JP5632991B2 - Microbubble generator - Google Patents

Description

  The present invention relates to a fine bubble generating device, and more particularly to a fine bubble generating device capable of efficiently generating fine bubbles in water.

  In the breeding of fish, for example, freshwater fish such as ornamental fish such as guppy, or saltwater fish such as aquaculture piglets, the water in the breeding aquarium (breeding water) It is contaminated by the dissolution of excrement and the like, and polluted substances and suspended substances are included. If the pollutant or the like remains in the water, it adversely affects the domestic fish. For example, bacteria, bacteria, and the like are generated due to the decay of the pollutant and the domesticated fish becomes ill and threatens the life of the domesticated fish. Accordingly, it is necessary to replace the water containing the pollutant with new water or to periodically remove the pollutant itself from the water.

  However, when water containing pollutants and the like is exchanged for new water, it is necessary to exchange water in two-thirds or all of the rearing water tanks with new water, which is very difficult for the user. This is a work that takes time and effort.

  Therefore, as a method for removing pollutants from water, bubbles are generated in the water containing the pollutants, the pollutants are attached to the bubbles, and the bubbles with the pollutants removed are removed to efficiently remove the pollutants. Foam floating separation method to remove is adopted.

  For example, Japanese Patent Laid-Open No. 2002-273413 (Patent Document 1) includes a rotating cylinder and a discharge cylinder, at least from the stirring fin to the discharge means is located in the polluted water, and the discharge path is contaminated in the discharge cylinder. A pollutant removal apparatus characterized by communicating with the outside of water is disclosed. The rotating cylinder has a cylindrical shape, one end is connected to the drive shaft and rotated, an intake port is formed in the side surface of the drive shaft side cylinder, and the other open end forms an exhaust port. An agitation fin is provided at the end of the agitator, and the agitation fin is rotated with its rotation. Further, the discharge cylinder has a cylindrical shape, the cylinder axis is provided in the same direction as the cylinder axis of the rotating cylinder and includes the rotating cylinder, and the stirring fin side end portion provided on the rotating cylinder has a rotating cylinder that is closer to the rotating cylinder than the stirring fin. Located on the intake port side, a bubble absorbing hole is formed in the cylinder peripheral surface of the middle part of the cylinder, and a discharge path is provided on the drive shaft side of the bubble absorbing hole to communicate the inside of the cylinder with the outside of the cylinder. Is provided with a discharging means for sucking bubbles from the bubble absorbing hole side and discharging them to the outside of the cylinder.

  According to this configuration, the pollutant floating in the water tank adheres to the generated fine bubbles, and the fine bubbles are discharged from the water tank, so that the pollutant contained in the water can be efficiently discharged.

  Hereinafter, a conventional pollutant removing device, that is, a fine bubble generating device will be described in detail with reference to FIGS. 9 to 10.

  FIG. 9 is an explanatory diagram for explaining the generation state of bubbles in a conventional fine bubble generator. FIG. 10 is a diagram for explaining a rotating cylinder and a stirring fin attached to a conventional fine bubble generating device. 9 to 10 corresponds to the vertical direction of the microbubble generator according to the present invention, and the horizontal direction of FIGS. 9 to 10 corresponds to the horizontal direction of the microbubble generator according to the present invention.

  In the conventional microbubble generator 901, as shown in FIG. 9, the rotating cylinder 903 is inserted and fixed in the water tank 902 so that the vicinity of the bottom surface of the water tank 902 is submerged. The rotary cylinder 903 has a hollow cylindrical shape, and an air inlet 905 is formed on the end side fixed to the rotary shaft 904, and the other end is positioned below to form an exhaust port 906 that opens. Therefore, the intake port 905 and the exhaust port 906 of the rotary cylinder 903 communicate with each other, and the outside air sucked from the intake port 905 can be exhausted from the exhaust port 906. When the fine bubble generating device 901 is fixed to the water tank 902, the intake port 905 is located outside the water W.

  When the driving unit 907 is driven in this state to rotate the rotating cylinder 903, the stirring fin 908 attached to the rotating cylinder 903 also rotates as the rotating cylinder 903 rotates.

  As shown in FIG. 10A, the stirring fin 908 is fixed to the end of the rotary cylinder 903 on the exhaust port 906 side, and a plurality of blades 909 provided radially from the cylinder central axis of the rotary cylinder 903 are arranged in a disc shape. It is formed in a state of being sandwiched by upper and lower plates 910 made of The stirring fin 908 is rotated by rotating the rotating cylinder 903. The stirring fin 908 is provided with an upper and lower plate 910 to prevent the blade 909 from being deformed or the like with rotation, and the upper plate is formed from a donut-shaped disk that is locked only at the tip portion of each blade 909. Composed.

  When the stirring fin 908 rotates, as shown in FIG. 10B, the water W in the vicinity of the stirring fin 908 is stirred to generate a negative pressure, and the outside air (air) is rotated from the intake port 905 of the rotating cylinder 903 to the rotating cylinder. 903 is taken in, sucked into the exhaust port 906, and exhausted into the liquid.

  The air exhausted into the liquid is agitated by the agitation fins 908, becomes fine bubbles (fine bubbles B1) and relatively large bubbles B2, and is supplied into the water W. The fine bubbles B1 adhere to the pollutant in the water W and float near the stirring fins 908 without being ruptured. However, when the predetermined time elapses, the fine bubbles B1 slowly float on the upper surface of the water W.

  Further, if the bubble B2 is large, it rises with adhering contaminants, and takes in the fine bubble B1 and rises while increasing its diameter. Since the large bubbles B2 are not ruptured even when they are rising, they gather on the upper surface of the water tank at a higher rising speed than the rising speed of the fine bubbles B1. As a result, the fine bubbles B1 or large bubbles B2 attached with the pollutant are collected on the upper surface of the water tank 902, and the water W is replaced with new water by removing the collected fine bubbles B1 or large bubbles B2. Therefore, the pollutant contained in the water W can be efficiently discharged (FIG. 9, FIG. 10B).

  Further, Japanese Patent Application Laid-Open No. 2006-82072 (Patent Document 2) discloses a microbubble generator described in Patent Document 1 provided from a plate-like body that is provided outside the rotation of the stirring fin and obstructs stirring of the stirring fin. A plurality of baffle plates are erected and the upper and lower sides of the baffle plates are connected and fixed by a fixed plate to enclose the stirring fins, and a large number of holes are formed outside the radial direction (radial direction) of the included stirring fins. A fine bubble generating device comprising: a stator provided with a perforated plate, wherein gas sucked by the agitating fin is finely divided by the agitating fin, the perforated plate and the baffle plate of the stator, and supplied into the liquid Is disclosed.

  With this configuration, the gas sucked by the negative pressure becomes a larger amount of fine bubbles than the fine bubble generating device described in Patent Document 1, and relatively large bubbles are reduced by the stator. It is said that bubbles can be generated.

JP 2002-273413 A JP 2006-82072 A

  However, in the techniques described in Patent Documents 1 to 2, if the stirring fin provided in the rotating body does not rotate at a predetermined rotational speed and also at a relatively high speed, a negative pressure is applied around the stirring fin. There is a problem that it cannot be generated and fine bubbles cannot be generated. That is, the drive unit in the techniques described in Patent Documents 1 to 2 requires a very large load, and there is a problem that power consumption increases as a whole of the fine bubble generating device.

  Furthermore, in the techniques described in Patent Documents 1 to 2, air is drawn from the exhaust port using a negative pressure in water, but the negative pressure is around the stirring fin even if the rotation speed of the rotating cylinder is constant. It tends to fluctuate according to the environment. And since the drawn-in air collides with the blade | wing of a stirring fin, since the fine bubble B1 and the big bubble B2 generate | occur | produce, in addition to the fluctuation | variation of a negative pressure, the generation amount of the fine bubble B1 and the big bubble B2 ( There is a problem that it is difficult to adjust the exhaust amount of air) and it is difficult to adjust the hole diameter of the generated bubbles. Therefore, in the techniques described in Patent Documents 1 to 2, when adjusting the pore diameter of the bubbles, the size and shape of the stirring fin blade, the size of the exhaust port, etc. are appropriately changed, or the predetermined pore diameter is provided. It is necessary to install a perforated plate, and a very laborious and costly method is adopted.

  Therefore, the present invention has been made to solve the above-mentioned problems, and as a result of intensive research conducted by the present inventor, it is possible to efficiently generate fine bubbles in water based on a revolutionary idea. An object of the present invention is to provide a fine bubble generating device that can be used.

In order to solve the above-described problems and achieve the object, the microbubble generator according to the present invention includes a rotating shaft tube and a rotation of the shaft tube on an outer periphery of a body attached to a tip of the shaft tube. An impeller provided with a wing body extending from the shaft to a predetermined distance in the radial direction of the shaft tube and having a semicircular tip as viewed from the rotation direction of the shaft tube, and the impeller rotated in the liquid Sometimes, the wing body has a semicircular contact circumferential surface between the leading edge of the wing body and water, and is subjected to a hydraulic pressure fluctuation of a vortex generated downstream of the wing body in the rotation direction of the wing body. 1/3 to 1/50 of the height of the wing body with respect to the outer peripheral surface of the fuselage at a predetermined position of the fuselage at the downstream side in the rotation direction and in the vicinity of the semicircular center of the wing body. in pore size that is set in the range, supply air with outside air communicates through the cavity and the axial pipe provided on the body When, according to the rotation speed of the impeller, and means for adjusting the pore size of the fine bubbles generated in the liquid.

  The axial tube can be configured in a triangular cylindrical shape, a rectangular cylindrical shape, a polygonal cylindrical shape, or a cylindrical shape.

