JP4561738B2 - Microbubble generator - Google Patents

Description

  The present invention relates to a fine bubble generator that can reduce injection noise.

2. Description of the Related Art Conventionally, there is a fine bubble generating device in which a gas-liquid dissolved fluid in which a gas is pressurized and dissolved in a liquid is released by a decompression unit and ejected and discharged from a discharge nozzle into a bathtub while generating fine bubbles ( Patent Document 1).
JP-A-11-33071

  However, there has been a problem that the injection noise when fine bubbles are generated by the discharge nozzle is directly radiated from the bathtub into the bathroom.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a fine bubble generator capable of effectively reducing injection noise.

In order to solve the above-mentioned problems, the present invention provides a method for generating fine bubbles in which a gas-liquid dissolved fluid in which a gas is pressurized and dissolved in a liquid is depressurized by a decompression unit and ejected and discharged from a discharge nozzle while generating fine bubbles. In the apparatus, a venturi tube as the pressure reducing means is provided in the nozzle body of the discharge nozzle, and a cylindrical protrusion that protrudes in the discharge direction from the discharge port of the venturi tube is formed. Provided is a fine bubble generating device characterized in that a cylindrical sound-absorbing sheet is fitted and held on a peripheral surface, and the sound-absorbing sheet is formed in a hard part near the discharge port of a venturi tube. Is.

  According to a second aspect of the present invention, a plurality of the venturi tubes can be provided in parallel.

According to a third aspect of the present invention, it is preferable that a cylindrical silent mesh made of a wire mesh is fitted and held on the inner peripheral surface of the sound absorbing sheet.

According to the present invention, the cylindrical sound-absorbing sheet is held on the inner peripheral surface of the cylindrical protruding portion that protrudes in the discharge direction from the discharge port of the venturi pipe of the nozzle body, so that the surface of the sound-absorbing sheet is The noise is reduced by the rectifying action of the fine vortex flow, and the injection noise generated in the discharge nozzle, that is, the venturi pipe is effectively reduced by the absorption and damping action of the pulsation by the sound absorbing sheet. Further, by providing a sound absorbing sheet in the vicinity of the protruding portion of the nozzle body, that is, the outlet of the venturi pipe, which is an injection noise source, the injection noise can be more effectively reduced.
In addition, the sound absorbing sheet is usually soft and prevents the generation of fine bubbles in the vicinity of the venturi discharge port. However, by making the vicinity of the venturi discharge port a hard part, the generation of fine bubbles Will not be disturbed.

  According to the second aspect, in the case where a plurality of venturi pipes are provided in parallel, the injection noise generated in each venturi pipe can be collectively reduced.

According to the third aspect of the present invention, since the cylindrical silent mesh made of a wire mesh is held on the inner peripheral surface of the sound absorbing sheet by an internal fit, it is generated at the discharge nozzle due to the diffusion attenuation (rectification) action of the pulsation by the silent mesh. The injection noise is reduced more. Further, since the sound absorbing sheet is disposed on the back side of the silent mesh, the sound absorbing sheet does not become a resistance to the jet liquid flow, and the sound absorbing sheet does not scatter in the jet liquid flow. Furthermore, a sound absorbing sheet and a silent mesh can be incorporated into a nozzle body having a venturi tube to form a unit.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a basic configuration diagram of a microbubble generator that generates microbubbles in bath water in a bathtub 1, for example, and a suction port 2 and a discharge port 3 are provided on the inner surface of the bathtub 1. An air inlet 4 is provided in the flange portion.

  The suction port 2 is connected to the suction side of the pump 6 through the connection pipe 5, and the discharge side of the pump 6 is connected to the injection port 9 on the suction side of the gas dissolving device 8 through the inflow pipe 7. The outlet 10 on the discharge side of the gas dissolving device 8 is connected to one end of a venturi pipe 12 serving as a pressure release portion via an outflow pipe 11, and the other end of the venturi pipe 12 is connected to the side surface of the bathtub 1 via a connection pipe 13. Is connected to the discharge port 3 installed in the. The air suction port 4 is connected to an inflow pipe 7 between the pump 6 and the gas dissolving device 8 via a connection pipe 14, and a check valve 15 is provided in the connection pipe 14.

  And when the hot water which gas melt | dissolved is discharged in the bath water in the bathtub 1 from the discharge outlet 3, dissolved gas will precipitate in bath water and a fine bubble will come to be generated.

