rising hinge
A form of gravity hinge so constructed that when the door to which it is attached is opened the door is lifted somewhat from the floor so as to pass over a rug, carpet, or other obstruction, and will also have a tendency to close itself. The use of thresholds or saddles in doorways makes this device less essential. Hinges for blinds are sometimes so constructed in the U.S. that they rise only in process of opening or shutting and fall back into normal place not only when they are fully closed but fully open. This device is intended to take the place of ordinary fastenings used to prevent the blind from being blown by the wind when opened back against the outside wall. Usually a butt hinge. A common form has the joints of the knuckle oblique so that, when turned, the moving flap rises on the other. (Sturgis, 1900)