  Further, the body can be configured in a triangular cylindrical shape, a square cylindrical shape, a polygonal cylindrical shape, or a cylindrical shape.

  Further, the wing body whose front end in the rotation direction of the axial tube or the tip in the radial direction is a part of a circle or a sphere is formed in a shape corresponding to a circle such as a perfect circle, a substantially circle, a semicircle, an ellipse, an arc, or a curve. Is done. The wing body itself may have a spherical shape or a spherical shape close thereto. It is sufficient that the blade body has a shape close to a circle so that when the impeller is rotated in the liquid, a vortex is generated on the downstream side in the rotation direction of the blade body. Further, when the wing body is immersed in the liquid, the contact peripheral surface with water becomes a surface having an arc.

  Further, the tip of the wing body is the front surface in the rotational direction of the axial tube, or the tip in the radial direction is a part of a circle or a sphere. The fact that the wing body has an arc shape along the radial direction from the rotational axis of the fuselage. The wing body has a shape of a circle or a part of a circle when viewed from the tangential direction of the rotation direction of the fuselage, or the wing body is a circle or circle when viewed from the rotation direction of the fuselage. This corresponds to having a partial shape.

The height of the wing body is set within a range from 2/3 to 1/5 of the outer diameter of the fuselage.

Further, in the fine bubble generating device, the cross-sectional shape of the wing body viewed from the axial direction of the axial tube is a wing shape curved downstream in the rotational direction of the fuselage, and the tip of the wing body is The tip is formed along the direction opposite to the rotational direction of the fuselage as viewed from the axial direction of the axial tube, and the air supply port is formed from the tip of the wing as viewed from the rotational direction of the wing. Is opened at the position of the intersection of the straight line drawn down toward the rotation axis and the outer peripheral surface of the body.

Further, in the fine bubble generating device, the wing body inclines the outer surface on the upstream side in the rotation direction of the fuselage at a predetermined angle with respect to the direction perpendicular to the rotation direction when viewed from the axial direction of the shaft tube. And the tip of the wing body is formed in a trapezoidal shape with the outer surface on the downstream side in the rotation direction of the fuselage as viewed from the axial center direction of the shaft tube being a plane perpendicular to the rotation direction. The air supply port is formed on a surface along the rotational direction of the fuselage as viewed from the axial center direction of the shaft tube, and the air supply port is formed from the intersection of the trapezoidal vertical surface of the wing body and the outer peripheral surface of the fuselage. The opening is made at a position moved along the rotation direction by a predetermined opening distance within the height of the body.

  Moreover, the said microbubble generator can be comprised so that the said wing | blade body may consist of hollow bending piping and a cylindrical small cylinder. The bent pipe extends in the radial direction of the shaft tube, and is bent in a shape from the outer peripheral surface of the body toward the downstream side in the rotation direction of the shaft tube at a predetermined position in the radial direction of the shaft tube. Can be configured. In addition, it is possible to adopt a configuration in which a small cylinder is fitted to the distal end portion of the bent pipe, and the distal end portion of the small cylinder is cut in a substantially vertical plane with respect to the rotation direction of the axial tube. Furthermore, an elliptical opening is formed in the cut surface of the tip of the small cylinder, and the opening corresponds to an air supply port that supplies air in the cavity of the body as bubbles to the liquid. can do.

Further, the fine bubble generation device, the blade body has a cavity in communication with the body, in a semicircular shape along the direction opposite to the direction of rotation of the shaft tube as viewed from the radial direction toward the shaft tube has formed tip, before Symbol air inlet is at the downstream side in the rotational direction of said blade body, on the central line of the blade body together it is multiply provided at predetermined intervals in a row, of the body and the shaft tube The wing body communicates with the outside air through the cavity and the cavity of the wing body, and the one air supply port is located at a position near the center of the most advanced semicircular shape as viewed from the rotation direction of the wing body. it can be configured cormorants by provided in the vicinity of the center of the position of the semicircular shape of the tip as viewed from the radial direction.

  The impeller may be rotated by rotating the impeller alone or by rotating the shaft tube to which the body is connected.

  According to the fine bubble generating apparatus of the present invention, the rotational front of the axial tube or the radial distal end of the axial tube and the outer periphery of the body attached to the distal end of the axial tube is a part of a circle or a sphere. An impeller provided with a wing body, a cavity provided in a predetermined position of the impeller, and an air supply port communicating with the outside air via a shaft tube are provided.

  This makes it possible to easily generate vortices (Karman vortices) from the wing body, and to supply fine bubbles into the liquid from the air supply port due to periodic water pressure fluctuations of the generated vortices. . The cycle of the vortex water pressure fluctuation can be easily changed by changing the rotation speed of the impeller, so the rotation speed of the impeller is adjusted to adjust the cycle of the vortex water pressure fluctuation and It is possible to change the size of the pore diameter of the fine bubbles supplied to the.

  Moreover, since the function (for example, pollutant removal function, dissolved oxygen supply function, etc.) possessed by the microbubbles differs depending on the size of the microbubbles, for example, when seawater fish is bred in an aquaculture tank, By changing the size of the fish, it is possible to appropriately adjust the breeding environment of the saltwater fish according to the growth situation of the saltwater fish bred in the aquarium.

  Furthermore, since it is possible to reliably generate fine bubbles simply by rotating the wing body, it is possible to reduce the load on the driving unit required to rotate the impeller, and the power consumption of the entire fine bubble generating device This makes it possible to efficiently generate fine bubbles.

  Further, it is more preferable that the predetermined position is a position that receives a water pressure fluctuation generated downstream in the rotation direction of the blade body when the impeller rotates in the liquid.

  Further, it is possible to adopt a configuration in which the wing body is extended to a predetermined radial distance from the rotating shaft of the axial tube, and the air supply port has a hole diameter corresponding to the predetermined distance.

  Thus, the rotational torque of the wing body is determined by the predetermined distance of the wing body, and the fluctuation of the vortex water pressure generated from the wing body is determined by the magnitude of the rotation torque. By setting the hole diameter of the air port, it is possible to appropriately balance the fluctuation of the vortex water pressure and the amount of air bubbles supplied from the air supply port, and efficiently generate air bubbles from the air supply port.

  Further, the wing body is formed in a semicircular shape at the front or radial front end of the axial tube, and the air supply port is formed in a semicircular shape on the downstream side in the rotation direction of the wing body. The structure provided in the position near the center of can be employed.

  Thereby, it becomes possible to concentrate the vortex generated from the wing body, which is a contact peripheral surface with water, to the air supply port, and to efficiently supply fine bubbles from the air supply port.

It is the schematic of the fine bubble generator which concerns on 1st embodiment of this invention. It is a schematic structure figure showing an impeller concerning a first embodiment of the present invention. It is a schematic block diagram which shows the impeller which concerns on 2nd embodiment of this invention. It is a schematic block diagram which shows the impeller which concerns on 3rd embodiment of this invention. It is a schematic block diagram which shows the impeller which concerns on 4th embodiment of this invention. It is a schematic block diagram which shows the impeller which concerns on 5th embodiment of this invention. It is a schematic diagram of the microbubble generator concerning the present invention. It is front sectional drawing of the downward structure of the microbubble generator which concerns on this invention. It is explanatory drawing explaining the generation | occurrence | production state of the bubble of the conventional fine bubble generator. It is a figure explaining the rotation cylinder attached to the conventional fine bubble generator, and a stirring fin.

  Hereinafter, with reference to the accompanying drawings, an embodiment of the fine bubble generating apparatus of the present invention will be described for the understanding of the present invention. In addition, the following embodiment is an example which actualized this invention, Comprising: The thing of the character which limits the technical scope of this invention is not.

<First embodiment>
FIG. 1 is a schematic view of a fine bubble generator 1 according to a first embodiment of the present invention. However, details of each part not directly related to the present invention are omitted. FIG. 1A is a front sectional view of the fine bubble generating device 1 according to the first embodiment, and FIG. 1B is an underwater view of the impeller of the fine bubble generating device 1 according to the first embodiment. It is a front view sectional view showing the state where it was immersed in and rotated. The vertical direction in FIG. 1 corresponds to the vertical direction of the fine bubble generator 1 according to the present invention, and the horizontal direction in FIG. 1 corresponds to the horizontal direction of the fine bubble generator 1 according to the present invention.

  As shown in FIG. 1 (A), the fine bubble generating device 1 includes a cavity communicating with the shaft tube 10 at the lower end 10a of the cylindrical shaft tube 10 and an air supply port described below. 14 is provided with a body 11a (rotary body, rotating cylinder) for introducing air, and four wing bodies 12 are provided radially on the outer peripheral surface of the body 11a to constitute an impeller 11 (impeller).

  The shaft tube 10 transmits a rotational force to the impeller 11 and supplies air to the cavity of the body 11a through an intake port 13 provided at an upper end of the shaft tube 10.

  The body 11a is formed in a cylindrical shape having an outer diameter larger than the outer diameter of the shaft tube 10, and communicates with the outside air through the shaft tube 10 (a cavity of the shaft tube).

  Further, in the wing body 12, the front end 12a in the rotational direction of the axial tube 10 is formed in a semicircular shape, and the front end in the rotational direction of the axial tube 10 (not shown) is formed in a semicircular shape. The wing body 12 is formed to extend from the rotating shaft 11b of the shaft tube 10 to a predetermined distance t in the radial direction. The predetermined distance t corresponds to a value obtained by adding the height h of the wing body 12 with respect to the outer peripheral surface 11c of the body 11a and the outer diameter R of the body 11a.

