Microbubble generator and sprinkler

Abstract

To provide a new fine bubble generation device which can generate fine bubbles simply and effectively, and to provide a watering device.SOLUTION: A fine bubble generation device has at least a load generation part and a turbulent flow generation part F. The load generation part comprises: a diameter reduction passage B; and a small diameter passage C which is continuous with the diameter reduction passage B. The turbulent flow generation part F has a turbulent flow generation structure 7 where a liquid current flowing in a passage comprising a diameter expanding passage D which is continuous with the small diameter passage C and a large diameter passage E which is continuous with the diameter expanding passage D collides. The above object is achieved by the fine bubble generation device. The turbulent flow generation structure 7 comprises: a recessed part 7a which is provided in a circular shape in a downstream direction Y along an inner peripheral surface 6 of the large diameter passage E and with which liquid 18 collides to be bounced back, a protruding part 7b which is provided in a circular shape at a center side of the large diameter passage E and partitions the recessed part 7a; and an outlet passage 7c which is provided at a center side of the protruding part 7b and causes turbulent flow liquid 19 bounced back to flow in the downstream direction Y.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a microbubble generator that generates microbubbles in a liquid and a sprinkler system equipped with the same. [Background technology]

[0002] Liquids containing tiny (also called "micro") bubbles are expected to be used in a variety of industrial fields, and in recent years, various methods for generating microbubbles have been proposed. Among the generated bubbles, those with a size of 1 to 100 μm are called microbubbles.

[0003] Patent Document 1, for example, proposes a microbubble water generator that can be easily attached to household appliances such as shower heads and washing machines by directly connecting to a tap water supply pipe. This microbubble water generator connects to the water supply end of a shower hose at the first cylindrical portion of the main case and to the water intake end of the shower head at the second cylindrical portion. A water intake plate with multiple water intake holes is fitted into the first cylindrical portion. A nozzle located downstream of the water intake plate includes a first water passage whose diameter gradually decreases in the direction of tap water flow through the water intake plate, and a second water passage that communicates with the outlet of the first water passage and gradually increases in diameter in the direction of tap water flow. The water intake holes have a central axis extending from the inlet to the outlet that is inclined relative to the central axis of the water intake plate.

[0004] Patent Document 2 proposes a bubble generating device that can generate a large amount of high-density bubbles with smaller diameters, for example, less than 1 μm, in a short period of time without requiring a high pump discharge pressure. This bubble generating device includes a metal capillary tube through which water flows and a pump that pumps water containing gaseous components into the metal capillary tube. A throttle section is provided inside the metal capillary tube, where the water passage is narrower than its front and rear ends in the direction of water flow. The throttle section has a rectangular cross section perpendicular to the direction of flow. Pumping water into the throttle section dissolves the gaseous components in the water, and a pressure drop at the throttle section causes bubbles to precipitate. Turbulence is generated in the water at the throttle section, which breaks up the bubbles in the water with the shear force. Finally, shock waves generated by transonic flow in the water exiting the throttle section break up the bubbles.

[0005] Patent Document 3 proposes a liquid treatment device that uses a liquid treatment nozzle with a structure that uses a screw member to perform cavitation treatment, enabling gas dissolution treatment to be performed significantly more efficiently than conventional methods, and that can generate sufficient cavitation even when using a liquid to be treated that is deficient in dissolved gas. This liquid treatment device includes a gas-liquid mixer with a spiral flow path upstream of the liquid treatment nozzle. By circulating a multiphase flow through the spiral flow path of the gas-liquid mixer, the centrifugal force of the forced spiral flow promotes agitation and mixing of the gas and liquid phases, and the gas phase is supplied to the screw member of the liquid treatment nozzle in a state where it is crushed into fine bubbles. This increases the contact efficiency between the gas-containing liquid and the thread root, thereby improving the gas dissolution efficiency. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2019-25451 [Patent Document 2] WO2018 / 021182 [Patent Document 3] Japanese Patent Publication No. 2020-189274 Summary of the Invention [Problem to be solved by the invention]

[0007] Liquids containing fine bubbles are expected to be applied in a variety of fields, including cleaning, beauty, agriculture, medicine, etc. An object of the present invention is to provide a new fine bubble generator that can generate fine bubbles simply and effectively, and a sprinkler system equipped with the same. [Means for solving the problem]

[0008] The micro-bubble generator according to the present invention is characterized in that it has at least a negative pressure generating section and a turbulent flow generating section, the negative pressure generating section being composed of a narrowing-diameter flow path and a small-diameter flow path continuous with the narrowing-diameter flow path, and the turbulent flow generating section having a turbulent flow generating structure with which liquid flows flowing through a flow path composed of an enlarged-diameter flow path continuous with the small-diameter flow path and a large-diameter flow path continuous with the enlarged-diameter flow path collide.

