Abstract:
A tape cartridge system and a method of operating a tape cartridge system are provided. The tape cartridge system includes a cartridge housing, a reel provided in the cartridge housing, a magnetic tape wound about the reel, a cartridge buckle assembly provided at one end of the magnetic tape, and a buckle retainer provided in the cartridge housing having at least one clamping member for releasably retaining the cartridge buckle assembly. The method includes rotating a reel in a tape cartridge to wind a magnetic tape around the reel until a cartridge buckle assembly provided at one end of the magnetic tape contacts a buckle retainer provided in the tape cartridge, and coupling the cartridge buckle assembly with the buckle retainer by continuing to rotate the reel until the cartridge buckle assembly is releasably retained by the buckle retainer.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    Tape drives are widely used for storing information in digital form. An exemplary tape drive system  100  is shown in FIG. 1. These tape drive systems  100  commonly use a storage tape  126  having a thin film of magnetic material which receives the information. Typically, the storage tape is moved between a pair of spaced apart reels  117  and  124 , past a data transducer  116  to record or read back information from the storage tape  126 .  
           [0002]    In one type of tape drive system, one of the reels  117  is part of a tape drive  112  while the other reel  124  is part of a removable tape cartridge  114 . For this type of tape drive system  100 , the reel  117  which is a part of the tape drive  112  is commonly referred to as a take-up reel  117 , while the reel  124  which is a part of the tape cartridge  114  is commonly referred to as a cartridge reel  124 . With this system  100 , upon insertion of the cartridge  114  into the tape drive  112 , the storage tape  126  on the cartridge reel  124  is coupled to the take-up reel  117  of the tape drive  112 . Subsequently, prior to removing the tape cartridge  114  from the tape drive  112 , the storage tape  126  is rewound onto the cartridge reel  124  and is then uncoupled from the take-up reel  117 .  
           [0003]    Due to the precise mechanical nature of coupling and uncoupling of the magnetic tape  126  from the take-up reel  117 , errors can sometimes occur when the various coupling components are out of place. These errors can be the result of, for example, excessive or insufficient winding of the storage tape  126  around the cartridge reel  124 , which can be caused by jostling of the tape cartridge  114 . It, is desirable to provide a tape drive system where the tape cartridge  114  can be reliably coupled with the tape drive  112 .  
         BRIEF SUMMARY OF THE INVENTION  
         [0004]    In accordance with embodiments of the present invention, a tape cartridge system is provided. The tape cartridge system comprises a cartridge housing, a reel provided in the cartridge housing, a magnetic tape wound about the reel, a cartridge buckle assembly provided at one end of the magnetic tape, and a buckle retainer provided in the cartridge housing having at least one clamping member for releasably retaining the cartridge buckle assembly.  
           [0005]    In accordance with other embodiments of the present invention, a method of operating a tape cartridge system is provided. The method comprises rotating a reel in a tape cartridge to wind a magnetic tape around the reel until a cartridge buckle assembly provided at one end of the magnetic tape contacts a buckle retainer provided in the tape cartridge, and coupling the cartridge buckle assembly with the buckle retainer by continuing to rotate the reel until the cartridge buckle assembly is releasably retained by the buckle retainer.  
           [0006]    In accordance with other embodiments of the present invention, a buckle retainer for use in a tape cartridge having a cartridge housing, a magnetic tape wound about a cartridge reel provided in the cartridge housing, and a cartridge buckle assembly provided at one end of the magnetic tape. The buckle retainer comprises a mounting portion for mounting the buckle retainer in the cartridge housing; and a clamping member having at least one flexible flange for releasably retaining the cartridge buckle assembly.  
           [0007]    Other features and aspects of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the features in accordance with embodiments of the invention. The summary is not intended to limit the scope of the invention, which is defined solely by the claims attached hereto.  
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)  
       [0008]    [0008]FIG. 1 is a tape drive system in accordance with embodiments of the present invention.  
         [0009]    [0009]FIGS. 2A-2B are perspective views of a cartridge leader and a take-up leader in accordance with embodiments of the present invention.  
         [0010]    [0010]FIGS. 3A-3C are side views of a cartridge buckle assembly.  
         [0011]    [0011]FIG. 4 is a perspective view of a buckle retainer in accordance with embodiments of the present invention.  
         [0012]    [0012]FIGS. 5A-5B are-front and rear perspective views of a buckle retainer mounted in a cartridge housing in accordance with embodiments of the present invention.  
         [0013]    [0013]FIGS. 6A-6B are top views bf a buckle retainer mounted in a cartridge housing in accordance with embodiments of the present invention.  
