JP2007095329A - Static eliminator with electrostatic charge polarity indication function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a static eliminator with the indication function which can notify a worker of completion of the static elimination with distinction of the electrical polarity of the electrostatic charge. <P>SOLUTION: The static eliminator provides a contact (1); a discharge section (3) which discharges a static electricity in case of electrostatic charge of the contact (1); a trigger circuit (10, 40) which adjusts the potential level of an incoming signal due to discharge of the discharge section (3), and delivers the resultant signal as an output; a pulse output section (20, 50) which detects the rising or falling edge of the output signal from the trigger circuit (10, 40) depending on the electrical polarity of the electrostatic charge, and outputs the pulse signal with a given timing width; and an indicator (30, 60) which performs different indication depending on the difference in the detected electrical polarity of the electrostatic charge using the incoming pulse signal. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a static eliminator, and more particularly to a static eliminator capable of displaying the fact that neutralization has been performed and the electrical polarity of charging.

  In manufacturing sites of static sensitive devices such as semiconductors, problems such as destruction of devices and malfunction due to generation of static electricity have been reported. That is, if a semiconductor device is destroyed by static electricity in various processes of the production line such as a manufacturing process, an assembly process, an inspection process, and a shipping process, the production yield is directly affected. Therefore, countermeasures against static electricity have become a major issue in terms of production management, and various countermeasures against static electricity have been devised.

  A static eliminator is used as a conventional countermeasure against static electricity. An ionizer, which is a general charge removal device, ionizes and blows out air using corona discharge, and performs charge removal by directly irradiating a charged object with ions. In particular, since the positive and negative ions can be generated by charging the discharge part where the corona discharge occurs to both positive and negative electrodes, it is possible to effectively remove the charged matter regardless of the electric polarity of the charge.

  Patent Document 1 listed below discloses a human-equipped static eliminator including a discharge unit having both positive and negative ionization functions. According to this human-equipped static eliminator, it is possible to eliminate static electricity regardless of the electrical polarity of static electricity carried by a moving worker who cannot be grounded.

There is also a static elimination device having a function of notifying the operator that static elimination has been performed. For example, in Patent Document 2 below, static electricity is discharged when a charged worker touches the discharge means, and the discharge detection means outputs a detection signal, and a predetermined display is displayed on the discharge display means. There has been disclosed a static eliminator that informs an operator of this fact.
JP 2000-311796 A Japanese Patent Laid-Open No. 03-051773

  The static eliminator described in Patent Document 1 has a function of displaying that power is being supplied to the discharge unit, but this display function is for power supply display of a battery or the like used for the power supply, It does not indicate that static elimination has been performed. Therefore, it is insufficient as a function for notifying the operator that the charge removal has been performed.

  In addition, the electrostatic discharge display device described in Patent Document 2 can inform the operator that the charge removal has been performed, but cannot distinguish and display the electrical polarity of the charge, and as a whole work site. There is a problem that it cannot be used as a countermeasure against charging. Since the electrical polarity of charging varies depending on the substance, generally, the charging tendency at the work site is biased. For this reason, in order to effectively eliminate static electricity, not only the individual static charge of the worker, but also the worker's charge status, the material of the material used at the site, etc. are examined, and the worker is charged. It is desirable to prevent this. Therefore, for example, it is effective if the charging frequency and charging polarity of the operator can be recorded.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a static eliminator having a display function capable of notifying an operator that the charge has been eliminated by distinguishing the electrical polarity of charging. There is to do.

  In order to achieve the above object, a static eliminator with a charge polarity display function according to the present invention includes a contact portion, a discharge portion that discharges static electricity when the contact portion is charged, and a signal input by discharge from the discharge portion. A trigger circuit unit that adjusts and outputs the potential level of the signal, and detects the rising or falling of the output signal of the trigger circuit unit according to the electrical polarity of the charging, and outputs a pulse signal having a predetermined time width A pulse output unit and a display unit that performs different display according to the difference in electrical polarity of the charge to be detected according to the pulse signal are provided.