  As shown in detail in FIG. 2 and FIG. 3, the gas dissolving device 8 includes a side wall portion 21 having a straight cylindrical shape with a circular cross section, and end wall portions 22 that close both ends of the side wall portion 21. The center axis A (refer to the one-dot chain line in FIG. 2) of the side wall portion 21 that is formed of the cylindrical body 23 and has a longitudinal direction, that is, substantially cylindrical, is 10 to 45 degrees with respect to the horizontal direction (see the arrow in FIG. 2). It is arrange | positioned with the attitude | position which inclines with the inclination-angle (theta) of this.

  The cylindrical body 23 in this inclined posture has an upper end serving as an upstream A end, and a lower end serving as a downstream B end. An injection port 9 for injecting into the cylindrical body 23 is formed, and an outflow port 10 through which liquid flows out from the cylindrical body 23 is formed on the downstream side B.

  In the cylindrical body 23, a gas such as air, which becomes a solute, and a liquid such as water, which becomes a solvent, are stored, and is approximately in the vicinity of the vertical center of the substantially cylindrical side wall portion 21. The interface 24 between the gas and the liquid is located, and the portion on the upstream side A above the interface 24 becomes the gas storage portion 25 where the gas is stored, and the portion on the downstream side B from the interface 24 stores the liquid. It becomes the liquid storage part 26 to be performed.

  The injection port 9 is located on the inner wall surface of the gas reservoir 25 (the inner wall surface of the side wall 21 or the end wall 22 on the upstream side A from the interface 24), at a position near the interface 24, or slightly below the interface 24. It is formed on the inner wall surface of the liquid reservoir 26 (inner wall surface of the side wall 21 on the downstream side B from the interface 24). The inner wall surface of the side wall portion 21 or the end wall portion 22 is formed.

  The side wall 21 of the cylindrical body 23 is formed with an air vent 27 provided with a valve (not shown). The position of the air vent 27 is stored in the gas reservoir 25 and the gas reservoir 26. It becomes the level of the interface 24 of the liquid stored in.

  Next, the operation of the gas dissolving device 8 will be described. When the same liquid and gas stored in the cylindrical body 23 are jetted from the jet port 9, they collide with the inner wall surface on the upper side of the side wall portion 21 facing the jet port 9 and bounce off the inner wall surface. The liquid collides with the liquid stored in the liquid reservoir 26 at the interface 24 and is agitated. Further, the liquid stored in the liquid storage unit 26 is not only stirred by the gas-liquid mixed fluid colliding with the interface 24, but also by the gas-liquid mixed fluid injected into the cylindrical body 23 from the injection port 9. Stir.

  As described above, the gas stored in the cylindrical body 23 and the like by the agitation due to the collision with the inner wall surface of the side wall portion 21 of the gas-liquid mixed fluid, the collision at the interface 24, the agitation of the liquid when being jetted, and the like The liquid, the gas in the gas-liquid mixed fluid, and the liquid are mixed, and dissolution of the gas into the liquid is promoted. That is, the bubbles (gas) mixed in the liquid are subdivided by shearing by mixing and stirring, and the total surface area in contact with the liquid is increased. In addition, the dissolved concentration of the gas near the interface between the liquid and the gas is increased. Since it is reduced by homogenization by mixing and stirring, and the dissolution rate of the gas in the liquid increases, dissolution of the gas in the liquid is promoted.

  The liquid in which the dissolution of the gas has progressed is stored in the liquid storage portion 26 of the cylindrical body 23, but many undissolved bubbles are mixed in the stored liquid, and these bubbles become denser as they go upward. There are few bubbles near the lower end of the liquid reservoir 26, and there are almost no large bubbles. Then, the dissolution of the gas proceeds, and the liquid at the lower end of the liquid storage part 26 in which there are almost no large bubbles flows out from the tubular body 23 through the outlet 10.

  FIG. 4 is a basic configuration diagram of the venturi tube 12. The venturi pipe 12 of the outflow pipe 11 has a two-stage configuration including one upstream venturi pipe 12a in the center and a plurality (five in the example of FIG. 4) downstream venturi pipes 12b. In this way, by providing a plurality of downstream venturi pipes 12b in parallel, the bubbles in the gas-liquid mixture are crushed into small bubbles to some extent by the upstream venturi pipe 12a, and then the downstream venturi pipe 12b. Since smaller bubbles can be formed, a larger amount of smaller bubbles can be generated.

  FIGS. 5 and 6 are microbubble generators embodying the basic configuration of FIGS. 1 to 4, and the same configuration as the basic configuration is denoted by the same reference numeral, and detailed description thereof is omitted.

  A discharge nozzle 30 is attached to the side wall 1a (see FIG. 6) of the bathtub 1, and the above-described suction port 2, discharge port 3, venturi tube 12 (12a, 12b) and the like are incorporated into the discharge nozzle 30 as a unit. ing.

