The vacuum pump which uses direct current to provide electric energy is called direct current oil-free vacuum pump. DC vacuum pump has 5V, 12V, 24V power supply. The volume of 5V, 12V vacuum pump or 24V DC vacuum pump is very small, so it is called micro vacuum pump. The advantage of DC power supply is to avoid motor drive, so as to reduce the power consumption. The power consumption is weak to MA (MA). The system in the pump is integrated, and the weak current automatic control system is adopted, so that the vacuum pump is completely free of manual control, achieving more accurate and intelligent effect. The micro DC vacuum pump mainly uses the circular motion of the motor to make the diaphragm inside the pump do reciprocating motion through the mechanical device, so as to compress and stretch the air in the pump cavity with a fixed volume to form a vacuum (negative pressure), which produces a pressure difference between the pump suction port and the external atmospheric pressure. Under the effect of the pressure difference, the gas is pressed (sucked) into the pump cavity, and then discharged from the exhaust port. Micro vacuum pump has high requirements for air tightness, generally in 10 ^ - 7pam ^ 3 / S (10 minus 7 cubic meters per second) can meet customer requirements for air tightness applications: such as laboratory rare gas analysis, circulation, inspection, etc. The miniature vacuum pump adopts brushless motor to adapt to alternating load, and its service life can be up to thousands of hours (full load, 24-hour continuous test). If it is used intermittently, its service life can be up to 5000-8000 hours.