JP6033053B2 - Optical sheet processing equipment - Google Patents

Description

  The present invention relates to an optical sheet processing apparatus and method for forming an uneven portion on a light incident end face of an optical sheet.

  An example of the optical sheet is a light guide plate used in a backlight unit of a liquid crystal display device. In the edge-light type backlight unit, a plurality of light sources are arranged in an array facing the light incident end face of the light guide plate, and light incident from the light incident end face of the light guide plate is emitted from the light exit surface, thereby liquid crystal Illuminate the display panel. However, in the edge light type backlight unit, luminance unevenness occurs in the illumination light emitted from the vicinity of the light incident end surface of the light exit surface of the light guide plate.

  In order to solve such a problem, for example, as described in Patent Document 1, a technique in which a cut and polished surface is formed on a light incident end surface of a light guide plate is known. The cutting and polishing surface described in Patent Document 1 is a rough surface having a large number of fine vertical irregularities extending in a direction perpendicular to the light emitting surface of the light guide plate.

JP 2010-182478 A

  However, in the above prior art, the cutting and polishing surface is formed on the light incident end surface of the light guide plate by machining using a machine tool such as a milling machine, NC router, or planar, so that chips are generated by cutting. . For this reason, cutting powder mixes and adheres to the light guide plate, resulting in poor quality.

  The objective of this invention is providing the optical sheet processing apparatus and method which can prevent mixing and adhesion of the swarf to an optical sheet.

  The present invention is an optical sheet processing apparatus for forming a concavo-convex portion on a light incident end surface of an optical sheet made of a thermoplastic resin, and is made of a metal having a transfer surface for imparting a concavo-convex portion to a light incident end surface of an optical sheet. Pressure is applied to the stage so that the transfer roll, a pair of stages that support the optical sheet, a heating unit that heats the transfer roll, and the transfer surface and the light incident end surface are pressed against each other. It is characterized by comprising a pressure applying means, a rotating means for rotating the transfer roll, and a moving means for moving the stage with respect to the transfer roll in the direction of forming the concavo-convex portion.

  Using such an optical sheet processing apparatus of the present invention, when forming a concavo-convex portion on the light incident end surface of an optical sheet made of a thermoplastic resin, the metal transfer roll is heated and the transfer surface of the transfer roll and While the pressure is applied to the stage so that the light incident end faces of the optical sheet are pressed against each other, the optical sheet is made incident by moving the stage in the direction of forming the concavo-convex part with respect to the transfer roll while rotating the transfer roll. An uneven portion is provided on the end face. Thereby, unlike the case where an uneven | corrugated | grooved part is formed by cutting, since a swarf does not generate | occur | produce, the mixing and adhesion of the swarf to an optical sheet can be prevented.

  In addition, by arranging a pair of stages that support the optical sheet so as to sandwich the transfer roll, uneven portions can be formed on the light incident end face of the optical sheet on both sides of the transfer roll. Specifically, the optical sheet supported by the other stage is not formed during the period in which the concave and convex portions are formed on the light incident end face of the optical sheet supported by one stage (for example, the period during which the optical sheet is inserted or removed). An uneven portion can be formed on the light incident end face. In this case, it is not necessary to interrupt the process of forming the concavo-convex portion on the light incident end face of the optical sheet for loading and unloading the optical sheet. Thereby, the processing tact of an optical sheet can be improved.

  Preferably, the rotating means has a pair of motors provided corresponding to each stage, and a rotation power transmission mechanism for transmitting the driving force of each motor to the transfer roll. And a moving power transmission mechanism for transmitting the driving force of each motor to each stage. In this case, since a pair of motors are shared as components of the rotating means and moving means, it is not necessary to separate the motor for rotating the transfer roll and the motor for moving each stage, and the number of motors to be used. Can be minimized.

  At this time, it is preferable that the rotational power transmission mechanism is connected to a first spur gear attached to the roll shaft of the transfer roll, a pair of second spur gears that mesh with the first spur gear, and each second spur gear. Each of the motors has a pair of clutches for interrupting transmission of the driving force, and the power transmission mechanism for movement is attached to each of the pair of racks provided on each stage and the output shaft of each motor. , And a pair of pinions that mesh with each rack. In this case, the rotation power transmission mechanism and the movement power transmission mechanism can be realized with a simple configuration.

  Moreover, this invention is an optical sheet processing method which forms an uneven | corrugated | grooved part in the light-incidence end surface of the optical sheet which consists of thermoplastic resins, Comprising: While preparing the said optical sheet processing apparatus, heating a transfer roll, In the state where pressure is applied to the stage so that the transfer surface and the light incident end surface are pressed to each other, the stage is moved in the direction of forming the concavo-convex portion with respect to the transfer roll while rotating the transfer roll. A forming step for forming an uneven portion, and in the forming step, the optical sheet supported on one of the pair of stages is supported on the other of the pair of stages while the uneven portion is not formed on the light incident end surface. An uneven portion is formed on the light incident end face of the optical sheet thus formed.

  In such an optical sheet processing method of the present invention, the transfer roll is heated and the transfer roll is rotated in a state where pressure is applied to the stage so as to press the transfer face of the transfer roll and the light incident end faces of the optical sheet. Then, by moving the stage in the formation direction of the concavo-convex portion with respect to the transfer roll, the concavo-convex portion is imparted to the light incident end surface of the optical sheet. Thereby, unlike the case where an uneven | corrugated | grooved part is formed by cutting, since a swarf does not generate | occur | produce, the mixing and adhesion of the swarf to an optical sheet can be prevented.

  In addition, the light incident end surface of the optical sheet supported by the other stage during a period in which the uneven portion is not formed on the light incident end surface of the optical sheet supported by one stage (for example, the period during which the optical sheet is inserted or removed) By forming the concavo-convex portion on the optical sheet, it is not necessary to interrupt the step of forming the concavo-convex portion on the light incident end surface of the optical sheet in order to load and unload the optical sheet. Thereby, the processing tact of an optical sheet can be improved.

