In 1850, Joel Houghton patented a wooden machine with a hand-turned wheel that splashed water on dishes, it was hardly a workable machine, but it was the first patent. In 1886, Josephine Cochran proclaims in disgust "If nobody else is going to invent a dishwashing machine, I'll do it myself." And she did, Josephine Cochran invented the first practical (did the job) dishwasher. Josephine Cochran had expected the public to welcome the new invention, which she unveiled at the 1893, World's Fair, but only the hotels and large restaurants were buying her ideas. It was not until the 1950s, that dishwashers caught on with the general public. Josephine Cochran's machine was a hand-operated mechanical dishwasher. She founded a company to manufacture these dish washers, which eventually became KitchenAid.
Sourced at About.com Inventors
An early Dishwasher advertisement 1896