JP4815006B2 - Roll coater device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a thickness-consistent coating film on various kinds of cylindrical objects, the external peripheries of whose sections are circular. <P>SOLUTION: A roll coater device 1 includes an application roller 2 which makes a paint P, which adheres to an external peripheral surface 2A, adhere to a material H, to which coating is made, to conduct coating. The application roller 2 has: a coating surface part 5 which makes the paint P of the external peripheral surface 2A adhere to the material H, to which coating is made, the part 5 having a diameter 5A; a non-coating surface part 6 which does not make the paint P adhere to the material H to which coating is made, the part 6 having a diameter 6A; and a level difference part 7 which releases the surplus paint through which the coating surface part 5 is connected to the non-coating surface part 6. Furthermore, the level difference part 7 includes a chamfering part 7B which is chamfered in a smooth arc at the end part on the coating surface part 5 side when viewed from the section of the application roller 2. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a roll coater device capable of forming a coating having a uniform thickness on various cylindrical objects having a circular outer periphery.

  For example, the surface of a cylindrical object such as an OA roller used in a copying machine or a printer is coated with various coatings. This type of roller needs to be coated with a uniform coating thickness of, for example, 5 to 100 μm, and the requirements for appearance and dimensional accuracy are very high. For this reason, conventionally, spray coating, which is easy to obtain coating accuracy, has been frequently used.

  However, spray coating has the disadvantages that paint at the time of coating tends to scatter to the outside, increasing the cost of the paint and deteriorating the environment.

  On the other hand, as a method of coating a cylindrical object, various roll coater apparatuses as described in Patent Document 1 below have been proposed. As shown in FIG. 7 (a), the conventional roll coater r includes a paint pan a that contains the paint a1, and an application roller b that receives the paint a1 from the paint pan a and adheres it to the outer peripheral surface b1. Including. The application roller b and the object to be coated d are arranged substantially in parallel with a predetermined gap g. For example, the outer peripheral surface da of the object to be coated d is coated while rotating both in the opposite directions. It is. And if the coating material a1 is applied to the outer peripheral surface da of the to-be-coated object d, the to-be-coated object d and the application roller b will be spaced apart.

  Such a roll coater apparatus r has an advantage that it is possible to prevent scattering of paint such as spray coating. However, in the roll coater apparatus, at the portion where the coating material a1 is repeatedly applied, or at the coating finish position e of the coating material d where the coating material d and the application roller b are separated as shown in FIG. The coating film thickness t tends to increase locally. For this reason, in the coating by the roll coater device, there is a problem that the coating accuracy is lowered as compared with the spray coating.

JP-A-2005-103482

  The present invention has been devised in view of the above problems, and is a roll that can be coated by forming a uniform-thickness coating film on various cylindrical objects having a circular cross-sectional outer periphery. The main purpose is to provide a coater device.

  The invention according to claim 1 of the present invention is a roll coater device for applying a paint to an object to be coated having a circular outer periphery in cross section, the paint pan containing the paint, and the paint pan directly Or an application roller that attaches the paint to the outer peripheral surface via an intermediate roll and applies the paint attached to the outer peripheral surface to the object to be coated, and the application roller is a paint on the outer peripheral surface. In order to escape the coating surface portion having the radius R1 that adheres to the object to be coated, the non-application surface portion having the radius R2 (R2 <R1) that does not cause the coating material to adhere to the object to be coated, and the surplus paint that passes between them. In addition, in the cross section perpendicular to the longitudinal direction of the application roller, the stepped portion and the application surface portion are chamfered by a smooth arc. A roll coater apparatus characterized by in connected.

  The invention according to claim 2 is the roll coater device according to claim 1, wherein the radius of the article to be coated is 7.5 to 15 mm, and the height h1 in the radial direction of the stepped portion is 2 to 15 mm. .

  In the invention according to claim 3, the ratio (h1 / R3) between the height h1 of the stepped portion and the radius R3 of the article to be coated is 0.1 to 0.5 times. It is a roll coater device.

  Further, in the invention according to claim 4, the radius R1 of the application surface portion is 7.5 to 30 mm, and the circumferential angle θ of the application surface portion is 20 to 300 degrees. It is a roll coater apparatus as described in above.

  A fifth aspect of the present invention is the roll coater device according to any one of the first to fourth aspects, wherein a radius R1 of the application surface portion and a radius R2 of the non-application surface portion are constant.