  The discharge nozzle 30 is provided with an L-shaped nozzle case 31 in a side view, and an L-shaped flow path 31a following the outer shape is formed inside the nozzle case 31. The outlet pipe 11 is connected to the inlet side (vertical portion) via an O-ring 32, and the central upstream venturi pipe 12a is fitted into the inlet-side flow path 31a. .

  A nozzle body 29 in which the plurality of downstream venturi pipes 12b are formed is fitted into an outlet side (laterally directed portion) flow path 31a via an O-ring 33.

  As shown in detail in FIGS. 9 (a) and 9 (b), the nozzle body 29 has a cylindrical fitting portion for fitting into the outlet side (lateral portion) of the nozzle case 31 via the O-ring 33. 29a, a cylindrical protruding portion 29b protruding forward (discharge direction) from the fitting portion 29a, and a plate-like blocking portion 29c formed between the cylindrical protruding portion 29b and the fitting portion 29a. The inner and outer double concentric circles are set in 29c, and a plurality of (six in this example) downstream venturi tubes 12b are formed at equal circumferential intervals along the inner small-diameter circle. A plurality (10 in this example) of the downstream venturi pipes 12b are formed along the radial circle at equal angular intervals on the circumference (a total of 16 downstream venturi pipes 12b in this example).

  Returning to FIG. 6, referring to FIG. 7, a cylindrical sound absorbing sheet 35 is fitted on the inner peripheral surface of the protruding portion 29 b of the nozzle body 29, and on the inner peripheral surface of the sound absorbing sheet 35, A cylindrical silent mesh (metal mesh) 36 is fitted inside, and the female screw 37a of the cylindrical mesh holder 37 is screwed into the male screw 29d at the front end of the protruding portion 29b, whereby the sound absorbing sheet 35 and the silent sound are inserted into the protruding portion 29b. The mesh 36 is held so as not to move. The silent mesh 36 may be provided as necessary.

  The sound-absorbing sheet 35 is preferably, for example, EPDM (foamed material such as rubber or elastomer). Moreover, you may use a nonwoven fabric. The silent mesh 36 is preferably, for example, a SUS metal mesh of about 100 mesh, and may be a punching metal.

  A packing 40 having a U-shaped cross-section is fitted into the mounting hole 1b of the side wall 1a of the bathtub 1 and the flange portion 31b on the outlet side (sideways portion) of the nozzle case 31 is applied to the packing 40 from the outside of the bathtub 1. In addition, the external thread 41a at the rear end portion of the cylindrical fixing flange 41 is screwed into the internal thread 31c of the flange portion 31b of the nozzle case 31 from the inside of the bathtub 1 so that the flange portion 41b at the front end portion of the fixing flange 41 becomes the packing 40. The flange portion 31b of the nozzle case 31 comes into close contact with the packing 40 in a water tight manner. As a result, the nozzle case 31 is fixedly attached to the side wall 1 a of the bathtub 1 with the fixing flange 41.

  The nozzle cover 42 is attached to the flange portion 41 b of the fixed flange 41 by screwing the female screw 42 a at the rear end portion of the cylindrical nozzle cover 42 into the male screw 41 c of the flange portion 41 b of the fixed flange 41 from the inside of the bathtub 1. become. The nozzle cover 42 has the discharge port 3 formed therein.

  As shown in detail in FIG. 8, the fixing flange 41 is formed with a plate-like closing portion 41 d that closes the outer periphery of the mesh holder 37, and inner and outer double concentric circles are set in the closing portion 41 d, A large number of through-holes 41e are formed along the inner small-diameter circle at equal angular intervals on the circumference, and are shifted by a half pitch from the inner small-diameter through-hole 41e along the outer large-diameter circle. Thus, a large number of small through holes 41e are formed at equal angular intervals on the circumference. Water-tightness can be improved by interposing a packing (not shown) between the inner peripheral surface of the blocking portion 41 d and the outer peripheral surface of the mesh holder 37.

  On the outer peripheral surface of the nozzle cover 42, as shown in FIG. 6, a plurality of the suction ports 2 are formed at equal angular intervals on the circumference. A mesh (metal mesh body ... see chain line) 43 is attached to the suction port 2 and the discharge port 3 of the nozzle cover 42.

  In the case of the discharge nozzle 30 configured as described above, as shown in FIG. 6, the hot and cold water in which the gas is dissolved flows from the outflow pipe 11 to the upstream side venturi pipe 31a of the nozzle case 31 as indicated by an arrow a. By discharging into the bath water in the bathtub 1 from the discharge port 3 of the nozzle cover 42 through 12a and the downstream venturi pipe 12b, dissolved gas precipitates in the bath water and fine bubbles are generated.

