Vacuum pump and vacuum apparatus equipped with vacuum pump

摘要

A vacuum pump has an inner cylinder having a hollow portion in fluid communication with atmospheric air, an inner flange disposed on an upper side of the inner cylinder, and an inner sealing groove disposed on an upper end surface of the inner flange. An outer cylinder is disposed over the inner cylinder. The outer cylinder has an outer flange disposed on an upper side of the outer cylinder and an outer sealing groove disposed on an upper end surface of the outer flange. An intake port is disposed at the upper side of the inner and outer cylinders. An exhaust port is disposed at lower sides of the inner and outer cylinders. A pump mechanism pumps gaseous molecules from the intake port to the exhaust port to discharge the gaseous molecules from the exhaust port.