DIY negative ion generator. Air ionizers in air conditioners: are they useful? Ion generator as a means of combating unpleasant odors
Air is one of the vital components of humans. A person can live several days without water, a little longer without food, a person deprived of air can live only a couple of minutes. The ambient air quality in many cities is getting worse and worse that many local news radio stations report air pollution along with weather forecasts. Air pollution is common nowadays. Consequences of air pollution: increased CO2 levels, the greenhouse effect, ozone depletion, and acid rain.
Research
At a time when there was no talk about air pollution, some scientists and experimenters noticed that ionization could improve even clean air. Clean air (mostly 78% nitrogen and 21% oxygen) is typically full of positive and negative ions in a ratio of about 5/4. Researchers have found that when this ratio changes one way or the other, it has an impact on biological systems.
This idea was developed by Fred Sojka, who, in the 1970s, wrote a book called “The Ion Effect.” Citizen Sojka studied the natural phenomena of negatively and positively ionized air. His findings showed that negatively ionized air has significant health benefits.
A few points from his book: negative ions help lift your mood, increase physical performance and better perception of learning, and sterilize the air from harmful bacteria. An abundance of positive ions on the other hand may be responsible for a number of poor quality medical problems such as fatigue, headaches and anxiety.
There are also detractors of this point of view. So before I started designing a negative ion generator, I did some research to see if it would be worthwhile. I have examined approximately 100 worldwide scientific reports on the effects of negative ions from 1973 to the present (1992). I can report that from my review, about 80% noted the beneficial effects of negative ions. More than 19% assured that there was no effect. There was a lot of strong evidence supporting the positive effects of negative ions, and I realized that the ion generator was a worthwhile project.
Ion Generator
The design of the negative ion generator is quite simple (see Fig. 1). The circuit is a high voltage generator. It contains a standard 555 timer which is used to generate square wave pulses. The pulses are applied to the base of the NPN TIP120 transistor. The TIP120 transistor provides enough current to the base of the 2N3055 transistor to turn it on. Each time this happens, autotransformer T2 produces a high voltage. The output of the transformer is connected to a 10 kV high voltage diode. Pay attention to the polarity of the diode.
The author's prototype was built using the point-to-point method (that is, connections due to the leads of parts). This is a good method that can be used in an ion generator as long as some precautions are taken: Make sure that the junctions between C3, C4, D1 should be at least a centimeter apart.
The release points or ionizing pins should be "sharp" to increase the ionization of the air. You can use a sewing needle, for example. Alternative ionizing pins can be made from a small piece of stranded wire. Strip off the insulation 1-2 cm from one end of the wire and separate the veins so that they are more or less evenly distributed (you will get something like a brush). When the wire is connected to a high negative voltage, each wire will behave like an ionizing pin.
The covering on the vent should be plastic. By using a metal screen the generator effect will be greatly reduced because the negative ions that come into contact with the metal screen will be neutralized.
List of radioelements
| Designation | Type | Denomination | Quantity | Note | Shop | My notepad |
|---|---|---|---|---|---|---|
| U1 | Programmable timer and oscillator | LMC555 | 1 | To notepad | ||
| Q1 | Bipolar transistor | TIP120 | 1 | To notepad | ||
| Q2 | Bipolar transistor | 2N3055 | 1 | To notepad | ||
| BR1 | Diode bridge | 4A-50PIV | 1 | To notepad | ||
| D1 | Diode | IMD5210 | 1 | To notepad | ||
| C1 | Electrolytic capacitor | 1000 µF 25 V | 1 | To notepad | ||
| C2 | Capacitor | 0.047 µF | 1 | To notepad | ||
| C3, C4 | Capacitor | 2000 pF 6 kV | 2 | To notepad | ||
| R1 | Resistor | 15 kOhm | 1 | To notepad | ||
| R2 | Resistor | 1 kOhm | 1 | To notepad | ||
| R3 | Resistor | 2.2 kOhm | 1 | To notepad | ||
| R4 | Resistor |
In medicine, an air ionizer is sometimes used for medicinal purposes. In everyday life, they are often used to clean a room from dust and germs and create more comfortable conditions. A simple ionizer can be made using the circuit shown in Fig. 1.
