EP3320982A1

EP3320982A1 - Nozzle cleaning method and nozzle cleaning structure for atomization apparatus

Info

Publication number: EP3320982A1
Application number: EP17200252.9A
Authority: EP
Inventors: Hiroki YOSHIURA; Kenichi Harashima; Yoichi TOKUMICHI
Original assignee: Sugino Machine Ltd
Current assignee: Sugino Machine Ltd
Priority date: 2016-11-15
Filing date: 2017-11-07
Publication date: 2018-05-16
Also published as: JP2018079417A; CN108067387A; JP6614554B2

Abstract

Backwashing is used for easily eliminating clogging of a nozzle member (9). In high-pressure jetting, an inflow piping is connected with a first channel opening (10) and an outflow piping is connected with a fourth channel opening (12) to draw in pressurized fluid through the first opening first (10) toward the fourth channel opening (12). In backwashing, the inflow piping is connected with the fourth channel opening (12) and the outflow piping is connected with the first channel opening (10) to draw in pressurized fluid through the fourth channel opening (12) to the first channel opening (10), so as to expel material particles that are to clog a channel of a nozzle member.

Description

BACKGROUND

1. Technical Field

The present disclosure relates to a nozzle cleaning method and a nozzle cleaning structure for eliminating clogging of a nozzle member in an atomization apparatus in which streams of highly pressurized fluid collide with each other. 2. Description of the Background
Atomization is a concept of pulverizing, dispersing, or emulsifying solid particles into fine particles. Atomization apparatuses have been known to cause jet streams containing target materials to collide with each other for atomization.
Japanese Patent Application Laid-Open No. 2005-144329 (hereinafter, referred to as "Patent Literature 1") and Japanese Patent No. 5021234 (hereinafter, referred to as "Patent Literature 2") each disclose a mechanism of atomization, in which a pressurized liquid mixture of a solvent and material particles is supplied through an introductory channel toward a plurality of acceleration channels of a nozzle member, and while flowing in the acceleration channels, the material particles are subjected to shearing force and are atomized by the energy that occurs when streams of the mixture collide each other. Fig. 10 shows a conventional atomization apparatus 200, illustrative of the apparatuses discussed in Patent Literatures 1 and 2, in which ultra-highly pressurized material is introduced into a housing 201 through an introductory channel opening 210 and an introductory channel 211 as a plurality of streams. When passing through a gap (or slit) between two diamonds (i.e., main constituent) of a nozzle member 209, namely, a fine acceleration channel 214, the streams are subjected to compression, shearing, and turbulence. At a collision part 226, the streams of the pressurized fluid counter-collide with each other to atomize the material particles. Then, the pressurized material particles are jetted into a through hole 217 and a jet-receiving member 222, to be discharged through a discharge channel 213 and a discharge channel opening 212. In the atomization apparatus 200 with a slit-type chamber in which the nozzle member 209 provides a slit, emulsification performance is especially improved. For emulsification of cosmetics, foods, medicines, or the like, the high collision energy and strong shearing force enhances the emulsification more than counter collision itself.

BRIEF SUMMARY

In recent years, there is a tendency of reducing the diameter of a fine acceleration channel (namely, the inner diameter of a fine acceleration channel) to reduce erosion at a jet stream collision part caused by increase in flow rate and to improve atomization such as emulsification and dispersion, for increase in the amount of production. However, the decreased diameter is easy to cause clogging (blockage) with material particles in the fine acceleration channel. Conventionally, when clogging occurs in the fine acceleration channel 214, a user disassembles the atomization apparatus 200 entirely to clean the nozzle member 209: a user removes a first sealing member 202, a retainer member 204, the jet-receiving member 222, and a second sealing member 205, successively. Then the user takes out the nozzle member 209 and cleans the interiors of the fine acceleration channel 214 and the through hole 217. If the cleaning is ineffective to eliminate the clogging, the user has to replace the clogged nozzle member 209 with a new one. Thus, an easy way to eliminate the clogging has been needed.
The present disclosure is to provide a nozzle cleaning method and a nozzle cleaning structure for an atomization apparatus that uses backwashing to easily eliminate clogging in a nozzle member.
A first aspect of the present disclosure provides a nozzle cleaning method, comprising:

in high-pressure jetting, connecting an inflow piping with a first channel opening, and connecting an outflow piping with a fourth channel opening to draw in pressurized fluid through the first channel opening toward the fourth channel opening, and
in backwashing, connecting the inflow piping with the fourth channel opening, and connecting the outflow piping with the first channel opening to draw in the pressurized fluid through the fourth channel opening toward the first channel opening, so as to expel material particles that are to clog a channel of a nozzle member.

