JP7848664B2 - Painting system - Google Patents

Description

This disclosure relates to a painting system.

Conventionally, vehicle bodies are painted by spraying paint in a paint booth (for example, Patent Document 1). Generally, multiple paint films are formed in layers during the painting process. The type and number of paint films formed vary depending on the vehicle type.

Japanese Patent Publication No. 2004-354054

In the manufacturing line where the painting process takes place, the type and number of paint films to be formed are predetermined. Therefore, painting multiple vehicle models with different paint configurations can sometimes be difficult.

This disclosure can be implemented in the following forms:
According to one embodiment of the present disclosure, a painting system is provided for performing painting. The painting system includes a first painting booth for forming a first paint layer on a vehicle body, a second painting booth for forming a second paint layer on the vehicle body that is different from the first paint layer, and a first transport line for supporting and transporting the vehicle body in a transport direction, the first transport line passing through the first painting booth and the second painting booth, and a second transport line for supporting and transporting the vehicle body in the transport direction, the first transport line passing through the first painting booth and the second painting booth without passing through the first painting booth, at a connection point on the first transport line between the first painting booth and the second painting booth. The second paint booth comprises a second transport line connected to the first transport line, the first paint layer includes a first paint film, the second paint layer includes at least a second paint film and a third paint film, the second and third paint films are colored, and the second and third paint films are different in color from each other, and in the second paint booth, a first forming step of forming the second paint film on the outer panel of the vehicle body, a second forming step of forming the third paint film on the inner panel of the vehicle body, and a third forming step of forming the third paint film on the outer panel are performed in this order.

