JPS62136263A - Ultrasonic atomizing apparatus - Google Patents

Abstract

PURPOSE:To stably perform fine pulverization by efficiently supplying a liquid to the edge part of a vibrator, by inclining a wall surface forming the outlet part of the nozzle orifice of a liquid supply means from the surface vertical to the axis of the vibrator. CONSTITUTION:A wall surface 8a forming the outlet part 40 of the nozzle orifice 36 of a liquid supply means 8 is inclined by a predetermined angle thetafrom the vertical surface with respect to the axis of a vibrator 10. That is, the wall surface 8a is brought to a conical inclined flat surface and the angle thetaof inclination thereof is set to 10-60 deg.. By this constitution, the flow A of air flowing around an atomizing apparatus comes to flow along the wall surface 8a and no vortex stream is generated. Therefore, the jet stream C of the liquid from the nozzle orifice 36 is not largely affected by external force and reaches the predetermined position of the edge part 26 of the vibrator 10 as designed and the effective fine pulverization of the liquid is achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally relates to an ultrasonic atomizer, and more particularly to (1) an automotive fuel injection device 1 such as an electronically controlled gasoline injection valve or an electronically controlled diesel injection valve; Fuel nozzle for turbines.

(3) Industrial, commercial, and domestic boilers, heating furnaces,
Burners for heaters, (4) Industrial liquid sprayers, such as drying sprayers for drying liquid materials such as foods, pharmaceuticals, agricultural chemicals, and fertilizers, temperature control and humidity control sprays, and baked powder sprayers (ceramic grains), spray A coating device, reaction accelerator, and (5
) The present invention relates to an ultrasonic atomization device which is suitably used in non-industrial liquid spray devices, such as pesticide sprayers, disinfectant sprayers, etc., and which atomizes liquid intermittently or continuously.

Traditionally, in the various fields mentioned above, liquids (
The term "liquid" is used to include not only liquids but also liquid substances such as suspension solutions. Pressure atomizing burners or liquid atomizers are used to atomize or atomize the The atomizing device used in such a spray burner or liquid atomizer atomizes the liquid by a shearing action between the liquid injected from the nozzle and the outside air (atmosphere). Therefore, in order to atomize the supplied liquid, it is necessary to increase the liquid supply pressure.
Liquid supply equipment such as pumps and piping has become complicated and large.

Furthermore, adjusting the injection flow rate can be done by changing the pressure of the supply liquid or
This is done by changing the area of the injection port of the nozzle, but with the former method, the state of atomization worsens at low flow rates (low pressures), and as a countermeasure for this, 1. In large boilers, air or steam is used in combination to atomize the supplied liquid fuel. As a result, devices have become increasingly complex and large. on the other hand.

In the latter method, the structure of the nozzle becomes extremely complicated, and its adjustment and maintenance are difficult.

In order to improve these shortcomings of conventional atomizing devices, attempts have been made to apply pressure to the injection port of the atomizing device to spray the liquid and at the same time apply ultrasonic vibrations to the liquid.

I will do it. However, conventional liquid atomization devices using ultrasonic waves have extremely small amounts of atomization, and cannot be used in the above-mentioned atomization devices that require a large amount of atomization.

In order to solve the above-mentioned conventional problems and achieve atomization of a large volume of liquid, the present applicant provided an edge part at the end of the ultrasonic transducer and supplied liquid to the edge part in the form of a thin film. An ultrasonic jetting method and a jetting nozzle in which a large amount of liquid is atomized from the edge portion have been proposed (Japanese Patent Application No. 1987-
77572).

The injection nozzle, ie, the atomization device, will be briefly described with reference to FIG. 4. The atomization device, ie.

For example, a fuel nozzle 1 for a gas turbine has a central hole 2 in the center.
The valve box 4 has an elongated, generally cylindrical shape. A liquid supply means, ie, a fuel supply means 8, in which a through hole 6 coaxially aligned with the center hole 2 of the valve body 4 is formed, is connected to one end of the valve body 4 by means of a retainer (not shown) or by a retainer (not shown). 4 and is provided integrally.

A vibrator 10 is disposed passing through the center hole 2 of the valve box 4 and the through hole 6 of the fuel supply means 8. The vibrator 10 has a main body part 14, a transducer shaft part 16 in the shape of an elongated column having a smaller diameter than the main body part 14, and a transition part 18 connecting the main body part 14 and the shaft part 16. Tsuba 20 with a large diameter
The collar 20 includes a shoulder portion 22 formed at the other end of the valve box 4, and an annular vibrator retainer 24 attached to the end surface of the valve box 4 by bolts (not shown). It is attached to the valve box 4 by.

