JP4866980B2 - Electrodeposition coating equipment - Google Patents

Description

The present invention relates to an electrodeposition coating apparatus and an electrodeposition coating method, and in particular, when a large variety and a small amount of objects to be coated are continuously conveyed, the coating thickness required for each object to be coated is increased. The present invention relates to an electrodeposition coating apparatus capable of electrodeposition coating.

Electrodeposition coating is easy to automate the coating process, has good throwing power on the coating object, and can form a uniform film thickness, so it can be used as a base coating method for automobile bodies and parts. Has been.

2. Description of the Related Art In recent years, with the production of various types of products in small quantities and custom production, there has been a demand for production in small lots of bodies and parts corresponding to vehicle types. For this reason, in the field of undercoating of these parts, it is required to respond to small lots, and it can be handled with one painting line without changing the parts of the electrodeposition coating equipment for each type of object to be coated. Further, there is a need for an electrodeposition coating apparatus that can automatically cope with various types of objects to be coated being continuously conveyed and can achieve the required coating film thickness and coating film quality.

In order to satisfy the above-mentioned problems, it is necessary to control the total amount of current flowing in the object to be coated for each type of object to be coated. The voltage or voltage on the anode side (electrode) or cathode side (current collector rail) is required. It is necessary to control the energization time.
As an example of the representative invention, an electrodeposition coating method with the following improvements is disclosed.
(1) Use a combination of an electrode that can be energized constantly and an electrode that can be energized, depending on the type of the object to be coated. Then, an electrodeposition coating method that realizes an appropriate coating thickness according to the object to be coated by making the coating with a thin film thickness (Patent Document 1).
(2) The current collecting rail is divided to form a divided rail portion, and the divided rail portion is energized and controlled separately from the other rail portions to form an electrodeposition coating film having a certain thickness on the object to be coated. A coating method (Patent Document 2).
JP-A-60-96795 Japanese Patent Laid-Open No. 1-246397

However, the above prior art has the following problems. That is,
(1) In the electrodeposition coating method (Patent Document 1) using a combination of an electrode that is normally energized and an electrode that can be energized, that is, in the energization control on the electrode side, the electrode is cut off when the energization is interrupted. As a result, paint adheres to the surface of the electrode, which hinders the efficiency of subsequent electrodeposition coating. In addition, since the current to be coated is not completely cut off, the electrodeposition coating takes place between the other current-carrying electrodes and it is difficult to obtain the required film thickness.
(2) An electrodeposition coating method (Patent Document 2) in which a current collecting rail is divided and an electric coating film having a certain thickness is formed on an object to be coated by separately energizing and controlling the divided rail portions. In energization control on the electric rail side, the film thickness of the electrodeposition coating can always be controlled only to a constant thickness, and various film thickness control cannot be performed according to the type of the object to be coated.

Accordingly, an object of the present invention is to perform electrodeposition coating with a desired coating thickness required for each object when a large variety and a small amount of objects are conveyed continuously in the electrodeposition process. Another object of the present invention is to provide an electrodeposition coating apparatus capable of performing electrodeposition coating and film thickness control with an inexpensive apparatus.

As a result of studying the problems of the prior art, the present inventors have divided a plurality of rails in the conveying direction of the object to be coated, and the divided partial rails can be energized independently, The idea is to provide an electrodeposition coating apparatus with a coating material identification device, a position sensor, and a control device that issues a signal for energizing an object to be coated.
Thus, by adopting such a configuration, the electrodeposition coating apparatus of the present invention sets the energizing time for each partial rail of the current collecting rail according to the type of the object to be coated, and the set energizing time. Accordingly, it is possible to control the start and stop of energization for each partial rail, thereby enabling the setting of the energization time and the control of the energization time according to each object to be coated, that is, the coating thickness can be controlled. They found and completed the present invention.

