JPH0455304A - Ozone generating circuit - Google Patents

Abstract

PURPOSE:To drive a piezoelectric element even with the frequency exceeding the audible frequency without the need of an expensive special drive circuit by taking out a tap voltage from the winding of a driving transformer to impress to the piezoelectric element. CONSTITUTION:The DC voltage of a DC power source 4 is self-oscillated includ ing the transformer 3 according to the ON/OFF of a transistor 6 operated by the signal from an oscillating source 5, and the voltage V1 boosted by the ratio Ns/Np1 of the boosting transformer 3 is impressed to a creeping discharge body 1, and the creeping discharge is carried out on the creeping discharge body 1 so that the air is brought into reaction to generate ozone. The piezoelec tric element 2 is oscillated with the voltage V2 generated by the winding Np1 and the winding Np2 increasingly wound to the winding Np1. In this circuit, when the voltage of power source 4 is DC12V, the discharge voltage V1 is 2800V, and the frequency of the oscillating source 5 is 19.5KHz, the voltage V2 of the piezoelectric element 2 is 50Vp-p (sine wave), and the target oscillating effect is obtained by this method.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to an ozone generation circuit that applies a high voltage to a creeping discharge body to generate ozone.

(b) Conventional technology In an ozone generator, a high voltage generated by boosting an AC signal from a self-help oscillator using a step-up transformer is applied to a creeping discharge body with a dielectric layer made of fine ceramic, and air is generated by the discharge of the creeping discharge body. There are some products that react to produce ozone. This type of ozone generator is equipped with a piezoelectric element in order to prevent deposits (dirt) on the discharge body for ozone generation, improve nitrate mist, etc., and solve problems during discharge. A separate power source for driving is provided to drive the piezoelectric element (Japanese Patent Laid-Open No. 62-201638, 63-
No. 190702).

(c) Problems to be Solved by the Invention In the above-mentioned creeping discharge body equipped with a piezoelectric element, the resonance frequency of the piezoelectric element vibrates most efficiently when driven at about 2 KHz to 8 KHz, but since it is in the audible range, There was a problem in that it could be harsh on the ears and its use was restricted. or,
If the resonance point shifts even slightly, the vibration range becomes extremely small, which poses the problem of requiring individual adjustments in terms of product management. On the other hand, resonance frequencies beyond the audible range (1
Vibration at frequencies above 8KHz requires high voltage;
If this were to be achieved using an independent drive circuit, there would be a problem in that the entire device would be expensive.

The invention of claim 1 has been made focusing on the above-mentioned problem, and is capable of driving a piezoelectric element at a frequency exceeding an audible frequency, and without requiring an expensive special driving circuit. The purpose of the present invention is to provide an ozone generation circuit that can generate ozone.

In addition, ozone generators are used in divine environments, and are most susceptible to changes in humidity and temperature in the air, which is the raw material (oxygen). There is a ~5-fold change in development. However, conventional ozone generators do not have adjustment means that can generate ozone stably even with changes in humidity, etc., so it is not always possible to obtain the required amount of ozone for use. There was a problem that the equipment could not be obtained.

The invention of claim 2 has been made with attention to the above problem, and provides an ozone generation circuit that can maintain a constant amount of discharge even when changes in humidity and temperature occur, and can secure a stable required amount of ozone. is intended to provide.

Further, the ozone generator is equipped with a fan to blow air in order to uniformly output a predetermined amount of generated ozone. However, if this fan stops while generating ozone due to a malfunction or other reason, ozone will not be output properly, causing ozone to vary in density depending on the area, resulting in high concentration of ozone floating around the equipment, which can cause health problems. It may remain inside the device and have a negative impact on circuit elements. In addition, even if the fan is rotating, there is a risk of excessive current flowing due to an abnormality in the discharge of the creeping discharge element, resulting in a fire.Also, since high voltage is used, if the abnormality in discharge is left unattended, there is a risk of damage to the equipment. . Furthermore, if only the fan is rotating even though ozone is not being generated normally,
The appearance may give the impression that the device is operating normally. However, conventional ozone generators are not equipped with any means to deal with abnormalities, and have problems with reliability and safety.

