Patent ID: 6321733
Filing Date: 2001-11-27
Classification: H01T

Abstract:
A traveling spark ignition (TSI) system for a combustion engine, comprising:an ignitor including:substantially parallel and spaced apart electrodes, including at least first and second electrodes forming a discharge gap between them, the first electrode being an outer electrode and the second electrode being an inner electrode and both electrodes having substantially circular configurations in cross-section, an outer radius of the inner electrode and an inner radius of the outer electrode being referred to as the radii of the electrodes, the length of a said electrode being relatively short with respect to the dimension of the gap and the dimension of the gap being relatively large with respect to said length, such that the ratio of the sum of the radii of said electrodes to the length of the said electrodes is larger than or equal to about four, while the ratio of the difference of these two radii to the length of the said electrode is larger than about one-third;electrically insulating material filling a substantial portion of the space between said electrodes and forming a surface between the at least first and second electrodes;an uninsulated end portion of each of said electrodes being free of said electrically insulating material and in oppositional relationship to one another;means for mounting said ignitor with said free ends of said first and second electrodes installed in a combustion cylinder of said engine; andelectrical means for providing a potential difference between said electrodes for initially providing thereto a sufficiently high first voltage for creating a channel formed of plasma between said electrodes, and a second voltage of lower amplitude than said first voltage, for sustaining a current through the plasma in said channel between said electrodes, whereby said current through the plasma and a magnetic field arising from a current flowing in at least one of the electrodes due to said current through the plasma interact in a manner creating a Lorentz force upon said plasma that, in combination with thermal expansion forces, causes it to move away from its region of origin, thereby increasing the volume of said plasma.