WO2009096626A1

WO2009096626A1 - Apparatus for removing inferiority of rubbing cloth

Info

Publication number: WO2009096626A1
Application number: PCT/KR2008/001380
Authority: WO
Inventors: Jong-Bok Lee
Original assignee: Nexcomm Global Co., Ltd.
Priority date: 2008-01-30
Filing date: 2008-03-12
Publication date: 2009-08-06
Also published as: JP2010507837A; KR100940917B1; TW200933139A; CN101622573B; JP5007346B2; TWI372243B; KR20090083768A; CN101622573A

Abstract

An apparatus for removing inferiority rubbing cloth incldudes a base, a rubbing roller supported by support members mounted at opposite ends of the base, the rubbing roller being rotatable by a drive motor, an image acquisition unit movable horizontally by a linear motor, the image acquisition unit being provided at the front thereof with cameras for three-dimensionally photographing the rubbing roller, a central control unit for calculating the distance between opposite ends of the rubbing cloth in real time through the use of three-dimensional images, analyzing and outputting and storing the calculated values, and a removing unit mounted at the top of the base, such that the removing unit is movable horizontally, for removing lint or foreign matter and a strand protruding, the removing unit being disposed perpendicular to the rubbing roller and being controlled by the central control unit.

Description

APPARATUS FOR REMOVING INFERIORITY OF RUBBING

CLOTH

Technical Field

[1] The present invention relates to an apparatus for removing badness or defectiveness of rubbing cloth that is capable of inspecting a rubbing roller for orientation-processing an orientation film of a liquid crystal display panel to automatically remove foreign matter from rubbing cloth of the rubbing roller. Background Art

[2] Generally, an orientation process is carried out on a liquid crystal display panel to arrange liquid crystal molecules of the liquid crystal display panel.

[3] As an orientation-processing method, there is being used a method of rubbing the surface of an orientation film of a liquid crystal display panel using rubbing cloth of a rubbing apparatus constructed in a structure in which the rubbing cloth is wound on a rotary rubbing roller.

[4] Specifically, the rubbing apparatus is constructed in a structure in which the rubbing cloth is attached to the outer circumference of the rubbing roller, normally made of aluminum or stainless steel. Upon rotating the rubbing roller, the rubbing cloth rubs the surface of the orientation film of the liquid crystal display panel while the rubbing cloth is in contact with the surface of the orientation film. Liquid crystal molecules are arranged in the rubbing direction, and therefore, the orientation film of the liquid crystal display panel has uniform characteristics.

[5] As the rubbing cloth used in the rubbing apparatus, there is generally used velvet obtained by raising texture and fibers. After the rubbing cloth is used for a long time, lint may be raised from the rubbing cloth, the rubbing cloth may be distorted due to the elasticity of the rubbing cloth itself, or foreign matter may stick on the rubbing cloth. The surface of the liquid crystal display panel, oriented by the rubbing cloth, may be scratched due to such badness or defectiveness of the rubbing cloth, with the result that the liquid crystal display panel may be defective.

[6] In order to solve the above-mentioned problem, the rubbing cloth may be inspected from time to time. However, this inspection method is no more than inspection with the naked eye. As a result, it is not possible to detect micro defectiveness of the rubbing cloth, whereby the defect ratio of liquid crystal display panels increases.

[7] To solve this problem, there has been developed an apparatus for automatically detecting badness or defectiveness of rubbing cloth in recent years. However, this apparatus also has a problem in that the bad or defective rubbing cloth is removed manually by a person. [8]

Disclosure of Invention Technical Problem

[9] Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide an apparatus for removing badness or defectiveness of rubbing cloth that is capable of automatically detecting a strand protruding from the rubbing cloth, caused by lint raised on the rubbing cloth, and automatically removing the protruding strand from the rubbing cloth. Technical Solution

[10] In accordance with the present invention, the above and other objects can be accomplished by the provision of an apparatus for removing badness or defectiveness of rubbing cloth including a base, a rubbing roller supported by support members mounted at opposite ends of the base, the rubbing roller being rotatable by a drive motor mounted at the outside of one of the support members, an image acquisition unit movable horizontally by a linear motor mounted at one side of the top of the base, the image acquisition unit being provided at the front thereof with pluralities of cameras for three-dimensionally photographing the rubbing roller, a central control unit for calculating the eccentricity at opposite sides of the rubbing roller and the distance between opposite ends of the rubbing cloth wound on the rubbing roller in real time through the use of three-dimensional images photographed by the image acquisition unit, analyzing and outputting the calculated values, and storing the calculated values in a database, and a removing unit mounted at the top of the base, such that the removing unit is movable horizontally, for removing lint or foreign matter on the rubbing cloth and a strand protruding from the rubbing cloth, acquired by the image acquisition unit, the removing unit being disposed perpendicular to the rubbing roller and being controlled by the central control unit. Brief Description of the Drawings

