Patent Publication Number: US-7586509-B2

Title: Thermal transfer printer ribbon cassette apparatus and ribbon cassette mounting method

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a thermal transfer printer ribbon cassette apparatus and a ribbon cassette mounting method, and more particularly to a thermal transfer printer ribbon cassette apparatus and a ribbon cassette mounting method by which the mounting operation of a ribbon cassette main body to a printer main body is simple and reliable. 
   2. Description of the Prior Art 
   Thermal transfer ribbons loaded in conventional thermal transfer printers are thin. As a result, snaking and wrinkling thereof readily occurs as they are supplied to the transport path and during winding from the transport path. Accordingly, stable transport of wide thermal transfer ribbons in particular is afforded by a system as described, for example, in Japanese Unexamined Patent Application No. 2006-82297. Rather than the thermal transfer ribbon being set on ribbon shafts (supply spindle and winding spindle) provided in the printer main body, the thermal transfer ribbon is loaded in advance in a ribbon cassette which is then loaded in the printer main body. 
   However, there are problems inherent in the loading of a ribbon cassette of this type in a printer, in that it causes a further demand for simplifying the attachment operation to shorten the ribbon replacement time and for simplification of the operation for loading the thermal transfer ribbon into the ribbon cassette. 
   There are problems inherent in the use of a thermal transfer printer and so on in assembly with various types of peripheral apparatus (for example label affixing apparatus), in factories or manufacturing sites in particular, in that, as a consequence of the need for the thermal transfer ribbon to be loaded in large rolls of large diameter (for example, 1000 m winding or the like) and due to the increased weight thereof, better operability and convenience of the mounting operation of the ribbon cassette is desirable. 
   A further problem arises if the thermal transfer printer is installed in a narrow space from the viewpoint of the difficulty of the attachment operation of the ribbon cassette. 
   An additional problem arises if the thermal transfer printer itself is three-dimensionally installed in a range of positions from the viewpoint of the need to further simplify the implementation of the attachment operation of the ribbon cassette. 
   More specifically, there is a problem from the viewpoint of the need for a simple and reliable mounting operation based on a simple guide mechanism when, as an initial stage mounting operation, the ribbon cassette is moved toward the thermal transfer printer. 
   The mounting of the ribbon cassette in the thermal transfer printer requires that the thermal head and the platen roller of a printing unit of the printer be established in a mutually separated state and, following the mounting of the ribbon cassette, requires that the thermal head and the platen roller be again closed in a predetermined pressed state and, in addition, requires that the ribbon cassette eventually be fixed in the printer. From the viewpoint of convenience of the operation, the separate implementation of the approach/separate operation of the thermal head and the platen roller and the final mounting and fixing operation of the ribbon cassette on the thermal transfer printer should be avoided. In this respect as well, there is a need for improved convenience of the operations. 
   Furthermore, when the thermal transfer ribbon is used in the form of a large roll of increased weight, this raises the possibility that thermal transfer ribbon mounted in the ribbon cassette will fall from each of the ribbon supply spindle and the ribbon winding spindle through the cassette main body side while they are handled. Accordingly, there is an inherent problem from the viewpoint of a need for simplicity and reliability of the structures for mounting and fixing (inserting) and operations for mounting and fixing (inserting) the ribbon supply spindle and the ribbon winding spindle in the cassette main body. 
   Because the ribbon supply spindle and ribbon winding spindle are mounted in the ribbon cassette side, there is a need for the ribbon supply spindle and ribbon winding spindle rotation drive mechanisms to be linked when the ribbon cassette is mounted and fixed on the printer side. A structure for engaging and disengaging gear mechanisms between the printer and the ribbon cassette is normally used for this purpose. When the ribbon cassette is being mounted on the thermal transfer printer, there is a problem from the viewpoint of a need for the mounting operation to be based on a smooth engagement of these gear mechanisms with each other to enable reliable implementation. 
   There is a further inherent problem from the possibility of increased impact noise being generated during the final mounting of the ribbon cassette on the thermal transfer printer, which accompanies increases in size and weight of the thermal transfer ribbon and ribbon cassette and the need to eliminate this impact noise. 
   In addition, there is a further inherent problem from increased vibration generated in the thermal transfer printer main body associated with the transport and printing of the thermal transfer ribbon and print sheet and accompanying increases in size and weight of the thermal transfer ribbon and ribbon cassette and the unwanted unavoidable effects thereof on the printing of the printing sheet and transport thereof in the thermal transfer printer. 
   SUMMARY OF THE INVENTION 
   With the foregoing problems in mind, it is an object of the present invention to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which the operations for loading and replacement of the thermal transfer ribbon can be implemented easily. 
   A further object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which the loading processing and the replacement processing are possible in a short time. 
   Another object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which both the operation for loading of the ribbon in the ribbon cassette itself and the operation for loading the cassette itself in the printer main body can be efficiently implemented. 
   Another object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which a ribbon cassette comprising a large roll thermal transfer ribbon in particular is able to be simply and reliably mounted in the thermal transfer printer side. 
   Another object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which, if the thermal transfer printer is installed in a narrow space, or if the thermal transfer printer itself is three-dimensionally installed in a range of positions, the insert-attach operation of the ribbon cassette is able to be executed even more simply. 
   Another object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which a simple and reliable mounting operation based on a simple guide mechanism is possible when, as an initial stage mounting operation, the ribbon cassette is moved toward the thermal transfer printer. 
   Another object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which the approach/separate operation of the thermal head and platen roller in the thermal transfer printer and final mounting and fixing operation of the ribbon cassette on the thermal transfer printer is able to be implemented in a simple operation. 
