The United States Patent and Trademark Office (USPTO) provide public access to the USPTO Patent Database. The USPTO Patent Full-Text Databases covers U.S. patents issued from 1790 to the present, with images, and published Patent Applications. Patents issued before 1976 are only searchable by patent number and current U.S. classification.
For patent questions, contact librarian Sarah Katz sekatz@udel.edu and check out the patent research guide for more information.