JP2582623B2 - Coating curing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a coating for curing a coating film composed of a synthetic resin paint (hereinafter, referred to as a urethane-based coating) which forms urethane bonds in the coating film by curing. The present invention relates to a film curing device.

(Prior art) Curing of a urethane-based paint is most commonly performed by heating, but curing by heating requires a large amount of exhaust treatment equipment for removing paint stains, solvents, and the like present in the exhaust gas. There is a problem that a load is applied and the cost for heating is high. Further, it cannot be applied to a material such as a woodwork which is deformed or deteriorated by heating. Therefore, such a material has been cured when left at room temperature.
However, since curing at room temperature takes a very long time, productivity becomes low, and strict management must be performed so that dusts and the like do not adhere while standing.
There is a problem in equipment and workability.

As a curing method for solving such a problem, Japanese Patent Publication No. 53-19038 describes a method of curing in an amine or ammonia atmosphere. In this method, amines and ammonia emit a very strong odor, which has a serious adverse effect on the working environment, and when workers inhale these substances, it is not desirable from a health point of view. The lower curing is desirably performed in a closed room. However, in industrial use, coating with urethane-based paint requires the steps of coating, curing and post-curing to be integrated into the same transport system and must be performed continuously. A mouth and an outlet are formed. This causes a problem that air in the curing chamber leaks out of the chamber.

In order to prevent the amine and ammonia from leaking out of the curing chamber, attempts have been made to provide sealing mechanisms at the entrance and exit of the curing chamber. FIG. 4 is a view of the seal mechanism 35 of the coating film curing apparatus described in Japanese Patent Publication No. Sho 62-31989 as viewed from outside the curing chamber. The sealing mechanism 35 includes a partition plate 31 cut out substantially in accordance with the shape of the article to be processed, and the partition plate 31.
An intake nozzle 32 communicates with an intake duct provided near 31. Since the air including the amine and ammonia in the curing chamber near the carry-in and carry-out ports and the air outside the curing chamber are constantly sucked from the intake nozzle 32, the leakage of the air in the curing chamber is suppressed.

(Problems to be Solved by the Invention) However, in the above-mentioned sealing mechanism, since the shape of the cutout portion of the partition plate 31 is determined, the shape and size of the processed object to be processed are limited. Therefore, as in recent years, when the demand for products is small and many kinds, and products having different sizes or shapes must be continuously processed, the coating film curing apparatus 29 having the above-described sealing mechanism 35 is used. It was difficult to respond. The above sealing mechanism 35
In this case, if the partition plate 31 is slidable or rotatable, it can cope with a change in the shape of the article to be processed to some extent. That is, when the article to be processed is small, the partition plate 31 is closed to reduce the opening area of the carry-in port or the carry-out port, and when the article to be processed is large, the partition plate 31 is opened to increase the opening area, Ensure that the article to be processed can pass through. However, even when the workpiece is small, the suction nozzle
Since the suction port 33 of 32 is located near the side wall 34 of the carry-in or carry-out port, in order to form an air seal by sucking gas from the suction port 33, the amount of suction is reduced in the same manner as in the case where the article to be processed is large. Must be large.

This will be described with reference to the schematic diagram of FIG. This figure is a diagram showing a state of an air flow near a carry-in or carry-out port of the conventional coating film curing apparatus. As shown in the figure, when a relatively small workpiece 20 is cured, the partition plate 31 is hardened.
By narrowing the gap therebetween, leakage of air containing amine or ammonia in the curing chamber can be suppressed to some extent. However, in order to completely prevent air leakage, an air seal must be formed at the carry-in port. However, since the intake port 33 of the intake nozzle 32 is near the side wall 34, only a small amount of intake air sucks only the air D around the intake port 33, and a complete air seal is not formed. Therefore, a part C of the air in the curing chamber leaks. As is evident from this example, the required intake air amount is almost the same as when the article to be processed is large even when the article to be processed is small.

