JP2588349Y2 - Roll coater type coating equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roll coater type coating apparatus for applying a paint or a resin to the front and back surfaces of a continuously running steel strip.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for coated steel sheets excellent in rust prevention, lubrication, decoration, etc. for use in construction or home electric appliances, and a roll coater type coating apparatus is generally used for continuous coating of steel sheets. It is used for

The above-mentioned roll coater type coating apparatus has been proposed, for example, in Japanese Patent Publication No. Sho 60-56552.
As shown in FIG. 2, this coating apparatus has a paint pan 9 at the lower part.
An applicator roll 3 disposed close to the pickup roll 2 immersed in the paint therein with a required gap is configured so as to be in contact with, for example, a steel strip S wound around the backup roll 1. Pickup paint from paint pan 9 adhered to roll 2
Is applied to the steel strip S wound around the backup roll 1 via the applicator roll 3 rotating at a constant speed ratio. In this coating equipment,
By changing the pressing pressure and the rotation speed ratio between the pickup roll 2 and the applicator roll 3, the steel strip S
Adjust the thickness of the paint to be adhered to.

Further, the latest coating technology (enhanced version)
FIG. 3 shows a coating apparatus disclosed on page 347 (supervised by Yuji Harazaki General Technology Center). This coating apparatus includes a backup roll 1 and a dual-purpose roll 8 that functions as a pickup roll and an applicator roll.
A doctor roll 5 for adjusting the thickness of the paint adhered to the dual-purpose roll 8, and a blade 6 for scraping off the paint adhered to the doctor roll 5, causing the paint of the paint pan 9 to adhere to the dual-purpose roll 8, This is supplied to the surface of the steel strip S.

[0005] In the coating apparatus disclosed in Japanese Patent Publication No. 60-56552, the pickup roll and the applicator roll rotate in a so-called natural manner, that is, both rolls rotate in opposite directions to each other. Since the two peripheral surfaces move in the same direction at the position where the surfaces meet, cavitation and filamentation occur in the exit region of the roll gap between the two rolls, and bubbling and yarn phenomena occur due to air mixing. Then, a streaky unevenness, that is, build-up occurs in the paint adhered to the surface of the applicator roll due to the threading phenomenon. All the paint adhered to the surface of the applicator roll is not transferred to the steel strip, but the remaining paint solidifies over time on the surface of the applicator roll, leaving a streak-like unevenness. A certain paint is transferred to the surface of the steel strip, causing poor painting.

In the coating apparatus described in the above-mentioned document, the pick-up roll and the dual-purpose roll rotate in opposite directions to each other. And uneven coating is transferred to the surface of the steel strip to cause coating failure.

In view of the above, Japanese Patent Publication No. 3-76188 proposes a coating apparatus in which the smoothness of the coating film surface in these coating apparatuses is prevented and the pick-up property of the coating is improved.

[0008]

[Problem to be Solved by the Invention] This coating apparatus is shown in FIG.
As shown in FIG. 5, a transfer roll 4 adjacent to the applicator roll 3 with a required gap and a doctor roll 5 adjacent to the transfer roll 4 with a required gap are placed in the rotation direction of the applicator roll 3. The arrangement is such that the doctor roll 5 is disposed downstream of the pickup roll 2 and the doctor roll 5 is provided with a blade 6 whose cutting edge is in contact with the backup roll 1, the applicator roll 3, the transfer roll 4 and the doctor roll 5. , And the pickup roll 2 is driven to rotate in a direction opposite to these rolls.

In this coating apparatus, since the rolls rotate in the same direction, the unevenness of the coated surface is reduced, which is effective in preventing defective coating. However, the structure of the apparatus is complicated by increasing the number of rolls. There is a problem that the cost is high.

[0010] In coating the front and back surfaces of the steel strip with a paint or a resin using an S-type roll coater type coating apparatus, in particular, the above-described build-up is performed using an applicator roll disposed on the back side of the steel strip. There is a problem that the phenomenon easily occurs. This is thought to be due to the fact that the paint or resin flows to the applicator roll under the influence of gravity.

The present invention has been made in view of the above-mentioned problems, and provides a roll coater type coating apparatus capable of stably preventing the occurrence of coating defects on the front and back surfaces of a steel strip with a simple configuration. That is.

[0012]

In order to achieve the above object, a roll coater type coating apparatus according to the present invention has a lower portion which is close to a pickup roll dipped in paint in a paint pan with a required gap. In a coating apparatus in which the arranged applicator roll is wound on a backup roll and is in contact with a continuously running steel strip, a position in contact with only the outer peripheral surface of the applicator roll immediately after the paint is transferred to the steel strip. A roll coater type coating apparatus , further comprising a roll surface polishing apparatus.

