JP4367580B2 - Static eliminator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a static eliminator for bringing the charge amount of a target object charged to a positive or negative charge close to zero.
[0002]
[Prior art]
If the target object is charged in a liquid crystal production line, etc., dust may adhere to the product and the product may become defective.If the object is transported by a conveyor, etc., the small target object will be charged. As a result, the products are attracted and contacted, and the production line may stop. For this reason, there are cases where a large number of static eliminators are placed in a limited space where it is necessary to suppress the generation of static electricity.
[0003]
Static electricity is caused by positive or negative charges accumulated in the target object, and the charged potential of the target object due to static electricity is determined by measuring the surface potential of the target object with the ground as the reference potential. Yes. The principle of static elimination is that the charge accumulated in the target object is poured into the ground, or ions with the opposite polarity to the accumulated charge are blown to neutralize the charged potential, thereby neutralizing the target object. The accumulated charge is close to zero.
[0004]
Applying the principle of static elimination described above, as a conventional static eliminator, DC high voltage or AC high voltage is applied to the electrode needle to generate positive and negative ions from the electrode needle, and this ion is sprayed on the target object. What is made is known. FIG. 8 is a circuit diagram illustrating an example of a static eliminator using alternating current. In the figure, 20 is a power supply unit, 21 is a step-up transformer, 22 is an electrode needle, and f is a fan. The primary winding of the step-up transformer 21 is connected to a low-voltage power supply unit 20 such as a commercial frequency power supply, and an AC high voltage of, for example, about 3000 to 10000 volts is output from the secondary winding and applied to the electrode needle 22. From the electrode needle 22, positive and negative ions are generated alternately.
[0005]
The electrode needle 22 is arranged at a certain distance from the target object, but the ions are blown by the repulsive force of plus and minus ions and adhere to the target object. When the repulsive force is weak and the ions generated from the electrode needles are difficult to adhere to the target object as they are, a fan f is provided to spray the ions generated from the electrode needles onto the target object as shown in the figure. Sometimes. Positive and negative ions generated from the electrode needle 22 are sprayed onto the target object by the fan f described above to neutralize the charging potential.
[0006]
FIG. 9 is a circuit diagram illustrating an example of a DC type static eliminator. In the figure, 1 is a DC or AC low voltage power supply unit, 2 is a connection line, 3 is a power supply control circuit, 4 is a positive high voltage generation circuit, 5 is a negative high voltage generation circuit, 6 is a positive electrode needle, 7 is a negative electrode needle, 8 is a fan, and 9 is a ground wire. For the positive high voltage generation circuit 4 and the negative high voltage generation circuit 5, for example, a voltage doubler rectification circuit composed of a capacitor and a diode is used. Also in this case, the fan is used only when the repulsive force of positive and negative ions is weak, and the fan may not be provided.
[0007]
FIG. 10 is a circuit diagram showing an example of a voltage doubler rectifier circuit. FIG. 10A shows a positive high voltage generation circuit, and FIG. 10B shows a negative high voltage generation circuit. . When such a voltage doubler circuit is used, from the secondary side of the transformer, if the number of units consisting of a diode and a capacitor is n with respect to the voltage input to the primary side winding, a direct current of n times the input voltage High voltage is output.
[0008]
The power supply control circuit 3 performs voltage control of the positive and negative high voltage generation circuits 4 and 5 and operation control such as starting and stopping of the fan 8. A DC high voltage is applied to the positive and negative electrode needles 6 and 7 from the positive and negative high voltage generation circuits 4 and 5, respectively, and positive and negative ions are generated from the tip of the electrode needle. The fan 8 blows positive and negative ions generated from the electrode needles onto the target object.
[0009]
[Problems to be solved by the invention]
In the static eliminator using alternating current or direct current, when the target object is charged, ions having the opposite polarity to the charged charge are sprayed to neutralize the charged potential of the target object. In this case, the static eliminator is required to generate the same amount of positive and negative ions so that the target object can be neutralized regardless of whether it is charged with positive or negative polarity. For example, if the target object is charged positively, negative ions may be sprayed mainly. However, if excessive ions are sprayed excessively, the negatively charged ions will be charged. It doesn't mean that
[0010]
In order to prevent such a phenomenon from occurring, the static eliminator is required to always generate positive and negative ions in the same amount to balance the ions so that the charged potential of the target object is not biased to one polarity. ing. In addition, once the target object has been neutralized, the target object must always generate the same amount of positive and negative ions so that the target object is not charged with either positive or negative polarity. There is.