The shaft portion 16 of the vibrator 10 further protrudes outward from the valve box 4 and the liquid supply means 8. An edge portion 26 is formed at the tip of the vibrator 10, that is, the tip of the shaft portion 16.

According to FIG. 4, the edge portion 26 of the vibrator 10 has a shape having a plurality of chevron-shaped protrusions with the same diameter, but it can also be shaped into an annular step shape with two or more steps whose diameter is gradually reduced. It is also possible to have a shape in which the diameter gradually increases, or the diameter gradually decreases and then increases.

The fuel supply means 8 includes the edge portion 2 of the vibrator 10.
One or more supply passages 28 for supplying fuel to the fuel cell 6 are arranged in an annular manner. A fuel supply port 30 of the supply passage 28 opens approximately adjacent to the upper end of the edge portion 26, and the other end 32 of the supply passage 28 is connected to a fuel supply source (not shown).
connected to.

Liquid fuel is supplied.

In the above configuration, the vibrator 10 is continuously vibrated by the ultrasonic vibration generating means 100 operatively connected to the main body portion 14 . Therefore, when the liquid fuel is supplied to the edge portion 26 via the supply passage 28, the liquid fuel is atomized and injected outward.

The inventors of the present invention further conducted research to achieve atomization of a large volume of liquid in the atomization device described above, and as a result, as shown in FIG. or a liquid supply passage 36 instead of the supply passage 28
It has been found that it is extremely efficient to provide a liquid and directly inject and supply the liquid from the supply passage 36 to the edge portion 26 of the vibrator. Further, the supply passage 36 is formed at a predetermined angle (
α) 1 For example, the wall surface 8a forming the outlet of the supply passage 36, that is, the outlet portion of the liquid supply passage 36 of the liquid supply means 8, is formed perpendicular to the vibrator axis. It was done.

Further, as understood from FIG. 5, the supply passages 36 are provided at four locations or on two or more arbitrary sides.

Generally, an atomizing device having such a configuration can efficiently atomize a large volume of liquid as described above, but it is also possible to use the atomizing device in, for example, an automobile fuel injection device or a fuel nozzle for a gas turbine. In use, there is an air flow A flowing axially around the outer circumference of the atomizer, as illustrated in FIG.

The air flow A generates a vortex B at the protruding portion of the liquid supply passage 36, and the liquid jet flow C from the liquid supply passage 36 is greatly echoed.
The liquid does not reach a predetermined position, and as a result, effective atomization of the liquid cannot be achieved. Such disadvantages were particularly significant when the amount of supplied liquid was small. Furthermore, the once atomized liquid particles collide with and adhere to the wall surface 8a forming the outlet portion of the liquid supply passage 36 due to the vortex flow B, causing liquid dripping.

The present invention relates to an improvement of such an atomizing device.

An object of the present invention is to provide an ultrasonic atomizer that can supply liquid continuously or intermittently.

Another object of the present invention is to provide an ultrasonic atomizer that can efficiently atomize large and small volumes of liquid, and therefore can have a very large turndown ratio.

Another object of the present invention is to provide an ultrasonic atomization device that can achieve stable atomization in which the state of atomization (flow rate, particle size) does not vary depending on the properties of the supplied liquid, particularly the viscosity.

. The above objectives are achieved by the ultrasonic atomization device according to the present invention. In summary, the present invention comprises ultrasonic vibration generating means;
an elongated vibrator connected at one end to the ultrasonic vibration generating means and having an edge section at the other end; and for supplying liquid to the edge section.

a liquid supply means provided close to the end of the vibrator on the side having the edge portion, and the liquid supply means includes an ultrasonic mist having a nozzle hole for directly injecting liquid to the edge portion. The ultrasonic atomizer is characterized in that the wall surface forming the exit portion of the nozzle hole of the liquid supply means is formed to be inclined from a plane perpendicular to the vibrator axis. According to a preferred embodiment of the present invention, the wall surface forming the outlet portion of the nozzle hole of the liquid supply means is a conical inclined plane! The inclination angle (θ) is 10'' to 60', or the wall surface forming the exit portion of the nozzle hole of the liquid supply means is a convex groove curved surface.

Next, the ultrasonic atomization device according to the present invention will be explained in detail with reference to the drawings.

