JP2010097805A - Ion generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ion generator, capable of controlling balance between positive and negative ions by controlling positive and negative voltages to be applied to a discharge electrode by a simple circuit structure. <P>SOLUTION: In the ion generator, the discharge electrode 3 is capacitively-coupled to the secondary side of a transformer T1 to the primary side of which alternating voltage is applied by a capacitor C1, diodes D1 and D2 are connected in parallel, and the quantities of positive and negative ions are controlled by opening and closing switches SW1 and SW2 serially connected to the diodes. A voltage shifted to the negative electrode side is applied to the discharge electrode 3 by closing the switch SW1 and opening the switch SW2, whereby negative ions are generated. Reversely, a voltage shifted to the positive electrode side is applied to the discharge electrode 3 reversely by closing the switch SW2 and opening the switch SW1, whereby positive ions are generated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ion generator, and more particularly, to a technique effective when applied to an ion generator used in a static eliminator that removes static electricity from an object.

  According to a study by the present inventor, the ion generator is used in a static eliminator that removes static electricity generated in an object by friction charging, peeling charging, induction charging or the like. In particular, in the electronics industry, it is used to prevent electrostatic breakdown of semiconductors and electronic devices, and device failures due to floating dust such as liquid crystal, wafers, and disks. With respect to such an ion generator, for example, techniques described in Patent Documents 1 to 4 can be cited.

  In Patent Document 1, one end of a secondary winding of a step-up transformer is connected to a discharge electrode, and the other end of the secondary winding is connected to a first transistor for passing a positive current through the secondary winding. Disclosed is a technique for grounding via a parallel circuit with a second transistor for passing a negative current, and increasing or decreasing the secondary current of the step-up transformer by increasing or decreasing the base current of the first and second transistors by a control circuit. Has been.

In Patent Document 2, a positive high voltage generation circuit and a negative high voltage generation circuit are connected to a DC power source via two switches, respectively, and the positive high voltage generation circuit and the negative high voltage generation circuit are connected. A technique is disclosed in which a discharge electrode is connected between output terminals of a voltage generation circuit, and each high voltage generation circuit is composed of two transformers and two voltage doubler rectifier circuits. Further, in Patent Document 3, in addition to the two switches of Patent Document 2, each of two resistors connected between the output terminals of the positive high voltage generating circuit and the negative high voltage generating circuit is connected in parallel. A technology is described in which switches are connected to and these four switches are controlled. Patent Document 4 describes a technique of providing a switch in each of the positive high voltage generation circuit and the negative high voltage generation circuit and controlling the switch.
JP 2003-264097 A JP 2000-58290 A JP 2004-63431 A JP 2008-123912 A

  By the way, as a result of examination by the present inventor regarding the ion generator as described above, the following has been clarified.

  For example, in the technique of Patent Document 1, the control circuit increases or decreases the secondary current of the step-up transformer by increasing or decreasing the base currents of the first and second transistors according to the amount of positive and negative ions generated from the discharge electrode. Adjust the positive and negative ion balance. However, the technique of Patent Document 1 detects the amount of positive and negative ions generated from the discharge electrode of the ion generator itself, senses the charged state of an object different from the ion generator, and according to the charged state. It is not something to control. Further, the peak current of the secondary voltage of the step-up transformer is controlled by increasing or decreasing the base currents of the first and second transistors, and the voltage waveform itself is not shifted to the positive side or the negative side.

  Moreover, since the technique of the said patent documents 2-4 is provided with the transformer in each of the positive polarity high voltage generation circuit and the negative polarity high voltage generation circuit, two transformers are needed for an ion generator, There is a problem in terms of circuit configuration.

  Further, as a conventional technique, there is a method in which a discharge voltage is separately applied to two electrodes, a positive electrode and a negative electrode, but in this conventional method, the distance between the positive electrode and the negative electrode with respect to an object Therefore, there was unevenness of positive and negative ion balance.

  Accordingly, an object of the present invention is to provide an ion generator capable of controlling the positive and negative voltage applied to the discharge electrode and controlling the balance between positive and negative ions with a simple circuit configuration. It is in.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  That is, the outline of a typical one is that by operating the first switch for positive polarity control and the second switch for negative polarity control provided on the high voltage (secondary side of the transformer) in the AC high voltage circuit, The voltage applied to the discharge electrode is controlled to control the positive / negative ion balance.