(1) According to a first embodiment of the present disclosure, a painting system is provided for performing painting. This painting system comprises: a first painting booth for forming a first paint layer on a vehicle body; a second painting booth for forming a second paint layer on the vehicle body that is different from the first paint layer; a first transport line for supporting and transporting the vehicle body in a transport direction, the first transport line passing through the first painting booth and the second painting booth; and a second transport line for supporting and transporting the vehicle body in the transport direction, the second transport line connecting to the first transport line at a connection point on the first transport line between the first and second painting booths without passing through the first painting booth. According to this embodiment, a first paint layer and a second paint layer can be formed on the vehicle body using the first transport line, and a second paint layer can be formed on the vehicle body without forming the first paint layer using the second transport line. Therefore, painting of different vehicle types can be easily performed.
(2) A painting system of the above form, wherein the first painting booth is located upstream of the second painting booth, and the painting system further comprises an electrodeposition booth for performing electrodeposition painting upstream of the first painting booth on the first transport line, and the second transport line may branch off from a branching point on the first transport line between the electrodeposition booth and the first painting booth. With this form, regardless of the vehicle type, electrodeposition painting can be performed using the same electrodeposition booth by transporting the vehicle body using the first transport line.
(3) A painting system of the above form, further comprising: an acquisition unit for acquiring an identifier pre-assigned to the vehicle body; a storage unit for storing painting information in which the identifier and a painting film configuration composed of a plurality of paint films are pre-associated; and a switching mechanism disposed at the branching point for switching the destination of the vehicle body to either the first transport line or the second transport line, wherein the switching mechanism may switch the transport destination using the identifier and painting information acquired by the acquisition unit. According to this form, the transport destination of the vehicle body can be automatically switched by the switching mechanism depending on the vehicle type.
(4) A painting system of the above form, wherein the vehicle body has a plurality of vehicle types, each having a different coating configuration composed of a plurality of coating films, the first coating layer includes at least a first coating film, the second coating layer includes at least a second coating film, the plurality of vehicle types include a first vehicle type whose coating configuration does not include the first coating film but includes at least a single layer of the second coating film, and a second vehicle type whose coating configuration includes at least a single layer of the first coating film and a single layer of the second coating film, the first painting booth is located upstream of the second painting booth and is configured to form a single layer of the first coating film, and the second painting booth may be configured to form a single layer of the second coating film. According to this form, the vehicle body of the second vehicle type can be transported to the first transport line and the first coating film and the second coating film can be formed sequentially on the vehicle body.
(5) A painting system of the above form, wherein the second coating layer further includes a third coating and a fourth coating, the first vehicle model further includes a single layer of the third coating and a single layer of the fourth coating in its coating configuration, the second vehicle model further includes a single layer of the third coating and a single layer of the fourth coating in its coating configuration, the plurality of vehicle models further include a third vehicle model in which the coating configuration includes at least a single layer of the first coating, a single layer of the second coating, a single layer of the third coating, and a single layer of the fourth coating, and at least one of the first coating and the fourth coating is a plurality of layers, and the first painting booth may be configured to form either a single layer of the first coating or a single layer of the fourth coating on the vehicle body passing through it. According to this form, the third vehicle model in which a plurality of layers of the fourth coating are formed can be painted using the first painting booth, the production capacity of the second painting booth can be optimized, and the painting process can be carried out efficiently.
(6) A painting system of the above form, wherein the first coating layer includes a first coating, the second coating layer includes at least a second coating and a third coating, the second coating and the third coating are colored, and the second coating and the third coating are different in color from each other, and in the second painting booth, a first forming step of forming the second coating on the outer panel of the vehicle body, a second forming step of forming the third coating on the inner panel of the vehicle body, and a third forming step of forming the third coating on the outer panel may be performed in this order. According to this form, even if paint of the second coating adheres to the inner panel of the vehicle body in the first forming step, the second coating is concealed by the third coating formed in the second forming step, thus suppressing a deterioration in the aesthetic appearance of the vehicle.
(7) A painting system of the above form, wherein the first painting booth is located upstream of the second painting booth and further comprises a third transport line that supports the vehicle body and transports it in the opposite direction to the transport direction, and the third transport line branches off from a first point on the first transport line between the first painting booth and the second painting booth and merges with the first transport line at a second point upstream of the first painting booth on the first transport line. According to this form, by using the third transport line, a vehicle body on which multiple layers of the first paint film are formed can be painted efficiently.
(8) A painting system of the above form, further comprising a fourth transport line that supports the vehicle body and transports it in the opposite direction to the transport direction, the fourth transport line branching off from a third point downstream of the second paint booth on the first transport line and merging at a fourth point upstream of the first paint booth on the first transport line. According to this form, the vehicle body can be efficiently painted by using the fourth transport line to transport the vehicle body to the first paint booth and painting the fourth paint film in the first paint booth, thereby forming multiple layers of the fourth paint film on the vehicle body.
(9) A painting system of the above form, comprising a fifth transport line that supports the vehicle body and transports it in the opposite direction to the transport direction, the fifth transport line branching off from a fifth point downstream of the second paint booth on the first transport line and merging at a sixth point on the first transport line between the first paint booth and the second paint booth. According to this form, by using the fifth transport line, each of the multiple second base coatings of different colors can be efficiently painted onto the vehicle body.
(10) A painting system is provided according to a second embodiment of the present disclosure. This painting system paints the bodies of multiple vehicle types, each having a different coating film configuration, and comprises: a first paint booth for forming coating films other than the common coating film for each of the multiple vehicle types; a second paint booth for forming the common coating film; a first transport line for supporting and transporting the vehicle body in the transport direction, passing through the first paint booth and the second paint booth; and a second transport line for supporting and transporting the vehicle body in the transport direction, passing through the first paint booth and the second paint booth without passing through the first paint booth, and connecting with the first transport line at a connection point on the first transport line between the first paint booth and the second paint booth. According to this embodiment, regardless of the vehicle type, a common coating film can be formed for multiple vehicle types by passing the vehicle body through the second paint booth. Furthermore, the coating films other than the common coating film for multiple vehicle types can be painted using the first paint booth, making it easy to paint different vehicle types.
(11) A painting system according to the above embodiment, wherein the plurality of vehicle types include a first vehicle type whose coating configuration does not include a first coating film but includes a second coating film and a third coating film, and a second vehicle type whose coating configuration includes the first coating film, the second coating film and the third coating film, and the first painting booth is configured to be able to paint the first coating film as a coating film other than the common coating film, and the second painting booth is configured to be able to paint the second coating film and the third coating film as the common coating film. According to this embodiment, for the vehicle body of the first vehicle type, the second coating film and the third coating film can be formed using a second transport line without forming the first coating film. For the vehicle body of the second vehicle type, the first coating film, the second coating film and the third coating film can be formed sequentially on the vehicle body.
(12) A painting system of the above form, wherein the first vehicle model includes the second coating film and the third coating film as single layers each, and also includes a single layer of the fourth coating film; the second vehicle model includes the first coating film, the second coating film and the third coating film as single layers each, and also includes a single layer of the fourth coating film; and the plurality of vehicle models further include a third vehicle model in which the coating film configuration includes at least a single layer of the first coating film, a single layer of the second coating film, a single layer of the third coating film and a single layer of the fourth coating film, and at least one of the first coating film and the fourth coating film is in multiple layers; and the first paint booth may be configured to form either the first coating film or the fourth coating film on the vehicle body passing through it. According to this form, the third vehicle model in which the fourth coating film is formed in multiple layers can be painted using the first paint booth, and the production capacity of the second paint booth can be optimized to efficiently carry out the painting process performed by the painting system.
This disclosure can also be implemented in various forms other than painting systems. For example, it can be implemented in the form of a painting method.

A schematic diagram showing the configuration of the painting system. A diagram illustrating the first paint booth. A table showing the correspondence between vehicle models and paint film composition. A diagram illustrating information about the coating film. A flowchart showing the painting process for the second vehicle model. A table summarizing the transport routes in the painting systems for each vehicle model.

A. Embodiments:
A1. Painting system configuration:
Figure 1 is a schematic diagram showing the configuration of a painting system 1 that paints a vehicle body CB. Figure 2 is a diagram illustrating the first painting booth B1. Figure 3 is a table showing the correspondence between vehicle type and paint film configuration. Figure 4 is a diagram illustrating the painting information 24, which will be described later. As shown in Figure 1, the painting system 1 comprises an electrodeposition painting area Ae, a first painting area A1, a second painting area A2, and a plurality of transport lines C. The plurality of transport lines C include a first transport line C1, a second transport line C2, a third transport line C3, a fourth transport line C4, a fifth transport line C5, and a sixth transport line C6. The transport lines C support and transport the vehicle body CB. The electrodeposition painting area Ae, the first painting area A1, and the second painting area A2 are arranged in this order. The first transport line C1 passes through the electrodeposition painting area Ae, the first painting area A1, and the second painting area A2 in order. The first transport line C1 transports the vehicle body CB in the transport direction from the electrodeposition coating area Ae towards the second coating area A2.