   Another object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which the possibility of the thermal transfer ribbon falling from each of the ribbon supply spindle and ribbon winding spindle through the cassette main body side is avoided, and the simplicity and reliability of the structures for mounting and fixing (inserting-removing) the ribbon supply spindle and the ribbon winding spindle on the cassette main body and the operations for the mounting and fixing (inserting-removing) thereof can be ensured. 
   Another object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which during mounting of the ribbon cassette in the thermal transfer printer, the gear mechanisms can be smoothly engaged with each other. 
   Another object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which there is a possibility of reducing the impact noise generated during the final mounting of the ribbon cassette on the thermal transfer printer. 
   Another object of the present invention is to provide a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting in which unwanted effects due to vibration generated in the thermal transfer printer as a whole are prevented from extending to the printing of the printing sheet and transport thereof in the thermal transfer printer. 
   The present invention focuses on a three-stage guide structure and engagement structure such that as a cassette main body is moved toward a printer main body for mounting therein, a main guide shaft that protrudes in a comparatively long length from the printer main body side in the cassette main body direction is used as an initial guide providing guidability along a level and comparatively wide printer main body stay. Finally, there is engageability of a final positioning engagement pin of high positioning precision formed in the printer main body stay and a final position engagement hole formed in a handle-side base plate. 
   A first invention comprises a thermal transfer printer ribbon cassette apparatus releasably attached to a thermal transfer printer which comprises a printer main body wherein a thermal head and a platen roller are mounted and where a printing sheet and a thermal transfer ribbon are held between the thermal head and the platen roller and are transported, and which performs printing on the printing sheet. It further comprises a cassette main body formed by a printer-side base plate that extends along a direction of transport of the printing sheet and the thermal transfer ribbon and that opposes a cassette attachment face of the printer main body. A handle-side base plate opposes the printer-side base plate. The handle-side base plate comprises handles for an attachment/detachment operation. A support shaft fixes the handle-side base plate and the printer-side base plate with a gap not less than the width of the thermal transfer ribbon and the printing sheet. The cassette main body comprises a ribbon supply spindle for supplying the thermal transfer ribbon to a transport path for the thermal transfer ribbon and a ribbon winding spindle for winding the thermal transfer ribbon transported to this transport path. The spindles are able to be releasably disposed between the handle-side base plate and the printer-side base plate. A cassette main body stay is positioned between the handle-side base plate and the printing-side base plate. There is a main guide hole into which a main guide shaft protruding from the printer main body side in the cassette main body direction is removably fit. A guide cut-away part is guidable along the printer main body stay formed from the printer main body side toward the printer-side base plate formed in the printer-side base plate. A final positioning engagement pin is formed in the printer main body stay of the printer main body. A final positioning engagement hole is formed in the handle-side base plate. The cassette main body is releasably attached to in the printer main body by engagement/disengagement of the main guide shaft of the printer main body with and from the main guide hole of the cassette main body stay and by engagement/disengagement of the final positioning engagement pin of the printer main body stay with and from the final positioning engagement hole of the handle-side base plate. 
   A second invention comprises a thermal transfer printer ribbon cassette mounting method for setting the thermal transfer printer ribbon to a thermal transfer printer. That printer comprises a printer main body where a thermal head and a platen roller are mounted and where a printing sheet and a thermal transfer ribbon are held between the thermal head and the platen roller and are transported. This prints on the printing sheet. The method comprises forming a cassette main body by providing a printer-side base plate that extends along a direction of transport of the printing sheet and the thermal transfer ribbon and that opposes a cassette attachment face of the printer main body, forming a handle-side base plate that opposes the printer-side base plate and that comprises handles for an attachment/detachment operation, and providing a support shaft for fixing the handle-side base plate and the printer-side base plate with a gap not less than the width of the thermal transfer ribbon and the printing sheet. The cassette main body is formed to comprise a ribbon supply spindle for supplying the thermal transfer ribbon to a transport path for the thermal transfer ribbon and a ribbon winding spindle for winding the thermal transfer ribbon transported to this transport path that are able to be releasably disposed between the handle-side base plate and the printer-side base plate. A cassette main body stay is positioned between the handle-side base plate and the printing-side base plate in which a main guide hole into which a main guide shaft protruding from the printer main body side in the cassette main body direction is removably fit. A guide cut-away part guidable along the printer main body stay is formed from the printer main body side toward the printer-side base plate in the printer-side base plate. A final positioning engagement pin is formed in the printer main body stay of the printer main body. A final positioning engagement hole is formed in the handle-side base plate. The cassette main body is operated handles to engage the main guide shaft hole of the cassette main body stay with the main guide shaft of the printer main body. The guide cut-away part of the printer-side base plate is moved along the printer main body stay as the cassette main body is moved nearer the cassette attachment face of the printer main body. The final positioning engagement hole of the handle-side base plate is engaged with the final positioning engagement pin of the printer main body stay so that the cassette main body can be attached to or detached from the printer main body. 
   A cover may be mounted in the printer main body, in which an opening is formed in the cassette main body side through which the cassette main body is guidable to the printer main body side. 
   The printer-side base plate comprises an auxiliary engagement pin provided toward the printer main body side. An auxiliary engagement hole is formed in the cassette attachment face of the printer main body in which the assist engagement pin is engageable. 
   A head opening/closing lever for a contact/separation operation of the thermal head and the platen roller and a cassette attachment lever for fixing the cassette main body to the printer main body are connected to be integrally operable. 
   A supply spindle guide groove and a winding spindle guide groove along which the ribbon supply spindle and the ribbon winding spindle respectively are guidable in set directions are formed in the inner-side wall face of the handle-side base plate and the printer-side base plate, respectively. A spindle receiving member able to fix the ribbon supply spindle and the ribbon winding spindle to their respective set positions is provided in the rearmost part of the supply spindle guide groove and the winding spindle guide groove. 
