JP2015207410A - ion generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a discharge state from being unstable in an ion generator, which generates ions through an aerial discharge from a discharge electrode by applying high-voltage electricity, as capacitance contributing a cable supplying the high-voltage electricity affects the discharge when the cable becomes long, and to prevent an unnecessary discharge from being caused after the ion generator stops operating to generate noise.SOLUTION: An electric resistor 51 for discharging electricity accumulated in a cable 3 is installed, and then has one end connected to a discharge electrode 4 and the other grounded. Further, the electric resistor 51 has its resistance value determined according to characteristics of a high-voltage electricity generation circuit 2, a structure of the discharge electrode 4a, and material characteristics of an insulator film 3b covering the cable 3.

Description

  The present invention relates to an ion generator in which a high-voltage electricity generation circuit and a discharge electrode are separately installed.

  The ion generator which this invention makes object produces | generates ion from the gas molecule in air by outputting the output voltage of a high voltage | pressure electricity generation circuit to a discharge electrode, and making it discharge in air | atmosphere. A high voltage electricity generation circuit for generating ions and a discharge electrode for generating ions are connected by an electric wire, and high voltage electricity is supplied to the discharge electrode. Since the high-voltage electricity supplied is from several kV to several tens of kV, an electric wire in which the periphery of the conductor core wire is covered with a withstand voltage insulating film is used. Insulating coatings have not only the positive side of preventing high-voltage electricity from leaking, but also the negative side of exhibiting a parasitic capacitance of the size inherent to the insulating material. Capacity also increases.

  This electric parasitic capacitance accumulates high-voltage electricity supplied through the conductor, which also affects the voltage waveform applied to the discharge electrode, especially when the wire length is several centimeters or more and high-voltage electricity is given as a pulse. The waveform is deformed.

  When the generation of high-voltage electricity is stopped to stop the operation of the ion generator, the high-voltage electricity remains accumulated in the insulating coating. For this reason, there is a problem that an unnecessary discharge phenomenon continues even though the operation is stopped. If the electric parasitic capacitance between the high-voltage electricity generation circuit and the discharge electrode is sufficiently small, the amount of charge accumulated on the electrode is small, so the discharge time of the residual charge is shortened and the charge accumulation is eliminated immediately after the high-voltage circuit stops operating. However, if the electric parasitic capacitance increases, unnecessary discharge continues for a long time.

  In response to such an unnecessary discharge phenomenon, Japanese Patent Application Laid-Open No. 09-310668 (Patent Document 1) discloses a method for eliminating unnecessary discharge of an ignition device used in a vehicle engine.

JP 09-310668 A

  However, the above-mentioned patent document relates to ignition of an internal combustion engine, and is intended to quickly discharge the charge charged to the insulating coating after satisfying the ignition condition by applying a pulse voltage to the discharge electrode. Not suitable for ion generators. That is, in order for the ion generator to maintain the ion generation at an appropriate ion concentration, it is important that the discharge is continued at the discharge electrode, and even when a pulse voltage is applied, an electrode having a voltage higher than the discharge voltage is required. The voltage must be maintained for a certain period. On the other hand, it is preferable to quickly remove unnecessary charging when voltage application is completed.

  For this purpose, it is necessary to install a discharge resistor that can maintain both an appropriate discharge voltage and an appropriate charge removal time. From this, it depends on the distance between the electrodes of the discharge electrode and the parasitic capacitance of the cable. It is necessary to set the earth resistance. A method that aims only at quickly discharging electric charges as in the above-mentioned patent document is inconvenient.

  Accordingly, the present invention provides an ion generator in which a high-voltage electricity generation circuit and a discharge electrode to which the high-voltage electricity generation circuit is provided are spaced apart from each other, so that an appropriate ion concentration is obtained and the remaining charge is discharged immediately after the operation is stopped. It is an object of the present invention to provide an ion generator having a ground resistance having an appropriate resistance value for preventing an excessive discharge.

  An ion generator according to the present invention has a shielded cable connecting a high-voltage electricity generation circuit including a booster circuit and a discharge electrode, the shield is grounded, and the discharge electrode and the shield are connected by a ground resistance. It is characterized by doing.

  Further, an ion generator according to the present invention has a shielded cable connecting a high-voltage electricity generation circuit including a booster circuit and a discharge electrode, the shield is grounded, and further has a counter electrode connected to the shield. In addition to being provided in the vicinity of the discharge electrode, the discharge electrode and the shield are connected by a ground resistance.

  In addition, an ion generator according to the present invention has a shielded cable connecting a high-voltage electricity generation circuit including a booster circuit and a discharge electrode, the shield is grounded, and further, an output end of the high-voltage electricity generation circuit The shield is connected with a grounding resistor.

  The ion generator according to the present invention includes a shielded cable connecting a high-voltage electricity generation circuit including a booster circuit and a discharge electrode, and the shield is grounded, and further in the middle of the cable, the cable The electric wire and the shield are connected with a grounding resistance.

  Further, in another ion generator according to the present invention, the ground resistance is 3 GΩ (gigaohm) or more and 9.6 GΩ or less.