         [0014]    [0014]FIGS. 7A-7B are cross-sectional side views of a buckle retainer mounted in a cartridge housing in accordance with embodiments of the present invention.  
         [0015]    [0015]FIGS. 8A-8B are additional side views of a buckle retainer mounted in a cartridge housing in accordance with embodiments of the present invention.  
         [0016]    [0016]FIG. 9 is a tape library in accordance with embodiments of the present invention.  
         [0017]    [0017]FIG. 10 is a perspective view of a buckle retainer in accordance with other embodiments of the present invention. 
     
    
       [0018]    In the following description, reference is made to the accompanying drawings which form a part thereof, and which illustrate several embodiments of the present invention. It is understood that other embodiments may be utilized and structural and operational changes may be made without departing from the scope of the present invention. The use of the same reference symbols in different drawings indicates similar or identical items.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0019]    [0019]FIG. 1 shows a tape drive system  100  having a tape drive  112  and a tape cartridge  114 . The tape drive  112  includes a drive housing  115 , a data transducer  116 , a take-up reel  117 , a take-up leader  118  connected to the take-up reel  117 , a tape cartridge receiver  120 , and a buckling device  122 . The tape cartridge  114  includes a cartridge housing  119 , a cartridge reel  124 , a magnetic tape  126 , and a cartridge leader  128 . The drive housing  115  contains the various components of the tape drive  112 . The data transducer  116  transfers information to and from the storage tape  126 . A plurality of tape rollers  138  can be used for guiding the storage tape  126  from the cartridge reel  124  past the data transducer  116  and onto the take-up reel  117 . The tape cartridge receiver  120  is adapted to receive the cartridge  114 .  
         [0020]    In operation, the buckling device  122  couples the cartridge leader  128  on the storage tape  126  to the take-up leader  118  during loading of the tape cartridge  114  into the tape drive  112 . The process of connecting the take-up leader  118  with the cartridge leader  128  is commonly referred to as “coupling” or “buckling”. Subsequently, during ejection of the tape cartridge  114 , the buckling device  122  unbuckles the cartridge leader  128  from the take-up leader  118 .  
         [0021]    [0021]FIG. 2A is a close-up view of an exemplary cartridge leader  128  uncoupled from a take-up leader  118 . FIG. 2B illustrates the cartridge leader  128  coupled to the take-up leader  118 . The tape cartridge leader  128  includes a cartridge buckle assembly  200  having a pair of receiver arms  202  mounted on distal ends of a buckle pin  204 . The end of the magnetic tape  126  is attached to the tape cartridge leader  128  via splice  127 . Each receiver arm  202  includes a slot  206  and the take-up leader  118  includes a leader pin  210  configured to fit into the slots  206 . During the buckling process, the buckling device  122  draws the take-up leader  118  to the cartridge leader  128  and inserts the distal ends of the leader pin  210  into the slots  206  in the receiver arms  202 . When the ends of the leader pin  210  reach the ends  208  of the slots  206 , the take-up leader  118  is fully engaged with the cartridge leader  128 . At this point, the take-up reel  117  draws the take-up leader  118  and the cartridge leader  128  through the tape drive  112  and onto the take-up reel  117 . Exemplary systems incorporating a cartridge leader and take-up leader are described in greater detail in U.S. Pat. No. 5,971,310, to Saliba et al., incorporated by reference herein in its entirety.  
         [0022]    Before the tape cartridge  114  is removed from the tape drive  112 , the magnetic tape  126  is rewound about the tape cartridge reel  124  and then the cartridge buckle assembly  200  is uncoupled from the take-up leader  118 . During normal operation, when the magnetic tape  126  is fully rewound, the tension in the tape  126  retains the cartridge buckle assembly  200  against a pair of shoulders  300  provided in the tape cartridge housing  119 , as shown in FIG. 3A. This is known as the “home” position for the cartridge buckle assembly  200 . The tape cartridge  114  can then be removed and stored separately from the tape drive  112 . The next time the tape cartridge  114  is inserted into the tape drive  112 , the buckling device  122  is configured to try to couple the take-up leader  118  with the cartridge leader  128  assuming that the cartridge buckle assembly  200  is properly located in the home position.  
