How to make an induction heater with your own hands? Opening the induction cooker Diagram of the electrolux induction cooker

The idea of ​​heating metal with Foucault eddy currents excited by the electromagnetic field of a coil is by no means new. It has long been successfully used in industrial melting furnaces, forges, household heating devices - stoves and electric boilers. The latter are quite expensive, so home craftsmen do not give up trying to make induction heating DIY water maker. Our task is to consider workable options for home-made devices and figure out whether they can be used for heating a house.

About the principle of inductive heating

First, let's explain how electric induction heaters function. Alternating current, passing through the turns of the coil, forms an electromagnetic field around it. If you place a magnetic metal core inside the winding, it will become heated by eddy currents arising under the influence of the field. That's the whole principle.

Important condition. In order for the metal core to heat up, the coil must be powered alternating current, changing the sign and vector of the field with high frequency. When applied to the winding direct current you will receive an ordinary electromagnet.

The heating element itself is called an inductor and is the main part of the installation. IN heating boilers he is steel pipe with coolant flowing inside, and in kitchen stoves– a flat coil, as close as possible to the hob, as shown in the photo below.

The inductor coil heats the iron pipe, which transfers heat to the flowing water

The second part of the induction heater is a circuit that increases the frequency of the current. The fact is that voltage with an industrial frequency of 50 Hz is of little use for the operation of such devices. If you connect the inductor directly to the network, it will begin to hum strongly and weakly warm up the core, together with the windings. In order to effectively convert electricity into heat and completely transfer it to the metal, the frequency must be increased to at least 10 kHz, which is what the electrical circuit does.

What are the real advantages of induction boilers over heating and electrode boilers:

1. The part that heats the water is a simple piece of pipe that does not participate in electrochemical processes (as in electrode heat generators). Therefore, the service life of the inductor is limited only by the performance of the coil and can reach 10-20 years.
2. For the same reason, the element is equally good friends with all types of coolants - water, antifreeze and even machine oil, there is no difference.
3. The insides of the inductor are not covered with scale during operation.

Here the core is a utensil made of magnetic metal

Homemade device options

There are a sufficient number of various designs created for various purposes. Take a small-sized induction heater made from computer unit power supply 250-500 W. The model shown in the photo will be useful to a master in a garage or car service for melting rods made of aluminum, copper and brass.

But the design is not suitable for heating premises due to its low power. There are two on the Internet real options, whose tests and work were filmed:

• water heater from polypropylene pipe powered by welding inverter or an induction cooktop;
• steel boiler heated by the same hob.

Reference. There are others, completely homemade designs, where craftsmen assemble frequency converters from scratch. But this requires knowledge and skills in the field of radio engineering, so we will not consider them, but will simply give an example of such a circuit.

Now let's take a closer look at how to make induction heaters with your own hands, and most importantly, how they then function.

We make a heating element from a pipe

If you have been actively searching for information on this topic, you have probably come across this design, since the master posted its assembly on the popular YouTube video resource. After which many sites posted text versions of the manufacture of this inductor in the form step by step instructions. Briefly, the heater is made like this:

An important nuance. The length and cross-section of the wire for winding the coil should be determined by the standard inductor of the stove so that it matches the power field effect transistors in the electrical circuit. If you take more wire, the heating power will drop; if you use less, the transistors will overheat and fail. How it looks visually, look at the video:

As you might guess, the role of the heating element here is played by metal brushes located in the alternating magnetic field of the coil. If you run the hob at maximum, while simultaneously passing through an improvised boiler running water, then it will be possible to heat it by 15-20 °C, which is what tests of the unit showed.

Since the power of most induction cookers is in the range of 2-2.5 kW, using a heat generator you can heat rooms with a total area of ​​no more than 25 m². There is a way to increase the heating by connecting an inductor to welding machine, but there are some difficulties here:

1. The inverter produces direct current, but alternating current is needed. To connect an induction heater, you will have to disassemble the device and find the points on the diagram where the voltage has not yet been rectified.
2. You need to take a wire of a larger cross-section and select the number of turns by calculation. As an option, copper wire Ø1.5 mm in enamel insulation.
3. It will be necessary to organize cooling of the element.

