Abstract:
Recording devices with adjustable and lockable recording medium width guides, and support mechanisms for adjustable and lockable recording medium width guides are disclosed. A recording device includes a pair of recording medium width guides that control the widthwise position of a recording medium upon discharge from the recording device. A support mechanism supports the width guides and can lock the position of the width guides. The support mechanism includes a pair of sliding members individually coupled with one of the width guides, and a pressure member that clamps the sliding members together at a position where the sliding members overlap. The pressure member is configurable to clamp the sliding members together, and to unclamp the sliding members.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     Priority is claimed under 35 U.S.C. §119 to Japanese Application No. 2009-019198, filed on Jan. 30, 2009 which is hereby incorporated by reference in its entirety. 
     BACKGROUND 
     1. Technical Field 
     The present invention relates to a recording device that records images on a recording medium, and to a support mechanism for side guide members in the recording device. 
     2. Related Art 
     Recording devices for recording images on a recording medium according to the related art typically have guides that guide the recording medium as it is conveyed. Recording devices in which the guides are movable and can be adjusted to the width of the recording medium are also known from the literature. See, for example, Japanese Unexamined Patent Appl. Pub. JP-A-2004-161443. 
     The recording device taught in JP-A-2004-161443 can convey the recording medium in a stable, consistent manner by using guides adjusted (by moving the guides) to the size of the recording medium. If, however, the guides can be moved too easily, they may cease to function properly as guides and may actually interfere with the transportation of the recording media. Accidental movement of the guides may be particularly problematic. Such accidental movement may result from contact with some object or from the user&#39;s hand bumping the guides when the guides are exposed outside the recording device. Accordingly, a configuration that can positively lock the position of the guides is desirable, especially where the guides can be easily locked. 
     SUMMARY 
     The following presents a simplified summary of some embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented later. 
     Recording devices having adjustable and lockable side guide members to guide a recording medium, and a support mechanism for adjustable and lockable side guide members in a recording device are provided. The side guide members are supported by a mechanism that enables easy adjustment of the side guide members to the size of the recording medium, as well as easy locking of the side guide members in the adjusted position. 
     Thus, in first aspect, a recording device is provided that records on a recording medium and discharges the recording medium from a discharge exit in a discharge direction. The recording device includes a guide member having a guide surface that supports the recording medium after discharge from the discharge exit, a pair of side guide members that restrict a position of the recording medium relative to the guide surface traverse to the discharge direction, and a support mechanism that supports the pair of side guide members relative to the guide surface. The support mechanism is operable to position the side guide members traverse to the discharge direction and lock the pair of side guide members in a desired position. The support mechanism includes a pair of overlapping sliding members and a pressure member. Each of the sliding members is coupled with one of the side guide members and configured to move relative to the guide surface traverse to the discharge direction. The pressure member is configurable to clamp the sliding members together at a position where the pair of sliding members overlap to lock the side guide members in position. And the pressure member is configurable to unclamp the sliding members by displacing an operating part of the pressure member. In many embodiments, the guide member includes a recess, and the operating part of the pressure member is disposed in the recess when the guide member are locked in position. 
     In many embodiments, the above-described recording device provides significant functionality. For example, the guides can be adjusted and then locked in a specific position. And the side guide members can be released from being locked by operating a pressure member that is exposed from a recessed part of the guide surface. Because the position of the pair of side guide members that control the position of the width of the recording medium can thus be locked with a simple operation, and can be unlocked and moved as needed, the side guide members can be easily adjusted to the width of the recording medium used. In addition, because pressure is applied to the overlapping sliding members so that they cannot slide, the side guide members can be positively locked with high precision and with no chatter. 
     In many embodiments, each of the sliding members includes a panel part extending traverse to the discharge direction. And the panel parts can overlap side by side. And one of the panel parts can include a protrusion facing the panel part of the other sliding member. 
     When pressure is applied to the sliding members at a position where the pair of sliding members overlap, the sliding members are held firmly by the pressure transferred through the protrusion. As a result, the side guide members can be locked positively by the simple operation of moving the pressure member. 
     In many embodiments, the recording device includes a spring member coupled with the pressure member to generate pressure pushing the panel parts of the mutually overlapping sliding members in contact with each other to clamp the sliding members together. 
     Because the sliding members are clamped together using the elasticity of a flat spring, the side guide members can be reliably locked, the pressure applied to the sliding members can be controlled within a suitable range so that the load on the sliding members can be controlled. As a result, a longer service life for the sliding members may be achieved, and the strength required in the sliding members may be reduced, thereby reducing size and cost. 
     In many embodiments, the pair of sliding members slide symmetrically relative to a centerline of the guide surface. In many embodiments, the support mechanism includes a gear mounted to rotate about an axis traverse to the discharge direction, and each of the sliding members includes gear teeth engaged with the gear. Such symmetrical movement serves to limit the position of the recording medium traverse to the discharge direction. 
     In many embodiments, the recording device includes a pair of internal side guide members that restrict a position of the recording medium inside a case of the recording device traverse to the discharge direction. And both the internal side guide members and the side guide members constrain side edges of the recording medium so that the recording medium is centered in a transportation path for the recording medium. The addition of the internal side guide members may serve to convey the recording medium smoothly because the widthwise position of the recording medium is aligned with the center of the transportation path inside the recording device and on the guide surface at the discharge exit. 
