Linear gaseous fuel flow controller

A fluid flow control system for regulating the flow of fluid under a range of pressures as a function of a variable input voltage, comprising:

• a proportional solenoid having a movable shaft responsive to the input voltage,
• a pressure balanced valve including,
• a fluid intake chamber having,
• an intake port, and
• an output port which comprises a valve seat and a cooperating valve disk which is connected to the shaft of the proportional solenoid,
• a fluid output chamber having a fluid discharge port and communicating with the fluid intake chamber through the said output port,
• a flexible diaphragm having a centrally disposed piston with upper and lower portions and wherein the lower portion of the piston is in contact with the valve disk,
• a pressure equalizing chamber contiguous to the diaphragm,
• conduit means interconnecting the fluid intake chamber and the pressure equalizing chamber;
• biasing means in contact with the upper portion of the piston and exerting a force thereon in a direction toward the valve disk, tending to keep the valve disk sealed against the valve seat, and
• wherein the diaphragm and piston and the valve disk are respectively sized and dimensioned so that the equal pressures existing in the intake chamber and the pressure equalizing chamber and acting on the diaphragm and the valve disk will produce a force differential that will, absent other forces acting on the disk, keep the disk closed against the valve seat, and
• wherein the force exerted by the biasing means is greater than the said differential force.