JPS6327067B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a liquid atomization device that atomizes liquid fuel such as kerosene or light oil, water, chemical solution, recording liquid, etc. using an electric vibrator. .

Configurations of Conventional Examples and Their Problems Various types of liquid atomization devices have been proposed in the past, and many of them use electric vibrators such as piezoelectric elements.

For example, (1) a piezoelectric element is bolted or glued to a horn-shaped vibrator, the mechanical vibration amplitude of the piezoelectric element is amplified by the horn-shaped vibrator, and a liquid is supplied and dripped onto the amplitude amplifying surface at the tip of the horn. (2) A device that injects an array of ultrasonic atomized particles, which has been put into practical use in inkjet recording devices in recent years, and has a piezoelectric vibrator installed at one end of the liquid chamber. , with an orifice installed at the other end, the pressure increase in the liquid chamber due to the vibration of the piezoelectric vibrator is transmitted to the orifice via the liquid, and as a result, atomized particles can be sprayed from the orifice at a considerable scattering speed. There are atomization devices that can do this.

However, the conventional ultrasonic atomization device described above had various drawbacks.

The atomization device (1) requires high machining precision for the horn-shaped vibrator and a pump to supply the liquid, so it is expensive, and the method of supplying the liquid to the atomization surface is complicated. It was hot. Further, in order to obtain an atomization amount of 20 c.c./mm, a considerably large power consumption of 5 to 10 watts is required, and the atomization ability is not sufficient.

The atomizing device (2) had the advantage of being simple in structure and stable in operation, as is clear from the fact that it is used in inkjet. Since the configuration transmits the information to the orifice via the liquid, when a typical liquid containing a large amount of dissolved air is used, cavitation bubbles will occur in the liquid chamber, and these bubbles will prevent stable atomization operation. It had the disadvantage of being unsustainable. Therefore, in order to atomize ordinary liquids, dissolved air must be degassed, which is extremely lacking in versatility.

Purpose of the Invention The present invention aims to eliminate such conventional drawbacks, and provides an electronic atomization device that has a compact configuration, obtains a sufficient amount of atomization with low power consumption, and maintains stable atomization operation. The purpose is to provide.

Structure of the Invention In order to achieve this object, the present invention includes a body including a pressurizing chamber filled with liquid, a supply section for supplying liquid to the pressurizing chamber, and a supply section facing the pressurizing chamber. An atomizer is configured by the provided nozzle part and an electric vibrator that energizes the nozzle part to vibrate the nozzle, and a current detector that detects the current flowing through the electric vibrator. An electronic atomization device is constituted by an amplifying section that amplifies the signal from the current detector, and an inductor that transmits the signal from the amplifying section to the electric vibrator.

With this configuration, the electric vibrator forms an electric tank circuit with the inductor, and boosts the voltage supplied to the amplifier section to generate vibrations, which reduces power consumption and also feeds back the signal from the current detector. By amplifying it, a self-excited oscillation system is constructed to automatically track changes in the characteristics of the electric vibrator and maintain stable atomization operation. Furthermore, during actual atomization operation, the pressurized chamber acts as a self-sufficient liquid pump due to the vibration of the nozzle plate, making the atomizer system more compact.

DESCRIPTION OF EMBODIMENTS An atomizer which is an embodiment of the present invention will be described with reference to FIG. A body 2 including a pressurized chamber 1 filled with liquid is fixed to a mounting plate 4 with screws 3. The liquid enters the pressurizing chamber 1 through the supply pipe 5, and the gas discharge pipe 6 is filled halfway during actual atomization. Reference numeral 7 denotes a nozzle portion facing one side of the pressurizing chamber 1, and its outer periphery is joined to the body 2. A spherical protrusion 8 having a fine nozzle for ejecting droplets is formed at the center of the nozzle portion 7 . Furthermore, an annular electric vibrator, here a piezoelectric element 9, is attached to the nozzle portion 7. This piezoelectric element 9 is a piezoelectric ceramic polarized in the thickness direction, and has electrodes on the surface to be joined to the nozzle portion 7 and on the opposite surface. 10 is a lead wire for transmitting a drive signal to the piezoelectric element 9, one of which is soldered to one side of the piezoelectric element 9, and the other is connected to the body 2 with a screw 1.
1 is connected. The piezoelectric element 9 is activated by the drive signal.
When the mechanical vibration is excited, the nozzle part 7 is also urged and vibrated, and as a result, the liquid in the pressurizing chamber 1 is discharged as atomized particles 12.