     In another aspect, a mechanism is provided for supporting a pair of recording medium side guide members in a recording device that records on a recording medium and discharges the recording medium from a discharge exit in a discharge direction. The support mechanism includes a pair of overlapping sliding members and a pressure member. Each sliding member is coupled with one of the side guide members and coupled with the recording device to move traverse to the discharge direction. The pressure member is operable to clamp the sliding members together at a position where the pair of sliding members overlap to lock the side guide members in position, and to unclamp the sliding members by displacing an operating part of the pressure member. The support mechanism is operable to position the side guide members traverse to the discharge direction and lock the pair of side guide members in a desired position. In many embodiments, the operating part of the pressure member is disposed in a recess of the printer when the side guide members are locked in position. 
     The support mechanism can have one, more, or all of the above described features, functions, and/or advantages of the above-described recording device. Because the disclosed recording devices and support mechanisms enable the positions of side guide members that control the position of a recording medium discharged from the discharge exit to be locked with a simple operation, and to be unlocked and moved as needed, the side guide members can be easily adjusted to the width of the recording medium used. 
     Other objects and attainments together with a fuller understanding of the invention will become apparent and appreciated by referring to the following description and claims taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an oblique view of an inkjet printer in accordance with many embodiments. 
         FIG. 2  is a section view of the inkjet printer of  FIG. 1 . 
         FIG. 3  is an oblique view of the inkjet printer of  FIG. 1  with a roll paper compartment cover open. 
         FIGS. 4 and 5  are enlarged plan views of main parts near the paper exit of the printer of  FIG. 1 . 
         FIG. 6  shows the configuration of the support mechanism of the paper width guide of the printer of  FIG. 1 . 
         FIG. 7  is an oblique view of main parts in the configuration of the paper width guide support mechanism of the printer of  FIG. 1 . 
         FIG. 8  is a section view of main parts near the paper exit of the printer of  FIG. 1 . 
         FIG. 9  is a section view of main parts in the configuration of the paper width guide support mechanism of the printer of  FIG. 1 . 
         FIG. 10  is a section view of main parts near the paper exit of the printer of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, various embodiments of the present invention will be described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the embodiments. However, the present invention can be practiced without the specific details. Furthermore, well-known features may be omitted or simplified in order not to obscure the embodiment being described. 
     Referring now to the drawings, in which like reference numerals represent like parts throughout the several views,  FIG. 1  shows an inkjet printer  1  in accordance with embodiments.  FIG. 2  shows a section view of the inkjet printer  1 . Note that in  FIG. 2  the transportation path P of the roll paper  100  is indicated by an imaginary (dashed) line. 
     The inkjet printer  1  (referred to as simply “printer  1 ” below) uses roll paper  100  as the recording medium, and prints (records) images, including text, by discharging and depositing ink on the surface of the roll paper  100 . The roll paper  100  is a sheet of paper or plastic, for example, wound into a roll. 
     The sheet used in the roll paper  100  can have a plastic coating on the sheet surface, or label paper having label stock with an adhesive coating on the back carried on a web liner. In many embodiments, the roll paper  100  used in the printer  1  is label paper. 
     The printer  1  records an image on the roll paper  100 , and then discharges the printed paper from a paper exit  25  located in the front of the printer  1 . A cutter unit  80  ( FIG. 2 ) is disposed before the paper exit  25  in the printer  1 . The cutter unit  80  cuts the roll paper  100  to a specified length, and the portion that is cut off is discharged from the paper exit  25 . The printer  1  can therefore print and output labels made by cutting the label paper to a specified length. 
     As shown in  FIG. 1 , the printer  1  has a basically box-shaped case  10 . The top of the case  10  is covered by a top panel  11 . Side panels  12  are disposed on the left and right sides of the case  10 . And a back panel  14  ( FIG. 2 ) is disposed to the back of the case  10  perpendicularly to a surface on which the printer  1  is placed. 
     A back top panel  15  is disposed connecting the top and back surfaces at the top back end of the case  10 . A front top panel  13  is disposed at the top front part of the case  10 . An ink cartridge loading door  16  and a roll paper cover  20  are disposed side by side below the front top panel  13 . 
     The ink cartridge loading door  16  can open and close relative to the case  10  via a hinge (not shown in the figure) at the bottom end thereof. A storage unit in which an ink cartridge (not shown in the figure) is held is located inside the ink cartridge loading door  16 . Ink cartridges can be loaded and removed by opening the ink cartridge loading door  16 . A catch  17  that a user can grasp when opening and closing the door is disposed at the top of the ink cartridge loading door  16 . And a transparent window  18  is disposed in the bottom part of the ink cartridge loading door  16  for checking if an ink cartridge is loaded. 
     The roll paper cover  20  (access cover) opens and closes by pivoting forward at the bottom end thereof. When the roll paper cover  20  is open, a roll paper compartment  10   a , which is a space used as a recording medium storage unit for storing the roll paper  100  inside the printer  1 , is exposed (see  FIG. 2 ). And the roll paper  100  can be loaded and replaced from the front of the printer  1 . 
