CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/508,378, filed Jul. 15, 2011, which is hereby incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to the field of in-vehicle entertainment. More particularly, the invention relates to a device that mounts a tablet computer onto the support posts of a vehicle headrest. 
       SUMMARY 
       [0003]    One embodiment of the present invention utilizes a two-piece mount to attach a tablet computer to a vehicle headrest. The first piece constitutes a tablet housing, having a rigid core attached to a flexible outer rim portion. The flexible rim portion is sized so that it can stretch around the circumference of the tablet computer and hold the tablet securely within the tablet housing. The tablet housing is open in the front to allow full access to the front of the tablet, and smooth and thin at the back to allow the tablet computer to be comfortably used by a user while the tablet remains within the tablet housing. In effect, the tablet housing acts as a protective case for the tablet computer. 
         [0004]    The tablet housing has a rigid core portion with a circular cavity in the rear. In the circumference of the circular cavity is a circular groove or channel. The tablet housing can be attached to the headrest coupling portion of the mount through this circular groove. The headrest coupling contains a circular attachment disk that fits within the circular cavity. On the edge of the attachment disk is at least one retractable tab that extends away from the attachment disk. This tab can be retracted to allow the attachment disk of the headrest coupling to be inserted into the circular cavity of the tablet housing. The tab can be extended into the groove within the circumference of the circular cavity. The tab interacts with the groove to prevent the tablet housing from falling off of the attachment disk of the headrest coupling. In one embodiment, the tablet housing can rotate with respect to the headrest coupling, with the tab of the attachment disk rotating within the groove of the circular cavity. Stops within the groove of the circular cavity can limit the rotation of the tablet housing. In the preferred embodiment, the tab allows the tablet housing to rotate ninety degrees from a horizontal position to a vertical position. 
         [0005]    The headrest coupling uses two hinged arms to lock the headrest coupling to the post of the headrest in the vehicle. A toothed gripping surface on the interior of the hinged arms and the exterior of the base of the headrest coupling help prevent the headrest post from slipping, while a locking clip tightly holds the hinged arms in place. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a perspective view of one embodiment of a headrest mount for a tablet computer. 
           [0007]      FIG. 2  is an exploded, perspective view the headrest mount of  FIG. 1 . 
           [0008]      FIG. 3  is a perspective view of a tablet housing containing a tablet computer. 
           [0009]      FIG. 4  is a perspective view of a headrest coupling being attached to the headrest poles of a vehicle headrest. 
           [0010]      FIG. 5  is a perspective view of a left attachment mechanism of a headrest coupling. 
           [0011]      FIG. 6  is a view of the attachment mechanism of  FIG. 5 , with a closed locking clip. 
           [0012]      FIG. 7  is an exploded view of the headrest mount of  FIG. 3 , showing the rear of the tablet housing. 
           [0013]      FIG. 8  is an exploded, top plan view of a headrest mount. 
           [0014]      FIG. 9  is the top plan view of the headrest mount with the tablet housing attached to the headrest coupling. 
           [0015]      FIG. 10  is a front plan view of a headrest mount showing the rotational position of a tablet housing in phantom. 
           [0016]      FIG. 11  is a right plan view of a headrest mount showing the tilted positions of the tablet housing in phantom. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0017]      FIG. 1  shows one embodiment of a headrest mount  10  for a tablet computer. The mount  10  consists of two separable elements. The first element is the headrest coupling  100 , which attaches the mount  10  to the headrest support poles (not shown). The second element is the tablet housing  200 , which serves to hold and protect the tablet computer (also not shown). The headrest coupling  100  utilizes two hinged arms  110 , each of which rotates about a hinge mounted in the main body  120  of the headrest coupling  100 . Inside each hinged arm  110  is a toothed gripping surface  112  formed of a rubber or rubber-like synthetic compound. The surface  112  has individual ridges or teeth to help hold the headrest support posts when the headrest mount  10  is positioned within a vehicle. The toothed gripping surface  112  is also found on the corresponding exterior surface of the main body  120 , as shown in  FIG. 1 , so as to surround the headrest post with the surface  112  on two sides. The hinged arms  110  are held closed by clip  130  located on the two ends of the elongated main body  120 . 
