JP6601447B2 - Coating liquid splash prevention jig and roll coater - Google Patents

Description

The present invention relates to a roll coater having an applicator roll for applying a coating liquid to the surface of a strip-like body such as a steel sheet that is continuously conveyed, and prevents the coating liquid from scattering from the applicator roll. Regarding technology.
The roll coater includes a two-roll natural rotary coater composed of a pick-up roll and an applicator roll, and a three-roll coater equipped with a measure roll for adjusting the amount of coating liquid pumped up by the pick-up roll. In any system, the present invention can be applied to any roll coater having an applicator roll.

For example, in a two-roll natural rotating coater, the coating liquid in the coater pan is pumped up by the pickup roll, and the coating liquid that has moved to the contact surface (transfer section) with the applicator roll as the pickup roll rotates is picked up from the pickup roll and applicator roll. The nip pressure is transferred to the applicator roll while being squeezed to a predetermined film thickness. Thereafter, the coating liquid transferred to the applicator roll is moved to the contact surface with the object to be coated along with the rotation of the applicator roll, whereby the target coating liquid is continuously transferred from the applicator roll.
At this time, the higher the peripheral speed of the pickup roll and the applicator roll and the higher the viscosity of the coating liquid, the greater the possibility that the coating liquid will scatter from the applicator roll. And when a coating liquid scatters from an applicator roll, there exists a possibility that the scattered coating liquid may adhere to a to-be-coated object, and the problem that a to-be-coated object may become a bad appearance may generate | occur | produce.

As a countermeasure against the scattering of the coating liquid, a method of suppressing the pick-up roll peripheral speed or applicator roll peripheral speed or setting the coating liquid viscosity to an extremely low viscosity of 1 to 10 mPa · s can be considered.
However, the method of adjusting the roll peripheral speed and coating liquid viscosity slows down the operation speed and affects the adhesion amount control and appearance stabilization. In many cases, it is difficult to determine operating conditions with priority.
Here, there is a method of covering the pickup roll with a cover and preventing scattering from the pickup roll (see Patent Document 1). However, the method of covering the roll with a cover to prevent scattering often makes it difficult to install, remove and adjust the cover during operation.

  On the other hand, Patent Document 2 proposes preventing the coating liquid from scattering from the applicator roll with a simple jig. The jig described in Patent Document 2 employs a plate-like jig processed into a bowl shape to prevent the coating liquid adhering to the side surface of the applicator roll from scattering, and the end face of the bowl-shaped portion of the jig Is placed on the edge of the roll surface such that the saddle-shaped jig is brought into contact with the roll side surface. This prevents the coating liquid adhering to the roll side surface from moving in the roll circumferential surface direction, thereby preventing the coating liquid from scattering from the applicator roll.

JP 2014-94358 A JP 2013-126655 A

Since the saddle-shaped jig is a plate-shaped jig, it can be easily fixed to a bearing portion of a roll. For this reason, the saddle jig is easy to install. However, the saddle-shaped jig has a problem that it is likely to be displaced in the circumferential direction of the roll due to wear or vibration.
This invention is made | formed in view of the above points, and it aims at preventing scattering of the coating liquid from an applicator roll more reliably with a simple jig | tool.

In order to solve the problem, the coating liquid scattering prevention jig of one aspect of the present invention is a roll in which the coating liquid is transferred from the pickup roll to the applicator roll, and the coating liquid is transferred from the applicator roll to the surface of the belt-like body. In the coater, a coating liquid scattering prevention jig for preventing scattering of the coating liquid from the rotating applicator roll, wherein the coating liquid scattering prevention jig is provided at an edge portion of the applicator roll,
A side surface contact portion that contacts the side surface of the applicator roll, and a peripheral surface contact portion that extends from the side surface contact portion in the roll axial direction and contacts the peripheral surface of the applicator roll,
The contact surface that contacts the roll peripheral surface in the peripheral surface contact portion has a concave curved surface shape that follows the surface shape in the circumferential direction of the contact peripheral surface.

