Abstract:
Provides an automatic changer with excellent space efficiency, by reducing the size of a hand mechanism section that is mounted with a CCD. The automatic changer selects and holds one desired cartridge from among one of accommodation cells provided in a magazine, conveys this selected cartridge to a recording/reproducing apparatus, and reads a bar code label adhered to the side surface of the cartridge thereby to identify the cartridge. The automatic changer has the CCD that reads a bar code disposed in the inner part of a casing that movably accommodates a hand mechanism section for holding the cartridge. The automatic changer also has a condenser lens for focusing the image of the bar code on the CCD disposed at one part of the hand mechanism section. With this arrangement, the automatic changer moves the hand mechanism section to the front of the cartridge accommodated in the accommodation cell, and focuses the image of the bar code on the CCD. Then, the CCD identifies the contents of the cartridge.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to an automatic changer and, more particularly, to an automatic changer that selects one cartridge-type recording medium from among a large number of such recording media accommodated in a recording/reproducing apparatus, and moves this selected recording medium to a desired position.  
           [0003]    2. Description of the Related Art  
           [0004]    Conventionally, there has been practically used an automatic changer for cartridge-type recording media which is structured to accommodate a plurality of double-reel type audio or video cassette tapes or single-reel type data recording cartridge tapes on shelves within one accommodation box. The automatic changer selects one desired tape from among these tapes, and conveys this tape to a reproducing or recording apparatus.  
           [0005]    This automatic changer is used being connected to a computer system such as a server, personal computer, and so on. In this automatic changer, a plurality of cartridges are accommodated on shelves, and a hand mechanism section is provided on an accessor that is movably structured to hold and convey a cartridge. A bar code label is adhered to a surface of each cartridge at the hand mechanism section side.  
           [0006]    On the other hand, a bar code reader is provided on a base section of the hand mechanism section adjacent to the hand mechanism section. This bar-code reader reads the bar code label adhered to each cartridge, and identifies this cartridge. The conventional library device uses a laser bar-code reader. This bar-code reader irradiates laser beams onto the cartridge over a predetermined range of this cartridge, and reads the bar code.  
           [0007]    Japanese Patent Application Laid-open Publication No. 5-144147 discloses an automatic changer that is an improved conveyor of an automatic cassette changer for a television broadcasting station that is used to reproduce or edit the recording of a series of videos over many hours while changing a plurality of video cassettes. According to this automatic changer, a bar-code reader provided on the hand mechanism section of this automatic changer can directly and continuously read bar codes provided on the side surfaces of cassettes, in order to specify a plurality of cassettes accommodated on a plurality of shelves.  
           [0008]    Further, according to the automatic changer disclosed in Japanese Patent Application Laid-open Publication No. 5-144147, a hand block selectively holds one of the plurality of cassettes accommodated on the plurality of accommodation shelves, and conveys this selected cassette to a recording/reproducing apparatus. A label printed with a bar code is adhered to the hand-block side end surface of each cassette accommodated on each accommodation shelf.  
           [0009]    The hand block is fitted to the conveyor via an arm, to move freely between the accommodation shelf and the recording/reproducing apparatus to convey one cassette. For this purpose, four cassette-holding pins are provided on the hand block to hold one cassette. On the side surface of the hand block, a bar-code reader is adhered to scan and read bar codes of the plurality of cassettes.  
           [0010]    Further, according to the automatic changer disclosed in Japanese Patent Application Laid-open Publication No. 5-144147, the hand block moves the bar-code reader along the bar codes of the plurality of cassettes that are accommodated on the plurality of accommodation shelves. The bar-code reader sequentially and continuously reads these bar codes, and identifies each cassette.  
           [0011]    However, in recent years, an apparatus that utilizes a CCD (charged-coupled device) has come to be practically used as an image pick-up member, instead of using laser beams to read bar codes. According to this apparatus that utilizes the CCD, the CCD reads an image of a bar code, analyzes this image, and reads the contents of the bar code. In order for the CCD to read the bar code, it is necessary to provide a condenser lens that focuses the image of the bar code on the CCD.  