That is, the present invention
In slipper dip type electrodeposition coating equipment,
An electrodeposition tank for storing the electrodeposition paint;
Electrodes installed in the electrodeposition bath;
Conveying device equipped above the electrodeposition tank, comprising a hanger for suspending the object to be coated and a conveyor for transferring the hanger;
A first-stage rail provided in parallel with the conveyor in the entrance area of the electrodeposition tank, and a second-stage rail provided in parallel with the conveyor in the entire sinking area and exit tank area of the electrodeposition tank A current collecting rail for energizing the object to be coated through the hanger;
An energizing device for applying a voltage between the electrode and the current collector rail;
An identification device for identifying the type of object to be conveyed;
A position sensor disposed at a plurality of positions along the transfer path of the hanger, for detecting the arrival of the object to be conveyed;
An electrodeposition coating apparatus comprising a control device that issues a command to start and stop energization of an object to be energized to the energization device,
The second stage rail of the current collecting rail is divided into a plurality of partial rails, and in this case, the divided portion is arranged on the hanger so that one article to be coated is conveyed to one partial rail. It is installed according to the transfer pitch,
In addition, the energization device, for the second-stage rail, is configured in a circuit so that voltage can be applied independently for each divided partial rail,
In addition, the position sensor is that the object to be coated has arrived at the entry tank position or the voltage application start position, that the object has arrived at the transfer position from the first rail to the second rail of the current collecting rail, Further, each of the objects to be coated is arranged for each type of the object so as to detect that the object has arrived at the transfer position from one partial rail to the next partial rail of the second-stage rail, and the arrangement Each sensor is configured to send the detection signal to the control device when the arrival of the object to be coated is detected.
The identification device is configured to identify the type of the object to be conveyed and to send the identification signal to the control device before the object enters the electrodeposition tank. Furthermore, when the control device receives the identification signal from the identification device, the thickness of the coating film required for each type of the object to be coated, the transfer speed of the hanger, and the entrance area of the electrodeposition tank Based on pre-input information such as the applied voltage boosting program and the constant voltage applied voltage value in the entire submerged area and the outgoing tank area, the energization time and the application time when the object is applied with voltage from the first rail. The energization time when the voltage is applied from each partial rail of the second stage rail is determined according to the type of the object to be conveyed, and based on each determined energization time From the plurality of position sensors When each detection signal is received, energization is started to apply voltage independently to the plurality of objects to be conveyed via the first-stage rail or the individual partial rails of the second-stage rail. Alternatively, the present invention relates to an electrodeposition coating apparatus configured to send an energization stop command signal to the energization apparatus.

Moreover, in a preferred aspect of the present invention, in the above electrodeposition coating apparatus,
The plurality of position sensors are:
It arrives at the position immediately before the workpiece is transferred from the first rail to the second rail of the current collector rail, and then arrives at the position after the transfer, and the workpiece is out of the second rail. It is arranged for each type of object to be detected so that it arrives at the position just before changing from one partial rail to the next partial rail and then arrives at the position after changing. When the arrival of the object to be coated is detected in each sensor, the detection signal is configured to be sent to the control device,
In addition, the control device
When a detection signal is received from the position sensor that the workpiece has arrived at a position immediately before the current collector rail is transferred from the first rail to the second rail, the second workpiece is transferred to the second workpiece. An energization start command signal is sent to the energization device to apply a voltage via the first partial rail of the step rail, and then the object to be coated is fed from the first step rail to the second step rail from the position sensor. When receiving a detection signal that it has arrived at the position after having transferred to, a command signal to stop energization is sent to the energization device to finish voltage application via the first rail, and
When a detection signal is received from the position sensor that the article has arrived at a position immediately before the second partial rail is transferred from the first partial rail to the second partial rail, the conveyed article to be conveyed The energization start command signal is sent to the energization device to be applied through the second partial rail during the energization time determined for the next partial rail, and the workpiece is removed from the second partial rail. When the determined energization time ends before the transfer to the third partial rail, a command signal to stop energization is sent to the energization device at the end, and at the same time, the object to be coated is second-stage from the position sensor. When receiving a detection signal that the position has arrived after changing from the first partial rail to the second partial rail, an energization stop command signal is sent to finish voltage application via the first partial rail. Sent to the serial power equipment, and,
When the workpiece is transferred from the second partial rail to the third partial rail, and then transferred to the subsequent partial rail, it is energized as in the case of the transfer from the first partial rail to the second partial rail described above. The present invention relates to an electrodeposition coating apparatus characterized by controlling start and stop thereof.

According to the present invention, when a wide variety and a small amount of objects to be coated are transported continuously in the electrodeposition coating process, each can be electrodeposition coated with a desired coating thickness required for each object to be coated, And the electrodeposition coating apparatus which can perform electrodeposition coating and film thickness control with an inexpensive apparatus can be provided.

