JPS6054761A - Atomizer - Google Patents

Abstract

PURPOSE:To spray stably liquid with small-sized constitution and low electric power and to prevent outflow of the liquid from nozzles, etc. with a device for filling the liquid into a pressurizing chamber, oscillating the same with an electrical oscillator and spraying the liquid from the nozzles by providing specifically a means for transporting the liquid. CONSTITUTION:An atomizing part 13 is constituted by adhering a body 15 having a cylindrical pressurizing chamber 14, a nozzle plate 17 provided with plural nozzles 16 and a circular piezoelectric oscillator 19 as shown in the figure. The chamber 14 is provided with a supply port 22 and a discharge port 23; the former is connected to a liquid storage tank 26 and the latter to an electrically driven plunger type pump 27 which is a means for transporting the liquid, respectively by means of pipes. The outlet side of the pump 27 is connected to the tank 26 by a pipe. When the liquid is filled in the tank 26 up to the liquid level B and the pump 27 is started in this stage, the liquid level A is risen by the suction force thereof and the inside of the chamber 14 is filled with the liquid. The inside of a discharge pipe 25 is further filled with the liquid, by which the liquid is discharged to a discharge pipe 28.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an atomizer for atomizing liquid fuels such as kerosene and light oil, water, and liquids such as chemical solutions. The present invention relates to a piezoelectric spraying device configured to vibrate liquid filled in a pressurized chamber using a mechanical vibrator and spray the liquid from a nozzle.

Structures of conventional examples and their problems Hitherto, this type of atomization device has been put into practical use mainly as an ink ejection device for inkjet recording devices, but as is well known, these have a simple structure. A droplet array was generated in response to an electrical signal to print characters, etc. Therefore, it is only capable of ejecting a small amount of specially treated ink, and is not an atomizing device that can be used in the industrial field mentioned above. However, in recent years, a spraying device as shown in FIG. 1 has been proposed.

In the figure, a nozzle plate 4 provided with a plurality of nozzles 3 is attached to one end of a body 2 having a pressurizing chamber 1.
At the other end of the pressurizing chamber 1, which has a large cross-sectional area, a diaphragm 5 and a piezoelectric ceramic 7 and 6 are bonded to each other and attached to the body 2 as shown in the figure.

As shown in the figure, a supply pipe 7 and an exhaust pipe 8 are connected to the bottom of the pressurizing chamber 1, and are connected to a tank 9 and a suction port 11 of a fan 10, respectively.

When the fan 10 is stopped, the liquid level A in the supply pipe 7 is at the same height as the tank liquid level B, but when the fan 10 is started,
Negative pressure is generated at the suction port 11 . The liquid level A is pulled down by this negative pressure and becomes balanced at the liquid level C in the exhaust pipe 8, so that the inside of the pressurizing chamber 1 is filled with liquid as shown in the figure.

Next, the AC voltage shown in FIG. 2 is supplied to the electrodes (not shown) of the piezoelectric ceramic 7 and 6.

When the AC voltage shown in FIG. 2 is supplied between the adhesive surface of the piezoelectric ceramic 6 and the diaphragm 5 and the electrodes provided on the opposite side thereof, the piezoelectric ceramic 6 and the vibration waves 5, as shown in the figure, are applied. Flexural vibrations as shown by the broken line are generated to vibrate the liquid in the pressurizing chamber 1.

The pressure of the liquid due to this vibration is increased by 1 in the vicinity of the nozzle 3 due to the horn shape of the pressurizing chamber 1, resulting in a high pressure.
2 was to be injected.

This type of atomization device has a compact structure and can operate with extremely low power consumption.
It had an excellent feature of being able to easily adjust the amount of spray by simply controlling the AC voltage.
It had the following drawbacks.

Since the pressurized chamber 1 is filled with liquid using the negative pressure generated by the fan 10, the liquid level C is adjusted so that this negative pressure -P is balanced with the height h between the liquid levels A and C. The height of is determined. In other words, the density (specific amount) of the liquid is 0.
Expressed as p=pXh, there is a balance.