     The paper exit  25  is located at the top part of the roll paper cover  20  at a place between the roll paper cover  20  and the front top panel  13 . The paper exit  25  is a horizontally oriented narrow opening configured to accommodate the width of the roll paper  100 . An exit paper guide  26  (guide member) connected to the bottom end of the paper exit  25  is coupled with the roll paper cover  20 . The exit paper guide  26  has a slope (guide surface) that supports the roll paper  100  discharged from the paper exit  25  from below. A pair of paper width guides  27   a ,  27   b  (side guide members) are positioned at the top end of the guide surface to guide the roll paper  100  from opposite sides of the paper width. The paper width guides  27   a ,  27   b  restrict and guide the position of the width of the roll paper  100  in the exit paper guide  26 . 
     A discharge tray unit  30  (external member) that receives the roll paper  100  descending along the exit paper guide  26  is disposed below the exit paper guide  26 . 
     The discharge tray unit  30  includes a discharge tray  31  forming part of a receiving unit  32  in which the roll paper  100  is stored at a position below the exit paper guide  26 , and a sliding member  41  that is slidably attached to the discharge tray  31 . Engaging pins  35  (a hinge) are coupled with the top part of the discharge tray  31 , and these engaging pins  35  engage bearings (not shown in the figure) coupled with the roll paper cover  20 . The discharge tray unit  30  is thus attached so that it can pivot freely on the engaging pins  35  relative to the front of the roll paper cover  20 . 
     The receiving unit  32  of the discharge tray  31  is the space defined by a downward slope (similar to the exit paper guide  26 ), a pair of side walls  33  rising from opposite sides of this slope, and a paper stop  42 . The paper stop  42  is coupled with the bottom end of the sliding member  41 . and prevents the roll paper  100  from falling out of the receiving unit  32 . By sliding the sliding member  41  on the discharge tray  31 , the paper stop  42  can be moved to change the length of the receiving unit  32 . 
     As described above, a portion of the roll paper  100  cut-off by the cutter unit  80  is discharged from the paper exit  25 . The cut-off portion moves down along the slope of the exit paper guide  26 , and drops into the receiving unit  32 . In some circumstances, the cut-off portion of the roll paper  100  may have a tendency to turn when it drops into the receiving unit  32  from the bottom end of the slope of the exit paper guide  26 . Advantageously, by adjusting the length of the receiving unit  32  to a suitable length, the cut-off portions of the roll paper  100  can collect in the receiving unit  32  without turning over. Because the cut-off portions of the roll paper  100  do not turn over and are left with the side having the printed image facing up, the printed image can be checked as the cut-off portions accumulate in the receiving unit  32 . 
     As shown in  FIG. 2 , when the sliding member  41  is slid all the way in to the case  10 , the distal end  43   a  of the sliding member  41  touches the front of the roll paper cover  20 . When the sliding member  41  is pulled forward from the discharge tray  31 , the distal end  43   a  moves away from the front of the roll paper cover  20 , and the printer-side slope  36  of the discharge tray  31  touches the front of the roll paper cover  20 . 
     The angle of the paper collection surface  34  to the installation surface (e.g., horizontal surface of a desktop supporting the printer) of the printer  1  is small when the distal end  43   a  is touching the roll paper cover  20 , and is slightly greater when the printer-side slope  36  is touching the roll paper cover  20 . 
     More specifically, when the paper stop  42  is positioned at the top (as illustrated in  FIG. 2 ), the distal end  43   a  contacts the roll paper cover  20 , and the angle of the paper collection surface  34  is small. This position is suitable for receiving the roll paper  100  cut-offs when they are cut to a short length. Because the paper stop  42  is close to the paper exit  25  and the angle of the paper collection surface  34  is small, the roll paper  100  cut-offs are less likely turn over or fall out of the receiving unit  32 . 
     When the sliding member  41  is pulled down, the distal end  43   a  separates from the roll paper cover  20  and the angle of the paper collection surface  34  becomes steeper. This position is suitable for receiving long cut-offs of roll paper  100  because the receiving unit  32  is correspondingly long. Because the angle of the paper collection surface  34  is steep, long cut-off portions are less likely to jam up near the paper exit  25  and may more reliably drop to the position of the paper stop  42 . 
     The discharge tray unit  30  is thus configured so that the angle of the paper collection surface  34  changes automatically as a result of sliding the sliding member  41  to change the length of the receiving unit  32 . 
     The bottom end of the roll paper cover  20  is supported so that it can pivot relative to the case  10  of the printer  1  on a hinge unit  23  ( FIG. 2 ), and can open so that the front of the roll paper cover  20  rotates facing down. The roll paper cover  20  is held in the closed position by a locking mechanism (not shown). When a release lever  22  disposed at the top end of the roll paper cover  20  is operated, the lock mechanism is released and the roll paper cover  20  can be opened. 
     As shown in  FIG. 2 , the case  10  of the printer  1  has a frame including a bottom frame  51 , a back frame  52 , and a top frame  53 . The bottom frame  51  is a frame panel that supports the bottom part of the printer  1 . A plurality of feet  54  that contact the installation surface are affixed to the bottom frame  51 . The back frame  52  rises from the bottom frame  51 . The top frame  53  is affixed to the top part of the back frame  52 . A control circuit board  55 , on which various control circuits and devices that control the printer  1  are disposed, is supported on the back side of the back frame  52 . 
