Cleaning device and cleaning method

Abstract

To provide a cleaning device and a cleaning method, which can effectively remove foreign matter even in an object having a recess on a surface.SOLUTION: A cleaning device 1 removes foreign matter X adhering to one surface of a plate-like or film-like object S. The cleaning device includes: a roller-like first cleaning brush 10 which is rotatably disposed with a rotary shaft perpendicular to the conveyance direction of the object S and parallel to the one surface as a center and is brought into contact with the one surface; a second cleaning brush 20; and a cleaning roller 30 which is brought into contact with the one surface while rotating. Each of rotation directions of the first cleaning brush and the cleaning roller in a contact portion with the one surface is a forward direction with respect to the conveyance direction. The rotation direction of the second cleaning brush in a contact portion with the one surface is the opposite direction with respect to the conveyance direction.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a cleaning device and a cleaning method.

Background Art

[0002] In recent years, cleaning devices have been developed for removing foreign substances such as dust adhering to one surface of a glass substrate of a flat panel display (FPD), a printed circuit board on which electronic components are mounted, a resin thin plate, a film material, and the like.

[0003] As such a cleaning device, a cleaning device has been proposed that includes a cleaning brush that rotates in a direction opposite to the conveyance direction of an object and contacts one surface while rotating, and a cleaning roller that rotates in a direction forward with respect to the conveyance direction of the object and contacts the one surface while rotating (see Japanese Patent Application Laid-Open No. 2016-215155).

[0004] By using this cleaning device, relatively large foreign substances of millimeter size can be effectively scraped up by the cleaning brush, and mainly fine foreign substances can be removed by the cleaning roller. Therefore, foreign substances of different sizes can be effectively removed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] While the above-described conventional cleaning device can effectively remove foreign substances adhering to an object having a relatively flat surface, particularly when there are recesses on the surface of the object, foreign substances located in the shade of the recesses tend to be difficult to remove.

[0007] The present invention has been made in view of such inconveniences, and an object thereof is to provide a cleaning device and a cleaning method capable of effectively removing foreign matter even from an object having a concave portion on its surface.

Means for Solving the Problems

[0008] A cleaning device according to an aspect of the present invention is a cleaning device for removing foreign matter adhering to at least one surface of a plate-shaped or film-shaped object, and is rotatably disposed about a rotation axis perpendicular to the conveyance direction of the object and parallel to the one surface, and is in contact with the one surface. A roller-shaped first cleaning brush, a second cleaning brush located downstream of the first cleaning brush, having a rotation axis parallel to the first cleaning brush and contacting the one surface while rotating, and a cleaning roller located downstream of the second cleaning brush, having a rotation axis parallel to the second cleaning brush and contacting the one surface while rotating. The rotation directions of the first cleaning brush and the cleaning roller at the contact point with the one surface are in the forward direction with respect to the conveyance direction, and the rotation direction of the second cleaning brush at the contact point with the one surface is in the reverse direction with respect to the conveyance direction.

[0009] A cleaning method according to another aspect of the present invention is a cleaning method for removing foreign matter adhering to at least one surface of a plate-shaped or film-shaped object. Using the cleaning device of the present invention, the first cleaning brush has a columnar core metal and a brush portion formed by implanting a plurality of hairs on the peripheral surface of the core metal, and the pressure contact amount of the first cleaning brush at the contact point with the object is controlled to be 0.2 mm or more and 1.5 mm or less.

Effects of the Invention

[0010] The cleaning device of the present invention can effectively remove foreign matter even from an object having recesses on its surface. Also, by using the cleaning method of the present invention, foreign matter can be effectively removed even from an object having recesses on its surface.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0012] [Description of Embodiments of the Present Invention] First, the embodiments of the present invention will be listed and described.

[0013] (1) The cleaning device according to one aspect of the present invention is a cleaning device that removes foreign matter adhering to at least one surface of a plate-shaped or film-shaped object, and is rotatably disposed about a rotation axis perpendicular to the conveyance direction of the object and parallel to the one surface, and a roller-shaped first cleaning brush that contacts the one surface, and is located downstream of the first cleaning brush, and a roller-shaped second cleaning brush whose rotation axis is disposed in parallel with the first cleaning brush and that contacts the one surface while rotating, and a cleaning roller that is located downstream of the second cleaning brush and whose rotation axis is disposed in parallel with the second cleaning brush and that contacts the one surface while rotating, wherein the rotation directions of the first cleaning brush and the cleaning roller at the contact portion with the one surface are in the forward direction with respect to the conveyance direction, and the rotation direction of the second cleaning brush at the contact portion with the one surface is in the reverse direction with respect to the conveyance direction.

[0014] When there is a recess in the object, in the cleaning device, first, since the first cleaning brush rotates in the forward direction, foreign matter near the wall on the downstream side of the recess can be scraped out downstream. Since the second cleaning brush located downstream of the first cleaning brush rotates in the reverse direction, it can scoop up and collect or scrape out the foreign matter scraped out by the first cleaning brush and the foreign matter near the wall on the upstream side of the recess. Further, the cleaning roller located downstream of the second cleaning brush can collect the foreign matter remaining on the surface of the object after being scraped out from the recess by the first cleaning brush and the second cleaning brush. Therefore, the cleaning device can effectively remove foreign matter even from an object having a recess on its surface.

[0015] (2) In the cleaning device of (1) above, the ratio of the peripheral speed of the first cleaning brush to the conveyance speed of the object at the contact portion with the one surface is preferably 1.3 times or more and 3.0 times or less. By setting the ratio within the above range, foreign matter can be efficiently scraped out from the recess while suppressing the scattering of foreign matter.