  According to the present invention, in an ion generator in which a high-voltage electricity generation circuit and a discharge electrode are provided apart from each other and connected between them with an insulation-coated cable, ions are generated at a stable ion concentration without being affected by the length of the cable. It is possible to provide an ion generator that is generated and does not cause unnecessary discharge after the operation is stopped.

It is the schematic which shows the structure of the ion generator which concerns on Embodiment 1 of this invention. It is the schematic which shows the structure of the ion generator for a comparison of this invention. It is a noise pressure graph in the negative discharge electrode of the ion generator for a comparison. It is a noise pressure graph in the positive discharge electrode of the ion generator for a comparison. It is a noise pressure graph in the negative discharge electrode of the ion generator of Embodiment 1 of the present invention. It is a noise pressure graph in the positive discharge electrode of the ion generator of Embodiment 1 of the present invention. In the ion generator of Embodiment 1 of this invention, it is a graph which compares the electrode voltage in the steady operation when the earth resistance is 3 GΩ and 6 GΩ. It is a transformer output waveform in case earth resistance is connected to the discharge electrode of the ion generator of Embodiment 1 of the present invention. It is a transformer output waveform in case earth resistance is not connected to the discharge electrode of the ion generator of Embodiment 1 of this invention. It is a schematic top view of the board | substrate mounting example of the earth resistance which concerns on Embodiment 1 of this invention, and is a figure of a board | substrate pattern surface. It is an external appearance schematic diagram of the ion generator of Embodiment 1 of this invention. It is the schematic which shows the structure of the ion generator which concerns on Embodiment 2 of this invention. It is a schematic plan view of the board | substrate mounting example of the electrode assembly which concerns on Embodiment 2 of this invention, and is a figure which shows a board | substrate pattern surface. It is a figure which shows the bottom view of the mounting substrate of FIG. It is a schematic diagram which shows the structure of the ion generator which concerns on Embodiment 3 of this invention. It is a schematic plan view of the board | substrate mounting example of the electrode assembly which concerns on Embodiment 3 of this invention, and is a figure of a board | substrate pattern surface. It is an external appearance schematic diagram of the ion generator which concerns on Embodiment 4 of this invention. It is the schematic which shows the structure of the ion generator which concerns on Embodiment 5 of this invention. It is a schematic top view of the board | substrate mounting example of the high voltage generation circuit which concerns on Embodiment 5 of this invention, and is a figure which shows a board | substrate pattern surface.

  Hereinafter, an example of an embodiment of the present invention will be specifically described with reference to the drawings. In each of the drawings to be referred to, the same part is denoted by the same reference numeral, and redundant description regarding the same part is omitted in principle. In this specification, for simplification of description, a symbol or reference that refers to information, signal, physical quantity, state quantity, member, or the like is written to indicate information, signal, physical quantity, state quantity or Names of members and the like may be omitted or abbreviated.

(Embodiment 1)
In FIG. 1, the schematic block diagram of the ion generator 1 which concerns on Embodiment 1 is shown. The ion generator 1 includes a high voltage generation circuit 2 that generates high voltage electricity, a cable 3 that supplies high voltage electricity generated by the high voltage generation circuit 2 to a discharge electrode, and a high voltage electricity supply that discharges in the air to generate ions. And an earth resistor 5 for connecting the core of the cable 3 and the shield.

  In the ion generator 1, the electrode assembly 4 is provided 35 cm away from the high voltage generation circuit 2, and the high voltage generation circuit 2 and the electrode assembly 4 are connected by the cable 3. The cable 3 is configured such that the outer side of the high-voltage potential line 3a, which is a core wire, is surrounded by an insulating coating 3b, and the outer side is covered with a shield 3c made of a conductor. The output of the high voltage generation circuit 2 is supplied to the discharge electrode 4 a of the electrode assembly 4 via the high voltage potential line 3 a of the cable 3. The shield 3c of the cable 3 is connected to the ground line of the high voltage generation circuit 2 and shares the ground.

  The electrode assembly 4 includes a discharge electrode 4a and a counter electrode 4b facing the discharge electrode 4a. The discharge electrode 4a is a needle-like metal rod. The counter electrode 4b is formed by bending a perforated metal plate into an L shape. The counter electrode 4b is positioned so as to be a circular hole centered on the tip of the discharge electrode 4a, and is fixed in the vicinity of the discharge electrode 4a. Yes. The discharge electrode 4a discharges the high voltage electricity supplied from the high voltage generation circuit 2 from the needle-shaped tip toward the air, and the counter electrode 4b collects the electricity discharged by the discharge electrode 4a to stabilize the discharge. do. One end of the shield 3c is connected to the counter electrode 4b of the electrode assembly 4, and the other end is connected to the ground line of the high voltage generation circuit 2 and grounded. That is, the shield 3c serves as a conductive wire having a ground potential.

  The ground resistor 5 has one end connected to the high voltage potential line 3a of the cable 3 and the other end connected to the shield 3c. In the present embodiment, the earth resistor 5 is inserted and installed in the middle of the cable 3. The earth resistor 5 is grounded via the shield 3c.

