WO2021074966A1 - Spray head, spray nozzle, and spray device - Google Patents

Abstract

This spray head is provided with a coaxial tube, wherein: the coaxial tube is provided with an innermost tube, one or a plurality of intermediate tubes, an outermost tube, and a plurality of flow passages provided inside the innermost tube and between the tubes that are adjacent to one another in the inner-outer direction; the plurality of flow passages include an outside flow passage positioned on the outermost side, and a plurality of inside flow passages positioned inward of the outside flow passage; the outside flow passage is configured such that an assisting gas flows therethrough; each of the plurality of inside flow passages is configured such that a fluid other than the assisting gas flows therethrough; and a distal end portion of the outermost tube projects further in the axial direction of the coaxial tube than a distal end portion of the innermost tube and distal end portions of all the intermediate tubes.

Description

Spray head, spray nozzle, and spray device

The present disclosure relates to a spray head, a spray nozzle, and a spray device.

Patent Documents 1 and 2 disclose nozzles used for bioadhesives. The nozzle sprays two chemicals. The two chemicals discharged from the nozzle are mixed in the air from the discharge port of the nozzle until they adhere to the living body and adhere to the living body. By mixing and solidifying both chemicals, a coating film made of an adhesive is formed.

The nozzle described in Patent Document 1 includes two chemical supply pipes. Both chemical supply pipes are parallel pipes arranged so that the axes of the pipes are parallel to each other. Inside and outside each chemical supply pipe, an inner gas supply pipe and an outer gas supply pipe are arranged coaxially with each chemical supply pipe. The gas from each outer gas supply pipe sprays the chemical solution from each chemical solution supply pipe. The gas is called an assist gas.

The applicator described in Patent Document 2 includes three tubes coaxially. The inside of the innermost pipe is used for the flow path of the assist gas. The space between the innermost pipe and the adjacent intermediate pipe and the space between the intermediate pipe and the outermost pipe are used for the flow path of each component of the fibrin sealant. The tips of the three tubes are flush with each other and line up at the same axial position in the tubes.

Japanese Unexamined Patent Publication No. 2003-159255 Special Table 2000-515770

The spray head of the present disclosure is
A spray head with a coaxial tube
The coaxial tube
The innermost tube and
With one or more intermediate tubes,
The outermost tube and
A plurality of flow paths provided inside the innermost pipe and between adjacent pipes inside and outside the pipe are provided.
The plurality of flow paths
The outermost flow path located on the outermost side,
It is provided with a plurality of inner flow paths located inside the outer flow path.
The outer flow path is configured to allow the assist gas to flow.
Each of the plurality of inner flow paths is configured to allow a fluid other than the assist gas to flow.
The tip of the outermost pipe projects in the axial direction of the coaxial pipe from the tip of the innermost pipe and the tips of all the intermediate pipes.

The spray nozzle of the present disclosure is
With the spray head of the present disclosure
With a nozzle base connected to the spray head
The nozzle base includes a plurality of supply pipes and has a plurality of supply pipes.
Each of the plurality of supply pipes is connected between the innermost pipe and the one or a plurality of intermediate pipes and a plurality of tanks for storing each of the fluids in a separated state.

The spray device of the present disclosure is
With the spray head of the present disclosure or the spray nozzle of the present disclosure,
It is provided with a plurality of tanks for storing each of the fluids.

FIG. 1 is a perspective view showing a portion near a discharge port in the spray head according to the first embodiment. FIG. 2 is a cross-sectional view of the spray head shown in FIG. 1 cut along the II-II cutting line. FIG. 3A is a diagram illustrating a flow state of the assist gas in the spray head according to the first embodiment. FIG. 3B is a diagram illustrating a state in which a plurality of fluids are mixed in the spray head according to the first embodiment. FIG. 4 is a schematic configuration diagram showing a spray device according to the first embodiment. FIG. 5 is a cross-sectional view of the spray head according to the second embodiment in which a portion near the discharge port is cut by a plane parallel to the axial direction of the coaxial tube. FIG. 6 is a contour diagram of the flow velocity of the assist gas discharged from the nozzle of each sample in Test Example 1. FIG. 7A shows the sample No. 3 in Test Example 3. It is a schematic diagram which shows the state which the fluid discharged from the nozzle 1 is attached to an object. FIG. 7B shows the sample No. 3 in Test Example 3. It is a schematic diagram which shows the state which the fluid discharged from the nozzle of 102 is attached to an object.

[Issues to be solved by this disclosure]
When a plurality of fluids are adhered to an object in a mixed state to form a coating film of the mixture, it is desired that the plurality of fluids are uniformly mixed.

In the structure in which a plurality of fluids are mixed in the air between the discharge port of the nozzle and the object as in the nozzles described in Patent Documents 1 and 2, the plurality of fluids are not uniformly mixed. May adhere to the object.

In the nozzle provided with the parallel tube described above, it is difficult to uniformly mix a plurality of fluids as shown in a test example described later. Insufficient mixing can result in droplets of each fluid adhering to the object or a phase of each fluid in the coating. In particular, with this nozzle, it is difficult for a plurality of fluids to be mixed when the pressure of the assist gas is small. If the distance from the nozzle discharge port to the object is short and the pressure is small, it is more difficult for the plurality of fluids to be mixed. Hereinafter, the distance from the discharge port to the object may be referred to as a discharge distance.

When the above-mentioned discharge distance is short, the momentum of the assist gas tends to affect the formation of the coating film. Therefore, if the pressure of the assist gas is increased, a coating film having a non-uniform thickness, that is, a crater-like coating film is likely to be formed.

Therefore, one of the purposes of the present disclosure is to provide a spray head capable of uniformly mixing a plurality of fluids. Another object of the present disclosure is to provide a spray nozzle capable of uniformly mixing a plurality of fluids and a spray device.

[Effect of the present disclosure]
The spray head of the present disclosure, the spray nozzle of the present disclosure, and the spray device of the present disclosure can uniformly mix a plurality of fluids.

[Explanation of Embodiments of the present disclosure]
First, embodiments of the present disclosure will be listed and described.
(1) The spray head according to one aspect of the present disclosure is
A spray head with a coaxial tube
The coaxial tube
The innermost tube and
With one or more intermediate tubes,
The outermost tube and
A plurality of flow paths provided inside the innermost pipe and between adjacent pipes inside and outside the pipe are provided.
The plurality of flow paths
The outermost flow path located on the outermost side,
It is provided with a plurality of inner flow paths located inside the outer flow path.
The outer flow path is configured to allow the assist gas to flow.
Each of the plurality of inner flow paths is configured to allow a fluid other than the assist gas to flow.
The tip of the outermost pipe projects in the axial direction of the coaxial pipe from the tip of the innermost pipe and the tips of all the intermediate pipes.
The assist gas is a gas used for atomizing and discharging the fluid.

The spray head of the present disclosure can uniformly mix a plurality of fluids other than the assist gas as compared with the external mixing in which a plurality of fluids are mixed in the air from the discharge port to the object described above. In the spray head of the present disclosure, the tips of all the intermediate tubes and the innermost tubes are arranged to be retracted with respect to the tips of the outermost tubes. Therefore, in the outermost pipe, the space between the tip of the outermost pipe and the tip of the intermediate pipe and the innermost pipe can be used as a place for mixing the fluid. Since the flow path of the assist gas is not the inside of the innermost pipe but the outer flow path, a reflux vortex due to the assist gas is generated in the space. The reflux vortex mixes a plurality of fluids in the space. The details of the reflux vortex will be described later. Hereinafter, the space may be referred to as a mixing field.

Further, the spray head of the present disclosure can discharge the fluid mixed in the mixing field in the form of mist because the outermost pipe protrudes relatively.

