Frame member for pressurized screening device

摘要

The frame member for pressurized screening device includes an inflatable tube disposed along and outwardly of the peripheral wall of the frame. A screen is stretched over an opening in the frame and extends above the peripheral wall and the inflatable tube so that the inflatable tube can be brought into contact with the screen to impart tension to the screen. The inflatable tube is only inflatable in a direction transverse to the direction of the stretching of the screen and in such a manner as not to touch the holder member. A holder member is removably mounted on the screen attaching portion of the frame to sandwich the screen between the upper surface of the screen attaching portion and the lower surface of the holder member.