Screening apparatus with rotary pulsing member

Claim 1

IN A SCREENING APPARTUS FOR FLUID MIXTUES OF FIBROUS MATTER AND LIQUID, ADAPTED TO SEPARATE THE FIBROUS MATTER INTO AN ACCEPTS PORTION AND A REJECTS PORTION, THE APPARATUS HAVING A SCREEN MEMBER WITH APERTURES SIZED TO PASS FIBERS ACCEPTABLE FOR PAPER MAKING, A PULSE-GENERATING ROTARY WALL MEMBER SPACED FROM THE INLET SIDE OF SAID SCREEN MEMBER, SAID SCREEN MEMBER AND SAID WALL MEMBER PROVIDING A SCREENING ZONE THEREBETWEEN THROUGH WHICH FLUID CAN PROCEED WHILE EXPOSED TO THE SCREEN MEMBER, AN INLET FOR SUPPLYING SAID MIXTURE TO SAID SCREENING ZONE, AN ACCEPTS PASSAGE FOR RECEIVING THE PORTION OF SAID MIXTURE WHICH PASSES THROUGH SAID SCREEN MEMBER, AND AN OUTLET FOR REMOVING THE REJECTS PORTION OF SAID MIXTURE FROM SAID SCREENING ZONE, THE IMPROVEMENT COMPRISING MEANS FOR CREATING A HIGH NUMBER OF SMALL LOCALIZED DISPLACEMENTS OF THE MIXTURE TO MAINTAIN THE FIBERS FLUIDIZED AND FLOWABLE WITHIN THE LIQUID WHILE THE MIXTURE IS EXPOSED TO THE INLET SIDE OF SAID SCREEN MEMBER, WHEREBY A LARGE PORTION OF THE FIBERS AND LIQUID CAN READILY PASS THROUGH SAID SCREEN MEMBER WHILE LARGER FIBROUS MATTER IS REJECTED BY SAID SCREEN MEMBER, SAID MEANS COMPRISING A MULTIPLICITY OF DISCRETE SURFACE PORTIONS OFFSET FROM THE BASE SURFACE OF SAID WALL MEMBER, SAID OFFSET SURFACE PORTIONS BEING SPACED FROM EACH OTHER AND DISTRIBUTED OVER THE SURFACE OF SAID WALL MEMBER IN A PREDETERMINED PATTERN, THE NUMBER, SIZE, SHAPE AND LOCATION OF SAID OFFSET SURFACE PORTIONS IN SAID PATTERN AND THE SPEED OF THEIR ROTATION BEING SUCH THAT THEY MOVE