Microwave! The history of the microwave oven! Microwave oven: when was it actually invented by Soviet scientists? Which company was the first to produce a microwave oven?

The microwave oven began to conquer the kitchens of Russians en masse relatively recently - from the mid-90s of the last century. But actually in 2017 she is seventy. Agree, without her our life would be different. Life will remind you how a microwave oven works, refresh your memory of the milestones of a long journey and deal with the myths that still surround this useful device in the kitchen.

How does a microwave oven work?

It's quite simple. The phenomenon of heating by microwave or microwave electromagnetic radiation (usually with a frequency of 2.45 GHz) of substances containing water, or more precisely, its dipole molecules (on one end there is a positive charge and on the other - a negative charge) is used.

Microwave, or ultra-high-frequency (UHF), radiation is electromagnetic waves with a length of 1 millimeter to 1 meter. Let us note that these waves also exist in nature; they are emitted by the Sun. The wavelength in a microwave oven is 12.25 cm.

Direct heating of the products occurs due to the very rapid movement of molecules under the influence of electromagnetic radiation, microwaves generated by a special emitter - a magnetron - and entering the working chamber through a sealed metal waveguide.

The electromagnetic field in which food molecules are located changes polarity almost five billion times per second, which causes the molecules to “tumble” at breakneck speed, and heat is released from friction between them.

Appearance versions

Precisely versions, because there are several of them. In addition to the official, “American” one, there are others that are less often remembered.

Daddy Spencer

Percy LeBaron Spencer is an American engineer who worked in the forties of the twentieth century at Raytheon, which is still alive and well today - the Pentagon's largest supplier, developer and manufacturer of Patriots and Tomahawks.

Spencer was then engaged in the development and manufacture of radars and their components, and one fine day, as it later turned out, for housewives all over the world, while testing another magnetron (microwave generator), he noticed how hot the sandwich, for some reason lying on the operating device, became very hot.

cooking" magnetron at one of the meetings on Raytheon's entry into the consumer market and received approval from management. So the microwave is more likely the fruit of systematic work than an accident.

The method of cooking food using microwaves was patented (patent number - 620.919), and in 1947 Raytheon introduced the first microwave oven - the Radarange. It weighed more than 300 kg, was 180 cm high, had a power of 3000 W (almost three times more than modern models), was water-cooled and cost a huge amount of money at the time - $5000 (multiply by 10–11 and get the equivalent price Nowadays).

The product was clearly not mass produced. Initially, the oven was purchased by the same US Department of Defense - for quickly defrosting food in soldiers' canteens and in the kitchens of military hospitals. Hotel and restaurant owners also showed some interest in Radarange and installed them in ship galleys.

Japanese trace

The Japanese also had a hand in “microwave cooking”. In fact, they even overtook the Americans by starting mass production of the Sharp R-10 in 1962 (demand, however, was sluggish), while in the States the first mass model appeared five years later. In 1966, Sharp developed the now familiar turntable, which significantly improved the quality of cooking and defrosting food. In 1979, the same company presented the first microwave oven with microprocessor control, and in 1999 - with access to the Internet .

Made in USSR

There is also an opinion that the birthplace of the microwave is the Soviet Union. Relatively recently, on May 17, 2011, the Trud newspaper reported that just before the start of the Great Patriotic War, on June 13, 1941, it published a note “A new method of cooking meat,” which described the installation developed at the All-Union Research Institute of Meat Industry for heat treatment meat products, using ultra-high frequency currents for this purpose.

It was a kind of prototype of a microwave oven. Perhaps, if the war had not happened a little over a week later, our country would still be considered its homeland. But everything turned out differently, and after the war the USSR had no time for microwaves.

However, much later, in the 80s of the twentieth century, our country had its own production of microwave ovens from Japanese components: at the ZIL (Moscow) and Yuzhmash (Donetsk) factories.

Alien visitor

For dessert - a version about the alien origin of the microwave oven. There is one. According to it, the technology was borrowed by the Americans from aliens as a result of the famous Roswell incident. In 1947, an alleged UFO crashed or was shot down in New Mexico (the US Air Force does not officially confirm this when talking about a weather balloon). And there, on board an alien ship, along with immediately classified aliens, they allegedly found our heroine - a microwave oven, in any case, the technological solutions that formed the basis of her work.

