Ionizer

Abstract

The present invention pertains to a method for manufacturing an ionizer (10) provided with: a first electrode (11) for generating positive and negative ions; a second electrode (110) provided so as to correspond to the first electrode (11); a power source (12) for applying a positive voltage and a negative voltage between the first electrode (11) and the second electrode (110); a storage unit (132) for storing the value of a control parameter of the power source (12); and a power source control unit (131) for controlling the power source (12) on the basis of the value of the control parameter. Said method comprises: a control parameter determination step for determining the value of the control parameter by executing operation of the ionizer in a prescribed inert gas atmosphere; and a storage step for storing, in the storage unit, the value of the control parameter as determined in the control parameter determination step.

Description

Static eliminator

[0001] This invention relates to an ionizer that removes static charge accumulated on the draft shield of an electronic balance or on the object being weighed inside the draft shield.

[0002] A static eliminator generally comprises an ion generation unit, a power supply that provides power to the ion generation unit, and a voltage (current) control unit that controls the power supply and includes memory. Such a static eliminator removes static electricity by driving the ion generation unit to irradiate the object to be purged with positive or negative ions. Types of static eliminators include high-voltage application type (Patent Document 1), ultraviolet type, and soft X-ray type (Patent Document 2). Of these, the high-voltage application type static eliminator generates ions by applying a voltage between electrodes. Ultraviolet and soft X-ray static eliminators generate electron beams that are harmful to the human body and therefore must be used in enclosed spaces, but high-voltage application type static eliminators have a low impact on the human body and are safer even if ions irradiated from the ion source come into contact with the human body.

[0003] In electronic balances, if the object being weighed, the weighing pan, or the draft shield becomes charged, a Coulomb force is generated between the object being weighed, the weighing pan, and the draft shield, causing errors in weighing. Therefore, electronic balances equipped with static eliminators (ionizers) have been used conventionally (for example, Patent Document 1). In electronic balances, since human intervention is required for weighing operations, a highly safe corona discharge type static eliminator, a type of high-voltage application device, is often used. Corona discharge type static eliminators generally generate corona discharge in space by applying a high voltage between a pair of electrodes (in most cases, between one electrode and ground; for convenience, this case is also included in "a pair of electrodes" in this application), thereby ionizing the atmosphere and generating charged elements (ions and electrons). In this case, AC type corona discharge type static eliminators continuously generate both positive and negative charged elements by repeatedly reversing the positive and negative signs of the applied voltage. Of the positive and negative charge elements generated in this way, those with the opposite polarity to the charge on the object (the object to be measured, the weighing pan, the windbreak) are attracted to it, thereby discharging the static electricity from the object.

[0004] Japanese Patent Publication No. 2014-178133, Japanese Patent Publication No. 5918571, Japanese Patent Publication No. 2009-004260

[0005] Takashi Miura, "Method for Reducing Static Electricity Generated by Agitation of Granular Materials with Inert Gas - Comparison of Carbon Dioxide and Argon," Special Research Report of the National Institute of Occupational Safety and Health, (Japan), National Institute of Occupational Safety and Health, November 30, 2023, No. 53, pp. 35-38.

[0006] In recent years, the semiconductor and battery sectors have been major growth markets, and research is progressing to maximize the functionality of the materials that make up products in these fields. Weighing of materials is also an important research tool, and it is expected that there will be a need for more precise weighing in the future. Electronic balances used for weighing are usually used in the atmosphere, which contains water (water vapor) and oxygen. However, in an atmospheric pressure environment, there is a risk that the material being weighed may change in quality during weighing. In conventional weighing, the slight change in the material being weighed that occurs in the short time during weighing could be ignored, but in the future, even such slight changes may be considered problematic.

[0007] Possible causes of deterioration of the weighed object during weighing include moisture absorption and oxidation. For samples where deterioration due to moisture absorption or oxidation is a concern, weighing can be considered in a low-humidity environment free of water vapor or in an inert gas atmosphere such as argon or nitrogen gas that does not contain water vapor or oxygen. Similar to measures against moisture absorption and oxidation, measures against the effects of static electricity are also necessary. However, as described in Non-Patent Literature 1, static charge is less likely to occur in an inert gas atmosphere, so conventionally, it has been thought that static elimination is unnecessary when weighing in an inert gas atmosphere.