A second aspect of the present disclosure provides a nozzle cleaning structure for an atomization apparatus that draws in pressurized fluid from an inflow piping and discharges the pressurized fluid from an outflow piping, the structure comprising:

a first channel opening connectable to the inflow piping and the outflow piping;
a fourth channel opening connectable to the inflow piping and the outflow piping; and
a nozzle member including a fine acceleration channel where streams of pressurized fluid collide with each other, wherein
in high-pressure jetting, the inflow piping is connected with the first channel opening and the outflow piping is connected with the fourth channel opening to draw in the pressurized fluid through the first channel opening toward the fourth channel opening, and
in backwashing, the inflow piping is connected with the fourth channel opening and the outflow piping is connected with the first channel opening to draw in the pressurized fluid through the fourth channel opening toward the first channel opening, so as to expel material particles that are to clog the fine acceleration channel.

According to the nozzle cleaning method and the nozzle cleaning structure for the atomization apparatus according to the present disclosure, backwashing is effective to achieve easy elimination of clogging in a nozzle member.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 illustrates a schematic structure for an atomization apparatus according to a first embodiment.
Fig. 2 illustrates a schematic structure for an atomization apparatus according to a second embodiment.
Figs. 3A, 3B, and 3C are perspective diagrams illustrating a nozzle retainer according to the second embodiment.
Fig. 4 illustrates a schematic structure for an atomization apparatus according to a third embodiment.
Figs. 5A, 5B, and 5C are perspective diagrams illustrating a nozzle retainer according to the third embodiment.
Fig. 6 illustrates a schematic structure for an atomization apparatus according to a fourth embodiment.
Fig. 7 is a perspective diagram illustrating a third sealing member according to the fourth embodiment.
Fig. 8 illustrates a schematic structure for an atomization apparatus according to a fifth embodiment.
Figs. 9A, 9B, and 9C are perspective diagrams partially illustrating a nozzle member according to the fifth embodiment.
Fig. 10 illustrates an exemplary structure of a conventional atomization apparatus.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described below.