     The roll paper compartment  10   a  (in which the roll paper  100  is stored) is a space reserved between the bottom frame  51  and the top frame  53 . A roll paper support roller  61  and a roll paper support bar  62  are disposed at the bottom of the roll paper compartment  10   a.    
     The roll paper support roller  61  is disposed freely rotatably to the frame of the case  10 , and together with the roll paper support bar  62  supports the roll paper  100  from the bottom so that the roll paper  100  can rotate easily. Roll paper pressers  63  that contact the sides of the roll paper  100  and stabilize the roll paper  100  are disposed on the left and right sides of the roll paper compartment  10   a.    
     The roll paper support bar  62  is supported by a pair of roll paper guides  62   a  (internal side guide members). The roll paper guides  62   a  are disposed on the left and right sides in the roll paper compartment  10   a , and can move along the roll paper support bar  62  to match the width of the roll paper  100 . The roll paper guides  62   a  limit the position of the width of the roll paper  100  relative to the center of the width of the transportation path P, and enable stable conveyance of the roll paper  100 . 
     A first transportation roller  64  and a second transportation roller  65  are disposed in opposition at the top part of the roll paper compartment  10   a , and convey the roll paper  100  that is pulled up therebetween. The first transportation roller  64  is driven by a transportation motor (not shown in the figure), and the second transportation roller  65  is a follower that follows the rotation of the first transportation roller  64 . 
     A paper guide  69  that redirects the roll paper  100  to the front is disposed above the first transportation roller  64  and second transportation roller  65 . A third transportation roller  66  is disposed opposite the paper guide  69 . The third transportation roller  66  is driven by the transportation motor (not shown in the figure) noted above, and conveys the roll paper  100  forward. 
     A paper support unit  60  is disposed in front of the paper guide  69 . The paper support unit  60  is supported by the top frame  53 , and includes components that execute recording an image on the roll paper  100  and discharging the paper from the paper exit  25 . 
     The paper support unit  60  includes a fourth transportation roller  67  and a fifth transportation roller  68  for transporting the roll paper  100  that is conveyed forward by the third transportation roller  66 , a platen  71  that supports the roll paper  100  from below, a recording head  70  that discharges ink to and records images on the roll paper  100  from above the platen  71 , and the cutter unit  80  that cuts the roll paper  100  on which is an image has been recorded by the recording head  70 . 
     The fourth transportation roller  67  is positioned above the transportation path P. And the fifth transportation roller  68  is disposed below the transportation path P of the roll paper  100  so that the rollers are in opposition. The fifth transportation roller  68  is driven by the foregoing transportation motor (not shown in the figure). And the fourth transportation roller  67  is a follower roller that follows the fifth transportation roller  68 . 
     A guide shaft  72  that extends widthwise to the case  10  is disposed above the fourth transportation roller  67  and fifth transportation roller  68 . The recording head  70  travels on the guide shaft  72  bidirectionally across the width of the roll paper  100  when a head drive motor (not shown in the figure) is operated. 
     The recording head  70  is normally at a standby position adjacent the ink cartridge loading door  16  ( FIG. 1 ) side when not printing, and is denoted by an imaginary line (dashed line) in  FIG. 2 . 
     The recording head  70  is an inkjet recording head that discharges ink onto the surface of the roll paper  100  to record images. More specifically, ink supplied through an ink supply tube  73  from an ink cartridge (not shown in the figure) stored behind the ink cartridge loading door  16  is discharged onto the roll paper  100  from nozzles by means of a discharge mechanism using a piezoelectric device, for example. 
     The roll paper  100  passing between the recording head  70  and platen  71  is conveyed forward through the transportation path P by the transportation force of the fourth transportation roller  67  and fifth transportation roller  68  to the cutter unit  80 . 
     The cutter unit  80  includes a fixed knife  81  that is disposed inset below the transportation path P, and a movable knife  82  that is disposed above the transportation path P to slide against the fixed knife  81 . The roll paper  100  is disposed between the fixed knife  81  and movable knife  82 , which cut through both the label stock and the liner of the roll paper  100 . 
     A cutter drive motor  83  and a cutter drive roller  84  that causes the movable knife  82  to move up and down using the torque of the cutter drive motor  83  are coupled with the movable knife  82 . And the roll paper  100  is cut by the operation of the cutter drive motor  83  and the cutter drive roller  84 . 
     When the roll paper  100  is cut by the cutter unit  80  and the leading end of the roll paper  100  is outside the paper exit  25 , gravity causes the cut-off portion of the cut roll paper  100  to drop onto the exit paper guide  26 . 
     The control circuits mounted on the control circuit board  55  drive the transportation motor (not shown in the figure), the head drive motor (not shown in the figure), the discharge mechanism of the recording head  70 , and the cutter drive motor  83  of the printer  1 , and control the operating sequences related to conveying the roll paper  100 , recording images on the roll paper  100 , and cutting the roll paper  100 . 
     In addition, as shown in  FIG. 1 , a power switch  91  for turning the power of the printer  1  on and off is disposed below the ink cartridge loading door  16 . A cut button  92  for cutting the roll paper  100  by means of the cutter unit  80  ( FIG. 2 ), and a feed button  93  for advancing the roll paper  100  a desired length, are located on the front top panel  13 . 
