JP4917803B2 - Fine bubble jet nozzle and fine bubble generator using the same - Google Patents

Description

  The present invention relates to a fine bubble jet nozzle attached to a liquid storage tank such as a bathtub and a fine bubble generator using the same, and more particularly to a novel configuration of a fine bubble jet nozzle that can use a low-capacity pump and has a silencing effect. .

  So-called bubble baths are usually bubble baths and fine bubble baths. In normal bubble baths, air is mixed with pressurized liquid to generate relatively large bubbles in the bathtub, while in bubble baths, Is melted under pressure in hot water, the hot water is supplied to the bathtub and fine bubbles are ejected into the bathtub to become cloudy. This application provides the novel structure of the fine bubble jet nozzle for spouting the hot water which was attached to the bathtub for the fine bubble bath and which pressurized and melted air to the bathtub.

  The fine bubble generator uses a pressure pump such as a vane pump to pressurize and dissolve air in hot water, separate the undissolved excess air from the hot water, and supply hot water containing dissolved air from a fine bubble jet nozzle provided in the bathtub. It spouts into the bathtub and generates fine bubbles. In the fine bubble bath, fine bubbles are jetted into the bathtub, and the inside of the bathtub becomes clouded or milky white, and a special bathing feeling is obtained.

The fine bubble generator is described in Patent Documents 1, 2, and 3, for example.
JP-A-6-165806 Japanese Patent Laid-Open No. 5-212082 Japanese Utility Model Publication No. 3-70753 Microfilm

  The fine bubble jet nozzle has a small nozzle diameter, and the hot air containing dissolved air is ejected from the jet hole at a high speed to precipitate the dissolved air in the liquid due to the pressure drop and generate fine bubbles. However, the area around the nozzle outlet is in a negative pressure state by Bernoulli's theorem, a boiling state is generated due to the lowering of the boiling point due to the negative pressure, and large bubbles are generated in the liquid. The problem is that a metallic sound) occurs. In addition, the large bubbles mentioned above are not caused by the generation of fine bubbles due to white turbidity in the bath. Therefore, it is necessary to dissolve a large amount of air in the liquid with a high-capacity pressure pump. There is also a problem in that the pressurizing pump increases the cost.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a fine bubble ejection nozzle that can reduce cavitation noise and reduce the capacity of a pressure pump, and a fine bubble generator using the same.

In order to achieve the above object, according to the first aspect of the present invention, in a fine bubble jet nozzle attached to a liquid storage tank and jetting a liquid obtained by pressurizing and dissolving air into the liquid storage tank,
A nozzle body that is supplied with the liquid and has an ejection hole that is provided at a tip portion and ejects the liquid;
A nozzle cover having a wall member attached to the tip of the nozzle body and provided at a position facing the ejection hole, and an orifice provided at a position spaced from the ejection hole;
The liquid supplied to the nozzle body is ejected from the ejection hole toward the wall member, and is further ejected to the outside from the orifice.

In order to achieve the above object, according to the second aspect of the present invention, in the fine bubble jet nozzle attached to the liquid storage tank and jetting the liquid obtained by pressurizing and dissolving air into the liquid storage tank,
A nozzle body provided with the liquid, provided on a side surface of the tip, and having a plurality of ejection holes for ejecting the liquid in a circumferential direction;
A nozzle cover having a side wall member attached to the tip of the nozzle body and provided at a position facing the ejection hole, and a bottom surface member provided with an orifice for ejecting liquid ejected from the ejection hole to the outside. Have
The liquid supplied to the nozzle body is ejected from the plurality of ejection holes toward the side wall member, and is further ejected to the outside from the orifice.

  In the second aspect, in a preferred aspect, the inner wall of the side wall member of the nozzle cover is provided with an uneven shape.

  According to the above aspect of the present invention, the nozzle cover is provided at the tip of the nozzle body, and the pressure of the ejected liquid gradually decreases, so that a large amount of large bubbles are generated around the ejection holes ejected to the outside, and a large metal Generation of sound is suppressed. In addition, by suppressing the generation of large bubbles, sufficient air can be dissolved in the liquid even if the capacity of the pressurizing pump is lowered, and the cost can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the technical scope of the present invention is not limited to these embodiments, but extends to the matters described in the claims and equivalents thereof.

  FIG. 1 is a cross-sectional view for explaining problems of a conventional fine bubble ejection nozzle. A nozzle NZ is attached to the bathtub 20, hot water pressurized in the direction of the arrow and containing dissolved air is supplied, and hot water is ejected from the nozzle outlet 50. The hot water 52 ejected at a high speed from the nozzle outlet 50 is returned from the high pressure state to the atmospheric pressure state, and accordingly, dissolved air is precipitated and the fine bubble group 24 is generated.