         [0023]    In some situations, the tape cartridge  114  may be jostled or undergo some impact causing the tape cartridge reel  124  to rotate, thereby unwinding the magnetic tape  126 . This may cause the cartridge buckle assembly  200  to become disengaged from the shoulders  300  and leave the home position. Then, the next time the tape drive  112  attempts to perform a buckling operation, because the cartridge buckle assembly  200  is not in the expected location, the buckling device  122  may not be capable of properly engaging the leader pin  210  with the slots  206  of the cartridge leader  128 . This results in a “misbuckle,” which may prevent the tape drive  112  from loading the tape cartridge  114 .  
         [0024]    In other situations, the tape cartridge reel  124  may rotate in the opposite direction causing the magnetic tape  126  to be overwound. This may occur, for example, if too much torque is applied to the tape cartridge reel  124  during the rewind process. In this case, the cartridge buckle assembly  200  may be pressed against the shoulders  300 , as shown in FIG. 3C. Here, the tension provided by the tape leader  128  onto the central portion of the buckle pin  204  is opposed by the force imparted by shoulders  300  onto the receiver arms  202 , thereby causing the buckle pin  204  to bend. As a result of this bending, the distal ends of the receiver arms  202  opposite the buckle pin  204  may be drawn closer together. This effect may be referred to as “toeing in.” Accordingly, the ends  208  of the slots  206  in the receiver arms  202  are also drawn closer together.  
         [0025]    When the receiver arms  202  are toed in, various problems may arise. The next time a buckling operation is performed, the leader pin  210  may be too wide to be fully received between the slots  206  of the compressed receiver arms  202 . This may result in an immediate misbuckle error, thereby causing an interrupt in the loading operation. Even more dangerously, if the leader pin  210  is partially received into the slots  206 , the buckling device  122  may not recognize that the buckling is incomplete and the tape drive  112  may continue with the winding of the magnetic tape  126  around the tape-up reel  117 . When the leader pin  210  is not fully engaged with the slots  206 , the take-up leader  118  may under certain circumstances become unbuckled from the cartridge leader  128  before the cartridge leader  128  has been pulled onto the take-up reel  117 . This is commonly referred to as “leader runaway”. When a leader runaway occurs, the tape drive may become completely inoperable and must be manually serviced to remove the tape cartridge  114 . During this time, the user cannot access to the information on the storage tape  114  and the tape drive  112  cannot be used to read any other tapes.  
         [0026]    In accordance with aspects of the present invention, a buckle retainer is provided for releasably retaining the buckle assembly  200  when the buckle assembly  200  is not buckled with the take-up reel  117 .  
         [0027]    [0027]FIG. 4 is a perspective view of a buckle retainer  400 , in accordance with embodiments of the present invention. The buckle retainer  400  includes a pair of clamping members  402   a - 402   b  extending from the body  404  of the retainer  400 , and a pair of mounting portions  408   a - 408   b . The mounting portions  408   a - 408   b  of the buckle retainer  400  can be used to mount the retainer  400  in the cartridge housing  119 , as shown in FIGS. 5A-5B. Each of the clamping members  402   a - 402   b  include a pair of opposing flexible flanges  410   a - 410   d . Each pair of flexible flanges  410  define a enlarged retaining region  412  for receiving a portion of the buckle assembly  200 , and an opening  414  of reduced size through which the portion of the buckle assembly  200  passes as the portion is inserted into the retaining region.  
         [0028]    A typical tape cartridge housing  119  is formed out of a pair of top and bottom shells that are mated together with the cartridge reel  124  and magnetic tape  126  provided therebetween. FIG. 5A is a front perspective view of the buckle retainer  400  mounted in the bottom shell  500   a  of the tape cartridge housing  119 . The top shell  500   b  is omitted from FIGS. 5A-5B for clarity, but is shown in FIGS. 7A-7B and  8 A- 8 B. FIG. 5B is a rear perspective view of the buckle retainer  400  mounted in the bottom shell  500   a . In FIGS. 5A-5B, the buckle assembly  200  is shown as being coupled with the buckle retainer  400 , while the tape leader  128  coupled to the buckle assembly  200  is not shown for clarity. The cartridge housing  119  is configured with a pair of mounting regions (only the bottom mounting region  502  in the bottom shell  500   a  is shown) for mating with the mounting portions  408   a - 408   b  of the buckle retainer  400 .  
         [0029]    [0029]FIGS. 6A-6B are top views of the buckle retainer  400 , the buckle assembly  200 , and the tape leader  128 . FIG. 7A is a side view of the tape cartridge  114  along line A-A in FIG. 1, and FIG. 7B is a close-up view of the region X of FIG. 7A. FIG. 8A is a side view of the tape cartridge  114  along line B-B, and FIG. 8B is a close-up view of the region Y.  
