Fine bubble forming device and water supply pipe unit

Abstract

A fine bubble forming device according to the present invention comprises: a substantially cylindrical housing in which an inflow flow path and an outflow flow path are continuously formed; a swirl flow formation plate that has a plurality of inclined holes and that is attached to an inflow port of the inflow flow path; and an obstacle member that is disposed in the inflow flow path and that intentionally disturbs the water flow that has passed through the swirl flow formation plate. The outflow flow path includes a throttle flow path having a small inner diameter in an intermediate region between the inflow port and an outflow port.

Description

Microbubble generating device and water pipe unit

[0001] The present invention relates to a device for forming fine bubbles in a water flow that flows through a water pipe that supplies, for example, cold or hot water.

[0002] In recent years, a technique for generating so-called "fine bubbles" (microbubbles) in water has been attracting attention as a technique that can improve the water purification and cleaning effects of water. Such "fine bubbles" are known to be classified into two types: "microbubbles" (ultrafine bubbles) with a diameter of 1 μm or more but less than 100 μm, and "ultrafine bubbles" (ultrafine bubbles) with a diameter of less than 1 μm.

[0003] Among such "fine bubbles," known techniques for generating "ultrafine bubbles" with small diameters in water include the "high-speed swirling flow method" and "pressure dissolution method," which generate "ultrafine bubbles" from "ultrafine bubbles" in water, and the "surfactant-added micropore method" and "cavitation method," which generate "ultrafine bubbles" directly in a water flow.

[0004] As an example of an application of the technology for generating the above-mentioned "fine bubbles," for example, Patent Document 1 discloses a microbubble generator for a faucet, which is an insert that has a flow path inside through which liquid discharged from a faucet passes and generates microbubbles from gas dissolved in the liquid, and has an external thread portion on its outer periphery that screws into a thread portion inside the spout of the faucet, and a space is provided upstream of the insert, and a tornado plate with an eccentric hole that swirls the liquid and increases the flow rate is placed in that space.

[0005] JP 2018-008193 A

[0006] In addition to the above-mentioned application examples, in recent years, bubble water containing a large amount of fine bubbles has begun to be used in the fields of agriculture and fisheries, as well as in the beauty industry, such as in shower heads for ordinary households, taking advantage of its high cleaning ability. In this context, there is a demand for smaller diameter fine bubbles and an increase in their generation, with the aim of further improving performance.

[0007] The present invention has been made based on the above background, and has an object to provide a fine bubble generating device that can increase the amount of fine bubbles generated.

[0008] In order to solve the above problems, one representative aspect of the present invention is a fine-bubble generating device comprising: a substantially cylindrical housing having an inlet flow path and an outlet flow path formed continuously therein; a swirl flow-forming plate having a plurality of inclined holes and attached to the inlet of the inlet flow path; and an obstruction member disposed in the inlet flow path to intentionally disturb the water flow that has passed through the swirl flow-forming plate, wherein the outlet flow path is configured to include a throttle flow path with a small inner diameter in an intermediate region between the inlet and outlet.

[0009] Another representative aspect of the present invention is a water pipe unit comprising an inlet-side connecting member to which a water flow is supplied, a micro-bubble-forming device that generates micro-bubbles in the water flow, and an outlet-side connecting member that discharges the water flow in which micro-bubbles have been formed, wherein the micro-bubble-forming device comprises a substantially cylindrical housing having an inlet flow path and an outlet flow path formed therein, a swirl-flow-forming plate having a plurality of inclined holes and attached to the inlet of the inlet flow path, and an obstruction member that is disposed within the inlet flow path and intentionally disturbs the water flow that has passed through the swirl-flow-forming plate, and the outlet flow path is configured so that a throttle flow path with a small inner diameter is formed in the intermediate region between the inlet and outlet.

