JP5276691B2 - Static eliminator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a static eliminating apparatus, capable of performing monitoring of produced ion quantities and monitoring of ion balance without complicating the circuit structure. <P>SOLUTION: A current I<SB>1</SB>between a static eliminating bar 4 and a GND plate 10 can be indirectly detected by a potential difference V<SB>1</SB>of a first resistor R<SB>1</SB>. A difference in quantity between positive and negative ions which have reached a frame ground FG on a work side can be indirectly detected by a current I<SB>2</SB>passing through a second resistor R<SB>2</SB>, or a potential difference V<SB>2</SB>of the second resistor R<SB>2</SB>. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

The present invention relates to a static eliminator for static elimination, that is, static elimination, for controlling static electricity in air.

Static electricity removal (static elimination) is performed to control static electricity in the air, such as cleaning in a clean room and preventing static charge of airborne particles. For this non-contact static elimination, a corona discharge ionization device, that is, a static elimination device, is used. It is used a lot.

In order to ensure static elimination by the static eliminator, that is, a desired effect, it is necessary to balance the positive and negative ion generation amounts by the discharge of the electrode needle or the static eliminator included in the static eliminator equally.

The invention disclosed in Japanese Patent Laid-Open No. 3-266398 is caused by the difference between the amount of positive ions generated and the amount of negative ions generated by disposing a current detection electrode between the positive charge removal bar and the negative charge removal bar. It has been proposed to maintain ion balance by detecting ion current.

The invention disclosed in Japanese Patent Application Laid-Open No. 8-78183 detects an effective static elimination current that generates ions that can substantially contribute to static elimination of a workpiece, among currents flowing between a positive elimination bar and a negative elimination bar. Therefore, it has been proposed to control the amount of positive and negative ions that can substantially participate in static elimination.

The following can be said by reconsidering the conditions necessary for static elimination of the workpiece. First, it is possible to confirm that a predetermined amount of ions are generated by the discharge, and second, to maintain ion balance in the vicinity of the workpiece. By satisfying these two conditions, the desired static elimination effect can be ensured.

Accordingly, a first object of the present invention is to provide a static eliminator capable of monitoring the above two. It is a further object of the present invention to provide a static eliminator capable of achieving the first object without complicating the circuit configuration of the static eliminator. Another object of the present invention is to provide a static eliminator capable of easily confirming the static elimination state. Still another object of the present invention is to provide a static eliminator that allows easy confirmation of the amount of ion production and ion balance.

According to the present invention, the technical problem is that, according to the present invention, an electrode needle that generates ions, a high-voltage generation circuit that supplies a voltage to the electrode needle , and an ion current corresponding to the amount of ions in the vicinity of the electrode needle are detected. A first detection means for detecting an ion current from the field ground of the work in accordance with an ion balance in the vicinity of the work, and a plurality of positive sides on both sides of the central light emitting element. A display unit that has an odd number of light emitting elements in which a light emitting element and a plurality of negative side light emitting elements are arranged in a line, and displays the ion generation amount of the electrode needle and the static elimination state of the workpiece by the odd number of light emitting elements When the ion generation amount of the electrode needle is displayed on the display unit , each of the odd number of light emitting elements emits a detection value based on the first signal received from the first detection means. For pre-use In contrast to the plurality of thresholds that is, it controls the light emission operation of the plurality of positive side of the light emitting element and the plurality of negative-side of the light emitting device to recognize the extent of the ion generation amount of positive and the electrode needle to contrast, in the case of displaying the neutralization state of the work by the display unit, the detection value based on the second signal received from said second sensing means, in order to emit the odd number of light emitting elements each The plurality of positive-side light-emitting elements, the plurality of negative-side light-emitting elements, and the central light-emitting element emit light so that the degree of charge removal state of the workpiece can be recognized in comparison with a plurality of threshold values prepared in advance. It is achieved by providing a static eliminator characterized by comprising control means for controlling the operation.

The above and other objects and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments of the present invention.

  As described above, according to the present invention, it is possible to monitor the ion generation amount and the ion balance.

