Abstract:
A disc holder having a rigid central core for projecting through the central aperture of an optical disc in order to hold the optical disc in place. The disc holder includes, in addition to the rigid central core, a base, several support arms that extend radially inwardly from the base to support the central core in spaced relation from the base, and securing means for releasably securing the rigid central core within the central aperture of the optical disc. The securing means includes locking fingers mounted on the central core. The locking fingers are biased outwardly against the edge of the central aperture of the disc when the disc is held by the disc holder. The locking fingers are moveable radially inward to fit within the central aperture of the disc, thereby allowing the disc to move over the locking fingers so that the disc can be put on or taken off the disc holder.

Description:
This application ia a continuation-in-part of U.S. Ser. No. 09/256,188, filed Feb. 24, 1999, now U.S. Pat. No. 6,085,900. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to optical disc storage and more particularly to an optical disc holder, as well as to disc containers incorporating such optical disc holders. 
     BACKGROUND OF THE INVENTION 
     The term “optical disc” in the context of this specification refers to laser-readable discs for carrying, for example, pre-recorded music, computer software, videos, films, interactive games, or other data. 
     Optical discs are conventionally stored in plastic cases when not in use. Such discs typically include a central aperture that is used to both play the disc and to hold the disc in place during storage. Conventional plastic storage cases include a disc-engaging member centrally disposed within the case that projects through the aperture of the disc and secures the disc in place within the case. Such disc-engaging member is typically formed by a plurality of inwardly extending arms that are fixed to the case at their outer ends. At their inner ends, the arms extend upwardly, away from the base portion of the case to which the outer ends of the arms are secured, to form the disc-engaging member that fits within the central aperture of the disc. 
     In many prior disc holders, such as the disc holder disclosed in U.S. Pat. No. 5,788,068, the disc-engaging member defined by the unstressed arms is too large to fit within the central aperture of the optical disc. To fit the disc-engaging member of such disc holders within the central aperture of the disc, the disc-engaging member is first forced downwardly towards the base. This downward motion of the disc-engaging member bends the plurality of arms, thereby moving the inner ends of the arms closer together and reducing the dimension of the disc-engaging member, which permits the disc-engaging member to fit within the central aperture of the disc. After the pressure is removed from the disc-engaging member, the arms return to their unstressed position, and the disc-engaging member increases in dimension to tightly grip the rim of the central aperture of the disc. In the disc holder disclosed in U.S. Pat. No. 5,788,068, as well as in other prior disc holders, the disc-engaging member has a lip defined by the arms curving slightly outwardly. After the pressure is released from the disc-engaging member of such a prior disc holder, the central aperture of the disc is secured on the disc-engaging member between the lip of the central aperture and the base. 
     Prior disc holders such as the disc holder disclosed in U.S. Pat. No. 5,788,068 may suffer from a number of disadvantages stemming from the uneven distribution of force to the arms that define the disc-engaging member. This uneven distribution of force can easily occur as a result of an uncentred downward pressure being applied to the disc-engaging member. This uneven distribution of forces to the arms may have a number of undesirable consequences for both the disc holder and the disc. Specifically, when force is unevenly applied to the arms, some arms may be pushed downwardly towards the base to a sufficient extent to permit the portion of the lip defined by such arms to disengage from the disc. However, other arms may not be forced down sufficiently to disengage the portion of the lip defined by such arms from the disc. The user may nonetheless attempt to remove the disc from the case, resulting in the disc being bent, which may damage the disc and result in loss of information carried on the disc. Alternatively, the user may press down harder but in much the same way in an attempt to release the disc, thereby increasing the wear on the arms of the disc holder. 
     The uneven application of force to the disc-engaging member may also result in the premature wearing out of the arms that define the disc-engaging member. These arms are particularly subject to wear as a result of being unsupported at one end. Once some of the arms are worn out, the disc holder is essentially worn out as the upwards resilience of the arms is required for the disc holder to continue to function effectively—it is the upward resilience of the arms that secures the disc in place. If force is unevenly distributed among the arms, then it is likely that some arms will wear out long before other arms or other components of the disc holder do. This problem is self-perpetuating, as arms that have previously been subjected to more force may be weaker and may bend more in response to the same force than other arms. Even a force that is evenly applied initially may become uneven as different arms bend to different extent; the force may then be increasingly allocated to the arms that bend more, resulting in still more wear to these arms. 
     Thus a disc holder that favors the even distribution of the force between different arms and mitigates the uneven wearing of arms is desirable. 
     SUMMARY OF THE INVENTION 
     An object of an aspect of the present invention is to provide an improved disc holder. 
