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.
Partridge Wilson Engineering
In February 1937, they produced what they claimed was the first all-electric mobile fish-and-chips saloon. Beneath a serving counter was an oven, which was fitted with two sets of electric elements. One set could be plugged into a mains electrical socket, and was used to bring the oven up to temperature. Once it was hot, the second set were powered from the vehicle's battery, but the amount of current drawn was somewhat lower, as it only had to maintain the temperature. Two months later, they showcased a mobile milk bar, complete with egg-whisking machines, fountains and a refrigerator, again powered from the vehicle battery. A milk tank held of milk. Later in the year they held a competition for ideas to improve or develop their products. Prizes of 10, 5 and 3 guineas were offered.