JP2556352B2 - Two-fluid spray nozzle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a two-fluid spray nozzle suitable for applying paint or the like.

[Conventional technology]

The conventional two-fluid spray nozzle is, as conceptually shown in FIG. 6, a paint nozzle 21, a needle valve 22 for opening and closing the paint nozzle 21,
It has a pressurized spray gas outlet 23. The needle valve 22 is pressed against the paint nozzle by the spring 24 to close the nozzle. During spraying, the pressurized gas is in line 25.
To the piston chamber 27 to open the needle valve 22, and at the same time pressurized gas from the line 26 is ejected from the ejection port 23,
The atomized liquid, for example paint, supplied from line 28 is atomized. In detail, there are various nozzle tip structures, but they are basically as described above, and they have common drawbacks. That is, since the needle valve and its drive mechanism are provided near the spray nozzle,
The size of the spray nozzle is large. Further, since the shape is complicated, the processing accuracy is limited and the manufacturing cost is high. For this reason, it is not easy to make a large number of spray nozzles having the same spray pattern, and it is unsuitable for the usage of arranging a plurality of spray guns together.

[Problems to be Solved by the Invention]

The present invention has a simple structure, can be miniaturized, has high accuracy,
It is an object of the present invention to provide a novel spray nozzle which can be manufactured at low cost and is suitable for a usage different from the conventional one.

[Means for solving the problem]

The spray nozzle of the present invention is, in a two-fluid spray nozzle, a central thin tube for supplying a fluid to be sprayed, the tip of which is open only in the axial direction, concentrically existing with the central thin tube, and the outer diameter of the central thin tube. A flow for a pressurized spray fluid communicating with an outer shell having an inner diameter larger by 0.3 to 0.6 mm and having a tip extending to substantially the same position as the tip of the central thin tube, and an opening in a side wall of the outer shell. The outer diameter of the central thin tube and the outer diameter of the outer diameter of the central thin tube, which closes the gap between the outer diameter of the central thin tube and the outer diameter of the outer shell at a position opposite to the tip of the central thin tube from the opening. A two-fluid spray nozzle having a tube having a diameter.

The present invention will be described with reference to FIG. In FIG. 1, 1 is a central thin tube. The side of the central thin tube opposite to the nozzle tip (hereinafter referred to as the base) communicates with the central hole of the valve receiver 2, and by opening and closing the valve 3, the fluid to be jetted, for example, from the paint or ink reservoir 4 is supplied. To be done. In the present invention, either a spray gun of the type in which the fluid in the reservoir 4 is slightly pressurized, or a spray gun of the type in which the fluid is not pressurized but is simply sucked and sprayed by the fluid ejected under pressure is used. Good. The inner diameter of the central thin tube is, for example, 0.1 to 0.3 mm, and the wall thickness can be around 0.1 mm.

An outer shell 5 exists concentrically with the outside of the central thin tube. The shell 5 can be a tube as shown, or a wall of holes drilled in the block as shown in Figure 3 below. The inner diameter of the outer shell 5 is larger than the outer diameter of the central thin tube 1, and an annular space of 0.3 to 0.6 mm exists between them. The tip of the outer shell 5 is located at substantially the same position as the tip of the central thin tube 1, and more specifically, it projects by 0.2 to 0.5 mm, for example. Or it can be withdrawn.

The side wall of the outer shell 5 is provided with an opening 6 for a pressurized spraying fluid for spraying the sprayed fluid and a flow path 7 for the fluid which is continuous with the opening 6. It is also possible to provide a plurality of openings 6 and a plurality of channels 7. The position of the opening 6 is not particularly limited, and when it is desired to make the nozzle thin, it can be provided at a position of, for example, 5 to 50 mm from the tip of the nozzle. The diameter of the openings can be around 1 mm, for example.