Incidentally, the liquid supplied to the pressurizing chamber 1 may be filled halfway into the gas discharge pipe 6 in the atomizer installation configuration, but as an alternative, the liquid supplied to the pressurizing chamber 1 may be and the exhaust pipe 6 is empty, for example, the exhaust pipe 6 is empty before entering the droplet ejection sequence.
Negative pressure may be applied through the pressure chamber 1 to fill the pressurized chamber 1 with liquid, and at the same time, the exhaust pipe 6 may be pulled up halfway.
According to the latter method, impurities in the liquid solidify in the nozzle, and the problem that droplets cannot be ejected does not occur.

Next, referring to FIG. 2, the driving configuration of the atomizer shown in FIG. 1 will be explained. Reference numeral 13 denotes an amplifying section that amplifies a signal from a current detector 14 that detects the current flowing through the electric vibrator 9, and transmits a drive signal to the electric vibrator via an inductor L15.

FIG. 3 is an electrical equivalent circuit that approximates the electrical vibrator 9, with 16 equivalent parallel capacitances.
Cs, series inductance Lo of 17, 18, and 19, capacitance Co, and resistance Ro. The inductor L in Figure 2 is the equivalent parallel capacity
A series resonance configuration with Cs as the main component is selected so that it is approximately equal to the mechanical resonance point of the atomizer. This L and Cs form a tank circuit, and the drive voltage transmitted from the amplifier is boosted across the electric vibrator 9. Therefore, if the oscillation frequency of the drive circuit system determined by L and Cs is approximately matched with the mechanical resonance frequency of the atomizer, the system as a whole will consume less power and will produce an efficient and stable liquid. Spraying becomes possible.

FIG. 4 shows a specific embodiment of the present invention. The same numbers as in the previous figure indicate components having the same function. 20 is a resistor that constitutes a current detector, and this detection signal is sent to a complementary SEPP type amplifier circuit via a capacitor 21, and is transmitted via an inductor 15 by the operation of switching transistors 32 and 33 in the output stage. , are transmitted to the electric vibrator 9. The amplifier circuit includes resistors 22, 2
3, 24, 25, 27, 29, 30, transistors 26, 31, 32, 33, and capacitor 2
It consists of 8. In this closed loop, L
and an automatic oscillation circuit system with an oscillation period determined by Cs. Note that since the output stage performs a switching operation, the loss of the transistor itself is small, and the power consumption of the amplifier section is also low. In this specific example, complementary, but
For example, a configuration may be adopted in which only a switching element is provided for discharging charges from LCs.

Effects of the Invention According to the atomization device of the present invention, the following effects can be obtained.

(1) In addition to the compact configuration of the atomizer itself, the power consumption of the drive device is reduced, and the atomizer can achieve lower power consumption, that is, higher efficiency.

(2) Construct an oscillation system determined by an equivalent parallel capacitance Cs that changes according to the rate of change in the mechanical resonance point due to the temperature characteristics of the electrical vibrator, and an inductor L whose temperature characteristics are small. Therefore, resonance point tracking to maintain stable atomization operation can be automatically achieved with a simple configuration.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a main part of an embodiment of the present invention, Fig.
The figure is a block diagram showing the configuration of an atomizing device according to an embodiment of the present invention, FIG. 3 is an electrical equivalent circuit diagram of an electric vibrator, and FIG. 4 is a circuit diagram of an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Pressurization chamber, 2... Body, 5... Supply part, 7... Nozzle part, 9... Electric vibrator, 14
...Current detector, 13...Amplification section, 15...Inductor.

Claims (1)

[Claims] 1. A body equipped with a pressurized chamber filled with liquid;
a supply section for supplying liquid to the pressurizing chamber; a nozzle section provided to face the pressurizing chamber; an electric vibrator for energizing the nozzle section and vibrating the nozzle; An atomization device comprising: a current detector that detects a current flowing through an electric vibrator; an amplification section that amplifies a signal from the current detector; and an inductor that transmits a signal from the amplification section to the electric vibrator. . 2. The atomization device according to claim 1, wherein the amplification section has an output stage with a switching configuration.