RU2301377C2 - Method of ionizing air and bipolar ion generator - Google Patents

Abstract

FIELD: air conditioning.

SUBSTANCE: method comprises flowing air through the system of corona electrodes arranged in the air duct. The system is energized by alternating voltage pulses whose amplitude within both of the half periods exceeds the threshold of corona discharge. The system of corona electrodes is divided into two same groups that are positioned one in the vicinity of the other. The high-voltage pulses are selected in polarity and the pulses of different polarities are directed to different groups of corona electrodes. The concentration of ions and unipolarity coefficient of the ions is controlled by means of changing the duration of pulses of positive and negative polarity. The bipolar ion generator comprises the second group of corona electrodes identical to the first group and positioned in the vicinity of the first group.

EFFECT: enhanced efficiency of ionization and reliability and longevity of corona electrodes.

4 cl, 3 dwg

Description

The invention relates to methods and techniques for processing air and can be used in everyday life, in medical, office, training rooms with television, computer and other office equipment for enriching the air with ions of both signs, neutralizing all kinds of electrostatic fields on various surfaces, objects and clothes of people, and also for cleaning air from dust, bacteria and spores of fungi. It can also be used in industrial (not polluted) rooms for the same purposes and in rooms for storing various food products.

There are various methods of ionization of air, in which air is passed through a system of corona electrodes installed in the blown duct, to which:

1. High-voltage high-frequency voltage passed through the diode, i.e. pulsating voltage of negative polarity [see, for example, SU 107932 A (P.K. Pruler and others), 1957]. With this method, air ions of only negative polarity are obtained, and we need bipolar ionization of air.

2. High voltage voltage is either negative or positive polarity, with an interval of polarity reversal of several minutes [see, for example, US 3936698 A (MEYER), 02/03/1979]. With this method, air is ionized with negative ions for several minutes for therapeutic purposes, then the polarity of the ions is changed for the same time to remove the generated negative electrostatic charges on the clothes, objects and body of the patient. The method is very inefficient and uncontrollable, except for ionization time intervals. And it’s not entirely wise to create electrostatic fields that impede the further passage of ions to the consumer, and then spend time eliminating them. In naturally ionized air in nature, ions of one and the other sign, as a rule, are distributed fairly evenly in the volume of air.

3. Alternating high-frequency voltage in the form of alternating packets of asymmetric high-voltage pulses [see, for example, RU 42629 U1 (V. P. Reuta, A. F. Tuktagulov), 12/10/2004]. With this method of bipolar ionization, the concentration of ions of one and the other sign is controlled by changing the duration and duty cycle of high voltage pulses of positive and negative polarity. Using this method of ionization also does not allow to obtain a uniform distribution of ions over the volume of air. In addition, the use of asymmetric high-voltage pulses reduces the ionization efficiency due to the fact that the reverse emissions of the pulses create inhibitory fields that absorb part of the formed ions, reducing the ionization efficiency.

The closest type of voltage used for ionization is the method of air ionization, in which air is passed through a system of corona electrodes installed in the blown air duct, to which alternating voltage pulses are supplied, the amplitude of which in both half periods is higher than the corona threshold [see, for example, SU 842347 A (KAZANSKII A.I.), 06/30/1981].

This method is ineffective at low air flow rates through the duct, because the lower the air flow rate, the lower the high-frequency pulse repetition rate should be, so that the formed ions have time to fly off a sufficient distance from the corona electrodes, otherwise a reverse polarity pulse supplied to the same electrodes will slow them down. And in inhabited premises it is not permissible to use high air flow rates.

It should be noted that the methods according to paragraphs 1) and 2), where high-voltage voltage of the same sign is applied to the groups of corona electrodes, has one more drawback - fast contamination of the corona electrodes and their wear due to unidirectional radiation or absorption of electrons and ions from corona or corona electrodes .

The objective is to increase the efficiency of air ionization and improve the uniform distribution of ions of both signs in ionized air. An additional task when designing a bipolar ion generator that implements the proposed method of air ionization is to increase the reliability and durability of the corona electrodes of the generator.

