PROBLEMS IN IGNITION DEVELOPMENT

The author discusses in this paper a few of the problems involved in the design of ignition equipment. Some of these problems have been solved and some remain to be solved. The early history of the development of ignition apparatus is traced, reference being made to the vibrating coil type of ignition operated by dry cells or storage batteries, various types of magneto and dual-magneto systems, and combined generator and storage battery systems. The balance of the paper refers more particularly to batteries and ignition proper. The two types of battery ignition, open-circuit and closed-circuit, are described and the current characteristics of each are shown graphically by means of curves. Some of the problems encountered in the development of present battery systems are next considered and such topics as reduction of inertia in the contact-arm, overcoming harmonic vibration, advantages of one-piece cams and the function and design of the condenser are treated in detail. Problems introduced by outside factors, effect of voltage variation, automatic spark-advance mechanisms and ignition mountings are next discussed and, in conclusion, the author outlines the desirability and possibilities of standardizing ignition equipment.