According to one aspect of the present invention, the jig is small and easy to handle, and the contact surface of the peripheral surface contact portion is formed into a concave curved surface shape following the peripheral surface shape of the applicator roll. Since positioning is performed simply by bringing the surface into close contact with the surface, adjustment and removal are simple.
In addition, since the contact surface shape of the peripheral surface contact portion follows the roll shape, the adhesiveness with the surface (circumferential surface) of the roll is improved, so that the jig can be displaced during installation or in use. Can be prevented. As a result, it is possible to more reliably prevent the coating liquid from scattering from the applicator roll.

It is a side view which shows the installation position of the roll coater and coating liquid scattering prevention jig which concern on embodiment based on this invention. It is a perspective view which shows a coating liquid scattering prevention jig | tool. It is a figure which shows the installation position of the coating liquid scattering prevention jig seen from the roll lower part. It is a figure which shows another example of a coating liquid scattering prevention jig | tool.

Next, embodiments of the present invention will be described with reference to the drawings.
In the following description, a two-roll natural rotary coater type roll coater will be described as an example, but the coating liquid scattering prevention jig of the present embodiment is also applicable to a three-roll type roll coater. .
Here, the roll coater is used for applying the coating liquid to the surface of the belt-like body being conveyed, such as post-treatment (chemical conversion treatment, chromate-free treatment) on the surface of the hot-dip galvanized steel sheet. In the following description, the case where the belt-like body to be coated is a steel plate will be described as an example.

<Roll coater>
As shown in FIG. 1, the roll coater 1 of the two-roll natural rotary coater system of the present embodiment includes a coater pan 10, a pickup roll 20, and an applicator roll 30.
A target coating solution 11 is stored in the coater pan 10. The coater pan 10 is appropriately supplemented with a coating liquid 11 by a coating liquid circulation facility (not shown).
The pickup roll 20 is arranged so that the lower part of the roll is immersed in the coating liquid in the coater pan 10. And the pick-up roll 20 draws up the coating liquid in the coater pan 10 with rotation. FIG. 1 illustrates the case where the pickup roll 20 rotates counterclockwise.

  The applicator roll 30 contacts the peripheral surface of the pick-up roll 20 with a predetermined nip pressure, and the contact surface serves as a transfer portion S0 from the pick-up roll 20 and moves to the position of the transfer portion S0. The coating liquid is transferred to the peripheral surface 30 </ b> A of the applicator roll 30 while being narrowed to a predetermined film thickness by the nip pressure. The coating liquid transferred to the applicator roll 30 moves to the steel plate 50 side as the applicator roll 30 rotates, and is continuously applied to the surface of the steel plate 50. Since the present embodiment is a natural rotation coater system, in the example shown in FIG. 1, the applicator roll 30 rotates clockwise, and the coating liquid transferred from the pickup roll 20 at the transfer unit S0 is rotated by the roll 30. Accordingly, the steel plate 50 moves to the steel plate 50 side (left side in FIG. 1) while moving downward, and further moves from the lowest position of the roll 30 to the steel plate 50 side, and then moves from below to above. During this time, the coating liquid is applied to the steel plate 50.

<Coating liquid splash prevention jig>
(Jig structure)
The coating liquid scattering prevention jig 60 of the present embodiment includes a side surface contact portion 60A and a circumferential surface contact portion 60B.
The side surface contact portion 60 </ b> A has a side surface contact surface 60 </ b> Aa that extends in the roll radial direction from the roll edge portion E and contacts the side surface of the applicator roll 30. The side contact surface 60Aa has a flat surface shape.

The peripheral surface contact portion 60B has a peripheral surface contact surface 60Ba that extends from the side surface contact portion 60A along the roll peripheral surface 30A in the roll axis direction and contacts the peripheral surface of the applicator roll 30.
Here, the edge portion E of the roll 30 is an axial end position of the roll circumferential surface 30A, and is a boundary portion (corner portion) between the roll side surface 30B and the roll circumferential surface 30A.
The peripheral surface contact surface 60Ba has a concave curved surface shape that follows the surface shape in the circumferential direction of the contact peripheral surface 30A. The concave curved surface shape is, for example, a cylindrical surface shape. The curved surface shape is preferably the same as the curved surface shape of the roll circumferential surface 30A with which the circumferential surface contact surface 60Ba abuts, but there may be a slight difference in curvature from the curved shape of the roll circumferential surface 30A with which the circumferential surface abutment surface 60Ba abuts. .

