JP2008138251A - Electrodeposition coating apparatus and electrodeposition coating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrodeposition coating apparatus and an electrodeposition coating method which are sufficiently applicable even to the increase of production quantity. <P>SOLUTION: The electrodeposition coating apparatus comprises an electrodeposition bath 10 having a removable partition wall 27 for sectioning it into a first bath 11 and a second bath 12, a circulator J for circulating electrodeposition paint in each bath, a conduction unit T having partition anodes 34, 35, and bare anodes 36, 37 provided on the inside of each bath and a cathode 38 provided on the outside of each bath and a power source, and a conveyance unit H for immersing a chassis W into any one bath. The cathode can be connected with the chassis immersed into any one bath or can be interrupted therefrom, and the chassis conveyed through the conveyance unit moves under immersed state across each bath thus united. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrodeposition coating apparatus and an electrodeposition coating method used for painting a vehicle such as an automobile.

  Conventionally, batch-type electrodeposition coating has been adopted in small-scale automobile production of 30,000 to 40,000 cars per year. In this batch-type electrodeposition coating, the vehicle body placed on the hanger of the transfer device from the upstream welding process on the upstream side is stopped on the electrodeposition tank, and then the hanger is lowered to electrify the vehicle body. It is immersed in the electrodeposition liquid in the deposition tank, energized for a predetermined time corresponding to the tact time, and the electrodeposition coating film is deposited on the vehicle body, and then the hanger is raised to the downstream process on the wake side by the conveying device. It is to be transported.

  In such a conventional electrodeposition coating, it is necessary to energize the vehicle body for 2 to 3 minutes in the electrodeposition tank in order to obtain the required film thickness of the electrodeposition coating film. When shifting to a medium-sized automobile production volume of 10,000 to 80,000 units, the current-carrying time is shortened as much as the tact time is shortened, so it cannot be handled as it is. Therefore, the equipment is changed from a batch type small electrodeposition tank to a large full-dip tank, and the so-called tact-type electrodeposition coating in which electricity is applied while moving the body in the electrodeposition liquid in the full-dip tank. There is a problem that the production facility becomes large.

On the other hand, two batch tanks are provided side by side, the vehicle body placed and transported on the hanger of the transport device from the previous welding process is stopped on the first batch tank, and then the hanger is lowered to the first batch. Immerse the car body in the electrodeposition liquid in the tank, energize for half of the predetermined time to deposit the electrodeposition coating on the car body, raise the hanger and stop the hanger on the second batch tank by the transport device Then, the hanger is lowered to immerse the vehicle body in the electrodeposition solution in the second batch tank, and the electrodeposition coating film is deposited on the vehicle body by energizing for half the predetermined time (patent) Reference 1).
Japanese Patent Laid-Open No. 10-025599

  However, in the above prior art, the body electrodeposited in the first batch tank is once taken out from the electrodeposition liquid in the first batch tank, transferred to the upper side of the second batch tank, and then in the second batch tank. Since the vehicle body is immersed in the electrodeposition liquid and electrodeposition coating is performed again, the time period from when the vehicle body is taken out from the electrodeposition liquid in the first batch tank and again immersed in the electrodeposition liquid in the second batch tank In this state, dust adheres to the electrodeposition coating film deposited on the vehicle body, and if the electrodeposition coating film is further deposited in the second batch tank in this state, dust is mixed into the electrodeposition coating film, resulting in poor electrodeposition. There's a problem.

  Accordingly, an object of the present invention is to provide an electrodeposition coating apparatus and an electrodeposition coating method that can be sufficiently adapted to an increase in production.

In order to achieve the above object, the invention described in claim 1 includes a plurality of electrodeposition tanks (for example, the electrodeposition tank 10 in the embodiment) via a partition wall (for example, the partition wall 27 in the embodiment) that can be attached and detached. A circulation device (for example, an embodiment) that can be partitioned into tanks (for example, the first tank 11 and the second tank 12 in the embodiment) and can be at least partially combined, and circulates the electrodeposition paint in each tank. In which the anode (for example, the partition anode plates 34 and 35 and the bare anode plates 36 and 37 in the embodiment) and the cathode (for example in the embodiment) provided on the outside are provided. An energizing device (for example, the energizing device T in the embodiment) provided with a cathode plate 38, 39) and a power source (for example, the power sources 60, 63 in the embodiment) is provided, and a conveying device (for example, conveying in the embodiment). The vehicle body (for example, the vehicle body W in the embodiment) conveyed through the device H) is configured so as to be immersed in any of the tanks, connected to the cathode, and configured to be cut off, and via the conveying device. It is characterized by being configured to be movable in a state where the transported vehicle body is immersed across the combined tank.
By configuring in this way, using any one of the divided tanks, the electrodeposition paint is circulated by the circulation device, and the vehicle body, which is a fixed time work corresponding to the tact time, is energized by the energization device. In the case of the production volume that can be immersed in one tank, the tact time is shortened because the production volume has increased, and the body is placed in the part of one tank before the coalescence of the tank that has been merged with the necessary partition walls removed. The amount of time for electrodeposition coating is calculated by adding the time to soak the body and the time to move from the part of the one tank to the part of the other tank that has been joined while the body is immersed, Therefore, it is possible to selectively use the production amount that needs to be secured as a time for the purpose.
Moreover, when performing electrodeposition coating using one of the tanks partitioned by the partition, maintenance such as cleaning can be performed on other unused tanks.

