EXCITER

PROBLEM TO BE SOLVED: To excite an object with high-frequency and also to generate a large centrifugal force by constructing a rotor and a case for receiving the rotor so that a magnetic force balanced with the centrifugal force is exerted on the rotor, in an exciter in which a rotor having a deviated center of gravity from the center of rotation is rotated. SOLUTION: In this exciter 11 which is used as a testing equipment for testing vibration-resistant characteristics of an equipment or structure, a wave generator for analyzing the internal structure of a baserock by exciting the baserock and using the reflected wave, etc., a rotor 13 is supported by a case 12 consisting of a magnetic material so that the axial line of the rotor 13 is directed in the vertical direction and the rotor 13 is freely rotatable. Also, one side of the rotor in a radial direction is provided with a weight 15 and the other side in the radial direction is provided with a permanent magnet 16 and the rotor 13 is rotated to exert a centrifugal force on the side of the weight 15. By balancing this centrifugal force and the magnetic force of the permanent magnet 16, that is exerted on the inner peripheral surface of the case 12 with each other, the case 12 is vibrated in such a way that it is rotated together with the rotor 13 to transmit this vibration to an object to be excited 19 in contact with the case 12.