JPS6147139B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an airless spraying device that sprays pressurized liquid in a fan shape, and is characterized in that so-called tail generating elements at both ends of the fan-shaped jet are eliminated by suction airflow. Hereinafter, various aspects illustrated in the accompanying drawings will be described in detail.

As an airless spray nozzle to which the present invention is applied, for example, as shown in the figure, a nozzle body 1
A type is adopted in which a dome-shaped recess 2 is provided in a rear open state, and a V-shaped groove 3 is provided at the front end in a front open state so as to intersect with the recess 2 to form an orifice type nozzle 4. However, the present invention is not limited thereto, and can be applied to any other types where so-called tails are likely to occur, such as drum head nozzles and the like.

As a special configuration of the present invention for the orifice type nozzle, for example, as shown in FIGS. In addition to being fixed in a liquid-tight state by the member 7, an annular groove 8 is carved on the outer circumferential side near the front end of the holder 6, and the annular groove 8 is communicated with the inner side corresponding to both ends of the groove 3 in the nozzle. In addition, a connecting member 11 having an air intake passage 10 is attached to the outer periphery of the holder 6, and an air intake means is connected to the air intake passage 10 to allow outside air to flow through the air intake openings 9, 9. The pressurized liquid is ejected from the nozzle spout 4 while suctioning the jet, thereby eliminating the tail-generating elements t that tend to occur at both ends of the fan-shaped jet F from the nozzle 4 by the suction airflow opposing and contacting the direction of flight of the tail. According to the experimental results, when applying a melamine resin paint that tends to generate tails under a low pressure of 20 kg/cm ² , the coating pattern without the special structure of the present invention is as shown in Figure 3a. However, the coating pattern obtained by using the same nozzle and applying the special configuration of the present invention is the third one.
As shown in figure b, it has the effect of not generating any tail at all, and by adopting an injector-type intake means, it is possible to pressurize the air by several kg/cm ² using a commonly used compressor. It can be carried out using air.

The embodiment shown in FIGS. 4 and 5 is a specific example in which an injector type is adopted as the intake means, and the intake passage 10 of the connecting member 11 is formed diagonally forward and is connected to the pressurized air supply pipe 12. Air supply path 1
1 and 2, except that the air intake passages 3 and 13 are provided in the forward direction intersecting the intake passage 10 at an acute angle, and the exhaust ports 14 thereof are opened at positions adjacent to both ends of the fan-shaped jet flow F from the nozzle. With a similar structure, the pressurized gas flowing through the air supply passages 13, 13 generates an airflow in the direction of the arrow in the intake passage 10 under the action of the injector, thereby not only preventing the occurrence of tail, but also It is possible to further prevent the occurrence of tails due to forward exhaust from the exhaust port 14, and it is also possible to omit the treatment of a small amount of spray accompanying the intake air.

6 and 7, the air inlet 9 in the embodiments of FIGS. 1 and 2 faces both edges of the fan-shaped jet flow F, whereas the entire circumference of the tip of the nozzle body 1 is A connecting member 11 is provided, and for this purpose, a connecting member 11 is provided.
An inwardly facing annular regulating piece 15 is provided at the front end of the nozzle, and the annular gap between the regulating piece 15 and the front end of the nozzle body 1 or the front end of the holder 6 is used as the intake port 9.
In addition, the intake port 9 and the annular groove 8 are communicated through a large number of ventilation holes 16, and the other configurations are the same as those in FIGS. 1 and 2, so the same reference numerals are given and the explanation will be omitted.

It is also preferable that the air intake means of the embodiments shown in FIGS. 6 and 7 be of an injector type, and that the exhaust air be used for an air curtain formed around the spray. For this purpose, as shown in FIG. A large number of air intake passages 10, 10 are provided diagonally forward in a circular row, and air supply passages 13, 1 communicating with the pressurized air supply pipe 12 are provided.
3 is provided in a forward direction intersecting the intake passages 10, 10 at an acute angle, and the exhaust air is blown out from the annular or elliptical exhaust port 14 in the forward direction toward the outer periphery of the spray, thereby preventing the spray from scattering over a wide range. At the same time, it is possible to effectively prevent influences from outside during painting, that is, the adhesion of water vapor or dust, as well as turbulence of the spray caused by air currents.

As the intake means, various devices other than the injector can be adopted, and for example, a rotary type exhaust device, a reciprocating type exhaust device, etc. may be selected as appropriate.

As explained above, according to the present invention, the droplets of the tail generating element are suctioned or finely pulverized into atomization by the intake air opposing the flight of the tail generating element, effectively preventing the generation of tail, and furthermore, the generation of a fan-shaped jet This effect can be expected to promote atomization of the paint, making it suitable for coating.

[Brief explanation of the drawing]

In the drawings, FIGS. 1 and 2 are a longitudinal sectional side view and a front view, respectively, showing a spraying device of the present invention in one embodiment, and FIGS. 3a and 3b are a spray pattern by a conventional device and a spraying pattern by the device of the present invention, respectively. 4 and 5 are longitudinal sectional side views and front views of other embodiments, respectively, and FIGS. 6 and 7 are longitudinal sectional side views and partially cutaway front views of still further embodiments, respectively. FIG. 8 is a longitudinal sectional side view of yet another embodiment. 1... Nozzle body, 2... Concave, 3... Groove, 4
...Nozzle, 6...Holder, 8...Annular groove, 9...
Intake port, 10... Intake path, 11... Connection member, 1
2... Air supply pipe, 13... Air supply path, 14... Exhaust port, 15... Annular regulating piece, t... Tail generation element, F... Fan-shaped jet, T... Tail.

Claims (1)

[Scope of Claims] 1. A liquid spraying device characterized in that an air intake port is provided near at least both edges of a fan-shaped jet ejected from an airless spray nozzle. 2. The liquid spraying device according to claim 1, wherein the intake port is provided around the entire circumference of the fan-shaped jet. 3. The liquid spraying device according to claim 1 or 2, which is provided with an injector-type suction means. 4. Claims 1 or 2 include an injector type intake means and the exhaust gas is sprayed onto both ends of the fan-shaped jet from the spray nozzle.
The liquid spray device described in section. 5. The invention according to claim 1 or 2, which is provided with an injector-type intake means and in which the exhaust air is ejected so as to form an air curtain around the fan-shaped jet from the spray nozzle. Liquid spray device. 6. The liquid spraying device according to claim 1 or 2, which employs a nozzle having an orifice-type nozzle formed by intersecting a dome-shaped recess and a groove.