That is, in the electrodeposition coating apparatus of the present invention, the type of the object to be continuously conveyed is first detected before entering the electrodeposition tank, and the type of the object to be input that has been input in advance. Information such as the coating thickness required for each type, the transfer speed of the hanger, the applied voltage boosting program in the entrance area of the electrodeposition tank, and the applied voltage value of constant pressure in the entire immersion area and exit area Accordingly, the energization time for each object is determined. And, as the object to be coated is conveyed into the electrodeposition tank, based on the detection signal from the position sensor and each energization time determined in advance, each object to be coated is connected via the current collecting rail. A voltage is applied independently for each object to be coated.
At this time, the current collecting rail is set in parallel with the conveying direction of the conveyor, and the first-stage rail installed in the entrance tank area of the electrodeposition tank, and the second rail installed in the entire sink area and the exit tank area of the electrodeposition tank. The second stage rail is divided into a plurality of partial rails, and each partial rail of the first stage rail and the second stage rail can be independently applied with a voltage. It is configured.
Moreover, the division | segmentation part of a 2nd step rail is set according to the space | interval which a to-be-coated object is conveyed, ie, a transfer pitch, so that one to-be-coated object may be conveyed with respect to one partial rail.
Furthermore, the position sensor indicates that the object to be coated has arrived at the entrance position of the electrodeposition tank or the voltage application start position, and the position of the object to be transferred from the first rail to the second rail of the current collecting rail. Arranged for each type of coating so that it can be detected that the coating has arrived, and that the coating has arrived at the transfer position from one partial rail to the next partial rail. Has been. And when each sensor detects the arrival of an object to be coated, the detection signal is sent to the control device.
Here, for example, the object A to be conveyed (total energization time a) is smaller in size than the object B to be subsequently conveyed (total energization time b), that is, it is required for electrodeposition coating. Consider a case where the total energization time is short (a <b). Specifically, the energizing time that is set when the article A comes in the middle of the third partial rail along the transfer direction of the second-stage rail ends, and the article B becomes the second-stage rail. Let us consider a case where the energization time set when the fourth partial rail is reached is terminated.
Now, when the article A is transferred to the third partial rail of the second-stage rail, the article B is a partial rail of the second-stage rail different from the article A, for example, the second rail by the above configuration. You are on a partial rail.
Since the partial rails can be energized independently, when the article A comes in the middle of the third partial rail, that is, when the energization time of the article A has elapsed, Only the voltage application to the third partial rail of the second stage rail on which the object A is on is completely stopped, and the voltage application to the second partial rail on which the object B is on is maintained as it is. Is possible.
When the article A is transferred to the fourth partial rail and subsequently the article B is newly transferred to the third partial rail through which the article A has passed, the energizing time for the article B is determined. Has not been completed, energization to the third partial rail is started again, and energization is maintained in the third partial rail and halfway through the fourth partial rail until the coating B finishes the energization time. can do.
Thus, in the electrodeposition coating apparatus of the present invention, it is possible to control the coating thickness according to the type of the object to be coated, that is, to control the energization time with high accuracy.

In the electrodeposition coating apparatus of the present invention, the second stage rail is divided into a plurality of partial rails, and the energization time is controlled by starting, maintaining, and shutting off the energization of each partial rail independently. No need for multiple power supplies for the number of partial rails.
Furthermore, since the energization time can be controlled only by the current collecting rail, adhesion of the electrodeposition paint to the electrode surface can be prevented, and a complicated control device is not required, so that the operation cost and the device cost are also reduced. Can do.

Embodiments of the present invention will be specifically described below.
The electrodeposition coating apparatus of the present invention is an electrodeposition coating apparatus capable of controlling the energization time according to the type of each object to be coated when various objects are continuously conveyed. , A transport device composed of a hanger and a conveyor, a current collecting rail composed of a first-stage rail and a second-stage rail composed of divided partial rails, an energizing device, an identification device, a position sensor, and an energizing control device.

Any electrodeposition tank may be used as long as it stores electrodeposition paint and can completely saturate the object to be coated. It can be a metal tank.

A plurality of electrodes may be installed in the electrodeposition tank in the depth direction or length direction of the electrode tank, and depending on the position in the electrodeposition tank, a larger number of electrodes may be used than in other positions. An electrode may be installed.

