TWI437786B - High voltage generating circuit and ion generator - Google Patents

Description

High voltage generating circuit and ion generator

The invention relates to an ion generator used on a static eliminator, in particular to a high voltage generated on an ion generator capable of adjusting the amount of positive and negative ions according to the positive and negative ion balance state around the static elimination object and providing the ion wind. A circuit, and an ion generator equipped with such a high voltage generating circuit.

Electrostatic discharge (ESD) is a great hazard to the manufacture and assembly of precision electronic components. With the miniaturization of semiconductor circuits, the amount of static electricity allowed to become smaller and smaller. Even with a very small amount of static electricity, the insulating layer of the semiconductor germanium circuit and oxide is destroyed due to ESD (electrostatic discharge).

Electrostatic charging also exacerbates the adsorption of dust. Therefore, with the high integration of semiconductor circuits, countermeasures against static electricity are indispensable. The common method for eliminating static electricity is the ion neutralization method, which uses a discharge device to generate positive and negative ion winds to the surface of the static elimination object to achieve the purpose of eliminating static electricity. Such a device is called a static eliminator or a neutralizing ion generator (hereinafter referred to as an ionizer).

Most ionizers employ a high voltage applied to the discharge electrode to create a corona discharge at the tip end. In order to achieve the purpose of generating positive and negative ions, such ion generators apply a high voltage to the discharge electrodes in various ways, for example, applying an alternating voltage to the same electrode, applying positive and negative direct current voltages to different electrodes, and alternately applying the same electrode. Add pulsed positive and negative DC voltage and so on.

Regarding an ion generating circuit (that is, a high voltage generating circuit) that applies an alternating voltage to control the amount of positive and negative ions generated, a method of applying an unbalanced positive and negative voltage to a step-up transformer to perform boosting has been conventionally used (refer to Patent Document 1). However, due to the characteristics of the transformer, when the input waveform of the step-up transformer is unbalanced in some way, the output waveform will be offset, so the generation of positive and negative ions cannot be controlled in a wide range.

In addition, there is also a method of applying a DC bias voltage provided by another DC power source at the output end of the step-up transformer to overlap the AC voltage of the output terminal to improve the voltage range of the output terminal (refer to Patent Document 2) ). However, since the range of the DC bias voltage is about 100V to 200V, there is a problem that the adjustment range of the ion balance is too narrow.

In order to solve the above problems, the following methods have also appeared. That is, a positive DC high voltage is applied to a part of the discharge electrodes to cause corona discharge to generate positive ions; and a negative DC high voltage is applied to the other partial discharge electrodes to cause corona discharge to generate negative ions. The advantage of this method is that the DC high voltage is relatively easy to control, so it is easier to control the amount of ion generation. However, since the positive and negative electrodes are separately provided, the number of electrodes is excessive and the wiring is complicated. Moreover, electrodes that have been applied with the same polarity voltage are more susceptible to aging than electrodes that alternately apply positive and negative voltages.

For the above reasons, an ion generating circuit that applies a DC high voltage to the same discharge electrode and controls the amount of positive and negative ion generation has also appeared (refer to Patent Document 3). Fig. 6 is a view showing a conventionally used ion generating circuit (i.e., a high voltage generating circuit). The high voltage generating circuit is powered by a DC power source 41, and The positive polarity high voltage generating circuit 42a and the negative polarity high voltage generating circuit 42b connected to the switches 41a and 41b are connected.

The high voltage generating circuit 40 is composed of transformers 43a, 43b and voltage doubler rectifier circuits 44a, 44b. The output terminals of the high voltage generating circuits 42a and 42b are connected by equivalent resistors R1 and R1, and the connection point 46 of the resistors R1 and R1 is connected to the electrode pins 47.

The control means 48 issues a control signal to control the switching of the switches 41a, 41b to alternately apply a high voltage of positive polarity and negative polarity to the electrode pins 47 to alternately generate positive and negative ions. The magnitude of the voltage applied to the electrode needle 47 and the magnitude of the positive and negative polarity voltages can be controlled by controlling the length of the on and off times of the switches 41a, 41b. The current flows from the resistor R1 to the connection point 46, to the other resistor R1, and to the diode in the negative polarity high voltage generating circuit 42b (applying a forward voltage). As a result, 1/2 of the output voltage (Em+) of the positive polarity high voltage generating circuit 42a is applied to the electrode needle 47. The same result was obtained when the negative polarity high voltage was generated by the negative polarity high voltage generating circuit 42b. In summary, the disadvantage of the prior high voltage generating circuit is that the voltage applied to the electrode needle 47 is only 1/2 of the voltage generated by the high voltage generating circuit.