Of course, there is no official confirmation of this version. The Roswell incident is now more of a part of American pop culture, although there are still debates about how it really happened, whether it was aliens or a secret military experiment.

Massive conquest of kitchens

Microwaves took their first steps into American homes in 1955, when local household appliance manufacturer Tappan (later purchased by Electrolux), using Raytheon's own developments and technologies, introduced a version of the microwave oven for home use. But these steps are still timid - the device still turned out to be cumbersome, still unclear to Americans, and although it cost less, it was still expensive for those times - $1,295.

The American company Litton Industries (still exists today - the largest manufacturer of military equipment in the United States) also did a lot in the middle of the last century to promote microwaves to the masses. It is Litton that we owe for the appearance of models of the format that is now considered a classic: small in height, but relatively wide and deep.

The first truly popular microwave appeared in the United States in 1967 and was a joint product of Raytheon and Amana. It cost about 400 dollars. It was 50 years ago that the microwave boom began in the United States. By 1975, sales of microwave ovens were already about 1 million units per year.

At first, Japan was ahead of the United States in percentage terms in the distribution of microwave ovens. In the early 70s, already 17% of Japanese families used a microwave oven at home on a daily basis, and in the USA - only 4%. But within a few years, such stoves were working in the kitchens of 14% of American families. By the end of the seventies, it was already in more than 50% of kitchens in the United States and overtook the dishwasher in popularity.

The microwave oven is the savior of many modern kitchens. For those who live a hectic life and suffer from lack of time, this is a great find.

We no longer have to stand near the stove and wait for hours for our dinner to cook. Now we can simply cook and heat up ready-made dishes in the microwave, and watch how it spins on a special dish for some time.

There is a wide, impressive and actually quite tasty selection of foods on the market that can be quickly cooked in these ovens in a matter of minutes.

A Brief History of the Microwave Oven:

The invention of the microwave was not something out of the ordinary that happened in isolation - it was an adaptation and fusion of previous technologies.

It has quite an interesting and exciting history. It was during World War II that two scientists invented the magnetron - essentially a tube that produced microwaves. The magnetron was used in the British radar system to allow microwaves to identify Nazi planes heading to Britain on bombing campaigns.

Happy accident

It was only a few years later that it was discovered that these microwaves could actually cook food. In 1946, Dr. Percy Spencer, a self-taught engineer with the Raytheon Corporation, was conducting a research project in the field of radar. When he was experimenting with a new magnetron, it fell on the scientist’s pocket containing chocolate, and as a result it melted.

He tried another experiment by placing popcorn cubes next to a tube - the result was that they popped up all over his laboratory. He conducted a similar experiment with an egg that was cooked and then exploded before his eyes.

It was a springboard for further scientific curiosity and experimentation: could microwaves be used to cook other foods?

The idea was quickly adopted by engineers who were interested in making sure Spencer's newly discovered capabilities were useful and practical. The patent was filed in October 1945 for a microwave oven that heated food using microwave energy.

This led to the creation of the first microwave oven, the Radarange, in 1947. It was a large stove, 6 feet (1.8 m) tall, weighed 750 pounds (340 kg), and cost just over $5,000.

Modifications were made such that in 1954 a model was sold that used 1600 watts and sold for $2000.

1967 saw the launch of a popular home microwave model priced at $495. Initial sales were slow—largely due to the high price of the appliance—but the concept became firmly ingrained in the public's mind, and the reality and practicality of fast cooking actually emerged.

Modification Matter

Further changes were made to microwave oven design in the 60s. Unveiled at the Chicago trade show, the microwave oven received even more exposure and generated further interest and popularity, with US unit sales rising to over a million by the mid-70s.

The microwave was even more popular in Japan and sales were faster - they were able to make less expensive units by reverse engineering the cheaper magnetron.

A combination of further mastering and developments in technology resulted in a microwave oven that was ultimately a higher quality, smoother, more efficient product and at a price that was more affordable for the average consumer's pocket.

Warnings and Myths

As with any new technology or invention, there is always a certain degree of suspicion, doubt and even fear - and the microwave was no exception.

Radiation poisoning, impotence, infertility, brain damage and blindness were blamed on the latest kitchen technology.

