Vacuum filter

Claim 2

A VACUUM FILTER HAVING, IN COMBINATION, A TANK ADAPTED TO CONTAIN A BODY OF LIQUID TO BE FILTERED MAINTAINED AT A PREDETERMINED LEVEL, A HOLLOW RIGID DRUM DEFINING AN ANNULAR CHAMBER HAVING IMPERFORATE INNER AND SIDE WALLS AND A CYLINDRICAL OUTER PERIPHERAL WALL DEFINED BY A PERFORATED AREA OCCUPYING THE MAJOR CIRCUMFERENCE THEREOF, ANOTHER ARC OF THE DRUM CIRCUMFERENCE BEING IMPERFORATE, MEANS SUPPORTING SAID DRUM IN SAID LIQUID FOR INDEXING ABOUT A FIXED HORIZONTAL AXIS COINCIDENT WITH THE AXIS OF THE DRUM AND A NORMAL FILTERING POSITION WITH SAID PERFORATED AREA AND THE END PORTIONS OF SAID IMPERFORATE AREA SUBMERGED WHILE LEAVING THE INTERMEDIATE PORTION OF THE IMPERFORATE AREA EXPOSED ABOVE SAID LIQUID LEVEL, AN ENDWISE MOVABLE WEB OF FLEXIBLE FILTER MEDIUM EXTENDING DOWNWARDLY INTO AND OUT OF SAID LIQUID AND INTO AND OUT OF CONTACT WITH SAID IMPERFORATE AREA AT POINTS DISPOSED ABOVE SAID LEVEL, SAID WEB EXTENDING AROUND SAID PERIPHERAL WALL AND COVERING ALL OF SAID PERFORATED AREA AND OPPOSITE END PORTIONS OF SAID PERFORATED AREA MEANS FOR EVACUATING SAID CHAMBER TO INDUCE STRAINING OF THE LIQUID THROUGH SAID MEDIUM AND SAID PERFORATED AREA, MEANS FOR SENSING CLOGGING OF SAID MEDIUM BY THE FILTERED OUT SOLIDS, AND MECHANISM FOR INDEXING SAID DRUM TO REMOVE THE CLOGGED WEB AND DRAW A NEW LENGTH THEREOF ONTO SAID PERIPHERAL WALL AND STOPPING THE DRUM IN SAID FILTERING POSITION WITH THE INTERMEDIATE PORTION THEREOF EXPOSED ABOVE SAID LIQUID LEVEL.

Claim 3

A VACUUM FILTER HAVING, IN COMBINATION, A TANK ADAPTED TO CONTAIN A BODY OF LIQUID TO BE FILTERED MAINTAINED AT A SUBSTANTIALLY CONSTANT LEVEL, A HOLLOW MEMBER MOVABLY MOUNTED IN SAID TANK AND PROVIDING A CHAMBER DEFINED IN PART BY A PERFORATED WALL SUBMERGED IN SAID LIQUID IN THE NORMAL FILTERING POSITION OF THE MEMBER, AN ELONGATED ENDWISE MOVABLE WEB OF A FILTER MEDIU, EXTENDING DOWNWARDLY INTO SAID LIQUID, ALONG SAID WALL TO COVER THE PERFORATIONS THEREIN AND THEN UPWARDLY AND OUT OF THE LIQUID, MEANS FOR INDEXING SAID MEMBER AND MOVING SAID WEB ENDWISE TO REMOVE THE WEB FROM SAID PERFORATED WALL AND BRING A FRESH LENGTH OF THE WEB ONTO THE WALL, A CONDUIT COMMUNICATING WITH SAID CHAMBER, A POWER DRIVEN PUMP OPERABLE TO WITHDRAWN FILTERED LIQUID OUT OF SAID CONDUIT AND SAID CHAMBER AND BUILD UP A VACUUM IN THE LATTER FOR INDUCING THE FILTERING OF A LIQUID INWARDLY THROUGH SAID WEB AND SAID PERFORATED WALL TO BUILD UP A LAYER OF FILTERED OUT SOLIDS ON THE OUTER SURFACE OF THE WEB, MECHANISM OPERABLE AFTER A PERIOD OF FILTERING THROUGH SAID WEB TO INITIATE A BLOW-BACK CYCLE INCLUDING INTERRUPTING THE WITHDRAWAL OF LIQUID FROM SAID CHAMBER BY SAID PUMP, REVERSAL OF THE FLOW OF LIQUID IN SAID CONDUIT UNTIL SAID SOLIDS HAVE BEEN RELEASED FROM THE WEB, AND THEN RESUMPTION OF THE WITHDRAWAL OF THE LIQUID FROM THE CONDUIT AND FILTERING THROUGH SAID WEB, AND MEANS FOR SENSING CLOGGING OF SAID WEB BY SAID SOLIDS AND CONTROLLING SAID MECHAISM AND SAID INDEXING MEANS TO DISSIPATE THE VACUUM IN SAID CHAMBER WHILE RETAINING THE FILTERED OUT SOLIDS ON SAID WEB, THEN INDEX SAID MEMBNER TO COVER SAID WALL WITH A NEW LENGTH OF SAID WEB AND FINALLY RESUME OPERATION OF SAID PUMP AND THE WITHDRAWAL OF LIQUID FROM SAID CHAMBER.

