(under subclass 117) Subject matter consisting of a horn gap.
(1) Note. A horn gap is defined as being an air gap between two electrodes which have such a configuration that the arc, which takes place between them when the gap breaks down, is located first at a point where the electrodes are closely adjacent to each other, and then, under the action of the resulting electrical or thermal currents, rises and lengthens by shifting to a region where the distance between the electrodes is greater. Eventually, the arc ruptures because of its great length.
