JPH0798166B2 - Distribution-controlled fan-shaped spray nozzle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a nozzle for obtaining a fan-shaped spray having a controlled non-uniform distribution, and more particularly to a nozzle suitable for airless spraying of high viscosity paint.

[Conventional technology]

As a conventional nozzle for obtaining a fan-shaped spray having a controlled non-uniform distribution, there is a so-called drum head nozzle as described in, for example, JP-A-50-70915. The shape is boat-shaped, and the inner surface of the orifice is formed in an irregular shape so that a fan-shaped spray having a sawtooth distribution characteristic curve can be obtained.

[Problems to be Solved by the Invention]

In the above-mentioned prior art, the purpose thereof is a nozzle for obtaining a fan-shaped spray having a sawtooth distribution characteristic curve, and therefore, according to the structure, a fan-shaped spray having another special distribution characteristic curve cannot be obtained. A deformed sawtooth characteristic different from a simple sawtooth characteristic, for example, a substantially horizontal inverted R-shaped distribution characteristic curve (hereinafter referred to as an R-shaped characteristic) or a substantially W-shaped shape in which the lower sawtooth portion is increased in a U shape. Nozzle capable of obtaining a fan-shaped spray having a distribution characteristic curve (hereinafter referred to as W-shaped characteristic) is desired.

Therefore, an object of the present invention is to provide R
Another object of the present invention is to provide a nozzle for an airless spray that can obtain a fan-shaped spray having a character shape or a W shape characteristic, and another object is to provide a nozzle whose distribution characteristic can be adjusted.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention provides a concave hole having a dome-shaped concave surface at the front end in the nozzle main body in a rear open state, and matches the diameter of the dome-shaped concave surface at the front end of the nozzle main body. A relatively deep vertical groove that is open to the front in the vertical direction and two relatively shallow lateral grooves that are orthogonal to the vertical groove and that are out of the diameter of the dome-shaped concave surface are provided so as to intersect the concave surface. To form an almost square-shaped orifice type nozzle, and instead of the two lateral grooves, 4
The cutouts are provided at the points to form an almost square-shaped orifice type orifice.

[Action]

According to the above-mentioned configuration, the fan-shaped spray having a substantially uniform distribution ejected from the basic rip-shaped nozzle formed by the intersection of the concave surface and the vertical groove, has an R-shaped characteristic or It is possible to obtain a W-shaped spray.

As a method of measuring the characteristics, the spray of a corrugated paper is sprayed for a certain period of time on a corrugated paper surface having a large number of uneven lines parallel to the minor axis direction of the substantially oval coating pattern obtained by applying the fan-shaped spray from the vertical direction. A curve drawn by the length of the liquid flowing down in the groove may be obtained.

〔Example〕

Hereinafter, the nozzle of the present invention will be described in detail with reference to the illustrated embodiments.

Referring to the embodiment shown in FIGS. 1 to 3, a nozzle main body 1 made of a hard material such as cemented carbide is provided with a concave hole 4 formed of a dome-shaped concave surface 2 and a tapered cylindrical passage 3 in an open rearward state. In addition, a vertical groove 5 having a V-shaped cross section is provided at the front end of the nozzle main body 1 so that its groove bottom is close to or slightly intersects with the passage 3 under the condition that the vertical groove 5 is aligned in the diametrical direction of the dome-shaped concave surface 2. In addition to being provided relatively deep to the extent that the dome-shaped concave surface 2 is deviated from the diametrical direction, the vertical groove 5
Two lateral grooves 6a and 6b which are orthogonal to each other are provided so as to relatively shallowly intersect the dome-shaped concave surface 2 to form an almost square-shaped orifice type nozzle hole 7, and the lateral grooves 6a and 6b If the depths are different from each other, R as shown in FIG.
It is possible to obtain a spray having a letter-shaped characteristic, and if both lateral grooves 6a and 6b are equally formed, a spray having a W-shaped characteristic as shown in FIG. 5 can be obtained.

The embodiment shown in FIGS. 6 to 8 is not provided with the lateral groove in the above-mentioned embodiment, but instead is provided with the rim of the lip-shaped injection port formed by the intersection of the dome-shaped concave surface 2 and the vertical groove 5. By forming two pairs of arcuate notches 8a, 8a and 8b, 8b facing each other by lapping or electric discharge machining, it is possible to obtain a spray having the characteristics shown in FIG. 4 or 5.

