Observation window cleaning in process chamber contg. fine particles - inert gas is fed into chamber behind lens through porous inner pipe and leaves via opening into main process chamber

摘要

Observation window for a process chamber has a facility for maintaining the clarity of the sight glass. An unidirectional stream of a cleaning gas passes the glass lens and directly into the process chamber. Gas enters the cleaning chamber behind the lens from a ring shaped passage around the circumference of the window body. A porous wall between the passage and the inner cleaning chamber allows the gas in and distributes it over the inner face of the window before it leaves through an opening into the main processing chamber. USE/ADVANTAGE - For observation of prodn. of by-prods., in partic. fine or vaporised pwoders, during powder prodn. by a melt processing. Window lens is maintained clear of finely distributed particles allowing clear observation of the process at all times.