  The peripheral surface contact surface 60Ba of the present embodiment has a quadrangular shape when viewed from the front, and the boundary line 61 of the side surface contact portion 60A and the second boundary line 62 (roll) facing the boundary line 61 in the roll axis direction. The side facing the axial center is set so as to be parallel. The boundary line 61 and the second boundary line 62 are designed to face the circumferential direction of the applicator roll 30 when the jig 60 is installed on the roll 30, and the boundary line 61 and the second boundary line 62 are designed. However, the peripheral surface contact surface 60Ba has a concave curved surface shape because it is designed to have a curvature equal to the curvature along the circumferential direction of the peripheral surface of the applicator roll 30.

The second boundary line 62 may be a line position inclined in the roll axis direction from the circumferential direction of the peripheral surface of the applicator roll 30. What is necessary is just to design to the curvature same as the curvature of the surrounding surface of the roll 30 to contact | abut.
Further, the edge 63 facing the upstream side in the rotation direction of the applicator roll 30 (the transfer portion S0 side) on the peripheral surface contact surface 60Ba has a contour extending along the roll axis direction as shown in FIG. With respect to the imaginary line K parallel to the roll axis direction passing through the roll edge part E at the end, the applicator roll 30 from the imaginary line K as it approaches the roll axis direction center side from the roll edge part E side. The separation distance to the upstream side in the rotation direction is set to be large.

In the present embodiment, as shown in FIG. 3, the side 63 that is an end is set in a straight line shape when viewed from the front, and the roll center side of the side 63 with respect to the imaginary line K Side). The side 63 as an end in the front view is directed to the upstream side in the rotation direction of the roll with respect to the imaginary line K. The crossing angle α between the two is preferably 30 degrees or more and 60 degrees or less, more preferably 40 degrees. More than 50 degrees.
In the present embodiment, since the peripheral surface contact surface 60Ba is set in a square shape when viewed from the front, the side 64 that is the other end facing the downstream side in the roll rotation direction is also the side 63 that is the end. However, the inclination of the side 64 is not particularly limited.
In FIG. 2, the sides 63 and 64, which are the two end portions, have concave curves because they are inclined in the roll rotation direction as described above.

(Jig installation position)
As shown in FIG. 1 which is a side view seen from the roll axis direction, the coating liquid scattering prevention jig 60 of the present embodiment is installed at the edge E of the applicator roll 30 and is picked up in the roll circumferential direction. It is installed in a range from a transfer portion S0 where the coating liquid is transferred from the roll 20 to a position S1 where the coating liquid is transferred from the applicator roll 30 to the steel plate 50.
The installation position of the coating liquid scattering preventing jig 60 is preferably in the range from the transfer portion S0 to the lowest position of the roll as viewed from the roll axis direction. FIG. 1 shows an example installed at the bottom. At the position of the roll peripheral surface approaching the steel plate 50 from the lowest position, the coating liquid that is too close to the steel plate 50 and splashes from that position is mainly directed to the steel plate 50 side due to the centrifugal force due to the rotation of the roll. is there. More preferably, it is a range of a depression angle β of 60 degrees or less with respect to the horizontal line H passing through the roll central axis. FIG. 1 shows an example in which the depression angle β is 90 degrees.

