JPS6029311B2 - atomization device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an atomization device used for humidifying air, atomizing medical liquids, or gasifying liquid fuel such as kerosene.

Its first objective is to provide an atomization device of simple and compact construction.

The second purpose is to realize an atomizer that can obtain atomized particles with a small particle size, and when used in a liquid fuel combustion device, the liquid fuel is almost directly gasified and ignited instantaneously. The purpose of this is to create a combustion device that is capable of The third object is to provide an atomization device that allows for extremely easy adjustment of the amount of atomization over a wide range.

Conventional liquid atomization devices include those that drip liquid onto a rotating body and shake it off using centrifugal force to atomize it, and those that apply pressure to the liquid using a high-pressure pump and spray it from a nozzle to atomize it. Various methods have been proposed and put into practical use, such as those in which liquid is dropped onto an ultrasonic vibrator and atomized by ultrasonic vibration. However, these secondary atomizing devices have complicated or large structures, and are therefore expensive.

In addition, even if the size of the atomized particles is small, it is several tens of meters to 1
It was about 00r. Therefore, when used in a liquid fuel combustor, the combustion performance is poor, and soot, C○, and N
○× etc. were likely to occur. Therefore, a large-scale vaporization device is required, and at the start of combustion, it is necessary to wait several minutes until the temperature of the vaporization section rises sufficiently. In addition, it is difficult to adjust the amount of atomization over a wide range as the amount becomes smaller, and there are many disadvantages in terms of amount stability, particle size, etc.
Especially in the case of combustion equipment, combustion tends to become unstable.
The present invention eliminates these drawbacks.

FIG. 1 is an embodiment in which the present invention is applied to a liquid fuel combustion device, and is a slow-growing sectional view of a combustion device for burning kerosene, light oil, etc.

In the figure, 1 is a case, and combustion air is introduced through air holes 3 by a fan 2.

4 is a damper, which adjusts the amount of combustion air.

Reference numeral 5 denotes a support column, by which the base body 6 is supported.

A pressurizing chamber 7 is formed inside the base body 6, and the pressurizing chamber 7 has a horn shape (exponential horn).
Further, at its tip, there is a closed part 8 having a constant cross-sectional area in all directions of the axis, and this opening □ part 8 is closed by a nozzle part 9.
A nozzle hole 10 is provided in the center. A diaphragm 11 that closes the pressurized chamber 7 is provided at the bottom of the pressurized chamber 7, and is fixed to the base body 6 by a cylindrical support section 12. Electrode plates 13 and 14 and piezoelectric vibrators 15 and 16 are fixed to the diaphragm 11 to constitute an electric vibrator. The two piezo vibrators 15 and 16 are electrically connected in parallel. Note that the electric vibrator may be a magnetostrictive vibrator. Reference numeral 17 denotes a PTC heater, which is attached to the outer periphery of the base 6.

This is to keep the temperature of the kerosene, which is the liquid introduced into the pressurizing chamber 7, constant and to prevent changes in the viscosity of the kerosene, and has an insulating structure from the base body 6. 18 is a guide support, and an air guide 19 is provided at the tip.

A burner stand 20 supports a burner 21, forms a mixing chamber 22 for mixing air and atomized particles, and has a stirring blade 23.
has been established.

The burner 21 and the base 6 are electrically connected to the same potential, and a DC power supply 2 is used so that a high voltage is applied between the burner 21 and the base 6.
4 are connected. This is to charge the atomized particles and to promote the atomization of the kerosene by the electric attraction action. In other words, it not only promotes atomization through electrostatic action, but also slightly charges the atomized particles.
This reduces particle recombination and adhesion to the burner 21, burner stand 22, and stirring blade 23. In addition, 2
5 and 26 are insulating materials, which are used to maintain the potential relationship of each part by the DC power supply 24.

27 is a tank, and 29 is a cartridge tank, which are horizontally arranged so that the liquid level 30 of kerosene is slightly lower than the nozzle 10.

