direction in parallel with an extending direction of the recessed part, respectively, and the first parallel part and the second parallel part are arranged in the recessed part to be positioned in the two magnetic gaps, respectively.

Abstract: A loudspeaker provides increased magnetic flux from multiple magnets to drive voice coils to generate sound. The loudspeaker is formed as a smaller profile and reduced weight package. The loudspeaker includes a dual pole, first and second magnets, first and second front plates, and first and second gaps. The polarities of the first and second magnets are aligned in the same direction. The first and second magnets may be disk or ring-shaped and may be coupled to a flange of the dual pole. The first and second gaps may be formed between the inner diameters of the first and second magnets and the dual pole. The magnetic flux produced by the first and second magnets may be combined, directed, and concentrated within the first and second gaps by the dual pole and the front plates. At least portions of a first and a second voice coil may be positioned within the first and second gaps, respectively, and diaphragms may be coupled to the first and second voice coils.

Abstract: A low profile miniature speaker configured for use in greeting cards such as sound generating greeting cards and other novelties. The thickness of the speaker is minimized while maintaining the sound quality and increasing strength. The speaker magnet is counter-sunk into the housing of the speaker, thereby decreasing overall thickness. The speaker is configured with concentric ribs that radiate outward from the center of the circular speaker. The ribs reinforce the plastic housing and increase the structural strength of the speaker.

Abstract: A loudspeaker can provide magnetic flux from polarity-aligned split magnets to drive voice coils and generate sound. The loudspeaker may have reduced stray magnetic fields and a BL curve with symmetric and linear characteristics. The loudspeaker can include a core, split magnets, a magnet housing, a core cap, and a voice coil gap formed between the magnet housing and the core cap. Magnetic flux produced by the split magnets may be combined, directed, and/or concentrated by the core cap and magnet housing within the voice coil gap. At least portions of a voice coil may be positioned within the voice coil gap and a diaphragm may be coupled to the voice coil. A bucking magnet assembly may contain a magnetic flux of the magnet structure to further improve performance. The bucking magnet assembly may include split magnets with an aligned polarity that is opposite the polarity of the magnet structure.

Abstract: Disclosed is a free air magnetic circuit and speaker in which no pole piece is used. A magnet layer is located between a top plate and a back plate with a gap defined essentially in the center thereof. Into the gap, a wire coil attached to a diaphragm may be inserted. A magnet flux passes between the top and back plates. In some embodiments, the interior edge of each of the metal plates tapers toward the gap, and the magnet layer extends past the peripheral edge of each of the metal plates so as to discourage magnetic flux between the metal layers at the peripheral edge.

Abstract: A sensory signal output apparatus is provided. The sensory signal output apparatus, includes: a magnetic circuit vibrating in response to an alternating signal flowing through a coil; and an elastic support means elastically supporting the magnetic circuit to surround the circumferential outer surface of the magnetic circuit from one side direction thereof, in which coupling recesses are formed at the circumferential outer surface of the magnetic circuit to be spaced apart from each other, and a coupling piece is provided at a periphery of the elastic support means to be coupled to the coupling recess, the coupling piece is attached to and inserted into the coupling recess. In the sensory signal output apparatus, an elastic support means is inserted into and coupled to a magnetic circuit without using a curling operation to provide easy coupling.

Abstract: An electrodynamic transducer includes a frame and contains at least one electric coil which is placed in a static magnetic field and which can move about a rest position in a vertical free space. The coil(s) is wound around and fixed to a mandrel and a return member is used to return the coil-bearing mandrel to the rest position in the absence of an external bias, the straight cylinder defining an inner volume and an outer volume. The magnetic field is produced by outer and inner magnetic structures which each comprise at least one fixed permanent magnet in the form of a ring. The motor does not contain any ferromagnetic or magnetic part between the outer volume and the inner volume. At least the part of the frame that is used to fix the magnets is made from a non-ferromagnetic and non-magnetic material.

Abstract: A drive cone 11 and a diaphragm 14 are integrally driven by a voice coil 6 movably disposed in a magnetic gap 5. Peripheral edge portions of the drive cone 11 and the diaphragm 14 are supported by a frame 12 via different edge portions 13 and 15, respectively. The drive cone 11 is provided with a rising-up portion 11a which rises up toward an acoustic radiation direction from a inner circumferential end, and a rising-down portion 11b which rises down toward a direction reverse to the acoustic radiation direction. An inner circumferential edge of the diaphragm 14 is fixed at an annular top formed between the rising-up portion and the rising-down portion. Moreover, a first rib 11c and a second rib 11d are formed on the drive cone 11 in such a manner as to rise up toward the acoustic radiation direction integrally with the drive cone. The diaphragm 14 is supported also at the tips of the ribs.

