Abstract:
A film laminating apparatus and method for a plate member having a flat or curved surface includes a first holder, a pressing roll, a film holder, support means, position confirmation means and alignment means. The first holder has absorption means that allows a plate member to be absorbed to a surface thereof by deforming the plate member. The pressing roll presses a film on a surface of the plate member absorbed to the first holder. The film holder is provided to the pressing roll, and fixes the film to be laminated to a surface of the pressing roll. The support means supports the pressing roll to be movable. The position confirmation means confirms the position of the plate member and the position of the film fixed to the pressing roll. The alignment means aligns the film and the plate member, based on the positions confirmed by the position confirmation means.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    Pursuant to 35 U.S.C. §119(a), this application claims the benefit of earlier filing date and right of priority to Korean Applications Nos. 10-2012-0001126 and 10-2012-0001129, filed on Jan. 4, 2012, the contents of which is incorporated by reference herein in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present disclosure relates to a film laminating apparatus and method for a flat or curved plate member, and particularly, to an apparatus and method for is laminating a film having a predetermined pattern or texture on a surface of a plate member having an arbitrary shape. 
         [0004]    2. Description of the Conventional Art 
         [0005]    A cabinet forming the external shape of a home appliance such as a washing machine or refrigerator is processed to have a predetermined shape by performing a machining process such as pressing or deep drawing on a panel made of carbon steel, stainless steel, etc. 
         [0006]    Various colors may be applied to the cabinet so that the cabinet has a beautiful exterior appearance. The cabinet may entirely have one color or may have a color of two or more tones so as to look more luxurious. A method of coating pigments with two colors on the surface of a metal panel may be considered so that the surface of the metal panel has various colors. However, the method is not used for luxury products due to low durability and poor quality of exterior appearance. 
         [0007]    A method of laminating a film having a specific pattern or metallic texture on the surface of a panel may be used as another method. The method can provide the panel with a texture similar to that of an actual metal material, but has a problem in that its application range is limited. That is, in case of a home appliance, a panel has not only an irregular surface such as a protruding portion or concave portion but also various shape including a flat surface, a curved surface, etc. Therefore, it is not easy to uniformly laminate a film on the panel having an arbitrary shape. 
         [0008]    That is, as shown in  FIG. 1 , a conventional film laminating apparatus  10  is configured by receiving a film supplied from a film supply roll  12  for supplying the is film to be laminated, laminating the film on a surface of a plate member using a pair of pressing rolls  14  and then cutting the film to a predetermined size using a cutter. A protective film laminated on the rear of the film is wound around a winding roll  18  after the film is delaminated from the protective film. 
         [0009]    The plate member is washed by sequentially passing through a water supply nozzle  20 , a brush  22 , a moisture removal device  24  and a dryer  26 , and then transferred to the pressing roll  14  by a roller  30 . 
         [0010]    The film laminating apparatus continuously laminates the film on the plate member, so that it is possible to uniformly maintain quality and to improve productivity. However, the film laminating apparatus is limited to the case where the member on which the film is to be laminated is a plate member. 
         [0011]    Therefore, the film should be manually laminated on a panel having a curved surface or protruding portion. In this case, it is highly likely that a variation in quality may occur, and the productivity is not high. 
       SUMMARY OF THE INVENTION 
       [0012]    Therefore, an aspect of the detailed description is to provide a film laminating apparatus capable of easily laminating a film even on a panel having a protruding portion or curved surface. 
         [0013]    Another aspect of the detailed description is to provide a film laminating method capable of easily laminating a film even on a panel having a protruding portion or curved surface. 
         [0014]    To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, a film laminating apparatus includes a first holder having an absorption means that allows a plate member to be absorbed to a surface thereof by deforming the plate member; a pressing roll pressing a film on a surface of the plate member absorbed to the first holder; a film holder provided to the pressing roll, and fixing the film to be laminated to a surface of the pressing roll; a support means supporting the pressing roll to be movable; a position confirmation means confirming the position of the plate member and the position of the film fixed to the pressing roll; and an alignment means aligning the film and the plate member, based on the positions confirmed by the position confirmation means. 