First Embodiment

Fig. 1 is a structural drawing illustrating an atomization apparatus 100 according to a first embodiment. The atomization apparatus 100 according to the present embodiment mainly includes a housing 1, a first sealing member 2, a pressing member 4, a second sealing member 5, a nozzle retainer 8, and a nozzle member 9. The housing 1 is substantially cup-shaped and has a predetermined thickness. The first sealing member 2 is fitted in the housing 1 to define a chamber 3 in the housing 1. The pressing member 4, which can be inserted from the first sealing member 2 side, is positioned in the chamber 3 and supports the second sealing member 5 to locate it at the center of the chamber 3. The nozzle retainer 8 is in contact with an inner wall of a third sealing member 7 which is attachable to and detachable from a substantially cup-shaped bottom surface 6 of the housing 1. The nozzle member 9 is held between the second sealing member 5 and the nozzle retainer 8. Note that, in Fig. 1, the housing 1 is illustrated as a substantially cup-shape in an inverted state, and thereby the bottom surface 6 is positioned on the upper side of Fig. 1.
The housing 1 includes a first channel opening 10 at one end. Through the first channel opening 10, pressurized fluid to be atomized is drawn in or discharged from the chamber 3. The housing 1 includes a first channel 11 that makes the first channel opening 10 communicated with the chamber 3. The first channel 11 extends through the housing 1. The pressurized fluid can be drawn into the first channel opening 10 and flows through the first channel 11 into the chamber 3, and alternatively can be discharged through the first channel opening 10 from the chamber 3.
Further, the housing 1 includes a fourth channel opening 12 at the other end. Through the fourth channel opening 12, pressurized fluid can be discharged from or drawn into the chamber 3. The housing 1 includes a fourth channel 13 that makes the fourth channel opening 12 communicated with the chamber 3. The fourth channel 13 extends through the housing 1. The pressurized fluid can be discharged from the chamber 3 through the fourth channel 13 and the fourth channel opening 12. Alternatively, pressurized fluid can be drawn into the chamber 3 through the fourth channel opening 12.
In the housing 1, the second sealing member 5 and the nozzle retainer 8 cooperatively support the nozzle member 9 to prevent the nozzle member 9 from coming into contact with an inner wall of the chamber 3. This structure creates a gap 15 between the inner wall of the chamber 3 and the nozzle member 9. By way of the gap 15, the first channel 11 is in communication with a fine acceleration channel 14 in the nozzle member 9. Hereinafter, the gap 15 is referred to as "second channel 15." In the housing 1, there is further a gap 16 between the pressing member 4 and the second sealing member 5. By way of the gap 16, a through hole 17 of the nozzle member 9 is in communication with the fourth channel 13. Hereinafter, the gap 16 is referred to as "third channel 16." Note that the material of the housing 1 is not particularly limited, and the examples include those used for the housings of existing atomization apparatuses.
The first sealing member 2 has a tapered shape along an inner wall of a first aperture 18 of the housing 1, and is in contact with the aperture 18 for sealing. The material of the first sealing member 2 is not particularly limited, but is preferably identical to that of the housing 1. The chamber 3 is a slit chamber in which the nozzle member 9 is located. The nozzle member 9 has a plurality of acceleration channels to atomize material particles by compression, shearing, turbulence, or the like that are caused when ultra-highly pressurized material-containing fluid passes through a gap (slit) between diamonds opposing with each other. The chamber 3 is a bottle-shaped cavity, and includes: a small-diameter cylindrical space on the bottom surface 6 side of the housing 1; a large-diameter cylindrical space on the first sealing member 2 side; and a tapered space that is located between the large-diameter and small-diameter spaces and that has a diameter gradually decreasing in the direction from the large-diameter cylindrical space to the small-diameter cylindrical space. The large-diameter cylindrical space accommodates the pressing member 4. The small-diameter cylindrical space accommodates a part of the nozzle member 9. The tapered space accommodates the remaining part of the nozzle member 9 and the second sealing member 5. The pressing member 4 presses the second sealing member 5 to keep a part of the second sealing member 5 in contact with an inner wall of the tapered space.
The pressing member 4 has a concave or cup-shaped structure. The pressing member 4 has two ends 19 that support the second sealing member 5 without closing an opening 20 of the through hole 17. The pressing member 4 has a jet-receiving member 22 fitted therein. The jet-receiving member 22 includes a hemispherical recessed wall surface 21 against which a jet stream of pressurized fluid collides. A passage hole 23 is located on one of the ends 19. By way of the passage hole 23, the third channel 16 is in communication with the fourth channel 13 to enable pressurized fluid to flow in and out therethrough. The pressing member 4 can be inserted and fitted into the chamber 3 through the first aperture 18, and kept in contact with an inner wall surface 1a of the housing 1 to firmly fix the second sealing member 5.
The second sealing member 5 has a concavity 24 centrally located, into which a tapered protrusion 9b of the nozzle member 9 is fitted. The fitting of the concavity 24 with the tapered protrusion 9b and the fixing of the second sealing member 5 by the pressing member 4 ensure the fixing of the nozzle member 9 in the chamber 3, while pressurized fluid flows in a forward direction. Note that the nozzle member 9 and the second sealing member 5 are in an integrally caulked state.
The bottom surface 6 has a second aperture 25 that is circular. The inner diameter of the second aperture 25 is not particularly limited, but can be equal to or less than the outer diameter of the cylindrical nozzle member 9 to enable pressurized fluid to flow in and out therethrough without blocking of the first channel 11 and the second channel 15 by the nozzle retainer 8. The third sealing member 7 has a part to be located and fitted inside of the housing 1 and is fixed to the housing 1 by fixing means such as screw and bolt. The part of the third sealing member 7 seals the second aperture 25 without any gap, thereby preventing pressurized fluid from leaking out of the atomization apparatus 100. The third sealing member 7 also supports the nozzle retainer 8 without any gap therebetween, preventing pressurized fluid from entering between the third sealing member 7 and the nozzle retainer 8. The size of the nozzle retainer 8 and the sealing pressure of the fixing means on the housing 1 are adjustable to control the pressing force of the nozzle retainer 8 acting on the nozzle member 9. Note that the third sealing member 7 and the nozzle retainer 8 can be integrated as a lid member which acts on the nozzle member 9 with its adjustable pressing force in backwashing. Here, the backwashing is an operation to eliminate clogging with impurities in the nozzle member 9, by flowing pressurized fluid in an opposite direction with respect to the flow direction of pressurized fluid in a normal high-pressure jetting, removing the impurities, and cleaning the interior of the nozzle.