The hanger may be any metal object that can suspend the object to be coated, such as hanging the object to be coated from above or supporting it from below. The object to be coated is transported by a structure comprising a hanger for hanging the hanger and a conveyor connected to the hanger. Preferably, a mechanism for swinging the object to be coated in the electrodeposition tank is provided. At this time, it is preferable that the hanger is freely detachable from the conveyor, and according to the number of objects to be coated, for example, when the number of objects to be coated is small, the number of hangers to be connected to the conveyor is determined. Preferably, it can be reduced.
And a conveying apparatus shall be installed above an electrodeposition tank, and it is desirable to install in the direction of the longitudinal direction of an electrodeposition tank preferably.

It is desirable that the current collecting rail be installed in parallel with the transfer direction of the hanger, and the object to be coated can be maintained in an energized state via the current collecting rail and the hanger. The current collector rail is installed in the entrance area of the electrodeposition tank, and the first-stage rail can step up the voltage to a predetermined voltage when the object to be coated is transported and submerged in the electrodeposition tank And a second-stage rail that is installed in all the submerged areas and outlet areas of the electrodeposition tank and can energize a constant voltage boosted by the first-stage rail. The second-stage rail is further divided into a plurality of partial rails, and the energization device is configured so that each of the partial rails can independently apply a voltage.
Also, at this time, the divided part of the second rail is that the length of the divided partial rail is shorter than the transfer pitch of the hanger in consideration of the electrodeposition coating time and the conveying speed of the conveying device, that is, one partial rail. It is desirable to set so that one article to be coated is conveyed.

As the energization device, a rectifier or the like that converts an AC power source, which is a main power source, into a direct current is used. The circuit is configured so as to be installed at least at two places, that is, a first stage rail) and a stage where a constant voltage is subsequently applied (second stage rail).

The identification device for the object to be coated is preferably installed before the object enters the electrodeposition tank, and identifies the object to be coated depending on the light-shielding situation in the phototube, or is attached to a hanger or the like. Those having a function of identifying the object to be coated by a coating information storage device or the like are desirable.
The identification device is configured to send the identification signal to the control device after identifying the type of the object to be coated.

As the position sensor of the object to be coated, it is preferable to use, for example, a limit switch generally used as a detection device. The position sensor indicates that the object to be coated has arrived at an entry position of the electrodeposition tank (a position where the object to be immersed in the electrodeposition tank) or a voltage application start position, and the object to be coated is one level of the current collecting rail. It is confirmed that the transfer position from the second rail to the second partial rail has been reached, and that the article to be coated has arrived at the transfer position from one partial rail to the next partial rail. It is arranged for each type of object to be detected. Further, the position sensor has arrived at a position immediately before the object to be coated is transferred from the first rail to the second rail of the current collecting rail, and subsequently has arrived at a position after the transfer, and the object to be coated is Each type of article to be coated is detected so that it arrives at a position immediately before the transfer from one partial rail to the next partial rail of the second stage rail, and then arrives at the position after the transfer. Respectively.
And when this position sensor detects arrival of a to-be-coated object in each sensor arrange | positioned as mentioned above, it is comprised so that the detection signal may be sent to a control apparatus.

Upon receipt of the identification signal from the identification device, the energization time control device receives the coating thickness required for each type of workpiece inputted in advance, the transfer speed of the hanger, and the input of the electrodeposition tank. Based on information such as the applied voltage boosting program in the tank area and the applied voltage value of the constant pressure in all submerged areas and starting areas, the energization time when the voltage is applied from the first-stage rail, and the coated The energization time when a voltage is applied from each partial rail of the second stage rail,
It is determined according to the type of the object to be conveyed. At the same time, when the detection signal from the position sensor is received based on each determined energization time, each of the partial rails of the first-stage rail or the second-stage rail is independently used. In order to apply a voltage, the circuit is configured to send an energization start or energization stop command signal to the energization device.
Further, the control device may be configured to send an energization command signal for maintaining / stopping energization to each partial rail of the first-stage rail or the second-stage rail to an energization controller that performs energization on / off control. In this case, it is desirable that the energization controller be installed between the energization device and each partial rail of the first-stage rail or the second-stage rail.

