JP2002079174A - Two-tone coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain the improvement of reliability and the reduction of coating cost by making the finishing of the border line clear and decreasing the number of coating processes. SOLUTION: An A-colored coating film surface PA is formed on a body 12 by applying an A-colored coating material in an A-colored area coating process. In a boundary area coating process, a rotary spray head type coater 31 is arranged to be inclined to the body 12 toward the boundary area, a B- colored coating material is sprayed toward the body 12 only with the centrifugal force to form a boundary coating film surface PB1. Next, in a belt-like area coating process, the rotary spray head type coater is arranged to be inclined to face the belt-like area to form a belt-like coating film surface adjacent to the boundary coating film surface PB1 and in a remaining area coating process, an underside coating film surface adjacent to the belt-like coating film surface is formed. As a result, a definite border line BL is formed since the B-colored coating material is deposited on the surface of the body 12 without rebounding when the boundary coating surface area PB1 is coated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-tone coating method for coating an object such as an automobile body in two colors.

[0002]

2. Description of the Related Art In general, a coating apparatus for coating an object to be coated is provided with a coating work machine such as a coating robot provided in a coating booth and a coating work machine which is attached to the coating work machine and atomizes the paint to form a coating object. And a coating machine that sprays the water. When painting an object to be coated such as a car body, when the body is conveyed to the painting booth by the carrier device, the painting machine attaches the painting machine attached to the tip of the arm of the painting robot to the body. The coating is performed by spraying a paint toward the body while keeping a certain distance from the paint surface according to the shape of the paint surface.

[0003] Here, in addition to the case of applying a single-color coating to the body of an automobile, a so-called two-tone coating, for example, in which the upper half and the lower half of the body are coated with different colors, is known. Have been.

That is, according to the conventional two-tone coating method, as shown in FIG. 35, an upper half of a body is coated with a first color paint A color paint (step 1), and this A color is applied (step 1). A paint is applied on the coating surface using a clear paint (step 2), and the body is placed in a baking furnace to bake the paint on the body (step 3). Next, a masking tape is attached to the position of the boundary of the paint color, and the surface of the A-color coating film is covered with masking paper (step 4).
The second color paint is prevented from adhering to the color coating surface. When the masking operation is completed, the lower half of the body is coated with the B color paint so that the upper part thereof overlaps the A color coating surface (step 5),
Painting is performed using a clear paint (step 6). next,
These paints are baked again in a baking oven (step 7),
By peeling off the masking tape (step 8),
The body can be painted in two colors (two-tone) at the position of the boundary line.

However, in this two-tone coating, the surface of the B-color coating film is forcibly peeled off along with the boundary line together with the masking tape. Therefore, the position of the border line
A step is formed between the A-color coating surface and the B-color coating surface. Further, fine irregularities such as saw blades are continuously formed in the length direction on the boundary of the B-color coating surface separated by the masking tape. These are factors that impair the quality of the finish coating.

[0006] The masking operation consists of attaching and detaching a masking tape and masking paper.
It is difficult to automate these masking operations, and at present, workers manually perform the masking operations, which is a factor that reduces productivity.

Further, in the two-tone coating method using a masking tape or the like, in order to attach the masking tape to the A-color coated surface and the clear coated surface, the A-color coated surface is baked and dried and cured. Need to be kept. For this reason,
Work such as painting of paint, painting of clear paint, and baking of paint must be performed separately for each of the A color and the B color, resulting in a problem that productivity is reduced and coating cost is increased.

Therefore, there is a two-tone coating method in which the above-described masking operation with a masking tape or the like is omitted to improve the productivity. A conventional coating method of this kind is disclosed, for example, in Japanese Patent Application Laid-Open No. 58-58168. And Japanese Patent Application Laid-Open No. 11-57606.

First, a coating method described in Japanese Patent Application Laid-Open No. 58-58168 (hereinafter referred to as a first prior art) performs heavy rust prevention coating, and comprises a coating machine and a masking plate at the tip of a robot arm. And a masking device.
And this painting method, when performing heavy rust prevention painting,
The upper end of the masking plate is covered by contacting the tip of the masking plate with the body of the vehicle at the boundary. In this state, the sprayer sprays heavy rust preventive paint to paint only the lower part of the body.

The two-tone coating method described in Japanese Patent Application Laid-Open No. 11-57606 (hereinafter, referred to as a second prior art) employs a coating method for forming a boundary line on an object 101 as shown in FIG. Is used, a two-fluid nozzle coating gun 102 (so-called airbrush gun) having good straightness of the paint, that is, having a spray pattern opening angle θ of 30 degrees or less is used. Also, above the coating gun 102,
An air gun (not shown) is provided, and air is ejected from the air gun toward a boundary line. Then, in the coating method according to the first prior art, the coating gun 102 is sprayed on the object to be coated 101 at least half the spray pattern opening angle θ (θ
(/ 2 or more), the boundary is formed by spraying the paint from the coating gun 102 toward the work 101 in this state. At the time of this coating, air is sprayed from the air gun toward the boundary line to prevent, for example, the B color paint sprayed from the coating gun 102 from adhering to the previously coated A color coating surface.

[0011]

In the first prior art coating method disclosed in Japanese Patent Application Laid-Open No. 58-58168, a masking plate is used to cover a part other than a part to be coated. Therefore, when painting is performed, a large amount of paint adheres to the masking plate. For this reason, a paint scraping device for scraping the paint adhered to the masking plate is separately required, and the equipment becomes complicated and large. In addition, since the masking plate has its tip in contact with the body, there is a possibility that other painted surfaces may be damaged. For this reason, the coating method according to the first prior art can be used for undercoating which does not necessarily require a high quality finish such as heavy rust prevention coating, but cannot be used for finish coating.

A second prior art coating method disclosed in Japanese Patent Application Laid-Open No. 11-57606 uses a two-fluid nozzle coating gun 102 (air brush gun) as a coating machine for forming a boundary line. The gun 102 discharges the paint by the pressure of the spray air. Accordingly, the coating gun 102 is blasting the spray air with the paint. For this reason, since the spray air and the paint particles bounce off the surface of the article 101 to be scattered, when the border paint is formed by the B paint, the B paint becomes A
There is a problem that it adheres to the color coating surface.

In the coating method according to the second prior art, air is supplied to the position of the boundary using an air gun. However, the air gun cannot supply air to a desired position due to variations in the direction in which the air is ejected, and disperses the paint sprayed from the coating gun 102 toward the boundary line to disturb the boundary line. There is a problem of doing it.

Further, the two-fluid nozzle coating gun 102 includes:
It is generally used to spray paint on paintings, posters, and other arts and crafts, and is used like a paintbrush. Further, the two-fluid nozzle coating gun 102 sprays a low-viscosity dye or a lacquer-based paint with a small discharge amount, and has a low ability to atomize a paint used for an automobile body. Accordingly, the two-fluid nozzle coating gun 102 is suitable for drawing fine lines with a small spray pattern, but is not suitable for coating a vehicle body over a wide area, and thus requires a large amount of coating time. On top of that, you cannot expect a high quality paint finish.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to clarify the finish of a boundary line and reduce the number of coating steps, thereby improving reliability and reducing coating cost. It is an object of the present invention to provide a two-tone coating method capable of achieving reduction.

[0016]

Means for Solving the Problems In order to solve the above-mentioned problems, a two-tone coating method adopted by the invention according to claim 1 is a method for coating [A]. The first color area coating process to be performed and [B]. (1). The rotary atomizing head of the rotary atomizing head type coating machine is directed toward the boundary area with respect to the object at a position close to the object. (2) Supplying mist suppression air for suppressing the paint mist composed of the second color paint from scattering on the surface of the first color coating film in front of the rotary atomizing head; (3) spraying No shaping air for shaping the pattern is supplied. (4). With no high voltage applied or only low voltage high voltage applied, (5).
A boundary area painting step for forming a boundary line with the color coating surface, [C]. (1). The rotary atomizing head is directed toward the band-like area with respect to the object at a position close to the object. Tilt and place,
(2) Supply mist suppression air for preventing the paint mist composed of the second color paint from scattering on the surface of the first color coating, in front of the rotary atomizing head, and (3) without applying a high voltage. Or, in a state where only a low voltage high voltage is applied, (4). While the rotary atomizing head is reciprocated, a belt-like coating is applied to the surface of the object to be coated following the boundary coating surface using the second color coating. And a band-shaped area painting process.

[0017] With this configuration, in the first color area coating step, the surface of the object is coated with the first color coating by applying the first color paint to the surface of the object. Can be formed.

Next, in the boundary area painting step, the rotary atomizing head is arranged at a position close to the object to be coated and inclined toward the boundary area with respect to the object to be coated. Is supplied in front of the rotary atomizing head to prevent mist from being scattered on the surface of the first color coating film, while shaping air for shaping the spray pattern is not supplied, and no high voltage is applied or low pressure is applied. With only a high voltage applied, the rotary atomizing head is rotated at high speed to spray the second color paint.

Accordingly, the second color paint flies radially outward by centrifugal force while being pulled by the negative pressure region formed in front of the rotary atomizing head when the rotary atomizing head is rotated at high speed. I do. In this case, since the rotary atomizing head is arranged close to the object to be coated, the second color paint is applied to the object to be coated with little scattering before atomization due to air resistance. A simple boundary line can be formed. Also, since the rotary atomizing head is inclined with respect to the object to be coated, the second color paint is sprayed only by centrifugal force without using spray air or the like,
These spray particles are applied to the surface of the object without rebounding and scattering. Further, the mist suppressing air supplied in front of the rotary atomizing head suppresses the paint mist composed of the second color paint from scattering on the surface of the first color paint film, thereby improving the paint finish.

Next, in the band-shaped area coating step, the rotary atomizing head is disposed at a position close to the object to be coated and inclined toward the band-shaped area with respect to the object to be coated. Is supplied to the front of the rotary atomizing head to prevent mist from being scattered on the surface of the first color coating film, and without applying a high voltage or applying only a low-voltage high voltage, A wide band-like (belt-like) coating is applied to the surface of the object following the boundary line using the second color paint while the head is reciprocating.

In this manner, the second color paint is continuously applied to the boundary coating surface in a state in which scattering to the first color coating surface is suppressed, in substantially the same manner as the coating operation in the boundary area coating process described above. Is done. At this time, since the rotary atomizing head type coating machine is reciprocated, it is possible to apply the second color paint to a wide surface of the object to be coated following the boundary coating surface.

Further, the two-tone coating method adopted by the invention of claim 2 is a method of [A], a first color area coating step of coating the surface of an object to be coated with a first color coating, and [B]. (1) A rotary atomizing head of a rotary atomizing head type coating machine is disposed at a position close to an object to be coated and inclined toward a boundary area with respect to the object to be coated,
(2) Supplying mist suppression air for preventing the paint mist composed of the second color paint from scattering on the first color coating surface in front of the rotary atomizing head, and (3) shaping to shape the spray pattern. Air is not supplied. (4). With no high voltage applied or with only low voltage applied at high voltage, (5). Forming a boundary area coating step, [C]. (1). A rotary atomizing head is arranged at a position close to the object to be inclined toward the belt-shaped area with respect to the object to be coated, and (2). Supply mist suppression air for preventing paint mist composed of the second color paint from scattering on the surface of the first color paint film in front of the rotary atomizing head, and (3) applying no high voltage or low pressure. In the state where only a high voltage is applied, (4). While the rotary atomizing head is reciprocating, a band-shaped coating is applied to the surface of the object following the boundary coating surface using the second color coating. A strip area coating stage, consisting of [D]. The surface of the strip areas remaining coated article which has not been coated by the coating process, the remainder area coating stage for performing coating using a second color coating.