  The high voltage generation circuit 2 includes a booster, and outputs a DC voltage including a pulse voltage by rectifying the output with a diode. This DC voltage can be applied to the needle-like discharge electrode 4a of the electrode assembly 4 to start discharge, and has a voltage high enough to generate ions continuously. In the high voltage generation circuit 2, one of the output terminals is used as a high voltage output terminal, and the other terminal is grounded to serve as a ground line.

  In the ion generator 1 of the present embodiment, the discharge electrode 4a is a positive discharge electrode that generates positive ions upon receiving a positive DC voltage from a rectifier circuit connected to the output terminal of the high voltage generation circuit 2, or a rectifier circuit. The negative discharge electrode that receives a negative DC voltage from the negative electrode and generates negative ions is used as one of the negative discharge electrodes.

  FIG. 2 is a schematic diagram illustrating a configuration of a comparative ion generator 100 in which the earth resistor 5 is removed from the ion generator 1 according to the first embodiment. The cable 3 shown in FIG. 1 and FIG. 2 has a high-voltage potential wire 3a, which is a core wire through which electricity flows, is covered with an insulating coating 3b, and the outside of the insulating coating is further covered with a shield 3c made of a braided conductor. In this structure, a dielectric effect according to the physical properties of the insulating coating material is generated by energization, and since the structure is homogeneous in the length direction, a capacitive component corresponding to the length of the cable is parasitic.

  In the ion generator 100 configured as described above, the generation of noise was observed after the ion generation period and ion generation was stopped. FIG. 3 is a noise pressure graph at the negative discharge electrode of the comparative ion generator 100 of FIG. The horizontal axis of the plot is time, the unit is second, and the vertical axis is sound pressure. In this noise pressure plot, the ion generator stops operating at about 0.09 seconds after the start of timing, but after about 0.02 seconds, noise equivalent to the operating noise is generated, and after the operation stops 0 Continues after 3 seconds.

  As shown in FIG. 4, even at the positive electrode, the ion generator stopped operating at about 0.05 seconds after starting timing, but about 0.02 seconds after that, noise equivalent to operating noise was generated and stopped. It continues even after 0.15 seconds. However, although the discharge sound after the operation stop can be confirmed at the positive electrode, the sound pressure level is lower and the duration is shorter than that of the negative electrode.

  5 and 6 are noise pressure graphs in the case of the ion generator 1 according to Embodiment 1 of the present invention. FIG. 5 shows noise generation in the negative electrode, and FIG. 6 shows noise generation in the positive electrode. In FIG. 5, no noise is generated after the operation of the ion generator 1 is stopped 0.09 seconds after the start of measurement. Similarly, in FIG. 6, no noise is generated after the operation of the ion generator 1 is stopped at 0.14 seconds after the start of measurement. Such noise generation is due to a discharge phenomenon caused by electric charges remaining on the discharge electrode and the cable, and can be explained as follows.

  The ion generator 1 and the comparative ion generator 100 of the present embodiment utilize corona discharge by high-voltage direct current electricity including a pulse voltage, and the space charge of positive ions is distributed in the vicinity of the electrode assembly 4. Affects the discharge conditions. When the polarity of the discharge electrode 4a is negative, the space charge of positive ions approaches the negative electrode due to the Coulomb force with the electrode, so that the electric field is strengthened, and the discharge continues even if the electrode potential decreases and the electric field decreases due to the discharge. . On the contrary, when the polarity of the discharge electrode 4a is positive, the space charge and the electrode have the same polarity and the distance from each other is also separated by the Coulomb force, so the electric field is weakened and the discharge does not continue as much as the negative electrode.

  In the case of a spark plug for a hydrogen engine for a vehicle disclosed in the prior art document, in order to remove the charge accumulated in the electrode and the cable connected thereto, the resistance value of the ground resistance R1 is set to 5 MΩ (mega ohms) and the residual charge is promptly Is going to be removed. In other words, in the case of the ignition plug of the internal combustion engine of the prior art document, the period during which the discharge is required is a voltage pulse width, which is very short and single, and is not ignited during the next intake stroke. The resistance value is selected so that the residual charge can be removed quickly in the exhaust stroke.

  In contrast, in the ion generator targeted by the present invention, the period in which the discharge is required is a voltage application period that is applied with a continuous pulse or a constant voltage, and the duration is long, and the discharge period is Although a high voltage must be maintained, it is necessary to quickly remove residual charges after the apparatus is stopped.

  The voltage of the discharge electrode 4a during the steady operation is balanced by a voltage at which the output current of the high voltage generation circuit 2 is equal to the sum of the discharge current of the discharge electrode 4a and the current flowing through the earth resistor 5. That is, the voltage has a relationship represented by the following formula (1). However, since the output current of the high voltage generation circuit 2 is small, if the resistance value of the ground resistor 5 is small, the discharge electrode 4a continues to discharge. Necessary discharge voltage cannot be obtained. Here, the following relational expression holds.

Iout = Element + Element / Radjust (1)
From equation (1)
Radjust = Element / (Iout-Element) (2)
Get.
In order to secure the discharge voltage of the discharge electrode, it is desirable that the resistance value of the ground resistor 5 is as large as possible while satisfying the relationship of the expression (2). Therefore, from equation (2)
Radjust ≧ Element / (Iout-Element) (3)
It becomes.
Here, Iout: the output current of the high voltage generation circuit 2, Ielement: the average discharge current of the discharge electrode, Element: the discharge voltage of the discharge electrode, and Radjust: the resistance value of the ground resistor 5.