[0011]
However, in the conventional static eliminator, the applied voltage and the like are controlled on the input side of the electrode needle so that positive and negative ions are generated in the same amount. However, the amount of positive and negative ions cannot always be generated in the same amount from the static eliminator.
[0013]
Furthermore, since it is impossible to detect how much potential the target object is charged with positive or negative polarity, there is a problem that the amount of ions generated by the static eliminator cannot be accurately controlled.
[0014]
Furthermore, since no means for determining whether the target object has been neutralized is provided, it is possible that the product has failed due to a mistake that the neutralization process has ended even though the target object has not been neutralized. There was a problem of causing the occurrence.
[0015]
Furthermore, there is a problem that proper maintenance for generating predetermined ions from the static eliminator cannot be performed because there is no means for judging deterioration or damage of the ion generating part such as the electrode needle.
[0016]
The present invention has been made in view of such a problem, and an object of the present invention is to provide a static eliminator configured to always generate the same amount of positive and negative ions from the tip of the electrode means so as to maintain the ion balance. .
[0018]
It is another object of the present invention to provide a static eliminator configured to accurately detect how much potential the target object is charged with positive or negative polarity.
[0019]
It is another object of the present invention to provide a static eliminator configured to display the status of static elimination of the target object so that the operator can determine whether the static elimination has been performed normally.
[0020]
Furthermore, it aims at providing the static elimination apparatus comprised so that the deterioration and damage of an ion generation part could be alert | reported and a static elimination apparatus could be maintained appropriately.
[0021]
[Means for Solving the Problems]
In order to achieve such an object, according to the present invention, there is provided a step-up transformer for stepping up the power supply voltage to a voltage having a predetermined amplitude, high voltage generating means for outputting the voltage as a pulse voltage, and the pulse voltage supplied In the static eliminator provided with electrode means for generating positive and negative ions from the tip according to the pulse width of the pulse voltage, a ground line provided in the secondary winding of the step-up transformer, Provided in the ground wire;A detection resistor for detecting a current having a magnitude proportional to the difference between the positive and negative ion amounts generated from the electrode means, which is zero in an ion balance state where the positive and negative ion amounts generated from the electrode means are equivalent. When,By feeding back the current value detected by the detection resistor to the high voltage generating means, the current detected by the detection resistor is brought close to zero.Control means for controlling the pulse width of the pulse voltage of the high voltage generating means;Monitoring means for monitoring the voltage-to-current characteristics of the high voltage generating means, and alarm means for generating an alarm signal when the comparison result is outside a certain range by comparing the monitoring result by the monitoring means with a reference value It is characterized by providing.
[0023]
Furthermore,It has a display means for displaying the state of charge of the target object by a signal from the detection resistor, and controls the output voltage of the high voltage generating means.
[0024]
Furthermore,By providing display means for displaying the state of charge of the target object by a signal from the detection resistor, the operator can determine the state of charge removal of the target object.
[0025]
Furthermore,An alarm means for generating an alarm when a value of a signal from the detection resistor is less than a predetermined range is provided.
[0026]
The present invention is also directed to a static eliminator configured to provide a fan that blows ions generated from electrode means onto a target object, and the static eliminator configured to provide such a fan also includes the above features of the present invention. Is provided.
[0027]
Due to this feature of the present invention, the output voltage of the boosting means is controlled by detecting the difference between the positive and negative ion amounts generated from the electrode means, so that the same number of positive and negative ions are always output from the electrode means. The charge potential of the target object can be brought close to zero while maintaining the ion balance.
[0029]
In addition, a sensor that detects the polarity and magnitude of the charged potential is placed in the vicinity of the target object, and the state of charge of the target object is displayed based on the detection signal, so the operator confirms the charge state of the target object. it can. Further, since the high voltage generating means is controlled in accordance with the charging state of the target object detected by the sensor, the target object can be discharged quickly.
[0030]
Further, since the state of charge removal of the target object can be displayed, it is possible to avoid the occurrence of a product failure due to misidentification that the charge removal process is completed while the target object is not discharged.
[0031]
Furthermore, since the alarm means is provided so that the deterioration or damage of the ion generation unit can be notified, the static eliminator can be properly maintained.
[0032]
Each of these actions can also be obtained in a static eliminator configured to provide a fan that blows ions generated from electrode means onto a target object.
