Abstract:
A case for a portable electronic device such as cell phones, cameras, MP3 players and PDAs wherein said case includes material at the corners to provide protection to the electronic device. To reduce bulk at the corners and allow the material forming the case to conform with the contours of the device, the protection at the corners includes strips of material defining apertures there between. The apertures provide reduction in bulk and allow the case to conform to the corners of the device therein. Alternately, the protection at the corners can be provided by other structures co-molded into the corners of the cases. Such structures include material that is of a reduced thickness than other material used in the case, or structures that are formed to conform to the corners of the case. Such structures can be joined to the material forming the panels of the case by co-molding.

Description:
RELATED APPLICATION 
     This application claims priority to U.S. Provisional Application No. 60/756,157 filed on Jan. 4, 2006. The Application is also a continuation in part of U.S. Non-provisional application Ser. No. 11/275,443 filed on Jan. 3, 2006, which claims the benefit of U.S. Provisional Application No. 60/641,204, filed Jan. 3, 2005, the contents of which are incorporated herein by reference in their entirety. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to carrying cases for portable electronic devices, such as cell phones, cameras, MP3 players, and PDAs. More particularly, the invention relates to cases having corner protectors. Further, the invention relates to a case for a clamshell type cellular phone. The invention also relates to methods for producing the case using a co-molding process. 
     BACKGROUND OF THE INVENTION 
     Cell phones, pagers, PDA&#39;s, MP3 players, and other portable electronic devices have become increasingly popular. Users of the devices like to keep the devices readily accessible on their person. Due to their portable nature, the devices are also subject to being dropped and otherwise roughly handled, which can result in damage to the electronics inside, or to the plastic housing of the device. To address the above concerns, cases have been developed to both carry and protect the portable electronic devices. These cases often include a clip or other retaining structure to allow the case to be removably attached to the user&#39;s clothing, such as a belt. 
     The clips or retainers commonly used are removeably attached to the case by fastening to a plastic post, which itself is attached to the case. The plastic post can be an integral part of the case, being formed of the same material as the case. In other prior art embodiments, the post is a separate piece, sewn into or otherwise permanently attached to the case. While this provides a secure attachment post for the clip, the post becomes a cumbersome and unwanted protrusion when the clip is removed. The case disclosed herein is provided with a detachable post, thereby providing a case unburdened with unnecessary protrusions. The case disclosed herein also provides an attachment point for other accessories such as a light, velcro, keychain or magnets. 
     The portable electronic cases of the prior art are generally constructed of leather, nylon, or other material provided in sheets. The material is cut to predetermine sizes to form panels, which are then sewn or otherwise attached to form a pocket for holding the portable electronic device. With this type of construction, if one desires parts of a panel to have different physical properties, such as elasticity, texture, color or clarity, different pieces of material must be physically joined to one another to create a panel having the desired characteristics. Typically, the materials are joined by stitching, heat weld, or adhesive. The seams created at the joints add unwanted bulk and add to the cost of construction. It is therefore desirable to produce a case that includes different physical properties, but does not require pieces to be mechanically joined. To that end, the case disclosed herein is constructed of a co-molded material. 
     For cases designed for clamshell devices, such as cellular phones, the prior art teaches cases having two detachable pocket sections. Each pocket section fits over a section of the clamshell phone and are then connected by a snap, zipper, or velcro. Because of the nature of the case materials, if the pocket sections were not detachable, there would be no way to place the case on the phone, as leather and nylon do not stretch sufficiently to allow one pocket to be placed on the phone and then have the other pocket placed on the phone. By use of the co-molded material described herein, sufficient elasticity may be incorporated into the case to allow the case to be constructed as a single unit. In other words, the two pockets do not have to be separable. Further, the elasticity of the material allows the case to give and fit the contours of the phone in a superior fashions when compared to the prior art. 