         [0018]    The main body  120  of the headrest coupling  100  will preferably also have constructed into it a power plug holder  122 . In the disclosed embodiment, this holder  122  is a recess in the main body  120 . Inside this recess is a plug made out of an elastic rubber or rubber-like synthetic compound, with this plug itself containing an interior recess  124 . The interior recess  124  in the plug holder  122  is sized and shaped to receive a portion of a charging cable used to charge the tablet computer that is mounted into the headrest mount  10 . In the embodiment shown in  FIG. 1 , the interior recess has an elongated, narrow cross-section, designed to receive a plug that is itself inserted into the tablet computer. 
         [0019]    The tablet housing  200  is itself constructed of two primary components, namely a rigid core  210  and a flexible rim or exterior  220 . In the preferred embodiment, the rigid core  210  is formed out of a rigid plastic and has flanges  212  to help secure the core  210  to the rim  220 . The flexible rim  220  is formed from a rubber or rubber-like synthetic compound that allows the rim  220  to be slightly stretched and then return to its original shape. The rim  220  preferably contains a plurality of apertures or tablet control access ports  222  near the outer periphery of the rim  220 . These ports  222  are sized and located to allow access to control buttons and interfaces of the tablet computer when the tablet is inserted into the tablet housing  200 . 
         [0020]      FIG. 2  shows the headrest mount  10  with the headrest coupling  100  separated from the tablet housing  200 . In this figure, headrest coupling  100  is attached to posts  320  that extend between a vehicle seat  300  and the seat&#39;s headrest  310 . The hinged arms  110  of the headrest coupling  100  each wrap around one of the posts  320 , trapping the posts  320  between the toothed gripping surface  112  of the arms  110  and the toothed gripping surface  112  found on the body  120  of the headrest coupling  100 . The locking clips  130  are in the closed position, preventing the hinged arms  110  from moving and compressing the arms  110  against the posts  320 . 
         [0021]    The headrest coupling  100  attaches to the tablet housing  200  via an attachment disk  140  that extends from the main body  120  of the coupling  100 . In one embodiment, the attachment disk  140  connects to the body  120  via a hinge  150 , which allows the attachment disk  140  to tilt up and down. Two retractable tabs  142  extend from the edges of the attachment disk  140 , to help hold the attachment disk to the rigid core  210  of the tablet housing  200 , as is described in more detail below in connection with  FIG. 7 . The retraction buttons  144  (only one shown in  FIG. 2 ) that are located proximal to the retractable tabs  142  operate to retract the tabs  142  whenever the buttons  144  are pressed inward. Springs within the headrest coupling  100  re-extend the tabs  142  and the buttons  144  when pressure is removed from the buttons  144 . 
         [0022]    The tablet housing  200  is shown with a tablet computer  250  held in place by the flexible rim  220  of the tablet housing  200 . The tablet computer  250  can be any relatively flat device with a display screen that can be used in a vehicle to present entertainment programming, play games, or run applications. Examples of existing tablet computers  230  include the Apple iPad devices (from Apple Inc. of Cupertino, Calif.) and tablet computers running the Android operating system from Google Inc. (Mountain View, Calif.). The tablet  250  is inserted into the tablet housing  200  by stretching the flexible rim  220  around the circumference  252  of the tablet  250 , as shown in  FIG. 3 . During normal insertion, one side of the tablet  250  is first positioned within the flexible rim  220  so an inward facing ridge  224  on the rim  220  extends slightly over the front face  254  of the circumference  252  of the tablet computer  250 . The final corner  226  of the flexible rim  220  is then stretched around the last corner of the tablet  250 , ensuring that the tablet is securely held by the tablet housing  200 . The rubber or rubber-like consistency of the flexible rim  220  helps protect the tablet computer  250  in case of accidental drops, even if the tablet  250  were to fall flat on its face  254 . In addition, the flexible rim  220  provides a comfortable grip for users when the combination tablet  250  and tablet housing  200  are used in hand-held mode separated from the headrest coupling  100 . 
