JP2769139B2 - Ozone generation circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an ozone generation circuit for generating ozone by applying a high voltage to a surface discharger.

[0002]

2. Description of the Related Art In an ozone generator, a high voltage obtained by boosting an AC signal from a self-excited oscillator with a boosting transformer is applied to a creeping discharger having a fine ceramic dielectric layer, and air is discharged by discharging the creeping discharger. Some of them are made to react to obtain ozone. In this type of ozone generator, a piezoelectric element is provided to solve the problems at the time of discharge, such as prevention of deposits (dirt) on the ozone generating discharge body and improvement of nitrate mist. (See Japanese Patent Application Laid-Open No. 62-2016).
No. 38, No. 63-190702).

[0003]

The above-mentioned conventional ozone generating apparatus is provided with a fan and blows air to output a predetermined amount of generated ozone uniformly. However, if the fan is stopped due to a failure during the generation of ozone, ozone is not output properly, and ozone concentration is generated depending on the region, high concentration ozone is only good near the device, there is a health problem, and They may remain in the device and adversely affect circuit elements.
Even if the fan is rotating, an excessive current flows due to the abnormal discharge of the creeping discharge body, and there is a risk of ignition, and since the high voltage is used, the apparatus may be damaged if the abnormal discharge is left unattended. Furthermore, if only the fan is rotating even though ozone is not normally generated, there is a possibility that a misunderstanding may appear to appear as if the device is operating normally. However, the conventional ozone generator has no means for coping with the abnormality, and has a problem in reliability and safety.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a highly reliable ozone generation circuit that detects an abnormality and operates safely when the abnormality occurs. I have.

[0005]

An ozone generation circuit according to the present invention comprises an ozone generation circuit provided with a fan while applying a voltage boosted by a drive transformer to a creeping discharger to generate ozone by discharging. and fan stop detection circuit for detecting a stop of the fan, a discharge abnormality detection circuit for detecting the detected and abnormal discharge the discharge current of the discharge circuit of the creeping discharge member, the discharge circuit in response to the fan stop detection
To stop discharging, and in response to the discharge abnormality detection,
A fan and a circuit for stopping discharge of the discharge circuit are characteristically provided.

In this ozone generation circuit, when the rotation of the fan is stopped (including low speed), this is detected by the fan stop detection circuit. Further, when the discharge current of the creeping discharge body becomes equal to or more than a predetermined value (abnormal discharge and short circuit), it is detected by the discharge abnormality detection circuit. When the fan stop detection or the discharge abnormality is detected, the fan is stopped and the operation of the discharge circuit is stopped. Thus, continuation of the operation in the abnormal state is avoided.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to embodiments. FIG. 1 is a circuit connection diagram of an ozone generation circuit according to an embodiment of the present invention. In the figure, P ₁ is + power connection terminal, the terminal P ₂ and the terminal P ₄ fan (not shown) is connected to the P _3, a pulse signal corresponding to the rotation speed of the fan is derived. The terminal P ₃ is provided with an integrating circuit composed of capacitors C ₅ and R ₇ , and the terminal P ₃ is connected to the set input terminal S of the flip-flop 14 via the OR circuit 12 and the AND circuit 13. Flip-flop 14, the switching waveform of the terminal P ₃ exceeds the threshold level, to detecting an abnormality of the fan, setting the flip-flop 14. Similarly, a part of the current (20 KHz) of the creeping discharger 1 is taken out by resistors R ₅ and R ₆ , and the OR circuit 12, AND
13 to the set input terminal S of the flip-flop 14. The resistance R is set so that the threshold level voltage of the flip-flop 14 becomes about two times the current in the normal state.
_6, select the R _5. Further, a timer 16 is provided, and a rising voltage when the power is turned on is set by a resistor R ₈ and an OR circuit 1.
5 resets the timer 16 and then 2 seconds
The logic "1" is input to the D circuit 13, and the output of "10 minutes" resets itself through the OR circuit 15. The output terminal Q of the flip-flop 14 is an ON / OFF switch 1
7 and 18 and are set to O when set output Q = "1".
The N / OFF switches 17 and 18 are turned off.

In the ozone generation circuit of this embodiment, assuming that the fan is now rotating normally, the waveform input to the terminal P _{3 is} that until t _{1 in} FIG. The input also does not exceed the threshold level TH. Therefore, flip-flop 14 is not set. However, when the rotation 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 t ₂ in FIG. 2, and the switches 17 and 18 are set by the set output Q.
Is turned off, the discharge is stopped, and the power supply to the fan is cut off. However, as described above, since one end of the AND circuit 13 does not become "1" for about two seconds from the start of operation, the flip-flop 14 is not set, and thus the cutoff function does not work.

Even when the fan is operating normally, if an abnormally large current flows due to water drops or the like, the voltage input to the OR circuit 12 increases due to the resistors R ₅ and R ₆ , and the voltage exceeds the threshold level. , The flip-flop 14 is set. With this set output, switch 17
FF is performed, the discharge is stopped, and the switch 18 is similarly turned OFF.
F, the fan also stops operating.

Note that the flip-flop 14 is provided with the timer 1
Reset by 10 minutes signal of 6 and 1 in case of instantaneous abnormality
It can be used again after 0 minutes. FIG. 3 is an overall circuit of the ozone generator in which the ozone generation circuit of the above embodiment is incorporated. The main circuit in FIG. 1 corresponds to the circuit part 32 in FIG. Hereinafter, in FIG. 3, circuits other than the circuit part of FIG. 1 will be described.