[0009] According to this invention, the load generating section is composed of a reduced-diameter flow path and a small-diameter flow path connected to the reduced-diameter flow path, which increases the flow rate and generates negative pressure in the liquid, causing bubbles to separate from dissolved air in the liquid through the cavitation effect. Furthermore, the turbulence generating section has a turbulence generating structure with which liquid flows collide through a flow path composed of an expanded-diameter flow path connected to the small-diameter flow path and a large-diameter flow path connected to the expanded-diameter flow path. This turbulence generating structure creates turbulence in the liquid and pressurizes it to break down bubbles. As a result, fine bubbles can be generated simply and effectively.

[0010] In the micro-bubble generator according to the present invention, the turbulence generating structure is composed of a circular recessed portion provided downstream along the inner circumferential surface of the large-diameter flow path, against which the liquid collides and rebounds, a circular protruding portion provided centrally of the large-diameter flow path and defining the recessed portion, and an outlet flow path provided centrally of the protruding portion and for causing the rebounded turbulent liquid to flow downstream.

[0011] According to this invention, the turbulence generating structure is composed of the recessed portion, the protruding portion, and the outlet flow path, so that the liquid flowing along the inner circumferential surface of the large-diameter flow path hits the recessed portion and rebounds, generating turbulence. The generated turbulent liquid flows downstream in the flow path provided on the center side of the protruding portion.

[0012] In the micro-bubble generator according to the present invention, the flow path provided continuously to the center of the large-diameter flow path is a second load generating section, and the second load generating section is composed of a second small-diameter flow path having the same or approximately the same diameter as the small-diameter flow path.

[0013] According to this invention, the flow path provided continuously to the center side of the large diameter flow path is the second load generating section, and this second load generating section is composed of a second small diameter flow path having the same or approximately the same diameter as the small diameter flow path, so that negative pressure can be generated in the liquid again to precipitate bubbles from the dissolved air in the liquid.

[0014] In the micro-bubble generator according to the present invention, the liquid flowing through the load generating section is pressurized liquid. According to this invention, the pressurized liquid flows through the load generating section, thereby further enhancing the cavitation effect in the load generating section.

[0015] In the micro-bubble generator according to the present invention, the circular convex portion has one or more notches formed in the height direction. According to this invention, even if a solid object that restricts the flow of liquid is present in the large-diameter flow path, the notches in the convex portion can prevent the flow path from being blocked by the solid object.

[0016] In the micro-bubble generator according to the present invention, the large-diameter flow channel may optionally contain free solid objects that restrict the flow of the liquid, or free solid objects whose components gradually decrease. According to this invention, by optionally placing free solid objects that restrict the flow of the liquid in the large-diameter flow channel, the flow of the liquid can be regulated to more closely follow the inner circumferential surface of the large-diameter flow channel. As a result, the liquid can be effectively impinged against the recesses, generating a stable turbulent flow. Furthermore, by optionally placing free solid objects whose components gradually decrease in the large-diameter flow channel, the components can be contained in the micro-bubble-containing fluid. As a result, the micro-bubble-containing fluid can be utilized depending on the components.

[0017] In the micro-bubble generating device according to the present invention, a second enlarged diameter flow path is connected to the second small diameter flow path.

[0018] In the micro-bubble generator according to the present invention, an air intake port is provided at the boundary between the small-diameter flow path and the expanded-diameter flow path, or at the end of the small-diameter flow path on the expanded-diameter flow path side. According to this invention, since the air intake port is provided at the end of the small-diameter flow path on the expanded-diameter flow path side or in the vicinity thereof (at the boundary), any gas can be introduced into the flow path through the air intake port depending on the application. As a result, functional water containing gas can be produced, and effects according to the type of gas can be achieved.

[0019] The sprinkler according to the present invention is characterized in that it includes the micro-bubble generator according to the present invention in its grip. According to this invention, the micro-bubble generator is provided in the grip of the sprinkler, so that micro-bubbles can be generated in the grip with an appearance that is no different from that of a conventional sprinkler. As a result, a sprinkler that can generate micro-bubbles simply and effectively can be provided. [Effects of the Invention]

