7. Elijah McCoy (1844–1929)

Notable invention: Lubricating cup

Having worked as an oilman on a steam engine locomotive, McCoy combined his education and work experience to create a lubrication system that greased up engines and machines without having to shut them down. This would help reduce transportation times for all steam engine-based trains. As the story goes, his invention was so good, railroad engineers, trying to avoid shotty products, would ask if locomotives were outfitted with "the real McCoy". In addition to the lubricating cup, McCoy also held 57 patents.