[0016] (3) In the cleaning device of (1) or (2) above, the ratio of the peripheral speed of the second cleaning brush to the conveyance speed of the object at the contact portion with the one surface is preferably 0.1 times or more and 0.5 times or less. By setting the ratio within the above range, foreign matter can be efficiently scraped out from the recess while suppressing the scattering of foreign matter.

[0017] (4) In the cleaning device of any one of (1) to (3) above, it is preferable that the first cleaning brush, the second cleaning brush, and the cleaning roller contact the one surface in a charged state. By charging the first cleaning brush, the second cleaning brush, and the cleaning roller in this way, foreign matter can be efficiently removed by electrostatic adsorption force.

[0018] (5) It is preferable that the object has a recess on the one surface. The cleaning device of the present invention is excellent in removing foreign matter from an object having a recess.

[0019] (6) A cleaning method according to another aspect of the present invention is a cleaning method for removing foreign matter adhering to at least one surface of a plate-shaped or film-shaped object, using the cleaning device of any one of (1) to (5), wherein the first cleaning brush and the second cleaning brush each have a cylindrical core metal and a brush portion formed by implanting a plurality of hairs on the peripheral surface of the core metal, and the pressing amount of the first cleaning brush and the second cleaning brush at the contact portion with the object is controlled to be 0.2 mm or more and 1.5 mm or less.

[0020] When using the cleaning device of the present invention, the cleaning method controls the pressing amount of the first cleaning brush and the second cleaning brush at the contact portion with the object to be 0.2 mm or more and 1.5 mm or less. Therefore, foreign matter can be efficiently scraped out from the concave portion while suppressing the scattering of foreign matter.

[0021] Here, "parallel" means a concept that includes not only exactly parallel but also substantially parallel, in other words, the included angle is within ±10°, preferably within ±5°. Also, "perpendicular" means a concept that includes not only exactly 90° but also substantially perpendicular, in other words, the included angle is within 90° ± 10°, preferably within 90° ± 5°.

[0022] Also, the "pressing amount" means the difference between the distance between the mandrel surface and the object at the contact portion between the cleaning brush and the object and the length of the bristles of the brush portion.

[0023] [Details of Embodiments of the Present Invention] A cleaning device and a cleaning method according to an embodiment of the present invention will be described with reference to the drawings.

[0024] [Cleaning Device] The cleaning device 1 shown in FIGS. 1 and 2 is a cleaning device for removing foreign matter X adhering to one surface of an object S. The cleaning device 1 includes a first cleaning brush 10, a second cleaning brush 20, and a cleaning roller 30, and is arranged in the order of the first cleaning brush 10, the second cleaning brush 20, and the cleaning roller 30 from the upstream side in the conveying direction D (the direction of the white arrow in FIGS. 1 and 2). The cleaning device 1 also includes a guide roller 40 and a conveying mechanism 50.

[0025] [Object] The object S from which foreign matter is removed by the cleaning device 1 is in a plate shape or a film shape. Examples of the object S include a glass substrate of an FPD (Flat Panel Display), a printed circuit board on which electronic components are mounted, a resin thin plate, a film material, and the like.

[0026] The object S preferably has a concave portion S1 on the one surface. The cleaning device 1 is excellent in removing foreign matter from the object S having the concave portion S1.

[0027] The shape, depth, etc. of the concave portion S1 are not particularly limited, but the shape of the concave portion S1 is preferably a columnar shape, a prismatic shape, or a frustum of a cone shape or a frustum of a pyramid shape in which the area of the bottom side of the concave portion S1 is small. Examples of such a concave portion S1 include a columnar shape or the frustum of a cone-shaped via hole. Examples of the dimensions of the via hole include a diameter of 10 μm or more and 5 mm or less, a depth of 1 μm or more and 5 mm or less, and a ratio of the depth to the diameter of 5.0 or less.

[0028] When the shape of the concave portion S1 is columnar or prismatic, the concave portion S1 is composed of a bottom surface S1a and a side surface S1b (see FIG. 3). In such a concave portion S1, the foreign matter X is likely to stay near the boundary between the bottom surface S1a and the side surface S1b. The cleaning device 1 can effectively remove the foreign matter X staying near this boundary. Note that the object S may have a plurality of concave portions S1, and in this case, the shapes, depths, etc. of the plurality of concave portions S1 do not have to be the same.

[0029] Hereinafter, the case where the shape of the concave portion S1 is columnar or prismatic will be taken as an example for continued explanation, but it does not mean that the shape of the concave portion S1 is limited to columnar or prismatic. Further, in FIG. 3, for ease of understanding, a concave portion S1 having a relatively large area of the bottom surface S1a is illustrated and described with respect to the first cleaning brush 10 and the second cleaning brush 20, but the size of the bottom surface S1a of the concave portion S1 is not limited. For example, even a concave portion S1 having a small area of the bottom surface S1a such that the number of bristles of the brush portion 12 of the first cleaning brush 10 and the second cleaning brush 20 that can enter the concave portion S1 at one time is 1 or more and 3 or less, the cleaning device 1 functions effectively.

[0030] The average thickness of the object S is not particularly limited. However, as the lower limit of the average thickness of the object S, for example, 30 μm is preferable, and 50 μm is more preferable. On the other hand, the upper limit of the average thickness of the object S depends on the surface area of the object S. For example, 5 cm is preferable, and 3 cm is more preferable. If the average thickness of the object S is less than the above lower limit or exceeds the above upper limit, it may be difficult to transport the object S. Note that "average" refers to the average value of the amounts measured at any 10 locations. The same applies throughout this specification below.

