Abstract:
A tape cartridge including a tape capable of recording and reproducing a high accuracy servo signal, by preventing a deformation of the tape by preventing turning up of a front end portion of a tape when the front end portion is adhered to a reel hub. The tape cartridge includes the tape, a single reel having a reel hub around which the tape is wound and a cartridge case in which the reel is installed, and the front end portion of the tape is adhered to the reel hub, and each corner of the front end portion of the tape is chamfered and chamfers are formed.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the foreign priority benefit under Title 35, United States Code, §119(a)-(d) of Japanese Patent Application No. 2006-166599 filed on Jun. 15, 2006 in the Japan Patent Office, the disclosure of which is herein incorporated by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a tape cartridge of a single reel type. 
         [0004]    2. Description of the Related Art 
         [0005]    Conventionally, in a single reel type tape cartridge, a tape has been wound around a hub of a reel contained in a cartridge case at the last stage of assembly. Since it is necessary to adhere one end portion (a front end portion) of the tape stably to the hub when winding starts, in order to wind the tape soundly around the hub, various methods for adhering the tape to the hub have been proposed. Hereunder, the adhering methods are described, referring to  FIG. 7  and  FIG. 8 .  FIG. 7A  shows a cross-section of a transport means for a tape front end;  FIG. 7B  is a plane view of the transport means for the tape front end, viewing  FIG. 7A  along a direction A;  FIG. 7C  is a view illustrating a condition of adhering a tape around a hub after the state of  FIG. 7A ; and  FIG. 7D  is a side view viewing  FIG. 7C  along a direction B.  FIG. 8A  and  FIG. 8B  are views, illustrating a conventional tape cartridge, wherein  FIG. 8A  is a plane view of a tape reel and  FIG. 8B  is an enlarged view of a deformed part of a tape wound to a tape reel. 
         [0006]    For example, a tape winder described in Japanese Laid-open Patent Application No. 2004-70005, includes a cartridge support unit which holds a cartridge containing a reel without a magnetic tape (tape hereinafter) wound thereon, and a tape introduction unit which introduces a tape into the cartridge. Referring to  FIGS. 7A to 7D , the tape introduction unit  122  includes a suction part where a tape MT is sucked, and an applicator  128  where a liquid such as alcohol is applied to a hub surface of the reel, as shown in  FIG. 7  A and  FIG. 7B , respectively. Further, flanges  105 A (omitted in  FIG. 7C) and 105B  are placed along both sides of a hub H, as shown in  FIG. 7C  and  FIG. 7D . Then, through inserting the tape introduction unit  122  sucked with the front end of the tape MT into the inside of the cartridge, the tape winder applies alcohol along the hub surface using the applicator  128 , firstly. Then, the tape winder adheres the tape MT to the hub, by contacting the tape to the hub surface applied with alcohol. Then, the tape winder winds up the tape MT around the hub, by rotating a reel CR (refer to  FIG. 8 ) in a reel drive unit. 
         [0007]    A front end portion of a tape may sometimes turn up over the hub when the tape is adhered to the hub, due to a difference in stretch properties between an upper face and a lower face, or due to core set. Therefore, according to the tape winder described in Japanese Laid-open Patent Application No. 2004-70005, if either an amount or a width of alcohol being applied is not satisfactory, the front end corner  125  of the tape MT may turn up as shown in  FIG. 7C  and  FIG. 7D , because the front end portion of the tape MT would not be adhered completely to the surface of the hub H. 
         [0008]    If the front end corner  125  turns up when the tape MT is adhered to the hub H, a small crevice S for the turned-up height of the front end corner  125  may be formed between the hub H and the tape MT, as illustrated in the enlarged view of part A in  FIG. 8 . Due to the winding force of the tape, accumulated with increasing winding turns of the tape over the crevice S, the crevice S will collapse and then small surface waviness will be formed in the vicinity of the crevice S, which will bring a radial deformation along a radial direction of the tape. 
         [0009]    This radial deformation of the tape MT has been a cause of some error such as recording miss which appears in magnetic record reproduction, because of the instability of track positioning which is generated by variation of the tape position along width direction when feeding the tape from the reel CR. 
       SUMMARY OF THE INVENTION 
       [0010]    The present invention seeks to provide a tape cartridge capable of recording and reproducing record of a high accuracy servo signal, by preventing a deformation of a wound up tape through preventing turning up of a front end portion of a tape when the front end portion of the tape is adhered to a hub. 