Reference numeral 31 denotes a filter, and the kerosene from which dust has been removed by the filter 31 is supplied through a liquid supply port 33 provided at the bottom of the base 6 through a connecting pipe 32.

34 is a pressure introduction pipe, which increases the pressure in the tank 27 by the wind pressure generated by driving the fan 2, and completely fills the horn-shaped pressurizing chamber 7 in the base body 6 with kerosene. , for making the pressure inside the nozzle 10 positive with respect to atmospheric pressure.

The operation of the combustion device configured as above will be explained.

First, when the fan 2 is driven, air is supplied from the air hole 3 in an amount determined by the damper 4 and flows in the direction of the burner 21 as indicated by the arrow in the figure. Therefore, as described above, the pressure in the tank 27 increases, the pressurizing chamber 7 is completely filled with kerosene, and the pressure on the pressurizing chamber 7 side of the nozzle 10 becomes positive with respect to atmospheric pressure. Although the pressurizing chamber 7 is oriented horizontally in the figure, in order to completely remove the air within the pressurizing chamber 17, it is preferable that the pressurizing chamber 7 be oriented vertically as in the embodiment shown in FIG. At the same time, the stirring blade 23 rotates. Reference numeral 35 denotes a control device, which includes a combustion control section 36, a vibrator drive section 37, and the like.

The oscillator driving section 37 supplies alternating power as shown in FIG. 6 to the puezo oscillators 15 and 16 in response to a command from the combustion control section 36.

This alternating power causes the piezoelectric vibrators 15 and 16 to
2 as a fulcrum, it vibrates toward the center of the pressurizing chamber 7. When the piezo vibrators 15 and 16 bend in the direction of the nozzle 10, the pressure inside the pressurizing chamber 7 increases, and because of the horn shape, the pressure increases toward the tip, and becomes extremely large near the nozzle 10. . Therefore, kerosene is discharged from the nozzle 10. The nozzle 10 has a shape as shown in FIGS. 3a, b or c, d. That is, the nozzle hole 101
A notched recess 36 or 38a, 38b is provided, and the axial cross section of the nozzle hole 10 is non-uniform in the nozzle circumferential direction. As a result, as shown by the arrow in FIG. 3, the kerosene discharged from the nozzle hole 10 is given some rotational movement in front of the nozzle hole 10, and when it is discharged, the kerosene is discharged in a radial discharge direction.

Therefore, the particle size of the particles discharged from the nozzle hole 10 is much smaller than the nozzle hole diameter (about 200 mm).
It will be from several skins to more than 10 rm). Next, Epizo oscillator 15
, 16 is bent to the side opposite to the nozzle hole 10, it acts like a so-called fluid diode due to the effect of the opening 8 provided at the tip with a constant cross-sectional area in all directions of the axis, and therefore,
The pressure inside the pressurizing chamber 7 becomes quite low.

Therefore, kerosene is sucked into the pressurizing chamber 7 from the connecting pipe 32 through the liquid supply port 33. That is, kerosene is discharged from the nozzle hole 10 and supplied from the tank 27 by one reciprocating operation of the piezo vibrators 15 and 16. Therefore, no special coupling equipment for supplying kerosene is required. The alternating power is 10
Since the high frequency power is about ~30KHZ, the kerosene is discharged while undergoing ultrasonic vibrations, and the nozzle hole 10
Coupled with the effect of the nozzle hole shape mentioned above, the particle size of the particles emitted from the nozzle becomes extremely small, and can be as small as several micrometers.

Further, due to the electrostatic field effect of the DC power source 24, the particles are further atomized and charged, and are prevented from recombining with each other and increasing the particle size.

Mixing of the atomized particles with air is promoted by the stirring blade 23, and the atomized particles are supplied to the burner 21 in the state of a child mixed gas.

Then, it is ignited by an ignition means (not shown) and combusts. A flame rod 39 detects the ionic current in the flame and sends the signal to the combustion control device 36.

