Filter presses

Claim 1

A FILTER PRESS FOR THE PRODUCING OF A FILTERCAKE OF LOW MOISTURE CONTENT COMPRISING: A LONGITUDINALLY EXTENDING CHAMBER HAVING AN OPENING AT ONE END; A RIGID, PERFORATE TUBE LOCATED WITHIN SAID CHAMBER IN SUBSTANTIALLY COAXIAL RELATION THEREWITH; A FLEXIBLE BAG OF FILTER MATERIAL DISPOSED WITHIN SAID RIGID PERFORATE TUBE AND HAVING A MOUTH WHICH IS SECURED TO THE CHAMBER AT SAID OPENING THEREOF, SAID FLEXIBLE BAG BEING SUPPORTED BY SAID RIGID, PERFORATE TUBE DURING A FILTERING OPERATION; A REMOVABLE CLOSURE MEMBER ADAPTED TO CLOSE THE OPENING IN SAID CHAMBER IN PRESSURE-TIGHT MANNER; AND ELASTIC NON-POROUS BAG SECURED TO SAID CLOSURE MEMBER AND ARRANGED WITHIN AND SPACED FROM SAID FLEXIBLE BAG OF FILTER MATERIAL WHEN SAID REMOVABLE CLOSURE MEMBER CLOSES SAID OPENING, MEANS FOR INTRODUCING A PRESSURE MEDIUM INTO SAID ELASTIC NONPOROUS BAG FOR DILATING SAID ELASTIC, NON-POROUS BAG WHEREBY PRESSURE CAN BE EXERTED ON A MATERIAL TO BE FILTERED WHICH HAS BEEN INTRODUCED INTO SAID FLEXIBLE BAG OF FILTERED MATERIAL; A FIRST INLET MEANS FOR INTRODUCING THE MATERIAL TO BE FILTERED INTO THE SPACE BETWEEN THE NON-POROUS BAG AND SAID FLEXIBLE BAG; A FIRST OUTLET MEANS IN SAID CHAMBER EXTERNAL OF THE PERFORATE TUBE FOR THE DISCHARGE OF FILTRATE; A SECOND INLET MEANS FOR INTRODUCING COMPRESSED AIR INTO SAID CHAMBER EXTERNALLY OF SAID FLEXIBLE BAG OF FILTER MATERIAL TO CAUSE SAID FLEXIBLE BAG TO MOVE OUT OF SAID CHAMBER AND BE TURNED INSIDE OUT WHEN THE CLOSURE MEMBER IS REMOVED; AND A SECOND OUTLET MEANS FOR LOWERING THE PRESSURE IN SAID CHAMBER WHREBY AFTER SAID FLEXIBLE BAG OF FILTER MATERIAL HAS BEEN TURNED INSIDE OUT IT CAN BE SUCKED BACK INTO THE CHAMBER IN ITS FILTERING POSITION.