History of the Microwave Oven
Date added: 17-06-26
Category: Technology Essay
A Brief History of the Microwave Oven
|Like many of today's great inventions, the microwave oven was a by-product of another technology. It was during a radar-related research project around 1946 that Dr. Percy Spencer, a self-taught engineer with the Raytheon Corporation, noticed something very unusual. He was testing a new vacuum tube called a magnetron, when he discovered that the candy bar in his pocket had melted. This intrigued Dr. Spencer, so he tried another experiment. This time he placed some popcorn kernels near the tube and, perhaps standing a little farther away, he watched with an inventive sparkle in his eye as the popcorn sputtered, cracked and popped all over his lab.|
|The next morning, Scientist Spencer decided to put the magnetron tube near an egg. Spencer was joined by a curious colleague, and they both watched as the egg began to tremor and quake. The rapid temperature rise within the egg was causing tremendous internal pressure. Evidently the curious colleague moved in for a closer look just as the egg exploded and splattered hot yolk all over his amazed face. The face of Spencer lit up with a logical scientific conclusion: the melted candy bar, the popcorn, and now the exploding egg, were all attributable to exposure to low-density microwave energy. Thus, if an egg can be cooked that quickly, why not other foods? Experimentation began... Dr. Spencer fashioned a metal box with an opening into which he fed microwave power. The energy entering the box was unable to escape, thereby creating a higher density electromagnetic field. When food was placed in the box and microwave energy fed in, the temperature of the food rose very rapidly. Dr. Spencer had invented what was to revolutionize cooking, and form the basis of a multimillion dollar industry, the microwave oven. |
A Bit of Trivia: The "Speedie Weenie" ProjectIn the spring of 1946, Percy Spencer and an associate, P.R. Hanson (Roly Hanson), were working on a secret project they called "the Speedy Weenie". Muriel Withrow remembers the project well. She recalls, "The 'Speedy Weenie' Project was the nickname Mr. Spencer and my boss, Roly Hanson, gave to their secret project, the microwave [oven]" "'Speedie Weenie' meaning 'a quick hot dog!'" (Our thanks to Mrs. Withrow for sharing this little known detail)
Nearly 6 Feet Tall, Weighing 750 PoundsEngineers went to work on Spencer's hot new idea, developing and refining it for practical use. By late 1946, the Raytheon Company had filed a patent proposing that microwaves be used to cook food. An oven that heated food using microwave energy was then placed in a Boston restaurant for testing. At last, in 1947, the first commercial microwave oven hit the market. These primitive units where gigantic and enormously expensive, standing 5 1/2 feet tall, weighing over 750 pounds, and costing about $5000 each. The magnetron tube had to be water-cooled, so plumbing installations were also required.
Initial Reactions Were UnfavorableNot surprisingly, many were highly reluctant about these first units, and so they found only limited acceptance. Initial sales were disappointing...but not for long. Further improvements and refinements soon produced a more reliable and lightweight oven that was not only less expensive, but, with the development of a new air-cooled magnetron, there was no longer any need for a plumber. The microwave oven had reached a new level of acceptance, particularly with regard to certain industrial applications. By having a microwave oven available, restaurants and vending companies could now keep products refrigerator-fresh up to the point of service, then heat to order. The result? Fresher food, less waste, and money saved.