For this reason, the negative pressure -P generated by the fan 10 requires, for example, a negative pressure of P = 50 un H20 when the liquid is water and h' = 50 mm, which requires a considerably high pressure generation ability. It was necessary to have a fan. For this reason, the fan 10 has disadvantages in that it generates noise and is large in size since it is required to be at high speed. Also, the suction height h
varies depending on the density ρ of the liquid, and the position of the liquid level A is determined by the height of the liquid level B in the tank 9. Therefore, the height of the liquid level C depends on the density e of the liquid and the liquid level B in the tank 9. It is affected by the height, and in extreme cases, the liquid level C may drop to the inside of the pressurizing chamber 1, or conversely, it may rise too high and the fan 10
There was an inconvenience that liquid may flow into the suction port 11 of the pump.

If the fan 10 is suddenly stopped from the state shown in FIG. 1, the pressure (positive pressure) due to the liquid in the exhaust pipe 8 will be applied to the liquid in the pressurizing chamber 1. That is, when the height from the nozzle 3 to the liquid level C is hh, the internal pressure Pin of the liquid near the nozzle 3 is Pin-ρxhh.

Therefore, the liquid overflows from the nozzle 3, and the spraying operation becomes unstable due to the overflowing liquid.

OBJECTS OF THE INVENTION The present invention provides an atomizing device that eliminates such conventional drawbacks.

The first objective is to have a compact configuration, and regardless of the height difference between the liquid tank and the pressurizing chamber or the density of the liquid,
An object of the present invention is to provide an atomizing device capable of reliably filling a pressurized chamber with liquid and stably atomizing it with extremely low power.

The second purpose is to completely prevent the inconvenience of liquid leaking out from the 7' nozzle or exhaust pipe, and to create an atomizing device that does not cause contamination of the equipment or instability of the spray operation. It is to provide.

Structure of the Invention In order to achieve the above object, the present invention has the following structure.

That is, a body having a pressurizing chamber, a nozzle facing the pressurizing chamber, an electric vibrator that vibrates the liquid in the pressurizing chamber and sprays it from the nozzle, a tank for storing the liquid, and a liquid sending means. In addition, a supply port and a discharge port are provided in the pressurized chamber,
The pressurized chambers are filled with liquid by connecting both sides to a tank and a liquid sending means, respectively.

Therefore, the liquid is sent from the tank to the supply port, the pressurizing chamber, the discharge port, and then to the liquid sending means, so that the pressurizing chamber is filled with liquid, and by the vibration of the electric vibrator. It is sprayed from a nozzle and atomized.

Explanation of Examples] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 is a sectional view of an atomizing device showing one embodiment of the present invention.

In FIG. 3, the atomizing section 13 has a diameter of 5 to 15 mm inside.
body 15 having a cylindrical pressurizing chamber 14 with a depth of about 1 to 5 mm, and a diameter of 30/'nt to 100/l.
Equipped with a plurality of nozzles 16 with a diameter of about 30 mm and a thickness of 30 mm or more.
A nozzle plate 17 of about 100 fi m and an outer diameter of 5 to 15
A disc-shaped piezoelectric vibrator 19 having an opening 18 with a thickness of 0.5 to 2 is bonded to each other as shown in the figure, and is fixed to a mounting plate 21 with screws 20. There is.

The pressurizing chamber 14 is provided with a supply port 22 and a discharge port 23,
They are connected to a supply pipe 24 and a discharge pipe 25, respectively.

The supply port 24 is connected to a tank 26 that stores liquid,
On the other hand, the discharge pipe 25 is connected to a plunger type electrically driven pump 27 which is a liquid feeding means. therefore,
The liquid is sent from the tank 26 through the supply pipe 24 and the supply port 22 to the pressurizing chamber 14, and further flows through the discharge port 23 and the discharge pipe 25 to the pump 27. By the operation of the pump 27, the liquid is sucked out from the tank 26 and sent to the prosecutor's office. A discharge pipe 28 is connected to the outlet side of the pump 27, and the distal end of the discharge pipe 28 is connected to the tank 26 as shown in the figure.