  Specifically, a configuration having a control circuit that controls the first switch and the second switch connected in parallel to the secondary side of the transformer to which an AC voltage is applied to the primary side according to the charged state of the object When the object is charged positively, the first switch is turned on and the second switch is turned off to generate an alternating voltage waveform shifted to the negative side, and the alternating voltage waveform shifted to the negative side Is applied to the discharge electrode to generate negative ions. Conversely, when the object is negatively charged, the AC voltage is shifted to the positive side by turning on the second switch and turning off the first switch. A waveform is generated, and an AC voltage waveform shifted to the positive electrode side is applied to the discharge electrode to generate positive ions.

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  That is, the effect obtained by a representative one is that by controlling the positive / negative ion balance, it is possible to arbitrarily manipulate a state where there are many positive ions or a state where there are many negative ions, Can be more effectively removed than in the past.

  In addition, since the discharge voltage is applied to one discharge electrode in the present invention as compared with the conventional method in which the discharge voltage is applied separately to the two electrodes, the positive electrode and the negative electrode, the positive polarity and the negative electrode Even in a normal state in which the sex control is not performed, there is no unevenness of positive and negative ion balance due to the distance from the object, and an excellent ion balance can be ensured.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.

(Embodiment 1)
The ion generator of Embodiment 1 of this invention is demonstrated using FIG. 1 and FIG.

  First, the structure of the ion generator of this Embodiment is demonstrated using FIG. FIG. 1 is a circuit diagram showing the configuration of the ion generator of the present embodiment.

  The ion generator of the present embodiment includes an oscillation circuit 1, a control circuit 2, a transformer T1, a capacitor C1, diodes D1 and D2, switches SW1 and SW2, a discharge electrode 3, an electrostatic sensor 4, and the like. In the ion generator of the present embodiment, for example, a step-up transformer is used as the transformer T1. For example, a relay is used for the switches SW1 and SW2.

  The oscillation circuit 1 is a circuit that generates an AC voltage when a DC voltage (VCC) is applied. This AC voltage is, for example, a high-frequency sinusoidal waveform voltage.

  The control circuit 2 is connected to the oscillation circuit 1 and controls the cycle and voltage of the alternating voltage generated in the oscillation circuit 1. Further, the control circuit 2 is connected to the switches SW1 and SW2 and the electrostatic sensor 4, and controls ON / OFF of these switches SW1 and SW2 according to the charged state of the object sensed by the electrostatic sensor 4.

  In the transformer T1, the AC voltage generated in the oscillation circuit 1 is applied between the input terminals on the primary side, and a high voltage is generated on the secondary side. One end of a capacitor C1 is connected to one output terminal on the secondary side of the transformer T1. The other end of the capacitor C1 is connected in parallel with the anode terminal of the forward diode D1 and the cathode terminal of the diode D2 in the reverse direction. One terminal of the switch SW1 is connected to the cathode terminal of the forward diode D1. One terminal of the switch SW2 is connected to the anode terminal of the diode D2 in the reverse direction. The other terminals of these switches SW1 and SW2 are connected to the ground potential. The other output terminal on the secondary side of the transformer T1 is connected to the ground potential.

  On the secondary side of the transformer T1, the discharge electrode 3 is connected to the other end of the capacitor C1, the anode terminal of the forward diode D1, and the cathode terminal of the diode D2 in the reverse direction. The discharge electrode 3 is configured to generate positive and negative ions with respect to the object by applying, for example, a high-frequency AC voltage.

  The electrostatic sensor 4 is a sensor that senses a charged state of an object due to static electricity, and is disposed in the vicinity of the object. Examples of objects include semiconductors such as the electronics industry, electronic devices, liquid crystals, wafers, disks, and the like.

  Next, the operation of the ion generator of the present embodiment will be described with reference to FIG. FIGS. 2A to 2C are waveform diagrams showing the alternating voltage applied to the discharge electrode of the ion generator of the present embodiment (the horizontal axis is time, and the vertical axis is voltage).

  The AC voltage applied to the discharge electrode 3 of the ion generator is (1) normal state, (2) when the electrostatic sensor 4 senses a positively charged object, and (3) the electrostatic sensor 4 is negatively charged. When the detected object is detected, it is controlled according to each.