         [0011]    A tape cartridge according to the present invention, which resolves the foregoing drawbacks of the prior art comprises a tape; a single reel having a hub around which a tape is wound; and a cartridge case in which the reel is housed, wherein a front end portion of the tape is adhered to the hub, and a chamfered portion is formed at each corner of the front end portion of the tape by being chamfered. 
         [0012]    According to the present invention, turning up of the front end portion of the tape can be prevented while the tape being wound around the hub, thanks to the chamfered portion formed at each corner of the front end portion of the tape. In this way, the radial deformation of the tape can be prevented, because the tape can be adhered stably to the hub. 
         [0013]    The chamfered portions can be an arc shape. 
         [0014]    With this design, the tape can be adhered stably to the hub, because no corner remains in the front end portion of the tape thanks to the arc shaped chamfered portions. 
         [0015]    Each chamfered portion may be straight and makes an angle of 45 degrees to each side of the tape. 
         [0016]    With this design, the tape can be adhered more stably to the hub, preventing turning up of the front end portion of the tape over the reel hub, because each corner is not so sharp and is properly chamfered. 
         [0017]    The chamfered portions may be formed in one third width of the tape full width, respectively. 
         [0018]    With this design, the tape can be adhered stably to the hub, because the front end portion of the tape does not have a so sharp portion, because of the configuration in which right and left corner chamfered portions and center portion of the front end portion of the tape have one third width of the tape full width, respectively. 
         [0019]    Other features and advantages of the present invention will be apparent from the following description. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    An embodiment of the present invention will be described in detail based on the following drawings, wherein: 
           [0021]      FIG. 1  is an exploded perspective view of a tape cartridge according to a first embodiment of the present invention; 
           [0022]      FIG. 2A  is an exploded perspective view illustrating a reel part in  FIG. 1 . 
           [0023]      FIG. 2B  is an enlarged view of a front end portion of a tape adhered to a reel hub; 
           [0024]      FIG. 3  is a schematic block diagram illustrating a tape winder for manufacturing the tape cartridge according to the first embodiment; 
           [0025]      FIG. 4  is a plane view, illustrating a main part of a transport unit for the front end portion of the tape which retains the tape by sucking according to the first embodiment; 
           [0026]      FIG. 5  is a view illustrating operation of a tape adhering unit in the tape cartridge according to the first embodiment; 
           [0027]      FIG. 6A  is a plane view and an enlarged view of a part, of the main part of the transport unit of the front end portion of the tape which retains the tape to be sucked and wound around in the tape cartridge according to the second embodiment of the present invention; 
           [0028]      FIG. 6B  is a plane view and an enlarged view of the front end portion of the tape having arc shaped chamfered portions to be sucked and wound around in the tape cartridge according to the second embodiment of the present invention; 
           [0029]      FIG. 7A  is a cross-sectional view of a transport unit for the front end portion of the tape; 
           [0030]      FIG. 7B  is a plane view of the transport unit for the front end portion of the tape, viewing  FIG. 7A  along a direction A; 
           [0031]      FIG. 7C  is a view illustrating the condition of adhering the tape around the hub after the state of  FIG. 7A ; 
           [0032]      FIG. 7D  is a side view viewing  FIG. 7C  along a direction B. 
           [0033]      FIG. 8A  and  FIG. 8B  are views illustrating a conventional tape cartridge, wherein  FIG. 8A  is a plane view of a tape reel, and  FIG. 8B  is an enlarged view of a deformed part of the tape wound around the tape reel. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0034]    Embodiments of a tape cartridge according to the present invention will be described in detail with reference to the accompanying drawings. 
       First Embodiment 
       [0035]    A configuration of a tape cartridge  1  according to the present invention will be described, firstly. 
         [0036]    The tape cartridge  1  of  FIG. 1  conforms to the so-called LTO (Linear Tape-Open) standard and includes, in a cartridge case C divided to an upper half C 1  and a lower half C 2 , a single reel CR; a lock plate  2  and a compressive coil spring  3  for locking a rotation of the reel CR; a release pad  4  for releasing a lock of the reel CR; a hub H around which a tape MT is wound; a flange  5  including an upper flange  5 A and a lower flange  5 B welded to the hub H; a slide door  6  which opens and closes a tape-pull-out opening C 3  provided across the lower half C 2  and the upper half C 1  in the cartridge case C; a torsion coil spring  7  which pushes the slide door  6  to a closing position of a tape-pull-out opening C 3 ; a safety lug  8  for preventing erroneous erasure; a cartridge memory chip  9 ; a reel pin RP; and a clip  11 .  FIG. 1  illustrates a state where the tape MT is wound in the reel CR. 