According to the second aspect of the present invention, the electrodeposition tank is partitioned into a first tank and a second tank via a removable partition, and an overflow tank (for example, an implementation) is provided in the first tank and the second tank. The overflow tanks 13 and 14) in the embodiment are provided, and the electrodeposition paint circulation is connected to each overflow tank through the first tank and the second tank via the pressure feeding device (for example, the pressure feeding device A in the embodiment). Pipes (for example, the pipes 15 and 16 in the embodiment), and nozzles that open in the first tank and the second tank (for example, the ejection nozzles 21 and 22 in the embodiment) at the ends of the pipes. ), A diaphragm anode plate is disposed on the inner walls of the first tank and the second tank, and a bare anode plate is disposed on the bottom wall, and these diaphragm anode plate and bare anode plate are used as anodes of the power source. Connect and above both side walls of the first tank and the second tank In addition, a cathode plate that can be rotated around a vertical axis and that can be moved up and down is provided, each cathode plate is connected to a cathode of a power source, and is configured to be movable along a transport rail (for example, the transport rail 46 in the embodiment). A hanger (for example, hanger 57 in the embodiment) that supports the vehicle body is provided on the carrier (for example, carrier 47 in the embodiment), and the hanger is provided so as to be movable up and down, and a current collector plate (for example, a collector in the embodiment) is provided. An electric plate 59) is provided, and the current collector plate can be connected to and cut off from the cathode plate by the lifting and lowering operation of the hanger.
By configuring in this way, using either the first tank or the second tank, while circulating the electrodeposition paint from the overflow tank into the first tank and the second tank through the pressure feeding device, piping, nozzle, The diaphragm anode plate and the bare anode plate are connected to the anode of the power source, and the current collector plate of the hanger that holds the work body is connected to the cathode plate connected to the cathode of the power source while energizing to meet the tact time In the case of a production volume that allows the vehicle body to be immersed for a certain period of time, and because the production volume has increased, the tact time has been shortened and the partition between the first tank and the second tank has been removed, Electrodeposition coating is the sum of the time to immerse the car body and the time to move from the first tank part to the second tank part in the electrodeposition tank while immersing the car body, and then to stay at the second tank part. As the time for production needs to be ensured and selective It can be selectively used to become.
Moreover, when performing electrodeposition coating using either the 1st tank or the 2nd tank, maintenance, such as cleaning of the tank which is not used, can be performed.

According to a third aspect of the present invention, the carrier is moved on the transport rail via a roller (for example, the roller 49 in the embodiment) by a servo motor (for example, the servo motor 48 in the embodiment) disposed on the carrier. It is characterized by moving.
By comprising in this way, the vehicle body which is a workpiece | work can be continuously conveyed with sufficient precision.

According to the fourth aspect of the present invention, a pair of suspension members (for example, the embodiment) that is moved up and down by a plurality of drive sources (for example, the motors 51 and 52 in the embodiment) disposed on the carrier below the carrier. , The hanger is attached to the tip of the suspension member, and the hanger is disposed on the lower surface of the carrier so as to be able to contact and separate.
By comprising in this way, it becomes possible to fix a hanger to a carrier by making a hanger contact | abut to the lower surface of a carrier.

  The invention described in claim 5 is an electrodeposition coating method applied to small-scale production to medium-scale production of automobiles, and in the case of small-scale production, it is divided into a plurality of tanks via removable partition walls. Electrodeposition coating was performed by immersing the vehicle body in any one of the formed tanks, and when the inner wall of the tank became dirty, the electrodeposition paint was transferred from the one tank to another tank and transferred. While immersing the vehicle body in another tank and continuing the electrodeposition coating, it was necessary to wash one tank that had been electrodeposition-coated up to that point and increase the number of automobiles produced and shift to medium-scale production. In this case, the partition walls are removed and at least two adjacent tanks are combined, the combined tank is filled with an electrodeposition coating material, and the vehicle body being transported is immersed in the combined tank, and the one before the combining is completed. The electrodeposition coating should be performed in order by dividing the time required for electrodeposition between the parts of the tank and other tank parts. And butterflies.

