African American, Willis Johnson of Cincinnati, Ohio, patented an improved mechanical egg beater (U.S. pat# 292,821) on February 5, 1884. In fact, what Willis Johnson had really invented was an early mixing machine and not just an egg beater. Willis Johnson's device was not intended for eggs alone. Willis Johnson had designed his egg beater and mixer for eggs, batter, and other baker's ingredients. It was a double acting machine with two chambers. Batter could be beaten in one section and eggs could be beaten in another section, or one section could be cleaned while the other section could continue beating.
Willis Johnson - Egg BeaterPatent Abstract: The object of [the] ... inventors.about.com