         [0037]    Next, a detailed description is given on the tape MT, referring to  FIG. 2A  and  FIG. 2B . 
         [0038]    As illustrated in  FIG. 2A , a front end portion MT 1  of the tape MT is adhered to a surface of the hub H, and then the tape MT is wound around. 
         [0039]    Here, a description will be given on a configuration of the reel CR for the tape MT, especially on a configuration of the hub H and the flange  5  fixed to the hub H. 
         [0040]    The front end portion MT 1  of the tape MT is adhered to and wound around the hub H with a cylindrical shape. 
         [0041]    The flange  5  with a disk shape (refer to  FIG. 1 ) is composed of a hard material such as plastics, and includes the upper flange  5 A and the lower flange  5 B. The upper flange  5 A and the lower flange  5 B are placed at one end and at the other end of the cylindrical shape hub H respectively, both perpendicularly placed to a rotating axis of the hub H. 
         [0042]    The lower flange  5 B and the hub H are integrally molded. The upper flange  5 A and the hub H are fixed using any known method of a ultrasonic welding, an adhesive bonding, etc. 
         [0043]    The upper flange  5 A has an opening at its center portion. 
         [0044]    As illustrated in  FIG. 2B , chamfered portions  25 ,  25  are formed by chamfering each corner of the front end portion MT 1  of the tape MT to be adhered to the hub H. 
         [0045]    Each of the chamfered portions  25 ,  25  is straight and makes an angle θ to each side of the tape (45 degrees in the first embodiment, for example), respectively. 
         [0046]    It is preferable to form right and left corner chamfered portions  25 , in one third width of the full width of the tape MT, taking into consideration a balance between the chamfered portions  25 ,  25  and the front end portion MT 1 . 
         [0047]    At this time, an edge angle (not illustrated) of a tape cutter  80  (refer to  FIG. 3 ) described later is pre-adjusted, so that each chamfered portion is straight and form an angle of 45 degrees to each side of the tape MT. 
         [0048]    Next, a description is given on a configuration of a tape winder W for manufacturing a tape cartridge  1  according to the first embodiment. 
         [0049]      FIG. 3  illustrates an outline of a configuration of the tape winder W for manufacturing the tape cartridge  1  according to the first embodiment. 
         [0050]    The tape winder W illustrated in  FIG. 3  winds up the tape MT in a pancake shape in the reel CR, around the hub H of the reel CR installed in the cartridge case C, after cutting the tape MT to a pre-determined length. A tape adhering unit  20  for adhering the front end portion MT 1  of the tape MT to the hub H of the reel CR installed in the cartridge case C is disposed in the tape winder W. 
         [0051]    As illustrated in  FIG. 3 , the tape winder W mainly includes a tape supply unit  10 ; a tape adhering unit  20 ; a blade unit for polishing a surface of the tape MT; a cleaning units  40 ,  40  for cleaning both surfaces of the tape MT; a tension adjusting unit  50  for adjusting a tension of the running tape MT; a cartridge case supply part  60  for supplying the stocked cartridge case C to the tape adhering unit  20 ; a cartridge discharge port  70  which discharges the cartridge case C with the tape MT wound up by the reel CR thereof; and a tape cutter  80  for cutting the tape MT, which is placed in an upstream side of the tape adhering unit  20  in a running direction of the tape MT to. 
         [0052]    A plurality of tape guides  90  are properly arranged in a panel P for guiding the tape MT to the tape adhering unit  20 . 
         [0053]    In the first embodiment, the tape adhering unit  20  has a function of winding up the tape MT around the hub H as well. 
         [0054]    A manipulation panel for operating the tape winder W is given by numeral “ 100 ” in  FIG. 3 . 
         [0055]    The tape supply unit  10  supplies the tape MT to the tape adhering unit  20 , including the reel R 1  and the reel R 2  to which the tape MT is wound in a pancake shape. The tape supply unit  10  supplies the tape MT toward the tape adhering unit  20 , by rotating a reel drive unit (not illustrated) at a pre-determined rotation speed. The tape adhering unit  20  can supply continuously the tape MT to the tape adhering unit  20 , by replacing one reel R 1  to the other reel R 2  when the tape MT in one reel R 1  is run out, because the two reels R 1  and R 2  are equipped. 
         [0056]    The tape adhering unit  20  adheres the front end portion MT 1  of the tape MT supplied from the tape supply unit  10  to the hub H of the reel CR in the cartridge case C, and further has a function winding the tape MT around the hub H. 