When the tank 26 is filled with liquid at liquid level B, the liquid level A in the supply pipe 24 is at the same height as B as shown in the figure. When the pump 27 is activated, the liquid level A rises due to its suction force, and the inside of the pressurizing chamber 14 is filled with liquid. Then, the liquid level A further rises, the inside of the discharge pipe 25 is also filled with liquid, and the liquid is further discharged into the discharge pipe 28. In this way,
When the pump 27 operates, the liquid in the tank 26 is sucked up to form a liquid circulation system as shown by the arrow in the figure.

In this state, the pressure inside the pressurizing chamber 14 is reduced by the pump 27.
, the position (height) relationship between the tank 26 and the atomizing section 13, and the supply pipe 24, discharge pipe 25, and discharge pipe 2.
A constant negative pressure is determined by the flow path resistance of 8.

Therefore, the liquid is prevented from flowing out from the nozzle 16.

The piezoelectric vibrator 19 is provided with electrodes (not shown), and the electrodes are formed on the adhesive surface to the nozzle plate 17 and the surface opposite thereto.

When an alternating current voltage as shown in FIG. 4a, b, or c is supplied between these electrodes, the piezoelectric vibrator 19 undergoes expansion and contraction strain in its diametrical direction depending on the polarity of the voltage. Since the piezoelectric vibrator 19 is bonded to the nozzle plate 17, this radial expansion/contraction strain is converted into flexural vibration as shown by the broken line in the figure, and as a result, the nozzle 16 moves in its axial direction, that is, in FIG. vibrates in the left and right direction.

Therefore, the liquid in the pressurizing chamber 14 is excited and the pressure increases, and the liquid i29 flies from the nozzle 16.

Piezoelectric vibrator 19 required to perform such a spraying operation
For example, when spraying kerosene at a rate of 10 cc/mj n, the power consumption is approximately 0.63 Watts,
It can be sprayed stably with very low power and without being affected by cavitation bubbles. This is because air bubbles (not shown) generated near the center of the nozzle plate 17 due to cavitation are repelled toward the outer circumference inside the pressurizing chamber 14 due to the vibration mode shown in the figure. Because of the arrow-like flow of liquid,
It is discharged from the pressurized chamber 14 through the discharge pipe 25, pump 27, and discharge pipe 28 into the air inside the tank 26. In order to achieve such a smooth discharge of bubbles, it is necessary to eliminate the area between the pressurizing chamber 14 and the inlet of the pump 27 where bubbles tend to accumulate, and the discharge pipe 25 is As you move toward the pump 27, its height decreases at least (that is, it is horizontal or gradually increases).
It is configured as follows.

The amount of spray from this atomizer can be easily adjusted by simply controlling the alternating current voltage supplied to the piezoelectric vibrator 19 as shown in FIG. 4a, b, or c.

Since the pump 27 only has to perform the function of sucking up liquid from the tank 26 and filling the pressurizing chamber 14, it has only the ability to suck up liquid from a height of, for example, 50 to 100 mm. The accuracy of the ability may be coarse.

This is because the amount of spray from the atomizer 13 is determined by the power supplied to the piezoelectric vibrator 19-\, and the volume of liquid equivalent to the atomized liquid is determined by the surface tension of the liquid generated in the nozzle 16. There is no way that the supply pipe 24 will naturally suck it up. Therefore, by constructing an atomizing device as shown in Fig. 3 using a very low-power, low-cost, and compact pump 27, the difference in height between the tank and the pressurizing chamber and the change in the density of the liquid can be It is possible to provide an atomizing device that does not generate an air layer in the pressurizing chamber 14 or that liquid leaks out of the device, and can perform extremely stable atomizing operations. As is clear from the explanation J above, the pressure inside the pressurized chamber 14 is always lower than the outside air pressure of the nozzle 16, so liquid may overflow from the nozzle 16 to the outside. It is possible to provide an atomizing device that does not cause liquid to overflow from the nozzle and contaminate the outside, or that the atomizing operation does not become unstable due to bathing liquid.