[0033]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below. FIG. 11 is a circuit diagram illustrating the principle of the present invention. In the figure, positive and negative ions generated from the electrode needles Y1 and Y2 provided on the output side of the high voltage generator X of the static eliminator are blown toward the target object by the fan Z. The positive and negative ion flows flowing in the air at this time can be considered as a current between the high voltage generating portion X and the ground. That is, the current i flowing from the high voltage generator X toward the ground₁Represents a negative ion flow, and the current i flowing from the ground toward the high voltage generator X₂Represents a positive ion flow.
[0034]
The present invention is made by paying attention to the fact that from such a correlation between the ion flow and the current, the amount of plus and minus ions generated from the static eliminator is neutralized and the current becomes zero if the number is the same. It is a thing. In the present invention, the direction and magnitude of the current flowing between the power supply unit of the static eliminator and the ground is detected, and the power supply unit is controlled so as to make this current zero. By such control of the power supply unit, a predetermined number of positive and negative ions are always generated from the static eliminator.
[0035]
FIG. 1 is a circuit diagram showing an example of a static eliminator using direct current according to the present invention. In the figure, 1 is a DC or AC power supply unit, 2 is a connection line, 3 is a power supply control device, 4 is a positive high voltage generation circuit, 5 is a negative high voltage generation circuit, 6 is a positive electrode needle, and 7 is a positive electrode needle. The negative electrode needle 8 is a fan provided when necessary to spray ions on the target object, and is installed at a position close to the electrode needle, but the ions adhere to the target object only by the repulsive force of the positive and negative ions. In some cases, the fan can be omitted. 9 is a ground wire. Such a configuration is the same as that of the conventional static eliminator described with reference to FIG. 8, but the present invention is characterized in that a detection resistor 10 for detecting positive and negative ions is connected to the ground wire 9. The power supply control device 3 is provided with a display device O and an alarm device P whose operation will be described later.
[0036]
As described above, static elimination on the target object is performed by blowing ions having a polarity opposite to the charged polarity, but the ion flow at this time is formed with the ground as a reference potential, When the amount of positive or negative ions generated by the static eliminator is larger than the amount of ions of the other polarity, the difference value is the magnitude of the current in the ground line 9. Proportional. For this reason, by measuring the magnitude and direction of the current of the grounding wire 9, it can be determined how much positive or negative ions are generated from the static eliminator.
[0037]
In the present invention, by using a detection resistor connected to the grounding wire, it is determined which of the polar ions generated from the static eliminator is large, so that the amount of positive and negative ions generated is always equal. I have control. In other words, in an ion balance state in which the amount of positive and negative ions generated is equal, the potential between the ground and the static eliminator becomes zero due to neutralization, and the current flowing through the detection resistor 10 is not detected. Therefore, the value of the current flowing through the ground line is fed back to the power supply control circuit 3 to control the voltage of the positive and negative high voltage generating circuits so as to balance the ionization of the static eliminator.
[0038]
FIG. 2 is a partial circuit diagram of the power supply control circuit 3 showing a specific example for performing such ion balance control of the present invention. In the figure, reference numeral 1 'denotes a high voltage generator for boosting the voltage of the power supply unit to a predetermined high voltage. As shown in the figure, a current-voltage conversion circuit 11 that converts a current value detected by a detection resistor 10 connected to a ground line into a voltage signal, an amplifier 12 that amplifies the signal of the current-voltage conversion circuit 11, and an analog of the amplifier 12 A control circuit 14 for supplying signals for controlling the output voltages of the positive and negative high voltage generation circuits 4 and 5 based on the signals of the A / D conversion circuit 13 and the A / D conversion circuit 13 for converting the signals into digital signals. Is provided.
[0039]
FIG. 3 is a timing chart showing an example of a pulsed voltage waveform output from the positive and negative high voltage generation circuits 4 and 5 according to a control signal formed by the control circuit 14. 3A is a voltage waveform for generating positive ions at time ta in period T, and FIG. 3B is a voltage waveform for generating negative ions at time tb in period T. . The amplitude value of the voltage waveform is selected, for example, 6000V. In this embodiment, the ion balance is maintained by controlling the pulse widths ta and tb in accordance with the positive and negative polarities of the signal detected by the current-voltage conversion circuit 11 and the magnitude thereof.