[0010] According to the present invention having these configurations, the water flow that has passed through the swirl flow forming plate is further intentionally disturbed by the obstruction member, and then the water flow undergoes cavitation treatment in the outflow flow path after that, thereby further increasing the amount of fine bubbles generated.

[0011] FIG. 1 is a cross-sectional view showing an overview of a fine-bubble generating device according to Example 1, which is a representative example of the present invention. FIG. 2 is a cross-sectional view showing an overview of a flow path in the housing shown in FIG. 1. FIG. 3 is a schematic view showing an overview of a swirl flow forming plate shown in FIG. 1. FIG. 4 is a schematic view showing an overview of an obstacle member shown in FIG. 1. FIG. 4 is a cross-sectional view showing an overview of a fine-bubble generating operation using the fine-bubble generating device according to Example 1. FIG. 5 is a schematic view showing an overview of a swirl flow forming plate according to a modified example of the embodiment. FIG. 6 is a side view showing an overview of a water flow formed by a swirl flow forming plate according to a modified example of the embodiment. FIG. 7 is an external view showing an overview of a water passage pipe unit according to Example 2, which is another representative example of the present invention. FIG. 8 is a partial cross-sectional view showing an overview of a water passage pipe unit according to Example 2, which is another representative example of the present invention. FIG. 9 is an external view showing an overview of a water passage pipe unit according to a modified example of Example 2. FIG. 10 is a partial cross-sectional view showing an overview of a water passage pipe unit according to a modified example of Example 2.

[0012] Representative examples of the microbubble generating device according to the present invention will be described below with reference to FIGS. 1 to 8B.

[0013] <Example 1> Fig. 1 is a cross-sectional view showing an outline of a fine-bubble generating device according to Example 1, which is a typical example of the present invention. Fig. 2 is a cross-sectional view showing an outline of a flow path in the housing shown in Fig. 1. Fig. 3 is a schematic view showing an outline of the swirl flow forming plate shown in Fig. 1. Fig. 4 is a schematic view showing an outline of the obstacle member shown in Fig. 1.

[0014] As shown in FIG. 1 , the fine bubble generating device 100 according to the first embodiment includes, as an example, a substantially cylindrical housing 110 having an inlet flow path 112 and an outlet flow path 114 formed continuously therein, a swirl flow forming plate 120 having a plurality of inclined holes and attached to the inlet of the inlet flow path 112, and an obstruction member 130 disposed inside the inlet flow path 112 to intentionally disturb the water flow that has passed through the swirl flow forming plate 120.

[0015] As shown in Figure 2, the housing 110 is formed in a generally cylindrical shape from a material such as metal or hard plastic, and has an inlet flow channel 112 to which a swirl flow forming plate 120 is attached at one end where the water flow flows in. On the other hand, at the other end where the water flow is ejected, an inlet OP is formed continuously with the inlet flow channel 112. ｉｎand outlet OP ｏｕｔ The outlet flow path 114 is formed with an inlet OP ｉｎ and outlet OP ｏｕｔ A throttle flow path RP is formed in the intermediate region between the two.

[0016] The inflow flow passage 112 has a ring-shaped receiving portion 112a on the inflow side of the water flow to which the swirl flow forming plate 120 is attached, and an inlet OP of the outflow flow passage 114 on the outflow side of the water flow. ｉｎ At this time, the inner diameter D of the inlet flow path 112 is equal to the inlet OP of the outlet flow path 114. ｉｎ The opening diameter D2 is set so that D≧D2.

[0017] The outflow passage 114 is, for example, an inflow port OP ｉｎ A narrowing flow path RC whose inner diameter gradually decreases from the side toward the narrowing flow path RP, and a flow path from the narrowing flow path RP to the outlet OP ｏｕｔ 2, in the outflow passage 114, the inner diameter D2 of the throttle passage RP is the smallest, and the inner diameter D3 of the inflow passage OP is the smallest. ｉｎ Inner diameter D1 and outlet OP ｏｕｔ It is preferable that the relationship "D2<D3<D1" be established between the inner diameter D3 at the end of the groove and the inner diameter D2 at the end of the groove.

