VENTILVORRICHTUNG.

摘要

A valve arrangement, particularly for a gas turbine engine fuel system, has a main valve control element (51) for regulating flow between an inlet (16) and an outlet (24), the control element (51) being responsive to a servo pressure in a chamber (53). The servo pressure is regulated by a valve (57) defined by a part of control element (51) and by a stem (56) of a piston (55) which is responsive to the pressure in the inlet (16) and to the pressure downsream of a variable metering device (30). The valve arrangement (50) spills fuel from upstream of the metering device (30) in such a way as to maintain the pressure difference across the metering device substantially constant.