[0020] According to the present invention, the flow velocity is increased in the load generating section, generating negative pressure in the liquid, which causes bubbles to precipitate from dissolved air in the liquid through the cavitation effect, and the liquid is made turbulent and pressurized to break down the bubbles, thereby generating fine bubbles simply and effectively.As a result, liquids containing fine bubbles are expected to be used in a variety of fields, including cleaning, beauty, agriculture, and medicine. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a perspective view showing an example of a fine bubble generating device according to the present invention. FIG. [Figure 2] 2A and 2B are a front view and a side view, respectively, of the microbubble generator shown in FIG. 1. [Figure 3] FIG. 2 is a cross-sectional view of the micro-bubble generating device shown in FIG. [Figure 4] 2 is a diagram showing the flow of liquid in the micro-bubble generator shown in FIG. 1. [Figure 5] FIG. 4 is a configuration diagram of the second member as seen from the flange portion side. [Figure 6] FIG. 10 is a cross-sectional view showing another example of the micro-bubble generating device according to the present invention. [Figure 7] FIG. 1 is a cross-sectional view showing an example of a micro-bubble generating device in which a solid object is placed in a turbulent flow-forming channel. [Figure 8] FIG. 1 is a cross-sectional view showing an example of a fine bubble generating device equipped with an air intake port. [Figure 9] 1A is an external view of the grip portion of the sprinkler device according to an embodiment of the present invention, and FIG. 1B is a partial cross-sectional view of a microbubble generator provided within the grip portion. DETAILED DESCRIPTION OF THE INVENTION

[0022] The micro-bubble generator and sprinkler system according to the present invention will be described with reference to the drawings. Note that the following embodiment is an example of the technical concept of the present invention, and the technical scope of the present invention is not limited to the following description and drawings, but includes inventions with similar technical concepts.

[0023] [Basic configuration] 1 to 5, the fine-bubble generator 1 according to the present invention has at least a load generating section and a turbulent flow generating section F, the load generating section being composed of a reduced-diameter flow path B and a small-diameter flow path C continuing from the reduced-diameter flow path B, and the turbulent flow generating section F having a turbulent flow generating structure 7 at which liquid flows collide through a flow path composed of an expanded-diameter flow path D continuing from the small-diameter flow path C and a large-diameter flow path E continuing from the expanded-diameter flow path D. A sprinkler 70 according to the present invention has the fine-bubble generator 1 described above installed in a grip section 71.

[0024] In this micro-bubble generator 1, the load generating section is composed of a narrowing-diameter channel B and a small-diameter channel C connected to the narrowing-diameter channel B. This increases the flow rate, generating negative pressure in the liquid, which causes bubbles to precipitate from the dissolved air in the liquid through the cavitation effect. Furthermore, the turbulence generating section F has a turbulence generating structure 7 where liquid flows collide through a channel composed of an expanding-diameter channel D connected to the small-diameter channel C and a large-diameter channel E connected to the expanding-diameter channel D. This makes the liquid turbulent and pressurizes it, breaking down the bubbles into smaller pieces. As a result, micro-bubbles can be generated simply and effectively. When this micro-bubble generator 1 is connected to a pipe and liquid is passed through it, micro-bubbles are generated, and the liquid containing the micro-bubbles can be supplied downstream.

[0025] In the present invention, "bubbles" refer to spherical objects contained in a liquid, and are synonymous with "fine bubbles" as used herein. These bubbles are microbubbles with a diameter of 1 to 100 μm, and the fine bubble generator 1 can be preferably used as a generator for generating microbubbles with a diameter of 1 to 100 μm.

[0026] Each component will be described in detail.

[0027] <Micro-bubble generator> The micro-bubble generator 1 is not particularly limited as long as it has at least a load generating section and a turbulent flow generating section F, but examples of the configuration include those shown in Figs. 1 to 5. The illustrated micro-bubble generator 1 has the turbulent flow generating section F in a large-diameter flow path E located in the center of the flow path. Therefore, for ease of manufacture, it is preferable that the two members (first member 10 and second member 20) are separably connected at the large-diameter flow path E. This connection is preferably achieved by fixing a flange 13 provided on the outer periphery of the downstream opening 17 of the first member 10 and a flange 23 provided on the outer periphery of the upstream opening 27 of the second member 20 via their respective connecting holes 16, 26. In the illustrated example, the first member 10 and the second member 20 are divided into two in the flow direction Y and connected by a large-diameter flow path E in the center of the flow direction Y, but this is not limited to this. The first member 10 and the second member 20 may be divided vertically so that the cross section is parallel to the flow direction Y, and the two vertically divided members may be connected (not illustrated).

[0028] Below, we will explain the specific structural form of a micro-bubble generator 1 in which two members (a first member 10 and a second member 20) are separably connected by a large-diameter flow path E, and the flow paths A to H realized by that structural form, based on Figures 1 to 5.