         [0015]    When the film is laminated on the plate member having a curved surface, the plate member is deformed and absorbed on the surface of the first holder through the absorption means provided to the first holder, so that the lamination of the film using the pressing roll is possible. Accordingly, the film can be automatically laminated on plate members having various shapes, so that it is possible to obtain panels having uniform quality and to improve productivity. 
         [0016]    The absorption means may include a plurality of absorption holes formed in an upper surface of the first holder; and a vacuum pump forming negative pressure in the absorption holes. In addition, the film holder provided to the pressing roll may have the same configuration. 
         [0017]    The support means may be configured to move the pressing roll along a lamination direction of the film on the plate member. The support means may include a rail extended in the length direction of the first holder; a slider mounted to move along the rail, and having the pressing roll rotatably mounted therebeneath; a driving motor rotating the pressing roll; and an ascending/descending means ascending/descending the rail in the vertical direction. 
         [0018]    The support means may support the pressing roll to be vertically movable, and the first holder may be mounted to be movable along the lamination direction of the film. 
         [0019]    The film may be previously trimmed in a predetermined shape and then supplied to the surface of the pressing roll. The film may be supplied in a state in which the film is wound around a film supply roll and then cut away by a cutter cutting the film after being laminated on the surface of the plate member by the pressing roll. 
         [0020]    The film holder may further include a metal net stacked on the surface of the pressing roll. Accordingly, it is possible to minimize the deformation of the surface of the plate member due to the absorption holes provided to the film holder. The metal net may be made of stainless steel. 
         [0021]    A concave portion recessed inward from the circumferential surface of the pressing roll may be provided to the pressing roll. In a case where a protruding portion is formed on the surface of the plate member, the concave portion allows the protruding portion to be received by the concave portion in the process of laminating the film, so that the film can be laminated up to the surroundings of the protruding portion by the pressing roll. 
         [0022]    The concave portion may include a first cut-away surface extended toward the center of the pressing roll; and a second cut-away surface extended toward the circumference of the pressing roll from the first cut-away surface. Accordingly, the film can be laminated using the pressing roll even when the surface of the plate member is bent to be vertical or inclined. 
         [0023]    To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, a film laminating apparatus includes a first holder having an absorption means that allows a plate member to be absorbed to a surface thereof by deforming the plate member; a second holder having a second absorption means that allows a film cut away in a predetermined shape to be absorbed on a surface thereof; a pressing roll attaching the absorbed film on the surface of the second holder and then pressing the film on the surface of the plate member absorbed to the first holder; a support means supporting the pressing roll to be movable between the first and second holders; a position confirmation means confirming the position of the plate member and the position of the film fixed to the pressing roll; and an alignment means aligning the film and the plate member, based on the positions confirmed by the position confirmation means. 
         [0024]    Accordingly, the film can be stably laminated on the surface of the plate member by the pressing roll even when the film to be laminated does not have a rectangular shape but has an arbitrary shape. 
         [0025]    The support means may include a rail extended between the first and second holders; a slider mounted to move along the rail, and having the pressing roll rotatably mounted therebeneath; a driving motor rotating the pressing roll; and an ascending/descending means ascending/descending the rail in the vertical direction. 
         [0026]    The film may be previously trimmed in a predetermined shape and then supplied to the second holder. 
         [0027]    To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, a film laminating method includes fixing a plate member in a deformed state to a first holding surface so that the first holding surface and a surface of the plate member contact each other; fixing a film to a surface of a pressing roll; pressing the pressing roll having the film fixed thereto on the surface of the plate member; and restoring the plate member to have the initial shape. 
