JPH0710369B2 - Dryer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a drying device in which an entrance for loading and unloading an object to be coated is formed on the lower surface side of a drying furnace.

[Conventional technology]

A normal drying apparatus generally uses a tunnel furnace in which inlets and outlets for loading and unloading the object to be coated have openings formed on both left and right sides of the drying furnace. There is a drawback that hot air easily leaks from the entrance and the heat loss is large.

In order to reduce this heat loss, there is also a drying device in which the inlets / outlets 2a and 2b of the article to be coated W are opened on the lower surface side of the drying furnace to enhance the hot air sealing property, as shown in FIG.

This type of drying device heats the hot air sucked from the suction duct 3 provided along the upper part of the drying furnace 1 to a use temperature (usually about 170 ° C to 180 ° C when baking drying is performed), This is blown out from a blowing duct 4 arranged in the lower part of the drying furnace 1 to heat and dry the coating film of the article W to be coated. Further, it is possible to prevent the exhaust gas containing harmful malodorous substances such as an organic solvent, a coating resin or a curing agent for the same, which has evaporated from the coating film of the article W to be heated and dried in the drying furnace 1 from leaking out from the entrances 2a and 2b. In order to do so, exhaust ports 7 of exhaust ducts 6 for sucking and discharging the exhaust gas in the drying furnace 1 by the exhaust fan 5 are opened at the left and right ends of the drying furnace 1 from above the inlets / outlets 2a, 2b, respectively.

[Problems to be Solved by the Invention]

However, around the exhaust port 7, a large amount of the tar-like substance produced by cooling the harmful foul-smelling substance contained in the exhaust gas adheres, and the tar-like substance of the coating object W that is carried in and out through the inlets and outlets 2a and 2b. There was an adverse effect that it was dropped on the coating film to cause a defective coating film.

That is, the high-temperature exhaust gas containing a large amount of harmful odorous substances that evaporate from the coating film of the article W heated in the drying furnace 1
In the vicinity of the exhaust ports 7 and 7 mixed with the outside air sucked into the drying furnace 1 from the inlets 2a and 2b when being sucked into the exhaust ports 7 and 7 passing above the inlets and outlets 2a and 2b of the drying furnace 1. When cooled, the evaporation material in the exhaust gas is condensed and a large amount of tar-like material is attached and generated at the exhaust ports 7, 7 and its surroundings.

In particular, in the drying furnace 1 for baking and drying the electrodeposition coating, a large amount of smoke-like vaporized tar-like substances with a strong irritating odor is generated from the coating film made of cationic paint or anionic paint, so the entrance / exit 2a At the same time, the amount of tar-like substance dripping from the upper part of 2 and 2b was remarkably increased, and at the same time, smoke having a strong stimulating odor leaking from the entrances and exits 2a and 2b had a bad effect on the external environment.

Therefore, the present invention significantly reduces the amount of exhaust gas leaking from the inlet / outlet opening formed on the lower surface side of the drying furnace and the amount of the tar-like substance adhered and generated above the inlet / outlet, and the generated tar. It is a technical issue to prevent the particulate matter from dripping on the article to be loaded and unloaded from the entrance and exit, and by solving this issue, the coating film defect of the article to be coated and the adverse effects of environmental deterioration are surely prevented. The purpose is to

[Means for Solving the Problems]

In order to achieve this object, the present invention, in a drying device having an inlet / outlet for loading and unloading an object to be coated formed in an opening on the lower surface side of a drying furnace, an elevating platform for loading or unloading the object to be loaded into or out of the drying furnace. However, while being installed below the doorway, the elevator is provided with a ceiling plate that is arranged above the object to be coated placed on the elevator and faces the elevator so as to overlap with the elevator. When the elevator is raised, the entrance is closed by the elevator, and when the elevator is lowered, the entrance is closed by the ceiling plate provided on the elevator. Characterize.

[Action]

According to the present invention, the entrance / exit of the drying oven is blocked by the ceiling plate provided on the lifting table when the lifting table is lowered.

