Abstract:
A method of aligning read elements and write elements with a storage media in a data storage device includes determining a position of a data track associated with the storage media, shifting one of a first and second head module relative to the storage media. The first head module includes at least one of a read element and a write element and the second head module includes at least one of a read element and a write element operatively associated with the at least one of the read element and write element of the first head module. The first head module is selectively shiftable relative to the second head module. The method further includes aligning one of the at least one read element and write element of the one of the first and second head module that is shifted with the data track on the storage media.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a divisional of U.S. application Ser. No. 12/391,379 filed Feb. 24, 2009, the disclosure of which is incorporated by reference herein in its entirety. 
     
    
     BACKGROUND 
       [0002]    The present invention relates to the art of dual actuators and, more specifically, to a dual actuator for a read-write data storage device. 
         [0003]    Modern magnetic tape based data storage devices simultaneously perform read and write operations in order to enhance system speed and reliability. Generally, the simultaneous read/write operation is achieved through the use of dual heads fixedly mounted to one another with each head having multiple readers and writers. More specifically, readers on one head are aligned with writers on another head so that data can be written and verified in a single operation. In this manner, system speed is enhanced while, at the same time, an overall error rate is reduced. That is, if too many read errors are detected, data is re-written without interruption in device operation. 
       SUMMARY 
       [0004]    According an exemplary embodiment of the invention, a method of aligning read elements and write elements with a storage media in a data storage device includes determining a position of a data track associated with the storage media, shifting one of a first and second head module relative to the storage media. The first head module includes at least one of a read element and a write element and the second head module includes at least one of a read element and a write element operatively associated with the at least one of the read element and write element of the first head module. The first head module is selectively shiftable relative to the second head module. The method further includes aligning one of the at least one read element and write element of the one of the first and second head module that is shifted with the data track on the storage media. 
         [0005]    Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention. For a better understanding of the invention with the advantages and the features, refer to the description and to the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0006]    The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The forgoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
           [0007]      FIG. 1  is a front perspective view of a data storage device constructed in accordance with exemplary embodiments of the invention; 
           [0008]      FIG. 2  is an upper left perspective view of a dual actuator constructed in accordance with exemplary embodiments of the invention; 
           [0009]      FIG. 3  is an exploded view of the dual actuator of  FIG. 2 ; 
           [0010]      FIG. 4  is an upper left perspective view of an actuator member assembly in accordance with exemplary embodiments of the invention; and 
           [0011]      FIG. 5  is an exploded view of a dual actuator constructed in accordance with exemplary embodiments of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0012]    With initial reference to  FIG. 1 , a data storage device constructed in accordance with exemplary embodiments of the invention is indicated generally at  2 . Data storage device  2  includes a main body  4  that houses various electronics (not shown). Data storage device  2  further includes a first storage media holder or reel  8  and a second storage media holder or reel  9 . First reel  8  is shown to include a storage media  14  that passes across a plurality of storage media guides  20 - 23  and is picked up on second reel  9 . Data is written to, and read from, storage media  14  by a head actuator assembly indicated generally at  34 . As will be discussed more fully below, head actuator assembly  34  must be properly aligned with storage media  14  in order to ensure proper reading, writing, and verifying of data. 
         [0013]    As best shown in  FIGS. 2-3 , head actuator assembly  34  includes a first head module  44  having a first end portion  46  that extends to a second end portion  47  through a data surface  49 . First head module  44  includes a plurality of read elements, one of which is indicated at  54 , as well as a plurality of write elements, one of which is indicated at  55 . Read elements  54  and write elements  55  are arranged in a staggered arrangement, i.e., one after the other along data surface  49 . Of course, other aspects of the invention could include read and write elements aligned with one another. First head module  44  also includes an actuator portion  59  that extends laterally outward away from data surface  49 . 
         [0014]    Head actuator assembly  34  also includes a second head module  62  that is movably mounted relative to first head module  44 . In a manner similar to that described above, second head module  62  includes a first end portion  64  that extends to a second end portion  65  through a data surface  67 . Second head module  62  includes a plurality of read elements, one of which is indicated at  70 , as well as a plurality of write elements, one of which is indicated at  71 . In the exemplary embodiment shown, read elements  70  and write elements  71  are arranged in a staggered configuration along data surface  67 . More specifically, read elements  70  are arranged opposite write elements  55  on first head module  44 , while write elements  71  are arranged adjacent to read elements  54 . With this arrangement, data is read and written or written and read, depending upon the operation, in order to verify data being read from or stored to storage media  14 . In a manner also similar to that described above, second head module  62  includes an actuator portion  80  that extends laterally outward away from data surface  67 . In order to ensure proper alignment between the plurality of read elements  54  on first head module  44  and write elements  51  on second head module  62 , as well as the write elements  55  and read elements  70 , each head module  44  and  62  is moveable relative to one another and head actuator assembly  34  in a manner that will be described more fully below. Towards that end, each head module  44  and  62  is mounted to an actuator member assembly  86  that is moveably mounted in head actuator assembly  34 . 