Schematic diagram
In it, high voltage is formed due to the inductive release of back-emf. in coil 1 of transformer T2, which occurs every time the current through winding 2 stops. This voltage is rectified by the diode VD4 and supplied to the emitter E1.
Rice. 1. Negative ion generator circuit.
As a network transformer T1, you can use standardized ones that provide a current of up to 0.8 A in the secondary winding, and T2 can be easily made on the basis of any one used in line scan generators of color TVs, winding a winding of 2 - 8...12 turns, and as winding 1, connect the existing one, containing the largest number of turns (high voltage).
The diagram only shows how high-voltage voltage can be obtained, and in order to use this voltage to create light air ions of negative polarity (they are the ones that have useful properties), you will need to make an E1 emitter. It is made of wire and must have many needle-like (sharp) ends.
The shape and dimensions of the structure do not matter much. Various versions of such emitters can be seen in the store - they are part of household ionizers manufactured by industry (the so-called “Chizhevsky A.L. chandelier”).
If the radiator is small in size, it is advisable to install a fan to accelerate air circulation in the working area (motor M1 is shown in the diagram); in this case, the process of formation of air ions occurs more intensively.
Literature: For radio amateurs: useful diagrams, Book 5. Shelestov I.P.
Air ionizers in air conditioners: are they useful?
Recently, heated debates have flared up among connoisseurs and admirers of air conditioners over how useful or, conversely, useless air conditioners with negative ion generators, or, simply put, with ionizers, which have so quickly become fashionable. This question could be completely left to theorists and not pay special attention to it, if such judgments had not appeared that cast doubt on the very expediency of such a technical innovation.It would seem that engineers and inventors have come up with everything in recent years to equip the air conditioner with all conceivable and inconceivable technical innovations. How much money and man-hours were spent to achieve one single goal - to attract attention to their brand, to retain demand for their air conditioners by any means.
PR or revolutionary achievement?
Frankly speaking, in this uncompromising competition for sales areas, not all its participants always work, so to speak, with white gloves. Many technological innovations are presented under the guise of outright PR, presenting, under the guise of revolutionary technologies, quite ordinary and often functional baits that do not bring anything to the end user of the air conditioner.An opposite point of view on the ionization process.
There is another point of view on the same question about the advantages and disadvantages of saturating the air with negative ions. Thus, some experts believe that in the process of the air conditioner releasing charged microparticles, the process of deodorizing the air mass is carried out and at the same time filling the environment with additional oxygen, which has an extremely beneficial effect on the well-being and emotional and physical mood of people located in the area of the air conditioner.If we take into account that, as a rule, air conditioners with an ionization system installed in them have, as additional useful devices, a plasma filter, the ability to disinfect air, and the function of ultra-fine air purification, then it becomes clear that the consumer wants to focus his attention on this air conditioner with all modern air treatment characteristics.
Ion generator as a means of combating unpleasant odors.
Another nuance that should be remembered when doing this is that it is believed that the ion generator of the air conditioner helps cleanse the environment from a wide variety of pathogenic microbes that fill almost the entire space of our home. This very valuable ability of an air conditioner cannot go unnoticed by true lovers of cleanliness in the house.And finally, many of those surveyed during the studies really believe that air enriched with ions using an air conditioner acquires a special smell of freshness. Many compare this feeling with the state that a person experiences when being near a large body of water or a working fountain. One way or another, the buyer always has the final say in the determination. Read also.
