JPH06218308A - Coating method and coating device - Google Patents

Abstract

PURPOSE:To provide a coating method by which to paint a large quantity of coating objects efficiently and simply without requiring manual labor, and a coating device using this method. CONSTITUTION:Coating objects (automotive parts) H are loaded in a cage-like container 1, and the cage-like container 1 is immersed in a paint tank 2 during coating operation by lifting-up of the paint tank 2 by a paint tank lift device 12. After that, the paint tank is lowered to allow the cage-like container 1 to rotate forward and backward in the paint tank so that a surplus droplet of paint is recovered into the paint tank 2. Further, the coating object H coated by immersion in the cage-like container 1 is allowed to fall to the surface of a reticular belt conveyor 3 and deposit. Next, the coating object H on the belt conveyor 3 is heated and baked, and this baked coating object H is loaded in the cage-like container 1 to be immersed sequentially. After this step, the paint tank is hoisted and rotated so that the coating object is baked thus undergoing a total of two rounds of coating and baking steps. Both cage-like container 1 and paint tank 2 are stored in a single coating chamber where a thermostat 6 and a supersonic humidifier 7 are arranged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating method capable of simply and efficiently coating a large amount of objects to be coated, and a coating apparatus therefor. INDUSTRIAL APPLICABILITY The present invention is used for coating automobile parts such as muffler hangers, stays or brackets.

[0002]

2. Description of the Related Art As a conventional method for coating an article to be coated, a method is known in which each article to be coated is suspended, immersed in a coating tank, pulled up, dried and baked.

[0003]

However, in this coating method, it is difficult to coat a large amount of the object to be coated efficiently, and the apparatus becomes large in size.

The present invention has been made in order to solve the above problems, and provides a coating method capable of easily and efficiently coating a large amount of an object without manpower, and a coating apparatus therefor. The purpose is to

[0005]

According to the first aspect of the present invention, there is provided a basket-shaped container in which a plurality of objects to be coated are placed, and the basket-shaped container is immersed in the paint in a paint tank. In the paint tank and on the surface of the paint, and the basket-shaped container is rotated in the forward or reverse direction or in one direction to collect the residual drop paint in the paint tank, and then dip in the basket-shaped container. Place the coated object by dropping it on a mesh belt conveyor,
The article to be coated on the belt conveyor is heated and baked, and then the baked article to be coated is placed in the basket-like container, successively immersed as described above, and the basket-like container is pulled up. It is characterized in that it is rotated and baked to perform coating and baking twice in total.

A water-based inorganic coating material may be used as the "coating material", and heating in the baking step may be performed at 80 to 120.degree. C. and then at 180 to 220.degree. Further, as a method of immersing the basket-shaped container in the coating material in the coating material tank, a method of moving the coating material tank up and down or a method of moving the basket-shaped container up and down can be used. Furthermore, after the immersion-coated object is discharged from the basket-like container, when the basket-like container is returned to the paint surface in the paint tank, the basket-like container is generated from an ultrasonic humidifier. It is also possible to apply steam to drop off the paint adhering to the basket-like container and to collect the fallen paint in the paint tank.

The coating apparatus according to the fifth aspect of the present invention is a basket-shaped container for containing a plurality of objects to be coated, and a paint tank for containing a paint and dipping the object-to-be-coated in the basket-shaped container. And a rotation device for rotating the forward and backward directions or one direction around the central axis of the basket-like container to shake off excess paint adhering to the object to be coated, and the basket-like container at a predetermined position. A moving device for moving up to, a basket-shaped container for storing the coated object is reversed and the inverting device for dropping and removing the coated object from the basket-like container, and the dropped device. A net-like belt conveyor that carries an object to be coated and is conveyed to a baking oven, and the baking oven for heating and baking the object to be coated placed on the belt conveyor. Is characterized by.

