Bubble generator and water supply device with bubble generator

Abstract

To provide a bubble generator with high bubble content in a liquid.SOLUTION: In a bubble generator for mixing air bubbles containing fine air bubbles with a liquid, a generator body 8 comprises an upstream part 6 and a downstream part 7. The generator body 8 comprises: an inflow port 12 for water 2; a pressurizing port 13; a mixing port 22 which mixes air 14 into water 2, has a diameter that is smaller than the inflow port 12 and equal to or larger than the pressurizing port 13; and an outflow port 23 which is the outflow port 23 for water 2 on a downstream side of the mixing port 22, and has a diameter larger than the mixing port 22. A mating part between the upstream part 6 and the downstream part 7 forms a gas inlet for mixing external air 14 into the mixing port 22.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a bubble generator and a water supply device provided with the bubble generator.

Background Art

[0002] Patent Document 1 discloses a fine bubble generator. The fine bubble generator 1 of Patent Document 1 is composed of a cylindrical body 2 and a flange 3, and a through hole 4 is provided at the center of the cylindrical body 2 and the flange 3.

[0003] The through hole 4 is configured such that a liquid (fluid in Patent Document 1) swirls as it progresses through the through hole 4. That is, the through hole 4 has a constricted shape with a narrow center and a widened shape at both ends. In other words, the through hole 4 is formed with a narrow center and wide ends so that the centrifugal force due to the rotation of the liquid becomes larger and the central portion is greatly depressurized.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the fine bubble generator 1 of the above Patent Document 1, although the through hole 4 is formed with a narrow center and wide ends so that the centrifugal force due to the rotation of the liquid becomes larger and the central portion is greatly depressurized, it is pointed out that the bubble content in the liquid is small.

[0006] Therefore, an object of the present invention is to provide a bubble generator in which the bubble content in a liquid is large, and a water supply device provided with the bubble generator.

Means for Solving the Problems

[0007] The present invention relates to a bubble generator for mixing bubbles containing fine bubbles into a liquid, comprising a generator main body part having an upstream part arranged on the upstream side in the direction in which the liquid flows, and a downstream part arranged on the downstream side in the flow direction with respect to the upstream part and combined with the upstream part. The generator main body part includes a liquid inlet, a pressurizing port arranged on the downstream side of the inlet, pressurizing the liquid flowing out from the inlet and having a smaller inner diameter than the inlet, a mixing port arranged on the downstream side of the pressurizing port, mixing gas into the liquid flowing out from the pressurizing port and having an inner diameter smaller than the inlet and equal to or larger than the diameter of the pressurizing port, and an outlet arranged on the downstream side of the mixing port, being an outlet of the liquid flowing out from the mixing port and having a larger inner diameter than the mixing port. The mating part in the combination of the upstream part and the downstream part forms a gas inlet for mixing external gas into the mixing port, which is a bubble generator.

[0008] According to the bubble generator having the above configuration of the present invention, when liquid flows in from the inlet and the liquid is pressurized at the pressurizing port, the flow velocity of the liquid is increased by the Venturi effect, and gas is mixed into the liquid at the mixing port from the gas inlet formed at the mating part of the upstream part and the downstream part. Therefore, a large amount of gas is mixed into the liquid as fine bubbles, and the bubble content in the liquid flowing out from the outlet is improved.

[0009] In the present invention, the configuration may be such that gas amount adjusting means for adjusting the inflow amount of gas is provided at the gas inlet.

[0010] According to the bubble generator having the above configuration, the inflow amount of external gas into the liquid can be adjusted by the gas amount adjusting means.

[0011] In the present invention, the gas amount adjusting means may include a closing part for closing the gap between the upstream part and the downstream part in the mating part, and an opening part for opening the gap.

[0012] According to the bubble generator having the above configuration, the inflow amount of gas can be adjusted by adjusting the size of the gap between the upstream part and the downstream part with the closing part and the opening part.

[0013] In the present invention, the mixing inlet may be configured to have a taper with an inner diameter that becomes smaller from the upstream side to the downstream side.

[0014] According to the bubble generator having the above configuration, the liquid flowing from the pressurizing port has at least part of the liquid pressure released on the upstream side of the mixing inlet, and the liquid is pressurized again by the inner diameter of the taper that becomes smaller toward the downstream side, so that the mixing of gas into the liquid can be promoted while the bubbles are refined.

[0015] In the present invention, the mixing inlet may be configured to have a taper with an inner diameter that becomes larger from the upstream side to the downstream side.