It is a circuit block diagram of the pulse AC type static elimination apparatus of 1st Example. (A) shows the state of the current flowing through the first resistor, and (b) is a diagram in which positive and negative detection values are plotted with time on the horizontal axis. (B) shows an example of control to reduce the amount of negative ions generated by changing the pulse width on the positive side and the negative side, and (b) shows the positive control with a constant pulse width on the negative side. (C) shows a control example that reduces the amount of negative ions generated by reducing the side pulse width. (C) Fix the negative on-pulse width and vary the positive on-pulse and the negative off-pulse width linked to it. Thus, a control example for relatively increasing the amount of negative ions will be shown. It is a figure for demonstrating setting the LED display means contained in a pulse AC type static elimination apparatus to a 1st display mode, and displaying a static elimination state. It is a figure for demonstrating setting the LED display means contained in a pulse AC type static elimination apparatus to a 2nd display mode, and displaying an ion production amount. It is a partial circuit block diagram which shows the modification of the circuit structure of the pulse AC type static elimination apparatus of FIG. It is a circuit block diagram of a pulse DC type static elimination apparatus as a modification. It is a partial circuit block diagram which shows the modification of the circuit structure of the pulse DC type static elimination apparatus of FIG.

FIG. 1 shows a pulse AC type static eliminator 1, which is supplied with a high voltage alternately from the positive and negative high voltage generation circuits 2 and 3 to the electrode needles or the static eliminator bar 4. Polar ions, that is, positive and negative ions are generated alternately. Both the positive and negative high voltage generation circuits 2 and 3 include a self-excited oscillation circuit 7 connected to the primary coil of the transformers 5 and 6 and a booster circuit 8 connected to the secondary coil, such as a double rectifier circuit. Including. A protective resistor 9 is provided between the high voltage generation circuits 2 and 3 and the charge removal bar 4.

A ground (GND) plate 10 is provided near or around the static elimination bar 4, and the GND plate 10 is connected to a work-side ground, that is, a frame ground FG through a conductor 11. Two resistors R1 and R2 are provided in series. Specifically, the first resistor R1 is provided on the GND plate 10 side, and the second resistor R2 is provided on the frame ground FG side. A conductor 12 connects the first resistor R1 and the second resistor R2 to the ground-side ends of the secondary coils of the positive and negative transformers 5 and 6.

The current I1 between the static elimination bar 4 and the GND plate 10 can be indirectly detected by the potential difference V1 of the first resistor R1. Further, the difference between the amount of positive and negative ions reaching the work-side frame ground FG can be indirectly detected by the current I2 passing through the second resistor R2, that is, the potential difference V2 of the second resistor R2. Therefore, the degree of discharge by the static elimination bar 4, that is, the amount of ions generated by the static elimination bar 4 can be detected by the potential difference V1 of the first resistor R1, thereby grasping the performance degradation or the efficiency degradation of the static elimination bar 4. In addition to this, it is possible to know the balance between the positive and negative ion generation amounts generated by the static elimination bar 4.

On the other hand, the ion balance in the vicinity of the workpiece can be known from the potential difference V2 of the second resistor R2.

For example, the potential difference V1 of the first resistor R1 is detected by the ion current detection circuit 14, and this detection data is input to the CPU 15, and the potential difference V1 becomes extremely small or decreases with time. When it becomes smaller, it is sufficient to notify the operator by means of alarm means or display means 16 because of abnormal discharge. Examples of this type of discharge abnormality include a case where dust accumulates on the charge removal bar 4.

In addition, for example, the potential difference V2 of the second resistor R2 is detected by the ion current detection circuit 14, and this detection data is input to the CPU 15 so that the ion balance in the vicinity of the work can be maintained. The positive and / or negative supply voltage may be changed or the pulse width may be changed. At the same time, the fact that the ion balance is not maintained may be notified to the operator through the alarm means or the display means 16.