     In accordance with an aspect of the present invention, there is provided an apparatus for releasably securing an optical disc having a central aperture. The apparatus includes a base, a rigid central core, a core support means for resiliently supporting the rigid central core in spaced relation from the base, and securing means for releasably securing the rigid central core within the central aperture of the optical disc. The rigid central core is dimensioned to fit within the central aperture of the optical disc and is spaced from the base. The core support means supports the rigid central core in spaced relation from the base such that the rigid central core is moveable towards the base when pressure is applied to the rigid central core, and the rigid central core is biased away from the base by the core support means after pressure is removed from the rigid central core. The securing means is disengaged when the rigid central core is forced towards the base to release the optical disc. 
     Preferably, the securing means comprises a plurality of locking fingers for engaging the disc at the central aperture thereof. The plurality of locking fingers are mounted on the rigid central core and are bendable radially inward to release the disc and radially outward to engage the disc. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A detailed description of preferred embodiments of the invention is provided herein below with reference to the following drawings, in which 
     FIG. 1 is a perspective view of a portion of a disc storage case that incorporates a disc holder in accordance with a preferred embodiment of the invention; 
     FIG. 2 in a side view illustrates the disc holder of FIG. 1 holding a disc; 
     FIG. 3 in a side view illustrates the disc holder of FIG. 1 in an intermediate position between holding and releasing the disc; 
     FIG. 4 in a side view illustrates the disc holder of FIG. 1 when the disc is released; 
     FIG. 5 is a perspective view of the disc holder of FIG. 1 shown isolated from the disc storage case; 
     FIG. 6 is a partial side view of a disc holder in accordance with a further preferred embodiment of the invention together with a disc released by the disc holder; 
     FIG. 7 in a partial side view illustrates the disc holder of FIG. 6 holding a disc; 
     FIG. 8 is a perspective view of a portion of a disc storage case that incorporates a disc holder in accordance with a further preferred embodiment of the invention; 
     FIG. 9 in a sectional view along line  2 — 2  of FIG. 8 illustrates the disc holder of FIG. 8 when the disc is released; 
     FIG. 10 in a sectional view along line  2 — 2  of FIG. 8 illustrates the disc holder of FIG. 8 holding a disc; and, 
     FIG. 11 in a sectional view along line  2 — 2  of FIG. 8 illustrates the disc holder of FIG. 8 in an intermediate position between holding and releasing the disc. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1 there is illustrated a part of a disc storage case incorporating a disc holder  18  in accordance with a preferred embodiment of the invention. FIG. 5 in a perspective view, shows the disc holder  18  of FIG. 1 isolated from one disc case  40 . A disc storage case typically comprises a lid and a base portion, both made of a clear plastic. An edge of the lid is hinged to an adjoining edge of the base portion, but the other edges of the base portion and the lid can be readily separated in order to open the case. The lid has a disc-receiving recess that adjoins a matching disc-receiving recess in the base portion when the case is closed. 
     The disc holder  18  is centrally disposed in the matching disc-receiving recess of the base portion of the disc storage case, and includes a base  20  that is integral with the base portion of the disc storage case. Support arms  22  extend upward and inwardly from the base  20  to a one-piece central core  26 . All of the support arms  22  are attached to and support the central core  26  at its periphery. Between the juncture of each of the support arms  22  with the central core  26 , are locking fingers  28  that extend substantially upwardly from the central core  26 . Each of the locking fingers  28  is accommodated within a unique one of a plurality of vertical slots  29  in the central core  26 . Each of the locking fingers  28  terminates in an outwardly extending hook  30 . 
     Central core  26  is rigid and has a raised portion to which pressure may be applied. When pressure is applied to the central core  26  at the raised point, the resulting force is evenly distributed among the support arms  22 , which flex and bend at the central core  26  to permit the central core  26  to move towards the base  20 . The support arms  22  diverge from the base at an angle of inclination  34 . Even when no pressure is applied to the core  26  and the support arms  22  are unstressed, the angle of inclination  34  is very small as the inward directional component of the support arms  22  is much greater than their upward directional component. When the support arms  22  are stressed, the angle of inclination  34  changes by only a few degrees, and there is comparatively little bending at the core  26 . The resistance of the support arms  22  to further bending varies directly with the extent to which the support arms  22  have already been bent, which aids in distributing forces applied to the core  28  equally among the support arms  22 . 