[0008] However, the present inventors discovered that an inert gas environment does not necessarily solve the effects of static electricity when weighing trace samples. Charge transfer between an inert gas and the object being weighed is unlikely to occur. Therefore, the inert gas is unlikely to cause a charge imbalance in the object being weighed. However, the object being weighed may be charged before being placed in the inert gas environment. In this case, there is no charge transfer between the inert gas and the object being weighed, and the charge imbalance in the object being weighed remains. In fact, the introduction of inert gas reduces the amount of water vapor that induces charge transfer, further strengthening the charge imbalance in the object being weighed. Therefore, the present inventors discovered that static elimination is necessary even when weighing in an inert gas environment.

[0009] Because inert gas and air have different properties in terms of the exchange of electric charges, a static eliminator that operates normally in an air environment may not operate properly in an inert gas environment. In fact, when a static eliminator that operates in an air environment is operated in an inert gas environment, discharge phenomena are sometimes observed, and it has become clear that sufficient static elimination performance cannot be achieved.

[0010] So far, we have taken the example of a static eliminator installed on an electronic balance, but static electricity should also be eliminated in applications other than electronic balances, such as sample preparation after sample weighing. If a static eliminator is used in an inert gas atmosphere, the problem of insufficient static elimination performance will arise for the same reasons as above. Furthermore, spark discharge may occur, creating a potentially dangerous situation.

[0011] The problem that this invention aims to solve is to provide a method for manufacturing a static eliminator that can obtain sufficient static elimination performance in an inert gas atmosphere, and a static eliminator manufactured by this manufacturing method.

[0012] The method for manufacturing a static eliminator according to the present invention, which has been made to solve the above-mentioned problems, is a method for manufacturing a static eliminator comprising: a first electrode that generates positive and negative ions; a second electrode provided corresponding to the first electrode; a power supply that applies a positive voltage and a negative voltage between the first electrode and the second electrode; a memory unit that stores values ​​of control parameters of the power supply; and a power supply control unit that controls the power supply based on the values ​​of the control parameters, and includes: a control parameter determination step that determines values ​​of the control parameters by performing operation of the static eliminator in a predetermined inert gas atmosphere; and a storage step that stores the values ​​of the control parameters determined in the control parameter determination step in the memory unit.

[0013] The terms "positive voltage" and "negative voltage" above refer to the voltage when the potential applied to the other electrode is positive and negative, respectively, with one of the first and second electrodes set as the reference (zero). Furthermore, as mentioned above, in this application, one of the first and second electrodes may be grounded.

[0014] The static eliminator according to the present invention comprises: a first electrode that generates positive and negative ions; a second electrode that is provided corresponding to the first electrode; a power supply that applies a positive voltage and a negative voltage between the first electrode and the second electrode; a memory unit that stores values ​​of control parameters of the power supply in a predetermined inert gas atmosphere; and a power supply control unit that controls the power supply based on the values ​​of the control parameters.

[0015] The inventors of the present application conducted an experiment in an inert gas atmosphere using a conventional static eliminator that operates normally in a standard atmospheric environment, and found that one of the positive and negative charge elements generates significantly more charge than the other. Therefore, when a conventional static eliminator is used in an environment other than the standard atmospheric environment, the charge element that generates more charge is supplied in excess, and the target object is charged with the polarity of that charge element.

[0016] Therefore, the static eliminator according to the present invention includes a memory unit that stores the values ​​of control parameters of the power supply in a predetermined inert gas atmosphere (such as nitrogen gas or argon gas, which are expected to be used). Furthermore, in the method for manufacturing a static eliminator according to the present invention, the values ​​of control parameters of the power supply corresponding to the predetermined inert gas atmosphere are determined by operating the static eliminator in the predetermined inert gas atmosphere. Examples of the control parameter values ​​of the power supply include the magnitude and application time of the positive and negative voltages applied between the first and second electrodes. The combined time of the application of the positive and negative voltages may be considered as the apparent voltage cycle. The determined control parameters are stored in a memory unit provided in the static eliminator.

