High pressure actuated metal seated diaphragm valve

An automatically actuatable diaphragm valve for high pressure gas lines, comprising:

• a metallic valve housing with an open-sided valve chamber, an inlet passage extending through said valve housing to said valve chamber and an outlet passage extending through said valve housing from said valve chamber, said valve housing being formed to include a toroidal sealing bead in said valve chamber and concentrically surrounding said inlet passage;
• a metallic diaphragm mounted in said valve housing to substantially enclose said open-sided valve chamber, said diaphragm including a central portion in juxtaposed relationship to said toroidal sealing bead, said central portion, in an unbiased condition, being dished with a concave surface facing said valve chamber and a convex surface facing outwardly from said valve chamber, said concave surface being substantially concentric with said toroidal sealing bead and spaced therefrom for permitting gas flow through said inlet passage, into said valve chamber and out of said outlet passage;
• a valve stem axially movable relative to said valve housing toward and away from said diaphragm;
• a diaphragm actuator button disposed between said valve stem and said diaphragm, said diaphragm actuator button having an outer face floatably engaged with said valve stem for movement transverse to the axial movement of the valve stem, said actuator button further having a convex inner face adjacent said outer surface of said diaphragm;
• and
• an actuator for selectively and non-rotatably moving said valve stem toward and away from said diaphragm, whereby movement of said valve stem toward said diaphragm urges said inner surface of said diaphragm into sealing engagement with said toroidal sealing bead and urges said outer surface of said diaphragm into a concave shape concentrically within said toroidal sealing bead, and whereby said diaphragm actuator button floats transversely into substantially concentric alignment with said toroidal sealing bead as said outer surface of said diaphragm deflects into said concave shape.