         [0023]    In other embodiments, the flexible rim  220  is replaced by any known technique for securing a tablet computer  250 , such as straps, elastic bands, moveable bars, and the like. In these embodiments, the headrest coupling  100  may still attach to the tablet housing  200  through the rigid core  210 . It is not necessary that the tablet computer  250  be secured by stretching the elastic rim  220  around the computer as long as some attachment mechanism is used by the tablet housing  200  to secure the tablet  250 . 
         [0024]      FIG. 4  shows the process that is used to attach the headrest coupling  100  to the posts  320  of the vehicle headrest  310 . The locking clips  130  are released, allowing the hinged arms  110  to open. The arms  110  open wide enough to allow the arms to pass between the two headrest poles  320  while the headrest coupling  100  is moved forward below the headrest  310 , as indicated by the arrow  400  in  FIG. 4 . Once the body  120  of the headrest coupling  100  is adjacent the poles  320 , the hinged arms  110  are closed around the poles  320  as indicated by arrows  402 . When the arms  110  are closed, the locking clips  130  are used to secure the arms  110  in a closed position. Each locking clip  130  has a projection  132  that is received in an indentation (not shown) on the hinged arm  110 . This prevents that portion of the clip  130  from moving with respect to the hinged arm  110  during the locking action. On the opposite end of the clip  130  from the projection  130  is the base portion  134  of the locking clip. The base portion  134  is sized and positioned to be received by an engaging depression  126  in the base  120  of the headrest coupling  100 . As shown in  FIG. 5 , the hinged arm  110  is held closed by the projection  132  of the clip, while the based is pulled over (arrow  500 ) to be received by the engaging depression  126 . The closed clip  130  is shown in  FIG. 6 . Preferably, the natural opening between the toothed gripping surface  112  on the hinged arm  110  and the toothed gripping surface  112  on the base  120  of the headrest coupling  100  is sized to be smaller than most or all anticipated headrest posts  320 . In this way, the gripping surfaces  112  will be compressed against the post  320 , preventing the post  320  from moving relative to the headrest coupling  100  when the clip  130  is closed. The clip  130  can be unlocked by simply pushing the base portion  134  away from the body  120  of the headrest coupling  100 . 
         [0025]    The mechanism for attaching the headrest coupling  100  to the tablet housing  200  is shown in  FIG. 7 . As described above, the headrest coupling  100  has a rigid core  210  preferably constructed of hard plastic. The front portion of this core  210  shown in  FIG. 1  includes a plurality of flanges  212  that help secure the rigid core  210  to the flexible rim  220 . The rear portion of the core  210  has a circular wall  230  as shown in  FIG. 7 . This circular wall  230  surrounds a circular cavity  232 . The back surface  234  of the cavity  232  is still part of the rigid core  210 . Along the circular circumference of cavity  232  is a circular track  236 , which is essentially a thin, uniform indentation or channel in the wall  230  of cavity  232 . The track  236  is located approximately halfway into the cavity  232 . 
         [0026]    The attachment disk  140  of the headrest coupling  100  also has a circular shape, and is designed to be received within the circular cavity  232  of the rigid core  210  of the tablet housing  200 . When the retraction buttons  144  are pushed, the tabs  142  of the attachment disk  140  are retracted, and the attachment disk  140  may then be inserted into the cavity  232 . This is shown in  FIG. 8 , where pressing of the buttons  144  (arrow  800 ) causes retraction of the tabs (arrow  802 ), thereby allowing the attachment disk  140  to be inserted into the cavity  232  of the tablet housing  200  (arrow  804 ). 