     SUMMARY OF THE INVENTION 
     The invention disclosed herein is an improvement for cases typically used with cell phones and portable electronic devices. Some of the cases described include cut out areas or apertures or areas without material at corners of the device. The apertures allow for reduced thickness and bulk where the case would normally cover the corners of the device. This aperture or open area allows the cell phone case to be constructed without the need to notch or dart the case material to allow the material to fit the curve of the corner of the cell phone or other portable device. 
     However, the resulting apertures are not without their problems. The apertures leave the corners of the cell phone exposed and unprotected. If the cell phone or other portable electronic device is dropped, the exposed corner of the device may be subject to impact with the ground, possibly resulting in damage of breakage of the device. Thus, it is object of the invention to provide protection to the cell phone or electronic device, while still providing a construction that eliminates or reduces the issues associated with sowing or otherwise bonding materials to fit a curved surface. 
     The disclosure describes an improved portable electronics case and a method of constructing the same. The cell phone case is formed of a co-molded material produced by pouring a first liquid plastic into a mold, and then pouring a second liquid plastic into the mold, the second plastic having physical characteristics different from the first. Once set, the material is removed from the mold and sewn to form pockets for the electronic device. 
     If the case is to be used for a clamshell type cellular phone, two pockets are formed, the pockets sharing a common or continuous panel Further, the disclosure describes a unitary case for clamshell phones, allowing for both donning and removal of the case onto the phone as a unit. 
     Further, the disclosure describes a case including a removable post or attachment point for a clip. The retainer used to hold the removable post, may be used to house other devices, such as a light, keychain, velcro, magnets, or other useful items. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective of a case for a clamshell phone, the case having a removable post. 
         FIG. 2  is a perspective view of a case for a clamshell phone, showing a clip. 
         FIG. 3  is a perspective view showing a clip and post interface. 
         FIG. 4  is a cutaway drawing showing removal of the post from the retainer. 
         FIG. 5  is a sectional view of  FIG. 4 . 
         FIG. 6  is a perspective view showing the donning of the case onto a clamshell phone. 
         FIG. 7  is a perspective view showing the insertion of the phone into the second pocket. 
         FIG. 8  is a perspective view showing the case on a clamshell phone. 
         FIG. 9  is a perspective view showing the case on a closed clamshell phone 
         FIG. 10  is a top view of a mold for a case panel having a first texture portion, piping, and two non-texture portions. 
         FIG. 10a  is a cross sectional view of the mold. 
         FIG. 10b  is a second cross sectional view of the mold. 
         FIG. 11  is a cross sectional view of the mold showing a first substance or layer in the non-textured area of the mold. 
         FIG. 12  is a cross-sectional view of the mold showing a second substance located in the textured area of the mold. 
         FIG. 13  is a cross-sectional of the mold showing third substance poured over the previous two substances. 
         FIG. 14  is a cross-sectional view of the mold, including areas of piping, and showing a first substance poured into the piping. 
         FIG. 15  is a cross-sectional view of the mold showing a second material layered over the piping in the first non-textured area of the mold. 
         FIG. 16  shows a third substance layered over the previous two substances and overlaying the entire panel area of the mold. 
         FIG. 17  is a cross-sectional view of the mold showing a first substance poured into the non-textured area of the mold showing a scrim located on top of the first substance. 
         FIG. 18  is a cross-sectional view of the mold showing a reinforcement member placed into the mold about the perimeter. 
         FIG. 19  is a cross sectional view of an empty mold. 
         FIG. 20  is a perspective view of an alternate embodiment of a base. 
         FIG. 21  is a perspective view of an alternate embodiment retainer and base with a rectangular aperture. 
         FIG. 22  shows a post including a lug with a non-circular portion. 
         FIG. 23  is a side view of a post and retainer in a secured relationship. 
         FIG. 24  is an alternate base without a post. 
         FIG. 25  is a perspective view of a bayonet mount post and retainer. 
         FIG. 26  is a bottom perspective view of a bayonet mount post and retainer. 
         FIG. 27  is a front view of a cell phone in a cell phone case including corner protection. 
         FIG. 28  is a side view of a cell phone in a cell phone case including corner protection. 