[0029] (First member) As shown in FIGS. 1 to 3, the first member 10 has an opening 11 on the upstream side through which the liquid flows in, and an opening 17 on the downstream side through which the liquid flows out to the second member 20. A flow path is formed in the main body 12. As shown in FIG. 3, the flow path is arranged in the following order from the upstream side: an inlet flow path A, a reduced-diameter flow path B, a small-diameter flow path (first small-diameter flow path) C, and an expanded-diameter flow path (first expanded-diameter flow path) D. Note that, although the present invention has at least a load generating section and a turbulent flow generating section F, the negative pressure generating section can preferably be configured by the reduced-diameter flow path B and the small-diameter flow path C.

[0030] A connecting portion (e.g., a threaded portion) 15 for connecting to a piping member (not shown) is provided on the upstream side of the first member 10. A flange portion 13 for connecting to a second member 20 is provided on the downstream side of the first member 10. This flange portion 13 is provided on the outer periphery of an opening 17 on the downstream side, and can be fixed to a flange portion 23 provided on the outer periphery of an opening 27 on the upstream side of the second member 20 by respective connecting holes 16, 26. The shape of the connecting portion 15 is designed according to the type of piping member. When the piping member is a threaded type, it is preferable that the connecting portion 15 also has a threaded type corresponding to the piping member, as shown in FIG. 1 etc. On the other hand, when the piping member is a hose or a polyvinyl chloride pipe, it is preferable that the connecting portion 15 also has a connecting structure corresponding to the piping member. The main body 12 of the first member 10 has a notch 14. This notch 14 is not an essential component, but is provided so that the first member 10 can be fixed and screwed together with a tool such as a wrench when, for example, screwing together with the above-mentioned piping member (not shown).

[0031] (Second member) As shown in FIGS. 1 to 3, the second member 20 has an opening 27 on the upstream side through which the liquid flowing out from the first member 10 flows in, and an opening 21 on the downstream side through which the liquid flows out. A flow path is formed in the main body 22. As shown in FIG. 3, the flow path is arranged in the following order from the upstream side: a turbulent flow-generating flow path (large-diameter flow path) E, a turbulent flow generating section F, a small-diameter flow path (second small-diameter flow path) G, and an expanded-diameter flow path (second expanded-diameter flow path) H. While the present invention includes at least a load generating section and a turbulent flow generating section F, turbulent liquid 19 can be generated by a turbulent flow generating structure 7 where liquid flows collide through a flow path composed of an expanded-diameter flow path (first expanded-diameter flow path) D and a large-diameter flow path E. The load generating section connected to the turbulent flow generating section F is preferably composed of a second small-diameter flow path G and a second expanded-diameter flow path H, but its installation is optional and can be provided as needed.

[0032] A flange portion 23 for connecting to the first member 10 is provided on the upstream side of the second member 20. This flange portion 23 is provided on the outer peripheral edge of the upstream opening 27, and can be fixed to the flange portion 13 provided on the outer peripheral edge of the downstream opening 17 of the first member 10 by the respective connecting holes 16, 26. Figure 5 is a structural diagram of the second member 20 seen from the flange portion 23 side, showing an example in which four connecting holes 26 are provided at equal intervals. Reference numeral 31 denotes a seal member mounting portion for mounting a seal member, and the seal member is placed in the seal member mounting portion 31 when connecting the two flange portions 13, 23.

[0033] A connecting portion (e.g., a threaded portion) 25 for connecting to a piping member (not shown) is provided on the downstream side of the second member 20. The shape of this connecting portion 25 is designed depending on the type of piping member. When the piping member is threaded, as shown in FIG. 1, etc., it is preferable that the connecting portion 25 also has a threaded form corresponding to the piping member. On the other hand, when the piping member is a hose or a polyvinyl chloride pipe, it is preferable that the connecting portion 25 also has a connection structure corresponding to the piping member. A notch 24 is provided in the main body 22 of the second member 20. Although this notch 24 is not an essential component, it is provided so that the second member 20 can be fastened to the above-mentioned piping member (not shown) while being fixed with a tool such as a wrench.

[0034] (Flow path and liquid flow) 3 is configured in the following order from upstream to downstream in the direction Y: inlet channel A, reduced-diameter channel B, small-diameter channel (first small-diameter channel) C, expanded-diameter channel (first expanded-diameter channel) D, large-diameter channel E, small-diameter channel (second small-diameter channel) G, and expanded-diameter channel (second expanded-diameter channel) H. The turbulent flow generating section F has a turbulent flow generating structure 7 where liquid flows collide through a channel configured of the expanded-diameter channel D continuous with the small-diameter channel C and the large-diameter channel E continuous with the expanded-diameter channel D.

[0035] The inlet flow path A is the first flow path when liquid flows into this micro-bubble generator 1. The inner diameter of the inner circumferential surface 2 is the same over the entire length of the flow path A. The inner diameter size is not particularly limited, but can be, for example, about 5 to 15 mm. The example shown is about 11 mm. Note that the inner diameters of the following flow paths are merely examples and are not limited to the respective descriptions.

