JP2909893B2 - AC / DC neutralizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a static eliminator for obtaining a high voltage for static elimination by using an oscillating circuit for increasing the boosting efficiency and boosting the AC voltage with a boosting transformer. The present invention relates to an AC / DC static eliminator capable of performing high-efficiency static elimination with such positive and negative high voltages.

[0002]

2. Description of the Related Art Applicants have disclosed Japanese Utility Model Publication No. 7-4797, Japanese Patent Application Laid-Open No. 5-299191, and Japanese Patent Application Laid-Open No. 6-325892.
A direct current static eliminator as described in Japanese Unexamined Patent Application Publication No. H10-163, etc. has already been provided. This conventional DC static eliminator includes a high-frequency step-up transformer, a high-frequency oscillation circuit connected to the primary side of the high-frequency step-up transformer and self-excited by a DC power supply, and a secondary side and a positive-side neutralizing electrode of the high-frequency step-up transformer. A positive side voltage doubler rectifier circuit connected between the secondary side of the high frequency boosting transformer and a negative side voltage doubler rectifier circuit connected between the negative side neutralizing electrode; The AC voltage is amplified and rectified in a plurality of stages by positive and negative voltage doubler rectifier circuits, so that positive and negative DC voltages are applied to the positive and negative charge eliminating electrodes as complete DC high voltages. Further, between the positive and negative voltage doubler rectifier circuits, the number of stages on the negative side is made smaller than the number of stages on the positive side to balance the generation of positive and negative ions.

Further, a conventional general AC type static eliminator applies alternating high and negative AC high voltages on the secondary side of a step-up transformer to a positive / negative common static elimination electrode.

[0004]

However, in the above-described conventional DC static eliminator, the AC voltage on the secondary side of the step-up transformer is
Since it is a literal DC eliminator that is applied to the positive and negative static elimination electrodes with positive and negative full DC high voltage and negative high voltage respectively, when the static elimination electrode is brought close to the static elimination target, the static elimination target is charged reversely, Unless the interval between the positive and negative charge eliminating electrodes is widened, there is a problem that the positive and negative electrodes interfere with each other.

On the other hand, an AC static eliminator is different from a DC static eliminator.
The voltage on the secondary side of the step-up transformer must be considerably increased, and the step-up transformer becomes large, and the ions from the charge eliminating electrode cannot be transported far away.

An object of the present invention is to provide a positive and negative static elimination electrode,
By being able to apply a high voltage that includes a DC component in both the positive and negative AC, the disadvantages of the conventional DC static eliminator and the disadvantages of the AC static eliminator are both solved, and both advantages are utilized to improve the static elimination efficiency. An object of the present invention is to provide an AC / DC static eliminator that can be designed and has a very simple structure and can be reduced in size and cost.

[0007]

Referring to the example of FIG. 1, an AC / DC static eliminator according to the present invention has a secondary coil 16 provided on the secondary side of a step-up transformer 5 for boosting an AC voltage of an oscillation circuit 4. One of the two output terminals 17 and 18 is grounded, and the other output terminal 18 is connected to the positive electrode 7 via the first capacitor C1 and to the negative electrode via the second capacitor C2. The two output terminals 17 and 18 of the secondary coil 16 are connected to the static elimination electrode 8, and the first diode D <b> 1 is connected to the first diode D <b> 1 in the forward direction from one output terminal 17 to the other output terminal 18. First capacitor C1
And the other output terminal 1
From 8 to one output terminal 17, a second capacitor C2 and a second diode D2 oriented in the forward direction are connected in series. When a positive component AC voltage is generated in the secondary coil, a positive voltage obtained by adding the charging voltage of the first capacitor C1 to the positive component voltage is applied to the positive side static elimination electrode 7, and 2 capacitor C
2 is charged through the second diode D2, and when an AC voltage of a negative component is generated in the secondary coil, a negative voltage obtained by adding the charging voltage of the second capacitor C2 to the voltage of the negative component is a negative-side charge elimination. The voltage is applied to the electrode 8, and the first capacitor C1 is charged through the first diode D1.