         [0015]    As shown, actuator member assembly  86  includes a main body  88  having a first end  89  that extends to a second end  90 . Actuator member assembly  86  further includes an actuator housing  91  ( FIG. 3 ) that supports a first-stage actuator assembly  94 . First-stage actuator assembly  94  includes a first-stage actuator element  99  that is selectively operated to move first and second head modules  44  and  62  relative to storage media  14 . First-stage actuator assembly  94  provides a first, or gross, adjustment of first and second head modules  44  and  62  relative to storage media  14  in order to properly align the plurality of read elements  54  and  70 , and write elements  55  and  71  with particular sectors on storage media  14 . 
         [0016]    In the exemplary embodiment shown, first-stage actuator element  99  takes the form of a coil that is selectively energized to move first and second head modules  44  and  62 . In order to actuate first-stage actuator element  99 , head actuator assembly  34  includes a first magnet support  106  positioned on a first side (not separately labeled) of actuator member assembly  86  and a second magnet support  107  positioned on an second, opposing side (not separately labeled) of actuator member assembly  86 . Magnet support  106  supports a pair of magnets  110  and  111  that are in operative communication with first-stage actuator element  99 . Likewise, second magnet support  107  supports a pair of magnets  112  and  113 , which are likewise in operative communication with first-stage actuator element  99 . In order to increase the force generated by the actuator, the assembly may also include a first magnet yoke  114  mounted on magnet pair  110  and  111 , and a second magnet yoke  115  mounted on magnet pair  112  and  113 . Once energized, first-stage actuator element  99  shifts actuator member assembly  86  that, in turn, shifts first and second head modules  44  and  62  relative to storage media. First-stage actuator element  99  has a range of motion of between about 1 mm and about 10 mm. In order to restrain the movement and restore actuator member assembly  86  to a home position, a first spring  120  is arranged at first end  89  and a second spring  121  is arranged at second end  90 . Of course it should be understood that other actuating elements, such as piezo-electric elements and the like could also be employed. 
         [0017]    In addition to the gross adjustment provided by first-stage actuator element  99 , head actuator assembly  34  includes a second-stage actuator assembly  128  that facilitates a fine or micro level of adjustment to provide additional, or a micro-tuning, adjustment to enhance alignment between read elements  54  with write elements  71  and write elements  55  with read elements  70 . Towards that end, second-stage actuator assembly  128  includes a first second-stage actuator element  131  that is operatively connected to first head module  44  and a second, second-stage actuator element  36  that is operatively connected to second head module  62 . More specifically, first second-stage actuator element  131  acts upon actuator portion  59  to move first head module  44  and second, second-stage actuator element  136  acts upon actuator portion  80  to move second head module  62 . In this manner, first and second second-stage actuator elements  131  and  136  are selectively activated to provide fine tuning adjustments between first head module  44  and second head module  62 . That is, second-stage actuator assembly  128  facilitates movement of first and second head modules  44  and  62  relative to one another. Towards that end, first and second second-stage actuator elements  131  and  136  have a range of motion of between about 10 microns and about 100 microns. In the exemplary embodiment shown, first and second second-stage actuator elements take the form of piezo elements however, it should be understood that other elements, such as voice coils could also be employed. 
         [0018]    Reference will now be made to  FIG. 4  in describing an actuator member assembly  146  constructed in accordance with another exemplary embodiment of the invention. As shown, actuator member assembly  146  includes a main body  148  having a first end  149  that extends to a second end  150 . Actuator member assembly  146  further includes an actuator housing  151  that supports a first-stage actuator assembly  154 . In a manner similar to that described above, first-stage actuator assembly  154  includes a first-stage actuator element  159  that, in the exemplary embodiment shown, takes the form of a voice coil. Actuator member assembly  146  further includes a second-stage actuator assembly  166  having a first second-stage actuator element  170  and a second, second-stage actuator element  172 . As will be discussed more fully below second, second-stage actuator element  172  is off-set from first second-stage actuator element  170  in order to negate any need to counterbalance movement within actuator member assembly  146 . 