[0036] The reduced diameter flow path B is a flow path located continuously between the inlet flow path A and the first small diameter flow path C. The inner diameter of its inner circumferential surface 3 continuously decreases toward the first small diameter flow path C in the downstream direction. The size of the inner diameter is not particularly limited, but it can be reduced to about one-third (e.g., about 4 mm) of the inner diameter on the inlet flow path A side (e.g., about 11 mm).

[0037] The first small-diameter flow path C is a flow path located continuously between the reduced-diameter flow path B and the first expanded-diameter flow path D. The inner diameter of its inner circumferential surface 4 is the same as the diameter of the downstream side of the reduced-diameter flow path B over the entire length of the flow path C. The size of the inner diameter is not particularly limited, but can be, for example, about 4 mm as described above.

[0038] The first expanded diameter flow path D is a flow path located continuously between the first small diameter flow path C and the large diameter flow path E. The inner diameter of its inner circumferential surface 5 continuously increases toward the large diameter flow path E in the downstream direction. The size of the inner diameter is not particularly limited, but it can be expanded to about three times (e.g., about 11 mm) the inner diameter on the side of the first small diameter flow path C (e.g., about 4 mm), and can be the same inner diameter as the inlet flow path A, for example.

[0039] The large-diameter flow path E is a flow path located continuously between the first expanded-diameter flow path D and the second small-diameter flow path G. The inner diameter of its inner circumferential surface 6 is the same as the diameter of the downstream side of the first expanded-diameter flow path D over the entire length of the flow path E. The size of the inner diameter is not particularly limited, but can be, for example, about 11 mm as described above.

[0040] The second small-diameter flow path G is a flow path located continuously between the large-diameter flow path E and the second expanded-diameter flow path H. The role of this second small-diameter flow path G is the same as that of the first small-diameter flow path C described above. The inner diameter of its inner circumferential surface 8 is the same as that of the outlet flow path 7c provided downstream of the large-diameter flow path E over the entire length of the flow path G. The size of the inner diameter is not particularly limited, but can be, for example, about 4 mm, the same as that of the first small-diameter flow path C.

[0041] The second enlarged-diameter flow path H is a flow path located continuously with the second small-diameter flow path G. The inner diameter of its inner circumferential surface 9 increases continuously in the downstream direction. The size of the inner diameter is not particularly limited, but it can be set to an inner diameter that is approximately 3 to 4 times (e.g., approximately 11 to 17 mm) larger than the inner diameter of the second small-diameter flow path G (e.g., approximately 4 mm).

[0042] FIG. 4 shows the liquid flows f1 to f9 of the liquid 18 in each of these flow paths. As shown in FIG. 4, the liquid flow f1 in the inlet flow path A becomes a liquid flow f2 moving toward the center in the reduced-diameter flow path B, and then becomes a liquid flow f3 moving straight downstream in the first small-diameter flow path C. Then, in the first expanded-diameter flow path D, it becomes a liquid flow f5 moving straight and a liquid flow f4 moving along the expanded inner circumferential surface 5. The liquid flow f4 moving along the expanded inner circumferential surface 5 moves along the inner circumferential surface 6 of the large-diameter flow path E, and when it hits the recessed portion 7a constituting the turbulence generating structure 7, it becomes a turbulent flow 19, becoming a liquid flow f7 flowing out of the outlet flow path 7c. Then, the liquid flow f8 flowing through the second small-diameter flow path G becomes a liquid flow f9 in the second expanded-diameter flow path H and flows out of the opening 21.

[0043] <Air bubble deposition> The load generating section is composed of a diameter-reducing flow path B and a small-diameter flow path C that is continuous with the diameter-reducing flow path B. Because the load generating section is composed of a diameter-reducing flow path B and a small-diameter flow path C that is continuous with the diameter-reducing flow path B, the flow rate increases, generating negative pressure in the liquid, and the cavitation effect causes bubbles to precipitate from the dissolved air in the liquid.

[0044] The liquid flowing into the load-generating section is preferably pressurized. Since bubbles are unlikely to form at pressures below 0.15 MPa and readily form at pressures above 0.15 MPa, the pressure is preferably 0.15 MPa or higher. While there is no particular upper limit, a higher pressure is preferable because the number of bubbles increases as the pressure increases. The upper limit can be set at 5.0 MPa, due to the simple structure that can withstand pressure and durability and accommodate the allowable pressure of a power sprayer that can be easily connected and used. When liquid with a pressure between 0.15 and 5 MPa flows into the load-generating section, the flow rate increases, further enhancing the cavitation effect and facilitating the precipitation of bubbles from dissolved air.

