A microwave oven is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range. This induces polar molecules in the food to rotate and produce thermal energy in a process known as dielectric heating. Microwave ovens heat foods quickly and efficiently because excitation is fairly uniform in the outer 25-38 mm (1-1.5 inches) of a homogeneous, high-water-content food item.
The development of the cavity magnetron in the United Kingdom 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 introduced by Tappan in 1955, but it was 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 introduced in 1967 by the Amana Corporation. After microwave ovens became affordable for residential use in the late 1970s, their use spread into commercial and residential kitchens around the world, and prices fell rapidly during the 1980s. In addition to cooking food, microwave ovens are used for heating in many industrial processes.
COMPONENTS :
high-voltage DC power source, either:
large high voltage transformer with a voltage doubler (a high-voltage capacitor and a diode)
an electronic power converter usually based around an inverter.
cavity magnetron, which converts the high-voltage DC electric energy to microwave radiation magnetron control circuit (usually with a microcontroller)
a short waveguide (to couple microwave power from the magnetron into the cooking chamber)
turntable and/or metal wave guide stirring fan
control panel
Негізгі бет DAPAT MALAMAN BAGO KA MAGREPAIR NG MICROWAVE OVEN
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