  The invention described in claim 6 is an electrodeposition coating method applied from small-scale production to medium-scale production of automobiles. In the case of small-scale production, the first tank and the first tank are connected via a removable partition wall. When electrodeposition coating is performed by immersing the vehicle body in one of the first and second tanks of the electrodeposition tank partitioned into two tanks, and the tank inner wall becomes dirty, The electrodeposition paint is transferred to the other tank, and the car body is immersed in the other transferred tank and the electrodeposition coating is continued while washing one tank that has been electrodeposition-painted until then. When the number of production increases and it becomes necessary to shift to medium-scale production, the partition is removed, the first tank and the second tank are combined, filled with the electrodeposition paint, and conveyed. With the vehicle body immersed in the electrodeposition tank, the time required for electrodeposition is divided between the first tank part and the second tank part in order. And performing electrodeposition coating.

According to the first aspect of the present invention, using any one of the divided tanks, the electrodeposition paint is circulated by the circulation device, and the energization is performed by the energization device. In the case of a production volume that allows a vehicle body to be immersed in one tank, the takt time is shortened because the production volume has increased, and the tank of the tank that has been merged with the necessary bulkhead removed, of one tank before the merger. The time obtained by adding the time for immersing the vehicle body in the part and the time for moving from the one tank part to the other tank part combined with the car body and then staying at the other tank part is charged. Since it is possible to selectively use the amount of production that needs to be secured for the time required for coating, electrodeposition coating can be performed with high quality enough to cope with the increase in production There is an effect that can.
In addition, when electrodeposition coating is performed using any tank partitioned with a partition wall, maintenance such as cleaning can be performed on other unused tanks. In addition, it is possible to perform high quality electrodeposition coating while minimizing the situation where the production line is stopped.
According to the second aspect of the present invention, either the first tank or the second tank is used, and the electrodeposition paint is circulated from the overflow tank into the first tank and the second tank through the pressure feeding device, the piping, and the nozzle. While connecting the diaphragm anode plate and the bare anode plate to the anode of the power supply, the current collector plate of the hanger that holds the vehicle body as the work is connected to the cathode plate connected to the cathode of the power supply, and the tact is performed In the case of the production volume that can immerse the vehicle body for a certain time according to the time, the takt time is shortened because the production volume has increased, and the first tank and the second tank are removed and the first tank is removed. After adding the time for immersing the vehicle body in this part and the time to move from the first tank part to the second tank part in the electrodeposition tank while immersing the car body, In the case of production volume that needs to be secured as time for electrodeposition coating It becomes possible to selectively use the 択的, there is an effect that it is also possible to perform electrodeposition coating at a sufficiently high response quality for increased production.
Further, according to the invention described in claim 2, when electrodeposition coating is performed using either the first tank or the second tank, maintenance such as cleaning of the unused tank can be performed. Therefore, it is possible to perform high-quality electrodeposition coating while minimizing the situation where the production line is stopped due to maintenance or the like.
According to the third aspect of the present invention, since the vehicle body as the workpiece can be continuously and accurately transferred, there is an effect that smooth transfer can be performed without affecting other processes in the production line. .
According to the invention described in claim 4, since the hanger can be fixed to the carrier by bringing the hanger into contact with the lower surface of the carrier, there is an effect that the hanger can be stably held.
According to the invention described in claim 5, according to the production amount of the automobile, in the case of the production amount that can immerse the vehicle body that is a work for a certain time using any of a plurality of tanks, the production amount is Since the tact time is shortened, the bulkhead is removed and at least a plurality of tanks are used as one electrodeposition tank, and the body as a work is immersed in one tank part and another tank part of this electrodeposition tank. Since it is possible to selectively use the amount of production that needs to be secured, it is possible to perform electrodeposition coating with high quality enough to cope with the increase in production There is.
According to the invention described in claim 6, depending on the production volume of the automobile which is the object of electrodeposition coating, the vehicle body which is a work for a certain time is immersed using either the first tank or the second tank. In the case of the production volume that can be used, the tact time is shortened because the production volume has increased, and the first tank of this electrodeposition tank is used as one electrodeposition tank with the partition walls of the first tank and the second tank removed. It is possible to selectively use the case where it is necessary to secure the time for immersing the vehicle body in the part of the tank and the part of the second tank. There is an effect that electrodeposition coating can be performed.