  Preferably, in the molding step, while the optical sheet is being taken out from one stage, the other stage is moved from one side to the other side, and the light incident end surface of the optical sheet supported by the other stage is moved. After carrying out the first step for forming the concavo-convex portion and the first step, while taking out the optical sheet from the other stage, one stage is moved from one side to the other side, and one stage is moved. The second step of forming the concavo-convex portion on the light incident end face of the optical sheet supported by the optical sheet, and after performing the second step, while the optical sheet is being taken out from the one stage, the other stage is moved to the other side. A third step of forming an uneven portion on the light incident end face of the optical sheet supported by the other stage by moving from the first side to the one side, and taking out the optical sheet from the other stage after performing the third step While performing the one stage is moved to one side from the other side, and a fourth step of forming an uneven portion to the light incident face of the optical sheet supported on one stage. In this case, the concave and convex portions can be formed on the light incident end face from both directions for both the optical sheet supported by one stage and the optical sheet supported by the other stage.

  Further, in the molding process, while the optical sheet is being taken out from one stage, the other stage is moved from one side to the other, and the light incident end face of the optical sheet supported by the other stage is uneven. The first step for forming the part, the second step for moving the other stage from the other side to the one side, and the second step while one stage is waiting after the first step is performed After that, while taking out the optical sheet from the other stage, one stage is moved from the other side to one side to form an uneven portion on the light incident end face of the optical sheet supported by one stage. The third step may include a fourth step of moving one stage from one side to the other side while the other stage is waiting after the third step is performed. In this case, the number of workers can be reduced because there is only one worker on one side and the other side of the optical sheet processing apparatus.

  Further, in the molding process, while the optical sheet is being taken out from one stage, the other stage is moved from one side to the other, and the light incident end face of the optical sheet supported by the other stage is uneven. The first step for forming the part, the second step for moving the other stage from the other side to the one side, and the second step while one stage is waiting after the first step is performed After that, while taking out the optical sheet from the other stage, one stage is moved from one side to the other to form a concavo-convex portion on the light incident end surface of the optical sheet supported by one stage. And a fourth step of moving one stage from the other side to the one side while the other stage is waiting after the third step is performed. In this case, since it is sufficient that there are two workers on one side of the optical sheet processing apparatus, the number of workers can be reduced. Also, even if it is difficult for a worker to work on the other side of the optical sheet processing apparatus because there is a wall or the like on the other side of the optical sheet processing apparatus, the work can be performed without trouble on one side of the optical sheet processing apparatus. It can be performed.

  According to the present invention, it is possible to prevent chips from being mixed and adhered to the optical sheet. As a result, the quality of the optical sheet can be stabilized and the yield can be improved. Moreover, the processing tact of the optical sheet can be increased and the productivity can be improved.

It is a schematic sectional drawing which shows the liquid crystal display device containing the light-guide plate which is an optical sheet obtained by one Embodiment of the optical sheet processing apparatus concerning this invention. It is a perspective view of the light-guide plate shown in FIG. It is a flowchart which shows the process of manufacturing the light-guide plate shown in FIG. It is a top view which shows one Embodiment of the optical sheet processing apparatus concerning this invention. It is a front view of the optical sheet processing apparatus shown in FIG. It is VI-VI line principal part sectional drawing of FIG. It is a principal part enlarged view of FIG. It is an VIII-VIII line principal part expanded sectional view of FIG. It is a perspective view which shows roughly the optical sheet processing apparatus shown in FIG. It is a conceptual diagram which shows the process of shape | molding a light-guide plate using the optical sheet processing apparatus shown in FIG. It is a conceptual diagram which shows the other process of shape | molding a light-guide plate using the optical sheet processing apparatus shown in FIG. It is a conceptual diagram which shows the further another process of shape | molding a light-guide plate using the optical sheet processing apparatus shown in FIG. In the optical sheet processing apparatus shown in FIG. 4 etc., it is a figure which shows the modification of the mechanism in which a transfer roll is rotated and a stage is moved.

  Hereinafter, an optical sheet processing apparatus and method according to the present invention will be described in detail with reference to the drawings. In the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic sectional view showing a liquid crystal display device including a light guide plate which is an optical sheet obtained by one embodiment of an optical sheet processing apparatus according to the present invention. In the figure, a liquid crystal display device 1 according to this embodiment is used for a liquid crystal television, for example. The liquid crystal display device 1 includes a liquid crystal panel 2 and an edge-type backlight unit 3 disposed on the back side of the liquid crystal panel 2. The thickness of the liquid crystal panel 2 is, for example, about 1.8 mm.

  The backlight unit 3 has a box-shaped metal backlight housing 4. A plurality of electronic components 5 are provided on the back surface (back surface) of the backlight housing 4 via a substrate (not shown). A plurality of LEDs 6 that irradiate light are attached to the opposing inner wall surfaces of the backlight housing 4.

  In the backlight housing 4, a light guide plate 7 having a rectangular cross section for guiding the light emitted from the LEDs 6 to the liquid crystal panel 2 is accommodated via a reflection sheet 8. As shown in FIG. 2, the light incident end surface 7 a of the light guide plate 7 is provided with a concavo-convex portion 9 having a substantially corrugated cross section. The thickness of the light guide plate 7 is, for example, 3 mm.

  The light guide plate 7 is made of a thermoplastic resin. Specifically, the light guide plate 7 is made of an amorphous resin having high dimensional accuracy, impact strength, and transparency. Examples of the amorphous resin include polymethyl methacrylate resin (PMMA), polystyrene (PS), polycarbonate (PC), and cycloolefin polymer (COP).

  The light emitted from the LED 6 is incident on the light incident end surface 7 a of the light guide plate 7. The back surface of the light guide plate 7 is a reflective surface that reflects the light emitted from the LED 6, and the front surface of the light guide plate 7 is a light exit surface that emits the light emitted from the LED 6 and the light reflected by the reflective surface. It has become. The back surface (reflection surface) of the light guide plate 7 has a structure that easily reflects and scatters light, such as dot pattern printing with ink.

  On the front side of the light guide plate 7, an optical film group 10 formed by laminating a plurality of (here, three) optical films is disposed. The thickness of the optical film group 10 is, for example, about 0.2 mm. The edges of the light guide plate 7 and the optical film group 10 are fixed to the backlight housing 4 by a frame body 11 made of resin (for example, PC). The liquid crystal panel 2 is fixed to the backlight unit 3 by a metal frame body 12.