The electrodeposition coating area Ae is the area for forming an electrodeposition coating film on the vehicle body CB. The electrodeposition coating area Ae comprises an electrodeposition booth Be and a drying oven Fe. An electrodeposition liquid tank (not shown) containing the electrodeposition coating liquid is located in the electrodeposition booth Be.

The first painting area A1 is the area for forming the intermediate coating, which serves as the first coating, on the vehicle body CB. Within the first painting area A1, the first painting booth B1 and the drying oven F1 are arranged in this order from upstream to downstream in the transport direction.

The second painting area A2 is an area for sequentially forming the first base coating (second coating), the second base coating (third coating), and the clear coating (fourth coating) on the vehicle body CB. The second painting area A2 contains the second painting booth B2, a PH furnace F2, and a drying furnace F3. The second painting booth B2 includes the upstream second painting booth B2a and the downstream second painting booth B2b. The upstream second painting booth B2a, PH furnace F2, downstream second painting booth B2b, and drying furnace F3 are arranged in this order from upstream to downstream in the transport direction within the second painting area A2.

The second transport line C2 is used to paint the first vehicle model, which does not form an intermediate coating. The second transport line C2 branches off from branching point Pa on the first transport line C1 upstream of the first paint booth B1, and connects to the first transport line C1 at connection point Pb on the first transport line C1 between the first paint booth B1 and the second paint booth B2, without passing through the first paint booth B1.

The third transport line C3 is used for painting a third vehicle model, which involves forming multiple layers of intermediate coating. The third transport line C3 transports the vehicle body CB in the reverse direction of the transport. The third transport line C3 branches off from point PO1 on the first transport line C1, located between the first paint booth B1 and the second paint booth B2, and rejoins the first transport line C1 at point PO2, located upstream of the first paint booth B1 on the first transport line C1.

The fourth transport line C4 is used for painting the third vehicle type, which has multiple layers of clear coating. The fourth transport line C4 transports the vehicle body CB in the reverse direction of the transport. The fourth transport line C4 branches off from point PO3, located downstream of the second paint booth B2 on the first transport line C1, and merges with the first transport line C1 at point PO4, located upstream of the first paint booth B1 on the first transport line C1.

The fifth transport line C5 is used for painting so-called two-tone vehicle models, where the vehicle body CB is painted in two different colors. Here, "vehicle body color" refers to the exterior color of the vehicle. The fifth transport line C5 transports the vehicle body CB in the reverse direction of the transport. The fifth transport line C5 branches off from point PO5, located downstream of the second paint booth B2 on the first transport line C1, and merges with the first transport line C1 at point PO6, located between the first and second paint booths B1 and C2 on the first transport line C1.

The sixth transport line C6 is used to paint the third vehicle type, which has multiple layers of clear coating. The sixth transport line C6 transports the vehicle body CB in the transport direction. The sixth transport line C6 branches off from point PO7 on the first transport line C1, located between the first paint booth B1 and the second paint booth B2, and rejoins the first transport line C1 at point PO8, located downstream of the first paint booth B1, without passing through the second paint booth B2.

As shown in Figure 2, the first paint booth B1 is separated from the outside by a partition wall 32. The first transport line C1 is realized by a conveyor located on the underside of the first paint booth B1. The vehicle body CB is fixed to a support member 36 that is transported by the conveyor, and the vehicle body CB is transported by the first transport line C1. An IC tag 38, which stores the vehicle number as an identifier pre-assigned to the vehicle body CB, is attached to the support member 36. An acquisition unit 12 is located near the first transport line C1. In this embodiment, the acquisition unit 12 acquires the vehicle number stored in the passing IC tag 38 by communicating with the IC tag 38.

A painting robot 34 is positioned in the first painting booth B1. The painting robot 34 sprays paint towards the vehicle body CB being transported by the first transport line C1. This coats the vehicle body CB with paint. Note that the spraying of paint onto the vehicle body CB is not limited to the painting robot 34; it may also be performed by an operator.

In painting system 1, painting is performed on the vehicle body CB of multiple vehicle models. In this embodiment, the coating structure, consisting of multiple coating films on the electrodeposited coating, is predetermined for each vehicle model.

As shown in Figure 3, the coating structure of the first vehicle model lacks an intermediate coating, and consists of a single layer each of a first base coating, a second base coating, and a clear coating. The coating structure of the second vehicle model consists of a single layer each of an intermediate coating, a first base coating, a second base coating, and a clear coating. The coating structure of the third vehicle model consists of at least one layer each of an intermediate coating, a first base coating, a second base coating, and a clear coating, and also has two layers of either the intermediate coating or the clear coating. A coating structure with two layers of intermediate coating is also called "double intermediate coating." Similarly, a coating structure with two layers of clear coating is also called "double clear coating."

A single layer of intermediate coating is also called the first coating layer. A coating layer consisting of a single layer of first base coating, a single layer of second base coating, and a single layer of clear coating is also called the second coating layer.

As shown by the black circles in Figure 3, the coatings common to the coating configurations of the first, second, and third vehicle models are the laminated first base coating, second base coating, and clear coating.