With this configuration, in the first color area coating step, the surface of the object is coated with the first color coating by applying the first color paint to the surface of the object. Can be formed.

Next, in the boundary area coating step, the rotary atomizing head is disposed at a position close to the object to be coated and inclined toward the boundary area with respect to the object to be coated, and a paint mist made of the second color paint is applied. Is supplied in front of the rotary atomizing head to prevent mist from being scattered on the surface of the first color coating film, while shaping air for shaping the spray pattern is not supplied, and no high voltage is applied or low pressure is applied. With only a high voltage applied, the rotary atomizing head is rotated at high speed to spray the second color paint.

Thus, the second color paint flies radially outward by centrifugal force while being pulled by the negative pressure region formed in front of the rotary atomizing head when the rotary atomizing head is rotated at high speed. I do. In this case, since the rotary atomizing head is arranged close to the object to be coated, the second color paint is applied to the object to be coated with little scattering before atomization due to air resistance. A simple boundary line can be formed. Also, since the rotary atomizing head is inclined with respect to the object to be coated, the second color paint is sprayed only by centrifugal force without using spray air or the like,
These spray particles are applied to the surface of the object without rebounding and scattering. Further, the mist suppressing air supplied in front of the rotary atomizing head suppresses the paint mist composed of the second color paint from scattering on the surface of the first color paint film, thereby improving the paint finish.

Next, in the band-shaped area coating step, the rotary atomizing head is arranged at a position close to the object to be coated and inclined toward the band-shaped area with respect to the object to be coated. Is supplied to the front of the rotary atomizing head to prevent mist from being scattered on the surface of the first color coating film, and without applying a high voltage or applying only a low-voltage high voltage, The surface of the object following the boundary line is painted with the second color paint while the head is reciprocated.

In this manner, the second color paint is continuously applied to the boundary coating surface in a state where scattering to the first color coating surface is suppressed, in substantially the same manner as the coating operation in the boundary area coating process described above. Is done. Further, in the band-shaped area coating step, a wide band-shaped (belt-shaped) coating is applied by the reciprocating operation of the rotary atomizing head. Therefore, when the second color coating is applied in the remaining area coating step, the first color coating is applied. Increase the distance to the membrane surface,
It is possible to prevent particles of the color paint from adhering to the surface of the first color coating film.

Next, in the remaining area coating step, the surface of the object to be coated following the belt-shaped coating film surface is coated with the second color coating material. At this time, since the boundary coating surface composed of the second color coating and the band-shaped coating surface are interposed between the coating portion in the remaining area coating process and the first color coating surface, the normal coating operation is performed by the coating machine. In this case, the particles of the second color paint can be prevented from scattering on the surface of the first color coating film.

According to the third aspect of the present invention, in the boundary area coating step, (1) the position between the edge of the rotary atomizing head and the object to be coated at the position where the boundary line with the first color coating surface is coated; (2) With a reciprocating trajectory that increases the coating distance between the edge of the rotary atomizing head and the workpiece as the distance from the boundary with the first color coating surface increases. (3) The painting is performed while moving the rotary atomizing head in a direction crossing the boundary line.

Thus, when the rotary atomizing head is reciprocated to perform coating, the edge of the rotary atomizing head is close to the object to be coated at the position of the boundary with the surface of the first color coating film. Therefore, a boundary line composed of a thick and clear coating film surface can be formed at the position of this boundary line. On the other hand, at the position away from the boundary with the first color coating film surface, the edge of the rotary atomization head is separated from the object to be coated, so that the spray particles are applied to a wider range than the position of the boundary. . Thereby, a flat coating film surface can be formed at a position away from the boundary line.

According to the fourth aspect of the present invention, in the boundary area coating step, the coating is performed while the rotary atomizing head is moved substantially parallel to the boundary line.

As a result, the surface of the object to be coated is made smooth (linear) by the rotary atomizing head moving substantially parallel to the boundary line.
A simple boundary line can be formed.

According to the fifth aspect of the present invention, in the belt-shaped area coating step, (1) the coating distance between the edge of the rotary atomizing head and the object to be coated on the boundary coating surface side is minimized, 2) With a reciprocating trajectory that increases the coating distance between the edge of the rotary atomizing head and the workpiece as the distance from the boundary coating surface increases, (3).
This is because the painting was performed while moving the rotary atomizing head in the direction crossing the boundary.

Accordingly, at the position on the boundary coating film surface side, the coating distance between the edge of the rotary atomizing head and the object to be coated is minimized to suppress the scattering of the coating, so that the second color coating can be prevented. Particles can be prevented from adhering to the first color coating surface beyond the boundary coating surface. In the case of applying the second color coating subsequent to the band-shaped coating surface, a portion where the second color coating overlaps, that is, a position away from the boundary line, can be formed as a flat coating surface.

According to a sixth aspect of the present invention, in the belt-shaped area coating step, the coating is performed while reciprocating the rotary atomizing head substantially parallel to the boundary line.

Thus, the second color paint sprayed from the rotary atomizing head is applied almost parallel to the boundary line.
It is possible to prevent the particles of the color paint from scattering over the boundary coating surface and the band-like coating surface and onto the first color coating surface.

According to the seventh aspect of the invention, the shaping air is not used or a small amount of shaping air that does not resist the mist suppression air is used in the band-shaped area coating step.

As a result, the second color paint sprayed by the centrifugal force from the rotary atomizing head is applied to the object without being disturbed by the shaping air, so that the particles of the second color paint are scattered. Adhesion to the first color coating film surface can be prevented.

According to the invention of claim 8, the rotary atomizing head type coating machine is provided with an air nozzle for discharging mist suppression air forward of the rotary atomizing head. The mist suppressing air is supplied from the air nozzle to the front of the rotary atomizing head.

Thus, when the mist suppression air is supplied from the air nozzle to the front of the rotary atomizing head, the mist suppression air causes the paint mist of the second color paint to pass over the boundary line to the first color coating surface. Spattering can be prevented.

According to the ninth aspect of the present invention, in the rotary atomizing head type coating machine, an air nozzle for discharging mist suppressing air toward the rotary atomizing head, and a mist suppressing air discharged from the air nozzle is rotary atomized. A rectifying plate leading to the front of the head is provided, and in the boundary area painting step and the band-shaped area painting step, mist suppressing air is discharged from the air nozzle, and the mist suppressing air is supplied to the front of the rotary atomizing head by the rectifying plate. is there.

Thus, when the mist suppressing air is supplied from the air nozzle toward the rotary atomizing head, the mist suppressing air can change its direction toward the rotary atomizing head by hitting the rectifying plate, and is controlled by the rectifying plate. The mist suppression air can prevent the paint mist of the second color paint from scattering over the boundary line toward the first color coating surface.

According to the tenth aspect of the present invention, in the boundary area coating step and the belt-shaped area coating step, the rotary atomizing head is inclined by 50 to 80 degrees with respect to a line perpendicular to the surface of the object to be coated. .

Thus, the paint particles discharged by the centrifugal force of the rotary atomizing head can be applied to the surface of the object without being scattered to the first color coating surface.

Further, the two-tone coating method adopted by the invention of claim 11 is a method of [A], a first color area coating step of coating the surface of an object to be coated with a first color coating, and [B]. (1) The rotary atomizing head of the rotary atomizing head type coating machine is arranged at a position close to the object to be inclined toward the band-shaped boundary area with respect to the object, and (2) the second color. (3) Supply shaping air for shaping the spray pattern without supplying mist suppression air for suppressing the paint mist made of paint from scattering on the first color coating film surface, and (3). 4). With no high voltage applied or only a low voltage high voltage applied, (5) applying a band-shaped coating using a second color paint while reciprocating the rotary atomizing head to form a first color. A band-shaped boundary area coating step for forming a boundary line with the coating film surface; [C]. The surface of the coating material, the second
And a rest area painting step of painting with a color paint.

According to this structure, in the first color area coating step, the surface of the object is coated with the first color coating by applying the first color paint to the surface of the object. Can be formed.

Next, in the band-shaped boundary area coating step, the rotary atomizing head is disposed at a position close to the object to be coated and is inclined toward the band-shaped boundary area with respect to the object to be coated, and is made of the second color paint. A mist suppression air for preventing the paint mist from being scattered on the surface of the first color coating film is supplied in front of the rotary atomizing head, while a shaping air for shaping the spray pattern is not supplied, and a high voltage is not applied or With only low voltage and high voltage applied,
The second color paint is sprayed by rotating the rotary atomizing head at high speed while reciprocating the rotary atomizing head.

Accordingly, the second color paint flies radially outward by centrifugal force while being pulled by the negative pressure area formed in front of the rotary atomizing head when the rotary atomizing head is rotated at high speed. I do. In this case, since the rotary atomizing head is arranged close to the object to be coated, the second color paint is applied to the object to be coated with little scattering before atomization due to air resistance. A simple boundary line can be formed. Also, since the rotary atomizing head is inclined with respect to the object to be coated, the second color paint is sprayed only by centrifugal force without using spray air or the like,
These spray particles are applied to the surface of the object without rebounding and scattering. Further, the mist suppressing air supplied in front of the rotary atomizing head suppresses the paint mist composed of the second color paint from scattering on the surface of the first color paint film, thereby improving the paint finish.

Next, in the remaining area coating step, the surface of the object to be coated following the band-shaped boundary coating film surface is coated with the second color paint. At this time, since a wide band-shaped boundary coating surface made of the second color paint is interposed between the coating portion in the remaining area coating process and the first color coating surface, normal coating work is performed by a coating machine. Even in this case, it is possible to prevent the particles of the second color paint from scattering on the surface of the first color coating film.

According to the twelfth aspect of the invention, in the step of coating the band-shaped boundary area, (1) the edge of the rotary atomizing head and the object to be coated are coated at the position where the boundary line with the first color coating surface is coated. (2). The reciprocating trajectory that increases the coating distance between the edge of the rotary atomizing head and the workpiece as the distance from the boundary with the first color coating surface increases. (3). The spraying is performed while moving the rotary atomizing head in a direction crossing the boundary line.

When the rotary atomizing head is reciprocated to perform coating, the rotary atomizing head is close to the object to be coated at the position of the boundary with the surface of the first color coating film. A boundary line composed of a thick and clear coating surface can be formed at the position of the boundary line. On the other hand, at a position away from the boundary with the first color coating surface, the rotary atomizing head is separated from the object to be coated, so that the spray particles are applied to a wider area than at the position of the boundary. Thereby, a flat coating film surface can be formed at a position away from the boundary line.

According to the thirteenth aspect of the present invention, in the strip-shaped boundary area coating step, the coating is performed while moving the rotary atomizing head substantially parallel to the boundary line.

As a result, the surface of the object to be coated is made smooth (linear) by the rotary atomizing head moving substantially parallel to the boundary line.
A simple boundary line can be formed.

According to a fourteenth aspect of the present invention, the rotary atomizing head type coating machine is provided with an air nozzle for discharging mist suppressing air toward the front of the rotary atomizing head. That is, mist suppression air was supplied in front of the atomizing head.

According to the fifteenth aspect of the present invention, the rotary atomizing head type coating machine includes an air nozzle for discharging mist suppressing air toward the rotary atomizing head, and a mist suppressing air discharged from the air nozzle. A straightening plate that guides forward of the head is provided,
In the band-shaped boundary area coating step, mist suppression air is discharged from the air nozzle, and the mist suppression air is supplied to the front of the rotary atomizing head by the rectifying plate.

According to a sixteenth aspect of the present invention, in the strip-shaped boundary area coating step, the rotary atomizing head is inclined by 50 to 80 degrees with respect to a line perpendicular to the surface of the object to be coated.

