Patent ID: 7352552

Claim:
A device for protection against voltage surges, comprising: a first connecting electrode in electrical connection with a first connecting pad, a second connecting electrode in electrical connection with a second connecting pad, a third mobile arc switching electrode electrically connected to the second connecting pad, an arc chute opening onto the first and second connecting electrodes, means for driving the mobile arc switching electrode with respect to the first connecting electrode from an operating position to a switching position moving away from the first connecting electrode and moving towards the second connecting electrode, so that an electric arc drawn between the first connecting electrode and the mobile arc switching electrode switches between the first connecting electrode and the second connecting electrode when the mobile arc switching electrode moves from the operating position to the switching position, an electrical ignition means connected so that when the mobile arc switching electrode is in the operating position, the electrical ignition means is connected in series between the arc switching electrode and the second connecting pad, and that when the mobile arc switching electrode is in the switching position and an electric arc is drawn between the first connecting electrode and the second connecting electrode, the electrical ignition means is disconnected from the circuit, the electrical ignition means having an ohmic resistance varying inversely with the voltage applied to the electrical ignition means, the ohmic resistance being high when the voltage is lower than an ignition voltage and decreasing when the voltage increases above the ignition voltage.