         [0057]    According to  FIG. 3 , the tape adhering unit  20  includes a case installation part  21  where the cartridge case C is installed and a tape-front-end-portion transport unit  22  which transports the tape MT supplied from the tape supply unit  10  to the cartridge case C. 
         [0058]    The case installation part  21  holds the cartridge case C, in a state where the tape-pull-out opening C 3  of the cartridge case C is turned to the tape-front-end-portion transport unit  22 . 
         [0059]    A tape cutter  80 , with an upper edge and a lower edge, cuts the tape MT along a junction line of the upper edge and the lower edge, and is turnably attached around an axis center so that the front end portion MT 1  of the tape MT is cut straightly in a direction which makes an angle of 45 degrees to each side of the tape MT, and so that the tape MT is cut in the width direction after a pre-determined length of the tape MT is wound up to the reel CR. 
         [0060]      FIG. 4  is a plane view of a main part of the tape-front-end-portion transport unit  22  in which the tape MT is sucked in the tape cartridge C according to the first embodiment. 
         [0061]    As illustrated in  FIG. 4 , the tape-front-end-portion transport unit  22  is a lengthwise long block. The tape-front-end-portion transport unit  22  is provided at a position displaced in a horizontal direction from the tape-pull-out-opening C 3  of the cartridge case C installed at the case installation part  21  (refer to  FIG. 3 ), and has a function of transporting the tape MT through sucking the vicinity of the front end portion MT 1  of the tape MT supplied from the tape supply unit  10 . Accordingly, the tape-front-end-portion transport unit  22  is designed to move from the tape-pull-out opening C 3  to the inside of the cartridge case C, by a drive mechanism utilizing such an air cylinder, etc., (not illustrated). 
         [0062]    On the upper side of the tape-front-end-portion transport unit  22 , a sponge mount part  23  and a suction part  24  are formed in turn from a front end (near the cartridge case C). 
         [0063]    A sponge  28  is mounted on a concave portion formed at the sponge mount part  23 . The sponge mount part  23  is configured so that, for example, alcohol (liquid) for adhering such as ethanol being supplied to inside thereof and accordingly, proper amount of alcohol permeates the sponge  28  constantly. 
         [0064]    The sponge  28  is a rectangular shape block with a height slightly larger than the depth of the sponge mount part  23 . The sponge  28  is used for applying alcohol to the hub H of the reel CR in the cartridge case C (refer to  FIG. 3 ). It is preferable that the sponge  28  is of a resistant (chemical resistant) type against chemicals such as alcohol. The sponge  28  easily applies alcohol to the surface of the tape MT even just after being immersed in alcohol, due to flexibility thereof even during a drying time. Moreover, the sponge  28  can be used repeatedly without getting deformed because of its chemical resistance. 
         [0065]    The suction part  24  has a plurality of open holes  24   a . These holes  24   a  are converged into one passage within the block of the tape-front-end-portion transport unit  22 , and a vacuum pump and a compressor through a hose, a switching valve and the like are connected to the passage. During transporting the tape MT, the holes  24   a  can suck the tape MT as illustrated in  FIG. 4 , wherein a vacuum pump is connected to the holes  24   a.    
         [0066]    Meanwhile, the holes  24   a  can blow the tape MT toward the hub H, by switching the valve to be connected to the compressor. 
         [0067]    Next, a manufacturing method of the tape cartridge  1  according to the first embodiment is described. 
         [0068]      FIG. 5  illustrates operations of the tape adhering unit  20  of the tape cartridge  1  according to the first embodiment. 
         [0069]    As illustrated in  FIG. 5A , firstly the tape MT is vacuum-sucked to the holes  24   a  of the suction part  24  (refer to  FIG. 4 ) by a vacuum pump (not illustrated). Then, the sponge  28  is contacted with the hub H in the cartridge case C by horizontally shifting the tape-front-end-portion transport unit  22 , as it is. Accordingly, a proper amount of alcohol is applied to the hub H by the sponge  28  permeated with alcohol. Then, alcohol can be applied on the circumference surface of the hub H by rotating thereof. 
         [0070]    As illustrated in  FIG. 5C , the tape-front-end-portion transport unit  22  is moved forward to a position where the suction part  24  is located below the hub H. The front end portion MT 1  of the tape MT is blown to the hub H, by supplying compressed air to the holes  24   a  (refer to  FIG. 3 ) after releasing the vacuum suction of the holes  24   a , while the tape-front-end-portion transport unit  22  is moved upward, by rotating the hub H. Since the chamfered portions  25 ,  25  are provided at each corner of the front end portion MT 1  of the tape MT, the tape MT is forced in accordance with the hub shape, while the alcohol applied to the hub spreads over the front end portion MT 1 , as illustrated in a right side enlarged part of  FIG. 5D . In this way, the front end portion MT 1  of the tape MT is adhered fitly along the hub H. 
