Bladeless fan. How to make a fan with your own hands: the best homemade models Visual video instructions

It is very hot in the southern regions; nothing will prevent you from acquiring such a “super-powerful” portable fan.

You can take an 18-volt electric drill motor, an RC airplane propeller, and a laptop battery. 4 volts is the best option, and it’s not too noisy during operation. At 12 volts, the device will be super powerful, loud, and will "rattle" (via vibration) on the table.

Required components
The motor and batteries are the most expensive parts. You can buy a cheap used drill with a bad battery and just use the motor. Used laptop batteries usually have 6 cells and will not work if one cell is dead. You can buy these batteries for next to nothing and take the working cells to make a powerful battery (http://www.instructables.com/id/Free-lithium-Ion-Battery-Pack).

Required parts:

• electric motor direct current electric drills;
• laptop battery;
• plastic fan blades;
• 1/8" plywood;
• plywood and 2x1" blocks for engine mounting;
• switch (in our case, 2P2T switch for 2 speeds); - electrical cable.

Checking the engine and batteries
Secure the motor and fan to something solid.
You can try applying different voltages to it to adjust the desired wind strength. In our case, for a 4-volt battery, the ideal current was 1.5A. An 8-volt battery for good power corresponds to a current of 3A.
Use 4 batteries, 4 parallel 4V and 2 sets of 2 parallel 8V batteries. So at low power they will last about 5 hours, and at high power for approximately 1.5 hours.
Connect the 2P2T wires with a switch to switch between series and parallel circuits.

Creating an air duct and mounting the engine
First, glue the 2x1” pieces together to form a T. Measure the pieces to give the propeller about a half inch of clearance on each side.
After gluing the bars, round their edges to make them streamlined.
To mount the engine, cut 2 triangles out of wood. Soak a piece of 1/8" plywood in water, then bend it and let it dry. You can cut 3 3.5" strips of wood grain perpendicular to the piece to make it easier to bend. Use timbers held together in a T as a base and cover it with 3 pieces of plywood, overlapping the joints and leaving one joint. Then glue the 3 ends of the T to the duct plywood. It is also important to try on the engine mount to make sure there is enough clearance.
Then cut two pieces of 1/4" plywood about 4.5 x 1.5 to form the duct support at the top. Glue these supports to the duct and to the "T".

Glue a piece of wood to the "T" to stop the motor from sliding backwards as the motor pushes the air forward and the motor then pushes back.
To secure the motor from below, you can use 2 zip ties.

Battery layout
Use a 6-cell laptop battery to power the fan. For a bicycle fan in motion, you need a 12V fan. As table fan 4V or 8V is more than enough.

Wires to the motor
Solder two 14 gauge wires to the motor. Insulate with electrical tape. To prevent wires from getting caught in the blades, secure them to the fan support.

Testing
Power the motor in parallel with 2 sets of 3 combined cells. The voltage should be about 11.8 V. Even the multimeter should show 3.38 A. The multimeter has some resistance, so the current is actually about 4A. More than 47 W. This is already a very powerful little fan. At 16 V, this fan can already push a bike decently.

Installation of protection
The propeller rotates too quickly, so protection will need to be installed.
Using wire cutters, cut a circle from the large fan guard so that its radius is about half an inch larger than the duct. Loop the wire around the duct. Then hot glue the protection to the front and back.

Switch installation
Install the switch. The fan can now be turned on and off easily. You can use a 2T2P switch and get two rotation speeds.

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 has cylindrical 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 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 shoot the next video and show it on the channel.

Creating air flow with high density possible in several ways. One of the most effective is a fan. radial type or "snail". It differs from others not only in shape, but also in its operating principle.

Fan device and design

Sometimes an impeller is not enough for air movement and power unit. In conditions of limited space, a special type of exhaust equipment design should be used. It has a spiral-shaped body that acts as an air channel. You can make it yourself or purchase it already finished model.

To form a flow, the design provides a radial Working wheel. It connects to the power unit. The wheel blades have a curved shape and create a discharged area when moving. Air (or gas) enters it from the inlet pipe. When moving along the spiral body, the speed at the outlet increases.

Depending on the application centrifugal fan snail maybe general purpose, heat-resistant or corrosion-resistant. It is also necessary to take into account the amount of air flow created:

• low pressure. Application area - production workshops, Appliances. The air temperature should not exceed +80°C. Mandatory absence of aggressive environments;
• average pressure value. It is part of exhaust equipment for removing or transporting small fraction materials, sawdust, grain;
• high pressure. Forms an air flow into the fuel combustion zone. Installed in many types of boilers.