     The control circuit mounted on the control circuit board  55  starts operating when the power switch  91  is operated and the power turns on, exchanges data and control signals with a host computer, for example, externally connected to the printer  1 , and records images on the roll paper  100  as controlled by the host computer. 
     When the cut button  92  is operated, the control circuit operates the cutter drive motor  83  separately from cutting operations controlled by the host computer. When the feed button  93  is operated, the control circuit operates the transportation motor (not shown in the figure) for as long as the feed button  93  is held depressed separately from paper feed operations controlled by the host computer. 
     An indicator  94  such as shown in  FIG. 1  is also disposed at the front of the printer  1 . The indicator  94  includes a plurality of LEDs. And the control circuit mounted on the control circuit board  55  displays and outputs various messages, such as the operating status of the printer  1  and ink cartridge and replacement prompts, by changing the illumination state of the LEDs of the indicator  94  to light steady, blink, or turn off appropriately. 
       FIG. 3  is an oblique view of the printer  1  with the roll paper cover  20  open. 
     When the release lever  22  is operated and the lock is released, the roll paper cover  20  of the printer  1  pivots forward on the bottom end thereof and opens as shown in  FIG. 3 . When open as shown in  FIG. 3 , the second transportation roller  65 , the fifth transportation roller  68 , the paper guide  69 , and the platen  71  move forward with the roll paper cover  20 , and the roll paper compartment  10   a  is exposed. 
     To load the roll paper  100 , the roll paper  100  is inserted into the roll paper compartment  10   a  that is open as shown in  FIG. 3 , the leading end of the roll paper  100  is pulled out and placed on the fifth transportation roller  68  and platen  71 , and the roll paper cover  20  is then closed. 
     When the roll paper cover  20  closes, the roll paper  100  is held between the platen  71  and the recording head  70 , between the fifth transportation roller  68  and the fourth transportation roller  67 , between the paper guide  69  and the third transportation roller  66 , and between the second transportation roller  65  and the first transportation roller  64 . The roll paper  100  can thus be easily loaded in the transportation path P of the printer  1  shown in  FIG. 2  by simply inserting the roll paper  100  with a leader pulled out into the roll paper compartment  10   a , and then closing the roll paper cover  20 . 
     Because the roll paper cover  20  pivots and drops forward when opened as shown in  FIG. 3 , the discharge tray unit  30  coupled with the roll paper cover  20  contacts the installation surface of the printer  1 . Note that the discharge tray unit  30  pivots easily even after contacting the installation surface of the printer  1  so that there is no interference with opening the roll paper cover  20 . 
       FIG. 4  and  FIG. 5  are enlarged plan views of the area near the paper exit  25 . 
     As described above, a pair of left and right paper width guides  27   a ,  27   b  are coupled with the exit paper guide  26 . And both the paper width guide  27   a  and the paper width guide  27   b  can move widthwise to the roll paper  100  relative to the exit paper guide  26 . Channels  28  configured to accommodate the movement of the paper width guides  27   a ,  27   b  extend in the sloped surface of the exit paper guide  26  across the width of the roll paper  100 . 
     A paper guide plate  29  is disposed to the exit paper guide  26  bridging the channel  28  between the pair of paper width guides  27   a ,  27   b . The roll paper  100  is discharged on top of the paper guide plate  29 . 
     The paper width guides  27   a ,  27   b  can be moved relative to the exit paper guide  26  to adjust to the width of the roll paper  100 , and can be moved to the side ends of the exit paper guide  26  as shown in  FIG. 4 , or to the middle as shown in  FIG. 5 . 
     The paper width guides  27   a ,  27   b  are supported to move symmetrically left and right by the operation of a support mechanism housed inside the exit paper guide  26 . When one of the paper width guides  27   a ,  27   b  is moved, the other also moves in conjunction therewith. 
       FIG. 6  shows the configuration of the support mechanism of the paper width guides  27   a ,  27   b , and is a view of the exit paper guide  26  from below (the back side).  FIG. 7  is an oblique view showing the main parts of the support mechanism for the paper width guides  27   a ,  27   b . And  FIG. 8  is a section view showing the main parts of the support mechanism near the paper exit  25 . In  FIG. 7  and  FIG. 8  the paper width guides  27   a ,  27   b  are not locked. 
     As shown in  FIG. 6  to  FIG. 8 , a frame  212  and a base  211  that is attached to the frame  212  and supports the bottom part of the exit paper guide  26  are disposed to the paper exit  25  inside the exit paper guide  26 , which provides the guide surface that guides the roll paper  100 . 
     The frame  212  is fastened by screws  213  to the frame of the case  10  rendering the paper support unit  60  ( FIG. 2 ), and the frame  212  supports the exit paper guide  26 . 
     As shown in  FIG. 6  and  FIG. 7 , a sliding member  220  that supports the paper width guide  27   a , and a sliding member  230  that supports the paper width guide  27   b , are housed inside the exit paper guide  26 . 
     The sliding member  220  has an arm  222  and a wall part  223  that extend parallel to each other along the width of the roll paper  100 . The arm  222  is a flat member that is parallel to the slope of the exit paper guide  26 , and has a rack  221  formed on one long side. The wall part  223  is a panel member that is vertically oriented when the printer  1  is set for use. 
