JP5807783B2 - Fine bubble generator and swirl flow forming body - Google Patents

Description

  The present invention relates to a fine bubble generator that performs gas-liquid mixing using a swirl flow to generate fine bubbles in a liquid.

  A gas-liquid two-phase high-speed swirling method is known as a method for generating fine bubbles such as microbubbles in a liquid. In the gas-liquid two-phase high-speed swirling method, the liquid is swung at high speed along the cylindrical surface in the nozzle to generate a negative pressure at the center of the nozzle (along the axis). Then, gas is introduced into the nozzle by this negative pressure to form a gas-liquid two-phase swirl flow that swirls at high speed. The swirling flow is contracted along the axis and released from the nozzle outlet to shear the gas-liquid two-phase fluid to generate fine bubbles (see, for example, Patent Document 1).

  In the fine bubble generating device of Patent Document 1, high-pressure liquid is guided to a gas-liquid mixing space in a nozzle through a spiral liquid introduction path, whereby a spiral high-speed swirling flow along a cylindrical inner peripheral surface of the gas-liquid mixing space. Form. The spiral liquid introduction path is formed by fitting a cylindrical central solid portion having a spiral blade provided on the outer periphery thereof to the cylindrical portion of the nozzle body.

  The liquid is guided to the spiral liquid introduction path through the liquid introduction path provided above the central solid portion. On the other hand, since the gas is supplied through a pipe connected to a vent hole formed along the central axis of the central solid portion, the pipe is disposed in the liquid introduction path. The liquid introduction path and the gas introduction path need to be separated, but this is achieved by bending the liquid introduction path at a substantially right angle by moving the pipe straight because of problems such as assembly of the pipe.

JP 2008-114205 A

  However, in the configuration of Patent Document 1, since the liquid introduction path is bent at a substantially right angle, pressure loss occurs in this portion, which is disadvantageous for liquid supply at high pressure. In addition, it is necessary to provide a seal structure for preventing leakage of high-pressure liquid in a portion where the straight pipe passes through the wall surface of the liquid introduction path, and processing and parts for that are required. Furthermore, since the central solid part cannot be assembled through the liquid introduction path if the liquid introduction path is bent, the nozzle body has a distal end part where the central solid part is fitted and a base end part where the bent liquid introduction path is formed. Need to be separated.

  An object of the present invention is to provide a fine bubble generating apparatus using a gas-liquid two-phase high-speed swirling method with reduced liquid pressure loss and a small number of parts.

  The swirling passage forming body of the present invention supplies a liquid pressurized through a spiral passage to the gas-liquid mixing space in the nozzle to generate a swirling flow, and uses the negative pressure generated by the swirling flow to supply gas to the gas-liquid mixing space. The gas-liquid two-phase swirl flow is formed by introducing the gas-liquid two-phase swirl flow from the nozzle, and the gas-liquid two-phase fluid is sheared to generate fine bubbles. A passage forming body, a main body having a cylindrical portion, an outer peripheral portion having a cylindrical inner peripheral surface coaxial with the cylindrical portion, a spiral slope formed between the main body and the outer peripheral portion, and a starting end portion of the spiral slope A thick part communicating between the cylindrical part and the outer peripheral part, a first gas passage formed along the central axis of the cylindrical part, and the first gas passage passing through the thick part to the outside of the outer peripheral part And a second gas passage.

  The outer peripheral portion preferably has a cylindrical outer peripheral surface, a pair of annular protrusions are formed along the circumferential direction of the outer peripheral surface, and an opening of the second gas passage is formed between the pair of annular protrusions. It is preferred that In order to form a stable swirl flow, it is preferable to provide a plurality of spiral slopes. From the viewpoint of injection molding, it is preferable that the plurality of spiral slopes do not overlap in the central axis direction. Also, the starting end of the spiral slope on the outer peripheral cylindrical inner surface is raised up to the axial direction, and a beam portion for positioning the tube extending along the cylindrical axis, for example, is formed at a position corresponding to the starting end. Is done.

  The fine bubble generating device of the present invention is a fine bubble generating device to which the swirl flow forming body is mounted, wherein a lateral hole is provided in a swirl flow forming body accommodating space into which the swirl flow forming body is inserted, and the swirl flow forming body is provided. At the time of mounting, the lateral hole is connected to the second gas passage.

  The outer peripheral portion of the swirl flow forming body preferably has a cylindrical outer peripheral surface, a pair of annular projections are formed along the circumferential direction of the outer peripheral surface, and the opening of the second gas passage is a pair of annular projections Preferably, the horizontal hole is formed between the pair of annular projections. As a result, a gas passage is formed between the annular protrusions, and the position of the swirling flow forming body in the rotational direction and the position of the lateral hole can be arbitrarily set. Further, O-rings are respectively disposed adjacent to the annular projections outside the annular space formed by being sandwiched between the pair of annular projections.