         [0019]    In accordance with the exemplary embodiment shown, actuator member assembly  146  includes a first head module  180  having a first end portion  182  that extends to a second end portion  183  through a data surface  185 . In a manner similar to that described above, data surface  185  includes a plurality of read elements, one of which is indicated at  188  as well as a plurality of write elements, one of which is indicated at  189 . Read elements  188  and write elements  189  are arranged staggered, i.e., one after the other, along data surface  185 . It should be noted that pairs of read and write elements can also be arranged such that they are aligned with each other. First head module  180  also includes an actuator portion  191 . As shown, actuator portion  191  is arranged in a first orientation. More specifically, actuator portion  191  includes an actuator surface (not separately labeled) facing first end portion  182 . Actuator member assembly  146  further includes a second head module  194  having a first end portion  196  that extends to a second end portion  197  through a data surface  199 . Second head module  194  includes a plurality of read elements, one of which is indicated at  202 , as well as a plurality of write elements, one of which is indicated at  203 , arranged in a staggered relationship in a manner similar to that described above. In addition, head module  194  includes an actuator portion  206 . However, in contrast to the orientation of actuator element  191 , actuator portion  206  is arranged in a second orientation. More specifically, actuator portion  206  includes an actuator surface (not separately labeled) facing second end portion  197 . With this arrangement, forces applied by first second-stage actuator element  170  are balanced by forces applied by second, second-stage actuator element  172 . In this manner, balancing movement between first and second head modules  180  and  194  is not required and thus control schemes are simplified. 
         [0020]    Reference will now be made to  FIG. 5 , wherein like reference numbers represent corresponding parts and their respective views, in describing a head member assembly  224  constructed in accordance with yet another exemplary embodiment of the invention. As shown, head member assembly  224  includes a first actuator member assembly  226  and a second actuator member assembly  227 . First actuator member assembly  226  includes a first head module  230  and second actuator member assembly  227  includes a second head module  232 . With this arrangement, first actuator member assembly  226  is independently moveable relative to second actuator assembly  227  and, by extension, each head module  230  assembly is independently moveable relative to head module  232 . Towards that end, first actuator member assembly  226  includes a main body  236  having a first end  237  that extends to a second end  238  between which is positioned first head module  230 . In addition, first actuator member assembly  226  includes an actuator housing  240  that supports a first-stage actuator assembly  242  having a first, first-stage actuator element  244 . First actuator member assembly  226  is also shown to include a first, second-stage actuator element  247 . In a manner similar to that described above, first-stage actuator element  244  provides gross adjustments for first head module  230  while first, second-stage actuator element  247  provides fine adjustments. It will also be understood that operation is also possible using only the first stage of actuation. 
         [0021]    In a manner similar to that described above, second actuator member assembly  227  includes a main body  266  having a first end  267  that extends to a second end  268  between which is positioned second head module  232 . Second actuator member assembly  227  also includes an actuator housing  270  having a second, first-stage actuator assembly  272  provided with a second, first-stage actuator element  274 . Second actuator member  227  also includes a second, second-stage actuator element  277 . With this arrangement, second, first-stage actuator element  274  provides gross adjustment of second head module  232  while second, second-stage actuator element  277  provides fine tuning in order to ensure that read and write elements arranged on first head module  230  are properly aligned with corresponding read and write elements on head module  232 . Moreover, by mounting each head module  230  and  232  on a separate actuator member assembly  226 ,  227 , head member assembly  224  facilitates complete independent actuation in both the first and second-stages in order to provide proper alignment is facilitated. In a manner similar to that described above, in order to restrain the movement and restore each actuator member assembly  226 ,  227  to a home position, a first spring  280  is arranged at first ends  237  and  267  and a second spring  285  is arranged at second ends  238  and  268 . As shown, each spring  280 ,  285  is split in order to accommodate independent movement of each respective actuator member assembly  226 ,  227 . 
         [0022]    At this point it should be understood that exemplary embodiments of the invention provide a system for facilitating not only gross adjustment of head modules but, fine independent adjustment of associated head modules in order to enhance read/write accuracy and data integrity for a data storage device. In addition, data storage device  2  can be provided with a third head module  300  ( FIG. 1 ) provided with read and/or write elements (not separately labeled). Third head module  300  is associated with first and second head modules  44  and  62  and is selectively shiftable relative to first and/or second head modules  44  and  62  in order to still further enhance read/write accuracy and data integrity for a data storage device. 
         [0023]    The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof. 
         [0024]    The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of exemplary embodiments of the invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The exemplary embodiments were chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated 
         [0025]    While the preferred embodiment to the invention has been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described.