[0045] <Occurrence of turbulence> The turbulent flow generating section F has a turbulence generating structure 7 where liquid flows collide through a channel consisting of an expanded-diameter channel D connected to a small-diameter channel C and a large-diameter channel E connected to the expanded-diameter channel D. Because the turbulent flow generating section F is composed of an expanded-diameter channel D connected to a small-diameter channel C and a large-diameter channel E connected to the expanded-diameter channel D, as shown in Figure 4, the first expanded-diameter channel D becomes a liquid flow f5 that proceeds straight and a liquid flow f4 that proceeds along the expanded inner circumferential surface 5. The liquid flow f4 that proceeds along the expanded inner circumferential surface 5 proceeds along the inner circumferential surface 6 of the large-diameter channel E and hits the recessed portion 7a that constitutes the turbulence generating structure 7, becoming a turbulent liquid 19. Furthermore, the turbulent liquid 19 is pressurized as it passes through the small-diameter outlet channel 7c, which breaks down the bubbles generated in the load generating section. As a result, fine bubbles can be generated simply and effectively.

[0046] 4 and 5, the turbulence generating structure 7 constituting the turbulent flow generating section F is composed of a circular recess 7a arranged in the downstream direction Y along the inner circumferential surface 6 of the large-diameter flow path E, against which the liquid 18 collides and rebounds; a circular protrusion 7b arranged in the center of the large-diameter flow path E to define the recess 7a; and an outlet flow path 7c arranged in the center of the protrusion 7b to allow the rebounded turbulent liquid 19 to flow in the downstream direction Y. In this micro-bubble generator 1, the turbulence generating structure 7 is composed of the recess 7a, the protrusion 7b, and the outlet flow path 7c. As described above, the liquid flowing along the inner circumferential surface 6 of the large-diameter flow path E collides with the recess 7a and rebounds, generating a turbulent liquid flow f6. The generated turbulent liquid 19 flows in the downstream direction Y through the outlet flow path 7c arranged in the center of the protrusion 7b.

[0047] As shown in Fig. 5, the circular convex portion 7b preferably has one or more notches in the height direction. In the example of Fig. 5, two notches are provided. In this micro-bubble generator 1, even if a solid object (e.g., a loose solid object 41, described later) that restricts the flow of liquid is present in the large-diameter flow path E, the notches 7d in the convex portion 7b can prevent the flow path from being blocked by the solid object. Fig. 6 shows another example of the micro-bubble generator 1 according to the present invention in which such notches 7d are not provided. The notches 7d are not an essential component and can be provided as needed, and the depth of the notches can also be selected as desired.

[0048] <Second bubble precipitation> The flow path connected to the outlet flow path 7c on the center side of the large-diameter flow path E is a second load generating section. The second load generating section is composed of a second small-diameter flow path G having the same or approximately the same diameter as the small-diameter flow path C. In this micro-bubble generator 1, the flow path connected to the center side of the large-diameter flow path E is a second load generating section connected to the turbulent flow generating section F, and this second load generating section is composed of a second small-diameter flow path G having the same or approximately the same diameter as the first small-diameter flow path C. Therefore, negative pressure can be generated again in the liquid, causing bubbles to precipitate from the dissolved air in the liquid. Note that the negative pressure generating section described above will be referred to as the first negative pressure generating section, and will sometimes be described separately from this second negative pressure generating section.

[0049] It is preferable that the liquid flowing through this second negative pressure generating section is subjected to a pressure approximately the same as that described above for the first negative pressure generating section, but a detailed description thereof will be omitted here.

[0050] <Free solids> If necessary, free solid objects 41 that restrict the flow of liquid may be placed in the large-diameter flow path E, or free solid objects 41 whose components gradually decrease may be placed. In this micro-bubble generator 1, by optionally placing free solid objects 41 that restrict the flow of liquid in the large-diameter flow path E, the flow of liquid can be restricted to follow the inner circumferential surface 6 of the large-diameter flow path E more closely. As a result, the liquid can be effectively collided against the recesses 7a, generating a stable liquid flow f6 (turbulent flow).

[0051] Furthermore, by optionally placing free solids 41, the components of which gradually decrease, into the large-diameter flow path E, the components can be contained in the micro-bubble-containing fluid. As a result, the micro-bubble-containing fluid can be utilized depending on the components. Such components can be selected depending on the application of the micro-bubble generator 1. For example, when used in the cleaning field, free solids containing detergent components can be selected; when used in the beauty field, free solids containing cosmetic components can be selected; when used in the agriculture field, free solids containing nutritional components, pesticide components, pest control components, etc. can be selected; and when used in the medical field, free solids containing medicinal components can be selected.

