Venting means for a bag filling machine

Claim 1

APPARATUS FOR FILLING BAGS FROM A HOPPER COMPRISING A BAG FILLING MACHINE WHICH INCLUDES A CONDITIONING CHAMBER, A FILLING SPOUT DISPOSED AT THE LOWER END OF SAID CONDITIONING CHAMBER FOR FILLING A BAG, INLET MEANS FOR SAID CONDITIONING CHAMBER, A DIFFUSER PAD LOCATED AT THE BOTTOM OF SAID CONDITIONING CHAMBER FOR FLUIDIZING THE MATERIAL IN SAID CONDITIONING CHAMBER TO CAUSE SAME TO FLOW THROUGH SAID SPOUT, FIRST VALVE MEANS FOR CLOSING SAID INLET MEANS TO PREVENT REVERSE FLOW OF AIR FROM SAID CONDITIONING CHAMBER INTO SAID HOPPER, LEVEL RESPONSIVE MEANS DISPOSED IN SAID CONDITIONING CHAMBER, AND BEING OPERATIVE TO CLOSE SAID FIRST VALVE MEANS WHEN THE MATERIAL BEING FED INTO SAID CONDITIONING CHAMBER REACHES A PREDETERMINED LEVEL, SECOND VALVE MEANS DISPOSED BETWEEN SAID FILLING SPOUT AND SAID CONDITIONING CHAMBER, BAG WEIGHT RESPONSIVE MEANS FOR CLOSING SAID SECOND VALVE MEANS WHEN THE PREDETERMINED AMOUNT OF MATERIAL HAS BEEN FED INTO SAID BAG, VENT MEANS FOR SAID CONDITIONING CHAMBER, MEANS FOR RENDERING SAID VENT MEANS INOPERATIVE DURING THE TIME THAT MATERIAL IS FLOWING THROUGH SAID SPOUT, TOP AIR SUPPLY MEANS FOR SUPPLYING AIR TO THE UPPER PORTION OF SAID CONDITIONING CHAMBER WHEN SAID VENT MEANS IS INOPERATIVE, A FILTER FOR SAID VENT MEANS, SAID TOP AIR SUPPLY MEANS BEING CONNECTED TO SAID VENT MEANS SO THAT TOP AIR WILL BE CAUSED TO PASS THROUGH SAID FILTER IN THE REVERSE DIRECTION FOR CLEANING SAME, AND MEANS CONTROLLED BY THE OPERATION OF SAID WEIGHT RESPONSIVE MEANS FOR OPENING SAID VENT MEANS AND FOR CUTTING OFF SAID TOP AIR SUPPLY MEANS AT THE TIME THAT THE FLOW OF MATERIAL THROUGH SAID SPOUT IS DISCONTINUED.