Abstract: A loudspeaker apparatus in which a diaphragm is reinforced easily and favorably. The loudspeaker apparatus includes a loudspeaker diaphragm formed by joining a domed diaphragm and an edge-like diaphragm and vibrated using a voice coil, and a reinforcement ring reinforcing a junctional flat portion or the vicinity of the junctional flat portion of the diaphragm. The reinforcement ring is formed of a permeable material, and the permeable reinforcement ring is stuck to the junctional flat portion or the vicinity of the junctional flat portion of the diaphragm.

Abstract: A hybrid actuator (100A) includes a magnetostrictive actuator (110) having a magnetostrictive element (111), and a moving-coil actuator (130) including a movable portion (132) having an outer periphery to which voice coils (131a), (131b) are attached. The actuator (110) is fixed to the movable portion (132) of the actuator (130) so that the direction of displacement output of a drive rod (113) becomes the same as the displacement direction of this movable portion. Since the actuator (110) is fixed to the movable portion (132) of the actuator (130), together with a displacement output in response to a high-frequency-range audio signal, which is obtained by the actuator (110), a displacement output in response to a low-frequency-range audio signal, which is obtained by the actuator (130), is also obtained at a tip of the drive rod (113). By abutting the tip of the drive rod (113) against an acoustic diaphragm, a wide band audio output can be obtained.

Abstract: A loudspeaker apparatus includes an acoustic diaphragm; a support member having a housing, which is a hole in a surface of the support member facing the acoustic diaphragm; a magnetostrictive actuator having a magnetostrictor and a drive rod coupled to an end of the magnetostrictor, the magnetostrictive actuator being inserted into the housing such that the drive rod contacts the acoustic diaphragm, the magnetostrictive actuator applying vibration to the acoustic diaphragm; and a spring inserted into the housing from a position opposite to a position of the drive rod of the magnetostrictive actuator, the spring pressing the magnetostrictive actuator toward the acoustic diaphragm and applying a load to the magnetostrictor.

Abstract: A speaker apparatus includes an acoustic vibration plate, and an actuator mounted to the acoustic vibration plate such that one end and the other end thereof, in a driving axis direction, exist in a plate surface of the acoustic vibration plate. The actuator applies vibration to the acoustic vibration plate to play back sound. The speaker apparatus enables a sound image to uniformly spread over the entire plate surface of the acoustic vibration plate. In addition, the entire speaker apparatus can be made compact.

Abstract: A magnetostriction device is made such that an impregnated composition material, such as phenol resin, a resin in which an inorganic material such as silica is dispersed into a phenol resin, an epoxy based resin, or an acrylic resin is impregnated and caked into holes of a magnetostrictive sintered material manufactured by a powder metallurgy method. This magnetostriction device has improved mechanical strength against external force.

Abstract: A magnetostrictive actuator has magnetostrictive element having a magnetostrictive, a driving rod moving in a displacement direction of the magnetostrictive element, which is connected with the magnetostrictive element and made of a ferromagnet, a solenoid coil applying magnetic field to the magnetostrictive element, which is arranged around the magnetostrictive element, an enclosure enclosing the magnetostrictive element and the solenoid coil. In the enclosure, a permanent magnet for applying static magnetic bias field to the magnetostrictive element and tubular cases including a ferromagnet are arranged around the enclosed magnetostrictive element, and the driving rod is arranged in the enclosure with a space. Magnetic pull-in force caused between the driving rod and the enclosure can apply prestress to the magnetostrictive element.

Abstract: An electromechanical transformation device has a magnetostrictive actuator and a driving device that drives the magnetostrictive actuator. The driving device drives the magnetostrictive actuator based on any one of the vibration signal and the audio signal or mixed signal of them.

Abstract: In a lever-arm displacement-increasing device, two lever arms are joined at one end. The other end of one of the lever arms is connected to a fixed portion that supports the rear end of an actuator element, and the other end of the other lever arm is connected to a rigid connecting portion connected to the front end of the actuator element. The displacement force of the actuator element is transmitted to the lever arms through the connecting portion, and is further transmitted to a joint between the lever arms. The joint functions as an output displacing portion. The joint changes the displacing direction of the actuator element to a direction orthogonal thereto, and produces a displacement larger than the displacement of the actuator element.

Abstract: A speaker device includes an acoustic-vibration member, an actuator that is driven on the basis of a sound signal and that includes a displacement-output unit that can obtain the displacement corresponding to the sound signal, and a displacement-output-transfer member configured to connect the displacement-output unit to a point predetermined on a face of the acoustic-vibration member. A displacement output of the actuator is transferred to the predetermined point via the displacement-output-transfer member, and the acoustic-vibration member is excited in a face direction from the predetermined point according to the displacement output.

Abstract: A speaker and a magnetic circuit for a speaker, in which the high quality sound is obtained, are provided using a structure which is thin, light-weight and symmetrical in the vibration direction. In three sheets of layered magnets, the first magnet of the first layer and the third magnet of the third layer are arranged in the magnetic directions which repel each other, and the polarity of second magnet of the second layer is arranged perpendicularly to the polarity of the first and third magnets of the first and third layers at the top and bottom thereof. A voice coil wound near the center of a voice coil bobbin is arranged to oppose the second magnet of the second layer of the magnetic circuit composed of the three layers, and the same vibration systems composed of the diaphragms and edges are connected to both the ends of this voice coil bobbin.