[0031] The lower limit of the conveyance speed of the object S is not particularly limited. For example, 5 m / min is preferable, and 10 m / min is more preferable. On the other hand, as the upper limit of the conveyance speed of the object S, 30 m / min is preferable, and 20 m / min is more preferable. If the conveyance speed of the object S is less than the above lower limit, the time required for foreign matter removal becomes long, and the removal efficiency of the foreign matter X may decrease. Conversely, if the conveyance speed of the object S exceeds the above upper limit, there is a possibility that the foreign matter X on the surface of the object S cannot be sufficiently adsorbed by the cleaning roller 30.

[0032] Foreign matter X adheres to one surface of the object S before being cleaned by the cleaning device 1. The foreign matter X adhering to the object S is often charged. Hereinafter, the case where the foreign matter X is positively charged will be taken as an example for continued explanation, but the foreign matter X may be negatively charged. If the foreign matter X is negatively charged, the positive and negative of the following charging are reversed. Also, even if the foreign matter X is not charged, the effects of the present invention can be obtained.

[0033] <First cleaning brush> The first cleaning brush 10 is in the shape of a roller and has a cylindrical core metal 11 and a brush part 12 formed by implanting a plurality of hairs on the peripheral surface of the core metal 11. The first cleaning brush 10 is rotatably disposed about a rotation axis perpendicular to the conveyance direction D of the object S and parallel to the surface of the object S, and contacts the surface of the object S. At this time, when passing through the recess S1, the tip of the brush part 12 of the first cleaning brush 10 is configured to contact the bottom surface S1a of the recess S1.

[0034] The rotation direction of the first cleaning brush 10 at the contact portion with the surface of the object S is in the forward direction with respect to the conveyance direction D. The first cleaning brush 10 can be configured to rotate along with the conveyance of the object S, but it is preferably rotationally driven in the forward direction by a driving device. Since the first cleaning brush 10 rotates in the forward direction, as shown in FIG. 3, the foreign matter X staying mainly on the downstream side in the conveyance direction D of the recess S1 is collected by the brush portion 12, or the foreign matter X can be scraped out further downstream in the conveyance direction D by the brush portion 12.

[0035] As the bristles forming the brush portion 12, those to which foreign matter X easily adheres physically are preferable, and examples include fibers made of synthetic resin. Further, as the bristles forming the brush portion 12, those capable of being charged with a charge for adsorbing the foreign matter X adhering to the surface of the object S by the force of an electric field are preferable, and for example, fibers made of synthetic resin containing a conductive material such as carbon black, carbon fiber, metal powder, and metal whiskers can be preferably used.

[0036] The cross-sectional shape of the bristles of the brush portion 12 is not particularly limited, and as the brush portion 12, for example, those having a circular, elliptical, star-shaped cross-sectional shape of the bristles can be used. Further, the outer shape of the bristles of the brush portion 12 is not particularly limited, and as the bristles of the brush portion 12, for example, those having an outer shape such as a linear shape, a wavy curve shape, or a shape formed by combining a curve and a straight line can be used. Note that the larger the surface area of the bristles of the brush portion 12, the easier it is to adsorb the foreign matter X, so as the bristles forming the brush portion 12, for example, those having a star-shaped cross-sectional shape can be preferably used.

[0037] The first cleaning brush 10 preferably contacts the surface of the object S in a charged state. By contacting the first cleaning brush 10 with the surface of the object S in a charged state in this way, the foreign matter X adhering to the surface of the object S is adsorbed onto the surface of the first cleaning brush 10 by the force of static electricity, so that the foreign matter X can be removed more effectively.

[0038] As the lower limit of the voltage applied to the first cleaning brush 10, for example, -800 V is preferable, and -600 V is more preferable. On the other hand, the applied voltage is preferably less than, for example, -200 V, and more preferably -300 V or less. By setting the voltage applied to the first cleaning brush 10 within the above range, it is possible to efficiently remove the positively charged foreign matter X in particular. The reference potential (0 V potential) of the applied voltage is the rotation axis of the first counter electrode roller 16 or the part (stage) where the transport mechanism 50 contacts the object S, which will be described later. The same applies to the reference potential of the applied voltage described hereinafter.

[0039] As the lower limit of the ratio of the peripheral speed of the first cleaning brush 10 to the transport speed of the object S at the contact portion with the surface of the object S, 1.3 times is preferable, and 1.5 times is more preferable. On the other hand, as the upper limit of the above ratio, 3.0 times is preferable, and 2.5 times is more preferable. If the above ratio is less than the above lower limit, there is a possibility that the foreign matter X staying in the recess S1, especially the foreign matter X staying on the downstream side in the transport direction D of the recess S1, cannot be sufficiently removed from the recess S1. Conversely, if the above ratio exceeds the above upper limit, the foreign matter X is likely to scatter, and for example, there is a possibility that the foreign matter X will fall again into another recess S1 on the downstream side in the transport direction D. That is, by setting the above ratio within the above range in this way, it is possible to efficiently scrape out the foreign matter X from the recess S1 while suppressing the scattering of the foreign matter X.

[0040] <Second cleaning brush> The second cleaning brush 20 is located on the downstream side of the first cleaning brush 10. The second cleaning brush 20 is in the shape of a roller and has a cylindrical mandrel 21 and a brush portion 22 formed by implanting a plurality of hairs on the peripheral surface of the mandrel 21. The second cleaning brush 20 is rotatably arranged around a rotation axis perpendicular to the transport direction D of the object S and parallel to the surface of the object S, and contacts the surface of the object S. At this time, when the second cleaning brush 20 passes through the recess S1, the tip of the brush portion 22 is configured to contact the bottom surface S1a of the recess S1.