         [0030]    In accordance with embodiments of the present invention, the buckle retainer  400  is provided for releasably retaining the cartridge buckle assembly  200 . When the cartridge reel  124  is rewound, the magnetic tape  126  draws the leader buckle assembly  200  back into the tape cartridge  114 , as shown in FIG. 6A. As the cartridge reel  124  continues to rotate, the buckle pin  204  is drawn into the clamping members  402   a - 402   b , which releasably retain the buckle pin  204 . In the illustrated embodiment, the clamping members  402   a - 402   b  include a pair of flexible flanges or fingers having a gap therebetween for receiving the buckle pin  204 . When the buckle assembly  200  is coupled with the buckle retainer  400 , the buckle pin  204  is received into the gap and is retained in place by the clamping members  402 , as shown in FIGS. 5A, 5B, and  6 B.  
         [0031]    In FIG. 6A, the buckle pin  204  is located at the opening  414  between the flexible flanges  410   a - 410   b . This opening  414  is smaller than the diameter of the buckle pin  204  and therefore provides some resistance to the buckle pin  204  as it is drawn into the retaining region  412  of the buckle retainer  400 . As the magnetic tape  126  continues to apply a tension to the buckle pin  204 , the flexible flanges  210   a - 210   b  flex and separate to enlarge the opening  414  to allow the buckle pin  204  to pass therethrough. Finally, the buckle pin  204  is received into the retaining region  412  and is releasably retained therein by the flexible flanges  210   a - 210   b , as shown in FIG. 6B.  
         [0032]    Once the buckle assembly  200  is coupled with the buckle retainer  400 , tension from the tape leader  128  is not required to maintain the buckle assembly  200  in the home position. Therefore, even if the tape cartridge  114  is jarred or handled roughly causing the cartridge reel  124  to unwind, the buckle assembly  200  continues to be retained in place by the clamping members  402 , despite any buildup of slack in the unwound magnetic tape  126 .  
         [0033]    The next time the tape cartridge  114  is loaded into the tape drive  112 , the buckling device  122  will be able to locate the buckle assembly  200  in the expected home position. When the buckling device  122  couples the take-up leader  118  with the buckle assembly  200 , the force provided by the take-up reel  117  on the take-up leader  118  is sufficient to pull the buckle pin  204  out of the clamping members  402 . The buckling process can proceed as described above.  
         [0034]    In accordance with embodiments of the present invention, the buckle retainer  400  is configured to releasably retain the buckle assembly  200 . By releasably retaining the buckle assembly  200 , the buckle retainer  400  provides a level of resistance to inhibit movement of the buckle assembly  200  from the home position. In the embodiment described above, the retaining force provided by the flexible flanges  410  of the clamping members  402  is sufficient to retain the buckle assembly  200  in the retaining region  412  in the event of a jarring force or other movement. However, during the buckling process, the force applied to the buckle assembly  200  by the buckling device  122  is sufficient to withdraw the buckle pin  204  from the clamping members  402 . The extent of the retaining force of the buckle retainer  400  can be varied by modifying the design of the clamp depending on&#39;the desired amount of resistance to movement.  
         [0035]    In accordance with embodiments of the present invention, the buckle retainer  400  may further include a support  406  to inhibit bending of the buckle pin  204  when the buckle assembly  200  is coupled with the buckle retainer  400 . In the illustrated embodiment, the support  406  protrudes from the body  404  of the retainer  400  at a point approximately midway between the clamping members  402   a - 402   b  and has a length such that the end of the support  406  abuts the buckle pin  204  when the buckle pin  204  is fully received in the clamping members  402   a - 402   b.    
         [0036]    As described above, under certain circumstances, the cartridge reel  124  may become overwound, thereby pulling the buckle assembly  200  deeper into the tape cartridge  114  beyond the home position. When the buckle assembly  200  is only supported at the distal ends of the buckle pin  204 , tension from the tape leader  128  applied to the buckle pin  204  between the supporting locations may cause bending of the buckle pin  204 , resulting in “toe in” of the receiver arms  202 . By providing the support  406  at a location between the distal supporting locations, bending of the buckle pin  204  can be avoided.  
         [0037]    In the illustrated embodiment, the support  406  is in the form of a protruding beam which abuts the buckle pin  204 . In other embodiments, the support  406  may be formed in a variety of shapes and lengths, depending on the design of the buckle assembly  200  and the attachment of the tape leader  128  to the buckle assembly  200 . In some embodiments, the support  406  may not abut the buckle pin  204  and may be separated from the pin  204  by a gap. This arrangement may be used where the buckle assembly  200  and/or the configuration of the attachment of the tape leader  128  to the buckle assembly  200  are such that a support which abuts the buckle pin  204  may be impractical, impossible, or otherwise undesirable. The gap may be sized such that a limited, acceptable amount of bending of the buckle pin  204  is permitted before the pin  204  abuts the support  406 .  