  According to a sixth aspect of the present invention, the radius R1 of the application surface portion is constant, the radius R2 of the non-application surface portion is non-constant, and increases as the distance from the stepped portion increases, and is smoothly connected to the application surface portion. A roll coater device according to any one of claims 1 to 4.

  According to the present invention, the application roller has an application surface portion having a radius that causes the paint to adhere to the object to be coated, a non-application surface portion having a radius that prevents the paint from adhering to the object to be coated, and the surplus paint that connects between them. In addition, in the cross section of the application roller, the stepped portion and the application surface portion are connected by a chamfered portion chamfered with a smooth arc. Such an application roller can smoothly escape surplus paint accumulated in the contact portion with the object to be coated to the non-application surface portion side through the step portion. Therefore, the coating film thickness can be prevented from locally increasing at the position where the coating is finished, and a uniform coating film can be formed.

It is a principal part perspective view of the roll coater apparatus of one Embodiment of this invention. It is sectional drawing of FIG. 1 which abbreviate | omitted hatching. (A) thru | or (e) are sectional drawings explaining the effect | action of this embodiment. It is sectional drawing which shows other embodiment of an application roller. It is sectional drawing showing the roll coater apparatus which shows other embodiment of this invention. (A) And (b) is sectional drawing which shows the form of the comparative example of a level | step-difference part. (A) is sectional drawing which shows the conventional roll coater apparatus typically, (b) is sectional drawing of the to-be-coated object coated by it.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2, the roll coater device 1 according to the present embodiment is used for coating a coating P on the outer surface of an object H whose outer periphery is circular.

  The coating object H is not particularly limited as long as the outer periphery of the cross section is circular, but a paper feeding / conveying roller used in an OA apparatus such as a copying machine or a printer that requires high accuracy in coating film dimensions, Cylindrical objects such as a charging roller, a developing roller, and a driving roller are suitable. In addition, as the coating material P, various materials are selected depending on the use of the article H to be coated, and any material such as an epoxy resin system or a urethane resin system can be adopted regardless of a solvent system or an aqueous system.

  The roll coater device 1 includes a paint pan 3 that contains the paint P, and an application roller 2 that attaches the paint P attached to the outer peripheral surface 2A to the article H to be coated.

  The paint pan 3 has, for example, a box shape with an open upper surface, and the paint P is stored therein. The paint pan 3 is formed with a dimension sufficiently larger than that of the application roller 2 so that a part of the outer peripheral surface 2A of the application roller 2 can be immersed in the paint P.

  As shown in FIG. 2, the application roller 2 of the present embodiment is configured with a cross-section that is not a single-radial circular cross-section as shown in FIG. 7. That is, the application roller 2 includes a coating surface portion 5 having a radius R1 that causes the paint P adhered to the outer peripheral surface 2A of the application roller 2 to adhere to the article H, and a radius that does not cause the paint P to adhere to the article H. The non-application surface part 6 which has R2 (R2 <R1) and the level | step-difference part 7 which connects between the application surface part 5 and the non-application surface part 6 are comprised. The “radius” is a distance from the rotation center O1 of the application roller 2 to the outer peripheral surface 2A of the application roller.

  In the present embodiment, the application surface portion 5 forms a cylindrical surface having a single (constant) radius R1. When the coating object H is applied at a predetermined position, the coating material P adhered to the outer peripheral surface 2A can be adhered to the coating object H.

  In the present embodiment, the non-application surface portion 6 also forms a single (constant) radius R2 and a concentric cylindrical surface with the application surface portion 5. However, the non-application surface portion 6 has a radius R1 of the application surface portion 5 so that the coating material P adhering to the outer peripheral surface 2A does not adhere to the object H when the object H is applied at a predetermined position. It is formed with a sufficiently smaller radius R2. The application roller 2 is supported so that the non-application surface portion 6 does not come into contact with the paint P of the paint pan 3 when the application roller 2 is rotated around the rotation center O <b> 1 during the painting.

  Therefore, the application roller 2 of this embodiment does not attach the coating material P to the article H to be coated using the entire circumference of the outer peripheral surface 2A, but is a part of the outer peripheral surface 2A (smaller than 360 degrees). A coating P is attached to the article H by using a certain application surface portion 5.

