JP2548780Y2 - Electrocoating equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrodeposition coating apparatus.

[0002]

2. Description of the Related Art FIG. 3 shows a schematic configuration of a conventional electrodeposition coating apparatus. In the figure, reference numeral 1 denotes an electrodeposition tank containing a coating liquid, and a plurality (for example, 5 to 6) of objects to be coated (vehicle body).
It has a size that allows W to be simultaneously immersed. A predetermined number of anode members (both not shown) to which a positive voltage is supplied are disposed in the electrodeposition tank 1. Also,
A cathode member 21 is supplied with a ground voltage from a power supply. Reference numeral 5 denotes a conveyor, and reference numeral 6 denotes a hanger which is connected to the conveyor 5 and supports the object W to be coated.
Are electrically connected. That is, the hanger 6 has a sliding contact portion that makes sliding contact with the cathode member 21.

[0003] Each object to be coated W is supported (suspended) by a hanger 6, conveyed by a conveyor 5 moving in the direction of the arrow in the figure, and immersed in the electrodeposition tank 1. Here, since the hanger 6 is in contact with the cathode member 21 by the sliding contact portion and is energized, a ground voltage is applied to the workpiece W. At this time,
In the electrodeposition tank 1, the object to be coated W becomes a cathode with respect to the anode member, and the colloidal particles such as emulsion dispersed in the coating liquid have a positive charge per se. By moving to the periphery of W and supplying electrons from the coating object W serving as a cathode, the repulsive force between the particles is reduced, and the coating of the coating object W is performed by coagulation and precipitation on the coating object W. You.

Here, in the coating of automobile bodies, it is required that the film thickness of the electrodeposition coating film be strictly controlled within a range of 20 μm to 30 μm (± 15%). If the thicknesses are not uniform, there is a problem that accurate film thickness control becomes impossible.

[0005] That is, recently, by adopting the mixed production system, objects W of different sizes such as a large car (usually a luxury car) and a small car (usually a low-priced car) are randomly placed on the hangers 6 and 6. However, in such a case, if the energization control is performed according to the film thickness of a large vehicle having a large surface area, a small vehicle having a small surface area is thickly applied, and waste of paint occurs.

In order to solve the above-mentioned inconvenience, an electrodeposition coating apparatus has been proposed in which the energization is individually controlled in accordance with the type (large or small) of the object W to be coated to perform electrodeposition coating (Japanese Utility Model Publication No. 63-63). 48696, JP-A-1-24697, etc.).

FIG. 4 shows an electrodeposition coating apparatus capable of individually controlling energization. Such an electrodeposition coating apparatus includes a cathode member 2
1 is a low-voltage rail section 22 and a plurality of divided rail sections (23
a, 23b, 23c) and a high-voltage rail portion, a discriminating means (photoelectric sensor 46) for discriminating the type (large or small) of the object to be coated W, and a detection output from the discriminating means (46). Of the plurality of cathode members 21 (mainly divided rail portions 23a, 23b, 23 constituting a high-voltage rail portion).
c) is provided with a power supply adjusting means (power supply controller 41, electromagnetic switches M1, M2, and M3) for selectively supplying power to c). Split rail portions 23a, 23b, 23c
Is formed such that its length is equal to or less than the pitch L between the hangers 6 and 6. In FIG. 4, reference numeral 45 denotes a limit switch for detecting the presence or absence of the hanger 6. Also,
11 is an anode member, 49 is a power supply. Thus, the energization controller 41 controls the opening and closing of the electromagnetic switches M1, M2, and M3 to sequentially energize the large workpiece W (A) from all the divided rail portions 23a, 23b, and 23c. The workpiece W (B) is supplied with electricity from the divided rails 23a and 23b except for the divided rail 23c, and the small workpiece W (C) is supplied with electricity only from the divided rail 23a.

[0008]

By the way, in the conventional electrodeposition coating apparatus shown in FIG. 4, a small object to be coated W (C) is used.
After stopping the current supply to the large and medium-sized objects to be coated W (A) and W (B) in front and rear,
The bipolar phenomenon occurs, and the paint that has begun to adhere to the surface of the small workpiece W is changed to the front and rear workpieces W (A) and W (A).
(B), it may be forcibly peeled off and rough skin may occur.

In view of the above circumstances, it is an object of the present invention to provide a uniform thickness of a uniform thickness for each object to be coated, even if the objects to be simultaneously immersed in a coating liquid supported by a hanger of a conveyor are not uniform. An object of the present invention is to provide an electrodeposition coating apparatus capable of forming an excellent electrodeposition coating film.