The central thin tube 1 and the outer shell 5 are located closer to the base than the opening 6.
The closing member 8 is provided to fill the gap. The closing member 8 has a role of filling the gap and a role of concentrically fixing the pipe 1 and the pipe 5. Therefore, it is preferable that at least a part of the closing member 8 is in the vicinity of the opening 6, for example, in the vicinity of 0.5 to 2 mm. The closing member 8 is a tube having an inner diameter substantially the same as the outer diameter of the central thin tube and an outer diameter substantially the same as the outer diameter. If this is a pipe and the outer shell 5 is also a pipe, the spray nozzle will be composed of a total of three pipes, which facilitates production and increases the processing accuracy. Further, the nozzles can be bent in any direction, which is convenient for arranging a plurality of nozzles in a dense arrangement.

FIG. 1 shows an example in which the tip of the tube serving as the closing member 8 ends near the opening, but due to the centering and strength of the tubes 1 and 5, the closing member tube 8 extends close to the tip of the nozzle. May be. In such a case, the closure member 8 is provided with a groove, as shown in sketch in FIG. 2, through which the pressurized fluid is ejected.

In the use of the spray nozzle of the present invention, a pressurized atomizing fluid, such as pressurized air, is ejected from the nozzle tip through the flow passage 7, the opening 6 and the gap between the tubes 1 and 5. At the same time or with an appropriate time delay, the valve 3 is opened so that the fluid to be sprayed, such as paint or ink, is sprayed from the nozzle tip through the tube 1. When stopping the atomization, the valve 3 is closed and, at the same time or after an appropriate time delay, the flow of the pressurized atomizing fluid is stopped. It should be noted that the valve 3 is merely conceptually drawn, and may be a known means such as a valve that is moved electromagnetically or pneumatically, or an electrostrictive element, and is not limited to the illustrated shape. . For example, those described in Japanese Utility Model Publication No. 62-29094 can be used.

In the present invention, unlike conventional spray nozzles,
It is not necessary to install the valve at the tip of the nozzle, and the position of the valve is set to some extent from the tip of the nozzle, for example, 5 m in order to make the nozzle thinner.
It is preferable that they are separated by m or more, and it is particularly preferable that they are located in the vicinity of the outer base portion on the side opposite to the tip of the nozzle.

Although FIG. 1 shows an example in which the flow passage 7 for the pressurized atomizing fluid, for example, the pressurized air, is formed of a pipe, the flow passage 7 may be a space formed in a block. In FIG. 3, 9 is a block made of metal, and 7 is a flow path for pressurized air formed in the block. A plurality of said flow paths,
It communicates with one common channel 10, which communicates with the pumping tank and further with the compressor. In the process of forming the flow path 7 in the block, if a hole is formed in one surface of the block and then the surface is sealed with, for example, a blind screw 11, the production is easy. In FIG. 3, reference numeral 12 denotes a hole into which the closing member 8 and the intermediate thin tube 1 are inserted, the diameter of which is substantially equal to the outer diameter of the closing member 8. Alternatively, as shown in FIG. 1, the nozzle tip having a separate outer shell 5 made of a tube can be inserted into the hole 12. In order to control each spray nozzle independently in the embodiment as shown in FIG. 3, the valve on the side of the fluid to be sprayed is opened and closed.

