JP2011098284A - Nozzle for mixing gas and liquid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nozzle for mixing a gas and a liquid capable of spraying a mixture of a gas and a liquid under a low supply pressure of the gas and of suppressing spray comprising particles of large particle diameters as generated in prior art spray. <P>SOLUTION: The nozzle 10 for mixing a gas and a liquid wherein an orifice 102 of its liquid ejecting member is disposed in an orifice 101 of its gas ejecting member in a manner of allowing the tip of the outlet of the orifice 101 of the gas ejecting member to protrude in the ejection direction relative to the tip of the outlet of the orifice 102 of the liquid ejecting member, with the outlet of the orifice 102 of the liquid ejecting member disposed in the vicinity of the inlet of the orifice 101 of the gas ejecting member, is characterized in that a part C connecting a gas supply path 12 of the gas ejecting member and the inlet of the orifice 101 of the gas ejecting member is rounded or tapered in the cross sectional view thereof. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a gas-liquid mixing (or two-fluid) nozzle, and more particularly, to a gas-liquid mixing nozzle in which an orifice outlet tip of a gas injection unit protrudes in an injection direction from an orifice outlet tip of a liquid injection unit. .

  In general, in the two-fluid nozzle, two pressures of a gas supply pressure and a liquid supply pressure are applied to atomize the liquid (the average particle diameter is about 10 to 50 μm, for example). As a mechanism for adjusting the supply liquid amount of the two-fluid nozzle, a needle is movably disposed inside the liquid circulation part, and the supply liquid amount is adjusted by reducing the orifice opening area by the movement of the needle.

  In recent years, atomization injection at a low gas supply pressure (for example, 100 kPa or less) has been demanded in various industrial fields. However, the liquid injection amount decreases as the gas supply pressure is lowered.

  Further, in a variety of commercially available gas-liquid mixing nozzles, a wide range in which the average particle diameter of liquid fine particles sprayed from the gas-liquid mixing nozzle is 10 to 200 μm under the conditions of an air pressure of 20 kPa to 500 kPa and a spraying flow rate of 1 to 1000 mL / min. Met. And the mist (for example, wet mist) with a large particle diameter in the liquid fine particles sprayed from the gas-liquid mixing nozzle tends to spread at a large angle with respect to the spraying direction from the gas-liquid mixing nozzle (see FIG. 7, “ See "Splashes"). A mist having a small particle diameter (for example, a dry mist or a haze) tends to be ejected on the spray direction axis from the gas-liquid mixing nozzle (see FIG. 7, atomized body). For example, when the spray half angle of the gas-liquid mixing nozzle of FIG. 7 is 15 °, the spray half angle is about 55 °, the average particle size of the spray particles is 50 to 100 μm, and the spray half angle is 15 °. The average particle size of was 10-20 μm. That is, the average particle diameter of the entire spray was increased due to the presence of splashes.

  By the way, a spray nozzle device for generating fine particle mist is known (Patent Document 1). This spray nozzle device has a first nozzle part and a second nozzle part, and can form a fine particle mist by colliding the spray liquid from the first nozzle part with the spray liquid from the second nozzle part. . However, since two two-fluid nozzle portions are provided, the cost is high and it is not suitable for downsizing. Moreover, it is not a structure suitable for making gas supply pressure low.

Japanese Patent Laid-Open No. 2002-126587

  The present invention has been made in view of the above circumstances, and an object of the present invention is to enable spraying of gas-liquid mixing under a low gas supply pressure and a spray having a large particle diameter like a conventional droplet. It is in providing the gas-liquid mixing nozzle which can suppress this.

In order to solve the above problems, the gas-liquid mixing nozzle of the present invention is configured so that the orifice outlet tip of the gas injection unit protrudes in the injection direction from the orifice outlet tip of the liquid injection unit. A gas-liquid mixing nozzle in which an orifice of an injection unit is disposed,
An orifice outlet part of the liquid injection part is disposed in the vicinity of the orifice inlet part of the gas injection part,
The connecting portion between the gas supply passage of the gas injection portion and the orifice inlet portion of the gas injection portion is subjected to R processing or taper processing in a cross-sectional view.