The nozzle retainer 8 is supported by the inner part of the third sealing member 7 and the entire periphery of the second aperture 25. In the backwashing, the nozzle retainer 8 presses a cylindrical part 9a of the nozzle member 9 from the upper side thereof, that is, from the third sealing member 7 side, in order to prevent removal of the nozzle member 9 from the second sealing member 5. The nozzle retainer 8 is made of resin, preferably a material that is resistant to wear, such as wear-resistant engineering plastics (PEEK). The nozzle retainer 8 seals the inner part of the third sealing member 7 and the entire periphery of the second aperture 25 without gap therebetween respectively to prevent leakage of pressurized fluid. The second aperture 25 is located in the direction of the central axis of the nozzle member 9 on the cylindrical part 9a side in the housing 1, which allows the nozzle retainer 8 to easily press the cylindrical part 9a, and facilitates replacement of the nozzle retainer 8 with a new one.
The nozzle member 9 has the tapered protrusion at one end of its cylindrical body. The outer diameter of the nozzle member 9 is less than the inner diameter of the chamber 3. The nozzle member 9 is located centrally in the chamber 3 so as to face a part of the wall surface of the housing 1 with a gap created therebetween. The nozzle member 9 includes the fine acceleration channel 14 and the through hole 17. The fine acceleration channel 14 runs through the nozzle member 9 in a direction orthogonal to the central axis of the nozzle member 9. The through hole 17 extends from a central part 26 of the fine acceleration channel 14 in the direction of the central axis of the nozzle member 9. Insides of the fine acceleration channel 14 and the through hole 17, streams of fluid that contain material particles collide with each other to atomize the particles. The central part 26 can be also referred to as "collision part 26" where streams of the pressurized fluid collide with each other. The through hole 17 is a linear fluid passage orthogonal to the fine acceleration channel 14 and extending from an opening near the collision part 26 to the opening 20. By way of the through hole 17, the fine acceleration channel 14 is communicated with the third channel 16.
The nozzle member 9 can be composed of two nozzle members that are in press contact with each other and having a thin gap through their contact as the fine acceleration channel 14. However, preferably the nozzle member 9 is a single nozzle member including the fine acceleration channel 14 and the through hole 17. This is because the single nozzle member 9 including the fine acceleration channel 14 and the through hole 17 will not be separated or disassembled under the pressure load that is caused in backwashing in the direction opposite to the forward flow, and is excellent in durability.
The wall surface of the fine acceleration channel 14 is easy to wear due to shearing force of highly pressurized fluid. Particularly the wall surface of the central part 26 easily wears because streams of highly pressurized fluid collide with each other at the central part 26, and also in the backwashing, the pressurized fluid reversely flowing through the opening 20 collides against the wall surface. Accordingly, preferably the wall surface at the central part 26 is made of diamond. More preferably, the wall surfaces of the fine acceleration channel 14 near the collision part 26, the opening of the fine acceleration channel 14, and the through hole 17 are made of diamond. Alternatively, the entire wall surfaces of the fine acceleration channel 14 and the through hole 17 can be made of diamond to prolong the life of the nozzle member 9.
The first channel opening 10 is connectable with an inflow piping to draw in pressurized fluid from the outside of the atomization apparatus 100, and is connectable with an outflow piping to discharge pressurized fluid to the outside. Similarly, the fourth channel opening 12 is connectable with the inflow piping and with the outflow piping. This structure enables easy switching between the normal high-pressure jetting and the backwashing. The first channel opening 10 has an inner diameter greater than that of the first channel 11. The second channel 15 has an inner diameter greater than that of the fine acceleration channel 14. Note that the inner diameter of the first channel 11 can be equal to or greater than that of the second channel 15. Due to this dimensional relationship, in the backwashing, pressurized fluid clogging the fine acceleration channel 14 can be easily forced out of the nozzle member 9 to eliminate of the clogging. The fine acceleration channel 14 has an inner diameter less than that of the through hole 17. The through hole 17 has an inner diameter less than that of the third channel 16. The third channel 16 has an inner diameter less than that of the fourth channel opening 12. The inner diameter of the third channel 16 can be equal to or less than that of the passage hole 23, and the inner diameter of the passage hole 23 can be equal to or less than that of the fourth channel 13. This dimensional relationship, in the backwashing, facilitates flow-in of pressurized fluid into the fine acceleration channel 14 from outside of atomization apparatus 100, and elimination of clogging. Further, it is preferable that cross sections of the first channel opening 10, the first channel 11, the fine acceleration channel 14, the through hole 17, the passage hole 23, the fourth channel 13, and the fourth channel opening 12 are substantially circular. In the backwashing, the circular shape enhances smooth flow of pressurized fluid therethrough, which facilitates elimination of clogging.
Next, operations of the atomization apparatus 100 according to the present embodiment will be described below. As the solid arrows indicate in Fig. 1, in the normal high-pressure jetting, an inflow piping is connected with the first channel opening 10 and an outflow piping is connected with the fourth channel opening 12. Then, a liquid mixture of a solvent and material particles is pressurized with a predetermined pressing means to obtain a pressurized fluid at approximately 100 MPa to 150 MPa, and the pressurized fluid is drawn into the first channel opening 10. The pressurized fluid flows through the second channel 15 located along the outer periphery of the nozzle member 9, and through the openings on a column-part side of the nozzle member 9, and enters the fine acceleration channel 14. Then, as the pressurized fluid flows in streams back-radially toward the center of the nozzle member 9, the streams of the pressurized fluid are subjected to shearing force, and collide with each other at the collision part 26, and thereby the material particles are atomized. That is, the material particles are atomized by the shearing force of the mixture passing through the fine acceleration channel 14 and by the collision energy of the mixture streams. Subsequently, the pressurized fluid enters the through hole 17 from the opening located near the collision part 26, and is discharged from the opening 20 of the through hole 17. Note that, in the normal high-pressure jetting, when the pressurized fluid having passed through the first channel 11 collides with the nozzle retainer 8, minute impurities can come into the pressurized fluid. However, removing the nozzle retainer 8 in advance will avoid the risk.