  In order to absorb the difference in radius between the application surface portion 5 and the non-application surface portion 6, the stepped portion 7 connects between the two, and at the time of painting, an excess between the application surface portion 5 and the article H to be coated. Provide a space for paint to escape. In the present embodiment, in one application roller 2, one application surface portion 5, one non-application surface portion 6, and two step portions 7 are formed.

  The application roller is supported by a support device (not shown) so as to be rotatable around the rotation center O1 at a predetermined peripheral speed.

  As shown in FIG. 2, in the cross section perpendicular to the longitudinal direction of the application roller 2, the stepped portion 7 includes a linear portion 7 </ b> A extending radially outward from the end portion 6 e of the non-application surface portion 6, and the linear portion 7 </ b> A. It comprises a chamfered portion 7B that is chamfered (R chamfered) with a smooth arc connecting the end portion 5e of the coating surface portion 5. By providing such a chamfered portion 7B, when the application object 2 is separated from the coating surface portion 5 with the rotation of the application roller 2, the surplus paint between the two smoothly moves the chamfered portion 7B. It can move to the non-application surface part 6 through.

  In FIG. 3, an example of the coating method using the roll coater apparatus 1 of this embodiment comprised as mentioned above is shown.

  FIG. 3A shows an initial state when painting is started. In this state, the application roller 2 immerses the application surface portion 5 in the paint pan 3 by rotation, and waits for the paint P to adhere to the outer peripheral surface 2A in advance. Further, the workpiece H is positioned and set at a predetermined position. At this time, the application roller 2 and the object to be coated H are predetermined according to the target coating thickness between the outer peripheral surface HA of the object to be coated H and the outer peripheral surface 2A of the application surface portion 5 of the application roller 2. The rotation centers O1 and O2 are positioned so that the gaps are formed.

  In addition, for example, both ends of the article H to be coated are supported by an appropriate support (not shown), and can be rotated at a predetermined peripheral speed. The application roller 2 is arranged with the non-application surface portion 6 facing the article H in the initial state.

  Next, in this embodiment, the application roller 2 and the workpiece H are rotated around the respective rotation centers O1 and O2 and in the same direction. Thereby, as shown in FIGS. 3B and 3C, the paint P attached to the application surface portion 5 of the application roller 2 can be attached to the outer peripheral surface HA of the article H to be coated. FIG. 2 is also an enlarged view of FIG.

  As the application surface portion 5 of the application roller 2 and the object H to be rotated are rotated, a substantially uniform coating film corresponding to the gap is formed on the surface of the object H to be coated. Thereafter, as shown in FIG. 3 (d), the surface of the application roller facing the object H to be coated is changed from the application surface portion 5 to the non-application surface portion 6. At this time, the application surface portion 5 and the non-application surface portion 6 are connected to the end portion 5e on the application surface portion 5 side via the stepped portion 7 including the chamfered portion 7B chamfered with a smooth arc. While being performed smoothly, the excess paint which existed between the application roller 2 and the workpiece H can be smoothly released from the stepped portion 7 to the non-application surface portion 6 side.

  For this reason, in the coating method using the roll coater apparatus of the present invention, the distance between the rotation centers O1 and O2 (that is, the gap) between the coating object H and the application roller 2 is kept constant and the coating object is maintained. A uniform coating film can be formed on the outer peripheral surface HA of H, and the coating material can be cut smoothly by letting the excess coating material escape to the non-application surface portion 6 side at the finishing position. Further, the stepped portion 7 having the chamfered portion 7B can alleviate an impact when the stepped portion 7 comes into contact with the paint P when entering the paint pan 3, and excessive undulation or scattering of the paint in the paint pan 3. It is preferable in that it can be prevented.

  Thereafter, as shown in FIG. 3 (e), while the non-application surface 6 of the application roller 2 faces the coating object H, the coating object H is separated from the application roller 2. In addition, it is desirable to hold | maintain the to-be-coated article H in the state rotated for the predetermined time, after separating from the application roller 2. FIG. Thereby, the thickness of a non-hardened coating film can be averaged and the variation in a coating film can be suppressed further.

  With the above-described action, according to the roll coater device 1 of the present embodiment, the paint finishes at the finish of the coating of the article H, which effectively increases the local coating thickness. Can be prevented. Therefore, according to the roll coater apparatus 1 of the present embodiment, the object H can be applied with a simple configuration and a uniform coating thickness.