Here, the image is transferred from the pick-up roll 20 to the peripheral surface of the applicator roll 30 at the transfer portion S0 position. As shown in FIG. 3 when the roll is viewed from below, a portion of the roll peripheral surface 30A on the axially central portion side. Becomes a contact surface to the steel plate 50. The coating liquid scattering prevention jig 60 is installed on the roll edge portion E so as to be positioned outside the contact range with the steel plate 50 in the roll axis direction. At this time, the circumferential surface contact portion 60B is brought into contact with the roll circumferential surface 30A in a surface contact state, and the side surface contact portion 60A is brought into contact with the roll side surface 30B so as to be in surface contact.
Here, the material of the coating liquid scattering prevention jig 60 is not particularly limited, but if it is made of a resin such as nylon (registered trademark), for example, a lightweight jig is obtained.
Further, the coating liquid scattering prevention jig 60 may be fixed by pressing from the roll axial direction or the roll radial direction toward the surface of the applicator roll 30 with a ball screw or the like set on a support (not shown).

<Operation other>
Since the jig 60 is small in size, it is easy to handle, and the jig 60 is secured by fixing the side surface contact portion 60A and the peripheral surface contact portion 60B to the roll side surface 30B and the roll peripheral surface 30A, respectively. Is automatically positioned on the surface of the roll 30 and can be easily attached. As a result, the jig 60 of this embodiment can be easily adjusted and removed.
Moreover, since this jig | tool 60 can be closely_contact | adhered with the surface with respect to the roll 30, even if there exists abrasion and a vibration, the shift | offset | difference in use can be prevented.

Here, according to the knowledge of the inventors, the coating liquid adhering to the applicator roll 30 is transferred to the steel plate 50 at the center side in the roll axial direction in contact with the steel plate 50 on the peripheral surface. On the other hand, the coating liquid tends to remain relatively on the axial end side, and the coating liquid tends to move to the axial end side (edge part E). On the other hand, the coating liquid adhering to the roll side surface 30B moves radially outward (outer peripheral side) by centrifugal force due to rotation of the roll. Then, the coating liquid scatters from the roll edge portion E.
On the other hand, the coating liquid adhering to the axial direction edge part of 30 A of roll peripheral surfaces is wiped off by installing the coating liquid scattering prevention jig | tool 60 of this embodiment in the edge part E of the applicator roll 30. FIG. At the same time, the coating liquid located on the outer peripheral side of the roll side surface 30B is wiped off. The coating liquid wiped off falls downward and is collected in a receiving container 40 arranged separately.

Thus, by wiping off the coating liquid on the roll edge portion E, scattering of the coating liquid from the edge portion E can be prevented.
Further, in the present embodiment, the side 63 formed by the end facing the upstream side in the roll rotation direction of the peripheral surface contact surface 60Ba of the peripheral surface contact portion 60B is shown in FIG. 3 with respect to an imaginary line K parallel to the roll axis direction. In this way, it is tilted upstream in the roll rotation direction. Thus, when wiping off the coating liquid on the end portion side of the roll peripheral surface 30A, the coating liquid can be guided from the peripheral surface to the roll edge portion E side to efficiently escape the coating liquid. .

In the present embodiment, as shown in FIG. 3, the end surface of the side surface contact portion 60A is such that the end surface of the end portion constituting the side 63 and the end surface of the side surface contact portion 60A continuous therewith are flush with each other. Also tilted.
As the inclination α is inclined with respect to the roll axis direction, the guiding effect toward the edge side becomes larger, but the width of the jig 60 along the roll circumferential direction needs to be increased accordingly. For this reason, as above-mentioned, 30 degrees or more and 60 degrees or less are preferable, More preferably, they are 40 degrees or more and 50 degrees or less.

Although an example of the dimension of the jig 60 is shown in FIG. 2, the width of the jig 60 along the roll circumferential direction is set in a range of 30 mm to 100 mm, for example. Increasing the width improves stability when the jig 60 is installed. Further, the length of the peripheral surface contact surface 60Ba of the peripheral surface contact portion 60B in the roll axis direction, and the length of the side surface contact surface 60Aa in the roll radial direction of the side surface contact portion 60A are determined by the dimensions of the applicator roll 30. What is necessary is just to determine according to the range which should be wiped off according to peripheral speed.
Further, the peripheral surface contact portion 60B and the side surface contact portion 60A are set to a thickness that does not allow the wiping coating liquid to get over.

