JP2021151631A - Roll coater type applicatioin device - Google Patents

Abstract

To provide a roll coater type application device capable of stably applicating paint over a long period and manufacturing a belt-like body having good application of paint thereon.SOLUTION: A soaking pan 15 is provided under a doctor roll 12 having an applicator roll 11 for applying paint to a belt-like body 1 and a doctor roll 12 for transferring supplied paint to the applicator roll 11, and a part of the doctor roll 12 is soaked in the paint in the soaking pan 15. Accordingly, even if there is insufficiency in the paint supplied to the doctor roll 12, it can be supplemented. Thus, the doctor roll 12 and the applicator roll 11 are made more difficult to be worn, so that the belt-like body 1 with high paint uniformity can be stably manufactured over a long period, as a result of which productivity is also improved.SELECTED DRAWING: Figure 1A

Description

The present invention relates to a roll coater type coating device used for coating a strip-shaped body such as a steel strip.

As a method of applying the paint to the surface of the strip such as a steel strip, the paint is supplied to the roll surface and the paint is applied to the surface of the strip through the paint. There are mainly two methods for painting using such a roll.
As a first coating method, paint is supplied between a plurality of rotating cylindrical rolls, and a gap between one roll (called a doctor roll or the like) and another roll (generally called an applicator roll or the like) is formed. This is a method in which the amount of the paint to be adjusted and transferred to the applicator roll is kept constant, and the paint is applied to the strip (see, for example, Patent Document 1 and Patent Document 2).
The second coating method is to immerse the lower part of one roll (generally called a pickup roll or the like) in the paint, and then directly or indirectly apply the paint scooped up by the pickup roll to the strip. (See, for example, Patent Documents 3 to 5).

While the second coating method is simple, since it is necessary to fill the paint pan with a large amount of paint, partial paint stagnation occurs when the paint is circulated, and the paint solidifies, deposits accumulate, and circulates. Pipe clogging or paint overflow is likely to occur. Therefore, the first coating method in which these phenomena are unlikely to occur is preferred.

Japanese Unexamined Patent Publication No. 2004-209441 Japanese Unexamined Patent Publication No. 2005-74366 Japanese Unexamined Patent Publication No. 2000-126660 Japanese Unexamined Patent Publication No. 10-337522 Japanese Unexamined Patent Publication No. 2010-149070

However, when the first coating method is performed, it is difficult to uniformly adjust the pressure in the width direction between the rolls and the amount of the supplied paint in the width direction. Poor uniformity. Further, when the roughness is lowered due to the wear of the rolls or the clogging of the chemical solution, it becomes difficult to adjust the gap between the rolls, and it is difficult to stably produce a strip-shaped body having a good coating state.

Therefore, the inventors have investigated the problem that the coated state cannot be stably maintained when the roll is worn.
That is, when considering the uniform application of the paint to the strip, it is premised that the first application method, that is, the method of supplying the paint between the two rotating cylindrical rolls.
However, roll wear is unavoidable manufacturingally. When the rolls are worn, it is necessary to adjust the roll spacing with screws, but in the first application method, there are usually three rolls (applicator roll, doctor roll, and dam roll that actually apply paint to the strip). ) Is used, and it is necessary to determine the wear state of the three rolls and adjust each of them, which is difficult to adjust. Therefore, it is advantageous to add another method to more easily adjust the coating state.

Therefore, the present inventors thought that the doctor roll should be wetted as an auxiliary. Specifically, the pan may be placed under the doctor roll, and the paint may be collected therein to wet the doctor roll. This method is different from the above-mentioned second coating method in which the pick-up roll is immersed in the paint and then the paint scooped up by the pick-up roll is directly or indirectly applied to the strip. The doctor roll is dipped in order to make up for the insufficient amount of paint by performing the coating method.

Therefore, it is not necessary to prepare a large pan and supply a large amount of paint to the pan as in the second coating method, and even a relatively small pan about the size of a doctor roll. All you need is. If there is a large pan for receiving dripping, a small pan may be prepared on it. However, when a small pan is used, the fluidity of the paint tends to deteriorate, so that the paint may not be sufficiently circulated and the paint may solidify. Therefore, it is preferable that the paint can be circulated.