Further, for example, when the potential difference V1 of the first resistor R1 and / or the potential difference V2 of the second resistor R2 is extremely large, this is detected by the abnormal discharge current detection circuit 17 and input to the CPU 15, for example, 4 and the GND plate 10 or between the static elimination bar 4 and the work, a short circuit has occurred and an abnormal discharge has been generated, so that an emergency light is turned on or an alarm sound is sounded by the alarm means or the display means 16. The alarm may be issued to the user or the operator.

By detecting the potential difference V1 of the first resistor R1 by the ion current detection circuit 14, the following can be monitored. FIG. 2A shows the potential difference V1 of the first resistor R1, that is, the change in the current I1 between the static elimination bar 4 and the GND plate 10 is monitored. In FIG. 2A, the part indicated by the arrow B is an inductive component.

The current value at the point indicated by the arrow A, which is no longer affected by the inductive component, is A / D converted and captured as I1, and the current value I1 is traced over time, so that the current value as shown in FIG. When the decrease in I1 increases, it can be displayed on the display LED 16 as will be described later, assuming that the neutralization bar 4 has become contaminated or dirty.

Further, the ion balance of the ion generation amount can be known by comparing the positive current value I1 or I2 with the negative current value I1 or I2. When there is a difference between the positive current value I1 or I2 and the negative current value I1 or I2, as shown in FIG. 3, the positive high voltage generation circuit 4 and / or the negative high voltage generation circuit 6 Then, a control signal is output from the CPU 15 so as to keep the ion balance of the ion generation amount. As control by this, for example, the duty ratio of the control pulse may be changed.

FIG. 3 shows control signals when there are relatively many positive ions and relatively few negative ions. In the case of (a) in FIG. 3, control is shown in which the amount of negative ions is relatively increased by changing both the positive and negative pulse widths. Specifically, in response to the result that the number of positive ions is relatively large and the number of negative ions is relatively small, assuming that the period is fixed, the pulse width for generating positive ions is reduced and negative ions are generated. To increase the pulse width.

In the case of (b) in FIG. 3, the negative pulse width (cycle) is fixed, the positive pulse is turned on in conjunction with the negative pulse being turned off, and the positive pulse width is reduced. This shows control for relatively increasing the amount of negative ions. In the case of (c) in FIG. 3, the negative on-pulse width is fixed, the positive on-pulse and the negative off-pulse width linked to it are variable, and the positive on-pulse width and linked to it. The amount of negative ions can be relatively increased by decreasing the negative on-pulse width.

4 and 5 show a part of the display unit 19 of the static eliminator 1. The display unit 19 is provided with display means 16 called an ion monitor. The display means 16 includes seven light emitting elements or LEDs 21 to 27, and these LEDs 21 to 27 change display colors between the first display mode (FIG. 4) and the second display mode (FIG. 5). It has become. That is, the ion monitor display means 16 is switched between the first display mode and the second display mode by a user's manual operation.

The ion monitor display means 16 also includes a minus (−) display 28 on the leftmost LED 21 and a plus (+) display 29 on the rightmost LED 27.

The first display mode (FIG. 4) is intended to display the static elimination state in the vicinity of the workpiece. Further, the second display mode (FIG. 5) is intended to display the ion generation state or the ion generation amount.

The display colors of the LEDs 21 to 26 in the first display mode will be described with reference to FIG. 4. In the first display mode, red (LED 21), yellow (LED 22), green (LED 23) sequentially from left to right. ), Green (LED 24), green (LED 25), yellow (LED 26), and red (LED 27). That is, in the first display mode, the ion monitor display means 16 has green (LEDs 23, 24, 25) generally recognized as a color meaning safety in the central portion of the plurality of LEDs arranged side by side, Next to this green, there is yellow (LEDs 22, 26), which is generally recognized as a color that means attention, and red (LEDs 21, 27), which generally means danger, at both ends.

That is, in the first display mode, red, yellow, green, green, green, yellow, and red can be developed from left to right, and (-) is displayed on the leftmost red, and the red on the right. (+) Is written on the top.