  In the gas-liquid mixing nozzle, the orifice of the liquid ejecting section is arranged in the orifice of the gas ejecting section so that the orifice exit end of the gas ejecting section protrudes in the ejecting direction from the orifice exit end of the liquid ejecting section. The injection amount of the liquid fine particles can be made larger than the configuration in which the positions of the orifice tip of the gas injection unit and the orifice tip of the liquid injection unit coincide with each other. And the orifice exit part of a liquid injection part is arrange | positioned in the orifice entrance part proximal to a gas injection part. “Proximal orifice inlet part of gas injection part” is the proximal part of the inlet part of the orifice of the gas injection part, and there is a configuration in which they are coincident with each other, and there is a configuration in which either one is back and forth. .

  In the conventional arrangement of the orifices of the gas injection part and the liquid injection part, the hollow cylindrical liquid orifice is configured so that the tip ends of the hollow cylindrical gas orifices coincide with each other. And the gas injected from a gas orifice is injected from the orifice exit (cross-sectional donut shape) substantially linearly, the shape expanding radially. At this time, since the gas supply pressure is high (for example, 200 kPa to 500 kPa), a negative pressure space is formed in the front side of the ejection side of the liquid orifice outlet, and the liquid supply pressure is substantially reduced by the liquid absorption force due to this negative pressure. Even without it, the liquid is ejected. In the conventional arrangement, the gas injection direction (air flow) is defined by the inner wall surface of the gas orifice and the outer wall surface of the liquid orifice as described above. However, as in the present invention, the gas orifice of the gas injection unit In the configuration in which the orifice outlet part of the liquid injection part is disposed in the vicinity of the inlet part, when the gas flows from the gas supply passage to the gas orifice inlet, the outer wall surface of the liquid orifice disappears, so that the injection is performed in the gas orifice. Gases merge together (from a cross-sectional donut shape to a cylindrical gas flow), and are ejected to the outside through a gas orifice. At this time, the jet gas flow in the gas orifice forms a negative pressure space (a negative pressure space higher than the conventional one or a stable negative pressure space) in the jet side front part of the liquid jet part orifice inlet, and the supply gas However, even if the pressure is lower than the conventional pressure (100 kPa or less), the liquid can be absorbed and ejected.

  Further, in the present invention, the continuous portion of the gas supply passage of the gas injection portion and the orifice inlet portion of the gas injection portion is subjected to R processing or taper processing in a sectional view. As a result, a smooth air flow is formed from the inner wall surface of the gas supply passage to the inner wall surface of the gas orifice, the flow velocity to the outlet of the gas orifice is increased, and the negative pressure space at the front side of the injection side of the liquid orifice inlet portion is reduced. Further, it can be formed in a higher negative pressure space than in the past or in a stable negative pressure space. Therefore, even when the gas supply pressure is low, the liquid-absorbing force is strong, gas-liquid mixed spraying is possible, and spraying with a large particle diameter such as a conventional droplet can be suppressed. In particular, in the present invention, even in the nozzle injection conditions and the nozzle internal shape in which the negative pressure space at the injection side front part of the liquid injection part orifice inlet part cannot be stably formed, the gas supply passage and the gas orifice inlet part Since the continuous portion is subjected to R processing or taper processing in a cross-sectional view, the formation of the negative pressure space is preferably improved, and liquid spraying is possible with high liquid absorption.

  Further, the present invention provides a case in which the injection gas flow reversely flows into the liquid injection unit orifice by arranging the orifice outlet unit of the liquid injection unit in the vicinity of the orifice inlet of the gas injection unit. However, the above-described continuous portion subjected to the R treatment or the taper treatment forms a smooth air flow from the inner wall surface of the gas supply passage to the inner wall surface of the gas orifice, and does not generate such a backflow. Can be suitably formed.

  The “continuous part of the gas supply passage of the gas injection part and the orifice inlet part of the gas injection part” may be a continuous structure in which separate bodies are connected to each other, or a continuous structure in which the gas injection part is an integral structure. “R processing” refers to normal R processing, which is a process of rounding off corners and protrusions. Further, the cross-sectional shape of the continuous portion after “R treatment” can be expressed by one or a plurality of curvatures or curvature radii. “Taper processing” refers to normal taper processing. In the present invention, “R treatment” may be applied to the corner after “taper treatment”. In addition, the “tapering process” may be to form a plurality of tapered portions (so-called polygonal shape in cross-sectional view). Further, the angle α (see FIG. 5) of the continuous portion including the gas supply passage and the orifice inlet is in the range of 90 ° or more and less than 180 °. For example, the angle α is exemplified by a range of 90 ° to 165 ° and a range of 110 ° to 145 °.