As for the circulatory device, various types of circulatory devices are considered. For example, the invention described in Patent Document 3 discloses a circulation device in which a paint discharge port and a suction port are arranged so that the paint flows perpendicularly to the width direction of the roll (circumferential direction of the roll). When the second coating method is adopted in this way, it is common to flow the paint in the circumferential direction of the roll in order to prevent the paint unevenness from occurring on the left and right in the width direction of the roll.
Further, also in the invention described in Patent Document 4 and the invention described in Patent Document 5, the paint is allowed to flow in the circumferential direction of the roll. In this case, the paint may solidify as described above.
In particular, if the first coating method is used to immerse the paint to make up for the insufficient amount of paint, the paint flows in the direction perpendicular to the rotation direction (circumferential direction) of the doctor roll (roll width direction). It was considered advantageous to make the paint more agitated and to make the paint harder to cure.

The present invention has been made based on the above-mentioned studies, and provides a roll coater type coating apparatus capable of stably applying a coating material for a long period of time and producing a strip-shaped body in which the coating material is applied in a good state. With the goal.

In order to achieve the above object, the roll coater type coating apparatus of the present invention is a roll coater including an applicator roll for applying paint to a strip and a doctor roll for transferring the supplied paint to the applicator roll. It ’s a type painting device,
An immersion pan is provided below the doctor roll.
A part of the doctor roll is immersed in the paint in the immersion pan.

Here, in order to supply paint to the doctor roll, for example, a dam roll rotating in the opposite direction to the doctor roll is arranged so as to be in contact with the doctor roll or arranged with a predetermined gap between the doctor roll and the dam roll. The paint may be supplied from above.
Further, in order to apply the paint to the strip by the applicator roll, for example, a backup roll rotating in the same direction as the applicator roll is arranged so as to be in contact with the applicator roll or arranged with a predetermined gap to back up. By wrapping the strip around the roll, the paint may be applied by pressing the applicator roll against the strip that rotates with the backup roll while supporting and advancing (rotating) the strip.
Further, the shape and size of the dipping pan are not limited as long as the doctor roll can be dipped in the paint.
However, the dipping pan preferably has a semi-cylindrical shape that matches the shape of the doctor roll. In other words, it is preferably slightly larger than the size of the doctor roll and has a semi-cylindrical shape. In this way, only the required amount of paint needs to be stored in the dipping pan, so that the cost advantage can be enjoyed.

In the present invention, when the paint supplied to the doctor roll is transferred to the applicator roll and the paint is applied to the strip by the applicator roll, a part of the doctor roll is immersed in the paint in the dipping pan. This makes it possible to make up for a shortage of paint supplied to the doctor roll.
Therefore, the doctor roll and the applicator roll are less likely to be worn, and even if they are worn, the rolls (doctor roll and applicator roll) do not need to be finely adjusted (screw adjustment, etc.) for a long time. It becomes possible to stably produce a strip-shaped body having high coating uniformity, and as a result, productivity is also improved.

Further, in the above-mentioned configuration of the present invention, in the dipping pan, the paint may be supplied from one end side in the width direction of the doctor roll and discharged from the other end side in the width direction of the doctor roll.

Here, in the dipping pan, the paint flows from one end side to the other end side in the width direction of the doctor roll, but the flow of the paint may be forcibly created by a propeller device or the like. However, for convenience, the dipping pan may be tilted so that the paint flows due to gravity.

According to such a configuration, the flow of the paint in the dipping pan can be in the axial direction (width direction) of the doctor roll, and the flow of the paint is orthogonal to the rotating doctor roll (rotation in the circumferential direction). , The paint is sufficiently agitated, and solidification of the paint can be prevented.

Further, in the above-mentioned configuration of the present invention, a saucer larger than the dipping pan is provided below the dipping pan.
The paint discharged from the other end side of the dipping pan may be temporarily stored in the saucer and sequentially circulated in the dipping pan.

Here, the paint is circulated for a long time so that the paint is discharged to the outside of the immersion pan from the other end side in the width direction of the doctor roll and the paint is directly supplied to the immersion pan from the one end side in the width direction of the doctor roll. If this is done, sludge (precipitate) tends to accumulate in the dipping pan.
The smaller the size of the dipping pan, in other words, the smaller the size of the dipping pan, and the smaller the amount of paint used when the shape is a semi-cylindrical body. In such a case, if sludge is generated in the paint, sludge is likely to adhere to the doctor roll, and the properties of the coating film are likely to be deteriorated.
Therefore, the paint discharged from the other end side of the dipping pan is temporarily stored in the pan and is sequentially circulated in the pan, so that the sludge can be easily captured by the pan and the sludge can be easily removed.

