| abstract |
A microminiature valve includes a housing having a cavity, and a diaphragm having an array of a plurality of redundant, generally concentric, annular seals on an underside of the diaphragm, wherein the diaphragm is positioned within the cavity so as to define upper and lower cavity sections and wherein the array is located opposite a valve seat formed on a lower cavity surface, and wherein the valve seat incorporates a central port and a peripheral port, such that a signal fluid stream provided between the central port and the peripheral port may be controlled by displacing the annular seals to and from the valve seat, thereby respectively interrupting or permitting the flow of the signal fluid stream. The upper cavity section includes a control port for supplying a pressurized control fluid to the upper cavity and accordingly to the upper side diaphragm, so as to effect a pressure differential for movement of diaphragm with respect to the valve seat. The array includes a plurality of redundant, concentric annular seals, wherein at least one of the annular seals is sufficiently positionable for independently effecting a fluid-tight barrier to fluid flow when impressed upon the valve seat, even in the presence of a particle lodged between the valve seat and the array, such that the contemplated microminiature valve is therefore unlikely to fail when one or more fluid-borne particles becomes lodged between the valve seat and the array. The microminiature valve may be provided in a multilayer integrated assembly constructed using a planar foldable substrate and an intermediary substrate. |