Fuel Tank Valve Assembly With Adjustable Bypass Vent Flow

A valve assembly for a fuel tank comprising:

• a valve housing mounted to the fuel tank and defining a chamber with a vapor vent passage in communication with a vapor outlet and further defining a bypass passage in fluid communication with both the chamber and the fuel tank outside of the chamber;
• a first valve movable in the chamber toward the vapor vent passage in response to liquid fuel in the tank and configured to reduce vapor flow from the tank through the vapor vent passage when the first valve moves toward the vapor vent passage;
• and
• a second valve mounted with respect to the bypass passage at least partially outside of the chamber and configured to move independently of the first valve to vary vapor flow through the bypass passage in response to at least one operating condition in the fuel tank outside of the chamber at which the first valve has moved to reduce vapor flow through the vapor vent passage.

A multi-stage valve assembly for use with a fuel tank for controlling fluid communication from the fuel tank to a vapor outlet, comprising:

• a housing defining a chamber, a vent opening at the chamber and a bypass vent opening;
• wherein the chamber and the bypass opening are in fluid communication with the tank when at least a portion of the housing is mounted to the tank;
• a first valve within the chamber configured to permit venting from the chamber under a first set of operating conditions in the chamber, thereby establishing a first stage of the valve, and to restrict venting from the chamber under a second set of operating conditions in the chamber, thereby establishing a second stage of the valve;
• and
• a second valve configured to move independently of the first valve to adjust vapor flow from the tank through the bypass vent opening in response to a different set of operating conditions in the tank outside of the chamber.