On the other hand, the time required to discharge the residual charge when the operation is stopped is given by the following equation (4).
t = -1 * Radjust * Ccable * ln (1-V / V0) (4)
From equation (4)
Radjust = −t / (Ccable × ln (1−V / V0)) (5)
Get.
In order to discharge the residual charge in a short time, the resistance value of the ground resistor 5 should be as small as possible while satisfying the relationship of Expression (5). Therefore, from equation (5)
Radjust ≦ −t / (Ccab × ln (1−V / V0)) (6)
It becomes.
Here, Radjust: resistance value of the ground resistor 5, t: maximum allowable discharge time, Cable: electric parasitic capacitance of the cable 3, V: discharge electrode voltage at the time of discharge, V0: discharge electrode voltage at the start of the discharge , Ln (1-V / V0): natural logarithm with voltage as an argument.

Therefore, in order to obtain an optimum ion generator circuit, the relationship of the following equation (7) derived from the equations (3) and (6) may be satisfied.
Element / (Iout−Element) ≦ Radjust ≦ −t / (Ccab × ln (1−V / V0)) (7)

For example, when the voltage Velement of the discharge electrode 4a is 3 kV, the average output current Iout of the high voltage generation circuit 2 is 12 μA (microamperes), and the average discharge current Ielement of the discharge electrode 4a is 11 μA, the resistance value Radjust of the ground resistor 5 is From relational expression (3),
Radjust ≧ 3000V / (12 μA-11 μA) = 3 GΩ (8)
Get.

Further, when the maximum allowable discharge time t is 0.5 seconds, the discharge electrode voltage V0 at the start of discharge is 3 kV, the discharge electrode voltage V at the time of discharge is 2 kV, and the electric parasitic capacitance Ccable of the cable is 75 pF, From the relational expression (6), the resistance value Radjust of the grounding resistor 5 is
Radjust ≦ −0.5 / (75pF × ln (1-2000V / 3000V)) = 6.1 GΩ (9)
Get.

  Here, it considers considering the structure of a general electrode assembly. Generally, the discharge start voltage in the air is said to be about 1 kV with respect to the distance between the electrodes of 1 mm. That is, if the gap between the discharge electrode and the counter electrode is 1 mm, discharge is started and ions are generated when high voltage electricity of 1 kV is applied. However, if the total discharge time is increased by using an ion generator, suspended matters in the air adhere to the discharge electrodes and spherical foreign matters are generated, which not only hinders the discharge but also grows with time, and the space between the electrodes Will not be able to sustain the discharge.

  In order to extend the practical time, it is necessary to increase the gap between the discharge electrode and the counter electrode, but as the distance increases, the discharge start voltage increases, and not only the electrode assembly increases, but also the surroundings Since it is necessary to increase the insulation distance, the entire ion generator is enlarged. In a small ion generator for installation in equipment, this causes a great problem in terms of design flexibility and cost.

Considering such contradictory constraints, it is considered that the practical range is to set the gap between the discharge electrode and the counter electrode to about 2 mm to 10 mm. Substituting the discharge voltage 2 kV to 10 kV corresponding to this into the above equation (3),
For a voltage of 2 kV, 2 GΩ ≦ Radjust
For a voltage of 10 kV, 10 GΩ ≦ Radjust is obtained.

Further, the maximum allowable discharge time t is 0.5 seconds, the gap between the practical discharge electrode and the counter electrode is about 2 mm to 10 mm, and the corresponding discharge start voltage is 2 kV to 10 kV. When the discharge electrode voltage during discharge is 1 kV to 9 kV and the electric parasitic capacitance of the cable is 75 pF, the above equation (6) is substituted.
For voltage 2 kV, 9.6 GΩ ≧ Radjust
For a voltage of 10 kV, 3 GΩ ≧ Radjust is obtained.

From the above results, the results are summarized for the case where the length of the cable is the same and the distance between the discharge electrode and the counter electrode is changed to 2 mm to 10 mm. The gap between the discharge electrode and the counter electrode is 2 mm and the discharge voltage is 2 kV. For ion generator,
2GΩ ≦ Radjust ≦ 9.6GΩ is obtained.
Similarly, for an ion generator with a 10 mm gap between the discharge electrode and the counter electrode and a discharge voltage of 10 kV,
3GΩ ≦ Radjust ≦ 10GΩ is obtained.
For the ion generator with a discharge voltage of 3 kV examined above,
3 GΩ ≦ Radjust ≦ 6.1 GΩ is obtained, and it can be seen that it is included in the above range.

Next, the case where the electrode structure is the same and the cable length is changed will be considered. The maximum allowable discharge time t is 0.5 seconds, the discharge electrode voltage V0 at the start of discharge is 3 kV, the discharge electrode voltage V at the time of discharge is 2 kV, the electric parasitic capacitance Ccable of the cable is 30 pF, and the cable length is corrected. 14 cm, the resistance value Radjust of the ground resistance 5 is Radjust ≦ −0.5 / (30 pF × ln (1-2 / 3)) = 15 GΩ from the relational expression (6).
Get.