[0016] According to the bubble generator having the above configuration, the liquid flowing from the pressurizing port has the liquid pressure gradually released at the mixing inlet, promoting the mixing of gas into the liquid.

[0017] It is also possible to use a water supply device that utilizes any of the above bubble generators.

Effect of the Invention

[0018] According to the bubble generator and the water supply device equipped with the bubble generator of the present invention, when the liquid is pressurized at the pressurizing port, the flow rate of the liquid is increased by the Venturi effect, and gas is mixed into the liquid from the gas inlet to the mixing inlet. Therefore, a large amount of gas is mixed into the liquid as fine bubbles, so that the bubble content of the liquid flowing out from the outlet can be improved.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0020] The bubble generator according to the embodiment of the present invention will be described with reference to FIGS. 1 to 6. As shown in FIG. 1, the bubble generator 1 according to the present embodiment is used as an example in a shower device 3 which is a water supply device so as to mix bubbles containing fine bubbles into water (liquid) 2. In this case, the bubbles include microbubbles and ultrafine bubbles. Microbubbles are bubbles of 1 μm or more, and those less than that are referred to as ultrafine bubbles.

[0021] As shown in the figure, the location where the bubble generator 1 is disposed is at the connecting portion between the shower head 4 and the shower hose 5, and is housed on the shower head 4 side.

[0022] As shown in FIGS. 1 and 2, the outer contour of the bubble generator 1 is cylindrical, and the bubble generator 1 has a generator main body 8 including an upstream part 6 and a downstream part 7. The generator main body 8 has an upstream end face 6a, a downstream end face 7a, and a through portion (to be described in detail later) formed in the inner diameter portions of the upstream part 6 and the downstream part 7.

[0023] The location of the bubble generator 1 will be described in detail. As shown in Fig. 1, the screw 10 formed at the inflow side end of the main body 9 of the shower head 4 and the connector 5a on the outflow side of the shower hose 5 are configured to be screwed together, and the bubble generator 1 is detachably fitted and accommodated inside the screw 10 of the shower head 4. Inside the inflow side of the main body 9 of the shower head 4, there is a holding step portion 11 for attaching a water-saving device (not shown). By using the holding step portion 11, the downstream end face 7a of the generator main body portion 8 can abut against the inside of the screw 10, and the upstream end face 6a of the generator main body portion 8 is flush with the inflow side end portion 10a of the screw 10. Also, when the screw 10 and the connector 5a are screwed together, the upstream end face 6a can abut against the inner step portion 5b of the connector 5a.

[0024] The entire bubble generator 1 from the upstream end face 6a to the downstream end face 7a is accommodated inside the screw 10 of the main body 9 of the shower head 4. By the downstream end face 7a abutting against the holding step portion 11 of the main body 9 and the upstream end face 6a abutting against the inner step portion 5b of the connector 5a, the flow direction (upstream and downstream direction) of the water 2 in the shower device 3 is positioned.

[0025] Based on Fig. 3, the details of the configuration of the bubble generator 1 will be described.

[0026] [Upstream portion] First, the upstream portion 6 of the generator main body portion 8 will be described. The upstream portion 6 has an upstream body portion 6A, an inlet 12 and a pressurizing port 13 as the through portions formed inside the upstream body portion 6A, and a first trap 15 for taking in air 14 into the generator main body portion 8. The upstream outer diameter surface 16 of the upstream body portion 6A has a cylindrical shape with a uniform diameter in the flow direction. The inlet 12 and the pressurizing port 13 penetrate through the central portion in the radial direction of the upstream body portion 6A so as to communicate with each other.

[0027] The inlet 12 has an inlet port 17 and a throttle port 18 (buffer section). The inlet port 17 has the upstream end face 6a of the upstream section 6 as an opening. The inlet port 17 is formed in a direction perpendicular to the flow of the water 2, and is formed to introduce the water 2 in the shower hose 5 (see FIG. 1). The inner diameter surface 17a of the inlet port 17 has a cylindrical shape with a uniform diameter (dimension D1 in FIG. 3) in the flow direction. The throttle port 18 is arranged to communicate with the downstream side of the inlet port 17. The inner diameter surface 18a of the throttle port 18 has a frustum shape with a narrowed downstream side and is formed in a tapered shape. Note that the inner diameter on the upstream side of the throttle port 18 is the same as the inner diameter of the inlet port 17. Also, the lengths of the inlet port 17 and the throttle port 18 in the flow direction are made substantially equal.