Claim 4

A VACUUM FILTER HAVING, IN COMBINATION, A TANK ADAPTED TO CONTAIN A BODY OF LIQUID TO BE FILTERED MAINTAINED AT A SUBSTANTIALLY CONSTANT LEVEL, A HOLLOW MEMBER MOVABLY MOUNTED IN SAID TANK AND PROVIDING A CHAMBER DEFINED IN PART BY A PERFORATED WALL SUBMERGED IN SAID LIQUID IN THE NORMAL FILTERING POSITION OF THE MEMBER, AN ELONGATED ENDWISE MOVABLE WEB OF A FILTER MEDIU, EXTENDING DOWNWARDLY INTO SAID LIQUID, ALONG SAID WALL TO COVER THE PERFORATIONS THEREIN AND THEN UPWARDLY AND OUT OF THE LIQUID, MEANS FOR INDEXING SAID MEMBER AND MOVING SAID WEB ENDWISE TO REMOVE THE WEB FROM SAID PERFORATED WALL AND BRING A FRESH LENGTH OF THE WEB ONTO THE WALL, A CONDUIT COMMUNICATING WITH SAID CHAMBER, A POWER DRIVEN PUMP OPERABLE TO WITHDRAWN FILTERED LIQUID OUT OF SAID CONDUIT AND SAID CHAMBER AND BUILD UP A VACUUM IN THE LATTER FOR INDUCING THE FILTERING OF A LIQUID INWARDLY THROUGH SAID WEB AND SAID PERFORATED WALL TO BUILD UP A LAYER OF FILTERED OUT SOLIDS ON THE OUTER SURFACE OF THE WEB, MECHANISM OPERABLE AFTER A PERIOD OF FILTERING THROUGH SAID WEB TO INITIATE A BLOW-BACK CYCLE INCLUDING INTERRUPTING THE WITHDRAWAL OF LIQUID FROM SAID CHAMBER BY SAID PUMP, REVERSAL OF THE FLOW OF LIQUID IN SAID CONDUIT UNTIL SAID SOLIDS HAVE BEEN RELEASED FROM THE WEB, AND THEN RESUMPTION OF THE WITHDRAWAL OF THE LIQUID FROM THE CONDUIT AND FILTERING THROUGH SAID WEB, AND MEANS FOR SENSING CLOGGING OF SAID WEB BY SAID SOLIDS AND CONTROLLING SAID MECHAISM AND SAID INDEXING MEANS TO DISSIPATE THE VACUUM IN SAID CHAMBER WHILE RETAINING THE FILTERED OUT SOLIDS ON SAID WEB, THEN INDEX SAID MEMBNER TO COVER SAID WALL WITH A NEW LENGTH OF SAID WEB AND FINALLY RESUME OPERATION OF SAID PUMP AND THE WITHDRAWAL OF LIQUID FROM SAID CHAMBER.