           [0012]    However, as the bar-code reader of the library device is a large laser type, and is mounted adjacent to the hand mechanism section, the movable range of the hand mechanism section becomes small. Therefore, the space in which the cartridges are accommodated has become narrow. Further, there is a range of distance over which the bar-code reader can read bar codes. Therefore, there has been a risk that the bar-code reader cannot read bar codes when the distance between the bar-code reader and the bar code labels changes.  
           [0013]    Further, according to the automatic changer disclosed in Japanese Patent Application Laid-open Publication No. 5-144147, the bar-code reader is mounted on the side surface of the hand mechanism section. Therefore, there has been a problem that the hand mechanism section is large, and a wasteful space is generated in the apparatus. When a reflection-type sensor or a laser-type sensor is mounted on the bar-code reader, there is margin in the reading distance from the bar-code reader to the bar code labels. However, these types of sensors are very expensive, and the mounting of these devices leads to a high cost of the bar-code reader.  
           [0014]    On the other hand, when a CCD is used to read the bar codes, it is possible to minimize the cost of the bar-code reader, as the CCD is at a very low cost (ten percent of the cost of the laser type). However, this has had a problem that there is no margin in the reading distance. In order to solve this problem, a condenser lens is fitted to a holding mechanism of the hand mechanism section that moves forward and backward. By controlling the lens position (that is, by automatically focusing the image of the bar code), the distance margin for the reading is increased. However, as the CCD and the condenser lens are also mounted in this case, a large space is necessary for their accommodation. Therefore, the hand mechanism section is large, and this limits the moving area of the hand mechanism section. Consequently, there has been a problem that only a small number of cartridges can be accommodated in the automatic changer.  
         SUMMARY OF THE INVENTION  
         [0015]    It is, therefore, an object of the present invention to provide an automatic changer in which it is possible to accommodate a large number of cartridges, with excellent space efficiency, without increasing the size of a hand mechanism section, even when a CCD that requires the mounting of a condenser lens is mounted on the hand mechanism section in order to read identifiers printed on labels adhered to cartridges that accommodate recording media.  
           [0016]    In order to achieve the above object, according to one aspect of the present invention, there is provided an automatic changer comprising a cartridge accommodating section that accommodates a plurality of cartridges such that these cartridges can be selected, and an accessor that selects one cartridge from the accommodating section, and conveys the selected cartridge to a predetermined position within a casing, the automatic changer being structured to read an identifier of a label adhered to at least one surface of a cartridge, and identifies each cartridge, wherein a hand mechanism that holds a cartridge and pulls the cartridge into the internal space or releases the cartridge from the internal space, is provided within an internal space that accommodates the cartridges; an identifier-image pick-up member is disposed in the inner part of the internal space; a condenser lens is disposed on an optical axis of the image pick-up member in a move direction of the hand mechanism; and the hand mechanism in a status of not holding the cartridge is moved within the internal space thereby to focus the identifier on the image pick-up member.  
           [0017]    Further, according to another aspect of the invention, the image pick-up member may be a CCD. Further, a cartridge may be a magnetic-tape cartridge, a cartridge that accommodates an optical magnetic disk, or a cartridge that accommodates a non-volatile IC memory.  
           [0018]    Further, according to still another aspect of the invention, in general, it is possible to use a bar code for the identifier. It is also possible to use a mark other than a bar code for the identifier.  
           [0019]    Further, according to still another aspect of the invention, there is provided an automatic changer in which the accessor is structured to be able to move along a guide rail provided on a floor surface of the casing in a width direction; cartridge accommodating sections are provided at both sides of the accessor along a moving direction of the accessor; and a rotation mechanism is provided that can convey a cartridge to any one of the cartridge accommodating sections based on a rotation of the accessor in a horizontal direction.  
