Very often, in the sultry heat, the room lacks at least a minimum air flow. To solve this problem, many people buy desktop fans, they are convenient and compact, some of them work from USB, that is, they can be connected to any charger, power bank or laptop, so that the coolness is always with you. But why buy something that you can do yourself from improvised means? For the readers of the site, we have prepared two simple instructions that clearly explain how to make a USB fan at home with your own hands. So, all you need to prepare is a sharp knife, good scissors, electrical tape, an unnecessary USB cable and, in fact, a homemade executive body. As for the latter, it is customary to use one of two options: an old cooler from a computer or a motor from a typewriter or other toy.
Idea # 1 - Using a cooler
It will take no more than 15 minutes to assemble the USB fan from the cooler. First you need to prepare a cooler. Two wires come out from the device - black and red, and sometimes yellow, even less often - blue. Yellow and blue are not useful to us. We clean the insulation by 10 mm and put the prepared element aside.
Next, you need to prepare a yusb wire. We cut off one half of it and clean off the insulation with a sharp knife at the cut, a clerical one is perfect. Under it you will see four wires, of which two are required: red and black. We also clean them, while the other two (usually green and white) are better cut and insulated. 
Now, as you understand, it is necessary to connect the prepared contacts in pairs, according to: red with red, black with black using twisting. After that, you need to carefully insulate the cable junction with electrical tape or heat shrink and make a stand. As for the stand, then it's already a matter of your imagination. Someone successfully uses wire, others very interestingly cut out a landing nest in a cardboard box.
After all, the homemade mini fan plugs into a computer or charger and you can enjoy your own electrical appliance.
Cooler idea
Idea number 2 - We use a motor
It will take a little more time to make a USB fan from a motor and a CD-ROM, but you can easily make such an electrical appliance with your own hands in an hour. A motor for such a homemade product should be chosen with an operating voltage of about 5 volts, a little more is possible. If you take the motor to a lower voltage, then too much current will flow through the circuit and the motor will quickly fail. 
First, we prepare all the elements of the device. In this case, you will need to make the impeller (s). 
To make it, we recommend using an ordinary CD. We draw it into 8 equal parts and carefully cut it with good scissors, almost reaching the center. Next, we warm up the disc (it is convenient to do this with a lighter), and when the plastic becomes more elastic, we bend the blades at an equal angle (as shown in the photo).
If the impeller is not bent enough, no air flow will be generated during the rotation of the disc. However, if you overdo it, then the homemade product will also work poorly and unstably.
When the blades are ready, move on to creating the main mechanism. Inside the disc, you need to insert an ordinary, cut to the desired size, champagne cork, which must be mounted on the motor shaft. Next, let's move on to creating a laptop USB fan stand. 
Here, as in the previous version, it all depends on your imagination. Of all the available tools, the option with wire is the most suitable. When the homemade USB fan is ready, we connect the wires of the motor to the wires of the yusb cord, as in the previous version, carefully insulate the twist and proceed to testing.
Hot. If I may say so, even too much. That is why you can think about how to make a fan. You will say that it can be purchased at the store. But, firstly, their cost increases significantly. Secondly, they are quickly disassembled and it is not always possible to find the necessary ones on store shelves. Therefore, here are some practical tips on how to assemble a fan. After all, it is quite possible to arrange it even at home from available materials. Here are a couple of options.
How to make a fan based on an old cooler. If there is an old one, you can take it from there. Borrow a switch there. Also, in order to make a homemade fan, you need some kind of battery holder. There are many of them, you can take it from some broken toy or something else in the same spirit. Of course, the batteries themselves will be needed in the amount of several pieces. It remains to connect all these components together, and a simple fan will be ready. If you don't want to bother with the holder, you can use a regular USB port to supply power. You can make a stand from anything. It all depends specifically on your own imagination and what you have at hand.
You can, for example, make a stand out of ordinary stiff wire fixed to something. It is not so important what kind of materials will be used, but how stable the entire structure will be.
Another option, how to make a fan, might be useful for enthusiasts. Computer disks are an excellent tool for making. What else is needed? A motor from a simple toy, a cork left over from champagne, some handy switch and a few batteries. We take the disc, and then make as many cuts as needed for the blades. It is necessary to leave about a centimeter to the inner edge. Then turn each of the blades slightly at an angle. It bends much better if the disc is heated, for example, over gas. Then you will need to insert a champagne cork into its center. If you make a small puncture in its center, for example, with an awl, then you can easily attach the entire structure to a pin. You will need to make a leg - absolutely any object in the form of a cylinder, which is able to accommodate batteries and wires, can act in its role.
