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

Abstract: An electro-acoustic transducer has a layer of a heat-curing and UV-curing adhesive formed on a frame integrally molded at the bottom of a case. A magnet is placed on the frame via the adhesive. The case is irradiated with a UV light from above, at least before the adhesive is heat-cured, so that the adhesive is cured in the portion exposed to the UV light. This prevents the adhesive from evaporating, scattering and prevents the adhesive components depositing on a diaphragm, that could be caused by a later high temperature process for heat-curing the adhesive. Furthermore, time for the heat-curing can be made shorter by the high temperature curing. The shorter curing time improves productivity of the production, and allows the transducers to be manufactured on an automatic assembly line.

Abstract: The present invention relates to a member for electric equipment, having a surface treatment layer mainly consisting of colloidal silica formed on a surface of a metallic component with a zinc or zinc alloy layer formed thereon, and a protective layer formed on a surface of the surface treatment layer. Further, the surface treatment layer includes at least one of aluminum, titanium, and cobalt as a metallic component. According to a configuration of the present invention, it is possible to provide a metallic member for the electric equipment and a member for an electro-acoustic transducer that has excellent heat resistance, corrosion resistance, and bonding strength.

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

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