  As an embodiment of the above invention, the orifice of the liquid ejecting section is disposed within the orifice of substantially the same diameter of the gas ejecting section, and the respective central axes of the orifice of the gas ejecting section and the orifice of the liquid ejecting section coincide with each other. There is a configuration.

  “Substantially the same diameter orifice” means that a substantially straight orifice is formed, for example, the diameter of each of the orifice start end inside the nozzle and the orifice end end of the nozzle tip With the same processing accuracy (allows taper angle), or a concept that includes forming the straight portion with the diameter of the orifice end portion within + -10% of the diameter of the orifice start end portion. is there.

  As other constituent members of the gas-liquid mixing nozzle, known members can be used. For example, the constituent members can be made of metal, plastic, rubber, or a mixture thereof. The “gas” supplied to the gas-liquid mixing nozzle is not particularly limited, and examples thereof include gases such as air, clean air, high oxygen concentration air, and inert gas. In addition, the “liquid” supplied to the gas-liquid mixing nozzle is not particularly limited, but is a cosmetic solution such as water, ionized water, and lotion, a chemical solution such as a pharmaceutical solution, a bactericidal solution, a sterilizing solution, a paint, a fuel oil, A coating agent, a solvent, resin, etc. are mentioned.

  The supply pressure of the gas supplied to the gas-liquid mixing nozzle device is, for example, a low pressure condition of 5 kPa to 50 kPa, preferably 5 kPa to 40 kPa, more preferably 5 kPa to 30 kPa, and even more preferably 5 kPa to 20 kPa. The supply pressure of the liquid is free, for example, there is no external action such as the supply pressure of the liquid. Under these conditions, the nozzle can be directed upward, the liquid can be sucked up by gas jetting action, gas-liquid mixed, and liquid fine particles can be generated and jetted. In particular, in the present invention, the negative pressure space can be suitably formed by forming a smooth air flow from the inner wall surface of the gas supply passage to the inner wall surface of the gas orifice by the continuous portion subjected to R processing or taper processing. Therefore, liquid fine particles can be generated even with such low energy. Since the gas supply pressure can be reduced, a drive source (for example, a compressor, an air pump, a power source, a compressed air cylinder, a manual air supply mechanism) necessary for gas supply of the gas-liquid mixing nozzle can be reduced in size.

It is a cross-sectional schematic diagram which shows the example of a gas-liquid mixing nozzle. It is a cross-sectional schematic diagram which shows the example of a gas-liquid mixing nozzle front-end | tip part. It is a cross-sectional schematic diagram which shows the example of a connection part. It is a figure for demonstrating airflow. It is a cross-sectional schematic diagram for demonstrating arrangement | positioning and a connection part of a water orifice and an air orifice. It is a figure for demonstrating the spraying state of the gas-liquid mixing nozzle of this application. It is a figure for demonstrating the spraying state of the conventional gas-liquid mixing nozzle.

  Below, a gas-liquid mixing nozzle is demonstrated using figures. FIG. 1 is a cross-sectional view of the gas-liquid mixing nozzle 10. The gas-liquid mixing nozzle 10 includes a gas supply unit 11 that supplies gas, a gas supply passage 12 that circulates gas from the gas supply unit 11 to the gas orifice 101 of the gas injection unit, and a liquid orifice 102 of the liquid injection unit. And a liquid orifice 102 disposed inside the gas orifice 101 as shown in FIGS. A liquid orifice outlet part is disposed in the vicinity of the gas orifice inlet part (continuous part C) of the gas injection part.

  FIG. 3 is an enlarged cross-sectional view of the continuous portion C in FIG. FIG. 3A shows a shape (301) in which the continuous portion C is subjected to R processing, and FIG. 3B shows a shape (302) in which the continuous portion C is subjected to taper processing. In FIG.4 (b), the airflow in the continuous part C vicinity area | region is shown by the arrow. As shown in FIG. 4B, a smooth air flow can be formed along the inner wall surface of the gas orifice 101 from the inner wall surface of the gas supply passage 12 to increase the flow velocity to the outlet of the gas orifice 101, and the inlet of the liquid orifice 102 Thus, the negative pressure space in the front portion of the injection side can be a negative pressure space higher than the conventional one and a stable negative pressure space can be formed. On the other hand, FIG. 4A shows an air flow when the continuous portion C is not subjected to the R treatment or the taper treatment by an arrow, and according to this, the air flow is caught in the outlet portion of the liquid orifice 102, In some cases, the negative pressure space is not preferably formed even when the pressure of the supply gas is low or unstable. However, as in this configuration, the continuous portion C is R-processed or tapered. By performing the treatment, the negative pressure space can be suitably formed.