[0018] 3, the swirl flow forming plate 120 is, for example, composed of a substantially disk-shaped main body 122 with a plurality of inclined holes 124 formed on a substantially circular circumference, and a stepped portion 126 formed on the outer periphery of the main body 122. As shown in FIGS. 1 and 2, the stepped portion 126 of the swirl flow forming plate 120 is formed to fit into a receiving portion 112a formed in the inflow flow path 112 of the housing 110, so that the swirl flow forming plate 120 is attached without any gaps to the inflow side of the inflow flow path 112 of the housing 110. The swirl flow forming plate 120 is formed, for example, from a material such as metal or hard plastic, similar to the housing 110.

[0019] In the example shown in Figure 3, four inclined holes 124 are formed at equal intervals in the main body 122 of the swirl flow forming plate 120 between the upper surface 122a and the lower surface 122b, with the opening positions of the holes offset in the direction of arrow A1. As a result, when water flows into the bottom side of the swirl flow forming plate 120, the water flow that passes through the multiple inclined holes 124 formed in the main body 122 is ejected in the inclined direction of these inclined holes 124, resulting in a swirling flow that flows downstream. Note that Figure 3 illustrates an example in which four inclined holes 124 are formed at equal intervals on a substantially circular circumference, but the number of inclined holes 124 may be selected appropriately depending on the overall size and the properties of the flowing water flow WF.

[0020] 4, the obstruction member 130 is, for example, composed of a base member 132 shaped to be in contact with the inner surface of the inlet flow path 112 of the housing 110, and a plurality of fin members 134 arranged on the base member 132. Such obstruction member 130 intentionally disrupts the swirling flow guided from the swirling flow forming plate 120 on the downstream side, thereby further increasing the efficiency of generating fine bubbles in the downstream outlet flow path 114. Note that, like the other members, the obstruction member 130 is made of a material such as metal or hard plastic.

[0021] As an example, the height and width of the base member 132 are determined by taking into consideration a balance between maximizing the amount of water flowing through the inflow channel 112 and maximizing the number of fin members 134 that intentionally disrupt the water flow. The length of the base member 132 in the direction of the water flow is selected appropriately by conducting experiments in advance to generate microbubbles. The base member 132 may be configured to have a non-slip function based on a so-called "key and key groove" relationship between it and the inner surface of the inflow channel 112 of the housing 110.

[0022] As an example, the multiple fin members 134 have a shape that tapers from the base member 132 to the tip. The height of the fin members 134 is also set within an appropriate range so as to maximize the amount of water in the water flow WF flowing through the inflow passage 112 while also disrupting the flow of the water flow in a more complex manner.

[0023] While the fin members 134 shown in Figure 4 are arranged in three rows along the direction of the water flow, any number of rows can be used in consideration of the efficiency of disrupting the flow. Also, while Figure 4 shows the fin members 134 arranged in rows along the water flow, they may be arranged randomly as long as the purpose of the fin members 134 is to intentionally disrupt the water flow.

[0024] The micro-bubble-generating device 100 according to the present invention employs a so-called "cavitation method" as a technology for generating micro-bubbles, in which gas dissolved in liquid is generated as "ultra-fine bubbles" by the "cavitation phenomenon." This "cavitation method" does not require any additional flow paths or pipes for taking in gas such as air, which is the raw material for micro-bubbles, between the time the water flow flows in from the inlet flow path 112 and the time it is ejected from the outlet flow path 114. This simplifies the structure of the micro-bubble-generating device 100 and makes it possible to reduce the overall size.

[0025] Hereinafter, the operation of spraying the bubble water flow BF containing fine bubbles using the fine bubble generating device 100 according to the first embodiment will be described.

[0026] FIG. 5 is a cross-sectional view showing an outline of the operation of generating fine bubbles using the fine bubble generating device according to the first embodiment.

