Fuel injection apparatus for gas turbine-type vehicle power plant

Claim 1

In a continuously operating fuel injection apparatus that is associated with a turbine-type vehicle power plant and is of the known type that has (a) a fuel metering valve including a displaceable control plunger which, dependent upon its position, meters fuel quantities delivered through pressure conduit means to fuel injection nozzles, (b) a device operatively connected to said control plunger for varying the position thereof and (c) a differential pressure valve positioned in the path of the fuel and communicating with said fuel metering valve to ensure a constant pressure drop therethrough independently of the metered fuel quantities, the improvement in said differential pressure valve having a given opening cross section, comprising A. a first chamber in communication with said fuel path immediately upstream of the location of metering in said fuel metering valve, B. a second chamber in communication with said fuel path immediately downstream of the location of metering in said fuel metering valve, C. a membrane separating said chambers from one another and moving in response to the pressure difference in said chambers and D. a stationary flat valve seat disposed in said pressure conduit means and cooperating with said membrane to regulate the flow of fuel from said second chamber to said pressure conduit means as a function of the pressure difference in said chambers, said flat valve seat having a plurality of throughgoing flow openings to establish communication between said second chamber and said pressure conduit means in an open position of said differential pressure valve, said flow opening being dimensioned to retain said given opening cross section and decrease the pressure cross section of said valve seat for reducing the effect of the back pressure of fuel in said pressure conduit means on said membrane.