Invention 4 of Claim 3 has been made with attention to the above problem, and the object is to provide a highly reliable ozone generation circuit that detects abnormality when it occurs and operates safely. It is said that

(d) Means and operation for solving the problem The ozone generating circuit of the invention of claim 1 generates ozone by applying a voltage boosted by a drive transformer to a creeping discharge body, and also applies a voltage boosted by a drive transformer to a creeping discharge body. In a device equipped with a piezoelectric element for removing kimono, dirt, etc., a tap voltage is extracted from the winding of the drive i-lance and applied to the piezoelectric element.

In this ozone generation circuit, the tap voltage is extracted from the winding of the drive transformer and applied to the piezoelectric element, so the voltage to the piezoelectric element can be freely set by changing the tap, and a special circuit is not required. A voltage of a required frequency and level can be applied to the piezoelectric element even if it is not provided separately.

An ozone generation circuit according to a second aspect of the present invention is a circuit that generates ozone by applying a voltage boosted by a drive transformer to a creeping discharge body, and a discharge current detection circuit that detects a discharge current flowing through the creeping discharge body; The discharge current characteristically includes a filter circuit that derives only components in a predetermined frequency range from the discharge current, and a feedback circuit that feeds back the output of this filter circuit to control the discharge current.

In this ozone generation circuit, for example, when the humidity is low, discharge in the air increases and the amount of ozone increases. Therefore, the high frequency air discharge current component, which is different from the discharge current for driving the discharge body, increases proportionally. From the discharge current, only the frequency component corresponding to the h'l electric component in the air is derived by the filter circuit, and its output is fed back to the feedback circuit, which acts to reduce the driving discharge current, and the discharge current remains constant. It is controlled so that

In the ozone circuit according to the third aspect of the invention, a voltage boosted by a drive transformer is applied to a creeping discharge body to discharge it and generate ozone, and in a circuit provided with a fan, a fan stop function is provided to detect the stop of the fan. A detection circuit, and/or a discharge abnormality detection circuit that detects an abnormality in the discharge circuit of the creeping discharge body, and a circuit that interrupts the circuit in response to the fan stop detection and/or the discharge abnormality detection. We are preparing for

In this ozone generation circuit, when the fan stops rotating (including at low speed), this is detected by the fan stop detection circuit. Further, when the discharge current of the creeping discharge body exceeds a predetermined value (abnormal discharge and seat type), it is detected by the discharge abnormality detection circuit. When a fan stoppage is detected or a discharge abnormality is detected, the fan is stopped and the operation of the discharge circuit is stopped. This prevents the operation from continuing in an abnormal state.

(E) Examples The present invention will be explained in more detail with reference to Examples below.

Embodiment of Claim 1> FIG. 1 is a circuit connection diagram of an ozone generation circuit showing an embodiment of the invention of Claim 1. In the figure, reference numeral 1 denotes a creeping discharge body for ozone generation using fine ceramic as a dielectric layer, and a piezoelectric element 2 is attached to prevent deposits (dirt) and the like. The secondary winding N of the step-up transformer 30 is connected to the picture electrode of the surface discharge body 1, one end of the DC power supply 4 is connected to point A of the primary winding of the step-up transformer 3, and the other end of the DC type WA4 is connected to the point A of the primary winding of the step-up transformer 3. It is connected to point B of the step-up transformer 3 via the emitter and collector of the transistor 6. Note that the oscillation source 5 is connected to the base of the transistor 6. Also,
The primary winding of the step-up transformer 3 has a winding F'lpt added to the winding Na, and taps C and A are connected to the piezoelectric element 2.

In this ozone generation circuit, the DC voltage of the DC power supply 4 is turned ON10 by the transistor 6 by the signal from the oscillation source 5.
In response to F F, the transformer 3 is automatically oscillated, and the step-up transformer 3 generates N, /N.

A voltage (2) boosted at a ratio of is applied to the creeping discharge body 1, the creeping discharge body 1 discharges, and at this time, air reacts and ozone is generated. Further, a voltage 2 due to the winding N□ and NPt which is further wound around the winding N□ is applied to the piezoelectric element 2, causing the piezoelectric element 2 to vibrate.

In this circuit, when the voltage of all power sources 4 is DC12V, the discharge voltage V+ = 2800 VP-P, and the frequency of the oscillation source 5 is 19.5 KHz, the voltage of the piezoelectric element 2 V! is 50
The result was a VP-P (sine wave), which produced the desired vibration effect. In the conventional technology, when a piezoelectric element drive circuit is provided separately from the step-up transformer 3, the frequency is 17 KHz and 20 KHz.
This is a significant improvement compared to the previous time when it was only possible to control up to VP-P and the vibration effect was extremely small.