   Driven gears are formed in the printer main body side end parts of each of the ribbon supply spindle and the ribbon winding spindle. The driven gears are engageable with driver gears that face the cassette attachment face of the printer main body. The gear end parts of each of the driven gears and the driver gears are formed in a tapered shape. 
   A magnet is in at least one of the cassette attachment face of the printer main body and a printer main body opposing face opposing the printer main body of the printer-side base plate. The cassette main body is attachable to the printer main body. 
   An elastic member is mounted in an opening edge part of the main guide hole of the cassette main body, toward the cassette attachment face of the printer main body. 
   An end part of the cassette main body stay on the opposing side to the printer main body of the main guide hole can be opened. 
   An end part of the cassette main body stay on the opposing side to the printer main body of the main guide hole can be closed. 
   A lever fixing pin is provided in the vicinity of the platen roller in a base frame of the printer main body. A head opening/closing lever is engaged with or disengaged from the lever fixing pin so that the thermal head is able to be held in a pressed state at a predetermined pressure on the platen roller. The handle-side base plate can to be fixed to the base frame by an auxiliary opening/closing lever in the handle-side base plate in a different position from that of the head opening/closing lever and an auxiliary lever fixing pin in the base frame and by engagement of the assist lever fixing pin and the auxiliary opening-closing lever. 
   In the thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting based on the present invention, because of the provision of a three-stage guide structure and engagement structure that is broadly based on the use of a main guide shaft protruding in a comparatively long length from the printer main body side in the cassette main body direction being as an initial guide and then guidability along a level and comparatively wide printer main body stay and, finally, engageability of a final positioning engagement pin of high positioning precision formed in the printer main body stay and a final position engagement hole formed in a handle-side base plate, even if the width and length of the thermal transfer ribbon is increased with a resultant increase in the size and weight of the ribbon cassette itself, a stable mounting operation in which the cassette main body itself is easily and reliably guided while being pushed in the printer main body direction can be executed by a simple operation based on the holding of handles on the handle-side base plate. 
   According to the first invention in particular, because a main guide shaft, printer main body stay and final positioning engagement hole are provided in the printer main body side and, corresponding thereto, a main guide hole, guide cut-away part and final positioning engagement hole are formed in the cassette main body side, the cassette main body can be easily and reliably mounted in the printer main body by a sequential engagement and guiding thereof. 
   According to the second invention in particular, as the cassette main body is moved nearer to engage with the main guide hole and guide cut-away part and as it uses the main guide shaft and guide cut-away part provided in the printer main body side as a guide, the final positioning engagement pin of the printer main body can be engaged with good positioning precision with the final positioning engagement hole of the cassette main body, and the cassette main body can be easily and reliably and stably mounted to the printer main body. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a printer main body and a ribbon cassette apparatus of a thermal transfer printer according to a first embodiment of the present invention; 
       FIG. 2  is a front view as seen in the direction from the ribbon cassette apparatus to the printer main body of the same; 
       FIG. 3  is a perspective view of the ribbon cassette apparatus as seen in the direction of the printer main body; 
       FIG. 4  is a perspective view of the ribbon cassette apparatus as seen from the printer main body of the same; 
       FIG. 5  is an exploded perspective view of the ribbon cassette apparatus as seen in the direction of the printer main body; 
       FIG. 6  is an exploded perspective view of the ribbon cassette apparatus as seen from the direction of the printer main body; 
       FIG. 7  is a main part perspective view of a cassette main body as seen in the direction of the printer main body in a state in which a thermal transfer ribbon R has not been loaded in the cassette main body; 
       FIG. 8  is a main part perspective view of the cassette main body as seen from the printer main body; 
       FIG. 9  is a main part expanded perspective view of supply spindle driver gear, a winding spindle driver gear and, a supply spindle sensor-side gear and a winding spindle sensor-side gear, all components that face onto a cassette attachment face of the printer main body; 
       FIG. 10  is a main part expanded perspective view of a supply spindle follower gear and winding spindle follower gear components that face onto a printer main body opposing face of the cassette main body (printer-side base plate); 
       FIG. 11  is a main part expanded view of a head opening/shutting lever component; 
       FIG. 12  is a perspective view showing a state in which a cassette attachment lever is operated after the cassette main body (ribbon cassette apparatus) has been inserted into the printer main body; 
       FIG. 13  is a front view of a ribbon cassette apparatus of a second embodiment of the present invention; 
       FIG. 14  is a main part expanded perspective view of a cassette main body stay as seen from the printer main body side in an ribbon cassette apparatus of a third embodiment of the present invention; and 
       FIG. 15  is a main part expanded perspective view of a cassette main body stay as seen from the direction of the printer main body. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention concerns a thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting including a main guide shaft, a printer main body stay and a final positioning engagement hole provided in a printer main body side all being guided to and sequentially engaged with a main guide hole, a guide cut-away part and a final positioning engagement hole respectively formed in a cassette main body side. As a result, the cassette main body can be stably mounted easily and reliably in the printer main body. 
   A thermal transfer printer ribbon cassette apparatus and method of ribbon cassette mounting according to a first embodiment of the present invention are described with reference to  FIG. 1  to  FIG. 12 . 
   To illustrate the relative positional relationships from the side of the respective members,  FIG. 2  has been drawn without consideration of the front-to-rear relationships of each member in the printer main body  2  direction. 
   The thermal transfer printer  1  comprises a printer main body  2 , ribbon cassette apparatus  3 , and cover  4  of a rectangular (U-shaped) cross-section mounted on the printer main body  2 . 