In general, the air ion generator consists of a power source, a high-voltage unit and an emitter. In Fig. Figure 1 shows a diagram of a negative air ion generator similar to the one proposed by the famous scientist A.L. Chizhevsky in 1931. High voltage generator block is a circuit for converting and multiplying the power supply voltage to 50 kV. The power source includes transformer Tr1, a bridge rectifier, and capacitor C1 with an output voltage of 12 V. The core of transformer Tr1 of the source is assembled from plates of the ShZO type (set thickness 20 mm). The primary winding of the transformer contains 1500 turns of PEV-0.4 wire, the secondary winding contains 90 turns of PEV-0.9 wire. Instead of this power source, any other one with a permissible load current of at least 1.5 A will do.
The windings of the transformer Tr2 of the high-voltage unit are wound on the core from the line transformer of the TV (type TVS-110). Winding I consists of 14 turns of PEV-0.8 wire (tap from the middle); winding II - of 6 turns PEV-0.8 (tap from the middle); winding III - from 8000 turns of PEL-SHO-0.8 (or from 10,000 turns of PELSHO-0.1). In winding III, every 800 turns, an insulating fluoroplastic gasket 0.1 mm thick (from FT-type capacitors) is placed on the wires. It is allowed to use capacitor paper with a thickness of 0.2...0.3 mm, wound in 2...3 layers. The same gaskets must be used to separate windings I and II, as well as II and III, from each other.
Details. The transistors VT1 and VT2 (KT837A) indicated in the diagram can be replaced with transistors P217 with any letter, GT806 B...D, KT837 with any other letter. Instead of rectifier posts VD5...VD10, KTs105D, KD201D, D1007 are suitable. High-voltage capacitors - any, designed for a voltage of at least 10 kV.
The generator elements are placed on a mounting plate made of getinax or textolite 2 mm thick, the installation of radio elements is hinged. The housing of the generator block is made of aluminum with a thickness of 1...2 mm; U-shaped radiators for transistors are made of the same material. The assembled unit is placed near the location where the emitter is suspended so that the 50-kilowatt output is as short as possible. For output, take a high-voltage wire of an automobile ignition system or a RK-75 television cable with the wire braid removed.
Emitter- a screen, which is a copper ring to which a mesh of copper wire with a diameter of 0.3...0.5 mm is soldered (ring wire diameter is 2 mm). The insulation from the wires is, of course, removed. The grid has square cells, the convex part of the screen is directed downwards (Fig. 2). Sharply sharpened pieces of copper wire with a diameter of 0.25...0.5 mm and a length of 45...50 mm are soldered into the corners of the cells. Suspensions are attached to the ring - 3 copper wires with a diameter of 1 ... 2 mm, turned at an angle of 120° and soldered above the center of the emitter. The emitter is suspended from the ceiling using a ring made of dielectric material. The wire from the high-voltage unit is connected to the suspension wires or to the ring. To monitor the performance of the “Chizhevsky chandelier,” a ribbon of tissue paper measuring 10x80 mm, folded in half, is suspended from the wire of the emitter grid. During normal operation, the lower ends of the ribbon diverge by 30° or more.
A treatment session with negative aeroions is carried out in a well-ventilated and clean room at a temperature of 18...25 ° C and normal humidity. The first procedure lasts 10 minutes, then, increasing the procedure time by 2...3 minutes daily, the duration of the procedure is increased to 30 minutes. The procedures are carried out daily, the course of treatment is 20...25 procedures. As a rule, they return to the second course after 6...8 weeks. To prevent diseases, the “Chizhevsky chandelier” is turned on every other day for 5...10 minutes.
Treatment using the “Chizhevsky chandelier” is recommended for mild to moderate bronchial asthma; for sinusitis, rhinitis, pharyngitis, laryngitis, bronchitis, burns, wounds, trophic ulcers, neuroses; also with increased fatigue, insomnia, headache.
Contraindications: severe forms of bronchial asthma, pulmonary emphysema, chronic ischemic heart disease with symptoms of decompensation, severe cerebral atherosclerosis, active pulmonary tuberculosis, severe general exhaustion of the body.