           [0020]    Further, according to still another aspect of the invention, there is provided the automatic changer of the above aspect wherein a driver, as a recording/reproducing apparatus to which the accessor conveys a cartridge, is provided at one side of the accessor in its moving direction. Further, according to still another aspect of the invention, there is provided the automatic changer of the above aspect wherein the cartridge accommodating section at one side at which the driver is provided is fixed, and the other cartridge accommodating section at the other side is formed as a magazine that can be exchanged. Further, according to still another aspect of the invention, there is provided the automatic changer of the above aspect wherein the magazine that can be exchanged is detachably fitted to an open/close window of the automatic changer. Further, according to still another aspect of the invention, there is provided the automatic changer of the above aspect wherein a ball screw applied in a width direction of the casing is engaged with the other end of the guide rail of the accessor, and the accessor moves based on a rotation of the ball screw.  
           [0021]    According to the automatic changer of the present invention, the image pick-up member that reads an identifier attached to a cartridge and recognizes this cartridge and the condenser lens are provided within the casing and the hand mechanism of the accessor respectively. Therefore, the image pick-up member and the condenser lens do not stretch out from the accessor, and it becomes possible to make the accessor compact. As a result, it is possible to reduce the sizes of the automatic changer and increase the number of cartridges accommodated within the automatic changer, without changing the sizes of the automatic changer. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    The present invention will be more clearly understood from the description as set forth below with reference to the accompanying drawings, wherein:  
         [0023]    [0023]FIG. 1 is a perspective view of a part of a structure of an automatic changer in a conventional library device;  
         [0024]    [0024]FIG. 2A is a perspective view showing a structure of an automatic changer described in a conventional publication;  
         [0025]    [0025]FIG. 2B is a perspective view of a hand block shown in FIG. 2A as viewed from a cassette side;  
         [0026]    [0026]FIG. 3A is a perspective view of an automatic magnetic-tape changer according to one embodiment of the present invention as viewed from the front side;  
         [0027]    [0027]FIG. 3B is a perspective view of the automatic changer shown in FIG. 3A as viewed from the back side;  
         [0028]    [0028]FIG. 4A is a perspective view of a magnetic-tape cartridge that is incorporated in the automatic magnetic-tape changer shown in FIGS. 3A and 3B;  
         [0029]    [0029]FIG. 4B is a perspective view of a magnetic-tape cartridge that shows a state where a magnetic tape is drawn out from the magnetic-tape cartridge shown in FIG. 4A;  
         [0030]    [0030]FIG. 4C is a diagram showing one example of a bar code label inscribed with a bar code that is adhered to side surface of the magnetic-tape cartridge shown in FIGS. 4A and 4B;  
         [0031]    [0031]FIG. 5A is a top plan view for explaining an internal structure of the automatic magnetic-tape changer shown in FIGS. 3A and 3B, with a ceiling plate removed from the automatic changer;  
         [0032]    [0032]FIG. 5B is a side view of the automatic changer shown in FIG. 5A;  
         [0033]    [0033]FIG. 6A is a perspective view of one embodiment of an accessor that constitutes the automatic changer of the present invention;  
         [0034]    [0034]FIG. 6B is a partially-cutaway perspective view of an internal structure of the automatic changer shown in FIG. 6A, with a side wall removed from the automatic changer;  
         [0035]    [0035]FIG. 6C is a partially-cutaway perspective view of the automatic changer showing a state where a hand mechanism section shown in FIG. 6B has moved to a position of reading a bar code adhered to the magnetic tape cartridge;  
         [0036]    [0036]FIG. 7 is a side view of the automatic magnetic-tape changer of the present invention showing a state where an accessor is reading a bar code at a position of reading the bar code adhered to the magnetic tape cartridge;  
         [0037]    [0037]FIG. 8A is a perspective view of the automatic changer shown in FIG. 6 showing a state where the hand mechanism section holds a magnetic-tape cartridge;  
         [0038]    [0038]FIG. 8B is a perspective view of the automatic changer showing a state where the magnetic-tape cartridge has been pulled into the automatic changer from the status shown in FIG. 8A;  
         [0039]    [0039]FIG. 9A is a perspective view of another embodiment of a magnetic-tape cartridge that is used in the automatic changing of the present invention;  
         [0040]    [0040]FIG. 9B is a diagram showing one example of a bar code that is adhered to the side surface of the magnetic-tape cartridge shown in FIG. 9A;  
         [0041]    [0041]FIG. 9C is a perspective view of still another embodiment of a magnetic-tape cartridge that is used in the automatic changing of the present invention; and  
         [0042]    [0042]FIG. 9D is a diagram showing one example of a bar code that is adhered to the side surface of the magnetic-tape cartridge shown in FIG. 9C. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0043]    Before describing the preferred embodiments, an explanation will be given of a conventional automatic changer for a cartridge-type recording medium shown in FIGS.  1  to  2 B.  