         FIG. 29  is a rear view of a cell phone in a cell phone case including corner protection. 
         FIG. 30  is a perspective view showing an exploded view of two panels prior to forming a pocket of a cell phone case. 
         FIG. 31  is a diagram showing a typical construction of a cell phone case showing panels of material assembled to form a pocket and a cell phone being inserted into the pocket. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Shown herein as the preferred embodiment is a case for a clamshell cellular phone. One skilled in the art will recognize the construction, materials, and methods can be applied to other cases for portable electronic devices, and need not be limited to the clamshell design shown in the figures. With reference to the figures, the case  10  includes a first pocket  15  and a second pocket  20  for receiving a portion of the cell phone  11 . The case  10  includes a backbone panel  25 . The backbone panel  25  forms part of both the first pocket  15  and the second pocket  20 . The first pocket  15  includes a face sheet  30 , made of a clear material allowing a user to see the display  31  of the cell phone  1 , when the cell phone  11  is inserted into the first pocket  15 . The face sheet  30  is attached to the backbone panel  25  about part of its perimeter to form the first pocket  15 . In an alternate embodiment, intermediate side panels  35  and  36  (as used on the second pocket  20 ) are used to attach the backbone panel  25  to the face sheet  30 . The various components forming the first pocket  15  are attached to one another using heat welding, adhesive, stitching  21 , or any other construction method to join two materials known in the art. One skilled in the art will recognize that the pockets of the case  10  can be formed of any number of panels, so as to suit the shape of the phone  11  or other portable device. 
     As shown in  FIG. 3 , the panels may include a stress relief notch  39  or notches in alternate embodiments. The stress relief notch is a small cut out located in the perimeter of the panel immediately adjacent to areas where panels are joined or otherwise connected or stitched together. The stress relief notches allow the panel to stretch without overly stressing or stretching the stitched area. One skilled in the art will recognize the stress relief notches are optional, and may take on many different shapes. As shown in  FIG. 3 , the stress relief notch  39  is located adjacent the area where the backbone panel  25  and an intermediate side panel  36  are joined. It is preferred that the stress relief notches are approximately 2 to 4 millimeters wide and 2 to 4 millimeters deep. It is preferred the stress relief notches have a generally curved shape, so as to prevent formation of a stress riser as might be the case if the contours of the stress relief notch were angular. For instance, if the stress relief notch were shaped such that it included a vertex, when stressed or stretched, a tear in the panel material could begin at the vertex of the notch. 
     The backbone panel  25  can include a window  48  to allow a user to see the outside display of the cell phone  11 . The window  48  is formed of a clear material. The window  45  is joined to the backbone panel  25  by heat welding, adhesive, or stitching  21 , or any other construction know in the art. With a judicious selection of materials, the window  35  may be co-molded into the backbone panel  25  during the manufacture of the backbone panel  25 , as described herein for other structures. 
     The second pocket  20  is formed in a similar fashion, by attaching the backbone panel  25  to a front panel  37  about portions of its perimeter. As shown in the drawings, the second pocket  20  includes side panels  35  and  36 . One skilled in the art will recognize that many different configurations, panels, and places to attach the pieces together may be used to produce the first pocket  15  and second pocket  20 . 
     The first pocket  15  and second pocket  20  are to be joined by a continuous piece of material; that is the first  15  and second  20  pocket are not attached by velcro, snaps, buttons, zippers, or any other structure which allows easy detachment and reattachment from and to one another. With the single or continuous panel forming part of both pockets, a backbone panel  25  is formed linking the two pockets. 