According to the present invention, it is possible to stably apply the paint for a long period of time and to produce a strip-shaped body in which the paint is applied in a good state.

It is a side view which shows typically the schematic structure of the roll coater type coating apparatus which concerns on this embodiment. FIG. 5 is a side view schematically showing a schematic configuration when a second dam roll is added to the roll coater type coating apparatus shown in FIG. 1A. It is a side view which shows typically the schematic structure when the adjustment roll is added to the roll coater type coating apparatus shown in FIG. 1B. It is a perspective view which shows typically the schematic structure of the immersion pan of the roll coater type coating apparatus which concerns on this embodiment. It is a perspective view which shows typically the schematic structure of another example of the dipping pan of the roll coater type coating apparatus which concerns on this embodiment. The dipping pan and the doctor roll of the roll coater type coating apparatus according to the present embodiment are shown, where (a) is a plan view and (b) is a sectional view taken along line AA in (a).

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1A is a side view schematically showing a schematic configuration of a roll coater type coating apparatus according to the present embodiment.
This roll coater type coating device includes a backup roll 10, an applicator roll 11, a doctor roll 12, and a dam roll 13.
Further, a dipping pan 15 is provided below the doctor roll 12, and a part (lower portion) of the doctor roll 12 is immersed in the paint in the dipping pan 15.

The backup roll 10 plays a role of supporting the strip 1 such as a steel strip and advancing (rotating) the strip 1. That is, by winding the strip-shaped body 1 around the backup roll 10, the strip-shaped body 1 is supported and the backup roll 10 is rotated to advance (rotateally move).

The applicator roll 11 plays a role of applying the paint to the strip-shaped body 1, and is in contact with the backup roll 10 or has a predetermined gap (a gap corresponding to the thickness of the strip-shaped body 1) with respect to the backup roll 10. Have been placed. Then, the paint is applied by pressing the applicator roll 11 while rotating it against the band-shaped body 1 that rotates and moves by the rotation of the backup roll 10. As such an applicator roll 11, a cylindrical or columnar metal roll having a rubber coating on its surface can be used.

The doctor roll 12 plays a role of adhering the paint P supplied to the doctor roll 12 and the paint stored in the dipping pan 15 and transferring the adhered paint to the applicator roll 11. It is in contact with the taror 11 or is arranged with a predetermined gap.

Further, the dam roll 13 is arranged in contact with the doctor roll 12 or with a predetermined gap, and the paint P is supplied to the doctor roll 12 by supplying the paint P between the dam roll 13 and the doctor roll 12 from above. It has become so. Further, the doctor roll 12 can adjust the amount of paint to be transferred to the applicator roll 11 by adjusting the pressure and the relative speed (rotational speed) with the applicator roll 11. The doctor roll 12 is made of a metal roll.
Although paint is supplied to the doctor roll 12 at any time, a part of the paint in the saucer 18, which will be described later, may be supplied.
The dam roll 13 plays a role of adjusting the amount of the paint P supplied between the doctor roll 12 and the dam roll 13, and is composed of a metal roll.

The roll coater type coating apparatus of the present embodiment includes four rolls of a backup roll 10, an applicator roll 11, a doctor roll 12, and a dam roll 13, but as shown in FIG. 1B, a second dam roll 23 is further provided. May be provided.
The second dam roll 23 plays a role of removing the paint adhering to the dam roll 13 and adjusting the surface texture of the dam roll 13, and is in contact with the dam roll 13 or is arranged with a predetermined gap.
As such a second dam roll 23, one in which urethane is wound on the surface of a cylindrical or columnar metal roll can be used.

Further, the more the paint is applied to the strip 1 via many rolls, the easier it is to adjust the film thickness of the paint. Therefore, as shown in FIG. 1C, between the applicator roll 11 and the doctor roll 12. The adjusting roll 24 may be provided.