  When the OA roller is applied as in this embodiment, the radius R3 of the article H is generally about 7.5 to 15 mm. In such an embodiment, the radius R1 of the coated surface portion 5 is preferably 7.5 mm or more, more preferably 10 mm or more, and preferably 30 mm or less, more preferably 20 mm or less. When the radius R1 is less than 7.5 mm, the peripheral length of the coating surface portion 5 becomes excessively small and repeated coating is repeated, so that there is a possibility that the coating film becomes uniform and the production efficiency deteriorates. On the other hand, if the radius R1 exceeds 30 mm, the roll coater is unnecessarily large and the production efficiency may be deteriorated.

  Further, as shown in FIG. 2, the circumferential angle θ of the coating surface portion 5 is preferably 20 degrees or more, more preferably 40 degrees or more, and preferably 300 degrees or less, more preferably 180 degrees or less. desirable. When the angle θ is small, the peripheral length of the coating surface portion 5 becomes excessively small, and there is a risk that repetitive coating or a significant decrease in the rotation speed may be forced. On the other hand, if the angle θ is too large, the proportion occupied by the non-application surface portion 6 becomes small, and there is a tendency that excess paint is difficult to escape, and there is a possibility that the time for separating the coated objects after painting may be small.

  Further, the height h1 in the radial direction of the stepped portion 7 (that is, the radius difference R1-R2 between the coated surface portion 5 and the non-coated surface portion 6) is not particularly limited. There is a risk that it will not be possible to escape. For this reason, the height h1 is preferably 2 mm or more, more preferably 3 mm or more. On the other hand, if the height h1 is too large, the center of gravity of the application roller 2 is greatly deviated from the rotation center O1, and it tends to be difficult to rotate at a uniform speed. From such a viewpoint, the height h1 is preferably 15 mm or less, more preferably 10 mm or less.

  From the same viewpoint, the ratio (h1 / R3) between the height h1 of the stepped portion and the radius R3 of the workpiece is preferably 0.1 or more, more preferably 0.2 or more, and still more preferably 0. .3 or more is desirable, and preferably 0.5 times or less is desirable.

  Moreover, when the radius R3 of the workpiece H is set to about 7.5 to 15 mm as in the present embodiment, the curvature radius R4 of the chamfered portion 7B of the stepped portion is preferably 2.0 mm or more, More preferably, it is 3.0 mm or more, preferably 10 mm or less, more preferably 7 mm or less. When the curvature radius R4 is less than 2.0 mm, there is a possibility that the excess paint cannot be released smoothly. On the other hand, if the radius of curvature R4 exceeds 10 mm, the chamfered portion 7B becomes nearly linear, and there is a possibility that the surplus paint cannot be smoothly released. Furthermore, since the radius R2 of the non-application surface portion 6 is relatively small, the center of gravity of the application roller 2 is greatly displaced from the rotation center O1, and it tends to be difficult to rotate at a uniform speed.

  Further, in the above-described coating, the peripheral speed s1 of the application roller 2 and the peripheral speed s2 of the article H to be coated can be variously determined based on the radius R1 of the application surface portion 5, the radius R3 of the article H, and the like. it can. For example, when the peripheral length of the coating object H and the peripheral length of the application surface portion 5 are the same, it is desirable that the peripheral speed s2 of the coating object H is an integral multiple of the peripheral speed s1 of the application roller 2. Thereby, the coating material P can be made to adhere uniformly to the perimeter of the article H to be coated. In consideration of production efficiency, the peripheral speed s2 of the article H is preferably about 2 to 4 times the peripheral speed s1 of the application roller 2.

  Further, the viscosity of the coating P is not particularly limited, but preferably 0.5 dPa · in consideration of an appropriate coating thickness with respect to the adhesion of the coating P to the article H and appearance such as uneven coating. s or more, more preferably 1.0 dPa · s or more, and preferably 20 dPa · s or less, more preferably 10 dPa · s or less.

  FIG. 4 shows still another embodiment of the application roller 2. In this embodiment, there is only one step portion 7 and the radius R2 of the non-application surface portion 6 is formed to be non-constant. In this example, the outer peripheral surface 2 </ b> A of the non-application surface portion 6 has a radius R <b> 2 that increases with distance from the stepped portion 7, and finally increases gradually to a radius R <b> 1 of the application surface portion 5. Since such an application roller 2 can smoothly come into contact with the article H to be coated, the adhesion of the paint at the start of coating is good, and it is useful for making the coating thickness uniform.