By using the spray head of the present disclosure, a coating film composed of a mixture in which a plurality of fluids are uniformly mixed can be satisfactorily formed even when the pressure of the assist gas is small. Further, since the pressure of the assist gas may be small, a coating film having a uniform thickness is likely to be formed even when the discharge distance is short. The term "uniform" as used herein means not only that the material is strictly uniform, but also that the material includes a state that is determined to be substantially uniform according to the purpose.

(2) As an example of the spray head of the present disclosure,
Of the innermost pipe and the one or a plurality of intermediate pipes, the tips of two adjacent pipes are aligned at the same position in the axial direction, or of the two adjacent pipes located inside. The tip portion may be in the form of protruding in the axial direction from the tip portion of the pipe located on the outside.

The positions along the axial direction at the tip of each pipe arranged inside the outermost pipe may or may not be aligned. Therefore, there is a high degree of freedom regarding the arrangement of the above pipes.

(3) As an example of the spray head of (2) above,
The tip of the innermost pipe and the tips of all the intermediate pipes may be arranged at the same position in the axial direction.

In the above form, in the mixing field, a plurality of fluids other than the assist gas can be easily mixed uniformly without being hindered by all the pipes arranged inside the outermost pipe.

(4) The spray nozzle according to one aspect of the present disclosure is
With any one of the spray heads (1) to (3) above,
With a nozzle base connected to the spray head
The nozzle base includes a plurality of supply pipes.
Each of the plurality of supply pipes is connected between the innermost pipe and the one or a plurality of intermediate pipes and a plurality of tanks for storing each of the fluids in a separated state.

The spray nozzle of the present disclosure can uniformly mix a plurality of fluids. Therefore, when the spray nozzle of the present disclosure is used, a coating film composed of a mixture in which a plurality of fluids are uniformly mixed is satisfactorily formed. Further, since the pressure of the assist gas may be small as described above, a coating film having a uniform thickness is likely to be formed even when the discharge distance is short. In particular, the spray nozzles of the present disclosure do not include a junction in the nozzle base for mixing a plurality of fluids. The spray nozzle of the present disclosure mixes a plurality of fluids in the above-mentioned coaxial tube mixing field instead of the above-mentioned confluence. By using such a spray nozzle of the present disclosure, it is possible to prevent the coating film from containing the solidified material that may be formed at the confluence. Therefore, the coating film is formed better than the case where the merging portion is provided in the nozzle base.

(5) The spray device according to one aspect of the present disclosure is
With any one of the spray heads (1) to (3) above, or with the spray nozzle of (4) above.
It is provided with a plurality of tanks for storing each of the fluids.

The spray device of the present disclosure can uniformly mix a plurality of fluids. Therefore, the spray device of the present disclosure can satisfactorily form a coating film composed of a mixture in which a plurality of fluids are uniformly mixed. Further, since the pressure of the assist gas may be small as described above, the spray device of the present disclosure can easily form a coating film having a uniform thickness even when the discharge distance is short.

[Details of Embodiments of the present disclosure]
Hereinafter, embodiments of the present disclosure will be specifically described with reference to the drawings. In the figure, the same reference numerals mean the same names.

[Embodiment 1]
Hereinafter, the spray head of the first embodiment, the spray nozzle of the first embodiment, and the spray device of the first embodiment will be described with reference to FIGS. 1 to 4.
FIG. 2 is a cross-sectional view of the spray head 1 shown in FIG. 1 cut along a plane parallel to the axial direction of the coaxial tube 10.
FIG. 4 is a plan view of the spray device 6 of the first embodiment including the spray nozzle 5 of the first embodiment in a direction orthogonal to the axial direction of the coaxial tube 10. The main body 20 shown in FIG. 4 is partially cut out so that the inside can be seen.

(Overview)
The spray device 6 of the first embodiment shown in FIG. 4 is used to discharge a plurality of fluids 60, here two fluids 61 and 62, by an assist gas 64 discharged at a predetermined pressure. The plurality of fluids 60 are attached to an object (not shown) in a mixed state. A mixture of the plurality of fluids 60 constitutes a coating film on the surface of the object. The spray device 6 is configured so that the plurality of fluids 60 are mixed before being attached to the object. The spray head 1 of the first embodiment and the spray nozzle 5 of the first embodiment are used as parts constituting the discharge port 15 of the spray device 6.

The spray head 1 of the first embodiment includes a coaxial tube 10. The tip 140 of the outermost tube 14 located on the outermost side of the tubes constituting the coaxial tube 10 projects in the axial direction of the coaxial tube 10 from the tip of the other tubes (FIG. 2). The outer flow path 104 provided between the outermost pipe 14 and the pipe adjacent to the outermost pipe 14 is a flow path through which the assist gas 64 flows (FIG. 3B). Each of the plurality of inner flow paths 103 provided by the pipes located inside the outermost pipe 14 is a flow path through which the fluid 60 other than the assist gas 64 flows. When the spray head 1 provided with such a coaxial tube 10 is used, the plurality of fluids 60 are uniformly mixed as compared with the structure in which the plurality of fluids described above are discharged from the nozzle and then mixed in the air. To.
Hereinafter, the spray head 1, the spray nozzle 5, and the spray device 6 will be described in detail in this order.

(Spray head)
<Coaxial tube>
As shown in FIGS. 1 and 2, the coaxial tube 10 provided in the spray head 1 of the first embodiment includes an innermost tube 11, one or more intermediate tubes 12, an outermost tube 14, and a plurality of streams. It is provided with a road 100. The innermost pipe 11, the intermediate pipe 12, and the outermost pipe 14 are arranged in this order from the inside of the coaxial pipe 10, that is, the side closer to the axis of the coaxial pipe 10. These pipes constituting the coaxial pipe 10 are arranged coaxially with a predetermined interval between the pipes adjacent to each other inside and outside. The flow path 100 is provided inside the innermost pipe 11 and between the pipes adjacent to each other inside and outside the above. The plurality of flow paths 100 include an outer flow path 104 and a plurality of inner flow paths 103. The outer flow path 104 is located on the outermost side of the plurality of flow paths 100. Further, the outer flow path 104 is configured so that the assist gas 64 flows. The plurality of inner flow paths 103 are located inside the outer flow path 104. Each of the plurality of inner flow paths 103 is configured so that a fluid 60 other than the assist gas flows.

The coaxial tube 10 of this example is a triple tube including one innermost tube 11, one intermediate tube 12, and one outermost tube 14. In this example and the following description, the case where the intermediate pipe 12 is one is illustrated. In this example, the outer flow path 104 is provided between the outermost pipe 14 and the intermediate pipe 12. The inner flow path 103 includes a first flow path 101 and a second flow path 102. The first flow path 101 is provided inside the innermost pipe 11. The first flow path 101 is configured to allow the fluid 61 to flow. The second flow path 102 is provided between the innermost pipe 11 and the intermediate pipe 12. The second flow path 102 is configured to allow the fluid 62 to flow. In each tube, the cross-sectional shape cut by a plane orthogonal to the axial direction of the coaxial tube 10 is typically a cylindrical shape as in this example.

When the coaxial pipe 10 includes a plurality of intermediate pipes 12, the plurality of intermediate pipes 12 are arranged in parallel in the radial direction of the coaxial pipe 10 between the innermost pipe 11 and the outermost pipe 14. It is good to be provided. When the coaxial tube 10 includes a plurality of intermediate tubes 12, three or more fluids 60 can be mixed.

<Innermost pipe and intermediate pipe>
The innermost pipe 11 and the intermediate pipe 12 are cylinders that mainly form the inner flow path 103. The innermost pipe 11 includes an end portion on the side where the fluid 61 is introduced and a tip portion 110 which is an end portion on the side where the fluid 61 is discharged. The intermediate pipe 12 includes an end portion on the side where the fluid 62 is introduced and a tip portion 120 which is an end portion on the side where the fluid 62 is discharged. FIG. 1 shows the tip portion 110, the tip portion 120, and the tip portion 140, that is, the end faces on the discharge port 15 side with cross hatching.