         [0038]    In the above described embodiments, the buckle retainer  400  does not include any pivoting, rotating, or movable parts, and uses only flexible flanges  410  to releasably retain the buckle assembly  200 . This design is in contrast with locking mechanisms that may require hinged locks or other mechanisms which must be actuated to either retain and/or release the buckle assembly  200  from the home position. An immobile buckle retainer  400  provides the function of retaining the buckle assembly  200  using a simple, fixed component. In some embodiments, the mounting portions  408   a - 408   b  in the buckle retainer  400  may be loosely coupled to the cartridge housing  119  such that the buckle retainer  400  may change position slightly during use in order to accommodate variations in the buckling process. In these embodiments, the buckle retainer  400  may still releasably retain the buckle assembly  200  using only flexible flanges and without requiring a moving locking mechanism.  
         [0039]    The tape drive systems  100  and tape drives  112  described above can be installed within a computer workstation or a tape library  900 , as shown in FIG. 9. The illustrated tape library  900  includes a plurality of tape cartridges  114  which are retained in a multiple cartridge magazine  902 , a robotic cartridge handler  904 , and a pair of tape drives  112 . The robotic cartridge handler  904  is used to selectively retrieve one of the tape cartridges  114  from the cartridge magazine  902  and place the tape cartridge  114  into one of the tape drives  112 . A representative tape library  900  is the ATL P7000 by Quantum Corporation.  
         [0040]    While the invention has been described in terms of particular embodiments and illustrative figures, those of ordinary skill in the art will recognize that the invention is not limited to the embodiments or figures described. For example, the buckle retainer  400  described above is formed as a separate component that is mounted into the cartridge housing  119 . Because the buckle retainer  400  is formed as a separate component, the retainer  400  can be manufactured using different materials and/or manufacturing processes than the cartridge housing  119 . This can facilitate the formation of fine, precise features on the buckle retainer  400 . In other embodiments, the buckle retainer can be integrally formed with the housing. In one embodiment, both the buckle retainer  400  and the cartridge housing  119  are separately formed of plastic by injection molding. The buckle retainer  400  is then retained between the two clamped halves forming the cartridge housing  119 . In other embodiments, the cartridge housing  119  can be made of injection molded plastic, while the buckle retainer  400  can be made of, for example, steel or machined metal.  
         [0041]    In the illustrated embodiments, the buckle pin  204  is a roughly cylindrical stainless steel pin connecting the two retaining arms  202 . In other embodiments, the buckle pin  204  need not be in the shape of a pin. For example, the buckle pin may be formed as a rectangular member connecting the two retaining arms.  
         [0042]    In the embodiments described above, the buckle retainer  400  includes a pair of clamping member  402   a - 402   b , which engage the buckle pin  204  near the distal ends of the buckle pin  204 . In other embodiments, the buckle assembly  200  may be releasably retained by the buckle retainer using a different configuration. In the embodiment illustrated in FIG. 10, for example, a single clamping member  402 ′ may be provided for clamping the buckle pin  204 . In some embodiments, shoulders  300 , as shown in FIGS. 3A-3B, may be used to abut the ends of the buckle assembly  200  and the single clamping member  402 ′ may be provided midway between the shoulders  300 . Accordingly, the single clamping member  402 ′ may simultaneously provide the functions of releasably retaining the buckle assembly  200  and inhibiting bending of the buckle pin  204 . In yet other embodiments, the clamping member  402 ′ may include only a single flexible flange for releasably retaining the buckle assembly  200 . This may be implemented by using a single flexible flange works in conjunction with a stationary, inflexible member to provide a compressive retaining force on the buckle assembly  200 .  
         [0043]    In addition, the methods and steps described above indicate certain events occurring in a certain order. Those of ordinary skill in the art will recognize that the ordering of certain steps may be modified, and that such modifications are in accordance with the various embodiments of the invention. Additionally, certain of the steps may be performed concurrently in a parallel process when possible, as well as performed sequentially as described above.  
         [0044]    Therefore, it should be understood that the invention can be practiced with modification and alteration within the spirit and scope of the appended claims. The description is thus to be regarded as illustrative instead of limiting on the invention.