Vacuum chamber has isolating cylinder with at least one recess engaged by outwardly pressed burls on screen to hold screen in place

摘要

The vacuum chamber has an isolating cylinder (10), a screen (12) and an end cover enclosing a contact point and other components. The isolating cylinder has at least one recess (11) in which outwardly pressed burls (15) on the screen engage and so hold screen in place. Three recesses and three burls can be used.