[11] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[12] FIG. 1 is a plan view illustrating an apparatus for removing badness or defectiveness of rubbing cloth according to the present invention;

[13] FIG. 2 is a block diagram illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention;

[14] FIG. 3 is a plan view illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention with a backlight of FIG. 1 removed; [15] FIG. 4 is a plan view illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention with a rubbing roller of FIG. 2 removed;

[16] FIG. 5 is a plan view illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention with an image acquisition unit of FIG. 4 moving horizontally;

[17] FIG. 6 is a plan view illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention with a removing unit of FIG. 4 moving horizontally;

[18] FIG. 7 is a side view of FIG. 1 ;

[19] FIG. 8 is a view illustrating the operation of first cameras of FIG. 7;

[20] FIG. 9 is a view illustrating the operation of second cameras and third cameras of

FIG. 7;

[21] FIG. 10 is a side view illustrating the position of a second embodiment of the third cameras;

[22] FIG. 11 is a side view illustrating the position of a third embodiment of the third cameras;

[23] FIG. 12 is a conceptional view illustrating a first operation of the removing unit; and

[24] FIG. 13 is a conceptional view illustrating a second operation of the removing unit.

Best Mode for Carrying Out the Invention

[25] Now, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[26] FIG. 1 is a plan view illustrating an apparatus for removing badness or defectiveness of rubbing cloth according to the present invention, FIG.2 is a block diagram illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention, FIG. 3 is a plan view illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention with a backlight of FIG. 1 removed, FIG. 4 is a plan view illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention with a rubbing roller of FIG. 2 removed, FIG. 5 is a plan view illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention with an image acquisition unit of FIG. 4 moving horizontally, and FIG. 6 is a plan view illustrating the apparatus for removing badness or defectiveness of rubbing cloth according to the present invention with a removing unit of FIG. 4 moving horizontally.

[27] As shown in FIGS. 1 to 6, the present invention relates to an apparatus for removing badness or defectiveness of rubbing cloth that is capable of inspecting a rubbing roller for orientation-processing an orientation film of a liquid crystal display panel to automatically remove foreign matter from rubbing cloth of the rubbing roller. More particularly, the present invention relates to a rubbing cloth badness or defectiveness removing apparatus 100 that is capable of rotating a rubbing roller to inspect the deformation of rubbing cloth wound on the rubbing roller or the contamination degree of the rubbing cloth to determine whether the rubbing cloth is defective or not, and, when lint is raised on the rubbing cloth and thus a strand protrudes from the rubbing cloth, determining the position of the protruding rubbing cloth strand to automatically remove the protruding strand from the rubbing cloth.

[28] The rubbing cloth badness or defectiveness removing apparatus 100 largely includes four units. Specifically, the rubbing cloth badness or defectiveness removing apparatus 100 includes a rubbing roller 20, an image acquisition unit 30 for acquiring the image of rubbing cloth 21 wound on the rubbing roller 20, a central control unit 50 for determining whether the rubbing cloth 21 wound on the rubbing roller 20 is defective or not based on the acquired image of the rubbing cloth 21, and a removing unit 40 for removing a rubbing cloth strand 22 protruding from the rubbing cloth 21.

[29] The rubbing roller 20 is constructed in a structure in which the rubbing roller 20 is supported by support members 11 mounted at opposite ends of a base 10, and the rubbing roller 20 is rotated by a drive motor 12 mounted at the outside of one of the support members 11.

[30] The image acquisition unit 30 is constructed in a structure in which the image acquisition unit 30 is movable horizontally by a linear motor 31 mounted at one side of the top of the base 10, and pluralities of cameras 321, 322, and 323 for acquiring a three-dimensional image of the rubbing roller 20 are mounted at the front of the image acquisition unit 30.