Abstract: A speaker device includes a damper allowing high linearity. The speaker device includes a vibration body including a damper and a voice coil bobbin (bobbin), and a magnetic circuit having a plate. The damper has a first member arranged opposite the plate, and a second member projecting on a side of the plate from the first member. The first member has a movable part elastically supporting the bobbin. The movable part is a flat plate, and behaves with respect to a bent part provided between the movable part and the second member with movement of the bobbin in an acoustic radiation direction and reverse. Therefore, when a constant force is given to the damper via the voice coil, a displacement of the damper with respect to a rest position can be substantially similar in such a case that the damper behaves in the acoustic radiation direction and the reverse.

Abstract: A voice coil 6 is movably disposed in a magnetic gap 5. A drive cone (first diaphragm) 11 and a diaphragm (second diaphragm) 14 are integrally driven by the voice coil 6. Peripheral edge portion of the drive cone 11 and the diaphragm 14 are supported by a frame 12 through edge portions 13 and 15, respectively. An annular adhesive receiver 8 is disposed in a peripheral surface of a voice coil bobbin 7 around which the voice coil 6 is wound, and an inner peripheral edge 11a of the drive cone 11 is accommodated in the adhesive receiver 8. The drive cone 11, the adhesive receiver 8 and the voice coil bobbin 7 are connected to each other by an adhesive filled into the adhesive receiver 8.

Abstract: A speaker includes a frame, a diaphragm, a cover, a magnetic device, and a voice coil. The cover and the diaphragm are both disposed on a first side of the frame, and the cover covers the diaphragm. The magnet device is disposed on a second side of the frame. The voice coil is disposed on the magnetic loop generated by the magnetic device and integrated with the diaphragm. The magnetic device includes a yoke, a magnet, and a pole piece. The yoke includes a protrusion by bending for the magnet and the pole piece to be mounted upon.

Abstract: There is provided a speaker which has a frame structure divided into a first frame and a second frame, wherein tinsel wires are arranged so as not to overlap, with respect to the plane direction, the second frame to which a magnetic circuit is attached, whereby the second frame can be arranged as forward as possible thus enabling reduction of the thickness of the speaker. Also, the first frame and the second frame are both provided with respective frame connection mechanisms and therefore can be easily positioned and connected to each other thus enhancing the workability. The speaker enables further reduction of the thickness without deteriorating input durability and bass range reproduction capability and can be produced with an excellent assembly workability.

Abstract: An earphone speaker including a conductive housing, a micro speaker module, and a circuit board is provided. The conductive housing has a holding space. The micro speaker module is disposed in the holding space. The circuit board is disposed outside the conductive housing, and has a first surface facing towards the conductive housing and a second surface corresponding to the first surface. A positive terminal and a negative terminal are disposed on the second surface and electrically connected to the micro speaker module. A conductive material layer is disposed on the first surface and electrically connected to the negative terminal, and the conductive material layer is directly contacted with the conductive housing.

Abstract: A transducer including a frame and a panel disposed within the frame and coupled to the frame such that the panel may rotate relative to the frame about a rotational axis. The transducer includes an actuator positioned to engage the panel such that the panel rotates about the rotational axis.

Abstract: Contemplated planar magnetic microphones have a magnet and diaphragm arrangement such that substantially homogenous vertical and high horizontal magnetic flux density is realized in the inter-magnet space. Most preferably, the diaphragm is disposed in the inter-magnet space and includes a voice coil covering a significant fraction of the active portion of the membrane. In further especially preferred aspects, the membrane is sufficiently strong and tensioned to allow a large elastic excursion in the inter-magnet space. Consequently, contemplated planar magnetic microphones provide exceptionally large dynamic range without compression and/or distortion and can be easily configured to operate in an environment that is subject to moisture, rain, or to even operate in a submerged environment. Moreover, contemplated microphones can be used as speakers at even high SPL without reconfiguration.

Abstract: A speaker capable of properly adjusting a spring characteristic with which a voice coil is driven and capable of being driven in large amplitude. When a position control coil wound around a bobbin is at a reference position, both ends of the coil cross a magnetic gap formed between external and internal yokes by a predetermined length and Lorentz forces acting on the front and rear ends are balanced. When the voice coil moves in either forward or rearward direction, lengths of the magnetic gap crossed by the front and rear ends of the control coil are different therebetween, and the vector sum of Lorentz forces acting on the position control coil is opposite in direction from the movement of the voice coil, whereby the voice coil is stably held at the reference position.

Abstract: A speaker having a voice coil is disclosed. The voice coil includes two parallel main members and two linking members connecting the two main members for forming a closed loop, one of the linking member having at least a first part from a first circle having a first diameter, and at least a second part from a second circle having a second diameter greater than the first diameter.