When clogging occurs in the fine acceleration channel 14 due to impurities of coarse or coagulated material particles, the backwashing is required. As the dashed arrows indicate in Fig. 1, in the backwashing, an inflow piping is connected with the fourth channel opening 12 and an outflow piping is connected with the first channel opening 10. Then, pressurized fluid that is a solvent or a liquid mixture at 100 MPa or less is introduced in by pressing means through the fourth channel opening 12. In this pressurized cleaning, after the third sealing member 7 is once removed, the nozzle retainer 8 is mounted in the atomization apparatus 100. Then, the third sealing member 7 is attached again to seal the assembled nozzle retainer 8 so as to press and fix the nozzle member 9. The structure makes the fitting of the nozzle member 9 with the second sealing member 5 durable against the pressurized backwashing at 50 MPa to 100 MPa in the direction opposite to that of the normal high-pressure jetting, and prevents separation between the nozzle member 9 and the second sealing member 5. Then, the solvent or the liquid mixture pressurized at 50 MPa to 100 MPa is introduced through the fourth channel 13 into the fine acceleration channel 14 in the opposite direction for eliminating of clogging. The pressurized fluid to be used in the backwashing can be a solvent alone. However, it is easier to use the same liquid mixture of a solvent and material particles in the backwashing as that used in the normal high-pressure jetting. The temperature of the pressurized fluid used in the backwashing is not limited, but is preferably in a range from 40°C to 60°C for a material of higher viscosity. When the pressurized fluid is water, the temperature is preferably equal to or less than 70°C to prevent the temperature from exceeding the boiling point.
According to the present embodiment, only the attaching or detaching of the third sealing member 7 and the resin-made nozzle retainer 8 is required for the pressurized backwashing at 50 MPa to 100 MPa that achieves elimination of clogging, without disassembling of the entire atomization apparatus 100. In addition, the time required for the work to eliminate clogging according to the present embodiment is approximately two and a half minutes, whereas approximately 35 minutes was required conventionally: reduction in working time to approximately 1/14 can be achieved. Furthermore, events of failure in eliminating clogging can be reduced, leading to reduction in number of disposal of nozzle members.
Also, since the nozzle retainer 8 is made of a material resistant to wear in the pressurized cleaning at 100 MPa or less, the fitting between the nozzle member 9 and the second sealing member 5 and, in turn, the durable structure against the backwashing can be maintained.
In the present embodiment, the pressing member 4, the second sealing member 5, the nozzle retainer 8, and the nozzle member 9 have no sealing function, but the first sealing member 2 and the third sealing member 7 have the sealing function as separate members. In other words, the members having the piping connection function to connect with external inflow piping and the outflow piping are different from the members having the sealing function to seal the components such as the nozzle member 9 inside the housing 1. Therefore, the first channel opening 10 and the fourth channel opening 12 are located on surfaces or at positions of the housing 1 different from those of the first sealing member 2 and the third sealing member 7. In other words, the first channel 11 and the fourth channel 13 are not positioned in the first sealing member 2 and the third sealing member 7. For example, in the case where the housing 1 is cylindrical as in the present embodiment, the first sealing member 2 and the third sealing member 7 are located on a top surface or a bottom surface of the columnar body, while the first channel opening 10, the first channel 11, the fourth channel opening 12 and the fourth channel 13 are located on side surfaces of the columnar body. As a result, the apparatus structure can be simplified. Further, the pressing member 4 and the first sealing member 2 are located in the forward flow direction of pressurized fluid with respect to the through hole 17, for adequate pressing purpose of the nozzle member 9 and for sealing purpose respectively, during the normal pressurized jetting. In addition, for the purpose of appropriately pressing the nozzle member 9 in the backwashing, the nozzle retainer 8 and the third sealing member 7 are located in the backflow direction of pressurized fluid with respect to the through hole 17. Hence, the inflow/outflow directions of pressurized fluid in the first channel 11 and the fourth channel 13 (extending directions of the first channel 11 and the fourth channel 13) are different from the inflow/outflow directions of pressurized fluid in the through hole 17 (extending direction of the through hole 17). For example, in the present embodiment, the extending directions of the first channel 11 and the fourth channel 13 are orthogonal to the extending direction of the through hole 17 on the same plane.
The different members are responsible for the pipe connecting function and the sealing function in the present embodiment, but if a single member can be provided to be responsible for both the pipe connecting function and the sealing function, the single member is required to perform torque control for connecting external piping as well as torque control for sealing. In addition, the single member is responsible for sealing the openings to external piping as well as for sealing the housing 1 as a sealing member, and the sealings has to be reliably performed. In the present embodiment, at the time of switching from the normal pressurized jetting to the backwashing, the first channel opening 10 and the fourth channel opening 12 are once disconnected from external piping, and the connections to the external piping are switched. It is also necessary to detach the third sealing member 7 to detach the nozzle retainer 8. Accordingly, if a single member has both the pipe connecting function and the sealing function, the member needs to be set to perform two types of torque control and two types of sealing control at every backwashing, which increases workload of an operator. In the present embodiment, the pipe connecting function and the sealing function are performed by the different members: one member performs one torque control and one sealing control. As a result, easier work management and reduced workload can be achieved.