[31] Specifically, the image acquisition unit 30 includes a transfer plate 32 movable horizontally by the linear motor 31, a plurality of first cameras 321 mounted horizontally at the front of the transfer plate 32 for photographing the center of the rubbing roller 20 to measure the distance between opposite ends of the rubbing cloth 21 wound on the rubbing roller 20, first light emitting devices 324 mounted on the first cameras 321 for emitting light to the rubbing roller 20, and a plurality of second cameras 322 and a plurality of third cameras 323 mounted horizontally at the front of the transfer plate 32 for three-dimensionally photographing lint or foreign matter on the rubbing cloth 21 and a strand 22 protruding from the rubbing cloth 21, respectively.

[32] Preferably, at least two first cameras 321 are arranged horizontally to simultaneously photograph a predetermined range of the surface of the rubbing roller 20. The first cameras 321 mainly photograph the center of the rubbing roller 20. Specifically, the first cameras 321 photograph the distance between the opposite ends of the rubbing cloth 21 to measure the distance between the opposite ends of the rubbing cloth 21, and, in addition, photographs lint on the rubbing cloth 21 to measure the lint on the rubbing cloth 21.

[33] The second cameras 322 are mounted below the respective first cameras 321 for photographing the outer circumference of the rubbing cloth 21, and the third cameras 323 are mounted below the respective second cameras 322 for photographing the bottom of the rubbing cloth 21. Here, the second cameras 322 and the third cameras 323 are mounted tangential to the rubbing cloth 21.

[34] Consequently, the second cameras 322 and the third cameras 323 three-di- mensionally photograph the strand 22 protruding from the rubbing cloth 21, and the central control unit 50 determines the position of the protruding strand 21 based on a three-dimensional image acquired by three-dimensionally photographing the protruding strand 21 using the second cameras 322 and the third cameras 323.

[35] Also, the first light emitting devices 324 serve to emit light to the rubbing roller 20.

The first light emitting devices 324 are mounted coaxially on the respective first cameras 321. To this end, each first light emitting device 324 is formed in the shape of a ring having a space defined therein. With this structure, it is possible to acquire a clearer image during the photographing process.

[36] Meanwhile, the central control unit 50 calculates the distance between the opposite ends of the rubbing cloth 21 wound on the rubbing roller 20 in real time, using three- dimensional images photographed by the image acquisition unit 30, analyzes and output the calculated values, stores the calculated values in a database (not shown), and controls the removing unit 40 based on the stored values.

[37] At this time, the three-dimensional images photographed by the image acquisition unit 30 may be displayed through a display unit 60 such that a person can monitor the three-dimensional images.

[38] Also, it is obvious that the drive time of the image acquisition unit 30, i.e., a reference value for adjusting photographing cycles and distinguishing between goodness and badness or defectiveness, is inputted to the database of the central control unit 50, and, in addition, the database of the central control unit 50 has a program for comparing the photographed images with the inputted reference value and a program for controlling the removing unit 40 to be moved to a bad point region of t he photographed image.

[39] The removing unit 40 is constructed in a structure in which the removing unit 40 is mounted at the top of the base, such that the removing unit 40 is movable horizontally, to remove the lint or foreign matter on the rubbing cloth 21 and the strand 22 protruding from the rubbing cloth 21, acquired by the image acquisition unit 30. The removing unit 40 is disposed perpendicular to the rubbing roller 20 and is controlled by the central control unit 50.

[40] The removing unit 40 includes a moving plate 45 mounted on a second linear motor

44 mounted at the top of the base 10 such that the moving plate 45 is movable horizontally, a lifting member mounted at the top of the moving plate 45, and clampers 41 mounted at the top of the lifting member.

[41] The clampers 41 may be driven in a pneumatic fashion, in a motor-based fashion, or in a hydraulic fashion. Between the clampers 41 is formed a suction hole 411 for suctioning the rubbing cloth strand 22 separated from the rubbing cloth 21. At the bottom of the clampers 41 are mounted a rotation part 43 for rotating the clampers 41 when the strand 22 protruding from the rubbing cloth 21 becomes curved.

[42] The lifting member for lifting the clampers 41 may be realized by a servo motor, a cylinder 42, or a linear motor. In this embodiment, the lifting member for lifting the clampers 41 is realized by the cylinder 42.

[43] Meanwhile, a second light emitting device 70, which is a backlight for emitting light to the rubbing roller 20, is further mounted at the other side of the base 10 in the longitudinal direction. When the lower end of the rubbing cloth 21 is photographed using the second light emitting device 70, the edge of the rubbing cloth 21 is more highlighted, whereby it is possible to acquire a clearer image.