  As shown in FIG. 1B, when the impeller 11 configured in this manner is immersed in water in the water tank and rotated, fine bubbles are generated as follows.

  First, when the impeller 11 is immersed in water, the contact front surface with the water of the front end 12a in the rotation direction of the wing body 12 extended to the impeller 11 has a semicircular shape. In this state, when the shaft tube 10 is rotated by a drive unit (not shown), the entire impeller 11 rotates along the rotation shaft 11 b of the shaft tube 10, and the impeller 11 applied to the tip of the wing body 12 is rotated. The rotational torque is maximized. As shown in FIG. 1B, a vortex (Kalman vortex) is generated behind the wing body 12 as the impeller 11 rotates. An air supply port 14 is opened at a position of the outer peripheral surface 11c of the body 11a that receives fluctuations in the generated vortex water pressure, and communicates with the outside air through the air inlet 13 of the shaft tube 10, the cavity of the shaft tube 10, and the cavity of the body 11a. Then, the fine bubbles B1 are supplied into the liquid.

  The fine bubble B1 rises while adhering pollutants floating in the water in the water tank, and rises as a large bubble B2 by increasing the diameter while taking in and combining other fine bubbles B1. Become.

  In the above description, the rotation shaft 11b of the shaft tube 10 and the body 11a is made to coincide with each other, and the impeller 11 (body 11a) is rotated by the rotation of the shaft tube 10. However, other configurations may be used. For example, a drive unit may be provided in the impeller 11 so that the impeller 11 is rotated alone. In that case, the rotating shaft 11b of the shaft tube 10 described above is different from the rotating shaft of the body 11a.

  Next, the structure of the impeller 11 according to the first embodiment will be described in detail.

  FIG. 2 is a schematic configuration diagram showing the impeller 11 according to the first embodiment of the present invention. FIG. 2A is a front view of the impeller 11 according to the first embodiment. FIG. 2B is a plan view of the impeller 11 according to the first embodiment. FIG. 2C is a plan view end view taken along the line AA shown in FIG. FIG. 2D is a front view end view taken along line BB shown in FIG.

  In the impeller 11 according to the first embodiment, as shown in FIGS. 2 (A) to 2 (B), the wing body 12 has a predetermined height h on the side surface of the cylindrical body 11a. Four radially extend from the outer peripheral surface 11c of the body 11a. Further, the four wing bodies 12 are arranged at equal intervals in the circumferential direction of the body 11a.

  The front end 12a in front view of the wing body 12 is formed in a semicircular arc shape along the radial direction (left-right direction) from the rotating shaft 11b of the body 11a in front view, and has a semicircular shape as a whole. Furthermore, the planar view outer edge 12b of the wing body 12 is formed in an arc shape along the rotation direction of the body 11a in the plan view, and constitutes a wing shape as a whole. The front end 12a of the wing body 12 as viewed from the front is formed in a shape that is pointed along the direction opposite to the rotational direction of the body 11a. In the first embodiment, the planar view outer edge 12b of the wing body 12 corresponds to the distal end of the wing body 12 in plan view.

  Further, the air supply port 14 for supplying air into the liquid as air bubbles inside the body 11a (cylindrical cavity) is positioned at the downstream side (rear side) of the wing body 12 in the rotational direction. Is open to.

  Next, the shape of one wing body 12 in plan view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 2 (C), the plane view sectional shape of one wing body 12 is a wing shape curved to the downstream side in the rotation direction of the fuselage 11a, and as described above, the wing body 12 is viewed from the front. The tip 12a is formed to be sharp along the direction opposite to the rotation direction of the body 11a in plan view.

  The outer edge 12b in plan view of the wing body 12 is formed in an arc that draws a smooth curve along the rotational direction of the body 11a. Specifically, as shown in FIG. 2 (C), the planar view outer edge 12b of the wing body 12 extends from the front end 12a of the wing body 12 when viewed from the front, and the rotation shaft 11b of the fuselage 11a (the center of the fuselage 11a). An arc having a radius r1 between the front end 12a of the wing body 12 and the intersection 1222 is drawn centering on the intersection 1222 between the straight line 1221 and the outer peripheral surface 11c of the body 11a. It is formed into a shape. The radius r1 corresponds to the height h of the wing body 12 with respect to the outer peripheral surface 11c of the body 11a. When the wing body 12 in the plan view has the above-described shape, when the body 11a is rotated, the rotational torque of the impeller 11 applied to the front end 12a of the wing body 12 when viewed from the front is maximized.

  The radius r1 of the circular arc shape of the outer edge 12b in plan view of the wing body 12, in other words, the height h of the wing body 12 is set within a range from 2/3 to 1/5 of the outer diameter R of the fuselage 11a. It is preferable that it is within a range from one third to one fourth. When the height h of the wing body 12 is within a predetermined range, a vortex (Karman vortex) can be easily generated from the front end 12a of the rotated wing body 12 and the wing body 12 It becomes possible to reduce the water pressure received from the water W.

  The height h of the wing body 12 shown in FIG. 2C is 15 mm, the outer diameter R of the fuselage 11a is 30 mm, and the inner diameter is 25 mm.

  The air supply port 14 provided in the body 11a is opened at the position of the intersection 1222 between the straight line 1221 and the outer peripheral surface 11c of the body 11a. When the air supply port 14 is opened at the position, the vortex 1223 generated from the front end 12a of the rotated wing body 12 makes contact with the upper surface of the air supply port 14 while turning. Then, the air supply port 14 is subjected to the water pressure fluctuation of the vortex 1223.

  In addition, as long as it is a position which receives the water pressure fluctuation of the vortex 1223, the position where the air supply port 14 is opened may be any position. For example, if the shape of the wing body 12 is the wing shape described above, the air supply port 14 is moved from the intersection 1222 toward the wing body 12 by a predetermined opening distance d1 on the downstream side in the rotation direction of the wing body 12. It can be opened at the position. The predetermined opening distance d1 is appropriately changed in design according to the rotational speed of the impeller 11, the outer diameter R of the fuselage 11a, the height h of the wing body 12, the shape of the wing body 12, and the like.

  Moreover, it is preferable that the hole diameter of the air supply port 14 is set within a range from 1/3 to 1/50 of the height h of the wing body 12, and a range from 1/5 to 1/25. It is more preferable that it is within the range of 1/10 to 1/8, and even more preferable. When the hole diameter of the air supply port 14 is within a predetermined range, the water pressure fluctuation of the vortex 1223 generated from the blade body 12 and the amount of air supplied from the air supply port 14 due to the water pressure fluctuation are appropriately balanced. In addition, it is possible to efficiently supply air into the liquid from the air supply port 14 as bubbles. The hole diameter of the air supply port 14 shown in FIG. 2C is 1 mm, and the height h of the wing body 12 is 15 mm.

  Next, the shape of one wing body 12 in a front view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 2D, the front end 12a of one wing body 12 is formed in a semicircular shape along the radial direction from the rotating shaft 11b of the body 11a (not shown). The semicircular radius of the front end 12a of the wing body 12 coincides with the arc-shaped radius r1 of the outer edge 12b in plan view of the wing body 12, that is, the height h of the wing body 12. That is, the shape of the wing body 12 corresponds to the shape of a quarter of a sphere as a whole. Further, the front end 12 a of the wing body 12 when viewed from the front is formed in a sharp shape in the direction opposite to the rotation direction of the wing body 12.

  Further, the air supply port 14 is opened at the position of the semicircular center 1224 of the front end 12 a of the wing body 12 on the downstream side in the rotation direction of the wing body 12. When the air supply opening 14 is opened at the position, the vortex 1223 generated from the front end 12a of the wing body 12 is concentrated at the position of the center 1224 of the semicircular shape. It will surely receive periodic water pressure fluctuations.

  Next, the operation of the first embodiment of the present invention will be described.

  As shown in FIGS. 1 and 2, when the impeller 11 is rotated by driving the drive unit in a state where the blade body 12 is submerged, the microbubble generator 1 has four blades as the impeller 11 rotates. The body 12 also rotates. When the wing body 12 rotates, a vortex 1223 is generated on the downstream side in the rotation direction of the wing body 12 from the front end 12a of the wing body 12 when viewed from the front. The generated vortex 1223 turns and contacts the upper surface of the air supply port 14, and due to the contact of the vortex 1223, near the upper surface of the air supply port 14, the water pressure fluctuation of the vortex 1223 is constantly received.

  When one vortex 1223 passes through the upper surface of the air supply port 14, the water pressure near the upper surface of the air supply port 14 rises, but when the vortex 1223 finishes passing through the upper surface of the air supply port 14, the air supply port The water pressure near the upper surface of 14 drops significantly. Due to the lowering of the water pressure, a negative pressure is generated in the vicinity of the upper surface of the air supply port 14, and the air in the air supply port 14 is drawn into the liquid. Thereby, the air supply port 14 supplies (supplies) the air in the impeller 11 to the liquid as bubbles. The air drawn into the liquid is crushed by the fluctuation of the water pressure of the vortex 1223 and the collision with the wing body 12, and is diffused around the impeller 11 as fine bubbles B1 and floats.

  When the impeller 11 is steadily rotated, the vicinity of the upper surface of the air inlet 14 is subjected to periodic water pressure fluctuations due to the vortex 1223 generated from the blade body 12. Therefore, the air supply port 14 periodically supplies a predetermined amount of air into the liquid. Although the air to be supplied diffuses around the impeller 11 as fine bubbles B1, the hole diameter of the fine bubbles B1 at the time of crushing is determined by the degree of crushing described above, and according to the hole diameter of the fine bubbles B1, The fine bubbles B1 exist alone, or the fine bubbles B1 are combined to form a large bubble B2.