   As shown in  FIG. 1  and  FIG. 5  in particular, the printer main body  2  comprises a cassette attachment face  5  formed from a side frame parallel to the direction of transport of a printing sheet L and thermal transfer ribbon R ( FIG. 2 ), a base frame  6 , main guide shaft  7 , printer main body stay  8 , final positioning face  9 , final positioning engagement pin  10 , thermal head  11 , platen roller  12 , head opening/shutting lever  13  and operating panel  14 .  FIG. 5  and  FIG. 6  have been drawn omitting the cover  4  and the operating panel  14 . 
   The base frame  6  orthogonally intersects with the cassette attachment face  5  and is fixed by a cantilever method so as to be positioned in  FIG. 1  in the lower part of the ribbon cassette apparatus  3 . 
   The main guide shaft  7  protrudes in a comparatively long length from the cassette attachment face  5  in the direction of the ribbon cassette apparatus  3  across the base frame  6 . 
   The printer main body stay  8  has an upper surface that is wide and is a comparatively broad surface area. It is fixed by a cantilever method to orthogonally intersect with the cassette insertion face  5 . 
   The final positioning face  9  is positioned in the side face of the printer main body stay  8 . It is configured from another side frame that orthogonally intersects with the printer main body stay  8 , and it opposes the ribbon cassette apparatus  3 . 
   The final positioning engagement pin  10  protrudes from the final positioning face  9  in the direction of the ribbon cassette apparatus  3  to enable maintaining the high precision of the final mounted position of the ribbon cassette apparatus. 
   The thermal head  11  is turnable in the opening/shutting direction (separating direction and pressing direction with respect to the platen roller  12 ) about a head opening/shutting spindle  15  provided to extend between the cassette attachment face  5  and the final positioning face  9 . 
   In the opened thermal head  11  state, labels, tags or other ribbon-like printing sheet L are loaded between the thermal head  11  and platen roller  12 . A ribbon-like thermal transfer ribbon R is similarly able to be loaded between the thermal head  11  and the platen roller  12  employing a ribbon cassette apparatus  3 . 
   In the closed state of the thermal head  11 , the printing sheet L and the thermal transfer ribbon R are held between the thermal head and the platen roller  12  and are transported along a transport path  16  enabling printing on the printing sheet L. 
   The thermal head  11  is approach/separated opened and shut with respect to the platen roller  12  by the turnable operation of the head opening/shutting lever  13  in the forward and reverse directions around a lever shaft  17  which extends from the cassette attachment face  5  and the final positioning face  9 . The thermal head  11  is able to be pressed onto the platen roller  12  at a predetermined printing pressure. 
   As described later, the head opening/shutting lever  13  is concentric with a section of the lever shaft  17  and is integrally operable with the cassette attachment lever  63  because of a small space (base plate interval  64 , see  FIG. 11 ) provided in the axial direction therebetween. 
   The operating panel  14  comprises a display  18  and operating keys  19  and is used for performing printing and providing various controls on the printer main body  2 . 
   Mounting holes  20  are formed in each of the four corners of the printer main body  2  side in the cassette attachment face  5  and in other positions as needed for facilitating an assembly in which the printer main body  2  (ribbon cassette apparatus  3 ) is able to be connected with predetermined peripheral apparatus (for example label affixing apparatus not shown) at arbitrary positions. 
   As shown in  FIG. 5  and  FIG. 6 , the ribbon cassette apparatus  3  comprises a cassette main body  21 , which comprises a printer-side base plate  22 , a handle-side base plate  23 , and a plurality of support shafts  24 , for example, as seen in  FIG. 3  and  FIG. 4 . 
   The printer-side base plate  22  extends along the direction of transport of the printing sheet L and thermal transfer ribbon R and also opposes the cassette attachment face  5  of the printer main body  2 . 
   The handle-side base plate  23  comprises a pair of handles  25  that oppose the printer-side base plate  22  by way of the support shafts  24  and that are used for the attachment operation of the cassette main body  21  in the printer main body  2 . 
   The support shafts  24  fix the printer-side base plate  22  and handle side base plate  23  at an interval of no less than the width of the printing sheet L and the thermal transfer ribbon R. 
   The cassette main body  21  facilitates attachment of a ribbon supply spindle  26  for supplying the thermal transfer ribbon R to the transport path  16  of the thermal transfer ribbon R and a winding supply spindle  27  for winding the thermal transfer ribbon R transported along the transport path  16  between the printer-side base plate  22  and handle-side base plate  23 . 
   The cassette main body  21  further comprises a cassette main body stay  28  having an upper surface of a comparatively broad surface area. 
   The cassette main body stay  28  is positioned between the printer-side base plate  22  and the handle-side base plate  23 . A main guide hole  29  is formed in the stay and the main guide shaft  7  that protrudes from the printer main body  2  side in the cassette main body  21  direction is insertable into the hole  29 . 
   Insertion of the main guide shaft  7  in the main guide hole  29  is facilitated by forming of the tip-end of the shaft in a tapered shape. 
   Moreover, an end of the main guide hole  29  of the cassette main body stay  28 , on the opposing side to the printer main body  2 , is open. This facilitates smooth insertion of the main guide shaft  7  in the main guide hole  29 . 
   A guide cut-away part  30  is formed in the printer-side base plate  22 , it is guidable along the upper surface and the arc-shaped end part  8 A of the printer main body stay  8  which extends from the printer main body  2  toward the printer-side base plate  22  and the circular arc-shaped end part of the part  30 . 
   A final positioning engagement hole  31  ( FIG. 6 ) is formed in the inner wall face side of the handle-side base plate  23 . It opposes the final positioning engagement pin  10  formed in the printer main body stay  8  of the printer main body  2  at the final positioning face  9 . 