Embodiments of the present invention will be described below with reference to the drawings.
As shown in FIGS. 1 and 2, the electrodeposition tank 10 is disposed on the downstream side (downstream side, rear side) of the welding process of the automobile production line, and immerses the vehicle body W of the automobile. A coating film is deposited by electrodeposition. The electrodeposition tank 10 is partitioned by a partition wall 27 into a first tank 11 on the upstream side and a second tank 12 on the downstream side, and the partition wall 27 is configured to be detachable. That is, in the state where the partition wall 27 is attached, the electrodeposition tank 10 is divided into the first tank 11 and the second tank 12 on the downstream side, and in the state where the partition wall 27 is removed, the united single electrodeposition tank 10 functions.

The first tank 11 and the second tank 12 are provided with overflow tanks 13 and 14, respectively. Pipes 15 and 16 are connected to the overflow tanks 13 and 14, and branch pipes 17 and 18 are branched and joined to the ends of the pipes 15 and 16. The branch pipes 17 and 18 are connected to riser pipes 19 and 20 on the bottom walls of the first tank 11 and the second tank 12, and the riser pipes 19 and 20 are opened in the first tank 11 and the second tank 12. Ejecting nozzles 21 and 22 are attached. In the middle of the pipes 15 and 16, pumps 23 and 24 (pressure feeding device A) and filters 25 and 26 are interposed. These overflow tanks 13 and 14, pipes 15 and 16, pumps 23 and 24, filters 25 and 26, riser pipes 19 and 20, and ejection nozzles 21 and 22 constitute a circulation device J.
The partition wall 27 is provided with a pipe 28 that opens in the first tank 11 and the second tank 12, and valves 29 and 30 are attached to both ends of the pipe 28. Furthermore, the both ends of the piping 31 which connects these are opened and connected to the bottom wall of the 1st tank 1 and the 2nd tank 12, and the pump 32 and the filter 33 are interposed in the middle of the piping 31.

Diaphragm anode plates 34 and 35 are disposed oppositely on the inner surfaces of both side walls of the first tank 11 and the second tank 12, respectively, and on the riser tubes 19 and 20 disposed on the bottom wall, 37 is disposed. The diaphragm anode plates 34 and 35 and the bare anode plates 36 and 37 are connected to anodes of power sources 60 and 63 provided outside the first tank 11 and the second tank 12, respectively.
Cathode plates 38 and 39 are respectively provided above the central portions of both side walls of the first tank 11 and the second tank 12 so as to be movable up and down by rods 42 and 43 of cylinders 40 and 41 connected to the upper part. The cathode plates 38 and 39 are disposed so as to be rotatable by 180 degrees in directions opposite to the facing directions by motors 44 and 45 connected to the base end sides of the cylinders 40 and 41.

Above the first tank 11 and the second tank 12, a transport rail 46 is disposed from the upstream side toward the downstream side. A carrier 47 is provided on the transport rail 46 through a roller 49 that is rolled by a servo motor 48 so as to be able to run on its own. A pair of chain blocks 53 and 54 operated by motors 51 and 52 are mounted on the support plate 50 of the carrier 47, and the chains 55 and 56 fed out from the chain blocks 53 and 54 pass through the support plate 50 and move downward. The hanger 57 is connected to both ends in the longitudinal direction of the base 58. A current collecting plate 59 is provided on both sides of the hanger 57 in the center in the longitudinal direction. The current collector plate 59 can be connected to the cathode plates 38 and 39 of the rods 42 and 43 of the cylinders 40 and 41. The transport rail 46, the servo motor 48, the roller 49, and the carrier 47 constitute a transport device H.
Here, a cylinder 61 having a buffer member 62 at the tip of the rod is placed on the shelf portion 12a on the side wall on the downstream side in the vehicle transport direction of the second tank 12, and the interior of the electrodeposition tank 10 from which the partition wall 27 is removed is The swing of the hanger 57 that moves toward the two tanks 12 can be stopped.
The power sources 60 and 63, the cathode plates 38 and 39, the current collector plate 59, the diaphragm anode plates 34 and 35, and the bare anode plates 36 and 37 constitute an energizing device T.

Next, the operation will be described.
First, in the case of small-scale production with 30,000 to 40,000 vehicles per year, as shown in FIGS. 3 to 5, a partition wall 27 is attached to the electrodeposition tank 10, and the electrodeposition tank 10 is set to the first tank. 11 and the second tank 12, and electrodeposition coating is performed using the first tank 11. The first tank 11 is filled with the electrodeposition paint, and the electrodeposition paint overflowing from the first tank 11 to the overflow tank 13 is sucked into the pump 23 interposed in the pipe 15 and is filtered. And is circulated by being ejected from the ejection nozzle 21 into the first tank 11 through the branch pipe 17 and the riser pipe 19.