[44] FIG. 7 is a side view of FIG. 1, and FIG. 8 is a view illustrating the operation of the first cameras of FIG. 7.

[45] During the rotation of the rubbing roller 20, as shown in FIGS. 7 and 8, the at least two first cameras 321, mounted horizontally, simultaneously photograph a predetermined range of the surface of the rubbing roller 20. As previously described, the first cameras 321 mainly photograph the center of the rubbing roller 20. The first cameras 321 photograph the distance between opposite ends of the rubbing cloth 21 wound on the rubbing roller 20 to measure the distance between opposite ends of the rubbing cloth 21 wound on the rubbing roller 20, and, in addition, photograph the lint 23 on the rubbing cloth 21 to measure the lint 23 on the rubbing cloth 21.

[46] Here, the first cameras 321 may be constructed such that, when the distance between the opposite ends of the rubbing cloth 21 and the lint 23 on the rubbing cloth 21 exceed an error range, badness or defectiveness of the rubbing cloth 21 is determined, and the badness or defectiveness of the rubbing cloth 21 is recognized by a warning device (not shown), such as an alarm.

[47] FIG. 9 is a view illustrating the operation of the second cameras and the third cameras of FIG. 7.

[48] During the rotation of the rubbing roller 20, as shown in FIG. 9, the second cameras

322, mounted below the respective first cameras 321, photograph the outer circumference of the rubbing cloth 21, and the third cameras 323, mounted below the second cameras 322, photograph the bottom of the rubbing cloth 21. The second cameras 322 and the third cameras 323 are mounted tangential to the rubbing cloth 21.

[49] Here, the second cameras 322 may be constructed such that, when the lint 23 is raised on the outer circumference of the rubbing cloth 21, photographed by the second cameras 322, and therefore, the corresponding region of the outer circumference of the rubbing cloth 21 protrudes to the extent that the protruding region exceeds an error range, badness or defectiveness of the rubbing cloth 21 is determined, and the badness or defectiveness of the rubbing cloth 21 is recognized by a warning device (not shown), such as an alarm.

[50] Also, the third cameras 323 three-dimensionally photograph the strand 22 protruding from the rubbing cloth 21 together with the second cameras 322, and the central control unit 50 determines the position of the protruding strand 22 according to the two three-dimensional images acquired by the second cameras 322 and the third cameras 323.

[51] That is, when the strand 22 protruding from the rubbing cloth 21 is curved or lies down, the position of the protruding strand 22 is correctly determined through the third cameras 323.

[52] FIG. 10 is a side view illustrating the position of a second embodiment of the third cameras, and FIG. 11 is a side view illustrating the position of a third embodiment of the third cameras.

[53] Referring first to FIG. 10, the third cameras 323 according to the second embodiment are mounted in the base 10, such that lenses of the third cameras 323 are exposed from the top of the base 10 at the positions perpendicular to the rubbing roller 20, to precisely three-dimensionally photograph the strand 22 protruding from the rubbing cloth 21 together with the second cameras 322.

[54] Referring to FIG. 11, the third cameras 323 according to the third embodiment are mounted at the other side of the top of the base 10 such that the third cameras 323 are disposed tangential to the rubbing cloth 21.

[55] FIG. 12 is a conceptional view illustrating a first operation of the removing unit.

[56] First, it is required for the removing unit 40 to be moved to a corresponding position according to a positional value calculated by comparison between the images acquired by the second cameras 322 and the third cameras 323, which is carried out by the central control unit 50, before the operation of the removing unit 40.

[57] Subsequently, as shown in FIG. 12, the cylinder 42 is raised under the control of the central control unit 50, and therefore, the clampers 41 approach the strand 22 protruding from the rubbing cloth 21.

[58] The clampers 41 clamp the strand 22 protruding from the rubbing cloth 21. After the completion of the clamping process, the cylinder 42 is lowered to separate the protruding strand 22 from the rubbing cloth 21.

[59] Simultaneously when the clamping process of the clampers 41 is released, the protruding strand 22, separated from the rubbing cloth 21, is suctioned into the suction hole 411, whereby the protruding strand 22 is completely removed.

[60] FIG. 13 is a conceptional view illustrating a second operation of the removing unit.

[61] The second operation of the removing unit is carried out when the strand protruding from the rubbing cloth lies down.

