JP6595796B2 - Charged body static neutralizer - Google Patents

Description

  The present invention relates to a charged body static eliminator, and more particularly to a charged body static eliminator that neutralizes a charged body by consuming energy of the charged body by corona discharge.

  In many cases, a resin molded product molded by a resin molding apparatus is charged by static electricity generated by contact with an article made of another material. When the resin molded product in the charged state is to be transported by a transport robot or the like, the resin molded product adheres to the arm (chuck part) of the transport robot due to the action of static electricity and cannot be separated from the arm. In some cases, there was a problem in handling resin molded products.

  In order to solve such a problem, the applicant has proposed a charged body static eliminator having a configuration as disclosed in Patent Document 1.

Japanese Patent Laying-Open No. 2015-002084

  In the charged body static eliminator as disclosed in Patent Document 1, in order to overcome the characteristic that the negative electrode has a larger scale of corona discharge than the positive electrode, the electrode shape of both electrodes can be changed by making the electrode shape of the positive electrode and the negative electrode different. A configuration is adopted in which the scale of corona discharge is made equal. However, the adoption of such a configuration has revealed the location of the following problems.

That is, there is a problem that the number of parts constituting the product increases, and it takes time to manage inventory and drawings. Here, the labor of inventory specifically includes the types of parts to be arranged, the number of shelves, etc., and the labor of the drawings specifically, the electrode section requires two types of positive and negative drawings. Thus, two types of drawings are required, and even when common parts are changed, the two types of drawings need to be corrected.
Moreover, when assembling two types of electrodes, there is a problem that it is necessary to use different parts separately. This is because there is a risk of producing defective products if the used parts are wrongly selected.For example, if a configuration in which the corona discharge of the negative electrode is excessively mistakenly selected, the generation of ozone will be excessive, which will adversely affect the human body. And the risk of corrosion of surrounding objects. Moreover, when connecting a high voltage cable to an electrode, there exists a subject that the effort which confirms connecting the high voltage cable for positive electrodes to a positive electrode, and connecting the high voltage cable for negative electrodes to a negative electrode arises. In addition, when the connection destination is wrong and a high negative voltage is originally applied to the positive electrode, there is a problem that ozone generation becomes excessive.

  Therefore, the present invention reduces the number of parts as much as possible, and makes it possible to discharge the charged body by appropriate corona discharge without generating excessive ozone at both the positive electrode and the negative electrode. The purpose is to provide a device.

In order to solve the above problems, the present inventor has intensively studied, and as a result, has come up with the following configuration.
That is, a power supply device and a positive electrode and a negative electrode that are electrically connected to the power supply device and arranged in parallel at a necessary interval, the positive electrode and the negative electrode are linear in the same shape The voltage applied to at least the negative electrode of the positive electrode or the negative electrode is a voltage capable of corona discharge and maintained within a predetermined range in which the amount of ozone generated by the corona discharge does not become excessive. A negative-side current limiting resistor for limiting the amount of current supplied to the negative electrode is electrically connected between the negative electrode and the power supply device, and between the positive electrode and the power supply device, the positive current limiting resistor for limiting the amount of current supplied to the positive electrode be electrically connected, the electrical resistance value of the anode-side current limiting resistor, the greater than the electrical resistance of the positive current limiting resistor A charging member discharger characterized and.

According to this configuration, the charged body passes between the positive electrode and the negative electrode when the charged body passes between the positive electrode and the negative electrode within a range that does not cause inconvenience due to ozone generated from the positive electrode or the negative electrode that performs corona discharge. Corona discharge can be generated instantaneously mainly on the surface of the positive or negative electrode. The electrostatic energy of the charged body is consumed by the release of heat and electromagnetic waves (light) due to the corona discharge, and the charged body can be subjected to charge removal in an instant.
In addition, by making the positive and negative electrodes have the same shape, the number of parts of the charged body static eliminator can be reduced compared to the prior art, which can reduce the trouble of managing the charged body static eliminator and the manufacturing cost. become.
Furthermore, the current supplied to the negative electrode can be made smaller than that for the positive electrode with a very simple configuration. As a result, the absolute value of the voltage applied to the positive electrode and the negative electrode can be made equal, so that the amount of ozone generated by corona discharge at the negative electrode is minimized while maintaining the electric field balance between the positive electrode and the negative electrode. Can do. In addition, since the structural difference between the positive electrode and the negative electrode can be completed in the substrate on which the electric circuit is formed, the charged body can be reduced in the number of parts compared to the number of parts of the conventional charged body static eliminator. It is possible to configure a static eliminator.