The author demonstrates checking the performance of an inductive water heater in his video presented below. Tests have shown that the unit requires improvement, but the final result, unfortunately, is unknown. It looks like the craftsman left the project unfinished.

How to assemble an induction boiler

In this case, there is no need to disassemble the cheap Chinese stove. The point is to weld a boiler tank according to its dimensions, following step-by-step instructions:

1. Take steel profile pipe 20 x 40 mm with a wall thickness of 2 mm and cut blanks from it to the width of the panel.
2. Weld the tubes together lengthwise, joining the smaller sides.
3. Weld iron caps hermetically at the top and bottom to the ends. Make holes in them and install threaded pipes.
4. Attach 2 corners to one side by welding so that they form a shelf for the induction stove.
5. Paint the unit with heat-resistant spray enamel. The assembly process is shown in more detail in the video.

Final assembly and commissioning consists of mounting the boiler on the wall and inserting it into the heating system. The hob is inserted into the socket from the corners on the rear wall of the tank and connected to the mains. All that remains is to turn on the heating of the inductor.

Here you are faced with the same problem that occurred with the previous model. Undoubtedly, induction heating will work, but its power of 2.5 kW is enough to heat a couple small rooms when it's cold outside. In autumn and spring, when the temperature has not dropped below zero, a homemade boiler can heat an area of ​​35-40 m². How to properly connect it to the system, see the next video:

We deliberately presented options for induction water heaters of simple design, so that anyone could make such a unit on their own. But the question remains whether it is necessary to engage in this matter and waste your own time. There are a number of objective considerations in this regard:

1. Users who do not understand electrical and radio engineering are unlikely to be able to increase the heating power above 2.5 kW. To do this, you will have to assemble a frequency converter circuit.
2. The efficiency of the inductor is no higher than that of other electric boilers. But assembling a heater with heating elements is much easier.
3. If you don't have it lying around at home induction hob, then you will need to buy it for about 80 USD. e. This is how much cheap Chinese products cost in online stores. Ready-made ones are sold for the same money electrode boilers power up to 10 kW.
4. Electric stoves are equipped with automatic safety systems that turn off the household appliance after 1 or 2 hours of operation. This causes inconvenience during operation.
5. If, for various reasons, the coolant leaks out of a homemade heat generator, then the heating will not stop. This is fraught with fire.

Of course, you can do without expensive purchases, thoroughly understand the design and make induction heater from scratch. But you won’t be able to do everything for free, because you will need to purchase components for the circuit. Please note that the bonuses from such a heating unit are small, so it is not advisable to seriously undertake its manufacture for the purpose of heating a private home.

1. Theory.
Heating occurs due to the magnetization reversal of the ferromagnet, and not the Foucault/Eddy/eddy currents in the frying pan, because when using only Foucault currents, it will be released in the stove itself large quantity heat or the design will be very complex with copper tubes. Everything written below is taken from pdf onsemiconductor, holtek and fairchild. I haven’t tested it in practice, so I could be mistaken. Simplified diagram induction hob.

Cbus - capacitor for stabilizing the supply voltage during one period of the oscillatory process, 4...8 μF;
Cr - resonant capacitor, 0.2...0.3 µF;
Lr - inductor, 100 μH;
T1/D1 - IGBT type IHW20N120R2, FGA15N120ANTD, IRGP20B120UD (Vces=1200V/Ic=15A/Toff+Tf=400nC/Vsat=1.6 V).

I have shown what processes are taking place on this graph.

The operating cycle consists of two large stages: charging the inductor with a linearly increasing current through an open transistor/diode and a damped oscillatory process with the transistor closed. Which can be divided into several small cycles.

