 Following that, he worked for electric utilities companies in Philadelphia and Spokane, as well as Detroit Edison and
Consumers Power where he learned about electrical, marine and mechanical engineering, as well as steam fittings.His first successful patented inventions, patented in 1909, were an electrothermostatic heat regulator for more effective control of stove and toaster heating elements and a thermostat for high-tension power cables.Before this, while working for the Washington Electric Company in 1906, Copeman developed a design for an electric version of the gas stoves which had been available in Britain and the USA for several decades.