Abstract: A method of ultrasonic welding for a resin case in which an ultrasonic vibration is applied to the resin case in a direction parallel to the welding surface.

Abstract: A lead terminal connection structure of an electroacoustic transducer comprises a lead terminal member having a pair of lead terminals integrated via a bridge piece. The lead terminals have solder surfaces to be soldered to the surface of a circuit board of another device on which an electroacoustic transducer is to be installed. When the lead terminal member is attached to a circuit board of the electroacoustic transducer and the bridge piece is cut, the pair of lead terminals become separate from each other.

Abstract: The present invention provides a fabrication method of an electroacoustic transducer capable of simplifying an assembling process on a lead frame and realizing an automatic assembly. The method comprises steps of forming pole piece portions, forming a lead frame having a plurality of base forming areas thereon, each of the areas having lead terminals formed therein, forming bases of a synthetic resin on the lead frame by molding so that the pole piece portions are embedded in the bases, mounting a coil on the pole piece portions embedded in the bases, disposing a support ring and a magnet so as to surround the coil, and placing a diaphragm on the support ring to be held thereby, connecting opposite ends of the coil to the lead terminals, cutting off the lead terminals from the lead frame, putting cases on and fixedly joining the same to the bases, and subjecting the cut lead terminals to a forming process.

Abstract: The present invention provides an electroacoustic transducer and a method of fabricating the same, employing a lead frame to integrally form a plurality of component parts, thus reducing the number of individual component parts, and improving assembly efficiency. The electroacoustic transducer comprises a base, a yoke fixed to the base, a core, a coil wound around the core, magnet surrounding the coil, a support ring surrounding the magnet, a vibrating plate supported on the support ring, lead terminals fixed to the base, and a case having a sound emitting cylinder and joined to the base so as to cover those components. A gap is formed between the core and the diaphragm. The diaphragm, the gap, the core, the yoke and the magnet form a closed magnetic path. The coil drives the diaphragm for vibration when energized. The yoke and the lead terminals are integrally formed of a common metal material such as the lead frame. The core may be integrally formed with the yoke of the lead frame.

Abstract: In an electroacoustic transducer, the opening portion of a casing body which contains therein a magnetic driving portion for converting an electric signal into a sound is closed by a casing cap to form a resonance space (resonance chamber) which resonates in response to an acoustic vibration generated by the magnetic driving portion, wherein a plurality of slender projections to be entered into said casing body are projected from the casing cap to position said casing cap relative to said casing body. As a result, it is possible to enlarge the capacity of the resonance chamber and improve the assembling accuracy.

Abstract: An electroacoustic transducer having a diaphragm and a magnetic driving portion respectively housed in a housing wherein the magnetic driving portion vibrates the diaphragm magnetically in response to an electric signal. A base member for closing an opening at the rear side of the housing is formed of a metallic plate. Lead portions are provided by extending both ends of a coil of the magnetic driving portion. Terminal patterns are formed on a surface of the base member with an insulating film between them. The lead portions of the coil of the magnetic drive portion are connected to the terminal patterns.

Abstract: A small and thin buzzer which can be mounted on a printed circuit board. A buzzer assembly and a lead connecting chamber are provided in a buzzer case. One end of each of the terminals for external connection is extended to the inside of the lead connecting chamber and the exciting coil terminals of the buzzer assembly are connected to the terminals for external connection within the buzzer case. A lead groove for leading the exciting coil terminals therethrough are provided on the inner surface of the buzzer case. Thus, the connection between the exciting coil terminals and the terminals for external connection is facilitated and a resonance space for the buzzer assembly is secured.