Elijah McCoy (1843 - 1929) invented an automatic lubricator for oiling steam engines in 1872. The term "the real McCoy" is believed to be a reference about the reliability of Elijah McCoy's invention.
Garrett Augustus Morgan (1877 - 1963) invented, among many other things, a 3-way automatic stop sign, which he sold to General Electric. It was used in the U.S. until the 3-light traffic sign was developed.
Otis Boykin (1920 -1982) invented electronic control devices for guided missiles, IBM computers, and the control unit for a pacemaker.
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