1. Damped oscillatory process with a closed transistor. The initial state here is always the same: Cr is charged to the Ubas level, because it is always, instantly, charged to the Ubas level when the IGBT is opened.
1. Cr is discharged to the inductor: the current through the inductor and the voltage at the IGBT collector increases to Ubas, because Uce=Ubas-Ucr.
2. The inductor discharges to Cr: The current through the inductor decreases, and the voltage at the IGBT collector increases to the maximum possible value. This value is proportional to the time the transistor is on.
3. Cr is discharged at Lr to voltage Ubas: The inductor current increases, and the IGBT collector voltage drops to 0. When the collector voltage drops below zero, the IGBT counter diode opens.
2. Linear process of pumping an inductor. The initial state here is always the same: Cr is charged to the Ubas level, because at this charge level the voltage on the counter diode passes through zero. If the unlocking pulse arrives at the transistor gate before the diode unlocks or when the diode has already closed, i.e., the resonant capacitor is not charged to Ubus or is already discharged to the inductor, then at the initial moment of time more current will pass through the transistor and it will heat up greatly. Which will have a bad effect on reliability. At this stage, Cr is always charged to the Ubas level and the collector voltage is close to 0.
   1. The inductor current passes through the counter diode: The current through the inductor drops linearly to zero. At this optimal time, apply an unlocking pulse to the gate.
   2. The inductor current flows through the IGBT: The current through the inductor increases linearly. At this time, it is necessary to close the transistor in time so that the inductor does not accumulate enough energy to breakdown the transistor at cycle 1.2.

Consequences.

1. Power is regulated by changing the duration of a burst of pulses, because PSD is difficult to regulate: the moment the transistor turns on is determined by the transition through zero of the collector voltage, and the moment it turns off is determined by the maximum possible voltage on the collector, that is, the frequency and duty cycle are related by an inverse relationship and they regulate the power in a simple way it won't work out.
2. If there are no dishes on the stove, this may damage the transistor due to an increase in the maximum voltage (Cr will charge to a higher voltage). To prevent this, every two seconds a procedure is carried out to control the presence of a frying pan: a seed pulse is applied, and then they count how many cycles the oscillatory process will decay. If more than 3, it means there are no dishes and you need to turn off the stove.
3. The heaviest is the first pulse, because then Cr is charged through the IGBT.

2. Power circuit.


Purpose of elements:
Li - a ferrite torus, placed on a network wire, serves to suppress common-mode interference. In most cases there is none;
FUSE - fuse;
C1 is a pulse noise filtering capacitor, in most cases it is not present;
R1 - resistor for discharging C1 after power off;
D1, D2 - rectifier for SMPS and network voltage control (for calculating power and overvoltage protection);
RJ - shunt in the form of a piece of thick wire;
L1 - impulse noise filter, most often there is none;
C2 - capacitor for the possibility of returning the energy of the oscillatory circuit with the inductor to the intermediate circuit of direct current Ubas;
C3 is a resonant capacitor, needed to ensure continuous current after the transistor is turned off;
Lr1 - inductor, serves to transfer energy to the dishes;
T1 - IGBT transistor, needed to convert direct current to alternating current;
R2 is a resistor designed to ensure that the transistor is in a locked state after switching on;
R3 is a resistor designed to suppress high-frequency current at the gate;
Uoutlet - rectified voltage in the network;
Ush - current control for overload protection;
Uce - voltage control on the IGBT collector, serves as overvoltage protection and, together with Ubas, determines the moment the IGBT is turned on;
Ubus - used to determine when the IGBT is turned on.

I described the theory of work earlier, so I won’t repeat it.

3. Driver.


Purpose of elements:
D2 - does not allow 18V to sag when decreasing 18V at the SMPS output; instead of a diode there may be a 51 Ohm resistor or nothing at all;
C2 - driver supply voltage stabilization, may not be present;
R3, T4, R2, T3 - two amplification stages with a common emitter;
T1 and T2 - emitter follower;
D1 - prevents the output voltage from rising above 18V;
R1 - limits the IGBT gate charge current;
R5 - increases the driver input resistance, necessary to protect the controller output;
R4 - serves to channel leakage current T4;
C1 - speeds up the switching process T4.

4. Source Switching Power 5 and 18 Volts.
They are made according to two schemes: a flyback converter and a forward converter. In both cases, the same components are used: PWM chip (PWM/PWM with a built-in switch, most often Viper12A), 78L05, transformer, resistors and capacitors.

In both schemes, S1 is a thermal fuse resting on the heat-resistant tile cover. Often it does not exist; R1 - serves for filtering (judging by the diagram in the Samsung datasheet: instead of a resistor there is a 300 µH inductor) or as a fuse (as written by stm).

