JP2008171785A - Corona discharge generation device by computer control - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a corona discharge generation device which is light and small with a structure of a limited number of simple electric components. <P>SOLUTION: A constant voltage power source is generated from a commercial power source and a pulse modulation is made a means by a computer circuit configuration. An adjustment of a corona discharge amount can be made by using a pulse width modulation (PWM) and a pulse position modulation (PPM). The device can be made small and light with the CPU circuit configuration and can be installed together with other electric devices. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a corona discharge apparatus and method efficiently and miniaturized by a computer (CPU) program.

  In recent years, bad odor due to environmental pollution has been noticeably increasing in the surrounding area. On the other hand, bad odors in hand-washing rooms have been eliminated immediately after use due to the development of new technology by toilet manufacturers. However, there is no way to easily eliminate the bad odors in places other than the washroom in ordinary households and public facilities.

Ozone (O ₃ ) is generated in the air by corona discharge. Ozone has a deodorizing effect. Sanitary equipment manufacturer's toilet deodorizers have commercialized devices with deodorizing effect due to the generation of ozone. When a DC voltage is applied between two parallel plates placed in the atmosphere, a very small current flows. It is thought that ions ionized by cosmic rays (accidentally called ions) move under the action of an electric field between electrode plates.

  As the voltage V increases, the current I gradually increases, but when V exceeds a certain value, I becomes almost constant. While V is low, the number of ions absorbed by the anode also increases with an increase in V, but when V exceeds a certain value, the ion velocity is increased and ionization is actively performed. Discharge phenomenon occurs. In this state, the discharge is continued even if there is no accidental ion. Also called self-sustained discharge.

  In an equal electric field, the spark voltage is determined by the product of the atmospheric pressure p and the spark gap d. If there is a minimum spark voltage for each gas type and the spark gap d is assumed to be constant, the chance of collision of moving electrons is reduced when p is too small. In addition, when p is excessive, a sufficient speed cannot be obtained, and in either case, the ionization action is not sufficiently performed.

  When the electric field between the electrodes is extremely non-uniform, local discharge occurs in a portion where the electric field is large. This is called corona discharge. For example, the DC voltage applied between the flat plate electrode and the needle electrode is gradually increased, and when a certain voltage is reached, a light purple light spot appears at the end of the needle. This is called glow discharge. When the voltage is increased, a corona with a long shape is generated.

  On the other hand, negative ion generators include corona discharge method, electron emission method, plasma, Leonard method, use of natural ore (for example, Tolman ore), charcoal, bamboo charcoal and the like. All three are aimed at ionizing the atmosphere due to discharge. Many proposed negative ion generators use a discharge phenomenon. If the second electrode is installed, ozone is generated by corona discharge together with negative ions. Ozone has a deodorizing effect.

  The discharge sustaining devices used in negative ion generators are often corona discharge and creeping discharge. A corona discharge is a continuous discharge that occurs when a non-uniform electric field is generated around a pointed electrode (needle electrode).

The present invention provides a small, lightweight and inexpensive apparatus using program control by a CPU (central processing unit) so that ozone by corona discharge is efficiently diffused into the atmosphere.
JP 2005-094827 Japanese Patent Fair 11-060759

  One of the problems to be solved is to provide an ozone generator by corona discharge regardless of the installation location and special equipment. If the device is reduced in size and weight, the device according to the present invention can be attached to household devices and portable devices. Ozone can be diffused efficiently from these devices.

  It is effective if this apparatus is installed indoors or in a public place to prevent bad odors, or an ozone generator is added to other equipment such as a ventilation fan, a lighting fixture, an air conditioner, a hot air stove, a flashlight. Placing equipment that incorporates an ozone generator in the bathroom, toilet, kitchen, or room creates a deodorizing effect and cleans the room.

  In order to solve the above problems, the present invention can adjust the amount of corona discharge generated by program control using an inexpensive CPU. Control is performed by combining PWM (pulse width modulation) and PPM (pulse position modulation) efficiently. The high voltage can be freely changed by a boosting high-frequency transformer in the subsequent stage. A capacitor that reduces noise and reduces ripple is provided on the output side to efficiently generate corona discharge.

