Butterfly valve device having particular seal and split-body structure

Claim 1

A BUTTERFLY VALVE COMPRISING: (A) A VALVE BODY HAVING WALLS FORMING TWO INTERSECTING PASSAGEWAYS, SAID PASSAGEWAYS BEING LOCATED IN RELATION TO EACH OTHER WHEREBY THE CENTER LINES THEREOF INTERSECT AT THE CENTER OF SAID BODY, THE INTERSECTING PORTIONS OF SAID PASSAGEWAYS DEFINING A CHAMBER WITHIN SAID BODY, (B) SAID VALVE BODY BEING FORMED OF TWO IDENTICAL HALF PORTIONS, SAID HALF PORTIONS BEING SEPARABLE ON A PARTING PLANE CONTAINING SAID CENTER, (C) A BODY FLANGE ONE EACH OF SAID HALF PORTIONS AND HAVING A FACE PARALLEL TO SAID PARTING PLANE, (D) A RESILIENT RING GASKET HAVING OPPOSITELY FACING SEALING SURFACES CONTACTING SAID BODY FLANGE FACES, (E) SAID GASKET HAVING AN INNER EDGE EXTENDING INTO SAID CHAMBER AND FORMING A CONTINUOUS RESILIENT PERIPHERAL BEAD LOCATED ADJACENT SAID WALLS, (F) A ROTATABLE VANE IN SAID CHAMBER, SAID VANE DIAMETRICALLY SUBSTANTIALLY FILLING SAID CHAMBER ON SAID PARTING PLANE, SAID VANE PRESENTING A PERIPHERAL EDGE CONTINUOUSLY CONTACTING AND SLIDABLY SEALING AGAINST SAID GASKET BEAD FOR BLOCKING FLOW THEREPAST IN CLOSED POSITION; (G) MEANS ROTATABLY MOUNTING SAID VANE IN SAID CHAMBER AND MEANS OPERATIVELY COMMUNICATING WITH SAID VANE TO PROVIDE A CONNECTION FOR APPLYING A TORQUE FOR SELECTIVELY OPENING AND CLOSING SAID VANE.