Abstract: A speaker includes a yoke defining a receiving cavity therein, a first magnet received in the receiving cavity of the yoke, a second magnet received in the receiving cavity of the yoke and opposite to the first magnet, a first coil surrounding the first magnet, a second coil surrounding the second magnet, and a diaphragm drove to vibrate by both of the first coil and the second coil. A shape of the first coil is approximately a horse's hoof and defines a first linear side, a flexuous side and a pair of first arc sides coupled with two ends of the first linear side and two ends of the flexuous side.

Abstract: The invention provides an electroacoustic transducer capable of efficiently carrying out conversion from electric signals to sound or from sound to electric signals at low distortion, which requires no special shape nor processing as a magnet, requires no minute setting of the magnetization direction, and sets a distribution of higher magnetic flux densities for effective action with respect to an electric conductor of an acoustic diaphragm than in a magnet plate magnetized in the radius direction although the production process thereof is remarkably simple as in a magnet plate magnetized in the radius direction.

Abstract: A speaker apparatus has a container holding a volume of ferrofluid, a permanent magnet suspended in the ferrofluid, and a magnetic excitation apparatus proximate the container. Operation of the excitation apparatus causes movement of the permanent magnet, translated through the ferrofluid to walls of the container, which walls act as resonators creating sound waves in surrounding medium. Audio production is accomplished placing a ferrofluid and a permanent magnet in a container, placing an excitation apparatus in proximity of the permanent magnet, and driving the excitation apparatus to cause movement of the permanent magnet translated through the ferrofluid to walls of the container, which walls act as resonators creating sound waves in surrounding medium.

Abstract: A magnetic structure generating a magnetic field for an ironless motor of an electrodynamic loudspeaker having a mobile coil, wherein the magnetic structure generates a magnetic field in a gap in which the coil is arranged. The magnetic structure includes of a stack of three magnets corresponding to one intermediate magnet and two top and bottom covering magnets, the magnets forming a straight gap border and being located side by side, the intermediate magnet having a radial magnetic polarization, the covering magnets having identical magnetic polarizations and remanent magnetizations. The covering magnets have a radial or axial magnetic polarization. When magnetic polarization of the covering magnets is radial, remanent magnetization of each covering magnet is higher than remanent magnetization of the intermediate magnet, and when magnetic polarization of the covering magnets is axial, remanent magnetization of each covering magnet is lower than remanent magnetization of the intermediate magnet.

Abstract: Provided are a microspeaker and a method of designing the same.

Abstract: A speaker device, wherein vibration of a magnetic circuit section is suppressed with a magnetic influence on the magnetic circuit section suppressed. A speaker device having a vibration section and generating an audio sound by vibration of the vibration section is provided with a magnetic section for forming a magnetic field for vibrating the vibration section and also with a weight section fixed to the magnetic circuit section and suppressing vibration of the magnetic circuit section subjected to reaction force caused by vibration of the vibration section. The weight section is fixed to the magnetic circuit section through a joint section for joining the magnetic circuit section and the weight section to each other, and this forms between the magnetic circuit section and the weight section a predetermined space for magnetically separating the magnetic circuit section and the weight section from each other.

Abstract: A thin and cost-effective bi-directional loudspeaker which can reproduce high quality sound toward contrary directions simultaneously, arranged from bottom to the top, consists of a frame (2), a U-yoke (3), a first magnet (4), a washer (5), a copper cap (6), a second magnet (7), a voice coil (8), a diaphragm (9), a spacer (12), a spider (15), a dust cap (18) and a connector (1) disposed on lateral side of the frame (2). Said loudspeaker is characterized in that: said diaphragm (9) is in a cone shape whose an inner edge (10) of said apex is fixed with top of said voice coil (8). A periphery (16) of the spider (15) is fixed with an upper edge (14) of the supporting ring (12) and a bottom edge (13) thereof is fixed with an exterior (11) of the diaphragm (9). Said spider (15), spacer (12) and diaphragm (9) are coupled by adhesive and fixed on top of said frame (2).

Abstract: A speaker includes a diaphragm 11, edges 12, at least one voice coil bobbin 14, a voice coil 15, and a magnetic circuit 21. The diaphragm 11 is a long flat plate. The edges 12 at ends of the diaphragm 11 in a longer-side direction support the diaphragm 11 to vibrate. The voice coil bobbin 14 has a substantially square pillar shape with a height more than twice as vibrational amplitude of the diaphragm 11, includes an opening having a periphery connected directly to the diaphragm 11, and supports the diaphragm 11 to transmit vibration to it. The voice coil 15 is wound around an outer periphery of the voice coil bobbin 14 substantially at center in a height direction. The magnetic circuit 12 drives the voice coil 15. The long speaker is unlikely to cause breakeup resonance, and has smooth frequency characteristics to offer good sound quality.