Second Embodiment

Fig. 2 is a structural drawing illustrating an atomization apparatus 100 according to a second embodiment. The atomization apparatus 100 according to the present embodiment includes a ring 27 around a nozzle retainer 8, and the nozzle retainer 8 remains attached to the atomization apparatus 100 during the normal high-pressure jetting. The atomization apparatus 100 according to the present embodiment includes structures similar to those described in the first embodiment and redundant description thereof will be avoided.
In the atomization apparatus 100 according to the present embodiment, the nozzle retainer 8 having the ring 27 is to contact with the third sealing member 7 at the top surface, or with the nozzle member 9 at the bottom surface. When the nozzle retainer 8 is not in contact at its top or bottom surface, the ring 27 come into contact with the third sealing member 7 or the nozzle member 9. The shape and position of the nozzle retainer 8 is not particularly limited as long as, in the backwashing, the nozzle retainer 8 is kept in contact with the nozzle member 9 and absorbs the impact force imparted to the collision part 26 by pressurized fluid. In the atomization apparatus 100, the ring 27 is located in a flow direction 28 of pressurized fluid the first channel 11 in the normal high-pressure jetting, that is, at a position 29 where pressurized fluid collides with the nozzle retainer 8 after flowing through the first channel 11.
Fig. 3 is a perspective diagrams illustrating the nozzle retainer 8 having the ring 27 according to the present embodiment, in which dotted lines indicate the internal structures. For example, the nozzle retainer 8 has a circular or square columnar body. The ring 27 has a hollow cylindrical body surrounding the nozzle retainer 8 (Figs. 3A and 3C). Alternatively, the ring 27 has a hollow square columnar body (not illustrated), or a substantially cup-shaped body (Fig. 3B). The nozzle retainer 8 and the ring 27 can be fixed together by means of adhesive means such as a chemical material. Alternatively, the ring 27 and the nozzle retainer 8 can be fixed to each other using their structural features: for example, the ring 27 can be fitted into a recess on a side surface of the nozzle retainer 8 (Figs. 3B and 3C). The material of the ring 27 is not particularly limited as long as it is corrosion-resistant, pressure-resistant, and wear-resistant enough to stand against the high-pressure jetting of pressurized fluid: for example, metal materials such as stainless steel, aluminum, and alloy are preferable, and elastic materials having super wear resistance can be used.
In the normal high-pressure jetting, the ring 27 absorbs the impact force imparted by the pressurized fluid when it collides with the nozzle retainer 8 after flowing through the first channel 11. Therefore, contamination of minute impurities into the pressurized fluid due to wear of the nozzle retainer 8 can be prevented. The ring 27 is not limited to have a ring shape as long as the ring 27 is located in the atomization apparatus 100 to prevent the pressurized fluid from directly colliding with the nozzle retainer 8. For example, the ring 27 can be a plate-like member. Further, the nozzle retainer 8 according to the present embodiment can be attached not only in the backwashing but also during the normal high-pressure jetting. Although the nozzle retainer 8 is attachable and detachable together with the third sealing member 7, detaching the nozzle retainer 8 is unnecessary even in the normal high-pressure jetting, because wear of the nozzle retainer 8 and generation of impurities from the nozzle retainer 8 can be prevented by the ring 27. As a result, the workability can be improved.

Third Embodiment

Fig. 4 is a structural drawing illustrating an atomization apparatus 100 according to a third embodiment. The atomization apparatus 100 according to the present embodiment includes two third sealing members 7. Each of the third sealing members 7 has a channel opening 31 and a channel 32 continuously connected to the channel opening 31. The nozzle retainer 8 includes a part 11b of the first channel 11 and a part 15a of the second channel 15 therein. The atomization apparatus 100 according to the present embodiment includes structures similar to those described in the first embodiment and redundant description thereof will be avoided.
Depending on the external piping to connect, one of the two third sealing members 7 serves as an introduction-side sealing member 33 and the other serves as a discharge-side sealing member 34. More specifically, the sealing member connected to the inflow piping is the introduction-side sealing member 33, through which pressurized fluid is drawn into the chamber 3 from the outside of the atomization apparatus 100. The sealing member connected to the outflow piping is the discharge-side sealing member 34, through which pressurized fluid is discharged from the chamber 3 to the outside of the atomization apparatus 100. In the normal jetting, the nozzle retainer 8 can be removed, and the introduction-side sealing member 33 is connected to the second aperture 25 while the discharge-side sealing member 34 is connected to a third aperture 35. In the backwashing, the nozzle retainer 8 is attached, and the introduction-side sealing member 33 is connected to the third aperture 35 while the discharge-side sealing member 34 is connected to the second aperture 25 and also in contact with the nozzle retainer 8 for sealing (Fig. 4). In the switching between the normal high-pressure jetting and the backwashing, the external piping is not detached from the introduction-side sealing member 33 and the discharge-side sealing member 34, but the introduction-side sealing member 33 and the discharge-side sealing member 34 are detached from the housing 1. The introduction-side sealing member 33 and the discharge-side sealing member 34 can be identical in shape. The shape is not specifically limited as long as the introduction-side sealing member 33 and the discharge-side sealing member 34 are alternately connectable to the second aperture 25 and the third aperture 35 to provide a channel therein that does not block the flow of pressurized fluid.
When the third sealing member 7 is connected to the second aperture 25, the channel opening 31 serves as the first channel opening 10 and the channel 32 serves as a part 11a of the first channel 11. The nozzle retainer 8 includes the remaining part 11b of the first channel 11 formed therein. The part 11a and part 11b of the first channel 11 are continuously connected to each other along a central axis 30 to define the first channel 11. The nozzle retainer 8 further includes the part 15a of the second channel 15 being orthogonal to the first channel 11 and leading to the second channel 15. The second channel 15 is a gap located between the housing 1 and the nozzle member 9. When the third sealing member 7 is connected to the third aperture 35, the channel opening 31 serves as the fourth channel opening 12 while the channel 32 serves as a part 13a of the fourth channel 13 that leads to the fourth channel 13.
Fig. 5 is a perspective diagram illustrating the nozzle retainer 8 according to present embodiment, in which dotted lines indicate the internal structures. In the nozzle retainer 8, preferably the part 11b of the first channel and the part 11a of the first channel are identical in cross-sectional shape. The shape can be a cuboid or a polygonal prism, but a cylindrical, semi-cylindrical, or tunnel shape can make clogging hardly occur in the channels. Similarly, it is preferable that the part 15a of the second channel 15 located on an abutting side 36 to be in contact with the nozzle member 9, and the remaining part of the second channel 15 are identical in cross-sectional shape.
Similar to the first embodiment, the third sealing members 7 according to the present embodiment not only function as a sealing member covering the nozzle retainer 8 but also function as the first channel opening 10 and the fourth channel opening 12. In the backwashing, the external piping is not detached from the third sealing members 7, and a user detaches the third sealing members 7 from the housing 1 while maintaining the connection between the third sealing members 7 and the external piping, to switch between the normal high-pressure jetting and the backwashing. Since only detaching of two third sealing members 7 is required for the switching, the work for torque control is needed only for two portions, simplifying the work. Note that the fourth channel opening 12 resides in the third sealing member 7 to be attachable or detachable, but the structure described in the first embodiment can be employed alternatively. In this case, it is necessary to attach and detach the external piping.