[0041] The rotation direction of the second cleaning brush 20 at the contact portion with the surface of the object S is opposite to the conveying direction D. In other words, the second cleaning brush 20 is rotationally driven in the reverse direction by a driving device. The second cleaning brush 20 rotates in a direction opposite to the conveying direction D at the contact portion with the surface of the object S. Since the second cleaning brush 20 is rotating in the reverse direction, as shown in FIG. 4, the foreign matter X staying mainly on the upstream side in the conveying direction D of the recess S1 can be collected by the brush portion 22, or the foreign matter X can be scraped out further upstream in the conveying direction D by the brush portion 22.

[0042] Here, the reason for arranging the second cleaning brush 20 downstream of the first cleaning brush 10 will be explained. The first cleaning brush 10 scrapes the foreign matter X further downstream in the conveying direction D. At this time, if the second cleaning brush 20 is arranged downstream of the first cleaning brush 10, the foreign matter X scraped out by the first cleaning brush 10 passes through the second cleaning brush 20 and the cleaning roller 30, and can be collected by these two mechanisms. On the contrary, if the second cleaning brush 20 is arranged upstream of the first cleaning brush 10, the foreign matter X scraped out by the first cleaning brush 10 only passes through the cleaning roller 30, so the recovery efficiency of the foreign matter X may decrease. On the other hand, since the second cleaning brush 20 scrapes the foreign matter X further upstream in the conveying direction D, the scraped foreign matter X may have an opportunity to be collected by the second cleaning brush 20 itself. Therefore, even if the second cleaning brush 20 is arranged downstream of the first cleaning brush 10, it can be collected by the two mechanisms of the second cleaning brush 20 and the cleaning roller 30. For this reason, it is difficult for the recovery efficiency of the foreign matter X to decrease. Therefore, by arranging the second cleaning brush 20 downstream of the first cleaning brush 10, the recovery efficiency of the foreign matter X can be increased.

[0043] The brush part 22 of the second cleaning brush 20 can be configured in the same manner as the brush part 12 of the first cleaning brush 10. Note that the second cleaning brush 20 is preferably the same as the first cleaning brush 10 in terms of material and diameter.

[0044] The second cleaning brush 20 may be brought into contact with the surface of the object S in a charged state. By bringing the second cleaning brush 20 into contact with the surface of the object S in a charged state in this way, the foreign matter X adhering to the surface of the object S is adsorbed onto the surface of the second cleaning brush 20 by the force of static electricity, so that the foreign matter X can be removed more effectively.

[0045] The voltage applied to the second cleaning brush 20 can be the same as the voltage applied to the first cleaning brush 10, and preferably both have the same polarity and equal voltage.

[0046] The lower limit of the ratio of the peripheral speed of the second cleaning brush 20 to the conveyance speed of the object S at the contact portion with the surface of the object S is preferably 0.1 times, more preferably 0.2 times. On the other hand, the upper limit of the above ratio is preferably 0.5 times, more preferably 0.4 times. If the above ratio is less than the above lower limit, there is a possibility that the foreign matter X staying in the concave portion S1, especially the foreign matter X staying on the upstream side in the conveyance direction D of the concave portion S1, cannot be sufficiently removed from the concave portion S1. Conversely, if the above ratio exceeds the above upper limit, the foreign matter X is likely to scatter, and for example, there is a possibility that the foreign matter X will fall again into another concave portion S1 on the upstream side in the conveyance direction D. That is, by setting the above ratio within the above range in this way, the foreign matter X can be efficiently scraped out from the concave portion S1 while suppressing the scattering of the foreign matter X.

[0047] <Cleaning roller> The cleaning roller 30 is located on the downstream side of the second cleaning brush 20. The cleaning roller 30 is arranged with its rotation axis parallel to that of the second cleaning brush 20 and contacts the surface of the object S while rotating.

[0048] The rotation direction of the cleaning roller 30 at the contact portion with the surface of the object S is the forward direction with respect to the conveyance direction D. The cleaning roller 30 may be rotationally driven in the forward direction by a driving device, but may be configured to rotate along with the conveyance of the object S. In the configuration of rotating along, a driving device is not required. The cleaning roller 30 rotates in the forward direction by coming into contact with the object S whose surface is being conveyed.

[0049] The second cleaning brush 20 is disposed downstream of the first cleaning brush 10, and the cleaning roller 30 is disposed downstream of the second cleaning brush 20. That is, the cleaning roller 30 is disposed downstream of the first cleaning brush 10 and the second cleaning brush 20. As described above, the first cleaning brush 10 and the second cleaning brush 20 scrape the foreign matter X in the recess S1 onto the surface of the object S outside the recess S1. Since the cleaning roller 30 mainly collects the foreign matter X on the surface of the object S outside the recess S1, by disposing the cleaning roller 30 downstream of the first cleaning brush 10 and the second cleaning brush 20 in this way, the foreign matter X scraped out of the recess S1 by the first cleaning brush 10 and the second cleaning brush 20 can be efficiently collected.

[0050] The cleaning roller 30 can have a configuration including, for example, a columnar core metal 31, a cylindrical inner layer portion 32 covering the circumferential surface of the core metal 31, and a thin film cylindrical outer layer portion 33 covering the outer peripheral surface of the inner layer portion 32.

[0051] As the material of the inner layer portion 32, an elastic member having conductivity is used. Examples of such an elastic member include polyester-based urethane containing carbon.

[0052] As the material of the outer layer portion 33, those capable of being charged with charges that can adsorb foreign matter X adhering to the surface of the object S by the force of an electric field are preferable. Examples thereof include polyurethanes such as acrylic mixed polyurethane and fluorine mixed polyurethane. By forming the outer layer portion 33 with polyurethane, the abrasion resistance is excellent compared to the case of forming it with silicone resin, butyl rubber, etc., and contamination by plasticizers and low molecular weight substances can be reduced.

