Multi-function fuel metering valve.

摘要

A hybrid fuel metering system incorporating a multi-function control valve (18) is disclosed. The valve has a sleeve (96), a piston (98) mounted for translational movement within the sleeve and a spool (100) mounted for translational movement in the piston. The piston (98) has three positions for cooperating with the sleeve (96); a variable first position for metering fuel to an engine (12), a second position for directing fuel to a metering valve (20) and a third position for shutting off flow to the metering valve (20) and to the engine (12) to correct engine overspeed. The spool (100) has two positions a first position to shut off flow to the engine (12) and to the metering valve (20) to shut off the engine (12) and a variable second position to position the piston (98) to meter flow to the engine (12).