[0027] As shown in FIG. 5, when a water flow WF having a predetermined water pressure flows into the inlet side (lower surface 122b side) of the swirl flow forming plate 120 of the fine bubble generating device 100, the water flow WF passes through the plurality of inclined holes 124 of the swirl flow forming plate 120, and a swirl flow WF is generated in the inlet flow path 112. ｓ At this time, since the swirl flow forming plate 120 is attached to the housing 110 without any gaps, the water flow WF flows downstream only through the inclined holes 124 of the swirl flow forming plate 120, and as a result, the swirl flow of the water flow WF that has passed through the swirl flow forming plate 120 is in a state where it is more pressurized than when it flowed in.

[0028] Next, the swirling flow WF ｓis guided by an obstacle member 130 disposed in the inlet flow passage 112 and is intentionally disturbed by a plurality of fin members 134. ｄ The inlet OP of the outflow passage 114 ｉｎ By intentionally disrupting the swirling flow in the inlet flow passage 112 with the obstruction member 130, the ability to form fine bubbles in the outlet flow passage 114 can be improved.

[0029] Next, the agitation flow WF flowing into the reduced diameter flow path RC of the outflow path 114 ｄ is gradually compressed while passing through the reduced diameter flow path RC of the outlet flow path 114, and becomes a compressed flow WF ｃ Then, the pressure-reduced flow WF is rapidly reduced while passing through the throttle flow path RP and the enlarged diameter flow path EC. ｒ By going through these stages, countless minute bubbles are formed inside the water flow WF flowing through the outflow passage 114 due to the above-mentioned "cavitation phenomenon," and are sprayed out as a bubble water flow BF.

[0030] 6A and 6B show an outline of a swirl flow forming plate according to a modified example of the embodiment, in which FIG. 6A is a schematic view thereof and FIG. 6B is a side view showing an outline of a water flow formed by the swirl flow forming plate.

[0031] In the fine bubble generating device 100 according to the first embodiment of the present invention, as shown in Fig. 6A, for example, a substantially conical protrusion 128 may be formed in the center of the upper surface 122a of the main body 122 of the swirl flow forming plate 120. With this protrusion 128, as shown in Fig. 6B, for example, the water flow WF flowing in from the right side in the drawing hits the top of the protrusion 128 and becomes branched flows WF1, and these branched flows WF1 smoothly flow into the plurality of inclined holes 124, and the swirl flow WF that has passed through the swirl flow forming plate 120 ｓ The flow rate or volume can be further increased.

[0032] 6 is merely an example, and the diameter of the circle and the height of the conical portion can be freely set. Also, while the protrusion 128 is shown in the figure as a typical cone shape, it may be formed so that the cross section of the conical portion is not only a straight line but also a smooth curve, such as a trumpet shape. Furthermore, guide grooves that guide the branch flow WF1 may be formed on the surface of the conical portion of the protrusion 128 in accordance with the positions of the multiple inclined holes 124 formed in the main body 122.

[0033] By providing the above-described configuration, the micro-bubble generating device according to the present invention has a structure in which the water flow that has passed through the swirl flow generating plate is intentionally disturbed by the obstruction member, and the subsequent flow undergoes cavitation treatment in the outflow flow path, thereby increasing the amount of micro-bubbles generated. For example, when the micro-bubbles contained in the bubbly water flow generated by the micro-bubble generating device according to the present invention were measured using a laser diffraction particle size distribution analyzer, it was confirmed that approximately 700 million ultra-fine bubbles were dispersed per ml (milliliter).

[0034] 1 to 6B according to the first embodiment of the present invention can be applied to, for example, a handheld water-discharging nozzle for general household use, a water supply mechanism in the agricultural, fisheries or industrial fields, etc. Below, as the second embodiment, a configuration example will be described in which the fine-bubble-generating device 100 according to the first embodiment is applied to a water pipe unit that can be incorporated into a general water supply mechanism.

