Patent attributes
A valve assembly includes a flow duct with an inlet and an outlet downstream from the inlet. A piston housing is inside the flow duct and is axially aligned with a center axis of the flow duct. A piston is inside the piston housing and is configured to extend downstream of the piston housing in a closed position. A control chamber is between the piston and an upstream end of the piston housing. A control opening extends through the upstream end of the piston housing and fluidically communicates with the flow duct and the control chamber. A cap extends through the control opening. A cap passage extends through the cap and has an inlet outside of the piston housing and an outlet inside the piston housing, and includes two ninety-degree turns between the inlet and the outlet of the cap passage.