Joseph Jenckes Sr. (baptized August 26, 1599 – March 16, 1683), also spelled Jencks and Jenks, was a bladesmith, blacksmith, mechanic, and inventor who was instrumental in establishing the Saugus Iron Works in Massachusetts Bay Colony where he was granted the first machine patent in America. Jenckes was raised in a family of London cutlers and found employment west of London at a sword factory. After his wife and daughter died, and about the time the sword factory closed, he left his only surviving child with family and immigrated to New England.