However, by the mid-70s, the pros far outweighed any perceived cons, and consumers defied the naysayers (and also proved them wrong) to enjoy the benefits of microwave cooking.

Sales growth

This overwhelming wave of enthusiasm and sales meant that cooking habits around the world were changing - with an emphasis on energy efficiency and time saving. Once considered a luxury, it now seems like a necessity for the busy and fast-paced lifestyle of the modern consumer.

And by the end of the 70s, advances were made in microwave technology as prices fell sharply.

Modern microwaves

Nowadays there are microwave ovens that suit almost everyone in size, shape, design and color of every kitchen. In addition, additional functions such as grill and convection cooking mean that the microwave oven is versatile and meets the needs of the modern household in a way that would not have been possible many years ago.

Device

Main components of magnetron microwave oven:

• a metal chamber with a metallized door (in which high-frequency radiation is concentrated, for example 2450 MHz), where the heated products are placed;
• transformer - source of high-voltage power supply for the magnetron;
• control and switching circuits;
• direct microwave emitter - magnetron;
• a waveguide for transmitting radiation from the magnetron to the camera;
• auxiliary elements:
  • rotating table - necessary for uniform heating of the product from all sides;
  • circuits and circuits that provide control (timer) and safety (mode locking) of the device;
  • fan cooling the magnetron and ventilating the chamber.

Varieties

• with convection(means that the MVP can blow hot air over the product in the same way as a conventional oven).

Principle of operation

Heating in the furnace is based on the principle of the so-called “dipole shift”. A molecular dipole shift under the influence of an electric field occurs in materials containing polar molecules. The energy of electromagnetic field oscillations leads to a constant shift of molecules, aligning them according to the field lines, which is called dipole moment. And since the field is variable, the molecules periodically change direction. As they move, the molecules “sway”, collide, hit each other, transferring energy to neighboring molecules in this material. Since temperature is directly proportional to the average kinetic energy of motion of atoms or molecules in a material, this means that such mixing of molecules, by definition, increases the temperature of the material. Thus, dipole shift is a mechanism for converting the energy of electromagnetic radiation into thermal energy of a material.

Heating in a microwave oven as a result of a dipole shift under the influence of an alternating electric field depends on the characteristics of the molecules and intermolecular interactions in the medium. For better heating, the frequency of the alternating electric field must be set in such a way that the molecules have time to completely rearrange themselves during the half-cycle. Since water is contained in almost all products, the frequency of the microwave emitter of the microwave oven was selected for better heating of water molecules in the liquid state, while ice, fat and sugar heat up much worse. In ice, frozen water molecules are held in a crystal lattice, require a lower frequency for dipole shift (kilohertz instead of gigahertz, for example, 33 kHz is used to remove ice from power lines), and the radiation frequency used in a microwave oven is not optimal.

There is a common belief that a microwave oven heats food from the inside out. In fact, microwaves go from the outside to the inside and are retained in the outer layers of food, so heating a uniformly moist product occurs in approximately the same way as in an oven (to be convinced of this, just heat boiled potatoes “in their jackets,” where the thin skin sufficiently protects the product from drying out). The misconception is caused by the fact that microwaves do not affect dry non-conductive materials that are usually found on the surface of products, and therefore their heating in some cases begins deeper than with other heating methods (bread products, for example, are heated from the inside, and it is for this reason - bread and buns have a dried out crust on the outside, and most of the moisture is concentrated inside).

Furnace power

The power of microwave ovens varies from 500 to 2500 watts and above.
Almost all household ovens allow the user to adjust the level of power emitted. To do this, the heater (magnetron) is periodically turned on and off, according to the setting of the power regulator (i.e. the magnetron itself has only two states - on/off, but the longer the duration of the on state, in relation to the off state, the greater the radiated power of the furnace per unit time - the so-called pulse width modulation method). These on/off periods can be observed directly during operation of the oven (hear this in the form of changes in the noise produced by the operating oven, as well as by changes in the appearance of some products (inflating of some air products, including bags), etc. ) while turning the magnetron on and off.