FIG. 5 is a sectional view of an atomizing device showing another embodiment of the present invention, and the same reference numerals as in FIG. 3 indicate corresponding structures, and their explanation will be omitted.

In the figure, a supply port 22 and a discharge port 23id are both provided on the bottom surface of the pressurizing chamber 14 facing the nozzle plate 17, and are configured to be connected to the discharge pipe 25 and the supply pipe 24 on a single surface of the body 15. ing. It's a size, discharge pipe 28id,
It is connected to the tank 26 at a position lower than the liquid []B in the tank 26. Therefore, the liquid level A' also exists in the discharge pipe 28 before the pump 27 is started, but even in this case, the same effect as in the case of FIG. 3 can be achieved.

FIG. 6 is a sectional view of an atomizing device showing still another embodiment of the present invention, and the Yoshioka symbols in FIGS. 3 and 5 are corresponding structures.

In the figure, a nozzle plate 17 of a pressurizing chamber 14 with 22 supply ports is shown.
The pump 27 is installed in the center of the tank and is configured to spray upward, and by causing the liquid to flow as shown by the arrow in the figure using the pump 27, air bubbles (not shown) due to cavitation are eliminated. Even with such a configuration, the air can be reliably exhausted from the exhaust port and a stable spraying operation can be maintained.

FIG. 7 is a sectional view of an atomizing device showing another embodiment, and the same reference numerals as in FIG. 3 indicate corresponding structures.

In the same figure, the discharge pipe 25 is at a higher position until the inlet of the pump 27, and the closer it is to the pump 27, the higher the position is. ,! 0: It is configured to be oblique so that cavitation bubbles (not shown) can be discharged more smoothly. Additionally, the liquid level B in the tank 26 is a little higher than the pressurizing chamber 14, and therefore, a liquid level N' exists in the discharge pipe 25 before the pump is started. In this case, if B is set too high above the nozzle 16, the liquid will overflow from the nozzle 16, but as long as the liquid does not overflow from the nozzle due to the effect of the surface tension of the liquid (or if overflow is allowed), configuration can be taken.

Of course, even in such a configuration, when the pump 27 is activated, the pressure inside the pressurizing chamber 14 becomes lower than the outside air pressure at the nozzle 16 due to the pressure loss due to the flow path resistance of the supply pipe 24. This makes it possible to perform stable spraying, and moreover, during the spraying operation, the liquid is completely prevented from overflowing to the outside.

As described above, the present invention can take various embodiments as shown in FIGS. 3 and 5 to 7, and in some cases, for example, in FIG. It will be clear that it is also possible to adopt a configuration in which the outlet of the discharge pipe 28 does not return to the tank 26, and that many further embodiments are possible.

FIG. 8 is a cross-sectional view of a combustion device to which an atomizer according to still another embodiment of the present invention is applied, and the same reference numerals as in FIG. 3 indicate corresponding structures.

In FIG. 8, kerosene is supplied to the tank 26 from a cartridge tank 30 as shown. The tank 26, the atomizing section 13, and the pump 27 are connected to the supply pipe 2 as shown in the figure.
4, a discharge pipe 25 and a discharge pipe 28 are connected to each other, and kerosene is circulated as shown by the arrow in the figure along with the operation of a plunger type electromagnetically driven pump 27. At the same time, the combustion fan 31 is activated to generate an air flow as shown by the arrow in the figure, thereby performing pre-purging. Next, an AC voltage as shown in FIG. 4 a, b, or C is supplied to the piezoelectric vibrator of the atomizing section 13, and atomized particles (atomized droplets) 29 are atomized, and an igniter (not shown) is activated. ignites and burns.