Further, when the electrode structure is the same and the cable has an electric parasitic capacitance Ccable of 150 pF and the length of the cable is set to 70 cm, the resistance value Radjust of the ground resistance 5 is Radjust ≦ −0.5 / (150 pF × ln (1-2 / 3)) = 3 GΩ
Get.

Further, consider the case where the maximum allowable discharge time t is 0.3 seconds. When the discharge electrode voltage V0 at the start of discharge is 3 kV, the discharge electrode voltage V at the time of discharge is 2 kV, the electric parasitic capacitance Ccable of the cable is 30 pF, and the cable length is 14 cm, the resistance value Radjust of the ground resistor 5 is related From equation (6)
Radjust ≦ −0.3 / (30 pF × ln (1-2 / 3)) = 11 GΩ
Get.

In addition, when the electric parasitic capacitance Ccable of the cable is 150 pF and the cable length is 70 cm, the resistance value Radjust of the ground resistance 5 is obtained from the relational expression (6)
Radjust ≦ −0.3 / (150 pF × ln (1-2 / 3)) = 2.2 GΩ is obtained.

Summarizing the above results, a range of 3 GΩ ≦ Radjust ≦ 9.6 GΩ can be obtained as a range that can be used in common for the ion generator for device incorporation. Moreover, as a range which can be applied mutatis mutandis, 2.2 GΩ ≦ Radjust ≦ 3 GΩ can be added.
The final Radjust value is determined by adding other constraint conditions such as cost and operation margin to this relational expression.

  Relational expression (3) is a relational expression between the discharge voltage and the ground resistance Radjust, which indicates that the discharge electrode voltage during steady operation is affected by the value of Radjust, and the output power of the high voltage generation circuit 2 is a constraint condition. It becomes. If the atmospheric conditions are the same, the interelectrode distance between the discharge electrode and the counter electrode is the largest factor that determines the discharge start voltage. The discharge electrode voltage and discharge current after the start of discharge are automatically determined mainly due to the structure of the electrode assembly 4.

  The relational expression (6) is a relational expression between the electric parasitic capacitance Ccable of the cable and the resistance value Radjust of the earth resistance. If the cross-sectional shape of the cable 3 does not change when the same electrode assembly is used, Determines the resistance value Radjust of the earth resistance. The discharge start voltage and the discharge voltage determined by the structure of the electrode assembly at this time are constraints.

  FIG. 7 is a graph comparing the electrode voltage during steady operation when the earth resistance 5 is 3 GΩ and 6 GΩ when the discharge electrode 4 a in the ion generator 1 is set to a negative potential. As shown from the equation (8), an electrode voltage lower than the discharge voltage threshold is secured when Radjust = 3 GΩ. It can be seen that when Radjust = 6 GΩ, a lower electrode voltage is generated than when Radjust = 3 GΩ.

  In general, when the ion generator is continuously used, the discharge electrode 4a is covered with impurities as the cumulative operation time becomes longer, so that the voltage required for discharge gradually increases. For this reason, in the ion generator 1 of this embodiment, the maximum output voltage of the high voltage generation circuit 2 is set to a voltage that is higher in absolute value than the discharge start voltage during cleaning. By adjusting the resistance value Radjust of the ground resistance, the maximum output voltage corresponding to the required service life can be obtained in advance without changing the output characteristics of the high voltage generation circuit 2.

  FIG. 8 is a graph showing an output waveform of the step-up transformer of the high voltage generation circuit 2 when there is a ground resistance between the discharge electrode and the shield, and FIG. 9 when there is no ground resistance. Although the peak portion of the negative voltage waveform in FIG. 8 and the broken-line circle portion in FIG. 8 are missing the peak portion, the broken-line circle portion in FIG. Maximum.

  This is because the charge accumulated in the cable 3 is recharged to the discharge electrode 4a via the ground resistor 5, and the curvature of the graph changes and the peak portion is missing. That is, since recharging is not performed when the resistance value is infinite, the graph becomes a charging curve of the CR circuit, and the peak portion is eliminated. As the resistance value of the ground resistor 5 increases, the absolute value of the negative peak voltage increases.

  FIG. 10 shows a mounting example of the ground resistor 5 according to the present embodiment. A substrate mounting example in which three resistors 51, 51, 51 are mounted in series on the earth resistance substrate 13 is shown. The earth resistance board 13 is a double-sided board, and FIG. 10 is a view of the earth resistance board 13 as seen from the board pattern surface. The land to which the high voltage potential line 3a of the cable 3 is connected for relay is connected to the pattern surface. 13 a, a land 13 c to which the shield 3 c is connected, and lands 13 b and 13 b that serve as relay connection portions of the three resistors 51 are formed. In the drawing, HV is displayed on the land 13a to which the high voltage potential line 3a is connected, and GND is displayed on the land 13c to which the shield 3c is connected.