  The degree of the air crushing can be adjusted by changing the cycle of the water pressure fluctuation of the vortex 1223. The period of the water pressure fluctuation of the vortex 1223 can be easily changed according to the rotational speed of the impeller 11, the outer diameter R of the fuselage 11a, the height h of the wing body 12, the shape of the wing body 12, and the like.

  For example, if the shape of the wing body 12 is the above-described shape, the outer diameter R of the fuselage 11a and the height h of the wing body 12 are constant, and the rotation speed of the impeller 11 is increased, the water pressure fluctuation of the vortex 1223 is changed. Since the cycle is shortened, the degree of air crushing becomes remarkable due to the fluctuation of the water pressure of the vortex 1223 having a short cycle, and naturally, a large amount of fine bubbles B1 having a small pore diameter are generated.

  On the other hand, if the shape of the wing body 12 is the above-described shape, the outer diameter R of the fuselage 11a and the height h of the wing body 12 are constant, and the rotational speed of the impeller 11 is reduced, the water pressure fluctuation of the vortex 1223 is reduced. Since the cycle becomes long, the degree of air crushing is mitigated by the fluctuation of the water pressure of the vortex 1223 having a long cycle, and fine bubbles B1 having a large pore diameter are generated.

  Therefore, by appropriately changing the rotation speed of the impeller 11, it is possible to change the period of the water pressure fluctuation of the vortex 1223 and easily change the hole diameter of the fine bubbles B1 supplied into the liquid.

  The range of the hole diameter of the fine bubbles B1 described above includes the hole diameter of the air supply port 14 that defines the air supply amount, the rotational speed of the impeller 11, the outer diameter R of the fuselage 11a, the height h of the wing body 12, and the wing body 12. It fluctuates according to the shape etc.

  For example, if the hole diameter of the air inlet 14 is 1 mm, the outer diameter R of the fuselage 11a is 30 mm, the height h of the wing body 12 is 15 mm, and the rotation speed of the impeller 11 is set to 500 rpm, the fine generated around the impeller 11 The average pore diameter of the bubbles B1 is in the range of 1 cm to 1 μm. When the rotation speed of the impeller 11 is set to 1000 rpm, the average pore diameter of the fine bubbles B1 generated around the impeller 11 is in the range of 50 mm to 1 nm. Furthermore, when the rotation speed of the impeller 11 is set to 2500 rpm, the average pore diameter of the fine bubbles B1 generated around the impeller 11 is in the range of 20 mm to 1 nm.

  When employ | adopting the microbubble generator which concerns on this invention for a breeding tank, it is preferable that the rotation speed of the impeller 11 is the range of 1500-2000 rpm.

  The generated fine bubbles B1 have different functions (actions) for water depending on the size of the pore diameter. For example, if the average pore diameter is 1 cm to 1 mm, the fine bubbles B1 are easily combined with each other to form a large bubble B2 and float on the upper surface of the water tank. Since such bubbles rise while adhering pollutants in the water, they function to remove the pollutants contained in the water in the water tank.

  Furthermore, if the average pore diameter is 1 cm to 1 mm, the fine bubbles B1 float on the surface of the water while absorbing (adsorbing) the ammonia content (ammonia, nitrogen compounds, etc.) contained in the water, so that they are released from the surface of the domestic fish. It also functions to remove ammonia that can threaten the life of the fish.

  For example, when the average pore diameter is 1 mm to 1 μm, the fine bubbles B1 do not immediately float on the upper surface of the water tank, and float around the impeller 11 for a while. Since the generated fine bubbles B1 naturally contain oxygen, it functions to raise the dissolved oxygen in the water W. However, in the fine bubbles B1 having an average pore diameter of 1 mm to 1 μm, when they collide with other fine bubbles B1, they become large bubbles B2. Therefore, after a predetermined time elapses, the fine bubbles B1 are combined to float on the upper surface of the water tank while increasing the pore diameter, and function to remove the above-mentioned contaminants.

  On the other hand, for example, if the average pore diameter is 1 μm to 1 nm, minute ions (sodium ions, potassium ions, etc.) in water may surround the fine bubbles B1 and stabilize the fine bubbles B1. Since the stabilized fine bubbles B1 naturally contain oxygen, the dissolved oxygen in the water is raised for a long period of time. Furthermore, the stabilized microbubbles B1 will collapse when they come into contact with bacteria, bacteria, etc. that survive in the water, but the bacteria, etc. are killed by the collapsed impact. That is, the stabilized fine bubbles B1 having an average pore diameter of 1 μm to 1 nm function to sterilize water.

  The above-described plurality of functions of the fine bubbles B1 can be easily used properly by changing the average pore size of the fine bubbles B1.

  For example, in an aquarium that breeds marine fish such as aquaculture pigs, the size of feces and other pollutants discharged from the juvenile fish to adult fish, The amount of oxygen and the amount of bacteria that propagate in the aquarium vary greatly.

  If the microbubble generator according to the first embodiment of the present invention is employed in the water tank, the average pore diameter of the generated microbubbles B1 can be easily changed simply by changing the rotational speed of the impeller 11. Depending on the growth status of the seawater fish in the aquarium, it is possible to selectively use a plurality of functions of the fine bubbles. Therefore, it is possible to easily provide an optimal environment for the saltwater fish by changing the environment of the saltwater fish so that the saltwater fish changes from the fry to the adult fish so as to correspond to the growth stage.

  As another application, for example, the microbubble generator according to the first embodiment of the present invention can be employed in a treatment tank for nitrogen-containing wastewater. In the treatment tank, microorganisms that capture nitrogen are immobilized on a predetermined carrier (culture material or the like), but the microorganisms are greatly activated under predetermined dissolved oxygen. If microbubbles are generated in the wastewater in the treatment tank using the microbubble generator, the amount of nitrogen captured is increased due to the activation of microorganisms, resulting in efficient treatment of nitrogen-containing wastewater. It becomes possible to do.

  Further, the fine bubble generating device 1 according to the first embodiment of the present invention has a wing body having a very small area with respect to the front surface in the rotation direction of the impeller (a surface perpendicular to the rotation direction and a vertical surface in the rotation direction). It is possible to generate the fine bubbles B1 simply by rotating them.

  Conventionally, although the negative pressure is generated by rotating the blades of the stirring fin at a high speed, the blades have a very large area with respect to the front surface in the rotation direction. Therefore, the water pressure that the blade receives is extremely large. Then, the power consumption of the drive unit required for high-speed rotation of the stirring fins (blades) becomes very large.

  On the other hand, in the microbubble generator 1 according to the first embodiment of the present invention, since the area of the wing body with respect to the front surface in the rotational direction is narrower than the conventional blade, the water pressure received by the wing body is extremely small. Become. Therefore, the power consumption of the fine bubble generating device 1 according to the first embodiment is less than one tenth of the power consumption of the conventional fine bubble generating device using the stirring fin.

  As described above, according to the fine bubble generating device 1 of the present invention, the axial tube 10 and the outer periphery 11c of the body 11a attached to the tip 10a of the axial tube 10 are arranged on the front surface or the diameter of the axial tube 10 in the rotational direction. An impeller 11 provided with a wing body 12 whose tip in the direction is a part of a circle or a sphere, provided at a predetermined position of the impeller 11, and communicated with outside air via a cavity and a shaft tube 10 provided in the body 11a. The air supply port 14 is configured to be provided.

  As a result, the vortex 1223 can be easily generated from the wing body 12 and the fine bubbles can be supplied into the liquid from the air supply port 14 by the periodic water pressure fluctuation of the generated vortex 1223. . Since the cycle of the water pressure fluctuation of the vortex 1223 can be easily changed by changing the rotation speed of the impeller 11, the rotation speed of the impeller 11 is adjusted to adjust the water pressure fluctuation period of the vortex 1223. In addition, the pore size of the fine bubbles supplied in the liquid can be changed.

  Moreover, since the function (for example, pollutant removal function, dissolved oxygen supply function, etc.) possessed by the microbubbles differs depending on the size of the microbubbles, for example, when seawater fish is bred in an aquaculture tank, By changing the size of the fish, it is possible to appropriately adjust the breeding environment of the saltwater fish according to the growth situation of the saltwater fish bred in the aquarium.

  Furthermore, since it is possible to reliably generate fine bubbles simply by rotating the wing body 12, it is possible to reduce the load on the driving unit required to rotate the impeller 12, and the fine bubble generator 1 as a whole. It is possible to efficiently generate fine bubbles while suppressing the power consumption.

  More preferably, the predetermined position at which the air supply opening 14 is opened is a position that receives a fluctuation in water pressure generated on the downstream side in the rotation direction of the blade body 12 when the impeller 11 rotates in the liquid.

  Further, the air supply port 14 can be configured to have a hole diameter corresponding to the predetermined distance t.

  Thereby, the rotational torque of the wing body 12 is determined by the predetermined distance t of the wing body 12, and the fluctuation of the water pressure of the vortex 1223 generated from the wing body 12 is determined by the magnitude of the rotational torque. By setting the hole diameter of the air supply port 14 corresponding to the water pressure fluctuation, the water pressure fluctuation of the vortex 1223 and the amount of bubbles supplied from the air supply port 14 are appropriately balanced, and bubbles can be efficiently discharged from the air supply port 14. Can be generated.

  In addition, the wing body 12 is formed in a semicircular shape at the front surface or the radial tip of the axial tube 10, and the air supply port 14 is downstream of the wing body 12 in the rotation direction. It can be configured to be provided in the vicinity of the center of the 12 semicircular shapes.