To do this, in the method of air ionization, in which air is passed through a system of corona electrodes installed in the blown air duct, to which alternating voltage pulses are supplied, the amplitude of which in both half periods is higher than the corona threshold, the system of corona electrodes is made of two identical and adjacent groups of electrodes, high voltage pulses are selected by polarity and direct pulses of different polarity to different groups of corona electrodes, and the concentration of ions and the coefficient of unipo The ion polarity is controlled by independently changing the pulse durations of positive and negative polarity. In addition to this, at equal intervals of time, the polarity of the high voltage pulses supplied to different groups of electrodes is changed.

To implement this method of air ionization, a special bipolar ion generator is required. Although various bipolar ion generators are known, they are not suitable for the implementation of this method of air ionization by the principle of action.

The closest in the set of functional units and their circuit solution is a bipolar ion generator containing a group of corona electrodes located in the blown air duct connected to the output winding of a high voltage transformer, the primary winding of which with a voltage boost capacitor connected in series with it, is included in the diagonal of the voltage bridge switch connected to positive and common power buses, in which the first half of the switch is made according to the complementary circuit about the emitter follower, and the ion concentration control unit [see, RU 42629 U1 (B.P. Reuta et al.), 12/10/2004].

In the prototype, an air ionization method is used, in which alternating packets of high-voltage pulses are fed to the same group of corona electrodes, i.e. positive and negative ions are alternately generated, and the unipolarity coefficient of the ions is controlled by changing the ratio of the duration of the pulse packets of positive and negative polarity. The principle of operation incorporated into the prototype does not allow using it directly for the implementation of the proposed method of air ionization.

The objective of the invention is the creation on the basis of the prototype with minimal circuit complication of a bipolar ion generator, with which it will be possible to implement the proposed method of ionization of air.

For this, a bipolar ion generator containing a group of corona electrodes located in the blown air duct connected to the output winding of a high-voltage transformer, the primary winding of which with a voltage-boosting capacitor connected in series with it, is included in the diagonal of the voltage bridge switch connected to the positive and common power buses, in which the first half of the switch is made according to the scheme of a complementary emitter follower, and the ion concentration control unit is equipped with they are connected to the positive and common power buses by a third switch, a second group of corona electrodes identical to the first group and located next to it, two diodes and a second high-voltage transformer, the output winding of which is connected to the second group of corona electrodes, the primary winding is connected in parallel with the primary winding of the first transformer , and both of these windings are connected to the output of the second switch via on-off diodes, both transformers are in-phase connected, and the control unit The ion concentration is made from a series-connected multivibrator with an adjustable pulse repetition rate and a pulse shaper made on the EXCLUSIVE OR logic element, the first input of which is connected to the output of the multivibrator, also connected through two parallel-connected circuits consisting of potentiometers and diodes connected in series with on / off switching, the second input of the logic element, to which the time-setting condensation connected to the common bus is additionally connected Oh, the signal inputs of three voltage switches are connected either to one or to different outputs of the multivibrator, and the second and third voltage switches are made according to the scheme with three states at the output, in which the control inputs of the “third” state are combined and connected to the output of the pulse shaper, In this case, the second switch is translated into the “third” state by the “zero” signal, and the third switch by the “single” signal. In addition to this, the bipolar ion generator is equipped with a timer with a pulse width of two and an electromagnetic relay with two groups of changeover contacts, which is the load of the timer, and contact groups of relays are connected between the diodes and the primary windings of the transformers.

Figure 1 presents the main diagram of a bipolar ion generator that implements the proposed method of ionization of air.

Figure 2 presents graphs of pulses at individual points in the circuit of figure 1.

Figure 3 presents a part of the circuit of figure 1, which can be included additional nodes in the form of a timer and electromagnetic relay.