Thus, the coating particles discharged by the centrifugal force of the rotary atomizing head can be applied to the surface of the object without being scattered to the first color coating surface.

According to the seventeenth aspect of the present invention, a paint baking step for simultaneously baking the first color paint and the second color paint applied in each coating step is performed after the completion of each coating step.

Thus, after the first color paint is applied,
The coating operation can be performed by a so-called wet-on-wet method, in which the second color paint is applied in a wet state before the coating surface of the first color paint is baked and dried and hardened. For this reason, the paint baking step after the first color area painting step, which was required when performing the masking operation in the prior art, can be omitted, and the operation process can be simplified.

[0060]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a two-tone coating method according to an embodiment of the present invention;

First, FIG. 1 to FIG. 23 show a first embodiment of the present invention. First, the configuration of a two-tone coating device used for two-tone coating will be described.

Reference numeral 1 denotes a painting factory. In the painting factory 1, a two-color (two-tone) coating of an A-color paint as a first-color paint and a B-color paint as a second-color paint is applied to an automobile body 12 described later. ing. In the coating factory 1, an A color area coating stage 2, a boundary area coating stage 3, a belt-shaped area coating stage 4, a remaining area coating stage 5, a clear coating stage 6, a paint A baking stage 7 is provided.

In the first A-color area painting stage 2, the upper half of the body 12, ie, the hood 12A and the roof 1
The whole surface of 2B, the left front door 12C, the left rear door 12D, the right front door, the right rear door (not shown), the upper half of the back door 12E, and the like are coated with the A color paint. .

Here, a description will be given of only the left side rear door 12D shown in FIG. 17, and the A color area painting stage 2 paints the A color area a using the A color paint. In the next boundary area painting stage 3, as shown in FIG. 18, a B color paint different from the A color paint is applied so as to overlap the lower part of the A color coating surface PA painted in the A color area painting stage 2. A boundary line BL is formed by applying a coating extending in the front and rear directions to the boundary area b. In the next zonal area painting stage 4,
As shown in FIG. 22, B is located at the lower position of the body 12 following the boundary coating surface PB1 painted on the boundary area painting stage 3.
Wide band (belt) in band area c using color paint
Paint. In the next remaining area painting stage 5, as shown in FIG. 23, of the surfaces of the body 12, the remaining surfaces not painted by the A color area painting stage 2, the boundary area painting stage 3, and the belt-shaped area painting stage 4, That is, the lower area d located below the belt-like coating surface PB2 is coated with a B color paint, and the lower coating surface PB3
To form

The next clear coating stage 6 is to apply a clear coating on the coating surface coated in the A color area coating stage 2, the boundary area coating stage 3, the belt-shaped area coating stage 4, and the remaining area coating stage 5. Is applied. And the final paint baking stage 7 is
The A color paint, the B color paint, and the clear paint applied to the body 12 after passing through # 6 are simultaneously baked on the body 12 in a baking furnace (not shown).

Here, the A color area painting stage 2, the boundary area painting stage 3, the band-shaped area painting stage 4, the remaining area painting stage 5, and the clear painting stage 6
The tracking devices 13 and 14 described later, the coating robots 15 and 16 and the rotary atomizing head type coating machines 21 and 31 shown in FIG.
41 and 51 are provided.

The body 12 to be described later is mounted on each stage 2.
3, the upper half of the body 12 becomes the A-color coating surface PA and the lower half becomes B, as shown in the left rear door 12D shown in FIG. The two-tone coating that has become the color coating surface PB is applied.

On the other hand, reference numerals 11 and 11 denote a pair of conveyors (see FIG. 2) provided in the coating factory 1. Each of the conveyors 11 includes an A-color area painting stage 2, a boundary area painting stage 3, a belt-shaped area painting. The stage 4, the remaining area painting stage 5, and the clear painting stage 6 are arranged. The transport conveyor 11 is provided with a body 12 described later.
Is supported, and the body 12 supported by the support 11A is transported continuously or intermittently in the coating factory 1.

Reference numeral 12 denotes an automobile body as an object mounted on the support base 11A of the conveyor 11; the body 12 includes a hood 12A, a roof 12B, a left front door 12C, a left rear door 12D, It is roughly constituted by a right front door, a right rear door (both not shown), a back door 12E and the like.

Reference numeral 13 denotes a tracking device disposed on the left side of the conveying direction by the conveyor 11 and disposed on the A-color area painting stage 2. Reference numeral 14 denotes a tracking unit located on the right side of the conveying direction by the conveyor 11 and an A-color area painting stage. 2 shows a tracking device arranged in FIG. Here, the tracking devices 13 and 14 are roughly constituted by tracking rails 13A and 14A extending in parallel with the conveyor 11 and moving tables 13B and 14B movably provided along the tracking rails 13A and 14A. The moving table 1
3B and 14B are mounted with painting robots 15 and 16 to be described later. Then, the tracking devices 13 and 14
Is for moving the coating robots 15, 16 in the forward or reverse direction with respect to the body 12 transported by the transport conveyor 11.

Reference numeral 15 denotes a movable platform 13 of the tracking device 13
B, a painting robot on the left side, wherein the painting robot 15 comprises a swivel 15A rotatably provided on the moving table 13B, and a vertical arm swingably provided on the swivel 15A. 15B and a horizontal arm 15C rotatably attached to the upper end of the vertical arm 15B.
5D is attached.

Reference numeral 16 denotes a right-hand painting robot mounted on a moving table 14B of the tracking device 14. The painting robot 16 includes a swivel (not shown), It is roughly constituted by a vertical arm 16B, a horizontal arm 16C, and a wrist (not shown).

A tracking device and a painting robot (both not shown) similar to those described above are also provided on the boundary area painting stage 3, the band-shaped area painting stage 4, the remaining area painting stage 5, and the clear painting stage 6. Have been.

Further, in each of the coating stages 2 to 6,
Because of different coating methods, a plurality of types of rotary atomizing head type coating machines 21, 31, 41, and 51 described later are selectively used. These coating machines 21, 31, 41, 51 differ according to the coating conditions. Specifically, for example, the tilt angle with respect to the body 12, the body 12 and the rotary atomizing head 23,
Edges 23A, 33A, 43A, 53 of 33, 43, 53
A with coating distance, with or without shaping air, with or without mist suppression air, high voltage applied state (with or without applied
No, high voltage magnitude).

The rotary atomizing head type coating machine 21 used in the A color area coating stage 2 will be described. As shown in FIG. 4, the coating machine 21 has a cylindrical casing 22 whose base end is attached to the wrist 15D and whose intermediate position is bent in a V-shape, and is rotatably disposed at the distal end of the casing 22. The rotary atomizing head 23 is included.
The rotary atomizing head 23 is attached to a rotating shaft of an air motor (not shown) built in the casing 22, and is rotated at a high speed by the air motor. In the casing 22, a feed tube (not shown) whose base end is connected to the paint supply source and whose front end extends in the rotary shaft of the air motor and opens toward the rotary atomizing head 23 is provided. The feed tube supplies paint to the rotary atomizing head 23.

Further, a number of shaping air ejection holes (not shown) for ejecting shaping air for shaping the spray pattern of the paint sprayed from the rotary atomizing head 23 are rotated at the tip end side of the casing 22. It is formed so as to surround the atomizing head 23. Further, the coating machine 21 can apply a high voltage to the paint supplied to the rotary atomizing head 23 via the feed tube.
By applying a high voltage of 20 kV, paint can be efficiently applied to the body 12 connected to the ground.

Here, in the rotary atomizing head type coating machine 21 used in the A color area coating stage 2, the rotation center line OO of the rotary atomizing head 23 is substantially perpendicular to the surface of the body 12 (inclination angle). α1 = 0 degree), and the body 12
The A color paint is sprayed while moving according to the surface shape of the A, and the A color coating surface PA is applied to the body 12. At this time,
As shown in FIGS. 4 and 15, the coating distance L1 between the surface of the body 12 and the edge 23A of the rotary atomizing head 23 is 200
mm to 350 mm, and the paint is -30 to
A high voltage of -120 kV is applied. Further, the shaping air ejection holes supply shaping air to the paint sprayed from the rotary atomizing head 23 to shape the spray pattern of the paint. The rotary atomizing head type coating machine 21 used in the A color area coating stage 2 is not provided with an air nozzle for spraying mist suppression air in front of the rotary atomizing head 23 and a rectifying plate.

Next, the rotary atomizing head type coating machine 31 used in the boundary area coating stage 3 disposed downstream of the A color area coating stage 2 will be described with reference to FIG. This coating machine 31 is disposed at a tip end of the casing 32 and a cylindrical casing 32 bent in a V-shape almost in the same manner as the rotary atomizing head type coating machine 21 of the A-color area coating stage 2. The rotary atomizing head 33 is included. Further, the coating machine 31 includes an air motor, a feed tube, and the like (not shown), and can apply a high voltage to the coating material.

However, the coating machine 31 used in the boundary area coating stage 3 has a stay 3 extending from the casing 32.
An air nozzle 35 is provided at the tip end of
2 is different from the coating machine 21 of the A-color area coating stage 2 in that a rectifying plate 36 is provided on the tip side. Then, as shown in FIG.
A plurality of ejection holes 35A, 3 opening toward the front end of
.. Are provided in a line. In addition, like the air nozzle 35 'shown in FIG.
A 'may be provided. And the air nozzle 3
5 supplies the mist suppression air from each ejection hole 35A toward the front of the rotary atomizing head 33, thereby rotating the rotary atomizing head 33.
This prevents the paint particles of the B color paint sprayed from above from scattering and adhering to the A color coating surface PA coated on the A color area coating stage 2.

Further, reference numeral 36 denotes a rectifying plate provided on the tip end side of the casing 22.
The mist suppression air supplied from the nozzle is caused to flow along the surface, whereby the direction of the mist suppression air can be changed to the center side of the coating machine 31, that is, in front of the rotary atomizing head 33,
It is possible to effectively prevent the mist (paint particles) of the color paint from scattering on the A-color coating film surface PA side.

Then, the rotary atomizing head type coating machine 31 of the boundary area coating stage 3 rotates the rotary center line O of the rotary atomizing head 33.
−O is tilted so that the rotary atomizing head 33 faces downward (toward the boundary area b) with respect to a line perpendicular to the surface of the body 12;
At this time, the inclination angle α2 is set in a range of 50 to 80 degrees, for example, about 70 degrees. Also, at this time,
As shown in FIGS. 5 and 15, the coating distance L2 between the surface of the body 12 and the edge 33A of the rotary atomizing head 33 is in the range of 5 mm to 20 mm at the position where the boundary line BL is coated, for example, about 10 mm. At the position indicated by the two-dot chain line spaced downward from the boundary line BL, the coating distance L2 'is larger than the coating distance L2. In addition, the air nozzle 35
Supplies mist suppression air toward the front of the rotary atomizing head 33. In the boundary area coating stage 3, no shaping air is used, and no high voltage is applied, or even if a high voltage is applied, the value is suppressed to a low value of about -10 kV.

Here, the advantage obtained by arranging the rotary atomizing head 33 downward toward the boundary area b and disposing the body 12 and the rotary atomizing head 33 close to each other will be described with reference to FIGS. This will be described using an example.

First, when the rotary atomizing head 33 rotates at a high speed,
In the area around the rotary atomizing head 33, a strong airflow is generated radially outward of the rotary atomizing head 33. As a result, a negative pressure region 37 is formed in front of the rotary atomizing head 33. For this reason, as shown in FIG.
The paint particles ejected from the head try to fly radially outward of the rotary atomizing head 33 due to the centrifugal force generated by the high-speed rotation of the rotary atomizing head 33. However, the ejected paint particles are drawn into the negative pressure area 37 side, and once converge at a position about 10 mm away from the end edge 33A of the rotary atomizing head 33, and then radially outward again due to centrifugal force, air resistance, and the like. Spread and spread.