  FIG. 3 is a flowchart showing a process for manufacturing the light guide plate 7. In the figure, first, a light guide plate original plate is produced by a melt extrusion sheet forming process or the like (step S101). Subsequently, the light guide plate original plate is roughly cut with a panel saw, a running saw, or the like to obtain the light guide plate 7 (step S102). Subsequently, mirror processing is performed on the light incident end surface 7a of the light guide plate 7 using a mirror processing machine (step S103). Then, the uneven | corrugated | grooved part 9 is formed in the light-incidence end surface 7a by performing a thermal transfer process to the light-incidence end surface 7a of the light-guide plate 7 (step S104). Note that step S103 is not necessarily performed.

  FIG. 4 is a plan view showing an embodiment of an optical sheet processing apparatus according to the present invention. 5 is a front view of the optical sheet processing apparatus shown in FIG. 4, FIG. 6 is a sectional view taken along the line VI-VI in FIG. 5, and FIG. 7 is an enlarged view of the relevant part in FIG. 8 is an enlarged cross-sectional view taken along the line VIII-VIII in FIG. FIG. 9 is a perspective view schematically showing the optical sheet processing apparatus shown in FIG. In each figure, the optical sheet processing apparatus 20 of this embodiment is used when step S104 shown in FIG. 3 is performed.

  The optical sheet processing apparatus 20 includes an apparatus frame 21. A rack 22 is disposed at the center of the apparatus frame 21, and a metal transfer roll 23 is rotatably supported on the rack 22 (see FIG. 6). As shown in FIG. 9, a transfer uneven portion 19 is formed on the outer peripheral surface 23 a of the transfer roll 23 along the circumferential direction of the transfer roll 23. The outer peripheral surface 23 a of the transfer roll 23 is a transfer surface for imparting an uneven portion to the light incident end surface 7 a of the light guide plate 7. The transfer uneven portion 19 is formed in a prism shape or a lenticular shape with respect to the roll axis direction of the transfer roll 23, for example.

  As shown in FIG. 6, the transfer roll 23 is an electric heater roll in which an induction coil 41 (heater unit) is built. On the upper side of the transfer roll 23, a power supply unit 42 for supplying a high-frequency current to the induction coil 41 is disposed. The induction coil 41 and the power supply unit 42 constitute a heating unit that heats the transfer roll 23. As the transfer roll 23, an oil heater roll heated by oil may be used.

  As shown in FIG. 5, pedestals 25 </ b> A and 25 </ b> B are arranged below the apparatus frame 21 so as to sandwich the transfer roll 23 in the apparatus left-right direction (X direction). Stage bases 26A and 26B are attached to the upper portions of the pedestals 25A and 25B so as to be movable in the longitudinal direction of the apparatus (Y direction) via guide rails 27A and 27B, respectively. Stages 28A and 28B are mounted on the upper portions of the stage bases 26A and 26B so as to be movable in the left-right direction (X direction) of the apparatus via guide rails 29A and 29B, respectively.

  The light guide plate 7 is placed (supported) on the upper surfaces of the stages 28A and 28B. On the upper surfaces of the stages 28A and 28B, light guide plates 7 of various sizes can be placed vertically or horizontally (see FIG. 4). The vertical placement is a placement method in which the longitudinal direction of the light guide plate 7 is matched with the Y direction. The horizontal placement is such that the longitudinal direction of the light guide plate 7 coincides with the X direction. The light guide plate 7 placed on the upper surfaces of the stages 28A and 28B is positioned by positioning means not described in detail. The light guide plate 7 placed on the upper surfaces of the stages 28A and 28B is pressed against the stages 28A and 28B by the clamp plates 18A and 18B (see FIG. 9).

  Press cylinders 30A and 30B for moving the stages 28A and 28B in the X direction are attached to the upper portions of the stage bases 26A and 26B, respectively (see FIG. 5). The pressure cylinders 30A and 30B are pressure applying means for applying pressure to the stages 28A and 28B so as to press the light incident end surface 7a of the light guide plate 7 placed on the stages 28A and 28B against the transfer surface 23a of the transfer roll 23. Is configured.

  5 to 8, the optical sheet processing apparatus 20 is disposed so as to sandwich the transfer roll 23 in an oblique direction with respect to the X direction and the Y direction corresponding to the stages 28A and 28B. Serving motors 31A and 31B are provided. Pinion gears 32A and 32B are attached to the output shafts 31a of the forming servomotors 31A and 31B, respectively. Rack gears 33A and 33B extending in the Y direction and meshing with the pinion gears 32A and 32B are provided on the inner side surfaces of the lower portions of the stage bases 26A and 26B, respectively. As a result, when the molding servomotors 31A and 31B are driven to rotate, the rotation of the molding servomotors 31A and 31B is transmitted to the stage bases 26A and 26B via the pinion gears 32A and 32B and the rack gears 33A and 33B. , 26B move in the Y direction, and accordingly the stages 28A, 28B move in the Y direction.

  Shafts 34 </ b> A and 34 </ b> B extending in the vertical direction (Z direction) of the apparatus are rotatably supported at the lower portion of the rack 22. These shafts 34A and 34B are arranged so as to sandwich the transfer roll 23 in the Y direction. Spur gears 35A and 35B that mesh with the above-described pinion gears 32A and 32B are provided in the middle portions of the shafts 34A and 34B, respectively. Electromagnetic clutches 36A and 36B are attached to the upper ends of the shafts 34A and 34B, respectively.

  Although not specifically described in detail, the shafts 34A and 34B and the spur gears 35A and 35B have a rotary ball spline structure, and the shafts 34A and 34B can move up and down with respect to the spur gears 35A and 35B. The rack 22 can be lifted and lowered by a lifting means, and the transfer roll 23 can be lifted and lowered accordingly.

