GB881885A - Electrical system for igniting combustible mixtures - Google Patents

Abstract

881,885. Ignition coils. ELECTRIC AUTOLITE CO. July 14, 1959, No. 24187/59. Drawings to Specification. Class 38 (2). A ignition coil for an engine ignition system (see also Group XXVII) is so arranged as to provide a very close coupling coefficient between the primary and secondary windings and the induced voltage in the primary winding is materially decreased so as to substantially reduce the duration of the objectionable arcing across the timing contacts when the energizing current is interrupted. The core of the coil may be of high-permeability steel or of material capable of carrying a very high magnetic flux per unit of cross-sectional area. A core produced by a multi-turn winding of grain-oriented high-percentage silicon steel ribbon coated to separate and hold in position its turns may be used. The primary and secondary windings are arranged in concentric relation and preferably positioned over the air gap provided in the substantially closed magnetic core. The coil should include a primary winding made for high input energizing current and have a relatively low inductance and utilize comparatively few turns with a very high turn ratio between its primary and secondary windings. The core is preferably C-shaped. Further details are given of the windings and voltages employed and dimensions of the core gap.