After the driving machine is started, it drives the compressor crankshaft to rotate through the triangular belt, which is transformed into a piston through the crank rod mechanism to make reciprocating motion in the cylinder. When the piston moves from the cover to the shaft, the cylinder volume increases, the pressure in the cylinder is lower than the atmospheric pressure, and the external air enters the cylinder through the filter and suction valve; After reaching the bottom dead center, the piston moves from the shaft side to the cover side, the suction valve is closed, the cylinder volume gradually decreases, the air in the cylinder is compressed and the pressure increases. When the pressure reaches a certain value, the exhaust valve is pushed open, and the compressed air enters the air storage tank through the pipeline. In this way, the compressor works round and round, continuously transmits compressed air to the air storage tank, and gradually increases the pressure in the tank, So as to obtain the required compressed air.