If the amount of intake air is large, the consumption of amine or ammonia increases, the amount of exhaust treatment increases, the cost for driving the exhaust treatment device increases, and the durability of the device is shortened. The processing cost as a whole increases. Therefore, it is desirable to minimize the intake air amount.

Therefore, the present invention provides a film curing method that can continuously process products having different shapes or sizes, and can completely prevent leakage of amine or ammonia in the curing chamber with a minimum amount of intake air. It is intended to provide a device.

(Means for Solving the Problems) In order to achieve the above object, a coating film curing apparatus of the present invention comprises a curing chamber kept under an atmosphere of amine or ammonia, whereby a urethane bond is formed in a coating film by curing. In a coating film curing apparatus for curing a coating film of a synthetic resin paint to be formed, near a carry-in port and a carry-out port in a curing chamber, an intake nozzle for communicating with an intake duct and sucking a surrounding gas is provided. A partition plate for shielding a part of the carry-in port and the carry-out port is provided on the hardening chamber side from the suction nozzle, and the suction port of the suction nozzle is provided on a workpiece to be cured with a coating film. An intake port moving mechanism that is provided so as to be able to approach and separate from the workpiece, and that allows the intake port to approach and separate from the article to be processed, thereby shielding the entrance and exit with a desired area. Features.

When the article to be processed is suspended and conveyed, the suction nozzle is provided at three locations on the left, right, left and right sides of the article to be processed and toward the article to be processed. It is preferable to provide such that the intake port is opened. in this case,
Of the suction nozzles, the suction nozzles on both the left and right sides of the article to be processed are hollow plate-like bodies having a height substantially equal to the height of the carry-in or carry-out port.

More preferably, a bellows is provided between the intake port of the intake nozzle and a portion communicating with the intake duct, so that the bellows can be extended and contracted. In this case, the intake port is fixed to a pulley on the rail, and is movable by a cylinder. On the other hand, the end of the intake nozzle on the side communicating with the intake duct is fixed. Therefore, the intake port approaches and separates from the article to be processed by the intake port moving mechanism including the bellows, the cylinder, the rail, and the pulley.

The suction nozzle below the article to be processed is a hollow plate-like body having a width substantially equal to the width of the carry-in port or the carry-out port, and one end is opened toward the article to be treated, and the other end is used for suction. Communicate with duct. More preferably, a stretchable bellows is provided between an intake port of the intake nozzle and a portion communicating with the intake duct, and a tip end of the intake port can be moved up and down by a jack. The tip of the shaft is fixed. Therefore, the suction port portion approaches and separates from the article to be processed by the suction port moving mechanism including the bellows, the shaft, and the jack.

The partition plate provided on the curing chamber side from the suction nozzle,
For example, by making it slidable or rotatable,
It is preferable that the width of the gap between the partition plates can be changed. Further, a partition plate can be provided on the carry-in and carry-out sides of the suction nozzle. In this case, the partition plate is also configured such that the gap between the partition plates can be changed like the above-mentioned partition plate, and further, the gap between the partition plates on the curing chamber side is changed to the gap between the partition plate on the entrance and the exit side. Make it narrower.

Further, preferably, a device for automatically detecting the size of the object to be processed, for example, a photoelectric tube device, an image sensor, or the like is provided in front of the entrance of the curing chamber, and information detected by the device is sent to the central control device. Feeding, controlling the mechanism for moving the intake port and the mechanism for opening and closing the partition plate by the control device,
The movement of the intake port and the movement of the partition plate are automatically performed.

In the coating film curing apparatus of the present invention, the position of the suction port of the suction nozzle is changed according to the size of the article to be processed, and preferably, the gap between the partition plates is changed to transfer the article to be processed. Then, the coating film is cured.

(Function) In the coating film curing apparatus of the present invention, the suction nozzle can be moved closer to or away from the processing object depending on the size of the processing object. Because the exit can be shielded to any area,
Objects to be processed having different shapes and sizes can be continuously processed.