The intermediate coating is primarily for providing chipping resistance to the vehicle body (CB). The first and second base coatings are primarily for providing the vehicle body color to the CB. In this embodiment, the first base coating also has the function of providing sufficient chipping resistance to the CB even when the intermediate coating is not formed on the CB. The clear coating is primarily for providing gloss and smoothness.

The first and second base coatings are colored. Furthermore, the first and second base coatings have different colors from each other. The second base coating imparts the body color to the vehicle body CB. The first base coating conceals the substrate and improves the color development of the second base coating. In this embodiment, the second base coating has four or more colors. Also, in this embodiment, the first base coating has three colors. The color of the first base coating is selected according to the color of the second base coating. Note that the number of colors in the first and second base coatings is not limited to those stated above.

The painting robot 34 shown in Figure 2 sprays paint corresponding to each coating.

As shown in Figure 1, the painting system 1, in addition to the above configuration, includes a plurality of switching mechanisms 10 and a control device 20. Each of the plurality of switching mechanisms 10 is located at the branching point Pa, the connection point Pb, and each of the points from the first point PO1 to the eighth point PO8.

The management device 20 is configured as a computer comprising a processor and communication unit (not shown), and a storage unit 22. The storage unit 22 stores painting information 24. The management device 20 is configured to communicate with the switching mechanism 10 and the acquisition unit 12 (Figure 2).

As shown in Figure 4, the paint information 24 is information that associates the vehicle identification number, vehicle type information, the color information of the first base coat, and the color information of the second base coat. In addition, the paint information 24 also includes information such as whether or not it is a two-tone paint scheme, and, in the case of the third vehicle type, whether the two layers are the undercoat or the clear coat.

The switching mechanism 10 shown in Figure 1 is configured to communicate with the management device 20. The switching mechanism 10, located at the branching point Pa, uses the vehicle number acquired by the acquisition unit 12 and the paint information 24 to switch the destination of the vehicle body CB to either the first transport line C1 or the second transport line C2. Specifically, the management device 20 refers to the paint information 24 and determines whether the vehicle number acquired by the acquisition unit 12 upstream of the branching point Pa is for the first vehicle type. If it determines that it is for the first vehicle type, the management device 20 transmits a control signal to the switching mechanism 10 to switch the destination of the vehicle body CB to the second transport line C2. As a result, the switching mechanism 10 switches the destination of the vehicle body CB to the second transport line C2. On the other hand, if it determines that it is not for the first vehicle type, the management device 20 transmits a control signal to the switching mechanism 10 to switch the destination of the vehicle body CB to the first transport line C1. As a result, the switching mechanism 10 switches the destination of the vehicle body CB to the first transport line C1. Note that if the same vehicle type is transported continuously and the destination is the same, the switching operation of the switching mechanism 10 is omitted. The switching mechanisms 10 located at connection point Pb and at each point from the first point PO1 to the eighth point PO8 have the same configuration as the switching mechanism 10 located at branching point Pa, and therefore their explanation is omitted.

A2. Painting process:
Figure 5 is a flowchart showing the painting process for the second vehicle model. As shown in Figure 5, in step P10, electrodeposition coating is performed on the vehicle body CB, which is made by processing steel plates. Specifically, after pretreatment such as cleaning of the vehicle body CB, the vehicle body CB is immersed in an electrodeposition liquid tank containing electrodeposition paint in the electrodeposition booth Be, and the electrodeposition paint adheres to the vehicle body CB. In step P12, the vehicle body CB with the electrodeposition paint adhered to it is heated in a drying oven Fe and baked. This hardens the electrodeposition paint and forms an electrodeposition coating film on the vehicle body CB. After that, auxiliary materials are attached to the ceiling, floor, etc. of the vehicle body CB. Steps P10 to P12 are performed in the electrodeposition coating area Ae.

In the next step, the exterior and interior panels of the vehicle body (CB) will be painted with an undercoat. Here, the exterior panels refer to the parts of the vehicle body that are exposed to the outside when the doors, hood, and other opening parts are closed. The interior panels refer to the parts of the vehicle body that are not exposed to the outside when the opening parts are closed, but are exposed to the outside when the opening parts are open. Specifically, the interior panels of the vehicle body include pillars such as the center pillar.

In step P14, the inner panel of the vehicle body CB is coated with an intermediate coat. In step P16, the outer panel of the vehicle body CB is coated with an intermediate coat. The paint used for the intermediate coat can be a solvent-based paint or a water-based paint containing a synthetic resin, a hardener, and an organic solvent or water as a diluent. Steps P14 and P16 are performed in the first paint booth B1 shown in Figure 1. In step P18, the vehicle body CB with the intermediate coat applied is heated and baked in the drying oven F1. This hardens the intermediate coat, forming an intermediate coat film on top of the electrodeposited coating. Steps P14 to P18 are performed in the first painting area A1.

In the first forming step P20, the outer panel of the vehicle body CB is coated with a first base coat. In the second forming step P22, the inner panel of the vehicle body CB is coated with a second base coat. In the third forming step P24, the outer panel of the vehicle body CB is coated with a second base coat. The paint used for the first and second base coats can be a solvent-based paint or a water-based paint containing a pigment, a synthetic resin, a hardener, and an organic solvent or water as a diluent. In this embodiment, a water-based paint is used for the first and second base coats. The first forming step P20 to the third forming step P24 are performed in the upstream second painting booth B2a. In this embodiment, painting robots 34 corresponding to the first forming step P20, the second forming step P22, and the third forming step P24 are lined up along the first transport line C1. Each step is performed as the vehicle body CB is transported along the first transport line C1.