  After the high voltage potential line 3a of the cable 3 is once connected to the land 13a, the high voltage potential line 3a on the output side is connected and output again. The ground resistor 5 is electrically connected in parallel with the high voltage potential line 3a at the land 13a, and finally connected to the land 13c while being relayed by the lands 13b and 13b. The resistors 51, 51, 51 are mounted on a mounting surface that is the back surface of the pattern surface. The ground resistor 5 is formed by connecting one or a plurality of resistors 51 in series. The voltage of each land 13b, 13b connecting the resistors is divided by the resistors 51, 51, 51 between the HV-GND voltages. Voltage.

  When the output voltage of the high voltage generation circuit 2 of the ion generator 1 is 10 kV, a potential difference of several kV is generated at both ends of each resistor 51. Since each resistor 51 has a very large resistance value as shown in the above-described calculation formula, electric leakage easily occurs. Therefore, the distance between each resistor and other conductors is more than an insulation distance that can prevent electric leakage. There is a need. In consideration of the influence on the circuit operation, the resistivity of the insulating material needs to be about 100 times the combined resistance value of the ground resistor 5.

  Therefore, the insulating material is a resin having a dielectric strength greater than that of air, such as urethane resin, applied to the lead portion of the resistor 51 and the soldered portion of the land so as not to be exposed, or such a portion is not exposed. It is preferable to fill them as described above. General urethane resin characteristics include a volume resistivity of 1000 GΩ · m and a withstand voltage of about 20 kV / mm. The insulating material to be applied and filled is not particularly limited to the urethane resin, and may be any material that satisfies the insulating characteristics.

  The ground resistor 5 of the present embodiment is used by being inserted in the middle of the cable 3 as shown in FIG. 11, and can be inserted in any place of the cable 3 according to restrictions. When the cable 3 is long and the electric parasitic capacitance becomes large, a plurality of grounding resistors 5 may be used by dividing the cable 3 at an appropriate length.

(Embodiment 2)
FIG. 12 is a schematic diagram showing a configuration of an ion generator 200 according to Embodiment 2 of the present invention. In the present embodiment, the earth resistor 5 is integrated with the electrode assembly 4 to form an electrode assembly 41. The counter electrode 4b is disposed around the discharge electrode 4a, and resistors 51, 51, This is an example when 51 is arranged and connected. As in the first embodiment, the high voltage generation circuit 2 and the electrode assembly 41 are connected by a cable 3 having a length of about 35 cm.

  13 is a plan view showing a mounting state of the electrode assembly 41, and FIG. 14 is a bottom view of the electrode assembly 41 in FIG. FIG. 13 shows the shape viewed from the pattern surface of the substrate. The pattern surface has a land 14a which is a connection portion of the high voltage potential line 3a of the cable 3 and is a mounting portion of the discharge electrode 4a, and a counter electrode 4b. Lands 14c to which the shield 3c is connected as attachment portions and lands 14b, 14b, 14b, and 14b serving as relay connection portions of the three resistors 51 are provided.

  In the ion generator 200 of the present embodiment, the circuit board 14 is a double-sided board, and the discharge electrode 4a is a needle-like metal rod, and stands on the mounting surface of the circuit board 14 that is the back surface of the board pattern surface of FIG. Installed and fixed. The counter electrode 4b is a metal plate provided with a circular hole, which is formed by bending in an L shape, and the substrate of FIG. 13 is arranged so that the tip of the discharge electrode 4a is the center of the circular hole of the counter electrode 4b. The counter electrode 4b is installed on the mounting surface of the circuit board 14 which is the back surface of the pattern surface. The leg portion of the counter electrode 4b is soldered to a land 14c which is a connection portion of the shield 3c.

  In a state where the discharge electrode 4a and the counter electrode 4b are erected, the electrode assembly 4 is surrounded by a case 12 formed of an insulating material so as not to directly touch the peripheral member. The earth resistor 5 is formed by connecting resistors 51, 51, 51 in series, and is arranged on the mounting surface of the circuit board 14 so as to surround the discharge electrode 4 a and the counter electrode 4 b from the outside of the case 12. 14 lands 14 b, 14 b, 14 b, 14 b are relayed and fixed by soldering, and one end of the connected resistors 51, 51, 51 is connected to the high voltage potential line 3 a and the other end is connected to the shield 14 c. Are connected as shown by thick solid lines in the figure.

  In order to insulate a voltage of about 10 kV, which is a discharge voltage of the ion generator, the entire pattern surface of the circuit board 14 between the portion other than the electrode assembly 4, that is, outside the case 12 and the case 11, and It is sufficient if an insulating material is applied or filled so as to cover the lead portions of the resistors 51, 51, 51 on the mounting surface of the circuit board 14. As in the first embodiment, the insulating material is a urethane resin or other resin material having insulating performance. Further, the peripheral space of the electrode assembly 4 is not only necessary as a structure for attachment, but also acts as an insulating space, so that the excess space can be used effectively.

(Embodiment 3)
FIG. 15 shows a schematic configuration of an ion generator 300 according to Embodiment 3 of the present invention. In this embodiment, in place of the electrode assembly 41 used in the second embodiment, an electrode assembly 42 in which two sets of electrode assemblies 41 are mounted on one substrate is used. Correspondingly, a high voltage generation circuit 21 is used instead of the high voltage generation circuit 2 used in the first and second embodiments. Further, the cable 31 is used instead of the cable 3.