Patent Document 1 Japan Special Open 1997-213493

Patent Document 2 Japanese Patent Case 2520311

Patent Document 3 Japan Special Open 2000-058290

In order to solve the above problems, an object of the present invention is to provide a high voltage generating circuit which is realized by a simple circuit configuration and which can apply a high voltage to a discharge electrode without loss and high efficiency, and an ion generator having such a high voltage generating circuit. .

The invention described in claim 1 is a high voltage generating circuit for use in an ion generator, the high voltage generating circuit comprising a positive polarity double voltage rectifying circuit and a negative polarity double voltage rectifying circuit, the ion generator system It is a device for generating positive and negative ions by alternately applying a DC high voltage of a positive polarity or a negative polarity between a discharge electrode and a ground electrode to generate a positive and negative ion, and the high voltage generating circuit is characterized in that the positive polarity is A first resistor is provided between the output terminals of the voltage doubler rectifier circuit, and a second resistor is provided between the output terminals of the negative voltage doubler rectifier circuit, and the positive terminal of the first resistor is The discharge electrode is connected, and a negative electrode terminal of the second resistor is connected to a negative electrode end of the first resistor, and a positive electrode terminal of the second resistor is grounded.

Further, the invention according to claim 2 is characterized in that, in the high voltage generating circuit according to the first aspect of the invention, when the voltage doubler rectifier circuit generates a voltage, the other voltage doubler rectifier circuit A circuit equivalent to a circuit in which a unidirectional conductive electronic component to which a reverse voltage is applied is connected in parallel with a resistor provided between an output terminal of the other voltage doubler rectifier circuit is connected.

The invention described in claim 3 is in the high pressure described in the application or The generating circuit is characterized in that the DC voltage applied to the discharge electrode is positive, and the output voltage of the positive electrode double voltage rectifier circuit is between the discharge electrode and the ground electrode. The voltage value proportionally distributed between the resistance value and the second resistance value, and when the polarity is negative, the output voltage of the negative polarity double voltage rectifier circuit is a resistance between the discharge electrode and the ground electrode A voltage value proportional to the value of the first resistance value.

The invention described in claim 4 is characterized in that the voltage doubler rectifier circuit is a Villard circuit or a Cockcroft-Walton circuit.

According to such a high voltage generating circuit configuration, the high voltage generated by the positive polarity or negative polarity high voltage generating circuit can be applied to the discharge electrode without being greatly reduced. For example, when a current limiting resistor of 20 MΩ is provided between the output terminals of the high voltage generating circuit, since the electric resistance between the discharge electrode and the ground electrode at the time of discharge is about 200 MΩ, 90% of the voltage generated by the high voltage generating circuit is applied to the discharge electrode. on.

The invention described in claim 5 is an ion generator including a power supply circuit, a high voltage generating circuit, and a discharge electrode connected to an output end of the high voltage generating circuit, the high voltage generating circuit having There is a positive polarity double-voltage rectifying circuit that generates a high voltage of a positive polarity and a negative polarity double voltage rectifying circuit that generates a high voltage of a negative polarity by a voltage applied by the power supply circuit, and the ion generator refers to a discharge through the discharge. A device that alternately applies a positive or negative DC high voltage between the electrode and the ground electrode to cause a corona discharge to the discharge electrode to generate positive and negative ions. The generator is characterized in that a first resistor is provided between the output terminals of the positive polarity double voltage rectifier circuit, and a second resistor is provided between the output terminals of the negative voltage doubler rectifier circuit. The discharge electrode is connected to the positive electrode end of the first resistor, and the negative terminal of the second resistor is connected to the negative terminal of the first resistor, and the positive terminal of the second resistor is grounded. .

The invention according to claim 5 is characterized in that, in the ion generator according to the fifth aspect of the invention, when the voltage doubler rectifier circuit generates a voltage, the other voltage doubler rectifier circuit is A circuit equivalent to a circuit in which a unidirectional conductive electronic component to which a reverse voltage is applied is connected in parallel with a resistor provided between the output terminals of the other voltage doubler rectifier circuit is connected.

