JPH0580272B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a spray nozzle, particularly an orifice that produces a film-like spray pattern.

[Conventional technology]

An orifice as shown in FIG. 4 is conventionally known as an orifice for a spray nozzle that can produce a film-like spray pattern. This orifice has a diametrically long bulge 12 in the center of the orifice plate 11.
, and an orifice hole 13 is formed at the top of the bulged portion 12.

In the conventional orifice as described above, the orifice hole 13 is opened by rotating the cutter 14 and moving the bulge 1 as shown in FIG.
2 by cutting the top part horizontally in a direction perpendicular to 2.

[Problem to be solved by the invention]

As in the past, the orifice hole 13 is inserted into the cutter 1.
When opened by 4, its rotation direction (see arrow)
Burrs 15 and 16 are formed on the inside and outside of the hole 13 along the inside and outside of the hole 13.

In order to remove the burrs 15 and 16, a so-called deburring operation is performed after cutting.
In this case, the burr 16 formed on the outside of the hole 13 can be removed, but the burr 15 formed on the inside thereof is difficult to remove.

In the orifice, the orifice hole 13
Since the shape of the spray film directly affects the shape of the spray film,
It is undesirable for the burr 15 as described above to remain inside the hole 13.

Furthermore, since cutting is performed using the cutter 14, it is difficult to freely select the minute orifice hole 13 and the spread angle of the spray pattern.

Furthermore, if the top of the bulging portion 12 has a curved shape as shown in FIG. 6, by cutting the portion near the top, both end surfaces 17, 17 of the orifice hole 13 will become parallel to the orifice plate 11, The angle β between the end surfaces 17, 17 and the inner surface of the bulging portion 12 is small and sharp. Therefore, there is a problem that the orifice hole 13 is easily worn out.

[Means for solving problems]

In order to solve the above problems, the present invention forms a rectangular orifice hole in the center of an orifice plate by punching, and then punches out a portion including the orifice hole from one surface to the other. A protrusion having a central portion of the orifice hole is formed, and inner wall surfaces of the orifice hole on two opposite sides of the protrusion are directed inward to the orifice hole so as to have a certain angle with respect to the orifice plate. It is designed so that it slopes downward.

〔Example〕

1 to 3 show the pressing process. First, as shown in FIG. 1, an orifice plate 1 is formed by punching out a metal plate in a circular shape, and a rectangular orifice hole 2 is formed in the center of the plate by punching. Next, as shown in FIG. 2, the portion including the orifice hole 2 is punched out from the back surface toward the front surface to form a protrusion 3 having a constant width a ₁ and having the orifice hole 2 in the center. At the same time, both ends of the protrusion are expanded somewhat to form the positioning portion 4.

The opening angle α ₁ of the orifice hole 2 cannot be larger than 180°. That is, as shown in FIG.
5 is inclined downwardly toward the inside of the orifice hole 2 so as to have a constant angle β ₁ with respect to the orifice plate 1 . Therefore, the angle β ₂ between each inner wall surface 5, 5 and the tangent 1 drawn to the inner surface of the protrusion 3 at its inner end is an angle that includes the above-mentioned angle β ₁ .

When the above angle β ₁ becomes zero (that is, the opening angle α ₁ is 180°), the angle of the peripheral wall of the orifice hole 2 (the angle β ₂ - _{β 1} in Fig. 2) becomes sharp, and the orifice hole 2 becomes early. The disadvantage is that it wears out. Therefore, β ₁ is set to have a predetermined angle larger than a certain value.

When the protrusion 3 is formed, the radius of curvature of the outer surface becomes larger than the radius of curvature of the inner surface at the apex thereof, so that the inner circumferential wall of the orifice hole 2 is deformed to have a constant opening angle α ₁ . This opening angle α ₁ determines the spread angle of the spray pattern.

In addition, the difference in the radius of curvature between the inside and outside of the protrusion 3 is
The smaller the width, the larger the width, so if the width a ₂ of the protrusion 3 is set smaller than the width a ₁ as shown in ~ in Fig. 3, the opening angle becomes α ₂ (α ₂ > a ₁ ), and the It is larger than in the case of Figure 2. Therefore, by freely selecting the width of the protrusion 3, the orifice hole 2 can be formed with an arbitrary opening angle.

In addition, although the opening angle of the orifice hole 2 in the width direction of the protrusion 3 changes depending on the width of the protrusion 3, the dimension in the length direction of the protrusion 3 remains unchanged. (Figure 2,
(See Figure 3). If the orifice hole 2 made by punching is originally circular, the cross-sectional shape of the fan-shaped spray flow will be thicker on both sides than in the center, and the spray and distribution will be uneven. When the orifice hole 2 is rectangular as in the embodiment, both side portions and the central portion have a uniform thickness, resulting in uniform spray distribution.

〔effect〕

As described above, in this invention, the protrusion is formed by punching including the part of the square hole drilled in the disc, thereby forming the protrusion having a deformed orifice hole. Depending on the diameter of the hole initially drilled and the width of the protrusion, an orifice hole with an arbitrary opening angle can be easily formed.

In addition, since the orifice hole is initially formed by punching, there is almost no burr generation, and even minute holes can be drilled with high precision.
It is possible to manufacture orifices of uniform quality.

Furthermore, since the hole initially drilled in the disk is square,
It has superior uniformity in spray pattern distribution compared to circular holes, and when forming protrusions, the inner wall surfaces on the two opposing sides of the protrusions of the orifice hole have a constant angle β ₁ with respect to the orifice plate. The wear resistance of the orifice hole can be improved.

[Brief explanation of drawings]

Figures 1 to 3 show the steps of the manufacturing method; Figure 1 is a plan view, Figure 2 is a cross-sectional view, Figure 2 is a plan view, and Figure 2 is a cross-section taken along line A-A. The same figure is a sectional view taken along the line B-B, the same figure is an enlarged view, the figure 3 is a plan view, and the same figure is a cross-sectional view taken along the line A-B.
4 is a perspective view of the conventional example, 5 is a partially enlarged sectional view of the same as above, and 6 is a partially enlarged sectional view of another conventional example. FIG. 1... Orifice plate, 2... Orifice hole, 3
... Projection, 5 ... Inner wall surface.

Claims (1)

[Claims] 1 Form a rectangular orifice hole in the center of the orifice plate by punching, and then punch out the part including the orifice hole from one surface to the other to form a protrusion having the orifice hole in the center. and an inner wall surface of the orifice hole on two opposite sides of the protrusion is inclined downwardly toward the inside of the orifice hole so as to have a certain angle with respect to the orifice plate. Orifice manufacturing method.