JPH0326370A - Method for applying liquid or melt - Google Patents

Abstract

PURPOSE:To decrease the splashing of excess mists by providing an object which has a surface wider than the surface of materials to be coated and moves cyclically on the rear surface of the materials to be coated and sticking the oversprayed mists onto this object. CONSTITUTION:Liquid or the like is sprayed SP1 from a spray nozzle 1 and the atomized particles are stuck and applied on the surfaces of the materials O1, O1a,... to be coated. Since the size of the spray coating patterns is larger than the individual surfaces of the objects O1, O1a,... to be coated, the oversprayed particles passes the spacings S between the objects which are continuously fed and passes along both sides of these materials O1, O1a,... as well and arrive at the surface of a conveyor belt 7 traveling below the same, thus sticking thereto. The mists sticking onto the conveyor belt 7 gather to form a liquid layer Pl. The liquid is turned back and is scraped Pl1 by a scraper 8 or the like, by which the liquid is accumulated PL in a liquid collecting layer 9 below (Pl1), from which the liquid is returned to a tank and is reutilized.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method of applying a liquid or melt.

[Conventional technology]

Conventionally, in coating by liquid atomization, such as spray coating, a spray nozzle (
A large amount of surplus mist (SPm) is scattered around the nozzle (111) and the object to be coated (0...), which not only harms the working environment, but also
), the gun (112), and the inner wall surface of the booth (113), etc., and they aggregate densely to form a liquid (Ld), which is then dripped (Ldi) onto the surface of the object to be coated (OiS) to form a coating surface. This had the disadvantage of contaminating the surface.

[Problem to be solved]

In order to solve the above-mentioned problems, various measures have been taken in the past. A commonly used method is to guide the mist-containing air that fills the booth to the outside through a duct. In the same method, is that? Not only are these devices relatively large-scale, but
It was also necessary to clean the air purifying equipment and the inner walls and filters of the ducts, which was very expensive.

Originally, during spraying work, as shown in Figure 10A, the part of the spray pattern (spiz) where the particle size of the atomized particles and their distribution density are highly uniform is focused on the surface of the object to be coated. It is preferable to apply by spraying on top. If the surface to be coated is "D"-rrD",
The coating pattern is as shown in FIG. 10B. That is, in the central part (SPc, 2) of the coating pattern, relatively fine particles with uniform particle sizes are dispersed with a relatively uniform distribution density. The particles become coarser and the distribution becomes non-uniform towards the outside (SPaxi) of the same coating pattern. Therefore, when applying with the spray nozzle (121) fixed, the object to be coated should follow the above spray pattern (S
It is desirable to keep it within the central part (SPc1■) of P1z). Therefore, other parts of the splay pattern will be oversprayed. These oversprayed particles become excess mist that scatters and fills the booth.

If these overspray particles can be prevented from scattering, excess mist inside the booth can be suppressed accordingly.

The motivation for the present invention was to catch oversprayed particles and further reduce the scattering of excess mist.

? Means for Solving the Problems] The gist of the present invention is that in a coating method using a liquid or molten mist generator, a surface area wider than the object to be coated is placed on the back side of the object to be coated, which is placed in the flow direction of the generated mist. A circulating object is provided, and the oversprayed mist is deposited on the surface of the object to prevent unnecessary excess mist from occurring, and the adhering mist is collected by a removal tool or the like. This is a method of applying the product while applying it.

The method of the present invention will be explained with reference to the drawings. Figures 1 and 2
Please refer to the figure (top view of the above figure). The figure shows the most common spray nozzle (1) as a mist generator. Liquid etc. are sprayed from the spray nozzle (1) (SPL). The atomized particles are applied to the object to be coated (01,0
1a,...) is adhered and coated on the surface. However, in general, the size of the spray application pattern is
The oversprayed particles, which are larger than the respective surfaces of the objects 01a, . . .
a, .

The amount of adhesion varies depending on the air spray method, airless spray method, etc., but about half of the cases are coated. Therefore, the amount of mist scattered within the booth is reduced accordingly, and the amount of floating mist is also reduced. Therefore, as before,
There is also less chance that excess mist will adhere to the nozzle, gun, etc., drip in a dense manner, and stain the surface of the object to be coated.

In this way, the mist adhering to the surface of the conveyor belt (7) is densely formed into a liquid layer (pm), which makes a U-turn and is scraped off by a scraper (8) or the like at a certain point along its circulation path. The liquid is collected (Pfii) and stored in the liquid collection tank (9) below (PL). It is collected and returned to the tank (not shown in the drawing) for reuse.

In addition, the lower surface of the object to be coated (Ox*Cha,...),
It is desirable that the distance (C) between the conveyor belt (7) and the upper surface is as small as possible. Specifically, OLII
It is desirable to keep I1 to 10 mm. The reason is to prevent sprayed particles from going around. If the object to be coated is long, the gap (CO
) can be easily brought close to O.

