JPS61118173A - Two-color spray painting method - Google Patents

Abstract

PURPOSE:To paint efficiently with different colors by specifying the angle between two kinds of spray guns with a stripe in-between the viscosity of a paint, the distance, etc., and painting under such conditions. CONSTITUTION:A stripe tape (y) coated with a releasable protective film and having <=20mm width is stuck on a material X to be painted, and different colors are painted on both sides of the tape. In the case, the angle between two kinds, of air spray guns is regulated to 20-45 deg., the viscosity of a paint to 10-15sec FC#4, the distance between a nozzle and the matrix X to be painted to 50-150mm, the paint pressure to 0.3-0.8kg/cm<2>, the air pressure to 2-3kg/cm<2>, the discharge of the paint to 20-100g/min, and the relative velocity between the material X to be painted and a spray gun 5 to 10-15m/sec. The material is painted under such conditions. The protective film is then released from the stripe tape. Consequently, different colors can be painted efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of Application The present invention is directed to the application of different paints on one side and the other side of an object to be painted, such as the body of a passenger car, on which a decorative stripe tape is pasted. How to paint the colors by spraying them with an air spray gun.

Problems to be solved by conventional techniques and inventions, for example,
Decorative stripe tape with the car model name printed on it is pasted on the body of a passenger car, and the upper and lower sides are sometimes painted in different colors. The surface of the stripe tape is covered with a removable protective film, and two spray guns are placed near the conveyance line of the object to be coated, and the upper spray gun is used to spray the upper edge of the stripe tape and the upper coating Spray the paint only on the surface to be painted, and use the lower spray gun to spray the paint only on the lower edge of the stripe tape and the surface to be painted below it, and after the paint dries, peel off the protective film from the stripe tape. However, if the width of the stripe tape is 20 m or less, some of the paint sprayed on the surface to be painted above or below the stripe tape will be bounced off by the air flow that hits the surface to be painted. The paint may scatter and adhere to the other surface to be painted beyond the striped tape, or the paint applied to the upper surface to be painted may flow down the surface of the striped tape and reach the surface to be painted on the lower side. Because it is difficult to avoid paint defects caused by paint problems, conventional methods have been to paint either the upper or lower surface to be painted and allow the paint film to dry, then mask that painted surface 1 and apply paint to the other surface. A method of painting the surface to be painted is generally used, but such a painting method has the disadvantage of a complicated process and high cost.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a method that eliminates such drawbacks and enables efficient color coating on two surfaces separated by a stripe tape.

Example Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. The object to be painted X in this example is as shown in FIG.

It has a flat plate shape and has a removable surface with a letter etc. printed in the center in the vertical direction, and a decorative striped tape y, which costs less than $120 and is covered with a protective film 2, is pasted over the entire width. Then, the lower side to be painted A and the upper side to be painted B of the stripe tape y are painted with different paints.

In Fig. 2, l is a conveyor, and hangers 2 hanging at regular intervals transport a large number of the three objects X to be painted in the direction of the arrow, with the striped tape y facing horizontally. Near the conveyor l, two stands 3 and 4 are installed with an interval in the conveyance direction, and the upper part of the stand 3 on the rear side in the conveyance direction is used to hold the objects to be coated. The first air spray gun 5a, which sprays paint onto the part of the surface A to be painted below X that is in contact with the striped tape y, is in a diagonally downward position. A second air spray gun 5b, which sprays paint onto the portion of the upper surface B to be painted that is in contact with the striped tape y, is mounted in an upward position by an arm 7 bent in an L-shape. The remaining portions of the surfaces A and B to be painted are covered by a third. Painting is performed by fourth air spray guns 6a and 6b.

Each air spray gun 5a, 5b, 6a, 6b has a ring-shaped air nozzle around a paint nozzle that discharges paint at low pressure, and opens and closes a needle valve driven by an air cylinder provided at the rear end. The discharge and stop of the paint is controlled by the system, and the discharged paint is atomized by collision with the pressurized air ejected from the air nozzle, and the air flow spreads in a fan shape to reach the surface to be painted. There it is,
The first and third parts are attached to the stand 3 at the rear in the transport direction.
Air spray guns 5a, 6a paint supply hose 9
a and 10a are pressure control valves 11a, respectively.

paint supply water source 9b for the second and fourth air spray guns 5b, 6b connected to the first paint pump 13a via 12a and mounted on the stand 4 in the forward direction of conveyance;
10b is a second paint pump 1 which pumps a different paint from the first paint pump through pressure control valves 11b and 12b, respectively.
3b, and each air spray gun 5
Air supply hose 1 for paint atomization of a, 5b, 6a, 6b
4 is connected to a pressurized air supply source 17 via a pressure reducing valve 15 and an electromagnetic on-off valve 16, and an air supply hose 18 for controlling the opening and closing of the needle valve is connected to the pressurized air supply source 1 via an electromagnetic on-off valve 19.
7 is connected.

