JPS648589B2 - - 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, medicinal 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.

Figure 1 shows a typical electrical equivalent circuit of a piezoelectric element, with 1 inductance, 2 capacitance, and 3
A series circuit with a resistance of 4 is connected in parallel with an equivalent capacitance of 4.

FIG. 2 shows the frequency and current characteristics (A in the same figure) and the frequency and spray amount characteristics (B in the same figure) of an atomizer using a piezoelectric element. In Figure 2A, f ₁ is called the electrical resonance frequency, f ₃ is called the electrical anti-resonance frequency, and f ₂ is called the electrical anti-resonance frequency.
This is a mechanical resonance frequency located approximately between f ₁ and f ₃ . As can be seen from B, the spray amount reaches its maximum value at _f2 , which is the mechanical resonance point.

FIG. 3 shows a drive circuit configuration of a conventional atomizing device. 5 is a piezoelectric element, 6 is an inductor L ₁ for generating series LC resonance with the equivalent capacitance Co of the piezoelectric element, 7 is a signal detector that detects the current flowing through the piezoelectric element, and 8 is the signal detector This is an amplification section that amplifies the signal from. The oscillation frequency of the self-oscillation system shown in this figure is adjusted by the inductor _L1 so that it becomes a predetermined value that allows the predetermined spray amount shown in FIG. 2 to be obtained.

However, the conventional atomizing device described above had the following drawbacks.

The electrode for applying a drive signal to the piezoelectric element is
In atomizers, which are not insulated from the power source of the drive circuit system and usually have one electrode section at the same potential as the main body of the device, other signal systems (for example, combustion equipment) that have the same potential section on the main body of the device The circuit configuration for electrical signal processing was complicated due to the flame rod used as a flame detection element. Alternatively, the installation structure for electrically insulating the atomization device from the main body of the device is extremely troublesome.

OBJECT OF THE INVENTION The present invention eliminates such drawbacks of the conventional technology, and even when other electrical parts of the atomizing device are at the same potential as the main body of the device, the present invention can be performed without complicating the electrical signal processing circuit. Another object of the present invention is to provide an atomizer having a drive circuit that does not require insulating the atomizer from equipment.

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 constituted by a nozzle section having a nozzle provided therein, and an electric vibrator that energizes the nozzle section and vibrates the nozzle, and a signal detection method that detects a drive signal to the electric vibrator. an amplifier, an amplifier that amplifies the signal from the signal detector, a transformer that transmits the drive signal from the amplifier to the electric vibrator, and a transformer that resonates in series with the equivalent capacitance of the electric vibrator. Together with the inductor, it constitutes an atomization device.

With this configuration, the electric vibrator forms an electric tank circuit with the inductor and vibrates by boosting the voltage supplied from the amplifier section, thereby reducing power consumption. Furthermore, since the drive signal is transmitted via the transformer, the electric vibrator is electrically isolated from the drive circuit.

DESCRIPTION OF EMBODIMENTS An embodiment of the atomizer of the present invention will be described with reference to FIG. A body 10 including a pressurized chamber 9 filled with liquid is fixed to a mounting plate 12 with screws 11. The liquid to be sprayed enters the pressurizing chamber 9 via the supply pipe 13, and the gas discharge pipe 14 is filled halfway during spraying. Reference numeral 15 denotes a nozzle portion facing one side of the pressurizing chamber 9, and its outer periphery is joined to the body 10. A spherical protrusion 16 having a fine hole for ejecting droplets is formed at the center of the nozzle portion 15 . Further, an annular piezoelectric element 5 is bonded to the nozzle portion. This piezoelectric element 5 is made of piezoelectric ceramic polarized in the thickness direction, and has electrodes on the surface to be joined to the nozzle and on the opposite surface. Reference numeral 17 denotes a lead wire for transmitting a drive signal to the piezoelectric element 5, one of which is soldered to one of the piezoelectric elements, and the other connected to the body 10 with a screw 18. When the mechanical vibration of the piezoelectric element is excited by the drive signal, the nozzle section 15 is also energized and vibrated, and as a result, the liquid in the pressurized chamber becomes atomized particles 19 and is ejected.

By the way, the liquid supplied to the pressurized chamber may be filled halfway up the gas discharge pipe in the atomizer installation configuration, but as an alternative, in the atomizer installation configuration, the liquid supplied to the pressurization chamber and the gas discharge pipe may be filled halfway. The inside of the gas discharge pipe is empty, and before entering the droplet discharge sequence, negative pressure may be applied, for example, through the discharge pipe, and the liquid may be drawn up halfway through the pressurized chamber and the gas discharge pipe. According to the latter method, impurities in the liquid solidify in the nozzle hole, and the problem that droplets cannot be ejected does not occur.