By applying a first base coat to the outer panel of the vehicle body CB, and then applying a second base coat to the inner panel of the vehicle body CB, the deterioration of the aesthetic appearance of the inner panel of the vehicle body CB can be suppressed. If the second base coat is applied to the inner panel before the first base coat is applied to the outer panel, the first base coat may adhere to the second base coat on the inner panel. This is because paint can seep into the inner panel through gaps, even when the opening and closing parts are closed. In this respect, according to this embodiment, even if the first base coat adheres to the inner panel in the first forming step P20, the second base coat is applied over the first base coat in the second forming step P22. Therefore, the first base coat is concealed by the second base coat, thus suppressing the deterioration of aesthetic appearance. It is also conceivable that the deterioration of aesthetic appearance when the first base coat adheres to the second base coat applied to the inner panel can be suppressed by making the color of the first base coat and the second base coat the same. However, in this case, it becomes necessary to prepare both the first base coat and the second base coat, which have a wider range of colors, potentially increasing manufacturing costs. Furthermore, because the components of the first base coat and the second base coat are different, it may be difficult to make the color of the first base coat identical to that of the second base coat.

In step P26 of Figure 5, the material is heated in the PH furnace F2. This step is also called preheating. Heating causes the diluent, specifically water, of the paint applied in steps P20 through P24 to the first forming step to evaporate. This increases the viscosity of the applied paint, improving the finish of the coating.

In step P28, a clear coat is applied to the outer panel of the vehicle body CB. The clear coat can be a solvent-based paint or a water-based paint containing a synthetic resin, a hardener, and an organic solvent or water as a diluent. Step P28 is performed in the downstream second paint booth B2b shown in Figure 1.

In step P30 of Figure 5, the vehicle body CB, to which the first base coat, second base coat, and clear coat have been applied, is heated in the drying oven F3 and baked. This hardens the first base coat, second base coat, and clear coat, forming a three-layer coating on top of the intermediate coat: the first base coat, the second base coat, and the clear coat. After step P30 is completed, this painting process is finished. The vehicle body CB is then transported to the area where the next process takes place. Steps P20 to P30 are performed in the second painting area A2.

The painting system 1 according to this embodiment is designed to paint not only the second vehicle model, but also the first and third vehicle models, whose paint film configurations differ from those of the second vehicle model. Specifically, the painting system 1 includes a second transport line C2, a third transport line C3, and a fourth transport line C4, which branch off from the first transport line C1.

As described above, the coating structure of the first vehicle model reduces the intermediate coating compared to the coating structure of the second vehicle model. Therefore, if the first vehicle model were to be painted using a painting system 1 without a second transport line C2, it would have to pass through the first painting area A1, resulting in unnecessary intermediate coating. In this respect, according to this embodiment, the vehicle body CB of the first vehicle model can be transported to the second painting area A2 without passing through the first painting area A1 by using the second transport line C2. Therefore, the production lead time, which is the time required from the start to the end of production per vehicle body CB, can be optimized. Furthermore, according to this embodiment, manufacturing costs such as processing costs and processing time related to the first vehicle model can be optimized.

The coating structure of the third vehicle type differs from that of the second vehicle type in that it has two layers of either an intermediate coating or a clear coating. For the third vehicle type with two layers of intermediate coating, efficient painting can be achieved by using the third transport line C3. For the third vehicle type with two layers of clear coating, efficient painting can be achieved by using the fourth transport line C4.

In the third vehicle model, two layers of paint, either an intermediate coat or a clear coat, are formed primarily to further enhance the vehicle's aesthetic appearance. In this embodiment, the painting of the two-layer paint film is performed in the first painting area A1, thereby optimizing the production capacity of both the first painting area A1 and the second painting area A2.

To explain in more detail, in a configuration of the painting system 1 different from this embodiment, it is conceivable that the fourth transport line C4 is connected to the upstream side of the second painting booth B2b downstream of the second painting area A2 where the clear coating is formed, in order to paint a third vehicle model in which two layers of clear coating are formed. However, in this configuration, it becomes necessary to provide surplus production capacity to the upstream second painting booth B2a in accordance with the production capacity of the downstream second painting booth B2b for the third vehicle model in which two layers of clear coating are formed. In this embodiment, however, the coating from the first base coating to the clear coating, which is common to the first to third vehicle models, is performed in the second painting area A2, while the coating that is not common to the first to third vehicle models is performed in the first painting area A1. As a result, there is no need to provide branching or merging points in the first transport line C1 of the second painting area A2, so that the painting system 1 can be made compact while efficiently performing painting in the second painting area A2.

Figure 6 is a table summarizing the transport routes in the painting system 1 for the first to third vehicle models. As shown in Figure 6, the vehicle body CB for the first vehicle model is transported by the first transport line C1 and the second transport line C2. Since the first transport line C1 is linked to each step of the painting process, the vehicle body CB for the first vehicle model skips steps P14 to P18 shown in Figure 5. As a result, the vehicle body CB for the first vehicle model forms a paint film with a paint film structure without an intermediate coat, as shown in Figure 3.