[0017] This allows the power supply to be controlled using control parameter values ​​corresponding to a specified inert gas atmosphere when using this electrostatic eliminator, thereby preventing one of the positive and negative charge elements from generating significantly more than the other due to the inert gas atmosphere, and achieving sufficient electrostatic elimination performance.

[0018] Fig. 1 is a perspective view showing an electronic balance provided with a static eliminator according to an embodiment of the present invention. Fig. 2 is a schematic configuration diagram showing the static eliminator of the present embodiment. Fig. 3 is an explanatory diagram showing the time change of high voltage output in the static eliminator of the present embodiment. Fig. 4 is an explanatory diagram showing the ion generation cycle in the static eliminator of the present embodiment. Fig. 5 is a diagram showing the results of measuring, with an oscilloscope, the repeated high voltage and back electromotive force generated from a power source.

[0019] An embodiment of a static eliminator according to the present invention will be described with reference to FIGS. 1 to 5. FIG.

[0020] (1) Configuration of the static eliminator of this embodiment The static eliminator 10 of this embodiment is mounted on an electronic balance 20 as shown in Figure 1. In addition to the static eliminator 10, this electronic balance 20 has a weighing pan 21 placed on the top surface of a base 201, an electronic balance operation unit 22 provided in front of the base 201, and a windshield 23 surrounding the weighing pan 21.

[0021] The windshield 23 has a front wall 231 and a rear wall 232, a frame 230 connecting the front wall 231 and the rear wall 232 at their upper ends, and a right door 233, a left door 234, and an upper door 235 supported on the frame 230 so as to be able to open and close. When these three side doors are closed, the space surrounded by these two side walls, the three side doors, and the upper surface of the base 201 forms a windshield space that prevents the generation of gas flows that could cause errors during measurement. The static eliminator 10 is installed on the surface of the rear wall 232 facing the windshield space.

[0022] The electronic balance operation unit 22 is equipped with a display and input devices such as buttons for various operations by the user of the electronic balance 20. The input operations performed on the electronic balance operation unit 22 include setting operations related to the functions of the electronic balance itself, such as zero point adjustment and tare subtraction, as well as operations related to the setting of the static eliminator 10, as described below.

[0023] 2 shows the configuration of the static eliminator 10 of this embodiment. The static eliminator 10 has a needle electrode 11, a ground electrode plate 110, a power source 12, a control unit 13, and a static eliminator input unit 14. The static eliminator 10 itself has the static eliminator input unit 14, and the electronic balance operation unit 22 of the electronic balance 20 also functions as the static eliminator input unit 14. When the static eliminator 10 is manufactured, the manufacturer mainly performs input operations using the static eliminator input unit 14 of the static eliminator 10.

[0024] The static eliminator 10 directly includes one or more discharge needles as the electrode needle 11. The ground electrode plate 110 is grounded. A voltage is applied between the electrode needle 11 and the ground electrode plate 110 (ground) from the power source 12, so that one of the electrode needle 11 and the ground electrode plate 110 functions as the first electrode, and the other functions as the second electrode. Here, the ground electrode plate 110 is used as the reference (zero), and a voltage applied to the electrode needle 11 when the potential is positive is referred to as a "positive voltage," and a voltage applied to the electrode needle 11 when the potential is negative is referred to as a "negative voltage." Note that instead of providing a single electrode needle 11 and applying a voltage between it and the ground electrode plate 110, an electrode pair consisting of two electrodes may be provided, and positive and negative voltages may be applied between the two electrodes, respectively.

[0025] The power supply 12 is composed of a DC power supply 121, a full-bridge circuit 122 with four switch elements, and a transformer 123. This power supply 12 employs a hybrid digital control-alternating current (HDC-AC) system in which the DC voltage output from the DC power supply 121 is converted to an AC voltage by pulse-width modulation (PWM) in the full-bridge circuit 122, and the AC voltage is applied to the primary winding of the transformer 123, thereby intermittently supplying a predetermined positive / negative voltage to the primary winding. A high voltage boosted by the transformer 123 is applied between the electrode needle 11 and the ground electrode plate 110, causing a corona discharge between the electrodes, thereby generating ions. A rest period is provided between each application of the high voltage. Furthermore, periods of repeated application of a positive high voltage and periods of repeated application of a negative high voltage are alternated at a relatively low frequency (i.e., a frequency lower than the frequency at which the positive or negative high voltage is repeatedly applied). The combination of one period during which a positive high voltage is repeatedly applied and one period during which a negative high voltage is repeatedly applied can be considered as an apparent voltage cycle. These voltage controls generate clumps of positive ions and clumps of negative ions, which can be transported far away by the electric field without canceling each other out (see Patent Document 3). The present invention is not limited to the above-described embodiment, and can also be realized by using, for example, a power supply with sine wave high frequency control.