         [0028]    Accordingly, the automated film lamination can be performed on even the plate member having a curved surface rather than a flat surface by pressing the film in a state in which the plate member is deformed and fixed to the first holding surface and restoring the plate member to have the original shape. The plate member may have a plate shape in which the entire plate member is adhered closely to the first holding surface, or only a partial surface of the plate member may be deformed and fixed to the first holding surface. That is, the deformed surface may be limited to a region on which the film is attached. 
         [0029]    The plate member may be deformed using various methods. For example, the plate member may be deformed by pressing the other region of the plate member except the region on which the film is attached, using a separate frame, or may be deformed using a vacuum absorption method. That is, the deforming the plate member may include deforming the plate member toward the holding surface by applying absorption pressure in the state in which the plate member is holed on the first holding surface. In this case, the restoring of the plate member may include removing the absorption pressure applied to the rear surface of the plate member having the film laminated thereon. 
         [0030]    The fixing of the film to the surface of the pressing roll may include cutting away the film in a predetermined shape; and absorbing the cut film to the surface of the pressing roll. 
         [0031]    The shape of the cut film may be determined, based on the state in which the plate member is deformed. That is, the film is not laminated on the plate member having the curved surface but laminated on the plate member deformed in a plate shape. Thus, if the shape of the cut film is determined in consideration of the deformation of the plate member in the cutting of the film to be laminated, the film can be more precisely laminated on the plate member. 
         [0032]    The fixing of the film to the surface of the pressing roll may include fixing the cut film to a second holding surface; aligning the pressing roll with respect to the film; and transferring the film to the surface of the pressing roll by applying absorption pressure in a state in which the pressing roll contacts an upper surface of the film. 
         [0033]    In the pressing of the film on the surface of the plate member, the absorption pressure between the film and the pressing roll may be set to be smaller than the adhesion between the film and the plate member. 
         [0034]    To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, a film laminating method includes fixing a plate member in a deformed state to a first holding surface so that the first holding surface and a surface of the plate member contact each other; transferring, toward a pressing roll, the first holding surface having the plate member fixed thereto; supplying a film between the pressing roll and the plate member; pressing the supplied film on the surface of the plate member using the pressing roll; cutting away the film pressed on the plate member; and restoring the plate member to have the initial shape. 
         [0035]    Accordingly, in a case where the shape of the film to be laminated is simple, the film is not cut away in advance, but cut away after the film is laminated on the plate member, thereby more quickly supplying the film. 
         [0036]    The film may be supplied from a film supply roll around which a raw film is wound. 
         [0037]    According to the exemplary embodiments configured as described above, the plate member having a curved surface is deformed to have a flat surface and then absorbed on the surface of the first holder, so that the lamination of the film using the pressing roll is possible. Accordingly, the film can be automatically laminated on plate members having various shapes, so that it is possible to obtain panels having uniform quality and to improve productivity. 
         [0038]    Further, a separate holder for absorbing the film is provided, and the film absorbed to the holder is absorbed to the surface of the pressing roll, so that the film having various shapes can be automatically laminated on the plate member. 
         [0039]    Further scope of applicability of the present application will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from the detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0040]    The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments and together with the description serve to explain the principles of the invention. 
           [0041]    In the drawings: 
           [0042]      FIG. 1  is a perspective view schematically illustrating a conventional film laminating apparatus; 
           [0043]      FIG. 2  is a side view schematically illustrating a film laminating apparatus according to an exemplary embodiment; 
           [0044]      FIG. 3  is a perspective view illustrating a pressing roll in the film laminating apparatus shown in  FIG. 2 ; 
           [0045]      FIG. 4  is a side view illustrating a process of absorbing a film in the film laminating apparatus shown in  FIG. 2 ; 
           [0046]      FIG. 5  is a side view illustrating a process of laminating the film in the film laminating apparatus shown in  FIG. 2 ; 
           [0047]      FIG. 6  is a side view schematically illustrating a trimming device provided the film laminating apparatus shown in  FIG. 2 ; and 
           [0048]      FIG. 7  is a flowchart illustrating a film laminating method using the film laminating apparatus according to an exemplary embodiment. 
