Lock Washer (Fastener), Reference Number 3113, 1946

George Devol was a problem solver and prolific inventor, particularly in the area of automation. Around 1940, Devol developed the "Sun Switch," a photoelectric switch, to regulate light levels. Lighting for streets, factories and other public, private and business areas could be turned on and off reliably and efficiently with this device. This technical drawing defined the design requirements for one of its components.