[0053] The above acrylic mixed polyurethane means a mixture mainly composed of polyester polyurethane or polyether polyurethane, and further containing (1) thermoplastic polyurethane and silicone-acrylic copolymer resin, (2) acrylic resin (for example, a graft compound in which an aminoethyl group is grafted to the main chain composed of a methacrylic acid-methyl methacrylate copolymer) and thermoplastic polyurethane, or (3) a mixture containing acrylic resin, polyurethane, and a fluorine-based surface coating agent. By using acrylic mixed polyurethane as the material of the outer layer portion 33, the negatively chargeable foreign matter X is easily removed from the surface of the object S. Note that the "main component" is the component with the highest content, for example, a component contained in an amount of 50% by mass or more.

[0054] Also, the above fluorine mixed polyurethane means a mixture mainly composed of polyurethane and containing thermoplastic polyurethane and urethane-fluorine copolymer. By using fluorine mixed polyurethane as the material of the outer layer portion 33, the positively chargeable foreign matter X is easily removed from the object S.

[0055] As the lower limit of the average thickness of the outer layer portion 33, 2 μm is preferable, and 5 μm is more preferable. On the other hand, as the upper limit of the average thickness of the outer layer portion 33, 500 μm is preferable, and 50 μm is more preferable. If the average thickness of the outer layer portion 33 is less than the above lower limit, the surface of the cleaning roller 30 cannot be sufficiently charged, and there is a risk that the adsorption effect of the foreign matter X cannot be sufficiently obtained. Conversely, if the average thickness of the outer layer portion 33 exceeds the above upper limit, there is a risk that good charging characteristics for adsorbing the foreign matter X cannot be obtained.

[0056] The cleaning roller 30 may be in contact with the surface of the object S in a charged state. By bringing the cleaning roller 30 into contact with the surface of the object S in a charged state in this way, the foreign matter X adhering to the surface of the object S is adsorbed onto the surface of the cleaning roller 30 by the force of static electricity, so that the foreign matter X can be removed more effectively.

[0057] As the lower limit of the voltage applied to the cleaning roller 30, for example, -400 V is preferable, and -200 V is more preferable. On the other hand, the applied voltage is, for example, less than 0 V, and preferably -50 V or less. By setting the voltage applied to the cleaning roller 30 within the above range, the positively charged foreign matter X can be removed efficiently. Note that the voltages applied to the first cleaning brush 10, the second cleaning brush 20, and the cleaning roller 30 are preferably of the same polarity.

[0058] <Guide roller> The guide roller 40 shown in FIG. 2 is disposed on the upstream side in the transport direction D from the first cleaning brush 10 and assists in transporting the object S while being in contact with the surface of the object S.

[0059] The guide roller 40 is rotatably disposed parallel to the rotation axis of the first cleaning brush 10. This guide roller 40 rotates along with the transport of the object S. That is, the rotation direction of the guide roller 40 at the contact portion with the surface of the object S is in the forward direction with respect to the transport direction D. Note that the guide roller 40 may be configured to be rotationally driven. For example, by rotationally driving the guide roller 40 so as to be in the forward direction with respect to the transport direction D of the object S, the transport speed of the object S in the cleaning device 1 can be made constant.

[0060] It is preferable that another roller that contacts the surface of the object S on the opposite side across the object S at the position where the guide roller 40 contacts the surface of the object S is provided. In the cleaning device 1, as shown in FIG. 2, as this other roller, one conveying roller 52 of the upstream conveying mechanism 50a described later is used. Hereinafter, the case where the other roller is one conveying roller 52 of the upstream conveying mechanism 50a will be taken as an example and the description will be continued. However, the other roller is not limited to the conveying roller 52. For example, a dedicated conveying roller may be provided as the other roller.

[0061] The guide roller 40 is arranged so as to have a gap between it and the conveying roller 52 such that both surfaces of the object S contact the circumferential surfaces of these two rollers. In the cleaning device 1, by inserting the object S between the guide roller 40 and the conveying roller 52, the traveling direction of the object S can be controlled. For example, when the object S is in the form of a thin film, the tip is likely to bend. Even in such a case, the bending of the tip is suppressed by inserting it between the guide roller 40 and the conveying roller 52, and the tip of the object S can enter easily and surely between the first cleaning brush 10 and the first opposing electrode roller 16 described later.

[0062] The material of the guide roller 40 is preferably one with a small frictional force between it and the object S, and metals, resins, etc. can be used as the material for forming the guide roller 40.

[0063] It is preferable that no other roller that contacts the surface of the object S is arranged between the guide roller 40 and the first cleaning brush 10.

[0064] <Conveying mechanism> The conveying mechanism 50 applies a propulsive force for conveying to the object S. This conveying mechanism 50 has an upstream conveying mechanism 50a arranged upstream of the first cleaning brush 10 in the conveying direction D and a downstream conveying mechanism 50b arranged downstream of the cleaning roller 30 in the conveying direction D.

[0065] (Upstream conveying mechanism) The upstream conveying mechanism 50a is for loading the object S and inserting it into the first cleaning brush 10. As shown in FIG. 1, it has a plurality of belt conveying parts 51. Each belt conveying part 51 has an endless belt 53 wound between a pair of conveying rollers 52 arranged at intervals along the conveying direction D.

[0066] Of the pair of conveying rollers 52, one is a driving roller to which a rotational force is applied, and the other is a driven roller that rotates with the endless belt 53 due to the rotation of the driving roller. The plurality of belt conveying parts 51 are arranged at regular intervals in the horizontal direction perpendicular to the conveying direction D.

[0067] (Downstream conveying mechanism) The downstream conveying mechanism 50b is for unloading the object S that has passed through the cleaning roller 30. Since the downstream conveying mechanism 50b can be configured in the same way as the upstream conveying mechanism 50a, detailed description thereof is omitted.