       
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       [0049]    Hereinafter, a film laminating apparatus according to an exemplary embodiment will be described in detail with reference to the accompanying drawings. 
         [0050]      FIG. 2  is a side view schematically illustrating a film laminating apparatus according to an exemplary embodiment. Referring to  FIG. 2 , the film laminating apparatus  100  according to the exemplary embodiment includes a first holder  110  absorbing and holding a plate member  50 , and a second holder  120  absorbing and holding a film  60  to be laminated on the plate member  50 . 
         [0051]    A plurality of absorption holes  112  are formed in the holding surface  111  of the first holder  110 , and a vacuum pump (not shown) forming negative pressure in the absorption holes  112  is further provided to the first holder  110 . If the vacuum pump is operated, the negative pressure is formed in the absorption holes  112  so as to absorb the plate member  50 . Here, the plate member  50  is formed to have a curved surface as indicated by a dotted line. However, the plate member  50  having the curved surface is absorbed to the holding surface  111  due to the negative pressure of the absorption holes  112  so as to be deformed in the shape of a flat plate. Absorption pressure does not reach a vertical bending portion  51  formed at one end portion of the plate member  50 , and therefore, the vertical bending portion  51  is disposed perpendicular to the holding surface  111  as shown in this figure. 
         [0052]    The first holder  110  is disposed to be movable in front, rear, left and right directions with respect to the ground and to be rotatable about a line S 1  as an axis. The movement of the first holder  110  is implemented by a first actuator  114  provided to the first holder  110 . The configuration in which the first actuator and the first holder are disposed to be movable can be implemented using conventional ones known in the art, and therefore, its detailed description will be omitted. 
         [0053]    The second holder  120  is disposed adjacent to the first holder  110 . Like the first holder  110 , a plurality of absorption holes  122  are also formed in a holding surface  121  of the second holder  120  so as to generate negative pressure. The absorption holes  122  formed in the second holder  120  are provided as a film holder for allowing the film  60  to be absorbed and fixed to the holding surface  121 . 
         [0054]    Meanwhile, first and second cameras  130  and  132  are provided around the first holder  110 . The first and second cameras  130  and  132  recognize the position of the plate member  50  and transmits the recognized position to a controller (not shown), so that the controller controls the film and the plate member to be aligned in a laminating process of the film. The controller is electrically connected to the first actuator  114  so as to control the position of the first holder  110 , based on information obtained by the cameras  130  and  132 . 
         [0055]    A rail  140  is provided above the first and second holders  110  and  120 . The rail  140  is formed longer than the region on which the first and second holders  110  and  120  are disposed. The rail  140  is configured to be ascended and descended in the vertical direction by a pair of cylinders  141  respectively provided at both end portions thereof. A slider  143  horizontally moving along the rail  140  is mounted to the rail  140 . The slider  143  has a self-driving means, and the movement of the slider  143  is controlled by the controller. 
         [0056]    A pressing roll  150  is rotatably mounted beneath the slider  143 . In  FIG. 2 , the pressing roll  150  rotates clockwise or counterclockwise. Meanwhile, the pressing roll  150  may be configured to be rotatable about a line S 2  as a center axis by a driving motor  142  provided on the slider  143 . Thus, the pressing roll  150  is controlled so that the previously set position of the pressing roll  150  can be maintained in the process of coating the film on the plate member. In addition, the pressing roll  150  can move to an arbitrary position on the first and second holding surfaces  111  and  121 . 
         [0057]    Meanwhile, a cut-away portion is provided to the pressing roll  150 . The cut-away portion includes a first cut-away surface  151  extended to the center from a circumferential surface of the pressing roll  150 , and a second cut-away surface  152  extended to the circumferential surface in the perpendicular direction from an end portion of the first cut-away surface  151 . The cut-away portion is formed to coat the film  60  on the plate member  50  at a lower portion of the bending portion  51  of the plate member  50 , which will be described later. 