  The positive electrode and the negative electrode are each electrically connected to the power supply device via a DC voltage amplifier circuit, and the absolute value of the voltage applied to the negative electrode is the absolute value of the voltage applied to the positive electrode. Preferably it is smaller than the value.

  Thereby, even if the positive electrode and the negative electrode are formed of the same electrode, the scale of corona discharge in the negative electrode can be suppressed. Thereby, the amount of ozone generated by corona discharge in the negative electrode can be minimized. In addition, since the structural difference between the positive electrode and the negative electrode can be completed in the substrate on which the electric circuit is formed, the charged body can be reduced in the number of parts compared to the number of parts of the conventional charged body static eliminator. It is possible to configure a static eliminator.

  In the predetermined range, the ozone concentration at a position 30 cm away from the positive electrode and the negative electrode is preferably 0.1 ppm or less.

  Thereby, the presence or absence of generation | occurrence | production of the excessive ozone by corona discharge can be specified objectively.

  According to the configuration of the charged body neutralizing device according to the present invention, it is possible to prevent generation of excessive ozone due to corona discharge in at least the negative electrode of the positive electrode and the negative electrode, and it is possible to reduce the number of parts of the charged body neutralizing device. . Thereby, the procurement cost and management cost of the parts of the charged body neutralizing device are reduced, and a safe charged body neutralizing device can be provided at a lower cost.

It is a schematic block diagram of the charged body static elimination apparatus in 1st Embodiment. It is a schematic block diagram of the charged body static elimination apparatus in 2nd Embodiment.

  Hereinafter, the charged body static elimination apparatus according to the present invention will be described based on the embodiments.

(First embodiment)
FIG. 1 is a schematic configuration diagram of a charged body neutralizing device in the first embodiment.
The charged body neutralizing device 10 according to the present embodiment is provided with a power source device 20 and a positive electrode 30 and a negative electrode 40 that are linear bodies arranged in parallel with a predetermined interval. Each of the positive electrode 30 and the negative electrode 40 is electrically connected to the power supply device 20. Further, the separation distance between the positive electrode 30 and the negative electrode 40 can be appropriately set according to the size of the charging body T to be subjected to the charge removal process or the charging body T and the transport means (not shown) for transporting the charging body T.

As shown in FIG. 1, the power supply device 20 according to the present embodiment includes a power supply unit 22, a control circuit 24, a piezoelectric transformer 26, and a DC voltage amplification circuit 28. The power supply unit 22, the control circuit 24, the piezoelectric transformer 26, and the DC voltage amplifier circuit 28 are electrically connected in the order described.
In addition, the power supply device 20 is not limited to the structure shown in this embodiment, The structure of the power supply device 20 which combined the other well-known structural element suitably can also be employ | adopted.

  In the present embodiment, a commercial power source is used as the power supply unit 22. The AC 100 volt or AC 200 volt supplied from the power supply unit 22 is first converted to 12 VDC by a control circuit 24 equipped with a converter, and then a pulsed voltage signal having an arbitrary peak value by a boost chopper circuit. Is converted to The pulsed voltage signal having an arbitrary peak value generated by the control circuit 24 is then boosted to a maximum of AC 2 kilovolts by the piezoelectric transformer 26. Subsequently, the maximum AC 2 kilovolt voltage is subjected to AC / DC conversion (rectification) and further boosting processing by the Cockcroft-Walton circuit as the DC voltage amplification circuit 28.

  The DC voltage generated in this way is applied (supplied) to the positive electrode 30 and the negative electrode 40. The applied voltage to the positive electrode 30 and the negative electrode 40 of the charged body neutralizing device 10 in this embodiment is maintained so that the absolute value of each applied voltage is equal to or greater than the absolute value of the voltage immediately before the corona discharge start voltage.

  Here, the corona discharge start voltage refers to the voltage applied to the electrode when corona discharge is started. The corona discharge is a phenomenon in which the atmosphere is turned into plasma when the density of electric lines of force generated in the electric field reaches a certain level or more and the electric field becomes stronger. A region where the density of electric lines of force is high is expressed as a strong electric field, and corona discharge occurs in a region where the electric field is strong. The voltage immediately before the corona discharge start voltage refers to a voltage at which corona discharge is immediately started when the density of the lines of electric force increases even slightly due to the approach of the charged body T or the like. If the voltage applied to the positive electrode 30 or the negative electrode 40 becomes equal to or higher than the corona discharge start voltage, corona discharge occurs even if the charged body T does not pass through, and the amount of ozone generated from the positive electrode 30 and the negative electrode 40 increases as the voltage increases. It is dangerous because it increases at an accelerated rate. Therefore, in the present embodiment, the voltages supplied to the positive electrode 30 and the negative electrode 40 are adjusted (the absolute values of the voltages are made different) so that the generation of ozone due to corona discharge does not become excessive. Here, as a predetermined range in which the generation of ozone due to corona discharge does not become excessive, the ozone concentration at a position 30 cm away from the outer surfaces of the positive electrode 30 and the negative electrode 40 is preferably 0.1 ppm or less.

