JPH10199654A - Negative ion generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a negative ion generator of high safety and low cost comprising a smaller number of parts. SOLUTION: A piezoelectric transformer 25 boosts an AC voltage from an oscillation circuit 23 to be outputted. A circuit comprising diodes 27, 29 and a smoothing capacitor 31 rectifies an AC high voltage from the piezoelectric transformer 25 to the negative side and smoothes it to generate a DC high voltage E1 of a negative potential to be outputted. A current limiting resistance 35 is provided between a capacitor 31 and a discharge electrode 3 as a measure for safety for preventing instantaneous discharge of accumulated charge in the smoothing capacitor 31 by contact of a finger tip or the like with the discharge electrode 33 during negative ion generation by corona discharge from the discharge electrode 33. By the DC high voltage E1 of the negative potential applied from the side of the diodes 27, 29 and the smoothing capacitor 31 through the current limiting resistance 35 to the discharge electrode 33, corona discharge is generated close to the discharge electrode 33, thereby negative ions are generated by this corona discharge to be emitted to air.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative ion generator for generating negative ions from air by corona discharge.

[0002]

2. Description of the Related Art Conventionally, a negative ion generator as shown in FIG. In this device, an applied AC voltage is boosted by a winding transformer 1 to generate an AC high voltage, which is rectified to a negative side by diodes 5 and 7 through a DC blocking capacitor 3 and smoothed by a capacitor 9. As shown in FIG. 1B, a negative DC high voltage E1 is generated. Then, by applying this to the discharge electrode 13 through the current limiting resistor 11, corona discharge occurs near the discharge electrode 13, thereby generating negative ions.

[0003]

By the way, in the above-mentioned negative ion generator, the above-mentioned winding transformer 1, capacitor 3, diodes 5, 7 and capacitor 9 reduce the DC potential of the negative potential from the AC voltage supplied from the input power supply. Voltage E1
Is generated in the high voltage generating circuit. Moreover, even if a part of the human body such as a fingertip accidentally contacts the discharge electrode 13 during the generation of negative ions, the electric charges stored in the capacitors 3 and 9 are not instantaneously discharged. As a safety measure, a current limiting resistor 11 is interposed between the capacitor 9 and the discharge electrode 13.

[0004] As described above, the above-mentioned conventional negative ion generator comprises a high voltage generating circuit using the winding transformer 1 which has a certain restriction on miniaturization. In addition to transformer 1, DC blocking capacitor 3
In addition, a large number of circuit elements such as diodes 5, 7 and a smoothing capacitor 9 are required. For this reason, in the above-described conventional negative ion generator, it has not been possible to reduce the cost by reducing the number of components and reducing the size of the device while ensuring sufficient safety.

Accordingly, it is an object of the present invention to provide a low-cost negative ion generator with high safety and a small number of parts.

[0006]

A negative ion generator according to the present invention generates negative ions by corona discharge from a discharge electrode, and is used as a high voltage power supply for applying a high negative voltage to the discharge electrode. It has a piezoelectric transformer.

According to the above configuration, the piezoelectric transformer is provided as a high-voltage power supply for applying a high negative voltage to the discharge electrode. As described above, there is no problem that the size of the device is increased due to the winding transformer. Further, since there is no need to provide a DC blocking capacitor for blocking DC current from the winding transformer, the number of components can be reduced.

According to a preferred embodiment of the present invention, it is possible to further comprise a DC high voltage generating means for inputting an AC high voltage from the piezoelectric transformer and generating a negative DC high voltage.

[0009] Also in this configuration, since the piezoelectric transformer is used as the high-voltage power supply, the same effects as described above can be obtained.

[0010] In another embodiment different from the above, a pulsating high voltage generating means for generating a negative pulsating high voltage by inputting an AC high voltage from a piezoelectric transformer may be further provided.

According to this configuration, a rectifying circuit for rectifying the AC high voltage from the piezoelectric transformer and a smoothing capacitor for smoothing the output voltage from the rectifying circuit are not required. Furthermore, since a current limiting resistor for limiting the instantaneous discharge of the electric charge stored in the smoothing capacitor is not required, the number of components can be significantly reduced.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 2A is a block diagram showing the overall configuration of the negative ion generator according to one embodiment of the present invention.

The above-mentioned device includes a high voltage generating circuit 21 and a discharge electrode 33 as shown in the figure.

The discharge electrode 33 is for generating negative ions by generating a corona discharge, and is connected to the high voltage generation circuit 21. As the discharge electrode 33, for example, a needle electrode, a linear electrode, a blade-shaped electrode, or the like is used.

The high voltage generating circuit 21 is for generating a negative DC high voltage with a DC voltage applied from, for example, a DC power supply (not shown) and applying it to the discharge electrode 33. It includes a piezoelectric transformer 25, diodes 27 and 29, a smoothing capacitor 31, and a current limiting resistor 35.

The oscillation circuit 23 is driven by a DC voltage applied from the DC power supply (not shown) as a drive source, and oscillates at a predetermined amplitude and a predetermined frequency. The piezoelectric transformer 25 is
The AC voltage output from the oscillation circuit 23 is boosted and output. The circuit composed of the diodes 27 and 29 and the smoothing capacitor 31 rectifies and smoothes the AC high voltage from the piezoelectric transformer 25 to the negative side and smoothes it as shown in FIG. Is generated and output.

