Abstract: The present invention provides a small electroacoustic transducer which is improved in sound characteristic by enlarging and adjusting a volume of a resonance space. A second resonant chamber as an auxiliary space is formed relative to a first resonant chamber formed in front of a resonance plate, wherein the first and second resonant chambers are connected with each other to enlarge the volume of the resonant volume.

Abstract: The invention provides a miniaturized and low-profile electroacoustic transducer. In the electroacoustic transducer, a space is formed underneath a magnet by diminishing a vertical thickness of the magnet in comparison with the height of a magnetic core, and also by disposing the magnet at a position trensversely aligned to an upper portion of the magnetic core, so that the space is utilized as a part of a back space at the back of a diaphragm, and for connection of terminals of a coil with external terminals, thereby realizing miniaturization and flattening in the shape of the electroacoustic transducer.

Abstract: A terminal connection method of a coil comprises the steps of arranging coil terminals of a coil on lead terminals; removing insulating coats of the coil terminals to expose core wires; and applying an electric conductivity adhesive to connected portions of the coil terminals and the lead terminals. A terminal connection structure of a coil comprises coil terminals arranged on lead terminals, with insulating coats removed from the coil terminals; and an electric conductivity adhesive applied to connected portions of the coil terminals and the lead terminals.

Abstract: An electroacoustic transducer, which has a lead frame previously formed into a predetermined shape, an outer case formed integrally with the lead frame and a drive section including a coil arranged inside the outer case, comprises an opening formed in the outer case; lands formed by exposing a part of the lead frame through an outer surface of the outer case; and the coil having coil terminals led out of the outer case through the opening and connected to the lands.

Abstract: The expansion valve has an operating pressure setting member that can adjust the operating pressure of a pressure-activated diaphragm by moving a spring retainer of an operating spring against the force the spring which is interposed between the diaphragm and the spring retainer. The operating pressure setting member, after being set at a desired setting position, is securely fitted into and crimped by a secondary coolant flow pipe. The operating pressure setting member has a coolant passage for the coolant to pass through. This construction can completely prevent leakage of the coolant from the operating pressure setting member as would occur with conventional expansion valves whose operating pressure setting member is not installed inside the secondary coolant flow pipe.