  However, the periphery 54 of the high-speed jet water 52 is in a negative pressure state by Bernoulli's theorem. As a result, the surrounding 54 becomes a boiling state and large bubbles are generated. When the large bubbles are repelled, a loud metal sound (cavitation sound) is generated.

  In addition, since the amount of fine bubbles generated in the bathtub is reduced due to the generation of large bubbles, it is necessary to increase the capacity of the pressure pump to dissolve more air. Such a high-capacity pressurizing pump increases the cost of the microbubble generator.

  FIG. 2 is a diagram showing the overall configuration of the bubble generating device in the present embodiment. The outward piping 12 and the return piping 14 of the hot water heater 10 for remedy are connected to the bathtub 20 via the remedy nozzle NZ1. The water heater 10 includes a heat exchanger 1, a burner 2 for supplying heat to the heat exchanger 1, and a gas on-off valve 4 for supplying gas to the burner. Furthermore, a retreat pump P0 and a running water switch SW are provided in the circulation line connected to the return pipe 14 through which hot water is returned from the bathtub. When the remedy pump P0 is turned on by control from a control unit (not shown) and the running water switch SW is confirmed to be on, the presence of remaining hot water in the bathtub is confirmed, the gas on-off valve 4 is opened, and the amount of heat from the burner 2 is increased. It is thrown. Thereby, circulating hot water is heated via the heat exchanger 1, and hot water in a bathtub is memorized.

  In FIG. 2, a bubble generator 30 is provided in addition to the hot water heater 10, the return pipe 36 of the bubble generator 30 is connected to the outgoing pipe 12 of the memorial circulation line, and the outgoing pipe 38 of the bubble generator 30 is fine. It is connected to the bathtub 20 via the bubble ejection nozzle NZ2. The bubble generator 30 includes an air supply valve 32 that mixes air into the hot water, a vane pump P1 that pressurizes hot water mixed with air and dissolves the air, and pressurizes hot water containing dissolved air into the bathtub at high speed. A vortex pump P2 for jetting and an air vent valve 34 for venting excess air are provided.

  The hot water in the bathtub circulates in the bubble return pipe 36 branched from the follow-up pipe 12, and the air mixed in the supply valve 32 by the pressurizing vane pump P1 for dissolving the air is increased in pressure in the circulating hot water. And is circulated to the bubble forward pipe 38 via the centrifugal pump P2 and the air vent valve 34, and is ejected from the fine bubble ejection nozzle NZ2 into the bathtub 20 to generate the fine bubbles 24.

  FIG. 3 is a diagram illustrating a configuration example of the vane pump. In the vane pump, the rotor shaft 42 eccentrically attached in the casing 40 rotates, so that the extendable vane (blade plate) 41 attached to the rotor shaft 42 rotates. From the inlet 46 as indicated by an arrow. The entering liquid is pressurized and the pressurized liquid is sent out from the outlet 48. It is shown that the rotor shaft 42 rotates from the state of FIG. 3 (1) to the state of (2), and the liquid pressurized by the vane 41 is sent out. FIG. 3 is merely an example of a vane pump, and other configurations are applicable to the present embodiment.

  FIG. 4 is a diagram of a fine bubble ejection nozzle in the present embodiment. A cross-sectional view is shown on the left and a bottom view is shown on the right. In the fine bubble jet nozzle NZ2, a nozzle cover 64 is rotatably mounted on the tip of a nozzle body 60 having a fine jet hole 62 by, for example, a screw mechanism. A liquid containing dissolved air is supplied to the nozzle body 60 in the direction of the arrow, and the wall 65 of the nozzle cover 64 is positioned opposite the ejection hole 62, and the liquid that has come out of the nozzle hole 62 flows into the bathtub by the wall 65. Direct opening is prevented, and as shown by an arrow, the nozzle cover 64 bypasses the nozzle cover 64 and is jetted into the bathtub from a plurality of orifices 66 provided on the bottom surface of the nozzle cover 64. As shown in the bottom view on the right side, a plurality of orifices 66 are provided on the bottom surface of the nozzle cover 64 at positions spaced from the ejection holes 62 so as to surround the ejection holes 62 of the nozzle body 60.

  By providing such a nozzle cover 64 at the tip of the nozzle body 60, it is possible to suppress a large metal sound of the conventional fine bubble ejection nozzle and generate sufficient fine bubbles even with a low-performance pressure pump. The reason is considered as follows.