The direction of movement of the blades is determined by the design, and, in particular, by the location of the outlet pipe. If it is located on the left side, the rotor should rotate clockwise. The number of blades and their curvature are also taken into account.

For powerful models you need to do it yourself solid foundation with housing fixation. The industrial installation will vibrate strongly, which may lead to its gradual destruction.

Self-production

First of all, you need to decide functional purpose centrifugal fan. If it is necessary for ventilation of a certain part of the room or equipment, the housing can be made from scrap materials. To complete the boiler, you will need to use heat-resistant steel or make it from stainless steel sheets yourself.

First, the power is calculated and the set of components is determined. The best option The snail will be dismantled from old equipment - an extractor hood or a vacuum cleaner. The advantage of this manufacturing method is the exact match between the power of the power unit and the body parameters. A snail fan can be easily made with your own hands only for some applied purposes in a small home workshop. In other cases, it is recommended to purchase a ready-made industrial-type model or take an old one from a car.

Procedure to make a centrifugal fan with your own hands.

1. Calculation overall dimensions. If the device will be installed in a confined space, special damper pads are provided to compensate for vibration.
2. Manufacturing of the body. In the absence of finished design You can use plastic sheets, steel or plywood. In the latter case Special attention is given to sealing joints.
3. Installation diagram of the power unit. It rotates the blades, so you need to choose the type of drive. For small designs, a shaft is used to connect the motor gearbox to the rotor. IN powerful installations A belt type drive is used.
4. Fastening elements. If the fan is installed on the outer casing of, for example, a boiler, mounting U-shaped plates are made. With significant power, it will be necessary to make a reliable and massive base.

This general scheme, according to which you can make a functional exhaust centrifugal unit with your own hands. It may change depending on the availability of components. It is important to comply with the housing sealing requirements, as well as ensure reliable protection power unit from possible clogging with dust and debris.

The fan will make a lot of noise during operation. Reducing this will be problematic, since vibration of the housing during the movement of air flows is almost impossible to compensate with your own hands. This is especially true for models made of metal and plastic. Wood can partially reduce background noise, but at the same time it has a short service life.

In the video you can see the process of manufacturing a case from PVC sheets:

Review and comparison of production ready models

Considering radial fan snail, it is necessary to take into account the material of manufacture: cast aluminum body, sheet or stainless steel. A model is selected based on specific needs; consider an example of serial models in a cast case.

Let's make a simple fan.
You will need:
1. 3V motor
2. Section for 2 batteries of 1.5 V each. I bought it from the CHIP and DIP store.
3. Switch.
4. Wire 15 cm.
5. Reels from fishing line or ropes, a jar from Polysorb, a jar of gouache.
6. Impeller from the power supply cooler.
7. Soldering iron.
8. Thermal gun.
9. Self-tapping screws 11 pcs. 2 cm long.

1. Take spools of thread with a diameter of 5 mm and a height of 4.5 cm - from fishing line or cord.
Mark a hole for the switch with a marker and cut it nail scissors hole a little smaller size switch and insert the switch into the reel:

2. Now we form the fan frame: put 3 bobbins together and mark four holes for bolts or screws with a marker on the bottom of the upper bobbins. We burn holes through the edges of two bobbins:

3. Using a lighter, melt and clear the red wire from the section with batteries and attach it to one terminal of the switch, and to the other - the second red wire. To isolate the terminals from contact with each other, fill them with hot glue:

4. We attach the red wire to the plus + of the engine, and the black wire, respectively, to the minus - of the engine:

5. The top can be made from a gouache box: on the lid with a soldering iron we form a hole for the wires and 3 holes for the screws. And on the box itself we cut a hole with nail scissors slightly smaller than the diameter of the engine and place it inside. As in the case of the switch, you can pour hot glue on the outside for reliability.

6. We place the impeller from the cooler on the plug, fill the voids with plasticine or fill it with paraffin, use a screw or an awl to make a hole in the plug, fill it epoxy glue or hot glue, and place it on the engine. If this epoxy resin- leave it to dry for a day and only then turn it on!

The question is trivial. First, we recommend determining where to install your homemade fan. Two types of engines dominate in technology: commutator (historically the first), asynchronous (invented by Nikola Tesla). The first ones make a lot of noise, switching sections causes a spark, the brushes rub, causing noise. An asynchronous motor with a squirrel-cage rotor is quieter and generates less interference. You will find the start-up protection relay in the refrigerator. By adding a couple of phrases of humorous phrases, we will return the seriousness of the site. How to make a fan with your own hands without scaring your family. Let's try to answer.

