To provide a method for generating compressed air capable of generating compressed air while saving energy sources without using such energy as electric power and liquid fuel.
A cylinder 4 is disposed in an aquarium 1 immediately above an air inlet 3 so as to be vertically moved, and an extensible piston 5 which is extensible vertically and the lower part of which is affixed watertight to the inner peripheral surface of the cylinder 4 is extended to open a check valve 7 so as to intake outside air to the extensible piston 5 form the air inlet 3 by only an amount increased with a capacity of the check valve. In a state that the check valve 7 of the air inlet 3 is closed, the cylinder 4 is raised and the extensible piston 5 is retracted to release the air of an amount corresponding to the retraction of the extensible piston 5 from the bottom end of the cylinder 4 into water, and air pressurized by hydraulic pressure is captured and collected.
Higashio Masahiro
Takayoshi Tagawa