Walter Hunt was a mechanical genus, but his poor understanding of business and finance led him to spend his life toiling in obscurity. He invented and patented the safety pin in an effort to pay off a $15 debt. U.S. Pat. 6281, granted on April 10, 1849.
Hunt is said to have coiled an 8-inch length of brass wire at the center, and formed a clasp at the other end. Calling it a “dress pin”, Hunt sold the patent within three hours to W.R. Grace & Co. for $400 (about $10,000 in today’s dollars). The company went on to make millions from sales of the safety pin, but Hunt did not see a dime of that money.
Hunt’s other commercially important inventions were the repeating rifle, U.S. Pat. 6,663, and the sewing machine, U.S. Pat. 11,161. The rifle patent was sold off and eventually bought by Winchester. The sewing machine patent became the subject of protracted litigation, which eventually resulted in Isaac Singer agreeing to pay Hunt $50,000. But Hunt died of pneumonia in 1859 before any payments were made.