[0028] The pressurizing port 13 is connected so as to communicate with the central downstream side of the throttle port 18. The inner diameter surface 13a of the pressurizing port 13 has a cylindrical shape with a uniform diameter (dimension D2 in FIG. 3) in the flow direction. That is, the inner diameter of the pressurizing port 13 is the same as the inner diameter of the downstream end of the throttle port 18. The pressurizing port 13 has an inner diameter smaller than the inner diameter of the inlet 12, and is a through portion for accelerating the flow velocity from the inlet 12 (for generating a differential pressure). The length of the pressurizing port 13 in the flow direction is 1.5 times the diameter of the pressurizing port 13.

[0029] As shown in FIG. 3, the first trap 15 is a structure for taking in gas, that is, air 14, into the generator main body 8 in combination with the second trap 19 formed in the downstream section 7.

[0030] Based on FIGS. 3 and 4, the first trap 15 will be described. The first trap 15 is a peripheral portion around the pressurizing port 13 and has an annular recess 20 directed upstream. In other words, the pressurizing port 13 is arranged at the central position of the recess 20. The recess 20 has a bottom surface 20a on the upstream side, an inner surface 20b on the side of the pressurizing port 13, and an outer surface 20c on the side of the outer diameter surface 16 of the upstream section.

[0031] The bottom surface 20a is formed as an annular surface parallel to the upstream end face 6a. This bottom surface 20a is a plane perpendicular to the central axis C (the radial center of the generator main body 8) in the flow direction of the pressurizing port 13, and is arranged between the upstream end and the downstream end of the pressurizing port 13. The inner surface 20b is formed as a frustum of a cone-shaped surface that tapers and contracts toward the downstream side with respect to the central axis C. This tapered shape narrows toward the downstream side when viewed as a frustum of a cone in Fig. 3, but widens toward the downstream side when viewed from the recess 20 itself. The downstream end of this inner surface 20b is continuously formed with a downstream surface 13b that is parallel to the upstream end face 6a of the upstream portion 6 (pressurizing port 13). This downstream surface 13b is an annular surface with respect to the central axis C and is arranged on the downstream end side in the flow direction of the pressurizing port 13. The outer surface 20c is parallel to the central axis C and is formed parallel to the outer diameter surface 16 of the upstream portion. The downstream end of the outer surface 20c extends downstream from the downstream surface 13b of the pressurizing port 13 and is an extended surface 6b formed parallel to the upstream end face 6a. The extended surface 6b is an annular surface perpendicular to the central axis C. Also, the extension difference between the downstream surface 13b and the extended surface 6b is represented by the dimension L in Fig. 4.

[0032] [Downstream portion] Next, the downstream portion 7 of the generator main body 8 will be described. As shown in Figs. 3 and 5, the downstream portion 7 includes a downstream portion body 21, an inlet 22 and an outlet 23 as the through portions, and a second trap 19.

[0033] The outer diameter surface 21a of the downstream portion of the downstream portion body 21 is, like the outer diameter surface 16 of the upstream portion of the upstream portion body 6A, a cylindrical shape with a uniform outer diameter in the flow direction. The inlet 22 and the outlet 23 arranged downstream of the inlet 22 penetrate through the central portion in the radial direction of the downstream portion body 21.

[0034] The inlet 22 has an upstream inlet 24 on the upstream side and a downstream inlet 25 on the downstream side that communicates with the upstream inlet 24. The upstream inlet 24 is open on the upstream side and communicates with the pressurizing port 13. The inner diameter surface 25a of the downstream inlet 25 has a cylindrical shape with a uniform diameter (dimension D3 in Fig. 3) along the lower end of the inner diameter surface of the upstream inlet 24 in the flow direction.

[0035] The inner diameter surface 24a of the upstream mixing inlet 24 is formed to have a larger diameter than the pressure port 13, and is formed in a frustum-shaped surface that tapers and narrows towards the downstream side.

[0036] The diameter of the upstream side and the diameter of the downstream side of the mixing inlet 22, which are formed in a tapered shape, are both formed to have a larger diameter than the pressure port 13. That is, D1 > the diameter of the upstream mixing inlet 24 > D2, and D1 > the diameter D3 of the downstream mixing inlet 25 > D2. Note that the length of the upstream mixing inlet 24 in the flow direction is formed longer than the length of the downstream mixing inlet 25.