In FIG. 3, a circuit portion 30 is shown in FIG.
1 shows a fine circuit.
Creepage discharge for ozone generation used for the dielectric layer.
The piezoelectric element 2 is attached for preventing an object (dirt) or the like.
Secondary winding N of step-up transformer 3 _sAre both electrodes of the surface discharger 1.
Connected directly to point A of the primary winding of the step-up transformer 3.
One end of the DC power supply 4 is connected, and the other end of the DC power supply 4 is connected to the transformer.
Step-up transformer 3 through the emitter and collector of transistor 6
Are connected to point B of FIG. Note that the transistor 6
The oscillation source 5 is connected to the source. Also, boost transformer
3 is the winding N_P1And the winding N_P2Increased
Then, tap C and tap A are connected to the piezoelectric element 2.
ing.

In this ozone generation circuit, a DC power supply 4
Is self-oscillating including the transformer 3 in response to the turning on / off of the transistor 6 by a signal from the oscillation source 5, and the voltage V ₁ boosted by the boosting transformer 3 at a ratio of N _s / N _P1. Is applied to the surface discharger 1, and the surface discharger 1
Is discharged, and at that time, the air reacts to generate ozone.
Further, a winding N _P1, was Masa further wound to the winding N _P1 N
Voltage V ₂ by the _P2 is applied to the piezoelectric element 2, vibrating the piezoelectric element 2.

With this circuit, the voltage of the power supply 4 is
And then, the discharge voltage V ₁ = 2800V _PP, at 19.5KHz the frequency of the oscillation sources 5, the voltage V ₂ of the piezoelectric element 2 was obtained 50 V _PP (sine wave), and the vibration effect thereby intended . In the prior art, when a piezoelectric element drive circuit is provided separately from the step-up transformer 3, the frequency is 17 KHz, 20 KHz.
This is a remarkable advance compared to the case where only the control up to V _PP was possible and the vibration effect was extremely small.

In FIG. 3, a circuit portion 31 is a specific circuit shown in FIG. 5, and includes a resistor R ₄ , a capacitor C ₃ ,
The transistor 6, the step-up transformer 3, and the surface discharger 1 constitute a transformer-coupled self-oscillation circuit, and apply a high voltage to the surface discharger 1. Step-up transformer 3
One end of the secondary winding N _s is GND (ground) connected through a resistor R ₅ in. Constitute the discharge current detection circuit 9 in this resistor R _5. Step-up transformer N _s and one end of the capacitor C ₁ to the connection point of the resistor R ₅ is connected, the capacitor C ₁
The other end of which is connected to the base of the transistor 7, the resistor R ₁ is connected between the other end and GND of the capacitor C _1. Filter 1 In this capacitor C ₁ and resistor R ₁
0. Transistor 7 is provided to amplify the signal from the filter 10, the emitter is connected to GND, and is connected collector through a resistor R ₃ to the + 12V supply. A rectifier diode D is connected to the collector of the transistor 7,
A capacitor C ₂ and a resistor R ₂ are connected to the output side of the diode D.
Are connected to the base of a transistor 8 for controlling the oscillation state of the self-excited oscillation circuit.
The resistance R ₄ is a variable resistor, it has become for adjusting the oscillation intensity.

In this circuit portion 31, the surface discharger 1
FIG. 6 shows the waveform of the current flowing through the circuit. The middle waveform a is a main component, which is a charge / discharge current flowing through a capacitor component between discharge electrodes, and has a frequency of 20 KHz to 40 KHz.
Hz. The waveform b is a pulse noise of 1 μsec (1 MHz or more) which is superimposed on the main component by the discharge in the air. This component b is proportional to the discharge intensity in air. Therefore, in the embodiment, the current flowing through the surface discharger 1 is detected by the resistor R _5, only the pulse component b is derived by the filter 10, amplified by the transistor 7, further rectified by the diode D, and smoothed. The DC voltage smoothed by the circuit 11 is fed back to the transistor 8, and when the feedback voltage is large, the self-excited oscillation is weakened, and when the feedback voltage is small, the self-excited oscillation is increased. As feedback control,
The discharge amount is constant. Note that a resistor R ₂ and a capacitor C ₂
The feedback response speed is stabilized by the time constant.

[0016]

According to the present invention, an abnormal stop of the fan and an abnormal discharge are detected, and the circuit is interrupted by any of the abnormalities, for example, the fan is stopped and the discharge is stopped. There is an advantage that it is possible to prevent leakage of concentration ozone, ozone generation abnormality, adverse effects due to heat generation of circuit components, and the like.

[Brief description of the drawings]

FIG. 1 is a circuit connection diagram showing an ozone generation circuit according to an embodiment of the present invention.

FIG. 2 is a waveform chart for explaining the operation of the ozone generation circuit of the embodiment.

FIG. 3 is a circuit connection diagram showing an entire circuit of the ozone generator in which the ozone generation circuit of the embodiment is incorporated.

FIG. 4 is a circuit connection diagram showing a partial circuit of the ozone generator.

FIG. 5 is a circuit connection diagram showing another partial circuit of the ozone generator.

FIG. 6 is a waveform chart for explaining the operation of a part of the ozone generation circuit of the embodiment.

[Explanation of symbols]

1 creeping discharge member 14 flip-flops 17 and 18 switch 22 Fan R _7, C ₅ integrator circuit

Claims (1)

(57) [Claims] 1. A voltage boosted by a driving transformer is applied to a creeping discharge body to discharge and generate ozone.
An ozone generation circuit provided with a fan, comprising: a fan stop detection circuit for detecting stop of the fan ;
A discharge abnormality detection circuit for detecting the discharge current of the discharge circuit of the serial creeping discharger detects the abnormal discharge <br/>, the fan stop detection
In response, the discharge of the discharge circuit is stopped, and the discharge abnormality is detected.
Stop discharging the fan and the discharge circuit in response to
Ozone generator, characterized in that a circuit makes.