  According to the present invention, it is possible to provide a fine bubble generating device using a gas-liquid two-phase high-speed swirling method with reduced liquid pressure loss and a small number of parts.

It is a fragmentary sectional view of the fine bubble generator of this embodiment. It is a side view of the swirl flow formation body of this embodiment. It is a top view of a swirl flow formation body. FIG. 4 is a cross-sectional view of a swirl flow forming body taken along line IV-IV in FIG. 3. It is a fragmentary sectional view of the swirl flow formation body along the VV line of FIG. It is sectional drawing of the swirl | vortex flow formation body along the VI-VI line of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partial cross-sectional view showing a configuration of a fine bubble generating apparatus according to an embodiment of the present invention.

  The main body 11 of the microbubble generator 10 is provided with, for example, a hole 12 that passes vertically along the X1 axis of FIG. The hole 12 is provided with a lateral hole 13 communicating with the outside of the main body 11 along the Y axis orthogonal to the X1 axis, for example. The horizontal hole 13 is provided with a hole 14 that communicates with the outside of the main body 11 along the X2 axis orthogonal to the Y axis. In this embodiment, the X1 and X2 axes are arranged in parallel, but the present invention is not limited to this, and the X1 and X2 axes may be in a twisted relationship.

  One end of the hole 12 (left side in FIG. 1) forms a gas-liquid mixing space 16 of the nozzle 15 of the fine bubble generating device 10. The gas-liquid mixing space 16 is configured as, for example, a cylindrical space, and the tip opening has a shape that is once reduced in diameter and then expanded in diameter. As will be described later, a high-pressure liquid is jetted into the gas-liquid mixing space 16 along its inner peripheral surface, and the liquid moves toward the nozzle tip while swirling at a high speed. A negative pressure along the X1 axis is generated by the high-speed swirling flow at the center of the gas-liquid mixing space 16, and a gas induced by the negative pressure is supplied to the gas-liquid mixing space 16, and the gas-liquid two-phase swirling flow Is formed. The gas-liquid two-phase swirl flow is ejected from the tip of the nozzle 15, and the gas-liquid two-phase fluid is sheared and fine bubbles are generated.

  On the other hand, a liquid supply unit 17 is provided at the other end of the hole 12 (on the side opposite to the nozzle 15). The liquid supply part 17 is a part for supplying the liquid described above into the hole 12 from the outside. In the present embodiment, the liquid is supplied using, for example, a flexible tube (not shown), and a tube joint such as a push-in joint is used for the liquid supply unit 17. The liquid may be supplied through a pipe, and various well-known fluid couplings can be used for the coupling depending on the purpose and use conditions.

  In the hole 12, for example, a cylindrical swirl flow forming body accommodation space 19 for accommodating the swirl flow forming body 18 is provided between the nozzle 15 and the liquid supply unit 17. The inner diameter of the swirl flow forming body accommodating space 19 is larger than the inner diameter of the gas-liquid mixing space 16, and both spaces are connected by a truncated cone space 20 having a truncated cone shape.

  The swirl flow forming body 18 is a member for ejecting the high-pressure liquid supplied from the liquid supply unit 17 along the inner periphery of the gas-liquid mixing space 16 and guiding the gas to the center of the gas-liquid mixing space 16. And a main body 180 disposed in the center, and an outer peripheral portion 181 having, for example, a substantially cylindrical shape surrounding the periphery. The main body 180 is composed of a truncated cone-shaped trapezoidal part 183 that extends coaxially with the cylindrical part 182. That is, when the swirl flow forming body 18 is disposed in the swirl flow forming body accommodation space 19, the trapezoidal portion 183 extends into the frustoconical space 20, and the outer peripheral surface of the trapezoidal portion 183 and the inner peripheral surface of the frustoconical space 20. A gap is formed between them.

  The inner diameter of the swirl flow forming body accommodating space 19 is larger than the inner diameter of the trapezoidal bottom surface of the frustoconical space 20, and a stepped portion 21 is formed at the connecting portion of both the spaces 19 and 20. That is, when the swirling flow forming body 18 is inserted into the hole 12 from the liquid supply unit 17 side during assembly, the tip of the outer peripheral portion 181 comes into contact with the stepped portion 21 when the swirling flow forming body 18 reaches an appropriate position. The movement of the swirl flow forming body 18 in the X1 axis direction is restricted. Thereafter, when the fluid coupling is assembled to the liquid supply unit 17, a fluid coupling component (for example, a buckling) is brought into contact with the other end of the outer peripheral portion 181. That is, the swirl flow forming body 18 is sandwiched between the stepped portion 21 and the liquid supply portion 17, and the position in the X1-axis direction is fixed.