The vehicle body W, which is a workpiece, is supported by a carrier 47 that travels along a transport rail 46 by a servo motor 48 and is transported from an upstream welding process.
When the vehicle body W stops above the first tank 11, the motors 51 and 52 disposed on the support plate 50 of the carrier 47 are operated, and the chains 55 and 56 wound around the chain blocks 53 and 54 are moved downward. It is paid out. As a result, the hanger 57 attached to the front ends of the chains 55 and 56 and in contact with the lower surface of the support plate 50 starts to descend, and the vehicle body W placed on the hanger 57 is immersed in the electrodeposition paint. And stop in this state.

  At this time, the base 58 of the hanger 57 is exposed on the electrodeposition paint. Next, a pair of cathode plates 38 and 39 waiting in opposite directions above the center portions of both side walls in the longitudinal direction of the first tank 11 are rotated by the motors 44 and 45 so as to face each other inward. The cylinders 40 and 41 are moved downward. As a result, the pair of cathode plates 38 and 39 abut on a pair of current collector plates 59 disposed at the center in the longitudinal direction of the base 58 of the hanger 57. Then, the electric circuit formed by the power source 60, the cathode plates 38 and 39, the current collector plate 59, the hanger 57, the vehicle body W, the electrodeposition paint, the diaphragm anode plate 34 and the bare anode plate 36 is energized for a predetermined time (see FIG. 4).

  By the way, during this time, the motors 51 and 52 are alternately operated a plurality of times, the chains 55 and 56 are wound up and unwound, and the vehicle body W is swung back and forth in the electrodeposition paint, whereby the roof and bonnet of the vehicle body W are obtained. Then, the air in the air pocket formed on the back surface of the wheel house or the bag-like portion is discharged. Thereby, the film thickness of the electrodeposition coating film electrically deposited on the surface of the vehicle body W can be made uniform.

  After the energization is completed, the cathode plates 38 and 39 are raised by the cylinders 40 and 41, and the motors 44 and 45 are operated so that the cathode plates 38 and 39 are in opposite directions from the opposed positions to be in a standby state. Then, the hangers 57 are raised by operating the motors 51 and 52 again, the base 58 of the hangers 57 is brought into contact with the lower surface of the support plate 50 to fix the hangers 57 to the carrier 47, and the servo motor 48 is driven to drive the carrier. 47 is moved to the downstream side along the transport rail 46 (see FIG. 5).

By the way, when the production amount of the vehicle increases to 40,000 to 80,000 units per year, the tact time is shortened, so that the electrodeposition using only the first tank 11 of the electrodeposition tank 10 described above is used. Painting time cannot be secured. Therefore, as shown in FIGS. 6 to 11, the partition wall 27 that partitions the first tank 11 and the second tank 12 is removed from the electrodeposition tank 10, and the first tank 11 and the second tank 12 are communicated with each other. And combine with electrodeposition paint. Thereby, the inside of the electrodeposition tank 10 is filled with the electrodeposition paint, and the electrodeposition paint overflowing from the portion of the first tank 11 to the overflow tank 13 is sucked into the pump 23 interposed in the pipe 15, After being filtered by the filter 25, it is ejected from the ejection nozzle 21 into the first tank 11 via the branch pipe 17 and the riser pipe 19 and circulated. Here, the tact time is a time calculated by dividing the operating time excluding the break time and changeover time of the day by, for example, the number of units scheduled to be produced per day, and based on this, the body of another production line The conveyance conveyor speed and the traveling speed of the carrier 47 are adjusted.
In addition, the electrodeposition paint overflowing from the second tank 12 to the overflow tank 14 is sucked into the pump 24 interposed in the pipe 16, filtered by the filter 26, via the branch pipe 18 and the riser pipe 20, It is in a state where it is ejected from the ejection nozzle 22 into the second tank 12 and circulated.

The vehicle body W, which is a workpiece, is supported by a carrier 47 that travels along a transport rail 46 by a servo motor 48 and is transported from an upstream welding process.
When the vehicle body W stops above the portion of the first tank 11 of the electrodeposition tank 10 (see FIG. 6), the motors 51 and 52 disposed on the support plate 50 of the carrier 47 are operated, and the chain blocks 53 and 54 are moved. The wound chains 55 and 56 are drawn out downward. As a result, the hanger 57 attached to the front ends of the chains 55 and 56 and in contact with the lower surface of the support plate 50 starts to descend, and the vehicle body W placed on the hanger 57 is immersed in the electrodeposition paint. And stop in this state.