In the drawings, the following notation:

1 - multivibrator;

2, 3, 21, 31 - inverters;

4, 10 - time-consuming capacitors;

5 - decoupling resistor;

6 - current limiting resistor;

7, 11, 13 - potentiometers;

8 - pulse shaper;

9 - logical element "EXCLUSIVE OR";

12, 14, 32, 39, 45 - diodes;

15 - the third voltage switch with three states at the output and with the inversion of the signal;

16, 23, 27 - n-p-n transistors "Darlington";

17, 24, 28 - p-n-p transistors "Darlington";

18 - power bus;

19, 29 - logical elements "2OR-NOT";

20, 30 - logical elements “2I-NOT”;

22 - the first voltage switch;

25 - booster capacitor;

26 - the second voltage switch with three states at the output and with the inversion of the input signal;

33 - the primary winding of the transformer 34 with a high voltage secondary winding 35;

36 - duct;

37 - the first group of corona electrodes;

38 - accelerating electrodes;

40 - the primary winding of the transformer 41 with a high voltage secondary winding 42;

43 - the second group of corona electrodes;

44 - electromagnetic relay with two groups of 47 and 48 changeover contacts;

46 - timer;

“A” and “B” are the directions of flows of bipolar ionized air;

"C" - the direction of air flow at the inlet of the ion generator.

The dots at the windings 33, 35 of the transformer 34 and at the windings 40, 42 of the transformer 41 indicate the conditional start of the windings;

And ₁ - voltage pulses at the output of the multivibrator 1;

And ₁₈ is the voltage level on the bus 18;

And ₈ - voltage pulses at the output of the pulse shaper 8;

And ₂₅ is the voltage on the boost capacitor 25;

And ₃₃ , And ₄₀ - voltage pulses on the windings, respectively, 33 and 40;

t is the time;

t ₁ ÷ t ₈ - time instants.

Multivibrator 1 (Fig. 1) has a standard circuit (see, for example, R. Melen, G. Garland. Integrated circuits with CMOS structures. M., "Energy", 1979, pp. 105-107, Fig. 6 -1) and consists of series-connected inverters 2 and 3, a timing RC circuit consisting of a capacitor 4 and resistors 6 and 7, and a decoupling resistor 5. Resistor 6 is current-limiting for inverter 2, and resistor 7 can change the frequency within certain limits following pulses And ₁ (figure 2) at the output of the multivibrator 1. The output of the multivibrator 1 is connected to the signal inputs:

pulse shaper 8;

the first switch 22;

second switch 26;

third switch 15.

The pulse shaper 8 along the edge and the pulse drop of the multivibrator 1 is assembled on the logic element 9 “EXCLUSIVE OR”, the first input of which is connected to the output of the multivibrator 1, and the second input is connected there through two parallel-connected circuits consisting of potentiometers 11 or 13 and connected in series , respectively, diodes 12 or 14 with a counter inclusion. In addition to the second input, a timing capacitor 10 connected to a common bus is connected. Potentiometer 11 is used to control the duration of pulses at the output of the shaper 8, formed along the front of the output pulses of the multivibrator 1, and a potentiometer 13 control the duration of pulses at the output of the shaper 8, formed by the decline of the output pulses of the multivibrator 1. [A detailed description of such a pulse shaper is presented in the application for the utility model "Pulse Shaper" No. 2005109641/09 (011358) dated 04.04.2005; authors: V.P. Reuta, A.F. Tuktagulov].

The output of logic element 9, which is the output of pulse former 8, is connected to the third-state control inputs of switches 15 and 26. These switches are made in almost the same way on a complementary pair of Darlington transistors npn type 16 or 27 and pnp type 17 or 28, in which the emitters are combined and are the outputs of the switches, and the collector is connected between the power bus 18 and the common bus. The base of the pnp transistors are connected to the outputs of the logic elements “2OR-NOT”, respectively, 19 or 29, and the bases of the pnp transistors are connected to the outputs of the logic elements “2I-NOT”, respectively, 20 or 30. One input of the logical elements 19 and 20 are combined and connected to the signal input of the switch 15, and similar inputs of the logic elements 29 and 30 are connected to the signal input of the switch 26.