Moreover, by blocking the carry-in and carry-out ports, the outlet area of the air containing amine or ammonia in the curing chamber can be minimized, and the intake nozzle is brought close to the position closest to the outlet section. Therefore, when processing a relatively small workpiece, an air seal is formed even if the amount of intake air is reduced. This will be described with reference to FIG. 5 showing the state of the airflow near the carry-in section of the present invention. In FIG. 5, the inlet is located near the center for processing a small workpiece. Therefore, the opening area of the carry-in port is reduced, the carry-in port portion is prevented, and the air seal B is formed with a small amount of intake air.

(Examples) Hereinafter, the present invention will be described in more detail with reference to examples.

FIG. 1 is a top view of a coating film curing apparatus 1 of the present invention. The coating film curing device 1 includes an air supply device 3 for supplying amine or ammonia vapor into a curing chamber 2, and an exhaust port.
An exhaust duct 11 provided with 12 and a conveyor 8 for transporting the article to be treated 20 are provided. Air in the curing chamber 2 leaks to the outside near the entrance 4 and exit 5 in the curing chamber 2. A steam generator 7 for generating amine or ammonia outside the curing chamber, a filter / purifier 13, an air supply duct 9, an exhaust duct 11,
And an intake duct 22.

The air supply device 3 is provided on both side walls 29 in the curing chamber 2, and fins 10 are provided in the air supply portion. The air supply device 3 communicates with the steam generator 7 through an air supply duct 9, and amine or ammonia vapor generated by the steam generator 7 passes through the air supply duct 9 to the air supply device 3. It is supplied and exits into the curing chamber 2 from the air supply section where the fin 10 is formed.

The exhaust duct 11 goes out of the curing chamber 2 from above the curing chamber 2 and communicates with the filtration and cleaning mechanism 13. The air outlet 12 is
The exhaust duct 11 is open downward at both sides of the conveyor 8.

As shown in FIG. 2, the seal mechanism 6 provided on the carry-in port 4 side
Will be described. Note that the seal mechanism 6 on the side of the carry-out port 5 has the same configuration. The sealing mechanism 6 includes suction nozzles 14, 15,
16 and partition plates 17a and 17b. Intake nozzles 14, 15
Is provided on the side wall near the carry-in port 4 in the curing chamber 2, and the suction nozzle 16 is provided on the bottom surface at a position slightly closer to the carry-in port 4 than the suction nozzles 14 and 15. Each of the suction nozzles 14, 15, 16 is a hollow plate-like body partially formed with a bellows 26, and the end on the side of the article to be processed 20 is open.
Is formed. The opposite end communicates with an intake duct 22 that extends to the outside of the curing chamber 2. The partition plates 17a, 17b are provided on the inner side of the curing chamber from the suction nozzle, and the partition plates 17a, 17b
17b is provided on the carry-in or carry-out side of the intake nozzle. These are each freely rotatable,
By opening and closing, the size of the gap between the partition plates can be changed.

A rail 18 is provided above the intake nozzles 14 and 15, and a pulley 19 fixed near the intake port of the intake nozzles 14 and 15 runs on the rail 18, so that an intake port portion is formed. A configuration is possible in which the bellows 26 can be moved along the rails 18 while expanding and contracting the bellows 26. The movement of the intake port is performed by a cylinder 23 fixed to the intake port.

A jack 24 is provided on the carry-in entrance 4 side of the suction nozzle 16. The bent portions of the shafts 25 and 26, which are erected on the jack and whose upper part is bent in an L-shape, are formed by the intake nozzle 16. The jack 24 is fixed to the intake port and moves up and down, so that the intake port moves up and down while expanding and contracting the bellows 26.

A device 30 for detecting the size of the article to be processed is provided in front of the loading port, which automatically detects the size of the article to be processed, and transmits this value to a central control device (not shown). The control device automatically moves the intake port to an appropriate position, and automatically rotates the partition plates 17a and 17b so that an appropriate gap is formed between the partition plates.