  A support plate 22 a is connected to the rack 22. Shafts 37A and 37B extending downward are rotatably supported at portions corresponding to the shafts 34A and 34B in the support plate 22a. Spur gears 38A and 38B are provided in the middle portions of the shafts 37A and 37B, respectively. The lower ends of the shafts 37A and 37B are attached to the electromagnetic clutches 36A and 36B, respectively.

  The electromagnetic clutch 36A interrupts the transmission of power from the spur gear 35A to the spur gear 38A by intermittently connecting the shafts 34A and 37A. Specifically, when the electromagnetic clutch 36A is ON, the shafts 34A and 37A are connected to each other, and when the electromagnetic clutch 36A is OFF, the connections between the shafts 34A and 37A are released. The electromagnetic clutch 36B interrupts the transmission of power from the spur gear 35B to the spur gear 38B by intermittently connecting the shafts 34B and 37B. Specifically, when the electromagnetic clutch 36B is ON, the shafts 34B and 37B are connected to each other, and when the electromagnetic clutch 36B is OFF, the connections between the shafts 34B and 37B are released.

  A roll shaft 23 b of the transfer roll 23 extends below the rack 22. A spur gear 39 that meshes with the spur gears 38A and 38B is attached to the lower end of the roll shaft 23b.

  When the forming servomotor 31A is driven to rotate with the electromagnetic clutch 36A turned on, transfer is performed via the pinion gear 32A, spur gear 35A, shaft 34A, electromagnetic clutch 36A, shaft 37A, spur gear 38A and spur gear 39. The roll 23 rotates. Further, when the forming servo motor 31B is rotated with the electromagnetic clutch 36B turned on, the pinion gear 32B, the spur gear 35B, the shaft 34B, the electromagnetic clutch 36B, the shaft 37B, the spur gear 38B, and the spur gear 39 are driven. As a result, the transfer roll 23 rotates. Accordingly, the stage 28A can be moved and the transfer roll 23 can be rotated by the molding servo motor 31A, and the stage 28B can be moved and the transfer roll 23 can be rotated by the molding servo motor 31B.

  In the above, the pinion gears 32A and 32B, the shafts 34A and 34B, the spur gears 35A and 35B, the electromagnetic clutches 36A and 36B, the shafts 37A and 37B, the spur gears 38A and 38B, and the spur gear 39 are formed by the forming servo motors 31A and 31B. A power transmission mechanism for rotation that transmits the driving force to the transfer roll 23 is configured. The forming servo motors 31 </ b> A and 31 </ b> B and the rotation power transmission mechanism constitute rotating means for rotating the transfer roll 23.

  Further, the pinion gears 32A and 32B, the rack gears 33A and 33B, the stage bases 26A and 26B, and the guide rails 27A and 27B are movable power transmission mechanisms that transmit the driving force of the forming servo motors 31A and 31B to the stages 28A and 28B. It is composed. The forming servomotors 31A and 31B and the moving power transmission mechanism constitute moving means for moving the stages 28A and 28B in the direction in which the uneven portion 9 is formed with respect to the transfer roll 23.

  Next, a molding process for forming the uneven portion 9 on the light incident end surface 7a of the light guide plate 7 using the optical sheet processing apparatus 20 configured as described above will be described with reference to FIG. In the main forming step, two workers are arranged on the front side and the rear side of the optical sheet processing apparatus 20. That is, work is performed by a total of four workers. At this time, the transfer roll 23 is heated to a certain temperature (for example, 100 ° C. to 200 ° C.) by the induction coil 41 and the power supply unit 42.

  First, in the state where both the stage 28A on which the molded light guide plate 7 is placed and the stage 28B on which the light guide plate 7 before molding is placed are located on the front side of the optical sheet processing apparatus 20, the molding servo motor 31B. Is rotated in a predetermined direction to turn on the electromagnetic clutch 36B. The driving of the molding servo motor 31A is stopped, and the electromagnetic clutch 36A is OFF.

  Then, as shown in FIG. 10A, the stage 28B moves to the rear side while the transfer roll 23 rotates counterclockwise. At this time, a constant pressure (for example, 0.05 MPa to 50 MPa) is applied to the stage 28B so that the light incident end surface 7a of the light guide plate 7 placed on the stage 28B is pressed against the transfer surface 23a of the transfer roll 23 by the pressing cylinder 30B. Apply. As a result, the transfer uneven portion 19 of the transfer roll 23 is transferred to the light incident end surface 7a of the light guide plate 7 placed on the stage 28B. While the light guide plate 7 placed on the stage 28B is being molded in this way, the molded light guide plate 7 is taken out from the stage 28A.

  Next, the driving of the molding servo motor 31B is stopped, and the electromagnetic clutch 35B is turned off. Then, as shown in FIG. 10B, the rotation of the transfer roll 23 stops, and the stage 28B on which the molded light guide plate 7 is placed stops on the rear side of the optical sheet processing apparatus 20. In the meantime, a new light guide plate 7 is placed and placed on the stage 28A.

  Next, the stage 28A on which the new light guide plate 7 is placed is located on the front side of the optical sheet processing apparatus 20, and the stage 28B on which the molded light guide plate 7 is placed is located on the rear side of the optical sheet processing apparatus 20. In this state, the molding servo motor 31A is rotationally driven in a predetermined direction, and the electromagnetic clutch 36A is turned on.

  Then, as shown in FIG. 10C, the stage 28A moves rearward while the transfer roll 23 rotates clockwise. At this time, a constant pressure is applied to the stage 28A by the pressing cylinder 30A so that the light incident end surface 7a of the light guide plate 7 placed on the stage 28A is pressed against the transfer surface 23a of the transfer roll 23. As a result, the transfer uneven portion 19 of the transfer roll 23 is transferred to the light incident end surface 7a of the light guide plate 7 placed on the stage 28A. While the light guide plate 7 placed on the stage 28A is being molded in this way, the molded light guide plate 7 is taken out from the stage 28B.

  Next, the drive of the molding servo motor 31A is stopped, and the electromagnetic clutch 36A is turned OFF. Then, as shown in FIG. 10 (d), the rotation of the transfer roll 23 stops and the stage 28 A on which the molded light guide plate 7 is placed stops on the rear side of the optical sheet processing apparatus 20. Meanwhile, a new light guide plate 7 is placed and placed on the stage 28B.

