Abstract: A fuel system with a fuel tank having at least one opening into an interior of the fuel tank, and an electrically operated vent valve having an inlet communicated with the interior of the fuel tank and an outlet for venting fuel vapor from the fuel tank. The vent valve is movable in response to an electric signal between an open position allowing fuel vapor through the outlet and a closed position to restrict fluid flow through the outlet. A controller is operably communicated with the vent valve to control application of an electric signal to the vent valve and thereby control at least in part the movement of the vent valve between its open and closed positions. In one embodiment the controller is responsive to a fill level in the fuel tank to control the position of the vent valve and thereby the fill level attained within the fuel tank.

Abstract: A fuel system with a fuel tank having at least one opening into an interior of the fuel tank, and an electrically operated vent valve having an inlet communicated with the interior of the fuel tank and an outlet for venting fuel vapor from the fuel tank. The vent valve is movable in response to an electric signal between an open position allowing fuel vapor through the outlet and a closed position to restrict fluid flow through the outlet. A controller is operably communicated with the vent valve to control application of an electric signal to the vent valve and thereby control at least in part the movement of the vent valve between its open and closed positions. In one embodiment the controller is responsive to a fill level in the fuel tank to control the position of the vent valve and thereby the fill level attained within the fuel tank.

Abstract: A fuel container with a wall of at least two wall shells which are separated at least partially from each other by an air gap between them. The dual shell wall structure helps to substantially improve the mechanical properties of the fuel container. Preferably, each wall shell consists of a plurality of layers of different polymeric or plastic materials. In a preferred embodiment of the invention a four layer co-extruded structure is provided; each shell comprises a layer of high density polyethylene (HDPE), a layer of filler material of treated, recycled plastics material referred to as “re-grind” and a vapor barrier layer of a plastic material substantially impermeable by hydrocarbons. The HDPE-layer may, be one surface layer of each wall shell and the vapor barrier layer is preferably the other surface layer of each wall shell. Depending on the material properties of the vapor barrier layer, an additional adhesive layer may also be necessary for connection with the adjacent layer.

Abstract: A method of forming multi-walled plastic containers in a single blow mold. In general, the method comprises disposing at least two separate parisons simultaneously into a blow mold and forming them to shape one after another by means of a special blow mandrel or pin. A substantially hollow, cylindrical first parison may be disposed around or outside of a substantially balloon or tube shaped second parison in an initially open blow mold. After closing the blow mold, the first or outer parison is expanded outwardly so that its outer surface engages the inner surface of the blow mold to assume the shape thereof, and thereafter, the second or inner parison is blown or outwardly expanded to an extent such that its outer surface at least partially engages the inner surface of the first or outer parison. The outer and inner parisons may be formed of different materials which may desirably impart different properties such as mechanical stability and resistance to permeation of fuel vapor from the container.

Abstract: A cover element and clamping ring are mountable on and sealable to close a tubular portion surrounding an access opening in a wall portion of a container of a fuel tank assembly for a motor vehicle. The tubular portion is contiguous with and projects outward from the wall portion, defines the opening in the wall portion, and has a contoured bead which projects radially outward from the projected end of the tubular portion. The cover element is demountably situated on the projected end of the tubular portion and is thereby removably situated over the opening in the container. A sealing ring is removably disposed between the cover element and the tubular portion of the container. The clamping ring is removably snapped onto the contoured bead of the tubular portion of the container.