Since many of the air jet ports 32 are distributed above the combustion tube 33, the flame 34 is generated only on the ";" side of the combustion tube 33 as shown in the id diagram, resulting in blue flame combustion.

The atomizing unit 13 is placed in a temperature atmosphere as shown in the figure, and the kerosene in the tank 26 is circulated by a pump 27.
Since the atmospheric temperature of the tank 26 is low and the heat dissipation area is sufficiently larger than the atomization section 13, the atomization section 13 receives a good cooling effect. That is, since the configuration is such that kerosene having a sufficiently low temperature is circulated through the atomization section 13 by the pump 27,
The piezoelectric vibrator, adhesive layer, etc. of the atomization section 13 are maintained at a much lower temperature than the ambient temperature.

Therefore, this #i formation prevents a temperature increase due to heat generation of the piezoelectric vibration r and a decrease in the reliability of the piezoelectric vibrator due to the atomization unit 13 being placed in hot water, and guarantees extremely high reliability. It is possible to realize an atomization device that can.

Effects of the Invention As described in Section 2, according to the present invention, one nozzle is provided in the pressurizing chamber and the atomization is performed by vibrating it with an electric vibrator. By providing an outlet and connecting each to the tank and the liquid transport means, the liquid is sent to the liquid transport means and then filled into the pressurizing chamber. It is possible to realize an atomization device with an extremely compact configuration that can reliably fill a pressurized chamber with liquid regardless of its density, etc., and can atomize liquid extremely stably and with low power consumption. .

Furthermore, it is an object to realize an atomizing device that does not have any inconveniences such as liquid leaking out from the nozzle, discharge pipe, etc. and contaminating the device, or liquid adhering to the outer surface of the nozzle plate and causing an unstable spray state. is possible.

However, since the liquid is sent through a pressurized chamber, it is especially important to prevent the temperature of the electric vibrator from increasing, and to provide a highly reliable atomization device.
In addition to providing stable and reliable atomization even in high-temperature atmospheres! I can guarantee that it was created by Jino.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional atomizing device, FIG. 2 is a piezoelectric ceramic drive voltage waveform diagram of the same atomizing device, FIG. 3 is a sectional view of an atomizing device according to an embodiment of the present invention, and FIG. Figures a, b and C show the spray u1. FIG. 5 is a sectional view of an atomizing device according to another embodiment of the present invention, FIG. 6 is a sectional view of an atomizing device according to another embodiment of the present invention, FIG. 7 is a sectional view of another embodiment of the atomization device;
FIG. 8 is a sectional view of a combustion device to which an atomizing device of yet another embodiment is applied. 14... ・Pressure chamber, 15... Body, 16...
... Nozzle, 19... Electric vibrator, 22...
...Supply port, 23・Discharge port, 26...Tank, 2
7...Liquid feeding means (pump). Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 2.527 Figure 4 Figure 7 Figure 8

Claims (1)

[Claims] (1) A body having a pressurized chamber filled with liquid, a nozzle provided to face the pressurized chamber, and a liquid in the pressurized chamber that is vibrated and sprayed from the nozzle. The pressurized chamber is provided with a supply port and a discharge port, and the supply port and the discharge port are connected to the tank and the liquid. An atomizing device configured to be connected to a transporting means and to fill the pressurized chamber with a liquid. (2) The atomizing device according to claim 1, wherein the amount of liquid sent by the liquid sending means is larger than the amount of spray sprayed from the nozzle. (3) The atomizing device according to claim 1 or 2, wherein the liquid feeding means is an electric pump. (4) Claim 1 (5) wherein the discharge side of the liquid feeding means is connected to the tank to circulate the liquid.
5. The atomizer according to claim 4, wherein the amount of heat dissipated from the tank is larger than the amount of heat dissipated from the body, and the amount of heat dissipated from the body is removed by circulation of the liquid. (6) The means of inspection is equivalent to or greater than the above-mentioned pressurized chamber.”