  Next, in a state where both the stage 28A on which the molded light guide plate 7 is placed and the stage 28B on which the new light guide plate 7 is placed are located on the rear side of the optical sheet processing apparatus 20, the molding servo motor 31B. Is rotated in the opposite direction to turn on the electromagnetic clutch 36B.

  Then, as shown in FIG. 10E, the stage 28B moves forward while the transfer roll 23 rotates in the clockwise direction. At this time, a constant pressure is applied to the stage 28B by the pressing cylinder 30B so as to press the light incident end surface 7a of the light guide plate 7 placed on the stage 28B against the transfer surface 23a of the transfer roll 23. As a result, the transfer uneven portion 19 of the transfer roll 23 is transferred to the light incident end surface 7a of the light guide plate 7 placed on the stage 28B. While the light guide plate 7 placed on the stage 28B is being molded in this way, the molded light guide plate 7 is taken out from the stage 28A.

  Next, driving of the molding servo motor 31B is stopped, and the electromagnetic clutch 36B is turned OFF. Then, as shown in FIG. 10 (f), the rotation of the transfer roll 23 stops and the stage 28 B on which the molded light guide plate 7 is placed stops at the front side of the optical sheet processing apparatus 20. In the meantime, a new light guide plate 7 is placed and placed on the stage 28A.

  Next, the stage 28A on which the new light guide plate 7 is placed is located on the rear side of the optical sheet processing apparatus 20, and the stage 28B on which the molded light guide plate 7 is placed is located on the front side of the optical sheet processing apparatus 20. In this state, the molding servo motor 31A is rotationally driven in the opposite direction to turn on the electromagnetic clutch 36A.

  Then, although illustration is omitted, the stage 28A moves forward while the transfer roll 23 rotates counterclockwise. At this time, a constant pressure is applied to the stage 28A by the pressing cylinder 30A so that the light incident end surface 7a of the light guide plate 7 placed on the stage 28A is pressed against the transfer surface 23a of the transfer roll 23. As a result, the transfer uneven portion 19 of the transfer roll 23 is transferred to the light incident end surface 7a of the light guide plate 7 placed on the stage 28A. While the light guide plate 7 placed on the stage 28A is being molded in this way, the molded light guide plate 7 is taken out from the stage 28B.

  Next, when the drive of the forming servo motor 31A is stopped and the electromagnetic clutch 36A is turned off, the rotation of the transfer roll 23 is stopped, and the stage 28A on which the light guide plate 7 that has been formed is mounted is provided on the optical sheet processing apparatus 20. Stop at the front side. Meanwhile, a new light guide plate 7 is placed and placed on the stage 28B.

  In this way, in the main forming step, while the molded light guide plate 7 placed on the stage 28A is taken out and a new light guide plate 7 is put on the stage 28A, it is placed on the stage 28B. An uneven portion 9 is formed on the light incident end surface 7a of the placed light guide plate 7, the molded light guide plate 7 placed on the stage 28B is taken out, and a new light guide plate 7 is placed on the stage 28B. During the process, the uneven portion 9 can be formed on the light incident end surface 7a of the light guide plate 7 placed on the stage 28A. Moreover, in this shaping | molding process, it can shape | mold from both front and back directions about any light-guide plate 7 mounted on stage 28A, 28B.

  Another molding process for forming the concavo-convex portion 9 on the light incident end surface 7a of the light guide plate 7 using the optical sheet processing apparatus 20 will be described with reference to FIG. In the main forming step, one worker is arranged on each of the front side and the rear side of the optical sheet processing apparatus 20. That is, work is performed by a total of two workers. At this time, the transfer roll 23 is heated to a constant temperature by the induction coil 41 and the power supply unit 42.

  First, the stage 28A on which the molded light guide plate 7 is placed is located on the rear side of the optical sheet processing apparatus 20, and the stage 28B on which the light guide plate 7 before molding is placed is located on the front side of the optical sheet processing apparatus 20. In this state, the molding servo motor 31B is rotated in a predetermined direction to turn on the electromagnetic clutch 36B. The driving of the molding servo motor 31A is stopped, and the electromagnetic clutch 36A is OFF.

  Then, as shown in FIG. 11A, the stage 28B moves rearward while the transfer roll 23 rotates counterclockwise. At this time, a constant pressure is applied to the stage 28B by the pressing cylinder 30B so as to press the light incident end surface 7a of the light guide plate 7 placed on the stage 28B against the transfer surface 23a of the transfer roll 23. As a result, the transfer uneven portion 19 of the transfer roll 23 is transferred to the light incident end surface 7a of the light guide plate 7 placed on the stage 28B. While the light guide plate 7 placed on the stage 28B is being molded in this way, the molded light guide plate 7 is taken out from the stage 28A.

  Next, driving of the molding servo motor 31B is stopped, and the electromagnetic clutch 36B is turned OFF. Then, as shown in FIG. 11B, the rotation of the transfer roll 23 stops and the stage 28B on which the molded light guide plate 7 is placed stops on the rear side of the optical sheet processing apparatus 20. In the meantime, a new light guide plate 7 is placed and placed on the stage 28A.

  Next, the electromagnetic clutch 36B is turned off while the stage 28A on which the new light guide plate 7 is placed and the stage 28B on which the molded light guide plate 7 is placed are located on the rear side of the optical sheet processing apparatus 20. The molding servo motor 31B is rotationally driven in the opposite direction with the same. Then, as shown in FIG. 11C, the stage 28B on which the molded light guide plate 7 is placed moves forward while the rotation of the transfer roll 23 is stopped. At this time, no pressure is applied to the stage 28B by the pressing cylinder 30B. When the stage 28B returns to the original position, the molding servo motor 31B is stopped. Meanwhile, the stage 28A on which the new light guide plate 7 is placed stands by at the same position.

  Next, the stage 28A on which the new light guide plate 7 is placed is located on the rear side of the optical sheet processing apparatus 20, and the stage 28B on which the molded light guide plate 7 is placed is located on the front side of the optical sheet processing apparatus 20. In this state, the molding servo motor 31A is rotationally driven in a predetermined direction, and the electromagnetic clutch 36A is turned on.

