You can make a low-noise fan for room air conditioners, for window and table fans, for cooling or heating various equipment.
In front of you general view low-noise TsAGI fan (see Fig. 1). It consists of an electric motor, a housing and an impeller (impeller). The fan can be made without a housing. But then it will not produce such a powerful air flow. The fan diameter can be up to 400 mm.
If you have an electric motor and you know its maximum speed, then from the graph (Fig. 2) it is not difficult for you to determine what maximum diameter you can make a fan.
So, you have decided to make a fan. Keep in mind that the noise of the entire installation consists of the noise of the electric motor and the impeller. So if you want to get low noise fan, then choose a low-noise electric motor.
The fan impeller is made of metal, duralumin or steel sheet. The thickness of the sheet is selected depending on the diameter of the impeller within 0.5-2 mm. The larger the diameter of the impeller, the thicker the sheet should be taken.
First, unroll the impeller. The dimensions of this scan are shown in Figure 3. Here the numbers do not indicate millimeters, but fractions of the radius of the impeller blade. To obtain dimensions in millimeters, multiply the indicated numbers by the selected radius of the fan impeller. Then give the impeller blades the desired profile - knock them out on a blank. Make a blank from hard wood according to the dimensions indicated in Figure 4. Here the dimensions are also given in fractions of the impeller radius.
How to get such a blank? It is processed using three curved patterns. These templates are made from flat templates (Fig. 5). You will find the bending radii of bent templates and the dimensions of flat templates in the table. Bent templates the correct manufacturing of the blank is checked using three sections I-I, II-II, III-III. Align the ends of the template arc with the corresponding vertical marks on the sides of the blank. Make sure that the axial marks on the templates and blank are located in the same plane. Templates are easiest to make from tin. But any metal or plastic sheet will do, only the working edge of the templates should be made no thicker than 0.5 mm.
The working surface of the blank must be smooth and smooth. To do this, it must be thoroughly cycled and sanded. Only after this can the blades of the fan impeller be knocked out on it. To prevent the impeller blank from moving when hammering out, nail it in the center to the blank. And to increase the rigidity of the blades, after knocking them out at the root of the blade along the axis, make small indentations - ridges.
The bushing for mounting the impeller on the axis of the electric motor is machined to lathe, or done manually as shown in Figure 6. The impeller and bushing are connected with rivets or screws.
When impeller fan will be assembled, be sure to balance it statically.
We have already said above that the fan can be made with or without a housing. Figure 1 shows one of the possible options structures with a body. Other designs are also possible.
The weather is getting warmer outside, it's time to think about ventilation. In this episode Roman Ursu will do bladeless fan. You can easily repeat this product with your own hands. Four pieces of cardboard are used in the product. The width must match the width of the cooler. 120 mm. A switch and power connector are built into the housing. Let's take measurements and required diameter let's make a hole. You will also need a 12-volt power supply for a cooler that consumes 0.25 m. The unit is 2 amperes, so that’s enough. The top of the Dyson fan is cylindrical in shape. This means that we draw two circles with a diameter of 15 cm. One of them is 11 cm, the other is 12 cm. To ensure that the parts stick well to the base, we take one of the walls, apply the parts, draw a line and cut them off. Now, to form the cylinders, you will need three segments with the following dimensions: 12 x 74, 12 x 82, 15 x 86 cm. We will figure out what and where to glue at the assembly stage. Let's make cuts in each wall. These will be the air channels. They look like nice legs.
Let's start assembling a beautiful bladeless fan, placing the courier in the middle. We glue each wall one by one. The wires can be removed as shown in the video. It would be nice to figure out the connection. We use a switch, so we separate one of the wires and form a circuit. The wires go to the power connector, black to minus, red to plus.
You need to connect all the previously prepared parts with your own hands. Take the ring from internal diameter 11 cm. She will be in front. And the segment is 12x74. We connect as in the video.
We repeat the same with the second ring and the 12 x 82 blank. To keep the rings fixed and stable, we use five small strength partitions. The length is just under 12 cm. All that remains is to close the structure.
We use the last piece of 15 x 86 cm.
Finally, we make it beautiful, remove excess glue, and cover it with paint. In general, the bladeless fan is ready.