Further, as shown in FIGS. 1A to 1C, a dipping pan 15 is provided below the doctor roll 12. A part (lower part) of the doctor roll is immersed in the paint in the immersion pan 15.
In the present embodiment, the paint P is supplied from above between the doctor roll 12 and the dam roll 13, but the paint application becomes difficult due to the wear of the rolls (applicator roll 11, doctor roll 12 and dam roll 13). Even if there is a shortage in the paint P supplied from above by the paint from the dipping pan 15, the paint can be stably applied by compensating for the shortage.

The shape and size of the dipping pan 15 does not matter as long as a part (lower part) of the doctor roll 12 can be dipped in the paint. However, the immersion pan 15 preferably has a semi-cylindrical shape that matches the shape of the doctor roll 12. In other words, it is preferable that the size is slightly larger than the size of the doctor roll 12 and the shape is a semi-cylindrical body. In this way, it is only necessary to store the required amount of paint in the dipping pan 15, so that a cost advantage can be enjoyed.

As shown in FIGS. 2A and 3, the dipping pan 15 is formed in a semi-cylindrical shape obtained by halving a hollow cylindrical body along the axial direction, and the paint is applied from one end portion 15a in the axial direction. It is supplied and discharged from the other end 15b side.
A substantially rectangular discharge port 15c is formed on the end surface of the immersion pan 15 on the other end 15b side, and the paint is discharged from the discharge port 15c.
Further, as shown in FIG. 2B, the paint is discharged from the upper end edge of the end face wall 15d by forming the height of the end face wall 15d on the other end 15b side of the immersion pan 15 lower than the end face wall on the one end 15a side. You may let it.

By supplying the paint to the immersion pan 15 from the one end portion 15a side and discharging the paint from the other end portion 15b side in this way, the flow of the paint can be made in the axial direction (width direction) of the doctor roll 12. As a result, the flow of the paint is orthogonal to the rotating doctor roll 12 (rotating in the circumferential direction), so that the paint is sufficiently agitated and solidification of the paint can be prevented.
The flow of the paint may be forcibly created by a propeller device or the like, but for convenience, the dipping pan 15 may be inclined so that the paint flows by gravity. In this case, the immersion pan 15 may be arranged so as to be inclined with respect to the horizontal plane so that the one end portion 15a of the immersion pan 15 is located above the other end portion 15b.

Further, as shown in FIG. 3, the other end portion 15a of the immersion pan 15 and the other end portion 12b of the doctor roll 12 are separated from each other by the distance between the one end portion 15a of the immersion pan 15 and the one end portion 12a of the doctor roll 12. The distance between them is getting longer. In other words, the doctor roll 12 is arranged inside the dipping pan 15 so as to be closer to the other end portion 15b side, whereby the one end portion 12a of the doctor roll 12 and the one end portion 15a of the dipping pan 15 are separated from each other. It's getting wider. Then, the paint is supplied to the dipping pan 15 from this widened portion.

Further, as shown in FIG. 1, a saucer 18 larger than the immersion pan 15 is provided below the immersion pan 15. The saucer 18 is a roll other than the backup roll 10 (applicator roll 11, doctor roll 12 and dam roll 13 in FIG. 1A, applicator roll 11, doctor roll 12, dam roll 13 and second dam roll in FIG. 1B. 23. In FIG. 1C, the applicator roll 11, the adjusting roll 24, the doctor roll 12, the dam roll 13 and the second dam roll 23) are arranged below these rolls so as to be arranged inside the plan view.
Therefore, the paint discharged from the dipping pan 15 and the paint dripping from the applicator roll 11, the dam roll 13, the second dam roll 23 and the adjusting roll 24 are collected in the saucer 18, and the paint is temporarily collected. It is designed to be accumulated in the water and sequentially passed through the circulation path 25 to be circulated to the immersion pan 15.

A paint circulation device may be installed so that the paint is discharged from the other end 15b side of the dipping pan 15 to the outside of the dipping pan 15 and directly supplied from the one end side. In this case, the paint is circulated for a long time. Then, sludge (sediment) accumulates in the immersion pan 15.
Further, when the size of the dipping pan 15 is small, in other words, the size of the dipping pan 15 is slightly larger than the size of the doctor roll 12 and the shape is a semi-cylindrical body, the amount of paint to be used is also large. Less. In such a case, if sludge is generated in the paint, the sludge is likely to adhere to the doctor roll 12, and the properties of the coating film are likely to be deteriorated. Therefore, if the paint discharged from the dipping pan 15 is temporarily stored in the large pan 18 arranged below the dipping pan 15 and sequentially circulated, the sludge can be easily captured by the pan 18 and the sludge can be easily removed. become able to.