[0035] Figure 7 shows an outline of a water pipe unit according to another representative example of the present invention, Example 2, where Figure 7A is an external view and Figure 7B is a partial cross-sectional view. Figure 8 shows an outline of a water pipe unit according to a modification of Example 2, where Figure 8A is an external view and Figure 8B is a partial cross-sectional view. In Example 2, components that are the same as or common to Example 1 shown in Figures 1 to 6B are designated by the same reference numerals, and repeated description of these components will be omitted.

[0036] As shown in FIG. 7A, the water pipe unit 1 according to the second embodiment of the present invention includes a substantially tubular main body member 10 into which the micro-bubble generating device 100 exemplified in the first embodiment is inserted, an inlet-side connecting member 20 that connects the main body member 10 to an inlet pipe 2 through which a water flow is supplied, and an outlet-side connecting member 30 that connects the main body member 10 to an outlet pipe 3 that discharges the water flow in which micro-bubbles have been formed.

[0037] 7B, the main body member 10 is formed of the same or similar material as the inlet pipe 2 and the outlet pipe 3, and is preferably configured so that its inner diameter is the same as those of the inlet pipe 2 and the outlet pipe 3. In addition, a convex portion 12 is formed on the inner surface of the main body member 10, which functions as a positioning (stopper) when the fine-bubble-generating device 100 is inserted.

[0038] As an example, the inlet-side connecting member 20 and the outlet-side connecting member 30 are configured as annular members made of the same or similar material as the main body member 10. The inner surfaces of the inlet-side connecting member 20 and the outlet-side connecting member 30 are formed with threads for threaded connection with the outer peripheries of the inlet pipe 2 and the outlet pipe 3 near their connection ends.

[0039] 7 illustrates a configuration in which the inlet side connecting member 20 and the outlet side connecting member 30 are fixed to the outer periphery of the main body member 10 near the ends thereof and are screwed to the inlet pipe 2 and the outlet pipe 3, respectively, but they may also be configured as separate members each having threads formed thereon for screwing to the main body member 10. Furthermore, if the inlet pipe 2 or the outlet pipe 3 is made of a rubber hose or the like, the inlet side connecting member 20 or the outlet side connecting member 30 may be configured as a hose joint.

[0040] In the water pipe unit 1 according to the second embodiment of the present invention, as shown in FIG. 8, when a water flow WF is supplied from the flow path C1 inside the inlet pipe 2, the water flow WF passes through the swirl flow forming plate 120 of the fine-bubble generating device 100 arranged inside the main body member 10 and flows into the inlet flow path 112 as a swirl flow, and is intentionally disturbed by the obstacle member 130 arranged inside the inlet flow path 112 to flow into the outlet flow path 114 as an agitated flow.

[0041] Thereafter, when the stirred flow passes through the outlet flow path 114 including the throttle flow path RP, countless tiny bubbles are formed inside due to the "cavitation phenomenon" described above, and are discharged into the flow path C2 of the outlet pipe 3 as a bubble water flow BF.

[0042] Furthermore, the water pipe unit according to the second embodiment of the present invention may be configured to additionally provide an intake mechanism for taking in air or gas into the fine-bubble-generating device 100. For example, as shown in Fig. 8A, a gas supply source 40 is connected via a supply pipe 42 to a main body member 10 in which the fine-bubble-generating device 100 is disposed.

[0043] As shown in FIG. 8B , the supply pipe 42 is connected to a communication flow path 116 formed in the housing 110 of the fine bubble generating device 100, and one end of the communication flow path 116 opens toward the outlet flow path 114. As a result, the compressed flow WF Ｃ The amount of fine bubbles contained in the bubbly water flow BF can be further increased by additionally supplying gas from the gas flow GF supplied from the outside.

