Abstract: A loudspeaker includes a diaphragm body having a dome shape protruding upwardly, a magnetic circuit disposed below the diaphragm body, a voice coil coupled to the diaphragm body, an edge coupled to an outer circumference of the diaphragm body, and a frame coupled to the edge. The edge includes a first coupling portion provided at an outer circumference of the edge, a second coupling portion provided at an inner circumference of the edge and coupled to an outer circumference of the diaphragm body, and a roll portion disposed between the first coupling portion and the second coupling portion. The edge has a surface facing downward. The frame has a connecting surface disposed below the second coupling portion and coupled to the surface of the edge at the first coupling portion of the edge. This loudspeaker can decrease distortion of sound.

Abstract: A loudspeaker diaphragm includes a base layer and a coating layer. The base layer contains natural fibers. The coating layer is composed of bamboo cellulose nanofibers and is formed at least on the first side of the base layer. The coating layer has a thickness in the range of 3% to 15%, both inclusive of the sum of the thicknesses of the base layer and the coating layer.

Abstract: A loudspeaker includes a diaphragm, a voice coil body, and a magnetic circuit. The diaphragm has a first side, which is the surface of a recess defined by a thin part and a thick part formed around the thin part. The voice coil body includes a bobbin and a voice coil. The bobbin has a first end connected to the thin part on the first side of the diaphragm and a second end opposite to the first end. The magnetic circuit has an inner part, an outer part, and a magnetic gap. Part of the magnetic circuit including the first side of the inner part is located from the second end of the bobbin into the bobbin, and the first side of the inner part and the first side of the outer part are located in the recess so that the voice coil is located in the magnetic gap.

Abstract: The loudspeaker magnetic circuit is an external-magnet type, and has a magnet, an upper plate, and a lower plate. The magnet is sandwiched between the upper plate and the lower plate. At least one of the lower plate and the upper plate is formed of magnetic powder or a mixture of a magnetic powder and resin.

Abstract: A loudspeaker includes a diaphragm, a magnetic circuit, and a frame. The frame includes an outer peripheral part supporting the diaphragm, a center part supporting the magnetic circuit, and a connection part connecting the center part to the outer peripheral part. The outer peripheral part molded with resin includes an inner wall, an outer wall facing the inner wall, and a reinforcing rib provided between the inner wall and the outer wall.

Abstract: The loudspeaker magnetic circuit is an external-magnet type, and has a magnet, an upper plate, and a lower plate. The magnet is sandwiched between the upper plate and the lower plate. At least one of the lower plate and the upper plate is formed of magnetic powder or a mixture of a magnetic powder and resin.

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 loudspeaker includes a diaphragm, a magnetic circuit, and a frame. The frame includes an outer peripheral part supporting the diaphragm, a center part supporting the magnetic circuit, and a connection part connecting the center part to the outer peripheral part. The outer peripheral part molded with resin includes an inner wall, an outer wall facing the inner wall, and a reinforcing rib provided between the inner wall and the outer wall.

Abstract: A magnetic circuit for a loudspeaker includes a magnet and a top plate. The magnet is made of a bonded magnet. The magnet and the top plate are configured to satisfy at least one of conditions that an inner diameter of the magnet is identical to an inner diameter of the top plate, and that an outer diameter of the magnet is identical to an outer diameter of the top plate. This configuration eliminates a wasted space inside the magnetic circuit, and protrusion of the magnet to outside, hence providing a light and efficient magnetic circuit.

Abstract: In a loud speaker, the diaphragm has a protruded part protruding on a yoke side on the inside and in the vicinity of an inner coupling part as a coupled portion to a voice coil. The loud speaker can be manufactured with the voice coil accurately positioned with respect to a diaphragm, and the voice coil is accurately vibrated vertically inside a magnetic gap. The possibility of the voice coil coming into contact with a plate and a yoke as a magnetic circuit body of the loud speaker can be reduced, thereby to improve production efficiency and a yield at the time of manufacturing the loud speaker.

Abstract: A vibration device includes a support system member that supports a diaphragm to allow vibration, a tubular voice coil bobbin attached to the diaphragm, and a magnet disposed on at least one of inner and outer circumferential surface sides of the bobbin. The magnet is polarized in a vibration direction of the diaphragm, and forms a magnetic gap on a side that faces the bobbin. A voice coil is attached to the bobbin and disposed within the magnetic gap, and vibrates the diaphragm and the bobbin in response to a driving force generated when an electrical signal is inputted into the voice coil. A magnetic material member is attached to the bobbin, disposed in a balancing position within the magnetic gap, and, when vibrating with the bobbin, subjected to a magnetic attractive force in a direction away from the balancing position.