Preferred embodiments of the present invention will be described more specifically with reference to the drawings.
FIG. 1 is a diagram showing an electrodeposition coating apparatus according to an embodiment of the present invention. While an object to be coated 4 is conveyed at a constant speed using a hanger 3 and a conveyor 2, an electrodeposition coating 1a in an electrodeposition tank 1 is applied. This is an electrodeposition coating apparatus that performs electrodeposition coating by applying voltage between the article to be coated 4 and the electrodes 5 (5a to 5d) through the current collecting rails 6 (6a to 6f).

Here, the structure of the electrodeposition coating apparatus of an Example and each part comprised are demonstrated.
The electrodeposition tank 1 employs a boat-shaped metal tank whose inner surface is lined with an electrical insulating agent such as polyvinyl chloride, and stores the electrodeposition paint 1a therein.

The hanger 3 is connected to the conveyor 2 via the insulating part 13, and the current collector 12 provided on the top of the hanger 3 is configured to come into contact with the current collector rail 6 (6 a to 6 f).

For example, there are relatively large objects (4a) such as a vehicle body (body) and relatively small objects (4b and 4c) such as parts, and these (4a, 4b and 4c) are mixed. The hanger 3 is continuously suspended and conveyed to the electrodeposition tank 1.

The current collecting rail 6 is installed in parallel with the conveyor 2, and the current collecting rail 6 is composed of rails (6a, 6f) of 0V at all times and rails (6b to 6e) to which voltage is applied. Furthermore, the rail to which voltage is applied is composed of a first-stage rail (6b) and a second-stage rail (6c to 6e) consisting of a plurality of partial rails, each of which can be applied with voltage independently. The circuit is configured as shown.
And the length is set so that one to-be-coated object may be conveyed with respect to each rail of each of the rails 6b to 6e to which voltage is applied.
In consideration of the size of the object to be coated 4, in the present embodiment, the first partial rail 6c of the second-stage rail is a rail that always applies a constant voltage regardless of the type of object to be coated. The second partial rail 6d and the third partial rail 6e of the rail are configured so as to freely control application / stop of voltage application.

The electrodes 5 (5a to 5d) are installed at positions where the electrodes 4 are immersed in the electrodeposition paint 1a in the electrodeposition tank 1 in parallel with the conveying direction of the article 4 and the conveyor 2 and the current collecting rail 6.

A DC power source 7 (7A, 7B) is adopted as the power source. At this time, two types of power sources are used: a DC power source 7A that applies voltage to the first-stage rail (6b) and a DC power source 7B that applies voltage to the second-stage rails (6c to 6e).
Further, the DC power supply 7A is configured so that the voltage rise and fall is controlled based on a boosting program input in advance to the control device 11 described later.

An on / off controller 8 (8A to 8C) is installed between the DC power supply 7A or 7B and the first-stage rail (6b) or the second-stage rail (6c to 6e). The on / off controller 8 turns on / off the circuit according to an energization command transmitted from the control device 11 described later, and thereby turns on / off the voltage application to the current collecting rail 6. Further, the on / off controller 8 is configured to transmit the current on / off status to the control device 11 as an on / off signal t in response to a command from the control device 11.
The installation purposes of the on / off controllers 8A to 8C are as follows.

A phototube sensor 10 is employed as an identification device for identifying the object 4 to be coated. The photoelectric tube sensor 10 is installed at a position before the coating object 4 enters the electrodeposition tank 1, identifies the type of the coating object 4 by passing through the coating object 4, and the identification signal r Is transmitted to the control device 11 described later.

Limit switches 9 (9-1 to 9-15) are employed as position sensors that detect the arrival of the article 4 to be coated. The limit switch 9 is installed in a plurality of locations for each type of the object to be coated in the conveying direction of the object 4, that is, along the transfer path of the hanger 3. The limit switch 9 is actuated by the passage of the object 4 to be detected, detects the arrival of the object 4 and further transmits a detection signal s to the control device 11 described later.
The installation positions of the limit switches 9 (9-1 to 9-15) are as follows. The branch numbers in FIG. 1 (for example, 9-1a and 9-1b) indicate that the installation location of the limit switch differs depending on the type of the object to be coated. In addition, the following shows the installation place as a case where the voltage is applied across the entire area of the second-stage partial rails 6c to 6e.

