JP2665795B2 - Roll coating method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for applying a coating liquid to a roll surface.

(Prior Art) For example, in a copying machine, a method of uniformly charging a photosensitive drum by rotating a charging roll while contacting the photosensitive drum has been studied.

As shown in FIG. 4, the charging roll has a form in which a cored bar 102 protrudes from both ends of a rubber roll body 100.

In this charging roll, a coating film 104 such as a resin is formed on the surface of the roll body 100, and the coating film 104 is uniform and thin (for example, several microns to several tens of Therefore, as a method of forming the coating film 104, a dip method in which the entire roll is immersed in a coating liquid 106 has been adopted as shown in FIG. . This is the coating liquid
This is because a uniform and thin coating film can be formed on the roll surface by controlling the liquid viscosity of the roll 106 or by controlling the pulling speed when the roll is dipped in the coating liquid 106 and then pulled vertically. is there.

(Problems to be solved by the invention) However, in this method, the entire surface of the roll is
That is, in order to make the coating film uniform at one end side and the other end side, it is necessary to perform the immersion operation in the coating liquid 106 at least twice with the roll direction reversed. In addition, there is a problem in that the coating liquid 106 is applied to the cored bar 102 that does not need to be applied.

Therefore, as shown in FIG. 5, a method is used in which a cap 108 is fitted to the cored bar 102 to mask the same portion, and a roll is dipped in the coating liquid 106 in this state (in this case, the cap 108 is It is necessary to fit each of the metal core portions 102 at both ends), but in this case, it is necessary to manually fit and remove the cap 108 every time the dipping process is performed, so that the work becomes troublesome. Coating liquid
It is not possible to automate 106 coating processes, and it is difficult to increase production efficiency.

(Means for Solving the Problems) The present invention has been made to solve such problems, and a gist of the present invention is to provide a roll having a cored bar at an end of a roll body formed of an elastic material. A method of applying a coating liquid to a surface portion of the roll body, wherein the coating liquid is supplied to the surface of the paint roll, and the paint roll and the roll body of the roll to which the coating liquid is applied are both coated. The rolls are brought into contact with each other in a state where the axes of the rolls are inclined so as to intersect at a predetermined angle, and in this state, the two rolls are rotated and the rolls are relatively displaced in an oblique direction with respect to the axis of the paint roll. And applying a coating liquid to the surface of the roll body.

(Effects and Effects of the Invention) As described above, the present invention uses a paint roll as a coating liquid application unit, contacts the main body of the roll as an object to be applied with the paint roll, and rotates and relatively moves them. Then, a coating liquid is applied. Therefore, it is not necessary to mask the metal cores at both ends when applying the coating liquid. Therefore, there is no need to insert or remove the gaps in these cored portions, which makes it possible to automate the coating liquid application step, thereby further improving the production efficiency.

The present invention is characterized in that a paint roll and a roll as an object to be applied are brought into contact with each other in an inclined state so as to intersect with each other, and are relatively moved in an oblique direction.

When applying a coating liquid to a roll as an application object using a paint roll, a generally conceivable method is to place the roll as an application object on the surface of the paint roll in a direction where its axis is parallel, This is a method in which the two rolls are rotated while keeping their positions fixed while maintaining the relative positions of the two rolls.

However, when the present inventor conducted an application experiment of a coating liquid by such a method, it was found that there were the following problems.

That is, in this method, it is difficult to make the roll and the paint roll completely parallel, and when the parallelism is not achieved, the coating film is formed on one end side and the other end side of the roll. The film thickness becomes uneven.

In addition, in this method, it is difficult to press or contact the surface of the roll with a uniform pressure on the surface of the paint roll over its entire length. In addition, problems such as uneven application thickness of the coating liquid on the inflow side and the outflow side of the roll and the paint roll occur.

In order to solve such a problem, the method of the present invention is to contact the paint roll with the roll as an object to be applied in a tilted state, and to relatively move the roll in an oblique direction. The problem can be avoided and the coating liquid can be uniformly applied to the roll surface.

In the method according to the invention, the roll contacts the paint roll only partially in the axial and circumferential directions. Therefore, when these two rolls are relatively moved in a diagonal direction while rotating, the contact portion moves spirally in the axial and circumferential directions along the surface of the rolls, and as a result, the coating liquid is applied to the entire surface of the rolls. It is evenly applied.

In the method of the present invention, the length of the paint roll may be shorter than that of the roll to be applied (for example, about 1.5 to 3 times the diameter of the roll to be applied is sufficient). That is, the length of the paint roll can be significantly reduced as compared with the method of making the roll and the paint roll contact in parallel as described above. In the case where the coating liquid is supplied by rotating the paint roll while immersing it in the coating liquid accommodated in the tank, the opening of the tank can be made smaller, thereby reducing the viscosity change of the coating liquid. It is possible to keep it small.

(Example) Next, an example of the present invention will be described in detail with reference to the drawings.

In FIG. 2, reference numeral 10 denotes a support plate, on one side of which a guide rail 12 is formed in a horizontal direction, and a fitting portion 16 of a slide body 14 is slidably fitted on the guide rail 12. . A projecting piece 18 is provided on the slide body 14, and a male screw shaft 20 is screwed into a female screw hole of the projecting piece 18. The male screw shaft 20 is a bearing 2 provided on the support plate 10.
It is rotatably supported by the motor 2 and 24, and is connected at one end to a motor 28 by a transmission member 26, and is driven to rotate by the motor 28.