4.1. Flyback converter.

4.2 Double Output Buck Converter based on the same elements.

The circuit is copied from STM (AN1514, page 3), and is used in Alaska ic1800 up to the nominal values. .


Several circuits from AN1514.

5. Voltage control on the inductor.
Despite the fact that the IGBT must be opened when the collector voltage (Uce) is slightly below zero (when the freewheeling diode built into it is open), this point in time is determined not by this voltage crossing zero, but by comparing it with the DC intermediate circuit voltage (Ubus), followed by a delay. The voltages are compared in a comparator built into the control chip.
This comparator is also used to determine the presence of a frying pan: once every 2 seconds the IGBT opens for 1 mS, and then the oscillations are counted until they are completely attenuated; if there are more than 3...24 of them, then there is no frying pan on the tile. Therefore, two dividers are used here, which bring input voltages of about 1200V to values ​​​​less than 5V (supply voltage of the control chip).
Additionally, the voltage on the collector is supplied to the analog input of the control ms for overvoltage protection. Therefore, this voltage is divided by another 1.5-3 times. Although this additional divisor may not exist.
Since a voltage of 1200V will break through any single resistor, in the upper arms of the divider they use 2 or 3 series-connected resistors of 1-2 W, but since Ubas cannot be much more than 300V, then in the upper arm of the divider there is Ubus with one or two resistors they bet less. At the output of the dividers, in series with the ic inputs there can be a 100-39000 Ohm resistor; they are probably needed for additional noise filtering. The result is the following diagram.

6. Network voltage control.
In principle, this is the same as Ubus, but measured before the rectifier. Used for power metering and overvoltage protection. For both purposes, different voltage dividers are used: the output of one divider goes to the input of the ADC, and the other to the input of the comparator. The divider circuits are similar to the previous ones. Only the voltage at the ADC input is strongly averaged by a large capacitor.


To save one large resistor, they can supply constant pressure supply from the divider connected to the ADC through a small resistor (this voltage is obviously less than 5V), and the variable through a capacitor.

7. Current control.
To control the current, an operational amplifier built into the control chip is used. That is, this circuit requires two outputs: the input of the op-amp and its output. Some tiles also use a built-in comparator for current protection. The diagram is clear without explanation.

8. Igbt temperature control.
Under the igbt, using an elastic band, the thermistor is pressed tightly. It is needed to control the temperature of the igbt.

The circuit is a regular voltage divider, in one arm of which there is an NTC thermistor of type 3950-100k.

Recommended Samsung control logic:
-temperature above 85° - reduce power;
- temperature above 90° - turn off the stove.

9. Surface temperature control.
The circuit is identical to the previous one, only the thermistor is pressed to the surface of the stove. Where is the thermistor located?

10. Tweeter and fan.
They can be controlled from separate outputs of the control chip, but in Lately They are connected to one output, but the tweeter is connected through a capacitor. Moreover, the other output of the tweeter can be connected to any voltage: 0V, 5V or 18V.

11. Other design options.
1. Circuit based on a thyristor with voltage resonance. Although it is simpler than this one, it is more reliable (no need to worry about the moment the thyristor turns off), more expensive (the resonant capacitor has a capacity 10 times larger) and heavier (the capacitors will be heavier). Now it cannot be implemented, because the industry has stopped producing inverter thyristors en masse.


2. Half-bridge resonant inverter, offered by STM.

An induction furnace is often used in the field of metallurgy, so this concept is well known to people who are to one degree or another involved in the smelting process various metals. The device allows you to convert electricity generated by a magnetic field into heat.

Similar devices are sold in stores at a fairly high price, but if you have minimal skills in using a soldering iron and know how to read electronic circuits, then you can try to make an induction furnace with your own hands.

A homemade device is unlikely to be suitable for implementation complex tasks, but will cope with basic functions quite well. The device can be assembled on the basis of a working welding inverter made of transistors, or using lamps. The most productive device is the one based on lamps due to its high efficiency.

Working principle of induction furnace

Heating of the metal placed inside the device occurs by converting electromagnetic pulses into heat energy. Electromagnetic pulses are generated by a coil with turns made of copper wire or pipes.