By the way, as can be seen from FIG. 4, the piezoelectric element 5
One side of the electrode is connected to the body 1 through the nozzle part 15.
0 and further to the mounting plate 12 of the main body of the device. In other words, it can be said that the electrode on one side of the piezoelectric element is at the same potential as the main body of the device.

FIG. 5 shows an embodiment of the atomization device of the present invention. The same numbers as in FIG. 3 indicate components having the same function. 20 is a transformer that converts the drive signal from the amplifier section 8 into an inductor for adjusting the self-excited oscillation frequency.
It is received via _L1 and transmitted to the piezoelectric element 5.

FIG. 6 shows an embodiment of a specific drive circuit for the atomization device of the present invention. The same numbers as in the previous figure indicate components having the same function. A resistor 7 constitutes a signal detector, and this signal is sent to a complementary SEPP type amplifier 8 via a capacitor 21. Switching transistor 2 of this output stage
2 and 23, the inductor 6 and transformer 2
A drive signal is transmitted to the piezoelectric element 5 via 0. The amplifying section includes transistor groups 24 and 25 including the transistors 22 and 23, and resistor groups 26 and 2.
7, 28, 29, 30, 31, 32, and a capacitor 33. 34 represents a DC power supply section. The value L ₁ of the inductance 6 is the value Co ₁ obtained by converting the equivalent capacitance Co of the piezoelectric element 5 to the primary side according to the winding ratio of the transformer 20, and the oscillation frequency of the self-oscillation system is approximately determined. selected as follows.

With the configuration shown in this figure, the piezoelectric element is electrically insulated from the drive circuit section. Therefore, even if the piezoelectric element is installed in such a way that one electrode is at the same potential as the device body, there is an electrical connection between the piezoelectric element that has another power source and a signal component (such as a frame rod) that has the same potential as the device body. There is no need to pay particular attention to signal processing. Furthermore, by setting the turns ratio of the transformer to a predetermined value,
If the transformer section is also configured to step up the voltage, the DC voltage value of the amplifier section can be designed to be low, increasing the degree of freedom in selecting transistors, which are often low-voltage products.

FIG. 7 shows another embodiment of the invention. Parts with the same numbers as in the previous figure have the same functions. 35 is a capacitor for cutting DC current, which prevents excessive DC current from flowing into the output stage of the amplifier section and saturating the inductor 6 and the transformer 20. This capacitor 35 allows the design values of the allowable current value and allowable loss of the output stage of the amplifier section to be lowered.

FIG. 8 shows yet another embodiment of the invention.
This is a configuration in which the inductor 6 for frequency adjustment is installed on the secondary side of the transformer 20, and the influence of leakage inductance and capacitance of the transformer 20 can be reduced. In other words, the series resonance frequency between the capacitance Co of the piezoelectric element 5 and the value L ₁ of the inductance 6 is
It can be the oscillation frequency of a self-excited oscillation system.

Effects of the Invention As described above, the atomization device of the present invention provides the following effects.

Since the configuration transmits the drive signal from the amplifier section to the piezoelectric element via the transformer, even if the other electrical parts of the atomizer are at the same potential as the device itself, there is no need for a complicated circuit to process the signal. No need to configure. Further, there is no need to insulate the atomizing device itself from the equipment, and the configuration can be simplified.

[Brief explanation of the drawing]

Figure 1 is an electrical equivalent circuit diagram of a piezoelectric element, Figure 2A is a characteristic diagram of the drive frequency and current of an atomizer using a piezoelectric element, and Figure B is a diagram of the drive frequency and spray amount of the atomizer. FIG. 3 is a conventional drive circuit diagram, FIG. 4 is a sectional view of an atomizer according to an embodiment of the present invention, and FIG. 5 is a characteristic diagram.
The figure is a drive circuit diagram of an atomizer showing one embodiment of the present invention, FIG. 6 is a circuit diagram showing a specific example of FIG. 5, and FIG.
The figure is a drive circuit diagram of an atomizer showing another embodiment of the invention, and FIG. 8 is a drive circuit diagram of an atomizer showing still another embodiment of the invention. 5... Electric vibrator, 6... Inductor, 7... Signal detector, 8... Amplifying section, 9... Pressurizing chamber, 10... Body, 13... Supply section, 15... Nozzle section.

Claims (1)

[Claims] 1. A body equipped with a pressurized chamber filled with liquid;
a supply unit that supplies liquid to the pressurizing chamber; a nozzle unit provided facing the pressurizing chamber; an electric vibrator that energizes the nozzle unit to vibrate the nozzle; a signal detector that detects a drive signal to the vibrator; an amplification section that amplifies the signal from the signal detector; a transformer that transmits the drive signal from the amplification section to the electric vibrator; An atomization device consisting of an inductor that resonates in series with the equivalent capacitance of an oscillator. 2. The atomization device according to claim 1, wherein the drive signal from the amplifier section is transmitted to the transformer via a DC cut capacitor.