  A liquid in which air is melted by a pressure pump such as a vane pump is supplied to the nozzle body 60 in the direction of the arrow. When the pressure of the liquid in the nozzle body is V1, the liquid pressure ejected from the ejection hole 62 of the nozzle body 60 and in the nozzle cover 64 is V2, and the liquid pressure ejected from the orifice 66 of the nozzle cover 64 is V3. Then, the relation of V1> V2> V3 is established. That is, the pressure of the liquid in the nozzle body 60 slightly decreases in the nozzle cover 64 and is ejected from the orifice 66 of the nozzle cover 64 to be reduced to the pressure in the atmosphere open state. In the liquid ejected from the orifice 66, dissolved air is precipitated due to a pressure drop, and fine bubbles are generated.

  Accordingly, the pressure of the pressurized liquid gradually decreases to V1 (inside the orifice body), V2 (inside the orifice cover), and V3 (outside), so that the negative pressure state at the nozzle outlet shown in FIG. It is considered that the generation of large bubbles is suppressed. As a result, the loud metal sound caused by the bursting of large bubbles is suppressed. Further, even if a large bubble is generated in the ejection hole 62 of the nozzle body 60, the metal sound is considered to be silenced by the nozzle cover 64.

  Therefore, the nozzle cover 64 has a wall 65 that faces the ejection hole 62 of the nozzle body 60, and may have a plurality of orifices 66 that eject liquid that has been prevented from being directly opened to the outside by the wall 65. is necessary.

  FIG. 5 is a diagram of another fine bubble ejection nozzle in the present embodiment. The fine bubble ejection nozzle NZ2 has a nozzle cover 64 attached to the tip of the nozzle body 60. In this example, the nozzle cover 64 has a wall 65 on the bottom surface and a plurality of orifices 66 on the side surface. The orifice 66 is at a position spaced from the ejection hole 62. As shown in the right side view, a plurality of orifices 66 are provided on the side surface of the nozzle cover 64 so as to surround the nozzle body 60. Therefore, the liquid supplied from the nozzle body 60 as shown by the arrow collides with the bottom wall 65 of the nozzle cover 65 from the ejection hole 62 at the tip of the nozzle body 60 and is prevented from opening to the outside as shown by the arrow. Then, the liquid is discharged from the side orifice 66 to the outside. The high-speed liquid ejected from the orifice 66 is released to the atmospheric pressure, the pressure is lowered, and the dissolved air is precipitated to generate cloudy fine bubbles.

  FIG. 6 is a diagram of still another fine bubble ejection nozzle in the present embodiment. 6A is a cross-sectional view taken along the line X-X in which the nozzle body is cut in the vertical direction, and FIG. This nozzle also has a nozzle cover 64 attached to the tip of the nozzle body 60. Then, three ejection holes 61 directed in the circumferential direction are provided in the side wall at the tip of the nozzle body 60, and the bottom surface of the tip is closed. On the other hand, the nozzle cover 64 is provided with a side wall 65 that prevents the liquid ejected from the ejection hole 61 of the nozzle body 60 from being directly opened to the outside, and a bottom surface provided with one orifice 66 that ejects the liquid to the outside. 67.

  The liquid containing dissolved air that has been pumped in the direction of the arrow of the nozzle body 60 passes through the ejection hole 61 provided in the tip side wall of the nozzle body and collides with the side wall 65 of the nozzle cover 64, so that the tangential direction or circle of the nozzle body The direction is changed in the circumferential direction, and it is ejected downward from the orifice 66 on the bottom surface of the nozzle cover 64 in the figure. As a result of this jetting, the pressure of the liquid is reduced to atmospheric pressure, and dissolved air is deposited to generate cloudy fine bubbles. In particular, the pressure-fed liquid flows through the nozzle cover 64 in the circumferential direction by the plurality of ejection holes 61 directed in the circumferential direction on the side wall of the nozzle body 60, and the pressure is once reduced. Then, liquid is ejected from the orifice 66 of the nozzle cover 64. Also in this case, the relationship between the liquid pressures is V1> V2> V3 as described above, and the liquid pressure V2 ejected from the orifice 66 is lower than the pressure V1 in the nozzle body. It seems that the degree of negative pressure around the flow is reduced and the generation of large bubbles is reduced. As a result, generation of a loud metallic sound called keen is also suppressed.

  FIG. 7 is a diagram of still another fine bubble ejection nozzle in the present embodiment. FIG. 7A is a cross-sectional view taken along the line X-X in which the nozzle body is cut in the vertical direction, and FIG. The XX sectional view of FIG. 7 (1) is the same as FIG. 6 (1). However, as shown in the YY sectional view of FIG. 7B, a plurality of grooves extending in the vertical direction are formed on the inner side wall of the nozzle cover 64. In the YY sectional view, the inner wall of the nozzle cover 64 is Has an uneven structure.

