| 摘要 |
PURPOSE:To generate ultrasonic waves in a metal cylinder body efficiently, by winding a flat coil, which is formed in a vortex shape by using a conductor wire, along the outer surface of a tube shaped or rod shaped metal cylinder body, and connecting a means, which makes a current flow through the coil instantaneously, to the body. CONSTITUTION:A capacitor 4 is charged by a power source 4 and a rectifier 6. When a switch 3 is closed, a discharge current instantaneously flows from the charged capacitor 4, and a magnetic field is generated in the direction of the diameter of a metal cylinder body 2, around which a coil 1 is wound. In the case the material of the metal cylinder body 2 is ferromagnetic material such as iron, the outer part of the metal cylinder body 2 is magnetized by the magnetic field. An attracting force acts between said part and the magnetic force caused by the coil 1. Thus the metal cylinder body 2 is deformed in the direction of the radius. Along with said deformation the metal cylinder body 2 is deformed also in the direction of the length, and pulse shaped ultrasonic waves are generated in the metal cylinder body 2. |