[0037] The outlet 23 has an upstream outlet 26 on the upstream side (the mixing inlet 22 side) and a downstream outlet 27 arranged to communicate with the downstream side of the upstream outlet 26. The upstream outlet 26 communicates with the downstream mixing inlet 25. The inner diameter surface 26a of the upstream outlet 26 is formed in a frustum-shaped surface that expands towards the downstream side from the lower end of the inner diameter surface of the downstream mixing inlet 25 and is formed in a tapered shape. Also, the inner diameter surface 27a of the downstream outlet 27 has a cylindrical shape with a uniform diameter (dimension D4 in FIG. 3) in the flow direction along the lower end of the inner diameter surface of the upstream outlet 26. Note that the downstream outlet 27 is also referred to as a trumpet port.

[0038] Regarding the tapered upstream and downstream diameters of the outlet 23, the diameter of the upstream end side is the same as the diameter of the downstream mixing inlet 25. Also, the tapered downstream diameter of the outlet 23 is formed to have a larger diameter than D1. Alternatively, the tapered downstream diameter of the outlet 23 is formed to have a diameter equal to D1. That is, D1 ≤ D4. Note that the lengths of the mixing inlet 22 and the outlet 23 in the flow direction are formed to be substantially equal.

[0039] As shown in FIG. 3, the second trap 19 is a structure for taking in air 14 into the generator main body 8 in combination with the first trap 15 formed in the upstream portion 6. The second trap 19 includes a convex portion 28 that fits into the concave portion 20 of the first trap 15. The convex portion 28 is annularly arranged in the outer peripheral region of the upstream mixing inlet 24. Note that in the present embodiment, the convex portion 28 is formed in a trapezoidal cross-sectional shape so as to correspond to the concave portion 20.

[0040] As shown in Fig. 5, the convex portion 28 has an upper surface 28a facing the bottom surface 20a of the concave portion 20 in the upstream-downstream direction, an inner opposing surface 28b facing the inner surface 20b in the radial direction, and an outer opposing surface 28c facing the outer surface 20c in the radial direction. The upper surface 28a is a surface parallel to the end surface 7a of the downstream portion and is an annular surface perpendicular to the central axis C. The inner opposing surface 28b is the same as the inclination of the inner diameter surface 24a of the upstream mixing inlet 24. Further, in the combination of the upstream portion 6 and the downstream portion 7, the inner opposing surface 28b and the inner surface 20b are arranged so as to be along each other, and with this configuration, the downstream surface 13b of the pressure port 13 is arranged in the middle of the flow direction of the upstream mixing inlet 24. The outer opposing surface 28c is a surface parallel to the outer diameter surface 21a of the downstream portion of the downstream portion body 21 and is also parallel to the central axis C. On the downstream outer side of the outer opposing surface 28c, an extended opposing surface 21b which is a surface parallel to the end surface 7a of the downstream portion and faces the extended surface 6b is formed. The extended opposing surface 21b is an annular surface perpendicular to the central axis C.

[0041] Here, the relationships of the inner diameter surfaces and the like of the generator main body portion 8 provided with the upstream portion 6 and the downstream portion 7 will be described collectively.

[0042] The inlet 17 at the inlet 12 has a diameter D1 of the cylindrical inner diameter surface 17a, the throttle port 18 has a tapered inner diameter surface 18a, and the pressure port 13 has a diameter D2 of the cylindrical inner diameter surface 13a. And the diameter D2 of the inner diameter surface 13a of the pressure port 13 is set smaller than the diameter D1 of the inner diameter surface 17a of the inlet 12.

[0043] The throttle port 18 is arranged between the inlet 17 and the pressure port 13, the upstream end of the inner diameter surface 18a of the throttle port 18 communicates with the inlet 17, and the downstream end of the inner diameter surface 18a of the throttle port 18 communicates with the pressure port 13. And the upstream mixing inlet 24 at the mixing inlet 22 has a tapered inner diameter surface 24a, and the diameter of this inner diameter surface 24a is set larger than the diameter D2 of the inner diameter surface 13a of the pressure port 13. Note that a downstream surface 13b is provided on the downstream end side in the flow direction of the pressure port 13, and a stepped portion (with a step) is formed on the downstream end side in the flow direction of the pressure port 13 and the downstream surface 13b.

[0044] Also, the tapered inner diameter surface 24a of the upstream mixing inlet 24 has a greater inclination than the tapered inner diameter surface 18a of the throttle port 18. However, with respect to the central axis C, the inner diameter surface 18a of the throttle port 18 has a larger tapered surface than the inner diameter surface 24a of the upstream mixing inlet 24. Further, the outlet 23 is communicated with the pressure port 13 via the mixing inlet 22, and a downstream outlet 27 called a trumpet port is communicated with the downstream side of the outlet 23.