[0040]
In the above example, the configuration in which the positive and negative electrode needles 6 and 7 are attached to the positive high voltage generation circuit 4 and the negative high voltage generation circuit 5 has been described. In the static eliminator of the present invention, the configuration of the ion generation unit is described. However, the present invention is not limited to this, and the positive and negative high voltage generation circuit may be provided with an electrode means such as a long line such as a thin wire or a member having a protrusion, thereby forming an ion generation unit.
[0041]
In FIG. 1, the power supply control device 3 is provided with a display device O. As shown in FIG. 2, this display device O detects the state of how many ions of which polarity are generated with respect to positive and negative ions generated from the electrode needles 6 and 7. detectionResistance detectsThis is a signal display, but this detectionResistance detectsThe signal can be considered to be a signal of the above characteristics of the ion generation unit and a signal of the ion adhesion state of the target object.
[0042]
In other words, if the ions attached to the target object are balanced with positive and negative polaritiesResistance detectsThe signal is zero, but it is detected when there is a large amount of ions of any polarityResistance detectsThe signal will not be zero. Detection is possible because the operator can determine the state of charge removal of the target object by monitoring the data displayed on the display device O.Resistance detectsBy controlling the power supply control device 3 so that the signal becomes zero, it is possible to confirm the completion of the charge removal of the target object.
[0043]
The power supply control device 3 is provided with an alarm device P. This alarm device P generates an alarm for positive and negative ions generated from the electrode needles 6 and 7 when the amount of ions generated is less than a predetermined range due to wear of the electrode needles or adhesion of dust. It is. The alarm device is configured to monitor the voltage-to-current characteristics of the positive and negative high voltage generation circuits 4 and 5 and generate an alarm signal if the comparison value is outside a certain range compared to the reference value. Can do. By providing such an alarm device, an operator can properly perform maintenance of the static eliminator.
[0044]
FIG. 4 is an explanatory diagram of an example in which each component of the static eliminator of the present invention is unitized and stored in a case. As shown in the figure, the unit A is provided with a DC or AC power supply unit 1, a connection line 2, a power supply control circuit 3, a ground line 9, and a detection resistor 10 and accommodated in a case. In unit B, a positive high voltage generation circuit 4, a negative high voltage generation circuit 5, a positive electrode needle 6, a negative electrode needle 7, and a fan 8 are arranged and housed in a case. Units A and B are connected by a cable C having connectors at both ends. When a commercial frequency power source is used as the power source unit, the power source unit 1 can be arranged separately from the unit A.
[0045]
The static eliminator is required to be as small as possible depending on the location of the target object depending on the location of the target object, but in order to generate a constant high voltage, the size of the static eliminator is reduced due to the capacity of the step-up transformer. There are limits. When the static eliminator is divided into two units as shown in FIG. 4, only the unit B in which the positive electrode needle 6, the negative electrode needle 7 and the fan 8 necessary for the generation and spraying of ions are separated from the unit A and targeted. Since it can be installed in the vicinity of the object, the space problem can be solved in the same way as the static elimination device is miniaturized. If the static eliminator does not have a fan, only the high voltage generator is stored in the unit B.
[0046]
In addition, since the high voltage generators are arranged together in the unit B, the cable C wired from the unit A on the low voltage side can be used with a thin wire diameter, and a low voltage is applied in the cable. Therefore, even if it is drawn around the floor surface, the operator does not cause an accident such as an electric shock, and the worker can be safe.
[0047]
FIG. 5 is a circuit diagram illustrating another embodiment of the present invention. In this example, the sensor 16 is arranged at a position close to the target object 15 instead of connecting a detection resistor to the ground line. The sensor 16 detects the charging polarity and charging voltage of the target object 15, and supplies the detection signal to the A / D converter 18 via the display device 17. Since the charging state of the target object is displayed on the display device 17 by the detection signal of the sensor 16, the operator can check the charging state of the target object.
[0048]
The detection signal converted into a digital signal by the A / D converter 18 is input to the power supply control device 3 so that a large amount of ions having a polarity opposite to the polarity charged on the target object is sprayed on the target object. Control is performed to temporarily increase the output voltage of one of the high-voltage generation circuits 4 and 5 on the negative side or negative side, and the charge is rapidly discharged from the target object. When the voltage of the high voltage generation circuit decreases and reaches a steady value, the operation mode shifts to the normal sensorless operation mode, and the state of ion balance is maintained and the charging of the target object is brought close to zero.