  The trigger circuit includes a first resistor having one end connected to the discharge unit and the other end connected to the first node, one end connected to the first node, and the other end supplied with a power supply voltage. A first level adjusting circuit having a resistor and a third resistor having one end connected to the first node and the other end grounded; one end connected to the discharge unit; and the other end connected to the second node A sixth resistor connected, one end connected to the second node, a seventh resistor to which the power supply voltage is supplied to the other end, and one end connected to the second node and the other end grounded A second level adjustment circuit having an eighth resistor, wherein the pulse output unit senses a fall of the first output signal output from the first node and outputs a first pulse signal. Pulse output circuit and rise of second output signal output from the second node Ri to sense, can comprise a second pulse output circuit for outputting a second pulse signal.

  The first and second pulse output circuits are monostable multivibrators, a resistance ratio of the second resistor to the third resistor is about 10: 1, and the seventh resistor and the eighth resistor The resistance ratio to the vessel can be about 1:10.

  The resistance value of the first resistor is 10 MΩ or more and 1 GΩ or less, the resistance ratio of the first resistor to the second resistor is about 20: 1, and the resistance value of the sixth resistor is 10 MΩ or more. The resistance ratio of the sixth resistor to the eighth resistor may be about 20: 1.

  According to the present invention, it is possible to provide a display function capable of notifying the operator of the fact that the static elimination has been performed and the electrical polarity of the charging by means of presenting the LED and the piezoelectric buzzer. By notifying that the charge removal has been performed, the operator can confirm that the charge removal device is functioning effectively, and can work with peace of mind.

  In addition, by investigating the electrical polarity of the charge displayed by the display function of the present invention for a plurality of workers, the worker can statistically grasp the charge frequency and charge polarity of the workers. Therefore, the investigation result can be effectively used for countermeasures against static electricity in the entire work site.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following drawings, the same and corresponding parts will be described with the same reference numerals.

  FIG. 1 is a block diagram showing a schematic configuration of a static eliminator with a charge polarity display function according to an embodiment of the present invention.

  The static eliminator with a charge polarity display function according to the present embodiment includes a contact portion 1 that contacts a charged human body (hereinafter referred to as a charged object), a discharge portion 3 that performs discharge, a trigger circuit portion 4, and a pulse. An output unit 5 and a display unit 6 are provided. In the figure, a case for housing these is indicated by a broken line.

  The outline of the operation of the static eliminator with charge polarity display function according to the present embodiment will be described as follows. First, when a charged object, for example, the human body 9 is charged, the contact portion 1 that contacts the human body 9 is also charged with static electricity. When the electrostatic potential of the contact portion 1 due to charging exceeds a certain level, corona discharge occurs in the discharge portion 3, and the static electricity charged in the human body 9 is discharged. Due to this discharge, a pulse signal is generated in the circuit connecting the contact portion 1 and the discharge portion 3. Here, the polarity of the potential of the pulse signal is reversed depending on the electrical polarity of the charge of the human body 9. The trigger circuit unit 4 adjusts the potential level of the pulse signal generated by the corona discharge to a potential level that can be processed by the pulse output unit 5, removes noise of the pulse signal, and outputs the pulse signal to the pulse output unit 5. Next, the pulse output unit 5 detects the rising or falling of the input pulse signal (hereinafter also referred to as a trigger pulse) according to the difference in electrical polarity of charging, and the display unit 6 detects a circuit driving pulse. Is output. The display unit 6 converts the circuit driving pulse into sound or light and presents it. In this way, the fact that the charge removal has been performed is presented by two methods according to the difference in the electrical polarity of the charge.

  FIG. 2 is a circuit diagram of the static eliminator with charge polarity display function according to the embodiment of the present invention shown in FIG.

  The trigger circuit unit 4 shown in FIG. 1 is from the first trigger circuit unit 10 and the second trigger circuit unit 40, the pulse output unit 5 is from the first pulse output unit 20 and the second pulse output unit 50, and the display unit 6 is The first display unit 30 and the second display unit 60 are connected to each other in parallel according to the difference in electrical polarity of the detected charge.

