JPH0796102B2 - Method for manufacturing fan-shaped spray nozzle and molding core - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a nozzle that ejects fan-shaped sprays in the absence of air, and in particular, manufactures a nozzle that has an action of preventing the occurrence of tail when spraying paint. The present invention relates to a core for molding a method and its nozzle material.

[Conventional technology]

As an airless fan-shaped spray nozzle, a concave hole consisting of a dome-shaped concave surface and a cylindrical flow path continuous to the dome-shaped concave surface is provided in the nozzle main body in a rear open state, and a groove having a V-shaped cross section is formed at the front end of the nozzle main body. It is common to engrave so as to intersect the recessed hole at an appropriate depth under the front open state, and to provide a lip-shaped injection port formed by the intersection of the recessed hole and the groove.
In addition, for spraying paint, it is necessary to manufacture a wear-resistant material, for example, a superhard material such as cemented carbide or ceramic. Therefore, in manufacturing the material, a core suitable for forming a recess is provided. It is general to use a molding die to powder-mold an intermediate material mainly having a nozzle having a concave hole, sinter it, and grind the V-shaped groove with a grinding wheel.

However, when spraying the paint, a surplus portion called a tail is likely to be formed at both end edges of the fan-shaped spray, and in order to prevent the generation of this tail, a fillet is formed at the boundary between the dome-shaped concave surface and the tubular flow path. The non-annular corner portion is formed, and the groove bottom of the V-shaped groove is cut to a depth that coincides with or slightly intersects the annular corner portion.

Therefore, in order to form the annular corner portion by molding, it is conceivable to provide the molding core with a ridge portion adapted to the formation of the corner portion.

[Problems to be Solved by the Invention]

When manufacturing the spray nozzle of the above model, the spray size may change depending on the type of curve of the dome-shaped concave surface, the size of the opening diameter of the concave surface, the angle of the groove, the shape of the groove, etc. Due to the change in the discharge rate, they are selected and manufactured so as to match the desired specifications, but in order to manufacture a nozzle of the type that prevents the occurrence of tails (hereinafter referred to as no tail nozzle), While it is necessary to strictly define the depth, not only is the opening diameter of the concave surface as small as 0.2 to 1.0 mm, but a groove is formed by grinding from the outside of the blind hole using a grinding wheel. In addition, since the nozzle-based intermediate material is a black-skinned material obtained by sintering, it is slightly distorted or has uneven dimensions, so it has an appropriate depth when grinding grooves. Because it is extremely difficult to engrave, Excessively happens when deeply engraved with the defective product, it is impossible to play.

The number of types of nozzle specifications that can be obtained from a material that is molded by one molding die is limited by the shape and angle of the groove, but is actually a few types.

Therefore, an object of the present invention is to provide a method for manufacturing a no-tail nozzle capable of obtaining various specifications from a material molded by one molding die, and another object is to easily reproduce a defective product. Another object of the present invention is to provide a manufacturing method of a tail nozzle which is suitable for thick film coating, and to provide a manufacturing method which can easily obtain a tail nozzle having a large discharge amount. Is to provide a manufacturing method for a no-tail nozzle that does not hinder even a slight error in alignment when hitting a groove, and yet another object is to provide a molding core that is easy to manufacture. It is in.

[Means for Solving the Problems]

In order to achieve the above object, the present invention provides a convex mold surface adapted to mold a concave surface such as a dome or a semi-cylindrical shape, and a cylindrical mold surface adapted to a cylindrical flow path. Mainly for nozzles by using a core with multiple stages provided with a horizontal obtuse ridge near the connection between Nozzle formed in multiple stages under the condition that the obtuse angle corners without fillet near the connecting part between the concave surface and the cylindrical flow path are appropriately separated in the front-rear direction by sintering after molding the material To the extent that the material for the main body is manufactured and a groove in the front open state is formed at the front end of the material after sintering and the groove bottom is aligned or slightly intersects with the corner of any of the above-mentioned stages in the vertical direction. It is engraved on.

The corner portion can be selected from various shapes such as an annular shape, an arc shape, a parabolic shape, and a linear shape. Especially, in the case of a linear shape, the length is formed to be relatively long so that the centering of the groove is small. Not only will there be no problem even if there is a deviation, but a nozzle with a large discharge amount suitable for thick film coating can be obtained by forming the groove shape into an inverted trapezoid with a narrow bottom.