         [0044]    [0044]FIG. 1 shows a part of an automatic magnetic-tape cartridge changer in a magnetic-tape library device as a large-capacity storage that is connected to a large computer system. This automatic changer has a hand mechanism section  91  provided on an accessor that is movably structured to hold and convey a cartridge  90  as a recording medium. A plurality of cartridges  90  are accommodated on shelves provided within the library device, and a bar code label is adhered to a surface of each cartridge at the hand mechanism section side. On the other hand, a bar code reader  93  is provided on a base section  92  of the hand mechanism section  91 , adjacent to the hand mechanism section  91 . This bar-code reader  93  reads the bar code label adhered to the cartridge  90 , and identifies this cartridge  90 . The conventional library device uses a laser-type bar-code reader for the bar-code reader  93 . This bar-code reader  93  irradiates laser beams onto the cartridge  90  over a range shown by broken lines, and reads the bar code.  
         [0045]    The automatic changer disclosed in Japanese Patent Application Laid-open Publication No. 5-144147 is an improved conveyor of an automatic cassette changer for a television broadcasting station that is used to reproduce or edit the recording of series of videos over many hours while changing a plurality of video cassettes. According to this automatic changer, a bar-code reader provided on the hand mechanism section of this automatic changer can directly and continuously read bar codes provided on the side surfaces of cassettes, in order to specify a plurality of cassettes accommodated on a plurality of shelves.  
         [0046]    [0046]FIGS. 2A and 2B show structures of the automatic changer disclosed in Japanese Patent Application Laid-open Publication No. 5-144147. According to the automatic changer disclosed in this publication, a hand block  191  selectively holds one of the plurality of cassettes  190  accommodated on a plurality of accommodation shelves  196 , and conveys this selected cassette to a recording/reproducing apparatus not shown. A label printed with a bar code  192  is adhered to an end surface  193 , at the side of the hand block  191 , of each cassette  190  accommodated on each accommodation shelf  196 .  
         [0047]    The hand block  191  is fitted to the conveyor, not shown, via an arm  180 , to move freely between the accommodation shelf  196  and the recording/reproducing apparatus, not shown, to convey one cassette  190 . For this purpose, four cassette-holding pins  182  and  183  are provided on the hand block  191  to hold one cassette. On the side surface of the hand block  191 , a bar-code reader  195  is adhered to scan and read bar codes  192  of the plurality of cassettes  190  in a direction as shown by arrows f′ and f.  
         [0048]    Further, according to the automatic changer disclosed in Japanese Patent Application Laid-open Publication No. 5-144147, the hand block  191  moves the bar-code reader  195  in the direction of the arrows f′ and f along the bar codes  192  of the plurality of cassettes  190  that are accommodated on the plurality of accommodation shelves  196 . The bar-code reader  195  sequentially reads these bar codes  192  continuously, and identifies each cassette  190 .  
         [0049]    However, in recent years, an apparatus that utilizes a CCD (charged-coupled device) has come to be practically used as an image pick-up member, instead of using laser beams to read bar codes. According to this apparatus that utilizes the CCD, the CCD reads an image of a bar code, analyzes this image, and reads the contents of the bar code. In order to enable the CCD to read a bar code, it is necessary to provide a condenser lens that focuses the image of the bar code on the CCD.  
         [0050]    Embodiments of the present invention will be explained in detail below with reference to the attached drawings.  