  The static eliminator with a charge polarity display function according to the present embodiment can display whether the charge (human body 9) is positively or negatively charged, and the electrical polarity of the charge. Below, the case where a charged material is positively charged first is demonstrated.

  Since the contact portion 1 is formed of a conductive material such as a metal plate, and the human body 9 is in contact with the contact portion 1, when the human body 9 is charged, the contact portion 1 is also charged. When the electrostatic potential of the contact portion 1 due to charging exceeds a certain level, corona discharge occurs in the discharge portion 3, and the static electricity of the human body 9 is discharged. The discharge part 3 is formed in a shape that easily induces corona discharge using a material that easily induces corona discharge such as a metal protrusion.

  The first trigger circuit unit 10 includes a first level adjustment circuit including first to third resistors 11 to 13, and first and second capacitors 14 and 15. The first resistor 11 of the first level adjustment circuit adjusts the potential level of the pulse signal generated by corona discharge to a level that can be processed by the first pulse output unit 20, and the second and third resistors 12, 13 The power supply voltage Vi is divided into resistance ratios of the second and third resistors 12 and 13 to set the input voltage of the pulse output unit. As will be described later, in the present embodiment, the resistance values of the first to third resistors 11 to 13 can alleviate a shock to the human body 9 due to electric shock during discharge, and the first pulse output unit 20 It is desirable to optimize to a value that matches the input signal conditions. The first trigger circuit unit 10 also functions as a low-pass filter for removing noise from the pulse signal input to the first pulse output unit 20. The capacitance values of the first and second capacitors 14 and 15 are desirably determined by the frequency characteristics required of the low-pass filter and the resistance value of the first resistor 11.

  The first pulse output unit 20 includes a first pulse output circuit 21, a time constant setting unit composed of a fourth resistor 22 and a third capacitor 23, and a protection composed of first and second diodes 25 and 26. Circuit.

  The first pulse output circuit 21 receives a pulse signal from the first trigger circuit unit 10 that functions as a trigger pulse, and drives the first light emitting diode 31 and the first piezoelectric buzzer 34 in the first display unit 30. A circuit driving pulse is transmitted. In the present embodiment, 74HC123 which is a monostable multivibrator is used for the first pulse output circuit 21. The first pulse output circuit 21 includes two trigger input terminals Abar and B. The input terminal B is a type that triggers at the rising edge of the signal according to the electrical polarity of the charge of the human body 9, and triggers at the falling edge of the signal. This type of input terminal Abar is used properly.

  Other than during discharging, the power supply voltage Vi divided by the resistance ratio of the second and third resistors 12 and 13 by the first level adjustment circuit is input to the input terminal Abar. When discharge occurs in the discharge unit 3, the first pulse output circuit 21 detects the falling edge of the pulse signal (trigger pulse) due to the discharge, and drives the circuit with a predetermined time width from the first and second output terminals Q and Qbar. Output a pulse. For example, when the 74HC123 is used with the power supply voltage Vi set to 5.0V, that is, the first pulse output circuit 21 that senses the Hi level when the input voltage is 2.2V and senses the Low level when the input voltage is 0.8V is used. In some cases, a voltage of 0.5 V (Low level) divided into a resistance ratio of 10: 1 between the second and third resistors 12 and 13 is input to the input terminal Abar except during discharging. When discharge occurs in the discharge part 3, electrons flow from the discharge part 3, the voltage of the input signal increases from 0.5V to a threshold voltage of 2.2V or higher, and becomes Hi level. After discharging, the input signal returns to 0.5 V and goes to a low level. In this way, the first pulse output circuit 21 senses the fall of the pulse signal from the Hi level to the Low level, and outputs a circuit driving pulse having a predetermined time width from the first and second output terminals Q and Qbar. To do.