<Outermost pipe>
The outermost pipe 14 is a cylinder that surrounds the innermost pipe 11 and the intermediate pipe 12. The outermost pipe 14 includes an end portion on the side where the assist gas 64 is introduced and a tip portion 140 which is an end portion on the side where the assist gas 64 is discharged.

<Arrangement of the tip of each pipe>
As shown in FIG. 2, among the tubes constituting the coaxial tube 10, the tips of all the tubes other than the outermost tube 14 and the tip 140 of the outermost tube 14 are displaced in the axial direction of the coaxial tube 10. There is. That is, the tip 110 of the innermost pipe 11, the tip 120 of the intermediate pipe 12, and the tip 140 of the outermost pipe 14 are not aligned. Specifically, the tip 140 of the outermost tube 14 protrudes from the tip 110 and the tip 120. In other words, both the tip portion 110 and the tip portion 120 are retracted from the tip portion 140 of the outermost tube 14 to the inside of the coaxial tube 10 and do not protrude from the tip portion 140. The lengths of the innermost pipe 11, the intermediate pipe 12, and the outermost pipe 14 and each other along the axial direction so that the tip portion 110, the tip portion 120, and the tip portion 140 have such an uneven arrangement. The position of is adjusted.

In this example, in the innermost pipe 11 and the intermediate pipe 12 which are two adjacent pipes, the tip portion 110 and the tip portion 120 are arranged at the same position in the axial direction of the coaxial pipe 10. That is, the end faces of the innermost pipe 11 and the intermediate pipe 12 on the discharge port 15 side are aligned on the same plane. The lengths of the innermost pipe 11 and the intermediate pipe 12 and their mutual positions along the axial direction are adjusted so that the tip portion 110 and the tip portion 120 have such a flat arrangement. In this form, in the mixing field 16 described later, a plurality of fluids 60 are easily mixed uniformly without being hindered by the innermost pipe 11 and the intermediate pipe 12.

<Mixing place>
The tip 110 of the innermost pipe 11 and the tip 120 of the intermediate pipe 12 are located inside the coaxial pipe 10 with respect to the tip 140 of the outermost pipe 14. Therefore, the coaxial tube 10 has a discharge port 15 formed by the tip portion 140 of the outermost tube 14. Further, the coaxial pipe 10 has a space inside the discharge port 15 surrounded by the tip 110 of the innermost pipe 11, the tip 120 of the intermediate pipe 12, and the inner peripheral surface 146 on the tip side of the outermost pipe 14. Have. Here, the space is referred to as a mixing field 16. The coaxial tube 10 uses the space in the vicinity of the discharge port 15 including immediately before the discharge port 15 as a place where a plurality of fluids 60 are mixed. So to speak, the coaxial tube 10 mainly performs internal mixing using the mixing field 16 instead of the above-mentioned external mixing.

The operation of the mixing field 16 will be described with reference to FIGS. 3A and 3B.
FIG. 3A shows the result of analyzing the flow state of the assist gas when only the assist gas is discharged from the coaxial tube 10 provided in the spray head 1 of the first embodiment by simulation.
FIG. 3B schematically shows the flow of the assist gas 64, the fluid 61, and the fluid 62 in the cross section of the spray head 1 of the first embodiment in which a portion near the discharge port 15 is cut in a plane parallel to the axial direction of the coaxial tube 10. Shown in.
In FIG. 3B, the solid arrow indicates the flow of the assist gas 64. The arrow of the alternate long and short dash line indicates the flow of the fluid 61 and the fluid 62. The dashed arrow indicates the flow of the mixture in which the fluid 61 and the fluid 62 are mixed.

The analysis was performed on the assumption that the assist gas 64 was discharged from the outer flow path 104 at a predetermined pressure using commercially available computational fluid dynamics (CFD) software. Here, only the mixing field 16 and the region in the vicinity thereof are analyzed. The analysis result is indicated by the direction of the arrow and the shade of the arrow. FIG. 3A shows the analysis result by adding a two-dot chain line indicating the innermost pipe 11, the intermediate pipe 12, and the outermost pipe 14, and a reference numeral. The injection direction of the assist gas is downward in FIG. 3A.

The direction of the arrow shown in FIG. 3A indicates the direction in which the assist gas flows. The difference in the shade of the arrow indicates the difference in the flow velocity of the assist gas. Here, by paying attention to the direction of the arrow, it can be understood that the assist gas flows in the direction of returning to the injection side in a swirling manner. The downward arrow group close to the inner peripheral surface of the outermost pipe 14, the left arrow group and the right arrow group in FIG. 3A, are assists discharged from between the outermost pipe 14 and the intermediate pipe 12 to the mixing field 16. It shows the flow of gas and the flow velocity is relatively high. The upward arrow group near the axis of the coaxial tube 10 and the central arrow group in FIG. 3A show the above-mentioned downwardly discharged assist gas swirling and returning upward, and the flow velocity is relatively slow.

When the assist gas 64 having a predetermined pressure is discharged from the outer flow path 104 to the mixing field 16, the assist gas 64 flows toward the discharge port 15 side along the inner peripheral surface 146 of the outermost pipe 14 and separates from the inner peripheral surface 146. , Flows toward the axial side of the coaxial tube 10 (see also FIG. 3B). The flow velocity of the assist gas 64 is relatively fast as it is closer to the inner peripheral surface 146, and is relatively slower as it is farther from the inner peripheral surface 146 and closer to the axis. Due to this difference in flow velocity, in the region around the axis of the coaxial tube 10, as shown by the upward arrow group in FIG. 3A, from the vicinity of the discharge port 15, the inside of the coaxial tube 10, that is, the innermost tube 11, the middle A flow of the assist gas 64 returning toward the pipe 12 side is generated. The assist gas 64 that has returned to the inside of the coaxial pipe 10 comes into contact with the tip 110 of the innermost pipe 11 and the tip 120 of the intermediate pipe 12, and spreads toward the inner peripheral surface 146 side and again to the discharge port 15 side. The flow is discharged together with the above-mentioned flow to the discharge port 15 side. It is considered that such a flow of the assist gas 64 near the mixing field 16 and the discharge port 15 is generated by using the outer flow path 104 as the flow path of the assist gas 64.

The assist gas 64 forms a reflux vortex, that is, a circulating flow, between the tip portion 110 and the tip portion 120 and the discharge port 15 and the region in the vicinity thereof as described above. In particular, the region in front of the tip 110 of the innermost pipe 11 and the tip 120 of the intermediate pipe in the discharge direction, that is, the region below the tip 110 and the tip 120 in FIG. 3A is the inner peripheral surface of the outermost pipe 14. Surrounded by 146. Therefore, the assist gas 64 temporarily stays in the mixing field 16 and does not spread. In addition, in the region in front of the tip 140 of the outermost pipe 14 in the discharge direction, that is, in the region below the tip 140 in FIG. 3A, the assist gas 64 discharged from the outer flow path 104 is around the coaxial pipe 10. While drawing in the gas of, it is blown forward. At this time, a flow of the assist gas 64 toward the inner peripheral side of the outermost pipe 14 is generated. Due to this flow, the fluid 61 and the fluid 62 discharged from the inner flow path 103 to the mixing field 16 are unlikely to spread in front of the tip 140 of the outermost pipe 14 in the discharge direction, that is, outside the discharge port 15. As a result, the fluid 61 and the fluid 62 are surely mixed in the mixing field 16.

As shown in FIG. 3B, when the fluid 61 and the fluid 62 at predetermined pressures are discharged from the inner flow path 103 to the mixing field 16, they flow toward the discharge port 15. At least a part of the fluid 61 and the fluid 62 is mixed by receiving the reflux vortex of the assist gas 64 described above until it reaches the discharge port 15. A mixture of the fluid 61 and the fluid 62 is discharged in a direction away from the discharge port 15. Further, the mixture is subdivided by the reflux vortex, becomes a mist, and is discharged from the discharge port 15.