Therefore, as shown in FIG.
3 is disposed substantially at right angles to the surface of the body 12, and the B color paint is sprayed from the rotary atomizing head 33 with the edge 33 A of the rotary atomizing head 33 approaching the body 12 by about 10 mm. . In this case, as shown in FIGS. 9 and 10, the B-color paint is applied to the body 12 as a B-color coating surface PB 'having an extremely hollow pattern with an outer peripheral side having a thick film. For this reason, when the coating machine 31 is moved with respect to the body 12, as shown in FIG.
L 'can be formed, but this boundary coating surface P
In B1 ', the thickness of the coating film is increased only at the upper and lower ends. Therefore, when the coating is applied successively to the boundary coating surface PB1 ', a uniform film thickness distribution is not obtained, and a good coating finish cannot be obtained.

On the other hand, in the present embodiment, as shown in FIG. 12, the coating machine 31 is tilted downward by about 70 degrees (tilt angle α 2 = 70 degrees), and the edge 33 A of the rotary atomizing head 33 is attached to the body. 12 (approximately 10 mm) (coating distance L2 = 10 mm). As a result, most of the paint particles sprayed from the portion near the body 12 in the edge 33A of the rotary atomizing head 33 are applied to the body 12, so that the position of the boundary line BL of the boundary paint film surface PB1 is changed. Is formed in a thick film, and a clear boundary line BL can be formed. On the other hand, at a position apart from the boundary line BL of the boundary coating surface PB1, the coating distance L2 'is larger than the coating distance L2.
At a position away from the boundary line BL, the paint particles can be sprayed over a wide area to form a thin coating film (blurred state). Thereby, the boundary coating film surface PB separated from the boundary line BL
In the case where a belt-like coating surface PB2 described later is continuously formed below 1, the coating film at the overlapping portion between the boundary coating surface PB1 and the belt-like coating surface PB2 can be prevented from becoming thick, and the film thickness can be prevented. And uniform coating can be achieved.

Also, by setting the coating distance L2 between the edge 33A of the rotary atomizing head 33 and the body 12 to 10 mm, at which the paint particles converge and the scattering is minimized, the centrifugation by the rotary atomizing head 33 is performed. The B-color paint discharged only by force can be sprayed on the surface of the body 12. Accordingly, the paint particles of the B color paint formed by the rotary atomizing head type coating machine 31 are not affected by the spray air unlike the paint particles discharged by the high pressure air.
Can be applied to the body 12 to form a clear boundary line BL without bouncing off the surface of the body.

The inclination angle α 2 of the rotary atomizing head type coating machine 31 is set in the range of 50 to 80 degrees, and the coating distance between the surface of the body 12 and the edge 33 A of the rotary atomizing head 33 is set. L
2 is described as being set in the range of 5 mm to 20 mm, but these values affect the atomization formation of the paint, such as the outer diameter of the rotary atomizing head 33, the number of revolutions, the type of paint, and the discharge amount. Varies depending on various conditions.

Further, the surface of the body 12 and the rotary atomizing head 3
By making the coating distance L2 between the third edge 33A and the third edge 33A close to 10 mm, the rectifying plate 36 is also arranged close to the body 12, so that the rectifying plate 36 controls the mist suppression air supplied from the air nozzle 35. Guide to the front of the rotary atomizing head 33,
Effective mist suppression air can be formed aiming at the position of the boundary line BL.

Next, the rotary atomizing head type coating machine 41 used in the band-shaped area coating stage 4 disposed downstream of the boundary area coating stage 3 will be described with reference to FIG. The coating machine 41 includes a casing 42 and a rotary atomizing head 4 similar to the coating machine 31 of the boundary area coating stage 3.
3 and includes an air motor (not shown), a feed tube, a shaping air ejection hole, and the like, and can apply a high voltage to the paint. Further, an air nozzle 45 is provided on the distal end side of the stay 44, and a rectifying plate 46 is provided on the distal end side of the casing 42.

In the rotary atomizing head type coating machine 41 of the band-shaped area coating stage 4, the rotary atomizing head 43 faces downward (the band-shaped area c side), similarly to the coating machine 31 of the boundary area coating stage 3. And the angle of inclination α3 at this time
Is set in the range of 50 to 80 degrees, for example, about 70 degrees. At this time, as shown in FIGS. 13 and 15, the surface of the body 12 and the edge 43 of the rotary atomizing head 43 are separated.
The coating distance L3 between A and A is 5 on the boundary coating surface PB1 side.
The coating distance L3 'is larger than the coating distance L3 at the position of the two-dot chain line which is set in the range of 40 mm to 40 mm, for example, about 10 mm, and is separated downward from the boundary coating surface PB1. In addition, from the air nozzle 45, the rotary atomizing head 4
Mist suppression air is supplied toward the front of the mist 3. Further, in the belt-shaped area coating stage 4, shaping air is not used, or even if used, a small amount of air that does not resist the mist suppression air is jetted. further,
No high voltage is applied. Even if a high voltage is applied, -3
The value is suppressed to about 0 kV.

Here, the coating machine 41 is tilted downward by about 70 degrees toward the belt-shaped area c, and the B color is sprayed only by the centrifugal force of the rotary atomizing head 43 to perform the coating. The particles of the paint bounce off the surface of the coating film, and the boundary coating surface P
A band-like (band-like) coating surface PB2 following the boundary coating surface PB1 can be formed without exceeding B1.

Since the belt-like coating surface PB2 painted on the belt-like area painting stage 4 does not form the boundary line BL, the painting distance L3 is 5 mm to 40 mm and the painting distance L2 on the boundary-area painting stage 3 is L2. (5mm-20m
The setting range is wider than that of m). This allows
The band-shaped coating surface PB2 can be formed wider than the boundary coating surface PB1. In the later-described coating work on the remaining area coating stage 5, the lower coating film surface PB3 and the boundary line B
Since the distance between L and L can be secured long, it is possible to more reliably prevent the situation where the particles of the B color paint adhere to the A color paint surface PA beyond the belt-like paint surface PB2 and the boundary paint surface PB1. can do.

Further, in the band-shaped area painting stage 4,
Since the shaping air is not used or is suppressed to a small amount that does not resist the mist suppression air even if used, the B color paint sprayed by the centrifugal force from the rotary atomizing head 43 is disturbed by the shaping air. It is applied to the object without being applied. This can prevent the particles of the B color paint from scattering and adhering to the A color coating surface PA.

Next, the rotary atomizing head type coating machine 51 used in the remaining area coating stage 5 disposed downstream of the belt-shaped area coating stage 4 will be described with reference to FIG. The coating machine 51 includes a casing 52 and a rotary atomizing head 5 similar to the coating machine 21 of the A-color area coating stage 2.
3 and includes an air motor (not shown), a feed tube, a shaping air ejection hole, and the like, and can apply a high voltage to the paint. Further, an air nozzle 55 is provided on the tip side of the stay 54, and a rectifying plate 56 is provided on the tip side of the casing 52.

Then, the rotary atomizing head type coating machine 51 of the remaining area coating stage 5 adjusts the inclination angle α4 of the rotary atomizing head 53.
Is set to approximately 0 degrees, and even if the rotary atomization head 53 is slightly tilted downward (toward the lower area d), it is set to 1 degree to
The range is set to 10 degrees, for example, about 2 degrees. As shown in FIGS. 14 and 15, the coating distance L4 between the surface of the body 12 and the edge 53A of the rotary atomizing head 53 is:
The mist suppression air from the air nozzle 55 is set in a range of 100 mm to 350 mm, for example, about 150 mm.
It is supplied as appropriate depending on the width of the belt-like coating film surface PB2, the type of paint, the surface shape of the body 12, and the like. In the remaining area coating stage 5, as in the case of the A-color area coating stage 2, shaping air is used, and the paint is -30 to -1.
A high voltage of 20 kV is applied.

Here, in the remaining area painting stage 5,
First, the coating machine 51 is tilted downward about 2 degrees toward the lower area d so that the spray direction of the paint is opposite to the A-color coating surface PA. Second, the coating distance L4 is in the range of 100 mm to 350 mm. To the painting distance L on the A-color area painting stage 2
1 (200 mm to 350 mm) and set closer to each other. Third, an air nozzle 55 and a rectifying plate 56 are provided.
By supplying mist suppressing air from the air nozzle 55 to the front of the rotary atomizing head 53, the particles of the B color paint sprayed from the rotary atomizing head 53 cross the band-shaped coating surface PB2 and the boundary coating surface PB1. It prevents adhesion to the A-color coating surface PA.

The two-tone coating apparatus according to the present embodiment has the above-described configuration. Next, a two-tone coating method using the two-tone coating apparatus will be described with reference to the time chart shown in FIG. 16 and the coating shown in FIGS. The operation will be described with reference to the operation explanatory diagram.

First, when the body 12 is mounted on the support base 11A of the conveyor 11 and is conveyed to the coating factory 1, first, the A-color paint, which is the first color area painting step, is applied on the A-color area painting stage 2. The used A-color area painting process is performed.

In the A-color area painting step, the upper half of the body 12 is painted with the A-color paint. That is,
In the A-color area painting process, the arms 15B, 15C and the like of the painting robot 15 are operated, and the rotary atomizing head 23 of the rotary atomizing head type coating machine 21 is substantially moved with respect to the surface of the body 12 as shown in FIG. Place at right angles. The coating distance L1 between the edge 23A of the rotary atomizing head 23 and the surface of the body 12 is set to 200.
mm to 350 mm, keep constant at an arbitrary distance, supply shaping air, and add -30
A high voltage of -120 kV is applied.

In this state, the paint is supplied from the feed tube toward the rotary atomizing head 23, and the paint is sprayed from the rotary atomizing head 23 toward the body 12, whereby the A-color paint charged to a high voltage is obtained. Is applied to the surface of the body 12 as paint particles as shown in FIG. 4 to form an A-color coating surface PA. At this time, the tracking device 13 and the painting robot 15 move the painting machine 21 at the upper half position of the body 12.
As shown in FIG. 17 using the left rear door 12D, the paint is applied to the A-color area a below the boundary line BL indicated by the two-dot chain line. Note that this A
In the color area painting process, the entire body 12 from the top to the bottom may be painted using the A color paint.

Next, after the A-color coating surface PA is formed on the upper portion of the body 12 by the A-color area painting process, the process proceeds to the boundary area painting process. In this boundary area coating step, the inclination angle α2 is set to about 70 degrees so that the rotary atomizing head 33 faces downward (toward the boundary area b), and the coating distance L2 is set to 10 degrees.
mm, mist suppression air is blown out from the air nozzle 35 toward the rectifying plate 36 and supplied to the front side of the rotary atomizing head 33. No shaping air is used and no high voltage is applied.

Further, in the boundary area painting step using the B color paint, the boundary area b is kept in a wet state before the baking furnace is used to bake the A-color coating surface PA coated in the above-described A-color area painting step. The coating operation is performed by so-called wet-on-wet coating.

When the B color paint is supplied from the feed tube to the rotary atomizing head 33, the rotary atomizing head 33 sprays the B color paint only by the centrifugal force generated by the high-speed rotation. As a result, as shown in FIG. 5, the particles of the B color paint are applied to the boundary area b overlapping the A color coating surface PA without rebounding in a converged state before being diffused. The tracking devices 13 and 14 and the painting robots 15 and 16 are
As shown in FIG. 18, the boundary area b is coated by forming the boundary coating surface PB1 by relatively moving the coating machine 2 and the coating machine 31 in the transport direction. This boundary coating surface PB
1 can form a clear boundary line BL.

