Magnetic levitation compound molecular pump

Abstract

The invention relates to a magnetic levitation compound molecular pump which comprises a pump casing, an impeller, spacer rings, stationary blades, a traction-level stator, a permanent magnet high-speed motor, an upper protection bearing, a lower protection bearing, a five-degree-of-freedom magnetic levitation bearing system and a controller. The magnetic levitation compound molecular pump adopts a turbine level and traction level combined design, has a wide pressure range (from 10<-6> Pa to 1 Pa), a high pumping speed, a high compression ratio and a high ultimate vacuum degree, and meets the using requirements of high vacuum and ultrahigh vacuum application industries. meanwhile, the magnetic levitation compound molecular pump adopts a five-degree-of-freedom magnetic levitation bearing, is free of mechanical contact, can achieves a high rotational speed, and has the advantages of no mechanical abrasion, low energy consumption, low noise, long service life, no need for lubrication, no oil stain and the like.

Description

technical field [0001] The invention relates to a molecular pump, in particular to a magnetic suspension composite molecular pump. Background technique [0002] Molecular pump is a mechanical turbine type vacuum obtaining equipment designed according to the law of molecular motion, which can obtain ultra-high vacuum. It is a necessary equipment for accelerators, electron colliders, lasers and other systems, and has a wide range of applications. The pumping mechanism is that in the molecular flow area, the surface of the rigid body moving at high speed transfers momentum to the gas molecules, so that the gas molecules generate directional flow in the direction of motion of the surface of the rigid body, so as to achieve the purpose of pumping. From the pumping principle of the molecular pump, it is known that the rotor blades of the molecular pump must have a linear velocity close to the speed of the gas molecules. Only with such a high speed can the gas molecules collide wit...

AI Technical Summary

Problems solved by technology

[0004] The existing molecular pumps all use traditional mechanical bearings. During the operation of traditional mechanical bearings, there is mechanical wear between the rotor and the stator. The higher the speed, the more serious the wear, and the service life of the bearings will be greatly reduced. Therefore, the molecular The pump is difficult to achieve high speed and the bearings need to be replaced regularly

At the same time, the mechanical bearings in the molecular pump need to be lubricated with oil or grease, and the backflow of oil vapor will pollute the vacuum chamber and affect the product quality

In addition, there is clearance in the mechanical bearing, and the rotor of the molecular pump swings a lot during operation, so the molecular pump has relatively large vibration and noise, short average trouble-free working period, and the installation angle can only be vertical or horizontal.

Images