Aspects of designing a homemade fan

The design of the fan is so simple that there is no point in telling or describing the insides. What to consider when designing? Remember the growl cyclonic vacuum cleaner, volume above 70 dB. Inside is a commutator motor. Often deprived of the ability to regulate speed. Decide, is a similar sound pressure level acceptable at the installation site of a homemade fan? Having chosen the second, we will concentrate on asynchronous 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 the generatrix, at an angle to the axis. The direction of the slope determines the direction of rotation of the engine rotor. Copper conductors are not insulated from the drum material, the conductivity of the Olympic metal exceeds the surrounding material (silumin), the potential difference between adjacent conductors is small. Current flows through copper. There is no contact between the stator and rotor, the spark has nowhere to come from (the wire is covered with varnish insulation).

The noise of an asynchronous motor is determined by two factors:

1. Alignment of stator and rotor.
2. Bearing quality.

By properly setting up and servicing an asynchronous motor, you can achieve almost complete noiselessness. We recommend considering whether sound pressure level is important. The case concerns a duct fan - it is allowed to use a commutator motor, the requirements will be determined by the location of the section.

The duct fan is placed inside the air duct section and mounted, breaking the duct. The section is removed for maintenance.

Noise loses its dominant role. The sound wave, passing through the air duct, attenuates. Particularly fast is the part of the spectrum that has inconsistent dimensions relative to the width/length of the path section. Read more textbooks on acoustic lines. The brushed motor can be used in a basement, garage, or unoccupied areas. The neighbors of the cooperative will hear, but will rather be too lazy to pay attention.

What is good about a commutator engine, what are we fighting for the right to use. Three disadvantages of asynchronous:

At the initial moment asynchronous motor does not develop high 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.

Finding a motor for a fan

One YouTube video suggested using a 3 volt DC motor from a hardware store. Tops a USB cord, works by rotating the laser disc blade. Useful invention? If you're tired of the extra port, this will help you survive the heat. It’s easier to take a processor cooler and power it from the system unit. The yellow wire goes to 12 volts (red to 5). The black pair is earth. You can assemble it from an old computer. Citizens of the Russian Federation are simply too lazy to invent, so we throw interesting equipment into a landfill.

Asynchronous fan motors operate without a starting capacitor... The peculiarity of fan motors is that they come directly with a winding. A couple of tips to help you get an engine:

Make a fan impeller

The question of what to make a fan from has not been resolved; the authors kept silent about the impeller. First things first, the refrigerator! The compressor is blown by an impeller. When you get the motor out, remove it. It will come in handy. Concerning washing machine, launch the drum onto an aircraft propeller. Plastic tank It's good to make a body. Heat the bend areas with a hair dryer.

Inspect the blender and equip it with an unnecessary laser disk shaped like an impeller. You can make a fan yourself using available materials. Not required high power, there is no point in trying too hard to hone in on the details. We believe that readers know how to make a fan with their own hands.

Eternal CPU cooler fan

We decided to please our readers by telling you how to make a fan. This is not the first review, I had to dig around to find something worthwhile. Looks great idea to create eternal fan, spinning forever. User mail.ru posted a design that looks attractive. Let's take a closer look, while thinking about how to make a fan that runs forever.

You know, of course, system units work quietly ( modern models). The slightest noise means: the cooler's axis is out of alignment, or it's time to lubricate the old fan. They work for hours, days add up to weeks, the system unit will last for years. It became possible thanks to well-thought-out technology. Think about it, noise depends on the magnitude of the friction force. Mechanical energy becomes thermal and acoustic due to the presence of roughness. CPU coolers rotate easily, just blow on them.

The author of the video - we apologize for the lack of a name, we justify: the video is in English - suggests assembling an eternal fan from an accessory. The fitting accuracy of the parts is high, the blade rotates easily. Costs are reduced to a minimum. The author of the video posted by the deirones channel noticed: the processor fan is powered by direct current. I climbed inside and found four coils, equally spaced around the circumference, with their axes directed towards the center of the device.

There are no commutators inside, which means a paradoxical fact: the field of the coils is constant.

If the induction motor of a typical fan is powered by 220 volts alternating voltage, which creates a rotating magnetic field, in our case the picture is constant. You could say: inside the rotor sets in motion a commutator that creates the desired distribution. This is not true, and is confirmed by the author’s further train of thought and 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?