   A printer main body opposing face  32  that opposes the printer main body  2  of the printer-side base plate  22  comprises a plurality (two in the example of the diagram) of assist engagement pins  33  ( FIGS. 4 and 6 ) provided toward the printer main body  2  side, and assist engagement holes  34  ( FIG. 5 ) engageable with the assist engagement pins  33  are formed in the cassette attachment face  5  of the printer main body  2 . 
   A magnet  35  ( FIG. 5 ) is provided in the cassette attachment face  5  of the printer main body  2  and an iron piece  36  ( FIG. 6 ) is provided on the printer main body opposing face  32  of the printer-side base plate  22  to facilitate the attachment of the cassette main body  21  (printer main body opposing face  32 ) to the printer main body  2  (cassette attachment face  5 ). 
     FIG. 7  is a main part perspective view of the cassette main body  21  as seen from the direction of the printer main body  2  in a state in which the thermal transfer ribbon R has not been loaded into the cassette main body  21 , and  FIG. 8  is a main part perspective view of the cassette main body  21  as seen from the printer main body  2  of the same. 
   A supply spindle guide groove  37  and winding spindle guide groove  38  ( FIG. 5 ,  FIG. 6 ) able to guide the ribbon supply spindle  26  and winding supply spindle  27  respectively in the set directions thereof are formed in the inner side wall face of the printer-side base plate  22  and handle-side base plate  23  respectively. Spindle receiving members (left-right pair of supply spindle receiver members  39  and winding spindle receiver members  40  in the respective axial directions thereof) able to fix the ribbon supply spindle  26  and the winding supply spindle  27  to their respective set positions are also provided. 
   More specifically, referring to  FIG. 5  as well as  FIG. 6 , the supply spindle receiver member  39  comprises a circular arc-shaped spindle part  39 A that is inserted and fixed in a supply spindle receiving hole  41  formed in the rearmost part of the supply spindle guide groove  37 , and a pair of guide flank parts  39 B that extend outward along the supply spindle guide groove  37  from the two end parts of the circular arc-shaped spindle part  39 A. 
   Similarly, the winding spindle receiver member  40  comprises a circular arc-shaped spindle part  40 A that is inserted and fixed in a winding spindle receiving hole  42  formed in the rearmost part of the winding spindle guide groove  38 , and a pair of guide flank parts  40 B that extend outward along the supply spindle guide groove  38  from the two end parts of the circular arc-shaped spindle part  40 A. 
   However, the supply spindle receiver member  39  and winding spindle receiver member  40  fixed in the inner wall face of the printer-side base plate  22  are narrower in width than the supply spindle receiver member  39  and winding spindle receiver member  40  fixed in the inner wall face of the handle-side base plate  23 . 
   Furthermore, the guide flank part  39 B of the supply spindle receiver member  39  and the guide flank part  40 B of the winding spindle receiver member  40  fixed in the inner wall face of the printer-side base plate  22  are smaller than the guide flank part  39 B of the supply spindle receiver member  39  and the guide flank part  40 B of the winding spindle receiver member  40  fixed in the inner wall face of the handle-side base plate  23 . 
   A plurality of axial direction protrusions  39 C and protrusions  40 C are formed protrudingly in the inner circumferential surface side of the circular arc-shaped spindle part  39 A and circular arc-shaped spindle part  40 A and, as a result of being engageable with a supply spindle circumferential groove  26 A and winding spindle circumferential groove  27 A formed in each of the end parts of the handle-side base plate  23  side of the ribbon supply spindle  26  and ribbon winding spindle  27 , the ribbon supply spindle  26  and winding supply spindle  27  are fixable to a section of the supply spindle receiver member  39  and winding spindle receiver member  40  and are prevented from easily falling out. 
   On the other hand, as shown in  FIG. 6  in particular, follower gears (supply spindle follower gear  26 B, winding spindle follower gear  27 B) are formed in the end parts of the printer main body  2  (cassette attachment face  5 ) side of the ribbon supply spindle  26  and the winding supply spindle  27 . 
   As shown in  FIG. 5  in particular, the supply spindle follower gear  26 B and winding spindle follower gear  27 B, are engageable by way of the supply spindle receiving hole  41  and the winding spindle receiving hole  42  respectively with follower gears (supply spindle driver gear  43 , supply spindle driver gear  44 ) that face the cassette attachment face  5  of the printer main body  2 . 
   Furthermore, similarly to the supply spindle follower gear  26 B and winding spindle follower gear  27 B, detection gears (supply spindle detection gear  26 C, winding spindle detection gear  27 C) of larger diameter than the supply spindle follower gear  26 B and winding spindle follower gear  27 B are formed in the end parts of the ribbon supply spindle  26  and the winding supply spindle  27  to be engageable by way of open windows (supply spindle open window  47 , winding spindle open window  48 ) with sensor-side gears (supply spindle sensor-side gear  45 , winding spindle sensor-side gear  46 ). 
     FIG. 9  is a main part expanded perspective view of the supply spindle driver gear  43  and winding spindle driver gear  44 , as well as the supply spindle sensor-side gear  45  and winding spindle sensor-side gear  46  components facing the cassette attachment face  5  of printer main body  2 , and  FIG. 10  is a main part expanded perspective view of the supply spindle follower gear  26 B and winding spindle follower gear  27 B components that face the printer main body opposing face  32  of the cassette main body  21  (printer-side base plate  22 ). 
   As shown in  FIG. 9  in particular, the supply spindle driver gear  43  comprises an engagement center pin  43 A that protrudes from the center part thereof, and an engagement gear  43 B that is formed slightly lower in the circumference of the engagement center pin  43 A. 