The invention according to claim 7 is characterized in that, in the ion generator according to claim 5 or 6, the direct current voltage applied to the discharge electrode is characterized in that, in the case of a positive polarity, The output voltage of the positive electrode voltage doubler rectifier circuit is proportionally distributed by a resistance value between the discharge electrode and the ground electrode and the second resistance value, and when the polarity is negative, the negative electrode is formed The output voltage of the voltage doubler rectifier circuit is a voltage value proportionally distributed by the resistance value between the discharge electrode and the ground electrode and the first resistance value.

The invention described in claim 8 is characterized in that, in the ion generator according to claim 5 or 6, the voltage doubler rectifier circuit is a Villard circuit or a Cockcroft-Walton circuit.

According to the present invention, with a simple circuit configuration, the positive and negative DC high voltages can be alternately applied to the same discharge electrode without drastically decreasing.

Hereinafter, the best mode for carrying out the invention will be described in detail by way of examples, but the invention is not limited to the following examples.

Example 1

Fig. 1 is a schematic exploded view of an ion generator as an embodiment of the present invention. This ion generator generates a corona discharge by using a plurality of electrodes connected in parallel in the direction perpendicular to the paper surface, and ejects a stream of air containing positive and negative ions to the object to be neutralized. Fig. 1 is a schematic exploded view of the periphery of a central portion of a rectangular ion generator body. This device is constituted by an ion generator body 1, ion sensors 2a and 2b, and a high voltage generating circuit 6 which will be described later. The ionizer body 1 includes a discharge electrode 3, a grid 4 serving as an opposite electrode, and a blower 5 forming an air flow. The grid 4 used as the opposite electrode is grounded.

Figure 2 is a high voltage generating circuit equipped with a voltage doubler rectifier circuit. The voltage doubler rectifier circuit is a four-fold frequency voltage rectifier circuit composed of a double-layer Villard circuit. This high voltage generating circuit is composed of a power source, a power source control circuit 7, and a high voltage generating circuit 6. Among them, the power supply control circuit 7 includes a control switch to alternately apply a high voltage of a positive polarity and a negative polarity, and the power supply control circuit 7 is substantially the same as the foregoing prior art.

The high voltage generating circuit 6 includes a positive polarity high voltage generating circuit 6a and a negative polarity high voltage generating circuit 6b. The positive polarity high voltage generating circuit 6a is composed of a transformer Tra, a positive polarity double voltage rectifying circuit, and a current limiting resistor Ra provided between the output terminals. Similarly, the negative polarity high voltage generating circuit 6b is composed of a transformer Trb, a negative voltage doubler rectifier circuit, and a current limiting resistor Rb provided between the output terminals.

In the high voltage generating circuit 6 shown in FIG. 2, the positive polarity output terminal of the positive polarity voltage doubler rectifier circuit is connected to the discharge electrode 3, and the negative polarity output terminal is connected to the negative polarity output terminal of the negative polarity double voltage rectifier circuit. Further, the positive polarity output terminal of the negative polarity double voltage rectifier circuit is grounded.

The operation of the high voltage generating circuit shown in Fig. 2 will be described below. In the state in which the high voltage is applied to the positive polarity high voltage generating circuit 6a by the power supply control circuit 7 without applying a high voltage to the negative polarity high voltage generating circuit 6b, the voltage generated between the output terminals of the positive polarity double voltage rectifying circuit is a transformer. The voltage Em generated by Tra is 4 times (4Em). As a result, a positive polarity voltage is applied to the discharge electrode 3, and the tip is corona-discharged to generate positive ions, and at this time, a current flows from the discharge electrode 3 to the counter electrode (ground electrode). Since the diodes Db1 to Db4 in the negative polarity double-voltage rectification circuit are applied with a reverse voltage at this time, the connection manner of these diodes and the current limiting resistor Rb can be equivalent to a parallel circuit.

Similarly, in the state where the high voltage is applied to the negative polarity high voltage generating circuit 6b by the power supply control circuit 7, and the high voltage is not applied to the positive polarity high voltage generating circuit 6a, the output terminals of the negative polarity double voltage rectifying circuit 6b are generated. The voltage is 4 times the voltage -Em generated by the transformer Trb ( -4Em). As a result, a negative polarity voltage is applied to the discharge electrode 3, and the tip is corona-discharged to generate negative ions, and at this time, a current flows from the counter electrode (ground electrode) to the discharge electrode 3. Since the diodes Da1 to Da4 in the positive polarity voltage doubler rectifier circuit are applied with a reverse voltage at this time, the connection manner of these diodes and the current limiting resistor Ra can be equivalent to a parallel circuit.

