Granville T. Woods
Granville T. Woods was born in Columbus, Ohio on 23 April 1856 and was the son of former slaves. He had little formal schooling when he began his career as an inventor, but apprenticed in a machine shop and learned the machinist and blacksmith trades. He then worked in a variety of transportation and industrial jobs while continuing to teach himself about electricity and mechanics, occasionally managing to get tutoring or take night courses in engineering (he eventually earned a degree).
Woods eventually settled in Cincinnati, Ohio, where he turned his attention to inventing. He received his first patent in 1884 for an improved steam boiler furnace. He licensed many subsequent mechanical inventions to the major corporations of the day.
1) Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson.
Rayvon Fouche. Baltimore, Maryland: The Johns Hopkins University Press, 2003.