Abstract: A source of energy (1) is connected to an energy storage circuit including a first storage capacitor (2) and a connecting element (3) for connecting the storage circuit to a discharging circuit. The discharging circuit includes in series a energy recovering inductance (4) and an ignition spark plug (5), and to terminals of which the discharging circuit there are connected free wheel diode (6) and a resistor (7) connected in parallel, so as to generate sparks between the electrodes of the spark plug. The energy storage circuit also includes a second capacitor (8) connected in parallel to terminals of the connecting element (3) and inductance element (4).

Abstract: A low-energy circuit and a high-energy circuit are operatively coupled in parallel between an energy source and an igniter. The low-energy circuit is for igniting the igniter to generate sparks between electrodes of the igniter, and the high-energy circuit is for characterizing an energy of the sparks generated between the electrodes of the igniter. A spark detector detects a presence of a spark between the electrodes of the igniter, and a control circuit enables an operation of the high-energy circuit only upon detection of the presence of a spark between the electrodes of the igniter by the spark detector.

Abstract: A high energy ignition generator includes an energy source connected to a circuit for charging an energy storage capacitor. The storage capacitor is connected to a discharge circuit consisting of a series inductive circuit for energy recovery and an ignitor having terminals to which are connected freewheel diodes. Sparks are generated between the electrodes of the ignitor, by the discharge of the capacitor in the igniter through the inductive circuit for energy recovery and by the discharge of the inductive circuit in the igniter through the freewheel diodes. The inductive circuit includes at least two inductors. The at least two inductors are connected in series with the capacitor at the time of its discharge and are connected in parallel with the terminals of the igniter at the time of their discharge.

Abstract: A spark plug for an internal combustion engine has a center electrode and at least one side electrode defining between them a spark gap. The end of the center electrode opposite the spark gap is in the form of a rod carrying a connection piece for connection to the ignition circuit. The connection piece, which is made of a metal which is a good conductor of electricity, is force-fitted on the end rod of the center electrode.

Abstract: The semi-conductive ceramic composition is obtained according to the invention from (a) a basic composition containing 40 to 80% by weight of a semi-conductor which is a silicon or boron carbide, 5 to 40% by weight of a binder or of a mixture of binders chosen from aluminum oxide, beryllium oxide, zirconium oxide, magnesium oxide, silica and silicon nitride, and 0 to 40% of a flux of a mixture of fluxes chosen from alkaline-earth carbonates and oxides, rare earth oxides and metal silicates, and (b) 5 to 40% by weight, relative to the basic composition (a), of a heat-emitting dope chosen from titanium, barium titanate, tungsten and lanthanum boride.

Abstract: This process consists in introducing a copper slug (5) into a nickel cup (1), extruding the cup-and-slug assembly and shaping it to produce a bimetallic electrode. It is characterized in that before the introduction of the said copper slug into the cup, a platinum point (2) is fixed onto the nickel cup (1). The invention applies to electrodes for electrical ignition plugs for heat engines.

Abstract: This sparking-plug for an internal combustion engine having a controlled ignition comprises a device for evacuating the heat of the earth electrode, the heat of the center electrode and the heat of the end of the nose of the insulator of the center electrode. This end of the nose of the insulator projects into the combustion chamber of the engine in which it is partly exposed to the flame front of the combustion and partly masked off by said device. The device constitutes a massive support for the earth electrode.