PURPOSE: To permit perpetual rotation by separating two weights from each other on a stem to expand and contract a rod at the maximum by centrifugal force and regulation of the outer periphery and permit natural rotation by utilizing gravity, levers and centrifugal force.

CONSTITUTION: The center of rotational movement is placed eccentrically to a circle for regulating the movement. Two weights AA', BB'WDD' are respectively separated from each other through rods 3 about a rotary shaft 2. When the respective weights are moved by centrifugal force and regulation of the outer circumference, the rods are adapted to expand and contrac. Thus, the weights AWD side always tends to drop and the weights A'WD' are lifted because of inferior moment. Hence the respective weights are moved sequentially by the action of gravity, lever and centrifugal force so that perpetual motion without stop can be obtained from the rotary shaft 2.