  The pulse width of the circuit driving pulse is adjusted by changing the capacitance value of the third capacitor 23 of the time constant setting unit connected between the terminal Cx and the terminal Rx / Cx. For example, if the capacitance value of the third capacitor 23 is 0.1 μF and the resistance value of the fourth resistor 22 is 1 MΩ, the pulse width is about 0.1 sec.

  The input terminal Abar is provided with a protection circuit having first and second diodes 25 and 26. Thereby, destruction of the 1st pulse output circuit 21 by overcurrent is prevented. The power supply voltage Vi is applied to the terminal CLRbar and the terminal Vcc, and the terminal GND is connected to the frame ground 2. The fourth capacitor 24 is connected between the terminal Vcc and the terminal GND.

  The first display unit 30 includes a first light emitting diode 31 and a first piezoelectric buzzer 34. A voltage is applied to the first light emitting diode 31 by a second circuit driving pulse output from the second output terminal Qbar of the first pulse output circuit 21, respectively, and a first circuit driving output from the first output terminal Q is applied. The first piezoelectric buzzer 34 is energized through the transistor 33 by the pulse. While the first and second circuit driving pulses are output from the first and second output terminals Q and Qbar of the first pulse output circuit 21, the first light emitting diode 31 and the first piezoelectric buzzer 34 emit light and sound. Thus, it is possible to notify that the static electricity has been discharged from the discharge unit 3 and the operator (human body 9) has been neutralized. The fifth resistor 32 is used to adjust the voltage applied to the first light emitting diode 31.

  Next, the case where the charged object is negatively charged will be described.

  When the charged object is negatively charged, the signal generated by the discharge is processed by the second trigger circuit unit 40, the second pulse output unit 50, and the second display unit 60. The second trigger circuit unit 40, the second pulse output unit 50, and the second display unit 60 are configured in the same manner as the first trigger circuit unit 10, the first pulse output unit 20, and the first display unit 30, respectively. The difference between the circuits is that the input terminal B of the type that is triggered by a rising signal is used as the input terminal of the second pulse output circuit 51, and the second level constituted by the sixth to eighth resistors 41 to 43. In the adjustment circuit, the resistance ratio of the seventh and eighth resistors 42 and 43 for dividing the power supply voltage Vi (5 V) is 1:10, and a voltage of 4.5 V is applied to the input terminal B except during discharging. It is input.

  3 to 5 are graphs showing simulation results relating to optimization of circuit element values of the static eliminator with charge polarity display function according to the embodiment of the present invention shown in FIG.

  In the present embodiment, the Hi level and Low level of the pulse signal generated by the discharge are sufficient in accordance with the input characteristics of the first and second pulse output circuits 21, 51, ie, 74HC123 (Vi = 5.0V). The resistance values of the resistors 11 to 13, 41 to 43 and the capacitance values of the capacitors 14, 15, 44, and 45 constituting the first and second trigger circuit units 10 and 40 are optimized so that detection is possible. To do. Curves A to C in the figure respectively show pulse signals at nodes A to C in the circuit diagram shown in FIG.

  The simulation conditions are as follows. First, in the circuit diagram shown in FIG. 2, it is assumed that the contact portion 1 is charged to 10 kV, both positive and negative, and a pulse having a pulse width of about 62 μsec is generated at the node C due to the discharge. In addition, the resistance values of the first and sixth resistors 11 and 41 connected to the discharge unit 3 are set to 20 MΩ so that the shock caused by the electric shock to the human body at the time of discharge can be reduced, and the first, second, The capacitance values of the fifth and sixth capacitors 14, 15, 44, and 45 are set to 470 pF in consideration of the frequency of the low-pass filter and the resistance values of the first and sixth resistors 11 and 41. Under the above conditions, the resistance values of the second, third, seventh and eighth resistors 12, 13, 42 and 43 are changed, and the waveforms of the pulse signals at the nodes A to C in the circuit diagram shown in FIG. Obtained by simulation.

