Patent ID: 8316879
Filing Date: 2012-11-27
Classification: G05D,Y10T

Abstract:
1. A pressure controller for controlling a pressure in a vacuum container in a vacuum processing device comprising: the vacuum container to which a gas supply conduit and a discharge conduit are connected; a vacuum valve provided on the discharge conduit so as to open and close the discharge conduit; a pressure meter for measuring the pressure in the vacuum container; and an opening degree detector for detecting a degree of opening of the vacuum valve, the pressure controller comprising: a pressure setting section for setting a target pressure of the vacuum container; an inflow gas amount estimating section that determines a calculated pressure in an imaginary vacuum container using a calculation model and based on a gas amount obtained in consideration of an estimated discharge gas amount determined according to the degree of opening detected by the opening degree detector, and determines an estimated inflow gas amount based on a pressure difference between the calculated pressure in the imaginary vacuum container and a pressure measured in an actual vacuum container by the pressure meter; a gas amount correcting section having a pressure subtracting section that receives the set pressure from the pressure setting section and the measured pressure from the pressure meter to determine a pressure deviation, and a proportional control section that receives the pressure deviation determined in the pressure subtracting section and multiplies the pressure deviation by a predetermined gain to obtain a correction gas amount; an adding section that adds the estimated inflow gas amount determined in the inflow gas amount estimating section and the correction gas amount determined in the gas amount correcting section to determine a set discharge gas amount; and a valve opening degree calculating section that receives the set discharge gas amount obtained in the adding section and the set pressure from the pressure setting section to determine a valve opening degree, wherein in the inflow gas amount estimating section, the calculated pressure in the imaginary vacuum container is determined using the calculation model and is based on the gas amount, and an operation for determining the estimated inflow gas amount is performed in each predetermined period based on the pressure difference between the calculated pressure in the imaginary vacuum container and the pressure measured in the actual vacuum container by the pressure meter, and in the inflow gas amount estimating section, the gas amount used for determining the calculated pressure in the imaginary vacuum container is a gas flow rate difference obtained by subtracting the estimated discharge gas amount from the estimated inflow gas amount.