Scheme induction furnace and heating schemes

When the device is connected, it begins to pass through the coil. electricity, and appears around electric field changing its direction over time. The functionality of such an installation was first described by James Maxwell.

The object to be heated must be placed inside or close to the coil. The target object will be penetrated by a flow of magnetic induction, and a vortex-type magnetic field will appear inside. Thus, inductive energy will turn into thermal energy.

Varieties

Induction coil stoves are usually divided into two types depending on the type of design:

• Duct;
• Crucible.

In the first devices, the metal to be melted is located in front of the induction coil, and in the second type of furnace it is placed inside it.

You can assemble the oven by following these steps:

1. We bend the copper pipe in the form of a spiral. In total, you need to make about 15 turns, the distance between which should be at least 5 mm. The crucible should be freely located inside the spiral, where the smelting process will take place;
2. We produce a reliable housing for the device, which should not conduct electric current and must withstand high air temperatures;
3. Chokes and capacitors are assembled according to the above diagram;
4. A neon lamp is connected to the circuit, which will signal that the device is ready for operation;
5. A capacitor is also soldered to adjust the capacitance.

Use for heating

Induction furnaces of this type can also be used to heat a room. Most often they are used in conjunction with a boiler, which additionally produces heating cold water. In fact, the designs are used extremely rarely due to the fact that, as a result of losses of electromagnetic energy, the efficiency of the device is minimal.

Another drawback is based on the device’s consumption of large amounts of electricity during operation, which is why the device falls into the category of economically unprofitable.

System cooling

A device assembled independently must be equipped with a cooling system, since during operation all components will be exposed to high temperatures, and the structure may overheat and break. In store-bought ovens, cooling is done with water or antifreeze.

When choosing a cooler for your home, preference is given to options that are most profitable for implementation from an economic point of view.

For home ovens, you can try using a regular paddle fan. Please note that the device should not be placed too close to the oven, as metal parts Fans negatively affect the performance of the device, and are also capable of breaking vortex flows and reducing the performance of the entire system.

Precautions when using the device

When working with the device, you should adhere to the following rules:

• Some elements of the installation, as well as the metal that is melting, are subject to intense heat, resulting in a risk of burns;
• When using a lamp oven, be sure to place it in a closed case, otherwise there is a high risk of electric shock;
• Before working with the device, remove all metal elements and complex parts from the operating area of ​​the device. electronic devices. The device should not be used by people who have a pacemaker.

An induction type metal melting furnace can be used for tinning and forming metal parts.

A homemade installation can be easily adjusted to suit specific conditions by changing some settings. If you adhere to the indicated diagrams when assembling the structure, and also follow basic safety rules, homemade device will practically not be inferior to store-bought household appliances.

Multifunctional induction electrical appliances have been used for a long time in the metallurgy and welding industries. Their production is high technology. Improved scheme induction cooker actively used in the household industry (creation of electric stoves). Even if the equipment fails, it is not a serious problem. But specialized service centers require significant fees for their services. To save an impressive amount, you can repair your induction cooker yourself.

Components

A traditional induction hob circuit consists of several key parts, each designed to perform specific functions. Coordinated operation of the unit is achieved due to the presence of the following elements:

Principle of operation

The design of an induction cooker is not that complicated if you understand how it functions before using the product. The operation of the unit is based on electromagnetic pulses - the mechanism of current flow when the overall magnetic flux changes. In terms of its operating principle, the product is very similar to a classic transformer. Powerful coil induction type hidden under a glass-ceramic surface. IN normal conditions the mechanism interacts with current with a frequency of 20 to 200 kHz. A coil is used as the primary winding, and the secondary winding is the cookware, which the user places on top of the burner.

The induction cooker circuit is based on the fact that after placing the pan on work surface Currents come into action and perform heating. The glass-ceramic surface of the product heats up well, but only from the cookware, and not from the built-in mechanisms.

Cooking food

Absolutely all control circuits for induction cooker boards are designed for certain cookware with a magnetic bottom. The hob automatically recognizes a suitable design and is instantly activated after turning the burner. Manufacturers allow the use of the following utensils:

• Made of stainless steel.
• Cast iron.
• Enameled, but only with a flat bottom.

If the cookware itself is made of steel, but is covered with a thick layer of enamel on top, then such a product can be used.