〔Example〕

FIGS. 1 to 3 show an example of a notch nozzle obtained by the manufacturing method of the present invention, in which a nozzle main body 1 is formed with a dome-shaped concave surface 2 and a cylindrical flow path 3 connected to the concave surface. The hole 4 is opened rearward and the nozzle main body 1
At the front end, a groove 5 having a V-shaped cross-section in the front open state is carved so as to properly intersect with the recessed hole 4 in a vertical direction, and a substantially lip-shaped orifice type injection port 6 is opened. In this respect, there is no difference from the usual fan-shaped spray nozzle of this kind, but in the illustrated nozzle, there is no fillet-shaped obtuse angle and a mutual diameter in the vicinity of the connecting portion between the dome-shaped concave surface 2 and the tubular flow path 3. Different annular corners 7a, 7b are formed in a state where a space is maintained in the front-rear direction, and the groove 5 is provided at a depth such that the bottom thereof slightly intersects the annular corner 7a. It is a thing.

In order to manufacture the nozzle of FIGS.
As shown in the figure, the convex mold surface adapted to mold the dome-shaped concave surface 2
11 and a cylindrical mold surface 12 adapted for molding the cylindrical flow path 3, and an annular obtuse ridge 13 near the connecting portion between both mold surfaces 11 and 12.
a lower mold 15 having a core 14 in which a and 13b are provided so as to maintain a constant interval in the axial direction, and a substantially Ω-shaped mold surface 16 adapted for molding the outer shape of the nozzle main body 1 near the tip. There is an upper mold 17
And an outer mold 19 having a cylindrical outer circumference 18 adapted for molding of the outermost peripheral surface of the nozzle main body 1 and sliding guide of the upper mold, and the lower mold 15 and the outer mold 19 are joined as shown in the drawing. After filling the cylindrical mold surface 18 of the outer mold 19 with ultra-hard powder material such as tungsten carbide, the upper mold 17 is strongly guided while being guided by the cylindrical mold surface 18 of the outer mold 19 as shown in FIG. Since it is made to advance, the molded product obtained by this is sintered to manufacture the material of the nozzle main body 1, and then the groove 5 is ground by the diamond grinding wheel 20 having a V-shaped cross section as shown in FIG. is there.

Regarding the grinding of the groove 5, its depth is important in terms of preventing the generation of tails, and the optimum depth is in a state where the optimum depth is slightly crossing the corner portion 7a or 7b, and the groove bottom is sharp. In the case, 1/100 to 1/10 of the major diameter of the lip-shaped nozzle 6 is desirable, and when the groove 5 is an inverted trapezoid, the groove bottom has a corner 7a or
It is suitable that it is the same as 7b or the degree of intersection is within 1/100 of the major axis of the lip-shaped nozzle 6.

For the core 14 for forming the corners 7a and 7b,
The dome-shaped convex mold surface 11 and the cylindrical mold surface as shown in FIGS.
12 is a convex die surface 11 mainly composed of a core, and the vertically symmetrical position toward the rear is cut obliquely forward to form an arc-shaped obtuse ridge 13a, 13b.
May be formed, and as shown in FIG. 9 and FIG. 10, the upper and lower parts of the cylindrical mold surface 12 having a dome-shaped convex mold surface 11 and the cylindrical mold surface 12 are mainly parallel to each other. In addition to reducing the shape to an oval cross-section, the vertical symmetrical position of the dome-shaped convex mold surface 11 toward the rear is reduced obliquely forward to form an arc-shaped obtuse ridge 13a and a straight obtuse ridge 13b. Alternatively, as shown in FIGS. 11 and 12, there is a semi-cylindrical convex mold surface 11 and a square cylindrical mold surface 12, and the upper and lower parts of the convex mold surface 11 mainly composed of the core are located on the rear side of the curved portion. It is also possible to reduce the symmetrical position in a diagonally forward direction and form linear obtuse ridges 13a, 13b parallel to each other.

In the above embodiment, the corner portion is provided in two steps, that is, the ridge portion is provided in two steps in the front and rear, but a plurality of steps may be provided,
For example, as the core 14 for forming a recessed hole, three-stage annular ridges 13a, 13b, 13c are provided as shown in FIGS. 13 and 14, or an arc-shaped ridge is provided as shown in FIGS. 15 and 16. 13a, the linear ridge 13b, and the circular ridge 13c may be provided in three stages, or as shown in FIGS. 17 and 18, the circular ridge 13a and the linear ridge 13c.
13b and 13c may be provided in three stages, and also FIG. 19 and FIG.
The straight ridges 13a, 13b, 13c may be provided in three stages as shown in 0, and the nozzle main body 1 having the corner portions provided in three stages is manufactured, and three stages are provided as shown in FIG. Corners 7a, 7b, 7c
By providing the groove 5, it is possible to form three appropriate positions of the depth when the groove 5 is engraved, and it is possible to remarkably expand the range of specifications of the nozzle that can be manufactured with one kind of material.

