SCREEN DEVICE COMPRISING SCREEN ROLLERS FOR PREVENTING OVERSIZE GRAIN FROM JAMMING

摘要

A screen device for sorting screening material into one or more fine grain fractions and one or more oversize grain fractions. The screen device includes a frame and a roller screen including screen rollers which are arranged, such that they can be rotary-driven about a roller axis each, next to each other and which are supported on the frame and which each comprise a roller body and one or more screen structures which protrude radially relative to the roller body. There is a fine grain screen gap between the roller bodies of respectively adjacent screen rollers, through which a fine grain fraction falls, while an oversize grain fraction is conveyed on the roller screen in the axial direction of the rollers when the screen rollers are rotary-driven. The roller body of at least one of the screen rollers widens radially in the axial direction of the rollers in an axial widening portion and the width of the fine grain screen gap which the widening roller body forms with the roller body of an adjacent screen roller decreases in the axial direction of the rollers along the widening portion.