As described above, the mixing field 16 has functions such as forming a reflux vortex of the assist gas 64, mixing a plurality of fluids 60, and atomizing the mixture.

<Protruding length>
The protruding length h (FIG. 2) of the outermost tube 14 may be more than 0 mm. The protruding length h of the outermost pipe 14 is between the tip of the innermost pipe 11 and the intermediate pipe 12 that protrudes most in the axial direction of the coaxial pipe 10 and the tip 140 of the outermost pipe 14. Is the distance along the axial direction. That is, the protruding length h is the minimum value among the above-mentioned distance from the tip portion 110 to the tip portion 140 of the innermost pipe 11 and the above-mentioned distance from the tip portion 120 to the tip portion 140 of the intermediate pipe 12. In this example, the tip 110 and the tip 120 are arranged at the same position in the axial direction. That is, the distance from the tip 110 to the tip 140 is equal to the distance from the tip 120 to the tip 140. Therefore, the protrusion length h may be any of the above distances.

If the protruding length h exceeds 0 mm, the coaxial tube 10 can secure the mixing field 16. Therefore, as compared with the case where the mixing field 16 is not provided, a coating film formed by uniformly mixing the plurality of fluids 60 is likely to be formed on the surface of the object. When the protrusion length h is (inner diameter D × 0.1) mm or more, further (inner diameter D × 0.2) mm or more, and (inner diameter D × 0.5) mm or more with respect to the inner diameter D of the outermost pipe 14. If there is, the mixing field 16 tends to be wider. Therefore, the plurality of fluids 60 are more likely to be mixed more reliably.

The upper limit of the protrusion length h is not particularly limited according to the results of the simulations of the inventors. The inventors have confirmed that if the protrusion length h is more than 0 mm, the plurality of fluids 60 are appropriately mixed and atomized and discharged from the discharge port 15. For example, the protruding length h may be 10 times or more the inner diameter D of the outermost pipe 14. The protrusion length h may be selected according to the arrangement relationship between the spray head 1 and the object.

However, the protruding length h affects the total length of the spray head 1. The protrusion length h does not need to be excessively long from the viewpoint of preventing solidification of the fluid 60, ease of cleaning, and the like. From the above viewpoint, the protrusion length h preferably satisfies h ≦ (inner diameter D × 2), and more preferably h ≦ about inner diameter D. The protrusion length h may be (inner diameter D × 0.9) mm or less, and further may be (inner diameter D × 0.8) mm or less.

From the viewpoint of securing the mixing field 16, preventing the fluid 60 from solidifying, and facilitating cleaning, the protrusion length h is (inner diameter D × 0.1) mm or more (inner diameter D × 0.9) mm or less, and further (inner diameter D × 0.9) mm. The inner diameter may be D × 0.2) mm or more (inner diameter D × 0.8) mm or less. The combination of the lower limit and the upper limit of the protrusion length h is not limited to these, and any combination of the above-mentioned preferable lower limit and the preferable upper limit is possible.

When the plurality of fluids 60 are, for example, bioadhesives, the protrusion length h is, for example, 0.5 mm or more and 1.5 mm or less.

<Dimensions of each pipe>
The size of each tube constituting the coaxial tube 10, for example, the inner diameter, the outer diameter, the thickness, and the like can be appropriately selected according to the application of the spray head 1.

The intermediate pipe 12 has an inner diameter larger than the outer diameter of the innermost pipe 11. When the coaxial tube 10 includes a plurality of intermediate tubes 12, the tube located on the outer side of the intermediate tube 12 has an inner diameter larger than the outer diameter of the tube located on the inner side. The outermost pipe 14 has an inner diameter D larger than the outer diameter of the innermost pipe 11 and the outer diameter of the intermediate pipe 12. The inner diameter D of the outermost tube 14 is the maximum inner diameter of the coaxial tube 10.

The inner diameter D of the outermost pipe 14 depends on the application of the spray head 1, and is, for example, 10 mm or less. The coaxial tube 10 having an inner diameter D of 10 mm or less is easy to use when the plurality of fluids 60 are, for example, a bioadhesive, a paint, or the like. Depending on the above applications and the like, the inner diameter D may be 9 mm or less, further 8 mm or less, 5 mm or less, and 3 mm or less. The lower limit of the inner diameter D is, for example, 1 mm or more, and further 1.5 mm or more.

The inner diameters of the innermost pipe 11 and the intermediate pipe 12 may be appropriately selected within the range of less than the inner diameter D of the outermost pipe 14 so that the inner flow path 103 having a predetermined size can be formed. For example, the inner diameter of the innermost pipe 11 is 0.3 mm or more, further 0.5 mm or more, 0.8 mm or more, 1.0 mm or more.

The thickness of each tube constituting the coaxial tube 10 depends on the application of the spray head 1 and the like, but for example, 0.1 mm or more and 1.0 mm or less can be mentioned. The thinner the innermost pipe 11 and the intermediate pipe 12 are, for example, 0.8 mm or less and 0.5 mm or less, the easier it is for the plurality of fluids 60 to come into contact with each other in the mixing field 16. Therefore, a plurality of fluids 60 are likely to be mixed in the mixing field 16.

The thickness of each tube constituting the coaxial tube 10 may be the same. Alternatively, the coaxial tube 10 may include tubes of different thicknesses. Note that FIG. 2 illustrates a case where the inner diameter, outer diameter, and thickness of each of the tubes constituting the coaxial tube 10 are uniform in the axial direction of the coaxial tube 10, but it does not have to be uniform. Further, the magnitude relationship of the thickness of each pipe shown in FIG. 2 is an example.

<Other configurations>
The spray head 1 of this example includes an exodermis 19. The outer skin 19 covers the outer circumference of the coaxial tube 10. The outer skin 19 mechanically protects the coaxial tube 10. The exodermis 19 may be omitted.

<material>
The constituent material of the coaxial tube 10 can be appropriately selected depending on the application of the spray head 1 and the like. For example, when the plurality of fluids 60 are bioadhesives, the constituent materials include resins having excellent resistance to each component of the bioadhesives. Alternatively, for example, when a plurality of fluids 60 are paints, the constituent materials include metals having excellent resistance to paints. Examples of the metal include stainless steel and the like.

(spray nozzle)
<Overview>
As shown in FIG. 4, the spray nozzle 5 of the first embodiment includes the spray head 1 of the first embodiment and the nozzle base 2. The nozzle base 2 connects the coaxial tube 10 provided in the spray head 1 with the fluid supply unit 3 described later and the gas supply unit 4 described later. The fluid supply unit 3 is a supply source for a plurality of fluids 60, here, fluid 61 and fluid 62. The gas supply unit 4 is a supply source of the assist gas 64.

In particular, in the spray nozzle 5 of the first embodiment, the fluid 61 and the fluid 62 are not mixed between the fluid supply unit 3 and the innermost pipe 11 and the intermediate pipe 12, and the fluid 61 and the fluid 62 are independently maximized. Discharge from the inner pipe 11 and the intermediate pipe 12.

Specifically, the nozzle base 2 includes a plurality of supply pipes, here, a supply pipe 21 and a supply pipe 22. Each of the supply pipe 21 and the supply pipe 22 connects the innermost pipe 11 and the intermediate pipe 12 provided in the coaxial pipe 10 of the spray head 1 to the plurality of tanks 31 and 32. The fluid 61 and the fluid 62 are stored in the tank 31 and the tank 32, respectively. In particular, each of the supply pipe 21 and the supply pipe 22 connects the fluid 61 and the fluid 62 in a separated state between the innermost pipe 11 and the tank 31 and between the intermediate pipe 12 and the tank 32. That is, the nozzle base 2 connected to the spray head 1 does not have a confluence portion for mixing a plurality of fluids 60.

