Hydraulic system with shadow poppet valve

摘要

A hydraulic valve assembly includes a pilot operated proportional poppet valve in which the main poppet moves in response to pressure in a first control chamber. The pressure in a first control chamber is governed by a pilot poppet and movement of the main poppet controls fluid flow between a first inlet and a first outlet. A shadow poppet valve has a shadow poppet that controls fluid flow between a second inlet and a second outlet in response to pressure in a second control chamber. The first and second control chamber are connected together whereby the pilot operated proportional poppet valve and the shadow poppet valve open and close together. A unique hydraulic system utilizing a plurality of these hydraulic valve assemblies to operate two operators alternately in parallel or in series is described.