  In the roll coater device 1 of each of the embodiments described above, the paint P accommodated in the paint pan 3 is directly adhered to the outer peripheral surface 2A of the application roller 2, but as shown in FIG. Needless to say, the coating material P may be adhered to the outer peripheral surface 2A of the application roller 2 with the intervening material.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the illustrated embodiments, and can be implemented in various forms. For example, in the above-described embodiment, the application roller 2 and the article H to be coated are coated while being rotated in the same direction, but it is of course possible to rotate them in opposite directions.

  By the roll coater apparatus of the present invention having the application roller shown in FIGS. 1 and 2, the object to be coated was coated under the following conditions, and the performance evaluation such as the coating thickness was performed. Further, as a comparative example, as shown in FIG. 7, the application roller has a single radius (R1 = 20 mm) (Comparative Example 1), and the stepped portion is composed of two straight portions as shown in FIG. 6 (a). The same evaluation was performed for the chamfered one (Comparative Example 2) and the one in which the stepped portion was formed only by the straight portion as shown in FIG. 6B (Comparative Example 3). The main specifications are as follows.

Paint: Water-based urethane resin-based paint Material: Aluminum A6063
Radius R3 of the object to be coated: 10 mm (before coating)
Target dry film thickness: 50 μm
Peripheral speed ratio: s2 / s1 = 2.0
Application surface portion circumferential angle θ: 180 degrees Application surface portion radius R1: 20 mm
Non-coated surface radius R2: 15 mm
Step height in the radial direction h1: 5 mm
Curvature radius of R chamfer R4: 3mm
Inclination angle of C chamfered portion (Comparative Example 2): 45 degrees Gap between coated surface portion and workpiece: 0.1 mm
The test method is as follows.

<Appearance inspection>
About the coated object after painting and drying, the repeated coating part and the coating finish part were observed with the naked eye. The evaluation is as follows.
XX: In the coated part / finished part, there is a coating swell or coating sagging part with a width of 5 mm or more in the longitudinal direction. There is a coating swell part or a coating sagging part.

<Fresh accuracy measurement>
The coated object after coating and drying was rotated at a constant speed, and the flare accuracy was measured evenly around 32 locations using a laser measuring device in the cross-sectional direction. The smaller the value, the more uniform the coating thickness.

  As a result of the test, it was confirmed that the examples had better appearance in appearance than the comparative examples, and the coating thickness was kept uniform.

DESCRIPTION OF SYMBOLS 1 Roll coater apparatus 2 Application roller 2A Outer peripheral surface 3 Paint pan 5 Application surface part R1 Application surface part radius 6 Non-application surface part R2 Non-application surface part radius 7 Step part 7A Straight line part 7B Chamfering part 10 Intermediate roll H Coating object P Coating material

Claims (6)

A roll coater device for applying paint to an object having a circular cross-sectional outer periphery,
A paint pan containing the paint;
An application roller that attaches the paint to the outer peripheral surface directly or through an intermediate roll from the paint pan and applies the paint attached to the outer peripheral surface to the object to be coated, and
The application roller includes an application surface portion having a radius R1 for attaching the paint on the outer peripheral surface to the object to be coated, and a non-application surface portion having a radius R2 (R2 <R1) for preventing the paint from being attached to the object to be coated. With a step part for escaping surplus paint that connects between these,
In addition, in the cross section perpendicular to the longitudinal direction of the application roller, the step portion and the coating surface portion are connected by a chamfered portion chamfered with a smooth arc.   The roll coater device according to claim 1, wherein a radius of the object to be coated is 7.5 to 15 mm, and a height h1 in the radial direction of the stepped portion is 2 to 15 mm.   The roll coater device according to claim 2, wherein a ratio (h1 / R3) between the height h1 of the stepped portion and the radius R3 of the workpiece is 0.1 to 0.5 times.   4. The roll coater device according to claim 1, wherein a radius R <b> 1 of the application surface portion is 7.5 to 30 mm, and an angle θ in the circumferential direction of the application surface portion is 20 to 300 degrees.   The roll coater device according to any one of claims 1 to 4, wherein a radius R1 of the application surface portion and a radius R2 of the non-application surface portion are constant.   5. The radius R1 of the coating surface portion is constant, the radius R2 of the non-coating surface portion is non-constant, and increases as the distance from the stepped portion increases and smoothly continues to the coating surface portion. The roll coater device described.

Images