US Patent 6941661 Folding knife

A biasing system for the blade of a folding knife includes one component or assembly applying a force tending to move the knife blade from a closed position, nested in the handle, to an open position, extending from the handle. A second component or assembly resists opening of the blade, particularly when the blade is in or near the closed position. The resisting force is overcome by the opening force after the blade has been moved through a predetermined angle relative to the handle, so that the blade then opens automatically. A safety can be actuated to block opening and/or closing of the blade. The blade can have a blunt projection upon which a user may press to move the blade through the predetermined opening angle. A clip can be provided for convenient attachment of the folding knife to an object such as a garment.