[0044] As shown in FIG. 8B, the communication flow path 116 is preferably disposed so as to open near the downstream side of the throttle flow path RP of the outflow flow path 114. Ｃ When the gas flows through the throttle flow passage RP, a negative pressure is generated near the opening of the communication flow passage 116, so that the gas flow GF supplied from the outside can be taken in more quickly and in larger quantities.

[0045] The gas supplied from the external gas supply source 40 is not limited to air, and any gas such as hydrogen, oxygen, carbon dioxide, nitrogen, or fluorine can be used depending on the application or purpose. When air is taken in from the outside, one end of the supply pipe 42 may simply be open to the atmosphere, instead of the gas supply source 40. Furthermore, the liquid flowing through the water pipe unit 1 according to the second embodiment may be not only water or hot water, but also hydrogen water in which hydrogen is dissolved, organic solvents, or the like.

[0046] With the above-described configuration, the water pipe unit according to the second embodiment can apply the bubbly water flow obtained by the fine-bubble generating device according to the first embodiment to handheld water-discharging nozzles for general households, water supply mechanisms in the agricultural, fishing, or industrial fields, and the like.

[0047] The description of the above-described embodiment is merely an example of the fine bubble generating device or water pipe unit according to the present invention, and the present invention is not limited to each embodiment. Furthermore, a person skilled in the art can make various modifications without departing from the spirit of the present invention, and these modifications are not excluded from the scope of the present invention.

[0048] For example, the housing 110 of the micro-bubble generating device 100 is configured as a single, integrally molded member, but instead of being integrally molded, it may be configured to be formed by joining two parts cut along a plane passing through the central axis of the housing 110.

[0049] REFERENCE SIGNS LIST 1 Water pipe unit 10 Main body member 20 Inlet-side connecting member 30 Outlet-side connecting member 100 Fine bubble generating device 110 Housing 112 Inlet flow path 114 Outlet flow path 116 Communication flow path 120 Swirl flow forming plate 122 Main body portion 124 Inclined hole 126 Step portion 128 Projection portion 130 Obstacle member 132 Base member 134 Fin member BF Bubble water flow EC Expanding diameter flow path RC Reducing diameter flow path RP Throttle flow path WF Water flow

Claims

1. A fine-bubble generating device comprising: a substantially cylindrical housing having an inlet flow path and an outlet flow path formed continuously therein; a swirl flow-forming plate having a plurality of inclined holes and attached to the inlet of the inlet flow path; and an obstacle member disposed within the inlet flow path to intentionally disturb the water flow that has passed through the swirl flow-forming plate, wherein the outlet flow path includes a throttle flow path with a small inner diameter in an intermediate region between the inlet and outlet.

2. The microbubble generating device according to claim 1, wherein the obstruction member is composed of a base member formed to contact the inner surface of the inlet flow channel and a plurality of fin members standing upright from the base member.

3. The fine bubble generating device according to claim 1, wherein the housing is constructed as a single, integrally molded member.

4. A water pipe unit comprising an inlet-side connecting member to which a water flow is supplied, a micro-bubble generating device that generates micro-bubbles in the water flow, and an outlet-side connecting member that discharges the water flow in which the micro-bubbles have been formed, wherein the micro-bubble generating device comprises a substantially cylindrical housing having an inlet flow path and an outlet flow path formed continuously therein, a swirl flow forming plate having a plurality of inclined holes and attached to the inlet of the inlet flow path, and an obstruction member that is disposed within the inlet flow path and intentionally disturbs the water flow that has passed through the swirl flow forming plate, and wherein the outlet flow path has a throttle flow path with a small inner diameter formed in an intermediate region between the inlet and outlet.

5. The water pipe unit according to claim 4, wherein the obstruction member is composed of a base member formed to contact the inner surface of the inlet flow path, and a plurality of fin members standing upright from the base member.

6. The water pipe unit according to claim 4, wherein the housing is constructed as a single, integrally molded member.

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