[0010]

An electrodeposition coating apparatus according to the present invention comprises: an electrodeposition tank containing a coating liquid in which an object to be coated is immersed;
A predetermined number of first electrode members connected to one end of the power supply and arranged in the electrodeposition tank, a second electrode member connected to the other end of the power supply and divided into a plurality, and connected to the conveyor. A hanger for supporting the object to be coated and electrically connecting the second electrode member and the object to be coated, a judging means for judging the type of the object to be coated, and a plurality of hangers in accordance with detection outputs from the judging means. And an energization adjusting means for selectively energizing the second electrode member. The electrodeposition coating apparatus further comprises: A shield member that can be shut off without interfering with the shield member.

[0011]

According to the present invention having the above-described structure, in the case where the energization adjusting means individually adjusts the energization of each of the irregularly sized objects to be coated simultaneously immersed in the coating liquid in the electrodeposition tank,
For example, even after the energization of a small object to be coated is stopped and the energization of the front and rear objects is performed, the bipolar phenomenon does not occur because the shield member is provided between the objects to be coated. That is, since the electric field in the front and rear objects does not reach the small object by the shield member, the paint applied to the object is not pulled toward the front and rear objects.

Therefore, even if the substrates to be simultaneously immersed in the coating liquid while being supported by the hanger of the conveyor are irregular in size, a uniform electrodeposition coating film having a constant thickness can be formed on each substrate with high quality. Can be formed.

[0013]

FIG. 1 is a view for explaining an embodiment of the present invention.
FIG. 2 is a diagram showing the shape of the shield member.

An embodiment of the present invention will be described below with reference to the drawings. This electrodeposition coating apparatus has a basic configuration [electrodeposition tank 1, conveyor 5, hanger 6, anode member 11, cathode member 21 (low-voltage rail portion 22, divided rail portions 23a and 23b constituting high-voltage rail portion, 23c), energizing controller 4
1, electromagnetic switches M1, M2, M3, etc.) are conventional examples (FIG. 4)
Between the objects to be coated [W (A), W (B), W (C), etc.] immersed in the coating liquid in the electrodeposition tank 1 [W (A) ), W (B), W (C), etc.].

The same or similar components as those in the conventional example (FIG. 4) are denoted by the same reference numerals, and detailed description thereof will be omitted.

Here, the shield member 31 is made of a material to be coated [W (A), W) immersed in a coating liquid in the electrodeposition tank 1.
(B), W (C), etc.].
(B), W (C), etc.]. In the present embodiment, the shield member 31
Are attached to the hangers 6, 6, 6,... That support the workpieces W (A), W (B), W (C).
(B), W (B), W (C) ... are connected so as to be cut off. As shown in FIG. 2, the shield member 31 is curved so as to protrude in the transport direction (the direction of the arrow in the figure) so as to reduce the fluid resistance.

Each object to be coated [W
(A), W (B), W (C)...] Do not become rough due to the bipolar phenomenon.
W (C)...], The shield member may be formed in any manner.

For example, the shield member may be constituted by a pair of shield members each having a double door structure provided at a predetermined pitch in the electrodeposition tank 1. Each of the pair of shielding members is rotatably provided at a predetermined position on both inner side walls of the electrodeposition tank 1 and is positioned by a spring member so as to close a movement path of the object to be coated in a normal state. In some cases, the spring member is formed so as to rotate in the opening direction while elastically deforming and permit the passage of the object to be coated.

Further, the shield member may be constituted by a predetermined number of shield members provided so as to be able to enter and exit the electrodeposition tank 1. Each shielding member is provided so as to shut off between the objects to be conveyed in the coating liquid, and to be able to exit the tank and retreat upward when passing through the object.

The energization controller 41 is provided with the electrodeposition tank 1.
A switch signal of a detection switch (limit switch) 45 for detecting the presence of the hanger 6 transferred to the tank entrance side, and the presence and size of the object placed on the hanger 6 when the switch signal is output. The rails 23a, 23b, 23a, 23b, on which the hangers 6 slide sequentially, based on the detection signal of the photoelectric sensor 46 for determining the length and the conveyor synchronization signal.
The configuration is such that the energization control of 23c is performed. That is, when the switch signal of the detection switch 45 is input, the energization controller 41 starts counting of the conveyor synchronization signal, and each hanger 6 separates the divided rail portions 23a, 23a.
The time to be sequentially slid into contact with 3b and 23c is determined, and the presence / absence and size of the object placed on each hanger 6 are determined based on the detection signal input from the photoelectric sensor 46.