     In use, the case  10  is placed onto the phone  11  by inserting part of the opened phone into one or the other of the first pocket  15  or the second pocket  20 . Since the face sheet  30  is typically longer than the front panel  37 , thereby creating a first pocket  15  that is deeper than the pocket formed by the front panel  37 , when donning, it is preferable to insert the phone  11  into the first pocket  15  before inserting the phone into the second pocket  20 , as shown in  FIG. 6 . The shorter length of the front panel  37  allows for easier insertion as the backbone panel  25  need not be stretched as far when compared to inserting the phone into the shorter pocket first. Unlike the prior art, which required the case to be separated into two pieces in order to be placed on the phone, the elasticity of the backbone panel  25  allows the case to be stretched far enough to allow both the first  15  and second  20  pockets to be placed on the cell phone  11  without the need to separate one pocket from the other. Thus, once the cover portion  40  of the cell phone  11  is inserted into the first pocket  15 , the user stretches the backbone panel  25  until the edge  46  of the front panel  37  clears the body portion  47  of the cell phone  11 , thereby allowing the body portion  47  to be inserted into the second pocket  20 , as shown in  FIG. 7 , The user then releases the tension on the backbone panel  25 , allowing the center portion  45  to contract, and draw the second pocket  20  over the body portion  47  of the phone  11 , as shown in  FIG. 8 . 
     Although the backbone panel  25  forms part of both the first  15  and second  20  pockets, and is one continuous piece, it need not be a uniform or homogenous piece. In other words, the backbone panel  25  may be formed of a plurality of pieces or materials attached to each other by stitching, heat welding, adhesive, or other permanent attachment. For instance, the center portion  45  can be formed of an elastic material, while the portions forming the pockets  15 ,  20  can be of a less elastic material. 
     In the preferred embodiment, the backbone panel  25  is formed by co-molding. Other parts of the case may also be formed by this process. Co-molding allows the part or panel being manufactured to easily incorporate different properties, colors, textures, shapes or other characteristics, while allowing for efficient construction. To construct the backbone panel or other part, a mold  100  is constructed. As shown in  FIG. 10 , the mold  100  is a negative mold, typically machined from a metal, such as brass. One skilled in the art will recognize the mold  100  may be created in other ways. The mold  100  may include a textured area  101  having features such as cross hashing to improve grip, piping  111 , or other physical treatment to produce and create different features upon the surface of the panel being manufactured. In some embodiments, the mold is deeper in some regions to create a thicker material in that region. 
     As shown in  FIGS. 11-13 , the panel is created in layers. To make the panel, a first substance  120  is poured into the mold  100 . In some instances the first substance  120  is the only substance used, but may be poured multiple times to cover and retain other structures such as a scrim, window, or reinforcement between the layers created. The first substance  120  and any other substance poured thereafter, may be a material such as silicone, thermosets and thermoplastics, including PVC, EPE, or any other material used in the polymer co-molding art. The first substance  120  may be poured to cover the entire mold  100  or only certain regions as shown in  FIG. 11 , depending upon the desired characteristics of the corresponding region of the panel. 
     For instance, the first substance  120  is placed in the mold  100  only in the area for piping  111 , as shown in  FIG. 14 . In other embodiments, the first substance is placed only in the area for texture. One skilled in the art will recognize the variations are unlimited. The first substance  120  is poured to a depth to cover the piping  111 , or other desired area but does not extend into the other areas where the substance is not desired. In this fashion, the first substance&#39;s  120  characteristics, such as color, will be applied only to the piping of the case or other article. 
     In the instance of the first substance  120  being EPE, the liquid EPE is placed in the desired area of the mold  100  at room temperature. The EPE is then spread out and forced into the desired areas, such as piping  111  or textured area  101 , where air voids are likely. The mold  100  containing the EPE is then heated, and then cooled to room temperature. 
     The second material  140  is then poured. The second material  140  may have different properties than the first material  120 . For instance, the second material  140  may be of a different color or texture. In some embodiments, the area of the mold  100  into which the second material  140  is poured may have a surface treatment or texture  101  to produce a surface texture on the finished product. 
     In a similar fashion, other pours may be made of either the same material, or different ones, until the panel having the desired characteristics is complete. 