         [0027]    When the retraction buttons  144  are released, the retractable tabs  142  re-extend into the track  236  of the circular wall  230 . The engagement between the tabs  142  and this track  236  prevents the headrest coupling  100  from being removed from the tablet housing  200  until the retraction buttons  144  are pressed again. This engagement is shown in  FIG. 9 , where the attachment disk  140  has been successfully inserted into the cavity  232 , with the retractable tabs  142  extended into the circular channel  236 . 
         [0028]    In the preferred embodiment, the track  236  extends along the wall  230  more than is necessary to receive the length of the retractable tabs  142 . This allows the tablet housing  200  to be rotated with respect to the headrest coupling  100 , with the tabs  142  sliding within the tracks  236  without danger of the tabs  142  falling out of the tracks  236  and decoupling the attachment disk  140  from the tablet housing  200 . To assist in this rotation, the tabs  142  have an arcuate shape that is shaped to match the inner diameter of the track  236 . In the preferred embodiment, the track  236  does not extend through the whole circumference of the circular wall  230  uninterrupted. This means that the tablet housing  200  may not rotate completely when attached to the attachment disk  140  of the headrest coupling  100 . Instead, stops within the tracks  236  (or the end of the track  236  itself) limits this rotation to ninety degrees. By careful placement of the stops or ends of the track, the rotation is preferably bounded by positions where the rectangular tablet housing  200  is presented in horizontal and vertical positions relative to the elongated body  120  of the headrest coupling  100 . Careful manufacture of the track  236  also allows a frictional engagement at these two positions, thereby preventing drift or accidental movement away from the horizontal or vertical positions while still allowing rotation when desired by the user. This is shown in  FIG. 10 , wherein the tablet housing  200  is shown in a vertical position with respect to the headrest coupling  100 , and arrows show how the tablet housing  200  can be rotated into a horizontal position (shown in phantom). 
         [0029]    In one embodiment, the attachment disk  140  is connected to the body  120  of the headrest coupling  100  through a hinge  150 . As shown in  FIG. 11 , the hinge  150  allows the tablet housing  200  and the tablet computer  250  to tilt upward and downward when the tablet housing  200  is mounted to the headrest coupling  100 . 
         [0030]    One advantage of attaching the headrest coupling  100  to the tablet housing  200  through the attachment disk  140  and circular cavity  232  is the ease with which the two components  100 ,  200  can be separated. Even after mounting in a vehicle, a user can simply press the retraction buttons  144  and pull the tablet computer  250  and tablet housing  200  off of the headrest coupling  100 . Since the tablet housing  200  takes the form of a protective cover for the tablet computer  250 , the tablet  250  can comfortably be used in the user&#39;s hands or lap without removing the tablet  250  from the tablet housing  200 . Temporary handheld use is therefore possible. When the tablet  250  needs to be remounted, the retraction buttons  144  are pressed, and the tablet housing  200  is reattached to the attachment disk  140 . 
         [0031]    The many features and advantages of the invention are apparent from the above description. Numerous modifications and variations will readily occur to those skilled in the art. Since such modifications are possible, the invention is not to be limited to the exact construction and operation illustrated and described. Rather, the present invention should be limited only by the following claims.
A device and method is presented that attaches a tablet computer to a vehicle headrest. A two-piece mount has a headrest coupling and a tablet housing. The tablet housing has a rigid core attached to a flexible rim portion that secures the tablet computer within the tablet housing. The rigid core has a circular cavity in the rear. The headrest coupling mounts to headrest posts in a vehicle using hinged arms and locking clips. The headrest coupling further has a circular attachment disk that fits within the circular cavity of the tablet housing. Retractable tabs in the circumference of the attachment disk fit within tracks in the walls of the circular cavity. The tabs prevent accidental separation of the tablet housing from the headrest coupling, and allow rotation of the tablet housing when attached to the headrest coupling.