  This makes it possible to concentrate the vortex generated from the front end 12a of the wing body 12 that is a contact surface with water on the air supply port 14, and efficiently supply fine bubbles from the air supply port 14. It becomes possible to make it.

  The blade body 12 has a front end 12a in the rotational direction of the axial tube 10 formed in a semicircular shape, and a radial end 12c of the axial tube 10 formed in a semicircular shape, and the air supply port 14 However, it can be configured to be provided at a position near the semicircular center of the radial tip of the axial tube 10 on the downstream side in the rotational direction of the wing body 12.

  Accordingly, the vortex 1223 can be generated more efficiently, and the water pressure received by the wing body 12 is reduced, so that the power consumption of the fine bubble generating device 1 can be reduced.

<Second Embodiment>
Next, the fine bubble generator of the second embodiment will be described with reference to FIG. FIG. 3 is a schematic configuration diagram illustrating the impeller 11 according to the second embodiment. In addition, the detail of each part which is not directly related to 2nd embodiment of this invention is abbreviate | omitted.

  Compared with the first embodiment, the difference of the second embodiment is that the shape of the wing body 12 is changed and the position of the air supply port 14 is changed. Since the other points are the same as those in the first embodiment, details of each part not directly related to the second embodiment are omitted. Also, description of the same reference numerals as those in the first embodiment is omitted.

  FIG. 3A is a front view of the impeller 11 according to the second embodiment. FIG. 3B is a plan view of the impeller 11 according to the second embodiment. FIG. 3C is a cross-sectional view in plan view along the line AA shown in FIG. FIG. 3D is a front view cross-sectional view along the line BB shown in FIG.

  In the impeller 11 according to the second embodiment, as shown in FIGS. 3A to 3B, the wing body 12 has a predetermined height h on the side surface of the cylindrical body 11 a and the impeller. Four are radially extended from the outer peripheral surface 11c of 11. The four wing bodies 12 are arranged at equal intervals in the circumferential direction of the impeller 11.

  The front end 12a of the wing body 12 is formed in a semicircular arc shape along the radial direction (left-right direction) from the rotating shaft 11b of the body 11a in front view. Further, the wing body 12 has an outer surface on the upstream side (front side) in the rotation direction of the body 11a in a plan view with a predetermined angle with respect to the front surface in the rotation direction (a direction perpendicular to the rotation direction and a vertical line in the rotation direction). The trapezoid is formed in a trapezoidal shape with the outer surface on the downstream side (rear side) in the rotational direction of the body 11a being substantially perpendicular to the rotational direction. The front end 12b in plan view of the wing body 12 is formed on a substantially parallel surface along the rotational direction of the body 11a in plan view.

  An air supply port 14 for supplying air into the liquid as air bubbles inside the body 11a is opened to each of the four wing bodies at a position downstream of the wing body 12 in the rotational direction.

  Next, the shape of one wing body 12 in plan view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 3C, the plane view sectional shape of one wing body 12 is formed in a trapezoidal shape, and as described above, the outer surface 1231 on the upstream side of the wing body 12 in the rotational direction of the fuselage 11a. Is a surface inclined at a predetermined angle α (acute angle) with respect to the normal 1232 of the outer peripheral surface 11c of the body 11a. Further, the outer surface 1233 of the wing body 12 on the downstream side in the rotational direction of the fuselage 11a is a surface substantially parallel to the normal direction of the outer peripheral surface 11c of the fuselage 11a.

  Further, the upper side of the trapezoidal shape corresponding to the front end 12c in plan view of the wing body 12 is substantially parallel to the outer peripheral surface 11c of the body 11a. The length of the upper side of the trapezoidal shape in the rotation direction is preferably in a range from one half to one fifth with respect to the length of the trapezoidal base 12l in the rotation direction. The length in the rotational direction of the trapezoidal upper side (the tip 12c in plan view of the wing body 12) shown in FIG. 3C is one third of the length of the trapezoidal base 1234 in the rotational direction.

  The vertical distance between the upper side 12k and the bottom side 1234 of the trapezoidal shape corresponds to a predetermined height h from the outer peripheral surface 11c of the body 11a, that is, the height h of the wing body 12. When the wing body 12 in the plan view has the shape described above, when the body 11a is rotated, the rotational torque of the impeller 11 applied to the front-view tip 12c of the wing body 12 and the front-view tip 12a downstream is maximized. Become.

  The height h of the wing body 12 is preferably set within a range of 2/3 to 1/5 of the outer diameter R of the fuselage 11a, and further, a range of 1/3 to 1/4. It is preferable to be within. The height h of the wing body 12 shown in FIG. 3C is 15 mm, the outer diameter R of the fuselage 11a is 30 mm, and the inner diameter is 25 mm.

  The air supply port 14 provided in the fuselage 11a is rotated by a predetermined opening distance d2 from the intersection 1235 between the trapezoidal substantially vertical surface 1233 and the outer peripheral surface 11c of the fuselage 11a on the downstream side in the rotation direction of the wing 12. It is opened at a position moved along the direction. The predetermined opening distance d2 from the intersection 1235 may be any distance as long as it is within the height h of the wing body 12, but the predetermined opening distance d2 shown in FIG. This corresponds to a length of one third of the height h of the body 12. When the air supply port 14 is opened at the position, the vortex 1223 generated from the front end 12 a of the wing body 12 turns and contacts the upper surface of the air supply port 14, and the air supply port 14 is periodically rotated by the vortex 1223. It will be subject to various water pressure fluctuation.

  Moreover, it is preferable that the hole diameter of the air supply port 14 is set within a range from 1/3 to 1/50 of the height h of the wing body 12, and a range from 1/5 to 1/25. It is more preferable that it is within the range of 1/10 to 1/8, and even more preferable. The hole diameter of the air supply port 14 shown in FIG. 3C is 1 mm, and the height h of the wing body 12 is 15 mm.

  Next, the shape of one wing body 12 in a front view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 3D, the front-view tip 12a of one wing body 12 is formed in a semicircular shape along the radial direction from the rotation shaft 11b of the body 11a (not shown). The radius of the semicircular shape of the front end tip 12a coincides with the height h of the wing body 12. Further, the front end 12a of the wing body 12 corresponds to the rear end of the front end 12c of the wing body 12 in the rotation direction, and a vortex 1223 is generated from the front end 12a.

  Further, the air supply port 14 is opened at the position of the semicircular center 1224 of the front end 12 a of the wing body 12 on the downstream side in the rotation direction of the wing body 12. When the air supply opening 14 is opened at the position, the vortex 1223 generated from the front end 12a of the wing body 12 is concentrated at the position of the center 1224 of the semicircular shape. It will surely receive periodic water pressure fluctuations.

  Thus, even if the shape of the wing body 12 and the position of the air supply port 14 described above are employed, the vortex 1223 can be easily generated. Further, since the cycle of the water pressure fluctuation of the vortex 1223 can be easily changed only by changing the rotation speed of the impeller 11, the above-described operational effects of the present invention can be obtained.

<Third embodiment>
Next, the fine bubble generator of the third embodiment will be described with reference to FIG. FIG. 4 is a schematic configuration diagram illustrating the impeller 11 according to the third embodiment. In addition, the detail of each part which is not directly related to 3rd embodiment of this invention is abbreviate | omitted.

  Compared with the first embodiment, the third embodiment is different in that the shape of the wing body 12 is changed and the position of the air supply port 14 is changed. Since the other points are the same as those in the first embodiment, details of each part not directly related to the third embodiment are omitted. Also, description of the same reference numerals as those in the first embodiment is omitted.

  FIG. 4A is a front view of the impeller 11 according to the third embodiment. FIG. 4B is a plan view of the impeller 11 according to the third embodiment. FIG. 4C is a cross-sectional view in plan view along the line AA shown in FIG. FIG. 4D is a front sectional view taken along line BB shown in FIG.

  In the impeller 11 according to the third embodiment, as shown in FIGS. 4A to 5B, the wing body 12 has a predetermined height h on the side surface 11 c of the body 11 a having a cylindrical shape. Four radially extend from the outer peripheral surface of the body 11a. The four wing bodies 12 are arranged at equal intervals in the circumferential direction of the impeller 11.

  The wing body 12 is hollow, and the front end 12a of the wing body 12 is formed in a semicircular arc shape along the radial direction (left-right direction) from the rotating shaft 11b of the body 11a in front view. . Further, the wing body 12 is formed in a shape extending to the trunk length in a front view. Furthermore, the radial tip 12d of the wing body 12 is formed in a shape that is pointed along the radial direction (extending direction of the wing body 12, radial direction of the fuselage 11a) from the rotation axis of the fuselage 11a in plan view. Is done. The wing body 12 is formed in a shape having a flat surface by crushing the front end vicinity 12e of the main body in the rotational direction of the body 11a in a front view.

  An air supply port 14 for supplying air into the liquid as air bubbles inside the fuselage 11a is opened to each of the four wing bodies at a position downstream of the wing body 12 in the rotation direction.

  Next, the shape of one wing body 12 in plan view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 4C, the planar sectional shape of one wing body 12 is a shape obtained by crushing and flattening the tip vicinity 12e inside the wing body 12. A radial tip 12d of the wing body 12 is pointed along the extending direction of the wing body 12, and corresponds to a part of the front tip 12a of the wing body 12 in front view. When the wing body 12 rotates, a vortex 1223 is generated from the front-view tip 12a of the wing body 12, and the rotation of the impeller 11 applied to the radial tip 12d of the wing body 12 which is a part of the front-view tip 12a. Since the torque becomes maximum, a large vortex 1223 is generated from the tip 12d. Here, a predetermined distance from the radial tip 12d of the wing body 12 to the outer peripheral surface 11c of the fuselage 11a corresponds to the height h of the wing body.