[0052] The size and shape of the free solid matter 41 are not particularly limited, but it is preferable that the size and shape are such that they can moderately regulate the flow without excessively obstructing the liquid flow when they enter the large-diameter flow path E. The shape is also not particularly limited, and can be selected from spheres, cubes, irregular shapes, etc., as long as it does not impair the effects of the present invention.

[0053] The free solids 41 are not fixed in the large-diameter flow path E and exist in a free state, so they move freely. Therefore, depending on the fluid pressure, it is possible to make the vibration frequency of the liquid and the vibration frequency of the free solids 41 equal, causing resonance. When resonance occurs, more bubbles than usual can be precipitated.

[0054] <Vaporization of bubbles> As described above, the micro-bubble generator 1 according to the present invention is characterized by its ability to precipitate bubbles from dissolved air in a liquid by the cavitation effect. However, after the micro-bubble-containing fluid is discharged from the nozzle, the precipitated bubbles vaporize. In this way, dissolved oxygen already present in the liquid precipitates and then vaporizes, thereby degassing the liquid. Degassed water has the advantage of improving permeability and providing antioxidant properties, so liquids can be degassed and used depending on the application and purpose.

[0055] <Air intake> FIG. 8 is a cross-sectional view showing an example of a fine-bubble generator 1 equipped with an air intake port 61. In the fine-bubble generator 1, the air intake port 61 may be provided at the boundary between the small-diameter flow path C and the expanded-diameter flow path D, or may be provided at the end of the small-diameter flow path C on the expanded-diameter side as shown in FIG. 8. Since the air intake port 61 is provided at the end of the small-diameter flow path C on the expanded-diameter flow path D side or in the vicinity thereof (boundary), any gas can be introduced into the flow path through the air intake port 61 depending on the application. As a result, functional water containing gas can be produced, and effects according to the type of gas can be achieved.

[0056] The diameter and length of the intake port 61 are not particularly limited. An intake pipe (not shown) is connected to the intake port 61 by fitting, welding, screwing, or the like, and a gas supply pipe or gas supply tube is connected to the intake pipe to supply gas. The type of gas is selected depending on the purpose and application, and examples thereof include air, hydrogen, oxygen, nitrogen, and carbon dioxide, but other gases may also be used. For example, various applications, such as enhancing cleaning effects, can be expected by adding any gas to the microbubble-containing fluid. For example, adding hydrogen can exert antioxidant effects, adding oxygen can promote crop growth in the agricultural field, and adding nitrogen can maintain the freshness of fresh food.

[0057] 1 to 7, the first member 10 and the second member 20 are connected by flanges 13, 23, but in the micro-bubble generator 1 shown in FIG. 8, no flanges are provided, and the members are connected by a first connecting portion (female thread portion) 51 and a second connecting portion (male thread portion) 52. This type of connection has the advantage that the size (particularly the outer diameter) of the micro-bubble generator 1 can be reduced, and can be similarly applied to the micro-bubble generators 1 shown in FIGS. 1 to 7. The reference numeral 53 denotes an optional sealing portion (for example, a packing).

[0058] <Sprinkler system> FIG. 9 shows an example of a sprinkler device 70 according to the present invention. The sprinkler device 70 according to the present invention is provided with a fine-bubble generator 1 according to the present invention in a grip portion 71. FIG. 9(A) is an external view of the grip portion 71 of the sprinkler device 70, and FIG. 9(B) is a partial cross-sectional view of the fine-bubble generator 1 provided in the grip portion 71. By providing the fine-bubble generator 1 in the grip portion 71 of the sprinkler device 70, fine bubbles can be generated within a grip portion that has an appearance that is no different from a normal shape. As a result, a sprinkler device 70 that is simple and capable of generating fine bubbles effectively can be provided.

[0059] In FIG. 9, reference numeral 72 denotes a water intake section that takes in water, and a hose (not shown) is inserted into the water intake section 72. Reference numeral 73 denotes a pipe section that sends water that has passed through the grip section 71 to a tip nozzle (not shown), and a water spray nozzle (not shown) is connected to the tip of the pipe section 73. Reference numeral 74 denotes a water volume adjustment lever. By moving this water volume adjustment lever 74 back and forth with a finger, the internal flow path is expanded or narrowed, thereby adjusting the water volume. Note that the structural configurations of the grip section 71, water intake section 72, pipe 73, and water volume adjustment lever 74 are not limited to the example in FIG. 9, and various structural configurations are possible. Furthermore, the size and length of the micro-bubble generator 1 provided in the grip section 71 are not particularly limited, and can be designed as desired depending on the size and length of the grip section 71.