  Then, as shown in FIG. 11D, the stage 28A moves forward while the transfer roll 23 rotates counterclockwise. At this time, a constant pressure is applied to the stage 28A by the pressing cylinder 30A so that the light incident end surface 7a of the light guide plate 7 placed on the stage 28A is pressed against the transfer surface 23a of the transfer roll 23. As a result, the transfer uneven portion 19 of the transfer roll 23 is transferred to the light incident end surface 7a of the light guide plate 7 placed on the stage 28A. While the light guide plate 7 placed on the stage 28A is being molded in this way, the molded light guide plate 7 is taken out from the stage 28B.

  Next, the drive of the molding servo motor 31A is stopped, and the electromagnetic clutch 36A is turned OFF. Then, as shown in FIG. 11 (e), the rotation of the transfer roll 23 stops and the stage 28 A on which the molded light guide plate 7 is placed stops at the front side of the optical sheet processing apparatus 20. Meanwhile, a new light guide plate 7 is placed and placed on the stage 28B.

  Next, the electromagnetic clutch 36A is turned off in a state where both the stage 28A on which the molded light guide plate 7 is placed and the stage 28B on which the new light guide plate 7 is placed are located on the front side of the optical sheet processing apparatus 20. As it is, the molding servo motor 31A is driven to rotate in the opposite direction. Then, as shown in FIG. 11F, the stage 28A on which the molded light guide plate 7 is placed moves to the rear side while the rotation of the transfer roll 23 is stopped. At this time, no pressure is applied to the stage 28A by the pressing cylinder 30A. When the stage 28A returns to the original position, the molding servo motor 31A is stopped. In the meantime, the stage 28B on which the new light guide plate 7 is placed stands by at the same position.

  As described above, also in the main forming step, while the molded light guide plate 7 placed on the stage 28A is taken out and a new light guide plate 7 is put on the stage 28A, the light guide plate 7 is placed on the stage 28B. An uneven portion 9 is formed on the light incident end surface 7a of the placed light guide plate 7, the molded light guide plate 7 placed on the stage 28B is taken out, and a new light guide plate 7 is placed on the stage 28B. During the process, the uneven portion 9 can be formed on the light incident end surface 7a of the light guide plate 7 placed on the stage 28A. Further, in the main forming step, the light guide plate 7 can be formed by the minimum required number of workers.

  With reference to FIG. 12, still another molding process for forming the uneven portion 9 on the light incident end surface 7 a of the light guide plate 7 using the optical sheet processing apparatus 20 described above will be described. In the main forming step, two workers W are arranged on the front side of the optical sheet processing apparatus 20 (see FIG. 4). At this time, the transfer roll 23 is heated to a constant temperature by the induction coil 41 and the power supply unit 42.

  First, in the state where both the stage 28A on which the molded light guide plate 7 is placed and the stage 28B on which the light guide plate 7 before molding is placed are located on the front side of the optical sheet processing apparatus 20, the molding servo motor 31B. Is rotated in a predetermined direction to turn on the electromagnetic clutch 36B. The driving of the molding servo motor 31A is stopped, and the electromagnetic clutch 36A is OFF.

  Then, as shown in FIG. 12A, the stage 28B moves rearward while the transfer roll 23 rotates counterclockwise. At this time, a constant pressure is applied to the stage 28B by the pressing cylinder 30B so as to press the light incident end surface 7a of the light guide plate 7 placed on the stage 28B against the transfer surface 23a of the transfer roll 23. As a result, the transfer uneven portion 19 of the transfer roll 23 is transferred to the light incident end surface 7a of the light guide plate 7 placed on the stage 28B. While the light guide plate 7 placed on the stage 28B is being molded in this way, the molded light guide plate 7 is taken out from the stage 28A.

  Next, driving of the molding servo motor 31B is stopped, and the electromagnetic clutch 36B is turned OFF. Then, as shown in FIG. 12B, the rotation of the transfer roll 23 stops, and the stage 28B on which the molded light guide plate 7 is placed stops on the rear side of the optical sheet processing apparatus 20. In the meantime, a new light guide plate 7 is placed and placed on the stage 28A.

  Next, the stage 28A on which the new light guide plate 7 is placed is located on the front side of the optical sheet processing apparatus 20, and the stage 28B on which the molded light guide plate 7 is placed is located on the rear side of the optical sheet processing apparatus 20. In this state, the molding servo motor 31B is rotated in the opposite direction while the electromagnetic clutch 36B is turned off. Then, as shown in FIG. 12C, the stage 28B on which the molded light guide plate 7 is placed moves forward while the rotation of the transfer roll 23 is stopped. At this time, no pressure is applied to the stage 28B by the pressing cylinder 30B. When the stage 28B returns to the original position, the driving of the molding servo motor 31B is stopped. Meanwhile, the stage 28A on which the new light guide plate 7 is placed stands by at the same position.

  Next, with the stage 28A on which the new light guide plate 7 is placed and the stage 28B on which the molded light guide plate 7 is placed positioned on the front side of the optical sheet processing apparatus 20, the molding servo motor 31A is operated. The electromagnetic clutch 36A is turned ON by rotating in a predetermined direction.

  Then, as shown in FIG. 12D, the stage 28A moves to the rear side while the transfer roll 23 rotates in the clockwise direction. At this time, a constant pressure is applied to the stage 28A by the pressing cylinder 30A so that the light incident end surface 7a of the light guide plate 7 placed on the stage 28A is pressed against the transfer surface 23a of the transfer roll 23. As a result, the transfer uneven portion 19 of the transfer roll 23 is transferred to the light incident end surface 7a of the light guide plate 7 placed on the stage 28A. While the light guide plate 7 placed on the stage 28A is being molded in this way, the molded light guide plate 7 is taken out from the stage 28B.

  Next, the drive of the molding servo motor 31A is stopped, and the electromagnetic clutch 36A is turned OFF. Then, as shown in FIG. 12 (e), the rotation of the transfer roll 23 stops and the stage 28 A on which the molded light guide plate 7 is placed stops on the rear side of the optical sheet processing apparatus 20. Meanwhile, a new light guide plate 7 is placed and placed on the stage 28B.