In this state, the article to be coated is placed on the elevating table, the elevating table is raised, and the article to be coated is carried into the drying oven.

Here, for example, in the case where the article to be coated carried into the drying oven is heated and dried while being placed on the elevator, the entrance of the drying oven is blocked by the elevator until the heating and drying is completed.

Then, when the heating and drying is completed, the elevating table is lowered, the article to be coated placed on the elevating table is carried out from the inlet / outlet of the drying oven, and the inlet / outlet from which the object is delivered is the ceiling plate of the elevator table. Is blocked by.

As a result, the amount of hot air leaking from the inside of the drying furnace to the outside through the inlet and outlet is significantly reduced, and at the same time, the amount of outside air entering the inside of the drying oven through the inlet and outlet is also significantly reduced.

Therefore, the hot air sealability of the drying oven is improved and heat loss is reduced, at the same time the deterioration of the external environment due to hot air leakage is prevented, and the amount of tar-like substances deposited and formed above the inlet and outlet in the drying oven is also greatly reduced. To do. Further, since the tar-like substance that drips from above the doorway is received by the ceiling plate provided on the elevator, a coating film defect may occur due to the adhesion of the tar on the surface of the object to be coated placed on the elevator. Disappear.

In the case of transferring the object to be coated carried into the drying oven from the lift to the conveyor provided in the drying furnace and heating and drying while conveying in the drying furnace, the loading of the object to be coated was completed. Immediately lower the elevating table, place the article to be carried in next, and raise it again. Also in this case, since the inlet and outlet of the drying oven are alternately blocked by the lifting platform and its ceiling plate when carrying in the object to be coated, the amount of hot air leaking outside the drying oven is reduced and at the same time the inside of the drying oven is reduced. The amount of outside air entering the
As a matter of course, a coating film defect due to the adhesion of a varnish does not occur on an object to be coated which is loaded on an elevator.

〔Example〕

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a front view of a main part showing an example of a drying device according to the present invention.

The same parts as those in FIG. 2 are designated by the same reference numerals and detailed description thereof will be omitted.

In the drying apparatus shown in this example, as in the case of FIG. 2, two inlets / outlets 2a and 2b are formed on the lower surface side of the drying oven 1, one of which serves as a carry-in inlet 2a for the article W and the other of It serves as an outlet 2b for the coating material W.

Below the carry-in port 2a, an elevator 8 for mounting the article W to be coated is installed, and when the platform 8 rises, the elevator 8 carries the carry-in port.
When the 2a is closed and descends, the carry-in port 2a is closed by the ceiling plate 9 provided on the elevator 8.

The lift table 8 is driven up and down while maintaining a horizontal state by a lifter 10 installed on the side of the lift table 8.
A conveyer 13 is installed which receives the article W transferred from the carry-in conveyor 11 arranged downwardly and transfers it to the conveyer 12 arranged in the drying furnace 1.

The ceiling plate 9 is horizontally attached to the upper ends of columns 14 standing upright at one corner of the lifting table 8 and is placed on the lifting table 8 to be coated W.
Is arranged above and faces the lift table 8.

Also, below the carry-out port 2b, an elevating table 8 on which the article W to be coated is placed
Is installed, and the conveyor 13 placed on the elevator 8 is
The coating object W transferred by the conveyor 12 in the drying furnace 1 is received and delivered to the carry-out conveyor 15 arranged below the carry-out port 2b.

Then, when the lift 8 installed below the carry-in entrance 2a is descending, the carry-in entrance 2a is closed by the ceiling plate 9 provided on the lift 8 and the carry-in conveyor 11 in this state. The article to be coated W sent from is received by the conveyor 13 and placed on the lift 8.

Then, the lifter 10 is activated to raise the lifting table 8, and the article W placed on the lifting table 8 is carried into the drying furnace 1.

At this time, the carry-in port 2a is closed by the lift 8 instead of the ceiling plate 9, and the conveyor 13 is driven in this state to move the object W to be coated on the lift 8 in the drying furnace 1. Hand it over to the conveyor 12.