In the switch 15, the third state control input is connected to the first input of the logic element 19 and with the input of the inverter 21, the output of which is connected to the second input of the logic element 20. In the second switch 26, the third state control input is connected to the first input of the logic element 29 through the inverter 31, and to the second input of the logic element 30 - directly. Due to the different connection points of the inverters 21 and 31, the switches 15 and 26 are transferred to the third state, in which the output of the switch 15 or 26 is isolated from the power buses by the high resistance of the locked transistors 16, 17 or 27, 28 with different signals. So, the switch 15 goes into the third state if there is a third state of the “single” signal at its input, and the switch 26 is “zero”. The first switch 22 is made according to the simplest scheme of a complementary emitter follower on Darlington transistors npn 23 and pnp 24, the emitters of which are combined and are the output of the switch, the bases are combined and are the signal input of the switch, and the collector is connected between the power bus 18 and the common bus.

It should be said here that Darlington transistors are usually called integral composite transistors (see, for example, Claude Galle. Useful tips on the development and debugging of electronic circuits. DMK, Moscow, 2003, p. 63, Fig. 2.27), which may have including resistors and protective diodes (see, for example, the Handbook. Foreign microcircuits, transistors, diodes. A ... Z. "Science and Technology", St. Petersburg, 2003, p. 483). In the switch 26, the transistors 27, 28 must include protective diodes. If there are no such diodes in the used transistors, then they need to be installed additionally parallel to the emitter-collector junction of each transistor. And in the switch 15 such diodes should not be.

Let us return to the circuit of FIG. 1. Here, the first 22 and second 26 switches form a bridge, the diagonal of which includes a series-connected boost capacitor 25 and two primary windings: 33 transformers 34 and 40 of transformer 41; the second ends of these windings through counter-connected diodes, respectively, 32 and 39 are connected to the output of the switch 26 either as shown in figure 1, or through the contact groups 47 and 48 of the relay 44 - as shown in figure 3. Here, the relay 44 together with the protective diode 45 is included as a load of the timer 46 between the output of this timer and the power bus 18.

The secondary winding 35 of the transformer 34 is connected to the corona electrodes 37 and accelerating electrodes 38 connected to a common bus located in the air duct 36 blown in the direction of arrows “C”. The secondary winding 42 of the transformer 41 is connected to the corona electrodes 43 and the same accelerating electrodes 38.

Typically, the corona electrodes 37 and 43 are in the form of needles or pointed pins, and the accelerating electrodes 38, as a rule, are in the form of rings mounted coaxially with the corona electrodes 37 and 43.

It should be noted that the scheme of the bipolar ion generator shown in Fig. 1 is not the only possible solution to the problem. For example, if the signal input of switch 22 is not connected as shown in Fig. 1, but to the second output of multivibrator 1, which is the common connection point of inverters 2 and 3, then in this case the second 26 and third 15 switches should not be inverters, as shown in figure 1, and voltage followers, as, for example, in the prototype. For exotic, you can combine the connection points to the outputs of the multivibrator 1 of the signal inputs of all three switches, which will necessitate a change in the internal structure of the second 26 and / or third 15 switches. In addition, both the repeater and the inverter having three output states, for the same input and output parameters, can have different internal circuit solutions [see Applications for utility model “Electronic voltage switch with three states at the output” No. 2005109639/09 (011356) dated 04.04.2005 and No. 2005109640/09 (011357) dated 04.04.2005, the authors of both applications: V.P. Reuta and A.F. Tuktagulov]. In the first application eight options are described, and in the second application two more variants of electronic voltage switches with three states at the output are described. Moreover, half of them are switches without signal inversion, and the second half are with signal inversion. According to another gradation: half of these switches are transferred to the third state by a “zero” signal at the control input of the third state, and the second half by a “single” signal. And in the circuit of a bipolar ion generator, any of the circuits described in the applications can be used as second 26 and third 15 switches. Therefore, in the claims, the internal arrangement of these switches is not specified.

The first 22 switch is a regular complementary emitter follower on Darlington transistors 23 and 24 and is widely used in digital technology (see, for example, Claude Galle. Useful tips for the development and debugging of electronic circuits. DMK, Moscow, 2003, p. .106-107, fig. 2.67).

