JPS5843262A - Atomizing method for liquid to uniform size and device for embodiment thereof - Google Patents

Abstract

PURPOSE:To generate a large amt. of micro liquid droplet groups having uniform sizes by punching microhole groups of uniform sizes in a structural body by laser working techniques or the like, supplying the pressurized liquid into said punched hole groups and applying high frequency oscillations of ultrasonic waves to the liquid column groups generated by the punched hole groups. CONSTITUTION:A large number of uniform microholes are punched to a thin sheet 1 of stainless steel or the like by a laser beam working or electron beam working method, and the sheet 1 is mounted airtightly by means of an O-ring 3 or welding into an outflow port 2 for liquid. When pressurized liquid is fed into the port through a liquid feed port (a), the liquid flows out through the microholes of the sheet 1 in the form of a large number of micro-sized liquid columns. High frequency oscillations are applied to a device 4 in the direction (b) parallel or the direction (c) vertical to these liquid column groups, whereby a large amt. of the micro liquid droplet groups 12 of uniform sizes are generated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention utilizes laser processing technology and electron beam processing technology to drill a group of uniform diameter micro holes in a structure, and supplies a pressurized liquid to the drilled holes. A method and apparatus for generating a group of liquid columns with a uniform minute diameter, applying ultrasonic high-frequency vibration to the group of liquid columns, and generating a group of minute droplets with a uniform diameter. It further relates to the use of the atomization method in a gas atmosphere and in a liquid, and to the generation of uniformly sized solid particles by spray drying a solution containing a solvent.

Now, if we consider liquid atomization methods from the viewpoint of industrial needs, the production of large quantities of homogeneous particles will improve the vaporization efficiency of spray equipment, the combustion efficiency of liquid fuel burners, and the associated miniaturization of equipment. It has great industrial significance, such as homogenization of products such as oxidation, atomization of uniform diameters in different liquids, generation of uniform solid particle groups by spray drying, and miniaturization of equipment.

By the way, various conventional atomization methods have been implemented, such as a two-fluid nozzle using gas or liquid flow. One of the methods is to apply ultrasonic high-frequency vibrations. Now, considering the atomization method from the viewpoint of generating a large amount of small droplets evenly, it is possible to generate a large amount with a two-fluid nozzle, but the droplet size is relatively large, and the particle size may be small. There is a drawback that droplets with a uniform diameter cannot be obtained. On the other hand, the method of applying ultrasonic high-frequency vibrations has advantages over the two-fluid method, such as being able to obtain particles with minute diameters and easily controlling the atomization characteristics by adjusting the applied vibrations. Because it is difficult to generate, it is not suitable for industrial production in large quantities and has not been used.

However, in recent years, laser processing technology, electronic bee droplets:
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Advances in precision machining technology, such as micro-machining technology, have made it possible to drill micro holes ranging from several hundred micrometers to several micrometers. Furthermore, position control using laser technology or the like has become possible, making it possible to form a large number of microhole groups in a microscopic area.

The present invention utilizes the above-mentioned advanced technology developed in recent years to automatically drill a large number of uniform diameter micropores, generate a large number of uniform diameter microscopic liquid flow columns, and generate a large number of uniform diameter microscopic liquid flow columns. This is a method of generating a large amount of homogeneous small droplet groups by applying high frequency vibration to the group.

Specific examples will be shown below according to the attached drawings.

In FIG. 1, reference numeral 1 indicates a thin circular plate made of stainless steel, ceramic, etc., in which a large number of microscopic holes are drilled by laser processing technology. This thin plate 1 is airtightly installed at the liquid outlet 2 by 01J ring 3 or by welding. When a slightly pressurized liquid is sent from the liquid inlet a, if high frequency vibration is not applied, thin plate 1
The liquid flows out from the micropores in the form of numerous microscopic liquid columns. When a high frequency vibration volume is applied to the apparatus 4 in the flat direction or in the vertical direction C to these liquid columns, a large number of minute droplets 12 of uniform diameter are generated.

FIG. 2 shows an example of the present invention similar to FIG. 1, and is capable of generating a large number of uniform micro droplets 12 compared to the device shown in FIG. You can drill more holes with the drilled one. The direction of vibration is appropriately axial.

The high frequency application device amplifies the signal from the oscillator 6 using the amplifier 7, and then applies it to the magnetostrictive/electrostrictive element 8, converting the electrical signal into mechanical vibration and applying vibration to the liquid column group. On the other hand, the liquid is pressurized by a pump etc. 11, and then the filter 10
After that, it is supplied to the generating section.
.

Examples will be further described. Thickness 0.2 mm and 0
．． A large number of holes with a uniform diameter of about 30 μm were punched in a 1 mm stainless steel thin disk using a YAG laser with a pinch of 0.2 mm. After this stainless steel thin disk was attached to the device shown in FIG. 1, the device shown in FIG. 3 was connected. Liquids were fed into the apparatus of FIG. 1 through a 1 μm filter at a gauge pressure ranging from about 0.5 to 2 atmospheres. The applied ultrasound was performed at 201<Hz to 70kHz. The generated average
The size of the droplet group was approximately 60 μm. Furthermore, the size of the homogeneous droplets generated could be changed from approximately 10 μm to 60 μm''11 by mixing volatile liquids such as alcohol. By dissolving it in a solution, spraying it, and drying it, it was possible to generate solid particles of uniform diameter.

[Brief explanation of drawings]

FIGS. 1 and 2 show the main parts of a uniform droplet generator in which micropores are drilled. FIG. 3 shows an electric device and a liquid supply device for applying high frequency vibration.

Claims (5)

[Claims] (1) A large number of uniform microholes are drilled into a container-like structure using a laser beam processing method, an electron beam processing method, etc., and the liquid is flowed out through the microholes to form a uniform micro-liquid column group. A method for atomizing liquid, characterized in that a large number of uniform small droplets are generated by simultaneously applying high-frequency vibration to the entire container-like structure or to the perforated portion. 0 (2) A method for atomizing a liquid using the method set forth in claim 1 in a gas atmosphere. (3) A method for atomizing a liquid in a different liquid using the method according to claim 1. (4) A method for generating uniform-diameter solid particles by spray-drying a solution containing a solvent using the method set forth in claim 1. (5) An apparatus for carrying out the method set forth in claim 1.