Regarding the shapes of the vertical groove 5 and the horizontal grooves 6a, 6b, FIG. 9 (A)
Various shapes can be selected, such as a V-shape like, a U-shape like (B), an inverted trapezoid like (C), and a square like (D). The R-shaped characteristic and the W-shaped characteristic can be adjusted based on the combination of the depth and the radius of curvature of the dome-shaped concave surface 2, and similarly, the shape of the cutouts 8a and 8b is not limited to the arc shape. , (A), (B), (C), and (D) of FIG. 9, various shapes can be selected, and the distribution characteristics can be adjusted by the shape and size.

Further, in the above-mentioned embodiments, the passage 3 of the nozzle main body 1
It is desirable to attach a pre-orifice 9 in the range of 1/2 to 2 times the distribution area of the injection port 7 close to the upstream side of the nozzle, and to prevent the occurrence of tails, improve atomization, adjust distribution characteristics, etc. Especially, by appropriately selecting the distribution area of the pre-orifice 9 to the same extent as the distribution area of the injection port 7, it is possible to obtain a spray having a typical R-shaped characteristic.

〔The invention's effect〕

As described above, according to the present invention, two horizontal grooves or two pairs of cutouts are provided to the lip-shaped nozzle formed by the intersection of the dome-shaped concave surface and the vertical groove, thereby forming a substantially cutout. With a remarkably simple structure that forms a letter-shaped nozzle,
It has the effect that the distribution of the spray can be controlled to easily and reliably inject a fan-shaped spray with R-shaped characteristics or W-shaped characteristics. Also, by installing a pre-orifice near the nozzle injection port, the occurrence of tail can be prevented. There is an advantage that the effects of atomization and distribution control can be improved, and it is suitable for coating the inner surface of a stepped cylindrical container while rotating it.

[Brief description of drawings]

In the drawings, FIGS. 1 to 3 show claims 1 and 3.
Which shows a nozzle of an embodiment corresponding to
The figure is a vertical side view, FIG. 2 is a vertical front view, FIG. 3 is a plan view mainly of a nozzle, and FIGS. 4 and 5 are diagrams showing spray distribution characteristic curves by the nozzle of the present invention separately, FIG. 8 to FIG. 8 show an embodiment corresponding to claims 2 and 3, wherein FIG. 6 is a vertical sectional side view, FIG. 7 is a vertical sectional front view, FIG. 8 is a plan view mainly of a nozzle, and FIG. It is a schematic diagram showing other examples of the shape of a vertical groove, a horizontal groove, and a notch. 1 …… Nozzle main 2 …… Dome shape concave surface 3 …… Passage 4 …… Concave hole 5 …… Vertical groove 6a …… Horizontal groove 6b …… Horizontal groove 7 …… Injection port 8a …… Notch 8b …… Notch 9 …… Pre-orifice

Claims (3)

[Claims] 1. A nozzle main body is provided with a recessed hole consisting of a dome-shaped concave surface and a passage in a rear open state, and a vertical groove is formed at the front end of the nozzle main body so as to coincide with the diametrical direction of the dome-shaped concave surface. In addition, the groove bottom is provided relatively deep so that it is close to or slightly intersects with the passage, and two lateral grooves orthogonal to the vertical groove are provided under the condition that they are deviated from each other in the diametrical direction of the dome-shaped concave surface. A distribution control type fan-shaped spray nozzle, characterized in that it is provided on the dome-shaped concave surface so as to intersect relatively shallowly to form a substantially square-shaped orifice type nozzle. 2. A nozzle main body is provided with a concave hole consisting of a dome-shaped concave surface and a passage in an open rearward state, and a vertical groove is formed at the front end of the nozzle main body so as to coincide with the diameter direction of the dome-shaped concave surface. In addition, the groove bottom is formed relatively deep so that it is close to the passage or slightly intersects with the passage to form a lip-shaped jet port, and two pairs of notches are provided at the edges of the lip-shaped jet port near both ends. The distribution control type fan-shaped spray nozzle is characterized by forming an almost square shaped orifice nozzle. 3. The distribution area of the injection port is upstream, near the recessed hole.
3. The distribution control type fan-shaped spray nozzle according to claim 1, further comprising a pre-orifice having a flow area of 1/2 to 2 times.