As shown in Figure 6 for the "double intermediate coat" of the third vehicle model, the vehicle body CB of the third vehicle model with the "double intermediate coat" is transported by the first transport line C1 and the third transport line C3. This causes the processes from P14 to P18 shown in Figure 5 to be repeated after process P18. As a result, the vehicle body CB of the third vehicle model with the "double intermediate coat" forms a coating with a two-layer intermediate coating, as shown in Figure 3. Note that the paint used for the first and second intermediate coatings may be the same or different.

As shown in Figure 6 for the third vehicle model "W Clear," the vehicle body CB of the third vehicle model "W Clear" is transported by the first transport line C1, the fourth transport line C4, and the sixth transport line C6. As a result, after step P30 shown in Figure 5, a clear coating is formed in the first painting area A1. Specifically, after clear coating is performed in the first painting booth B1 in the same manner as in step P28, baking is performed in the drying oven F1 in the same manner as in step P30.

In this embodiment, when the vehicle body CB of the third vehicle model, "W Clear," passes through the first paint booth B1 for the second time, the paint used in the painting process in the first paint booth B1 in the first painting area A1 is switched from the intermediate coat paint to the clear coat paint and sprayed onto the vehicle body CB. In other words, the first paint booth B1 is capable of performing both the intermediate coat and the clear coat, and is configured to form either an intermediate coat film or a clear coat film on the passing vehicle body CB. This allows the first paint booth B1 to be made more compact compared to a configuration that includes separate painting robots 34 for the intermediate coat and for the clear coat.

By passing through the first paint booth B1 again, the "W Clear" body CB of the third vehicle model is coated with two layers of clear paint, as shown in Figure 3. The paint used for the first and second layers of clear coating may be the same or different. After passing through the first painting area A1 for the second time, the "W Clear" body CB of the third vehicle model is transported using the sixth transport line C6 and proceeds to the next painting process without passing through the second painting area A2.

The fifth transport line C5 is used for painting the two-tone body CB. Figure 6 shows the transport route when two-tone painting is applied to the body CB of the second vehicle type. After process P30 shown in Figure 5, the process from the first forming process P20 to process P30 is repeated for the two-tone body CB. Two-tone painting is achieved by making the parts of the body CB painted the first time different from the parts painted the second time. In the second painting in the second painting area A2, the second forming process P22 may be omitted depending on the part of the body CB being painted. Two-tone painting can be applied not only to the second vehicle type but also to the first and third vehicle types by using the fifth transport line C5. Furthermore, the fifth transport line C5 is used not only for painting two-tone body CBs but also, for example, when there is a problem with the painting in the second painting area A2. Specifically, if a defect is detected during the painting inspection conducted after process P30, the affected vehicle body CB is transported to point 6 PO6 using the fifth transport line C5, and the processes from the first forming process P20 to process P30 are repeated in the second painting area A2.

According to the embodiment described above, the painting system 1 comprises a first transport line C1 and a second transport line C2. The first transport line C1 passes through the first paint booth B1 and the second paint booth B2. The second transport line C2 connects to the first transport line C1 at a connection point Pb on the first transport line C1 without passing through the first paint booth B1. This allows for the formation of a second base coat from an intermediate coat using the first transport line C1, and the formation of both the first and second base coats without forming an intermediate coat using the second transport line C2. Therefore, painting of different vehicle types can be easily performed.

Furthermore, the second transport line C2 branches off from branching point Pa, located between the electrodeposition booth Be and the first painting booth B1, and merges with the first transport line C1 at connection point Pb. As a result, the vehicle body CB is transported using the first transport line C1 up to branching point Pa, allowing the same electrodeposition booth Be to be used regardless of the vehicle type.

Furthermore, the painting system 1 comprises an acquisition unit 12, a storage unit 22 for storing painting information 24, and a switching mechanism 10. The switching mechanism 10 uses the identifier acquired by the acquisition unit 12 and the painting information 24 to switch the destination of the vehicle body CB. Therefore, the switching mechanism 10 can automatically switch the destination of the vehicle body CB according to the vehicle type.

Furthermore, the first paint booth B1 is located upstream of the second paint booth B2 and is capable of forming a single layer of intermediate coating. The second paint booth B2 is capable of forming a single layer of first base coating. This allows the vehicle body CB to be transported to the first transport line C1, where the intermediate coating and first base coating can be formed sequentially. Additionally, the first paint booth B1 is configured to form either a single layer of intermediate coating or a single layer of clear coating on the passing vehicle body CB. This allows the painting of a third vehicle type with two layers of clear coating to be performed using the first paint booth B1, optimizing the production capacity of the second paint booth B2 and enabling efficient painting processes.

Furthermore, in the second paint booth B2, the following steps are performed in this order: a first forming step P20 to form a first base coat on the outer panel of the vehicle body CB, a second forming step P22 to form a second base coat on the inner panel of the vehicle body CB, and a third forming step P24 to form a second base coat on the outer panel of the vehicle body CB. As a result, even if the first base coat adheres to the inner panel of the vehicle body CB during the first forming step P20, the second base coat will be applied to the inner panel during the subsequent second forming step P22. Therefore, the first base coat is concealed by the second base coat, thus preventing a deterioration in the vehicle's aesthetic appearance.