         [0058]      FIG. 3  is a perspective view illustrating the pressing roll  150 . As shown in this figure, a plurality of absorption holes  153  are formed in the surface of the pressing roll  150 , so that the film can be absorbed to the surface of the pressing roll  150 . A stainless net  154  is stacked on the surface of the pressing roll  150 . The stainless net  154  is provided to prevent marks from being formed on the surface of the film due to pressure applied in the laminating process of the film. 
         [0059]    That is, in a case where the stainless net  154  is not provided, marks corresponding to the shapes of the absorption holes  153  are formed on the film when the film is pressed on the plate member. However, the stainless net  154  can prevent the absorption holes  153  from directly contacting the film while providing negative pressure to the film. Here, the stainless net  154  is made of a stainless material for the purpose of corrosion prevention, etc., but the present disclosure is not necessarily limited thereto. For example, the stainless net  154  may be made of an arbitrary material. 
         [0060]      FIG. 4  is a side view illustrating a process of transferring the film  60  absorbed and fixed to the second holder  120  to the surface of the pressing roll  150 . Referring to  FIG. 4 , the film  60  maintains the state in which the film  60  is absorbed to the surface of the second holder  120  due to the negative pressure formed in the absorption holes  122 . In this state, the pressing roll  150  is positioned so that a position P 1  at the end portion of the first cut-away surface  151  is aligned at the left end of the film  60 , and then transfers the film  60  to the surface of the pressing roll  150  while rotating and moving in the direction of arrows shown in  FIG. 3 . 
         [0061]    Here, the negative pressure applied to the holding surface of the second holder  120  is set to be smaller than that applied to the surface of the pressing roll  150 , and therefore, the film  60  is absorbed to the second holder  120  in the state in which an external force is not applied. However, if the pressing roll  150  contacts the film  60 , the film  60  is separated from the second holder  120  and then transferred to the pressing roll  150 . 
         [0062]    As such, the entire film is transferred to the surface of the pressing roll  150  while the pressing roll  150  is rotating. In this case, the length of the outer circumferential surface of the pressing roll  150  except the cut-away portion is formed identical to or greater than that of the film. In  FIG. 4 , the length of the film is set to be smaller than that of the pressing roll  150 , and therefore, the one end portion of the film is placed at a position P 2  at which the second cut-away surface  152  does not approach. 
         [0063]      FIG. 5  is a side view illustrating a process of laminating the film attached to the pressing roll  150  on the plate member  50 . Referring to  FIG. 5 , the pressing roll  150  is moved from the second holder  120  to the first holder  110  by the slider and the rail and then approaches the plate member  50  while descending toward the plate member  50  on the first holder  110 . 
         [0064]    In this case, the position P 1  is aligned to reach the intersection point of the bending portion  51  and the plate member  50 . Then, the film is laminated on the surface of the plate member  50  while the pressing roll  150  is rotating in the direction of arrows shown in  FIG. 5 . In this case, the length of the film is trimmed to be suitable for the length of the plate member  50 . Thus, if the position P 1  is aligned at a predetermined position, the position P 2  is aligned with the end portion of the plate member  50 . Meanwhile, a protective film for protecting an adhesive layer coated on the film is attached on the surface of the film. Thus, after the protective film is removed, the film is laminated on the plate member  50  by rotating and moving the pressing roll  150  in the direction of the arrows. 
         [0065]    Here, the negative pressure formed in the pressing roll  150  is set to be smaller than the adhesion of the adhesive layer of the film, so that the laminated film is not again transferred to the pressing roll  150 . 
         [0066]    Meanwhile, before being placed on the second holder, the film  50  is cut away to have a desired shape through a trimming process.  FIG. 6  illustrates an example of a trimming device. Referring to  FIG. 6 , the trimming device  200  uses a film  50  supplied in the state in which the film  50  is wound around a supply roll  12 , and includes two tension rolls  210  and  212  for controlling tension of the film  50  supplied from the supply roll  12  to an appropriated level. An extraction roll  12 ′ for extracting the film remaining after the trimming process is provided at a rear end of the tension roll  212 . 