         [0071]    Then, as shown in  FIG. 5E , the tape-front-end-portion transport unit  22  is slightly lowered and is retreated out from the cartridge case C. In this way, the adhering operation of the tape MT to the hub H finishes. 
         [0072]    Then, the tape MT is wound up in the reel CR, by driving to rotate the reel CR using a reel drive means (not illustrated). 
         [0073]    After the tape MT is wound up by a required amount, the tape cutter  80  (refer to  FIG. 3 ) cuts off the tape, and the tape cartridge  1  is discharged from a tape cartridge discharge port  70  (refer to  FIG. 3 ). 
         [0074]    At this time, the front end portion MT 1  of the tape MT is cut by the tape cutter  80  (refer to  FIG. 3 ) and the chamfered portions  25 ,  25  are formed, and the tape cartridge  1  is manufactured one by one, by adhering the front end portion MT 1  of the tape MT to the hub H of the next tape cartridge  1 . 
         [0075]    Accordingly, the following effect can be obtained in the first embodiment. 
         [0076]    The turning up of the front end portion MT 1  of the tape MT can be prevented and the tape MT can be wound up tightly to the reel CR, thanks to the chamfered portions formed at the front end portion MT 1  of the tape MT, even if the alcohol applied to the hub H volatilizes, or alcohol does not spread to each corner of the front end portion MT 1  due to an insufficient width of the alcohol being applied to the tape MT. Accordingly, the radial deformation of the wound up tape MT can be prevented. The turning up of the front end portion MT 1  of the tape MT can be prevented effectively, since the front end portion MT 1  of the tape MT has no sharp portion, thanks to the chamfered portions  25 ,  25  which are formed in such a manner that the chamfered portions  25 ,  25  and the center part at the front end portion MT 1  of the tape MT have each one third width of the full width of the tape MT. 
       Second Embodiment 
       [0077]    Next, a description will be made on a tape cartridge  1 ′ according to a second embodiment of the present invention. 
         [0078]    Since, in the tape cartridge  1 ′ according to the second embodiment, the shape of the front end portion MT 1  of the tape MT according to the first embodiment is changed only, the same symbols are used in the same configuration as those in the tape cartridge  1  according to the first embodiment, and a duplicated description will be omitted. 
         [0079]      FIG. 6A  is a plane view and a partial enlarged view of a part of the main part of the transport unit  22  of the front end portion MT 1 ′ of the tape MT which retains the tape to be sucked and wound around in the tape cartridge according to the second embodiment. 
         [0080]      FIG. 6B  is a plane view and an enlarged view of a front end portion MT 1 ′ of the tape MT having arc shaped chamfered portions to be sucked and wound around in the tape cartridge according to the second embodiment. 
         [0081]    As illustrated in  FIG. 6 , in the tape MT of the tape cartridge  1 ′ according to the second embodiment, the arc shaped chamfered portions  35 ,  35  are formed by chamfering the corners of the front end portion MT 1 ′ in an arc shape. 
         [0082]    The arc shape chamfered portions  35 ,  35  and center part of the front end portion MT 1 ′ have each one third width of the full width of the tape MT. 
         [0083]    A cutter described in Japanese Laid-open Patent Application No. 02-158976 is utilized preferably, for forming the arc shape chamfered portions  35 ,  35 . 
         [0084]    The front end portion MT 1 ′ of the tape MT formed accordingly is adhered to the hub H by the tape-front-end-portion transport unit  22 . 
         [0085]    Accordingly, the following effect can be obtained in the tape cartridge  1 ′ according to the second embodiment. 
         [0086]    The turning up of the front end portion MT 1 ′ of the tape MT can be prevented effectively, since the corners of the tape MT are removed, thanks to the arc shape chamfered portions  35 ,  35  formed at the corners so that the chamfered portions and center portion of the front end portion MT 1 ′ of the tape MT have each one third width of the full width of the tape MT. 
         [0087]    The present invention is not limited to the above mentioned embodiments. 
         [0088]    For example, various changes are possible on the shape of the front end portions MT 1  and MT 1 ′ of the tape MT, if the turning up can be prevented. 
         [0089]    The present invention can be applied to any one of a magnetic tape cartridge, an optical record tape cartridge, etc., if the turning up of a front end portion of a tape can be prevented.