As the timer 46 (FIG. 3), any of a variety of known timers can be used, capable of generating two pulses symmetrical with duty cycle at an ultra-low frequency, for example, with a period of tens of minutes. Such a timer can be implemented, for example, on a specially created chip 4047 (see, for example, ONPartala. Digital CMOS chips. Reference book. "Science and Technology", St. Petersburg, 2001, pp. 111-113 ), if you add a key to it on the transistor to control the operation of relay 44. And, finally, as high-voltage transformers 34 and 41, either line-type transformers from small-sized semiconductor TVs or high-voltage transformers specially made for ionizers can be used.

Some explanations for the graphs of figure 2. For voltage And ₂₅ on the boost capacitor 25, such a voltage And ₂₅ is taken as positive when the voltage on the left side of the capacitor 25 in FIG. 1 is positive relative to the right side. For pulses And ₃₃ and And ₄₀ on the primary windings 33 and 40 of the transformers, respectively, 34 and 41, the voltage on these windings is taken as positive, when the current through the windings flows from the beginning of the windings marked with dots to the end of the windings, i.e. when a positive voltage is applied to the beginning of the windings with respect to the ends of the windings. The same applies to the secondary windings of transformers, in which the direction of the currents coincides with the direction of the currents in the primary windings. Therefore, with a positive pulse And ₃₃ on the primary 33 of the transformer 34 on its secondary 35 and, accordingly, on the corona electrodes 37, the high voltage pulse will have a negative polarity, due to which negative ions will form in the corona electrodes 37 in the blown air. If you turn off the air blowing, then all the ions will settle on the accelerating electrodes 38. With a negative pulse And ₄₀ on the primary 40 of the transformer 41 on its secondary winding 42, a high-voltage pulse positive relative to the common bus will be generated, due to which positive ions will form at the corona electrodes 43 in purged air.

Considering the graphs in figure 2, you can see that the process of formation of the corona pulses has a cyclic nature. The time of one cycle, during which one corona pulse of different polarity is formed, arriving at different corona electrodes 37 and 43, is equal to the pulse repetition period And ₁ at the output of the multivibrator 1. In turn, this cycle consists of four clocks determined by combinations of pulses And ₁ at the output of the multivibrator 1 and And ₈ at the output of the pulse shaper 8.

Implement the considered method of ionization of air using a bipolar ion generator of figure 1 as follows.

Before turning the ion generator on for the first time, the adjusting potentiometers 7, 11 and 13 are set to a certain middle position, from which it will then be easier to change the pulse parameters in both directions. Turn on the supply voltage And ₁₈ , with the help of which all the nodes of the ion generator are brought into operation. Using a multivibrator 1, a sequence of pulses And _{1 is formed} , the repetition rate of which is set by potentiometer 7. These pulses are used to form 8 pairs of pulses And ₈ using a pulse shaper along the leading edge of pulses And ₁ (from t ₁ to t ₂ and from t ₅ to t ₆ ) and on the trailing edge of the pulses And ₁ (from t ₃ to t ₄ and from t ₇ to t ₈ ). We will conditionally call the pulses generated on the rising edge odd, and the pulses formed on the falling edge even. The duration of the odd pulses is changed using the potentiometer 11, and the duration of the even pulses is changed using the potentiometer 13. Using these pulses (if any), the third voltage switch 15 is turned into a third state (i.e., turned off) and the second one is put into operation voltage switch. And the output pulses And ₁ from the output of the multivibrator 1 is additionally fed to the signal inputs of the first 22, second 26 and third 15 voltage switches. As a result of the combination of pulses And ₁ and And ₈ at the inputs of the switches 15 and 26, the entire cycle of formation of a pair of bipolar high-voltage pulses is divided into four clock cycles.