  For the positive electrode 30 and the negative electrode 40 in the present embodiment, electrodes formed in the same material and in the same shape are used. As described above, when the positive electrode 30 and the negative electrode 40 formed on the same electrode are used, the corona discharge start voltage in the negative electrode 40 is significantly lower than the corona discharge start voltage in the positive electrode 30. Therefore, in this embodiment, the voltage applied to the negative electrode 40 is reduced by adopting a circuit configuration for preventing the voltage applied to the negative electrode 40 from becoming extremely higher than the corona discharge start voltage in the negative electrode 40. I am letting.

  As a circuit configuration for reducing the voltage applied to the negative electrode 40, in this embodiment, the Cockcroft-Walton circuit as the DC voltage amplifier circuit 28 is branched into the positive branching portion 28A and the negative branching portion 28B, respectively. The number of booster circuit stages in the positive branching portion 28A and the negative branching portion 28B is different. Specifically, the number of booster circuit stages in the positive branching portion 28A is set to be higher than the number of booster circuit stages in the negative branching portion 28B. Thereby, the absolute value of the final boosted voltage supplied to the negative electrode 40 can be made smaller than the absolute value of the final boosted voltage supplied to the positive electrode 30.

  Note that the Cockcroft-Walton circuit boosts the input voltage to a multiple obtained by multiplying the booster circuit stage number by 2 (when the booster circuit stage number is n, the input voltage is boosted by 2n times. For example, boosting is performed. When the number of circuit stages is one, the voltage is boosted twice, when the number of booster circuit stages is two, the voltage is boosted four times, and when the number of booster circuit stages is three, the voltage is boosted six times. The difference between the number of boosting circuit stages of 28A and the number of boosting circuit stages of the negative branching section 28B is set appropriately so that the voltage immediately before the corona discharge start voltage is applied to both according to the electrode shape of the positive electrode 30 and the negative electrode 40 can do.

  In this way, by adopting a configuration in which the Cockcroft-Walton circuit is branched into the positive side branching portion 28A and the negative side branching portion 28B, each having a different number of booster circuit stages, the absolute value of the voltage applied to the negative electrode 40 is changed to the positive polarity 30. It can be made smaller than the absolute value of the voltage applied to. In this manner, the voltage immediately before the corona discharge start voltage can be applied to both the positive electrode 30 and the negative electrode 40. When the charged body T is passed between the positive electrode 30 and the negative electrode 40 in a state where the voltage just before the corona discharge start voltage is applied in this way, between the charged body T and the positive electrode 30 or between the charged body T and the negative electrode 40. 40, the density of the electric lines of force increases and a corona discharge that protrudes is generated, and the electrostatic energy of the charged body T can be consumed. The area where the density of the electric lines of force increases and the corona discharge that protrudes is generated mainly on the surface of the positive electrode 30 or the negative electrode 40, but when the charged body T has a protruding portion, Such corona discharge also occurs on the surface.

  By passing the charged body T between the positive electrode 30 and the negative electrode 40 which are maintained in a state where the voltage just before the corona discharge start voltage is applied, the change in the electric field between the two is propagated at the speed of light. Can do. For this reason, even if the charged body T is passed between the positive electrode 30 and the negative electrode 40 at a high speed, the protruding corona discharge is surely generated, and the charge removing process of the charged body T can be reliably performed. In this way, the charged body neutralizing device 10 according to the present embodiment is extremely convenient in that it can surely remove a large amount of charged bodies T in a short time.

  In addition, although the voltage just before the corona discharge start voltage is applied to the positive electrode 30 and the negative electrode 40, a protruding corona discharge is generated only when the charged member T is allowed to pass through. The protruded corona discharge is intermittently generated, and the amount of ozone generated due to the protruded corona discharge can be minimized. Therefore, it is advantageous in that the adverse effect of ozone on the surrounding environment of the charged body neutralizing device 10 can be reduced.