         [0051]    [0051]FIG. 3A is a perspective view of an automatic magnetic-tape changer  1  according to one embodiment of the present invention as viewed from the front side, and FIG. 3B is a perspective view of this automatic changer  1  as viewed from the back side. An open/close window  2  for exchanging recording media that are accommodated inside this automatic magnetic-tape changer  1  is provided at the front-surface side of this automatic changer. An operation panel  3  is provided on this open/close window  2 . At the back-surface side of this automatic magnetic-tape changer  1 , there are provided a power source switch  4 , a power source terminal  5  to which a power source cord is connected, and a data input/output connector  6 . A reference number  7  denotes an open/close knob that is provided on the open/close window  2 . When this knob  7  is pulled, the open/close window is opened.  
         [0052]    A magnetic tape cartridge (hereinafter to be simply referred to as a cartridge)  10  as shown in FIG. 4A, for example, is provided as a recording medium, in a large number, in the automatic magnetic-tape changer  1  of this embodiment. An identification label adhesion area  11  and a magnetic-tape drawing opening  12  for a magnetic tape wound around an incorporated reel are provided on the side surface of the cartridge  10 . When the cartridge  10  is inserted into a recording/reproducing apparatus (drive) to be described later, a magnetic tape  13  is drawn out and guided, by a leader pin  14 , from the drawing opening  12 , as shown in FIG. 4B. A bar code label  15  printed with a bar code as an identifier is adhered to the identification label adhesion area  11  of the cartridge, as shown in FIG. 4C. It is possible to recognize a volume number and the contents of the volume of each cartridge  10 , by reading the bar code printed on this bar code label  15 .  
         [0053]    For the label adhered to the identification label adhesion area  11 , it is also possible to use a label printed with a two-dimensional bar code, or a label printed with a mark or a symbol, in addition to the bar code label  15  printed with the bar code.  
         [0054]    [0054]FIG. 5A shows an internal structure of the automatic magnetic-tape changer  1  explained with reference to FIGS. 3A and 3B, and FIG. 5B shows a side view of this automatic changer shown in FIG. 5A. It is possible to open the open/close window  2  forward with the know  7  shown in FIG. 3A, as shown in FIG. 5B. In this example, a magazine  20  having seven cells  21  for accommodating cartridges  10  is fitted to the inside of the open/close window  2 . A knob  22  is provided on the upper portion of the magazine  20 , and this knob  22  is used to take out the magazine  20  from the open/close window  2 . The magazine  20  is fitted to the inside of the open/close window  2  in a state where the magazine  20  usually accommodates the cartridges  10  as recording media in the cells  21 .  
         [0055]    A fixed holder  26  having four cells that accommodate cartridges  10  is provided inside the automatic magnetic-tape changer  1 . Each cell of the fixed holder  26  is open to the open/close window  2  side. A driver  27  as the recording/reproducing apparatus of the cartridges  10  is provided adjacent to the fixed holder  26 . Further, a power source  28  is provided at a furthest position from the open/close window  2  inside the automatic magnetic-tape changer  1 . A main board  29  installed with a control circuit of the automatic magnetic-tape changer  1  is provided above the power source  28  and the driver  27 .  
         [0056]    A space is provided between the magazine  20  and the fixed holder  26  in a state where the open/close window  2  is closed. An accessor  30  that can move in a width direction of the automatic magnetic-tape changer  1  is provided in this space. This accessor  30  holds a cartridge  10  that is accommodated in the cell  21  of the magazine or in the fixed holder  26 , and conveys this cartridge to the driver  27 . The accessor  30  also returns a cartridge  10  that is in the driver  27  to the magazine  20  or the fixed holder  26 . The lower portion of this accessor  30  is positioned on a guide rail  23  provided on the floor surface of the automatic magnetic-tape changer  1  in its width direction. The upper portion of the accessor  30  is engaged with a ball screw  24  applied in a width direction of the automatic magnetic-tape changer  1 . The accessor  30  moves in the width direction of the automatic magnetic-tape changer  1  based on the rotation of the ball screw  24 . A rotation mechanism of the ball screw  24  consists of a motor  16  that is provided in the upper space of the automatic magnetic-tape changer  1 , a pulley  17  fitted to the rotation axis of the motor  16 , a pulley  19  fitted to one end of the ball screw  24 , and a timing belt  18  that is applied between the pulley  17  and the pulley  19 .  
