GB773700A - - Google Patents

Abstract

773,700. Ignition systems construction and arrangement of sparking plugs. ECONOMY ENGINE CO. March 1, 1955 [March 9, 1954], No. 6017/55. Classes 7 (2) and 7 (4). In an ignition system for an engine having a combustion chamber 7, Fig. 1, with side and end walls and a recess in one of the walls and comprising at least one member positioned at least partially in the recess but externally of the chamber 7 and forming a first electrode 11, and a second member spaced from the latter and forming a second electrode 10 comprising a wall of the recess, means such as a power source 12 is electrically connected with the electrodes 10 and 11 to provide a continuous spark, i.e. a series of individual sparks which are so close together as to form a continuous spark between the electrodes. The cylinder head 5 is formed with an opening 8 near the centre thereof or between the centre and an edge of the combustion chamber 7; alternatively the opening may be located between the valves, not shown. A sparking plug 9 which is mounted in the opening 8 is hollow and defines a recess through which passes the first electrode 11, the active end thereof being in spark gap relationship with the plug body or second electrode 10; a distance of between 0.25-1 inch separates the continuous spark from the chamber 7.. The recess may be formed in the cylinder wall the electrode or electrodes being accommodated in the recess. The plug is energised by a H.V., D.C. or A.C. power source 12 ; the latter may comprise a vibrator coil or a step-up transformer. In a multicylinder engine each plug is either energized by a separate power source or from a single power source via a distributer. In a modification, the engine is additionally provided with a conventional sparking plug or plugs and ignition system. In a further modification, the sparking plug 30, Fig. 3, comprises two electrodes 31, 32 connected across a power source 35 the electrode 32 being also connected by a lead 36 to one terminal of a source 37 of H.V. unidirectional current, the other terminal of which is joined to the plug casing so generating an electrostatic field in conjunction with the continuous spark ; this system may be used alone or in combination with conventional sparking plugs and ignition systems. In any of the above embodiments a cap, not shown, may be carried by the inner end of the plug or the bushing in which the plug is mounted to offset the compression ratio reduction brought about by the use of the above plug and mounting, the cap communicating with the combustion chamber through a small opening.