The present invention can be suitably used in various applications as described above, but in this embodiment, it is used for the gas turbine fuel nozzle described in relation to FIG.
In the figures and FIG. 3, only the tip of the atomizer is shown.

Referring to FIG. 1, the atomization device according to the present invention, that is, the fuel nozzle 1 for a gas turbine in this embodiment, has a liquid supply means 8 connected to a liquid supply passage.

A nozzle hole 36 is provided outside the nozzle hole 28 or in place of the nozzle hole 28, and liquid is directly injected and supplied from the nozzle hole 36 to the edge portion 26 of the vibrator.

According to the invention, the wall surface 8a forming the outlet portion 40 of the nozzle hole 36 of the liquid supply means 8 is inclined by a predetermined angle (θ) from a plane perpendicular to the vibrator axis. In other words, the wall surface 8a is a conical inclined plane, and its inclination angle is (0).
is 10° to 60″.

With such a configuration, as shown in the figure, the air flow A flowing around the atomization bag H becomes a flow along the wall surface 8a, and the air flow A flowing around the atomization bag H becomes a flow along the wall surface 8a. figure)
is not generated, and therefore the liquid jet flow C from the nozzle hole 36
is not significantly affected by external forces, and the liquid jet flow C reaches the predetermined position of the vibrator edge portion 26 as designed, and effective atomization of the liquid is achieved. Further, according to the above structure according to the present invention, it is possible to avoid spray droplets from adhering to the wall surface 8a and its vicinity, coating the wall surface or causing liquid dripping, which would cause various problems.

According to the embodiment shown in FIG. 2, the outer peripheral portion 8b of the wall surface 8a
is further inclined from the wall surface 8a, and the inclination angle (θ2)
is 10° to 50°. In the wooden embodiment, numerically showing a preferred embodiment, the outer diameter of the liquid supply means 8 is 3.
In the case of 2 mm, in the range of 1 dimension W=15, the spray angle of the nozzle is 200 for α1 and 26° for α2, and the angle of the wall surface is 35° for θ1 and 35° for 0.

Furthermore, in order to smooth the air flow A around the outer periphery of the atomizer, the wall surface 8a forming the exit portion of the nozzle hole may be formed into a convex groove curved surface, as shown in FIG. The radius of curvature R of the convex groove curved surface 8a is preferably 12 to 40 m.
Of course, it is also possible to form it from a plurality of curved surfaces.

According to FIG. 1, the edge portion 26 of the vibrator 10 has a shape having a plurality of chevron-shaped protrusions with the same diameter, but it can also be shaped into an annular step shape with two or more steps whose diameter is gradually reduced. It is also possible to have a shape in which the diameter increases gradually, or the diameter gradually decreases and then increases. What is important is that an edge is formed at the tip of the vibrator.

According to the atomizer according to the present invention configured as described above, the vibrator can be stably positioned at a predetermined position not only when the amount of liquid supplied is large, but also when the flow rate is low, regardless of the properties of the liquid. The advantage is that the liquid can be atomized and the turndown ratio can be very large.

[Brief explanation of drawings]

1, 2, and 3 are partial cross-sectional views of an ultrasonic atomization device according to the present invention. FIG. 4 is a sectional view of a conventional ultrasonic atomization device. FIG. 5 is a front view of the apparatus of FIG. 4. 6 is a partially enlarged sectional view of the apparatus of FIG. 5; FIG. 1:'s conversion device 4: Valve box 8: Liquid supply means 8a, 8b = Nozzle outlet forming wall surface 10: Vibrator 26: Edge portion 36: Liquid supply passage (nozzle hole) 40: Nozzle hole outlet Σ

Claims (1)

[Claims] 1) An ultrasonic vibration generating means, an elongated vibrator connected at one end to the ultrasonic vibration generating means and having an edge portion at the other end, and supplying liquid to the edge portion. In order to achieve this, the vibrator is provided with a liquid supply means provided close to the edge portion of the vibrator, and the liquid supply means has a nozzle hole for directly injecting liquid to the edge portion. An ultrasonic atomizer, characterized in that a wall surface forming an exit portion of the nozzle hole of the liquid supply means is formed to be inclined from a plane perpendicular to the vibrator axis. 2) The wall surface forming the exit portion of the nozzle hole of the liquid supply means is a conical inclined plane, and its inclination angle (θ) is 10
2. The device of claim 1, wherein the angle is between 60[deg.] and 60[deg.]. 3) The device according to claim 1, wherein the wall surface forming the outlet portion of the nozzle hole of the liquid supply means is a convex groove curved surface.