In the first cycle from t ₁ to t ₂ and from t ₅ to t _{6, the} pulses And ₁ and And ₈ have a "single" value, due to which the signal pulse And ₁ open the transistor 23 in the first 22 switch, close the transistor 24, and in the second switch 26, the transistor 28 is opened and the transistor 27 is closed. Due to this, the total voltage of the power source And ₁₈ and the charged capacitor 25 - And ₂₅ are applied to the primary 33 winding of the transformer 34. Due to the flow of current from the supply bus 18 through an open transistor 23, a capacitor 25, a winding 33, a diode 32, and an open transistor 28 to a common bus on a winding 33, a voltage pulse And _{33 is} generated, which is increased by the transformer 34 in amplitude and in reverse polarity due to the corresponding turning on the secondary 35 of the transformer winding is fed to the corona electrodes 37 relative to the accelerating electrodes 38, between which ionization of the air blown past these electrodes along the arrows “A” is carried out, enriching it with negative ions. The duration of this process is set by the duration of the odd pulse And ₈ , changing its duration by potentiometer 11. After the end of the odd pulse And ₈ from t ₂ to t ₃ and from t ₆ to t ₇ form the second cycle cycle, during which the I8 signal is transferred to the third state (turn off) the second 26 switch, locking the transistor 28 when the transistor 27 is locked, and the third 15 voltage switch is put into operation, inside which a “single” signal And ₁ transistor 17 when the transistor 16 is locked 16. During this cycle (see graph And ₂₅ in FIG. 2), the boost boost capacitor is recharged to plus H ₁₈ from the supply bus 18 through the still open transistor 23 and through the opened transistor 17 to the common bus. At the same time, the energy accumulated in the winding 33 of the transformer 34 is discharged. Since the current in the transformer winding cannot instantly stop or change its direction, it will flow with attenuation through the diode 32, the internal protection diode of the locked Darlington transistor 27 to the power bus 18 until the voltage And ₂₅ on the capacitor 25 reaches zero . Due to this process, the And ₃₃ pulses, like the And ₄₀ pulses, have a littered trailing edge.

In the third step, from t ₃ to t ₄ and from t ₇ to t ₈ , when the pulse And ₁ takes a "zero" value, and the pulse And ₈ again takes a "single" value, the duration of which is controlled using a potentiometer 13, the pulse And ₈ again turn off the third 15 switch and turn on the second 26 switch. At the same time, the transistor 23 is turned off from the output of the multivibrator 1 in the first 22 switch and the transistor 24 is opened, and in the second 26 switch the transistor 27 is opened, leaving the transistor 28 closed. Due to this operation, the total voltage is applied to the primary 40 of the transformer 41 charged almost to AND ₁₈ capacitor 25 (minus to the beginning of the winding 40) and voltage And ₁₈ from the power bus 18 (plus to the end of the winding 40). From bus 18 through an open transistor 27, diode 39, winding 40 and capacitor 25, current flows to a common bus, with which a negative pulse And _{40 is formed} on the primary 40 of the transformer 41, which is converted into a high voltage pulse of positive polarity using secondary winding 42. This pulse is applied to the corona electrodes 43 with respect to the accelerating electrodes 38, thereby creating a corona discharge between these electrodes, due to which the air blown past the said electrodes in the direction of arrows “B” will be ionized by positive ions.

After the end of the And ₈ pulse from t ₄ to t ₅ and from t ₈ onwards, the fourth clock cycle occurs during which the “And” zero value of And ₈ pulse turns off the second 26 switch and turns on the third 15 switch, in which And ₁ opens with a “zero” signal the transistor 16, leaving the transistor 17 locked. Due to this operation, the capacitor 25 is recharged to a negative voltage equal to | And ₁₈ | from the power bus 18 through the open transistor 16 and the open transistor 24 of the first switch to the common bus. At the same time, through the protective diode of the Darlington transistor 28 and the diode 39, a discharge from the stored energy of the winding 40 of the transformer 41 is produced according to the same principle that was used to discharge the winding 33 of the transformer 34.

At time t _{5, the} four-cycle cycle of the formation of high-voltage pulses ends and the next similar cycle begins.

