Patent ID: 7267137

Claim:
An automatic deadweight pressure standard comprising: a flow regulation mechanism having a flow regulator valve controlled by a first pair of non-hysteresis sylphons; a supply regulation mechanism having a supply regulator valve controlled by a second pair of non-hysteresis sylphons, the supply regulator valve automatically regulating pressure generated by an applied pressure supply source; and a mass-to-pressure transducer for transforming an applied gravitational force into a reference pressure that is generated at least within a pressure chamber; wherein the flow regulator valve automatically regulates the reference pressure generated by the mass-to-pressure transducer; wherein the flow regulator valve and the supply regulator valve are controlled so as to achieve an initial equilibrium state of pressure balance between the supply regulation mechanism and the flow regulation mechanism; wherein the first pair of non-hysteresis sylphons and the flow regulator valve are arranged such that a center of pressure force on the first pair of non-hysteresis sylphons is exerted substantially along a first reference axis, and a center of pressure force on the flow regulator valve is exerted substantially along the first reference axis; wherein the second pair of non-hysteresis sylphons and the supply regulator valve are arranged such that a center of pressure force on the second pair of non-hysteresis sylphons is exerted substantially along a second reference axis, and a center of pressure force on the supply regulator valve is exerted substantially along the second reference axis; and wherein the first reference axis could, but need not, be the same as the second reference axis.