       FIGS. 10 through 18  show sample configurations for panels manufactured using the co-molding process. As one skilled in the art will recognize, these are merely examples, other configurations are possible.  FIG. 10  generally depicts a mold having a textured area  101 , which will inpart a textured surface to the panel made in the mold. The textured area  101  is delineated from the non-textured area  103  by walls  104 . Walls  104  prevent the material poured into the textured area  101  from flowing into the non-textured area  103 , until the height of the walls is exceeded. In the preferred embodiment, a first layer of material occupy the textured area  101  up to the height of the walls  104 . As one skilled in the art will recognize, multiple layers could occupy the textured area  101 . 
     Shown in  FIG. 11 , a first material  120  having a first characteristic is poured into the non-textured area  103  to form a first layer of material. Subsequent to the pour of the first material  120 , a second material  140  is poured into the textured area  101  to form a first layer of the second material  140 . The layers of material both first and second, are generally co-planar, although it is not necessary. Subsequently, a third material  123  is poured over the entire mold, thus overlaying the first material  120  and the second material  140  in such a fashion, a layered panel is produced, as previously discussed, each layer of material or each pour of material can have different characteristics. When layered as to described in a mold for a backbone panel  25  as shown in  FIG. 10 , the result is a central portion of the panel having a first physical characteristic, such as texturing, and the remaining portions of the panel having no texturing. As previously discussed, variations are endless. 
     With reference to the mold shown in  FIG. 11 , a particularly useful layup of material may be used to create the backbone panel for a clamshell phone case. For the first layer, a material having a first elastic characteristic is poured in the first region, such as textured area  101 . A second material having a second elastic characteristic is poured into a second region, such as non-textured area  103 . A third pour of the second material is then poured to cover both of the previous layers of material, thereby connecting them. One skilled in the art will recognize a third material, or the first material, can be used for the third pour. Additionally, the characteristic need not be elasticity, but may be selected from the group of color, texture, additive suspended in the material, heat resistance or melting point. 
     Once the desired materials are poured and cured, the co-molded panel is removed from the mold and sewn or otherwise attached to other panels to produce the case. 
     In other embodiments, the co-molding process allows other structures to be placed or integrated into the panel. For instance, once the first substance  120  is poured, additional materials can be placed into the mold, to create a panel having areas with different characteristics. The materials may be the same substance, or include a second substance  140  for co-molding, or may include other materials or structures, such as scrims, reinforcements, or windows, judiciously placed within the mold to create areas having particular structural characteristics. 
     For instance, a scrim  130  or other woven or non-woven reinforcement may be placed in areas where there will be stitching during the assembly of the case. Such scrims are placed where the panel will be stitched to lesson the likelihood of the stitching pulling through the case material. Similarly, a scrim can be placed in the area of the aperture for the clip post, thereby reinforcing that area. In other embodiments, the window  48  is placed in the mold prior to the second material pour, thereby eliminating the need to stitch the window  48  in place, as the window will be co-molded between the first material and the second material, and thereby retained. In another example shown in  FIG. 18 , reinforcement patches  132  are placed in areas of high wear, such as edges, prior to the first pour. In other embodiments, an elastic panel is placed to connect the two pocket portions, thereby forming a portion of the continuous or backbone panel  25 . These advantages can result in significant economies during manufacture which are not possible if the material is created as a sheet, and then cut to size to form the case. If such additional structures are to be included, it is preferable that the structures are placed in the mold  100  after at least one pour has taken place, and the structure is placed over at least part of the pour, so that the structure is retained between the first and later layers of materials, However, such placement depends on the structure. The reinforcement patches  132 , may be exposed on the exterior of the panel, and hence should be in the mold prior to the first pour. 
     In other embodiments, and as a direct result of co-molding process, portions of a panel can be thicker or thinner than other sections. For instance, areas where the finished product will include stitching can easily be made thicker to prevent pull through. Other areas, such as the textured area of the mold in  FIG. 11 , or areas where the panel fits over an edge of the phone, may be thinner to provide less bulk. In other embodiments, portions of the case that fit edges of the phone may be thicker to provide impact protection. 
     In additional to the layers shown in the figures, a final lining material such as rayon, may be applied either by spraying or laminating, onto the last poured layer. The lining material allows the cellular phone, or other portable device, to easily slide into and out of the case. 
