JPS599730Y2 - Ultrasonic atomizer - Google Patents

Description

[Detailed description of the invention] The present invention relates to an ultrasonic atomization device that vibrates a vibrator at high frequency and uses this vibrator to emit ultrasonic waves into a liquid to atomize the liquid. The present invention provides an ultrasonic atomization device that uses a light emitting diode or a neon tube to notify a malfunction when the device does not operate normally.

An ultrasonic atomizer is a device that atomizes liquid into fine particles by driving a piezoelectric vibrator attached to the bottom of the liquid to be atomized using an oscillation circuit and emitting ultrasonic waves above the liquid surface. It is.

Recently, demand for such ultrasonic atomization devices has been increasing for use in humidification and atomization of chemical solutions.

FIG. 1 shows the circuit of the main part of a conventional ultrasonic atomizer.

In Fig. 1, 1a and 1b are single-phase AC power input terminals,
2a, 2b, 2C, and 2d are diodes constituting a rectifier circuit, 3 is a capacitor for noise removal, 4 is an output terminal of the rectifier circuit, and 5 and 6 are voltage dividing resistors that apply a bias voltage to the transistor 7.

8, 9, and 10 are capacitors, 11 is a resistor, and 12 is a vibrator, which monitor the Colpitts oscillation circuit.

13 is a choke coil provided in the oscillation circuit, 14
is the collector terminal of the transistor 7, and 15 is a power switch.

In the circuit with the above structure, an alternating current voltage shown in FIG. The rectifier circuit performs full-wave rectification as shown in Figure 2b.

That is, the capacitor 3 has a small capacitance of about 0.02 μF, and is provided for the purpose of removing noise from the oscillation circuit, and the output terminal 4 has a full-wave rectified waveform voltage shown in Fig. 2b. It appears as it is.

In addition, a high frequency voltage generated by an oscillation circuit composed of a transistor 7, capacitors 8, 9, 10, a resistor 11, and an oscillator 12 is connected to the collector terminal 14. The voltage waveform shown in Figure C appears.

The vibrator 12 performs high frequency vibration as shown in FIG. 2C and emits ultrasonic waves into the liquid.

If the vibrator 12 stops vibrating due to a failure such as breakage of the lead wire to the vibrator 12 or deterioration of the vibrator 12, an excessive current will flow through the transistor 7 and the transistor 7 will be destroyed.

If you do not notice this and leave it unattended, there is a risk that the ultrasonic atomizer may catch fire.

The present invention eliminates the above-mentioned conventional drawbacks, and when the oscillator stops vibrating due to a failure, the failure is immediately notified with a light emitting diode or neon tube, and the bias voltage of the oscillation transistor is set to zero. The present invention provides an ultrasonic atomization device that can turn off the oscillation transistor and protect the oscillation transistor and other circuit components.

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

FIG. 3 is a circuit diagram of an ultrasonic atomizer according to an embodiment of the present invention.

This circuit is the basic circuit of the conventional ultrasonic atomizer shown in FIG. A light emitting diode 17 is connected thereto.

Now, when the oscillation circuit is operating normally and the vibrator 12 is vibrating, a voltage is generated between the output terminals of the secondary winding 16 and the light emitting diode 17 lights up.

The user of the ultrasonic atomization device sees that the light emitting diode 17 is lit and recognizes that the device is operating normally.

Next, when the connection lead to the vibrator 12 is broken or the vibrator 12 stops vibrating due to other circuit abnormalities, the secondary winding 16
Since no voltage is generated between the output terminals of the light emitting diode 17
When the user of the ultrasonic atomization device saw that the light emitting diode 17 had gone out, he knew that the device was malfunctioning, and immediately opened the power switch 15 and turned on the oscillating transistor 7.
can prevent thermal runaway, etc.

Next, another embodiment shown in FIG. 4 will be explained.

In this embodiment, a protection circuit 18 shown by a broken line is added to the conventional basic circuit shown in FIG.

In the protection circuit 18, 16 and 17 are 2 as in FIG.
The next winding and the light emitting diode, 19 constitutes a photo coupler together with the light emitting diode 17.
20 and 21 are diodes and capacitors that smooth the voltage appearing at the output terminal 4 of the rectifier circuit made up of diodes 2a to 2d; 22, the base of which is connected to the collector of the phototransistor 19; 23 is a resistor provided at the collector of the phototransistor 19.