There's a lot ahead useful homemade products, we are waiting for the warm sun to take pictures next video and show it on the channel.
Comments:
Installing a fan is a sensitive issue. Before making a fan with your own hands, you need to determine its installation location. The fact is that in the manufacture of structures today two types of engines are used:
- collector;
- asynchronous.
During operation, collector units emit a lot of noise, and when it switches, a spark occurs. In addition, the movement of the brushes also makes a lot of noise.
Asynchronous motors, which are equipped with a squirrel-cage rotor, are the complete opposite. At self-production For fans, you can use an element from the refrigerator as a starting relay.
Fan Manufacturing Principles
When making a fan yourself, you need to take into account some aspects, the most important of which is noise. To get an idea of the work commutator motor, you just need to remember how the Cyclone vacuum cleaner works, its volume is about 70 dB. Based on this, you should consider whether to use such an engine or not. In this regard, it is most realistic to use an asynchronous motor; moreover, when performing the simplest fan model, a fan is not required starting winding. And its power is small, and the secondary EMF is induced by the field from the stator.
The drum in an asynchronous motor has a squirrel-cage rotor with cut copper conductors along the generatrix, passing at an angle relative to the axis. It is this slope that determines the direction of rotation of the rotor in the engine. The copper conductors are not insulated from the drum material, since they have a conductivity that is superior to the surrounding material, and the potential difference between adjacent conductors is small. And due to this, a current flows through the copper. The stator and rotor are not connected to each other by contacts, and therefore no spark occurs, since the wire is covered with varnish insulation. That's why the noise asynchronous motor determined by the following factors:
- ratio of stator and rotor;
- quality of bearing elements.
At correct setting With an asynchronous motor, silent operation of the motor can be achieved. Well, if we are talking about how to properly make a duct fan with your own hands, then you can allow the installation of a commutator motor, but taking into account where the section will be located.
The duct fan is installed in the air duct section itself and is located in the center of the duct. For this reason, when a fan is made in an air duct, noise does not play a special role, since the sound wave attenuates while it passes through the duct.
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To make a fan yourself, you need to purchase a model of a kitchen or bathroom fan, the one that is mounted to the hood. The box from under it will also come in handy, and you will also need:
- scissors;
- net;
- glue or tape.
Fan installation diagram.
The structure will be powered from the network, but will consume little electricity. To begin with, take a box and make a through hole in it. The design of the fan for hoods is cylindrical in shape, and it will also be the basis for the shape of the hole.
Subsequently, a fan will be installed in this hole. The hole is cut with a smaller diameter than the structure itself in order to make it more stable and safe. An opening is made on the side of the bottom of the box to allow the cord to exit. To prevent the fan from dangling in the box, you can place cardboard scraps in it and secure it with electrical tape. For safety, a protective mesh is installed on the front part where the blades are located. The denser the mesh in the mesh, the less likely it is to get caught by the blades. Making a homemade fan does not require much expense, and if you decorate the box, you can get additional element interior arrangement.
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USB fans: features
Such a model will not be easy to make. This great option for individual cooling when working at a computer. Such a device is obtained with sufficient power, and the energy consumption is not much more. To construct this design you will need:
- a couple of CDs for the computer;
- cord with USB plug;
- wires;
- an old motor, the kind usually installed on children's toys;
- wine stopper;
- cylindrical cardboard;
- glue and scissors.
First of all, the disk is cut into blades. The power of the air flow depends on the presence of blades; the more there are, the stronger the blowing will be, but the segments themselves should not be small.
Only one disc is cut, the second will be used as a stand.
To bend the blades, they are heated over a small flame and bent forward at an angle.
They should be turned in one direction. When the disk with blades is ready, a plug is inserted into its center and a hole is made in it.
In order to make the wire usable, the outer winding is removed from one end of the USB cord, under which there are 4 wires. The paired ones can be separated, connected to the motor and insulated.
So, all you need to prepare is sharp knife, electrical tape, an unnecessary USB cord 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. Next we will look at two instructions that will clearly explain how to do USB fan at home with your own hands!
Idea No. 1 – Use a cooler
As a rule, it will take no more than 15 minutes to assemble a USB fan from a cooler. First you need to prepare the cooler. There are two wires coming out of the device - black and red. Strip the insulation to 10 mm and set the prepared element aside.