Fourth Embodiment

Fig. 6 is a structural drawing illustrating an atomization apparatus 100 according to a fourth embodiment. Fig. 7 is a perspective diagram illustrating a third sealing member 7 according to the present embodiment in which dotted lines indicate the internal structure. The atomization apparatus 100 of the present embodiment includes the fourth channel opening 12 in the first sealing member 2, and the first channel opening 10 in the third sealing member 7. A nozzle retainer 8 is identical to that described in the first embodiment or the second embodiment. The atomization apparatus 100 includes structures similar to those described in the first embodiment, and redundant description thereof will be avoided.
The first sealing member 2 includes the fourth channel opening 12 and a part of the fourth channel 13. Further, the pressing member 4 and the jet-receiving member 22 includes the remaining part of the fourth channel 13. The first sealing member 2, the pressing member 4, and the jet-receiving member 22 are serially arranged to cooperatively define the fourth channel 13 that linearly extends therethrough. The third sealing member 7 includes the first channel opening 10 and part of a first channel 11. The first channel 11 includes a large-diameter cylindrical channel 11a and a plurality of small-diameter cylindrical channels 11b, and leads to a second channel 15 (Fig. 6 and Fig. 7).
Unlike the third embodiment, the nozzle retainer 8 according to the present embodiment has no channel. Further, as the first channel 11 and the second channel 15 are linearly connected, pressurized fluid can flow along a side of the nozzle retainer 8 without colliding with the nozzle retainer 8. As a result, the wear of the nozzle retainer 8 can be suppressed. Further, in a case where the nozzle retainer 8 has the ring 27 described in the second embodiment, the wear of the nozzle retainer 8 can be further prevented. Therefore, the normal jetting can be performed with the nozzle retainer 8 attached. As there is no necessity of detaching the nozzle retainer 8, the work is simplified.

Fifth Embodiment

Fig. 8 is a structural drawing illustrating an atomization apparatus 100 according to a fifth embodiment. In the atomization apparatus 100 according to the present embodiment, a cylindrical part 9a of a nozzle member 9 is in contact with the housing 1 to fix the nozzle member 9 in the chamber 3. A second channel 15a is included in the cylindrical part 9a that is in contact with the housing 1, and thereby pressurized fluid can flow in the chamber 3 through the second channel 15a. The atomization apparatus 100 does not require the nozzle retainer 8 and the third sealing member 7 described above. A first channel opening 10 and a first channel 11 are disposed along a central axis 30, and in the chamber 3, an opening of the first channel 11 is in contact with a central region of the cylindrical part 9a. The atomization apparatus 100 according to the present embodiment includes structures similar to those described in the first embodiment and redundant description thereof will be avoided.
Fig. 9 is a perspective diagram illustrating the cylindrical part 9a according to the present embodiment, in which dotted lines indicate the internal structures. Apart 15a of the second channel located at an end 9c of the cylindrical part 9a can have a cuboid shape (Fig. 9A), a columnar shape (Fig. 9B), or a combination thereof (Figs. 9B and 9C). Although the shape is not specifically limited, preferably the part 15a has an appropriate shape that does not disturb the flow of pressurized fluid and that is unlikely to cause clogging. The atomization apparatus 100 according to the present embodiment does not require the nozzle retainer 8, eliminating attaching and detaching of the nozzle retainer 8.
Although various embodiments have been described, the present disclosure is not limited to only the illustrated embodiments. The above-described embodiments can be combined appropriately for use, and it is needless to say that the present disclosure can be appropriately changed within the scope not departing from the gist thereof.