Here, in the boundary area painting step, FIG.
As shown by the arrow shown in FIG. 3, the body 12 and the coating machine 31 are relatively moved in the transport direction, and the coating machine 31 is moved to the boundary line B.
It reciprocates upward and downward (widthwise) crossing L. Thereby, in the boundary area coating process, the width dimension of the boundary coating surface PB1 is increased, and in the subsequent band-shaped area coating process, it is ensured that particles of the B color coating do not scatter to the A color coating surface PA side. Area can be enlarged.

Here, when the coating machine 31 reciprocates with the coating distance L2 between the surface of the body 12 and the edge 33A of the rotary atomizing head 33 constant, as in the comparative example shown in FIG. In this case, since the operation speed becomes slow at the folded portion R "at the upper end and the lower end of the boundary coating surface PB1", the thickness of the coated film becomes large at the folded portion R ".

However, in the present embodiment, when the coating machine 31 is reciprocated, as shown in FIG.
3 at the position where the edge 33A is to be painted with the boundary line BL.
The minimum coating distance L2 for the surface of No. 2 and the boundary line B
At the position shown by the two-dot chain line spaced downward from L
The coating distance L2 'is larger than 2. By operating the coating machine 31 in this manner, the rotary atomizing head 33 is brought closer to the body 12 on the boundary line BL side of the boundary coating surface PB1, and the boundary line BL is clearly formed by a thick and clear coating film. Can be. On the other hand, at a position away from the boundary line BL of the boundary coating surface PB1, the rotary atomizing head 33
Since it is separated from the substrate, the coating particles can be sprayed over a wide range to form a thin coating film if only one reciprocating operation is performed. Thereby, a flat coating surface can be formed at a position distant from the boundary line BL, that is, at a position where the band-shaped coating surface PB2 overlaps. Good paint finish can be achieved.

In the boundary area painting step, as shown in FIG. 20, after rotating the rotary atomizing head 33 in parallel along the boundary line BL, the rotary atomizing head 33 is again shifted upward and downward. The boundary coating surface PB1 may be painted by reciprocating the painting so as to repeat the operation of moving in parallel.

In the boundary area coating step, mist suppression air is supplied from the air nozzle 35, and the mist suppression air is guided to the front of the rotary atomizing head 33 by the rectifying plate 36 provided at the tip of the casing 32. Thus, the mist suppressing air can prevent the spray particles of the B color paint discharged when forming the boundary coating surface PB1 from scattering to the A color coating surface PA side.

Further, by performing the coating while the shaping air is stopped, a factor that disturbs the directionality of the spray particles of the B color paint discharged from the rotary atomizing head 33 is eliminated.
The boundary line BL of the boundary coating surface PB1 is made clearer.

Next, when the coating of the boundary area b is performed on the lower side of the color A coating film PA in the boundary area coating step,
Move on to the band-shaped area painting process. In the band-shaped area painting step, the inclination angle α3 is set to about 70 degrees so that the rotary atomizing head 43 is directed downward (toward the band-shaped area c), and the coating distance L3 is substantially the same as in the boundary area painting step described above. Is 10 mm
Mist suppression air is ejected from the air nozzle 45. In addition, shaping air is not used, or a small amount of air that does not resist mist suppression air is spouted even if used. In addition, no high voltage is applied. Even if a high voltage is applied, the value is suppressed to about -30 kV.

In this state, when the B color paint is supplied from the feed tube to the rotary atomizing head 43, the rotary atomizing head 43
A-color paint is discharged only by centrifugal force by high-speed rotation. Then, the coating machine 41 is relatively moved along the boundary coating surface PB1, and as shown in FIG.
A belt-like coating is applied to the belt-like area c following 1 to form a belt-like coating film surface PB2.

Further, in the belt-shaped area painting step, the coating machine 41 reciprocates upward and downward crossing the boundary line BL as shown by an arrow in FIG. 22, similarly to the boundary area painting step. Further, during this reciprocating operation, as shown in FIG. 13, the minimum coating distance L3 is set on the upper side which is closer to the boundary coating surface PB1, and the coating distance is set at the position indicated by the two-dot chain line on the lower side which is separated from the boundary coating surface PB1. The coating distance L3 'is larger than the distance L3. Thus, when the lower coating film surface PB3 following the belt-like coating film surface PB2 is applied, the paint finish at the overlapping portion of the coating material can be improved similarly to the boundary coating film surface PB1.

Next, after the strip-shaped area c following the boundary coating film surface PB1 is coated by the strip-shaped area coating step, the process proceeds to the remaining area coating step. In this remaining area painting process,
As shown in FIG. 14, the inclination angle α4 of the rotary atomizing head 53 is
Even if it is set to almost 0 degree, and even if the rotary atomization head 53 is slightly inclined downward (toward the lower area d side), the coating distance L4 is set in the range of 1 to 10 degrees, for example, about 2 degrees. 150
mm. Further, mist suppression air is jetted from the air nozzle 55 to supply shaping air, and a high voltage of -30 to -120 kV is applied to the B color paint.

In this state, the paint is supplied from the feed tube toward the rotary atomizing head 53, and the paint is sprayed from the rotary atomizing head 53 toward the body 12, whereby the B-color paint charged to a high voltage is supplied. Are applied to the surface of the body 12 as paint particles to form a lower coating surface PB3 as shown in FIG. At this time, the tracking device and the painting robot reciprocate the painting machine 51 upward and downward at the lower part of the body 12 as shown by arrows in FIG.
The lower area d following the belt-like coating surface PB2 is painted to form a lower coating surface PB3.

In this manner, the body 12 is formed with the A-color coating surface PA and the B-color coating surface PB including the boundary coating surface PB1, the belt-like coating surface PB2, and the lower coating surface PB3. The body 12 can be painted in two colors (two-tone) of an upper half (color A) and a lower half (color B) with the boundary line BL as a boundary, as shown in FIG.

Next, after the two-tone coating is applied to the body 12, the process proceeds to a clear coating step, as shown in FIG. 1, where the surface is coated with the clear coating.

Next, when the painting operation in each painting step is completed, the process proceeds to a paint baking step. In the paint baking process, the body 12 that has passed through each coating process is transported to a baking furnace, and the A-color coating surface PA painted in the A-color area painting process and the boundary area painting process, the belt-shaped area painting process, and the B color area The B-color coating surface PB formed in the coating process and the clear coating surface formed in the clear coating process are baked on the body 12 together.

As described above, according to the present embodiment, A
Boundary coating surface PB1 that forms boundary line BL on color coating surface PA
When painting, a rotary atomizing head type coating machine 31 having a rotary atomizing head 33 is used in a state of being inclined with respect to the surface of the body 12, and the B color paint is discharged by the centrifugal force of the rotary atomizing head 33. As a result, a clear boundary line BL can be formed with the B color paint.

As a result, in the two-tone coating method according to the present embodiment, the masking operation can be omitted.
It is possible to improve productivity and reduce coating cost.
Moreover, unlike the prior art disclosed in Japanese Patent Application Laid-Open No. 58-58168, there is no need to bring a masking plate or the like into contact with the coating surface, so that the structure can be simplified and the coating quality can be improved to be applied as a finish coating. be able to. Furthermore, in Japanese Patent Application Laid-Open No. 11-57606 described in the prior art, since a two-fluid nozzle coating gun (airbrush gun) is used, the paint sprayed by the spray air is
It bounces off the surface of the object and scatters. However, in the present embodiment, the paint can be reliably applied without the splash of the paint on the surface of the body 12, and the reliability as a two-tone coating without masking work can be improved.

A rotary atomizing head type coating machine 2 is used as a coating machine.
Since 1, 31, 41, and 51 are used, it is possible to cope with coating of a large discharge amount, and it is possible to efficiently atomize a highly viscous paint. As a result, a wide range of coating can be performed in a short time like the body 12 of an automobile, and a high quality coating finish can be obtained.

When painting the boundary area b,
Since the coating machine 31 is reciprocated upward and downward, the boundary coating surface PB1 can be formed to be wide. Moreover,
When the coating machine 31 is reciprocated, the coating distance L2 is set at a position where the rotary atomizing head 33 coats the boundary line BL, and a coating distance L2 'which is larger than the coating distance L2 at a position separated downward from the boundary line BL. And As a result, the boundary coating film surface PB1 becomes a thick and clear coating film on the boundary line BL side, so that the boundary line BL can be clearly formed and the quality can be improved. On the other hand, the boundary coating surface PB1 can eliminate the step between the boundary coating surface PB1 and the belt-like coating surface PB2, thereby improving the coating finish.

Also, when painting the belt-shaped area c,
In the same manner as when coating the boundary area b, the coating machine 41 is reciprocated upward and downward, and the minimum coating distance L3 is set on the boundary coating surface PB1 side, and on the lower side separated from the boundary coating surface PB1 on the lower side. Painting distance L3 greater than painting distance L3
'. Thus, when the lower coating film surface PB3 following the belt-like coating film surface PB2 is applied, the finish of coating of the overlapping portion of the coating material can be improved.

Further, the coating machine 31 of the boundary area coating stage 3 is provided with an air nozzle 35, and the mist suppressing air discharged from the air nozzle 35 is caused to flow along a straightening plate 36 provided at the tip of the casing 32. It can be guided in front of the rotary atomizing head 33. Thereby, the mist suppressing air can suppress the scatter of the spray particles of the B-color paint on the A-color coating surface PA, and can further improve the coating quality. This effect can be obtained in the same manner in the coating machine 41 of the belt-shaped area coating stage 4 and the coating machine 51 of the remaining area coating stage 5.

Next, FIGS. 24 to 27 show the second embodiment of the present invention.
An embodiment will be described. A feature of the present embodiment lies in a two-tone coating method in which a boundary line is formed to be offset to one side in the vertical direction of the body. In this case, two-tone coating is performed by the A-color area coating step, the boundary area coating step, and the belt-shaped area coating step, and the remaining area coating step used in the first embodiment is omitted. Further, in the present embodiment, the same components as those in the above-described first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

Further, in the present embodiment, in the A-color area painting process, the rotary atomizing head type coating machine 21 used in the A-color area painting process in the first embodiment is used, and in the boundary area painting process. In the first embodiment, the rotary atomizing head type coating machine 31 used in the boundary area coating process is used, and in the belt-shaped area coating process, the rotary atomization used in the belt-shaped area coating process in the first embodiment is used. A head type coating machine 41 is used.

Next, the two-tone coating method according to the present embodiment will be described with reference to the time chart shown in FIG. 24 and the coating operation explanatory diagrams shown in FIGS. 25 to 27.

First, in the A-color area painting step, as illustrated by using the left lateral rear door 12D in FIG. 25 under the same painting conditions as in the A-color area painting step according to the first embodiment, a two-dot chain line is used. Is applied to the A color area e below the boundary line BL indicated by.

Here, in the present embodiment, the position of the boundary line BL is set to a position lower than the boundary line BL according to the first embodiment. Thereby, the coating range of the B-color coating film surface PB described later is narrow.

Next, after the A-color coating surface PA is formed on the body 12 by the A-color area painting process, the process proceeds to the boundary area painting process. In this boundary area painting step, as shown in FIG. 26, the boundary area f is painted under the same coating conditions as in the boundary area painting step according to the first embodiment. Thus, the boundary line BL is formed between the boundary coating surface PB4 and the A-color coating surface PA.