<Embodiment of Claim 2> FIG. 2 is a circuit connection diagram of an ozone generating circuit according to an embodiment of the invention of Claim 2. In the same figure, resistor R4, capacitor C
3, transistor 6, step-up transformer 3 and creeping discharge body 1
A transformer-coupled self-help oscillation circuit is constructed, and a high voltage is applied to the creeping electric body l. The l end of the secondary winding N of the step-up transformer 3 is connected to GN through the resistor R2.
D (ground) connected. This resistor R1 constitutes a discharge current detection circuit 9. Step-up transformer N, and resistor R
One end of the capacitor C1 is connected to the connection point of the capacitor C1, the other end of the capacitor C1 is connected to the base of the transistor 7, and a resistor R7 is connected between the other end of the capacitor C5 and GND.
is connected. A filter 10 is constituted by this capacitor C1 and resistor R1. The transistor 7 is provided to amplify the signal from the filter 10, and has an emitter connected to GND and a collector connected to a +12V power supply via a resistor R3. Further, a rectifying diode D is connected to the collector of the transistor 7, and a parallel circuit of a capacitor C2 and a resistor R2 is connected to the output side of the diode D. connected to the base. Further, the resistor R4 is a variable resistor and is used to adjust the oscillation intensity.

In this embodiment circuit, the waveform of the current flowing through the creeping discharge body l is as shown in FIG. This medium waveform a is a main component, which is a charging/discharging current flowing in a capacitor component between discharge electrodes, and has a frequency of 20 KHz to 40 KHz. The waveform is a pulsed noise of 1 μsec (1 MHz or more) or more that is superimposed on the main component due to discharge in the air. This component is proportional to the discharge intensity in the air. Therefore, in the embodiment, the creeping discharge body 1 is
The filter 10 extracts only the pulse component, which is amplified by the transistor 7, further rectified by the diode D, and the smoothed DC voltage is fed back to the transistor 8 by the smoothing circuit 11. When the voltage is large, the self-assisted oscillation is weakened, and when the feedback voltage is small, the automatic oscillation is strengthened, resulting in a constant discharge amount through feedback control.

Note that the feedback response speed is stabilized by the time constant of the resistor R2 and the capacitor C1.

FIG. 7(A) and FIG. 7(B) show the ozone generation characteristics with and without the humidity measures of this example, and it is clear that a remarkable effect is recognized.

Embodiment of Claim 3> FIG. 4 is a circuit connection diagram of an ozone generating circuit according to an embodiment of the invention of Claim 3. In the figure, Pl is a + power supply connection terminal, a fan (not shown) is connected to terminals P2 and P4, and a pulse signal corresponding to the rotation speed of the fan is derived from terminal P3. This terminal P3 has capacitors C5, R,
An integrator circuit is constructed, and this terminal P3 is OR
Flip-flop 14 via circuit 12 and AND circuit 13
is connected to the set input terminal S of. When the switching waveform of the terminal P3 exceeds the threshold level, the flip-flop 14 detects an abnormality in the fan and sets the flip-flop 14. Similarly, a part of the current (20 KHz) of the surface discharge body 1 is taken out by the resistors Rs and Rh and applied to the set input terminal S of the flip-flop 14 via the OR circuit 12 and AND13. Normal time 2
Resistors R& and R5 are selected so that the threshold voltage of the flip-flop 14 is achieved with a current that is approximately twice as large.

Further, a timer 16 is provided, and the rising voltage when the power is turned on is input to the timer 16 through a resistor R, and an OR circuit 15.
is reset, and then logic is input to the AND circuit 13 in 2 seconds.
111, and resets itself via the OR circuit 15 with the output of "10 minutes".

The output terminal Q of the flip-flop 14 is connected to the ON10 FF switch 17.18, and the set output Q=''
1" ON10 FF switch 17.18 OFF
It is supposed to be done.