It will be necessary to arrange the base for the entire unit - it can also be anything, the main thing is that it is stable and can hold the structure on itself. It only remains to add a few additional tips - when cutting out the blades, you need to make sure that each of them is about 45 degrees - about 8 pieces will eventually come out. The plug inserted in the center of the disc will need to be fixed with glue. In any case, the process should not cause you any difficulties.
If you've been thinking about how to make a fan, now you probably understand that it is very simple. Each of the proposed models is extremely easy to manufacture, and you will not need much time to create it. You do not need any special things, the above is quite enough. These fans are very convenient and compact. You can put it on your desktop. Or, if there is such a desire, take it with you to the garage or to the country house, where these devices will be the means of cooling. It is difficult to argue with the fact that they have a tangible dignity - after all, these, by and large, very useful things have been collected from various rubbish.
As you can see, it is quite possible to make a fan on your own, from scrap materials, without bothering to go to the store and search for a unit that suits you at an affordable price. Everything is much simpler.
When the hot summer days come, there can be a problem with home cooling. Not everyone has their own fan in the room. This is a rather serious problem, especially since summer has been getting hotter in recent years. Today we will tell you how to make a fan out of a cooler. In fact, there is one interesting way out of a predicament. Almost every person in the house has a lot of spare parts from a computer that can be used for their intended purpose, or you can simply build something useful out of them.
A fan from a cooler is the optimal solution to the problem of blowing a room.
A fan from a home PC cooler is the optimal solution to the problem of blowing a room. Yes, its power is not so great, but for a small room it will be enough. By the way, making a cooling fan is extremely simple. This will require some tools and materials.
Tools and materials
To work, you must necessarily acquire the following:
- a piece of cable with a USB connector;
- soldering iron;
- solder;
- flux;
- nippers;
- with a knife;
- cooler.
That's basically all you might need. These tools and materials can be replaced with others if a different type of wire connection technology is used.
Back to the table of contents
The cooler will create a flow of cold air that will bring coolness to the room.
So, now there is everything you need to carry out the work. A cooler can have many different wires, because today such computer elements are made that have their own brain. There are wires here that serve to transmit information to the device, which allows, if necessary, to increase or decrease the speed of its rotation. These elements are not needed to work. Leave only the red and black conductors. They supply power to the device. All other wires should be bitten off with wire cutters. This must be done very carefully so as not to damage those that will be involved in further work.
Next comes the USB cable. It doesn't matter if it will be working or if some of the wires are missing, the most important thing is that there are also red and black wires here. The rest should be cut off, although they may simply not be used, but for an easier subsequent connection to the cooler, it is still better to remove them. This is also done using the most ordinary nippers. So, two cables are prepared, which means that you can safely proceed to the next stage of the work. It is worth remembering that it is the USB connector that is used for power. A standard 220-volt outlet is inappropriate here, since the operating voltage of the cooler is standard for a personal computer and completely coincides with that given by USB.
The most important thing about a USB cable is that it contains the red and black wires needed to make the fan.
The next step is to strip the red and black wires. This can be done with the help of all the same nippers, or you can use an ordinary knife. Here everyone does the work as it seems more convenient to him. The stripped wires must be twisted to form a single wire. Next, each end should be irradiated. To do this, you will have to use a soldering iron, solder and flux. The device must be preheated. For this, the soldering iron is plugged into a standard 220 Volt socket. For its full heating, it is worth waiting for about 10 minutes, although in this situation everything directly depends on its power. The higher it is, the less time you have to wait. When the soldering iron has warmed up, it should first be dipped into the flux, which will create the necessary atmosphere for the solder to melt. You can use the standard tin-lead version for such work, since ordinary copper will have to be soldered. Rosin can act as a flux, or acid can also be used. It all depends on what a person has in the house.
Back to the table of contents
Continuation of the workflow
Next comes the service itself, everything must be done very carefully. A thin layer of molten metal is applied to the conductors. Moreover, all four wires that are to be connected are subjected to this procedure. Now you can safely connect all the conductors together. To do this, they are pressed against each other, and then they are warmed up using the same soldering iron.