Next, when the boundary coating surface PB4 is coated on the lower side of the A-color coating surface PA in the boundary area coating step,
Move on to the band-shaped area painting process. In this strip area coating step, as shown in FIG. 27, under the same coating conditions as in the strip area coating step according to the first embodiment, as shown in FIG.
Is applied to the remaining surface, that is, the belt-like area g, to form a belt-like coating surface PB5 under the body 12.

In this way, the body 12 is composed of the B-color coating surface PA, the boundary coating surface PB4, and the belt-like coating surface PB5.
After the color coating surface PB is formed, a clear coating is applied in a clear coating process, and an A-color paint, a B-color paint,
Bake clear paint.

As described above, according to the present embodiment, as a condition of the two-tone coating, when the position of the boundary line BL is offset to the lower side, for example, the coating range of the B color coating is narrowed. The B-color paint can be applied in only two steps of the border area paint step and the belt-shaped area paint step, omitting the rest area paint step described in the first embodiment, thereby reducing the number of two-tone paint steps. can do.

Next, FIGS. 28 to 33 show a third embodiment of the present invention.
An embodiment will be described. The feature of the present embodiment is that the coating width of the boundary area painting step described in the first embodiment is widened, so that the boundary area painting step and the band area painting step are combined. In other words, the B-color paint is applied by the band-shaped boundary area painting step and the remaining area painting step.

Reference numeral 61 denotes a painting factory according to the present embodiment. Inside the painting factory 61, an A-color area painting stage 62 for performing an A-color area painting step, a zonal boundary area painting stage 63 for performing a zonal boundary area painting step, A remaining area painting stage 64 for performing the remaining area painting process, a clear painting stage 65 for performing the clear painting process, and a paint baking stage 66 for performing the paint baking process are provided.

Here, in the A-color area painting step, the rotary atomizing head type coating machine 21 used in the A-color area painting step in the first embodiment is used. In the embodiment, the rotary atomizing head type coating machine 31 used in the boundary area coating step is used, and in the remaining area coating step, the rotary atomizing head type coating machine used in the remaining area coating step in the first embodiment is used. Use 51.

Next, the two-tone coating method according to the present embodiment will be described with reference to the time chart shown in FIG. 29 and the coating operation explanatory diagrams shown in FIGS. 30 to 33.

First, in the A-color area painting process, as illustrated by using the left lateral rear door 12D in FIG. 30 under the same painting conditions as the A-color area painting process according to the first embodiment, a two-dot chain line is used. Is applied to the A-color area h below the boundary line BL indicated by.

Next, after the A-color coating surface PA is formed on the upper portion of the body 12 by the A-color area painting process, the process proceeds to the band-shaped boundary area painting process. In this strip-shaped boundary area coating step, as shown in FIG. 31, the strip-shaped boundary area j is coated under substantially the same coating conditions as the boundary area coating step according to the first embodiment, and the strip-shaped boundary coating surface PB6 is formed. Form.

Here, in the band-shaped boundary area coating step according to the present embodiment, as shown by the arrow in FIG. 32, the rotary atomization head 33 is moved in parallel along the boundary line BL, and then is again rotated and atomized. Painting is performed such that the operation of moving the head 33 upward and downward and moving it in parallel is repeated a plurality of times. This allows
In the band-shaped boundary area coating process, the width of the band-shaped boundary coating surface PB6 is widened. The safety area is widened to prevent scattering.

Next, A was applied in a strip-shaped boundary area painting step.
After the belt-like boundary coating film surface PB6 is painted near the lower side of the color coating film surface PA, the process proceeds to the remaining area coating process. In this remaining area coating step, as shown in FIG. 33, the rotary atomizing head 53 is moved in parallel along the belt-like boundary coating film surface PB6 under the same coating conditions as the remaining area coating step according to the first embodiment. And
By repeating (reciprocating) these parallel movements shifted upward and downward, the lower area k following the belt-like boundary coating surface PB6 is painted, and the lower coating surface PB7 is formed on the entire lower surface. .

After the A-color coating surface PA and the band-like boundary coating surface PB6 and the lower-color coating surface PB7, the B-color coating surface PB is formed on the body 12, the clear coating process is performed. Is applied, and the A color paint, the B color paint and the clear paint are baked in the paint baking step.

As described above, according to the present embodiment, in the band-shaped boundary area coating step, the boundary line BL is formed by the band-shaped boundary coating film surface PB6, and the band-shaped boundary coating film surface PB6 is Coating surface P according to the embodiment of the present invention
It is formed in a wide band shape to the extent that B1 and the band-shaped coating surface PB2 are added. Therefore, since the band-shaped boundary area painting step can serve as both the boundary area painting step and the band-shaped area painting step according to the first embodiment, the two-tone painting step can be reduced by one step, and the painting robot can be reduced. In addition, costs required for a coating machine and the like can be reduced.

Further, in the band-shaped boundary area painting step, the rotary atomizing head 33 is moved along the boundary line BL. As a result, the boundary line BL formed by the belt-like boundary coating film surface PB6 can be formed smoothly (linearly), and the boundary line BL can be formed more clearly.

In the first embodiment, the case where the coating machine 31 of the boundary area coating stage 3 is provided with the air nozzle 35 at a position separated from the casing 32 via the stay 34 is exemplified. However, the present invention is not limited to this. For example, as in a rotary atomizing head type coating machine 71 according to a modification shown in FIG. A configuration may be provided. This configuration can be similarly applied to the coating machine 41 of the belt-shaped area coating stage 4, the coating machine 51 of the remaining area coating stage 5, and the second and third embodiments.

Further, in the first embodiment, the coating operation is performed by using the rotary atomizing head type coating machine 21 in the A color area coating step and the rotary atomizing head type coating machine 51 in the remaining area coating step. Is illustrated. However, in the case of the present embodiment, in the A color area coating step and the remaining area coating step, the air atomizing nozzle type coating machine and the hydraulic atomizing nozzle type are used instead of the rotary atomizing head type coating machines 21 and 51. The coating may be performed using another coating machine such as a coating machine. Similarly, the A-color area coating process according to the second embodiment includes the A-color area coating process and the remaining area coating process according to the third embodiment including an air atomizing nozzle type coating machine and a hydraulic atomizing nozzle type. Another coating machine such as a coating machine may be used.

On the other hand, in the first embodiment, in the boundary area coating step, the rotary atomizing head 33 moves up and down and reciprocates to perform coating, and moves in parallel along the boundary line BL. The case where the painting is performed by reciprocating while repeatedly shifting the operation upward and downward is exemplified. Third
In the embodiment, the case where the rotary atomizing head 33 is reciprocated while repeating the operation of moving in parallel along the boundary line BL in the band-shaped boundary area coating step to perform the coating is illustrated. However, in the case of the present embodiment, for example, in the boundary area coating step according to each embodiment, the coating is performed by moving the rotary atomizing head 33 only once substantially in parallel with the boundary line BL, and the boundary coating surface is changed. It may be formed.

Further, in each embodiment, the coating robots 15, 16 are provided with the rotary atomizing head type coating machines 21, 31, 41,
Although the case where the painting work was performed with the attachment 51 was described as an example, the present invention is not limited to this.
The coating machine may be mounted on a reciprocator that reciprocates only rightward or upward or downward.

[0148]

As described above in detail, according to the two-tone coating method of the present invention, in the first color area coating step, the surface of the object is coated with the first color coating. The first color coating surface can be formed on the surface of the substrate.

Next, in the boundary area coating step, the rotary atomizing head is disposed at a position close to the object to be coated and inclined toward the boundary area with respect to the object to be coated. Is supplied in front of the rotary atomizing head to prevent mist from being scattered on the surface of the first color coating film, while shaping air for shaping the spray pattern is not supplied, and no high voltage is applied or low pressure is applied. With only a high voltage applied, the rotary atomizing head is rotated at high speed to spray the second color paint.

As a result, the second color paint flies radially outward by centrifugal force while being pulled by the negative pressure region formed in front of the rotary atomizing head when the rotary atomizing head is rotated at high speed. I do. In this case, since the rotary atomizing head is arranged close to the object to be coated, the second color paint is applied to the object to be coated with little scattering before atomization due to air resistance. A simple boundary line can be formed. Also, since the rotary atomizing head is inclined with respect to the object to be coated, the second color paint is sprayed only by centrifugal force without using spray air or the like,
The spray particles can be reliably applied without rebounding and scattering on the surface of the object. Further, the mist suppressing air supplied in front of the rotary atomizing head can prevent the paint mist composed of the second color paint from being scattered on the surface of the first color coating film, thereby improving the paint finish.

Next, in the band-shaped area coating step, the rotary atomizing head is disposed at a position close to the object to be coated and inclined toward the band-shaped area with respect to the object to be coated. Is supplied to the front of the rotary atomizing head to prevent mist from being scattered on the surface of the first color coating film, and without applying a high voltage or applying only a low-voltage high voltage, A wide band-shaped (belt-shaped) coating can be applied to the surface of the object following the boundary line by using the second color coating while reciprocating the head.

As a result, the second color paint is continuously applied to the boundary coating surface in a state where scattering to the first color coating surface is suppressed, in substantially the same manner as the coating operation in the boundary area coating step described above. A coating surface can be formed. At this time, since the rotary atomizing head type coating machine is reciprocated, it is possible to apply the second color paint to a wide surface of the object to be coated following the boundary coating surface.

As a result, the two-tone coating can be performed without using a masking tape or the like, so that the masking work, the intermediate baking work and the like can be omitted, the workability can be improved, and the coating quality can be improved. The coating cost can be reduced.

According to the two-tone coating method of the second aspect of the present invention, in the first color area coating step, the surface of the object is coated with the first color paint so that the surface of the object is coated. The first color coating surface can be formed.

Next, in the boundary area coating step, the rotary atomizing head is arranged at a position close to the object to be coated and inclined toward the boundary area with respect to the object to be coated. Is supplied in front of the rotary atomizing head to prevent mist from being scattered on the surface of the first color coating film, while shaping air for shaping the spray pattern is not supplied, and no high voltage is applied or low pressure is applied. With only a high voltage applied, the rotary atomizing head is rotated at high speed to spray the second color paint.

As a result, the second color paint flies radially outward by centrifugal force while being pulled by the negative pressure region formed in front of the rotary atomizing head when the rotary atomizing head is rotated at high speed. I do. In this case, since the rotary atomizing head is arranged close to the object to be coated, the second color paint can be applied to the object with little scattering before atomization due to air resistance. Thus, a clear boundary line can be formed. Also, since the rotary atomizing head is inclined with respect to the object to be coated, the second color paint is sprayed only by centrifugal force without using spray air or the like, and the spray particles bounce off the surface of the object to be scattered. It can be applied without performing. Further, the mist suppressing air supplied in front of the rotary atomizing head can prevent the paint mist composed of the second color paint from being scattered on the surface of the first color coating film, thereby improving the paint finish.

Next, in the band-shaped area coating step, the rotary atomizing head is arranged at a position close to the object to be coated and inclined toward the band-shaped area with respect to the object to be coated. Is supplied to the front of the rotary atomizing head to prevent mist from being scattered on the surface of the first color coating film, and without applying a high voltage or applying only a low-voltage high voltage, A wide band-like coating is applied to the surface of the object following the boundary line using the second color paint while the head is reciprocated.

As a result, the second color paint is applied in a band-like manner following the boundary paint film in a state where scattering to the first color paint film is suppressed, in substantially the same manner as the painting operation in the above-mentioned border area painting process. A film surface can be formed. Also, in the band-shaped area coating process, a wide band-shaped coating is applied by the reciprocating operation of the rotary atomizing head. Therefore, when the second color paint is applied in the remaining area coating process, it is necessary to cover the first color coating surface. By increasing the distance, it is possible to prevent particles of the second color paint from adhering to the surface of the first color coating film.