  2 and 5, the tip of the gas orifice 101 protrudes from the tip of the liquid orifice 102 in the ejection direction. The liquid orifice 102 is disposed in the gas orifice 101 having substantially the same diameter, and the central axes in the straight direction of the gas orifice 101 and the liquid orifice 102 coincide with each other. The tip of the liquid orifice 102 is disposed in the vicinity of the continuous portion C (or the start end portion of the gas orifice) of the gas orifice 101. Hereinafter, the gas orifice may be referred to as an air orifice, and the liquid orifice may be referred to as a water orifice.

  The position of the outlet end of the liquid orifice 102 disposed in the vicinity of the continuous portion C is a distance of ± 5% of the straight length of the gas orifice 101 from the inlet portion of the gas orifice 101. Alternatively, the distance from the gas orifice 101 inlet to the liquid orifice 102 outlet tip (see L2 FIG. 5) is preferably in the range of −0.1 mm to 0.1 mm, more preferably −0.05 mm to 0.05 mm, − 0.02 mm to 0.02 mm is more preferable.

(Example)
The air orifice outer diameter (φda [mm], see FIG. 5) is 0.55, the air orifice inner diameter (φdb [mm]) is 0.50, and the water orifice diameter (φdb [mm]) is 0.30, 0.33. , 0.35. The continuous part C was R-processed. The angle α of the continuous portion is 135 °. The throttle angle of the gas supply passage 12 is 90 °. L2 is zero at the water orifice tip position in the air orifice. Table 1 shows the results of measurement of the total water injection amount (Qw [ml / min]) at an air pressure Pa of 23 kPa and an air flow rate Qa of 1.09 [NL / min]. The gas-liquid mixing nozzle is left stationary with the injection direction facing upward, water is supplied in advance so that the liquid level is -25 mm from the tip of the water orifice, and the total water injection amount (Qw at the above three types of air pressure) ) Was measured. The straight length dimension of the air orifice 101 (see L1 FIG. 5) is 0.51 mm. A compressor was used as the air supply drive source.

(Comparative example)
The comparative example is the same as the above embodiment except that the R process is not performed on the continuous portion C.

  In FIG. 6, the injection state of Examples 1 to 3 is shown. In any of Examples 1 to 3, it was confirmed that the conventional splash generation as shown in FIG. 7 could be suitably suppressed. Further, from the results shown in Table 1, it was possible to suitably inject at any water orifice diameter (φdw). On the other hand, none of Comparative Examples 1 to 3 was jetted.

(Other examples)
It is the same as that of the said Example 1 to 3 except having formed the taper shown in FIG.3 (b) in the continuous part C instead of said R process. In the same manner as described above, it was confirmed that injection was possible suitably.

C connected portion 10 gas-liquid mixing nozzle 12 gas supply passage 101 gas orifice 102 liquid orifice 301 R treatment forming portion 302 taper portion

Claims (3)

A gas-liquid mixing nozzle in which the orifice of the liquid ejecting unit is disposed in the orifice of the gas ejecting unit so that the orifice exit leading end of the gas ejecting unit protrudes in the ejecting direction from the orifice exit leading end of the liquid ejecting unit,
An orifice outlet part of the liquid injection part is disposed in the vicinity of the orifice inlet part of the gas injection part,
A gas-liquid mixing nozzle, wherein a continuous portion of the gas supply passage of the gas injection unit and the orifice inlet of the gas injection unit is subjected to R processing or taper processing in a sectional view.   2. The gas-liquid mixing nozzle according to claim 1, wherein an air flow is generated along the shape of the continuous portion subjected to the R treatment or the taper treatment. The gas-liquid mixing nozzle according to claim 1, wherein the liquid is atomized and jetted at a low gas supply pressure.

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