Abstract:
An attaching apparatus for attaching an optical film to a workpiece includes a workbench ( 11 ) for supporting the workpiece and the optical film; a roller device ( 40 ) for rolling the optical film into attachment with the workpiece. Either or both the roller device and the workbench are movable relative to the other. Aligning the optical film and turning the workpiece manually can be reduced. The attaching apparatus reduces manual labor and costs, and increases efficiency.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to an attaching apparatus for attaching optical films onto workpieces, and particularly to an attaching apparatus typically used to attach a reflective film to a light guide plate (LGP) of a liquid crystal display (LCD).  
         [0003]     2. General Background  
         [0004]     A backlight module of an LCD generally includes an LGP, a light source, a reflective film, and a prism plate. The light source is arranged opposite to a light incident surface of the LGP, the reflective film is arranged adjacent to a bottom surface of the LGP, and the prism plate is arranged adjacent to a light emitting surface of the LGP. The reflective film is attached to other side surfaces of the LGP, in order to prevent light from leaking.  
         [0005]     A typical method of attaching a reflective film to an LGP is performed by aligning the reflective film and turning the LGP manually. This method may cause gaps to be formed between the reflective film and the LGP. Further, manual labor can be costly and inefficient.  
         [0006]     What is needed, therefore, is an attaching apparatus for attaching a reflective film to an LGP, whereby the attachment can be effected accurately and efficiently.  
       SUMMARY  
       [0007]     In one preferred embodiment, an attaching apparatus for attaching an optical film to a workpiece includes a workbench for supporting the workpiece and the optical film; a roller device for rolling the optical film into attachment with the workpiece. Either or both the roller device and the workbench are movable relative to the other. Aligning the optical film and turning the workpiece manually can be reduced. The attaching apparatus reduces manual labor and costs, and increases efficiency.  
         [0008]     Other advantages and novel features will become more apparent from the following detailed description of preferred embodiments when taken in conjunction with the accompanying drawings, in which: 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]      FIG. 1  is an isometric view of an attaching apparatus used to attach a reflective film to an LGP, according to a preferred embodiment of the present invention;  
         [0010]      FIG. 2  is an enlarged, exploded view of a support frame of the attaching apparatus of  FIG. 1 ;  
         [0011]      FIG. 3  is an enlarged, exploded view of a workbench unit of the attaching apparatus of  FIG. 1 ;  
         [0012]      FIG. 4  is an enlarged view of an elastic supporting device of the attaching apparatus of  FIG. 1 ;  
         [0013]      FIG. 5  is an enlarged, exploded view of a roller device of the attaching apparatus of  FIG. 1 ;  
         [0014]      FIG. 6  is an exploded view of a roller of the roller device of  FIG. 5 ;  
         [0015]      FIG. 7  is an enlarged, end view of the roller of the roller device of  FIG. 5 ;  
         [0016]      FIG. 8  is similar to  FIG. 1 , but showing a reflective film and an LGP engaged on the attaching apparatus prior to operation of the attaching apparatus to attach the reflective film onto sides of the LGP; and  
         [0017]      FIG. 9  is similar to  FIG. 8 , but showing the reflective film attached onto the sides of the LGP after operation of the attaching apparatus. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0018]     Reference will now be made to the drawings to describe the preferred embodiments in detail.  
         [0019]     Referring to  FIG. 1 , an attaching apparatus for attaching a reflective film to an LGP in accordance with the preferred embodiment of the present invention includes a support frame  20 , a workbench unit  10 , an elastic supporting device  30 , and two roller devices  40 .  
         [0020]     Referring to  FIG. 2 , the support frame  20  includes a table  21 , and two side supports  22  and  23  supporting the table  21 . The table  21  includes a screw hole  211  and a plurality of fixing holes  212 . The screw hole  211  and the fixing holes  212  are all through holes. Each side support  22 ,  23  defines a cutout  221 ,  231 , such that each side support  22 ,  23  has a pair of legs. The legs provide steady support for the attaching apparatus.  
         [0021]     Referring to  FIG. 3 , the workbench unit  10  includes a workbench  11 , two fixing plates  12 , a plurality fixing holes  112 , and a positioning strip  113 . The workbench  11  further includes a raised, L-shaped positioning strip  113  formed on two adjacent edge portions of the workbench  11 . The two fixing plates  12  are arranged on the positioning strip  113 , and overhang the workbench  11 . Therefore an L-shaped space is defined between the workbench  11  and the fixing plates  12 . The fixing holes  112  of the workbench  11  are located corresponding to the fixing holes  212  of the table  21 .  
         [0022]     Referring to  FIG. 4 , the elastic supporting device  30  includes two elastic elements  36 , a holding bolt  32 , and a plurality of support elements  37 . Each elastic element  36  includes a guide spindle  31 , and a spring  35  positioned around the guide spindle  31 . Each support element  37  includes a guide spindle  31 ′, an annular flange  34  formed around the guide spindle  31 ′, and a snap ring attached to a bottom end of the guide spindle  31 ′.  