[0026] The control unit 13 controls the operation of the power supply 12 and has a main control unit 131 and a memory unit 132. The control unit 13 is realized by hardware such as a CPU (main control unit 131) and memory (memory unit 132), and software that operates that hardware.

[0027] The main control unit 131 retrieves the control program stored in the storage unit 132, as described later, and then transmits a signal to the power supply 12 to control the operation of the power supply 12 based on the control program.

[0028] The memory unit 132 stores a control program that controls the operation of the power supply 12. Here, the control program controls the application time of the positive voltage and the negative voltage, respectively. Different control programs are created for each of the multiple gas atmospheres in which the static eliminator 10 is used, and these are stored in the memory unit 132. The gas atmosphere in which the static eliminator 10 is used contains at least one type of inert gas, but these may all be inert gas atmospheres, or they may include one or more types of inert gas atmospheres and one or more types of non-inert gas atmospheres. Examples of inert gas atmospheres include nitrogen gas atmospheres and argon gas atmospheres. Examples of non-inert gas atmospheres include air atmospheres and vacuum atmospheres. In the following, the case in which three types of atmospheres, air atmosphere, nitrogen gas atmosphere, and argon gas atmosphere, are used will be described as an example. In this embodiment, the program is stored in the memory unit, but instead, only the values ​​of control parameters such as voltage values, application time, and switching cycle may be stored in the memory unit, and a program called separately from the memory unit, or hardware composed of analog circuits or digital integrated circuits such as FPGAs, may execute control based on the values ​​of these control parameters.

[0029] As mentioned above, the electronic balance control unit 22 performs setting operations related to the functions of the electronic balance 20 itself, as well as operations related to the settings of the static eliminator 10, such as selecting the gas atmosphere to be used from a set of registered gas atmospheres. This electronic balance control unit 22 corresponds to the gas atmosphere selection unit, which will be described later.

[0030] (2) Operations Performed During the Manufacturing of the Neutralizer of the Present Embodiment: Neutralizers used in standard atmospheres eliminate static electricity by ionizing oxygen, water vapor, and the like. However, in environments such as glove boxes, oxygen is purged by introducing only inert gases such as argon or nitrogen to prevent oxidation. A low-humidity environment is required to prevent moisture absorption, and water vapor is also absent. This significantly differs from standard atmosphere, resulting in significantly different ionization rates depending on the gas. In such inert gas environments, no gases generate negative ions; electrons themselves act as negatively charged elements, resulting in an ion balance completely different from that of atmospheric air. Furthermore, static electricity is more likely to be generated in such low-humidity environments, making static elimination during measurement essential. For these reasons, static eliminators tuned for standard atmospheres can be hazardous because spark discharges, rather than corona discharges that generate ions, can occur in inert gas and low-humidity environments. Conventionally, corona discharge ionizers designed for atmospheric environments have been used even in such environments. In addition, static elimination in an argon gas atmosphere is achieved by irradiating strong energy such as X-rays, but this requires consideration of the safety of the equipment and a large capital investment. In this embodiment, a corona discharge type ionizer that can eliminate static in an inert gas environment is provided as a cheaper means of realizing this.

[0031] Traditionally, when manufacturing static eliminators that operate under standard atmospheric conditions, the static eliminators are placed in a manufacturing room to ensure that there is no imbalance between the positive and negative charge elements. To confirm whether static elimination is occurring on objects within an appropriate distance from the static eliminator, a standardized charged plate monitor (CPM) is commonly used to check ion balance by generating a charge between a pair of plates positioned a predetermined distance from the static eliminator. Furthermore, once the control parameters, such as the voltage used to control the static eliminator, are adjusted, they can be used without being affected by minor environmental changes, such as temperature. Therefore, generally (except when used under an inert gas environment, as described below), the process of storing the control parameter values ​​for each static eliminator can be omitted, and previously determined control parameter values ​​can be stored in static eliminators that have not yet been stored. However, the inventors of the present application discovered that when manufacturing a static eliminator that operates in an inert gas environment, the control parameter values ​​stored in an atmospheric pressure environment cannot be used, and it is necessary to store control parameter values ​​for each type of inert gas (note that if the static eliminator is used for strict measurement or development, it is desirable to adjust the control parameter values ​​for each static eliminator even when it is used in an environment other than an inert gas environment).