As a device for immersing the object to be coated contained in the basket-like container, a device for raising and lowering a base or the like for fixing the basket-like container (for example, an elevating device in combination with a centrifugal rotating device is used). And the like), but as shown in the fifth invention, a paint tank elevating device for elevating the paint tank can also be used. The "heating furnace" is 80 to 12
First heating zone to heat to 0 ° C, then 180-220
It can be set as the two-stage heating furnace provided with the 2nd heating area which heats to ° C. Above "basket container" and above "paint tank"
Is contained in one coating chamber, a temperature controller and an ultrasonic humidifier are arranged in the coating chamber, and the vapor generated by the ultrasonic humidifier discharges the dip-coated object to be coated. It is possible that the paint applied to the basket-like container is dropped off and the fallen paint is collected in the paint tank.

[0009]

In the present invention, a plurality of objects to be coated are placed in a basket-like container, the basket-like container is dipped in the paint in the paint tank, and the plurality of objects to be dipped and coated are reticulated with a mesh belt. Place on a conveyor all together and heat at the same time. Therefore, a large amount can be simultaneously applied and cured, which is excellent in coating efficiency and mass production. Further, in the present invention, since the objects to be coated come into contact with each other or the belt conveyor and the object to be coated, uniform coating of the coating material (uniform coating film formation) is insufficient in the first coating at these contact points. However, in the present invention, the second coating is further repeated, and in this case, it is unlikely that the contact is made at the same point as the contact point in the first coating. Without coating, the entire surface of the coated object can be successfully coated. Further, since the basket-shaped container is rotated in the paint tank to remove the residual paint by centrifugal force, a substantially uniform application can be performed, and the residual paint can be collected in the paint tank, and the paint recovery efficiency is excellent.

When a water-based inorganic coating material is used as the coating material and heating is performed at 80 to 120.degree. C. and then at 180 to 220.degree. A film can be formed. After discharging the coating object that has been applied by immersion from the basket-like container,
When the basket-like container is returned to the surface of the paint in the paint tank and steam generated from the ultrasonic humidifier is applied to the basket-like container, the paint adhered to the basket-like container is easily dropped off and the drop-off paint is applied. Can be reliably collected in the paint tank.
Further, when the basket-shaped container and the paint tank are housed in one coating chamber and a temperature controller is arranged in the coating chamber,
Since the temperature and humidity are stable, the physical properties of the coating do not fluctuate with time, and a stable coating film can be formed at any time. Further, it suffices to control the temperature of only this small paint chamber, and it is not necessary to control the temperature of the entire paint factory as in the conventional case, so that the electricity bill and the like can be greatly saved.

[0011]

EXAMPLES The present invention will be specifically described below with reference to examples. (1) Coating Device As shown in FIGS. 1 and 2, the coating device used in the present embodiment is a basket-shaped container (about 600 mmφ × 600 mm) 1, a paint tank (800 mmφ × 1000 mm) 2 for containing paint,
Mesh belt conveyor (length; about 40-50m, width;
1.2-1.5 m) 3, baking oven (length; 35-45 m, which is slightly shorter than the length of the belt conveyor) 4, basket-shaped container moving device 9, reversing device 10, rotating device 11, and paint tank lifting device 12 Equipped with. And the basket-shaped container 1 and the paint tank 2 are
It is housed in one coating chamber 8, and the temperature controller 6 and the ultrasonic humidifier 7 are arranged above the coating chamber 8. When the basket-shaped container 1 from which the object to be coated which has been dip-coated is discharged is placed on the surface of the paint, the steam generated by the ultrasonic humidifier 7 is applied to the basket-shaped container 1 and adheres to the basket-shaped container 1. The paint that has fallen off can be dropped off and the paint that has dropped off can be collected in the paint tank 2.

As shown in FIGS. 2 and 1, the basket-like container 1 accommodates a plurality of objects to be coated (for example, a muffler hanger, a stay, a bracket, or the like corresponding to 30 to 50 kg). A frame portion 1a protruding laterally is formed above the basket-shaped container 1.
The gripping, fixing, or locking when moving and reversing is secured. The moving device 9 moves each of the position where the article to be coated is put in the basket-like container → the window 81 of the paint chamber → above the paint tank 2 → the position out of the window of the paint chamber (before discharging the article to be coated) It is a device for performing. For example, as shown in FIG. 2, in order to move the article to be coated H from the position where it is put into the basket-shaped container 1 to the side of the paint chamber window 81, a storage box that stores the basket-shaped container 1 at the tip of the arm 91 that is rotated This is done by attaching 92 and rotating this arm 91. Next, the basket-shaped container 1 which has reached the window 81 is provided with a rail (2
Book, not shown. ), The frame portion 1a of the basket-shaped container 1 is inserted and pushed out, so that the basket-shaped container 1 is sent out along the rail to above the paint tank. Then, after the immersion and the centrifugal rotation, the rail is used in the same manner to make the cage 1
Is pulled out to be arranged near the window 81 of the paint chamber 8 and outside thereof.