     With reference to  FIGS. 27-31 , a cell phone  11  is shown inside a cell phone case  10 . One skilled in the art will recognize the cell phone case  10  as being formed, as shown in  FIGS. 30 and 31 , of sheets of material  8  and  9  which are attached about portions of their perimeter to form a pocket  12  for the cell phone  11  or other electronic device, as shown in  FIG. 30 . Such cell phone cases are known in the prior art, and also described in the previous paragraphs of this application. The case of the present invention could also be a clamshell case as shown in  FIGS. 1-9 , and  27 - 29 , or a non-clamshell case. 
     As shown in  FIGS. 26-28 , the cell phone case  10  includes open areas  17  a-d at the corners of the cell phone case  10 .  17 a and  17 b are completely open, and do not offer protection to the corners of the cell phone  15 . 
     Areas  17 c and  17 d include strips of material  2 a-d, which divide the open areas  17 c and  17 d and provide some material over the otherwise exposed corners of the cell phone  11 . Defined another way, open areas  17 a and d include strips of material  2 a-d, thereby defining a plurality of apertures  5 a-f. One skilled in the art will recognize the number of apertures can be varied. For example, the open areas  17 c and d could include netting, or strips of material placed in different directions. 
     As shown in  FIG. 29 , the strips of material  2 c and d are part of the first panel of material  8 . The strips of material  2 a-d need not be of the same material as the first panel  8 . The strips, or other structures placed at the corners of the case, thereby protecting the corners of the electronic device in the case, can be of a different material, preferably one that will protect the device in the case from impact. Similarly, the strips of material, or other structures forming the corner protectors need not be part of the first panel  8 . The strips of material or corner protectors can be part of the second panel  9  or any other panel. 
     For example, a co-molding process, such as described previously herein, could be used to place protective structures, such as strips, molded corner protectors, netting, or other structures, at the corners of the case. These structures can be thicker than the sheets of material  8  and  9  forming the walls of the case  10 , to allow for more protection to the corners. For instance, with reference to  FIG. 30 , the corner area  51 , including strips of material  2 c and d, can be of a thicker material than the sheet of material  8 . Similarly, corner area  51  can be of a thinner material to reduce bulk. The material comprising corner area  51  can be attached to the sheet of material  8  by any known means, such as sewing, heat welding, adhesive, or more preferably, co-molding. In other embodiments, a preformed corner structure can be co-molded to the sheet of material  8  during manufacturing. 
     Is an alternate embodiment, reinforcement members or other preformed structures, that is structures molded to the contours of the case, are placed within the open areas and secured to the material or panels of the cell phone case  10  to provide protection at the corners of the electronic device or cell phone  11 . Because the structures are molded or formed, they can be made of a specific thickness that is different than the panels forming the case  10 . 
     The case  10 , no matter how produced, can include a detachable clip  200 . With reference to  FIGS. 1-5 , the detachable clip  200  is affixed to the case  10  by a post  210 . Indeed, the detachable clip  200  and post  210  can be incorporated into many different cases, not just the clamshell case  10  depicted in the Figures. This arrangement of clip and post is well known in the prior art. The post  210  includes a base  212  and an outwardly extending lug  214 . The detachable clip  200  attaches to the lug  214 , allowing the user to securely attach the case to his clothing. 
     The post  210  is removably attached to the case  10 . The case  10  includes an aperture  216  sized to allow the lug  214  to fit through yet is not large enough to allow the base  212  to pass. The post  210  is positioned so that the lug  214  extends outwardly away from the case  10 , and the base  212  remains in the case  10 , the base  212  being too large to fit through the aperture  216 . The base  212  is retained in position by a retainer  220 , the retainer  220  limiting movement and securing the base  212  when engaged. When disengaged, the retainer  220  allows the post  210  to be removed from the case  10 . 