[0049]
FIG. 6 is a characteristic diagram for explaining static elimination of the target object according to the example of FIG. The solid line in the figure is the output voltage characteristic of the high voltage generation circuit when the sensor is used, and the broken line is the output voltage characteristic of the high voltage generation circuit when the normal sensor is not used. As shown in the figure, when the output voltage of the high voltage generation circuit is controlled as described above using a sensor, the output voltage rapidly decreases from a temporary large value and converges to a steady value.
[0050]
When the voltage doubler generating circuit described with reference to FIG. 10 is used as the DC high voltage generating circuit, for example, when a high voltage of 10000 V is output from the high voltage generating circuit, an output voltage of 5000 V is formed for each positive and negative. A voltage doubler circuit is used. However, when such a high voltage is reached, a unit consisting of a large number of capacitors and diodes is required due to the withstand voltage of the diode that is a component of the voltage doubler circuit, resulting in an increase in cost.
[0051]
For this reason, it is conceivable to apply a high voltage generating circuit for applying positive and negative pulsed high voltages alternately to the electrode means as shown in the circuit diagram of FIG. In the figure, E is a DC power supply, S is a switch, OS is an oscillator, DC / DC is a converter, CO is a capacitor, and N is an electrode needle.
[0052]
FIGS. 13A and 13B are timing charts for explaining the operation of the circuit diagram of FIG. When the oscillator OS opens and closes the switch S with a predetermined period T, the converter DC / DC outputs, for example, a pulsed voltage having an amplitude of 2 V, and the terminal a on the input side of the capacitor CO is shown in FIG. A voltage having a pulse waveform with an amplitude of 2 V as shown is applied. From the output terminal b of the capacitor CO, a positive and negative pulsed output voltage having a maximum amplitude of + V and −V as shown in FIG. 13B is obtained according to the charge / discharge characteristics of the capacitor CO.
[0053]
Therefore, a positive and negative pulse voltage having a waveform as shown in FIG. 13B is applied to the electrode needle N, and positive and negative ions are alternately generated from the electrode needle. Thus, the high voltage generation circuit having the configuration as shown in the circuit diagram of FIG. 13A can also be applied to the static eliminator of the present invention.
[0054]
The above example is an example of a static eliminator using a DC high voltage, but the present invention can also be applied to a static eliminator using an AC high voltage. FIG. 7 is a circuit diagram illustrating an example of a static eliminator using an alternating high voltage. In the figure, 20 is an AC power supply, 21 is a step-up transformer, 22 is an electrode needle, 23 is an A / D converter, 24 is a DC bias power supply device, 25 is a detection resistor, 26 is a detection circuit, 27 is a control circuit, and 28 is This is a voltage control device. From the output side of the step-up transformer 21, a high-voltage alternating current obtained by boosting the power supply voltage to a predetermined voltage is obtained, and the predetermined voltage is applied to the electrode needle via the voltage control device 28. Positive and negative ions are alternately output from the tip of the electrode needle.
[0055]
In this example, since the detection resistor 25 is connected to the ground line of the secondary winding of the step-up transformer via the DC bias power supply device 24, ions generated from the electrode needle 22 are connected to the detection resistor 25. Corresponding positive and negative DC current flows. As in the case of the static eliminator using the DC high voltage in FIG. 1, the detection circuit 26 can determine the difference between the positive and negative ion amounts generated from the electrode needle of the static eliminator, and make this difference zero. The voltage controller 28 is controlled by a signal from the control circuit 27 to maintain the ion balance. The detection circuit 26 can detect the difference between the positive and negative ion amounts by means such as counting the number of positive and negative DC pulses in a certain period.
[0056]
In the AC type static eliminator, since the voltage is supplied from the power source in positive and negative cycles, the electrode needle 22 generates the same amount of positive and negative ions alternately in principle. The positive and negative ions are not always generated from the same amount of electrode needles 22 due to the influence of the above. For this reason, the voltage control device 28 is provided between the step-up transformer 21 and the electrode needle 22 to adjust the voltage level, thereby adjusting the amount of positive and negative ions generated from the electrode needle.
[0057]
Also in the AC type static eliminator, as means for alternately outputting positive and negative ions, a structure having a long object such as a thin wire or a member having a protruding portion may be used instead of the electrode needle. Moreover, it is good also as a structure which provides the fan which blows off ion to a target object.
[0058]
Further, also in the AC type static eliminator, in the same way as the DC type static eliminator as shown in FIG. 1, the output from the electrode needle and the display device O that displays the positive and negative polarities and amounts of ions attached to the object. An alarm device P that generates an alarm when the amount of ions to be output is outside a predetermined range may be provided.