  3 and 4 are graphs showing simulation results when the charged object is positively charged and discharge occurs. FIG. 3 shows a case where the resistance values of the second, third, seventh and eighth resistors 12, 13, 42 and 43 are 1 MΩ, 10 kΩ, 10 kΩ and 1 MΩ, respectively, and FIG. 4 shows the second, third, The case where the resistance values of the seventh and eighth resistors 12, 13, 42, and 43 are 1 MΩ, 100 kΩ, 100 kΩ, and 1 MΩ is shown. A curve C shows a pulse signal at the node C generated by discharging from a charged object charged to +10 kV. When the charged object is positively charged, the signal of the curve A in FIGS. 3 and 4 is the trigger signal of the first pulse output circuit 21.

  In FIG. 3, curve A exceeds the threshold voltage (2.2 V) and becomes Hi level for about 30 μsec after discharge. The time of about 30 μsec is not a sufficient time for the first pulse output circuit 21 to sense the input voltage as the Hi level. Therefore, if the pulse signal is not reliably detected as the Hi level, the first pulse output circuit 21 cannot detect the fall of the pulse signal from the Hi level to the Low level.

  On the other hand, in FIG. 4, the curve A exceeds the threshold voltage and becomes Hi level for about 200 μsec after discharge. This time of about 200 μsec is a time sufficient for the first pulse output circuit 21 to sense the input voltage as the Hi level. Therefore, the pulse signal is reliably detected as the Hi level, and the first pulse output circuit 21 can reliably detect the fall of the pulse signal from the Hi level to the Low level.

  FIG. 5 is a graph showing a simulation result when the charged material is negatively charged and discharge occurs. In this example, the resistance values of the second, third, seventh, and eighth resistors 12, 13, 42, and 43 are set to 1 MΩ, 100 kΩ, 100 kΩ, and 1 MΩ, respectively. A curve C shows a pulse signal at the node C generated by discharging from a charged material charged to −10 kV. When the charged object is negatively charged, a signal shown by a curve B in FIG. 5 is a trigger signal of the second pulse output circuit 51.

  In FIG. 5, the curve B falls below the threshold voltage (0.8 V) for about 120 μsec after discharge and becomes a low level. This time of about 120 μsec is a time sufficient for the second pulse output circuit 51 to sense the input voltage as a low level. Therefore, the pulse signal is reliably detected as the Low level, and the second pulse output circuit 51 can reliably detect the rise of the pulse signal from the Low level to the Hi level.

  As a result of the simulation, the resistance values of the first to third and sixth to eighth resistors 11 to 13 and 41 to 43 constituting the first and second trigger circuit units 10 and 40 and the first, second and second The capacitance values of the fifth and sixth capacitors 14, 15, 44, and 45 were determined to desirable values, respectively. The resistance values of the second and third resistors 12 and 13 constituting the first level adjustment circuit are 1 MΩ and 100 kΩ, respectively, and the resistance values of the seventh and eighth resistors 42 and 43 constituting the second level adjustment circuit. Were found to be 100 kΩ and 1 MΩ, respectively. That is, it is desirable to set the resistance ratios of the resistors constituting the first and second level adjusting circuits for dividing the power supply voltage Vi to 10: 1 and 1:10, respectively. Further, as described above, the resistance values of the first and sixth resistors 11 and 41 connected to the discharge unit 3 constituting the first and second level adjustment circuits are the shocks caused by electric shock to the human body during discharge. It is set in the range of 10 MΩ or more and 1 GΩ or less so that it can be moderated, and preferably 20 MΩ. That is, the resistance ratio of the resistor connected to the discharge unit 3 constituting the first and second level adjusting circuits and the resistor having the higher resistance value among the two resistors dividing the power supply voltage Vi is calculated. It is desirable to set it to 20: 1. The capacitance values of the first, second, fifth and sixth capacitors 14, 15, 44 and 45 are determined in consideration of the frequency of the low pass filter and the resistance values of the first and sixth resistors 11 and 41. 470 pF is desirable.

  FIG. 6 is an external view (a front view and a side view) showing an embodiment of a static eliminator with a charge polarity display function according to an embodiment of the present invention.

