JPH0525743Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a coating drying oven in which entrances and exits for loading and unloading objects to be coated are opened at both ends of the oven body.

[Conventional technology]

A coating drying furnace that continuously dries objects to be coated is a tunnel-shaped furnace with openings at both ends of the furnace body through which objects to be coated are carried in and out.

There are generally two types of tunnel furnaces: flat furnaces and mountain furnaces.In flat furnaces, the hot air inside the furnace tends to leak out from the openings at both ends of the workpiece, resulting in large heat loss. A mountain-shaped furnace has both ends bent diagonally downward, and the entrance and exit for the workpiece is opened at a lower position than the furnace body, making it difficult for hot air to leak out and resulting in less heat loss than a flat furnace. It has less structure.

However, although mountain-shaped furnaces have less heat loss than flat-shaped furnaces, the hot air sealing performance that confines the hot air within the furnace body is still not sufficient, and compared to flat-shaped furnaces, both ends of the furnace have openings for entrance and exit. There was a problem that the length of the furnace became longer and the overall length of the furnace became larger.

For this reason, in addition to the flat type furnace and the angle type furnace, the furnace body 1 is formed into a flat type as shown in FIG. 4a and outlet 4b are opened on the lower surface of both ends of the furnace body 1, thereby shortening the overall length of the furnace and at the same time improving the hot air sealability.

This type of drying furnace uses hot air sucked from a suction duct 5 disposed at the upper part of the furnace body 1 at a working temperature (for example, in the case of paint baking drying, it is usually about 170°C to
180°C) and blows it out from the blow-off duct 6 disposed at the bottom of the furnace body 1 to spray the object to be coated 3.
At the same time, the exhaust gas containing harmful malodorous substances such as organic solvents, paint resins, and their curing agents evaporated from the paint film of the object to be coated 3 heated and dried in the furnace body 1 is passed through the inlet 4a and the outlet. In order to prevent leakage to the outside from the furnace body 1, the furnace body 1 is connected from above the inlet 4a and the outlet 4b at both ends of the furnace body
An exhaust port 9 of an exhaust duct 8 for sucking and discharging the exhaust gas therein by an exhaust fan 7 is opened.

[Problem that the invention attempts to solve]

However, a large amount of resin-like substances generated when substances contained in the exhaust gas are cooled adheres around the exhaust port 9, and the resin-like substances are coated on the workpiece 3 that is carried in and out from the inlet 4a and the outlet 4b. This had the disadvantage that it dripped onto the film and caused coating defects.

That is, high-temperature exhaust gas containing harmful malodorous substances evaporated from the coating film of the object to be coated 3 heated in the furnace body 1 passes from the inside of the furnace body 1 above the inlet 4a and the outlet 4b to the exhaust ports 9 and 4b, respectively. When the exhaust gas is sucked into the exhaust gas 9, it is cooled near the periphery of each exhaust port 9, and the evaporated substances in the exhaust gas are condensed, and a large amount of resin-like material is deposited and generated on the exhaust ports 9 and their surroundings.

In particular, in the furnace body 1 where electrodeposition coating is baked and dried, a large amount of smoky evaporated resin with a strong pungent odor is generated from coatings made of cationic and anionic paints. The amount of tar-like material deposited on and around the inlet 4a and the outlet 4b is also extremely large.

[Means for solving problems]

Therefore, the present invention provides a simple means to improve the entrance 4a.
It also prevents resin-like substances from being deposited above the outlet 4b, and prevents resin-like substances attached around the exhaust ports 9, 9 from forming on the coating film of the workpiece being carried in and out from the inlet 4a and outlet 4b. This was done to prevent the liquid from dripping into the water.

That is, in the present invention, an inlet and an outlet are opened at both ends of the furnace body for carrying in and out the object to be coated, and an exhaust port is opened above the inlet and outlet for sucking and discharging the exhaust gas in the furnace body. In the drying oven for painting, the inlet and the outlet are respectively formed on the lower surface of the oven body so as to be shifted toward the center of the oven body so as to be removed from directly below the exhaust port, and above the inlet and the outlet are respectively outer openings. A baffle plate is provided vertically between the end and the exhaust port to partition an upper space within the furnace body.

[Effect]

According to the present invention, since the inlet and outlet for loading and unloading the objects to be coated are opened on the lower surface of the furnace body, the hot air sealing properties are good and heat loss is extremely small.

In addition, the inlet and outlet are opened at a position shifted toward the center of the furnace body so as to be removed from directly below the exhaust port that sucks and discharges the exhaust gas inside the furnace body.
The tar-like substance dripping from the exhaust port does not drip onto the coating film of the workpiece being carried in and out from the inlet and outlet.

