Vacuum evacuation device

Abstract

A vacuum evacuation device including: a main pump; an auxiliary pump connected in series to the main pump; and an inter-pump piping for interconnecting an outlet of the main pump and an inlet of the auxiliary pump, wherein the main pump includes a mechanical booster pump; a ratio of the maximum power of a motor for the main pump to the maximum pumping rate of the main pump is no less than 5 W/(m 3 /h); the inter-pump piping includes a branch pipe branched from the middle of the inter-pump piping; and a check valve for releasing gas in the inter-pump piping and preventing a back flow of the gas is provided in the middle of the branch pipe.

1 . A vacuum evacuation device comprising:
 a main pump;   an auxiliary pump connected in series to the main pump; and   an inter-pump piping for interconnecting an outlet of the main pump and an inlet of the auxiliary pump, wherein the main pump comprises a mechanical booster pump;   a ratio of the maximum power of a motor for the main pump to the maximum pumping rate of the main pump is no less than 5 W/(m 3 /h);   the inter-pump piping comprises a branch pipe branched from the middle of the inter-pump piping; and   a check valve for releasing gas in the inter-pump piping and preventing a back flow of the gas is provided in the middle of the branch pipe.   
     
     
         2 . The vacuum evacuation device according to  claim 1 , wherein the main pump comprises a plurality of the mechanical booster pumps which are arranged in parallel. 
     
     
         3 . The vacuum evacuation device according to  claim 1 , wherein the branch pipe is terminated with an exhaust pipe of the auxiliary pump. 
     
     
         4 . The vacuum evacuation device according to  claim 1 , wherein a pressure loss of a gas flow in the check valve is no more than 10,000 Pa when operating the main pump at atmospheric pressure.