Choosing a quality model

The circuit of a tabletop induction cooker is designed in such a way that everything depends on the voltage level in the house. If the readings are below the required values, then the main fuse near the distribution panel will regularly be knocked out, and the power cord will also burn out.

If the consumer understands that problems with voltage are still present, then it is better to study the circuit of the Endever induction cooker of lower power, which is equipped with a function for self-adjusting the required indicators. This is the simplest and most affordable option. But the heating rate of the installed container will be reduced. After purchasing the product, you need to lay the cable yourself with the appropriate cross-section. For security, you can install a separate circuit breaker with suitable rated current.

Types of faults

Recently, the Galaxy GL 3054 induction cooker has become the most popular. The repair scheme for this product is distinguished by its simplicity and affordability, due to which users do not need to spend a large amount to restore the functionality of the unit. The most common faults include:

• There is no response to the touchpad. If there is grease on the surface, the system may simply not recognize human touch. To solve this problem, it is enough to carefully clean the surface.
• Several burners do not work. You need to check the connection of the stove to the power source. Overheating may damage the inductor connector.
• The cooling fan does not turn off. The cause may be a malfunction of the temperature sensor.
• The stove does not respond to dishes. For cooking, you can only use pots and pans that were originally intended for such cooking surfaces. Otherwise, you need to check the power supply and temperature sensor.
• The residual heat indicator is not displayed. Most often, the situation arises against the background of a breakdown of the temperature sensor. When replacing the device, you need to check that the connecting wiring is securely connected to avoid a possible fire.

Restoring functionality

Single-burner induction hobs are increasingly being used in private residences and apartments. Electrical circuits allow home craftsmen to independently carry out the necessary renovation work. The first step is always to disconnect the product from the power supply. Only after this the decorative surface is dismantled to gain full access to the parts. Any traces of soot, changes in the traditional colors of elements, or signs of melting should cause concern.

Experts recommend preparing a diagram of an electric induction cooker in advance, since in this case all repair work will be completed much faster. Download required document can be found on the official website of the product manufacturer. Using a multimeter you need to check the fuse box, cable and the contacts themselves. Be sure to inspect the spirals of the induction coils. There should be no cracks on the products, as well as contact between the turns. It is necessary to test the serviceability of the connecting wiring. The circuits are checked with a multimeter. It is necessary to carefully remove the problematic burner along with the generator board. The master will have to carefully examine the element base. Burnt radio components are visible to the naked eye. When a problem is detected, the failed parts need to be replaced. In this case, a diagram of an induction cooker will help. It is not so difficult to perform all the necessary manipulations with your own hands if you prepare in advance necessary tools.

Advantages and disadvantages

The modern design of an induction cooker allows you to achieve maximum efficiency, significant energy savings, as well as minimal risks of thermal burns. The product is an excellent helper in any kitchen. The unit compares favorably with all gas and electric analogues. The main advantages of an induction cooker are noticeable even to a beginner.

The modern appearance products. The stove will organically fit into any kitchen design, and even a child can take care of it. To remove accumulated grease and other stains, use regular sponge With detergent. It is prohibited to use metal brushes and other products that may damage the surface.

After removing a frying pan or pot from the stove, the product automatically turns off, so electricity is not wasted. The food is no different from that which was cooked on regular gas. Additional conveniences include the ability to adjust temperature regime and the presence of several programs for high-quality cooking.

Disadvantages include the fact that users need to use certain cookware that is made from ferromagnetic materials. Such slabs are not immediately sold when compared with their main competitors. The average buyer cannot always afford to purchase such a product.

Safety for humans

Recently, there have been many different discussions about the level of harm of induction cookers. The operating principle of such products is based on electromagnetic fields, the negativity of which is well known to everyone. Experts have proven that at a distance of 2 cm from the stove, radiation is always higher than the permissible norm. If the pan is offset relative to the center of the burner, then the indicated norm will be overestimated in the area of ​​15 centimeters from the hob.

Quality work in residential buildings takes up a lot of free time. Before you begin installing the product yourself, you need to take into account the cross-section, phase power and number of wires power cable between hob and home switchgear. After installation, be sure to adhere to the basic operating rules and regularly clean the surface of dirt. Due to this, the stove will last for more than one year.

