Molecular Pump Structure And Schematic Diagram

The core components of molecular pumps are rotating blades and fixed blades. The speed of rotating blade reaches 1800 ~ 90000rpm, and the speed of blade end reaches hundreds of m/s, which is close to the average speed of molecules. The gas molecules are transported to the exhaust port through the collision with gas molecules. When rotating the rotating blade toward the set at high speed, the probability of the gas molecules moving from the suction side to the exhaust side is A, and the probability of the gas molecules moving from the exhaust side to the suction side is B. When the rotating blade hits the gas molecules, the gas molecules touch the fixed blade and then fly to the next rotating blade again, which is eventually bounced to the exhaust port, making A>B realize the exhaust function.
molecular-pump-structure-and-schematic-diagram

If the blade Angle is large, the exhaust speed is large and the compression ratio is small. When the blade Angle is small, the exhaust velocity is small and the compression ratio is large. The exhaust speed of the molecular pump is basically unaffected by the type of gas. The ultimate pressure of the pump can reach 10-8 Pa, but for light molecules/atoms, the exhaust speed will be reduced.FB_Grease_Lubricated_Hybrid_Molecular_Pump