When the first display mode of FIG. 4 is selected, the (+) or (−) side LED emits light according to the charge amount on the positive side or negative side of the workpiece. As the ion balance approaches zero, one of the central LEDs 23 to 25 emits green light, and finally the central LED 24 emits green light to indicate that the static elimination has been completed. . As can be easily understood by those skilled in the art, such a display form prepares “threshold values” for causing the LEDs 21 to 27 to emit light, and compares these “threshold values” with detected values. This is possible.

The display colors of the LEDs 21 to 26 in the second display mode will be described with reference to FIG. 5. In the second display mode, green (LED 21), green (LED 22), yellow (LED 23) in order from left to right. ), Red (LED 24), yellow (LED 25), green (LED 26), and green (LED 27). That is, in the second display mode, the ion monitor display means 16 displays green (LEDs 21, 22, 26, 27, which are generally recognized as safety colors at the left end portion and the right end portion of the plurality of LEDs arranged side by side. Next to this green, there is yellow (LEDs 23, 25), which is generally recognized as a color meaning attention, and there is a red (LED 24), generally meaning danger, in the center.

In other words, in the second display mode, green, green, yellow, red, yellow, green, and green can be developed from left to right, and (-) is written on the leftmost green, and the rightmost green. (+) Is written on the top.

When the second display mode of FIG. 5 is selected, the magnitude of the amount of ions generated by the charge removal bar 4 can be known. That is, the amount of positive ions generated is displayed on the right side of the ion monitor display means 16, and the amount of negative ions generated is displayed on the left side of the ion monitor display means 16. When the amount of ions generated is sufficient, the LEDs 21 and 27 at the right end or the left end develop a green color, and as the amount of generated ions decreases, the LEDs 22, 23 or 26, 25 on the center side also become green or When the color is yellow and the amount of generated ions is reduced to an insufficient amount, the central LED 24 is colored red. As can be easily understood by those skilled in the art, such a display form prepares “threshold values” for causing the LEDs 21 to 27 to emit light, and compares these “threshold values” with detected values. This is possible.

The user can know the amount of positive and negative ions produced by viewing the display in the second display mode, and can visually recognize the difference between the amount of positive ions produced and the amount of negative ions produced. It is possible to know the balance of generated ions.

Drawings subsequent to FIG. 6 exemplify modified examples of the discharge-type static eliminator 1. In the description of these modified examples, the same elements as those described above are denoted by the same reference numerals, and the description thereof will be given. Is described below, and the characteristic part of each modification will be described below.

FIG. 6 shows a modification of the circuit configuration of the pulse AC type static eliminator 1 (FIG. 1) described above. In the pulse AC type static eliminator 30 of FIG. 6, the ground side end of the secondary coil of the positive transformer 5 and the ground side end of the secondary coil of the negative transformer 6 are individually independent. 1 is different from the static eliminator 1 of FIG. 1 in that it is connected between the first resistor R1 and the second resistor R2, and is otherwise the same as the static eliminator 1 of FIG.

FIG. 7 shows a pulse DC type static eliminator 40. The DC type static eliminator 40 includes a pair of electrode needles or static elimination bars 4a and 4b, and positive ions are continuously generated from one static elimination bar 4a. Negative ions are continuously generated from the other static elimination bar 4b. In the static eliminator 40, the ground-side ends of the secondary coils of the positive and negative transformers 5 and 6 are connected by the conductor 12.

Even in the pulse DC type static eliminator 40, the above description with reference to FIGS. 1 to 5 is substantially the same, and the display unit 16 can be used to display the amount of ion generation and the static elimination state. .

FIG. 8 shows a modification of the circuit configuration of the pulse DC type static eliminator 40 of FIG. In the pulse DC type static eliminator 41 of FIG. 8, the ground side end of the secondary coil of the positive transformer 5 and the ground side end of the secondary coil of the negative transformer 6 are individually independent. 7 is the same as the static eliminator 40 in FIG. 7 except that it is connected between the first resistor R1 and the second resistor R2.