  The height h of the wing body 12 is preferably set within a range of 2/3 to 1/5 of the outer diameter R of the fuselage 11a, and further, a range of 1/3 to 1/4. It is preferable to be within. The height h of the wing body 12 shown in FIG. 4C is 15 mm, the outer diameter R of the fuselage 11a is 30 mm, and the inner diameter is 25 mm.

  The inside of the wing body 12 and the inside of the fuselage 11 a are configured to communicate with each other through a small pipe 15. The small pipe 15 has a cylindrical shape and is inserted from the outer peripheral surface 11c of the body 11a toward the rotation shaft 11b of the body 11a (the center of the body 11a). The upper end 15a of the small pipe 15 on the outer peripheral surface 11c side of the fuselage 11a is fitted with the lower end 15b of the wing 12 to fix the wing 12 and the fuselage 11a. Even if air is supplied from the air supply port 14 of the wing body 12 by the small pipe 15, the air inside the fuselage 11 a is supplied into the wing body 12 through the small pipe 15.

  Further, the air supply port 14 provided in the wing body 12 is moved downstream of the wing body 12 in the rotational direction and moved to the rotating shaft 11b side of the body 11a from the foremost end of the wing body 12 by a predetermined opening distance d3. An opening is made at the position of the flat surface 1251 of the wing body 12. The predetermined opening distance d3 from the tip 12d may be any distance as long as it is on the flat surface 1251 on the downstream side in the rotation direction of the blade body 12, but the predetermined distance shown in FIG. The opening distance d3 corresponds to a length of 1/5 of the height h of the wing body 12. When the air supply port 14 is opened at this position, the vortex 1223 generated from the tip 12d of the wing body 12 makes contact with the upper surface of the air supply port 14 while turning, and the air supply port 14 is periodic with the vortex 1223. It will be subject to water pressure fluctuation.

  Moreover, it is preferable that the hole diameter of the air supply port 14 is set within a range from 1/3 to 1/50 of the height h of the wing body 12, and a range from 1/5 to 1/25. It is more preferable that it is within the range of 1/10 to 1/8, and even more preferable. The hole diameter of the air supply port 14 shown in FIG. 4C is 1 mm, and the height h of the wing body 12 is 15 mm.

  Next, the shape of one wing body 12 in a front view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 4 (D), the front end 12a of one wing body 12 is formed in a semicircular shape along the radial direction from the rotating shaft 11b of the body 11a (not shown), and the main body is formed in a body length shape. Has been. The semicircular radius of the front-view tip 12a coincides with the predetermined distance d3 related to the opening position of the air supply port 14 described above.

  Further, the air supply port 14 is opened at the position of the semicircular center 1224 of the front end 12 a of the wing body 12 on the downstream side in the rotation direction of the wing body 12. When the air supply opening 14 is opened at the position, the vortex 1223 generated from the front end 12a of the wing body 12 is concentrated at the position of the center 1224 of the semicircular shape. It will surely receive periodic water pressure fluctuations. The air supply port 14 communicates with the outside air through the wing body 12, the body 11 a, and the shaft tube 10 to supply bubbles into the liquid.

  Thus, even if the shape of the wing body 12 and the position of the air supply port 14 described above are employed, the vortex 1223 can be easily generated. Further, since the cycle of the water pressure fluctuation of the vortex 1223 can be easily changed only by changing the rotation speed of the impeller 11, the above-described operational effects of the present invention can be obtained.

  Moreover, since the wing body 12 according to the third embodiment has a smaller area with respect to the front surface in the rotational direction than the wing body 12 according to the first embodiment, the water pressure received by the wing body 12 can be further reduced. It becomes possible. As a result, the power consumption of the microbubble generator 1 according to the third embodiment is further reduced.

<Fourth embodiment>
Next, a microbubble generator according to a fourth embodiment will be described with reference to FIG. FIG. 5 is a schematic configuration diagram showing an impeller 11 according to the fourth embodiment. Details of each part not directly related to the fourth embodiment of the present invention are omitted.

  Compared to the first embodiment, the fourth embodiment is different in that the shape of the wing body 12 is changed and the position of the air supply port 14 is changed. Since the other points are the same as those in the first embodiment, details of each part not directly related to the fourth embodiment are omitted. Also, description of the same reference numerals as those in the first embodiment is omitted.

  FIG. 5A is a front view of the impeller 11 according to the fourth embodiment. FIG. 5B is a plan view of the impeller 11 according to the fourth embodiment. FIG. 5C is a cross-sectional view in plan view along the line AA shown in FIG. FIG. 5D is a front view cross-sectional view along the line BB shown in FIG.

  In the impeller 11 according to the fourth embodiment, as shown in FIGS. 5A to 5B, the wing body 12 has a predetermined height h on the side surface of the body 11 a having a cylindrical shape. Four are radially extended from the outer peripheral surface 11c of 11a. Further, the four wing bodies 12 are arranged at equal intervals in the circumferential direction of the body 11a.

  The wing body 12 includes a hollow bent pipe 16 and a cylindrical small cylinder 17. The bent pipe 16 extends in the radial direction of the body 11a, and is bent in a shape of a shape from the outer peripheral surface 11c of the body 11a toward a direction opposite to the rotation direction of the body 11a in a predetermined position in plan view. Shape. A small tube 17 is fitted at the tip of the bent pipe 16, and the tip of the small tube 17 is cut into a surface substantially perpendicular to the rotation direction of the body 11a (a surface perpendicular to the rotation direction). Has been. An elliptical opening is formed in the cut surface at the tip of the small cylinder 17, and this opening becomes an air supply port 14 for supplying air inside the body 11 a as bubbles to the liquid. In the fourth embodiment, the outer edge of the cut surface at the tip of the small cylinder 17 is the front view outer edge 12 a (front view tip 12 a) of the wing body 12.

  Next, the shape of one wing body 12 in plan view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 5C, the sectional shape of one wing body 12 in plan view extends in the radial direction of the fuselage 11a and bends in a direction opposite to the rotation direction of the fuselage 11a at a predetermined height h. Shape. One end of the bent pipe 16 constituting the wing body 12 is inserted into the outer peripheral surface 11c of the fuselage 11a along the radial direction of the fuselage 11a (the normal direction of the outer peripheral surface 11c of the fuselage 11a), The bending angle is in the direction opposite to the rotation direction of the body 11a.

  The position of the bent portion 16a of the bent pipe 16 is a position away from the outer peripheral surface 11c of the body 11a by a predetermined bending distance d4. The predetermined bending distance d4 from the outer peripheral surface 11c is a distance h (the height h of the wing body 12) from the outer peripheral surface 11c of the body 11a to the radial tip 12d of the wing body 12 (the radial tip of the small cylinder 17). ), The predetermined bending distance d4 shown in FIG. 5C corresponds to the length of one third of the height h of the wing body 12. Yes.

  The bending angle of the bent portion 16a is a predetermined angle β (acute angle) with respect to the normal line 1251 of the insertion portion of the bent pipe 16 to the body 11a. The predetermined angle β may be any angle as long as it is an acute angle, but the predetermined angle β shown in FIG. 5C is 45 degrees with respect to the normal line 1251.

  The small cylinder 17 fitted to the tip of the bent pipe 16 is cut at a substantially vertical surface 1252 with respect to the rotation direction of the body 11a. Therefore, the radial tip 12d of the wing body 12 corresponds to the upper tip of the cut surface of the small cylinder 17, and the upper tip is pointed toward the radial direction of the fuselage 11a. On the other hand, the front-view outer edge 12a of the cut surface of the small cylinder 17 has an elliptical shape whose major axis extends in the radial direction of the body 11a.

  Further, a predetermined distance from the upper tip 12d of the cut surface of the small cylinder 17 to the outer peripheral surface 11c of the body 11a corresponds to the height h of the wing body 12. The height h of the wing body 12 is preferably set within a range of 2/3 to 1/5 of the outer diameter R of the fuselage 11a, and further, a range of 1/3 to 1/4. It is preferable to be within. The height h of the wing body 12 shown in FIG. 5C is 15 mm, the outer diameter R of the fuselage 11a is 30 mm, and the inner diameter is 25 mm. When the impeller 11 is rotated, the rotational torque of the impeller 11 applied to the upper tip 12d of the cut surface of the small cylinder 17 is maximized, and a vortex is generated from the tip and the outer edge of the cut surface.

  Since the inside of the bent pipe 16, the inside of the small cylinder 17, and the inside of the body 11 a communicate with each other, when bubbles are supplied from the air supply port 14 on the cut surface of the small cylinder 17, the bent pipe 16 and the small pipe 17 are small. Air inside the body 11 a is supplied to the air supply port 14 via the cylinder 17.

  The air supply port 14 provided in the small cylinder 17 is opened downstream of the small cylinder 17 in the rotation direction and at the position of the center 17a of the outer edge of the cut surface of the small cylinder 17 (the outer edge 12a in front view of the wing body 12). Is done. When the air supply port 14 is opened at the position, the vortex 1223 generated from the upper tip 12d of the elliptical cut surface and the outer edge 12a in front view comes into contact with the upper surface of the air supply port 14 while turning slightly. 14 is subjected to periodic water pressure fluctuations of the vortex 1223.

  The hole diameter of the air supply port 14 is preferably set within a range from 2/3 to 1/6 of the outer diameter R of the impeller 11, and further from 1/3 to 1/5. It is preferable to be within the range. The major axis of the air supply port 14 shown in FIG. 5C is 3 mm, and the height h of the wing body 12 is 15 mm.