Furthermore, the painting system 1 includes a third transport line C3 that branches off from the first point PO1 on the first transport line C1 and merges with the second point PO2 on the first transport line C1. Therefore, by using the third transport line C3, a third vehicle type with two layers of intermediate paint can be efficiently painted. The painting system 1 also includes a fourth transport line C4 that branches off from the third point PO3 on the first transport line C1 and merges with the fourth point PO4 on the first transport line C1. Therefore, by using the fourth transport line C4, a third vehicle type with two layers of clear paint can be efficiently painted. Furthermore, the painting system 1 includes a fifth transport line C5 that branches off from the fifth point PO5 on the first transport line C1 and merges with the sixth point PO6 on the first transport line C1. Therefore, by using the fifth transport line C5, a two-tone vehicle body CB with two different body colors can be efficiently painted.

Furthermore, the painting system 1 comprises a first painting booth B1, a second painting booth B2, a first transport line C1, and a second transport line C2. The first painting booth B1 forms the intermediate coating and the second clear coating, which are coatings other than the common coating used for multiple vehicle types (from the first to the third vehicle types). The second painting booth B2 forms the coatings common to multiple vehicle types, from the first base coating to the first clear coating. The first transport line C1 passes through both the first and second painting booths B1 and B2. The second transport line C2 connects to the first transport line C1 at connection point Pb without passing through the first painting booth B1. This allows for the formation of a common coating for multiple vehicle types by passing all vehicle bodies CB through the second painting booth B2, regardless of the vehicle type. Furthermore, by using the first painting booth B1 to apply the coatings other than the common coating for multiple vehicle types, painting of different vehicle types can be easily performed.

Furthermore, the first paint booth B1 is configured to apply an intermediate coating, which is a coating other than the common coating, for multiple vehicle models. The second paint booth B2 is configured to apply a first base coating and a second base coating, which are common coatings. Therefore, for the vehicle body CB of the first vehicle model, the first base coating and the second base coating can be formed using the second transport line C2 without forming an intermediate coating. For the vehicle body CB of the second vehicle model, the intermediate coating, the first base coating, and the second base coating can be formed sequentially on the vehicle body CB. Additionally, the first paint booth B1 is configured to form either a single-layer intermediate coating or a single-layer clear coating on the passing vehicle body CB. This allows the third vehicle model, which has two layers of clear coating, to be painted using the first paint booth B1, and optimizes the production capacity of the second paint booth B2, enabling efficient painting processes by the painting system 1.

B. Other embodiments:
(B1) In the above embodiment, the second transport line C2 branches off from the first transport line C1 at branching point Pa. In other embodiments, (a) the upstream end of the second transport line C2 may not branch off from the first transport line C1, and the downstream end of the second transport line C2 may merge with the first transport line C1 at connection point Pb, and (b) the upstream end of the second transport line C2 may branch off from the first transport line C1 at connection point Pb, and the downstream end of the second transport line C2 may not merge with the first transport line C1. At least, by having the second transport line C2 not pass through the first paint booth B1, the body CBs of multiple vehicle types can be easily painted. Also, in the above embodiment, branching point Pa is located between the electrodeposition booth Be and the first paint booth B1, but it may be located upstream of the electrodeposition booth Be.

(B2) In the above embodiment, the first painting area A1 is located upstream of the second painting area A2. In another embodiment, the first painting area A1 may be located downstream of the second painting area A2. In the paint film configuration of multiple vehicle models, the arrangement order of the first painting area A1 and the second painting area A2 should be determined by the painting order of the common paint film and the other paint films. That is, if there are no vehicle models with paint films other than the common paint film between the common paint film and the electrodeposited paint film, the second painting area A2 should be located upstream of the first painting area A1.

(B3) In the above embodiment, the branching point Pa, the fourth point PO4, and the second point PO2 are arranged in this order from upstream to downstream on the first conveyor line C1, but the arrangement order of each point is not limited to this order. Furthermore, multiple points may be provided at the same location. Specifically, the branching point Pa and the fourth point PO4 may be provided at the same location and implemented by a single switching mechanism 10. Also, a portion of multiple conveyor lines C may be implemented by a common conveyor. Specifically, a portion of the upstream side of the third conveyor line C3 and the fourth conveyor line C4 may be implemented by a common conveyor.

(B4) In the above embodiment, the first painting booth B1 is configured to form either an intermediate coating or a clear coating on the passing vehicle body CB by switching the paint supplied to the painting robot 34. In another embodiment, the first painting booth B1 may be configured to form either an intermediate coating or a clear coating on the passing vehicle body CB by arranging a painting robot 34 for intermediate coating and a painting robot 34 for clear coating along the first transport line C1 and having them paint selectively.

(B5) In the above embodiment, the vehicle bodies CB of the first, second, and third vehicle models are painted. The vehicle models and their paint film configurations painted by the painting system 1 are not limited to those described above. The painting system 1 can also paint vehicle models in which, for example, three or more clear coating layers are formed.

(B6) In the above embodiment, the painting system 1 includes an electrodeposition area Ae before the first painting area A1. In other embodiments, the painting system 1 may not include an electrodeposition area Ae. This is because the electrodeposition coating can be omitted when the vehicle body CB is made of resin rather than metal. In this case, the vehicle body CB is transported from the pre-painting process to the first painting area A1. Then, a first base coating or an intermediate coating is formed on the vehicle body CB.

This disclosure is not limited to the embodiments described above, and can be implemented in various configurations without departing from its spirit. For example, the technical features of the embodiments corresponding to the technical features in each form described in the summary of the invention can be replaced or combined as appropriate to solve some or all of the above-described problems, or to achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate.

1...Painting system, 10...Switching mechanism, 12...Acquisition unit, 20...Management device, 22...Storage unit, 24...Painting information, 32...Partition wall, 36...Support member, 38...IC tag, A1...First painting area, A2...Second painting area, Ae...Electrodeposition painting area, B1...First painting booth, B2...Second painting booth, B2a...Upstream second painting booth, B2b...Downstream second painting booth, Be...Electrodeposition booth, C...Conveyor line, C1...First conveyor line, C2...Second conveyor line, C 3…Third conveyor line, C4…Fourth conveyor line, C5…Fifth conveyor line, C6…Sixth conveyor line, CB…Vehicle body, F1, F3…Drying oven, F2…PH oven, P10, P12, P14, P16, P18, P26, P28, P30…Process, P20…First forming process, P22…Second forming process, P24…Third forming process, PO1…First point, PO2…Second point, PO3…Third point, PO4…Fourth point, PO5…Fifth point, PO6…Sixth point, Pa…Branching point, Pb…Connection point

Claims (8)

A painting system that performs painting,
A first paint booth for forming the first paint film layer on the vehicle body,
A second paint booth for forming a second paint layer different from the first paint layer on the vehicle body,
A first conveying line that supports the vehicle body and conveys it in the conveying direction, the first conveying line passing through the first paint booth and the second paint booth,
A second transport line that supports the vehicle body and transports it in the transport direction, comprising a second transport line that does not pass through the first paint booth but connects to the first transport line at a connection point on the first transport line between the first paint booth and the second paint booth ,
The first coating layer includes the first coating,
The second coating layer comprises at least a second coating and a third coating,
The second coating and the third coating are colored, and the second coating and the third coating are different in color from each other.
In the aforementioned second paint booth,
A first forming step of forming the second coating on the outer panel of the vehicle body,
A second forming step involves forming the third coating on the inner panel portion of the vehicle body,
A painting system comprising the steps of: a third forming step of forming the third coating film on the outer panel portion, and the following steps, in this order . A painting system according to claim 1,
The first paint booth is located upstream of the second paint booth.
The painting system further comprises an electrodeposition booth for performing electrodeposition painting on the upstream side of the first painting booth on the first transport line,
The second transport line is a painting system that branches off from a branching point on the first transport line located between the electrodeposition booth and the first painting booth. The coating system according to claim 2, further,
An acquisition unit that acquires an identifier pre-assigned to the vehicle body,
A storage unit that stores painting information in which the identifier and the coating configuration composed of multiple coating films are pre-associated,
The vehicle body is transported to either the first transport line or the second transport line, and is provided with a switching mechanism located at the aforementioned branching point.
The aforementioned switching mechanism is
A painting system that switches the transport destination using the identifier and painting information acquired by the acquisition unit. A painting system according to claim 1,
The aforementioned vehicle body has multiple vehicle types, each having a different coating configuration composed of multiple coating films .
The aforementioned multiple vehicle models are
The coating structure of the first vehicle model does not include the first coating film, but includes at least a single layer of the second coating film,
The coating configuration includes a second vehicle model comprising at least a single layer of the first coating and a single layer of the second coating,
The first paint booth is located upstream of the second paint booth and is configured to form a single layer of the first paint film.
The painting system is configured such that the second painting booth is capable of forming a single layer of the second coating film. A coating system according to claim 4,
The aforementioned second coating layer further includes a fourth coating layer ,
The first vehicle model further includes a single layer of the third coating and a single layer of the fourth coating in its coating structure.
The second vehicle model further includes a single layer of the third coating and a single layer of the fourth coating in its coating structure.
The aforementioned multiple vehicle models are further,
The coating structure includes at least a single layer of the first coating, a single layer of the second coating, a single layer of the third coating, and a single layer of the fourth coating, and includes a third vehicle model in which at least one of the first coating and the fourth coating is a multi-layer structure.
The aforementioned first paint booth is
A painting system configured to form either a single layer of the first coating or a single layer of the fourth coating on the vehicle body as it passes over it. A painting system according to claim 1,
The first paint booth is located upstream of the second paint booth.
A painting system comprising a third transport line that supports the vehicle body and transports it in the opposite direction to the transport direction, the third transport line further branching off from a first point on the first transport line between the first paint booth and the second paint booth and merging at a second point on the first transport line upstream of the first paint booth. A painting system according to claim 6 ,
A painting system comprising a fourth transport line that supports the vehicle body and transports it in the opposite direction to the transport direction, the fourth transport line further branching off from a third point downstream of the second paint booth on the first transport line and merging at a fourth point upstream of the first paint booth on the first transport line. A coating system according to claim 7 ,
A painting system comprising a fifth transport line that supports the vehicle body and transports it in the opposite direction to the transport direction, the fifth transport line branching off from a fifth point downstream of the second paint booth on the first transport line and merging at a sixth point on the first transport line between the first paint booth and the second paint booth.