  The cable 31 has a structure in which two cables 3 are bundled, and includes a high-voltage potential line 31a that is a core wire, an insulating coating 31b that covers the high-voltage potential line, and a shield made of a conductor that covers the outside of the insulating coating. And 31c each including two sets. In the present embodiment, as in the first and second embodiments, the distance from the high voltage generation circuit 21 to the electrode assembly 42 is 35 cm.

  The high voltage generation circuit 21 connects a rectifier that outputs positive electricity and a rectifier that outputs negative electricity in parallel to the output terminal of the high voltage generation circuit 2, and discharges each output voltage via the cable 31. This is output to the electrodes 4a and 4a. The electrode assembly 42 is obtained by integrating the two electrode assemblies 41 used in the second embodiment. In this embodiment, one electrode assembly 41 has positive high voltage electricity and the other has negative high voltage. Supply electricity.

When the electrode assembly 42 is used in the atmosphere, positive ions are generated from the discharge electrode to which positive high voltage electricity is applied, and negative ions are generated from the discharge electrode to which negative high voltage electricity is applied. ^{When +} (H ₂ O) m (m is an arbitrary natural number) and negative ions are generated as O ₂ ⁻ (H ₂ O) n (n is an arbitrary natural number), positive and negative ions released into the air are floating bacteria. It attaches to viruses and reacts on its surface to generate hydroxyl radicals, OH and other active species which are active species. These active species can kill or inactivate planktonic bacteria and viruses.

  In the present embodiment, positive electricity is supplied to one of the two electrode assemblies 41 and negative electricity is supplied to the other, but high voltage electricity having the same polarity may be supplied to both. In this case, the effect of releasing the positive and negative ions cannot be exhibited, but the shortage of positive ions or negative ions in the environment can be compensated for and the ion balance can be adjusted.

  In FIG. 16, the structure which looked at the circuit board 15 of the electrode assembly 42 which concerns on Embodiment 3 of this invention from the pattern surface is shown. In the present embodiment, two electrode assemblies 41 described in the second embodiment are configured on a single substrate so as to face each other. The output terminal of the high voltage generation circuit 21 is provided with a rectifier that outputs positive electricity and two rectifiers that output negative electricity, and is connected to the positive electrode through the high voltage potential lines 31 a and 31 a housed in the cable 31. And negative high-voltage electricity can be separately supplied to the corresponding electrode assemblies 41, 41.

  In the present embodiment as well as in the second embodiment, the counter electrode 4b made of a metal plate is disposed so that the circular hole is located around the tip of the needle-like discharge electrode 4a, and the periphery is surrounded by the case 12. Further, resistors 51, 51, 51 are arranged in series around them. In this example, two sets of electrode assemblies 41 configured as described above are provided on a common substrate. As in the first embodiment, the high voltage generation circuit 21 and the electrode assembly 42 are connected by a cable 31 having a length of about 35 cm.

  On the pattern surface of the circuit board 15, the connection lands 15a and 15a of the two high voltage potential lines 31a and 31a of the cable 31, the land 15c connected to the shields 31c and 31c, and the six resistors 51 and 51, ... 8 relay lands 15b are provided at 8 locations. The two discharge electrodes 4a and 4a are fixed to the connection lands 15a and 15a so as to stand on the mounting surface, which is the back surface of the circuit board 15 in FIG. The counter electrodes 4b and 4b are installed. The leg portions of the two counter electrodes 4b and 4b are soldered to the land 15c. In a state where the discharge electrodes 4a and 4a and the counter electrodes 4b and 4b are erected, the electrode assemblies 4 and 4 are surrounded by a case 12 formed of an insulating material so as not to directly touch the peripheral members.

  The earth resistors 5 and 5 are resistors 51, 51 and 51 connected in series, and two sets are prepared for a positive electrode and a negative electrode, respectively, and on the mounting surface of the circuit board 15, the discharge electrodes 4a and It arrange | positions so that the circumference | surroundings with the counter electrode 4b may be enclosed, it relays by each land 15b, 15b, ... 15b on the circuit board 15, and is fixed by soldering, One end of the connected earth resistance 5,5 is connected. The high voltage potential lines 31a and 31a and the other end are connected to the land 15c as shown by the thick solid line in the figure. Two sets configured as described above are formed on a single substrate. The land 15c shares the ground potential with the high voltage generation circuit 21 through the shield 31c.

  Resistors 51 on the entire pattern surface of the circuit board 15 and the mounting surface of the circuit board 15 between portions other than the two electrode assemblies 4 of the ion generator 300, that is, between the cases 12 and 12 and the case 11. , 51,... 51 are covered with an insulating material such as urethane so as to cover the lead portions, or are filled and protected.

(Embodiment 4)
FIG. 17 shows another example of the third embodiment. The difference from the third embodiment is that the two electrode assemblies 41 are not configured as a single unit on the same substrate, but are configured separately and installed in the outer case. Other configurations are the same as those of the third embodiment.

  Since the two electrode assemblies 41 and 41 are independent from each other, each electrode assembly 41 can be installed in a different place. Therefore, when the space for installing the electrode assembly 42 used in the third embodiment cannot be formed as a whole, by securing two or more spaces in which only one electrode assembly 41 can be accommodated and taking a distance, An ion generator that emits positive ions and negative ions can be used without difficulty according to the product shape. By doing so, it is expected that the degree of freedom in design will be improved and the number of devices that can be equipped with an ion generator will increase.