The angle of the corners 7a, 7b, 7c is in a practical range of 150 ° to 175 °, but a good result can be obtained by selecting 160 ° to 170 °.

As the shape of the groove 5, various shapes such as U-shape, square shape, W-shape, and trapezoidal shape can be selected in addition to the V-shape and the inverted trapezoidal shape. In molding the material, a molding die similar to the one described above was adopted, injection holes were provided at appropriate positions, and the ceramic raw material slurry was injection-filled or injected to be molded and then sintered. Good.

〔effect〕

As described above, according to the present invention, the corner portion which is important for preventing tail generation is formed by molding in a plurality of front and rear steps, and the corner portion at any stage is selected to obtain a desired specification. Since the nozzle can be manufactured, it is possible to easily obtain a remarkably versatile no-tail nozzle from one type of material, thus reducing the types of molding dies and nozzle materials and simplifying inventory management of both. In addition to being able to do so, it is economical because it is easy to control the inventory quantity.

In addition, forming the corners in a straight line is not only advantageous in terms of preventing the tail when engraving a groove with a wide groove bottom, but also aligns during engraving work regardless of the shape of the groove. Since there is no problem even if it is misaligned, the defective rate of the product is significantly reduced.

Furthermore, since the corners are provided in multiple steps, when engraving the grooves according to the specifications corresponding to the corners of the first step, the grooves may be excessively deep and may not be formed. Even if it becomes a good product,
It is convenient to use as a product having specifications corresponding to the corners of the next stage, and defective products can be reused, which is extremely economical.

[Brief description of drawings]

In the drawings, FIGS. 1 to 3 show an example of a fan-shaped spray nozzle manufactured by the method of the present invention. FIG. 1 is a vertical side view, FIG. 2 is a front view, and FIG. Fig. 4, Fig. 4 is a vertical sectional side view of the molding die used for carrying out the method of the present invention, Fig. 5 is a vertical sectional side view of the molding die in the molding system, and Fig. 6 is a sectional view showing a grooved state. , FIG. 7 and FIG. 8 are side and oblique views, respectively, of the core in another molding die, FIG. 9 and FIG. 10, FIG. 11 and FIG. 12, FIG. 13 and FIG. Figures 15 and 16, Figure
FIGS. 17 and 18, FIG. 19 and FIG. 20 are a side view and a perspective view, respectively, showing only the core of another molding die separately, and FIG. 21 is the degree of groove engraving. FIG. 3 is a cross-sectional plan view for explaining only a main part of FIG. 1 …… Nozzle main 2 …… Concave surface 3 …… Cylindrical flow path 4 …… Concave hole 5 …… Groove 7a …… Corner corner 7b …… Corner corner 7c …… Corner corner 11 …… Convex mold surface 12 …… Cylindrical surface 13a …… Ridge 13b …… Ridge 13c …… Ridge 14 …… Core

Claims (4)

[Claims] 1. A convex mold surface adapted to mold a concave surface, a cylindrical mold surface adapted to mold a cylindrical flow path communicating with the concave surface, and both the convex mold surface and the cylindrical mold surface. Using a molding die with cores provided in multiple stages so that relatively close intervals in the front-rear direction are maintained with vertical obtuse ridges in the horizontal direction near the joints of the surfaces. A nozzle-based material is molded and then sintered to produce a nozzle-based material in which multiple obtuse corners with no fillet are formed in the front-rear direction in the vicinity of the connection between the concave surface and the tubular flow path. And a fan-shaped groove formed by opening the front end of this material in a front open state to a depth such that the bottom of the groove coincides with or slightly crosses the corner of any one of the above-mentioned stages. Manufacturing method of spray nozzle. 2. The method for producing a fan-shaped spray nozzle according to claim 1, wherein at least one step of the ridge portion of the molding core has a linear shape. 3. The method for producing a fan-shaped spray nozzle according to claim 1, wherein a molding die having three ridges in the molding core is used. 4. A convex mold surface adapted to mold a concave surface and a cylindrical mold surface adapted to mold a cylindrical flow path communicating with the concave surface, and the convex mold surface and the cylindrical mold surface. A core for molding a fan-shaped spray nozzle material, in which a plurality of horizontal obtuse ridges are provided in the vicinity of the connecting portion with the vertical symmetry so that relatively close intervals are maintained in the front-rear direction.