Here, when the nozzle base includes the above-mentioned confluence, for example, when the fluid 61 and the fluid 62 are mixed and solidified by a chemical reaction or the like, if the reaction rate is high, the fluid 61 and the fluid 62 will be together. A solidified product formed by being mixed may be formed at the confluence. It is considered that the coating film cannot be formed satisfactorily because the solidified product generated at the confluence is contained in the mixture. In addition, the solidified product may cause hindering the flow of the mixture between the confluence portion and the discharge port 15. It is conceivable that the solidified product does not sufficiently discharge the mixture, so that the coating film is not formed well. On the other hand, since the spray nozzle 5 does not have the merging portion, the coating film made of the mixture can be formed satisfactorily as compared with the case where the merging portion is provided.

In addition, typically, the nozzle base 2 includes a main body portion 20. A coaxial tube 10, a fluid supply unit 3, and a gas supply unit 4 are attached to the main body portion 20. Further, the supply pipe 21 and the supply pipe 22 are housed in the main body 20, and the assist gas 64 is introduced.

<Supply pipe>
The nozzle base 2 of this example includes two supply pipes 21 and 22. Although the inner diameter and outer diameter of the supply pipe 21 and the supply pipe 22 are different, the basic configuration is the same.

The supply pipe 21 is a cylinder through which the fluid 61 is circulated by connecting the tank 31 for storing the fluid 61 and the innermost pipe 11 provided in the coaxial pipe 10. The supply pipe 21 introduces the fluid 61 from the tank 31 into the innermost pipe 11 without going through the above-mentioned merging portion.

The supply pipe 22 is a cylinder through which the fluid 62 is circulated by connecting the tank 32 for storing the fluid 62 and the intermediate pipe 12 provided in the coaxial pipe 10. The supply pipe 22 introduces the fluid 62 from the tank 32 into the intermediate pipe 12 without going through the above-mentioned merging portion.

The supply pipe 21 and the supply pipe 22 of this example are bent. Specifically, the supply pipe 21 and the supply pipe 22 include the following straight points and inclined points. The straight line portion is a portion arranged substantially parallel to the axial direction of the coaxial tube 10. The inclined portion is a portion arranged so as to intersect the axis of the straight portion. The ends of the straight points are connected to the tank 31 or the tank 32, respectively. The ends of the inclined portions are connected to the innermost pipe 11 or the intermediate pipe 12, respectively.

<Arrangement of supply pipes>
In this example, the supply pipe 21 and the supply pipe 22 are arranged in the main body 20 so that the distance between the tank 31 and the tank 32 on the connection side is wider than the distance between the tank 31 and the connection side with the coaxial pipe 10. Specifically, the above-mentioned straight points are arranged so that the axial directions of the above-mentioned straight points are parallel to each other, and are arranged apart from each other in the direction orthogonal to the axial direction. FIG. 4 shows a state in which the straight portion of the supply pipe 21 is located on the left side of the axis of the coaxial pipe 10 and the straight portion of the supply pipe 22 is located on the right side of the axis of the coaxial pipe 10. At each of the above-mentioned inclined portions, the ends connected to the innermost pipe 11 and the intermediate pipe 12 are arranged close to each other so as to face the coaxial pipe 10.

Since the distance between the supply pipe 21 and the tank 31 and the tank 32 on the connection side is wide, the spray nozzle 5 can easily arrange the fluid supply unit 3 including the tank 31 and the tank 32 in the main body 20.

<Other configurations>
The spray nozzle 5 of this example is provided with a funnel-shaped intervening portion 23 on the connection side with the coaxial tube 10. The intervening portion 23 is provided at a connection point between the supply pipe 21, the supply pipe 22, the innermost pipe 11, and the intermediate pipe 12. The end portion of the intervening portion 23 on the small diameter side has an inner diameter and an outer diameter equal to the inner diameter and the outer diameter of the intermediate pipe 12, and is connected to the intermediate pipe 12. The large-diameter end of the intervening portion 23 has an inner diameter larger than the total outer diameter of the supply pipe 21 and the supply pipe 22, and the supply pipe 21 is inserted and the supply pipe 22 is connected. Specifically, the end portion on the large diameter side is sealed by the lid portion so that the assist gas 64 does not enter. The lid is provided with two through holes. The supply pipe 21 is inserted into the end portion on the large diameter side from one of the two through holes and is connected to the innermost pipe 11. The supply pipe 22 is connected to the peripheral edge of the through hole so as to communicate with the other through hole, and is fixed to the end portion of the large diameter portion. The spray nozzle 5 provided with such an intervening portion 23 can easily supply the fluid 61 and the fluid 62 having a predetermined capacity from the supply pipe 21 and the supply pipe 22 to the innermost pipe 11 and the intermediate pipe 12.

As shown in FIG. 4, the main body 20 of this example has a shape in which the region on the coaxial tube 10 side is tapered when viewed in a direction orthogonal to the alignment direction of the two supply pipes 21 and 22. In addition to accommodating the supply pipe 21 and the supply pipe 22, the main body 20 is provided with a through hole 40 for introducing the assist gas 64. The main body portion 20 of this example further includes a wall portion 24 that partitions an area in which the assist gas 64 is introduced in the internal space of the main body portion 20. The wall portion 24 is provided so as to surround the through hole 40 and be connected to the outermost pipe 14. The size of the through hole 40, the internal capacity of the wall portion 24, and the like may be adjusted so that the assist gas 64 introduced from the through hole 40 has a predetermined pressure. The shape, size, etc. of the main body 20 can be changed as appropriate.

(Spray device)
<Overview>
The spray device 6 of the first embodiment includes the spray head 1 of the first embodiment or the spray nozzle 5 of the first embodiment, and a plurality of tanks, here, a tank 31 and a tank 32.

In addition, typically, the spray device 6 is provided with a pressurizing mechanism (not shown) for discharging the tank 31, the fluid 61 in the tank 32, and the fluid 62 at a predetermined pressure. The fluid supply unit 3 includes this pressurizing mechanism, a tank 31, and a tank 32. Further, typically, the spray device 6 includes a gas supply unit 4 for discharging the assist gas 64 at a predetermined pressure. The fluid supply unit 3 and the gas supply unit 4 are fixed to the main body 20 of the spray nozzle 5.

<Fluid supply unit>
The fluid supply unit of this example includes the above-mentioned two tanks 31 and 32. A supply pipe 21 and a supply pipe 22 are connected to the tank 31 and the tank 32, respectively. The tank 31 and the tank 32 supply the tank 31, the fluid 61 in the tank 32, and the fluid 62 to the innermost pipe 11 and the intermediate pipe 12 via the supply pipe 21 and the supply pipe 22. The capacities of the tanks 31 and 32 can be appropriately selected.

As the pressurizing mechanism provided in the fluid supply unit 3, a pressurizing mechanism having an appropriate configuration capable of applying a predetermined pressure to each fluid 60 can be used depending on the application of the spray device 6 and the like. When the plurality of fluids 60 are, for example, bioadhesives, the pressurizing mechanism may include a syringe or the like. The syringe typically comprises a tubular barrel, a plunger rod, and a piston or gasket. The plunger rod is inserted into the barrel. The piston is attached to the tip of the plunger rod. FIG. 4 shows only a part of the barrel of the syringe. When two syringes are provided as illustrated in FIG. 4, the structure may be such that the rear end side of the two plunger rods, that is, the end portion opposite to the piston is connected. This structure can supply two fluids 61 and 62 at the same time.

<Gas supply unit>
The gas supply unit 4 includes a tank for storing the assist gas 64 and a pressurizing mechanism for discharging the assist gas 64 in the tank at a predetermined pressure. As the pressurizing mechanism, one having an appropriate configuration capable of applying a predetermined pressure to the assist gas 64 can be used. The details of the gas supply unit 4 are not shown.