Precautionary measures

Soviet microwave oven "Dnepryanka-1"

Security questions

Electromagnetic safety

Federal sanitary rules, norms and hygienic standards

Maximum permissible levels of energy flux density in the frequency range 300 MHz - 300 GHz, depending on the duration of exposure. When exposed to radiation for 8 hours or more, the maximum permissible level (MPL) is 0.025 mW/cm², when exposed to radiation for 2 hours, MPL is 0.1 mW/cm², and when exposed to 10 minutes or less, MPL is 1 mW/cm².

Myths about microwave ovens

There are claims in the press that microwave ovens (with the door removed) can be used in military affairs to inexpensively imitate radars, with the goal of forcing the enemy to spend expensive ammunition or the resources of jamming aircraft to suppress them. Typically, publications refer to the experience of the Serbian army in Kosovo.

see also

Links

• Water and microwaves

Notes

Not only microwave ovens operate on the basis of electromagnetic waves. The same principles of physics are used in telephony and radio communications. The operating process is designed in such a way that the waves accelerate water molecules, thereby allowing the food to heat up (for more details, see the article on how a microwave oven works). So who invented such an indispensable device today as a microwave oven?

Exists two versions how microwave ovens appeared in our lives. It is also interesting that they are not at all mutually exclusive, which means that both have the right to exist:

1. In the first version, the invention of microwaves is attributed to the Nazis. During hostilities, wasting time preparing food could cost lives. To solve this problem, they came up with such a device. Later, research documents and versions of the first furnaces were received by researchers from large countries, including Russia.
2. According to the second version, the invention of the microwave oven is attributed to the American engineer Percy Spencer, who proved the effect of the magnetron on food. While conducting his research, he found out that waves of a certain frequency emit a large amount of heat.

Percy Spencer - inventor of the microwave oven

Spencer filed a patent for his invention on October 8, 1945. And the first oven was produced in 1947. True, only the military used it and only for defrosting food.

Disputes between scientists and criticism of microwave ovens

For many years, the widespread use of microwave ovens remained in doubt. Scientists argued that under the influence of waves, the molecular composition of products changes, which can lead to cancer.

In their evidence, they placed particular emphasis on the fact that microwave operation requires a completely sealed space, and not a tightly closed door, which can have a detrimental effect on health.

Many studies have been conducted, the results of which were very questionable. However, negative PR is also PR, and there has been no official confirmation about the dangers of microwaves. The publications reported the following information:

1. Microwave ovens are harmful to children's dishes, since dairy products under the influence of waves become toxic and contribute to damage to the nervous system.
2. By influencing water molecules, parts of the waves remain in them and enter the human body. In the experimental subjects, hemoglobin decreased and cholesterol increased.
3. Other studies have shown that microwaves don't just stay in food, but affect and change the composition. Some experiments have shown that such changes can affect personality degeneration, as evidenced by an increase in the number of white cells in the blood and an imbalance in cholesterol levels.
4. Cholesterol is formed in any food that is prepared in microwave devices.

Experiments confirm that dishes processed in the microwave not only change, but also lose beneficial properties. According to Russian scientists, the nutritional level of foods drops to 90%.

Let's protect our citizens!

It is known that for some time microwaves were not just criticized. I wonder why in the USSR were banned microwaves? The answer to this question lies in the research and experiments of Soviet scientists who concluded that:

1. Microwaves speed up the breakdown process of substances.
2. Microwaves promote the formation of cancerous compounds in foods. This occurs through the interaction of water molecules and modified proteins.
3. Metabolism is disrupted, since the products we absorb have an unusual structure.
4. Changes in products lead to disruption of the body's protective functions.
5. Stomach problems may occur, including the formation of cancerous tumors.
6. Cancer cells appear in the blood.
7. The body stops absorbing many vitamins needed by the digestive system.
8. The microwave creates a field that is detrimental to your health.

Market Capture

Despite all the fears and publications, microwave ovens were actively produced and sold. The American inventor had no doubt about the effectiveness of his product, despite the indignation and criticism of scientists.

Here are a few stages that furnaces have gone through from their inception to the present day:

1. The first ovens were incredibly bulky and reached a height of about 1.8 meters. The devices weighed approximately 1.5 tons, which did not allow the device to be moved without assistance. Their cost was approximately $1,000, which indicated that only very wealthy citizens could afford a microwave.
2. The stoves went on sale in 1962.
3. In 1966, the stoves began to be equipped with the usual rotating stand.
4. By 1979, the furnace was already controlled by a microprocessor.
5. And in 1999, control began to be carried out by a microcomputer. Such familiar functions as grill and convection appeared, and the oven itself began to be used not only for heating, but also for cooking.