The diode 20 and the capacitor 21 convert the voltage appearing at the output terminal 4 into a DC voltage, and supply the second DC voltage to the collector of the phototransistor 19 via the resistor 23.

The light receiving surface of the phototransistor 19 is directed toward the light emitting diode 17, and the emitter of the phototransistor 19 is grounded, and its collector is connected to the resistor 23 and the base of the transistor 22.

In the above circuit configuration, when the oscillation circuit is operating normally and the vibrator 12 is vibrating, a voltage is generated between the output terminals of the secondary winding 16 and the light emitting diode 17 is lit, so the phototransistor 19 is in the on state.

Therefore, the collector voltage of the phototransistor 19 becomes zero, the base voltage of the transistor 22 also becomes zero,
A normal bias voltage is applied to the transistor 7 from the output terminal 4 of the rectifier circuit, and the vibrator 12 continues to vibrate normally.

Further, the user of the ultrasonic atomization device can see that the light emitting diode 17 is lit and know that the device is operating normally.

Next, when the vibrator 12 stops vibrating due to breakage of the lead wire to the vibrator 12 or other circuit abnormality, the light emitting diode 17 is turned off and the phototransistor 19 is turned off.

Therefore, the collector potential of transistor 19 becomes high, the base voltage of transistor 22 also becomes high, and transistor 22 is turned on.

As a result, the base bias voltage of the oscillation transistor 7 becomes zero, and the oscillation transistor 7 is turned off.

Therefore, the oscillation transistor 7. Thermal runaway can be prevented, and subsequent damage to other circuit components can also be prevented.

Further, the user of the ultrasonic atomization device sees that the light emitting diode 17 is off and knows that the device is out of order and opens the power switch 15.

In this case, since the oscillation transistor 7 is already in the OFF state, even if it takes time for the user to open the power switch 15 after the light emitting diode goes out, the circuit components of the ultrasonic atomizer Damage is preventable.

In the above two embodiments, a light emitting diode was connected to the output terminal of the secondary winding, but a neon tube may be connected instead of the light emitting diode.

As explained above, the ultrasonic atomizer of the present invention can be realized by simply adding a simple circuit to the basic circuit of a conventional ultrasonic atomizer. When the vibration of the oscillator stops, the user is notified of the abnormal condition through a display such as a light emitting diode, and the oscillation transistor is turned off to protect the oscillation transistor and other circuit components.

[Brief explanation of the drawing]

Figure 1 is the basic circuit diagram of a conventional ultrasonic atomizer, Figure 2a
, l), and c are voltage waveform diagrams at various points in the circuit of Fig. 1, Fig. 3 is a circuit diagram of an ultrasonic atomization device in one embodiment of the present invention, and Fig. 4 is another embodiment of the present invention. FIG. 2 is a circuit diagram of an ultrasonic atomization device in FIG. la, lb... AC power input terminal, 2a, 2b
, 2C, 2d... Diode, 7...
Oscillation transistor, 12... Vibrator, 13.
...Choke coil, 16, curved, secondary winding, 17
. . . Light emitting diode, 18 . . . Protection circuit, 19 . . . Phototransistor.

Claims (2)

[Scope of utility model registration request] (1) An ultrasonic atomizer comprising a rectifier circuit that rectifies single-phase alternating current, and an oscillation circuit that uses the output voltage of the rectifier circuit as a power supply voltage, the ultrasonic atomizer having a choke coil installed in the oscillation circuit. 1. An ultrasonic atomizer comprising a winding and a light emitting diode or neon tube connected to the output terminal of the secondary winding. (2) The light emitting diode or neon tube is equipped with a phototransistor forming a photocoupler, and when the oscillation of the oscillator of the oscillation circuit stops due to a failure, the presence or absence of the output voltage of the phototransistor is detected, and the output voltage of the oscillation circuit is detected. 2. The ultrasonic atomization device according to claim 1, further comprising a protection circuit for lowering the base voltage of the oscillation transistor.