JPS62136266A - Color-replacing painting method by bell shaped rotary atomizing type painting machine - Google Patents

Abstract

PURPOSE:To facilitate washing at the time of the replacement of a color by preventing the excessive contamination of a bell cup, by washing the bell cup on the way of the painting of the same color. CONSTITUTION:In painting an automobile body with the same color, a bell cup 1 is washed on the way of the painting of the same color at intervals of about 4-6 automobiles. The washing in this case is performed by injecting a washing solution from a coup front surface washing nozzle 4, a cup back surface washing nozzle 5 and a cup interior washing nozzle 6 by the same way as that at the time of color replacement. However, because the extrusion washing of the paint in the piping of a paint supply system is not performed, no paint loss is generated. As mentioned above, by preventing the adhesion of a large amount of the paint to the bell cup 1 by washing the bell cup 1 on the way of the painting of the same color, washing at the time of the replacement of the color becomes easy and the generation paint lumps is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color change coating method using a bell-type rotary atomizing coating machine. More specifically, the present invention relates to a color change coating method using a bell-type rotary atomizing coating machine, in which the bell cup portion can be easily and completely cleaned during color change, and coating defects such as color spots do not occur after color change.

[Conventional technology]

In recent years, when painting automobile bodies, etc., color lots have been promoted in order to reduce the loss of paint and cleaning thinner during color changes.

Further, for painting automobile bodies, etc., a bell-type rotary atomizing paint machine (hereinafter referred to as a bell-type paint machine), which atomizes and applies paint using a bell cup that rotates at high speed, is often used.

[Problem that the invention seeks to solve]

However, in color change coating using a bell-type atomizer, the following problem still remains even if the color lots are made as described above.

In other words, when painting with a bell-type paint machine, if you paint the same color on 10 to 20 car bodies in a row,
The bell cup becomes extremely dirty.

When painting car bodies transported by a conveyor using a bell-type paint machine, the bell cup rotates between the time one car body finishes painting and the next car body starts painting. However, no paint is being ejected. Therefore, when starting to paint the next car body, paint will begin to be discharged while the bell cup is rotating at high speed, which will disrupt the atomization pattern of paint particles and cause damage to the outer periphery of the bell cup. Paint particles stick. Since this phenomenon of adhesion of paint particles occurs every time the painting of each body is started, if 10 to 20 cars are painted in the same color continuously, a large amount of paint particles will adhere to the bell cup. This large amount of paint particles on the bell cup makes it difficult to completely clean the bell cup when cleaning the paint sprayer when changing to the next color, and therefore, the bell cup may be difficult to clean completely when cleaning the paint sprayer when switching to the next color. The unwashed paint on the cup before the color change is peeled off by the shaving air and sprayed together with the paint after the color change, causing problems such as so-called color spots and other paint defects.

In view of the above-mentioned points, the present invention provides a color change painting method which can completely wash and remove the paint before color change adhering to the bell cup by the normal cleaning operation of the paint machine at the time of color change. .

[Means for Solving the Problems] The present invention provides, when painting while changing colors using a bell-type paint machine, in addition to cleaning the paint machine at the time of color change, cleaning the paint machine during the same color painting process. The present invention relates to a color change coating method using a bell-type coating machine, which is characterized by cleaning the bell cup portion of the coating machine.

〔Example〕

Next, the present invention will be explained based on the drawings.

FIG. 1 is a cross-sectional side view of essential parts of an example of a bell-type atomizer used in the present invention, and FIG. 2 is a state diagram of the bell-type atomizer shown in FIG. 1 during painting work. The bell-shaped atomizer shown in FIGS. 1 and 2 is for side painting.

In Figure 1 and Figure f52, (1) is a bell cup,
(2) is the air motor, (3) is the paint supply nozzle, (4)
is a cup front cleaning nozzle, (5) is a cup back cleaning nozzle, (6) is a cup interior cleaning nozzle, (7) is a shroud, and (8) is a cleaning and liquid discharge port.

Bell cup (1) is a rotating disk 01) and a truncated conical cup 0
It consists of 21. As shown in Fig. 2, this bell cup (1) is driven by an air motor (2) and rotates at high speed, thereby opening the paint supply nozzle (3).
It works to atomize the paint discharged from the atomizer, and in a steady state, painting is performed with a normal atomization pattern (A). (C
) provides shaving air to regulate the atomization pattern. Note that when painting in this way, the shroud (sword) is set back.