The control device 11 includes an information input unit, a transmission signal receiving unit from the photoelectric tube sensor 10 and the limit switch 9, a DC power source 7A, and command signal sending units to the on / off controllers 8A to 8C. And the thickness of the coating film required for each type of the object to be coated 4 in the information input unit of the control device 11, the transfer speed of the hanger 3, and the direct current power supply 7 </ b> A to the first rail 6 b of the current collecting rail 6 Voltage application program, and a constant voltage application voltage value from the DC power supply 7B to the second-stage rails 6c to 6e. Then, when the identification signal r of the object to be coated 4 is transmitted from the phototube sensor 10, the control device 11 energizes when the object to be coated 4 is applied with a voltage from the first rail 6b based on the input information. The energization time when a voltage is applied from each of the rails of the second-stage rails 6c to 6e is determined based on the type of the article 4 to be coated. Further, when the control device 11 receives the detection signal s of the limit switch 9 that detects the arrival of the article to be coated 4 based on the energization time determined as described above, the type of the detection signal s (the article to be coated) 4), a command signal p ₁ for executing a boosting program of the applied voltage is issued to the DC power source 7A,
Alternatively, the circuit is configured to issue an on / off command signal q ₁ to the on / off controllers 8A to 8C.

The current collectors 12 (12-1 to 12-14) on the current collecting rails 6 (6a to 6f) shown in FIG. 1 indicate positions corresponding to the installation positions of the limit switches 9. .

When electrodeposition coating is performed on the article 4 using the electrodeposition coating apparatus configured as described above, electrodeposition coating is achieved by a series of operations of each part as described below. However, as described above, in the present embodiment, in the first partial rail 6c of the second-stage rail, a voltage is applied to all regions of the partial rail 6c regardless of the type of article 4 to be coated. The voltage application is controlled in accordance with the size of the article 4 to be coated on the partial rail 6d or 6e of the second-stage rail.

1) First, before the coating object 4 enters the electrodeposition tank 1, the photoelectric tube sensor 10 identifies the type of the coating object 4 and transmits the identification signal r to the control device 11.
2) The control device 11 determines the energization time of the first-stage rail 6b and the second-stage rail partial rails 6c to 6e based on the previously input information and the object identification signal r transmitted from the phototube sensor 10. decide.
3) Upon receiving the detection signal s transmitted from the limit switch 9, the control device 11 instructs the DC power supply 7A and the on / off controllers 8A to 8C based on the energization time for each of the rails 6c to 6e. ₁ or command signal q ₁ is sent.
At this time, if the detection signal s is from the limit switch 9-2 (the position where voltage application (boosting) starts to be applied to the object 4), the control device 11 executes a boosting program for the applied voltage to the DC power source 7A. It sends a command signal p _1.
Further, detection signals s from limit switches 9-4 (position immediately before transfer from the first-stage rail 6b to the second-stage partial rail 6c) and 9-6 (position after transfer to the second-stage partial rail 6c). If so, an on / off command signal q ₁ is sent to the on / off controller 8A.
Furthermore, from 9-7 (position immediately before transfer from the partial rail 6c to the partial rail 6d of the second-stage rail) or 9-10 (position immediately before transfer from the partial rail 6d to the partial rail 6e of the second-stage rail) If it is the detection signal s, the controller 11 turns on / off the command signal to the on / off controller 8B or 8C in accordance with the energization time of the partial rail 6d or 6e of the second-stage rail determined previously. Send a q _1.
4) In the article 4 to be coated, when the energization time set when the article 4 is on the partial rail 6d or 6e of the second-stage rail is finished, the control device 11 is an on / off controller. The off command signal q ₁ is sent to 8B or 8C, and the application of the voltage to the partial rail 6d or 6e is stopped.

In order to increase the accuracy of electrodeposition coating in the above-described series of electrodeposition coating processes, the control device 11 controls the power supply 7A to confirm that the boosting of the first rail is completed in the limit switch 9-3. Then, a boost confirmation command signal p ₂ is sent, and in response thereto, the power source A transmits a boost condition signal u to the control device 11.
Similarly, the limit switch 9-6, 9-9 or 9-12 indicates that the article 4 has been transferred from the first rail to the second rail, or from the partial rail where the second rail is located. It is detected that the vehicle has moved to the next partial rail, and the detection signal s is transmitted to the control device 11. Further, in the limit switch 9-5, 9-8 or 9-11, the on / off state of the on / off controller 8A, 8B or 8C coincides with the command signal q1 from the controller 11 _first. In order to confirm that the controller 11 is on, the controller 11 sends an on / off controller command signal q ₂ to the on / off controller 8A, 8B or 8C, and the on / off controller 8A, 8B or 8C accordingly.
Transmits an on / off status signal t to the control device 11.