  Further, the bath water in the bathtub 1 is sucked into the nozzle case 31 from the suction port 2 of the nozzle cover 42 as shown by an arrow b, and passes through the small through hole 41e of the closing portion 41d of the fixing flange 41, as shown in FIG. As described above, the pump 6 is sucked from the connecting pipe 5 connected to the outer side of the nozzle case 31.

  In the configuration of the discharge nozzle 30 described above, since the cylindrical sound absorbing sheet 35 is held on the inner peripheral surface of the projecting portion 29b of the nozzle body 29, the rectifying action of fine eddy current on the surface of the sound absorbing sheet 35 is maintained. In addition, the noise is reduced, and in addition, the pulsation absorption and attenuation action of the sound absorbing sheet 35 effectively reduces the injection noise generated in the discharge nozzle 30, that is, the venturi tube 12b. Further, by providing the sound absorbing sheet 35 in the vicinity of the protruding portion 29b of the nozzle body 29, that is, the discharge port 12c of the venturi pipe 12b which is the injection noise source, the injection noise can be reduced more effectively. Furthermore, the sound absorbing sheet 35 and the silent mesh 26 can be incorporated into the nozzle body 29 having the venturi tube 12b to form a unit.

  Even if a plurality (16 in this example) of the venturi tubes 12b are provided in parallel, the sound absorbing sheet 35 can collectively reduce the injection noise generated in each of the venturi tubes 12b.

  Further, since the cylindrical silent mesh 36 made of a wire mesh is held on the inner peripheral surface of the sound absorbing sheet 35 by internal fitting, it is generated in the discharge nozzle 30 by the diffusion attenuation (rectification) action of pulsation by the silent mesh 36. The injection noise is further reduced. Further, since the sound absorbing sheet 35 is disposed on the back side of the silent mesh 36, the sound absorbing sheet 35 does not become a resistance to the jet liquid flow, and the sound absorbing sheet 35 is not scattered in the jet liquid flow.

  Further, in the case where the silent mesh 36 is not provided, the sound absorbing sheet 35 is formed in the rigid portion 35a in the vicinity of the discharge port 12c of the venturi tube 12b, as shown only in the upper half in FIG. 9B. Is preferred. That is, the sound-absorbing sheet 35 is usually soft and prevents the generation of fine bubbles in the vicinity of the discharge port 12c of the venturi tube 12b, but the vicinity of the discharge port 12c of the venturi tube 12b is a hard portion 35a. Thus, the generation of fine bubbles is not hindered.

It is a basic lineblock diagram of a bathtub device provided with a gas dissolution device concerning an embodiment of the present invention. It is a perspective view of the gas dissolving apparatus of FIG. 1 is a gas dissolving apparatus of FIG. 1, (a) is a cross-sectional view, (b) is a cross-sectional view taken along line II of (a). It is sectional drawing of the venturi pipe | tube of FIG. It is the perspective view which actualized the bathtub apparatus provided with the gas dissolving apparatus which concerns on embodiment of this invention. It is sectional drawing of the discharge nozzle of FIG. It is a disassembled perspective view of a nozzle body, a sound absorbing sheet, a silent mesh, and a mesh holder. It is a fixed flange, (a) is a front view, (b) is a side sectional view. It is a nozzle body, (a) is a perspective view, (b) is a side sectional view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bathtub 2 Suction port 3 Discharge port 8 Gas dissolution apparatus 12a Upstream venturi tube 12b Downstream venturi tube 12c Discharge port 29 Nozzle main body 29b Tubular protrusion 30 Discharge nozzle 31 Nozzle case 35 Sound absorbing sheet 36 Silent mesh 41 Fixed flange 42 Nozzle cover

Claims (3)

A gas-liquid dissolving fluid in which a gas is pressurized and dissolved in a liquid is released by a decompression means, and a fine bubble generator that ejects and discharges from a discharge nozzle while generating fine bubbles,
The nozzle body of the discharge nozzle is provided with a venturi tube as the pressure reducing means, and a cylindrical protrusion that protrudes in the discharge direction from the discharge port of the venturi tube is formed, and a cylindrical protrusion is formed on the inner peripheral surface of the protrusion. A fine bubble generating device , wherein a sound absorbing sheet is fitted and held, and the sound absorbing sheet is formed in a hard portion near a discharge port of a venturi tube .   2. The fine bubble generating device according to claim 1, wherein a plurality of the venturi tubes are provided in parallel. The microbubble generator according to claim 1 or 2 , wherein a cylindrical silent mesh made of a wire mesh is fitted and held on an inner peripheral surface of the sound absorbing sheet.

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