     In FIGS. 2,  3  and  4 , the disc holder  18  of FIG. 1 is shown with a disc  42 . In FIG. 2, the disc holder  18  is shown holding the disc  42  in place. In FIG. 4, the disc holder  18  is shown with the disc  42  released, while in FIG. 3 the disc holder  18  is shown with the disc  42  in an intermediate position between being held and being released. Initially, a disc  42  can be received by the disc holder  18  by first placing the disc  42  in the position shown in FIG.  4 . In this position, disc  42  is supported above the central core  26  by the fingers  28  and hooks  30 . Pressure is then applied to the disc  42  to push the disc  42  down onto the hooks  30 . The hooks  30  have a semi-circular contour that redirects the downward pressure on the disc  42  as a radially inward pressure on the locking fingers  28 , which moves the locking fingers  28  radially inward into the slots  29  and out of the way of the disc  42 . As a result of the locking fingers  28  moving inwardly into the slots  29 , the hooks  30  no longer support the disc  42  and the disc  42  slides down, receiving the central core  26  through the central aperture. The disc  42  is then supported by support pegs  24 . After the disc  42  is in place about the central core  26 , and the pressure is removed, the resilience of the locking fingers  28  moves them outwardly out of their inward orientation and the hooks  32  engage with the face of the disc  42  that is opposite to the face that is supported by the support pegs  24 . The disc is then supported against movement perpendicular to the plane of the disc  42  by the hooks  32  and the support pegs  24 . The central core  26  extending through the central aperture restrains the disc  42  from movement parallel to the plane of the disc  42 . 
     Central core  26  is rigid and has a raised portion to which pressure may be applied. When pressure is applied to the central core, the locking fingers  28  are pressed downwardly, and the hooks  30  are pushed against the disc  42 . Due to the semi-circular contour of the hooks  30 , the force exerted on hooks  30  by the disc  42  is redirected radially inward to push the locking fingers  28  into the slots  29  and out of the way of the disc  42  so that the disc  42  can be taken off of the central core  26 . 
     Referring to FIG. 6, there is illustrated in a side view, a disc holder  118  in accordance with a further preferred embodiment of the invention. The disc holder  118  is shown with a disc  142  that is on top of, but is not held by, the disc holder  118 . Similar to the preferred embodiment of the invention shown in FIGS. 1 through 5, support arms  122  extend upwardly and inwardly from a base  120  to a central core  126 . All of the support arms  122  are attached to the central core  126 . Between the juncture of each of the support arms  122  with the central core  126 , are locking fingers  128  that extend substantially upwardly from the central core  126 . Each of the locking fingers  128  terminates in an outwardly extending hook  130 . The disc  142  is impeded from sliding down around the central core  126  by the locking fingers  128  and the hooks  130 , which initially do not fit through the central aperture of the disc  142 . 
     When pressure is applied to the disc  142 , the resulting force is distributed between the hooks  130 . Due to the semi-circular contour of the hooks  130 , this force is redirected radially inward to push the locking fingers  128  into the slots  129  and out of the way of the disc  142  so that the disc  142  can slide down around the central core  126 . The disc  42  is then supported by support pegs  124  that are themselves supported by peg support arms  125 . The peg support arms  125  extend upwardly from the base  120  and also resilient. When the pressure is taken off, the fingers  129  resume their relaxed orientation in which the hooks  30  press against the face of the disc  142  that is opposite to the face supported by the support pegs  124 . FIG. 7 shows, in a side view, the disc holder  118  holding a disc  142 . This disc is resiliently retained on one side by the support pegs  124  mounted on resilient peg support arms  125 , and on the other side by the hooks  130 . 
     Central core  126  is rigid and has a raised portion to which pressure may be applied. When pressure is applied to the central core, the locking fingers  128  are pressed downwardly, and the hooks  130  are pushed against the disc  142 . Due to the semi-circular contour of the hooks  130 , the force exerted on hooks  130  by the disc  142  is redirected radially inward to push the locking fingers  128  into the slots  129  and out of the way of the disc  142  so that the disc  142  can slide off of the central core  126 . 
     Referring to FIG. 8, there is illustrated a part of a disc storage case incorporating a disc holder  218  in accordance with a further preferred embodiment of the invention. As with the previously described embodiments, the disc holder  218  is centrally disposed in a disc-receiving disc recess of the disc storage case, and includes a base  220  that is integral with the base portion of the disc storage case. Support arms  222  extend upwardly and inwardly from the base to a central core  226 . All of the support arms  222  are attached to and support the central core  226  at is periphery. Between the juncture of each of the support arms  222  with the central core  226  are linking fingers  228  that extend substantially downwardly from the central core  226 . Each of the locking fingers  228  includes a protrusion  234  that extends radially outwardly from the locking finger  228 . 
