Robert Boschgmbh

Jurgen Schmatz

Werner Herden

Walter Benedikt

Siegbert Schwab

Karl-Hermann Friese

Werner Grunwald

Gerhard Heess

Hans Neu

Helmut Reum

Walter Holl

Ernst Zehender

Gerhard Liebing

Kuno Kirner

Walter Wurth

Bernd Schumacher

Adalbert Bauerle

Ludwig Barthelma

Spark plug with creepage spark gap

Surface-gap spark plug for internal combustion engines

Ignition plug for internal combustion engines

To improve the noise suppression characteristics of an ignition system for an Otto-type internal combustion engine, radio noise suppression resistors (8, 18, 22) are molded into the distributor cap (25) and electrically connected, respectively, between the tower cable connectors (19, 21, 23) on the distributor cap and the respective distributor cap terminals, which may be the peripheral terminals (16, 17) or the center wiping or sliding terminal (9) for the distributor rotor. The distributor rotor then can have a single highly conductive electrical element as a center electrode, leading to the outside peripheral rotating distributor electrode (14), which is spaced from the fixed gap electrodes by a spacing of between 0.5 to 3 mm, preferably at least 2 mm. Preferred values for the noise suppression resistors are between 1 to 5 kilo ohms.

Ignition distributor system for an internal combustion engine

In order to make possible the lower level of electrostatic disturbance that accompanies the use of a wider than usual gap in an ignition distributor without undesirable increase of the ignition pulse voltage, the distributor electrode and/or the fixed ignition circuit electrodes of the distributor are made at least in part of a material that requires less energy for pulling out an electron and has a higher secondary electron emission capability than the usual brass plate used for the contact plate at the axis of revolution of the distributor rotor, to which a carbon brush is usually provided for making contact. Alloy additions of calcium oxide or barium oxide or silicon to brass have a suitable effect and an alloy containing silicon and preferably also aluminum and calcium is preferred. The gap width is between 3 and 5 mm, preferably about 4 mm for normal motor vehicle engine application.

Wide-gap ignition distributor

The part of the distributor electrode in the breakdown region has a resistance of at least 400 ohms per millimeter. The total resistance of the electrode is in the range of between 0.5 and 1.0 kilo-ohms. The material is a mixture of a resistive ceramic material and a finely dispersed additive of metallic conductivity. Arrangements for creating surface discharge gaps thereby slowing down the sparking process and decreasing interference are also illustrated.

Electrode for ignition systems

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Mundelsheim, Germany

Jurgen Schmatz