When the object to be coated W is not placed on the hanger 6, the hanger 6 is connected to the low-voltage rail section 2.
2, the control signals CP1, CP2, and CP3 for opening the electromagnetic switches M1, M2, and M3 are sequentially output at a predetermined timing to energize the divided rail portions 23a, 23b, and 23c with which the hanger 6 slides. Are sequentially stopped.

A large object to be coated W (A) is attached to the hanger 6.
Is mounted, control signals for closing the electromagnetic switches M1, M2, and M3 are sequentially output to output the hanger 6
Are sequentially energized to all of the divided rail portions 23a, 23b, and 23c that are in sliding contact.

The hanger 6 has a medium-sized coated object W (B).
, The control signals CP1 and CP2 for closing the electromagnetic switches M1 and M2 and the control signal CP3 for opening the electromagnetic switch M3 are sequentially output to output the hanger 6.
Are sequentially energized to the divided rail portions 23a and 23b with which
The energization to the divided rail portion 23c is stopped.

Further, a small object to be coated W is attached to the hanger 6.
When (C) is mounted, the control signal CP1 for closing the electromagnetic switch M1 and the control signals CP2 and CP3 for opening the electromagnetic switches M2 and M3 are sequentially output to energize only the divided rail portion 23a. The power supply to the other divided rail portions 23b and 23c is sequentially stopped.

Next, the operation of this embodiment will be described.
The electric current adjusting means (41, M1) is applied to each of the objects (W (A), W (B), W (C),...) Of irregular sizes which are simultaneously immersed in the coating solution in the electrodeposition tank 1. M2, M3), when the energization is individually adjusted, for example, a small workpiece W
After the energization of (C) is stopped, the front and rear workpieces W
(A) and W (B), the shield member 31 is interposed between the objects to be coated W (A) and W (C) and between W (C) and W (B). Therefore, the bipolar phenomenon does not occur. That is, the front and rear objects to be coated W (A), W (B)
Since the electric field in the above does not reach the small object to be coated W (C) by the shield member 31, the paint applied to the object to be coated W (C) is applied to the front and rear objects to be coated W (A) and W (B). There is no pulling at it.

Thus, according to this embodiment, the electrodeposition tank 1
To be coated [W (A), W
(B), W (C),...
W (B), W (C),...], The shield member 31 is provided so that the shield member 31 can be shielded without interfering with the coating material, and is supported by the hanger 6 of the conveyor 5 and simultaneously immersed in the coating liquid. Even if the objects [W (A), W (B), W (C),...] Are not uniform in size, each object to be coated [W (A), W (B), W
(C), ...], a uniform electrodeposition coating film having a constant thickness can be formed with high quality.

Further, since the shield member 31 is connected to the hanger 6, each object to be coated [W (A), W (B), W (C). Thus, a uniform electrodeposition coating film having a constant thickness can be formed with high quality.

Further, since the shield member 31 is formed to be curved so as to protrude in the transport direction, the fluid resistance is reduced and the transport in the coating liquid can be carried out smoothly.

[0029]

According to the present invention, there is provided a structure in which a shield member capable of intercepting each of the objects to be coated immersed in the coating liquid in the electrodeposition tank without interfering with each of the objects to be coated is provided. Therefore, even if the objects to be simultaneously immersed in the electrodeposition coating liquid placed on the conveyor hanger are uneven in size, a uniform electrodeposition coating film of a constant thickness is formed on each object with high quality. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an embodiment of the present invention.

FIG. 2 is a view showing the shape of a shield member.

FIG. 3 is a view for explaining a schematic configuration of a conventional electrodeposition coating apparatus.

FIG. 4 is a view for explaining a conventional electrodeposition coating apparatus which can be individually energized.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrodeposition tank 5 Conveyor 6 Hanger 11 Anode member 21 Cathode member 22 Low voltage rail part 23a, 23b, 23c Split rail part 31 Shield member 41 Electricity controller (electricity adjustment means) 46 Photoelectric sensor (discrimination means)

Claims (1)

(57) [Scope of request for utility model registration] An electrodeposition tank containing a coating liquid into which an object to be coated is immersed; a predetermined number of first electrode members connected to one end of a power supply and disposed in the electrodeposition tank; A second electrode member connected to the end and divided into a plurality of parts, a hanger connected to the conveyor and supporting the object to be coated and electrically connecting the second electrode member and the object to be coated; An electrodeposition coating apparatus comprising: a determination unit configured to determine a type of an object; and an energization adjustment unit configured to selectively energize the plurality of second electrode members in accordance with a detection output from the identification unit. An electrodeposition coating apparatus, comprising a shield member capable of blocking between objects to be coated immersed in a coating liquid in a coating tank without interfering with the respective objects to be coated.