[0068] <Other configurations> (First foreign object recovery mechanism) As a first foreign object recovery mechanism for recovering the foreign object X attached to the first cleaning brush 10, the cleaning device 1 may have, for example, as shown in FIG. 2, a first dust collecting roller 13, a first scraper 14, and a first foreign object recovery part 15.

[0069] The first dust collecting roller 13 is arranged with its rotation axis parallel to that of the first cleaning brush 10 and contacts the surface of the first cleaning brush 10 in a charged state. It is preferable that the rotation direction of the first dust collecting roller 13 at the contact part with the surface of the first cleaning brush 10 is opposite to the rotation direction of the first cleaning brush 10. By setting the rotation direction of the first dust collecting roller 13 to be opposite to the rotation direction of the first cleaning brush 10 in this way, the foreign object X attached to the first cleaning brush 10 can be efficiently recovered.

[0070] The first dust collecting roller 13 can be made of a conductive material. Examples of the conductive material include metal materials such as stainless steel, copper, and aluminum. When using a conductive material that is prone to oxidation, such as copper or aluminum, as the first dust collecting roller 13, it is preferable to perform a corrosion-resistant plating treatment such as nickel plating or gold plating on the surface of the first dust collecting roller 13.

[0071] Also, the potential of the first dust collecting roller 13 is preferably the same polarity as that of the first cleaning brush 10 and has a larger absolute value. By configuring it in this way, the foreign matter X attached to the first cleaning brush 10 can be efficiently collected.

[0072] The first scraper 14 is, for example, a rectangular plate, and one side forming the rectangle contacts the surface of the first dust collecting roller 13 in the rotation axis direction of the first dust collecting roller 13 (hereinafter, the portion in contact with the first dust collecting roller 13 is also referred to as the "tip portion"). The first scraper 14 is arranged so that its tip portion faces downward, and at the contact position with the surface of the first dust collecting roller 13, it is disposed at a position where the rotation direction of the first dust collecting roller 13 is from bottom to top.

[0073] The first scraper 14 is formed of an elastic body made of a synthetic resin such as thermosetting polyurethane. As the first dust collecting roller 13 rotates, the foreign matter X attached to the surface of the first dust collecting roller 13 is scraped off by the tip portion of the first scraper 14. As a result, the surface of the first dust collecting roller 13 becomes a clean state from which the foreign matter X has been removed.

[0074] The first foreign matter collection part 15 is in a tray shape and is disposed below the tip portion of the first scraper 14. The foreign matter X scraped off by the first scraper 14 falls and is collected into the first foreign matter collection part 15.

[0075] (Second foreign matter collection mechanism) The cleaning device 1 may have, for example, as shown in FIG. 2, a second foreign matter collection mechanism for collecting the foreign matter X adhering to the second cleaning brush 20, such as a second dust collection roller 23, a second scraper 24, and a second foreign matter collection section 25.

[0076] The second dust collection roller 23, the second scraper 24, and the second foreign matter collection section 25 can be configured in the same manner as the first dust collection roller 13, the first scraper 14, and the first foreign matter collection section 15, respectively, and thus detailed description thereof will be omitted. In the cleaning device 1, the second foreign matter collection section 25 is also used as the first foreign matter collection section 15.

[0077] (Third foreign matter collection mechanism) The cleaning device 1 may have, for example, as shown in FIG. 2, a third foreign matter collection mechanism for collecting the foreign matter X adhering to the cleaning roller 30, such as a brush roller 34, a third dust collection roller 35, a third scraper 36, and a third foreign matter collection section 37.

[0078] The brush roller 34 is arranged with its rotation axis parallel to that of the cleaning roller 30 and contacts the surface of the cleaning roller 30 in a charged state. The rotation direction of the brush roller 34 at the contact portion with the surface of the cleaning roller 30 is preferably opposite to the rotation direction of the cleaning roller 30. By setting the rotation direction of the brush roller 34 to be opposite to the rotation direction of the cleaning roller 30 in this way, the foreign matter X adhering to the cleaning roller 30 can be efficiently collected. The brush roller 34 can be configured in the same manner as the first cleaning brush 10, for example.

[0079] The potential of the brush roller 34 is preferably the same polarity as that of the cleaning roller 30 and has a larger absolute value. By setting the potential of the brush roller 34 to be the same polarity as that of the cleaning roller 30 and having a larger absolute value in this way, the foreign matter X adhering to the cleaning roller 30 is likely to move from the cleaning roller 30 to the brush roller 34 at the contact portion. Therefore, the foreign matter X adhering to the cleaning roller 30 can be more reliably collected.

[0080] The third dust collecting roller 35 is disposed parallel to the cleaning roller 30 in terms of the rotation axis and contacts the surface of the brush roller 34 in a charged state. Since the third dust collecting roller 35 can be configured in the same manner as the first dust collecting roller 13, the detailed description is omitted.

[0081] The third scraper 36 is, for example, a rectangular plate, and one side forming the rectangle contacts the surface of the third dust collecting roller 35 over the rotation axis direction of the third dust collecting roller 35. Since the third scraper 36 can be configured in the same manner as the first scraper 14, the detailed description is omitted.

[0082] The third foreign matter collection part 37 is in a tray shape and is disposed below the tip of the third scraper 36. The foreign matter X scraped by the third scraper 36 falls and is collected into this third foreign matter collection part 37.

[0083] (Counter Electrode Roller) The cleaning device 1 may include a first counter electrode roller 16 that contacts a surface opposite to the surface that contacts the first cleaning brush 10 of the object S, a second counter electrode roller 26 that contacts a surface opposite to the surface that contacts the second cleaning brush 20 of the object S, and a third counter electrode roller 38 that contacts a surface opposite to the surface that contacts the cleaning roller 30 of the object S.

