When the starting device is opened, the motor enters normal operation. The crankshaft of the compressor is driven by a triangular pulley, and then the piston moves in a reciprocating straight line in the cylinder through a connecting rod and a cross head. When the piston moves from the outer dead point to the inner dead point, the outer side of the inner piston of the cylinder is in a low pressure state. The gas enters the cylinder through the near-term valve. When the piston moves from the inner dead point to the outer dead point, the intake valve closes and the gas in the cylinder is compressed to increase the pressure. When the pressure exceeds the gas outside the exhaust valve When the pressure is applied, the exhaust valve opens and the compressed gas is discharged. When the piston reaches the outer stop point, the exhaust gas is discharged. Complete. After the gas is compressed by the first cylinder and cooled by the intermediate cooler, it enters the second cylinder and is compressed into the gas storage tank for use.