Fuel capless unit having variable spring stiffness

Abstract

A capless fuel system comprises a fuel inlet body, a flapper pivotably mounted within the fuel inlet body, a biasing member associated with the flapper, an axially movable shaft associated with the biasing member, and a tension calibrator associated with the biasing member, whereby tension on the controller spring may be adjusted by the calibrator. The biasing member may be of a variety of biasing elements but is preferably a controller spring. The shaft is reversibly movable from a tensioning position in which the electromechanical driver assembly is deactivated to a tension-lowering position in which the electromechanical driver assembly is activated. The capless fuel system includes a fuel pump nozzle position sensing system. The capless fuel system relies upon a single, multi-function flapper that functions as both the capless fuel system debris cover and a sealing member to prevent evaporative emission leaks.

Dependencies are inferred from the claim text.