  The charge removal device with a charging polarity display function shown in FIG. 6 includes a resin case 71 equipped with a circuit board shown in FIG. 2 and a battery for power supply (both not shown), and a band 72. It is a wrist strap type that can be worn on the wrist of a human body. The back surface of the case 71 includes a contact portion 1 formed using a metal plate. The discharge portion 3 formed using a metal discharge screw on the surface of the case 71, the first and second light emitting diodes 31, 61, and first and second piezoelectric buzzers 34 and 64 are provided. The first and second light emitting diodes 31 and 61 have different emission colors from each other in order to distinguish the electrical polarity of charging. The first and second piezoelectric buzzers 34 and 64 have different timbres in order to distinguish the electrical polarity of charging. The case 71 has a size of about 4 cm × 4 cm. By making the static eliminator a cordless wrist strap type without a grounding wire that can be attached to the human body, the operator can immediately confirm that the static eliminator has been removed regardless of the work place and the electrical polarity of the charge. The static eliminator can be used as a monitor for confirming the charging state.

  FIG. 7 is an external view (front view) showing another example of the static eliminator with charge polarity display function according to the embodiment of the present invention.

  The charge removal device with a charge polarity display function shown in FIG. 7 is installed in a fuel dispenser 73 of a filling station, and the discharge part 3 of the circuit shown in FIG. Is. Similar to the embodiment shown in FIG. 6, the static eliminator with charge polarity display function shown in FIG. 7 covers a substrate (not shown) on which the circuit shown in FIG. 2 is mounted with a resin case 71 ′. The first and second light emitting diodes 31 'and 61', and the first and second piezoelectric buzzers 34 'and 64' are provided on the surface of '. The contact portion 1 ′ is provided on the surface of the case 71 ′. By using a static eliminator with a ground wire 8 as a stationary type, it is necessary to reliably remove static electricity from charged objects, such as semiconductor manufacturing and gasoline filling stations, rather than discharging into the air via the discharge unit 3. In this case, the static electricity can be removed more reliably, and the operator can immediately confirm that the charge removal has been performed and the electrical polarity of the charge.

  Although the case where 74HC123 is used at Vi = 5.0V in the first and second pulse output circuits 21 and 51 has been described above, 74HC123 may be used at a voltage other than 5.0V. For example, if the power supply voltage is about 3.0 V, the charge removal device with a charge polarity display function according to the embodiment of the present invention shown in FIG. 6 can be further miniaturized.

  The first and second pulse output circuits 21 and 51 are not limited to 74HC123, and may function as a monostable multivibrator. For example, TLC555 (manufactured by Texas Instruments) can be used.

  Although the case where both the light emitting diode and the piezoelectric buzzer are used in the first and second display units 30 and 60 has been described above, either one may be used. For example, the light emitting diode may be turned on when discharge occurs while the human body is positively charged, and the piezoelectric buzzer may sound when discharge occurs while the human body is negatively charged.

  In addition, although the light emitting diode and the piezoelectric buzzer are used for the display unit that senses that the charge removal has been performed, presentation means such as a liquid crystal display panel and a speaker can also be used.

  In the above, it has been shown that the resistance values of the first to third and sixth to eighth resistors 11 to 13 and 41 to 43 constituting the first and second level adjustment circuits can be determined by simulation. Is not limited to the above values, and the resistance ratio is not limited to 10: 1 and 1:10. The respective resistance values may be set so that the input signal to the monostable multivibrator circuit to be used changes from the Hi level to the Low level or from the Low level to the Hi level due to the discharge.

  The capacitance values of the first, second, fifth, and sixth capacitors 14, 15, 44, and 45 constituting the first and second trigger circuit units 10 and 40 are set to the first and sixth resistors 11 and 11, respectively. However, the capacitance value is not limited to the above value. Any value may be used as long as it functions as a low-pass filter for removing noise of a pulse signal generated by discharge. Further, when the first and second pulse output circuits 21 and 51 can sense the Hi level / Low level of the pulse signal without being affected by noise, a low-pass filter can be eliminated.

