PROBLEM TO BE SOLVED: To reduce the size by enhancing energy efficiency by converting energy consumed for rotation of an eccentric weight into vibration, rotation and rocking force. SOLUTION: This exciter is installed by shifting a phase of the eccentric weight by 180 degrees, and generates the rotation and the rocking force by couple of force by motion of the eccentric weight together with vertical directional vibration by the rotation of the eccentric weight by making a plane of rotation different, and efficiently takes out input energy as vibration. This exciter can be miniaturized since the energy efficiency is superior, and can be applied to a small excavator and a small soil sampler. COPYRIGHT: (C)2004,JPO&NCIPI