To connect, it is sometimes enough to hold the heated device on the wires for a few seconds. Now you need to check the strength of the connection. To do this, it is worth pulling the soldered wires. If the soldering is good, they will be firmly attached to each other. At this point, the process can be considered complete.
Of course, you should not immediately plug the connector into USB, because there is a high probability that a short circuit will occur. Be sure to insulate the conductors. For these purposes, in most cases, the most ordinary electrical tape is suitable. It is best to wind it up at once, not in one, but in several layers. This will increase the protection of the device.
Now all that remains is to put the finished fan on the table, then insert the cord into the corresponding connector on the system unit. He'll probably start blowing. In this case, of course, he will not have any adjustment of the rotation speed. For this purpose, additional devices must be included in the chain. For example, you can put a voltage regulator. This device will allow, by changing the resistance, to lower the rotational speed of the cooler.
The regulator is installed in the circuit.
It often looks like a normal mechanical regulator. Of course, you can do without this option.
Throughout the long winter, we look forward to pleasant summer days, and with the onset of the hot season, for some reason, we begin to dream of coolness. How delightful it will help you recuperate and relieve fatigue from the slight breeze created by a small homemade fan. Plus, making it is incredibly fun, right?
We suggest that you familiarize yourself with step-by-step instructions for assembling the simplest effective devices from literally junk starting materials. The article presented to your attention describes in detail how to make a fan with your own hands and what a home craftsman will need for this.
At your disposal is a detailed description of the manufacture of options, the action of which has been tested in practice. You can make such devices with your own hands, without having any experience at all. For a full perception of information, step-by-step photos and video instructions are attached.
The simplest fan can be made from CD disks. It can be used, for example, for local impact on a user who spends a long time at the computer.
We will prepare the source materials for the work:
- CDs - 2 pcs.;
- low-power motor;
- wine bottle cork;
- wire with USB plug;
- a tube or rectangle made of thick cardboard;
- soldering iron;
- candle or lighter, hot glue;
- pencil, ruler, squared paper.
For our purposes, you can use a motor from an old toy, for example, from a typewriter. As a cardboard tube, a sleeve from a roll of toilet paper, slightly refined with decorative finishing paper, is suitable.
The main advantage of this model is that all the materials that are necessary for its manufacture can be found in almost any amateur to do everything with his own hands.
The mini fan assembly process is pretty simple.
Take one of the CDs and use a marker to divide its surface into eight identical sections. The easiest way to do this is to use a piece of squared paper.
Let's draw a cross on it from a horizontal and a vertical line. Divide each of the four resulting right angles in half. Using the cells, this is not difficult at all.
Using a very simple method using a checkered leaflet, we can achieve an ideal disk layout into eight equal sectors
We put a disk on our drawing so that the intersecting lines are in the very center of its hole. By alternately applying a ruler to the lines diverging from the center, we make markings on the disc. This will make the sections the same.
To divide the disc into blades, draw along the marking lines with a soldering iron from the transparent part to the edge.
Scissors can also be used for cutting, but there is a danger that the workpiece will crack during operation. If there is no soldering iron, you need to use a knife previously heated on the stove. When working with a soldering iron, a fused plastic is formed along the edges of the cut, which can be easily removed with a knife.
Cutting the disc with a soldering iron is the most effective method in which the workpiece does not crack or deform, and the remains of the deposited plastic can be easily removed with a knife
We heat the disk surface over the flame of a burning candle so that the blades can be slightly turned. If you don't have a candle, a lighter or blow dryer will do.
The central part of the disc should be heated, and all blades should be turned in the same direction. A wine stopper is placed in the opening of the disc. To better fix it, you need to pre-process the edges of the hole with hot glue.
The USB cable must be connected to the motor. If we do not guess with the direction of rotation of the propeller, it will be possible to swap the reins, that is, to change the polarity.
The motor must be glued to the cardboard tube, and the tube itself must be glued to the second CD, which will act as the base of the stand.
When the plug is installed in the hole, the stand from the second CD and cardboard tube, as well as the connecting device are already assembled, it is very important to correctly fit the propeller onto the motor shaft
Now the propeller must be "put" on the rod of the future fan. We will try to make sure that it is installed strictly in the center. You can fix it in this position with hot glue.
After completing all the work, the fan is ready for use.
Although the construction of this device will not take you much time, the result of the work performed will undoubtedly please you
How to make a similar, but slightly more complex design, including a regulator in the circuit, look at the video posted at the end of this article.