  Next, the shape of one wing body 12 in a front view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 5D, the front view shape of one wing body 12 is a shape in which the bent pipe 16 extends in the radial direction of the fuselage 11 a, and the small cylinder 17 fixed to the bent pipe 16 has a shape. The shape of the outer edge 12a at the upper tip is formed in an elliptical shape along the radial direction from the rotating shaft 11b of the body 11a (not shown). The radius of the elliptical shape of the outer edge portion 12a corresponds to the major axis of the ellipse of the cut surface of the small cylinder 17, and the radius of the elliptical shape of the outer edge portion 12a is the ellipse of the cut surface of the small tube 17 Corresponds to the minor axis.

  The air supply port 14 is opened at the position of the center 17a (ellipse-shaped center) of the front-view outer edge 12a of the cut surface of the small cylinder 17. When the air supply port 14 is opened at the position, the vortex 1223 generated from the front view outer edge 12a (outer edge near the tip of the wing body 12) of the cut surface concentrates at the position of the center 17a of the front view outer edge 12a. The air supply port 14 is reliably subjected to periodic water pressure fluctuations of the vortex 1223.

  Thus, even if the shape of the wing body 12 and the position of the air supply port 14 described above are employed, the vortex 1223 can be easily generated. Further, since the cycle of the water pressure fluctuation of the vortex 1223 can be easily changed only by changing the rotation speed of the impeller 11, the above-described operational effects of the present invention can be obtained.

  Moreover, since the wing body 12 according to the fourth embodiment has a smaller area with respect to the front surface in the rotational direction than the wing body 12 according to the first embodiment, the water pressure received by the wing body 12 can be further reduced. It becomes possible. As a result, the power consumption of the microbubble generator 1 according to the fourth embodiment is further reduced.

<Fifth embodiment>
Next, a microbubble generator according to a fifth embodiment will be described with reference to FIG. FIG. 6 is a schematic configuration diagram showing an impeller 11 according to the fifth embodiment. Details of each part not directly related to the fifth embodiment of the present invention are omitted.

  Compared with the first embodiment, the fifth embodiment differs from the first embodiment in that the shape of the wing body 12 is changed, the number of air supply ports 14 is increased, and the position of the air supply ports 14 is changed. is there. Since the other points are the same as those in the first embodiment, details of each part not directly related to the fifth embodiment are omitted. Also, description of the same reference numerals as those in the first embodiment is omitted.

  FIG. 6A is a front view of the impeller 11 according to the fifth embodiment. FIG. 6B is a plan view of the impeller 11 according to the fifth embodiment. FIG. 6C is a cross-sectional view taken along line AA shown in FIG. FIG. 6D is a cross-sectional view taken along the line BB shown in FIG.

  In the impeller 11 according to the fifth embodiment, as shown in FIGS. 6A to 6B, a side surface of the body 11a that is a substantially rectangular parallelepiped is provided with a rectangular parallelepiped small pedestal 18, and the small pedestal 18 Four wing bodies 12 having a semicircular contact surface with water are radially extended from the outer peripheral surface 11c of the body 11a at a predetermined height. The four wing bodies 12 are respectively installed at the center of the upper surface 18a (corresponding to the outer peripheral surface of the body 11a) of the rectangular small base 18 provided on each of the substantially square sides of the body 11a.

  The wing body 12 is hollow, and the front end 12a in front view of the wing body 12 is formed in a semicircular shape along the rotation direction of the body 11a. Further, the wing body 12 is formed in a shape extending to the trunk length in a front view. Further, the wing body 12 is formed in a semicircular shape in the vicinity of the tip 12b (front edge in front view near the tip of the wing body) on the upstream side in the rotation direction of the fuselage 11a (front surface in the rotation direction), and the rotation direction of the fuselage 11a. The outer surface on the downstream side is formed in a shape perpendicular to the outer peripheral surface 18a of the body 11a.

  The air supply ports 14 for supplying air into the liquid as bubbles inside the fuselage 11a are arranged in a row with respect to the center line 12f of the wing body 12 at a predetermined interval at a position downstream of the wing body 12 in the rotation direction. There are four openings per wing 12 above.

  And the inside of the small stand 18 has a cavity for communicating the inside of the wing body 12 and the inside of the fuselage 11a.

  Next, the shape of one wing body 12 in plan view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 6C, the one wing body 12 has a semi-cylindrical shape in plan view, and the front view outer edge 12b in the vicinity of the tip of the wing body 12 is on the upstream side in the rotation direction of the wing body 12. It is formed in a semicircular shape at the upper end. Further, the wing body 12 is formed in a shape in which the surface on the downstream side in the rotation direction (rear surface in the rotation direction) is a surface substantially perpendicular to the upper surface 18a of the small base 28 to which the wing body 12 is fixed.

  Further, the tip 12d in the radial direction of the wing body 12 has a pointed shape on the downstream side in the rotation direction. When the wing body 12 rotates, the rotational torque of the impeller 11 applied to the radial tip 12d of the wing body 12 and the front-view tip 12a becomes maximum, and a vortex 1223 is generated from the tip 12d and the front-view tip 12a. Here, a predetermined distance from the radial tip 12 d of the wing body 12 to the upper surface 28 a of the small base 28 corresponds to the height h of the wing body 12.

  The height h of the wing body 12 is preferably set within a range from 4/5 to 1/5 of the length of one side of the substantially square impeller 11 including the width of the small base 18; Furthermore, it is preferable that it is in the range from 2/3 to 1/3. The height h of the wing body 12 shown in FIG. 6C is 35 mm, and the half length of one side of the impeller 11 is 38 mm.

  The inside of the wing body 12 and the inside of the fuselage 11 a are configured to communicate with each other by a small pipe 15 that penetrates the small base 18. The small pipe 15 has a cylindrical shape and is inserted from the upper surface 18a of the small base 18 toward the rotation axis of the body 11a. The end 15a of the small pipe 15 on the upper surface 18a side of the small base 18 is fitted with the lower end of the wing body 12 to fix the wing body 12 and the small base 18. Even if air is supplied from the air supply port 14 of the wing body 12 by the small pipe 15, the air inside the fuselage 11 a is supplied into the wing body 12 through the small pipe 15.

  Of the four air supply ports 14 provided in the wing body 12, the first air supply port 14 a is located downstream from the radial tip 12 d of the wing body 12 on the downstream side in the rotation direction of the wing body 12. Opening is made at a position up to a semicircular radius d5 of the outer edge 12b in plan view. When the first air supply port 14a is opened at this position, the vortex 1223 generated from the radial tip 12d of the wing body 12 makes a small turn and contacts the upper surface of the first air supply port 14a. The air mouth 14a is subjected to periodic water pressure fluctuations of the vortex 1223.

  Further, from the second air supply port 14b to the fourth air supply port 14d, the respective air supply ports 14 are viewed from above at a predetermined interval corresponding to the semicircular radius d5 of the top view outer edge 12b at the upper end. It opens so that it may arrange in a line toward the downward direction. When the plurality of air supply ports 14 are opened in a row at a predetermined interval, when the vortex 1223 generated from the radial tip 12d of the wing body 12 develops downward, the water pressure fluctuation of the developed vortex 1223 is changed to the second supply air. The mouth 14b will receive. When the vortex 1223 further develops below the wing body 12 through the upper surface of the second air supply port 14b, the third air supply port 14c receives the water pressure fluctuation.

  In this way, when the vortex 1223 generated from the radial tip 12d of the wing body 12 develops, the plurality of air supply ports 14 receive the fluctuation of the water pressure of the developed vortex 12b in a chain, and the air supply ports 14 It is possible to efficiently supply air into the liquid.

  The predetermined interval at which the air supply ports are arranged is appropriately changed in design according to the development of the vortex 1223 generated.

  The hole diameter of the air supply port 14 is appropriately changed according to the length of half of one side of the fuselage 11a, the height h of the wing body 12, and the rotational speed of the impeller 11, but It is preferably set within the range of 1/3 to 1/50 of the height h, more preferably within the range of 1/5 to 1/25, and 1/10 to 18 minutes. It is still more preferable that it is in the range up to 1. For example, the height h of the wing body 12 shown in FIG. 6C is 35 mm, and the hole diameter of the air supply port 14 is 1.5 mm.

  Next, the shape of one wing body 12 in a front view and the position where the air supply opening 14 is opened will be described.

  As shown in FIG. 6D, the front view shape of one wing body 12 has a main body formed in a trunk length, and the front view outer edge 12a in the vicinity of the tip is a semicircle with respect to the front surface in the rotation direction of the wing body 12. It is formed into a shape. The semicircular radius of the front view outer edge 12a coincides with the semicircular radius d5 of the top view outer edge 12b of the wing body 12 described above.

  The first air supply port 14 a is opened at the center of a semicircle of the front-view outer edge portion 12 a of the blade body 12 on the downstream side in the rotation direction of the blade body 12. When the first air supply opening 14a is opened at the position, the vortex 1223 generated from the outer edge 12a of the wing body when viewed from the front is concentrated at the center position of the semicircular shape. The periodic fluctuation of the water pressure of the vortex 1223 is surely received.

  Further, the second air supply port 14b to the fourth air supply port 14d are opened in a line at predetermined intervals along the upper and lower center lines 12f of the wing body 12. When the second air supply port 14b to the fourth air supply port 14d are opened at the positions, vortices 1223 generated from the left and right directions of the respective air supply ports can be concentrated on the air supply ports.

  Thus, even if the shape of the wing body 12 and the position of the air supply port 14 described above are employed, the vortex 1223 can be easily generated. Further, since the cycle of the water pressure fluctuation of the vortex 1223 can be easily changed only by changing the rotation speed of the impeller 11, the above-described operational effects of the present invention can be obtained.

