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Charles F. Kettering: Science of Automotive Engineering, 1936

Electric Starter

The invention by Kettering and Deeds that led to the founding of their Dayton Engineering Laboratories Company (DELCO) plant bore similarities in principle to the cash register motor in that it provided a short, intense spurt of electricity. Since this device improved operation of the automobile, its success was assured and permanent.

Gasoline engines require the pistons to be moving before ignition takes place and so an outside agent must be used to set them in motion. Once in motion the engine's own power takes over the ignition process.

Up to that time, automobiles were started by hand cranking: a process requiring strength and reflexes. The strength was needed to turn the hand crank connected to the large flywheel and so move the crankshaft and set the engine parts in motion. Quick reflexes were necessary for the operator to step aside immediately once the engine started and avoid the dangerous and powerful "kick back" on the turning handle when the engine started and threw off the need for the crank. Henry Leland, head of the Cadillac Motor Co., had lost a friend who was injured and later died from such a "kick back." As soon as it was available, he included the new electric starter in all Cadillac models.

Kettering and Deeds recognized that the electric starter needed high initial energy to turn the flywheel and start the engine's pistons moving. Once the pistons began to move, ignition would take place in the cylinders and the engine would take over running. Their starter used the existing, low current from the car's battery, stepped it up, and created the high current and motor power which turned the flywheel and exploded the gas in the engine cylinder. Once the piston cycle was started, a relay disconnected the starter motor and the engine operated the vehicle and the battery recharging, plus other low current needs such as lighting. The electric starter was the subject of United States Patent No. 1,150,523, issued to Charles Kettering and Clyde Coleman.