When this transfer is completed, the lifter 8 is lowered by the lifter 10, the ceiling plate 9 provided on the lifter 8 closes the carry-in port 2a again, and the article to be subsequently carried into the lowered lifter 8 is coated. Place W.

On the other hand, the lifting platform 8 installed below the carry-out port 2b stands by while being lifted by the lifter 10 to block the carry-out port 2b, and the coated object W sent from the conveyor 12 in the drying oven 1 When it is received by the conveyor 13, the lifter 10 is activated and descends.

At this time, the carry-out port 2b is closed by the ceiling plate 9 instead of the lift table 8, and in this state, the conveyor 13 is driven to transfer the article W on the lift table 8 to the carry-out conveyor 15. .

When this delivery is completed, the lifter 10 raises the lift 8 again, and the lift 8 closes the carry-out port 2b and waits until the next object W to be coated arrives.

In this way, if the carry-in port 2a and the carry-out port 2b are alternately closed by the respective elevators 8 and their ceiling plates 9, the drying furnace 1 is exposed to the outside through the carry-in port 2a and the carry-out port 2b of the article W to be coated. The amount of hot air that leaks into the drying oven and the amount of cold outside air that enters the drying oven 1 are greatly reduced, the hot air sealability of the drying oven 1 is significantly improved, and heat loss is reduced. Deterioration is prevented, and the amount of tar-like substances adhered and generated above the carry-in port 2a and the carry-out port 2b is significantly reduced.

Further, since the tar-like substance dripping from above the carry-in entrance 2a and the carry-out exit 2b is received by the ceiling plate 9 provided on the elevator 8, the surface of the article W placed on the elevator 8 is covered with tar-like substances. The substance does not drip, and the defective coating film of the article W is reliably prevented.

〔The invention's effect〕

As described above, according to the present invention, the hot air sealing property of the drying furnace is significantly improved, and the hot air leakage from the inlet / outlet is significantly reduced. It has an excellent effect of preventing the exhaust gas containing the strong smoke-like harmful odorous substance from leaking out of the drying furnace and damaging the external environment.

In addition, since the amount of outside air that enters from the inlet / outlet of the drying furnace is also greatly reduced, not only the heat loss in the drying furnace is reduced, but also the amount of tar-like substances attached and generated above the inlet / outlet is significantly reduced. Decrease. Moreover, there is a very excellent effect that the tar-like substance dripping from above the entrance does not drop on the object to be coated passing through the entrance to cause a defective coating film.

[Brief description of drawings]

FIG. 1 is a front view of a main part showing an example of a drying device according to the present invention, and FIG. 2 is a front view of a conventional device. Explanation of symbols W: coating object, 1 ... drying oven, 2a ... entrance / exit (carrying object entrance), 2b ... entrance / exit (painting object exit), 8 ... elevator, 9 ... … Ceiling board, 10 …… lifter.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sho Kaho Takashi Toyota-cho, Toyota City, Aichi Prefecture Toyota Motor Co., Ltd. (72) Shunichi Akiyama 1-cho, Toyota City, Aichi Prefecture Toyota Motor Co., Ltd. (72) Inventor Haruo Murase 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Co., Ltd.

Claims (1)

[Claims] 1. A doorway (2a, 2) for loading and unloading an article (W) to be coated.
In the drying device in which b) has an opening formed on the lower surface side of the drying oven (1), the lift (8) for loading or unloading the article to be coated (W) into or out of the drying oven (1) is the entrance (2a). , 2b), and a ceiling which is arranged above the object (W) placed on the elevator (8) and faces the elevator (8) so as to overlap with the elevator. A plate (9) is provided, and when the elevator (8) rises, the elevator closes the entrances (2a, 2b), and when the elevator (8) descends, the elevator (8). A drying device, characterized in that the entrance (2a, 2b) is closed by the ceiling plate (9) provided in the.