  Since it can be reduced in size and weight, it can be used effectively because it can be installed in household appliances and part of public facilities and does not take up space. Since the object can be achieved by a simple combination of a CPU, a high-frequency transformer, and a noise removing capacitor, it is highly convenient.

  The ozone generator by corona discharge according to the present invention is small, light and inexpensive, so it can be installed inside other equipment such as copiers, fax machines, printers, etc. in the office, or microwave ovens, refrigerators, washing machines as home appliances. It can be prepared for air conditioners. Ozone is generated and released efficiently in the air indoors. It can also be easily installed in public facilities such as hand-washing and toilets.

  As an example, if this apparatus is attached to a lighting fixture such as a light bulb, it can be easily installed in the kitchen, hand-washing, and toilet in the home. In public facilities, this device is attached to a hot air dryer installed in a hand-washing area, which is effective in removing unpleasant odors in the toilet. Furthermore, if it is installed in an outdoor advertising tower, lighting such as a show window, it will be effective in removing exhaust gas and pollution from diesel engines in the city.

BEST MODE FOR CARRYING OUT THE INVENTION

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  FIG. 1 is a block diagram showing an overall configuration according to the present invention. In the figure, reference numeral 11 denotes a commercial power source, which is generally AC 100 V, 50/60 Hz. Reference numeral 12 denotes a constant voltage power supply, also called a switching regulator. Reference numeral 13 denotes a control circuit including a CPU. Here, PWM and PPM signals for corona discharge control are generated. The output of this circuit unit is a high-frequency pulse train.

  Reference numeral 14 denotes a high-frequency voltage circuit unit modulated by 13. A high frequency transformer 15 generates a high voltage of several KV. Reference numeral 16 denotes a rectifier circuit that rectifies 15 high-voltage output voltages. A rectifier diode or thyristor (AC control element) for withstand voltage is used. Reference numeral 17 denotes a capacitor circuit which uses a high breakdown voltage capacitor. This circuit portion functions as a smoothing circuit for causing corona discharge and a noise limiter for preventing noise from being generated around the circuit. Ceramic capacitors and tantalum capacitors are mainly used.

  Reference numeral 18 denotes an electrode of a corona discharge emitting portion, and 19 denotes a corona. At this time, ozone is emitted into the atmosphere. 20 is an electrode, 21 is a ground and earth. When there are no 20 electrodes, corona discharge is not performed. Ions diffuse into the atmosphere. For example, if you want to switch between negative ion release and corona discharge. A switch is provided between 20 and 21, and a switching signal may be issued from 13 CPU circuits as necessary.

  Reference numeral 22 denotes an electric lamp illumination circuit. In the present invention, 22 and 23 may be omitted if not necessary. Reference numeral 23 denotes a light bulb. When the light bulb 23 is a fluorescent lamp or a cold cathode tube, the light can be adjusted to a desired brightness by inputting a modulated signal wave from the CPU circuit 13. Reference numeral 24 denotes an external switch for controlling a corona discharge amount, that is, an ozone generation amount. The dimming of 23 can be performed from 24 switches. The external switch 24 changes the modulation width of the PPM and PWM by changing the CPU program from the outside. The amount of 18 corona discharges can be adjusted.

  FIG. 2 is a block diagram showing details of the computer control circuit unit 13 and its peripheral parts. In the figure, 31 is an internal bus, and 32 is a CPU and a central processing unit. 33 is a ROM which is a program memory, and 34 is a RAM. A memory 35 temporarily stores data obtained by arithmetic processing of the CPU 32, external sensor data, and the like. Depending on the application of a part of this memory, it is possible to store the optimum value of the discharge device in a non-volatile memory so that a good output is always obtained.

  Reference numerals 36 to 39 denote interface units between the computer circuit and the outside. Reference numeral 36 denotes an I / O1, which is an input port to the computer circuit unit. The external switches 40 and 41 are connected. Both 40 and 41 are switches for changing the discharge amount 19. For example, 40 changes the PWM modulation by a program of the CPU 32, and 41 changes the amount of ozone of 19 by changing the modulation degree of PPM.

  Reference numeral 38 denotes an output port I / O3 from the computer circuit section. The external switch 42 and the illuminance sensor 45 are connected. The program of 42 switch CPU32 is changed and the brightness of 23 illumination lamps is changed. A sensor 45 inputs the brightness, and mainly uses a phototransistor. The user can be dimmed by 42 switches.