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 speaker includes a magnetic circuit, frame, diaphragm, voice coil, and terminals. The frame has an opening and is coupled to the magnetic circuit, and includes a resin portion. The diaphragm is coupled to a rim of the opening of the frame. The voice coil includes lead wires and is coupled to the diaphragm, and a part of the voice coil is disposed at a magnetic gap of the magnetic circuit. The terminals are coupled to the frame by insert-molding. An outer shape formed of the frame and the terminals is one of a rectangle or a square. The resin portion of the frame has cut-away sections at corners of its outer shape. The terminals include protruding sections protruding from the cut-away sections, and the lead wires of the voice coil are connected to the protruding sections.

Abstract: The loudspeaker device according to the present invention comprises a loudspeaker; a feedforward processing section for performing feedforward processing on an electric signal to be inputted to the loudspeaker based on a preset filter coefficient so that non-linear distortion which occurs from the loudspeaker is removed; and a feedback processing section for detecting vibration of the loudspeaker, and performing feedback processing on an electric signal concerning the vibration with respect to the electric signal to be inputted to the loudspeaker. The feedback processing section performs feedback processing on the electric signal concerning the vibration so that the non-linear distortion which occurs from the loudspeaker is removed and so that a frequency characteristic concerning the vibration of the loudspeaker becomes a predetermined frequency characteristic.

Abstract: A loudspeaker system comprises a cabinet, a speaker unit, a package body, a filler gas, and an absorbent. The speaker unit is mounted in the cabinet. At least one package body is disposed in a vacant space inside of the cabinet and is structured by a bag body for sealing materials thereinto from outside thereof. A predetermined amount of the filler gas is sealed into the package body. A predetermined amount of the absorbent is sealed into the package body and physically absorbs the filler gas.

Abstract: In a loud speaker, the diaphragm has a protruded part protruding on a yoke side on the inside and in the vicinity of an inner coupling part as a coupled portion to a voice coil. The loud speaker can be manufactured with the voice coil accurately positioned with respect to a diaphragm, and the voice coil is accurately vibrated vertically inside a magnetic gap. The possibility of the voice coil coming into contact with a plate and a yoke as a magnetic circuit body of the loud speaker can be reduced, thereby to improve production efficiency and a yield at the time of manufacturing the loud speaker.

Abstract: A speaker device includes a cabinet, a speaker unit, a port, a cartridge, and an adsorbent material. The adsorbent material is disposed in the interior of the cartridge. The cartridge is a container removable from the cabinet. When the adsorbent material is deteriorated, the cartridge is replaced or the adsorbent material is reactivated, thereby making it possible to maintain, over a long period of time, the effect of physical adsorption provided by the adsorbent material.

Abstract: A vibration device according to the present invention includes: a diaphragm; a support system member that supports the diaphragm in a manner that allows the diaphragm to vibrate; a tubular voice coil bobbin attached to the diaphragm; a magnet which is disposed on at least one side among an inner circumferential surface side and an outer circumferential surface side of the voice coil bobbin, and which is polarized in a vibration direction of the diaphragm, and which forms a magnetic gap on a side that faces the voice coil bobbin; a voice coil which is attached to the voice coil bobbin so as to be disposed within the magnetic gap, and which vibrates the diaphragm and the voice coil bobbin in response to a driving force generated when an input electrical signal is inputted into the voice coil; and a magnetic material member which is attached to the voice coil bobbin so as to be disposed in a balancing position within the magnetic gap, and which is, when vibrating together with the voice coil bobbin, subjected to

Abstract: A loudspeaker includes a diaphragm, a voice coil fixed to the diaphragm, a first magnet having a first pole surface facing an inner side of the voice coil, a second magnet located inside the inner side of the voice coil, and a first magnetic fluid provided between the first pole surface of the first magnet and the voice coil. The first magnet has the first pole surface facing the inner side of the voice coil. The second magnet has a second pole surface located inside the inner side of the voice coil such that a magnetic flux passing through the first pole surface of the first magnet crosses the voice coil in a direction perpendicular to the voice coil and a vibration direction. The first magnetic fluid contacts the first pole surface and the voice coil. The loudspeaker has a small thickness but can produce a high audio output, while preventing rolling.

Abstract: In a loudspeaker, three magnets are disposed with magnetic gaps formed between them for placing therein a voice coil. The magnets disposed at two sides are so magnetized that the confronting poles have the same polarity. The magnet in the center has its magnetic poles in a direction perpendicular to a direction connecting the poles of the magnets at two sides. A diaphragm has an aperture formed in a position confronting the center magnet. Also provided is a magnetic fluid kept mediating between the sides of the center magnet facing the magnetic gaps and the voice coil.