Here, each air spray gun 5a, 5b, 6a, 6b
When considering the painting conditions, the amount of paint discharged per unit area of the surface to be painted is large, and.

If the viscosity of the paint is low, the applied paint will run off, and
If the pressure of the paint atomizing air is high and the distance between the nozzle and the surface to be painted is close, the paint will be bounced off the surface to be painted.As a result of various experiments, we found that it is necessary to perform painting under the following conditions. It turns out that there is something.

Paint viscosity 10-15secFC#4. Distance between nozzle and surface to be painted: 50-150mm, paint spout diameter: 0.3-1.0
-1 Paint atomization air pressure 2-3 kg/cd, paint discharge amount 20-100 g/win, relative speed of the object to be painted with each air spray gun 10-15 m/sin
(In this embodiment, each air spray gun is fixedly installed, so the relative speed is equal to the conveyance speed of the conveyor.) Note that the first and second air spray guns 5a.

5b is the angle with respect to each surface to be painted A and B (the door in Fig. 3).
α) is 20 mm from the adhesive side of the stripe tape y.
It was also confirmed through experiments that when the angle is between 45 degrees and 45 degrees, the repelled paint does not reach the surface to be painted on the other side.

Under these conditions, paint is sprayed onto both the upper and lower painted surfaces A and B, and after the paint dries, the protective film 2 is peeled off from the stripe tape y.

Structure and Effects of the Invention As specifically explained in the above embodiments, the two-color spray coating method of the present invention applies a decorative striped tape having a width of 20IIll or less, one surface of which is coated with a removable protective film. In this method, the first paint and the second paint are applied to the object to be painted and are spray-coated separately on one side and the other side of the stripe tape across the stripe tape. the striped tape is conveyed parallel to the conveying direction, and first and second air sprays are directed respectively to the one side and the other side of the striped tape to be painted along the conveying path. The guns are arranged so that the angle of the center line of the jetted paint stream to the surface to be painted from the stripe tape side is 20° to 45'', and each air spray gun sprays a paint with a viscosity of 10 to 15 secondsFC$4.
．． The distance from the nozzle to the surface to be painted is 50-150 am, the diameter of the paint outlet is 0°3-1.0 mm, and the paint pressure is 0.3-0.
8kg/c+J, air pressure for paint atomization 2-3 kg
/d, paint discharge rate 20-100 g/min, relative speed of the object to be coated with respect to each air spray gun lO~1
The gist of this method is to spray paint at a rate of 5m/win to coat each of the surfaces to be painted, and then peel off the protective film from the stripe tape, even if the width of the stripe tape is narrow. To achieve the effect that one side and the other side can be coated with different paints continuously and efficiently without causing color mixing.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an object to be painted, FIG. 2 is a perspective view of a painting line according to an embodiment of the present invention, and FIG. 3 is a sectional view of the painted state. l: Conveyor 5a: First air spray gun 5b
=Second air spray gun 13a, 13b: Paint pump 17: Pressurized air supply source X: Object to be painted y Varnish drive tape 2: Protective film A, B: Surface to be painted

Claims (1)

[Claims] Decorative width 2 whose surface is covered with a removable protective film
A method in which a stripe tape with a thickness of 0 mm or less is attached to an object to be painted, and a first paint and a second paint are spray-painted separately on one side and the other side of the stripe tape. The object to be coated is transported along a transport path so that the striped tape is parallel to the transport direction, and along the transport path, the coating surfaces on the one side and the other side of the stripe tape are oriented separately. The first and second air spray guns are arranged so that the angle of the center line of the sprayed paint flow to the surface to be painted from the stripe tape side is 20° to 45°, and the paint is sprayed from each air spray gun. Viscosity 1
0-15secFC#4, distance from nozzle to surface to be painted 50-150mm, paint spout diameter 0.3-1.0mm
, paint pressure 0.3-0.8 kg/cm^2, paint atomization air pressure 2-3 kg/cm^2, paint discharge amount 20-1
After spraying the paint at a relative speed of 10 to 15 m/min with respect to each air spray gun of the object to be painted and painting each of the surfaces to be painted, peeling off the protective film from the stripe tape. A two-color spray painting method featuring