Charles Yale Knight (1868 – 1940) was an entrepreneur and inventor of the sleeve valve technology. His Knight engines would be used in the early cars, British tanks, and British aircraft. Customers included Henry Ford's competitor, John Willys and his company, Willys–Overland Motors, second largest car manufacturer after Ford Motor, as well as by Daimler, Mercedes, Peugeot and others.[1][2] He was a millionaire by the time he was 44 years of age, in 1912.