     The sliding member  230  has an arm  232  and a wall part  233  that extend parallel to each other along the width of the roll paper  100 . The arm  232  is a flat member that is parallel to the slope of the exit paper guide  26 , and has a rack  231  formed on one long side. The wall part  233  is a panel member that is vertically oriented when the printer  1  is set for use. 
     As shown in  FIG. 6 , the sliding member  220  is linked to the paper width guide  27   a  through coupling units  226  and  227 . The one coupling unit  226  passes through the top channel  28 , and connects the paper width guide  27   a  positioned on the front side of the exit paper guide  26  with the sliding member  220  positioned inside the exit paper guide  26 . The other coupling unit  227  passes through the bottom channel  28 , and couples the paper width guide  27   a  and the sliding member  220 . The sliding member  220  is thus connected in unison with the paper width guide  27   a  via couplings that pass through the channel  28  in the exit paper guide  26  and can move freely along the channel  28  in the exit paper guide  26 . 
     The sliding member  230  is linked to the paper width guide  27   b  through coupling units  236  and  237 . The coupling unit  236  passes through the top channel  28  and connects the paper width guide  27   b  with the sliding member  230 . The other coupling unit  237  passes through the bottom channel  28  and couples the paper width guide  27   b  with the sliding member  230 . The sliding member  230  is thus connected in unison with the paper width guide  27   b  via couplings that pass through the channel  28  in the exit paper guide  26  and can move freely along the channel  28  in the exit paper guide  26 . 
     As shown in  FIG. 7 , the arm  222  is positioned below the arm  232 . And the rack  221  and the rack  231  are formed so that they are facing each other. A middle gear  240  is disposed between the arm  222  and the arm  232 . 
     The middle gear  240  is fastened by a screw  242  ( FIG. 6 ,  FIG. 8 ) to the back side of the exit paper guide  26  so that the middle gear  240  can rotate freely. A gear  241  is formed around the circumference of the middle gear  240 . And the gear  241  is meshed with the racks  221  and  231 . 
     As described above, the sliding members  220  and  230  can move along the channels  28 , and the middle gear  240  turns when the sliding members  220  and  230  move. In addition, when one of the sliding members  220  and  230  moves, the other sliding member is moved in the opposite direction via the middle gear  240 . 
     For example, when the paper width guide  27   a  is moved from the position shown in  FIG. 7  to the center of the exit paper guide  26 , the sliding member  220  moves with the paper width guide  27   a , and the middle gear  240  turns. The direction of rotation for this movement is clockwise as seen in  FIG. 7 . As the middle gear  240  turns, the other rack  231  meshed with the gear  241  is driven and the other sliding member  230  moves to the right as seen in  FIG. 7 . More particularly, when one paper width guide  27   a  is moved toward the middle gear  240 , the other paper width guide  27   b  also moves in conjunction therewith toward the middle gear  240 . The opposite is similar. That is, when the one paper width guide  27   a  is moved away from the middle gear  240 , the other paper width guide  27   b  also moves away from the middle gear  240 . Yet further, when paper width guide  27   b  is moved, paper width guide  27   a  also moves in conjunction therewith. 
     As described above, when one of the paper width guides  27   a ,  27   b  is moved, the other guide also moves in conjunction therewith, and the paper width guides  27   a ,  27   b  move left and right symmetrically relative to the middle gear  240 . As a result, by moving the paper width guides  27   a ,  27   b  to match the width of the roll paper  100 , the position of the roll paper  100  is limited by the paper width guides  27   a ,  27   b  to a position in the middle of the width of the exit paper guide  26 , and the center of the width of the roll paper  100  is always over the center (that is, the position of the screw  242 ) of the exit paper guide  26 . 
     As shown in  FIG. 7  and  FIG. 8 , a flat spring  260  is disposed passing through the frame  212  in the center of the width of the exit paper guide  26 . A pressure member  250  is supported by this flat spring  260 . In many embodiments, the flat spring  260  is made by bending steel sheet with the desired elasticity into the desired shape. In many embodiments, the flat spring  260  has an approximately U-shaped configuration when seen in section, including a flat part  261  formed to a horizontal surface, a support part  262  that rises from one end of this flat part  261 , and an engaging part  263  that rises from the other end. 
     The flat part  261  is disposed along the bottom of the frame  212  at a position below the frame  212 , and the support part  262  and engaging part  263  extend upward passing through the bottom of the frame  212 . 
     The wall part  223  and the wall part  233  are disposed overlapping each other as panel units between the support part  262  and the engaging part  263  on top of the bottom of the frame  212 . The wall part  223  faces the support part  262 , and the wall part  233  overlaps the wall part  223 . 
     A flat pressure spring  255  that contacts and applies pressure to the wall part  233  is also disposed between the support part  262  and the engaging part  263 . The pressure spring  255  is a flat spring that is bent into a basic V-shape, and is disposed with the end part touching one side of the wall part  233 . The pressure spring  255  is displaced in conjunction with operating the pressure member  250  as described below, and pushes the wall part  233  toward the wall part  223 . 