Here, when the article 4 is, for example, a car body 4a and parts 4b and 4c and the size is 4a>4b> 4c, the conveyance in the case of using the electrodeposition coating apparatus of this embodiment The relationship between the position and the DC applied voltage is shown in FIG.
At this time, the energizing time of the objects to be coated 4a to 4c is determined by the control device 11, and when this is replaced with each partial rail region to which a voltage is applied in the second rail of the current collecting rail, it becomes as follows.

Since the lengths of the partial rails 6c to 6e of the second-stage rail are adjusted as described above, for example, when the article 4b is transferred following the article 4a, the article 4a is moved to the partial rail 6e. In this case, the article 4b is on the partial rail 6d.

In the above case, for example, it is assumed that the object to be coated 4a is conveyed immediately after the object to be coated 4c, the object to be coated 4c is on the partial rail 6d, and the object to be coated 4a is on the partial rail 6c. Article to be coated. 4c central part rail 6d energizing time to reach the (near the center of the X ₃ section in FIG. 2) is completed, energization of the object to be coated 4c is cut off by the controller 11. At this time, since the partial rails 6d and 6c can be energized independently by adopting the above-described configuration, the energization of the partial rail 6c on which the article 4a is placed remains maintained.
Then, when the article 4c is transferred to the partial rail 6e and the article 4a is transferred to the partial rail 6d, the energization time of the article 4a has not ended, and thus the control device 11 starts energizing the partial rail 6d. However, since the energization time of the article to be coated 4c has already ended, the partial rail 6e is not energized.

As described above, by adopting the configuration shown in the present embodiment, the electrodeposition coating apparatus of the present invention detects the type of the object to be coated, and determines the energization time to the object to be coated according to the type. Depending on the determined energization time, different types of objects can be coated by performing electrodeposition coating on the object via the first rail of the current collecting rail and the second rail consisting of the divided partial rails. Even when the film is continuously conveyed, the target film thickness can be controlled with high accuracy.

FIG. 1 is a view showing an electrodeposition coating apparatus according to an embodiment of the present invention. FIG. 2 is a diagram showing the relationship between the transfer position and the DC applied voltage in the electrodeposition coating apparatus of FIG.

Explanation of symbols

1: Electrodeposition tank 1a: Electrodeposition paint 2: Conveyor 3: Hanger 4 (4a-4c): Coating object 4a: Coating object (body)
4b, 4c: Objects to be coated (parts)
5 (5a to 5d): Electrode 6 (6a to 6f): Current collecting rail 7 (7A, 7B): DC power supply 8 (8A to 8C): On / off controller 9 (9-1 to 9-15): limit switch 10: a photoelectric tube sensor 11: control unit 12 (12-1～12-15): current collector 13: insulating section p: control command signal to the DC power source 7A from 11 p _1: DC power supply 7A from the control device 11 Voltage application command signal p ₂ : Boost signal confirmation command signal from the control device 11 to the DC power supply 7A q: Command signal from the control device 11 to the on / off controllers 8A to 8C q ₁ : On from the control device 11 off controller on to 8A-8C, a command signal off q _2: oN from the control device 11 to the on-off controller 8A-8C, off confirmation of the command signal r: from photoelectric tube sensor 10 to the control device 11 Object identification signal s: limit switch Detection signal t of the object to be coated from the switches 9-1 to 9-15 to the control device 11: ON / OFF signal from the ON / OFF controllers 8A to 8C to the control device u: From the DC power source 7A Boosting state signal X to the control device 11: voltage application possible section X ₁ : boosting section, X _{2 to} X ₄ : constant voltage application possible section

Claims (2)