  Moreover, since the wing body 12 according to the fifth embodiment has a smaller area with respect to the vertical plane in the rotation direction than the wing body 12 according to the first embodiment, the water pressure received by the wing body 12 is further reduced. It becomes possible. As a result, the power consumption of the microbubble generator 1 according to the fifth embodiment is further reduced.

  Furthermore, in the fifth embodiment, since the plurality of air supply openings 14 are configured to be opened at predetermined positions, the developed vortices can be efficiently used to generate bubbles from each of the air supply openings 14. It becomes possible to supply in the liquid.

  In the fifth embodiment, the four air inlets 14 are configured to be opened. However, the number of the air inlets 14 may be appropriately increased or decreased as long as the air inlets 14 are opened at the predetermined positions.

  In addition, the microbubble generator according to the first to fifth embodiments is employed in an aquarium for breeding edible fish, saltwater fish and freshwater fish, but other uses such as a food processing factory. Wastewater treatment tanks, wastewater treatment tanks, ginger to be installed in the sea, tanks for transport boats transported from the sea to the shore, fish tanks for fresh fish transporters, suspended solids removal tanks for the purpose of removing suspended substances and aeration in treated water, etc. May be adopted.

<Microbubble generator> (Supplemental information on configuration)
Below, the fine bubble generator 1 which concerns on this invention is demonstrated.

  FIG. 7 is a schematic diagram of the microbubble generator 1 according to the present invention. However, details of each part not directly related to the present invention are omitted. The vertical direction in FIG. 1 corresponds to the vertical direction of the fine bubble generator 1 according to the present invention, and the horizontal direction in FIG. 1 corresponds to the horizontal direction of the fine bubble generator 1 according to the present invention.

  The fine bubble generating device 1 is installed in the water W in the aquarium 101 where marine fish such as aquaculture pigs are swimming, generates fine bubbles B1 in the water W, and removes pollutants floating in the water W. Raise while adhering to the fine bubbles B1. The fine bubbles B1 rise while increasing the diameter while taking in and combining other fine bubbles B1. The large bubble B2 is not ruptured even when rising.

  The rising fine bubbles B1, the large bubbles B2, and the pollutants attached to them are transferred from a drain pipe 102 provided in the vicinity of the upper part of the water tank 101 to the filter W (not shown) separately installed along with the water W in the vicinity of the upper surface. Drained and the contaminants are removed by the filtration device. Then, the water W filtered by the filtration device is returned again into the water tank 101 from the water supply pipe 103 provided at a location different from the drain port 102.

  The fine bubble generating apparatus 1 includes a driving unit 105 in which a driving motor 104 is mounted, a rotating shaft 106 that is a driving shaft of the driving motor 104, a cylinder 107 described later, and an impeller 11. The driving unit 105 is fixed on a lid member 108 that covers the upper part of the water tank 101. The lid member 108 is provided with an opening 109 having a predetermined size, and the rotating shaft 106 of the drive motor 104, the cylinder 107, and the impeller 11 are connected to the water tank 101 through the opening 109. Inserted inside. The lid member 108 prevents dust from the outside air from entering the water tank 108.

  The rotating shaft 106 extends from the lower part of the driving unit 105 to a predetermined water level near the lower part in the water tank 101. A cylindrical body 107 having a hollow cylindrical shape having a length approximately the same as the entire length of the rotating shaft 106 in the vertical direction is provided so as to surround the rotating shaft 106. The cylindrical body 107 is configured so that the rotating shaft 106 is not immersed in the water W in the water tank 101.

  An intake port 110 is formed in the side surface near the upper end of the cylinder 107. The intake port 110 allows the outside air to communicate with the inside of the cylinder body 107, and allows the outside air to be sucked into the inside of the cylinder body 107. Thereby, the said cylinder 107 functions as a gas supply pipe | tube which supplies external air in a liquid as a bubble.

  With respect to the inside of the cylinder 107, a predetermined number of the rotation shaft 106 is inserted into the cylinder 107 at a predetermined interval in the vertical direction of the rotation shaft 106 between the rotation shaft 106 and the cylinder 107. A bearing 111 is provided. The bearing 111 allows the rotating shaft 106 to rotate smoothly inside the cylinder 107.

  Furthermore, the impeller 11 according to the present invention having a hollow cylindrical shape is fixed to the lower end portion of the rotating shaft 106.

  FIG. 8 is a front sectional view of the impeller 11 of the microbubble generator 1 according to the present invention. The vertical direction in FIG. 8 corresponds to the vertical direction of the impeller 11 according to the present invention, and the horizontal direction in FIG. 2 corresponds to the horizontal direction of the impeller 11 according to the present invention.

  As shown in FIG. 8, rotation is performed via the connecting pulp 112 corresponding to the above-described shaft tube 10 so that the inside of the cylinder body 107 into which the rotating shaft 106 is inserted and the inside of the body 11 a of the impeller 11 communicate with each other. The shaft 106 and the body 11a are fixed. That is, the connection pulp 112 has a hollow cylindrical shape, and the upper end portion of the connection pulp 112 is fitted and connected to the lower end portion of the rotating shaft 106, and the lower end portion of the connection pulp 112 is a donut-shaped lid member 113 described later. To the upper end of the body 11a.

  The donut-shaped lid member 113 is fitted to the inner peripheral surface of the trunk 11a and the outer peripheral surface of the connecting pulp 112 so as to closely bond the connecting pulp 112 and the trunk 11a. The donut-shaped lid member 113 prevents the air inside the body 11 a from leaking into the water W in the water tank 101.

  Further, a predetermined number of air inlets 13 are opened near the position where the connecting pulp 112 and the rotating shaft 106 are fitted, and the inside of the cylinder 107 and the inside of the connecting pulp 112 are communicated with each other. Yes.

  Further, a cap 114 having an opening substantially the same as the outer diameter of the connection pulp 112 is attached to the lower end portion of the cylindrical body 107 below the position of the intake port 13 provided in the connection pulp 112. The cap 114 inserts the connection pulp 112 from the opening, transmits the rotation of the rotating shaft 106 to the body 11a, and prevents water W from entering the inside of the cylinder 107.

  The lower end of the body 11a is closed by a mecha cap 115 that seals the inside of the body 11a, and the air inside the body 11a is supplied to the liquid from an air supply opening 14 that is opened on the side surface of the body 11a. I will be worried. Since the inside of the body 11a communicates with the outside through the air inlet 110 of the cylindrical body 107 and the air inlet 13 of the connection pulp 112, air enters the liquid from the air inlet 110 of the cylindrical body 107 as bubbles. When supplied, the air pressure inside the body 11a decreases, and the outside air is supplied to the inside of the body 11a through the air inlet 13 of the connection pulp 112.

  As shown in FIG. 1, a long axial tube 10 may be prepared to constitute the microbubble generator 1 according to the present invention. As shown in FIGS. You may comprise like the connection pipe 112. FIG.

  As described above, the microbubble generator according to the present invention is useful not only for aquaculture tanks for breeding seawater fish but also for wastewater treatment tanks of food processing plants, wastewater treatment tanks, etc. It is effective as a fine bubble generator capable of efficiently generating bubbles.

10 shaft pipe 11 impeller 11a fuselage 12 wing body 13 air inlet 14 air inlet

Claims (4)

With a shaft tube rotated,
The outer periphery of the body attached to the tip of the shaft tube extends from the rotation axis of the shaft tube to a predetermined distance in the radial direction of the shaft tube, and the most advanced as viewed from the rotation direction of the shaft tube. An impeller with a circular wing,
When the impeller rotates in the liquid, the contact peripheral surface between the leading edge of the wing body and water forms a semicircular shape, and vortices generated downstream from the leading edge of the wing body in the rotation direction of the wing body. 3 minutes of the height of the wing body with respect to the outer peripheral surface of the fuselage at a predetermined position of the fuselage at the downstream side in the rotation direction of the wing body and in the vicinity of the center of the semicircular shape of the wing body , subjected to water pressure fluctuation An air supply port having a hole diameter set in a range of 1 to 1/50 and communicating with outside air via a cavity provided in the body and a shaft tube;
A fine bubble generator comprising: means for adjusting a pore diameter of the fine bubbles generated in the liquid according to the number of rotations of the impeller . 2. The fine bubble generating device according to claim 1 , wherein the height of the wing body is set within a range from two thirds to one fifth of an outer diameter of the fuselage . The cross-sectional shape of the wing body viewed from the axial direction of the axial tube is a wing shape curved to the downstream side in the rotation direction of the fuselage,
The tip of the wing body is sharply formed along the direction opposite to the rotational direction of the fuselage when viewed from the axial direction of the axial tube,
The air supply opening is opened at a point of intersection of a straight line drawn from the tip of the wing body viewed from the rotation direction of the wing body toward the rotation axis of the fuselage and the outer peripheral surface of the fuselage. The fine bubble generating apparatus according to claim 1 or 2 . The wing body has an outer surface on the upstream side in the rotation direction of the fuselage as viewed from the axial center direction of the shaft tube as an inclined surface inclined at a predetermined angle with respect to a direction perpendicular to the rotation direction. The outer surface on the downstream side in the rotational direction of the body as seen from the axial direction is formed in a trapezoidal shape that is perpendicular to the rotational direction,
The tip of the wing body is formed on a surface along the rotational direction of the fuselage as viewed from the axial direction of the axial tube,
The air supply opening is opened at a position moved along the rotation direction by a predetermined opening distance within the height of the wing body from the intersection of the trapezoidal vertical surface of the wing body and the outer peripheral surface of the fuselage. The fine bubble generating device according to claim 1 or 2 .