Valve unit for modulating the delivery pressure of a gas

摘要

A valve unit for modulating the delivery pressure of a gas. The valve unit delivers a gas flow and has a servo-valve with a first closure element and a tapping duct. The valve unit further has a pressure regulator associated with the servo-valve and including a valve seat mounted in the tapping duct and a respective second closure element associated with the seat, as well as an actuator associated with the second closure element, and a control circuit for generating a control signal for the actuator. The movement of the second closure element relative to the corresponding valve seat is correlated proportionally with the actuator-control signal so that, for a pre-selected signal value, a corresponding control-pressure value is generated so as to modulate the delivery pressure in a proportionally correlated manner.