During the generation of negative ions due to corona discharge from the discharge electrode 33, the current limiting resistor 35 reduces the accumulated charge in the smoothing capacitor 31 due to the contact of a part of the human body such as a fingertip with the discharge electrode 33. As a safety measure to prevent instantaneous discharge, a safety measure is provided between the capacitor 31 and the discharge electrode 33. The negative DC high voltage E1 applied to the discharge electrode 33 from the diodes 27 and 29 and the smoothing capacitor 31 side through the current limiting resistor 35,
Corona discharge occurs near the discharge electrode 33, and negative ions are generated by the corona discharge and released into the air.

In the above configuration, since the piezoelectric transformer 25 has an output capacitance (= corresponding to the capacitor 3 shown in FIG. 1), it is not necessary to connect the capacitor to the output side of the piezoelectric transformer 25. Points can be reduced. Further, unlike the winding transformer 1 as shown in FIG. 1, the piezoelectric transformer 25 has a small volume, so that the entire device can be reduced in size.

FIG. 3A is a block diagram showing the overall configuration of a negative ion generator according to another embodiment of the present invention.

The negative ion generator according to the present embodiment has an oscillation circuit 23 instead of the winding transformer 1 as shown in FIG.
This is the same as the above-described embodiment in that the high voltage generating circuit 22 is configured using the piezoelectric transformer 25 and the piezoelectric transformer 25. However, in order to obtain a negative pulsating high voltage E2 as shown in FIG. Is a feature of the negative ion generator according to the present embodiment. Therefore, in this embodiment,
The high voltage generating circuit 21 is not provided with the smoothing capacitor 31 and the current limiting resistor 35 as shown in FIG.

In the above configuration, even if the current limiting resistor 35 is not provided, there is no problem in safety. The reason is that the smoothing capacitor 31 as shown in FIG. 2 is not provided, so that even if a part of the human body such as a finger contacts the discharge electrode 33,
This is because the charge stored in the capacitor 31 is not instantaneously discharged. Further, unlike the winding transformer 1 as shown in FIG. 1, the piezoelectric transformer 25 has an extremely small current capacity and an extremely large output impedance, so that a part of a human body such as a finger contacts the discharge electrode 33 temporarily. In this case, since the step-up ratio is reduced, there is no possibility that a large amount of discharge is instantaneously generated due to the contact with the discharge electrode 33.

Actually, when the present inventors brought a finger close to the tip of the discharge electrode 33 of the apparatus of FIG. 3 to about 1 mm, blue discharge light could be confirmed between the tip of the discharge electrode 33 and the fingertip. The impact felt on the finger at that time was insignificant, and no impact was felt when the finger was brought closer to the discharge electrode 33 and completely contacted.

Further, as a result of a mutual comparison of the amount of negative ions generated by using the apparatus according to the present embodiment and the conventional apparatus shown in FIG.
While a negative ion generation amount of 0 (pieces / cc) was obtained,
From the device according to the present embodiment, 68, 30 which are substantially the same
A negative ion generation amount of 0 (pieces / cc) was obtained. Therefore,
As shown in FIGS. 1 and 2, a negative high DC voltage is applied to the discharge electrode 13 (33), and a negative pulsating high voltage E 2 is applied to the discharge electrode 33 as in the present embodiment. There is no practical problem.

According to the above configuration, not only the DC blocking capacitor 3 as shown in FIG. 1 but also the smoothing capacitor 31 and the diode 29 can be reduced, and the safety problem does not occur at all. Since the current limiting resistor 35 can also be reduced, the number of components can be significantly reduced and the size can be reduced without any problem in terms of safety.

In the apparatus shown in FIG. 3, the current limiting resistor 35 may be connected for further safety.

The above-mentioned contents relate to one embodiment of the present invention, and do not mean that the present invention is limited to only the above-mentioned contents.

[0028]

As described above, according to the present invention,
It is possible to provide a low-cost negative ion generator with high safety and a small number of parts.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a negative ion generator according to a conventional technique.

FIG. 2 is an explanatory diagram of a negative ion generator according to one embodiment of the present invention.

FIG. 3 is an explanatory diagram of a negative ion generator according to another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 21 High voltage generation circuit 23 Oscillation circuit 25 Piezoelectric transformer 27, 29 Diode 31 Capacitor 33 Discharge electrode 35 Current limiting resistor

Claims (3)

[Claims] 1. A negative ion generator for generating negative ions by corona discharge from a discharge electrode, comprising a piezoelectric transformer as a high voltage power supply for applying a high negative voltage to the discharge electrode. Negative ion generator. 2. The negative ion generator according to claim 1, further comprising a DC high voltage generating means for inputting an AC high voltage from said piezoelectric transformer to generate a DC high voltage of a negative potential. Negative ion generator. 3. The negative ion generator according to claim 1, further comprising a pulsating high voltage generating means for inputting an alternating high voltage from the piezoelectric transformer to generate a negative pulsating high voltage. Negative ion generator.