[0032] Therefore, when manufacturing the static eliminator 10 of this embodiment, the appropriate magnitude and application time of the positive voltage and negative voltage to be applied between the electrode needle 11 and the ground 110 are determined for each inert gas atmosphere (e.g., nitrogen gas atmosphere and argon gas atmosphere) used when using the static eliminator 10, and a process (control program storage process) is performed in which a control program created based on the results is stored in the memory unit 132.

[0033] Referring to Figures 3 and 4, the adjustment of the high voltage in the static eliminator 10 of this embodiment will be described. A PWM-controlled voltage is input to the primary winding of the transformer 123, and the high voltage boosted by the transformer 123 is applied between the electrode needle 11 and the ground electrode plate 110. This generates a corona discharge between these electrodes, which generates ions. A pause is provided between each high voltage application, and a high voltage with a steep fluctuation is repeatedly generated at a frequency of approximately 250 Hz. Furthermore, a period in which a positive high voltage is repeatedly generated and a period in which a negative high voltage is repeatedly generated are provided at a low frequency of 0.5 Hz. The ion balance is adjusted by the magnitude of the positive and negative input voltages and one or both of the durations of the positive and negative voltages. Furthermore, by providing a pause, a negative voltage (separate from the negative high voltage) is generated immediately after the application of the positive high voltage. This negative voltage is also used to adjust the voltage.

[0034] The experimental results are described below. First, the high voltage is a positive voltage V + to +4.16kV, negative voltage V - When a voltage of −1.6 kV was applied to the ion detection probe and the potential was measured, the ion balance value was −410 V.

[0035] Therefore, as shown in Table 1 below, the positive voltage V + and negative voltage V - As the absolute value of V was reduced, the ion balance value, which is the average potential of the ion detection probe, approached 0. - The ion balance value could be adjusted to almost zero when the voltage was -844 V. This ion balance value reflects the ratio of the amount of positive charge generated by the positive charge element to the amount of negative charge generated by the negative charge element, and the smaller the absolute value of the ion balance value, the closer the ratio is to 1.

[0036] So, the positive voltage V + is +4.16kV, negative voltage V -A control program for an argon gas atmosphere can be created and stored in the memory unit 132 so that the voltage at the positive electrode is -844V. In this embodiment, as a result of further research in addition to the above experiments, it was confirmed that ion balance can be achieved by setting the positive electrode voltage in the range of +4.5 kV to +2 kV and the negative electrode voltage in the range of -2 kV to -0.7 kV. It was confirmed that a positive electrode voltage of 3.5 kV or less is preferable, and in this case, the amount of ion generation approaches the optimal value. It is expected that the above voltage range will be affected by the distance between the electrodes. It was confirmed that the above voltage range is particularly effective in the range of 15 mm to 4 mm between the electrodes used in this embodiment. Furthermore, although the procedure for adjusting the voltage value is described in this embodiment, the voltage application time may also be adjusted to achieve ion balance. Since the amount of ion generation increases with increasing application time, the application time may also be set based on the amount of ion generation monitored. In general, to balance the positive and negative charge elements, the absolute values ​​of the negative and positive voltages are generally the same. The reason for the asymmetry between the negative and positive voltages in the present invention is that it was discovered that the negative charge elements can be balanced even when the negative voltage is small. The mechanism by which the negative charge elements can be balanced even when the negative voltage is small is as follows. In this embodiment, an environment filled with an inert gas is targeted. When ionized, the positive charge elements are positive ions of the inert gas with a large mass, and the negative charge elements are electrons. Therefore, the negative charge elements can impart large kinetic energy even with a relatively small voltage. Therefore, from the viewpoint of mobility, it is expected that ions are balanced.