[0045] At the mixing inlet 22, the diameter of the inner diameter surface 24a of the upstream mixing inlet 24 close to the pressure port 13 is set larger than the diameter D3 of the inner diameter surface 25a of the downstream mixing inlet 25 away from the pressure port 13. Also, the diameter D3 of the inner diameter surface 25a of the downstream mixing inlet 25 of the mixing inlet 22 is larger than the diameter D2 of the inner diameter surface 13a of the pressure port 13, and the diameter D3 of the inner diameter surface 25a of the downstream mixing inlet 25 of the mixing inlet 22 is set smaller than the diameter D1 of the inner diameter surface 17a of the inlet 17 of the inlet 12.

[0046] Regarding the diameter D1 of the inner diameter surface 17a of the inlet 17 at the inlet 12 and the diameter D4 of the inner diameter surface 27a of the downstream outlet 27 of the outlet 23, the diameter D4 of the inner diameter surface 27a of the downstream outlet 27 is set larger than the diameter D1 of the inner diameter surface 17a of the inlet 17.

[0047] The diameter D3 of the inner diameter surface 25a of the downstream mixing inlet 25 of the mixing inlet 22 is set to be 1.2 to 2.0 times the diameter D2 of the inner diameter surface 13a of the pressure port 13. Specifically, when the diameter D2 of the inner diameter surface 13a of the pressure port 13 is 3 mm, the diameter D3 of the inner diameter surface 25a of the downstream mixing inlet 25 of the mixing inlet 22 is 3.5 mm.

[0048] Note that the tapered inner diameter surface 24a of the upstream mixing inlet 24 and the tapered inner diameter surface 26a of the upstream outlet 26 have opposite inclinations, and the tapered inner diameter surface 24a of the upstream mixing inlet 24 has a greater inclination than the tapered inner diameter surface 26a of the upstream outlet 26. However, with respect to the central axis C, the tapered inner diameter surface 26a of the upstream outlet 26 has a larger tapered surface than the tapered inner diameter surface 24a of the upstream mixing inlet 24.

[0049] The relationships of the inner diameter surfaces and the like of the generator main body 8 including the upstream portion 6 and the downstream portion 7 have been collectively described above.

[0050] Here, by the combination of the first trap 15 and the second trap 19, a mating portion in the combination of the upstream portion 6 and the downstream portion 7 is formed. The space between the inner opposing surface 28b and the inner surface 20b (outside the diameter of the pressure port 13) is taken as the air inflow portion P, and the air 14 is sent from the inflow portion P to the upstream side mixing port 24. That is, the bottom surface 20a and the upper surface 28a, the extension surface 6b and the extension opposing surface 21b, the outer surface 20c and the outer opposing surface 28c, and the inner surface 20b and the inner opposing surface 28b, which are the mating portions of the first trap 15 and the second trap 19 constituting the combination of the upstream portion 6 and the downstream portion 7, are gas inlets for mixing the air 14 from the outside of the diameter (outside) into the mixing port 22, that is, into the inside of the diameter of the generator main body 8 when the water 2 flows through the inlet 12, the pressure port 13, the mixing port 22, and the outlet 23.

[0051] In the first trap 15 and the second trap 19, as shown in FIG. 5, gaps δ1, δ2, and δ3 are respectively formed between the extension surface 6b and the extension opposing surface 21b, between the outer surface 20c and the outer opposing surface 28c, and between the inner surface 20b and the inner opposing surface 28b. That is, the spaces between the extension surface 6b and the extension opposing surface 21b, between the outer surface 20c and the outer opposing surface 28c, and between the inner surface 20b and the inner opposing surface 28b are open portions. On the other hand, in the state where the upstream portion 6 and the downstream portion 7 are combined, the bottom surface 20a and the upper surface 28a are closed. In other words, the space between the bottom surface 20a and the upper surface 28a is closed. Note that the gaps δ1, δ2, and δ3 are the same gap.

[0052] That is, when water 2 flows into the inlet 12, the pressure port 13, the mixing port 22, and the outlet 23, the junction of the first trap 15 and the second trap 19 is configured as a means for adjusting the amount of air introduced from the outside of the diameter into the mixing port 22. As described above, when water 2 flows, air 14 from the outside of the diameter is introduced through the gap δ1 between the extension surface 6b, which is the open part, and the extension opposing surface 21b, and when it reaches the gap δ2 between the outer surface 20c and the outer opposing surface 28c, the closed bottom surface 20a and the upper surface 28a are opened by the pressure of water 2. Further, when it reaches the gap δ3 between the inner surface 20b and the inner opposing surface 28b, the air 14 reaches the inflow portion P of the upstream mixing port 24.