  Reference numeral 39 denotes an output port I / O4. A dimming signal is sent to the 22 lamp lighting circuit. As described above, in the case of an incandescent lamp, a fluorescent lamp, a cold cathode tube, an LED (light emitting diode), etc., the lamp can be dimmed to a desired brightness from the CPU 32 by PPM and PWM modulation. The user can operate with 42 switches.

  37 I / O2 is an output port, and sends high frequency pulses to 43 in 46 external component parts. This high frequency pulse is a pulse modulated by PPM and PWM. Reference numeral 44 denotes an inverter circuit unit which converts it into alternating current in synchronization with the high frequency pulse 43. 14 in FIG. 1 corresponds to 43 and 44 in FIG. The high frequency AC wave output from 44 is boosted to several KV by 15 high frequency transformers.

  After passing through 16 rectifier circuits and 17 capacitor circuit sections, corona discharge is generated at 18 electrodes, and 19 corona is released into the atmosphere as ozone. The computer circuit unit of FIG. 2 is characterized in that the corona discharge amount is controlled by PPM and PWM control, and can be adjusted by the user with the external switches 40 and 41.

  FIG. 3 is a diagram illustrating the behavior of corona discharge. In FIG. 3A, the DC voltage applied between the plate electrode 54 and the needle electrode 52 is gradually increased, and when a certain voltage is reached, a light purple light spot such as 53 appears at the end of the needle. This is called glow corona. Reference numeral 51 denotes a high voltage HV1, and reference numeral 55 denotes an earth and a ground.

  In FIG. 3B, when the voltage of 56 is further increased, a corona having a shape extending long like 57 is generated. This is called brush corona. When the voltage is further increased as indicated by 58, a corona 59 in which many streaks of thin light straddling the electrodes appear as shown in FIG. 3C. This is called Hokko Corona. When a high frequency high voltage is applied instead of direct current, a corona corresponding to the polarity is generated every half cycle.

  FIG. 4 shows a PPM pulse train generated by the CPU circuit unit. In the figure, 61 ml to 61 mn indicate pulse trains. PPM is a modulation method in which the pulse width is constant and the interval is continuously changed. FIG. 4A shows a pulse train, and t1, t2, t3, and tmn are pulse intervals, and these intervals continuously change depending on the modulation signal. In the figure, three pulses of tf1 are shown as an example, and the interval of t1 = t2 = t3 is constant. When this pulse interval is continuously changed, PWM modulation can be performed.

  At tf2, it is a continuous pulse train, and the pulse interval changes continuously depending on the modulation degree. The pulse is continuously variable, the high frequency signal of the output is changed, and the high voltage output voltage is also appropriately changed. The change in the output voltage is as shown in the explanatory diagram of the principle of corona discharge in FIG. V01 is the pulse peak value.

  FIG. 4B is a schematic diagram of a high voltage applied to the electrode. 62m1, 62m2, 62m3, and 62m4 are drawn symmetrically to the pulse train 61 in FIG. tf1 is an equidistant pulse train, and here, a continuous modulated wave is not drawn for easy explanation. Vp1 is an output stage generated by an equidistant pulse train between tf1, and is a peak value of a high voltage. t1 ', t'2, t'3, and t'mn are symmetrical with t1, t2, t3, and tmn in FIG.

  Va1 is a smoothed high voltage value of the output stage. This Va1 contributes to the occurrence of corona discharge. The smoothing high voltage depends on the capacity and characteristics of the capacitor circuit. Therefore, Va1 increases as the capacitance of the capacitor increases. However, the capacitor itself becomes large, and the circuit portion is not miniaturized. The value of the capacitor is determined in consideration of this balance. If the high frequency, that is, the interval between t'1, t'2, t'3, and t'mn is shortened, the values of Vp1 and Va1 change. That is, the output voltage can be changed by continuously variable PPM control. As a result, the amount of corona discharge is changed, and the amount of ozone generated can be controlled.

  FIG. 4C shows the relationship between the smoothing high voltage Va1 and the corona generation amount cd. As Va1 is increased, corona discharge occurs. As Va1 is further increased, the corona generation curve cdx increases. When it is further raised, spark discharge and arc discharge finally occur and corona is not generated. Cda indicates this. That is, Va1 contributing to the generation of corona discharge can be controlled by the value of the PPM modulation and the capacitor circuit.