         [0067]    The film  50  supplied by the supply roll  12  is transferred to the inside of a cutting machine  220  by a conveyor belt  214  driven by a driving motor  216 . The transferred film is cut away in a predetermined shape by a cutter  222  provided to the cutting machine  220 . The film can be cut away in the exact shape by a sensor  224  for sensing the length and position of the supplied film. A holder  230  for preventing the movement of the film in the cutting process is additionally provided at the entrance of the cutting machine  220 . 
         [0068]    The films cut away by the trimming device  200  are supplied one by one to the second holder so as to be laminated on the plate member. 
         [0069]    In a case where the width of the laminated film is constant, e.g., in a case where the film has a rectangular shape, the trimming device and the second holder may be omitted. In this case, in the conventional film laminating apparatus shown in  FIG. 1 , the plate member is not supplied to the roller  30  but may be supplied in the state in which the plate member is absorbed by the first holder. In a case where the bending portion  51  described above is not provided to the plate member, the cut-away portion formed in the pressing roll  150  may be omitted, and the pressing roll  150  may have a general circumferential shape. 
         [0070]    Hereinafter, a method of laminating a film on a plate member according to an exemplary embodiment will be described with reference to  FIG. 7 . 
         [0071]    First, the film is cut away in a predetermined shape, using the trimming device. Specifically, a raw film supplied in the shape of a winding roll is loaded into the trimming device  200  (S 10 ), and the position of the supplied film is confirmed through the sensor  224  (S 02 ). Then, the film is cut away in a predetermined shape through the cutting machine  220  (S 03 ). Here, the shape of the cut film is determined in consideration of the state to be deformed through the following absorption process of a plate member. That is, if the shape of the plate member is changed from a straight line into a curved line, The cut film is necessarily cut away in the curved line, corresponding to the shape of the deformed plate member. This is applied to a case where the film is laminated on the entire surface of the plate member and a case where the film is laminated on a partial surface of the plate member. 
         [0072]    However, in a case where the degree of deformation is not large, the film may be cut away without considering the deformation. 
         [0073]    Subsequently, the cut film is supplied and absorbed to the holding surface  121  of the second holder  120  described in the aforementioned exemplary embodiment (S 04 ), the position of the absorbed film is confirmed using a camera is (S 05 ). Then, the film is aligned with respect to the pressing roll  150  (S 06 ). In the alignment process, the film may be aligned by moving the second holder having the film held thereby. Alternatively, the film may be aligned by controlling the position of the pressing roll  150  as described above. 
         [0074]    If the alignment of the film is completed, the film is absorbed to the surface of the pressing roll (S 07 ), and a protective film attached to the surface of the film is removed (S 08 ). The protective film may be manually removed or may be removed using a separate device or tool for removing the protective film. 
         [0075]    Meanwhile, separately from the trimming process, the plate member is washed using a washing device shown in  FIG. 1 . That is, after water is sprayed onto the surface of the plate member, foreign matters are removed using the brush (S 11 ), and the plate member is then dried (S 12 ). The plate member washed and dried as described above is held on the holding surface  111  of the first holder  110  (S 13 ). Then, the plate member deformed and absorbed on the holding surface by applying negative pressure to the plate member using the vacuum pump (S 14 ). In a case where the initial shape of the plate member is flat, the deformation of the plate member may not be performed. 
         [0076]    The position of the absorbed plate member is confirmed using the camera (S 15 ), and then aligned with respect to the pressing roll (S 16 ). If the procedure up to step S 16  is completed, the position between the film and the plate member is aligned in a predetermined state, and therefore, the film is laminated on the surface of the plate member as described in  FIG. 5  (S 20 ). If the lamination of the film is completed, the plate member is restored to the shape of the plate member before being deformed by removing the negative pressure applied to the absorption holes (S 24 ). Then, the film laminating process is completed through inspection (S 25 ). 
         [0077]    The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments. 
         [0078]    As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.