At this time, the base 58 of the hanger 57 is exposed on the electrodeposition paint. Next, a pair of cathode plates 38 and 39 waiting in opposite directions above the center portions of both side walls in the longitudinal direction of the first tank 11 are rotated by the motors 44 and 45 so as to face each other inward. The cylinders 40 and 41 are moved downward. As a result, the pair of cathode plates 38 and 39 abut on a pair of current collector plates 59 disposed at the center in the longitudinal direction of the base 58 of the hanger 57. The electric circuit formed by the power source 60, the cathode plates 38 and 39, the current collector plate 59, the hanger 57, the vehicle body W, the electrodeposition paint, the diaphragm anode plate 34, and the bare anode plate 36 has a predetermined time (necessary for electrodeposition). Energization is performed for half the time (tact time) (see FIG. 7).
At this time, similarly to the case described above, the motors 51 and 52 are alternately operated a plurality of times, the chains 55 and 56 are wound and unwound, and the vehicle body W is swung back and forth in the electrodeposition paint. Then, the air in the air pocket formed on the roof of the vehicle body W, the bonnet, the rear surface of the wheel house or the bag-shaped portion is discharged. Thereby, the film thickness of the electrodeposition coating film electrically deposited on the surface of the vehicle body W can be made uniform.

When energization for half the predetermined time is completed, the cathode plates 38 and 39 are raised by the cylinders 40 and 41, and the motors 44 and 45 are operated so that the cathode plates 38 and 39 are opposed to each other from the opposed positions. Set to the standby state. Then, by operating the servo motor 48, the carrier 47 is moved along the transport rail 46 to the second tank 12 and stopped (see FIG. 8).
At this time, in order to avoid the hanger 57 swinging due to the conveyance and the vehicle body W coming into contact with the electrodeposition tank 10, the second tank 12 is disposed on the shelf 12 a on the side wall on the downstream side in the vehicle conveyance direction. The cylinder 61 is extended to extend the buffer member 62 disposed at the tip of the rod of the cylinder 61 into the second tank 12, and the swing of the hanger 57 is stopped (see FIG. 11).

Next, the buffer member 62 is returned to the base position, and the pair of cathode plates 38 and 39 waiting in opposite directions above the center of both side walls in the longitudinal direction of the second tank 12 are moved by the motors 44 and 45. It rotates in the opposite direction and is further lowered downward by the cylinders 40 and 41.
As a result, the pair of cathode plates 38 and 39 abut on a pair of current collector plates 59 disposed at the center in the longitudinal direction of the base 58 of the hanger 57. The electric circuit formed by the power source 63, the cathode plates 38 and 39, the current collector plate 59, the hanger 57, the vehicle body W, the electrodeposition paint, the diaphragm anode plate 35 and the bare anode plate 37 is the remaining half of the predetermined time. Energization is performed (see FIG. 9). At this time, the next transported vehicle body W is immersed in the first tank 11 and energized for half the predetermined time.

Next, when the energization for the remaining half of the predetermined time is completed, the cathode plates 38 and 39 are raised by the cylinders 40 and 41, the motors 44 and 45 are operated, and the cathode plates 38 and 39 are put on standby in opposite directions.
. Then, the hangers 57 are raised by operating the motors 51 and 52 again, the base 58 of the hangers 57 is brought into contact with the lower surface of the support plate 50 to fix the hangers 57 to the carrier 47, and the servo motor 48 is driven to drive the carrier. 47 is moved to the downstream side along the transport rail 46 (see FIG. 10). At this time, the vehicle body W that has been energized for half the predetermined time at the site of the first tank 11 has moved to reach the site of the second tank 12.

Here, when small-scale production of 30,000 to 40,000 units or less is performed annually using the first tank 11, dust and iron powder deposited on the vehicle body W in the first tank 11 are accumulated. If the electrodeposition paint is agglomerated and settled, and if electrodeposition is continued as it is, there is a possibility that dust, iron powder, and the electrodeposition paint that has agglomerated and settled adhere to the vehicle body W. As shown, the valves 29 and 30 of the pipe 28 arranged in the partition wall 27 are opened to transfer the electrodeposition paint from the first tank 11 to the second tank 12, and then arranged in the middle of the pipe 31. Similarly, the electrodeposition paint can be completely transferred from the first tank 11 to the second tank 12 by operating the pump 32.
Therefore, when the transfer of the electrodeposition paint is completed, the electrodeposition paint is transferred using the second tank 12 as the transfer destination while continuing the electrodeposition coating in the same procedure as that performed in the first tank 11 until now. The first tank 11 that has become empty can be cleaned. That is, the carrier 47 is stopped above the second tank 12 as shown in FIG. 12, the vehicle body W is immersed in the second tank 12 as shown in FIG. 13, and is raised as shown in FIG. Therefore, if there is a day when the line is stopped, the cleaning work can be sufficiently performed.

