Importance

Loading Importance Indicators...

Abstract

A method in which a pressure in an imaginary vacuum container is determined by calculation based on a gas flow rate difference between an estimated discharge gas amount determined from the actual opening degree of a vacuum valve provided on the discharge conduit of a vacuum container and an estimated inflow gas amount determined in the preceding operation period, an estimated inflow gas amount at the present time is determined based on a difference between the calculated pressure and a pressure measured in an actual vacuum container by a pressure meter, a set discharge gas amount is determined by adding, to the estimated inflow gas amount, a correction gas amount obtained based on a pressure deviation between a set pressure and the measured pressure, and the degree of opening of the vacuum valve is controlled such that a discharge gas amount reaches the set discharge gas amount.

Loading the Abstract Image...

First Claim