  Next, the stage 28A on which the molded light guide plate 7 is placed is located on the rear side of the optical sheet processing apparatus 20, and the stage 28B on which the new light guide plate 7 is placed is located on the front side of the optical sheet processing apparatus 20. In the state where the electromagnetic clutch 36A is OFF, the molding servo motor 31A is rotated in the opposite direction.

  Then, as shown in FIG. 12F, the stage 28A on which the molded light guide plate 7 is placed moves forward while the rotation of the transfer roll 23 is stopped. At this time, no pressure is applied to the stage 28A by the pressing cylinder 30A. When the stage 28A returns to the original position, the driving of the molding servo motor 31A is stopped. Meanwhile, the stage 28B on which the new light guide plate 7 is placed stands by at the same position.

  As described above, also in the main forming step, while the molded light guide plate 7 placed on the stage 28A is taken out and a new light guide plate 7 is put on the stage 28A, the light guide plate 7 is placed on the stage 28B. An uneven portion 9 is formed on the light incident end surface 7a of the placed light guide plate 7, the molded light guide plate 7 placed on the stage 28B is taken out, and a new light guide plate 7 is placed on the stage 28B. During the process, the uneven portion 9 can be formed on the light incident end surface 7a of the light guide plate 7 placed on the stage 28A. Further, in this molding process, even if there is a layout problem such as a wall on the rear side of the optical sheet processing apparatus 20, the molding operation of the light guide plate 7 is performed by a minimum required number of workers. Can do.

  The moving speed of the stages 28A and 28B is not always constant. For example, when the plurality of LEDs 6 are arranged facing the light incident end surface 7 a of the light guide plate 7, the uneven portion 9 may be formed only on the light incident end surface 7 a around the LED 6. For this reason, when the transfer surface 23a of the transfer roll 23 and the light incident end surface 7a of the light guide plate 7 are pressed against each other, when the light incident end surface 7a at the position facing the LED 6 and the transfer surface 23a are in contact with each other, a desired uneven portion 9 is formed. When the stages 28A and 28B are moved at the transfer (molding) speed obtained, and the other light incident end surface 7a and the transfer surface 23a are in contact with each other, the stages 28A and 28B may be moved at a higher speed. Thereby, the processing tact of the light guide plate 7 can be improved. The light incident end surface 7a around the LED 6 indicates +1 mm from the width size of the LED 6 in the direction orthogonal to the thickness direction of the light guide plate 7.

  As described above, in the present embodiment, the transfer roll 23 is heated and the transfer surface 23 a of the transfer roll 23 and the light incident end surface 7 a of the light guide plate 7 are pressed against each other to be provided on the transfer surface 23 a of the transfer roll 23. The uneven portion for transfer 19 is thermally transferred to the light incident end surface 7a of the light guide plate 7 so that the uneven portion 9 is formed on the light incident end surface 7a of the light guide plate 7. Chips are not generated unlike the case where the uneven portion 9 is formed on the light incident end surface 7a of the light guide plate 7. Accordingly, the chips are not attached to or mixed into the light guide plate 7, and the product quality can be stabilized.

  By the way, when there is only one stage on which the light guide plate 7 is placed, the molding process of the light guide plate 7 must be interrupted during the period in which the light guide plate 7 is put in the stage and the period in which the light guide plate 7 is taken out from the stage. I do not get. Accordingly, the tact time of the light guide plate 7 is reduced.

  On the other hand, in this embodiment, the two stages 28A and 28B on which the light guide plate 7 is placed are arranged so as to sandwich the transfer roll 23, and the light guide plate 7 placed on the stage 28A is not molded. During the period, the light guide plate 7 placed on the stage 28B is molded, and during the period when the light guide plate 7 placed on the stage 28B is not molded, the light guide plate 7 placed on the stage 28A is molded. Make the molding process. Since the light guide plate 7 is formed from both the left and right sides of the transfer roll 23 in this way, the light guide plate 7 is inserted into the stages 28A and 28B and the light guide plate 7 is taken out of the stages 28A and 28B. There is no need to interrupt the molding process. Thereby, the forming tact of the light guide plate 7 can be increased and the productivity can be improved.

  The present invention is not limited to the above embodiment. For example, the mechanism for rotating the transfer roll 23 and moving the stages 28A and 28B in the front-rear direction (Y direction) of the apparatus is not limited to that described above. The structure shown in FIG. In the structure shown in FIG. 13, the electromagnetic clutch 36A intermittently connects the output shaft 31a of the forming servo motor 31A and the shaft 37A fixed to the spur gear 38A. Further, the electromagnetic clutch 36B intermittently connects the output shaft 31a of the molding servo motor 31B and the shaft 37B fixed to the spur gear 38B.

  In addition to the meshing of the spur gears, for example, a belt and a pulley may be used as a mechanism for rotating the transfer roll 23.

  In the above embodiment, the transfer roll 23 is rotated by the forming servo motors 31A and 31B and the stages 28A and 28B are moved in the Y direction. However, the present invention is not limited to this, and means for rotating the transfer roll 23 is not limited thereto. Further, as means for moving the stages 28A and 28B, different motors may be used, and the motors may be driven synchronously.

  Here, when the light guide plate 7 and the transfer roll 23 are in contact with each other, if the rotational speed of the transfer roll 23 and the moving speed of the stages 28A and 28B are greatly shifted, the appearance of the light guide plate 7 is deteriorated. To do. For this reason, when the motor dedicated to the roll for rotating the transfer roll 23 is not installed, the diameter management of the transfer roll 23 is important. On the other hand, when a dedicated motor for rotating the transfer roll 23 is installed, the rotation speed of the motor can be adjusted in accordance with the diameter of the transfer roll 23. Can be prevented.

  Further, in the above embodiment, the light guide plate 7 supported on the other of the stages 28A and 28B is molded while the light guide plate 7 supported on one of the stages 28A and 28B is not molded. However, if possible, the light guide plates 7 supported by the stages 28A and 28B may be simultaneously molded.

