If your ancestor was an inventor, you can find genealogical information in U.S. patents. The patent contains the name and address of the inventor. Other information may include citizenship and name changes.
The University of Delaware Library is a Patent and Trademark Depository Library. There is a Librarian in the Reference department who can explain patents and guide you in a patent search. For further information, see the guide to Patents.
To give you an idea of the information available, see this Extract from a patents presentation on genealogical information in patents.
The complete presentation has information on what patents are and how to find them. Credit to Dawn Rohan, Wyoming State Library.
Presentation: Patents of Invention as Genealogical Resources