Bottom outlet valve for a mixing vessel

Claim 1

IN A HIGH-CAPACITY BOTTOM OUTLET VALVE OF THE TYPE ADAPTED TO BE MOUNTED BENEATH A MIXING VESSEL HAVING MINIMUM CLEARANCE THEREBENEATH, THE IMPROVEMENT COMPRISING IN COMBINATION: A VERTICALLY ARRANGED TUBULAR HOUSING INCLUDING A SEALED LOWER END AND AN OPEN UPPER END HAVING AN EFFECTIVE INSIDE DIAMETER CORRRESPONDING TO THE DIAMETER OF THE OUTLET PORT FOR THE MIXING VESSEL, AND CYLINDRICAL WALL SURFACE EXTENDING VERTICALLY BETWEEN THE HOUSING ENDS; MEANS SEALING THE UPPER END OF SAID HOUSING TO THE BOTTOM OF VESSEL IN COAXIAL ALIGNMENT WITH SAID VESSEL''S OUTLET PORT; MEANS DEFINING A VALVE DISCHARGE OPENING EXTENDING LATERALLY FROM THE INTERIOR OF SAID HOUSING NEAR THE UPPER END THEREOF; A CYLINDRICAL, RECIPROCATING VALVE CLOSURE MEMBER OF AN INVERTED-CUP CONFIGURATION HAVING A CLOSED UPPER END AND INCLUDING A FLAT UPPER SURFACE FACING SAID OUTLET PORT, WITH ITS EFFECTIVE OUTSIDE DIAMETER CORRESPONDING TO THE INSIDE DIAMETER OF THE UPPER END OF SAID HOUSING, AND A SKIRT-LIKE, ELONGATED DOWNWARDLY EXTENDING OUTER SIDE SURFACE DISPOSED IN SEALING CONTACT WITH THE WALL SURFACES OF SAID HOUSING FOR THEREBY DEFINING AN EXPANDABLE SEALED CHAMBER BETWEEN THE INNER SURFACE OF SAID CLOSURE MEMBER AND SAID SEALED LOWER END OF SAID HOUSING; FIRST STOP MEANS ADAPTED TO LIMIT CLOSURE MEMBER RECIPROCATING TRAVEL TO A VALVE-CLOSED POSITION, WHEREIN THE UPPER SURFACE THEREOF IS EXTENDED THROUGH SAID VESSEL''S OUTLET PORT AND DISPOSED IN A COMMON PLANE WITH THE INTERNAL BOTTOM SURFACE OF THE VESSEL, AND WHEREIN A PORTION OF SAID SIDE SURFACE OF SAID CLOSURE MEMBER IS CAUSED TO SEALINGLY ENGAGE THE SURFACE OF SAID OUTLET PORT, WHILE OTHER PORTIONS OF SAID SIDE SURFACE REMAIN IN SEALING CONTACT WITH THE WALL SURFACES OF SAID HOUSING FOR MAINTAINING A SEALED CONDITION FOR SAID CHAMBER; SECOND STOP MEANS ADAPTED TO LIMIT DOWNWARD CLOSURE MEMBER RECIPROCATING TRAVEL TO A VALVE-OPEN POSITION, WHEREIN THE UPPER FLAT SURFACE THEREOF IS LATERALLY ALIGNED WITH THE LOWER SURFACE OF SAID DISCHARGE OPENING; FLUID PRESSURIZING MEANS COMMUNICATING WITH SAID SEALED CHAMBER ADAPTED TO ESTABLISH A CHAMBER-EXPANDING PRESSURE THEREWITHIN FOR DRIVING SAID CLOSURE MEMBER TO A VALVE CLOSED POSITION, AND, SUBSEQUENTLY, TO ESTABLISH A CHAMBER-CONTRACTING PRESSURE WITHIN SAID CHAMBER FOR DRIVING SAID CLOSURE MEMBER TO A VALVEOPEN POSITION; AND VALVE-LOCKING STEMS MOUNTED ON SAID HOUSING ADAPTED TO BE SELECTIVELY EXTENDED INTO SAID HOUSING FOR ENGAGING AND MAINTAINING SAID CLOSURE MEMBER IN A VALVE-CLOSED POSITION.