  In the above embodiment, one light guide plate 7 is supported on the stages 28A and 28B. However, the number of light guide plates 7 supported on the stages 28A and 28B is not limited to one, and a plurality of light guide plates 7 may be provided. There may be.

  Furthermore, although the said embodiment forms the uneven | corrugated | grooved part 9 in the light-incidence end surface 7a of the light-guide plate 7 comprised in the backlight unit 3 of the liquid crystal display device 1 used for a liquid crystal television, the optical of this invention The sheet processing apparatus and method can be applied to, for example, an optical sheet forming process as a light guide plate for illumination or decoration.

DESCRIPTION OF SYMBOLS 7 ... Light guide plate (optical sheet), 7a ... Light-incidence end surface, 9 ... Uneven portion, 19 ... Uneven portion for transfer, 20 ... Optical sheet processing apparatus, 23 ... Transfer roll, 23a ... Outer peripheral surface (transfer surface), 23b ... Roll shaft, 26A, 26B ... stage base (moving power transmission mechanism, moving means), 27A, 27B ... guide rail (moving power transmission mechanism, moving means), 28A, 28B ... stage, 30A, 30B ... pressing cylinder ( Pressure application means), 31A, 31B ... molding servo motor (rotation means, movement means), 32A, 32B ... pinion gear (rotation power transmission mechanism, rotation means, movement power transmission mechanism, movement means), 33A, 33B ... rack gear (moving power transmission mechanism, moving means), 34A, 34B ... shaft (rotating power transmission mechanism, rotating means), 35A, 35B ... spur gear (rotating power transmission) Structure, rotation means), 36A, 36B ... electromagnetic clutch (rotation power transmission mechanism, rotation means), 37A, 37B ... shaft (rotation power transmission mechanism, rotation means), 38A, 38B ... spur gear (second spur gear) , Rotation power transmission mechanism, rotation means), 39: spur gear (first spur gear, rotation power transmission mechanism, rotation means), 41: induction coil (heating means), 42: power supply (heating means).

Claims (7)

An optical sheet processing apparatus for forming an uneven portion on a light incident end face of an optical sheet made of a thermoplastic resin,
A metal transfer roll having a transfer surface for imparting the concavo-convex portion to the light incident end surface of the optical sheet;
A pair of stages arranged to sandwich the transfer roll and supporting the optical sheet;
Heating means for heating the transfer roll;
Pressure applying means for applying pressure to the stage so as to press the transfer surface and the light incident end surfaces;
A rotating means for rotating the transfer roll;
An optical sheet processing apparatus comprising: a moving unit configured to move the stage in the forming direction of the uneven portion with respect to the transfer roll. The rotating means includes a pair of motors provided corresponding to the stages, and a rotational power transmission mechanism that transmits a driving force of the motors to the transfer roll.
The optical sheet processing apparatus according to claim 1, wherein the moving unit includes the pair of motors and a moving power transmission mechanism that transmits a driving force of the motors to the stages. The rotation power transmission mechanism includes a first spur gear attached to a roll shaft of the transfer roll, a pair of second spur gears that mesh with the first spur gear, and the second spur gear to the second spur gear. A pair of clutches for intermittently transmitting and receiving the driving force of each motor,
The power transmission mechanism for movement includes a pair of racks provided on each stage, and a pair of pinions attached to output shafts of the motors and meshing with the racks, respectively. The optical sheet processing apparatus according to claim 2. An optical sheet processing method for forming a concavo-convex portion on a light incident end face of an optical sheet made of a thermoplastic resin,
A preparation step of preparing the optical sheet processing apparatus according to any one of claims 1 to 3,
While heating the transfer roll and applying pressure to the stage so as to press the transfer surface and the light incident end surfaces, the stage is moved with respect to the transfer roll while rotating the transfer roll. Forming the concavo-convex part on the light incident end surface by moving in the forming direction of the part,
In the molding step, the optical sheet supported on the other of the pair of stages is not formed on the light incident end face of the optical sheet supported on one of the pair of stages. An optical sheet processing method, wherein the uneven portion is formed on a light incident end surface. The molding step includes
While taking out the optical sheet with respect to the one stage, the other stage is moved from one side to the other side, and the unevenness is formed on the light incident end surface of the optical sheet supported by the other stage. A first step of forming a portion;
After performing the first step, while the optical sheet is being taken out from the other stage, the one stage is moved from the one side to the other side and supported by the one stage. A second step of forming the concavo-convex portion on the light incident end face of the optical sheet;
After performing the second step, while taking out the optical sheet from the one stage, the other stage is moved from the other side to the one side and is supported by the other stage. A third step of forming the uneven portion on the light incident end surface of the optical sheet;
After performing the third step, while the optical sheet is being taken out from the other stage, the one stage is moved from the other side to the one side and supported by the one stage. The optical sheet processing method according to claim 4, further comprising: a fourth step of forming the uneven portion on the light incident end face of the optical sheet. The molding step includes
While taking out the optical sheet with respect to the one stage, the other stage is moved from one side to the other side, and the unevenness is formed on the light incident end surface of the optical sheet supported by the other stage. A first step of forming a portion;
A second step of moving the other stage from the other side to the one side while the one stage is waiting after performing the first step;
After performing the second step, while taking out the optical sheet from the other stage, the one stage is moved from the other side to the one side and supported by the one stage. A third step of forming the uneven portion on the light incident end surface of the optical sheet;
5. A fourth step of moving the one stage from the one side to the other side while the other stage is waiting after the third step is performed. The optical sheet processing method as described. The molding step includes
While taking out the optical sheet with respect to the one stage, the other stage is moved from one side to the other side, and the unevenness is formed on the light incident end surface of the optical sheet supported by the other stage. A first step of forming a portion;
A second step of moving the other stage from the other side to the one side while the one stage is waiting after performing the first step;
After performing the second step, while the optical sheet is being taken out from the other stage, the one stage is moved from the one side to the other side and supported by the one stage. A third step of forming the uneven portion on the light incident end surface of the optical sheet;
5. A fourth step of moving the one stage from the other side to the one side while the other stage is waiting after the third step is performed. The optical sheet processing method as described.

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