As described above, according to the present embodiment, when the paint P supplied to the doctor roll 12 is transferred to the applicator roll 11 and the paint is applied to the strip 1 by the applicator roll 11, the dipping pan 15 is used. By immersing a part (lower part) of the doctor roll 12 in the paint inside, even if the paint supplied to the doctor roll 12 is insufficient, it can be compensated for.
Therefore, the doctor roll 12 and the applicator roll 11 are less likely to be worn, and even if they are worn, the rolls (doctor roll 12 and applicator roll 11) do not need to be finely adjusted (screw adjustment, etc.) each time. However, it becomes possible to stably produce the strip-shaped body 1 having high coating uniformity for a long period of time, and as a result, the productivity is also improved.

Further, in the dipping pan 15, the paint is supplied from one end (one end in the axial direction of the doctor roll 12) 15a side and discharged from the other end 15b side, so that the flow of the paint in the dipping pan 15 is drawn by the doctor. Since the roll 12 can be in the axial direction (width direction) and the flow of the paint is orthogonal to the rotating doctor roll 12 (rotating in the circumferential direction), the paint can be sufficiently agitated to prevent the paint from solidifying. can.
Further, a saucer 18 larger than the immersion pan 15 is provided below the immersion pan 15, and the paint discharged from the other end 15b side of the immersion pan 15 is temporarily stored in the saucer 18 and sequentially stored in the immersion pan 15. Since it is circulated, sludge can be easily removed by capturing sludge with a saucer.

(Example)
For a roll coater type coating apparatus having a backup roll 10, an applicator roll 11, a doctor roll 12, and a dam roll 13 and a saucer 18 below the applicator roll 11, the doctor roll 12, and the dam roll 13 for receiving paint dripping. A dipping pan 15 for storing the paint was newly placed directly under the doctor roll 12.

The paint is supplied between the doctor roll 12 and the dam roll 13, the paint is introduced into the doctor roll 12, the paint is transferred to the applicator roll 11 via the doctor roll 12, and the paint is applied to the strip (steel strip) 1. Was applied.
At this time, the immersion pan 15 is filled with sufficient paint so that the doctor roll 12 can be immersed, and the paint is supplied from one end in the width direction of the doctor roll 12 and discharged from the other end, so that the paint can constantly flow and circulate. I did.
Specifically, the immersion pan 15 is provided with an inclination that inclines up and down in the axial direction of the doctor roll 12, and the immersion pan 15 is provided with a structure that allows the paint to flow and circulate due to the inclination. Further, the paint discharged to the outside of the dipping pan 15 was temporarily received by the conventionally existing saucer 18, regenerated so that it could be supplied to the dipping pan 15 again, and then the paint was circulated.

Conventionally, if paint is missing (part of the paint cannot be applied and the non-applied part can be made into a steel strip) or uneven paint occurs by the time of regular repair, if there is a sign that it will occur, fine-tune the roll and re-steel. Whereas the paint was applied to the band, by arranging the dipping pan 15 and circulating the paint as described above, paint omission and paint unevenness occur without making fine adjustments to the roll until regular repairs are performed. It was possible to apply paint to the steel strip.

1 strip 10 backup roll 11 applicator roll 12 doctor roll 13 dam roll 15 immersion pan 15a one end 15b other end 18 saucer

Claims (3)

A roll coater type coating device including an applicator roll for applying paint to a strip and a doctor roll for transferring the supplied paint to the applicator roll.
An immersion pan is provided below the doctor roll.
A roll coater type coating apparatus, characterized in that a part of the doctor roll is immersed in the paint in the immersion pan. The roll coater type coating apparatus according to claim 1, wherein in the dipping pan, paint is supplied from one end in the width direction of the doctor roll and discharged from the other end in the width direction of the doctor roll. .. Below the dipping pan, a saucer larger than the dipping pan is provided.
The roll coater type coating apparatus according to claim 2, wherein the paint discharged from the other end of the dipping pan is temporarily stored in the saucer and sequentially circulated in the dipping pan.

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