As described above, the coating liquid scattering prevention jig 60 of the present embodiment is easy to adjust and remove, and can also prevent deviation in the axial direction, and change conditions such as roll peripheral speed and coating liquid viscosity. Without appearance, it is possible to prevent the appearance failure caused by the liquid being locally attached to the steel plate 50 due to the coating liquid scattering from the applicator roll 30 to the steel plate 50.
Here, the outline of the side 63 constituting the end facing the upstream side in the roll rotation direction may be, for example, an arc shape as shown in FIG. In this case, the coating liquid is easily guided to the edge portion E side along the arc. The curvature of this arc need not be constant.

For the roll coater 1 of the two-roll natural rotary coater system used for chromate-free treatment that is a post-treatment of the hot-dip galvanized steel sheet 50, the coating liquid scattering prevention jig 60 according to the present invention described in the embodiment, Using the saddle-shaped jig described in Patent Document 2, the prevention of scattering of the coating liquid was confirmed.
The coating liquid scattering preventing jig 60 according to the present invention is as shown in FIG. 2, and the inclination of the end 63 is set to α = 45 degrees with respect to the phantom line K, and is made of nylon (registered trademark). The vertical jig for comparison was made of steel having a thickness of 1 mm.

First, when the saddle-shaped jig was pressed against the roll and the roll was rotated under the above conditions for 24 hours, the plate-shaped saddle-shaped jig was shifted by 5 mm from the originally installed position after 24 hours, and the generated gap The liquid splashed out.
On the other hand, when the coating liquid scattering preventing jig 60 according to the present invention was pressed against the surface of the roll under the same conditions and the roll was rotated for 24 hours, it was not displaced at all from the position where it was originally installed. Therefore, it was found that it contributes to prevention of coating liquid scattering.
As described above, the present invention can prevent the coating liquid from scattering for a long period of time compared to the prior art.

DESCRIPTION OF SYMBOLS 1 Roll coater 10 Coater pan 20 Pickup roll 30 Applicator roll 30A Roll peripheral surface 30B Roll side surface 50 Steel plate (band-like body)
60 Coating liquid splash prevention jig 60A Side contact portion 60Aa Side contact surface 60B Perimeter contact portion 60Ba Perimeter contact surface 61 Boundary line 62 Boundary line 63 Side 64 Side E Edge portion K Virtual line S0 Transfer part α Intersection angle

Claims (3)

Coating to prevent scattering of the coating liquid from the rotating applicator roll in a roll coater that transfers the coating liquid from the pick-up roll to the applicator roll and transfers the coating liquid from the applicator roll to the surface of the band-shaped body A liquid splash prevention jig, wherein the coating liquid splash prevention jig is provided at an edge portion of the applicator roll,
A side surface contact portion that contacts the side surface of the applicator roll, and a peripheral surface contact portion that extends from the side surface contact portion in the roll axial direction and contacts the peripheral surface of the applicator roll,
The contact surface that contacts the roll peripheral surface in the peripheral surface contact portion has a concave curved surface shape that follows the surface shape in the circumferential direction of the roll peripheral surface to be contacted ,
The rotation direction of the applicator roll is set to a direction in which the applicator roll moves upward at the transfer position to the surface of the belt-like body, and the coating liquid scattering prevention jig is set to the lowest position of the applicator roll. Features a coating liquid splash prevention jig.   The end of the contact surface of the peripheral surface contact portion facing the upstream side in the rotational direction of the applicator roll, and the contour of the end portion along the roll axis direction passes through the roll edge portion at the end portion. With respect to a virtual line parallel to the axial direction, the separation distance from the virtual line to the upstream side in the rotational direction of the applicator roll is set so as to increase from the edge portion side of the roll toward the central side in the roll axial direction. The coating liquid scattering prevention jig according to claim 1, wherein the coating liquid scattering prevention jig is provided. A coating liquid is transferred from the pick-up roll to the applicator roll, and the coating liquid is transferred from the applicator roll to the surface of the belt,
A roll coater comprising the applicator roll provided with the coating liquid scattering prevention jig according to claim 1.

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