Next, in the remaining area coating step, the surface of the object to be coated following the belt-shaped coating film surface is coated with the second color coating. At this time, since the boundary coating surface composed of the second color coating and the band-shaped coating surface are interposed between the coating portion in the remaining area coating process and the first color coating surface, the normal coating operation is performed by the coating machine. In this case, the particles of the second color paint can be prevented from scattering on the surface of the first color coating film.

As a result, the two-tone coating can be performed without using a masking tape or the like, so that masking work, intermediate baking work, and the like can be omitted, workability can be improved, and coating quality can be improved. The coating cost can be reduced.

According to the third aspect of the present invention, in the boundary area coating step, the coating distance between the edge of the rotary atomizing head and the object to be coated at the position where the boundary line with the first color coating surface is coated. With the reciprocating trajectory that increases the coating distance between the edge of the rotary atomizing head and the object to be coated as the distance from the boundary line with the first color coating surface increases. The paint is applied while moving in the direction crossing the line.

Therefore, when coating is performed by reciprocating the rotary atomizing head, the edge of the rotary atomizing head is close to the object to be coated at the position of the boundary with the surface of the first color coating film. At the position of this boundary line, a boundary line composed of a thick and clear coating film surface can be formed. On the other hand, since the edge of the rotary atomizing head is separated from the object to be coated at a position away from the boundary with the first color coating surface, the spray particles should be applied in a wider range than the position of the boundary. Can be. Thereby, a flat coating film surface can be formed at a position away from the boundary line.
As a result, when a band-shaped coating surface following the boundary coating surface is applied, the thickness of the overlapping portion between the boundary coating surface and the band-shaped coating surface can be made uniform, and a good coating finish can be obtained. it can.

According to the fourth aspect of the present invention, in the boundary area coating step, the coating is performed while moving the rotary atomizing head substantially in parallel with the boundary line. Smooth (linear) by rotating atomizing head moving in parallel
The boundary line can be formed, and the boundary line can be formed more clearly.

According to the invention of claim 5, in the belt-shaped area coating step, the coating distance between the edge of the rotary atomizing head and the object to be coated on the boundary coating surface side is minimized, The coating is performed while moving the rotary atomizing head in a direction crossing the boundary with a reciprocating trajectory that increases the coating distance between the edge of the rotary atomizing head and the object to be coated as the distance from the rotary atomizing head increases.

Therefore, at the position on the boundary coating film surface side, the coating distance between the edge of the rotary atomizing head and the object to be coated is minimized to suppress the scattering of the coating, so that the particles of the second color coating can be prevented. Can be prevented from adhering to the first color coating film surface beyond the boundary coating film surface. Further, when the second color coating following the band-shaped coating surface is applied, the spray particles can be applied in a wider range than the position on the boundary coating surface side. Thereby, a flat coating film surface can be formed at a position away from the boundary coating film surface. As a result, when the subsequent coating is applied to the belt-like coating film surface, the film thickness of the overlapping portion of the coating films can be made uniform, and the coating quality can be improved.

According to the sixth aspect of the present invention, in the belt-shaped area coating step, since the coating is performed while reciprocating the rotary atomizing head substantially parallel to the boundary line, the second atomized from the rotary atomizing head is sprayed. Since the color paint is applied almost in parallel with the boundary line, the particles of the second color paint pass over the boundary coating surface and the band-like coating surface and become the first color coating.
It is possible to prevent scattering on the color coating surface.

According to the seventh aspect of the invention, in the belt-shaped area coating step, no shaping air is used or a small amount of shaping air that does not resist the mist suppression air is used. Since the second color paint sprayed by the centrifugal force is applied to the object without being disturbed by the shaping air, particles of the second color paint are scattered and adhere to the first color coating surface. Prevention and high quality coating.

According to the invention of claim 8, the rotary atomizing head type coating machine is provided with an air nozzle for discharging mist suppression air toward the front of the rotary atomizing head. Mist suppression air is supplied from the air nozzle in front of the rotary atomizing head. Therefore, when the mist suppression air is supplied from the air nozzle to the front of the rotary atomizing head, the mist suppression air prevents the paint mist of the second color paint from scattering over the boundary line toward the first color coating surface. Can be prevented, and the reliability for two-tone coating can be improved.

According to the ninth aspect of the present invention, in the rotary atomizing head type coating machine, an air nozzle for discharging mist suppressing air toward the rotary atomizing head, and the mist suppressing air discharged from the air nozzle is rotary atomized. A rectifying plate for guiding the front of the head is provided, and in the boundary area painting step and the belt-shaped area painting step, mist suppressing air is discharged from the air nozzle, and the mist suppressing air is supplied to the front of the rotary atomizing head by the rectifying plate. . Therefore, when the mist suppressing air is supplied from the air nozzle toward the rotary atomizing head, the mist suppressing air can turn to the rotary atomizing head side by hitting the rectifying plate, and the mist suppressing controlled by the rectifying plate. Air is the second
It is possible to prevent the paint mist due to the color paint from being scattered over the boundary line to the first color coating film surface side.

According to the tenth aspect of the present invention, in the boundary area coating step and the belt-shaped area coating step, the rotary atomizing head is inclined by 50 to 80 degrees with respect to a line perpendicular to the surface of the object to be coated. The coating particles discharged by the centrifugal force of the rotary atomizing head can be applied to the surface of the object without being scattered to the first color coating surface.

In the two-tone coating method according to the eleventh aspect of the present invention, in the first color area coating step, the surface of the object is coated with the first color paint, whereby the surface of the object is coated. The first color coating surface can be formed.

Next, in the band-shaped boundary area coating step, the rotary atomizing head is disposed at a position close to the object to be coated and inclined toward the band-shaped boundary area with respect to the object to be coated, and is made of the second color paint. The mist suppression air for suppressing the paint mist from being scattered on the first color coating surface is supplied in front of the rotary atomizing head, while the shaping air for shaping the spray pattern is not supplied, and the high voltage is not applied. Alternatively, the second color paint is sprayed by rotating the rotary atomizing head at a high speed while reciprocating the rotary atomizing head in a state where only a low voltage high voltage is applied.

Thus, the second color paint flies radially outward by centrifugal force while being pulled by the negative pressure area formed in front of the rotary atomizing head when the rotary atomizing head is rotated at high speed. I do. In this case, since the rotary atomizing head is arranged close to the object to be coated, the second color paint is applied to the object to be coated with little scattering before atomization due to air resistance. A simple boundary line can be formed. Also, since the rotary atomizing head is inclined with respect to the object to be coated, the second color paint is sprayed only by centrifugal force without using spray air or the like,
The spray particles can be applied without splashing and splashing on the surface of the object to be coated. Further, the mist suppressing air supplied in front of the rotary atomizing head can prevent the paint mist composed of the second color paint from being scattered on the surface of the first color coating film, thereby improving the paint finish.

Next, in the remaining area coating step, the surface of the object to be coated following the band-shaped boundary coating film surface can be coated with the second color paint. At this time, since a wide band-shaped boundary coating surface made of the second color paint is interposed between the coating portion in the remaining area coating process and the first color coating surface, normal coating work is performed by a coating machine. Even in this case, it is possible to prevent the particles of the second color paint from scattering on the surface of the first color coating film.

As a result, the two-tone coating can be performed without using a masking tape or the like, so that the masking work, the intermediate baking work and the like can be omitted, the workability can be improved, and the coating quality can be improved. The coating cost can be reduced.

According to the twelfth aspect of the present invention, in the band-shaped boundary area coating step, the coating between the edge of the rotary atomizing head and the object to be coated is performed at a position where the boundary line with the first color coating surface is coated. With the reciprocating trajectory that minimizes the distance and increases the coating distance between the edge of the rotary atomizing head and the object to be coated as the distance from the boundary with the first color coating surface increases, the rotary atomizing head is The paint is applied while moving in the direction crossing the boundary.

Therefore, when the rotary atomizing head is reciprocated to perform coating, the rotary atomizing head is close to the object to be coated at the position of the boundary with the first color coating film surface. At the position of the line, a boundary line composed of a thick and clear coating surface can be formed. On the other hand, at a position away from the boundary with the first color coating film surface, the rotary atomizing head is separated from the object to be coated, so that spray particles can be applied over a wider range than at the position of the boundary. Thereby, a flat coating film surface can be formed at a position away from the boundary line. As a result,
When a coating subsequent to the band-shaped boundary coating film surface is applied, the film thickness of the overlapping portion of the coating films can be made uniform, and a good coating finish can be obtained.

According to the thirteenth aspect of the present invention, in the belt-shaped boundary area coating step, the coating is performed while moving the rotary atomizing head substantially in parallel with the boundary line. A substantially (linear) boundary can be formed by the rotary atomizing head moving almost in parallel.

According to the fourteenth aspect of the present invention, the rotary atomizing head type coating machine is provided with an air nozzle for discharging mist suppressing air toward the front of the rotary atomizing head. Mist suppression air is supplied in front of the atomizing head. Therefore, when the mist suppression air is supplied from the air nozzle to the front of the rotary atomizing head, the mist suppression air prevents the paint mist of the second color paint from scattering over the boundary line toward the first color coating surface. Can be prevented, and the reliability for two-tone coating can be improved.

According to the invention of claim 15, in the rotary atomizing head type coating machine, an air nozzle for discharging mist suppressing air toward the rotary atomizing head, and the mist suppressing air discharged from the air nozzle is rotary atomized. A rectifying plate is provided in front of the head, and mist suppressing air is discharged from the air nozzle in the band-shaped boundary area painting step, and the mist suppressing air is supplied to the front of the rotary atomizing head by the rectifying plate. Therefore, when the mist suppressing air is supplied from the air nozzle toward the rotary atomizing head, the mist suppressing air can turn to the rotary atomizing head side by hitting the rectifying plate, and the mist suppressing controlled by the rectifying plate. The air can prevent the paint mist of the second color paint from being scattered across the boundary line toward the first color paint film side.

According to the sixteenth aspect of the invention, in the belt-shaped boundary area coating step, the rotary atomizing head is inclined by 50 to 80 degrees with respect to a line perpendicular to the surface of the object to be coated. The paint particles discharged by the centrifugal force can be applied to the surface of the object without being scattered toward the first color coating film surface side.

According to the seventeenth aspect, after each coating step is completed, a paint baking step of simultaneously baking the first color paint and the second color paint applied in each coating step is performed. Therefore, after applying the first color paint, the second color paint is applied in a wet state before the coating surface of the first color paint is baked and dried and hardened, that is, a so-called wet on wet (wet on wet) method. ) Allows the painting operation to be performed. For this reason, the paint baking step after the first color area painting step, which was required when performing the masking work in the prior art, can be omitted, and the work process can be simplified and the painting cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a coating process in a coating factory for performing a two-tone coating method according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a two-tone coating apparatus according to the first embodiment of the present invention.

FIG. 3 is an external view showing a left lateral rear door on which two-tone painting is applied.

FIG. 4 is an external view showing the rotary atomizing head type coating machine of the A-color area coating stage together with a part of a body in an enlarged manner.

FIG. 5 is an enlarged external view showing a rotary atomizing head type coating machine of a boundary area coating stage together with a part of a body.

FIG. 6 is an enlarged perspective view showing the air nozzle alone.

FIG. 7 is an enlarged perspective view showing another air nozzle alone.

FIG. 8 is an operation explanatory view showing a state in which paint is being ejected from a rotary atomizing head.