Do you find this DIY instruction manual complicated? Then you may be interested in information about and the rules for their selection in order to purchase a ready-made device offered by manufacturers of household appliances.
Plastic bottle fan
What our craftsmen do not make from plastic bottles! It's time to say that the fan from them is also very good. Perhaps he will not ventilate your entire room, but he will definitely help someone who is forced to work at a computer.
We offer two options for creating such a fan model.
Option # 1 - hard plastic model
To get the job done, we need:
- a plastic bottle with a capacity of 1.5 liters;
- motor from an old toy;
- small switch;
- battery "Duracell";
- marker;
- scissors;
- candle;
- hammer and nail;
- styrofoam;
- hot glue gun.
So, we take an ordinary 1.5 liter plastic bottle with a cork. Cut off its upper part at the level of the label line. It is she who is what we need to make the propeller. We divide the surface of the plastic blank into six parts.
We try to mark it up so that we get equal sectors: the quality of the future device depends on it.
We cut the workpiece along the markings almost to the neck. We bend the blades of the future propeller and cut off every second of them. We are left with a blank with three blades equidistant from each other. The edges of each of the blades must be rounded off. We do it carefully.
To remove those parts of the blades that are closer to the neck of the workpiece, it is better to use a household knife; don't forget to round the edges of the blades
Now we need a small candle. We light it up. We heat each blade on it at the base in order to turn it in the direction we need. All blades must be turned in the same direction. We remove the cover from the workpiece and punch a hole in its very center with a nail and a hammer.
We put the plug on the stem of a small motor. Such motors can be left over from old children's toys. As a rule, getting them is not difficult. We fix the cork with glue.
Now you need to make a base on which the motor will hold. For this purpose, we take, for example, a piece of Styrofoam. We fix a rectangle on it, which can also be cut out of foam packaging.
On the upper surface of this rectangle our motor will be fixed, to which the propeller is attached. To do this, a recess must be made in the foam, corresponding to the parameters of the motor.
Hot melt glue is used to fix the elements of the product. In its absence, other adhesives can be used. It is important that the mount itself is as reliable as possible.
The question is trivial. First, we recommend that you determine the location of the homemade fan. Two types of motors dominate in technology: collector (historically the first), asynchronous (invented by Nikola Tesla). The first are very noisy, switching sections causes a spark, brushes rub, causing noise. A squirrel cage induction motor is quieter and generates less noise. You will find the start-up relay in the refrigerator. By adding a couple of joke phrases, let's return the seriousness of the site. How to make a fan with your own hands, do not scare your family. Let's try to answer.
Aspects of designing a homemade fan
The fan device is so simple, it makes no sense to tell, paint the insides. What to consider when designing? Remember the growl of the cyclone vacuum cleaner, the volume is over 70dB. There is a collector motor inside. More often devoid of the ability to regulate speed. Decide whether a similar sound pressure level is acceptable at the installation site of a homemade fan? Having chosen the latter, we will concentrate on induction motors, simple models do not require a starting winding. The power is low, the secondary EMF is induced by the stator field.
The drum of an asynchronous motor with a squirrel-cage rotor is cut with copper conductors along a generatrix, kind of an angle to the axis. The direction of the slope determines the direction of rotation of the motor rotor. The copper conductors are not insulated from the drum material, the conductivity of the Olympic metal is superior to the surrounding material (silumin), and the potential difference between adjacent conductors is small. The current flows through the copper. There is no contact between the stator and the rotor, the spark has nowhere to come from (the wire is covered with varnish insulation).
The noise of an induction motor is determined by two factors:
- Coaxiality of stator and rotor.
- Bearing quality.
Correctly carrying out the adjustment, maintenance of the induction motor, you can achieve almost complete noiselessness. We recommend that you consider whether the sound pressure level is important. It concerns a duct fan - it is allowed to use a collector motor, the requirements will be set by the location of the section.
The duct fan is placed inside the duct section, mounted, breaking the duct. The section is removed for service.
Noise is losing its dominant role. The sound wave, passing through the air duct, is attenuated. Part of the spectrum with inconsistent dimensions relative to the width / length of the section of the path is especially fast. Read the tutorials on acoustic lines for more details. The brushed motor can be used in basement, garage, deprived of people. The neighbors of the cooperative will hear, rather they are too lazy to pay attention.