The paint tank elevating / lowering device 12 is for raising and lowering the paint tank 2 to immerse an object to be coated in the paint or take it out of the paint, and a base 122 on which the paint tank 2 is placed.
And a pair of chains (belts) 121 for raising and lowering the base. The drive device for the chain 121 is not shown. The rotating device 11 is for rotating the basket-shaped container 1 in the forward and reverse centrifugal directions about the center axis of the basket-shaped container, and rotates the mount 111 for mounting the basket-shaped container 1. This speed is about 200
The rpm and the rotation time are 15 seconds each in the forward and reverse directions. The rotary drive device is not shown. This makes it possible to shake off the excess paint that has adhered to the object to be coated. And
This rotation is performed at a position in the upper half of the paint tank 2 (a position in the paint tank and on the paint surface). The reversing device 10 fixes the basket-shaped container 1 pulled out to the outside of the window of the paint chamber with fixing claws 10b as shown in FIG. 2, and then rotates (rotates) the rotating shaft 10a. By doing so, the basket-shaped container is inverted, and the article to be coated contained therein is dropped and discharged.

Aqueous inorganic paint ("Stain Guard" (registered trademark, manufactured by Oshima Kogyo Co., Ltd.) is poured into the paint tank 2 in a substantially lower half thereof. Further, the belt conveyor 3 has a metal mesh (mesh; about 5 meshes). Is about 20 mm) and is arranged such that when the basket-shaped container for storing the coated object is inverted and the object-to-be-coated falls from the basket-shaped container, the object-to-be-coated is placed. Then, the belt conveyor 3 is moved into the baking furnace 4 and is exposed to the outside from the other end side of the baking furnace 4. From the exposed end portion, the first baked object is exposed. It is connected to a container / moving trolley 5 for receiving a coated object, and the object to be coated (primary coated object) loaded on the container / moving trolley 5 is a storage box 92 of the moving device 9 shown in FIG.
To the vicinity of the container, and then the container / moving carriage 5 is placed (locked) on the lift as it is, and the primary coating material is reloaded in the storage box 92 and reloaded into the basket-shaped container 1. .

The heating furnace 4 is a two-stage heating furnace having a first heating region 41 for heating to 80 to 120 ° C. and a second heating region 42 for subsequently heating to 180 to 220 ° C. This heating is performed by supplying hot air of a predetermined temperature (the supply fan is not shown). In order to heat efficiently, it is preferable to apply hot air intensively to the lumps of the coated objects, which are collected together. In this case, this can be done by moving the blower opening along with the movement of the article to be coated.

(2) Coating Method In this example, the above-mentioned coating apparatus was used to coat an object to be coated as follows. That is, first, the container / movable carriage 5 containing an unpainted object (unpainted object; a plurality of degreased muffler hangers, stays or brackets equivalent to 30 to 50 kg) H is placed on the lift and moved. The unpainted object is moved to the housing box 92 shown in FIG. 2 (in FIG. 2) by locking it at a predetermined height so that it can be easily moved. Then, the moving device 9
The basket 91 is rotated to rotate the armor 91 of the
Move it to the edge (in FIG. 2). Next, the frame portion 1a of the basket-shaped container 1 is inserted into the rails (2) for feeding the basket-shaped container to the upper side of the paint tank, and the basket-shaped container 1 is extruded,
It was sent above the paint bath (Fig. 2). After that, the paint tank elevating device 12 was operated to raise the paint tank 2, and the entire basket-shaped container was immersed in the paint. After dipping, this paint tank 2
Was lowered to a position where the bottom of the basket-shaped container was above the paint surface, and the basket-shaped container 1 was centrifugally rotated in the paint tank 2 in the forward and reverse directions (each about 200 rpm × 15 seconds). As a result, the excess paint that had adhered to the object to be coated was shaken off. In this case, the residual paint is collected in the paint tank 2.