   The winding spindle driver gear  44  comprises an engagement center pin  44 A that protrudes from the center part thereof, and an engagement gear  44 B that is formed slightly lower in the circumference of the engagement center pin  44 A. 
   As shown in  FIG. 10  in particular, an engagement center hole  26 D and engagement center hole  27 D are formed in the center part of the supply spindle follower gear  26 B and winding spindle follower gear  27 B in the ribbon supply spindle  26  and winding supply spindle  27  to facilitate engagement with the engagement center pin  43 A and the engagement center pin  44 A respectively. Moreover, by the adoption of a tapered shape end part of each of the engagement center pin  43 A and engagement center pin  44 A, the engagement thereof with the engagement center hole  26 D and engagement center hole  27 D respectively is simple and reliable. 
   Furthermore, by the adoption of a tapered shape gear end part of each of the follower gears (supply spindle follower gear  26 B, winding spindle follower gear  27 B) and the engagement gear  43 B and engagement gear  44 B of the driver gears (supply spindle driver gear  43 , winding spindle driver gear  44 ), the engagement operations therebetween can be implemented easily and reliably irrespective of the turning position (position in the circumferential direction) of the ribbon supply spindle  26  and the winding supply spindle  27 . 
   In addition, by the adoption of a tapered shape gear end part of each of also the supply spindle detection gear  26 C and winding spindle detection gear  27 C and the supply spindle sensor-side gear  45  and winding spindle sensor-side gear  46  of the ribbon supply spindle  26  and winding supply spindle  27  respectively, the engagement operations therebetween can be implemented easily and reliably. 
   Detection discs (supply spindle detection disc  49 , winding spindle detection disc  50 ) comprising slits in the circumference are concentrically mounted with the supply spindle sensor-side gear  45  and the winding spindle sensor-side gear  46  respectively, and detection of the rotation state of the ribbon supply spindle  26  and winding supply spindle  27  being facilitated by rotation sensors (supply spindle rotation sensor  51 , winding spindle rotation sensor  52 ). 
   The ribbon supply spindle  26  and winding supply spindle  27  are divided between the printer-side base plate  22  and handle-side base plate  23  (details omitted), and these divided components are independently rotatable structures. 
   Accordingly, whenever the supply spindle circumferential groove  26 A is engaged with the circular arc-shaped spindle part  39 A and the winding spindle circumferential groove  27 A is engaged with the circular arc-shaped spindle part  40 A (see  FIG. 6 ) in the handle-side base plate  23  side and, furthermore, with reference to  FIG. 5  and  FIG. 6 , whenever the supply spindle follower gear  26 B is engaged with the supply spindle driver gear  43  and the winding spindle follower gear  27 B is engaged with the winding spindle driver gear  44  in the printer-side base plate  22  side and, in addition, whenever the supply spindle sensor-side gear  45  is engaged with the supply spindle detection gear  26 C and the winding spindle detection gear  27 C is engaged with the winding spindle sensor-side gear  46 , each of the ribbon supply spindle  26  and winding supply spindle  27  are rotatable between the printer-side base plate  22  and the handle-side base plate  23  to facilitate the supply and winding of the thermal transfer ribbon R. 
   Moreover, as shown in  FIG. 2 ,  FIG. 5  and  FIG. 6  and other diagrams, transport assist rollers (upstream-side assist roller  53 , and downstream-side assist roller  54 ) to assist in transporting of the thermal transfer ribbon R are provided between the printer-side base plate  22  and handle-side base plate  23  in the upstream side and downstream side of the platen roller  12  along the transport path  16  of the thermal transfer ribbon R. 
   The upstream-side assist roller  53  and downstream-side assist roller  54  are rotatably supported between the printer-side base plate  22  and handle-side base plate  23 , and follower gears (upstream side follower gear  53 A, downstream-side follower gear  54 A) are each formed in the printer main body  2  side of the upstream-side assist roller  53 . 
   As shown in  FIG. 5  in particular, the upstream-side assist roller  53  and downstream-side assist roller  54  are rotatably-drivable by means of the follower gears (upstream-side driver gear  55 , downstream-side driver gear  56 ) that face the cassette attachment face  5  of the printer main body  2 . 
   The upstream-side follower gear  53 A of the upstream-side assist roller  53  is engageable with the upstream-side driver gear  55  by way of an opposing face gear  57  provided in the printer main body opposing face  32  of the printer-side base plate  22  ( FIG. 6 ) and a timing belt  58  ( FIG. 5 ) provided in the side opposing the handle-side base plate  23  on the opposing side to the printer main body opposing face  32  of the printer-side base plate  22 . 
   The downstream-side follower gear  54 A of the downstream-side assist roller  54  is directly engageable with the downstream-side driver gear  56 . 
   As shown in  FIG. 2 ,  FIG. 5  and  FIG. 9  in particular, a guide pin  59  of which the tip-end part is formed in a tapered shape is protrudingly provided from the cassette attachment face  5  of the printer main body  2  in the region of the magnet  35 , and a through-hole  60  ( FIG. 6 ,  FIG. 10 ) with which the guide pin  59  is engageable is formed in the printer-side base plate  22  whereupon, when the cassette main body  21  is moved toward and abuts the cassette attachment face  5 , a reliable adsorption is established between the magnet  35  and iron piece  36  and a reliable engagement of the upstream-side assist roller  53  and downstream-side assist roller  54  with the upstream-side driver gear  55  and downstream-side driver gear  56  is established. 
   In addition, a brush member  61  which performs an anti-static action on the thermal transfer ribbon R is provided in the downstream side of the platen roller  12  to extend across the transport path  16  of the thermal transfer ribbon R. 