  FIG. 5 shows a control method of the corona discharge amount by the PWM and pulse width modulation method. FIG. 5A shows a schematic diagram of a PWM control pulse train. 65m1 to 65m4 indicate the state of pulse width modulation of the pulse. In the figure, the pulse width is w1> tw2> tw3 <tw4. The pulse period t1 = t2 = t3, and so on. Vo2 is the peak value of the pulse.

FIG. 5B shows voltages Vp2 and Va2 applied to the high voltage output stage 18 in FIGS. 66m1, 66m2, 66m3, and 66m4 correspond to 65m in FIG. The period t0 is constant here. A pulse period t1~tmn = _{t 0} in FIG. 5 (a). It is also possible to add PPM pulse period modulation to this PWM modulation. Finer control can be performed by the CPU program of FIG.

  When it is desired to finely change the amount of ozone generated, the amount of ozone generated can be changed by appropriately adding the PPM and PWM disclosed in this proposal to the pulse train or by alternately changing the corona discharge value.

  FIG. 5C is a characteristic curve showing the relationship between the corona discharge amount and the applied high voltage Va2. Cd is the amount of corona discharge, and Cdy is the corona discharge generation characteristic curve. When Va2 is increased, arc spark discharge is generated as in FIG. 4C, resulting in Cda, and corona discharge is stopped. Therefore, ozone is not generated. Therefore, even if the smoothed high voltage Va2 is increased, there is a limit, and corona discharge occurs in an appropriate applied voltage range. Vp2 in FIG. 5B is a peak value for the high voltage ripple, and is related to the smoothing value Va2.

  FIG. 6 is a flowchart showing an example of controlling the corona voltage and the ozone discharge amount by the PPM / PWM control method of the present invention. In FIG. 6, S601 determines whether ozone is generated or the lamp is lit based on signals input from the external switches 40, 41, and 42 shown in FIG. In step S602, it is selected whether to turn on only the lamp, only corona discharge, or both.

  In step S603, it is determined whether only corona discharge is turned on. In S604, both the corona discharge and the electric lamp are turned on. If the lamp is selected to be off in S602, only corona discharge is turned on in S604. In S605, the amount of corona discharge, that is, the amount of ozone generated is adjusted according to the user's preference. This is adjusted by 40 and 41 external switches.

  The user can control the amount of ozone generated by adjusting the switches 40 and 41 according to his / her preference. S606 is a routine for determining the amount of corona discharge, and can actually be varied linearly by the switches 40 and 41. Here, large, medium, and small are used for ease of explanation, but such steps may be used depending on the application. In S607, the discharge amount was set to the maximum. The high voltage applied to the electrode 18 in FIG. 1 is set to the maximum value of the amount of corona discharge.

  In S608, the applied voltage is determined. In step S609, the modulation method, PPM, and PWM are selected. This is done by operating the switch means 40, 41. From the experimental values, PWM can be selected by the user as long as it can be determined that, for example, corona discharge roughly or PPM is suitable for fine control. Further, a switch 40y (not shown) for selecting both PPM and PWM may be provided. In this way, fine control is possible by the combination of PPM and PWM.

  S610 was determined to be pulse width control and PWM. In S611, PWM is continuously modulated, and the ozone selected by the user is released. In S612, the user has selected pulse position modulation and PPM. In S613, continuous PPM modulation is performed to obtain the ozone generation amount directed by the user.

  In S619, it is checked whether the switch is turned off. If the switches 40, 41, and 40y are turned off, the corona discharge is stopped. In S614, the lamp is not turned on. Therefore, only corona discharge. In step S620, only the lamp is lit without performing corona discharge. In step S621, the brightness of the lamp is adjusted. The modulation is performed by the CPU, PPM, and PWM. Since the commercial power source is converted to a high frequency power source, the brightness can be adjusted smoothly.

