JPH0236305B2 - BERUGATAKAITENMUKASHIKITOSOKINYORUIROGAETOSOHOHO - Google Patents

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 paint machine, which allows the bell cup portion to be easily and completely cleaned during color change, and does not cause coating defects such as color spots after color change.

[Conventional technology]

In recent years, in the painting of automobile bodies, etc., the use of color lots has been promoted in order to reduce the loss of paint and cleaning thinner when changing colors.

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

[Problem that the invention seeks to solve]

However, in color change coating using a bell-type coating machine, the following problem still remains even if the color lot is used as described above.

In other words, in the case of painting with a bell type paint machine,
If you paint the same color on 10 or 20 cars in a row, the bell cup area will get very dirty. When painting car bodies transported by a conveyor using a bell-type paint machine, the bell cup continues to rotate after the painting of one car body is completed until the painting of the next car body starts. However, no paint was discharged. Therefore, when painting the next car body, paint starts to be dispensed while the bell cup is rotating at high speed, which disrupts the atomization pattern of the paint particles, causing damage to the outer periphery of the bell cup. Paint particles stick. This phenomenon of adhesion of paint particles occurs every time the paint is applied to each body, so if 10 to 20 cars are painted in the same color, a large amount of paint particles will adhere to the bell cup. If such a large amount of paint particles adheres to the bell cup, it becomes difficult to completely clean the bell cup when cleaning the paint sprayer when changing to the next color, and therefore, paint particles that adhere to the bell cup during painting after changing colors become difficult. The unwashed paint before the color change peels off due to the shaping air.
There are problems such as paint defects such as so-called color spots caused by being sprayed together with the paint after color change.

In view of the above-mentioned points, the present invention provides a color change painting method that can completely wash and remove the pre-color change paint 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 in the middle of painting the same color. The present invention relates to a color change coating method using a bell-shaped atomizer, characterized in that a bell cup portion of the atomizer is cleaned.

〔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 Figures 1 and 2, 1 is a bell cup, 2 is an air motor, 3 is a 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 cup cleaning nozzle. This is the cleaning liquid outlet.

The bell cup 1 is composed of a rotating disk 11 and a truncated conical cup 12. As shown in Fig. 2, this bell cup 1 is driven by an air motor 2 and rotates at high speed to atomize the paint discharged from the paint supply nozzle 3. Painting is performed using pattern A. C is shaping air for regulating the atomization pattern. Note that the shroud 7 is retracted when performing the painting work in this manner.

If you want to paint the same color on an object such as an automobile body under the conditions shown in Fig. 2 and change the color, clean the paint supply piping system and bell cup 1 of the bell-type atomizer and paint the paint as before. Switch.

In this case, the bell-type atomizer is cleaned in the following manner.

As shown in FIG. 1, the shroud 7 is advanced during cleaning. In this state, the cup front cleaning nozzle 4 is positioned so that it can spray cleaning liquid (usually cleaning thinner is used) onto the front inner surface of the bell cup 1, and the cup back cleaning nozzle 5 sprays cleaning liquid onto the back surface of the bell cup 1. positioned so that it can be

First, a cleaning liquid is supplied to the paint supply pipe by switching the valve of the paint supply system, and the paint is extruded from the paint supply nozzle 3 to clean the paint supply pipe, and then the bell cup 1 is cleaned. The paint adhering to the inner surface of the cup 12 and the rotating disc 11 is washed off by the cleaning liquid sprayed from the cup front surface cleaning nozzle 4 and the cup interior cleaning nozzle 6. Further, the paint adhering to the back surface of the cup 12 is washed off by the cleaning liquid sprayed from the cup back surface cleaning nozzle 5.

Note that the cleaning liquid and the paint washed off together with the cleaning liquid are discharged from a discharge port 8 provided at the lower part of the shroud 7.

As mentioned above, after cleaning the bell-type paint sprayer,
The paint after color change is supplied from a paint supply nozzle 3 to perform painting after 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 under the conditions shown in Fig. 2, for example, after the painting of one car body is finished, until the painting of the next car body starts, the bell cup is not used. 1 is rotating, but paint is not being discharged from the paint supply nozzle 3. Next, when painting an automobile body, the paint starts to be discharged while the bell cup 1 is rotating at high speed, so the atomization pattern of the paint particles is disturbed for a while, as shown in pattern B, and as a result, the paint The rate at which particles adhere to the back surface of the bell cup 1 increases.

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 by spraying a cleaning liquid from the cup front side cleaning nozzle 4, the cup back side cleaning nozzle 5, and the cup inside cleaning nozzle 6, as in the case of color change. 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 is cleaned in the middle of painting the same color to prevent a large amount of paint from adhering to the bell cup 1, so that the bell cup 1 can be easily and completely cleaned when changing colors. Therefore, painting defects such as color spots will not occur during painting after color change.

In the present invention, cleaning of the bell cup 1 during the same color painting may be carried out as appropriate to facilitate cleaning at the time of color change, but in the case of painting automobile bodies, it is generally necessary to wash the bell cup 1 every 4 to 6 cars.

Although the case where a bell-type atomizer for side painting is used has been described above, the case where a bell-type atomizer for dot painting is used is basically the same.

〔Effect of the invention〕

In color change painting using a bell-type paint machine, 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.

Claims (1)

[Claims] 1 When painting while changing colors using a bell-type rotary atomizing paint machine, in addition to cleaning the paint machine when changing colors, clean the bell cup part of the paint machine during the same color painting process. A color change coating method using a bell-shaped rotary atomizing coating machine.