Reference Signs List

100: atomization apparatus
1: housing
1a: inner wall surface of housing
2: first sealing member
3: chamber
4: pressing member
5: second sealing member
6: bottom surface
7: third sealing member
8: nozzle retainer
9: nozzle member
9a: cylindrical part
9b: tapered protrusion
9c: end
10: first channel opening
11, 11a, 11b: first channel
12: fourth channel opening
13: fourth channel
14: fine acceleration channel
15, 15a: second channel (gap)
16: third channel (gap)
17: through hole
18: first aperture
19: both ends
20: opening of through hole
21: recessed wall surface
22: jet-receiving member
23: passage hole
24: concavity
25: second aperture
26: collision part (central part)
27: ring
28: flow direction
29: collision position
30: central axis
31: channel opening
32: channel
33: introduction-side sealing member
34: discharge-side sealing member
35: third aperture
36: abutting side
37: bottom part of third sealing member

Claims

A nozzle cleaning method, comprising:
in high-pressure jetting, connecting an inflow piping with a first channel opening (10), and connecting an outflow piping with a fourth channel opening (12) to draw in pressurized fluid through the first channel opening (10) toward the fourth channel opening (12), and

in backwashing, connecting the inflow piping with the fourth channel opening (12), and connecting the outflow piping with the first channel opening (10) to draw in the pressurized fluid through the fourth channel opening (12) toward the first channel opening (10), so as to expel material particles that are to clog a channel of a nozzle member (9).
The nozzle cleaning method according to claim 1, further comprising:
pressing the nozzle member (9) by a nozzle retainer (8) to prevent the nozzle member (9) from being separated from a second sealing member (5) that seals the nozzle member (9).
The nozzle cleaning method according to claim 1 or claim 2, further comprising,
in backwashing, drawing in pressurized fluid from the inflow piping through the fourth channel opening (12), the pressurized fluid being a solvent or a liquid mixture at 100 MPa or less.
A nozzle cleaning structure of an atomization apparatus that draws in pressurized fluid from an inflow piping and discharges the pressurized fluid from an outflow piping, the structure comprising:
a first channel opening (10) connectable to the inflow piping and the outflow piping;

a fourth channel opening (12) connectable to the inflow piping and the outflow piping; and

a nozzle member (9) including a fine acceleration channel (14) where streams of pressurized fluid collide with each other, wherein

in high-pressure jetting, the inflow piping is connected with the first channel opening (10) and the outflow piping is connected with the fourth channel opening (12) to draw in the pressurized fluid through the first channel opening (10) toward the fourth channel opening (12), and

in backwashing, the inflow piping is connected with the fourth channel opening (12) and the outflow piping is connected with the first channel opening (10) to draw in the pressurized fluid through the fourth channel opening (12) toward the first channel opening (10), so as to expel material particles that are to clog the fine acceleration channel (14).
The nozzle cleaning structure according to claim 4, further comprising:
a second sealing member (5) configured to seal the nozzle member (9), and

a nozzle retainer (8) configured to press the nozzle member (9), the nozzle retainer (8) configured to maintain fitting between the nozzle member (9) and the second sealing member (5) by absorbing collision force that is generated when the pressurized fluid collides with a wall surface of the fine acceleration channel (14) in backwashing.
The nozzle cleaning structure according to claim 5, further comprising:
a third sealing member (7) being in contact with the nozzle retainer (8), the third sealing member (7) configured to make the nozzle retainer (8) attachable or detachable, the third sealing member (7) configured to absorb the collision force to maintain the fitting between the nozzle member (9) and the second sealing member (5), the third sealing member (7) configured to control pressing force of the nozzle retainer (8) that presses the nozzle member (9).
The nozzle cleaning structure according to claim 6, further comprising:
a columnar housing (1) including the first channel opening (10) and the fourth channel opening (12) on side surfaces of the housing (1), the columnar housing (1) defining a channel (15) between a side of the nozzle retainer (8) and the columnar housing (1);

wherein the nozzle retainer (8) is located on the upstream side of the pressurized fluid in high-pressure jetting.
The nozzle cleaning structure according to any one of claims 5 to 7, further comprising:
a ring (27) located around the nozzle retainer (8) to prevent pressurized fluid from colliding with the nozzle retainer (8).
The nozzle cleaning structure according to claim 6, further comprising:
a cylindrical housing (1);

wherein the third sealing member (7) is located along a central axis of the nozzle retainer (8), and

the first channel opening (10) and first channels (11a, 11b) are located along a central axis of the third sealing member (7).
The nozzle cleaning structure according to any one of claims 4 to 9, wherein
the nozzle member (9) includes a through hole (17) having an inner diameter greater than an inner diameter of the fine acceleration channel (14), and
the first and fourth channel openings (10, 12) each have an inner diameter greater than the inner diameter of the through hole.