         [0057]    A rotation mechanism  25  that makes the accessor  30  rotate by 180 degrees is provided at the center of the guide rail  23 . The accessor  30  can accommodate a cartridge  10  from only one side surface of the accessor  30  into the main body. Therefore, this rotation mechanism  25  is necessary to enable the accessor  30  to make access to both the magazine  20  and the fixed holder  26 .  
         [0058]    [0058]FIG. 6A shows a detailed structure of one embodiment of the accessor  30  explained with reference to FIG. 5. The accessor  30  can accommodate and convey only one cartridge  10  as explained with reference to FIG. 4, and has a hand mechanism section (to be described later) that holds the cartridge  10 , inside the accessor  30 . The cartridge  10  is inserted into an insertion hole  39  provided on one of longitudinal side surfaces of the accessor  30 , and is pulled toward the inside of the accessor  30  with the hand mechanism section. A screw insertion hole  33  for passing through the ball screw  24  is provided on the upper portion of the accessor  30 . A moving mechanism  32  of a hand mechanism section  40 , to be described later, is provided at a position adjacent to this screw insertion hole  33 . This moving mechanism  32  is driven with a motor  31  provided on the upper portion of the accessor  30 .  
         [0059]    [0059]FIG. 6B shows an internal structure of the automatic changer shown in FIG. 6A, with a side wall  36  adjacent to this insertion hole  39  removed from the automatic changer. In an internal space  44  that continues from the insertion hole  39  of the accessor  30 , there is provided the hand mechanism section  40  that holds a cartridge  10 , pulls the cartridge  10  into the accessor  30 , and releases the cartridge  10  from the accessor  30 . Two holding arms  41  are provided on the hand mechanism section  40  in projection to the insertion hole  39  side, and a condenser lens  43 , to be described later, is provided at the center of the hand mechanism section  40 .  
         [0060]    The hand mechanism section  40  is structured to be able to move along two guide rails  37  provided on a floor surface  45  of the internal space  44  of the accessor  30 . An arm  35  that is driven by the motor  31  and the moving mechanism  32  is provided on this floor surface  45 . The hand mechanism section  40  can move on the guide rail  37  based on the move of this arm  35 . A fitting base  34  of the arm  35  is rotated by the moving mechanism  32 . A CCD  38  is provided in the internal space  44  of a side wall  46  that is at the opposite side of the insertion hole  39  of the hand mechanism section  40 . This CCD  38  is provided on the moving axis line of the condenser lens  43  provided in the hand mechanism section  40 .  
         [0061]    [0061]FIG. 6C shows a status that the hand mechanism section  40  shown in FIG. 6B has moved to a position of reading a bar code adhered to a magnetic tape cartridge not shown. In this status, the condenser lens  43  focuses the image of the bar code positioned at the front within a readable range shown by broken lines on the CCD  38 . Therefore, the CCD  38  can read the bar code.  
         [0062]    [0062]FIG. 7 shows a state of FIG. 6C together with the cartridge  10 . FIG. 7 shows the driving mechanism of the hand mechanism section  40  in detail. A pin sliding groove  42  is provided in the hand mechanism section  40  in its longitudinal direction. A pin  35 P provided in projection on the front end of the arm  35  is slidably engaged with this pin sliding groove  42 . Therefore, when the arm  35  rotates based on the rotation of the motor  34 , the pin  35 P at the front end of the arm  35  moves by sliding within this pin sliding groove  42 . Consequently, the hand mechanism section  40  moves within the internal space  44  in a direction shown by a thick arrow along the guide rail  37  of the hand mechanism section  40 . Then, in a state where the hand mechanism section  40  is stationary at a position shown in the drawing, the condensing lens  43  focuses the image of the bar code label  15  adhered to the side surface of the cartridge  10  on the CCD  38 . As a result, the CCD  38  reads the bar code printed on this bar code label  15 . The circuit installed on the main board  29 , that is explained with reference to FIG. 5, decodes the bar code that has been read by the CCD  38 .  