     The pressure member  250  is disposed in the center of the width of the exit paper guide  26 . And the pressure member  250  has an engaging part  251  that is fit between the engaging part  263  and the pressure spring  255 , and an operating part  252  (operating unit) that protrudes below the exit paper guide  26 . 
     The engaging part  251  is fit between the pressure spring  255  and a recessed part formed in the engaging part  263 , and is supported to pivot in this space. The pressure member  250  and the engaging part  251  can pivot relative to the engaging part  263 . 
     The support mechanism of the paper width guides  27   a ,  27   b  thus includes the frame  212 , the sliding members  220  and  230  coupled to the paper width guides  27   a ,  27   b , a middle gear  240 , a pressure member  250 , and a flat spring  260 . The coupling units  226 ,  227 ,  236 ,  237 , coil springs  228  and  238 , and the base  211  can also be included in the support mechanism. 
       FIG. 9  is an oblique view showing the main components of the support mechanism for the paper width guides  27   a ,  27   b .  FIG. 10  is a section view of the main components of the support mechanism near the paper exit  25 .  FIG. 9  and  FIG. 10  show the paper width guides  27   a ,  27   b  when secured so that they do not move. 
     When the pressure member  250  is turned clockwise from the position shown in  FIG. 8 , the engaging part  251  goes to a substantially horizontal position as shown in  FIG. 10 . And the wall part  233  is pushed against the wall part  223  by the pressure spring  255 . And the wall part  233  and the wall part  223  are pushed against the support part  262  by the pressure spring  255 , and are thus prevented from sliding easily. 
     A top rib  234  and a bottom rib  235  are formed on a side surface of the wall part  223  as protrusions extending along the length of the wall part  233 . 
     A top rib  224  and a bottom rib  225  are formed on a side surface of the wall part  223  as protrusions extending along the length of the wall part  223 . 
     As a result, when the pressure spring  255  is displaced and presses against the wall part  233 , the wall parts  233 ,  223  and the support part  262  are pressed together through the intervening top ribs  234 ,  224  and bottom ribs  235 ,  225 . Friction is increased by concentrating pressure at the ribs And the wall part  233  and wall part  223  are secured so that they do not slide along the channels  28 . 
     More specifically, in the position shown in  FIG. 9  and  FIG. 10 , the sliding members  220  and  230  are locked so that they do not slide. 
     When the sliding members  220  and  230  are locked as shown in  FIG. 9  and  FIG. 10 , the operating part  252  of the pressure member  250  enters a recessed part  26   a  formed in the center of the width of the exit paper guide  26 . Because the recessed part  26   a  is exposed at the front of the printer  1  as shown in  FIG. 4 , the operating part  252  can be operated to apply pressure by means of a jig that can enter the recessed part  26   a.    
     When the operating part  252  is pushed down from the position shown in  FIG. 9  and  FIG. 10 , the pressure member  250  pivots on the engaging part  263  and returns to the position shown in  FIG. 7  and  FIG. 8 . In this position the pressure from the pressure spring  255  is released, and the sliding member  220  and sliding member  230  can slide. 
     In order to operate the operating part  252  again to lock the sliding members  220  and  230 , the operating part  252  can be simply pushed up. Because the operating part  252  protrudes below the exit paper guide  26  when the sliding members  220  and  230  are unlocked as shown in  FIG. 8 , pushing the operating part  252  up is simple. 
     As described above, the printer  1  is a printer  1  that records images on and discharges roll paper  100  from a paper exit  25 . The printer  1  has an exit paper guide  26  that guides roll paper  100  discharged from the paper exit  25 ; a pair of paper width guides  27   a ,  27   b  that restrict the widthwise position of the roll paper  100  on the exit paper guide  26 ; and a support mechanism that supports the paper width guides  27   a ,  27   b  movably widthwise to the roll paper  100  and secures the paper width guides  27   a ,  27   b  in a desired position. The support mechanism has a pair of sliding members  220  and  230  that slide in conjunction with the pair of paper width guides  27   a ,  27   b ; and a pressure member  250  that applies pressure to the wall parts  223 ,  233  at a position where the wall parts  223 ,  233  of the pair of sliding members  220  and  230  overlap. A recessed part  26   a  is rendered in the exit paper guide  26 . And the operating part  252  of the pressure member  250  is exposed from this recessed part  26   a . When the pressure member  250  is displaced by operating the operating part  252 , the paper width guides  27   a ,  27   b  are released from being locked by the support mechanism. 
     As a result, the paper width guides  27   a ,  27   b  can be unlocked by operating the operating part  252  of the pressure member  250  exposed from the recessed part  26   a.    
     Because the position of the paper width guides  27   a ,  27   b  can thus be locked by a simple operation, and the paper width guides  27   a ,  27   b  can be unlocked and moved, the paper width guides  27   a ,  27   b  can be easily adjusted to the width of the roll paper  100  used. 
     Furthermore, because the operating part  252  can be easily operated from the recessed part  26   a , but cannot be easily moved without a tool or jig that can enter the recessed part  26   a , the person using the printer  1  will not accidentally operate the operating part  252  and unlock the sliding members  220  and  230 . A configuration that enables easily releasing the lock as needed but prevents the lock from being accidentally released, and is therefore particularly convenient, can thus be achieved. 