In addition, even if the objects to be coated are single items, if they are continuously supplied, as shown in Fig. 4, a similar type Conveyor belt for transporting objects to be coated (47. 48
) to continuously supply and discharge the single-piece type coated object onto the above-mentioned mist catch conveyor belt (37), and bring the gap (C,) close to O as in the case of the above-mentioned long object. You can also do it.

It goes without saying that in the present spray coating, if electrostatic coating is performed, the generation of excess mist can be further reduced.

In the above description, a spray nozzle has been cited as a typical mist generating device, but other devices such as centrifugal or ultrasonic mist generating devices can also be applied in the same manner as in the above spray nozzle.

〔Example〕

First Embodiment In the above description, the spray was directed downward, but in this embodiment, it is directed laterally as shown in FIG. Catching the oversprayed mist on the conveyor belt is the same as in each of the above examples.

The second embodiment is a case in which the spray direction is directed upward. The conveyor belt (67) catches the oversprayed amount (spas) as described above (see FIG. 6).

Third Embodiment In each of the above embodiments, a method was described in which the oversprayed mist was caught by a conveyor belt, but the method is to catch it by a roll (77) (see FIG. 7).

Fourth Embodiment In each of the above-mentioned embodiments, the surface of the object to be coated was sprayed from one direction, but for the object to be coated on both sides, as shown in FIG. S P
9) You can catch the mist while applying it.

〔effect〕

According to the method of the present invention, during spray coating using a mist generating device such as a liquid or molten material, for example, a spray nozzle, most of the excess mist that is oversprayed onto the object to be coated and generated around the object to be coated is caught, In addition to contributing to the improvement of environmental hygiene at work sites, the above-mentioned surplus mist adheres to the inner wall of the nozzle, gun, or booth, becomes liquefied, and drips, staining the surface of the object to be coated. Therefore, it is possible to apply the product while suppressing it. Furthermore, the mist caught can be collected and returned to the tank of the spray device for reuse.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the method of the present invention. Figure 2 is the upper diagram.
II-11A'''' Plan view Figure 3 is an explanatory diagram when the gap between the long object to be coated and the conveyor belt approaches O. Figure 4
Figure 5 is an explanatory side view of the first embodiment. Figure 6 is an explanatory side view of the second embodiment. Figure 7 is an explanatory side view of the second embodiment. Figure 8 is an explanatory side view of the fourth embodiment. Figure 9 is an explanatory diagram of the conventional spray coating method. Figure 10A is an explanatory diagram of the state of the spray pattern. Figure 10B is the upper diagram "D. Explanation of main symbols on the “1D” floor plan

Claims (10)

[Claims] (1) In a method of applying mist from a liquid or molten mist generator, the object to be coated (O_
1, O_1a, ...), and is provided facing the mist generating device (1), and in the same direction as the traveling direction of the object to be coated (O_1, O_1a, ...). Alternatively, the mist (SP_0_1) flowing over the object to be coated (O_1, O_1a, . . . ) is caught on the surface of the circulation moving body (7) moving in the opposite direction, and the mist generating device (1) and the object to be coated (O_1, O_1
A method for applying a liquid or molten material, characterized in that the application operation is carried out in a state where excess mist generated around (a, . . . ) is further reduced. (2) The above-mentioned object to be coated (O_1
, O_1a, ...), and removes the caught mist with a removal tool (8) or the like at a certain point in the circulation path of the circulation moving body (7). The method for applying a liquid or melt according to claim 1, wherein the liquid or melt is collected and returned to a liquid or melt tank for a mist generator for reuse. (3) The method for applying a liquid or melt according to claim 1, wherein the mist generating device is a spray nozzle. (4) The method for applying a liquid or melt according to claim 1, wherein the circulating body is a conveyor belt (7). (5) Gap between the back surface of the object to be coated and the top surface of the conveyor belt (
2. The liquid or melt coating method according to claim 1, wherein the coating is carried out while maintaining C_n or C_0_1) at a thickness of 0 mm to 10 mm. (6) A method for applying a liquid or melt according to claim 1, characterized in that the application is performed while applying static electricity. (7) Mist flow (S) from the mist generator (51)
The liquid or melt coating method according to claim 1, wherein the P_5) direction is horizontal. (8) Mist flow from the mist generator (61) (S
P_6) The method for applying a liquid or melt according to claim 1, wherein the direction is upward. (9) The liquid or melt coating method according to claim 1, wherein the circulating body is a roll (77). (10) A plurality of mist generators (81, 91) are connected to the objects to be coated (O_8, O_8a, O_8a,
O_9, O_9a,...) and apply the mist streams (SP_8, SP_9) at the same time with different phases, while applying the overlapping mist streams (S
The method for applying a liquid or melt according to claim 1, characterized in that the method comprises catching P_0_8, SP_0_9).