It is interesting that, despite all the intimidation of the press and scientists, by 1975 the level of microwave sales exceeded the sale of gas stoves. And in 1976, the popularity of microwaves eclipsed dishwashers.

Conclusion

All that remains is to thank Percy Spencer for creating such a miracle of electronics. After all, a modern kitchen is unthinkable without a microwave. Rumors about its harmful effects are greatly exaggerated: everything new and unknown in any case faces negative criticism. It is important that today's ovens are safe (subject to operating rules) and are simply irreplaceable in any kitchen.

The modern pace of life dictates its own rules. There are increasingly not enough hours in the day, work is not limited to sitting in the office from 9 to 18, and visits to the gym/psychologist/all kinds of courses need to be squeezed into an already busy schedule. And no one cancels the correct diet: eating 4-5 times a day is necessary for the proper functioning of internal organs and for your own comfort. After all, how much energy is wasted every day! So, so that cooking does not take much time, you need to prepare it in advance, and then simply reheat it.

In the middle of the last century, science made a revolutionary discovery - a gadget was invented for heating food as quickly as possible. Who is the brilliant person who invented it, what were its first varieties - later in the article.

Microwave oven: who created it and when?

While using any gadget, few people think about how this device was invented. But in vain. After all, the story of when this or that gadget was invented is often very interesting. At least that's what happened with the microwave oven.

Stories about who invented it and when have become legends. But one thing is certain - back in 1945, Percy LeBaron Spencer had a hand in the creation of the microwave oven during his service at Raytheon. On October 8 this year, he patented a method for heating food using electromagnetic waves. The first machine operating on this principle was released in 1947 and bore little resemblance to modern devices: it was huge, the size of a man and weighing more than 300 kg. “Radarange” is the name the developer gave it. Interestingly, the scientist Spencer received only a small monetary reward for his brainchild, and all rights to release the gadget belonged to the company in which he was registered. Only after his death was he recognized as the one who invented and patented the microwave oven. And after a while his name was included in the Inventors Hall of Fame.

The first household microwave oven and the start of mass production

From the time the first microwave oven was invented, decades passed before its mass use. There were several reasons for this:

1. High cost of equipment;
2. Criticism of this gadget by scientists;
3. As a consequence of the second point, there is negative PR for this device in the press.

Despite these obstacles, work to improve and optimize microwaves has been quite active. And already in 1962, the Sharp company launched the first conveyor production of microwave ovens (by the way, the modern analogue of this company’s oven is very different from its predecessors).

Due to harsh criticism, the first production versions of the unit were not particularly popular, but time passed and microwave ovens nevertheless captured the market. In 1966, a rotating rack was developed to heat food evenly. From the time when the very first microwave oven was released until 1979, another transformation occurred: a microprocessor control system for the device appeared, which made it much easier to use. Such microwave ovens began to actively enter the family life of those times.

Modern microwave oven

According to statistics, more than 12.6 million microwave ovens were sold in the United States in 2000 alone! In those days, when the microwave oven first appeared, no one could have thought that it would be so transformed and improved. A grill function will appear, as in the model, a food defrosting mode and a timer. It is these “goodies” that you should pay attention to when choosing a gadget for home. Even office premises equipped with a kitchen cannot do without a microwave oven. After all, saving time at lunch allows you to relax longer. As for control, microwave ovens are:

• mechanical;
• sensory.

Also, modern devices for heating food, unlike their predecessors, are equipped with a microwave protection system. Therefore, there is no need to worry about external radiation. For some, microwaves have even been able to replace ovens.

Half a century has passed from the moment the very first microwave ovens appeared to modern realities. During this time, this gadget has undergone total transformations both externally and internally. The table below provides a brief chronology of the development of this gadget:

The microwave oven was released when no one expected it. And that's a fact. We must thank Percy Spencer for inventing such an ingenious way of heating food, whether by accident or design. After all, without such an irreplaceable thing in the kitchen, the life of a modern person would be much more complicated. And no matter what they say about the supposedly harmful effects of electromagnetic waves on food, no one is going to stop using the microwave oven.