For the basic configuration of the spray nozzle 5 and the basic configuration of the spray device 6, a known configuration may be referred to.

(Use)
The spray head 1, the spray nozzle 5, and the spray device 6 of the first embodiment typically discharge a plurality of fluids 60 other than the assist gas to form a coating film composed of a mixture of the plurality of fluids 60. Can be used for. The fluid 60 other than the assist gas 64 is typically a liquid. Specific examples of the liquid include various adhesives and paints. Of the plurality of fluids 60, at least one fluid 60 may be a gas other than the assist gas. Examples of the assist gas 64 include air and the like.

In particular, the spray head 1, the spray nozzle 5, and the spray device 6 can be suitably used when a plurality of fluids 60 are mixed and solidified. One of the reasons for this is that the plurality of fluids 60 are uniformly mixed by the mixing field 16 as described above. Another reason is that the outermost pipe 14 is relatively protruding as described above, so that the mixture of the plurality of fluids 60 is discharged in the form of mist.

Examples of the plurality of fluids 60 that solidify when mixed include a multi-component mixed type bioadhesive and a multi-component mixed type paint. Examples of the two-component mixed type bioadhesive include a fibrinogen-containing solution and a thrombin-containing solution. In this case, the assist gas 64 may be a sterile gas or the like.

(Main actions / effects)
The spray head 1, the spray nozzle 5, and the spray device 6 of the first embodiment can uniformly mix a plurality of fluids 60 as compared with the case where they are mixed in the air from the discharge port of the nozzle to the object. This effect will be specifically described with reference to the following test examples.

If the spray head 1, the spray nozzle 5, or the spray device 6 of the first embodiment is used, a coating film of a mixture in which a plurality of fluids 60 are mixed is satisfactorily formed. Since the pressure of the assist gas 64 may be small, a coating film having a uniform thickness is likely to be formed even when the discharge distance is short. Therefore, the spray head 1, the spray nozzle 5, or the spray device 6 can be suitably used when it is desired to reduce the pressure or the discharge distance.

Further, since the coaxial tube 10 constitutes the mixing field 16, for example, a member for mixing a plurality of fluids 60 is not required on the discharge port 15 side. The spray head 1, the spray nozzle 5, or the spray device 6 of the first embodiment has a simple structure and is excellent in manufacturability.

Further, in the spray nozzle 5 of the first embodiment and the spray device 6 provided with the spray nozzle 5, even if a plurality of fluids 60 are mixed and solidified, a plurality of fluids 60 are mixed in the process from the tank to the discharge port 15. The fluid 60 does not solidify. In this example, the fluid 61 and the fluid 62 are not mixed between the tank 31, the tank 32, the tip 110 of the innermost pipe 11, and the tip 120 of the intermediate pipe 12, and the tip 110 and the tip 120 are not mixed. After being discharged from the mixing field 16, the mixture is mixed in the mixing field 16. Therefore, clogging due to solidified material is unlikely to occur inside the supply pipe 21, the supply pipe 22, the innermost pipe 11, and the intermediate pipe 12.

[Embodiment 2]
Hereinafter, the spray head 1 of the second embodiment will be described with reference to FIG.
The basic configuration of the spray head 1 of the second embodiment is the same as that of the first embodiment. The main difference between the second embodiment and the first embodiment is that the innermost pipe 11 and the intermediate pipe 12 are not at the same position in the axial direction of the coaxial pipe 10 but are arranged in a staggered manner. Hereinafter, this difference will be described in detail, and detailed description of the configuration and effect overlapping with the first embodiment will be omitted.

In the coaxial tube 10 provided in the spray head 1 of the second embodiment shown in FIG. 5, the tip of the innermost tube 11 which is a tube located inside in the innermost tube 11 and the intermediate tube 12 which are two adjacent tubes. The 110 protrudes in the axial direction of the coaxial tube 10 from the tip 120 of the intermediate tube 12 which is a tube located on the outside. In this example, the tip 110 of the innermost pipe 11 projects from the tip 120 of the intermediate pipe 12 toward the discharge port 15. In the second embodiment, the protruding length h of the outermost pipe 14 is the distance between the tip 110 of the innermost pipe 11 and the tip 140 of the outermost pipe 14, which are the pipes most protruding toward the discharge port 15. Is.

When the coaxial pipe 10 includes a plurality of intermediate pipes 12, the positions of all the intermediate pipes 12 along the axial direction of the tip portions 120 of the coaxial pipes 12 are compared with the above positions of the tip portions 110 of the innermost pipes 11. Then, it is located far from the discharge port 15. That is, all the intermediate pipes 12 are retracted from the innermost pipe 11. When the coaxial tube 10 includes a plurality of intermediate tubes 12, the positions of the tip portions 120 of the two adjacent intermediate tubes 12 along the axial direction may be the same or different. For example, the above positions on the tip 120 of all the intermediate pipes 12 may be the same or different. When the positions of all the intermediate pipes 12 at the tip portions 120 are different, the amount of protrusion of each intermediate pipe 12 with respect to the other intermediate pipes 12 is larger as it is closer to the innermost pipe 11. When the coaxial tube 10 includes three or more intermediate tubes 12, the coaxial tube 10 may include an intermediate tube 12 having the same position and an intermediate tube 12 having different positions.

In the spray head 1 of the second embodiment, the innermost pipe 11 protrudes from the intermediate pipe 12 into the mixing field 16. Therefore, among the inner flow paths 103, the fluid 61 (FIG. 3B) from the first flow path 101 provided in the innermost pipe 11 is considered to be susceptible to the reflux vortex of the assist gas 64 (FIG. 3B). It is considered that the fluid 61 is likely to come into contact with the fluid from the flow path other than the first flow path 101 in the inner flow path 103, here, the fluid 62 from the second flow path 102, due to the reflux vortex. As a result, the fluid 61 and the fluid 62 are likely to be mixed in the mixing field 16.

[Test Example 1]
We investigated the fluid discharge state by simulation for three types of nozzles that discharge a plurality of fluids using assist gas and have different piping structures.

<Nozzle piping structure>
The nozzle of each sample includes one or a plurality of gas pipes for discharging the assist gas, and a plurality of fluid pipes for discharging a fluid other than the assist gas. The section of "head structure" shown in FIG. 6 shows a state in which the end face structure on the discharge port side of each sample nozzle is viewed in a plan view in the axial direction of the nozzle. Cross-hatching is attached to the end faces of the fluid pipe and gas pipe on the discharge port side.

Sample No. From 101 to No. In the nozzle 103, the fluid pipes are arranged so that the axes of the fluid pipes are parallel to each other.

Sample No. The nozzle 101 includes two double tubes in parallel. In each double pipe, one fluid pipe and one gas pipe are arranged coaxially. A gas pipe is provided on the outer circumference of the fluid pipe. Further, the axes of each double pipe are arranged so as to be parallel to each other.
One fluid tube has an inner diameter of 0.5 mm and an outer diameter of 0.8 mm. The inner diameter of the gas pipe located on the outer circumference of the fluid pipe is 1.0 mm.
The inner diameter of the other fluid pipe is 0.7 mm, and the outer diameter is 1.0 mm. The inner diameter of the gas pipe located on the outer circumference of this fluid pipe is 1.2 mm.
The ends of both fluid tubes are aligned in the axial direction of the nozzle.
The end of each gas pipe projects in the axial direction of the nozzle from the ends of both fluid pipes. The protruding length is 1 mm.

Sample No. The nozzle of 102 is the sample No. The gas pipe is changed to one for the nozzle of 101. That is, the sample No. The 102 nozzles include two fluid tubes arranged side by side in one gas tube. The outer shape of the gas pipe is a figure eight shape along two parallel fluid pipes.
The inner and outer diameters of each fluid pipe are the sample No. Same as 101. The size of the inner circumference of the gas pipe is such that a gas layer having a thickness of 0.2 mm is formed on the outer circumference of each fluid pipe except for a portion where both fluid pipes face each other.
The ends of both fluid tubes are aligned in the axial direction of the nozzle.
The end of the gas pipe projects in the axial direction of the nozzle from the ends of both fluid pipes. The protruding length is 1 mm.

