Expanded range multiple-stage metering valve

摘要

An expanded-range pintle valve comprising a plurality of stages. Each stage comprises a valve seat and head capable of regulating flow through the valve over its own dynamic range. The valve head of a higher-flow stage includes the valve seat for the next-lower flow stage. The heads and seats for the multiple stages are nested concentrically, the progressively lower-flow stages having progressively smaller diameters. All valve heads except the lowest-flow head have axial and radial bores permitting flow therethrough so that flow may be regulated first by actuating the lowest-flow stage, then by actuating successively higher flow stages. A single pintle shaft connected to a solenoid actuator is adapted to engage each of the valve heads sequentially as the actuator progresses, beginning with the lowest-flow head, thereby extending incrementally the dynamic range of the valve as each stage is successively engaged.