     FIG. 11  is a main part expanded perspective view of the head opening/shutting lever  13  component, the head opening/shutting lever  13  being attachable with a lever fixing pin  62  protrudingly fixed in the base frame  6  so that the thermal head  11  is able to be pressed at a predetermined pressure on the platen roller  12 . 
   The cassette attachment lever  63  is concentrically provided about the lever shaft  17  of the head opening/shutting lever  13 , the cassette attachment lever  63  and head opening/shutting lever  13  being connected to be integrally operable. 
   Accordingly, a head lock (approach/separate operation) between the thermal head  11  and platen roller  12  and a cassette lock (mounting operation) of the cassette main body  21  in the printer main body  2  can be jointly implemented by operation of this single cassette attachment lever  63 . This facilitates improvement to the assembly workability and a reduction in the number of assembly steps. 
   Furthermore, the base plate interval  64  slightly larger than the thickness of the printer-side base plate  22  of the cassette main body  21  is provided between the head opening/shutting lever  13  and the cassette attachment lever  63 . 
   Accordingly, as a result of the base plate interval  64  section being positioned in the printer-side base plate  22  subsequent to the cassette attachment lever  63  being operated in the lock direction (anti-clockwise direction in  FIG. 11 ) after the cassette main body  21  has been pushed in the printer main body  2  direction until the printer main body opposing face  32  of the cassette main body  21  has abutted the cassette attachment face  5  of the printer main body  2 , that is to say, as a result of the head opening/shutting lever  13  and cassette attachment lever  63  being positioned on the upper and lower faces of the printer-side base plate  22 , the ribbon cassette apparatus  3  (cassette main body  21 ) as a whole is fixable to the printer main body  2  side and fallout of the cassette main body  21  from the printer main body  2  side is prevented. 
   Moreover, a guide cut-away part  30  ( FIG. 5 ) is formed in the printer-side base plate  22  and, when the ribbon cassette apparatus  3  as a whole is moved toward the handle-side base plate  23  in the printer main body  2  direction, a lever window part  65  through which the head opening/shutting lever  13  and the cassette attachment lever  63  are able to pass ( FIG. 5 ) in the opened state of the thermal head  11  with respect to the platen roller  12  is formed whereupon, in the opened state of the thermal head  11  described above, a mounting operation of the cassette main body  21  in which it is moved until abutting the printer main body  2  without colliding with the head opening/shutting lever  13  and the cassette attachment lever  63  is possible. 
     FIG. 12  is a perspective view showing a state in which the cassette attachment lever  63  is operated after the cassette main body  21  (ribbon cassette apparatus  3 ) has been inserted in the printer main body  2 , the head opening/shutting lever  13  integral with the cassette attachment lever  63  being engaged with the lever fixing pin  62  to complete the mounted state of the ribbon cassette apparatus  3  in the printer main body  2  as a result of the turning operation of the cassette attachment lever  63  from the virtual line to the state shown by the solid line in the diagram. 
   As shown in  FIG. 1  in particular, the cover  4  mounted on the cassette attachment face  5  of the printer main body  2  fulfils a dust-prevention and waterproofing function, and an insert opening hole  66  is formed in the cassette main body  21  to facilitate guiding of the cassette main body  21  to the printer main body  2  side. 
   When the cassette main body  21  is directed toward the printer main body  2  side and is subsequently moved toward the printer main body  2 , the guide direction and position of the cassette main body  21  is clearly indicatable to an operator performing the mounting through the cover  4  itself and, in reality, a guiding of the left and right edge parts and upper edge part of the printer-side base plate  22  and handle-side base plate  23  of the cassette main body  21  is performed. 
   Moreover, a transparent window  67  that facilitates confirmation from the exterior with the naked eye of the thermal transfer ribbon R in the interior of the cover  4  is formed in the approximate center part of the handle-side base plate  23 . Naturally, an equivalent transparent window can also be formed in the upper part of the cover  4 . 
   In a thermal transfer printer  1 , printer main body  2  and ribbon cassette apparatus  3  of this configuration, the mounting of the ribbon cassette apparatus  3  in the printer main body  2  is based on the handles  25  being held and the cassette main body  21  being operated in the printer main body  2  direction. 
   First, the main guide hole  29  of the cassette main body stay  28  is engaged with the cassette main body  21  of the main guide shaft  7  of the printer main body  2  and, furthermore, the guide cut-away part  30  of the printer-side base plate  22  is moved along the upper surface of the printer main body stay  8  and the arc-shaped end part  8 A thereof as the cassette main body  21  is moved toward the cassette attachment face  5  of the printer main body  2 . 
   Next, the cassette main body  21  is able to be attached to the printer main body  2  as a result of the engagement of the assist engagement pins  33  of the printer-side base plate  22  with the assist engagement holes  34  in the cassette attachment face  5  of the printer main body  2  and, in addition, the engagement of the guide pin  59  in the cassette attachment face  5  with the through-hole  60  in the printer-side base plate  22  and, furthermore, the engagement of the final positioning engagement pin  10  of the printer main body stay  8  with the final positioning engagement hole  31  of the handle-side base plate  23 , the cassette main body  21  being opposed to the printer main body  2  with a predetermined position accuracy with adsorption between the magnet  35  and the iron piece  36 . 
   In this attached state, the follower gears (supply spindle follower gear  26 B, winding spindle follower gear  27 B) of the ribbon supply spindle  26  and winding supply spindle  27  are engaged with the drive gears (supply spindle driver gear  43 , winding spindle driver gear  44 ) of the printer main body  2 , and the detection gears thereof (supply spindle detection gear  26 C, winding spindle detection gear  27 C) are engaged with the sensor gears (supply spindle sensor-side gear  45 , winding spindle sensor-side gear  46  ) of the printer main body  2 . 
