Snap acting pneumatic diverting relay

Claim 1

IN A MAP ACTING PNEUMATIC RELAY, THE COMBINATION COMPRISING A CASING HAVING A PRESSURE CHAMBER AND A FLOW CHAMBER, MEANS DEFINING A WALL OF SAID CASING SEPARATING SAID PRESSURE AND FLOW CHAMBERS SO THAT SAID PRESSURE CHAMBER MAY BE SUBJECT TO PNEUMATIC PRESSURE INDEPENDENTLY OF PRESSURE IN SAID FLOW CHAMBER, A SIGNAL PRESSURE PORT COMMUNICATING WITH SAID PRESSURE CHAMBER, A COMMON PORT COMMUNICATING WITH SAID FLOW CHAMBER, A PAIR OF BRANCH PORTS COMMUNICATING WITH SAID FLOW CHAMBER, VALVE MEANS MOVABLY DISPOSED IN SAID FLOW CHAMBER FOR ALTERNATE CONTROL OF SAID PAIR OF BRANCH PORTS, SNAP ACTING MEANS OPERATIVE TO MOVE SAID VALVE MEANS, A PLUNGER ROD SLIDABLY EXTENDING THROUGH THE WALL OF SAID CASING BETWEEN SAID PRESSURE CHAMBER AND SAID FLOW CHAMBER WITH ONE END ENGAGING SAID SNAP ACTING MEANS, A DIAPHRAGM ELEMENT CONNECTED TO AN OPPOSITE END OF SAID PLUNGER ROD AND DEFINING A MOVABLE WALL OF SAID PRESSURE CHAMBER FOR MOVING SAID PLUNGER ROD IN RESPONSE TO SIGNAL PRESSURES IN SAID PRESSURE CHAMBER, A FIRST PLATE ELEMENT FIXED TO SAID DIAPHRAGM ELEMENT AND SAID PLUNGER ROD FOR UNITARY MOVEMENT THEREWITH, A SECOND PLATE ELEMENT SPACED FROM SAID FIRST PLATE ELEMENT, RESILIENT MEANS BETWEEN SAID FIRST AND SECOND PLATE ELEMENTS FOR BIASING SAID SECOND PLATE ELEMENT IN OPPOSITION TO SIGNAL PRESSURES IN SAID PRESSURE CHAMBER, AND MEANS FOR ADJUSTING SAID RESILIENT MEANS TO SELECT A SET POINT FOR OPERATION OF SAID VALVE MEANS BY SAID SNAP ACTING MEANS.