[0084] The first counter electrode roller 16 is rotatably disposed at a position where the rotation axis is parallel and opposite to the first cleaning brush 10, the second counter electrode roller 26 is rotatably disposed at a position where the rotation axis is parallel and opposite to the second cleaning brush 20, and the third counter electrode roller 38 is rotatably disposed at a position where the rotation axis is parallel and opposite to the cleaning roller 30.

[0085] The first counter electrode roller 16, the second counter electrode roller 26, and the third counter electrode roller 38 (collectively also referred to as the "counter electrode roller") are in contact with the back surface of the object S in a grounded state. Note that any one or all of the counter electrode rollers may be used while being charged. When charging each counter electrode roller, a voltage having the same polarity but lower than the voltage applied to the first cleaning brush 10 or a voltage with the opposite positive and negative polarities is applied to the first counter electrode roller 16, a voltage having the same polarity but lower than the voltage applied to the second cleaning brush 20 or a voltage with the opposite positive and negative polarities is applied to the second counter electrode roller 26, and a voltage having the same polarity but lower than the voltage applied to the cleaning roller 30 or a voltage with the opposite positive and negative polarities is applied to the third counter electrode roller 38. Thereby, the adsorption effect due to the electric field force of the first cleaning brush 10, the second cleaning brush 20, and the cleaning roller 30 is promoted, and the foreign matter X adhering to the surfaces of the object S on the sides of the first cleaning brush 10, the second cleaning brush 20, and the cleaning roller 30 is more easily adsorbed by the first cleaning brush 10, the second cleaning brush 20, and the cleaning roller 30.

[0086] The counter electrode roller rotates along with the conveyance of the object S. That is, the rotation direction of the counter electrode roller at the contact portion with the back surface of the object S is in the forward direction with respect to the conveyance direction D.

[0087] Part or all of the counter electrode roller is formed of a conductive material. Examples of such a conductive material include metal materials such as stainless steel, copper, and aluminum. The counter electrode roller can be formed only of the conductive material, but as represented by the third counter electrode roller 38 in FIG. 2, a configuration may be adopted in which an outer peripheral surface of a core metal 38a formed of the conductive material is covered with an insulating layer 38b such as a synthetic resin.

[0088] (Unitization) As shown in Fig. 1, in the cleaning device 1, the first cleaning brush 10 and the first foreign matter recovery mechanism are unitized (the first brush unit 1a), the second cleaning brush 20 and the second foreign matter recovery mechanism are unitized (the second brush unit 1b), and the cleaning roller 30 and the third foreign matter recovery mechanism are unitized (the roller unit 1c). The first brush unit 1a, the second brush unit 1b, and the roller unit 1c are each independently configured to be detachable. By configuring each unit to be detachable in this way, the convenience of operations such as discarding the recovered or removed foreign matter X is improved. Also, when it is necessary to replace the type of unit depending on the type of the object S or the foreign matter X, the entire unit can be replaced.

[0089] <Advantages> When the object S has a recess S1, in the cleaning device 1, first, since the first cleaning brush 10 rotates in the forward direction, the foreign matter X near the wall on the downstream side of the recess S1 can be scraped out downstream. The second cleaning brush 20 located on the downstream side of the first cleaning brush 10 rotates in the reverse direction, so it can scoop up and recover or scrape out the foreign matter X scraped out by the first cleaning brush 10 and the foreign matter X near the wall on the upstream side of the recess S1. Further, the cleaning roller 30 located on the downstream side of the second cleaning brush 20 can recover the foreign matter X remaining on the surface of the object S after being scraped out from the recess S1 by the first cleaning brush 10 and the second cleaning brush 20. Therefore, the cleaning device 1 can effectively remove the foreign matter X even from the object S having the recess S1 on its surface.

[0090] 〔Cleaning Method〕 The cleaning method according to an embodiment of the present invention is a cleaning method for removing the foreign matter X adhering to one surface of the plate-shaped or film-shaped object S, and uses the cleaning device 1 of the present invention shown in Fig. 1.

[0091] In this cleaning method, an object S placed on the upstream transport mechanism 50a of the transport mechanism 50 is transported by the upstream transport mechanism 50a, and foreign matter X is removed as one surface thereof passes through the first cleaning brush 10, the second cleaning brush 20, and the cleaning roller 30 in this order.

[0092] At this time, in this cleaning method, the amount of pressure contact at the contact portions of the first cleaning brush 10 and the second cleaning brush 20 with the object S is controlled. The lower limit of the pressure contact amount is 0.2 mm, and 0.4 mm is more preferable. On the other hand, the upper limit of the pressure contact amount is 1.5 mm, and 1.3 mm is more preferable. If the pressure contact amount is less than the lower limit, there is a possibility that the foreign matter X staying in the recess S1 cannot be sufficiently removed from the recess S1. Conversely, if the pressure contact amount exceeds the upper limit, the foreign matter X is likely to scatter, and for example, there is a possibility that the foreign matter X will fall into another recess S1 again. Note that the pressure contact amounts of the first cleaning brush 10 and the second cleaning brush 20 may be equal or different. By controlling them independently, the foreign matter X can be removed more effectively.

[0093] In the control of the pressure contact amount, the first cleaning brush 10 and the second cleaning brush 20 can be moved up and down so that the pressure contact amount becomes constant according to the unevenness of the object S, but the first cleaning brush 10 and the second cleaning brush 20 may be fixed so that the pressure contact amount changes according to the unevenness of the object S. For example, when the depth of the recess S1 of the object S is 1 mm or less, if the pressure contact amount is adjusted to be 0.3 mm at the deepest part of the recess S1, the pressure contact amount on the surface of the object S (other than the recess S1) does not exceed 1.3 mm. Therefore, depending on the depth of the recess S1, even if the first cleaning brush 10 and the second cleaning brush 20 are fixed, it is possible to control the pressure contact amount to be a desired value.