[0053] At this time, the downstream end of the outer surface 20c extends downstream of the downstream surface 13b of the pressure port 13 as represented by the L dimension in FIG. 4 and becomes the extension surface 6b. That is, the gap δ1 between the extension surface 6b and the extension opposing surface 21b extends downstream of the inflow portion P of the air 14 in the upstream mixing port 24.

[0054] Also, in order for the bottom surface 20a and the upper surface 28a to be opened, a slight margin is provided between the holding step portion 11 with which the downstream end surface 7a of the bubble generator 1 can come into contact and the inner step portion 5b of the connector 5a with which the upstream end surface 6a of the bubble generator 1 can come into contact. With this configuration, by separating the upstream portion 6 and the downstream portion 7 in the flow direction (upstream and downstream sides), the amount of air 14 flowing into the inflow portion P of the air 14 is adjusted.

[0055] With the configuration of the above-described air volume adjusting means, the generator main body portion 8 is incorporated inside the screw 10 of the shower head 4, the connector 5a of the shower hose 5 is screwed into the screw 10 of the shower head 4, water 2 flows through the through portion, that is, the inlet 12, the pressure port 13, the mixing port 22, and the outlet 23, and air 14 from the outside of the diameter is introduced through the gap δ1 between the extension surface 6b, which is the open part, and the extension opposing surface 21b. When it reaches the gap δ2 between the outer surface 20c and the outer opposing surface 28c, the closed bottom surface 20a and the upper surface 28a are opened. Further, when it reaches the gap δ3 between the inner surface 20b and the inner opposing surface 28b, the air 14 reaches the inflow portion P of the upstream mixing port 24.

[0056] Then, when water 2 flows in from the inlet 12 and is pressurized at the pressure port 13, the flow velocity of water 2 is increased by the Venturi effect, and air 14 is mixed into the water 2 in the mixing port 22 from the gas inlet formed at the junction of the upstream part 6, the first trap 15, and the second trap 19 in the downstream part 7. As a result, a large amount of air 14 is mixed into the water 2 as fine bubbles.

[0057] In the first embodiment of the present invention, a first trap 15 is formed at the downstream end of the upstream part 6, a second trap 19 is formed at the upstream end of the downstream part 7, the first trap 15 and the second trap 19 are combined to form a junction, and a passage through which gas (air 14) flows from the outside diameter to the inside diameter is formed between the first trap 15 and the second trap 19. In this case, the passage is the extended surface 6b and the extended opposing surface 21b, the outer surface 20c and the outer opposing surface 28c, the bottom surface 20a and the top surface 28a, and the inner surface 20b and the inner opposing surface 28b. Further, an outlet (inflow portion P) of the passage is formed between the pressure port 13 and the mixing port 22. Furthermore, the inner diameter D3 inside the downstream of the pressure port 13 is formed smaller than the upstream inner diameter of the mixing port 22, and the inside of the downstream of the pressure port 13 and the upstream inner diameter of the mixing port 22 are communicated by a stepped portion, in this case, the downstream surface 13b, and an outlet is formed in the stepped portion.

[0058] According to such a bubble generator 1, the pressure of the water 2 flowing from the pressure port 13 is released on the upstream side of the inner diameter surface 24a of the mixing port 22, which is wider than the inner diameter surface 13a of the pressure port 13, and the water 2 is pressurized again by the inner diameter surfaces 24a and 25a, thereby promoting the mixing of air 14 and enabling the bubbles to be refined. Therefore, the content of fine bubbles, that is, microbubbles and ultrafine bubbles, in the water 2 flowing out from the outlet 23 can be improved.

[0059] Furthermore, since the bubble generator 1 of the present embodiment simply combines the cylindrical upstream part 6 and the downstream part 7, the manufacturing cost is also low. Also, since the upstream part 6 and the downstream part 7 are simply combined, it is easy to assemble them to the shower head 4.

[0060] The present invention is not limited to the above-described embodiments. In the above-described embodiments, the inner diameter surface 24a of the upstream mixing inlet 24 is tapered, and the inner diameter surface 25a of the downstream mixing inlet 25 has a cylindrical shape with a uniform diameter in the flow direction. However, as shown in the second embodiment of FIG. 6, the inner diameter surface 24a of the upstream mixing inlet 24 and the inner diameter surface 25a of the downstream mixing inlet 25 can also have a cylindrical shape with a uniform diameter in the flow direction, as shown by the solid line in FIG. 6. In this case, the inner diameter surface 24a of the upstream mixing inlet 24 and the inner diameter surface 25a of the downstream mixing inlet 25 have the same diameter as the inner diameter surface 13a of the pressurizing port 13.