(1) Normal State In the normal state, the switch SW1 and the switch SW2 are turned off (open state) by the control of the control circuit 2 (specifically, the state where the positive polarity and the negative polarity control are not performed). A sinusoidal AC voltage waveform as shown in a) is applied to the discharge electrode 3. The AC voltage waveform of the sine wave is an AC waveform that is uniform on the positive electrode side and the negative electrode side with reference to 0V. Thereby, in the normal state, positive and negative balanced ions can be generated.

(2) When the electrostatic sensor 4 senses a positively charged object When the electrostatic sensor 4 senses a positively charged object, the switch SW1 is turned on (closed) by the control of the control circuit 2 Then, the switch SW2 is turned OFF (open state), and a current is passed to the ground potential side during the half cycle of the positive electrode to generate an alternating voltage waveform shifted to the negative electrode side as shown in FIG. By applying an alternating voltage waveform shifted to the negative electrode side to the discharge electrode 3, negative ions can be generated.

(3) When the electrostatic sensor 4 senses a negatively charged object When the electrostatic sensor 4 senses a negatively charged object, the switch SW2 is turned on (closed) by the control of the control circuit 2 Then, the switch SW1 is turned OFF (open state), and a current is supplied from the ground potential side during the half cycle of the negative electrode to generate an alternating voltage waveform shifted to the positive electrode side as shown in FIG. By applying the alternating voltage waveform shifted to the positive electrode side to the discharge electrode 3, positive ions can be generated.

  Therefore, according to the ion generator of the present embodiment, the voltage applied to the discharge electrode 3 is controlled by manipulating the opening / closing time of the switches SW1 and SW2 provided on the secondary side of the transformer T1, and the positive / negative ion balance is controlled. Can be controlled. Further, in the case of (2) and (3) above, since the electrostatic sensor 4 senses the charged state of the object whose static electricity is being removed and operates the open / close time, excessive positive ions and negative ions are applied to the object. The charge is not reversed and the charge is not reversed. When the charge removal is completed, the normal state (1) is restored.

  As a result, by controlling the positive / negative ion balance, it is possible to arbitrarily manipulate a state where there are a lot of positive ions or a state where there are a lot of negative ions, and charge the object more effectively than before. It can be neutralized.

  Moreover, since the positive electrode and the negative electrode are applied to the same electrode in the discharge electrode 3, there is no unevenness of positive / negative ion balance due to the distance from the object even in a normal state where the positive and negative electrodes are not controlled. Excellent ion balance can be ensured.

(Embodiment 2)
The ion generator of Embodiment 2 of this invention is demonstrated using FIG. FIG. 3 is a circuit diagram showing the configuration of the ion generator of the present embodiment. Since the waveform diagram showing the AC voltage applied to the discharge electrode of the ion generator of the present embodiment is the same as that of FIG. 2 of the first embodiment, description thereof is omitted here.

  The ion generator of the present embodiment is different from that of the first embodiment in that different types of transformers are used. That is, the ion generator according to the present embodiment includes the oscillation circuit 1, the control circuit 2, the transformer T1a, the capacitor C1, the diodes D1 and D2, the switches SW1 and SW2, the discharge electrode 3, the electrostatic sensor 4, and the like, and the transformer T1a For this, a piezoelectric transformer is used.

  This piezoelectric transformer is a transformer that converts electric energy applied to the primary side into elastic energy by the inverse piezoelectric effect of the piezoelectric ceramic, and further converts this elastic energy into electric energy again by the piezoelectric effect on the secondary side. This piezoelectric transformer is used for miniaturization and high frequency response.

  Even in the operation of the ion generator of the present embodiment configured as described above, (1) ions in a positive and negative balance are generated in a normal state, and (2) the electrostatic sensor 4 is positively charged. Negative ions can be generated when an object is sensed, and (3) positive ions can be generated when the electrostatic sensor 4 senses a negatively charged object.

  Therefore, according to the ion generator of the present embodiment, the same effects as those of the first embodiment can be obtained, and a piezoelectric transformer can be used for the transformer T1a, thereby enabling miniaturization and high frequency response.

(Embodiment 3)
The ion generator of Embodiment 3 of this invention is demonstrated using FIG. FIG. 4 is a circuit diagram showing the configuration of the ion generator of the present embodiment. Since the waveform diagram showing the AC voltage applied to the discharge electrode of the ion generator of the present embodiment is the same as that of FIG. 2 of the first embodiment, description thereof is omitted here.

