EXHAUST PRESSURE CONTROL SYSTEM AND METHOD FOR CONTROLLING THE VALVE OPENING DEGREE OF A VACUUM VALVE ARRANGED IN AN EXHAUST SYSTEM

摘要

PURPOSE: An exhaust pressure control system and method are provided to increase the maintenance cycle of a vacuum valve by reducing the number of maintenance where the vacuum valve is disassembled to remove by-products.;CONSTITUTION: An exhaust pressure control system comprises a vacuum valve, a controller(12), a purge gas supply system, and a purge gas flow rate controller(13). The vacuum valve is installed in an exhaust system connected to a vacuum chamber. The controller controls the opening degree of the vacuum valve in order to control the exhaust pressure of the exhaust system to the target pressure. The purge gas supply system is connected to the exhaust system. The purge gas flow rate controller is provided in the purge gas supply system and controls the flow rate of purge gas provided to the exhaust system. The purge gas with the flow rate controlled with the purge gas flow rate controller is supplied to the exhaust system so that the opening degree of the vacuum valve controlled by the controller is greater than the opening degree when controlling the exhaust pressure to the target pressure without supplying the purge gas to the exhaust system.;COPYRIGHT KIPO 2011