In this embodiment of the ozone generation circuit, assuming that the fan is currently rotating normally, the waveform input to terminal P3 is up to tl in FIG.
The human power to T) does not exceed the threshold level T)l, so the flip-flop 14 is not set. However, when the rotational speed of the fan decreases to 60 rpm or less, the threshold level TH is exceeded and the flip-flop 14 is set, as shown at time t2 in FIG.
The set output Q causes switches 17 and 18 to turn OFF.
The fan is turned off, the discharge is stopped, and the power supply to the fan is also cut off. However, as mentioned above, the operation starts about 2
Since one end of the AND circuit 13 does not reach "1°" during the second period, the flip-flop 14 is not set and therefore the cutoff function does not work.

Furthermore, even if the fan is operating normally, if an abnormally large current flows due to water droplets, etc., the voltage input to the OR circuit 12 will become large due to the resistors R2 and R4, exceeding the threshold level and causing the flip-flop 14 to flow. Enter. This set output turns off the switch 17, stopping the discharge, and likewise turns off the switch 18, causing the fan to stop operating.

Note that the flip-flop 14 is reset by a 10-minute signal from the timer 16, and in the case of an instantaneous abnormality, it can be used again after 10 minutes.

Further, FIG. 6 shows an ozone generation circuit incorporating all the circuits shown in FIGS. 1, 2, and 4.

(F) Effect of the Invention According to the invention of claim 1, since the power source for driving the piezoelectric element is derived from the tap of the step-up transformer,
It is possible to obtain an ozone generation circuit that does not require a separate special power source for driving the piezoelectric element, is inexpensive, and can apply a required voltage according to each specification.

According to the second aspect of the invention, a discharge current detection circuit detects the current flowing through the creeping discharge body, and from the detected current, only a discharge component generated in proportion to the air discharge is derived by a filter circuit. The signal of this frequency component is fed back to control the discharge current and keep it constant, so even if changes in solubility or temperature occur, feedback control is applied to prevent changes in discharge amount due to changes in solubility or temperature. is always kept constant.

According to the third aspect of the present invention, a fan stop abnormality and a discharge abnormality are detected, and the circuit is cut off in either of the abnormalities, for example, the fan is stopped or the discharge is stopped, so that even if an abnormality occurs,
This has the advantage of preventing leakage of high-concentration ozone, abnormal ozone generation, and adverse effects caused by heat generation of circuit components.

[Brief explanation of drawings]

FIG. 1 is a circuit connection diagram of an ozone generation circuit showing an embodiment of the invention of claim 1, FIG. 2 is a circuit connection diagram of an ozone generation circuit showing an embodiment of the invention of claim 2, and FIG. 4 is a circuit diagram showing an ozone generation circuit according to an embodiment of the invention according to claim 3. FIG. 5 is a waveform diagram for explaining the operation of the ozone generation circuit. FIG. 6 is a waveform diagram for explaining the operation of claim 1, and FIG.
FIG. 7(A) is a diagram showing the ozone generation characteristics in the case with humidity measures, and FIG. 7(B) is a diagram showing the ozone generation characteristics in the case without humidity measures. l: creeping discharge body, 2: piezoelectric element, 3: step-up transformer, 9: discharge current detection circuit, 10: filter, 14: flip-flop, 17/18: switch. Figure 1 Patent Applicant Nishin Engineering Co., Ltd. Agent Patent Attorney Shigeru Nakamura Shin 3:! ! Hill transformer diagram (A)

Claims (3)

[Claims] (1) In an ozone generation circuit that generates ozone by applying a voltage boosted by a drive transformer to a creeping discharge body, and also includes a piezoelectric element attached to the creeping discharge body for removing deposits, dirt, etc. . An ozone generation circuit, characterized in that a tap voltage is taken out from the winding of the drive transformer and applied to the piezoelectric element. (2) In an ozone circuit that generates ozone by applying a voltage boosted by a drive transformer to a creeping discharge body, a discharge current detection circuit that detects a discharge current flowing through the creeping discharge body, and a discharge current detection circuit that detects a discharge current flowing through the creeping discharge body; 1. An ozone generation circuit comprising: a filter circuit that derives only components in a frequency region; and a feedback circuit that controls the discharge current by feeding back the output of the filter circuit. (3) a fan stop detection circuit that applies a voltage boosted by a drive transformer to a creeping discharge body to discharge it and generate ozone, and detects a stop of the fan in an ozone generation circuit that is provided with a fan; Alternatively, an ozone generation circuit comprising: a discharge abnormality detection circuit that detects an abnormality in the discharge circuit of the creeping discharge body; and a circuit that interrupts the circuit in response to the fan stoppage detection and/or the discharge abnormality detection.