  A pair of protrusions 184 and 185 extending along the circumferential direction are provided on the outer peripheral surface of the outer peripheral portion 181. The outer diameters of the protrusions 184 and 185 are set substantially equal to the inner diameter of the swirl flow forming body accommodation space 19. That is, an annular space 22 sandwiched between the protrusions 184 and 185 is formed between the outer peripheral portion 181 and the inner peripheral surface of the swirl flow forming body accommodation space 19. Further, outside the protrusions 184 and 185 (outside the annular space 22), O-rings 25 and 26 are arranged in close contact with the respective protrusions, so that the annular space 22 is maintained airtight. In order to prevent displacement of the O-rings 25 and 26, the outer peripheral surface at the position where the O-ring is disposed may be formed in a groove shape.

  The lateral hole 13 is formed at a position corresponding to the annular space 22, and the annular space 22 constitutes a gas passage together with the lateral hole 13. The horizontal hole 13 is provided with a flow rate adjusting mechanism 23 using, for example, a needle screw 27 in order to control the flow rate of the supplied gas. Moreover, in this embodiment, the gas supply part 24 is provided in the hole 14 along the X2 axis. The gas supply unit 24 is also provided with a fluid coupling such as a push-in coupling, for example, and a flexible tube (not shown) is connected to supply gas to the fine bubble generating device 10. That is, gas can be supplied to the annular space 22 through the hole 14 and the horizontal hole 13, and the flow area is controlled by adjusting the position of the needle screw to adjust the gas flow rate.

  The swirl flow forming body 18 is provided with a gas passage that communicates from the outer peripheral surface between the protrusions 184 and 185 to the center of the top surface of the trapezoidal portion 183 as will be described in detail later. That is, the gas-liquid mixing space 16 communicates with the annular space 22 through a gas passage provided in the center of the top surface of the trapezoidal portion 183, and the annular space 22 is connected to the gas supply portion 24 through the lateral hole 13 and the hole 14. Communicated to

  Next, a more detailed structure of the swirl flow forming body 18 of the present embodiment will be described with reference to FIGS. FIG. 2 is a plan view of the swirl flow forming body 18, and FIG. 3 is a plan view from the III direction of FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3, and FIGS. 5 and 6 are arrow views of the main body 180 from the V direction and the VI direction in FIG. 5 and 6, the outer peripheral portion 181 is shown in a sectional view.

  As shown in FIGS. 3 to 6, a plurality of spiral slopes are provided between the cylindrical portion 182 and the outer peripheral portion 181 of the swirling flow forming body 18, and the cylindrical portion 182 and the outer peripheral portion 181 are connected by the spiral slope. The In this embodiment, a pair of spiral slopes 186 and 187 are provided, and the spiral slopes 186 and 187 are provided at an inclination angle of 5 ° to 45 °, for example, approximately 180 ° around the cylindrical portion 182. The high-pressure liquid supplied from the liquid supply unit 17 passes through the inside of the outer peripheral portion 181, reaches the spiral slopes 186 and 187, and is ejected along the spiral slopes 186 and 187 into the frustoconical space 20. The start ends (upstream sides) 186A and 187A of the spiral slopes 186 and 187 are raised substantially in the axial direction.

  In the present embodiment, the gas passage is communicated from the main body 180 to the outer peripheral portion 181 side using at least one starting end portion of the plurality of spiral slopes. For example, in the present embodiment, the starting end portion 186A is formed as a thick portion, and a gas passage is formed therein. As shown in FIGS. 3 to 5, the gas passage includes, for example, a first gas passage 188 along the central axis of the main body 180 (cylindrical portion 182 and trapezoidal portion 183) of the swirling flow forming body 18, and a thick portion (starting end). 186A) and the second gas passage 189 communicating with the first gas passage 188 to the outer peripheral surface of the outer peripheral portion 181.

  Further, beams 190 and 191 extending along the cylindrical axis direction from the respective start end portions 186A and 187A are formed on the inner peripheral surface of the outer peripheral portion 181. The beams 190 and 191 extend to a predetermined height along the inner peripheral surface of the outer peripheral portion 181, and the tip of the beams 190 abuts on the tip of a flexible tube (not shown) attached to the liquid supply portion 17 to position the tube. Do. Further, as shown in FIG. 3, a chamfered portion (192) is provided on a part of the outer peripheral surface of the outer peripheral portion 181, and positioning in the rotational direction when the swirling flow forming body 18 is mounted in the swirling flow forming body accommodation space 19. It can also be used.

  As described above, according to the present embodiment, since a high-pressure liquid can be supplied straight from the liquid supply unit to the swirling flow forming body, the pressure loss of the liquid can be reduced. Moreover, since the gas supply path and the liquid supply path can be branched at the position of the swirl flow forming body by supplying the gas from the side hole provided in the swirl flow forming body accommodating space, the configuration is extremely simplified and the number of parts is reduced. It can be greatly reduced.

