Abstract: A deaeration valve useful in a pressurized fluid system for reducing the transfer of air from a sump to the principal reservoir of the system is disclosed. The valve comprises a body including a bore longitudinally therethrough and a poppet-type spool slidably disposed in the bore. An orifice is axially-disposed in the end of the valve spool which is adapted to fit in the seat end of the bore. Air escapes through the orifice when an inadequate amount of fluid pressure is exerted against the orifice end of the spool to force the spool significantly away from the seat. When the spool is forced significantly away from the seat, fluid flow proceeds through a hole which communicates with the bore adjacent the seat. The spool is biased by a spring or the like against the seat, so that the pressure due to the fluid must build up to a significant value before the spool will be forced away from the seat and the hole will be open to fluid flow.

Abstract: A deaeration valve useful in a pressurized fluid system for reducing the transfer of air from a sump to the principal reservoir of the system is disclosed. The valve comprises a body including a bore longitudinally therethrough and a poppet-type spool slidably disposed in the bore. An orifice is axially-disposed in the end of the valve spool which is adapted to fit in the seat end of the bore. Air escapes through the orifice when an inadequate amount of fluid pressure is exerted against the orifice end of the spool to force the spool significantly away from the seat. When the spool is forced significantly away from the seat, fluid flow proceeds through a hole which communicates with the bore adjacent the seat. The spool is biased by a spring or the like against the seat, so that the pressure due to the fluid must build up to a significant value before the spool will be forced away from the seat and the hole will be open to fluid flow.