This design of the air ion generator has the following disadvantages: high labor intensity in manufacturing, as well as the need to periodically turn it off. Much more attractive for self-production is the design of the generator, where nickel or nichrome wire with a diameter of 0.1...0.3 mm is used as ionizing electrodes. The use of wire as electrodes makes it possible to obtain a more uniform distribution of air ions in the room than with needle electrodes. A very important advantage of wire electrodes is that during their operation ozone and nitrogen oxides are not released. Moreover, generators with such electrodes can operate for a long time without causing an overdose.
The circuit of an air ion generator generating a constant negative voltage of 20 kV to power wire electrodes is shown in Fig. 3. In this design, the frequency of the supply voltage of 50 Hz is increased to 1000 Hz by the transistor converter VS1. Shunting of the dinistor with diode VD1 is used to reduce the bias current of the magnetic circuit, which leads to an increase in the voltage at the output of the transformer. Thus, the mains voltage is increased using a transformer and a voltage multiplier, and then supplied to the wire electrodes through the limiting resistor R4.
Details. The circuit uses MLT type resistors; capacitor C1 of the MBM brand, designed for a voltage of at least 500 V (it can be replaced with capacitors of the MBG; MBGO; K42-11; K42U-2 type). Capacitors S2...C5 are polystyrene type POV, but with a voltage of 10 kV (they can be replaced with capacitors like KBG, K73-12). Instead of the VD1 diode, it is not forbidden to install any other diode with a pulsed reverse voltage of at least 800 V, for example, KD209B or MD217. A ready-made high-voltage transformer, type TVS-90PZ, was used. In the absence of a fuel assembly, the high-voltage transformer is wound on an electrical cardboard tube with an outer diameter of 8 mm and a length of 150 mm, inside which a rod of ferromagnetic material is placed (according to the size of the tube). Primary winding The transformer contains 60 turns of PEV-0.3 wire, it is wound directly onto the frame. Then the winding is insulated (wrapped) with 2...3 layers of capacitor paper or a layer of fluoroplastic tape. Secondary winding contains 5 thousand turns of PELSHO-0.12 wire, wound turn to turn (winding length 70 mm). Each layer of the secondary winding wire is separated from the next one with one turn of fluoroplastic tape or two turns of capacitor paper. The finished transformer is impregnated with paraffin (bakelite varnish is allowed, as well as BF-2 or BF-4 glue). It is better to choose a ready-made multiplier for voltage 18...22 kV.
Wire made of nichrome, nickel, constantan or other alloy with high resistivity is suitable as a material for a wire electrode. The electrode wires are located around the perimeter of the room. It is allowed to pull a single electrode diagonally or in the middle of the ceiling, but in this case the efficiency of the generator is reduced by about a third.
When hanging a wire electrode in a room, certain requirements must be observed. So, the distance of the wire from the walls should be more than 300 mm; from the ceiling - more than 500 mm; between wires - more than 2500 mm. The height of the wires from the floor is 2500 m. If these requirements are violated, the number of generated air ions decreases and the uniformity of their distribution in the room deteriorates.
The wires are secured in the corners using a piece of fishing line with a metal washer at the end (Fig. 4). Thus, the wires screwed to one washer cannot fail to close, that is, they form a single circuit. The free end of each line is attached to the wall. For standard living rooms, four stretchers are usually enough. The formation of nodules on the wire electrode is undesirable; slight sagging does not affect the efficiency of the generator.
The high-voltage rectifier is mounted on a board made of textolite or getinax 2 mm thick; The rectifier housing is cut from sheet metal with a thickness of 1...1.5 mm. Rectifier
hung on the wall at the same height as the wire. The limiting resistor and the wire electrode are connected by a piece of high-voltage wire 150...250 mm long (the high-voltage and electrode wires are connected by winding several turns of PEV-0.2 copper wire with the insulation removed).
The concentration of negative ions in the breathing zone of this generator reaches 800,000 ions/cm3. To control the operation of the generator, a tissue paper ribbon is attached to the electrode wire (as in the case of the “Chizhevsky chandelier”).
