SPARK GAP, IN PARTICULAR FOR USE AS A PRE-SPARK GAP OF A SPARK PLUG OF AN INTERNAL COMBUSTION ENGINE

摘要

Spark arrangement for internal combustion engines for achieving a reliable ignition even of a fuel mixture which is very reluctant to ignite, by means of a small-dimension spark gap which is connected in series with a conventional spark plug. With this spark-gap a long-term constancy of operating parameters is achieved for millions of ignitions by the fact that an electrode (17) envelopes, in the manner of a sleeve, another electrode (14) so that a discharge space is formed between the electrodes, said space being linked with the casing (11) by only a narrow gap (18). The gas discharge is stabilized locally at a point which is as far as possible from the gap (18), for example by means of an emission-promoting activation material (16) of the front face of the inner electrode (14), so that the emergence of disintegrated electrode material from the gap (18) is prevented, as well as its deposition on the wall of the casing, and the operating parameters of the spark gap remain unchanged. The ignition of the spark gap in the immediate vicinity of the electrode activation material is effected by choosing a suitable geometry for the electrodes and possibly by appropriate pre-ionization.