Thus, using a multivibrator 1 and a pulse shaper 8, which together form an ion concentration control unit, pairs of pulses are formed with independent control of the duration of these pulses, which allows independent control of the concentration of ions of positive and negative polarity, which is proportional to both the duration and repetition rate these pulses, which control the change of the pulse repetition frequency of the multivibrator and _one which, moreover, are used for the selection of high-voltage x pulse polarity. And since the unipolarity coefficient of ions is determined by the ratio of the concentration of positive ions in a unit volume of air to the concentration of negative ions in the same volume of air, setting, for example, a predetermined concentration of ions of negative polarity using potentiometers 7 (preliminary) and 11 (finally), using a potentiometer 13 set such a concentration of positive ions that allows you to get a given coefficient of unipolarity of ions. The current Sanitary Standards allow the value of the coefficient of unipolarity of ions in the air of the living room from k = 0.4 to k = 1.0.

The circuit of the bipolar ion generator of FIG. 1 is constructed in such a way that, as described above, the corona electrodes 37 always participate in the formation of only negative ions, and the corona electrodes 43 only in the formation of positive ions. But the physical and chemical processes at these electrodes proceed in different ways. At negative high-voltage pulses, the corona electrodes 37 emit electrons into space, which, adhering to certain molecules and atoms of the air, for example, oxygen or water vapor, form negative ions. At the same time, these electrodes attract positive ions, for example, carbon dioxide, nitrogen compounds, from the air blown past them.

When applying high-voltage pulses to them, the corona electrodes 43 tear electrons from some molecules of the air blown past them, converting these molecules into primary positive ions and absorbing the electrons and some negative ions from the air blown past them.

As a result of these processes, the corona electrodes 37 and 43 wear and clog differently. As a rule, the corona electrodes that create negative ions wear out faster, and the corona electrodes that create positive ions clog faster, as if “fouling” with some kind of “pile”. This, of course, reduces the reliability and durability of these electrodes.

To reduce the negative impact of these effects and extend the life of the corona electrodes, using the timer 46 (Fig. 3), at regular intervals, turn on and off the electromagnetic relay 44, which with its contacts 47 and 48 switches the connection points of the output ends of the primary windings 33 and 40, respectively, of transformers 34 and 41. These switches create the same conditions for the operation of the corona electrodes 37 and 43, which alternately change the polarity of the ions they create. In this way, the time of stable operation of the electrodes and the ion generator as a whole is extended.

Since the description of the method of ionizing air describes the principle of operation of individual nodes and the ion generator as a whole, it makes no sense to give a separate description of the principle of operation of the bipolar ion generator. And although the sources of information referenced in the text describe in detail the operation of all the nodes used in the ion generator, it should be noted here for some details the operation of the pulse shaper 8 and voltage switches with three states at the output 15 and 26.

In the pulse shaper 8, assembled on the basis of the EXCLUSIVE OR logic element 9, the property of the logic element 9 is used to have a “zero” signal at the output if the signals are identical at both its inputs, i.e. either “zeros” or “ones”. If the signals at the inputs are different, i.e. on one input is “one” and on the other is “zero”, then a single signal will appear at the output of element 9. Therefore, when the “single” signal And ₁ arrives at the input of the pulse shaper from the output of the multivibrator 1, the first input of element 9 is under the “single” voltage, and the second input is under the “zero” voltage of the discharged time-setting capacitor 10, and immediately at the output of the element 9 the pulse And ₈ will be formed along the leading edge of the pulse And ₁ . Its duration will be determined by the time constant of the series-connected internal resistance of the open diode 12 plus the resistance of the potentiometer 11 and the capacitance of the capacitor 10, as well as the threshold of the element 9, which from element to element can take values from 0.4 to 0.7 of the supply voltage AND ₁₈ . By adjusting the resistance value of the potentiometer 11, the charge speed of the capacitor 10 and, thus, the duration of the pulse And ₈ formed along the leading edge of the pulse And _{1 are} changed. After the end of pulse And _{1, the} first input of element 9 will be under the "zero" potential, and the second input will be under the "unit" potential of the charged capacitor 10. At the output of element 9, a "single" pulse immediately appears along the trailing edge of the pulse And ₁ . This pulse will be present until the capacitor 10 is discharged to the response level of element 9. This discharge will flow through the potentiometer 13 and the internal resistance of the open diode 14. It is therefore clear that by changing the resistance of the potentiometer 13 the duration of the pulses And ₈ formed on the trailing edge of the pulses And ₁ . As a rule, the And ₈ pulse duration is an order of magnitude less than the And ₁ pulse duration at the maximum pulse repetition rate And ₈ Separated by means of diodes 12 and 14 of the charge and discharge circuits of the capacitor 10 allows independent control of the duration of And ₈ pulses generated along the front and rear fronts of pulses And ₁ .