  According to the above embodiment, when the production amount of the automobile is small-scale production of 30,000 to 40,000 or less per year, the electrodeposition paint is applied only to one of the first tank 11 and the second tank 12. Thus, electrodeposition coating can be performed in a tank filled with the electrodeposition paint. As a result, the transported vehicle body W is immersed in one of the first tank 11 and the second tank 12 for a time corresponding to the tact time and is subjected to electrodeposition coating.

Next, for example, if electrodeposition coating is performed in the first tank 11 and the first tank 11 continues to be used, dust and iron powder deposited and carried on the vehicle body W in the first tank 11 accumulate, When the electrodeposition paint is agglomerated and settled and the electrodeposition is continued as it is, dust, iron powder, and the agglomerated and settled electrodeposition paint adhere to the vehicle body W. As described above, the first tank 11 electrodeposition paint can be transferred to the 2nd tank 12, and while performing the electrodeposition coating in the 2nd tank 12, the 1st tank 11 can be cleaned.
Therefore, in the case of the above-mentioned small-scale production, even if maintenance such as cleaning is required for one of the first tank 11 and the second tank 12 and cannot be used, electrodeposition coating is performed using the other. Therefore, high-quality electrodeposition coating can be performed while minimizing the situation where the production line is stopped.

In addition, when the production volume increases to 40,000 to 80,000 medium-scale production annually, the partition wall 27 of the electrodeposition tank 10 is removed and the electrodeposition tank 10 is used as one tank, and the vehicle body which is a workpiece After moving W in the electrodeposition tank 10 to the part of the second tank 12 while the vehicle body W is immersed, the time in which the electrodeposition coating can be performed on the part of the first tank 11 according to the shortened tact time. The time required for electrodeposition coating at the site of the second tank 12 can be added to ensure the immersion time necessary for electrodeposition coating. Therefore, even if the tact time is shortened, the electrodeposition coating can be carried out while ensuring the time during which it is immersed in the electrodeposition bath 10 as a whole and being coated.
And by moving the vehicle body W in the electrodeposition paint from the first tank 11 to the second tank 12 in this way, the air pockets formed in the vehicle body effectively by the pressure of the electrodeposition paint are eliminated. As a result, unevenness of electrodeposition coating can be eliminated.

  Further, since the carrier 47 is moved on the transport rail 46 via the roller 49 by the servo motor 48 disposed on the carrier 47, the vehicle body W can be transported continuously and accurately. Therefore, smooth conveyance of the vehicle body W can be realized without affecting other processes in the production line.

  Below the carrier 47, a pair of chains 55, 56 that are moved up and down by two motors 51, 52 disposed on the carrier 47 are provided, and a hanger 57 is attached to the ends of the chains 55, 56. The hanger 57 can be fixed to the carrier 47 by bringing the hanger into contact with the lower surface of the carrier. Therefore, the hanger 57, that is, the vehicle body W that is a workpiece can be stably held.

The present invention is not limited to the above embodiment. For example, in the case of medium-scale production, half of the predetermined time is a part of the first tank 11 and half of the remaining predetermined time is a part of the second tank 12. Although the aspect which supplies with electricity was demonstrated, about the allocation of the electricity supply time in the site | part of the 1st tank 11 and the 2nd tank 12, it can set freely. In addition, when the first tank 11 and the second tank 12 are combined and used, the voltage and current values of the power supply 60 of the first tank 11 and the power supply 63 of the second tank 12 do not have to be the same. For example, the voltage of the power source 63 can be set higher than that of the power source 60 in order to increase the film thickness of the electrodeposition coating film deposited on the surface of the vehicle body by energization for a predetermined time and improve the quality.
Furthermore, even if the energization time is shortened by increasing the voltage of the power supply 63, it is possible to obtain a film thickness equivalent to that when energization is performed for a predetermined time.
Further, in the case of medium-scale production, the vehicle body W is not swung back and forth in the portion of the second tank 12, but by carrying out this, the film thickness of the electrodeposition coating film can be made more uniform.
Furthermore, although the case where the electrodeposition tank 10 was divided | segmented into the 1st tank 11 and the 2nd tank 12 was demonstrated, it is applicable also when the electrodeposition tank 10 is divided | segmented into two or more tanks. In this way, if the partition is removed in order as the production volume increases, the number of tanks that can be used to ensure the optimal electrodeposition coating time according to the tact time that changes according to the change in production volume is selected. There is a merit that can be done.