DESCRIPTION OF SYMBOLS 1 Pulse AC type static elimination apparatus 2 Positive side high voltage generation circuit 3 Negative side high voltage generation circuit 4 Static elimination bar 5 Positive side transformer 6 Negative side transformer 10 GND plate 14 arrange | positioned in the vicinity of static elimination bar Ion current detection circuit 15 CPU
16 Display means R ₁ First resistor R ₂ Second resistor FG Work field ground

Claims (8)

An electrode needle for generating ions;
A high voltage generation circuit for supplying a voltage to the electrode needle;
First detection means for detecting an ion current according to the amount of ions in the vicinity of the electrode needle;
A second detection means for detecting an ion current from the field ground of the work according to the ion balance in the vicinity of the work;
A plurality of positive-side light-emitting elements and a plurality of negative-side light-emitting elements are arranged in a line on both sides of the central light-emitting element, respectively, and the odd-numbered light-emitting elements allow the electrode needle A display unit for displaying the amount of ion generation and the static elimination state of the workpiece;
When the ion generation amount of the electrode needle is displayed on the display unit, a detection value based on the first signal received from the first detection unit is used to cause each of the odd number of light emitting elements to emit light. The light-emitting operations of the plurality of positive-side light-emitting elements and the plurality of negative-side light-emitting elements so that the degree of positive / negative ion generation amount of the electrode needle can be recognized in comparison with a plurality of threshold values prepared in advance. While controlling
When displaying the static elimination state of the workpiece on the display unit, a detection value based on the second signal received from the second detection means is prepared in advance to cause each of the odd number of light emitting elements to emit light. The light emitting operation of the plurality of positive side light emitting elements, the plurality of negative side light emitting elements, and the central light emitting element is controlled so that the degree of the static elimination state of the workpiece can be recognized in contrast to the plurality of threshold values. Control means to
The static eliminator characterized by including. The control means includes
The detection value based on the first signal received from the first detection means is compared with the first and second threshold values for recognizing that the positive and negative ion generation amounts are predetermined amounts, respectively. When the positive and negative ion generation amounts are a predetermined amount, the light emitting operation of the light emitting elements at both ends of the odd number of light emitting elements is controlled, and when either the positive or negative ion generation amount is not the predetermined amount, 2. The static eliminator according to claim 1, wherein the light emitting operation of the light emitting element on one side is controlled so that the degree of ion generation can be recognized. The control means includes
When either the positive or negative ion generation amount is not a predetermined amount, the one of the light-emitting elements closer to the central light-emitting element emits light according to the decrease of the one ion generation amount. The neutralization device according to claim 2, wherein the light emission operation of the light emitting element on the side is controlled. The control means includes
When displaying the static elimination state of the workpiece on the display unit, the light emitting device closer to the central light emitting device among the positive light emitting devices emits light according to the decrease in the positive charge amount of the workpiece. The light emitting operation of the positive side light emitting element is controlled, and the negative side light emitting element emits light so that the light emitting element closer to the central light emitting element among the negative side light emitting elements emits light according to a decrease in the negative charge amount of the work. 4. The static eliminator according to claim 1, wherein the light emitting operation of the element is controlled, and the light emitting operation of the central light emitting element is controlled in accordance with the completion of static elimination of the workpiece. 5.   5. The static eliminator according to claim 1, wherein the static eliminator is a pulse AC type device in which positive and negative high voltages are alternately supplied from the high voltage generation circuit to the electrode needle. apparatus.   The display unit includes means for accepting a user operation related to switching between a first display mode for displaying an ion generation amount of the electrode needle on the display unit and a second display mode for displaying a charge removal state of a workpiece on the display unit. The static eliminator according to any one of claims 1 to 5, wherein An abnormal discharge detection circuit for detecting that an excessive current flows through the first resistor and / or the second resistor;
7. The static eliminator according to claim 1, wherein when the abnormal discharge detection circuit detects the excessive current, a warning is issued to the user. 8. The control means changes the color of the light emitting element so that the degree of ion generation can be recognized, and changes the color of the light emitting element so as to recognize the degree of charge removal of the workpiece. The static eliminator according to any one of claims 1 to 7.

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