The flame rod 39 is for detecting the combustion state of the flame, and may be a means for detecting the light or temperature of the flame. The combustion control device 36 gives a command to the oscillator drive unit 37 by the signal from the frame rod 39, and when there is too much fuel, the average power of the alternating power given to the piezo oscillators 15 and 16 is set as shown in Fig. 6 a to c. Conversely, when there is too little fuel, the average power is increased to keep the air-fuel ratio constant.

The shaft 4a of the damper 4 is linked to a variable resistor 40 connected to the combustion control device 36, and the average of the alternating power to the piezo oscillators 15 and 16 is controlled according to the damper 4's function, that is, the amount of air. It changes the value. That is, the air-fuel ratio target value corresponding to the air amount determined by the damper 4 is determined by the variable resistor 40, and the air-fuel ratio target value is determined by the variable resistor 40, and
The signal from the frame rod 39 prevents disturbances in the air-fuel ratio due to changes in kerosene viscosity, calorific value, etc. Actually, depending on the signal of the variable resistor 40, as necessary,
The combustion control device 36 operates by changing the control target value of the ion current by the flame rod 39 so as to achieve the optimum air/fuel ratio according to the combustion amount level. FIG. 2 is a sectional view of the configuration of a warm air heater showing another embodiment of the present invention, and the same reference numerals as in FIG. 1 correspond to the same parts.

In the figure, reference numeral 41 denotes a hot air fan case, in which indoor air is sucked in through a suction port 43 by a convection fan 42, heat exchanged in a combustion tube heat exchanger 44, and hot air is blown out from an air outlet 45.

Combustion air is sent to the burner 21 by the combustion fan 2 through the air guide 19, but a heater 46 is provided along the way, and here, at the start of combustion, it improves the ignitability of the atomized particles and improves the combustion performance (more The purpose is to improve combustion performance by making fine particles (ie, complete gasification) and to generate child heat from the burner 21.

After the ignition, the heat of the flame F achieves the above purpose, so the power supply to the heater 46 is stopped. A liquid supply port 33 is provided at the bottom of the horn-shaped pressurization chamber 7. By providing the liquid supply port 33 at the bottom, the air in the pressurization chamber 7 is completely expelled and the pressurization chamber 7 is It can be a hermetically sealed chamber filled with kerosene. This is a necessary condition for such an atomization device, and if even a small amount of air enters the pressurized chamber 7.
This is because if the particles remain in the water, normal atomization will not be possible. In addition, the connecting pipe 32 is connected as shown in the figure, and the liquid supply port 33 is configured to be at a higher position than the outlet 47 of the tank 27, so that, as described above, air may be mixed in and normal mist may occur. This prevents the development of

The filter 31 is installed in a constriction 48 provided in the middle of the tank 27 in order to prevent dust from clogging due to the small nozzle hole 10.

Is the liquid level 30 of the tank 27 the same as the nozzle hole 10?
The head difference is such that when the piezo vibrators 15 and 16 are stopped, the surface tension of the light oil prevents it from overflowing from the nozzle hole 10. If there is a possibility that the surface force is broken due to vibration or the like and kerosene overflows from the drain hole 10, a configuration that utilizes the wind pressure generated by the operation of the fan 2, as in the embodiment shown in FIG. 1, should be adopted. , when the fan is stopped, the nozzle hole 10 is at the liquid level 30.
The pressure of the kerosene inside the nozzle hole 10 may be set to be lower than atmospheric pressure.

Reference numeral 17' denotes a PTC heater, which is installed in the middle of the connecting pipe 32 and raises the temperature of the kerosene to a predetermined value and keeps it at a constant value.

Note that 49 is a speed changeover switch for the fan 42, which moves with the damper 4.

50' is an AC power supply.

As described above, as shown in the embodiments shown in FIGS. 1 and 2, it is possible to supply and discharge liquid with an extremely simple configuration and by simply supplying alternating power to the piezo vibrators 15 and 16. Moreover, it is possible to realize the formation of extremely fine liquid particles that are close to gaseous state.

FIG. 4 shows a more detailed embodiment of the control device 35 in FIGS. 1 and 2, and the same reference numerals as in FIGS. 1 and 2 are equivalent.

