Patent ID: 7463471

Claim:
A spark gap, comprising: two rigid discharge electrodes, fixedly mounted at a certain distance from each other; and at least two connectors, each of the two discharge electrodes being connected to one of the connectors for the purpose of connecting said electrodes to an electrical circuit comprising a current generator, wherein each of the two discharge electrodes has an elongate conducting active portion having a longitudinal connection end connectable to the connector, and an opposed longitudinal downstream end, wherein the active portions of the discharge electrodes configured such that, when an electric arc is struck: i) the electric arc is struck between the active portions of the electrodes, ii) the electric arc is struck between the active portions of the electrodes in an arc-triggering region, when the electric arc is intentionally initiated, and iii) an electric current drawn in the discharge electrodes induces, between said electrodes, a magnetic field that moves the electric arc along said active portions, and wherein at least one of the two discharge electrodes has i) at least one conducting passive portion electrically connected to the connector and/or to the active portion and with a shape configured to prevent any inopportune spontaneous striking of an electric arc under normal operating conditions of the spark gap, and ii) a useful surface having a minimum radius of curvature greater than a threshold radius below which, under the normal operating conditions of the spark gap, the intensity of the electric field between the discharge electrodes is greater than a minimum self-triggering value, said useful surface of the passive portion defined as a surface art of the passive portion facing the other of the two discharge electrodes.