Furthermore, since baffle plates are installed vertically between the opening ends of the inlet and outlet and the exhaust port to partition the upper space inside the furnace body, the hot air inside the furnace body passes under the baffle plates and exits the exhaust port. is attracted to. Therefore, a pool of high-temperature hot air is always generated above the inlet and outlet adjacent to the exhaust port through the baffle plate, and evaporated substances in the exhaust gas condense above the inlet and outlet, causing resin-like substances to adhere. Since the generation is prevented, the tar-like substance attached around the exhaust port does not drip onto the coating film of the object to be coated, unlike in the conventional case.

〔Example〕

Hereinafter, embodiments of the present invention will be specifically described based on the drawings.

FIG. 1 is a sectional view showing an example of a coating drying oven according to the present invention. Incidentally, parts common to those in FIG. 2 already described are given the same reference numerals and detailed explanations are omitted.

In FIG. 1, the inlet 4a and outlet 4b for loading and unloading the workpiece 3 are located toward the center of the furnace body 1 so that they are out of the way directly below the exhaust ports 9, 9 that are opened at the top of both ends of the furnace body 1. It is opened at the lower surface of the furnace main body 1 in a staggered manner. That is, the lower surface of the furnace body 1 forms a blind portion directly below each of the exhaust ports 9 , 9 which are opened on the upper surface of the furnace body 1 . Drain pans 10 are provided at these blind locations to receive resin-like substances dripping from the exhaust ports 9, 9, respectively.

Further, baffle plates 11a and 11b are vertically installed above the inlet 4a and the outlet 4b, respectively, to partition the upper space within the furnace body 1 between the opening ends of the inlet 4a and the outlet 4b. That is, the space above the inlet 4a and the outlet 4b and the space on the side of each exhaust port 9 are partitioned by the baffle plates 11a and 11b, respectively, so that the hot air inside the furnace body 1 is directed to the inlet 4.
a and the outlet 4b from above, passing between the lower end of each baffle plate 11a and 11b and the drain pan 10, and being sucked into the exhaust ports 9, 9.

According to such a configuration, the inlet 4a and outlet 4b for carrying in and out the workpiece 3 are connected to the furnace main body 1.
Since the opening is on the bottom surface, the hot air sealing property is very good, there is little heat loss, and energy saving is achieved. Since the opening is shifted toward the center of the exhaust port 1, the resin-like material that adheres to the exhaust ports 9 and drips down will be removed from the inlet 4.
This prevents dripping onto the coating film of the object to be coated 3 carried in and out from the outlet 4b and the outlet 4b.

Further, baffle plates 11a and 11b are vertically installed between the opening ends of the inlet 4a and the outlet 4b and each exhaust port 9 to partition the upper space in the furnace body 1, and the hot air inside the furnace body 1 is directed to the baffle plates. Since the structure is such that the air is sucked and discharged from the exhaust ports 9, 9 through the lower ends of 11a, 11b, the air is always above the inlet 4a and outlet 4b adjacent to each exhaust port 9 via the baffle plates 11a, 11b. A high temperature hot air pool H is formed.

With this, when the exhaust gas in the furnace body 1 is sucked into each exhaust port 9, 9 from above the inlet 4a and outlet 4b close to the exhaust ports 9, 9, the exhaust gas is Since the temperature does not drop, the condensation of evaporated substances contained in the exhaust gas is prevented, and the formation of tar-like substances on the inner wall of the furnace body 1 above the inlet 4a and outlet 4b is prevented. Prevented.

Therefore, unlike in the past, there is no risk of resin-like substances dripping from the exhaust ports 9 and their surroundings and dripping onto the paint film of the workpiece being carried in and out from the inlet 4a and outlet 4b, thereby reducing paint film defects. occurrence is reliably prevented.

Note that the exhaust ports 9, 9 are not limited to opening at the upper surface of the furnace body 1, but may be opened at the upper part of the front end surface or the rear end surface of the furnace body 1.

[Effect of idea]

As described above, according to the present invention, with an extremely simple configuration, paint film defects caused by dripping of tar-like substances on the paint film of the workpiece carried in and out from the entrance opened on the bottom surface of the furnace main body can be avoided. It has the excellent effect of reliably preventing the occurrence of.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a coating drying oven according to the present invention, and FIG. 2 is a sectional view showing a conventional coating drying oven. Explanation of symbols, 1...furnace body, 4a...inlet, 4
b...Exit, 9...Exhaust port, 11a, 11b...
baffle board.

Claims (1)

[Scope of utility model registration request] An inlet 4a and an outlet 4b for carrying in and out the workpiece 3 are opened at both ends of the furnace body 1, and exhaust ports 9, 9 for sucking and discharging exhaust gas in the furnace body 1 are provided above the inlet 4a and outlet 4b. In a drying furnace for painting having an opening, the inlet 4a and the outlet 4b are formed on the lower surface of the furnace body 1 so as to be shifted toward the center of the furnace body 1 so as to be removed from directly below the exhaust ports 9, 9, respectively. Above the inlet 4a and the outlet 4b are baffle plates 11a and 1 that partition the upper space in the furnace body 1 between the outer open ends of the inlets 4a and the exhaust ports 9, 9, respectively.
1b is installed vertically.