         [0023]     Referring to  FIG. 5  through  FIG. 7 , each roller device  40  includes two flexible strips  43 , two L-shaped brackets  42 , and a roller  41 . Each flexible strip  43  defines a plurality of screw holes (not labeled) for fixing the roller device  200  to the support frame  20 . Each L-shaped bracket  42  has an indentation  421  in a distal end of a short side thereof, for receiving a corresponding end of the roller  41  therein. Each L-shaped bracket  42  also has a slot  422  along a long side thereof, for attachment of a corresponding flexible strip  43  to the L-shaped bracket  42  with the aid of a screw (not labeled) and a nut (not labeled). The roller  41  includes a revolving shaft  413 , a revolving drum  412  located around the revolving shaft  413 , and a rubber layer  411  covering the revolving drum  412 . The revolving drum  412  can turn around the revolving shaft  413 . Two ends (not labeled) of the revolving shaft  413  are respectively received in the indentations  421  of the L-shaped brackets  42 , whereby the L-shaped brackets  42  support and hold the roller  41 .  
         [0024]     In assembly, the table  21  is fixed between the two side supports  22 ,  23  by screws (not labeled), thereby obtaining the support frame  20 . The guide spindles  31  of the elastic elements  36  and the guide spindles  31 ′ of the support elements  37  are received through the corresponding fixing holes  212  of the table  21 . The springs  35  are located around the guide spindles  31 . The snap rings  33  are engaged around bottoms of the guide spindles  31 ′ of the support elements  37 . Thus the flanges  34  and the snap rings  33  are disposed at top and bottom sides of the table  21  respectively, such that the support elements  37  are secured in the corresponding fixing holes  212  of the table  21 . The holding bolt  32  is engaged in the screw hole  211  of the table  21 , down to a predetermined distance away from the workbench  11 . The workbench unit  10  is then engaged on the elastic supporting device  30 , with the fixing holes  112  receiving top ends of the guide spindles  31 ,  31 ′. The workbench  11  is thus elastically supported on the springs  35  of the elastic elements  36 , with the springs  35  held between the workbench  11  and the table  21 . One of the roller devices  40  is fixed to top portions of front ends of the side supports  23 , by screw attachment of the flexible strips  43  to the side supports  23 . The other roller device  40  is fixed to top portions of opposite sides of one of the side supports  23 , by screw attachment of the flexible strips  43  to that side support  23 . The two roller devices  40  are thus disposed at two adjacent sides of the support frame  20 , with each roller  41  inclined relative to the workbench  11 . An elbow defined where the rollers  41  meet is diagonally opposite from an elbow of the positioning strip  113 . Thus the support frame  20  supports and locates the workbench unit  10  by way of the elastic supporting device  30  and the roller devices  40 .  
         [0025]     Referring to  FIG. 8  and  FIG. 9 , a process of using the attaching apparatus to attach a reflective film to an LGP comprises the following steps. Firstly, an LGP  50  with a reflective film  60  is placed on the workbench  11 . Two adjacent edges of the reflective film  60  are arranged in the space between the workbench  11  and the fixing plates  12 . The LGP  50  is located such that two adjacent fixing plate sides thereof abut against the positioning strip  113  and are held by the fixing plates  12 . Two adjacent edge portions (not labeled) of the reflective film  60  opposite the rollers  41  protrude out from the LGP  50  and the workbench  11 . A common width of the edge portions corresponds to a thickness of the LGP  50 . Secondly, the LGP  50  and the workbench unit  10  are pressed down until the workbench unit  10  touches the holding bolt  32 . During this process, the rollers  41  turn and press roll the edge portions of the reflective film  60 . Because the rollers  41  are inclined relative to the workbench  11 , they maintain certain pressures on the two edge portions of the reflective film  60  as the LGP  50  descends, whereby the two edge portions of the reflective film  60  are attached to corresponding side surfaces of the LGP  50 . Thirdly, the pressure on the LGP  50  is removed. The LGP  50  and the workbench  11  rise to their original positions because of decompression of the springs  35 . Finally, the LGP  50  with the reflective film  60  attached thereon is taken off from the workbench  11 .  
         [0026]     With the fixing plates  12  and the positioning strip  113 , the attaching apparatus of the preferred embodiment can precisely align the LGP  50  and the reflective film  60  before the reflective film  60  attaching process is performed. Furthermore, the LGP  50  and the reflective film  60  are protected from damage by the flexibility of the rubber layers  411 . Moreover, the holding bolt  32  can adjustably limit the lowest position attainable by the workbench unit  10 . The attaching apparatus reduces manual labor and costs, and increases efficiency.  
         [0027]     In alternative embodiments, the snap rings  33  can replaced by, for example, the following fastening means. Bottom ends of the guide spindles  31 ′ can be threaded, and nuts can be engaged onto these bottom ends. The holding bolt  32  can instead be a holding pillar adjustably or non-adjustably arranged on the table  21 . The L-shaped brackets  42  can be omitted. This can be done by changing the shape of each flexible strip  43 , so that an end of the modified flexible strip  43  directly connects with a corresponding end of the corresponding revolving shaft  413 . The rubber layer  411  of each roller device  40  can be omitted, particularly if the revolving drum  412  of the roller device  40  is made from a suitable elastic material. The positioning strip  113  can be omitted, with the fixing plates  12  being modified to include portions that cooperatively function as a protrude unit. The number of guide spindles  31 , flanges  34 , springs  35  and snap rings  33  of the elastic supporting device  30  can be determined according to need. Only a single roller  40  may be employed, if only one side surface of the LGP  50  needs to have a portion of the reflective film  60  attached thereto.  
         [0028]     It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the invention.