The author demonstratively cuts off the power cord and places neodymium magnets ( hard drive) frame perimeter. Each is on the continuation of the coil axis. The work is completed, the blades begin to rotate vigorously. We believe that a principle is simply used that is hushed up in orthodox literature. Trade secret of the patent holder.

The initial movement of the blade is obtained by random air fluctuations. Reminiscent of a magnetron, the vibrations are caused by the natural chaotic movement of elementary particles. The question arose as to what determines the direction of rotation. The design is absolutely symmetrical. We decided to look into it and express our observations:

Agree, it’s more convenient than messing up USB ports and constantly wasting batteries. The eternal fan operates from an arbitrary position and is devoid of wires. We believe that the strength of the magnets plays a decisive role. The simple rule no longer works: more is better. A golden mean is emerging. When the blades spin from a random air flow, overcoming a field of neodymium pieces. Weak magnets are probably powerless to maintain stable rotation. The field strength must be exactly that created by the coils under the influence of +5 or +12 volts.

Correctly create an eternal fan

We discussed how to make a fan, measure the direction, force magnetic field coils They use special devices. A magnetometer, Teslameter, is formed by a magnetic induction converter, a measuring module. When fields interact, the resulting pattern is called coupling. The converter generates EMF. The size is determined by the measured strength of the magnetic field. Like two fingers! Costs 10,000 rubles.

The magnets will be located at a considerable 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 decreases in inverse proportion to the square of the distance, which is true for single charges of arbitrary sign. Separate magnetic poles have not yet been found in nature (it is not possible to create them); the cube of distance is included in the law. Let's say the distance to the coil from the axis is 1 cm, the diagonal perimeter is 10. This means that neodymium should be 10 x 10 x 10 = 1000 times stronger than a small coil.

Nobody obliges to place neodymium magnets around the fan perimeter on diagonals. The poles lie crosswise. Adjust the force of influence over a wide range. By placing neodymium magnets in the center of the sides of the fan frame, we significantly increase the field strength. Let's do the calculation. Let's say the hypotenuse of a triangle with a side of 10 cm is a diagonal. The distance to the center of the square will be equal to 10 / √2 = 7 cm. You see, the ratio drops from 1000, reaching 7 x 7 x 7 = 343. We are desperate to find strong neodymium magnets to create an eternal fan.

Let's measure the strength! A compass is suitable (there are custom designs that you can assemble yourself, 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 arrow brought up will deviate by about 45 degrees (if you don’t like it, take any other azimuth). Then start experimenting with neodymium. Place the piece on different removals, ensuring that the arrow deflection coincides with that obtained when using the processor fan coil. Surely the distance is not equal to the diagonal, half the side, the neodymium will have to be broken and cut.

By sawing one edge along the length, we carefully break the parts on a nail, obtaining the required field strength to create an eternal fan. We assume that the induction is distributed proportionally to the volume. Today we explained clearly how to make a fan with your own hands!

Power supply

Anyone who wants to make a fan with their own hands sees 3 problems: getting a motor, power supply, and making a propeller. The parts must fit together. Three problems solved, you can start making a fan with your own hands. Today there are an abundance of switching power supplies at home. Think about it, it started in the 90s. Gaming consoles, Cell phones, other equipment. Equipment breaks down, switching power supplies remain. The voltage is sometimes non-standard; most motors operate on any voltage. The revolutions will simply change according to the voltage. There's a broken one lying around at home Appliances- Make a fan yourself immediately.

Homemade fan power supplies

People are constantly trying to make a special fan with their own hands. One issue is often beyond the scope of discussion: the power source. The design of the fan itself is so obvious that there is no point in going into more detail. So, it’s clear that there are an unimaginable number of batteries today. Will they be able to work for a long time? The answer is no. As a last resort, take the “crown”, in Soviet time considered a reliable source of energy. The power supply is bad, the power will gradually drop, the speed will decrease, and it will irritate people. 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 screw up 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, you will need a low voltage DC motor. We believe you can find it at home or buy it at a hardware store. How much port power will be: according to old standards, 2–3 W. Another thing is to find a host device with an updated version of the interface (2014 was considered a rarity). The developers promised to deliver 50 W (it’s hard to believe even more). True, there will be more wires, the rated voltages will increase. We remind you that according to tradition, power is supplied to the red (+), black (-) wires. White, green - signal.

It's clear, high power It’s difficult to expect - even if the port supports, the motor will not pull. It is recommended to look for a higher voltage. The motor must be supplied with higher voltage. For example, it is recommended to use a processor cooler. The supply voltage is less than the required 12 volts, the rotation speed will simply decrease. Beware of exceeding it - the motor may burn out.