Fig. 3 shows the equivalent circuits of the positive polarity double voltage rectifier circuit and the negative polarity voltage doubler rectifier circuit, respectively. The equivalent circuit when a high voltage is applied to the positive polarity double voltage rectifier circuit is shown in Fig. 3(a); the equivalent circuit when a high voltage is applied to the negative polarity voltage doubler rectifier circuit is shown in Fig. 3(b). Here, if it is assumed that the current limiting resistors Ra and Rb are each 20 MΩ, since the electric resistance between the discharge electrode 3 and the opposite electrode (ground electrode) is 200 MΩ, 90% of the voltage 4Em generated by the voltage doubler rectifier circuit is applied to the discharge electrode 3 on. In addition, the current limiting resistors Ra and Rb can suppress the overcurrent and function as a protection circuit.

Example 2

Fig. 4 is a high voltage generating circuit equipped with a voltage doubler rectifying circuit, wherein the voltage doubler rectifying circuit is a four-fold frequency double voltage rectifying circuit formed by a double-layer Cockcroft-Walton circuit instead of the above-mentioned double-layer Villard circuit. An equivalent circuit when a positive DC high voltage is applied to the discharge electrode 3 by the positive polarity high voltage generating circuit 6c is shown in Fig. 3(a). Similarly, an equivalent circuit when a negative DC high voltage is applied to the discharge electrode 3 by the negative polarity high voltage generating circuit 6d is as shown in Fig. 3(b). Like the voltage doubler rectifier circuit constructed using the Villard circuit, the voltage generated by this voltage doubler rectifier circuit It is applied to the discharge electrode 3 without any drop.

Example 3

Figure 5 is a diagram showing the power supply waveform of the circuit shown in Figure 2. In Fig. 5, the input voltage waveform 1 is a waveform when the power supply control circuit 7 applies a voltage of -10 V to the transformer Trb. The input voltage waveform 2 is a waveform when the power supply control circuit 7 applies a voltage of +10 V to the transformer Tra. Here, the positive and negative reference voltages are ground voltages.

By applying a voltage of +10 V and -10 V to the positive polarity high voltage generating circuit 6a and the negative polarity high voltage generating circuit 6b alternately, it can be confirmed that the following result is applied to the discharge electrode 3 as indicated by the output voltage waveform 3. A high voltage of about 4.5KV. In addition, as can be seen from FIG. 5, when the input voltage waveform 1 and the input voltage waveform 2 are in the OFF state, they are slightly higher than the ground voltage (0 V). And the waveform of the waveform is declining, but since the voltage below 5V does not turn the voltage doubler rectifier circuit ON, it can be equivalent to the ground voltage.

As shown in the output voltage waveform 3 of Fig. 5, positive and negative DC voltages of about 4.5 kV are alternately applied to the discharge electrode 3. In fact, the voltage doubler rectifier circuit 6 generates a voltage of about 5 kV between its output terminals, but as described above, the voltage drop is caused by the current limiting resistor Ra or Rb, and Ra (20 MΩ) or Rb (20 MΩ) is the discharge electrode. 3 and 10% of the resistance (about 200 MΩ) between the ground electrodes, and therefore, the voltage applied to the discharge electrode 3 is ±4.5 KV.

Industry availability

According to the present invention, a simple circuit configuration can be applied to the discharge electrode without causing a large drop in the high voltage generated by the high voltage generating circuit. Further, since it is possible to manufacture an ion generator having such a high voltage generating circuit, it is of industrial value.

1‧‧‧Ion generator body

2a, 2b‧‧‧ ion sensor

3‧‧‧Discharge electrode

4‧‧‧ grid (counter electrode)

5‧‧‧Air blower

6‧‧‧Ion generating circuit (high voltage generating circuit)

7‧‧‧Power control circuit

[Fig. 1] A schematic exploded view of an ion generator of an embodiment of the present invention.

[Fig. 2] A high-voltage generating circuit diagram using a Villard circuit as a voltage doubler rectifier circuit.

[Fig. 3] An equivalent circuit diagram of each of the positive polarity voltage doubler rectifier circuit and the negative polarity voltage doubler rectifier circuit of the high voltage generating circuit in the embodiment of the present invention.

[Fig. 4] A Cockcroft-Walton circuit is used as a high-voltage generating circuit diagram of a voltage doubler rectifier circuit.

[Fig. 5] An input/output voltage waveform diagram of a high voltage generating circuit using a Villard loop as a voltage doubler rectifier circuit in the embodiment of the present invention.

[Fig. 6] A high voltage generating circuit diagram based on the prior art.

3‧‧‧Discharge electrode

6‧‧‧Ion generating circuit (high voltage generating circuit)

7‧‧‧Power control circuit

Claims (6)

A high voltage generating circuit for use in an ion generator, the high voltage generating circuit comprising a positive polarity double voltage rectifying circuit and a negative polarity double voltage rectifying circuit, wherein the ion generator means alternating between a discharge electrode and a ground electrode A device for applying a DC high voltage of a positive polarity or a negative polarity to generate a corona discharge on a discharge electrode to generate positive and negative ions, the high voltage generation circuit characterized in that: between the output terminals of the positive polarity double voltage rectifier circuit a first resistor is provided, and a second resistor is provided between the output terminals of the negative voltage doubler rectifier circuit, and the discharge electrode is connected to the positive electrode of the first resistor, and the first resistor is connected to the first resistor. The negative terminal of the second resistor is connected to the negative terminal, and the positive terminal of the second resistor is grounded. The voltage doubler rectifier circuit is a Villard circuit or a Cockcroft-Walton circuit. The high voltage generating circuit according to claim 1, wherein when one of the voltage doubler rectifier circuits generates a voltage, the other voltage doubler rectifier circuit is unidirectionally conductive with a reverse voltage to be applied. The circuit in which the electronic component and the resistor provided between the output terminals of the other voltage doubler rectifier circuit are connected in parallel is equivalently priced. The high voltage generating circuit according to the first or second aspect of the invention, wherein the DC voltage applied to the discharge electrode is an output of the positive polarity double voltage rectifying circuit when it is positive. The voltage is a voltage value proportionally distributed between the resistance value between the discharge electrode and the ground electrode and the second resistance value, and when the polarity is negative, the output voltage of the negative polarity double voltage rectifier circuit is borrowed. A voltage value proportionally distributed between the resistance value between the discharge electrode and the ground electrode and the first resistance value. An ion generator comprising a power supply circuit, a high voltage generating circuit, and a discharge electrode connected to an output end of the high voltage generating circuit, wherein the high voltage generating circuit is provided with a voltage applied by the power circuit a positive polarity double voltage rectifying circuit for generating a positive voltage and a negative voltage doubler rectifying circuit for generating a high voltage of a negative polarity, wherein the ion generator means alternating positive polarity or between the discharge electrode and the ground electrode A device for generating positive and negative ions by causing a negative DC high voltage to generate a corona discharge on a discharge electrode, wherein the ion generator is provided with a first one between the output terminals of the positive polarity double voltage rectifier circuit The resistor is provided with a second resistor between the output terminals of the negative voltage doubler rectifier circuit, and the discharge electrode is connected to the positive terminal of the first resistor, and the negative terminal of the first resistor is connected The negative terminal of the second resistor is connected, the positive terminal of the second resistor is grounded, and the voltage doubler rectifier circuit is a Villard circuit or Cockcroft-Walton circuit. An ion generator as described in claim 4, When the voltage doubler rectifier circuit of one of the above generates a voltage, the other voltage doubler rectifier circuit is a unidirectional conductive electronic component to which a reverse voltage is to be applied, and a voltage doubler rectifier circuit provided on the other side. The resistors between the output terminals are equally priced circuits in parallel. The ion generator according to the fourth or fifth aspect of the invention, wherein the DC voltage applied to the discharge electrode is an output of the positive polarity double voltage rectifier circuit when the positive polarity is present. The voltage is a voltage value proportionally distributed between the resistance value between the discharge electrode and the ground electrode and the second resistance value, and when the polarity is negative, the output voltage of the negative polarity double voltage rectifier circuit is borrowed. A voltage value proportionally distributed between the resistance value between the discharge electrode and the ground electrode and the first resistance value.