Next you need to prepare the USB cable. Cut off one half of it and peel off the insulation at the cut point. Under it you will see four contacts, of which two are necessary: red and black. You also clean them, but it’s better to trim the other two (usually green and white) so that they don’t get in the way. 
Now, as you understand, you need to connect the prepared contacts in pairs, according to: red to red, black to black. After this, you need to carefully insulate the cable connections and make a stand. As for the stand, it’s a matter of your imagination. Some successfully use wire, some very interestingly cut out a seat in a cardboard box.
In the end, the homemade mini fan is connected to the computer, and you can enjoy the operation of your own electrical appliance.
Cooler idea
Idea No. 2 – Use a motor
In order to make a USB fan from a motor and a CD, it will take a little more time, but you can still easily make such an electrical device with your own hands in an hour. 
First, we prepare all the elements of the device. In this case, you will also need an impeller (blades). 
To make the impeller, we recommend using an ordinary CD. Draw it into 8 equal parts and carefully cut towards the center. Next, heat the disk (you can use a lighter), and when the plastic becomes more elastic, bend the blades (as shown in the photo).
If the impeller is not bent, while the disk rotates air flow will not be created. Here you need to use moderation so as not to overdo it.
When the blades are ready, move on to creating the main mechanism. We recommend inserting it inside the disk plastic stopper, in which you need to make a hole for the motor barrel. Carefully fix the core and move on to creating a USB fan support for the laptop. 
Here, as in the previous version, everything depends on your imagination. Of all the available means, the option with wire is the most suitable. When homemade USB the fan is ready, we connect the motor wires to the cord wires, carefully insulate the twist and proceed to test work.
Visual video instructions:
Disk idea
CD idea #2
As you can see, in order to make a fan from a cooler or a motor from a machine, it does not require much time and skills in working with electrical appliances. Even a beginner can cope with this task!
Summer has arrived, which means heat, heat and an eternal lack of coolness. But this problem can be fixed, and quite easily. You just need a few details and a little free time to make your life easier with your own hands, to fill it with the light coolness that you will certainly get by making a USB fan at home. Of course, you can go and buy a fan in a store, but how nice it will be to sit next to the same computer, and a light breeze from the USB fan you created will blow on you. And a thing created with your own hands always pleases not only the eye, but also develops self-love.
We invite you to watch a video of a homemade USB fan:
Tools for usb fan:
- A regular CD (not necessarily new);
- The tube of silicone glue is empty;
- Wooden block;
- Mini disk;
- USB cord;
- Motor;
- Holder;
- Adapter;
- Silicone glue gun.
You need to make three holes in the tube, one in the lid and two on the sides. Holes can be easily made using a regular nail, which must first be heated.
IN wooden block it is also necessary to make a slot or recess. This can be easily done using sandpaper.
The mini disk easily turns into a propeller. To do this, you need to draw it into uniform blades, then heat a stationery knife and cut along pre-drawn lines. And after that, we heat the base of each blade with a lighter and, using our hands, bend each blade a little to make a propeller.
We take the motor, holder and adapter from a non-working CD drive.
Now let's start assembling the USB fan.
Heat up the glue gun. Lubricate the holder along the axis with silicone glue from a glue gun. The propeller must be firmly seated on this glue. Press on all sides. Then, on the other side of the holder, add a drop of glue and glue the adapter. We wait until the glue dries well. This usually only takes a couple of minutes.
Now take a tube of silicone glue, remove the lid and coat the inside with silicone glue. And we insert the motor inside so that the part that we will connect sticks out of the hole that we originally made.
Then we insert the USB cord into the side hole of the glue tube and connect the ends of the wires to the motor.
You need to pour silicone glue into the recess in the wooden block, and place the wire from the USB cord tightly there, and glue the tube itself with the motor inside to the base of the block. And on the other side of the block we glue the CD with silicone glue.
Now the propeller needs to be placed on the side of the adapter glued to it onto the sharp edge of the motor, which sticks out of the hole in the tube from under the glue.
And finally, our USB fan can be plugged into the network and get that long-awaited coolness.