Even easier to manufacture is a negative air ion generator, the diagram of which is shown in Fig. 5. Its assembly is similar to the generator shown in Fig. 3, with the only difference that the number of turns in the secondary winding of the transformer when manufactured independently is 2000 turns. The ion concentration of this generator is 300,000 ions/cm3.
Electrically charges air molecules and operates at high voltage. Negative ions, or anions, are particles with one or more extra electrons, giving the particle a total negative charge. Cations are positively charged ions that are missing one or more electrons, creating a net positive charge. Most commercial air purifiers produce negative ions. Another type of air ionizer is an ESD ionizer, or balanced ion generator, which neutralizes static charge.
Soviet scientist and inventor Alexander Chizhevsky created the so-called Chizhevsky chandelier in 1918. It was the first modern ionizer.
Video about air ionizer
Ionic air purifiers
The image shows the ionizer and air purifier with the dust collection plates removed.
Air ionizers are used in air purifiers. The dust particles are attracted to the electrodes by an action similar to static electricity. These ions are de-ionized when searching for grounded conductors such as walls and ceilings. To increase the efficiency of this process, some commercial instruments are equipped with such surfaces inside the device. The incidence of nosocomial infections in British hospitals has prompted the National Health Service (NHS) to investigate the effectiveness of anions in air purification. The severe acute respiratory syndrome pandemic has increased demand for ionizers for home use in the Far East and Japan. There, many products were equipped with negative ion generators, such as toothbrushes, refrigerators, air conditioners, air purifiers and washing machines. There are no specific standards for such devices. Laptop manufacturer ASUS has installed a built-in air ionizer in the N51Vf model.
Ions and ozone
Ionizers should not be confused with ozone generators, even though both devices operate similarly. Ionizers typically use electrostatic plates to generate positively or negatively charged gas ions, such as N 2 - or O 2 -, and cause the particles to stick together under an action similar to static electricity. In ozone generators, an additional oxygen ion is attracted to the O 2 molecule. These generators operate using a corona lamp or ultraviolet light. Even the best ionizers produce small amounts of ozone.
At high concentrations, ozone can be toxic to airborne bacteria and can destroy or destroy these sometimes infectious organisms. However, the permissible concentration is toxic enough to humans and animals that the US Food and Drug Administration strongly recommends that ozone therapy not be used as a medical treatment. It has taken action against those who do not comply with this requirement. Ozone is a highly toxic and overly active gas. The average daily dose is over 0.1 ppm. (0.2 mg/m3) is not recommended and can damage the lungs and even the cells of the olfactory bulbs.
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The photo shows the effect of sterilizing air with negative ions in a chamber filled with Salmonella enteritidis bacteria. The sample on the left is not processed, the sample on the right is processed.
Trial Consumer Reports
Non-profit magazine about product testing in the USA Consumer Reports published in October 2003 that air ionizers do not meet a high enough standard compared to conventional HEPA filters. The exception was a combined device that operated on a blower, with the help of which air moves during the process of its ionization. In response to this publication by The Sharper Image, the manufacturer of air ionizers, among other products, filed a lawsuit against the Consumer Society (publishers Consumer Reports) for defamation of goods. The magazine gave the Ionic Breeze and other popular units a "negative rating" for their low clean air delivery ratio (CADR). CADR measures the amount of purified air circulating over a short period of time and was originally intended to measure the ratio of average air purifiers. The Sharper Image stated that this test was a poor way to evaluate the Ionic Breeze because it does not take into account other features such as 24-hour long lasting cleansing, ease of handling and quiet operation. The U.S. District Court for the Northern District of California subsequently dismissed The Sharper Image's complaint and dismissed the case for the reason that The Sharper Image failed to prove that all of the statements made were false. Consumer Reports. According to the final court decision in May 2005, The Sharper Image had to pay 525,000 USD to the Consumer Society for legal costs.