[0061] Further, in the above-described first embodiment, the convex portion 28 was formed in a trapezoidal cross-section, but as shown in FIG. 6, it can also be formed in a rectangular cross-section. In this case, the concave portion 20 has a rectangular cross-section corresponding to the convex portion 28. Also, a gap δ4, which is an open portion, is formed between the downstream surface 13b of the upstream portion 6 and the upstream surface 7b of the downstream portion 7. This gap δ4 is the same as the gaps δ1 to δ3. Other configurations are the same as those in the first embodiment.

[0062] In the second embodiment, the inner diameter surface 24a of the upstream mixing inlet 24 and the inner diameter surface 25a of the downstream mixing inlet 25 have a cylindrical shape with a uniform diameter in the flow direction. However, the mixing inlet 22 may be configured such that the upstream end has the same diameter as the pressurizing port 13, and the inner diameter surface 25a of the downstream mixing inlet 25 is tapered so as to have a larger diameter from the upstream side to the downstream side, as shown by the two-dot chain line in FIG. 6. And the inner diameter surface 26a of the upstream outlet 26 may be configured to continue with a different taper angle on the inner diameter surface 25a of the downstream mixing inlet 25. In this case, the taper inclination of the inner diameter surface 25a of the downstream mixing inlet 25 is larger than the taper inclination of the inner diameter surface 26a of the upstream outlet 26. However, with respect to the central axis C, the inner diameter surface 26a is larger than the inner diameter surface 25a.

[0063] According to this bubble generator 1, the water 2 flowing from the pressure port 13 can gradually release the pressure of the water 2 at the mixing port 13, thereby promoting the mixing of the air 14. In this case, the inflow portion P is formed in the vicinity of the portion where the downstream inner diameter of the pressure port 13 communicates with the upstream inner diameter of the mixing port 22.

[0064] In the above embodiment, the gaps δ1, δ2, δ3, δ4 are the same gaps. However, by changing the gaps δ1, δ2, δ3, δ4, it is also possible to provide a means for adjusting the amount of air introduced from outside the diameter into the mixing port 22.

[0065] In the above embodiment, regarding the diameter D1 of the inner diameter surface 17a of the inlet 17 at the inlet 12 and the diameter D4 of the inner diameter surface 27a of the downstream outlet 27 of the outlet 23, the diameter D4 of the inner diameter surface 27a of the downstream outlet 27 is set larger than the diameter D1 of the inner diameter surface 17a of the inlet 17. However, D1 and D4 may have the same dimensions.

[0066] In the above embodiment, the inflow portion P of the air 14 is in the vicinity of the gap δ3 between the inner surface 20b and the inner opposing surface 28b. However, a configuration may be adopted in which the upstream portion 6 is provided with an inlet 12, a pressure port 13, and an upstream mixing port, and this upstream mixing port can have a cylindrical shape with a uniform diameter in the flow direction. Also, a configuration may be adopted in which the downstream portion 7 is provided with a downstream mixing port and an outlet 23, and this downstream mixing port communicates with the upstream mixing port and can be formed in a frustum shape that tapers in the flow direction. In this case, the upstream mixing port of the upstream portion 6 and the downstream mixing port of the downstream portion 7 are combined, and the air 14 flows in from the combined portion.

[0067] In the above embodiment, the means for adjusting the amount of air is configured such that the combined portion of the first trap 15 and the second trap 19 introduces the air 14 from outside the diameter into the mixing port 22 (inside the diameter of the generator main body portion 8). However, the means for adjusting the amount of air is not limited to the above embodiment. For example, a configuration may be adopted in which grooves along the radial direction are formed at predetermined intervals in the circumferential direction of the bottom surface 20a of the concave portion 20 of the above embodiment, and the bottom surface 20a and the upper surface 28a are opposed to each other.

[0068] Further, in the above embodiment, the concave portion 20 is formed in the upstream portion 6 and the convex portion 28 is formed in the downstream portion 7. However, it is also possible to form a flat surface without the concave portion 20 in the upstream portion 6 and without the convex portion 28 in the downstream portion 7, and in this flat surface, for example, in the flat surface of the downstream portion 7, grooves along the radial direction are formed at predetermined intervals in the circumferential direction. Conversely, it is also possible to form a configuration in which, for example, in the flat surface of the upstream portion 6 of this flat surface, grooves along the radial direction are formed at predetermined intervals in the circumferential direction. Further, in any of the flat surfaces of the upstream portion 6 and the downstream portion 7 of this flat surface, grooves along the radial direction that do not fit in the flow direction can be formed at predetermined intervals in the circumferential direction. Furthermore, it is possible to form a flat surface without the concave portion 20 in the upstream portion 6 and without the convex portion 28 in the downstream portion 7, and configure the two flat surfaces to be connected via a C-ring. In this case, the C-ring may be one in which a part of the circumferential direction is cut out, or it may be configured such that the upstream side portion, or the downstream side portion, or the upstream side portion and the downstream side portion of the C-ring cross-section are inserted in the radial direction without cutting out a part of the circumferential direction.