[62] In this case, it is required to suction air through the suction hole 411 to erect the strand lying down on the rubbing cloth before raising the cylinder 42 to move the clampers upward such that the strand 22 protruding from the rubbing cloth 21 is clamped by the clampers 41. Subsequently, the strand 22 protruding from the rubbing cloth 21 is removed in the same way as in FIG. 12.

[63] In the above description, the removing member of the rubbing cloth badness or de- fectiveness removing apparatus according to the present invention is realized by the clampers. However, the present invention is not limited thereto. For example, it is possible to remove the strand 22 protruding from the rubbing cloth 21 using laser. Industrial Applicability

[64] As apparent from the above description, the rubbing cloth badness or defectiveness removing apparatus according to the present invention is capable of rotating the rubbing roller to inspect the deformation of the rubbing cloth wound on the rubbing roller or the contamination degree of the rubbing cloth to determine whether the rubbing cloth is defective or not, and, when the lint is raised on the rubbing cloth and thus the strand protrudes from the rubbing cloth, determining the position of the protruding rubbing cloth strand to automatically remove the protruding strand from the rubbing cloth. Consequently, the present invention has the effect of preventing the badness or defectiveness of a liquid crystal display panel caused by the badness or defectiveness of the rubbing roller or the rubbing cloth.

[65] Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

[1] An apparatus for removing badness or defectiveness of rubbing cloth that is used to inspect a rubbing roller for orientation-processing an orientation film of a liquid crystal display panel and automatically remove foreign matter from rubbing cloth of the rubbing roller, the apparatus comprising: a base; a rubbing roller supported by support members mounted at opposite ends of the base, the rubbing roller being rotatable by a drive motor mounted at the outside of one of the support members; an image acquisition unit movable horizontally by a linear motor mounted atone side of the top of the base, the image acquisition unit being provided at the front thereof with pluralities of cameras for three-dimensionally photographing the rubbing roller; a central control unit for calculating the eccentricity at opposite sides of the rubbing roller and the distance between opposite ends of the rubbing cloth wound on the rubbing roller in real time through the use of three-dimensional images photographed by the image acquisition unit, analyzing and outputting the calculated values, and storing the calculated values in a database; and a removing unit mounted at the top of the base, such that the removing unit is movable horizontally, for removing lint or foreign matter on the rubbing cloth and a strand protruding from the rubbing cloth, acquired by the image acquisition unit, the removing unit being disposed perpendicular to the rubbing roller and being controlled by the central control unit.

[2] The apparatus according to claim 1, wherein the image acquisition unit includes a transfer plate movable horizontally by the linear motor; a plurality of first cameras mounted horizontally at the front of the transfer plate for photographing the center of the rubbing roller to measure the distance between the opposite ends of the rubbing cloth wound on the rubbing roller; first light emitting devices mounted coaxially on the first cameras for emitting light to the rubbing roller; and a plurality of second cameras and a plurality of third cameras mounted horizontally at the front of the transfer plate for three-dimensionally photographing the lint or the foreign matter on the rubbing cloth and the strand protruding from the rubbing cloth, respectively.

[3] The apparatus according to claim 2, wherein the second cameras are mounted below the first camera for photographing the outer circumference of the rubbing cloth, and the third cameras are mounted below the second camera for photographing the bottom of the rubbing cloth, the third cameras being disposed tangential to the rubbing cloth.

[4] The apparatus according to claim 3, wherein the third cameras are mounted in the base such that lenses of the third cameras are exposed from the top of the base at the positions perpendicular to the rubbing roller.

[5] The apparatus according to claim 3, whereinthe third cameras are mounted at the other side of the top of the base, such that the third cameras are disposed tangential to the rubbing cloth, for photographing the bottom of the rubbing cloth.

[6] The apparatus according to claim 1, wherein the removing unit includes a moving plate mounted on a second linear motor mounted at the top of the base such that the moving plate is movable horizontally, a lifting member mounted at the top of the moving plate, and clampers mounted at the top of the lifting member.

[7] The apparatus according to claim 6, wherein the removing unit further includes a suction hole formed between the clampers for suctioning the rubbing cloth strand separated from the rubbing cloth.

[8] The apparatus according to claim 7, wherein the removing unit further includes a rotation part mounted at the bottom of the clampers for rotating the clampers.

[9] The apparatus according to claim 1, further comprising: a second light emitting device mounted at the other side of the base in the longitudinal direction for emitting light to the rubbing roller.