  Also in the fourth embodiment, high voltage electricity having the same polarity can be applied to the two electrode assemblies 41 and 41. Since the effect in this case was described in the third embodiment, it will not be described again.

(Embodiment 5)
FIG. 18 is a schematic diagram showing the configuration of an ion generator 400 according to Embodiment 5 of the present invention. In the present embodiment, the ground resistor 5 and the high voltage generation circuit 2 described in the first embodiment are integrated to form a high voltage generation circuit 22, which is used in combination with the cable 3 and the electrode assembly 4. This is an example. As in the first embodiment, the high voltage generation circuit 22 and the electrode assembly 4 are connected by a cable 3 having a length of about 35 cm.

  FIG. 19 is a plan view showing a mounting state of the high voltage generation circuit 22. FIG. 19 shows the shape of the substrate as viewed from the pattern surface. The high voltage generating circuit 2 and the ground resistor 5 are arranged as separate substrates, and both are electrically connected by a jumper indicated by a thick solid line in the drawing. Similarly to the first embodiment, on the pattern surface of the ground resistance substrate 13 constituting the ground resistance 5, a land 13a serving as an attachment portion of the high voltage potential line 3a of the cable 3, and a land 13c to which the shield 3c is connected, Lands 13b and 13b serving as relay connection portions of the three resistors 51 are provided. The land 13a is connected to the high voltage potential line 3a and one end of the earth resistor 5 is connected. The land 13c is connected to the shield 3c and the other end of the earth resistor 5.

  Also in the ion generator 400 of this embodiment, a rectifier is provided at the output end of the high voltage generation circuit 2 to output positive or negative high-voltage electricity. A jumper is connected between the output terminal of the high voltage generation circuit 2 and the land 13a of the earth resistance substrate 13 to output high voltage electricity. In addition, the land 13c of the earth resistor substrate 13 is connected to the ground line of the high voltage generation circuit 2 by a jumper so that the ground is shared. The land 13c becomes the ground potential together with the shield 3c.

  The earth resistance substrate 13 is a double-sided substrate, and the three resistors 51, 51, 51 are erected on the mounting surface, which is the back surface of the substrate pattern surface of FIG. The ground resistor 5 is formed by connecting resistors 51, 51, 51 in series, starting from the land 13 a of the ground resistor substrate 13, connected via the relay lands 13 b, 13 b, and connected to the land 13 c having the last end at the ground potential. And fixed by soldering.

In order to insulate the discharge voltage in the high voltage generation circuit 22 of the ion generator 400, it is preferable to provide a partition wall or a gap between the high voltage generation circuit 2 and the ground resistor 5. When both substrates are shared, it is preferable to provide a sufficient gap or slit between the patterns. After having been configured in this way, an insulating material is provided so as to cover the entire pattern surface of each substrate of the high voltage generating circuit 2 and the ground resistor 5 and the lead portion of the resistors 51, 51, 51 on the mounting surface of the ground resistor substrate 13. Apply or fill. As in the first embodiment, the insulating material is a urethane resin or other resin material having insulating performance.
(Summary of invention)

  ADVANTAGE OF THE INVENTION According to this invention, in the ion generator which connected between the high voltage generation circuit and the discharge electrode with the long cable, the electric capacitance parasitic on a cable can be controlled appropriately. It is possible to obtain an ion generator that ensures an appropriate ion concentration during the operation of the ion generator and quickly reduces the charge remaining on the electrode after the ion generation operation is stopped to prevent unintended discharge. . In addition, it is possible to predict the improvement of the discharge voltage due to the secular change of the ion generator, and to set and change the cable length and the resistance value of the ground resistance as a pair, the convenience in production is improved.

1,100,200,300,400 Ion generator 2,21,22 High voltage generation circuit 3,31 Cable 4,41,42 Electrode assembly 5 Earth resistance 11 Case (outer)
12 Case (inside)
13 Ground resistance board 14, 15 Circuit board

Claims (5)

A discharge electrode for discharging in air;
A high voltage generating circuit for generating high voltage electricity;
An ion generator comprising: a cable for connecting the discharge electrode and the high voltage generation circuit to supply high-voltage electricity to the discharge electrode;
The cable is an electric wire that conducts high-voltage electricity,
An insulator covering it, and a shield covering the outside of the insulator;
The electric wire and the shield are connected by an electric resistor,
The ion generator is further characterized in that the shield is grounded. Providing a counter electrode connected to the shield at a position corresponding to the discharge electrode;
The electrical resistor connects the discharge electrode and the counter electrode,
It is installed in the vicinity of the discharge electrode,
The ion generator according to claim 1. The ion generator according to claim 1, wherein the electrical resistor is provided at an output end of the high voltage generation circuit to connect the electric wire and the shield. The ion generator according to claim 1, wherein the electric resistor is provided by being inserted in the middle of the cable to connect the electric wire and the shield. 5. The ion generator according to claim 1, wherein the electrical resistor has a resistance of 3 GΩ to 9.6 GΩ.