The voltage switches 15 and 26 are assembled on the same type of elements, but with different points of connection of the outputs of the inverters 21 and 31. Due to this, the switch 15 is translated into the third state by a “single” pulse And ₈ coming from the output of the pulse shaper 8, which is fed to the first input of the element 2OR-NOT ”19 and translates it into a“ zero ”state at the output, due to which the transistor 16 is locked. The same pulse And ₈ through the inverter 21 in the form of a "zero" signal is fed to the second input of the 2I-NOT 20 element and puts its output in the "single" state, which leads to the locking of the transistor 17. Thus, in the third state, the output of the switch 15 is isolated from the supply bus 18 and the common bus by the large internal resistance of the locked transistors 16 and 17. Moreover, the switch 15 in the third state does not respond to a change in the signal at its signal input. When the And ₈ pulse goes to the “zero” state, the blocking is removed from the inputs of the elements 19 and 20, and the switch 15 turns into an inverter of And ₁ pulses arriving at its signal input.

The switch 26 operates as described, but it is transferred to the third state by a "zero" signal from the output of the pulse shaper 8.

And a few words about the corona electrodes 37 and 43. Although these electrodes are located nearby in the common duct 36, they do not affect each other's operation, since high-voltage pulses are not supplied to them simultaneously. Ions of different polarity formed by these electrodes are almost immediately mixed by an air stream.

Claims (4)

1. The method of ionization of air, in which air is passed through a system of corona electrodes installed in the blown air duct, to which alternating voltage pulses are supplied, the amplitude of which in both half periods is higher than the corona threshold, characterized in that the corona electrode system is made of two identical and adjacent groups electrodes, high-voltage pulses select by polarity and direct pulses of different polarity to different groups of corona electrodes, and the ion concentration and coefficient ient unipolarity ions is adjusted by independently changing the pulse duration of the positive and negative polarity. 2. The method of ionization of air according to claim 1, characterized in that at equal intervals of time the polarity of the high-voltage pulses supplied to different groups of corona electrodes is changed. 3. A bipolar ion generator containing a group of corona electrodes located in the blown air duct connected to the output winding of a high voltage transformer, the primary winding of which with a voltage boost capacitor connected in series with it, is included in the diagonal of the voltage bridge switch connected to the positive and common power buses, in which the first half of the switch is configured as a complementary emitter follower, and an ion concentration control unit, characterized in I mean that it is equipped with a third switch connected to the positive and common power buses, a second group of corona electrodes identical to the first group and located next to it, two diodes and a second high-voltage transformer, the output winding of which is connected to the second group of corona electrodes, the primary winding is turned on parallel to the primary winding of the first transformer, and both of these windings are connected to the output of the second switch through counter-connected diodes, moreover, both transformers are connected si phase, and the ion concentration control unit is made of a series-connected multivibrator with an adjustable pulse repetition rate and a pulse shaper, executed on the EXCLUSIVE OR logic element, the first input of which is connected to the output of the multivibrator, is also connected through two parallel-connected circuits consisting of in series connected potentiometers and diodes with on-switching, the second input of the logic element, to which is additionally connected connected to a common bus time giving a capacitor, the signal inputs of three voltage switches are connected either to one or to different outputs of the multivibrator, and the second and third voltage switches are made according to the scheme with three states at the output, in which the control inputs of the "third" state are combined and connected to the output of the pulse shaper, at the same time, the second switch is transferred to the "third" state by a "zero" signal, and the third switch - by a "single" signal. 4. The bipolar ion generator according to claim 3, characterized in that it is equipped with a timer with a pulse duty of two and an electromagnetic relay with two groups of changeover contacts, which is the load of the timer, and the contact groups of the relay are connected between the diodes and the primary transformer windings.

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