  The brightness of the lamp is set by the user from the switch 42 in FIG. 2, but the brightness can be adjusted to a desired brightness by inputting the output light from the 45 photosensor, and the brightness is constant even if the power supply voltage fluctuates. I can keep it. Unaffected by power fluctuations. Urban commercial power supplies consume large amounts and vary a lot, so the power supply voltage is often below a certain voltage. According to this proposal, even if the input voltage varies, there is an effect that the illuminance of the corona discharge and the lamp can be kept constant by PPM and PWM modulation.

  In step S615, it is checked whether the discharge amount is selected to be medium. In S616, the discharge amount is set to medium. In S617, it is checked whether or not the discharge amount is set to a small level, and in S618, the modulation is controlled so as to reduce the discharge amount. In S617, if the corona generation amount is not selected to be small, control is performed with an appropriate value from data in the CPU program.

  The control method of the ozone generation amount according to the present plan is that if an appropriate capacitor capacity is provided in the output stage and PPM and PWM modulation are combined, fine adjustment and stable corona discharge are generated, and stable ozone in the atmosphere. Can be released. Capacitors are small and function well as noise limiters. Therefore, it can be reduced in size and weight and can be achieved at low cost.

  It can be attached to lighting, home appliances, and communication equipment in places that emit a strange odor inside the house. Convenience is also good because it can be attached to other devices in public facilities as well. Corona discharge also occurs in high voltage pulse power supplies. However, it occurs intermittently instantaneously. This is effective, but it generates unwanted secondary radiation and does not pass the safety standards for electrical equipment.

  As in this proposal, simply by placing a capacitor for limiting the noise secondary emission at the output end, the corona discharge can be stably generated and the noise generation can be suppressed, and the emission of ozone can be controlled stably.

  It is a block diagram which shows the structure of this embodiment.   It is a block diagram which shows a CPU control circuit.   It is a schematic diagram of corona discharge.   It is a figure which shows a pulse position modulation and a PPM modulation system.   It is a figure which shows a pulse width modulation and a PWM modulation system.   It is a flowchart which shows the structure and execution of this plan.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Commercial power supply 12 Constant voltage circuit part, Switched regulator 13 CPU circuit part, Computer control part 14 High frequency voltage circuit part 15 High frequency transformer, step-up transformer 16 Rectifier circuit part 17 Capacitor circuit part, smoothing circuit part 18 Tip electrode 19 Corona discharge 20 electrode, flat plate electrode 21, 55 earth, ground 22 radiation negative ion 23 lamp, light bulb 24, 40, 41 corona discharge amount adjustment switch 31 system bus 32 CPU, central processing unit 33 ROM, program memory 34 RAM, random access memory 35 Memory, nonvolatile memory 36, 37, 38, 39 I / O section, input / output section 42 Illuminance adjustment switch 43 High frequency pulse 44 Inverter circuit section 45 Photo sensor 46 External component units 51, 56, 58 High voltage power supply 52 Tip electrode, needle Electrodes 53 and 5 , 59 Corona discharge 54 plate electrodes, electrodes 61 and 65 pulse train 62, 66 high voltage output value

Claims (5)

A configuration in which a pulse train is generated by a program using a central processing unit (CPU) by inputting from a commercial power source and leading to a constant voltage, and the pulse is input to an inverter, and a high-frequency transformer, a rectifier circuit unit, and a smoothing circuit In the configuration to obtain a high voltage with the part
An apparatus comprising an output side electrode and a receiving side electrode, applying the high voltage to one electrode and providing a grounded electrode at the other end to generate a corona discharge,
Means for obtaining a high voltage by pulse train modulation for the purpose of generating a high-voltage power supply;
The pulse train means uses pulse width modulation (PWM) and pulse position modulation (PPM) means. A computer controlled corona discharge generator. 2. The computer control according to claim 1, wherein the pulse modulation is provided with input means from an external switch, and the degree of pulse modulation can be varied by operating the switch, and the amount of corona discharge can be adjusted. Corona discharge generator. The above-described pulse modulation achieves the object by using pulse width modulation, pal width modulation, and both methods in accordance with the degree of corona discharge amount control. A capacitor for removing noise is connected to the high-voltage output power source according to claim 1 applied to the tip electrode, and the capacitor is a means having an appropriate capacity for sustaining corona discharge. A computer-controlled corona discharge generator. 5. The computer-controlled corona discharge generator according to claim 4, wherein the capacitor is determined in association with the degree of pulse modulation, and is extremely small and lightweight.

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