What is good about the collector motor, what we are fighting for the right to use. Three disadvantages of asynchronous:
At the initial moment, the asynchronous motor does not develop a large torque; a number of special design measures are taken. It doesn't matter for the fan. Most household models are equipped with asynchronous motors. In production, the number of phases is increased to three.
Search fan motor
One YouTube video suggested using a 3 volt DC motor from a hardware store. Topping the USB cable, works by rotating the blade of the laser disk. A useful invention? If you are tired of an extra port, it will help you to survive the heat. It's easier to take a processor cooler, power it from the system unit. There is a yellow wire for 12 volts (red for 5). The black pair is the earth. Assemble from your old computer. Citizens of the Russian Federation are simply too lazy to invent, we throw curious equipment into a landfill.
Asynchronous fan motors operate without a starting capacitor ... The peculiarity of fan motors is: they go directly with the winding. A couple of tips to help you get your hands on the engine:
Make a fan impeller
The question of what to make a fan is not resolved, the authors keep silent about the impeller. First things first, the refrigerator! The compressor is blown by the impeller. You will get the motor, remove it. It will come in handy. As for the washing machine, put the drum on the aircraft propeller. A plastic tank is good for making a body. Warm the folds with a construction hairdryer.
Examine the blender, supply an unnecessary impeller-shaped laser disc. You can make a fan yourself using the materials at hand. It doesn't require a lot of power, it makes no sense to overdo it, honing the details. We believe readers know how to make a fan with their own hands.
Perpetual fan from cpu cooler
We decided to please the readers by telling us how to make a fan. The review is far from the first, I had to dig, looking for something worthwhile. The idea of \u200b\u200bcreating an eternal fan that spins forever looks gorgeous. The user mail.ru posted a design that looks attractive. Let's take a closer look as we figure out how to make a fan that runs forever.
You know, of course, system units work quietly (modern models). The slightest noise means: the cooler has lost its axis, or it's time to lubricate the aging fan. They work for hours, days add up to weeks, the system unit will last for years. Made possible thanks to sophisticated technology. Think, noise depends on the magnitude of the friction force. Mechanical energy becomes thermal, acoustic due to the presence of roughness. CPU coolers rotate easily, it's worth blowing up.
The author of the video - we apologize for the lack of a name, we justify: the video is in English - offers to assemble an eternal fan from an accessory. The precision of fit of the parts is great, the blade turns easily. Costs are reduced to a minimum. The author of the video posted by the deirones channel noticed that the processor fan is powered by direct current. Climbing inside, I found four coils equally spaced around the circumference, with their axes directed to the center of the device.
There are no switches inside, which means a paradoxical fact: the field of the coils is constant.
If the induction motor of a typical fan is powered by an alternating voltage of 220 volts, which creates a rotating magnetic field, in our case the picture is constant. You could say: inside the rotor drives the commutator, which creates the desired distribution. Not true, confirmed by the further train of thought of the author, the result of experience. A Western innovator decides to replace the coil with a permanent magnet. Indeed, there is no alternating field - why electric current?
Demonstratively, the author cuts off the power wire, places neodymium (hard disk) magnets with the perimeter of the frame. Each on an extension of the coil axis. The work was finished, the blades began to revolve briskly. We believe that the principle is simply used, which is hushed up by orthodox literature. Trade secret of the patentee.
The initial motion of the blade is obtained by random air fluctuations. It resembles a magnetron, the buildup of oscillations is caused by the natural chaotic movement of elementary particles. The question arose what sets the direction of rotation. The design is absolutely symmetrical. We decided to figure it out, we express our observations:
Agree, it is more convenient than to muddy USB ports, to constantly waste batteries. A perpetual fan works from an arbitrary position, devoid of wires. We believe that the strength of the magnets plays a decisive role. The simple rule stops working: more is better. The golden mean is slipping. When the blades spin from a random air stream, overcoming the field of neodymium pieces. Weak magnets are probably powerless to maintain steady rotation. The field strength should be exactly the same as that generated by the coils under +5 or +12 volts.
Create a perpetual fan correctly
We discussed how to make a fan, measure the direction and strength of the magnetic field of the coils. They use special devices. Magnetometer, teslameter, formed by a magnetic induction transducer, a measuring module. When the fields interact, the resulting picture is obtained, called cohesion. The converter generates EMF. Size determines the measured strength of the magnetic field. Like two fingers! It costs 10,000 rubles.