     As shown in  FIG. 3 , the configuration of printer  1  thus enables easily loading and replacing roll paper  100  by simply opening the roll paper cover  20  and inserting the roll paper  100 , and can reliably control the position of the roll paper  100  widthwise. The roll paper  100  can thus be prevented from becoming skewed, and the label paper can be consistently conveyed, printed, and output. 
     Furthermore, because the sliding members  220  and  230  are locked in position by friction as a result of applying pressure to the wall parts  223 ,  233  by means of a pressure spring  255  at a position where the wall parts  223 ,  233  overlap, the sliding members  220  and  230  can be reliably locked with high precision. 
     For example, while securing and preventing the sliding members  220  and  230  from moving by restricting rotation of the middle gear  240  is also conceivable, backlash corresponding to the play in the meshing gears may occur, and the paper width guides  27   a ,  27   b  may move from their positions they held when the middle gear  240  was restricted. Chattering commensurate to the play in the gears may also result. 
     However, because the sliding members  220  and  230  are locked in the position at which the pressure member  250  is operated so that the two wall parts  223 ,  233  are pressed together and secured by friction as described above, the paper width guides  27   a ,  27   b  can be positioned and locked with high precision in the desired position without being affected by any gear teeth backlash. 
     Furthermore, because the wall parts  223 ,  233  of the sliding members  220  and  230  overlap side by side in the discharge direction of the roll paper  100 , and top ribs  224 ,  234  and bottom ribs  225 ,  235  are rendered on the wall parts  223 ,  233 , strong friction is produced between the sliding members  220  and  230  by the pressure transferred through the pressure member  250 , and the paper width guides  27   a ,  27   b  can be reliably locked. 
     Yet further, when the pressure member  250  is turned and the sliding members  220  and  230  locked, the wall parts  223 ,  233  are locked by the elastic force working between the support part  262  and the engaging part  263  of the flat spring  260 . More specifically, when the pressure member  250  rotates, the engaging part  251  works to expand the gap between the engaging part  263  and the wall part  233 , and presses the wall parts  233 ,  223  to the support part  262  side. As a result, the engaging part  251  and wall parts  223 ,  233  are secured between the support part  262  and the engaging part  263 . The sliding members  220  and  230  are therefore positively locked, the paper width guides  27   a ,  27   b  can be locked, the pressure applied to the sliding members  220  and  230  can be controlled to a suitable level, and the load on the sliding members  220  and  230  can be controlled within a suitable range. 
     Furthermore, because the engaging part  251  contacts the wall part  233  through the pressure spring  255 , the sudden application of force to the wall parts  233 ,  223  is buffered by the flexibility of the pressure spring  255 . A longer service life can therefore be achieved in the sliding members  220  and  230 , the strength required in the sliding members  220  and  230  can be reduced, and size and cost can be reduced. 
     Furthermore, because the pair of sliding members  220  and  230  slide symmetrically to the center of the exit paper guide  26 , the paper width guides  27   a ,  27   b  can be secured and released with a simple operation. 
     Yet further, because the widthwise position of the roll paper  100  is restricted so that the widthwise position of the roll paper  100  is aligned with the center of the transportation path P, the roll paper  100  can be conveyed smoothly. Yet further, because the roll paper guide  62   a  positions the roll paper  100  to the center of the transportation path P inside the case  10 , the roll paper  100  can be conveyed even more smoothly. 
     A preferred embodiment of the invention is described above, but the invention is not limited to the foregoing embodiment. For example, a configuration in which an exit paper guide  26  is attached to the paper exit  25  disposed to the front of the printer  1 , and the paper width guides  27   a ,  27   b  are disposed slidably on the inclined surface of this exit paper guide  26 , is described in the foregoing embodiment of the invention, but the invention is not so limited, and a configuration in which the paper exit  25  is rendered in the top of the printer  1 , and the paper width guides  27   a ,  27   b  that guide the roll paper  100  discharged from the paper exit  25  are disposed to the top or the front of the printer  1 , is also conceivable. 
     In addition, a configuration in which the sliding members  220  and  230  that support the paper width guides  27   a ,  27   b  are disposed on the back side of the exit paper guide  26  is described by way of example above, but the invention is not so limited. For example, a configuration in which the paper width guides  27   a ,  27   b  are supported by sliding members exposed on top of the exit paper guide  26  is also conceivable. 
     Yet further, a configuration in which the wall part  223  of the sliding member  220  and the wall part  233  of the sliding member  230  disposed vertically on the back side of the exit paper guide  26  are secured by the pressure spring  255  is described in the foregoing embodiment, but the wall parts  223 ,  233  can be disposed horizontally and locked in position by pressured applied to the wall parts  223 ,  233  from above or below. 
     The above embodiment of the invention is described using a roll of label paper as the recording medium by way of example, but the recording medium is not limited to label paper, and other types of cut sheet media and continuous media may be used. The recording medium may also be an optical disc medium such as CD or DVD media. 
     A printer  1  that discharges ink to record images is used by way of example as the recording device, but the invention can also be applied to other types of printers, including thermal printers that record images on thermal paper using a thermal head, dot impact printers, and dye sublimation printers. The invention can also be used in other types of electronic devices having such a printer as a component part. 
     Although the present invention has been described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims.