JPH0443995B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a new electrodeposition coating device, and more specifically, a new type of electrodeposition coating device that improves the conventional batch type device and slipper dip type device. This invention relates to an electrodeposition coating device.

(Prior Art) Conventional electrodeposition coating apparatuses are broadly classified into batch type and slipper dip type.

FIG. 6 shows a batch-type electrocoating apparatus conventionally used for electrocoating automobile parts (having a length of just over 1 m). This device includes a side electrode 2a and a bottom electrode 2b together with a protection plate 22, an agitation riser 23, etc. in an electrocoating paint tank 20 with a length of 3 to 5 m, and a drop lifter 21 in the paint tank 20.
The lifter 2 is installed so that it can be raised and lowered above the
A power supply 25 and an electrode 2 above the paint tank 20 to which the collector 24 attached to the electrode 2 can be connected and separated.
a and 2b are connected to a power source 26. Then, as shown in FIG. 7, by operating the drop lifter 21, the object to be coated 10 suspended from the hanger 27 is first carried from a remote location to above the electrodeposition paint tank 20 and kept at rest (position). Next, it is lowered and immersed in the paint tank 20 (position), and after electrocoating is performed by applying electricity between the power supply, the current collector, the hanger, and the electrodes of the object to be coated, the object to be coated 10 is raised and immersed in the paint tank 20. Electrodeposition coating is carried out by the operation procedure of lifting it above 20, keeping it at rest (position), and then carrying it away.

Further, FIG. 9 shows a conventional slipper dip type electrodeposition coating apparatus used for electrodeposition coating of automobile parts similar to the above.

This device is equipped with an electrode 29, a protective wire mesh 30, a stirring riser 31, etc. on the inner side (not shown) and the bottom of an electrodeposition paint tank 28 with a length of more than ten meters, and above the paint tank 28. Power supply rail (power supply)
32 is provided along the longitudinal direction of the paint tank 28, and the electrode 29 and the power supply rail 32 are each connected to a DC power source 33. Furthermore, a transport conveyor 34 is provided above the paint tank 28 along its longitudinal direction, and sequentially transports a plurality of objects to be painted 10, 10, 10, etc. suspended from a hanger 35 into the paint tank 28. It is designed to be continuously transported from the tank section to the fully energized area and to the outlet section. Further, the hanger 35 is in contact with the power supply rail 32 and is connected to the objects 10, 10, 10, . . . to be coated via the hanger 35.
collector 36 and hanger 35 for energizing
An insulator 37 is attached to insulate the transport conveyor 34 from the transport conveyor 34. The article 10 to be coated, which has been conveyed by the conveyor 34 and dipped into the paint in the tank from the input part of the paint tank 28, is transferred to the hanger 3.
From the moment the collector 36 attached to the tank 5 comes into contact with the power supply rail 32, energization starts and electrodeposition coating begins, and in the process of being transferred from the inlet part to the fully energized area and to the outlet part. The article 10 to be coated, which has been electrodeposited to a predetermined coating thickness and has been coated, is carried out of the tank from the tank outlet section.

(Problems to be Solved by the Invention) This electrodeposition coating is generally performed under the conditions of a paint concentration of about 20%, a paint temperature of about 25°C, and a DC voltage of 250 to 300 V, especially about 280 V. In order to form a coating film on the surface of the object to be painted, for example, a charging voltage of 280V and a total energization time of about 180 seconds (the total time during which the object is energized while it is in the paint liquid) are required. . Also, the first 10 seconds of the total energization time is required as a so-called soft start, a stage in which the charging voltage is raised to a predetermined voltage to prevent roughening of the painted surface.

Therefore, when a batch type electrodeposition coating apparatus as shown in FIGS. 6 and 7 is used, the coating process has conventionally been carried out according to the time chart shown in FIG. 8. In this case, the operation time of the drop lifter 21, such as horizontal travel and lifting and lowering, is added to the above-mentioned total energization time, resulting in a long takt time of approximately 260 seconds (from the start of processing of one workpiece to the start of processing of the next workpiece). (time required to start processing the product).

On the other hand, when using a slipper dip type electrodeposition coating apparatus as shown in FIG.
The painting process was carried out according to the time chart shown in Figure 0.

In this case, first, the first article 10 to be coated is placed in the paint tank 2.
8 and completely immersed in the bath, electricity is started to perform electrodeposition coating, and then, just before the next article to be coated 10 is placed in the tank, the electricity is cut off once, and the next article to be coated 10 is
After the paint was completely immersed in the paint tank 28, electricity was turned on again, and the electrodeposition coating progressed until the specified coating thickness was reached (total immersion time of 180 seconds/280V), and the painting was completed. The article 10 to be coated is automatically and continuously carried out of the tank by a conveyor and transferred to the next process. By the way, in the example shown in Figure 10, the takt time was 120 seconds, but by shortening the hanger pitch (conveyor pitch) between one item to be coated and the next item to be coated, the tact time can be further shortened. can do.

That is, the slipper-dip type electrodeposition coating apparatus has an extremely short takt time and a very high processing efficiency, and is more advantageous than the batch type in this respect.

However, patch-type electrocoating equipment requires only a small paint tank, so the installation space is small and equipment costs are low, whereas slipper dip-type electrocoating equipment requires a very long paint tank. Therefore, a very large installation space and high equipment cost are required. Therefore, the batch type electrodeposition coating apparatus is more advantageous than the slipper dip type in terms of installation space and the like.

The present invention has been made in consideration of the above-mentioned circumstances, and is a completely new electrical appliance that has a takt time as short as that of the slipper dip type and requires less installation space than the batch type. The present invention provides a coating device.

(Means for Solving the Problems) The electrodeposition coating apparatus of the present invention has a structure in which the paint tank is composed of three zones, each zone is equipped with an electrode and a power supply, and each zone is energized by two power sources. This makes it possible to process two or more objects at the same time. That is, the apparatus of the present invention includes: an electrodeposition paint bath consisting of three sections: an entry area, a fully energized area, and an exit area; electrodes provided inside the bath in each of the areas; and each of the areas. A first power supply connected to the electrode and power supply in the tank entry area, a first power supply connected to the electrode and power supply in the fully submerged area, and an electrode and power supply in the exit area, respectively. The connected second power source and the lifter can be moved up and down vertically and horizontally, and when moving from the tank entry area to the fully energized area and from the fully energized area to the exit area, the current collector returns to its original state. In order to be able to connect simultaneously to the power supply in one area and the power supply in the next area, the product to be coated enters the tank area from outside the tank, and then, while completely immersed, it is connected from the tank area to the fully energized area. The device is characterized by having a transfer mechanism for transporting it from the fully energized area to the tank outlet area, and then pulling it out of the tank from the outlet area.

(Function) In the electrodeposition coating apparatus of the present invention, by operating the transfer mechanism, the article to be coated first enters the entry area of the paint tank from outside the tank, is then transported to the fully energized area, and then exits the tank. When in each of these areas, electricity is passed between the electrode, the object to be coated, the current collector, and the power supply to perform electrodeposition coating, and then the object is lifted out of the tank and transported to the next process. Electrodeposition coating in this case is energized separately from two power sources, but as in the case of the slipper dip type, it is continuously energized across the bath entry area, fully energized area, and exit area. It is carried out as

Therefore, when using the device of the present invention, for example,
While one object A is being painted in the fully energized area of the paint tank, another object B is put into the inlet area of the paint tank, and the object A is placed outside the tank. By repeating the operation procedure of transporting the workpiece B to the fully energized area of the paint tank and then lifting the workpiece A out of the tank, two workpieces can be treated at the same time. Can be done. Further, by making it possible to accommodate two or more objects to be coated in the fully energized area, three or more objects to be coated can be processed at the same time. Therefore, the takt time can be significantly shortened compared to a batch type electrodeposition coating apparatus.

In addition, the electrodeposition coating apparatus of the present invention only requires that the paint tank has a capacity for the area that can accommodate the object to be coated, and therefore requires less installation space than a slipper dip type electrodeposition coating apparatus. Can be made significantly smaller.

In addition, in the apparatus of the present invention, in order to enable the above-mentioned series of energization, the power feeder is normally used to connect the current collector of the lifter that supports the object to be coated when moving the object to be coated from one area to the next area. is arranged so that it is temporarily connected to the power supply of the original area and the power supply of the next area at the same time.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the electrodeposition coating apparatus of the embodiment includes an electrodeposition paint tank 1 having a total length of 5 to 7 m and consisting of three areas: an entry area, a fully energized area, and an exit area. , electrodes 2, 2, 2 are provided for each area of the paint tank 1 on both sides of the tank (one side is not shown) and the bottom of the tank (not shown), and power feeders (power feed rails) 3, 3 are provided. , 3 are installed above the tank for each area of the paint tank 1. The electrode 2 in the tank entry area is connected to the negative pole of the first power source 4 via the distribution board 6 and the disconnector 19, and the electrodes 2 in the fully energized area and the tank exit area are connected to the distribution board 6 and Disconnector 19
The power supply 3 in the tank entry area is connected to the positive terminal of the first power supply 4 through the disconnector 19, and the power supply 3 in the tank entry area is connected to the positive terminal of the first power supply 4 through the disconnector 19. The power feeders 3, 3 are connected to the positive electrode of the second power source 5 via a disconnector 19, respectively. Each power source 4, 5 converts AC electricity from a main power source (not shown) into DC electricity with a voltage of 350V and a current of 650A. The disconnector 19 is used to cut off the influence of the other power source from being transmitted to the failed power source when one power source fails. The distribution boards 6, 6 are connected via a short circuit board 7, so that when one breaks down, it is short-circuited and can be temporarily used as the other board. Furthermore, wiring from the first power source 4 to the power feeder 3 in the tank area, wiring from the second power source 5 to the power feeder 3 in the fully energized area, and the second power source 5
The wiring to the power feeder 3 in the outlet area can be connected and disconnected by DC interrupters 8 and 9, respectively, as shown in the figure.

This means that when each article 10 to be coated moves from the entry tank area to the fully energized area and from the fully energized area to the exit area,
To prevent sparks from occurring due to voltage difference when the same current collector contacts two power feeders 3, 3 at the same time, the two power feeders 3, 3 are connected to the same voltage by connecting them in advance with a DC interrupter 8. It is intended to be kept as is.

Further, as shown in FIGS. 4 and 5, the electrodeposition coating apparatus of the embodiment is equipped with a lifter 9 above the paint tank 1 that horizontally runs or moves up and down while supporting the article 10 to be coated. The lifter 9 includes a pedestal 12 that can be moved up and down, and from this pedestal 12, a support frame 14 on which an article to be coated 10 is mounted is swingably suspended via an insulator 13. Reference numeral 15 denotes a swing cylinder for swinging the support frame 14 at an angle of approximately ±20. Further, 16 is a protection net, 17 is an agitation riser, and 18 is a protection frame.

Furthermore, the device of the embodiment has two current collectors 11 for each support frame 14 near the insulators 13;
In addition, when moving the product to be coated from one area to the next (for example, from the tank area to the fully immersed area), the power supply in the original area and the power supply in the next area can be connected at the same time, albeit temporarily. It will be placed.

Thus, the electrodeposition coating process using this apparatus is performed, for example, in the following procedure. As shown in FIG. 2, by operating the transfer mechanism including the lifter 9, the first article to be coated 10 is first transported (positioned) from the previous process to the upper part of the entry area of the electrodeposition paint tank 1, and then it is transported. It is lowered and immersed in the paint tank 1 (position), and then electricity is started via the first power source 4. Next, in Figure 1, after activating the DC interrupter 8 on the left side and connecting the power supply 3 in the tank entry area and the power supply 3 in the fully energized area to the same voltage, the article 10 to be coated is completely It is transferred (position) from the immersed tank area to the fully energized area while remaining submerged, and when the transfer is completed, the DC interrupter 8 is deactivated and the connection between the power feeders 3 and 3 is cut off. During this time, the power supply device 3 in the fully energized region continues to be energized with a charging voltage of 300V via the second power source 5. At the same time, when the article 10 to be coated is in the fully energized region, the next article 10 to be coated is carried to the upper part of the entry area of the paint tank 1 (position), then penetrated into the paint tank 1 (position), and then Electricity is started via the first power source 4. After that, both DC interrupters 8 are activated to connect all the power feeders 3 in each area to the same voltage, and while continuing to energize the article 10 to be coated, the area is changed from the fully energized area to the area where the tank comes out. At the same time (position), the next workpiece 10 to be coated is moved from the tank entry area to the fully energized area (position),
Thereafter, the operation of both DC interrupters 8 is stopped, and the article 10 to be coated is lifted out of the tank exit area (position) and carried away to the next process. Furthermore, when the next object to be coated 10 is located in the fully energized area,
The third article 10 to be coated is carried above the entry area of the paint tank 1 (position), then lowered to enter the tank 1 (position), and energization is started. After that, in the same manner as the previous time, the next workpiece 10 is moved to the discharge tank area (position), and at the same time the third workpiece 10 is moved to the fully energized area (position), and during this time the current is turned off to the previous workpiece. Continue as in case 10. Thereafter, the next article 10 to be coated is lifted out of the tank (position) and carried away to the next process. On the other hand, the fourth object to be painted 1
Has the arrival of 0. Thereafter, repeat the above steps.

When using the device of the example according to the above procedure,
The electrodeposition coating process could be carried out according to the time chart shown in FIG. 3, and a takt time of about 130 seconds was achieved. (Effects of the Invention) As described above, the electrodeposition coating apparatus of the present invention has the following features:
By adopting a structure that allows multiple objects to be coated to be coated at the same time by applying electricity from two power supplies in a paint tank consisting of three zones, the takt time can be significantly shortened, and the slipper It is possible to obtain the same level of coating processing efficiency as the dip-type device, and to make the installation space and equipment cost much smaller and lower than the batch-type device.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an electrodeposition coating apparatus according to an embodiment of the present invention, FIG.
Figure 4 is a cross-sectional view of the electrodeposition coating apparatus shown in Figure 1, and Figure 5 is a time chart of the electrodeposition coating apparatus used in the electrodeposition coating apparatus shown in Figure 1. A side view showing the transfer mechanism, FIG. 6 is a schematic diagram showing a conventional batch-type electrodeposition coating device, FIG. 7 is a diagram showing the transfer process of objects to be coated in a conventional batch-type electrodeposition coating device, and FIG. 8 9 is a diagram showing an electrodeposition coating time chart in a conventional batch type electrodeposition coating apparatus, FIG. FIG. 2 is a diagram showing an electrodeposition coating time chart in a conventional slipper dip type electrodeposition coating apparatus. In the figure, 1...electrodeposition paint tank, 2, 2a, 2b...
Electrode, 3... Power supply, 4... First power source, 5...
Second power supply, 9... Lifter, 10... Item to be painted,
11...Electron collector.

Claims (1)

[Scope of Claims] 1. An electrodeposition paint bath consisting of three areas: an entry area, a fully energized area, and an exit area; electrodes provided inside the tank in each of the areas; and an electrode in each of the areas. The power supply installed above the tank, the first power supply connected to the electrode and power supply in the tank entry area, the electrode and power supply in the fully immersed area, and the electrode and power supply in the tank exit area, respectively. The second power supply and the lifter can be moved up and down vertically and horizontally, and when moving from the tank entry area to the fully energized area and from the fully energized area to the exit area, the current collector returns to its original state. Prepare to be able to connect to the power supply in one area and the power supply in the next area at the same time, inject the product to be coated into the tank entry area from outside the tank, and then transfer it from the entry area to the fully energized area while remaining fully immersed. 1. An electrodeposition coating device comprising a transfer mechanism for transporting the device from the fully energized area to the outlet area, and then pulling it up from the outlet area to the outside of the tank.