[0037] To investigate why the static eliminator of this embodiment generates more negative charge elements than positive charge elements under an argon gas atmosphere, the repetitive high voltage generated by the power supply 12 was measured using an oscilloscope. The results revealed that a negative high voltage was generated after a single generation of a +4.16 kV positive high voltage, resulting in a discharge (Figure 5). This discharge is thought to be due to the generation of a negative voltage immediately after the generation of the positive high voltage is cut off in the transformer 122 used to generate a high pulse repetitive voltage of several kV in the power supply 12. (Note: Due to the characteristics of the transformer 122 used, a positive voltage is generated immediately after the negative high voltage is cut off, but it is not high enough to generate ions.) The discharge of the negative voltage generates a negative charge element, and this, combined with the negative charge element generated by the discharge from the power supply 12, results in the generation of an excessive number of negative charge elements. Experiments confirmed that the probability of discharge gradually increases from voltages above +2.5 kV.

[0038] It is believed that negative voltage due to the characteristics of the transformer occurs under atmospheric pressure as well as under an argon gas atmosphere. However, under atmospheric pressure, even if the negative voltage occurs, it does not result in discharge, or even if discharge does occur, the amount of negative charge generated is sufficiently small, so that it does not affect the static elimination performance.

[0039] Up to this point, we have explained using an argon gas atmosphere as an example, but by performing the same operation in a nitrogen gas atmosphere or the like, a control program can be created and stored in the memory unit 132.

[0040] (3) Operation of the static eliminator of this embodiment when in use When using the static eliminator 10 of this embodiment, the static eliminator 10 (or the electronic balance 20 having the static eliminator 10) is placed in a specific gas atmosphere (air, nitrogen gas, or argon gas). The user operates an input unit that selects the environment, such as the gas atmosphere and dew point temperature, using the selection means on the operation panel of the static eliminator 10, to select the gas atmosphere, dew point temperature, etc. in which the static eliminator 10 is placed. Then, the main control unit 131 controls the operation of the power supply 12 using the control program. As a result, a positive voltage V suitable for the selected gas atmosphere is generated. + and negative voltage V -A voltage is applied between the electrode needle 11 and the ground electrode plate 110 with a magnitude and application time of , whereby positive charge elements and negative charge elements are generated in approximately equal numbers.

[0041] In this way, in the static eliminator 10 of this embodiment, a positive voltage V + and negative voltage V - A voltage is applied between the electrode needle 11 and the ground electrode plate 110 at a magnitude and application time of , whereby positive and negative charge elements are generated in nearly equal numbers, thereby preventing one of the positive and negative charge elements from being generated in significantly greater amounts than the other, and achieving sufficient static elimination performance.

[0042] (4) Modifications The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, in the above-described embodiment, the static eliminator 10 is installed on the electronic balance 20, but the static eliminator 10 may be installed on a device other than the electronic balance 20, or the static eliminator 10 may be used alone.

[0043] In the above embodiment, when creating the control program to be stored in the storage unit 132, the positive voltage V + and / or a negative voltage V - The magnitude of the voltages was changed, and the time for applying each of these voltages was not changed, but a positive voltage V was applied together with or instead of these magnitudes. + and / or a negative voltage V - The application time of the voltage may be changed.

[0044] In the above embodiment, a control program is created for each of a plurality of gas atmospheres, and the gas atmosphere, dew point temperature, etc. can be selected by operating the input unit 14 at the time of use. However, when the static eliminator is to be used with one specific gas atmosphere, dew point temperature, etc., a control program may be created only for that specific gas atmosphere, dew point temperature, etc., and the selection unit (input unit) for selecting the gas atmosphere, dew point temperature, etc. may be omitted.

[0045] In the above embodiment, the positive voltage V is set so that the ion balance value approaches 0 (corresponding to the ratio of the amount of positive charge element to the amount of negative charge element approaching 1). + and negative voltage V -Instead, the generated positive and negative charge elements were irradiated onto an object (charged body) that had been previously charged positively or negatively, and the positive voltage V + and negative voltage V - By measuring these positive voltages V + and negative voltage V - may be adjusted.