  Further, when the swirl flow forming body is assembled into the fine bubble generator, the swirl flow forming body can be inserted from the liquid supply unit side, so that the swirl flow forming body is separated from the nozzle side with the nozzle tip as a separate body as in the prior art. There is no need to wear the structure, and the structure can be further simplified.

  Furthermore, in this embodiment, a pair of annular protrusions are provided on the outer periphery of the swirl flow forming body, and an opening of the gas passage (second gas passage) of the swirl flow forming body is provided between these protrusions. In order to maintain the airtightness of the space formed between the protrusions by placing the O-ring along both protrusions and press-contacting with the inner peripheral surface of the swirl flow forming body accommodating space, the airtightness is extremely simple. It becomes possible to maintain sex. In addition, the lateral hole that continues from the gas supply unit only needs to be provided at a position corresponding to the annular space formed between the projections, so that the processing tolerance is increased and swirl flow formation during assembly is achieved. Positioning in the rotational direction of the body is also facilitated.

  In this embodiment, since the spiral slope is a pair, the slope range is approximately 180 ° (actually narrow due to the thick portion and the beam). However, this does not overlap the spiral slope in the axial direction. When the number of spiral slopes is n, the spiral slope range may be narrower than 360 ° / n.

  Moreover, in this embodiment, the main body (cylindrical part, trapezoid part), spiral slope, thick part, beam, outer peripheral part, projection part, first gas passage, and second gas passage of the swirl flow forming body are formed by injection molding. It is formed integrally.

DESCRIPTION OF SYMBOLS 10 Fine bubble generating apparatus 11 Fine bubble generating apparatus main body 12 Hole 13 Side hole 14 Hole 15 Nozzle 16 Gas-liquid mixing space 17 Liquid supply part 18 Swirling flow formation body 19 Swirling flow formation body accommodation space 20 Frustum trapezoid space 21 Step part 22 Ring shape Space 23 Flow rate adjusting mechanism 25, 26 O-ring 180 Swirling flow forming body main body 181 Outer peripheral portion 182 Cylindrical portion 183 Trapezoidal portion 184, 185 Protruding portion 186, 187 Spiral slope 188 First gas passage 189 Second gas passage 190, 191 Beam

Claims (7)

The liquid pressurized through the spiral passage is supplied to the gas-liquid mixing space in the nozzle to generate a swirling flow, and gas is introduced into the gas-liquid mixing space by using the negative pressure generated by the swirling flow. A two-phase swirl flow is formed, and the gas-liquid two-phase swirl flow is ejected from the nozzle so as to shear the gas-liquid two-phase fluid and to be fitted in an accommodation space provided in a fine bubble generator that generates fine bubbles. A swirl flow forming body forming a spiral passage ,
A body having a cylindrical portion;
An outer peripheral portion having a cylindrical inner peripheral surface coaxial with the cylindrical portion;
A spiral slope formed between the body and the outer periphery;
A thick portion communicating between the cylindrical portion and the outer peripheral portion at the start end of the spiral slope;
A first gas passage formed along the central axis of the cylindrical portion;
A swirling flow forming body comprising: a second gas passage that communicates the first gas passage to the outside of the outer peripheral portion through the thick portion. The outer peripheral portion has a cylindrical outer peripheral surface, a pair of annular projections are formed along a circumferential direction of the outer peripheral surface, and an opening of the second gas passage is between the pair of annular projections The swirl flow forming body according to claim 1, wherein the swirl flow forming body is formed as follows. The swirl flow forming body according to claim 1, wherein a plurality of the spiral slopes are provided, and the plurality of spiral slopes do not overlap with each other in the central axis direction. Is beginning before Symbol helical slope up along the cylindrical axis of the outer peripheral portion, the beam portion that Mashimasu extends along the cylindrical axis from the starting end is formed in a cylindrical inner peripheral surface of the outer peripheral portion The swirl flow forming body according to claim 1.   A microbubble generator to which the swirling flow forming body according to claim 1 is mounted, wherein a lateral hole is provided in a swirling flow forming body receiving space into which the swirling flow forming body is inserted, and when the swirling flow forming body is mounted. The fine bubble generating device is characterized in that the lateral hole is connected to the second gas passage.   The outer peripheral portion of the swirl flow forming body has a cylindrical outer peripheral surface, a pair of annular projections are formed along the circumferential direction of the outer peripheral surface, and the opening of the second gas passage is the pair of circular The microbubble generator according to claim 5, wherein the microbubble generator is formed between the annular protrusions, and the lateral hole is disposed between the pair of annular protrusions.   The O-ring is disposed on the outer side of the annular space formed between the pair of annular projections, adjacent to the annular projection, respectively. Fine bubble generator.

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