GB841434A - Spark producing apparatus and adaptors therefor - Google Patents

Abstract

841,434. Ignition systems. NAPIER & SON Ltd., D. July 24, 1958 [May 9, 1957], No. 14819/57. Class 7(4). A spark producing apparatus (e.g. an ignition system) comprises a main condenser 17, a charging system for the main condenser, an auto transformer 24 the secondary winding of which can be connected across a surface leakage sparking plug 29 and which has a core 25 of high permeability low eddy-current loss material, and a series spark gap for connecting the main condenser 17 when charged across the primary winding 23 of the auto transformer and a small condenser 26, as defined, in series with this primary winding. As shown the primary winding 11 is arranged for connection across a D.C. supply 12 with the interposition of a contact breaker 13 alternatively an alternating current supply may be connected across the primary winding 11 suitable materials for the core of the auto-transformer are materials such as various magnetic ferrites or compressed powdered iron. The magnetic ferrite known as Ferroxcube may be used. By "a small condenser" is meant one having a capacity which is a small fraction of that of the main condenser but which is large compared with that of the plug lead. The spark gap 18 is enclosed in a partially evacuated glass bulb. Where several sparking plugs are employed the system is associated with a jump spark distributer (Fig. 2). Ignition in gas turbines is referred to.