         [0063]    [0063]FIG. 8A shows a state where the hand mechanism section  40  shown in the state of FIG. 7 has moved to the insertion hole  39  side, and the holding arm  41  holds the cartridge  10 . When the arm  35  has rotated to the insertion hole  39  side based on the rotation of the motor  34 , the hand mechanism section  40  becomes in a state where it has moved to the nearest position of the insertion hole  39 . In this state, the holding arm  41  stretches from the accessor  30 , and holds the cartridge  10 . When the motor  31  rotates in the state where the hand mechanism section  40  is stationary at a position shown in the drawing, and when the arm  35  rotates to the CCD  38  side, the hand mechanism section  40  moves to the internal space  44  side as shown in FIG. 8B, and the cartridge  10  is accommodated into the accessor  30 .  
         [0064]    The state of FIG. 8B is the same as the state shown in FIG. 5A. In the state where the accessor  30  accommodates the cartridge  10 , the accessor  30  moves within the automatic changer  1  based on the rotation of the ball screw  24 , conveys the accommodated cartridge  10  to the drive  27 , and sets the cartridge  10  to the drive  27 . Based on the above operation, the accessor  30  of the present invention can read and understand the contents of the bar codes of the cartridges  10  that are accommodated in the cells  21  of the magazine  20  and in the fixed holder  26  provided within the automatic changer  1 . Further, the accessor  30  can hold the cartridges  10  that are accommodated in the cells  21  of the magazine  20  or in the fixed holder  26 , and convey the cartridges  10  to the driver  27 . The accessor  30  can return the cartridges  10  in the drive  27  to the magazine  20  or the fixed holder  26 .  
         [0065]    As explained above, according to the present invention, the CCD  38  is provided within the cartridge accommodation space  40  of the accessor  40 , and the condensing lens that focuses the image of the bar codes on the CCD is incorporated in the hand mechanism section  40 . Therefore, there is no portion that projects from the main body toward the outside, unlike the conventional bar-code reader and automatic changer, and it becomes possible to reduce the size of the accessor  30 . As a result, a distance over which the accessor  30  can move within the automatic changer  1  increases, and it becomes possible to accommodate more cartridges  10  than usual. While the automatic magnetic-tape changer  1  of the present embodiment can accommodate eleven cartridges  10 , the conventional automatic changer of the same sizes can accommodate only seven to eight cartridges  10 .  
         [0066]    [0066]FIG. 9A shows another embodiment of a magnetic-tape cartridge  10 A that is used in the automatic changing of the present invention. A bar code adhesion area  11 A is provided on the side surface of the cartridge  10 A. A bar code label  15 A described with a bar code as shown in FIG. 9B is adhered to the bar code adhesion area  11 A of the cartridge  10 A. FIG. 9C shows still another embodiment of a magnetic-tape cartridge  10 B that is used in the automatic changing of the present invention. A bar code adhesion area  11 B is provided on the side surface of the cartridge  10 B. A bar code label  15 B described with a bar code as shown in FIG. 9D is adhered to the bar code adhesion area  11 B of the cartridge  10 B. It is possible to recognize volume numbers and the contents of the volumes of the cartridge  10 A and  10 B, by reading the bar codes printed on the bar code labels  15 A and  15 B respectively.  
         [0067]    In the above embodiments, magnetic-tape cartridges have been explained as recording media that are incorporated in the automatic changer. However, the recording media are not particularly limited to magnetic tapes, and any recording medium that is accommodated in a cartridge can be used as the recording medium to be incorporated in the automatic changer. For example, as cartridges that can be used in the automatic changer of the present invention, there are MO (magnetic optical) cartridges that use optical disks, cartridges that accommodate DVDs (digital versatile disks) or MDs (mini disks), and stick-shaped cartridges that incorporate non-volatile IC memories.  
         [0068]    As explained above, according to the automatic changer of the present invention, the image pick-up member that reads an identifier attached to a cartridge and recognizes this cartridge, and the condenser lens, are provided within the casing and the hand mechanism of the accessor respectively. Therefore, the image pick-up member and the condenser lens do not stretch out from the accessor, and it becomes possible to make the accessor compact. As a result, there is an effect that it is possible to reduce the sizes of the automatic changer and increase the number of cartridges that can be accommodated within the automatic changer, without changing the size of the automatic changer.