(Second Embodiment)
In the present embodiment, the number of booster circuit stages of the Cockcroft-Walton circuit as the DC voltage amplifier circuit 28 is equal between the positive branching portion 28A and the negative branching portion 28B, but corona discharge is generated between the positive electrode 30 and the negative electrode 40. A circuit configuration for equalizing the scale is adopted. In this embodiment, a positive-side current limiting resistor 50 and a negative-side current limiting resistor 52 for limiting the amount of current supplied to each electrode are disposed between the Cockcroft-Walton circuit and the positive electrode 30 and the negative electrode 40. The configuration was adopted.

  Here, since the negative-side current limiting resistor 52 has a larger electrical resistance value than the positive-side current limiting resistor 50, the absolute value of the voltage supplied to the Cockcroft-Walton circuit, the positive electrode 30 and the negative electrode 40 is If they are the same, the absolute value of the supply current to the negative electrode 40 is smaller than the absolute value of the supply current to the positive electrode 30. By disposing such positive electrode side current limiting resistor 50 and negative electrode side current limiting resistor 52, the absolute value of the voltage supplied to positive electrode 30 and negative electrode 40 can be made equal, and the electric field in positive electrode 30 and negative electrode 40 can be made equal. This is advantageous in that corona discharge without excessive ozone generation can be performed on both the positive electrode 30 and the negative electrode 40 while maintaining the above balance.

  The configuration of the charged body static eliminator 10 in this embodiment is such that the absolute value of the voltage boosted by the Cockcroft-Walton circuit as the DC voltage amplifier circuit 28 is equalized between the positive electrode 30 and the negative electrode 40, and the electrical resistance value is Except for the configuration in which the different positive-side current limiting resistor 50 and negative-side current limiting resistor 52 are arranged, the same structure as that of the charged body static elimination apparatus 10 in the first embodiment can be used. The detailed explanation here is omitted by using.

  In the first embodiment, the scale of corona discharge is made equal between the positive electrode 30 and the negative electrode 40 by adjusting the voltage supplied to the positive electrode 30 and the negative electrode 40 (applying voltages having different absolute values). In other words, it is the adjustment of the electric force line density on the surface of the linear body forming the electrode. On the other hand, in this embodiment, the scales of corona discharge in the positive electrode 30 and the negative electrode 40 are made equal by adjusting the amount of current supplied to the positive electrode 30 and the negative electrode 40 (supplying current amounts having different absolute values from each other). is doing. In other words, it is the adjustment of the amount of energy supplied to the electrodes.

  Thus, in 1st Embodiment and 2nd Embodiment, the structure which adjusts the electric force line density in the surface of the linear body which forms the positive electrode 30 and the negative electrode 40, and the energy supply to the positive electrode 30 and the negative electrode 40 Although the configuration differs from the configuration for adjusting the amount, the configuration achieves a common purpose of adjusting the scale of corona discharge in the positive electrode 30 and the negative electrode 40. In addition, the scale of corona discharge here can be prescribed | regulated by the generation amount of ozone by corona discharge, for example.

Next, a method for neutralizing the charged body T using the charged body neutralizing apparatus 10 according to the second embodiment will be described. Here, the case where the charge removal process of the positively charged charged body T is performed will be described.
When a switch (not shown) of the charged body neutralizing device 10 is turned on, the commercial power supplied from the power supply unit 22 is supplied to the control circuit 24, the piezoelectric transformer 26, the DC voltage amplification circuit 28, the positive current limiting resistor 50, and the negative current. With the limiting resistor 52, the scale of the corona discharge in the positive electrode 30 and the negative electrode 40 can be adjusted.

  When a charged body T is passed between the positive electrode 30 and the negative electrode 40 to which a voltage equal to or higher than the voltage just before the corona discharge start voltage is passed using a transport robot (not shown), the potential of the charged body T The electric field between the positive electrode 30 and the negative electrode 40 changes, and the density of the electric lines of force increases between the charged body T and the negative electrode 40, causing a protruding corona discharge. As a result of the corona discharge protruding between the charged body T and the negative electrode 40 in this way, the electrostatic energy of the charged body T is consumed, and the charged body T is finally subjected to a charge removal process. Since the reaction speed when the electric field changes is performed at the speed of light, even if the charged body T is passed between the positive electrode 30 and the negative electrode 40 at a high speed, the charged body T is surely neutralized. be able to.

  In FIG. 2, the charged body T is passed between the positive electrode 30 and the negative electrode 40 in a direction orthogonal to the plane of the paper (direction from the front side of the paper to the back side of the paper and from the back side of the paper to the front side of the paper). However, the direction in which the charged body T is passed between the positive electrode 30 and the negative electrode 40 is not limited to this direction. In addition to the passing direction shown in FIG. 2, the charged body T may pass between the positive electrode 30 and the negative electrode 40 in a direction inclined with respect to the paper surface.