If you want to paint the same color on an object such as an automobile body under the conditions shown in Figure 2 and change the color, you can use the paint supply piping system of the bell-type atomizer and the bell cup (
Perform 1) cleaning and change of paint.

In this case, the cleaning process is similar to that of a bell-type paint sprayer.

As shown in Figure 1, the shroud (
7) is advanced. In this state, the cup front cleaning nozzle (
4) is a cleaning solution (usually
The cup back cleaning nozzle (5) is located so that it can spray a cleaning thinner (cleaning thinner is used), and the cup back cleaning nozzle (5) is located on the bell cup (1).
is positioned so that cleaning liquid can be sprayed onto the back surface of the machine.

First, the cleaning liquid is supplied to the paint supply pipe by switching the valve in the paint supply system, and the paint is pushed out from the paint supply nozzle (3) to clean the paint supply pipe, and then the bell cup (
Perform the cleaning step 1). The paint adhering to the cup (the inner surface of the cup 121 and the rotating disk opening) is washed away by the cleaning liquid sprayed from the cup front cleaning nozzle (4) and the cup interior cleaning nozzle (6). In addition, the cleaning liquid sprayed from the cup back cleaning nozzle (5) cleans the cup (+2).
The paint adhering to the back side of the machine will be washed off.

Note that the cleaning liquid and the paint washed off together with the cleaning liquid are discharged from the discharge port (8) provided at the bottom of the shroud.

As described above, after cleaning the bell-type coating machine, the paint after the color change is supplied through the paint supply nozzle (3) to perform the painting after the color change.

In the present invention, in addition to the above-mentioned cleaning at the time of color change, the bell cup (1) is cleaned in the middle of painting the same color.

As mentioned above, when painting car bodies in the same color in the state shown in FIG. Although the bell cup (1) is rotating, no paint is being discharged from the paint supply nozzle (3). When starting painting the next car body, the bell cup (1) is rotating at high speed and the paint starts to be discharged, so for a while the atomization pattern of the paint particles will be similar to, for example, pattern (B). As a result, paint particles are more likely to adhere to the back surface of the bell cup (1).

Therefore, in the present invention, the bell cup (1) is cleaned during the same color painting. In this case, the bell cup (1) is cleaned using the cup front cleaning nozzle (4), similar to when changing colors.
This is done by spraying cleaning liquid from the cup back surface cleaning nozzle (5) and the cup interior cleaning nozzle (6). However, since the paint in the pipes of the paint supply system is not extruded and cleaned, there is no loss of paint.

In this way, in the present invention, the bell cup (1
) to prevent a large amount of paint from adhering to the bell cup (1), making it easy and complete to clean the bell cup (1) when changing colors. There will be no paint defects such as color spots during subsequent painting.

In the present invention, cleaning of the bell cup (1) during the same color painting may be done as appropriate to facilitate cleaning when changing colors, but when painting automobile bodies, it is usually necessary to wash the bell cup (1) every 4 to 6 cars. good.

Although the case where a bell-shaped atomizer for side coating is used has been described above, the case where a bell-shaped atomizer for top coating is used is basically the same.

〔Effect of the invention〕

During color change painting using a bell type paint sprayer, by cleaning the bell cup in the middle of painting the same color and preventing excessive dirt on the bell cup, cleaning at the time of color change can be done easily and completely. This makes it possible to prevent problems such as color spots during painting when changing colors.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional side view of essential parts of an example of a bell-type rotary atomizing coating machine used in the present invention, and Fig. 2 is a state of the bell-shaped rotary atomizing coating machine shown in Fig. 1 during painting work. It is a diagram. (Main symbols in the drawing) (1): Bell cup (3): Paint supply nozzle (4), (5), (6): Cleaning nozzle (3): Paint supply nozzle

Claims (1)

[Claims] 1 When painting while changing colors using a bell-type rotary atomizer, in addition to cleaning the paint machine when changing colors, the bell cup part of the paint sprayer should be cleaned in the middle of painting the same color. A color change painting method using a bell-shaped rotary atomizing paint machine.