For many years people have been smelting metal. Each material has its own melting point, which can only be achieved using special equipment. The first furnaces for melting metal were quite large and were installed exclusively in the workshops of large organizations. Today, a modern induction furnace can be installed in small workshops when setting up jewelry production. It is small, easy to use and highly effective.

Operating principle

The melting unit of an induction furnace is used to heat a wide variety of metals and alloys. The classic design consists of the following elements:

1. Drain pump.
2. Water cooled inductor.
3. Frame made of stainless steel or aluminum.
4. Contact area.
5. The hearth is made of heat-resistant concrete.
6. Support with hydraulic cylinder and bearing unit.

The operating principle is based on the creation of Foucault eddy induction currents. As a rule, such currents cause malfunctions when operating household appliances, but in this case they are used to heat the charge to the required temperature. Almost all electronics begin to heat up during operation. This negative factor in the use of electricity is used to its full capacity.

Advantages of the device

The induction melting furnace began to be used relatively recently. The famous open-hearth furnaces, blast furnaces and other types of equipment are installed at production sites. Such a furnace for melting metal has the following advantages:

It is this last advantage that determines the spread of induction furnaces in jewelry, since even a small concentration of impurities can negatively affect the result obtained.

Depending on the design features, floor-standing and tabletop induction furnaces are distinguished. Regardless of which option was chosen, there are several basic rules for installation:

The device may become very hot during operation. That is why there should be no flammable or explosive substances nearby. In addition, according to technology fire safety close should a fire shield must be installed.

Only two types of furnaces are widely used: crucible and channel. They have similar advantages and disadvantages, the differences lie only in the method of operation used:

The most popular type of induction furnace is the crucible type. This is due to their high performance and ease of operation. In addition, if necessary, such a design can be made independently.

Homemade versions are quite common. To create them you need:

1. Generator.
2. Crucible.
3. Inductor.

An experienced electrician, if necessary, can make an inductor with his own hands. This structural element is represented by a winding of copper wire. The crucible can be purchased at the store, but a lamp circuit, a self-assembled battery of transistors, or a welding inverter are used as a generator.

Using a welding inverter

An induction furnace for melting metal with your own hands can be created by using a welding inverter as a generator. This option is the most widely used since the efforts made concern only the manufacture of the inductor:

1. Thin-walled copper tube is used as the main material. The recommended diameter is 8-10 cm.
2. The tube is bent according to the desired pattern, which depends on the characteristics of the housing used.
3. There should be a distance of no more than 8 mm between the turns.
4. The inductor is placed in a textolite or graphite housing.

After creating the inductor and placing it in the housing, all that remains is to install the purchased crucible in its place.

Such a circuit is quite complex to implement and involves the use of resistors, several diodes, transistors of various capacities, a film capacitor, copper wire with two different diameters and inductor rings. Assembly recommendations are as follows:

The created circuit is placed in a textolite or graphite case, which are dielectrics. Scheme, involving the use of transistors, quite difficult to implement. Therefore, you should undertake the manufacture of such a stove only if you have certain work skills.

Lamp stove

Lately, lamp-based stoves have been created less and less frequently, as they require careful handling. The circuit used is simpler compared to the case of using transistors. Assembly can be carried out in several stages:

The llamas used must be protected from mechanical impact.

Equipment cooling

When creating an induction furnace with your own hands, the biggest problem that arises is cooling. This is due to the following points:

1. During operation, not only the molten metal is heated, but also some elements of the equipment. That is why effective cooling is required for long-term operation.
2. The method based on the use of air flow is characterized by low efficiency. In addition, it is not recommended to install fans near the stove. This is due to the fact that metal elements can influence the eddy currents generated.

Typically, cooling is carried out by supplying water. Creating a water cooling circuit at home is not only difficult, but also economically unprofitable. Industrial versions of the furnace already have a built-in circuit, to which it is enough to connect cold water.

Safety precautions

When using an induction furnace, certain safety precautions must be followed. Basic recommendations:

When installing equipment, you should consider how the charge will be loaded and the molten metal will be extracted. It is recommended to set aside a separate prepared room for installing an induction furnace.