Patent attributes
A pilot valve assembly, for operating a pressure reducing valve disposed within a fuel tank, can include a housing including a first chamber and a second chamber, a first port in fluid communication with the first and second chambers, the first port being configured to receive an atmospheric pressure, a second port in fluid communication with the first and second chambers, the second port being configured to receive a fuel tank pressure, a first pilot valve arranged within the first chamber and configured to open only when a predetermined positive pressure differential exists between the first and second ports, and a second pilot valve arranged within the second chamber and configured to open only when a predetermined negative pressure differential exists between the first and second ports.