Sample No. The nozzle of 103 is the sample No. It is provided with two pipe groups of two fluid pipes and one gas pipe described in 102. That is, the sample No. The 103 nozzles include a total of four fluid tubes. Except for the number of tube groups, sample No. The configuration of the nozzle of 103 is the sample No. It is the same as 102.

Sample No. Nozzle 1 includes the coaxial tube described in the first embodiment (see FIGS. 1 and 2). Briefly, the coaxial pipe is a triple pipe including a first fluid pipe which is the innermost pipe, a second fluid pipe which is an intermediate pipe, and a gas pipe which is the outermost pipe, and has a mixing field.
The inner diameter of the first fluid pipe is 0.5 mm, and the outer diameter is 1.0 mm.
The inner diameter of the second fluid pipe is 1.3 mm, and the outer diameter is 1.6 mm.
The end of the first fluid pipe and the end of the second fluid pipe are aligned in the axial direction of the coaxial pipe.
The inner diameter of the gas pipe is 1.9 mm. The protruding length h is 1 mm.

The nozzle of each sample is provided with an exodermis on the outer circumference of the gas pipe, which is the outermost pipe.

<Analysis conditions>
The analysis is modeled by the Volume of Fluid method using commercially available computational fluid dynamics (CFD) software.

The assist gas here is air. The fluid and air discharge range is a rectangular parallelepiped region having a volume of 10 mm × 10 mm × 21 mm. Hereinafter, among the surfaces constituting the rectangular parallelepiped, two surfaces facing each other and having a size of 10 mm × 10 mm are referred to as a first surface and a second surface, respectively. The nozzle of each sample is arranged on the first surface side and discharges the fluid toward the second surface. The second surface virtualizes the surface of the object. The tip of the nozzle of each sample protrudes 1 mm from the first surface and is arranged in the region of the rectangular parallelepiped. Therefore, the distance from the tip of the nozzle of each sample to the second surface is 20 mm. Further, the nozzle of each sample is arranged in the rectangular parallelepiped region so that the axis of the nozzle coincides with the center of the first surface. The contour diagram of FIG. 6 shows the region of the rectangular parallelepiped in a quadratic plane of 10 mm × 21 mm.

The fluid pipe and gas pipe provided in the nozzle of each sample discharge fluid and air to the above-mentioned discharge range at a predetermined flow rate (L / min), respectively.
The flow rate of each fluid is 1.5 mL / min. The flow rate of air is 1.44 L / mim. The air pressure, which is the pressure of the assist gas, is 0.06 MPa.
As for the fluid, the density, viscosity, and surface tension of each fluid were set assuming a two-component mixed type bioadhesive.

The gauge pressure is set to zero as the boundary condition in the discharge range described above.
For each of fluid and air, a certain amount of flow is created by steady-state analysis. This steady state analysis is the initial state. The time evolution is calculated up to a predetermined number of steps, with the time step width set to 0.1 milliseconds (ms), and the fluid state and the air flow state are analyzed.

FIG. 6 shows a contour diagram of the flow velocity of air, which is an assist gas discharged from the nozzle of each sample. Sample No. Regarding No. 1, a contour diagram of the “fluid abundance ratio” described later is also shown. Each contour diagram shown in FIG. 6 is selected from the created number of steps. In each contour diagram, the nozzles are located above the columns in the table. In each contour diagram, the upper white part is the sample No. In the samples other than 101, it is the exodermis, and the sample No. In 101, it is a gas pipe.

The contour diagram of the flow velocity of the assist gas shown in FIG. 6 is a grayscale version of the color-coded high and low flow velocity (m / s). Sample No. 6 in FIG. The grayscale scale bar shown in the left column of 101 is a scale bar common to all samples. The color scale scale bar before conversion is shown in blue to green to yellow to red in order from the bottom, and the gray scale scale bar corresponds to the above color scale scale bar. As shown in the scale bar, the threshold value in the contour diagram of the flow velocity is 0 or more and 15 or less. In the contour diagram of the flow velocity of the assist gas, the flow velocity of the fluid is indicated by a value in the vicinity of 0 m / s to 1.5 m / s.

Sample No. The contour diagram of the “fluid abundance ratio” of No. 1 is a grayscale conversion of the color-coded high and low proportions of the fluid in a certain region. The smaller the abundance ratio of the fluid in a certain region, the more blue it is before conversion, and in FIG. 6, it is shown in a dark color corresponding to this blue color. The higher the proportion of fluid in a region, the more red it is before conversion, and in FIG. 6, it is shown in a brighter color corresponding to this red. The threshold value of this contour diagram is 0 or more and 1 or less.

Sample No. 101-No. In the contour diagram of the assist gas of 103, the band-shaped region extending from the discharge port side to the second surface side described above is the assist gas. The mass existing in the band-shaped region is blue before conversion, and is a fluid indicated by a dark color corresponding to this blue color. Sample No. 101-No. It can be seen that all the nozzles of 103 discharge a mass of fluid, that is, a droplet, from the fluid tube. From this, the sample No. 101-No. In all of the 103 nozzles, when the pressure of the assist gas is small and the discharge distance is as short as 20 mm as in this test, it can be said that the two fluids are not mixed and adhere to the object at a high rate. That is, it can be said that it is difficult for the fluid to be discharged in the form of mist. Further, it can be said that the assist gas tends to flow in a wavy manner due to the large droplets, and the flow state of the assist gas is unstable.

Sample No. In the contour diagram of the assist gas of No. 1, the band-shaped region extending from the discharge port side to the second surface side described above is the assist gas. The substantially pentagonal mass shown in the area near the mixing field and discharge port of the coaxial tube is blue before conversion, and is a fluid shown in a dark color corresponding to this blue color. Sample No. It can be seen that in the nozzle No. 1, no droplets of the fluid can be seen, and the fluid is concentrated near the mixing field and the discharge port.

Sample No. In the contour diagram of "Abundance ratio of fluid" of No. 1, the mass shown in the region near the mixing field and the discharge port described above is red before conversion, and is a fluid shown in a bright color corresponding to this red color. .. Further, the linear streaks extending from the mass side to the second surface side are yellow to green before conversion, and are fluids shown in a relatively bright color corresponding to yellow to green. From the above mass, sample No. It can be seen that in the nozzle of 1, the fluid is mainly present near the mixing field and the discharge port. Further, from the above-mentioned linear streaks, it can be seen that the fluid mixed in the mixing field becomes fine particles, that is, mist-like, and is stably discharged. In this analysis, focusing on the above-mentioned mixing field, it has been confirmed that a rotating assist gas flow, that is, a reflux vortex is generated (see also FIG. 3A).

From these things, sample No. Nozzle 1 mixes a plurality of fluids in a mixing field near the discharge port to make the mixture an object even when the pressure of the assist gas is small and the discharge distance is as short as 20 mm as in this test. It is thought that it can adhere.

Also, sample No. In the nozzle No. 1, as shown in the contour diagram of the flow velocity of the assist gas, since the above-mentioned droplets do not exist, it can be said that the assist gas does not undulate and the flow state of the assist gas is stable. As a result, the sample No. Nozzle 1 is considered to be easy to discharge the mixture into a relatively narrow range, as shown in the contour diagram of "fluid abundance ratio". Such sample No. It is considered that the nozzle 1 can attach the mixture to a predetermined region of the object with high accuracy.

[Test Example 2]
Sample No. Nozzle 101 and sample No. For one nozzle, the ratio of two kinds of fluids mixed on the surface of the object was examined.

