Diaphragm valve

Claim 1

A valve comprising: a valve housing having a passage extending therethrough, said passage having an inlet and an outlet and a longitudinal axis, said housing having a valve seat in said passage, said valve seat defining a plane which forms an acute angle with said axis, and said valve housing having a cavity communicating with said passage; a movable diaphragm extending across said cavity to define a control chamber on one side of the diaphragm, the other side of the diaphragm communicating with the passage; control means for varying the pressure in the control chamber to tend to control the position of the diaphragm, said control means including passage means in said valve housing leading to said control chamber; a diaphragm support having an opening therein; means for mounting said diaphragm support so that the diaphragm support can at least partially support the diaphragm on said other side of the diaphragm in a predetermined position of the diaphragm; a valve element; means for pivotally mounting the valve element on the valve housing for pivotal movement relative to said diaphragm support between a closed position in which the valve element engages the valve seat to essentially block the flow of fluid through the passage from the inlet to the outlet and an open position in which the valve element is spaced from the valve seat to allow the flow of fluid through the passage from the inlet to the outlet; and said diaphragm acting through said opening in said diaphragm support to urge the valve element toward the closed position when the pressure in the control chamber is sufficient and said valve element being movable to said open position by fluid from the inlet acting on said valve element when the pressure in the control chamber is reduced by said control means.