     Central core  226  is rigid. When pressure is applied to this central core  226 , the resulting force is evenly distributed among the support arms  222 , which flex and bend about the central core  226  to permit the central core  226  to move towards the base  220 . The support arms  222  diverge from the base at a slight angle of inclination. 
     In FIGS. 9,  10  and  11  the disc holder  218  of FIG. 8 is shown with a disc  242 . In FIG. 9, the disc holder  218  is shown with the disc  242  released, while in FIG. 10, the disc holder  218  is shown holding the disc  242  in place. In FIG. 11, the disc holder  218  is shown with the disc  242  in an intermediate position between being held and being released. 
     The disc  242  can be received by the disc holder  218  by first placing the disc  242  in the position shown in FIG.  9 . In this position, the disc  242  is supported near the top of the central core  226 . At its upper surface, the central core  226  is integral with the locking fingers  228 . Specifically, each locking finger  228  includes a free end  232 , and a fixed end  230 . The fixed end  230  is attached to and integral with the central core  226 . Each locking finger  228  extends downwardly towards the base from its fixed end  230  to its free end  232 . Each locking finger  228  also includes a protrusion  234  that projects radially outwardly away from the central core  226 . The protrusion  234  itself includes a leading edge  238  and a ridge  234 . The leading edge  238  begins substantially at the fixed end  230  of each locking finger, and tapers gradually radially outwardly towards the ridge  236 . 
     When the disc  242  is initially placed on the disc holder  218 , the disc  242  is supported above the ridge  236  by the leading edge  238  of the protrusion  234 . When a downward pressure is applied to the disc  242 , this downward pressure is transferred to the leading edge  238  at each locking finger  226 . The leading edge  238  redirects some of this downward pressure into inward pressure. This, in turn, effects inward bending of the locking finger  228  as shown in FIG. 11, thereby permitting the disc  242  to slip down over the ridge  236 . Once the disc  242  is below the ridge  236 , and the downward pressure on the disc  242  is released, the natural resilience of the locking fingers  228  will return them to their original position, except that now the ridge  236  is above the disc  242  as shown in FIG.  10 . The ridge  236  then holds the disc  242  in place. 
     Bending of the locking finger  228  is facilitated by a notch or live hinge  240  out into the central core  226  adjacent to the fixed end  230  of the locking finger  228 . When installed in the position shown in FIG. 10, the disc  242  is supported against movement perpendicular to the plane of the disc  242  by the ridge  236  and support pegs  224 . The central core  226  extending through the central aperture of the disc restrains the disc  242  from movement parallel to the plane of the disc  242 . 
     Central core  226  is rigid. When pressure is applied to the central core  226 , the support arms  222  give slightly and the locking fingers  228  move slightly downwardly. Each locking finger has a lower edge  239  that is pressed against the disc  242  as a result of the downward movement of the locking finger. The lower edge  239  is tapered radially inwardly so as to direct the upward reactive force of the disc  242  against the lower edge  239  radially inward. The radially inward component of the reactive force exerted on the lower edges  239  by the disc  242  bends the locking fingers  228  about the live hinges  240 . Once the locking fingers  226  have bent sufficiently radially inward to permit the ridge  236  to fit within a central aperture of the disc  242 , the ridge  234 , as is shown in FIG. 11, can be pushed below the disc  242 . Then, when pressure on the central core  226  is released, the natural resilience of the locking fingers  228  will cause the locking fingers  228  to once again bend outwardly, such that the ridge  236  will no longer fit within the central aperture of the disc  242  and the disc  242  will be supported by the leading edge  238  of the protrusion  234  as shown in FIG.  9 . 
     According to the preferred embodiment, the leading edge  238  for each locking finger  228  is uniformly tapered. This facilitates proper engagement of the disc  242  with the core  226  during insertion in that the disc  242  is evenly guided down around the central core  226 . This is particularly important in relation to high speed automatic disc insertion machines. Further, it is important that the lower edge  239  of each locking finger  226  be uniformly tapered to permit even disengagement of the ridge  236  from the disc  242  to facilitate removal of the disc  242 . 
     By varying the depth of the cut of the live hinge  240 , the flexibility of the live hinge  240  can be accurately varied over a moderately large range without jeopardizing the overall structural rigidity of the central core  226 . Different live hinge depths will be appropriate for different plastics having different resistence to bending and natural resilience. 
     Other variations and modifications are possible. All such modifications or variations are believed to be within the scope of the invention as defined by the claims appended hereto.