[0069] In the above embodiment, the outer opposing surface 28c of the upstream portion 6 and the outer surface 20c of the downstream portion 7 are surfaces that fit with a gap δ2 therebetween, but it is also possible to form screws that screw into each other on the outer opposing surface 28c and the outer surface 20c, and introduce air 14 into the interior from the gap between the screws.

[0070] In the above embodiment, the bubble generator 1 has been described as an example used in the shower device 3 which is a water supply device. However, the bubble generator of the present invention can also be used for bathing by attaching it to the facilities attached to a faucet for tap water. Further, since fine bubbles (microbubbles, ultrafine bubbles) have excellent sterilization functions, they can also be used in medical sterilization, purification of wastewater treatment, washing of vegetables, aquaculture, agriculture, forestry, etc.

Explanation of reference numerals

[0071] 1: Bubble generator, 2: Water, 3: Shower device, 4: Shower head, 5: Shower hose, 5a: Connector, 5b: Inner stepped portion, 6: Upstream portion, 6A: Upstream portion body, 6a: Upstream portion end face, 6b: Extension face, 7: Downstream portion, 7a: Downstream portion end face, 7b: Upstream face, 8: Generator main body portion, 9: Main body, 10a: Inlet side end portion, 11: Holding stepped portion, 12: Inlet, 13: Pressure port, 13a: Inner diameter surface, 13b: Downstream surface, 14: Air, 15: First trap, 16: Upstream portion outer diameter surface, 17: Inlet, 17a: Inner diameter surface, 18: Throttle port, 18a: Inner diameter surface, 19: Second trap, 20: Recess, 20a: Bottom face, 20b: Inner face, 20c: Outer face, 21: Downstream portion body, 21a: Downstream portion outer diameter surface, 21b: Extension opposing face, 22: Mixing inlet, 23: Outlet, 24: Upstream side mixing inlet, 24a: Inner diameter surface, 25: Downstream side mixing inlet, 25a: Inner diameter surface, 26: Upstream side outlet, 26a: Inner diameter surface, 27: Downstream side outlet, 27a: Inner diameter surface, 28: Protrusion, 28a: Upper face, 28b: Inner opposing face, 28c: Outer opposing face, C: Central axis, P: Inlet portion, δ1: Gap, δ2: Gap, δ3: Gap

Claims

1. A bubble generator for mixing bubbles containing fine bubbles into a liquid, comprising: an upstream part disposed on the upstream side in the direction of the liquid flow, and a downstream part disposed on the downstream side in the flow direction with respect to the upstream part and combined with the upstream part, the generator main body part being provided with; the generator main body part is: a liquid inlet; a pressurizing port disposed on the downstream side of the inlet, pressurizing the liquid flowing out of the inlet, and having an inner diameter smaller than that of the inlet; a mixing port disposed on the downstream side of the pressurizing port, mixing gas into the liquid flowing out of the pressurizing port, and having an inner diameter smaller than that of the inlet and equal to or larger than that of the pressurizing port; a liquid outlet disposed on the downstream side of the mixing port, which is an outlet of the liquid flowing out of the mixing port and has an inner diameter larger than that of the mixing port; A bubble generator, characterized in that a mating part in the combination of the upstream part and the downstream part forms a gas inlet for mixing external gas into the mixing port.

2. The bubble generator according to claim 1, wherein gas amount adjusting means for adjusting the inflow amount of gas is provided at the gas inlet.

3. The bubble generator according to claim 2, wherein the gas amount adjusting means includes a closing part for closing a gap between the upstream part and the downstream part in the mating part, and an opening part for opening the gap.

4. The bubble generator according to claim 1, wherein the mixing port has a taper with an inner diameter decreasing from the upstream side to the downstream side.

5. The bubble generator according to claim 1, wherein the mixing port has a taper with an inner diameter increasing from the upstream side to the downstream side.

6. A water supply device provided with the bubble generator according to any one of claims 1 to 5.

Images