[0046] Aspects It will be apparent to those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0047] (Item 1) A method for manufacturing a static eliminator according to one aspect of the present invention is a method for manufacturing a static eliminator comprising: a first electrode that generates positive and negative ions; a second electrode provided corresponding to the first electrode; a power supply that generates a positive voltage and a negative voltage between the first electrode and the second electrode; a memory unit that stores values ​​of control parameters of the power supply; and a power supply control unit that controls the power supply based on the values ​​of the control parameters, the method comprising: a control parameter determination step that determines values ​​of the control parameters by performing operation of the static eliminator in a predetermined inert gas atmosphere; and a storage step that stores the values ​​of the control parameters determined in the control parameter determination step in the memory unit.

[0048] (Item 6) The static eliminator according to item 6 includes: a first electrode that generates positive and negative ions; a second electrode that is provided corresponding to the first electrode; a power supply that generates a positive voltage and a negative voltage between the first electrode and the second electrode; a memory unit that stores values ​​of control parameters of the power supply in a predetermined inert gas atmosphere; and a power supply control unit that controls the power supply based on the values ​​of the control parameters.

[0049] The inventors of the present application conducted an experiment in an inert gas atmosphere using a conventional static eliminator that operates normally in a standard atmospheric environment, and found that one of the positive and negative charge elements generates significantly more charge than the other. Therefore, when a conventional static eliminator is used in an environment other than the standard atmospheric environment, the charge element that generates more charge is supplied in excess, and the target object is charged with the polarity of that charge element.

[0050] Therefore, in the static eliminator according to paragraph 6, a memory unit is provided in a power supply control unit that controls the power supply during manufacturing of the static eliminator. In the method for manufacturing a static eliminator according to paragraph 1, the static eliminator is operated in a predetermined inert gas atmosphere (such as nitrogen gas or argon gas, which are expected to be used), and the control parameter values ​​of the power supply corresponding to that atmosphere are determined. Examples of the control parameter values ​​include the magnitude and application time of the positive and negative voltages applied between the first and second electrodes. The combined time of the application of the positive and negative voltages can also be considered as the apparent voltage period.

[0051] As a result, when using the static eliminator according to paragraph 6, the power supply can be controlled with the value of the control parameter corresponding to a specified inert gas atmosphere, thereby preventing one of the positive and negative charge elements from generating significantly more than the other due to the inert gas atmosphere, and achieving sufficient static elimination performance.

[0052] (Paragraph 2) The method for manufacturing a static eliminator according to Paragraph 2 is the method according to Paragraph 1, wherein the value of the control parameter includes one of the magnitudes and application times of the positive voltage and the negative voltage, respectively.

[0053] According to the method for manufacturing a static eliminator relating to paragraph 2, by using one (or any two to four) of the magnitude of the positive voltage, the magnitude of the negative voltage, the application time of the positive voltage, and the application time of the negative voltage as the value of the control parameter, it is possible to reliably prevent one of the positive and negative charge elements from generating more electricity than the other, thereby achieving better static elimination performance.

[0054] (Item 3) The method for manufacturing a static eliminator according to item 3 is the method according to item 1 or 2, wherein the control parameter determination step includes a step of determining the magnitude and application time of each of the positive voltage and the negative voltage, which are determined so that the ratio of the amount of positive charge elements to the amount of negative charge elements generated in the specified inert gas atmosphere is within a specified range.

[0055] According to the method for manufacturing a static eliminator relating to paragraph 3, by ensuring that the ratio of the amount of positive charge elements to the amount of negative charge elements generated in a specified inert gas atmosphere is within a specified range, the magnitude and application time of each of the positive voltage and the negative voltage can be appropriately determined so that the ion balance value can approach 0.

[0056] (4) The method for manufacturing a static eliminator according to 4 is the method according to 1 or 2, wherein the control parameter determination step includes a step of removing static electricity by irradiating a charged body that has been charged in advance in the specified inert gas atmosphere with a positive charge element and a negative charge element that are generated by applying the positive voltage and the negative voltage, and measuring the voltage values ​​of the positive voltage and the negative voltage at that time.

[0057] According to the method for manufacturing a static eliminator relating to item 4, by irradiating a positive charge element and a negative charge element onto a charged body that has been charged in advance, and measuring the voltage values ​​of the positive voltage and negative voltage applied between the electrodes when static electricity is removed, these voltage values ​​(the respective magnitudes of the positive voltage and the negative voltage) can be appropriately determined.