We are looking for energy, the question is easier to solve than for 3 volts:

12 volt power supply for a homemade do-it-yourself fan

We suggest that you do not assemble a switching power supply, but make a regular one with your own hands. Let us remember that the former are distinguished by small-sized transformers. Therefore, the power supply will be relatively large in size. Will consist of the following parts:

• A step-down transformer. We will not name the number of turns in advance, the voltage is unknown, rectifying it with diodes, we get 12 volts. Of course, you can experiment, like the YouTube video about homemade radios Having captured the reader, we will look for a ready-made solution.
• The bridge is full-wave; by adding three to one diode, we increase the efficiency. Radio components are not very expensive.
• The backbone of the power supply is ready to homemade fan served for a long time, we will straighten the network ripple. After the bridge, we will turn on the low-pass filter and redraw the circuit from the Internet.

The output is a constant voltage with an amplitude of 12 volts. Be careful not to mix up the terminals. Where the “plus” comes out and where the “minus” comes out can be understood by studying the diagram. Below is a drawing of the bridge, look and read the explanations. In radio electronics, the direction of current is indicated opposite to the true one. Charges flow, according to popular belief, in the direction from plus to minus (towards electrons). Reading the diagram, you will see: the emitter of the diode, transistor, marked with an arrow, looks incorrectly. In the direction of movement of positive charges. Each one has marks and is indicated on the diagram by a huge triangle arrow. Therefore, we always find out “plus”, guided by graphic symbols shown in the drawing.

The figure shows: the plus will be on the right, transmitted according to the diode arrow to the lower output terminal. The minus will go up. At AC voltage(roughly speaking) plus and 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 the negative. Take power, low-frequency diodes. Solid size, power dissipation is relatively high. You can calculate using a simple formula taken from training course physics. We multiply the resistance of the open p-n junction (we leaf through the reference book) by the current consumed by the motor, taking a margin of at least 2 times. The motor body contains an inscription indicating the power, which can be divided by the voltage of 12 volts, simply multiplied by 2 - 3, and taken a diode with equivalent power dissipation (see the reference book).

Now let's calculate the transformer... We went here http://radiolodka.ru/programmy/radiolyubitelskie/kalkulyatory-radiolyubitelya/, chose the Trans50 program, we will master it. Please note that there is software that allows you to calculate filter parameters. Do you regret that you decided to make a fan yourself? They offer to choose one of 5 windings. Steel is involved everywhere. You can make do, the losses will be great. The steel forms a magnetic circuit, the energy goes to the secondary winding. It's better to find an old rusty transformer. Times are bad; in the hungry 90s, landfills were littered with plates of scrapped windings. There were no problems with winding the transformers.

It's time to understand what voltage is required for the correct operation of the circuit. A term borrowed from electronics will help: effective voltage alternating current. Voltage at the active resistance creating a thermal effect equal to the constant voltage of the effective amplitude. To obtain the required voltage on the secondary winding, you need to divide 12 volts by 0.707 (one divided by the square root of 2). The authors received 17 volts. The engineering calculation has an error of 30%, let's take a small margin (part of the amplitude up to 1 volt will be lost on the diodes).

As for the secondary winding current (required for calculation), type something like “cooler power” into a search engine. Let's do it together with the readers. Smart articles write: the current consumption of the cooler is indicated on the case. Once you have the required parameter, we’ll plug it into the calculator. The author took the voltage of the secondary winding to be 19 volts. The voltage drop across p-n junctions of powerful silicon diodes is 0.5 - 0.7 volts. Therefore, an appropriate reserve is needed. Smart heads searched and concluded that the processor cooler does not consume more than 5 W, therefore, the current is 5 divided by 12 = 0.417 A. We substitute the numbers into the downloaded calculator, and for the strip core we get the transformer design parameters:

1. The cross-section of the magnetic core for winding is 25 x 32 mm.
2. Window in the magnetic circuit 25 x 40 mm.
3. The magnetic core is finished with a frame for winding wire with a thickness of 1 mm and a cross-section of 27 x 34 mm.
4. The wire is wound along the larger side of the window, leaving a margin of 1 mm from the edges, for 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 core with varnish insulation with a diameter of 0.6 mm (length 16.5 meters, resistance 1 Ohm). Now readers understand: the question of what to make a fan from begins to be decided by the core...

How effective are the proposed technical solutions? Fans are known Ancient Egypt. Evidenced by a Michael Jackson video recommending “Remember the time.” The plot was hardly prepared without the consultation 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 about it...

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