  The ion generator according to the present embodiment is different from the second embodiment in that different types of switches are used. That is, the ion generator of the present embodiment includes an oscillation circuit 1, a control circuit 2, a transformer T1a, a capacitor C1, diodes D1 and D2, switches SW1a (SW1a-1, SW1a-2), SW2a (SW2a-1, SW2a). -2), the discharge electrode 3, the electrostatic sensor 4, and the like, and a semiconductor relay is used for the switches SW1a and SW2a.

  For example, the semiconductor relay includes a power MOSFET including a light emitting element and a photoelectric element. In this semiconductor relay, when a signal current flows through the input terminal, the light emitting element on the input side emits light, and the emitted light is converted into a voltage by the photoelectric element, and the MOSFET is turned on and off by the converted voltage. Relay. Further, in the present embodiment, each of the switches SW1a and SW2a includes a plurality of semiconductor relays composed of power MOSFETs incorporating a light emitting element and a photoelectric element (two examples (SW1a-1 and SW1a-2 in FIG. 4). , SW2a-1, SW2a-2)) are connected in series. As a result, the high voltage on the secondary side can be divided according to the number of semiconductor relays, and miniaturization and high frequency response are possible.

  Even in the operation of the ion generator of the present embodiment configured as described above, (1) ions in a positive and negative balance are generated in a normal state, and (2) the electrostatic sensor 4 is positively charged. Negative ions can be generated when an object is sensed, and (3) positive ions can be generated when the electrostatic sensor 4 senses a negatively charged object.

  Therefore, according to the ion generator of the present embodiment, the same effects as those of the first and second embodiments can be obtained, and a plurality of semiconductor relays connected in series to the switches SW1a and SW2a can be used. The secondary side high voltage can be divided, and further miniaturization and high frequency response are possible.

  In the example of the ion generator of this embodiment, a plurality of diodes can be connected in series in addition to the semiconductor relay.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  The ion generator of the present invention is used in static eliminators that remove static electricity generated by an object by frictional charging, peeling charging, induction charging, etc., and in particular, in the electronics industry, electrostatic breakdown of semiconductors and electronic devices, liquid crystals -It can be used to prevent device failure due to floating dust such as wafers and disks.

It is a circuit diagram which shows the structure of the ion generator of Embodiment 1 of this invention. (A)-(c) is a wave form diagram which shows the alternating voltage applied to the discharge electrode of the ion generator of Embodiment 1 of this invention. It is a circuit diagram which shows the structure of the ion generator of Embodiment 2 of this invention. It is a circuit diagram which shows the structure of the ion generator of Embodiment 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Oscillation circuit 2 Control circuit 3 Discharge electrode 4 Electrostatic sensor T1, T1a Transformer C1 Capacitor D1, D2 Diode SW1, SW1a, SW2, SW2a Switch

Claims (7)

A transformer to which an AC voltage is applied to the primary side;
A discharge electrode connected by capacitive coupling to the secondary side of the transformer;
A first switch connected in series with a forward diode connected in parallel with the secondary side of the transformer and the capacitive coupling portion; and a second switch connected in series with a reverse diode;
A control circuit that is connected to the first switch and the second switch and controls opening and closing of the first switch and the second switch in order to control positive and negative ion balance;
The first and second switches are opened and closed to generate an alternating voltage waveform shifted to the positive electrode side or the negative electrode side, and the alternating voltage waveform shifted to the positive electrode side or the negative electrode side is applied to the discharge electrode to generate positive ions or An ion generator characterized by generating negative ions. The ion generator according to claim 1,
The ion generator further comprises an electrostatic sensor that senses a charged state of the object. The ion generator according to claim 1 or 2,
The ion generator is characterized in that the transformer is a step-up transformer. The ion generator according to claim 1 or 2,
The ion generator is characterized in that the transformer is a piezoelectric transformer. In the ion generator of any one of Claims 1-4,
Each of said 1st switch and said 2nd switch consists of relays, The ion generator characterized by the above-mentioned. In the ion generator of any one of Claims 1-4,
Each of said 1st switch and said 2nd switch consists of semiconductor relays, The ion generator characterized by the above-mentioned. In the ion generator of any one of Claims 1-4,
Each of the first switch and the second switch is composed of a semiconductor relay in which a plurality are connected in series,
The semiconductor relay is an ion generator comprising a power MOSFET incorporating a light emitting element and a photoelectric element.

Images