PURPOSE: To enable energy to be continuously taken out without using fuel, etc., by using weights and discs, rotating the discs by making use of gravity, and taking out the torque as power.

CONSTITUTION: Two discs A, B having different diameters are overlapped on the same axis and integrated with each other, and rotatably supported through a spindle fitted in the center C. A groove meandering in the peripheral direction is formed on the outer periphery of the disc B on the small diameter side, and a straight groove extending along the peripheral direction is formed on the outer periphery of the disc A on the large diameter side, and lengths of respective grooves are made equal to each other. A yarn is wound around grooves of respective discs A, B, and the yarn end sides are suspended downward from the peripheral edges of respective discs A, B, and weights D are attached on both ends. The discs A, B are continuously rotated by making use of the action of gravity to be applied to the weights D and the change of the moment by the difference between the diameters of the discs A, B.