In slipper dip type electrodeposition coating equipment,
An electrodeposition tank for storing the electrodeposition paint;
Electrodes installed in the electrodeposition bath;
Conveying device equipped above the electrodeposition tank, comprising a hanger for suspending the object to be coated and a conveyor for transferring the hanger;
A first-stage rail provided in parallel with the conveyor in the entrance area of the electrodeposition tank, and a second-stage rail provided in parallel with the conveyor in the entire sinking area and exit tank area of the electrodeposition tank A current collecting rail for energizing the object to be coated through the hanger;
An energizing device for applying a voltage between the electrode and the current collector rail;
An identification device for identifying the type of object to be conveyed;
A position sensor disposed at a plurality of positions along the transfer path of the hanger, for detecting the arrival of the object to be conveyed;
An electrodeposition coating apparatus comprising a control device that issues a command to start and stop energization of an object to be energized to the energization device,
The second stage rail of the current collecting rail is divided into a plurality of partial rails, and in this case, the divided portion is arranged on the hanger so that one article to be coated is conveyed to one partial rail. It is installed according to the transfer pitch,
In addition, the energization device, for the second-stage rail, is configured in a circuit so that voltage can be applied independently for each divided partial rail,
In addition, the position sensor is that the object to be coated has arrived at the entry tank position or the voltage application start position, that the object has arrived at the transfer position from the first rail to the second rail of the current collecting rail, Further, each of the objects to be coated is arranged for each type of the object so as to detect that the object has arrived at the transfer position from one partial rail to the next partial rail of the second-stage rail, and the arrangement Each sensor is configured to send the detection signal to the control device when the arrival of the object to be coated is detected.
The identification device is configured to identify the type of the object to be conveyed and to send the identification signal to the control device before the object enters the electrodeposition tank. Furthermore, when the control device receives the identification signal from the identification device, the thickness of the coating film required for each type of the object to be coated, the transfer speed of the hanger, and the entrance area of the electrodeposition tank Based on the pre-input information consisting of the applied voltage boosting program and the constant voltage applied voltage values in the entire submerged area and the outgoing tank area, the energization time and the application time when the object is applied with voltage from the first rail. The energization time when the voltage is applied from each partial rail of the second stage rail is determined according to the type of the object to be conveyed, and based on each determined energization time The plurality of position sensors When each of the detection signals is received, a plurality of objects to be conveyed are energized so as to independently apply a voltage to each of the objects to be conveyed through the first-stage rail or the individual partial rails of the second-stage rail. An electrodeposition coating apparatus configured to send a start or energization stop command signal to the energization apparatus. The plurality of position sensors are:
It arrives at the position immediately before the workpiece is transferred from the first rail to the second rail of the current collector rail, and then arrives at the position after the transfer, and the workpiece is out of the second rail. It is arranged for each type of object to be detected so that it arrives at the position just before changing from one partial rail to the next partial rail and then arrives at the position after changing. When the arrival of the object to be coated is detected in each sensor, the detection signal is configured to be sent to the control device,
In addition, the control device
When a detection signal is received from the position sensor that the workpiece has arrived at a position immediately before the current collector rail is transferred from the first rail to the second rail, the second workpiece is transferred to the second workpiece. An energization start command signal is sent to the energization device to apply a voltage via the first partial rail of the step rail, and then the object to be coated is fed from the first step rail to the second step rail from the position sensor. When receiving a detection signal that it has arrived at the position after having transferred to, a command signal to stop energization is sent to the energization device to finish voltage application via the first rail, and
When a detection signal is received from the position sensor that the article has arrived at a position immediately before the second partial rail is transferred from the first partial rail to the second partial rail, the conveyed article to be conveyed The energization start command signal is sent to the energization device to be applied through the second partial rail during the energization time determined for the next partial rail, and the workpiece is removed from the second partial rail. When the determined energization time ends before the transfer to the third partial rail, a command signal to stop energization is sent to the energization device at the end, and at the same time, the object to be coated is second-stage from the position sensor. When receiving a detection signal that the position has arrived after changing from the first partial rail to the second partial rail, an energization stop command signal is sent to finish voltage application via the first partial rail. Sent to the serial power equipment, and,
When the workpiece is transferred from the second partial rail to the third partial rail, and then transferred to the subsequent partial rail, it is energized as in the case of the transfer from the first partial rail to the second partial rail described above. 2. The electrodeposition coating apparatus according to claim 1, wherein start and stop thereof are controlled.

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