Using the above analysis results, when the discharge distance is 20 mm and a predetermined amount of fluid is discharged, the position where the fluid discharged from each fluid pipe adheres to the object 20 mm ahead and the amount of adhesion are determined. Ask for.

Sample No. In 101, the plane passing through the axes of the two fluid tubes is the x-plane, and the line of intersection with the x-plane on the surface of the object is the x-axis. The origin is the axis of the nozzle on the x-axis. For each fluid, the amount of adhesion at each point on the x-axis is calculated. The virtual amount standardized so that the integrated value of the adhesion amount is 1 is called the virtual fluid amount. Obtain a graph of the virtual fluid amount of each fluid and superimpose both graphs. The ratio of overlapping areas to the sum of the areas of both graphs is calculated as a percentage. This ratio is called the mixing ratio (%).

Sample No. Reference numeral 1 denotes an arbitrary straight line passing through the axis of the coaxial tube on the surface of the object, and on this straight line, the sample No. The mixing ratio (%) is obtained in the same manner as in 101.

As a result, the sample No. The mixing ratio of 101 is 68.7%. On the other hand, sample No. The mixing ratio of 1 is 98.8%. From this, the sample No. It was shown that the nozzle 1 can uniformly mix a plurality of fluids and adhere the mixture to the object when the discharge distance is as short as 20 mm even if the pressure of the assist gas is small.

[Test Example 3]
Sample No. Nozzle 102 and sample No. With respect to the nozzle of No. 1, two kinds of fluids were discharged to the object, and the mixed state of the fluids was examined.

Here, as the fluid, a commercially available petrolatum colored in red and a fluid colored in blue were prepared. As an object, a commercially available towel paper having excellent hygroscopicity was prepared. The pressure of the assist gas, here the air pressure is 0.06 MPa, and the fluid is discharged to a plurality of places on the towel paper. The mixed state of the fluid is evaluated by the color of the fluid applied to each part of the towel paper.

Sample No. When the 102 nozzles were used, not only the mixed color region 70 but also the blue region 71 and the red region 72 were present at each location of the towel paper, as schematically shown in FIG. 7B. From this, the sample No. It can be seen that at the nozzle 102, the two types of fluids are not mixed and adhere to the object. In FIGS. 7A and 7B, each region 70 to 72 is shown with hatching.

Sample No. When the nozzle of No. 1 is used, substantially only the mixed color region 70 exists in each part of the towel paper, as schematically shown in FIG. 7A. From this, the sample No. It can be seen that in one nozzle, a plurality of fluids are uniformly mixed and adhered to the object. Here, the blue region 71 was present in a ring around the mixed color region 70. The annular region 71 was generated by the petrolatum permeating after adhering to the towel paper due to the different speed of permeation of each petrolatum into the towel paper.

From Test Examples 2 and 3 described above, it was shown that a nozzle provided with a coaxial tube can more uniformly mix a plurality of fluids than a nozzle provided with a parallel tube described above.

[Test Example 4]
In the nozzle provided with the coaxial tube, the arrangement state of the tip of the outermost tube and the tip of the tube other than the outermost tube was changed, and the discharge state of the fluid was investigated.

Here, the sample No. Sample No. 1 was changed as follows for Nozzle 1. 104 and No. 105 were produced. Sample No. 104, No. None of the 105 nozzles provide the mixing field described above.

In the nozzle of sample No. 104, the tip of the outermost tube and the tip of the tube other than the outermost tube are lined up at the same position in the axial direction of the coaxial tube. That is, the tips of all the tubes constituting the coaxial tube are lined up on the same plane. Therefore, this nozzle has a flat discharge port.

In the nozzle of sample No. 105, the tip of the outermost tube is retracted from the tip of the tube other than the outermost tube. That is, the tip of the pipe other than the outermost pipe protrudes from the tip of the outermost pipe. The tips of the tubes other than the outermost tube are aligned at the same position in the axial direction of the coaxial tube. Therefore, the inner flow path through which the fluid other than the assist gas flows protrudes from the outer flow path through which the assist gas flows. In pipes other than the outermost pipe, the protruding length with respect to the tip of the outermost pipe is 1 mm.

A moving image of the state in which the fluid and the air, which is the assist gas, were discharged from the nozzles of each sample was captured by the camera from the direction orthogonal to the axial direction of the coaxial tube.

When the captured moving image was visually observed, the fluid was discharged without being atomized at the nozzle of sample No. 105 in which the innermost pipe and the intermediate pipe were projected from the outermost pipe, that is, the pipes other than the outermost pipe. It was. From this, the sample No. With the 105 nozzle, it is considered that the above-mentioned large droplets are likely to adhere to the object.

In the nozzle of sample No. 104 having a flat discharge port, the fluid becomes mist, but the discharge state is not well balanced. From this, the sample No. At the 104 nozzle, it is considered that the above-mentioned droplets may adhere to the object.

Sample No. In Nozzle 1, a plurality of fluids were mixed and discharged in the form of mist.

From Test Examples 1 to 4 described above, a nozzle provided with a coaxial tube, in which the outermost tube projects more than the other tubes and the outer flow path is the flow path of the assist gas, has a configuration in which a plurality of fluids are used. It was shown that it can be mixed uniformly. In addition, it was shown that the above configuration can discharge a mixture of a plurality of fluids in a mist form.

The present invention is not limited to these examples, and is indicated by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

For example, the number of intermediate pipes 12 may be two or more with respect to the first embodiment. In this case, the inner flow path 103 is also provided between the adjacent intermediate pipes 12.

1 Spray head 10 Coaxial tube, 11 Innermost tube, 12 Intermediate tube, 14 Outermost tube 110, 120, 140 Tip part, 146 Inner peripheral surface 15 Discharge port, 16 Mixing field, 19 Outer skin 100 Flow path, 103 Inner flow path , 104 Outer flow path 101 1st flow path, 102 2nd flow path 2 Nozzle base 20 Main body, 21,22 Supply pipe, 23 Intervening part, 24 Wall part 3 Fluid supply part 31, 32 Tank 4 Gas supply part, 40 Penetration Hole 5 Spray nozzle 6 Spray device 60,61,62 Fluid, 64 Assist gas 70,71,72 region, h Overhang length, D inner diameter

Claims (5)

1. A spray head with a coaxial tube
   The coaxial tube
   The innermost tube and
   With one or more intermediate tubes,
   The outermost tube and
   A plurality of flow paths provided inside the innermost pipe and between adjacent pipes inside and outside the pipe are provided.
   The plurality of flow paths
   The outermost flow path located on the outermost side,
   It is provided with a plurality of inner flow paths located inside the outer flow path.
   The outer flow path is configured to allow the assist gas to flow.
   Each of the plurality of inner flow paths is configured to allow a fluid other than the assist gas to flow.
   The tip of the outermost pipe projects in the axial direction of the coaxial pipe from the tip of the innermost pipe and the tips of all the intermediate pipes.
   Spray head.
2. Of the innermost pipe and the one or more intermediate pipes, the tips of two adjacent pipes are aligned at the same position in the axial direction, or of the two adjacent pipes located inside. The spray head according to claim 1, wherein the tip portion projects in the axial direction from the tip end portion of a tube located on the outside.
3. The spray head according to claim 2, wherein the tip of the innermost pipe and the tips of all the intermediate pipes are aligned at the same position in the axial direction.
4. The spray head according to any one of claims 1 to 3.
   With a nozzle base connected to the spray head
   The nozzle base includes a plurality of supply pipes and has a plurality of supply pipes.
   Each of the plurality of supply pipes is connected between the innermost pipe and the one or a plurality of intermediate pipes and a plurality of tanks for storing each of the fluids in a separated state.
   spray nozzle.
5. The spray head according to any one of claims 1 to 3, or the spray nozzle according to claim 4.
   A plurality of tanks for storing each of the fluids.
   Spray device.

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