[0094] When the cleaning method uses the cleaning device 1 of the present invention and controls the pressing amount of the first cleaning brush 10 and the second cleaning brush 20 at the contact portion with the object S to be 0.2 mm or more and 1.5 mm or less, the foreign matter X can be efficiently scraped out from the recess S1 while suppressing the scattering of the foreign matter X.

[0095] [Other Embodiments] The present invention is not limited to the above-described embodiments, and can be implemented in various modified and improved forms in addition to the above aspects.

[0096] In the above embodiment, the case where the cleaning device removes the foreign matter adhering to one surface of the object has been described. However, the cleaning device may be configured to remove the foreign matter adhering to both surfaces of the object, that is, in addition to the above one surface, the foreign matter adhering to the other surface. In this case, for removing the foreign matter adhering to the other surface, the first cleaning brush, the second cleaning brush, and the cleaning roller may be used in the same manner as for removing the foreign matter on the above one surface, but it is preferable to remove the foreign matter only with the second cleaning brush and the cleaning roller. In this case, it is preferable to perform cleaning so that the above one surface of the object becomes the upper surface. That is, the unit composed of the first cleaning brush, the second cleaning brush, and the cleaning roller is configured to remove the foreign matter on the upper surface side of the object, and the unit composed of only the second cleaning brush and the cleaning roller is configured to remove the foreign matter on the lower surface side of the object.

[0097] In the above embodiment, in the cleaning method, the case where the pressing amounts of the first cleaning brush and the second cleaning brush are controlled to be within a certain range regardless of the location has been described. However, when the shape of the recess is cylindrical or prismatic composed of a bottom surface and a side surface, only the pressing amounts of the first cleaning brush and the second cleaning brush on the bottom surface may be controlled. Even if only the bottom surface of the recess is controlled in this way, a certain effect can be obtained. In particular, when a plurality of recesses of the object have the same shape, the pressing amount can be set to a fixed value, so that complicated control is not required.

[0098] In the above embodiment, the case where the cleaning device includes a guide roller has been described. However, when the object is, for example, a plate-like object that is difficult to bend at the tip and it is easy for the tip to enter between the cleaning brush and the second counter electrode roller, the guide roller may be omitted.

[0099] Moreover, the transport mechanism is not limited to the above-described configuration. Any configuration can be adopted as long as it can transport the object.

Industrial Applicability

[0100] As described above, the cleaning device of the present invention can effectively remove foreign matter even from an object having recesses on its surface. Also, by using the cleaning method of the present invention, foreign matter can be effectively removed even from an object having recesses on its surface.

Explanation of Signs

[0101] 1 Cleaning device 1a First brush unit 1b Second brush unit 1c Roller unit 10 First cleaning brush 11 Shaft core 12 Brush part 13 First dust collecting roller 14 First scraper 15 First foreign matter recovery part 16 First counter electrode roller 20 Second cleaning brush 21 Shaft core 22 Brush part 23 Second dust collecting roller 24 Second scraper 25 Second foreign matter recovery part 26 Second counter electrode roller 30 Cleaning roller 31 Shaft core 32 Inner layer part 33 Outer layer part 34 Brush roller 35 Third dust roller 36 Third scraper 37 Third foreign object collection part 38 Third counter electrode roller 38a Mandrel 38b Insulating layer 40 Guide roller 50 Conveying mechanism 50a Upstream conveying mechanism 50b Downstream conveying mechanism 51 Belt conveying part 52 Conveying roller 53 Endless belt S Object S1 Recess S1a Bottom surface S1b Side surface D Conveying direction X Foreign object

Claims

1. A cleaning device for removing foreign matter adhering to at least one surface of a plate-like or film-like object, comprising: a roller-shaped first cleaning brush that is rotatably disposed about a rotation axis that is perpendicular to a conveying direction of the object and parallel to the one surface and that contacts the one surface; a roller-shaped second cleaning brush located downstream of the first cleaning brush, the rotation axis of which is arranged parallel to that of the first cleaning brush, and which rotates while contacting the one surface; a cleaning roller located downstream of the second cleaning brush, the rotation axis of which is arranged parallel to that of the second cleaning brush, and which rotates while coming into contact with the one surface; Equipped with a rotation direction of the first cleaning brush and the cleaning roller at a contact portion with the one surface is a forward direction with respect to the conveying direction, a cleaning device in which the second cleaning brush rotates in a direction opposite to the conveying direction at a contact portion with the one surface;

2. 2. The cleaning device according to claim 1, wherein a ratio of a peripheral speed of the first cleaning brush to a transport speed of the object at a contact portion with the one surface is 1.3 times or more and 3.0 times or less.

3. 3. The cleaning device according to claim 1, wherein a ratio of a peripheral speed of the second cleaning brush to a transport speed of the object at a contact portion with the one surface is 0.1 to 0.5 times.

4. 2. The cleaning device according to claim 1, wherein the first cleaning brush, the second cleaning brush and the cleaning roller contact the one surface in a charged state.

5. 2. The cleaning device according to claim 1, wherein the object has a recess in the one surface.

6. A cleaning method for removing foreign matter adhering to at least one surface of a plate-like or film-like object, comprising the steps of: Using the cleaning device according to claim 1, the first cleaning brush and the second cleaning brush each have a cylindrical core and a brush portion formed by planting a plurality of bristles on a circumferential surface of the core, a cleaning method in which the amount of pressure contact of the first cleaning brush and the second cleaning brush at the contact portion with the object is controlled to be 0.2 mm or more and 1.5 mm or less.

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