   Simultaneously with this engagement, follower gears (upstream-side follower gear  53 A, downstream-side follower gear  54 A) of the upstream-side assist roller  53  and downstream-side assist roller  54  are engaged with the driver gears (upstream-side driver gear  55 , downstream-side driver gear  56 ) of the printer main body  2 . 
   Finally, as shown in  FIG. 12 , in an operation using the cassette attachment lever  63  to effect completion of the mounting operation, a head lock between the thermal head  11  and platen roller  12  (approach/separate operation) and a cassette lock of the cassette main body  21  on the printer main body  2  (mounting operation) is performed. 
   Removal of the cassette main body  21  from the printer main body  2  involves, upon release of the cassette lock and head lock by a turning operation of the cassette attachment lever  63  in the clockwise direction of  FIG. 12 , the handles  25  being held and the cassette main body  21  as a whole being pulled out from the printer main body  2  whereupon, conversely to that described above, the adsorption and engagements between the cassette main body  21  and printer main body  2  are released to allow the cassette main body  21  to be removed. 
   By the attachment of the main guide hole  29  of the cassette main body stay  28  and the main guide shaft  7  of the printer main body  2  and the attachment of the final positioning engagement hole  31  of the handle-side base plate  23  with the final positioning engagement pin  10  of the printer main body stay  8  in this way in particular, the cassette main body  21  can be attached to the printer main body  2  with a predetermined relative positional accuracy. 
   Furthermore, the ribbon supply spindle  26  and winding supply spindle  27  can be set in advance in the cassette main body  21 , and the operation for the replacement of the thermal transfer ribbon R can be implemented easily. 
   In addition, because the mounting operation itself of the cassette main body  21  is a simple operation requiring simply a pushing thereof while the handles  25  are being held, the cassette main body  21  can be easily mounted without effect on the position and positional arrangement of the printer main body  2 . 
   Naturally, because it involves holding of a left-right pair of handles  25 , the mounting operation in which the cassette main body  21  is moved toward the printer main body  2  side can be stably performed. 
   Various alterations and supplementary configurations can be made to the present invention in accordance with need. 
   For example,  FIG. 13  is a front view of a ribbon cassette apparatus  70  based on a second embodiment of the present invention in which, in addition to the previously described configuration, that is to say, a configuration in which the lever fixing pin  62  is provided in the base frame  6  of a printer main body  2  and the head opening/shutting lever  13  is attachably provided in the lever fixing pin  62  so that the thermal head  11  is able to be maintained in a pressed state at a predetermined pressure in the platen roller  12 , in the ribbon cassette apparatus  70  the base frame  6  and cassette main body  21  may be firmly fixed to each other. 
   More specifically, the handle-side base plate  23  is able to be fixed to the base frame  6  by the provision of an assist opening/shutting lever  71  in the handle-side base plate  23  in the upstream-side of the transport path  16  from the platen roller  12  part that is tumably operable around an assist lever shaft  72 , and the provision of an assist lever pin  73  in the base frame  6  and engagement of the assist lever pin  73  and the assist opening/shutting lever  71 . 
   According to this configuration, as a result of the integration of base frame  6  with the cassette main body  21  afforded by the engagement of the head opening/shutting lever  13  and the cassette attachment lever  63  with the lever fixing pin  62  in the region of the platen roller  12  and the integration with the cassette main body  21  afforded by the engagement of the assist opening/shutting lever  71  with the assist lever pin  73  of the upstream-side of the platen roller  12 , the handle-side base plate  23  (ribbon cassette apparatus  70 ) and base frame  6  are reliably supported in two places. 
   Accordingly, the vibration of the base frame  6  component accompanying printing on the thermal transfer ribbon R and the transport thereof and, furthermore, the possibility of the vibration increasing in the thermal transfer printer  1  as a whole accompanying an increase in the size of the thermal transfer ribbon R and the cassette main body  21  can be suppressed, and undesirable effects to the printing on the thermal transfer ribbon R and the transport thereof in the thermal transfer printer  1  can be avoided. 
     FIG. 14  is a main part expanded view of the cassette main body stay  28  as seen from the printer main body  2  side in a ribbon cassette apparatus  80  based on a third embodiment of the present invention in which, in the ribbon cassette apparatus  80 , a rubber cushion member or other elastic member  81  is mounted to abut the opening edge part in particular of the main guide hole  29  of the cassette main body stay  28  in the printer-side base plate  22  of the cassette main body  21  thereof facing the cassette attachment face  5  of the printer main body  2 . 
     FIG. 15  is a main part expanded perspective view of the cassette main body stay  28  component as seen in the printer main body  2  direction, an end part of the main guide hole  29  of the cassette main body stay  28  of the opposing side to the printer main body  2  being closed. 
   In the ribbon cassette apparatus  80  of this configuration the impact noise generated when the cassette main body  21  is attached to the printer main body  2  can be suppressed, the wear of the cassette main body  21  (printer-side base plate  22 ) can be suppressed, and the durability thereof can be improved by the elastic member  81 . Furthermore, because the main guide hole  29  is opened only in the printer-side base plate  22  the residual air within the main guide hole  29  performs an air-damper action accompanying the engagement of the main guide hole  29  and main guide shaft  7  and, accordingly, even if the operation for mounting the ribbon cassette apparatus  80  in the printer main body  2  is performed quickly, the speed of insertion thereof is slowed as it is inserted and, in the end, a gentle insertion action that allows the mounting operation to be completed with reduced impact is facilitated. 
   Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein, but only by the appended claims.