Therefore, the secondary coil 1 of the step-up transformer 5
6 has a sine waveform as shown in FIG. 2, a high voltage having a waveform as shown in FIG. 3A is applied to the positive static electricity removing electrode 7, and a negative voltage to the negative static electricity removing electrode 8. A high voltage having a waveform as shown in FIG.

[0009]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 1, the AC / DC static eliminator according to one embodiment of the present invention is roughly divided into a power supply section a and an electrode section b.
The power supply section a and the electrode section b are connected by a cable c for use. The power supply unit a includes a rectifier 1 that rectifies a commercial AC power supply,
A smoothing capacitor 2 for smoothing the output, a constant voltage circuit 3 for stabilizing the discharge of the static elimination electrode, an oscillation circuit 4,
The electrode section b converts (amplifies) the AC voltage on the secondary side of the step-up transformer 5 into a positive high voltage and a negative high voltage that include a DC component in the AC, both positive and negative. It comprises an AC / DC voltage conversion circuit 6 and a positive-side neutralizing electrode 7 and a negative-side neutralizing electrode 8 to which the converted positive high voltage and negative high voltage are respectively applied.

The oscillating circuit 4 includes transistors 9 and 10, resistors 11 and 12, a capacitor 13, a primary coil 15 of the step-up transformer 5, and the like, and oscillates by a constant DC voltage of the constant voltage circuit 3. When this oscillates, an AC high voltage (for example, 2.5 KV) having a sine waveform as shown in FIG. 2 is obtained on the secondary side of the step-up transformer 5.

The AC / DC voltage conversion circuit 6 is an essential part of the present invention. The circuit configuration of the step-up transformer 5 viewed from the secondary coil 16 will be described. One output terminal 17 of the secondary coil 16 is grounded. ing. The other output terminal 18 of the secondary coil 16 is connected to the positive electrode 7 via a first capacitor C1 and a second capacitor C2.
Is connected to the negative side static elimination electrode 8. In addition, both output terminals 17 and 18 of the secondary coil 16 are connected in a forward direction from one output terminal 17 to the other output terminal 18 by a first diode D1 and a first capacitor C1. Are connected in series, and from the other output terminal 18 to the one output terminal 17, a second capacitor C2 and a second diode D2 which is oriented in the forward direction are connected in series. You. In the electrode part b, the connection midpoint between the first capacitor C1 and the first diode D1 is on the positive side static elimination electrode 7, and the connection midpoint between the second capacitor C2 and the second diode D2 is on the positive side. Each is connected to the side static elimination electrode 8. The connection midpoint between the first diode D1 and the second diode D2 is connected to ground via the negative output terminal B.

With such a circuit configuration, as shown in FIG. 3, in the negative half cycle of the AC voltage in which the output terminal 18 is negative with respect to the output terminal 17, the first capacitor C1 is connected to the first capacitor C1.
Of the AC input voltage through the diode D1 of
Charged up. Next, in the positive half cycle in which the output terminal 18 becomes positive with respect to the output terminal 17, this time, the sum of the charging voltage Em of the first capacitor C1 and the AC input voltage Em, that is, 2E
m, and the positive voltage is applied to the positive-side neutralizing electrode 7. Then, such an operation is alternately repeated.

In the positive half cycle in which the output terminal 18 becomes positive with respect to the output terminal 17, the second capacitor C2 is charged to the maximum value Em of the AC input voltage through the second diode D2. Next, in the negative half cycle in which the output terminal 18 becomes negative with respect to the output terminal 17, this time, the sum of the charging voltage Em of the second capacitor C2 and the AC input voltage Em, that is, 2Em
, And this negative voltage is applied to the negative-side discharging electrode 8. Then, such an operation is alternately repeated.

In other words, the AC / DC conversion circuit 6 stores charges in the capacitors C1 and C2 by the rectification of the diodes D1 and D2 when the output terminals 17 and 18 fall to a low potential in both positive and negative cases. , Output terminals 17 and 18
When the voltage rises to a high potential, the charge is carried to the neutralization electrodes 7 and 8 to form a double voltage output waveform.

Therefore, only the positive voltage of the sine waveform obtained by doubling the sine waveform of the AC voltage of the secondary coil 16 to the positive side is applied to the positive-side neutralizing electrode 7 at the same time as the negative-side neutralizing electrode 7 is applied. 8, only the negative voltage of the sine waveform obtained by doubling the sine waveform of the AC voltage of the secondary coil 16 to the negative side is applied, and these positive and negative sine waveforms are out of phase by a half cycle. It can be regarded as an exchange involving minutes.

[0017]

According to the present invention, positive and negative high voltages having waveforms including a DC component in an alternating current are applied to both the positive and negative charge eliminating electrodes, and the positive and negative waveforms are out of phase. Can be transported. In the case of a general DC static eliminator, there is a possibility that the static elimination electrode may be charged when the static elimination electrode is brought close to the object to be neutralized. Even if it is made to be charged, it is not charged. In the case of a conventional DC static eliminator, if the interval between the positive and negative static elimination electrodes is not widened, the positive and negative interfere, so the interval was limited. It can be downsized. Since the circuit for amplifying the secondary side output of the step-up transformer almost twice has a very simple circuit configuration, it can be reduced in size and cost as compared with a conventional DC static eliminator using a multi-stage voltage doubler rectifier circuit. By setting the oscillating frequency of the oscillating circuit, it is possible to handle from a commercial frequency to a high frequency. By providing a circuit on the electrode side for amplifying the secondary side output of the step-up transformer almost twice, it is possible to transmit power from the secondary coil of the step-up transformer to the electrode side by approximately 1 /
Only two voltages are required, which improves safety and reduces failures.

[Brief description of the drawings]

FIG. 1 is an electric circuit diagram of an example of an AC / DC neutralizer according to the present invention.

FIG. 2 is an output voltage waveform diagram of a secondary coil of the step-up transformer in FIG.

FIG. 3 is a diagram showing positive and negative high voltage waveforms applied simultaneously to positive and negative charge eliminating electrodes in FIG. 1;

[Explanation of symbols]

 C1 1st capacitor C2 2nd capacitor D1 1st diode D2 2nd diode 5 Step-up transformer 4 Oscillation circuit 6 AC / DC conversion circuit 7 Positive side static elimination electrode 8 Negative side static elimination electrode 16 Secondary side coil 17 ・ 18 Output terminal

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H05F 3/04 H01T 23/00

Claims (2)

(57) [Claims] 1. On a secondary side of a step-up transformer for boosting an AC voltage of an oscillation circuit, one of two output terminals of a secondary coil is grounded, and the other output terminal is connected via a first capacitor C1. And connected to the positive electrode
The first output terminal is connected to the negative-side static elimination electrode via the second capacitor C2, and both output terminals of the secondary coil have a forward direction from one output terminal to the other output terminal. A diode D1 and a first capacitor C1 are connected in series, and a second capacitor C2 and a second diode D2 in a forward direction are connected from the other output terminal to one output terminal. Are connected in series,
When a positive component AC voltage is generated in the secondary coil, a positive voltage obtained by adding the charging voltage of the first capacitor C1 to the positive component voltage is applied to the positive side static elimination electrode, and the second capacitor When C2 is charged through the second diode D2 and a negative component AC voltage is generated in the secondary coil,
A negative voltage obtained by adding the charge voltage of the second capacitor C2 to the voltage of the negative component is applied to the negative electrode, and the first capacitor C1 is charged through the first diode D1. AC / DC static eliminator. 2. The first and second capacitors C1 and C2, the first and second capacitors C1 and C2,
The second diodes D1 and D2 and the positive and negative static elimination electrodes
2. The static electricity eliminator according to claim 1, wherein the static electricity eliminator is provided on an electrode part separated from the step-up transformer.