In the figure, 51 is a power transformer, and diodes 52 and 53 and capacitors 54 and 55 form a power supply section of the vibrator drive circuit.

56 is an oscillator, which is a sine wave oscillator such as a CR oscillator.

The output of the oscillator 56 is supplied to a multiplier 58 via a switch means 57.
is configured such that the output thereof is supplied to piezoelectric vibrators 15 and 16.

The switch means 57 is controlled by the duty control section 59.
Opening and closing are controlled in synchronization with the oscillator 56 so that a voltage having a waveform as shown in FIG. 6 is applied to the piezo vibrators 15 and 16. The opening/closing duty of the switch means 57 by the duty control section 59 is determined by a command from the combustion control section 36, and the average power supplied to the piezo vibrators 15 and 16 is controlled by duney control. That is, the combustion control section 36 detects the direct current flowing from the flame rod 39 to the burner 21 using a resistor 60 and a capacitor 61, and controls the duty control section 59 so that the current reaches the set current value determined by the variable resistor 40. It gives instructions.

For example, when the detected ion current is too large, the piezo vibrator 15, 16 can be
The combustion control device 36 operates to reduce the number of vibrations per unit time and reduce the amount of atomization. Therefore, the amount of fuel supplied decreases, the ion current decreases and is controlled to the set value, and the air-fuel ratio is maintained at a constant value. Although the duty control section 59 performs duty control using one cycle as the minimum unit as shown in FIG. 6, it is clear that the minimum unit may be multiple cycles.
Further, 62 is a diode, and 63 is a capacitor.

With the above circuit configuration, the piezo oscillators 15 and 16 can always be supplied with the sinusoidal waveform power generated by the oscillator 56 in a constant waveform regardless of the duty, so the operation of the oscillators is stable. Moreover, it is extremely advantageous in terms of life, etc., and can completely prevent the occurrence of cavitation due to spurious gas, and can exhibit excellent performance as an atomizing device. FIG. 5 shows another embodiment of the control device 35, and the same reference numerals as in FIG. 4 are equivalent.

Inductors 64, 65, capacitor 66, thyristor 6
7. The diode 68 constitutes a so-called series inverter, and the output transformer 69 supplies the inverter output to the piezo vibrators 15 and 16.

Since the output transformer 69 converts the inverter current into a voltage and supplies it to the piezo oscillators 15 and 16, the piezo oscillator 15 generates a voltage waveform close to a sine wave as shown in FIGS. , 16. That is, resistor 70,
Resistors 73 to 76, a capacitor 77, and a programmer full union transistor (PUT) connected to a DC power supply consisting of a Zena diode 71 and a capacitor 72.
When the trigger frequency of the syringe 67 is changed according to the oscillation frequency of the relaxation oscillator circuit consisting of 78,
As shown in ~c, the repetition period and magnitude of the current in the inverter change, and accordingly, the repetition period and magnitude of the sinusoidal voltage supplied to the vibrators 15 and 16 also change at the same time.

As described above, the combustion control unit 36 controls the current flowing to the input light emitting diode of the photocoupler 79 based on the ion current signal obtained from the flame rod 39, and as a result,
The operating current of the output transistor of the photocoupler 79 is controlled. Therefore, the oscillation frequency of the oscillation circuit made up of the PUT 78 and the like changes, and the vibration period and the period of vibration of the piezoelectric vibrators 15 and 16 are simultaneously controlled. In this way, by using a series inverter in the vibrator drive unit and supplying the inverter resonance current to the piezo vibrators 15 and 16 via the output transformer 69, the duty and vibration of the sinusoidal voltage can be controlled. At the same time, it can be easily controlled by simply changing the operating frequency of the inverter. Figure 8 shows the piezo oscillator 15
, 16 are other implementation waveforms showing the method for controlling the average power applied.

That is, as shown in FIG. 4, if the oscillator 56 and the multiplier 58 are used, the switch means 57 is removed, and the output voltage of the oscillator 56 or the multiplier degree of the multiplier 58 is controlled, the eighth It is possible to realize average power control (control during shaking) as shown in the figure. FIGS. 9a to 9c are graphs showing changes in the amount of atomization q according to the average power control method supplied to the three types of vibrators described above.

