4. Elias Howe and the lockstitch sewing machine
Elias Howe is credited with being the inventor of a practical sewing machine. He patented the machine in 1846, the first United States patent for a lockstitch sewing machine. Almost immediately other inventors claimed to have built the first sewing machine using a lockstitch pattern, and Isaac Singer began making a competing machine, leading to a long court fight between Howe and Singer. Singer enlisted Walter Hunt, who had been making his own machines for over a decade. Hunt had never applied for a patent on his machine, though he did patent one of his later inventions, the safety pin, in 1849.
Hunt and Singer lost the court fight over patents, though the machine which the former invented in 1833 was remarkably similar to that which was patented by Howe. During the patent dispute between Howe and Singer, several other inventors claimed to have developed the sewing machine and Howe spent much of his time in court cases protecting his patent. Though Hunt could point to machines which he had built and sold well before Howe produced his, it was found that the earlier versions did not address the technical issues resolved by Howe’s machine.