The magnets will be located at a significant distance from the axis. The coils are much closer. You need to know how the picture changes with distance. According to Coulomb's law, the force falls in inverse proportion to the square of the distance, which is true for single charges of arbitrary sign. Separate magnetic poles in nature have not yet been found (it is not possible to create), the distance cube is introduced into the law. Let's say that the distance to the coil from the axis is 1 cm, the perimeter along the diagonal is 10. This means that neodymium should be 10 x 10 x 10 \u003d 1000 times stronger than a small coil.
Nobody obliges to place neodymium magnets on the diagonals of the fan perimeter. The poles are criss-cross. They regulate the strength of the impact over a wide range. Placing neodymium magnets in the center of the sides of the fan frame significantly increases the field strength. Let's make the calculation. Let's say the hypotenuse of a 10 cm side triangle is the diagonal. The distance to the center of the square will be 10 / √2 \u003d 7 cm. You see, the ratio falls from 1000, reaching 7 x 7 x 7 \u003d 343. Vesomo, desperate to find strong neodymium magnets to create an eternal fan.
Force is measurable! A compass is good (there are custom designs that can be assembled by hand, for example, http://polyus.clan.su/index/indikatory_magnitnogo_polja_svoimi_rukami/0-52). One coil should be connected to the power supply. Then find the position, the raised arrow will deviate by about 45 degrees (if you don't like it, take any other azimuth). Then start the experiment with neodymium. Place the piece at different distances, making sure that the deflection of the arrow coincides with that obtained when using the processor fan coil. Surely the distance is not equal to the diagonal, half of the side, you will have to break, cut, neodymium.
Sawing one edge along the length, carefully break the parts against the nail, obtaining the required field strength to create an eternal fan. We assume that the induction is distributed in proportion to the volume. Today they told you clearly how to make a fan with your own hands!
Power supply
Anyone who wants to make a fan with his own hands sees 3 problems: getting the engine, power, making a propeller. The details must fit together. Three problems solved, start making a fan with your own hands. Today there is an abundance of switching power supplies at home. Think about it, it started in the 90s. Game consoles, mobile phones, other equipment. The technique breaks down, switching power supplies remain. The voltage is sometimes non-standard, most motors work, powered by any voltage. It's just that the speed will change according to the voltage. Broken household appliances are lying around at home - immediately make a fan yourself.
Homemade fan power supplies
People are constantly trying to make a special fan with their own hands. One issue is more often outside the scope of discussion: power supply. The fan design itself is so obvious, it makes no sense to dwell in more detail. So, of course, there is an incredible amount of batteries today. Will they be able to work for a long time. The answer is no. In extreme cases, take the "crown", in Soviet times was considered a reliable source of energy. The power supply is bad, the power will gradually decrease, the speed will decrease, and the person will be annoyed. Stability without additional effort is important. There is no small 12 volt battery - get ready: let's start looking for how to make a power source for a homemade fan.
The first thing that comes to mind is to use the computer. It is known that miniature devices are powered by a USB port. Gadgets are recharging. The USB port is a source of inexhaustible energy. The voltage is low, a low voltage DC motor is needed. We suppose you can find it at home, buy it at a hardware store. How much is the port power: 2–3 W according to old standards. Another thing is to find a host device with an updated version of the interface (2014 was recognized as a rarity). The developers promised to give out 50 watts (even more, it's hard to believe). True, there will be more wires, the nominal voltages will increase. We remind you, according to tradition, power is supplied to the red (+), black (-) wires. White, green - signal.
It is clear that it is difficult to expect high power - even if the port supports it, the motor will not pull. It is recommended to look at a higher voltage. The motor must be supplied with a higher voltage. For example, a CPU cooler is recommended. The supply voltage is less than the prescribed 12 volts, the rotation speed will simply decrease. Excess beware - motor may burn out.
We are looking for energy, the issue is easier to solve than for 3 volts:
12 volt power supply for a homemade fan with your own hands
We suggest not to assemble a switching power supply, to do it yourself with your own hands. Recall that the former are distinguished by small transformers. Consequently, the power supply unit will be relatively large. It will consist of the following parts:
- A step-down transformer. We do not name the number of turns in advance, the voltage is unknown, by rectifying it with diodes, we get 12 volts. Of course, you can experiment, like a YouTube video about homemade radios, capturing the reader and looking for a ready-made solution.