1 is a side view of an embodiment of the present invention. It is a front view of an embodiment of this invention. It is a side view which shows the coating state in the case of small-scale production. It is a side view which shows the coating state in the case of small-scale production. It is a side view which shows the coating state in the case of small-scale production. It is a side view which shows the coating state in the case of medium scale production. It is a side view which shows the coating state in the case of medium scale production. It is a side view which shows the coating state in the case of medium scale production. It is a side view which shows the coating state in the case of medium scale production. It is a side view which shows the coating state in the case of medium scale production. It is a partial top view of a 2nd tank. It is a side view which shows the coating state at the time of using a 2nd tank. It is a side view which shows the coating state at the time of using a 2nd tank. It is a side view which shows the coating state at the time of using a 2nd tank.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electrodeposition tank 11 1st tank 12 2nd tank 13, 14 Overflow tank 15, 16 Piping 21, 22 Injection nozzle 27 Partition 34, 35 Partition anode plate (anode)
36, 37 Bare anode plate (anode)
38,39 Cathode plate (cathode)
46 Transport rail 47 Carrier 48 Servo motor 49 Roller 51, 52 Motor (drive source)
55, 56 Chain (suspending member)
57 Hanger 59 Current collector plate 60, 63 Power source A Pressure feeding device H Conveying device J Circulating device T Current feeding device W Car body

Claims (6)

  The electrodeposition tank can be divided into a plurality of tanks via removable partition walls and can be at least partially combined, and a circulation device for circulating the electrodeposition paint is provided in each tank, Provide an energization device provided with an anode provided on the inside, a cathode provided on the outside and a power source, and configured to be able to immerse the vehicle body conveyed via the conveying device in any of the tanks, and connected to the cathode, An electrodeposition coating apparatus configured to be able to be shut off and configured to be movable in a state where the vehicle body transported via the transport apparatus is immersed across a combined tank.   The electrodeposition tank is partitioned into a first tank and a second tank through a removable partition, and an overflow tank is provided in the first tank and the second tank. An electrodeposition paint circulation pipe connected to the second tank via a pressure feeding device is connected, and an end of the pipe is provided with a nozzle that opens in the first tank and the second tank, A diaphragm anode plate is disposed on the inner wall of the first tank and the second tank, and a bare anode plate is disposed on the bottom wall, and the diaphragm anode plate and the bare anode plate are connected to a power source anode, A cathode plate that is rotatable about a vertical axis and can be raised and lowered is disposed above both side walls of the first tank and the second tank, and each cathode plate is connected to the cathode of the power source and moved along the transport rail. A hanger that supports the vehicle body is provided on a carrier that can be configured, and this hanger is provided so that it can be raised and lowered. A plate provided, this connecting a current collecting plate to the cathode plate by the elevating operation of the hanger, electrodeposition coating device, characterized in that the disconnectable configured.   The electrodeposition coating apparatus according to claim 2, wherein the carrier moves on the transport rail via a roller by a servo motor disposed on the carrier.   Below the carrier, a pair of suspension members that are lifted and lowered by a plurality of driving sources disposed on the carrier are provided, the hanger is attached to the tip of the suspension member, and the hanger is applied to the lower surface of the carrier. 4. The electrodeposition coating apparatus according to claim 2, wherein the electrodeposition coating apparatus is disposed so as to be able to contact and separate.   It is an electrodeposition coating method that is applied from small-scale production to medium-scale production of automobiles. In the case of small-scale production, any one of the tanks divided into a plurality of tanks through removable partition walls. Electrodeposition coating is performed by immersing the vehicle body, and when the inner wall of the tank becomes dirty, the electrodeposition paint is transferred from the one tank to another tank, and the vehicle body is immersed in the other transferred tank. If it is necessary to wash one tank that has been used for electrodeposition coating while the electrodeposition coating continues and the number of automobile production increases and shift to medium-scale production, the partition is removed. Combine at least two adjacent tanks, fill the combined tank with the electrodeposition paint, and immerse the transported vehicle body in the combined tank and place the tank in one tank and the other tank An electrodeposition coating method characterized in that the electrodeposition coating is carried out in order by dividing the time required for electrodeposition at the site.   This is an electrodeposition coating method applied to small-scale production to medium-scale production of automobiles. In the case of small-scale production, the electrolysis coating is formed in a first tank and a second tank through a removable partition wall. When the body is immersed in one of the first tank and the second tank and electrodeposition coating is performed, and the inner wall of the tank becomes dirty, the electrodeposition paint is applied from the one tank to the other tank. While transporting and immersing the vehicle body in the other transferred tank and continuing the electrodeposition coating, one tank that had been electrodeposition-coated so far was washed, and the number of cars produced increased to a medium scale When it is necessary to shift to production, the partition wall is removed, the first tank and the second tank are combined and filled with the electrodeposition paint, and the transported vehicle body is immersed in the electrodeposition tank The electrodeposition coating is performed in order by dividing the time required for electrodeposition in the first tank part and the second tank part in the state. Electrodeposition coating method to.

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