While he was not as well-known as others, Lemelson, known as "Jerry," was one of the most prolific inventors of the 20th century, with some 600 patents to his credit for products like automated warehouses, industrial robots, cordless telephones, fax machines, videocassette recorders, camcorders and the magnetic tape drive used in Sony’s Walkman tape players. Lemelson also made a name for himself-not always in a positive way-as a defender of inventor’s rights, where he actively sued organizations and companies he felt had infringed upon his patents. (Source)