Ball valve with removable cartridge unit

Claim 1

IN A BALL VALVE; A BODY HAVING A FLOW PASSAGEWAY THERETHROUGH AND WITH SIDE WALLS FORMING A FRUSTO-CONICAL CENTRAL CHAMBER INTERRUPTING SAID PASSAGEWAY; SEAT RINGS OPPOSITELY DISPOSED IN SAID CENTRAL CHAMBER WITH INNER END PORTIONS THEREOF BEING DEFINED BY SUBSTANTIALLY CONCAVE ANNULAR SURFACES; THE OUTER END LIMITS OF THE SAID SEAT RINGS HAVING ARCUATELY EXTENDING ANNULAR SURFACES WITH A CURVATURE DEFINED BY THE BODY SURFACE FORMING THE END WALL PORTIONS OF SAID FRUSTO-CONICAL CENTRAL CHAMBER OF THE BODY; THE SAID CURVED ANNULAR SURFACES OF THE SEAT RINGS COACTING WITH SAID BODY SURFACE TO PROVIDE A FLUID SEALING CONTACT THEREWITH AROUND SAID BODY PASSAGEWAY; A PORTED SPHEROIDAL CLOSURE MEMBER INTERPOSED BETWEEN SAID SEAT RINGS AND MOUNTED FOR ROTATIONAL SLIDABLE MOVEMENT RELATIVE TO THE CONCAVE INNER END SURFACES OF SAID SEAT RINGS; SAID CLOSURE MEMBER HAVING A PORT OPENING EXTENDING THERETHROUGH IN SUBSTANTIAL AXIAL ALIGNMENT WITH THE SAID BODY FLOW PASSAGEWAY; SAID CLOSURE MEMBER HAVING CONVEX SURFACE PORTIONS NORMALLY RECEIVED WITHIN THE CONCAVE INNER END SURFACES OF SAID SEAT RINGS IN FLUID SEALING RELATION; THE CONCAVE INNER END SURFACES FORMED IN THE SAID SEAT RINGS NORMALLY HAVING A RADIUS COMMON TO EACH OTHER AND TO THE SAID CLOSURE MEMBER WHEN ASSEMBLED WITH THE LATTER MEMBER; ROTATABLE STEM MEANS HAVING AN INNER END LIMIT ENGAGEABLE BY SAID CLOSURE MEMBER TO EFFECT ROTATION OF SAID CLOSURE MEMBER; A HOLLOW PORTED PLUG MEMBER WHOLLY RECEIVED DIRECTLY ON AN OUTER SURFACE WITHIN THE BODY CENTRAL CHAMBER SUBSTANTIALLY NORMALLY NON-ROTATABLY AND ENCLOSING SAID ASSEMBLY OF SAID CLOSURE MEMBER AND SEAT RINGS WITHIN THE PORTED PORTION THEREOF; SAID STEM MEANS BEING JOURNALED IN THE PLUG MEMBER AND BEING HELD AGAINST SUBSTANTIAL ENDWISE MOVEMENT WITHIN AN OUTWARDLY OPENING RECESSED PORTION OF SAID PLUG MEMBER; REMOVABLE ATTACHMENT MEANS COOPERATING WITH SAID HOLLOW PLUG MEMBER RECESSED PORTION FOR SECURING SAID PLUG MEMBER TO SAID BODY; THE SAID PLUG MEMBER BEING OF FRUSTO-CONICAL CONFIGURATION ON SAID OUTER SURFACE RECEIVED DIRECTLY WITHIN THE BODY CENTRAL CHAMBER AND BEING MAINTAINED WITHIN SAID BODY IN FLUID SEALING RELATION THERETO BY SAID REMOVABLE MEANS THEREON COOPERATING WITH AN ANNULAR WALL CONSTITUTING SAID RECESSED PORTION OF THE PLUG MEMBER.