A support piece 30 is provided at one end of the slide body 14, and a center pin 36 that rotatably supports a core metal part 34 of a roll (charging roll) 32 is attached to the support piece 30. Here, the roll 32 is formed by integrally molding a rubber material such as silicon rubber mixed with conductive powder to an outer diameter of about 12 mm on the outer peripheral surface of a steel core bar except for both ends thereof.

At the opposite end of the slide body 14, a motor 38 is fixed laterally, and its rotating shaft 40 is connected to a horizontally arranged roll 32.
Is connected to the other metal core part.

Below the slide body 14, a paint roll 41 is arranged horizontally and in a direction forming a predetermined angle (here, 45 °) with respect to the roll 32. Paint roll 41, tank 42
It is rotatably provided in a state where a part thereof is immersed in a coating liquid (here, a conductive coating liquid mainly composed of N-methylmethoxylated nylon) 44 contained therein,
Further, at one end side, it is connected to a motor (not shown) via a pulley and a transmission member 46 wound around the pulley.

The tank 42 is supported on a support base 48, and the support base 48 is configured to be moved up and down by an elevating device such as a cylinder.

Next, the coating liquid is applied to the surface of the roll 32 using this device.
The method of applying 44 will be described.

First, the support base 48 is raised in a state where the slide body 14 is moved rightward in FIG. 2, and the paint roll 41 is brought into contact with the surface of the roll 32. At this time, the roll 32 contacts the surface of the paint roll 41 at the left end of the roll body 35 in the drawing. This is because the moving end of the slide body 14 is determined in advance as such.

Next, while the roll 32 is rotated by the motor 38 together with the paint roll 41, the male screw shaft 20 is rotated by the motor 28, and the slide body 14 is slowly moved to the left in FIG. Then, the contact portion of the roll 32 with the paint roll 41 gradually moves in the circumferential direction and the axial direction of the roll 32. That is, the contact portion moves from the right end portion of the roll 32 along the surface of the roll 32 while drawing a spiral trajectory in the left end direction. If the rotation speed of the roll 32 and the moving speed of the slide body 14 are set so that the pitch of the spiral track is sufficiently small, the coating liquid 44 is uniformly applied to the surface of the roll 32. .

If the rotation direction of the roll 32 and the paint roll 41 and the feed direction of the roll 32 are set to the directions indicated by the arrows in FIG. 1, that is, the directions in which the contact portions rub, the coating film is formed more uniformly. It has been confirmed by experiments by others.

According to the method of this example, the coating liquid 44 can be applied only to the main body 35 of the roll 32, and therefore, there is no need to fit a mask member such as a cap on the cored bar 34. Thus, the step of applying the coating liquid 44 can be simplified, and the step can be automated.

Further, the contact portion of the roll body 35 with the paint roll 41 is only a very small part thereof, and the coating liquid 44 is applied to the entire surface of the roll body 35 by gradually moving the part. Therefore, it is possible to apply the coating liquid 44 evenly on the surface as compared with the case where the roll body 35 is brought into contact with the paint roll 41 over the entire length and the coating liquid 44 is applied as shown in FIG. it can.

As described above, when the coating liquid 44 is applied to the surface of the roll body 35 by the paint roll 41, it is usually considered that the two rolls 41 and 32 are set to be parallel to each other and the two rolls are parallel to each other as shown in FIG. It is a method of rotating,
In this case, the coating liquid 44 is unevenly applied to the surface of the roll body 35 (see the attached reference photograph).

On the other hand, according to the above method, such a problem does not occur.

Although the embodiments of the present invention have been described in detail, the present invention can be implemented in other modes.

For example, in the above example, the roll is moved in the axial direction (A direction in FIG. 1), but it is also possible to move the roll in the directions of B and C in FIG. In some cases, it is possible to move the paint roll side with the roll fixed. The roll may be moved not only in the horizontal direction but also in another direction.

Further, as a means for supplying the coating liquid to the paint roll, another method is used, for example, a method of storing the coating liquid in a space defined by a partition plate and supplying the coating liquid onto the paint roll from the lower opening. It is also possible to apply the present invention to a roll other than the charging roll, and the present invention is based on the knowledge of those skilled in the art in various aspects without departing from the gist thereof. It is possible to implement.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a roll coating method according to an embodiment of the present invention, and FIG. 2 is a perspective view showing an apparatus for implementing the method. FIG. 3 is a comparative example diagram for comparison to explain the features of the method, FIG. 4 is a diagram showing a charging roll as an example of a roll, and FIG. 5 is a conventional diagram of a coating liquid applied to the roll. FIG. 3 is an explanatory view of a coating method of (1). 32: Charging roll, 34: Core part 35: Roll body, 41: Paint roll 44: Coating liquid

Claims (1)

(57) [Claims] 1. A method of applying a coating liquid to a surface portion of a roll body of a roll having a cored bar at an end of the roll body formed of an elastic material, wherein the coating liquid is applied to a surface of a paint roll. While supplying
The paint roll and the roll body of the roll as a coating liquid application target are brought into contact with each other in a state where the axes of the two rolls are inclined so as to intersect at a predetermined angle,
A roll coating method comprising applying a coating liquid to the surface of the roll body by rotating both rolls in that state while moving the rolls relative to an oblique direction forming a certain angle with respect to the axis of the paint roll. .