The structure and working principle of single and double stage rotary vane vacuum pump _

single-stage rotary vane vacuum pump is only one studio. This pump is mainly composed of the stator, and rotor. The rotor is mounted eccentrically in the pump cavity, double rotating plate, are installed in the rotor slot due to spring force, rotor slot near the cylinder wall, The same is true of the centrifugal force after rotating rotary-vane) 。 The rotor and rotor stator cavity divided into two parts: suction and discharge.

when the rotor in the stator rotating cavity, the volume of air intake gradually expand, in gas, 'a' side of the exhaust volume decreases, with compressed gas suction, and is discharged from the exhaust valve.

in the exhaust valve in the oil, to prevent the air into the pump. Vacuum water pump oil through the oil hole and exhaust valve into the pump chamber, the pump cavity of all sports surface covered with oil, and form a seal between the suction chamber and exhaust cavity.

in order to improve the vacuum of vacuum pump, in addition to improve the pump body, rotor and rotor machining accuracy, minimize assembly clearance and harmful space, the most effective way is to double single stage pump series into a double pump.

the water pump is composed of double a studio. In series with the double a chamber in the same direction with the same speed. A room is room B level, before A room is low vacuum level, room B is high vacuum level. Inhalation of gases by high vacuum level ( Room B) The top level, and through the exhaust valve from the eduction in pump. Top level ( A) And single stage pump type, the oil into the pump chamber, at any time and high vacuum level ( B) Only a small amount of oil at the start of work, the work after a period, there is no oil enters the pump chamber. When the pump start things, and in gas pressure is higher, For example, from the beginning of the atmospheric pressure extraction) , gas room B contraction, pressure increase, the part of the compressed gas directly from the auxiliary exhaust valve ( 1) Discharge, others via level before discharge.

when the vacuum pump work after period of time, room B inhalation of gas pressure is low, although the room B contraction, pressure is not a above atmospheric pressure, not open for exhaust valve ( 1) The inhaled air all level before entering A room, the room A continue to compress, the exhaust valve ( 3) Eduction.

vacuum pump work after a period of time, due to the high vacuum stage inlet pressure is reduced greatly, the double pump outlet pressure is small, so the pressure difference at the inlet and outlet of the B room also is very small, the number of compressed gas flow is reduced; Level at the same time, the former room A will continuously after the evaporation of oil pump molecules, reduces the partial pressure of oil vapor, make double pump oil is smaller than single pump, ultimate vacuum would improve greatly. Countries before the limit of double rotary vane vacuum pump pressure can be 10 - 2 pa, WaiYang some pump can reach 10 - 3Pa。