[0013]

According to the roll coater type coating apparatus of the present invention, an applicator roll whose lower part is disposed close to a pickup roll dipped in paint in a paint pan with a required gap is wound around a backup roll. in the coating apparatus us solve configuration that Sessu the steel strip traveling continuously, to a position in contact only with the outer peripheral surface of the applicator roll immediately after the transfer of the coating to the steel strip, since the disposed surface of the roll polishing apparatus, The outer peripheral surface of the applicator roll always forms a smooth surface.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a diagram showing the configuration of the roll coater type coating apparatus of the present invention.

In the drawing, reference numeral 1 denotes a backup roll around which a steel strip S to be coated is wound. The backup roll 1 comes in contact with the surface of the steel strip S in order to apply paint to the surface of the steel strip S wound around the backup roll 1. The applicator roll 3a is disposed close to the pickup roll 2a, the lower part of which is dipped in the paint in the paint pan 9a, with a required gap. A pickup roll 2b, an applicator roll 3b, and a paint pan 9b for applying paint to the back surface of the steel strip S are provided downstream of the backup roll 1.
Are disposed in the same manner as described above. Reference numerals 7a and 7b denote, for example, buffing rolls arranged so that the respective applicator rolls 3a and 3b are in contact with the outer peripheral surface immediately after transferring the paint to the surface of the steel strip S, and transfer the paint to the surface of the steel strip S. The outer peripheral surfaces of the applicator rolls 3a and 3b immediately after the polishing are constantly polished. Reference numeral 10 denotes a support roll.

The roll coater type coating apparatus according to the present invention has the configuration as described above, and the paint in the paint pan 9a includes the pickup roll 2a and the applicator roll 3a.
And is attached to the surface of the steel strip S. At this time, paint having streak-like unevenness due to the build-up phenomenon remains on the outer peripheral surface of the applicator roll 3a, but the remaining paint is constantly removed by the polishing roll 7a.
Since the outer peripheral surface of “a” maintains a smooth surface, it is possible to prevent the transfer of the coating having the streak-like unevenness to the surface of the steel strip S. In addition, the applicator roll 3b disposed on the downstream side of the backup roll 1 can also prevent the transfer of the striped uneven paint to the back surface of the steel strip S in the same manner.

Incidentally, a polishing roll for buffing a roll diameter of 100 mm is installed in a roll coater type coating apparatus under the following conditions, and the surface roughness of the applicator roll is constantly polished to 1 μm and a steel strip having a thickness of 1 μm is provided. According to the roll coater type coating apparatus of the present invention shown in FIG. 1 in which the front and back surfaces are coated, the roll coater type coating apparatus shown in FIG. Was reduced to 5%.

The conditions for each part are as follows: pickup roll: roll diameter φ300 mm, rotation speed 50 rpm, applicator roll: roll diameter φ270 mm, rotation speed 160 rpm, backup roll: roll diameter φ1000 mm, peripheral speed line synchronization, pickup roll and applicator roll Gap: 0.4 mm, paint is acrylic resin paint.

[0019]

As described above, the roll coater type coating apparatus of the present invention is always provided with the roll surface polishing apparatus which comes into contact with the outer peripheral surface immediately after the applicator roll transfers the paint to the steel strip. The paint remaining on the outer peripheral surface of the applicator roll is removed and a smooth surface is maintained, so that the paint with the remaining unevenness solidifies and the uneven paint with streaks is transferred to the steel strip surface. Can be prevented. Therefore, a beautiful coated steel plate can be stably manufactured, and the non-defective product rate is improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a roll coater type coating apparatus of the present invention.

FIG. 2 is a view showing a configuration of a first conventional roll coater type coating apparatus.

FIG. 3 is a diagram showing a configuration of a second conventional roll coater type coating apparatus.

FIG. 4 is a view showing a configuration of a third conventional roll coater type coating apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Backup roll 2a Pickup roll 2b Pickup roll 3a Applicator roll 3b Applicator roll 7a Polishing roll 7b Polishing roll 9a Paint pan 9b Paint pan S Steel strip

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B05C 1/00-1/16 B05D 1/28

Claims (1)

(57) [Scope of request for utility model registration] 1. An applicator roll whose lower part is disposed close to a pickup roll dipped in paint in a paint pan with a required gap in contact with a continuously running steel strip wound around a backup roll. A roll coater type coating apparatus, characterized in that a roll surface polishing apparatus is provided at a position in contact with only the outer peripheral surface of the applicator roll immediately after the paint is transferred to the steel strip.