  Further, FIG. 2 shows a state in which the charged body T passes through an intermediate position between the positive electrode 30 and the negative electrode 40, but when the charged body T is positively charged as in the present embodiment. The corona discharge which protruded between the negative electrode 40 and the charging body T can be more effectively performed by passing the position close | similar to the negative electrode 40 as much as possible between the positive electrode 30 and the negative electrode 40. For the same reason, when the charged body T is negatively charged, it is preferable to pass the charged body T between the positive electrode 30 and the negative electrode 40 as close to the positive electrode 30 as possible.

  As described above, the charged body neutralizing device 10 and the charged body neutralizing method using the same have been described in detail based on the present embodiment, but the charged body neutralizing device 10 and the charged body neutralizing method using the same in the present invention are technical. The range is not limited to the embodiment shown above. For example, in the second embodiment, a configuration in which the positive electrode side current limiting resistor 50 and the negative electrode side current limiting resistor 52 are electrically connected to the positive electrode 30 and the negative electrode 40 has been described, but only the negative electrode side current limiting resistor 52 is described. It is also possible to adopt a form in which is provided. This is advantageous in that the arrangement of the positive-side current limiting resistor 50 can be omitted while realizing a corona discharge state in the positive electrode 30 and the negative electrode 40 similar to those of the second embodiment.

  In the first and second embodiments, when a voltage higher than the voltage immediately before the corona discharge start voltage is applied to the positive electrode 30 and the negative electrode 40, the positive electrode 30 and the negative electrode 40 are always in a state where corona discharge is performed. Become. However, if the voltage applied to the positive electrode 30 and the negative electrode 40 is not extremely higher than the voltage immediately before the corona discharge start voltage, the corona discharge continuously generated in the positive electrode 30 and the negative electrode 40 is so-called without generation of ozone. It can be a weak corona discharge. If the charged body T is passed between the positive electrode 30 and the negative electrode 40 where such a weak corona discharge is generated, even if the charged body T has little electrostatic energy, a protruding corona discharge is generated. This is advantageous in that the electrostatic energy of the charged body T can be surely consumed and the charge removal process of the charged body T can be performed reliably.

  In addition to such a voltage application state that always causes a weak corona discharge in the positive electrode 30 and the negative electrode 40, when it is clear that the electrostatic energy of the charged body T is sufficiently high, the positive electrode 30 and the negative electrode A voltage immediately before the corona discharge start voltage may be applied to 40. According to such a voltage application state, a weak corona discharge does not occur in the positive electrode 30 and the negative electrode 40, and only when the charged body T is passed between the positive electrode 30 and the negative electrode 40, a protruding corona discharge is generated. Is advantageous in that it can be generated.

  Moreover, the form which combined suitably the structure demonstrated in Embodiment 1, 2 demonstrated above and the said modification can also be employ | adopted.

10 Charged body static neutralizer,
20 power supply device, 22 power supply unit, 24 control circuit, 26 piezoelectric transformer,
28 DC voltage amplifier circuit, 28A positive side branch, 28B negative side branch,
30 positive electrode, 40 negative electrode, 50 positive current limiting resistor, 52 negative current limiting resistor,
T charged body

Claims (3)

A power supply device, and a positive electrode and a negative electrode electrically connected to the power supply device and arranged in parallel at a necessary interval;
The positive electrode and the negative electrode are formed of linear bodies having the same shape,
The voltage applied to at least the negative electrode of the positive electrode or the negative electrode is a voltage capable of corona discharge and maintained in a predetermined range in which the amount of ozone generated by the corona discharge does not become excessive ,
Between the negative electrode and the power supply device, a negative-side current limiting resistor for limiting the amount of current supplied to the negative electrode is electrically connected,
A positive-side current limiting resistor for limiting the amount of current supplied to the positive electrode is electrically connected between the positive electrode and the power supply device, and the electric resistance value of the negative-side current limiting resistor is A charged body static eliminator characterized by being larger than the electric resistance value of the positive current limiting resistor . The positive electrode and the negative electrode are each electrically connected to the power supply device via a DC voltage amplification circuit,
The charged body static eliminator according to claim 1, wherein an absolute value of a voltage applied to the negative electrode is smaller than an absolute value of a voltage applied to the positive electrode. The charged body static eliminator according to claim 1 or 2 , wherein the predetermined range has an ozone concentration of 0.1 ppm or less at a position 30 cm away from each of the positive electrode and the negative electrode.

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