  In the above, when the human body is discharged in a positively charged state, the fall of the signal change occurring at the node A is detected, and when the human body is discharged in the negatively charged state, the rising of the signal change occurring at the node B is detected. However, the present invention is not limited to this. When the human body is discharged in a positively charged state, the rise of a signal change occurring in the node A is detected, and when the human body is discharged in a negatively charged state, the node The falling edge of the signal conversion occurring in B may be detected. That is, the terminal B is used in place of the terminal Abar of the first pulse output circuit 21 (74HC123), the rising edge in the signal change (curve A) of the node A shown in FIG. 4 is detected, and a circuit driving pulse is output. You may make it do.

It is a block diagram which shows schematic structure of the static elimination apparatus with a charge polarity display function which concerns on embodiment of this invention. It is a circuit diagram of the static elimination apparatus with a charge polarity display function according to the embodiment of the present invention shown in FIG. It is a graph which shows the simulation result regarding the optimization of the value of the circuit element of the static elimination apparatus with a charge polarity display function which concerns on embodiment of this invention. It is a graph which shows the simulation result regarding the optimization of the value of the circuit element of the static elimination apparatus with a charge polarity display function which concerns on embodiment of this invention. It is a graph which shows the simulation result regarding the optimization of the value of the circuit element of the static elimination apparatus with a charge polarity display function which concerns on embodiment of this invention. It is an external view (a front view and a side view) which shows one Example of the static elimination apparatus with a charge polarity display function which concerns on embodiment of this invention. It is an external view (front view) which shows another Example of the static elimination apparatus with a charge polarity display function which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Contact part 2 Frame ground 3 Discharge part 10, 40 1st and 2nd trigger circuit part 20, 50 1st and 2nd pulse output part 30, 60 1st and 2nd display part 21, 51 1st and 2nd pulse Output circuit 31, 61 First and second light emitting diodes 34, 64 First and second piezoelectric buzzers

Claims (4)

A contact portion;
A discharge part for discharging static electricity when the contact part is charged;
A trigger circuit unit that adjusts and outputs a potential level of a signal input by the discharge from the discharge unit;
According to the electrical polarity of the charging, a pulse output unit that senses the rising or falling of the output signal of the trigger circuit unit and outputs a pulse signal of a predetermined time width;
A charge removal device with a charge polarity display function, comprising: a display unit that performs different display according to the difference in electrical polarity of the charge sensed by the pulse signal. The trigger circuit is
A first resistor having one end connected to the discharge unit and the other end connected to a first node;
A second resistor having one end connected to the first node and the other end supplied with a power supply voltage; and
A first level adjusting circuit having a third resistor having one end connected to the first node and the other end grounded;
A sixth resistor having one end connected to the discharge unit and the other end connected to a second node;
A seventh resistor having one end connected to the second node and the other end supplied with a power supply voltage; and
A second level adjustment circuit having an eighth resistor having one end connected to the second node and the other end grounded;
The pulse output unit is
A first pulse output circuit for detecting a falling edge of a first output signal output from the first node and outputting a first pulse signal;
2. A charge polarity display function according to claim 1, further comprising: a second pulse output circuit that detects a rising edge of the second output signal output from the second node and outputs a second pulse signal. Static eliminator. The first and second pulse output circuits are monostable multivibrators;
A resistance ratio of the second resistor to the third resistor is about 10: 1;
3. The static eliminator with a charge polarity display function according to claim 2, wherein a resistance ratio of the seventh resistor to the eighth resistor is about 1:10. The resistance value of the first resistor is 10 MΩ or more and 1 GΩ or less, and the resistance ratio between the first resistor and the second resistor is about 20: 1,
3. The charging device according to claim 2, wherein a resistance value of the sixth resistor is 10 MΩ to 1 GΩ, and a resistance ratio of the sixth resistor to the eighth resistor is about 20: 1. Neutralizing device with polarity display function.

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