FIG. 9 is an external view showing a state in which a paint is applied to the body by a coating machine disposed substantially at right angles to the surface of the body.

FIG. 10 is an external view showing a coating pattern applied by a coating machine according to a comparative example.

FIG. 11 is an external view showing a boundary formed by coating a boundary coating film surface with a coating machine according to a comparative example.

FIG. 12 is an external view showing a state in which a rotary atomizing head type coating machine of a boundary area coating stage is fixed to perform coating.

FIG. 13 is an enlarged external view showing a rotary atomizing head type coating machine of a band-shaped area coating stage together with a part of a body.

FIG. 14 is an enlarged external view showing a rotary atomizing head type coating machine of a remaining area coating stage together with a part of a body.

FIG. 15 is a condition explanatory view showing painting conditions in each painting area.

FIG. 16 is a time chart showing a two-tone coating method.

FIG. 17 is an explanatory view of a painting operation showing a state in which an A-color coating surface is formed on a door in an A-color area painting step.

FIG. 18 is an explanatory view of a coating operation showing a state where a boundary coating surface is formed on a door in a boundary area coating step.

FIG. 19 is an explanatory view showing a coating operation in which a boundary coating surface painted by reciprocating a rotary atomizing head in a direction crossing a boundary line is enlarged.

FIG. 20 is an explanatory view showing a coating operation in which a boundary coating film surface painted by reciprocating a rotary atomizing head in parallel along a boundary line is enlarged.

FIG. 21 is an external view showing a state in which a door is reciprocated by a coating machine according to a comparative example.

FIG. 22 is an explanatory view of a painting operation showing a state in which a belt-like coating film surface is formed on a door in a belt-like area painting step.

FIG. 23 is an explanatory view of a coating operation showing a state where a lower coating film surface is formed on a door in a remaining area coating step.

FIG. 24 is a time chart showing a two-tone coating method according to the second embodiment of the present invention.

FIG. 25 is an explanatory view of a painting operation showing a state in which an A-color coating surface is formed on the door in the A-color area painting step.

FIG. 26 is an explanatory view of a coating operation showing a state where a boundary coating surface is formed on a door in a boundary area coating step.

FIG. 27 is an explanatory view of a painting operation showing a state where a belt-like coating film surface is formed on a door in a belt-like area painting step.

FIG. 28 is an explanatory diagram showing a coating process in a coating factory for performing a two-tone coating method according to a third embodiment of the present invention.

FIG. 29 is a time chart showing a two-tone coating method according to a third embodiment of the present invention.

FIG. 30 is an explanatory view of a painting operation showing a state in which an A-color coating surface is formed on the door in the A-color area painting step.

FIG. 31 is an explanatory view of a coating operation showing a state in which a band-shaped boundary coating film surface is formed on a door in a band-shaped boundary area coating step.

FIG. 32 is an explanatory view showing a coating operation in which a rotary boundary atomizing head is reciprocated in parallel along a boundary line to enlarge and display a band-shaped boundary coating film surface.

FIG. 33 is an explanatory view of a coating operation showing a state where a lower coating film surface is formed on a door in a remaining area coating step.

FIG. 34 is an external view showing a rotary atomizing head type coating machine according to a modification of the present invention.

FIG. 35 is a flowchart showing a two-tone coating method according to the prior art.

FIG. 36 is an external view showing a two-fluid nozzle coating gun and the like used in a two-tone coating method according to a second conventional technique.

[Explanation of symbols]

2,62 A color area painting stage 3 Boundary area painting stage 4 Strip area painting stage 5,64 Remaining area painting stage 6,65 Clear painting stage 7,66 Paint baking stage 11 Conveyor 12 Body (substrate) 15,16 Coating robot 21, 31, 41, 51, 71 Rotary atomizing head type coating machine 23, 33, 43, 53, 73 Rotary atomizing head 23A, 33A, 43A, 53A Edge 35, 35 ', 45, 55, 74 Air nozzles 36, 46, 56, 75 Rectifier plate 37 Negative pressure area PA A color coating surface (first color coating surface) PB, PB 'B color coating surface PB1, PB1', PB1 ", PB4 Boundary coating Surface BL, BL 'Boundary line PB2, PB5 Strip coating surface PB3, PB7 Lower coating surface (second color coating surface) PB6 Strip boundary coating surface α1, α2, α3, α4 Rotary atomizing head Inclination angle of the instrumentation unit L1, L2, L2 ', L3, L3', L4 painting distance b, f boundary area c, g belt area j belt boundary area

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) B05D 1/32 B05D 1/32 Z 7/14 7/14 L (72) Inventor Shinichi Takayama Minato-ku, Tokyo 5-39, Akasaka F-term in AB Co., Ltd. (Reference) 4D073 AA01 BB03 DB10 DB28 4D075 AA10 AA38 AD18 CB37 DA23 DB02 DC12 4F034 CA22 DA24

Claims (17)

[Claims] [A] A first color area painting step of applying a first color paint on the surface of an object to be coated; [B]. (1). Rotation of a rotary atomizing head type coating machine The atomizing head is disposed at a position close to the object to be coated and tilted toward the boundary area with respect to the object to be coated, and (2) a paint mist composed of the second color paint scatters on the first color coating surface (3). No shaping air for shaping the spray pattern is supplied, and (4). No high voltage is applied or low-voltage high voltage is supplied. (5).
A boundary area painting step of forming a boundary line with the first color coating film surface using the second color paint, [C]. (1). (2). A mist suppressing air for preventing the paint mist composed of the second color paint from scattering on the surface of the first color paint film is disposed on the rotary atomizing head. (3) With no high voltage applied or with only a low-voltage high voltage applied, (4). Coating object following the boundary coating surface while reciprocating the rotary atomizing head A two-tone coating method, comprising: applying a band-like coating to the surface of the surface using a second color paint. 2. [A]. A first color area painting step of applying a first color paint on the surface of the object to be coated, and [B]. (1). Rotation of a rotary atomizing head type coating machine. The atomizing head is disposed at a position close to the object to be coated and tilted toward the boundary area with respect to the object to be coated, and (2) a paint mist composed of the second color paint scatters on the first color coating surface (3). No shaping air for shaping the spray pattern is supplied, and (4). No high voltage is applied or low-voltage high voltage is supplied. (5).
A boundary area painting step of forming a boundary line with the first color coating film surface using the second color paint, [C]. (1). (2). A mist suppressing air for preventing the paint mist composed of the second color paint from scattering on the surface of the first color paint film is disposed on the rotary atomizing head. (3) With no high voltage applied or with only a low-voltage high voltage applied, (4). Coating object following the boundary coating surface while reciprocating the rotary atomizing head Applying a band-like coating to the surface of the second color paint using a second color paint, [D]. The second color paint is applied to the surface of the remaining workpieces not painted by the above-mentioned band-like area paint step. A two-tone painting method comprising a rest area painting process in which painting is performed by using. 3. The boundary area coating step includes the steps of: (1) minimizing a coating distance between an edge of the rotary atomizing head and an object to be coated at a position where a boundary line with the first color coating surface is coated; (2) With a reciprocating trajectory that increases the coating distance between the edge of the rotary atomizing head and the object to be coated as the distance from the boundary with the first color coating surface increases, and (3). 3. The two-tone coating method according to claim 1, wherein the coating is performed while moving the atomizing head in a direction crossing the boundary. 4. The two-tone coating method according to claim 1, wherein in the boundary area coating step, the rotary atomizing head is coated while moving substantially parallel to the boundary line. 5. The strip-shaped area coating step comprises the steps of: (1) minimizing the coating distance between the edge of the rotary atomizing head and the workpiece on the boundary coating surface side; With a reciprocating trajectory that increases the coating distance between the edge of the rotary atomizing head and the object to be coated as it moves away from the surface, (3). Painting while moving the rotary atomizing head in a direction crossing the boundary line The two-tone coating method according to claim 1 or 2, wherein the two-tone coating method is performed. 6. The two-tone coating method according to claim 1, wherein, in the band-shaped area coating step, the rotary atomizing head is coated while reciprocating substantially parallel to the boundary line. 7. The belt-shaped area coating step does not use shaping air or uses a small amount of shaping air that does not resist the mist suppression air.
Or the two-tone coating method according to 2. 8. The rotary atomizing head type coating machine is provided with an air nozzle for discharging mist suppression air toward the front of the rotary atomizing head. In the boundary area coating step and the belt-shaped area coating step, the rotary nozzle atomizes from the air nozzle. The two-tone coating method according to claim 1 or 2, wherein mist suppression air is supplied in front of the head. 9. The rotary atomizing head type coating machine includes an air nozzle for discharging mist suppressing air toward the rotary atomizing head, and a rectifier for guiding the mist suppressing air discharged from the air nozzle to a front of the rotary atomizing head. The mist suppressing air is discharged from the air nozzle in the boundary area painting step and the belt-like area painting step, and the mist suppressing air is supplied to the front of the rotary atomizing head by the rectifying plate. The described two-tone painting method. 10. The method according to claim 1, wherein, in the boundary area coating step and the belt-shaped area coating step, the rotary atomizing head is inclined by 50 to 80 degrees with respect to a line perpendicular to the surface of the object to be coated. Two-tone painting method. 11. A first color area painting step of applying a first color paint on the surface of the object to be coated, and [B]. (1) rotating a rotary atomizing head type coating machine. The atomization head is arranged at a position close to the object to be coated and inclined with respect to the object to be coated toward the band-shaped boundary area. (2). Mist suppression air for suppressing scattering is supplied in front of the rotary atomizing head, and (3) shaping air for shaping the spray pattern is not supplied; (4) high voltage is not applied or low pressure is applied. With only voltage applied,
(5) a band-shaped boundary area coating step of applying a band-shaped coating using a second color paint while forming the boundary with the first color coating surface while reciprocating the rotary atomizing head; [C] . A two-tone coating method, comprising a step of applying a second color coating to the surface of the remaining object not coated in the band-shaped boundary area coating step, using a second color coating. 12. In the step of coating a strip-shaped boundary area, (1).
Minimize the coating distance between the edge of the rotary atomizing head and the object to be coated at the position where the boundary line with the first color coating surface is coated, (2).
A reciprocating trajectory that increases the coating distance between the edge of the rotary atomizing head and the object to be coated as the distance from the boundary with the first color coating surface increases (3). The two-tone coating method according to claim 11, wherein the coating is performed while moving in a direction intersecting with the coating. 13. The two-tone coating method according to claim 11, wherein, in the band-shaped boundary area coating step, the rotary atomizing head is coated while moving substantially parallel to the boundary line. 14. The rotary atomizing head type coating machine is provided with an air nozzle for discharging mist suppression air toward the front of the rotary atomizing head, and in the band-shaped boundary area coating step, the air nozzle is arranged in front of the rotary atomizing head from the air nozzle. The two-tone coating method according to claim 11, wherein mist suppression air is supplied. 15. The rotary atomizing head type coating machine has an air nozzle for discharging mist suppressing air toward the rotary atomizing head, and a rectifier for guiding the mist suppressing air discharged from the air nozzle to the front of the rotary atomizing head. The two-tone coating method according to claim 11, wherein a mist-suppressing air is discharged from the air nozzle in the strip-shaped boundary area painting step, and the mist-suppressing air is supplied in front of the rotary atomizing head by a rectifying plate. 16. In the strip-shaped boundary area coating step, the rotary atomizing head is set at 50 degrees to a line perpendicular to the surface of the object to be coated.
The two-tone coating method according to claim 11, wherein the two-tone coating method is inclined by 80 degrees. 17. A paint baking step of simultaneously baking the first color paint and the second color paint applied in each coating step after each of the coating steps is completed. Two-tone painting method.