  Therefore, in the case of the nozzle example in FIG. 7 as well, as in the nozzle in FIG. 6, a liquid containing dissolved air is ejected from the nozzle body 60 through the ejection hole 61 into the nozzle cover 64, the pressure is lowered, and the nozzle It is ejected from the orifice 66 to the outside of the cover 64. And the air which melt | dissolved by the external low pressure precipitates, and a fine bubble is generated.

  In the case of the fine bubble ejection nozzle of FIG. 7, a plurality of ejection holes 61 directed in the circumferential direction (tangential direction) are provided on the side wall of the tip portion of the nozzle body 60, and the liquid ejected from the ejection holes 61 is not covered by the nozzle cover. Collide with 64 inner walls. Since the inner wall is provided with a concavo-convex structure, large bubbles generated when liquid is ejected from the ejection holes 61 collide with the concavo-convex structure on the inner wall of the nozzle cover 64 and are crushed into fine bubbles. Therefore, large bubbles are not ejected from the nozzle cover 64 to the outside. Further, the pressure of the liquid in the nozzle cover 64 is slightly reduced, so that the negative pressure around the high-speed flow ejected from the orifice 66 of the nozzle cover 64 is alleviated. Occurrence is suppressed.

  The uneven shape of the inner wall of the nozzle cover 64 is not necessarily limited to the shape of the groove extending in the vertical direction as shown in FIG. An uneven shape by a groove extending in the horizontal direction may be used.

  As described above, the fine bubble ejection nozzle of the present embodiment is provided with a nozzle cover at the tip of the nozzle body, and the liquid ejected from the ejection holes of the nozzle body once drops the pressure via the nozzle cover. , And then ejected to the outside. Therefore, the degree of pressure drop of the liquid is alleviated, and accordingly, the generation of large bubbles is suppressed and the metal sound is suppressed. In addition, since the amount of large bubbles is reduced, the air dissolved in the liquid is efficiently deposited as fine bubbles in the bath, so that even if the amount of dissolved air in the liquid is reduced, sufficient cloudiness is achieved. Fine bubbles can be generated. Therefore, if the fine bubble ejection nozzle according to the present embodiment is used, the ability of the vane pump (pressure pump) of the bubble generator can be lowered, and the cost can be reduced accordingly.

It is sectional drawing for demonstrating the problem of the conventional fine bubble ejection nozzle. It is a figure which shows the whole structure of the bubble generator in this Embodiment. It is a figure which shows the structural example of a vane pump. It is a figure of the fine bubble ejection nozzle in this Embodiment. It is a figure of another fine bubble ejection nozzle in this Embodiment. It is a figure of another fine bubble ejection nozzle in this Embodiment. It is a figure of another fine bubble ejection nozzle in this Embodiment.

Explanation of symbols

60: Nozzle body 61: Ejection hole 64: Nozzle cover 65: Side wall 66: Orifice

Claims (4)

In a fine bubble jet nozzle that is attached to a liquid storage tank and jets liquid that has been pressurized and dissolved into the liquid storage tank.
A nozzle body that is supplied with the liquid, the bottom surface of the tip portion is closed, and is provided on a side surface of the tip portion, and has a plurality of ejection holes for ejecting the liquid in a circumferential direction;
A nozzle cover having a side wall member attached to the tip of the nozzle body and provided at a position facing the ejection hole, and a bottom surface member provided with an orifice for ejecting liquid ejected from the ejection hole to the outside. Have
The liquid supplied to the nozzle body, fine bubble ejection nozzles, wherein the plurality of jet holes toward the side wall member erupted the circumferential direction, further ejected from the orifice to the outside. 2. The fine bubble ejection nozzle according to claim 1 , wherein an uneven shape is provided on an inner wall of the side wall member of the nozzle cover. In a fine bubble generating device for generating fine bubbles in a liquid storage tank by jetting a liquid in which air is dissolved under pressure into the liquid storage tank,
A pressurizing pump for pressurizing and dissolving air in the liquid;
A pipe for pumping liquid in which air is dissolved by the pressure pump;
A fine bubble ejection nozzle provided in the liquid storage tank and connected to the pipe;
The fine bubble jet nozzle is provided with the liquid, the bottom surface of the tip portion is closed, the nozzle body is provided on the side surface of the tip portion and has a plurality of jet holes for jetting the liquid in the circumferential direction, and the nozzle A nozzle cover having a side wall member attached to the tip of the main body and provided at a position facing the ejection hole, and a bottom surface member provided with an orifice for ejecting liquid ejected from the ejection hole to the outside; , liquid supplied to the nozzle body, the plurality of the direction from the jet holes in the side wall member erupted the circumferential direction, the fine bubble generating device, characterized in that it further ejected from the orifice to the outside. 4. The fine bubble generating device according to claim 3 , wherein an uneven shape is provided on the inner wall of the side wall member of the nozzle cover.

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