[0060] The micro-bubble generator 1 described above increases the flow rate in the load generating section, generating negative pressure in the liquid, which causes bubbles to precipitate from dissolved air in the liquid through the cavitation effect. Furthermore, the liquid is turbulent and pressurized to break down the bubbles, thereby enabling simple and effective generation of micro-bubbles. As a result, liquids containing micro-bubbles are expected to be applied in a variety of fields, including cleaning, beauty, agriculture, and medicine. For example, the micro-bubble generator 1 is expected to be favorably applied in fields related to cleaning, beauty, agriculture, and medicine. It is also expected to be used in industrial fields such as food and beverage, pharmaceuticals, cosmetics, electronics (e.g., solar cells, secondary batteries, and semiconductor devices), and functional materials. [Explanation of symbols]

[0061] 1. Microbubble generator 2 Inner surface of flow path A 3 Inner surface of flow path B 4 Inner surface of C flow path 5 Inner surface of D flow path 6 Inner surface of E flow path 7 Turbulence generation structure 7a Recess 7b Convex part 7c Outlet channel 7d notch 8 G flow channel inner surface 9 Inner surface of H flow path 10 First member 11 Opening 12 Main body 13 Flange 14 Notch 15 Connecting part 16 Connection hole 17 Opening 18 liquid 19 Turbulent Liquids 20 Second member 21 Opening 22 Main body 23 Flange 24 Notch 25 Connecting part 26 Connection hole 27 Opening 31 Sealing member installation section 41 Free solids 51 First connecting part (female thread part) 52 2nd connection part (male thread part) 53 Sealing material 61 Air intake 70 Sprinkler System 71 Grip 72 Water Intake Section 73 Pipe section 74 Water volume adjustment lever A Inlet flow path B Reduced diameter channel C Small diameter flow path (first small diameter flow path) D Expanded diameter flow path (first expanded diameter flow path) E Large diameter flow channel (turbulent flow channel) F Turbulence generator G Small diameter flow path (second small diameter flow path) H Expanded diameter flow path (second expanded diameter flow path) f1~f9 Liquid flow in channels A~F Y Downstream direction (flow direction)

Claims

1. The pump has at least a load generating section and a turbulent flow generating section, the load generating section being composed of a reduced-diameter flow path and a small-diameter flow path continuous with the reduced-diameter flow path, and the turbulent flow generating section having a turbulent flow generating structure in which liquid flows flowing through a flow path composed of an expanded-diameter flow path continuous with the small-diameter flow path and a large-diameter flow path continuous with the expanded-diameter flow path collide with each other to generate turbulent liquid, the inner diameter of the inner circumferential surface of the expanded diameter flow path continuously increases toward the large diameter flow path in the downstream direction, the inner diameter of the inner circumferential surface of the large diameter flow path is the same as the diameter of the downstream side of the expanded diameter flow path over the entire length of the large diameter flow path, and the liquid flow proceeds along the inner circumferential surface of the expanded diameter flow path and also along the inner circumferential surface of the large diameter flow path continuous with the expanded diameter flow path, the turbulence generating structure comprises: a recessed portion that is circularly arranged in the downstream direction of the liquid flow that proceeds along the inner peripheral surface of the large-diameter flow path, and against which the liquid flow collides and rebounds, thereby generating the turbulent liquid; a convex portion that is circularly arranged on the central side of the large-diameter flow path and defines the recessed portion; and an outlet flow path that is centrally arranged on the convex portion and through which the rebounded turbulent liquid flows in the downstream direction.

2. 2. The micro-bubble generator according to claim 1, wherein a flow path provided continuously to the center side of the large-diameter flow path is a second load generating section, and the second load generating section is composed of a second small-diameter flow path having the same or approximately the same diameter as the small-diameter flow path.

3. 3. The micro-bubble generating device according to claim 1, wherein the liquid flowing through the load generating section is pressurized liquid.

4. 3. The micro-bubble generating device according to claim 1, wherein the circular convex portion has one or more notches formed in a height direction.

5. 3. The micro-bubble generator according to claim 1, wherein the large-diameter flow path is provided with free solid objects that restrict the flow of liquid, or free solid objects in which the components gradually decrease.

6. 3. The micro-bubble generating device according to claim 2, wherein a second enlarged diameter flow path is connected to the second small diameter flow path.

7. 3. The micro-bubble generating device according to claim 1, wherein an air intake port is provided at a boundary between the small-diameter flow path and the expanded-diameter flow path, or at an end of the small-diameter flow path on the expanded-diameter flow path side.

8. A sprinkler device comprising the microbubble generator according to claim 1 or 2 in a grip portion.

Images