I believe you are very familiar with this operation of using a microwave oven - put cold or raw food into the microwave oven, close the oven door, press the switch, and the food will be heated in the microwave oven for a while. Comes cooked and very convenient! And it heats up faster than induction cookers and gas stoves. Why is this? How does a microwave oven work?

Characteristics of microwaves

To understand how microwave ovens work, we first need to understand a word that sounds very "scientific" - microwave. When a microwave oven heats food, it does not need to use fire. It relies on microwaves (ie high-frequency electromagnetic waves) as the heat source of the microwave oven. Microwaves are electromagnetic waves with a frequency of 300 MHz to 300,000 MHz, and a microwave oven is actually a microwave generator. The microwave frequency it generates is 2450 MHz.

Don’t worry, we won’t talk about the very “physical” concepts of frequency and wavelength here. We only need to understand that microwaves have three basic characteristics:

First, penetrability. When microwaves penetrate glass, plastic and porcelain media, they almost pass through without being absorbed. Taking advantage of this property, microwave-friendly utensils can be made from glass, ceramics and plastics.

Second, reflexivity. Microwaves will be reflected when they encounter metal materials. Taking advantage of this characteristic, the cavity and shell of the microwave oven are made of metal, and the interlayer of the observation window is made of metal mesh, which can reflect microwaves and "enclose" the microwaves in the cavity to prevent leakage to the outside.

Third, absorbency. When microwaves encounter water and food, they will be absorbed and generate heat. They can "vibrate and heat" the water molecules in the food in a short period of time to achieve the purpose of heating and cooking.

How a microwave oven works

As long as you understand the above three characteristics of microwaves, "how a microwave oven heats food" is not so mysterious! Yes, this is how it works:

First of all, there is a transformer in the microwave oven, which can convert the 220V AC output from the power socket in our home into something that can be directly used by the magnetron (remember first "magnetron" The word "tube" (oh, it plays an important role and will be tested in the exam!) directly utilizes direct current of more than 3000V; then, the core device - the magnetron generates microwaves that can heat food, and transports them to the heating chamber through the waveguide to implement heating of the food. Heating,

Microwaves generated by the magnetron in the microwave oven are "introduced" into the cooking cavity. On the one hand, the microwaves are "biubiu" reflected in the metal cavity, and on the other hand, they "penetrate" the utensils and "hit" "Food is heated internally.

Some traditional microwave ovens are equipped with a turntable. This is to rotate the food 360° and receive microwave radiation more evenly. However, many new microwave ovens without turntables on the market now use microwave stirrers (or stirrers). Microwave oven) "stirs" the microwave to radiate the food evenly. I personally feel that it is easier to clean without a turntable.

Microwave oven product structure

The main components of a microwave oven are magnetron, power transformer, oven cavity, oven door, timer and power distributor.

(1) Magnetron. The magnetron, also known as the microwave generator, is the core component of the microwave oven. It can generate and emit microwaves, the "raw material" for the operation of the microwave oven. It can generate microwaves with a vibration frequency of 2.45 billion times per second. It is invisible to the naked eye, but it can penetrate food up to 5cm deep and cause the water molecules in the food to move with it. The violent movement generates a large amount of heat energy, so the food It's "cooked".

The service life of the magnetron basically determines the service life of the microwave oven. Galanz microwave ovens use self-developed magnetrons, and their unique 7-piece radiator is durable and has a service life of up to 15 years.

(2) Power transformer. Through the transformer, the microwave oven can convert the 220V AC output from the power socket into more than 3000V DC that can be directly utilized by the magnetron.

(3) Furnace cavity. This is where the heated food is placed! The furnace cavity is surrounded by metal reflectors. The microwaves generated by the magnetron are introduced into the oven cavity and then reflected back and forth inside. During the reflection process, they come into contact with the food and transfer energy.

(4) Furnace door. The oven door is the gateway for food to enter and exit the microwave oven. It is an indispensable part of the sealed oven cavity of the microwave oven. In order to prevent microwave leakage and facilitate observation of the food in the heating oven, the oven door is made of high-temperature-resistant tempered glass and metallic glass. There is also a microwave leak-proof device.

Some people are worried about whether microwave radiation will affect them. In fact, as long as the product quality is good, the oven door components are in good condition and can be closed properly, they can rest assured!

(5) Timer and time power controller. The two functions we use most frequently, adjusting time and adjusting fire power, are both driven by motors.

Do you think it’s amazing after reading this? Microwave ovens can convert electrical energy into heat to heat food without the need for flames or coils.