Thereafter, the paint tank 2 was further lowered, and the basket-shaped container 1 was completely ejected from the paint tank 2. Next, one end of this basket-shaped container was hooked, and the same rail was used to pull it out to the front and move it out of the window 81 of the paint chamber 8 (in FIG. 2). Further, one end of the frame portion 1a of the basket-shaped container pulled out to the outside is fixed and locked by the fixing claw 10b, and then the rotating shaft 10a is rotated (rotated) to the right to rotate the basket. The container is inverted (hatched portion in FIG. 2), and the article to be coated contained therein is dropped downward (in FIG. 2). The article to be coated H was dropped onto the belt conveyor 3 located below it. The dropped object H to be coated is accumulated.

After that, the belt conveyor 3 was conveyed so that the article H to be coated was conveyed into the heating furnace 4. By this transportation, 5 to 10 minutes in the first heating area (about 100 ° C.),
It was heated in the second heating region (about 200 ° C.) for 10 to 20 minutes to be baked and cured to form the first coating film. These were further transported, and all of them were dropped and stored in the container / movable carriage 5. Then, the coated object loaded on the container / moving carriage 5 is
The moving device 9 shown in FIG. 2 is moved to a position close to the storage box 92, and the container / movable carriage 5 is directly placed on a lift and locked at a predetermined height to store the object to be coated in the storage box 9.
It was re-introduced into the basket-shaped container 1 in 2. The inverted basket-shaped container is returned to its original position (FIG. 2), and this basket-shaped container is loaded in the storage box 92 while another basket-shaped container is immersed and rotated. Have been moved to the positions (and in FIG. 2). Furthermore, the above-mentioned steps were repeated to perform the second coating and baking.

(3) Effect of Example The object to be coated that had been baked twice had no paint peeling portion, and an inorganic coating film (thickness: 15 to 20 μm) was uniformly formed. The result of the durability (cold heat resistance) test was acceptable. This test includes a combined cycle test method, that is, −
100 cycles repeated at 20 ° C, 150 ° C, 250 ° C, 350 ° C, 450 ° C and 550 ° C, then J
A peeling test was performed by the IS-5400 cross-cut tape peeling method. This pass judgment is 100/100 (Crossboard)
There was no peeling and no discoloration of the coating film. The result of the corrosion resistance test was also acceptable (no rust was generated). For this corrosion resistance test, 0.5% concentration and 3
Spray 5 ° C. saline for 2 hours, then dry at 60 ° C. for 4 hours, then dry at 95% humidity and 50 ° C. for 2 hours.
This was exposed for a period of time, and this 1 cycle was repeated 50 times, and the presence or absence of rust (rust within 3 mm after cross-cut) was judged.

Also, it is possible to coat a large amount of objects at a time,
It was very efficient. Further, when the steam generated from the ultrasonic humidifier was gently applied to the basket-like container, the paint adhering to the basket-like container fell into the paint tank. Therefore, this basket-like container could always be used in a fresh state. In addition, a total of two people, one person near the window of the paint room and one person to carry the article to be dropped from the belt conveyor, was sufficient. Further, since the container and the movable carriage are used, it is very convenient for transporting an article to be coated (uncoated article or primary coated article).

