摘要 |
A gas flow controller includes a control valve coupled for actuating a main valve. In one example embodiment, a gas flow controller includes a main valve and a servo valve operated by an actuator, said servo valve being used for controlling the opening of the main valve. The servo valve is implemented in a variety of manners, such as a three-way valve means or as a double two-way valve. The servo valve further communicates, via gas pipes, with a first gas chamber limited by a diaphragm being in operative connection with the main valve, as well as to a second gas chamber in the inlet area, and a third gas chamber in the outlet area.
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