PURPOSE: To obtain a power from a motion of a heavy-weight object by arranging a high pressure gas vessel on and under a heavy-weight object and causing each high- pressure gas vessel to act on a fall motion of a heavy-weight object.

CONSTITUTION: A high-pressure gas vessel 4 is provided on the upper part of a heavy-weight object 6 and a parent piston 18 is installed on the lower part of the heavy-weight object 6. Inside the piston 18, a high-pressure gas chamber 17 and a piston 15 are provided. A fixed piston 14 is set to the said piston 15 and the piston 14 is fixed on the lower part of the parent piston 18 by means of a branch tube. In addition, a piston 11 is mounted on the piston 15. On the upper part of the parent piston 18, a triangular arm 16 which conducts chain belt 32 is provided. The heavy- weight object is lifted upto where a piston for a high-pressure gas vessel contracts and then is released to drop. A piston 8 acts on the piston 11, compressing the high-pressure air chambers 12, 17 and a high-pressure air source tank 19. On account of a repulsive force generated by the mentioned compression, the heavy- weight object again ascends, compressing a high-pressure gas vessel and dropping. This process is repeated maintaining a vertical motion. The vertical motion of the parent piston drives a chain through the intermediary of the triangular arm, resulting in the rotation of a generator.