That is, a is when the duty D is controlled as shown in Fig. 6, and b is when the frequency na (that is, the duty D) and the oscillation (voltage) are changed simultaneously as shown in Fig. 7. c indicates the atomization amount change q during vibration, that is, when the voltage V is changed.

As described above, according to the atomization device of the present invention, a pressurized chamber is filled with liquid, vibrated by an electric vibrator, and atomized by being discharged from a nozzle hole provided facing the pressurizing chamber. Since the liquid is filled and supplied into the pressurized chamber through the liquid supply port, the functions of suction, discharge and atomization of the liquid can be realized with an extremely simple structure.
The atomized particles can be made very small, and the amount of atomization can be freely adjusted over a wide range.

Therefore, it is possible to provide an atomizing device that has excellent atomizing characteristics, has a simple configuration, is compact, and is inexpensive, and its industrial value is extremely large. In addition, as in the example, by making the nozzle into a plate shape and providing the nozzle hole, the nozzle hole can be processed very easily and with little variation, and the length of the nozzle hole is 4 mm. Therefore, it can be difficult for garbage to become clogged.

Furthermore, if the pressurizing chamber has a circular cross section and the electric vibrator has a circular outer periphery, and the centers thereof are arranged on the same axis as in the embodiment, the discharge efficiency can be improved. Discharge operation can be stabilized. moreover,
If the center of the nozzle is also arranged on the axis, further improvement in ejection efficiency and stability of ejection operation can be obtained. Furthermore, if the cross-sectional shape of the nozzle in the discharge direction is made non-uniform in the circumferential direction, the particle size of the atomized particles can be made even smaller. By configuring the cylindrical support section parallel to the curved direction of the diaphragm, the efficiency of the oscillator can be maintained extremely well.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a structure showing one embodiment of the present invention, FIG. 2 is a cross-sectional view of a structure showing another embodiment of the present invention, FIGS. 3 a to d are views showing the structure of a nozzle, and FIG. 5 is a circuit diagram showing another embodiment of the control device, FIGS. 6 a to c are driving waveform diagrams of the vibrator, and FIGS. FIGS. 8a and 8b are drive waveform diagrams of the vibrator, and FIGS. 9a to 9c are explanatory diagrams showing a method of controlling the amount of atomization. 7... Pressure chamber, 6... Base, 8... Opening, 9...
... Nozzle, 10... Nozzle hole, 11... Working plate, 12.
... Support part, 15, 16... Piezo vibrator (electric vibrator), 33... Liquid supply port, 38, 38a, 38b...
- Concavity (uneven cross-sectional shape). Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 9

Claims (1)

[Scope of Claims] 1. A base body having a pressurizing chamber filled with liquid, a nozzle hole provided to face the pressurizing chamber, an electric vibrator for vibrating the liquid in the pressurizing chamber, and the An atomization device comprising: a liquid supply port for supplying liquid to the pressurizing chamber. 2. The atomization device according to claim 1, wherein the nozzle hole is provided in a plate-shaped nozzle, and the nozzle is configured to face the pressurizing chamber. 3 The pressurizing chamber has a circular cross section, and the electric vibrator has a circular outer periphery, and the center of the circular cross section of the pressurizing chamber and the center of the circular electric vibrator are approximately the same. 2. The atomizing device according to claim 1, wherein the atomizing device is configured to be on an axis. 4. The atomization device according to claim 3, wherein the pressurizing chamber is formed into a horn shape. 5. The atomization device according to claim 3, wherein the electric vibrator is attached to the base by a cylindrical support part parallel to the axial direction of the pressurizing chamber. 6. The atomization device according to claim 1, wherein a recess is formed in a part of the nozzle hole. 7. The electric vibrator according to claim 3, characterized in that the center of the electric vibrator having a circular outer periphery and the center of the surface of the nozzle facing the pressurizing chamber are coaxial. Atomization device.