- A full-wave bridge, adding three diodes to one, increase the efficiency. The radio components are not very expensive.
- The backbone of the power supply is ready for a homemade fan to serve for a long time, let's straighten the network ripple. After the bridge, turn on the low-pass filter, redraw the circuit from the Internet.
The output is a constant voltage with an amplitude of 12 volts. Try not to mix up the terminals. Where the plus, where the minus comes out, you can understand by studying the diagram. Below is a drawing of the bridge, see, read the explanations. In electronics, the direction of the current is indicated opposite to the true one. The charges flow, according to popular belief, in the direction from plus to minus (towards the electrons). Reading the diagram, you will see: at the diode, transistor, the emitter marked with an arrow looks wrong. In the direction of movement of positive charges. Each has marks, on the diagram it is indicated by a huge arrow-triangle. Therefore, we always recognize the "plus", guided by the graphic designations given in the drawing.
The figure shows: the plus will be on the right, transmitted according to the arrow of the diode to the lower output terminal. The minus will go up. With an alternating voltage (roughly speaking), plus, minus will alternate from left to right, the name of the rectifier will become clear - full-wave. Works on the positive part of the voltage and negative. Take power diodes, low-frequency ones. Solid size, power dissipation is relatively high. You can calculate using a simple formula taken from a physics course. The resistance of the open p-n-junction (leafing through the directory) is multiplied by the current consumed by the motor, we take the margin at least 2 times. The motor case contains an inscription indicating the power, it can be divided by a voltage of 12 volts, simply multiplied by 2 - 3, take a diode with an equivalent dissipation power (see the reference book).
Now we will calculate the transformer ... We went here http://radiolodka.ru/programmy/radiolyubitelskie/kalkulyatory-radiolyubitelya/, chose the Trans50 program, we will master it. Note that among the software there is one that allows you to calculate the filter parameters. Do you regret that you are going to make a fan with your own hands? They offer to choose one of 5 windings. Steel is involved everywhere. You can do without, the losses will be great. Steel forms a magnetic circuit, energy goes to the secondary winding. Better to find an old rusty transformer. The times are bad, in the hungry 90s landfills are littered with sheets of scraped windings. There were no problems with winding transformers.
It's time to understand what voltage is required for the correct operation of the circuit. A term borrowed from electronics, AC voltage, will help. The voltage across the active resistance creates a thermal effect equal to the constant voltage of the effective amplitude. To obtain the required voltage value on the secondary winding, you need to divide 12 volts by 0.707 (unit divided by the square root of 2). The authors got 17 volts. An engineering calculation is guilty of an error of 30%, we take a small margin (part of the amplitude up to 1 volt will be lost on diodes).
As for the secondary winding current (calculation required), type something like "cooler power" in the search engine. Let's do it together with the readers. Smart articles write: the current consumption of the cooler is indicated on the case. The required parameter will be substituted into the calculator. The author took the voltage of the secondary winding 19 volts. The voltage drop across pn junctions of powerful silicon diodes is 0.5 - 0.7 volts. Therefore, an adequate supply is needed. Smart heads looked for it, concluded that the processor cooler does not consume more than 5 W, therefore, the current is 5 divided by 12 \u003d 0.417 A. Substitute the numbers to the downloaded calculator, for the ribbon core we get the transformer design parameters:
- Cross-sections of the magnetic core for winding 25 x 32 mm.
- Window in the magnetic circuit 25 x 40 mm.
- The magnetic core is finished with a frame for winding a wire with a thickness of 1 mm and a section of 27 x 34 mm.
- The wire is wound along the larger side of the window, 1 mm from the edges remains a margin, a total of 38 mm.
The primary winding is formed by 1032 turns with a diameter of 0.43 mm. The approximate length of the wire is 142 meters, the total resistance is 17.15 ohms. The secondary winding consists of 105 turns of a copper conductor with lacquered insulation 0.6 mm in diameter (length 16.5 meters, resistance 1 Ohm). Now readers understand: the question of what to make a fan is started to be solved with a core ...
How effective are the proposed technical solutions? The fans are known to Ancient Egypt. Michael Jackson's clip recommending “Remember the time” testifies. The plot was hardly made without the advice of archaeologists and historians. We would like to report that in Mexico, most ladies use fans. The Spaniards know how to deal with the heat, the country lies on the equator. Think ...