| 摘要 |
PROBLEM TO BE SOLVED: To provide a vibration source by which a clear waveform can be generated with satisfactory efficiency by a method wherein a wide frequency band can e be covered, a dipole vibration-source operation and a monopole vibration-source operation can be performed, and a structure is formed to be simple and easy to maintain. SOLUTION: Two rectangular diaphragms 24 composed of an electric conductor are faced and arranged in a magnetic filed with some interval. Currents in the same direction or opposite directions are made to flow to the diaphragms. The dipole vibration-source operation or the monopole vibration-source operation is performed. The diaphragms are installed so as to face both windows 22 at the inside of a cylindrical case 20 in which the windows are opened in opposite side faces, and both ends are fixed. Permanent magnets 26 are arranged and installed on both sides of the diaphragms in such a way that the direction of a magnetic flux is generated in the widthwise direction of the diaphragms. The diaphragms have a structure in which the surface and the rear of, e.g. a ribbonlike metal aluminum foil are covered with a flexible resin. |