The present invention is not limited to the specific examples described above, and various modifications may be made within the scope of the present invention depending on the purpose and application. That is,
The size and shape of the basket-like container (the cross-section may be not only round but also square, etc.), the size of the mesh of the basket, etc. are not particularly limited. Also, the size and shape of the paint tank are not particularly limited,
Any material can be used as long as it can immerse the article to be coated placed in the cage. Further, the rotating device, moving device, reversing device, and paint tank elevating device for the basket-like container described above are different mechanisms as long as they can rotate, move, invert, and elevate the paint tank. It may consist of The heating means of the heating device may not be hot air as in the above embodiment, but may be any other known means (electrical heating, ultrasonic heating, etc.). Further, the heating temperature and the number of heating stages are variously selected depending on the type of paint used and the like. The method of transferring the coating object falling from the belt conveyor, particularly the primary coating material after the first baking is transferred to the second coating step, is other than the transportation by the container / moving carriage / forklift as shown in the above embodiment. It is also possible to perform automatic conveyance by connecting a belt, automatic operation by a computer, and the like. Further, a container for containing the object to be coated falling from the belt conveyor can be used together with the basket-like container.

[0022]

EFFECTS OF THE INVENTION By using the coating method of the present invention and the coating apparatus of the present invention, a large amount of objects can be coated easily and efficiently without manpower.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing a coating method and a coating apparatus used in Examples.

FIG. 2 is a schematic explanatory view of a cage-shaped container moving device and a reversing device used in Examples.

[Explanation of symbols]

1; basket-like container, 2; paint tank, 3; belt conveyor, 4;
Baking oven, 5; container and moving carriage, 6; temperature controller, 7; ultrasonic humidifier, 8; coating chamber, 81; coating chamber window, 9; moving device, 10; reversing device, 11; rotating device, 12: Paint tank lifting device.

Claims (8)

[Claims] 1. A plurality of objects to be coated are placed in a basket-like container, the basket-like container is immersed in the paint in a paint tank, and the basket-like container is in the paint tank and on the paint surface. The basket-shaped container is pulled up and rotated in the forward or reverse direction or in one direction to collect the residual paint in the paint tank, and thereafter, the dip-coated object in the basket-shaped container is placed on a mesh belt conveyor. It is dropped and placed, and the article to be coated on the belt conveyor is heated and baked, and then the baked article to be coated is put into the basket-like container and sequentially immersed as described above. A coating method, wherein the basket-shaped container is pulled up, rotated, and baked to perform coating and baking twice in total. 2. The coating method according to claim 1, wherein the method of immersing the basket-shaped container in the paint in the paint tank is a method of raising and lowering the paint tank or a method of raising and lowering the basket-shaped container. 3. A water-based inorganic paint is used as the paint,
The coating method according to claim 1 or 2, wherein in the baking step, heating is performed at 80 to 120 ° C and then heating is performed at 180 to 220 ° C. 4. The dip-coated article to be coated is discharged from the basket-shaped container, the basket-shaped container is returned to the paint surface in the paint tank, and the basket-shaped container is generated by an ultrasonic humidifier. The coating method according to any one of claims 1 to 3, wherein steam is applied to remove the paint adhering to the basket-like container, and the fallen paint is collected in the paint tank. 5. A basket-shaped container for containing a plurality of objects to be coated, a paint tank for containing a coating material and dipping the object to be coated contained in the basket-shaped container, and the basket-shaped container A rotation device for rotating the forward and backward directions or one direction around the central axis to shake off excess paint adhering to the object to be coated, and a moving device for moving the basket-shaped container to a predetermined position. And a reversing device for reversing the basket-shaped container for storing the coated object to drop and remove the coated object from the basket-like container, and placing the dropped object to be coated. A coating apparatus comprising: a net-shaped belt conveyor that is conveyed together with a baking oven; and the baking oven for heating and baking the object to be coated placed on the belt conveyor. 6. The coating apparatus according to claim 5, wherein the device for immersing the object to be coated contained in the basket-shaped container is a paint tank elevating device for elevating the paint tank. 7. The heating furnace is a two-stage heating furnace comprising a first heating zone for heating to 80 to 120 ° C. and a second heating zone for heating to 180 to 220 ° C. thereafter. The described coating equipment. 8. The basket-shaped container and the paint tank are housed in one coating chamber, a temperature controller and an ultrasonic humidifier are arranged in the coating chamber, and steam generated by the ultrasonic humidifier is immersed in the coating chamber. 8. The coating composition is applied to the basket-shaped container from which the coated object has been discharged to remove the coating material adhering to the basket-shaped container and to collect the removed coating material in the coating material tank. Painting equipment.