The coating film curing apparatus 1 of the present embodiment operates as follows.

The article to be processed 20 is conveyed from a coating chamber (not shown) by the conveyor 8 traveling in the direction of arrow A, the size of the article to be processed is detected by the detection device 30, and the suction port is positioned at an appropriate position. After moving and the partition plate rotating, it is carried into the curing chamber 2 from the carry-in entrance. In the curing chamber 2, the urethane-based coating film on the article to be treated 20 comes into contact with the amine or ammonia vapor supplied from the vapor generator 7 to the air supply unit 3 in the curing chamber by the air supply duct 9. To cure. After that, it exits the curing chamber 2 from the carry-out port 5 and is transported to a post-curing chamber (not shown).

At the carry-in or carry-out part, the intake nozzle determined by the position of the intake nozzle and the movement of air in the curing chamber by the intake nozzle moved to an appropriate position according to the size of the article to be processed. The air is constantly being taken. As a result, air in the curing chamber and outside the curing chamber is constantly sucked in at a constant volume. The air taken in here is passed through the intake duct, processed by the exhaust processing device 36, and then exhausted.

The air containing amine or ammonia vapor in the curing chamber passes through the exhaust duct 12 through the exhaust duct 11 and passes through the filter purifier 13.
, Where it is cleaned and then returned to the curing chamber 2 through an air supply duct, where it is repeatedly used. The supply amount of amine or ammonia into the curing chamber is automatically adjusted by the concentration control circuit 28 based on the value detected by the amine or ammonia concentration detector 27 provided in the curing chamber.

(Effect of the Invention) In the coating film curing apparatus of the present invention, articles to be processed having different shapes and sizes can be continuously processed. In addition, the opening area of the carry-in or carry-out port of the curing chamber can be changed at will according to the size of the article to be processed by the suction nozzle and the partition plate, so that leakage of amine or ammonia is more effectively prevented. be able to. In addition, since the intake air volume at the seal mechanism at the entrance or exit can be minimized, the consumption of amine or ammonia is reduced, and the burden on the device for filtering and cleaning the intake gas is reduced. However, the processing cost for the coating film curing treatment can be reduced.

[Brief description of the drawings]

FIG. 1 is a top view of a coating film curing apparatus according to one embodiment of the present invention, FIG. 2 is a view of a sealing mechanism of the coating film curing apparatus of FIG. 1 viewed from outside a curing chamber, and FIG. 3 is FIG. Top view of the seal mechanism of
FIG. 4 is a view of the seal mechanism of the conventional coating film curing apparatus as viewed from outside the curing chamber, FIG. 5 is a schematic view showing an air flow in the seal mechanism of FIG. 2, and FIG. 6 is a seal mechanism of FIG. It is a schematic diagram which shows the airflow in. DESCRIPTION OF SYMBOLS 1 ... Coating film hardening apparatus, 2 ... Hardening chamber 4 ... Carry-in port 5, ... Carry-out port 6 ... Seal mechanism, 14, 15, 16 ... Intake nozzles 17a, 17b ... Partition plate, 21 ... … Intake port 22 …… intake duct

Claims (1)

(57) [Claims] 1. A coating film curing apparatus for curing a coating film of a synthetic resin paint which forms urethane bonds in a coating film by curing in a curing chamber kept under an atmosphere of amine or ammonia. In the vicinity of the carry-in port and the carry-out port, an intake nozzle is provided for communicating with the intake duct and sucking the surrounding gas, and a part of the carry-in port and the carry-out port is located closer to the inside of the curing chamber than the intake nozzle. A partition plate for shielding the suction nozzle, the suction port of the suction nozzle is provided so as to be able to approach / separate from the workpiece to be cured with the coating film, and the suction port is provided to the workpiece. An apparatus for curing a coating film, comprising: an intake port moving mechanism that closes and separates a carry-in port and a carry-out port with a desired area by approaching and separating.