[0058] (Paragraph 5) The method for manufacturing an antistatic device according to Paragraph 5 involves storing the values ​​of control parameters in the storage unit for each of several different gas atmospheres, each including at least one type of inert gas atmosphere, in the method according to any one of Paragraphs 1 to 4.

[0059] (Clause 7) The static eliminator according to clause 7 is the static eliminator according to clause 6, further comprising a gas atmosphere selection unit that allows a user to select one of a plurality of different gas atmospheres including at least one type of inert gas atmosphere, the memory unit stores values ​​of the control parameters determined for each of the plurality of different gas atmospheres, and the power supply control unit controls the power supply based on the value of the control parameter corresponding to the gas atmosphere selected by the gas atmosphere selection unit.

[0060] According to the method for manufacturing a static eliminator described in paragraph 5 and the static eliminator described in paragraph 7, by storing the values ​​of control parameters in a memory unit for each of several different gas atmospheres, each containing at least one type of inert gas atmosphere, the static eliminator can be controlled under appropriate conditions for each of those gas atmospheres. In addition to at least one type of inert gas atmosphere, these several gas atmospheres may also include atmospheres other than inert gas atmospheres, such as air or oxygen.

[0061] 10...Static eliminator 11...Electrode needle 110...Ground electrode plate 12...Power supply 121...DC power supply 122...Full bridge circuit 123...Transformer 13...Control unit 131...Main control unit 132...Memory unit 14...Static eliminator input unit 20...Electronic balance 201...Base 21...Weighing pan 22...Electronic balance operation unit 23...Draft shield 230...Frame 231...Front wall 232...Rear wall 233...Right side door 234...Left side door 235...Top door

Claims

1. A method for manufacturing a static eliminator comprising: a first electrode that generates positive and negative ions; a second electrode provided corresponding to the first electrode; a power supply that applies a positive voltage and a negative voltage between the first electrode and the second electrode; a memory unit that stores control parameter values ​​for the power supply; and a power supply control unit that controls the power supply based on the control parameter values, the method comprising: a control parameter determination step of determining the control parameter values ​​by executing the operation of the static eliminator in a predetermined inert gas atmosphere; and a storage step of storing the control parameter values ​​determined in the control parameter determination step in the storage unit.

2. The method for manufacturing a static eliminator according to claim 1, wherein the value of the control parameter includes one of the magnitude and application time of each of the positive voltage and the negative voltage.

3. The method for manufacturing a static eliminator according to claim 2, wherein the control parameter determination step includes a step of determining the magnitude and application time of the positive voltage and the negative voltage, which are determined so that the ratio of the amount of positive charge elements to the amount of negative charge elements generated in the specified inert gas atmosphere falls within a specified range.

4. The method for manufacturing a static eliminator according to claim 2, wherein the control parameter determination step includes a step of removing static electricity by irradiating a charged body that has been charged in advance in the specified inert gas atmosphere with a positive charge element and a negative charge element that are generated by applying the positive voltage and the negative voltage, and measuring the voltage values ​​of the positive voltage and the negative voltage at that time.

5. The method for manufacturing a static eliminator according to claim 1, wherein in the storage step, values ​​of control parameters are stored in the storage unit for each of a plurality of different gas atmospheres, including at least one type of inert gas atmosphere.

6. A static eliminator comprising: a first electrode that generates positive and negative ions; a second electrode that is provided corresponding to the first electrode; a power supply that applies a positive voltage and a negative voltage between the first electrode and the second electrode; a memory unit that stores values ​​of control parameters of the power supply in a predetermined inert gas atmosphere; and a power supply control unit that controls the power supply based on the values ​​of the control parameters.

7. The static eliminator according to claim 6, further comprising a gas atmosphere selection unit that allows a user to select one of a plurality of different gas atmospheres including at least one type of inert gas atmosphere, wherein the memory unit stores values ​​of the control parameters determined for each of the plurality of different gas atmospheres, and the power supply control unit controls the power supply based on the value of the control parameter corresponding to the gas atmosphere selected by the gas atmosphere selection unit.

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