[0059]
【The invention's effect】
As described above, in the present invention,In the static eliminator comprising a high voltage generating means for boosting the power supply voltage to a predetermined voltage, and an electrode means for generating positive and negative ions from the front end by being supplied with the output voltage of the high voltage generating means. A grounding wire provided, a detection resistor provided on the grounding wire for detecting a difference between positive and negative ion amounts formed by the static eliminator, and a positive generated from the electrode means by a signal from the detection resistor Control means for controlling the output voltage of the high voltage generating means is provided so that the number of negative ions is the same.In this way, since the output voltage of the high voltage generating means is controlled by a signal from the detection resistor that detects the difference between the positive and negative ion amounts generated from the electrode means, it is always positive from the tip of the electrode means, The same number of ions can be generated, and the charged potential of the target object can be brought close to zero.
[0061]
Furthermore,By the signal from the detection resistorSince the charging state of the target object is displayed, the operator can check the charging state of the target object. Further, since the output voltage of the high voltage generating means is controlled in accordance with the charging state of the target object detected by the detection resistor, the target object can be quickly discharged.
[0062]
Further, by providing a fan in a position close to the electrode means, ions generated from the electrode means can be sprayed onto the target object to effectively eliminate the charge.
[0063]
Furthermore, since a display means for displaying the state of charge removal of the target object is provided, the operator can confirm whether or not the charge removal of the target object has been completed. It is possible to prevent malfunctions of products due to misidentification.
[0064]
Furthermore, when the ion generating part is deteriorated or damaged, an alarm means for informing the deterioration is provided, so that the static eliminator can be properly maintained.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a configuration in a preferred embodiment of a static eliminator according to the present invention.
FIG. 2 is a circuit diagram showing a configuration of ion balance control of the static eliminator according to the present invention.
FIG. 3 is a timing chart of the static eliminator according to the present invention.
FIG. 4 is an explanatory diagram showing a configuration of another embodiment of the static eliminator according to the present invention.
FIG. 5 is a circuit diagram showing a configuration of another embodiment of the static eliminator according to the present invention.
FIG. 6 is a characteristic diagram in the embodiment of FIG.
FIG. 7 is a circuit diagram showing a configuration of another embodiment of the static eliminator according to the present invention.
FIG. 8 is a circuit diagram of a conventional static eliminator.
FIG. 9 is a circuit diagram of a conventional static eliminator.
10A and 10B are circuit diagrams showing an example of a voltage doubler generation circuit.
FIG. 11 is a circuit diagram illustrating the principle of the present invention.
FIG. 12 is a circuit diagram of a static eliminator using a pulsed high voltage generation circuit.
13A and 13B are timing charts for explaining the operation of an example using the configuration of the circuit diagram of FIG.
[Explanation of symbols]
1 Power supply
2 connecting lines
3 Power supply control device
4 Positive side high voltage generator
5 Negative high voltage generator
6 Positive electrode needle
7 Negative electrode needle
8 fans
9 Grounding wire
10 Sensing resistance

Claims (3)

A high-voltage generating unit that has a step-up transformer that boosts the power supply voltage to a voltage having a predetermined amplitude and outputs the voltage as a pulsed voltage;
In the static eliminator provided with the electrode means for generating positive and negative ions corresponding to the pulse width of the pulse-like voltage from the tip portion when the pulse-like voltage is supplied.
A grounding wire provided on the secondary winding of the step-up transformer;
Provided on the ground wire , zero in an ion balance state in which the positive and negative ion amounts generated from the electrode means are equal, and a size proportional to the difference between the positive and negative ion amounts generated from the electrode means A detection resistor for detecting the current of
Control for controlling the pulse width of the pulse voltage of the high voltage generation means so that the current detected by the detection resistance approaches zero by feeding back the current value detected by the detection resistance to the high voltage generation means. Means,
Monitoring means for monitoring the voltage-current characteristics of the high voltage generating means;
A static eliminator comprising: alarm means for generating an alarm signal when the monitoring result by the monitoring means is compared with a reference value and the comparison value is outside a certain range. The detection resistor is provided between a power supply control device that supplies the power supply voltage and the ground, and detects a direction and a magnitude of a current that flows between the power supply control device and the ground. Static neutralizer.   3. The static eliminator according to claim 1, further comprising a display unit configured to display a charging state of the target object based on a signal from the detection resistor.

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