The spray nozzle of the present invention can be used to continuously spray a paint or ink, or to spray intermittently to create a discontinuous pattern. As one mode of use, the spray nozzle of the present invention shown in FIG. 1 can be made extremely thin and small, and can be bent. Therefore, three or more spray nozzles are collectively arranged in a dense arrangement to form one spray unit. For example, as shown in FIG. 4, a nozzle storage unit 13 composed of several blocks
The three spray nozzles 14 of the present invention can be closely arranged therein. The spray nozzle 14 is bent in the space 15, and the three nozzle tips are in contact with each other. In the drawing, 10 is a common flow path for the pressurized atomizing fluid, for example, pressurized air. Reference numeral 16 is a supply pipe for the fluid to be sprayed, for example, a paint, and an opening / closing valve and the like are present above (not shown). FIG. 5 shows another embodiment in which the numbers in the figure indicate the same as in FIG. The three spray nozzles 13 of the present invention are housed in a pipe 17, a gap between the pipe 17 and the spray nozzle shell 5 is a pressurized air flow path 7, and pressurized air is supplied from a pipe 18. . On the upper side (not shown), an opening / closing valve for each spray nozzle is provided. Since the three spray nozzles are thin, the distance between the centers of the nozzles is extremely small.
mm. Therefore, even if sprayed from any nozzle, it is possible to apply to almost the same range of the object to be coated. Therefore, by supplying red, yellow, and blue paints or inks to the nozzles and controlling the spray from the nozzles independently, a desired color can be applied to a desired position on the object to be coated. Alternatively, a plurality of spray nozzles can be arranged in a line to obtain a coating pattern of any width. Conventionally, since the change of the width of the coating pattern depends on the aperture of the nozzle, it is difficult to prepare with good reproducibility, and it cannot be automated.

As described above, it is possible to use a plurality of spray nozzles as one unit, in addition to the reason that the spray nozzles of the present invention are small and can be densely arranged, the variation in accuracy among the nozzles is small. There is also a reason that it can be manufactured. Since the nozzle of the present invention has a simple structure which is basically made of the straight tube 1 and the outer shell 5, and preferably the tube 8, the processing accuracy can be extremely high. For example, the gap between the tube 1 and the outer shell 5 is large. The error of the depth is ± 5 μm. On the other hand, in the conventional spray nozzle shown in FIG. 6, the error of the pressurized gas ejection outlet 23 is about ± 30 μm.
Considering that this accuracy has a great influence on the uniformity and deformation of the coating pattern, the above-mentioned difference in accuracy is significant.

〔The invention's effect〕

The spray nozzle of the present invention can be extremely miniaturized, for example, the tip size can be 1 to 4 mm. It is usually about 15 mm for conventional spray nozzles.

The spray nozzle of the present invention has a simple structure and can be manufactured accurately. Also, the manufacturing cost is low.

Since the spray nozzle of the present invention mainly comprises a thin tube, it can be bent in any direction or formed as a block body. Therefore, a plurality of nozzles can be densely arranged, and arbitrary different colors can be applied to predetermined places.

[Brief description of drawings]

FIG. 1 is a sectional view conceptually showing a spray nozzle of the present invention. FIG. 2 is a sketch drawing showing a different mode of the member 8. FIG. 3 is a partially cutaway sketch showing an example in which a plurality of spray nozzles of the present invention are arranged. 4 and 5 are cross-sectional views showing an example in which the spray nozzles of the present invention are densely arranged. FIG. 6 is a sectional view of a conventional spray gun. In the figure, each number indicates the following. 1 ... Central thin tube, 5 ... Outer shell 6 ... Opening 7 ... Flow path for pressurized spray fluid, 8 ... Closure member

Claims (2)

(57) [Claims] 1. In a two-fluid spray nozzle, a central thin tube for supplying a fluid to be sprayed, the tip of which is open only in the axial direction, exists concentrically with the central thin tube, and is 0.3 from the outer diameter of the central thin tube. An outer shell having a large inner diameter of ~ 0.6 mm and a tip extending to substantially the same position as the tip of the central thin tube, a flow path for a pressurized spray fluid communicating with an opening in a side wall of the outer shell, Where the gap between the outer diameter of the central thin tube and the outer diameter of the central thin tube is closed at a position in the direction opposite to the tip of the central thin tube than the opening, an inner diameter substantially the same as the outer diameter of the central thin tube and an outer diameter substantially the same as the inner diameter of the outer shell. A two-fluid spray nozzle having a holding tube. 2. The two-fluid spray nozzle according to claim 1, wherein the valve for opening and closing the central thin tube is located in the vicinity of the outer base portion opposite to the nozzle tip.