Microwave oven
The development of the cavity magnetron in the UK made possible the production of electromagnetic waves of a small enough wavelength (microwaves). American engineer Percy Spencer is generally credited with inventing the modern microwave oven after World War II from radar technology developed during the war. Named the "Radarange", it was first sold in 1946. Raytheon later licensed its patents for a home-use microwave oven that was first introduced by Tappan in 1955, but these units were still too large and expensive for general home use. Sharp Corporation introduced the first microwave oven with a turntable between 1964 and 1966. The countertop microwave oven was first introduced in 1967 by the Amana Corporation. After Sharp introduced low-cost microwave ovens affordable for residential use in the late 1970s, their use spread into commercial and residential kitchens around the world. In addition to their use in cooking food, types of microwave ovens are used for heating in many industrial processes.
Slow cooker
The Naxon Utilities Corporation of Chicago, under the leadership of Irving Naxon, developed the Naxon Beanery All-Purpose Cooker for the purposes of cooking a bean meal. Naxon was inspired by a story his grandmother told about how back in her native Lithuanian town, her mother made a stew called cholent, which took several hours to cook in an oven. A 1950 advertisement shows a slow cooker called the "Simmer Crock" made by the Industrial Radiant Heat Corp. of Gladstone, NJ. The Rival Company from Sedalia, Missouri, bought Naxon in 1970, and consequentially acquired Naxon’s patent for the bean simmer cooker. Rival asked inventor Robert Glen Martin, from Boonville, Missouri, to develop Naxon’s bean cooker into a large scale production model which could cook an entire family meal, going further than just cooking a bean meal. Martin also designed and produced the mass-making machines for Rival’s manufacturing line of the Crock-Pot. The cooker was then reintroduced under the name "Crock-Pot" in 1971. Slow cookers achieved popularity in the US during the 1970s, when many women began to work outside the home. They could start dinner cooking in the morning before going to work and finish preparing the meal in the evening when they came home. In 1974, Rival introduced removable stoneware inserts, making the appliance easier to clean. The brand now belongs to Sunbeam Products, a subsidiary of Jarden Corporation. Other brands of this appliance include Cuisinart, GE, Hamilton Beach, KitchenAid, Magic Chef, West Bend Housewares, and the now defunct American Electric Corporation.