Abstract: A loudspeaker device 1 includes an acoustic diaphragm 5 composed of a domed diaphragm 11, an edge-like diaphragm 13, and a junctional flat portion 12 which joins those domed and edge-like diaphragms, and a joined portion 23 where an end surface of a bobbin 4 of a voice coil or of a conductive 1-turn ring 3 is stuck and fixed to the junctional flat portion 12 or a reinforcement ring 15; and the reinforcement ring 15 is stuck and fixed to the junctional flat portion 12 from above or from under, thereby increasing the mechanical strength of the junctional flat portion 12 of the acoustic diaphragm 5. A loudspeaker device in which unnecessary vibrations are removed and also the quality of acoustic signals is excellent up to high range is provided.

Abstract: A speaker has an acoustic diaphragm, and an actuator that is driven based on a first acoustic signal. The actuator has a transmission portion that is directly or indirectly attached to the acoustic diaphragm and transmits a displacement output of the actuator to the acoustic diaphragm. The speaker also has a sounding body that is driven based on a second acoustic signal that is identical to or different from the first acoustic signal.

Abstract: A loudspeaker device 1 includes an acoustic diaphragm 5 composed of a domed diaphragm 11, an edge-like diaphragm 13, and a junctional flat portion 12 which joins those domed and edge-like diaphragms, and a joined portion 23 where an end surface of a bobbin 4 of a voice coil or of a conductive 1-turn ring 3 is stuck and fixed to the junctional flat portion 12 or a reinforcement ring 15; and the reinforcement ring 15 is stuck and fixed to the junctional flat portion 12 from above or from under, thereby increasing the mechanical strength of the junctional flat portion 12 of the acoustic diaphragm 5. A loudspeaker device in which unnecessary vibrations are removed and also the quality of acoustic signals is excellent up to high range is provided.

Abstract: A speaker contains a pipe member containing opposed ends and a sounding body that is driven on the basis of an acoustic signal which is applied to the sounding body. The sounding body is arranged on the same axis as that of the pipe member. Sound wave radiated from the sounding body radiates from the opposed ends of the pipe member.

Abstract: A magnetostrictive actuator has magnetostrictive element having a magnetostrictive, a driving rod mving in a displacement direction of the magnetostrictive element, which is connected with the magnetostrictive element and made of a ferromagnet, a solenoid coil applying magnetic field to the magnetostrictive element, which is arranged around the magnetostrictive element, an enclosure enclosing the magnetostrictive element and the solenoid coil. In the enclosure, a permanent magnet for applying static magnetic bias field to the magnetostrictive element and tubular cases including a ferromagnet are arranged around the enclosed magnetostrictive element, and the driving rod is arranged in the enclosure with a space. Magnetic pull-in force caused between the driving rod and the enclosure can apply prestress to the magnetostrictive element.

Abstract: A speaker has a pipe member with opposed open ends, and a sounding body that is attached to any one of the opposed open ends of the pipe member on the same axle as that of the pipe member. The sounding body is driven on the basis of an acoustic signal that is applied to the sounding body. Sound wave radiated from the sounding body and passed through an inside of the pipe member vibrates with a pipe wall of the pipe member, thereby to enable sound wave corresponding to the acoustic signal to radiate from a whole of an outside surface of the pipe member to outside.

Abstract: In a lever-arm displacement-increasing device, two lever arms are joined at one end. The other end of one of the lever arms is connected to a fixed portion that supports the rear end of an actuator element, and the other end of the other lever arm is connected to a rigid connecting portion connected to the front end of the actuator element. The displacement force of the actuator element is transmitted to the lever arms through the connecting portion, and is further transmitted to a joint between the lever arms. The joint functions as an output displacing portion. The joint changes the displacing direction of the actuator element to a direction orthogonal thereto, and produces a displacement larger than the displacement of the actuator element.

Abstract: A speaker has an acoustic diaphragm, and an actuator that is driven based on an acoustic signal. The actuator has a transmission portion that is directly or indirectly attached to the acoustic diaphragm and transmits a displacement output of the actuator to the acoustic diaphragm. The actuator vibrates with the acoustic diaphragm by at least its component of the vibration along a plane of the acoustic diagram.

Abstract: A portable audio drive unit has a case, an audio signal output section that outputs an audio signal, and a magnetostrictive actuator that drives on the basis of the audio signal output from the audio output section. The magnetostrictive actuator includes a displacement transfer section. The displacement transfer section has a driving rod. The displacement transfer section transfers a displacement of the driving rod. The magnetostrictive actuator is arranged in the case with the displacement transfer section being protruded from the case or being retractable into the case.

Abstract: An electroacoustic transducer has a cup chamber and a diaphragm made of deformable electrostrictive polymer, which is attached to an opening of the chamber. The electroacoustic transducer also has first and second adaptive electrode layers formed on a front surface and a rear surface of the diaphragm, across which audio signal voltage biased by a direct-current biased voltage is applied. The first and second adaptive electrode layers have shapes that are adjustable according to a change in a shape of the diaphragm. To form the diaphragm, the electrostrictive polymer that has been previously formed to have a concave or convex shape is further formed to have a concave or convex shape, thereby generating a difference in air pressure between the front surface and the rear surface of the previously formed electrostrictive polymer.