Filter element assembly

Claim 1

IN AN ASSEMBLY OF FILTER ELEMENTS FOR A PRESSURE FILTER DEVICE, THE COMBINATION OF A SERIES OF CUP-SHAPED SHET METAL FILTER PLATES SUPERPOSED IN INVERTED POSITIONS AND INCLUDING A SUBSTANTIALLY HORIZONTAL WALL SURROUNDED BY A SUBSTANTIALLY VERTICAL WALL WITH A SUBSTANTIALLY HORIZONTAL FLANGE MEANS SURROUNDING SAID VERTICAL WALL, SAID PLATES BEING ARRANGED SO THAT A FILTER SPACE CONFINED WITHIN EACH FILTER PLATE OPENS DOWNWARDLY TOWAR THE TOP HORIZONTAL WALL OF THE NEXT LOWER FILTER PLATE; A RING MEMBER EXTENDING AROUND EACH OF SAID FILTER PLATES, IN CONTACT WITH THE VERTICAL WALL THEREOF AND HAVING AN UPPER EDGE FLANGED MEANS AT AN ELEVATION SLIGHTLY GREATER THAN THE TOP OF THE HORIZONTAL WALL OF SAID FILTER PLATES FOR SUPPORTING THE NEXT HIGHER FILTER PLATE; A SHEET OF FILTERING MATERIAL EXTENDING ACROSS THE BOTTOM OF EACH FILTER SPACE AND SECURED, AT ITS PERIPHERY, BETWEEN THE FLANGED MEANS OF THE RELATED FILTER PLATE AND THE FLANGED EDGE MEANS OF THE RING MEMBER SUPPORTING THE LATTER; A SEPARATOR SCREEN MEANS BELOW EACH SHEET OF FILTERING MATERIAL AND RESTING ON THE TOP SURFACE OF THE NEXT LOWER FILTER PLATE TO HOLD THE RELATED SHEET OF FILTERING MATERIAL SPACED FROM SAID TOP SURFACE OF THE NEXT LOWER FILTER PLATE; AND MEANS FOR INTRODUCING ABOVE EACH SHEET OF FILTERING MATERIAL A LIQUID TO BE FILTERED UNDER PRESSURE INTO THE CENTRAL PORTION OF THE FILTER SPACE CONFINED WITHIN EACH OF THE FILTER PLATES THE SOLIDS FILTERED FROM SAID LIQUID BEING DEPOSITED ON SAID FILTERING MATERIAL AND PROGRESSIVELY FORMING A FILTER CAKE THEREON, SAID MEANS FOR INTRODUCING A LIQUID BEING ADJACENT THE LOWER SURFACE OF THE NEXT HIGHER FILTER PLATE TO INTRODUCE SAID LIQUID ABOVE SAID SOLIDS AND SAID FILTER CAKE, SAID RING MEMBERS HAVING APERTURES THEREIN OPENING INWARDLY BELOW THE RELATED SHEET OF FILTERING MATERIAL AND ABOVE THE TOP SURFACE OF THE NEXT LOWER FILTER PLATE SO THAT THE FILTRATE PASSING THROUGH SAID SHEET OF FILTERING MATERIAL EXITS FROM THE ASSEMBLY THROUGH SAID APERTURES.