     In the preferred embodiment, the base  212  is a generally thin, flat member, having a perimeter including two parallel straight portions  222  and two curved portions  230 . The retainer  220  is slightly thicker than the base  212 , and includes a recess  225  to receive the base  212 . The recess  225  may go entirely through the retainer  220  as an aperture. The perimeter of the recess  225  is generally concentric with the perimeter of the base  212 . The retainer  220  includes tabs  226  which extend over the base  212 , to keep the base  212  from moving in a direction perpendicular to the base  212 . In the preferred embodiment, the tabs  226  are located to extend over the curved portions  230  of the base  212 . The retainer  220  is attached to the inside of the case  10  so that it is located about the aperture  216 . The retainer  220  is attached to the case by any means known in the art, including stitching, heat weld, and adhesive. The retainer  220  could also be co-molded into the case  10 , or formed as part of the case. 
     In use, the post  210  is attached to the case  10  by inserting the lug  214  into the aperture  216  from the inside of the case. The retainer  220  is convexly flexed to allow the curved portion  230  of the base  212  to be inserted under a tab  226 . Once positioned, the retainer  220  is unflexed and the opposite curved portion  223  is allowed to snap under the remaining tab  226 , thereby securing the base  212  between the case  10  material and the tabs  226 . 
     To remove the post, the retainer  220  is again convexly flexed to snap base  212  over the tab  226 , allowing the base to be disengaged from the retainer  220  and the lug  214  to be pushed through the aperture  216 , thereby removing the post  210  from the case  10 . In such a fashion, the post  210  may be selectively attached to the case, or removed, as desired by the user. 
     One skilled in the art will recognize other structures could be used to connect a post to a retaining structure on the case. An example of such an embodiment includes a retainer  240  and base  250  that include mating structures that allow the base  250  to be separated and reconnected to the retainer  240 . 
     In the embodiment shown in  FIG. 20 , the base  250  includes a plurality of shafts  260  and  261  extending from the base  250  on the same side of the base  250  as the lug  270 . The shafts  260  and  261  are preferably positioned on either side of the lug  270  at a distance sufficient to allow of a mating structure on the retainer  240  to secure the shafts  260  and  261 . In the embodiment shown in  FIG. 20 , the shafts include a recessed portion  262  and  263  for interacting with complimentary structure on the retainer  240 , to allow the post  310  to be attached and unattached from the retainer  240 . 
     The retainer  240  includes an aperture  280  sized to allow the lug  270  to pass through. As shown in  FIGS. 20 and 21 , the aperture  280  is round. The aperture  280  may be any shape so long as the lug  270  can pass through as shown in  FIGS. 22 and 23 . Although it is preferred that the aperture  280  take a perimeter shape similarly shaped and sized to the lug  270 , such correspondence is not necessary. The outer perimeters of the base  250  and the retainer  240  are generally co-extensive, although either structure may be larger or smaller than the other. In instances where the base  250  perimeter extends beyond the perimeter of the retainer  240 , the portion of the base  250  extending is raised so as to form a lip about portions of or about the entire perimeter of the retainer  240 . 
     The base  250  can also include separation recesses  320  and  321  at its perimeter. The separation recesses are areas exposed to the perimeter that are of reduced thickness. When the base  250  and retainer  240  are mated, the separation recesses allow space between the two structures to allow a fingernail or other object to lever the two structures apart. 
     The retainer  240  includes a plurality of receivers  290 ,  291  for receiving and engaging the shafts  260  and  261 . In the embodiment shown in  FIGS. 20 and 21 , the receivers  290  and  291  include members or tabs  294  a and b and  295  a and b to engage the recessed portions  263  and  262  of shafts  260  and  261  when the shafts  260  and  261  are inserted into the receivers  290  and  291 . In the embodiment shown, the tabs  294  a and b and  295  a and b include a resilient portions  300  a-d attached to the retainer  240 . The resilient portions  300  a-d flex to allow arc portions  311  a-d to slide over the distal end of the shafts  260  and  261  and seat in the recesses  262  and  263 . One skilled in the art will recognize that other types of arranged could be used to secure the posts  260  and  261  to the retainer  240 . 
     In an alternate embodiment shown in  FIG. 22 , the aperture  280  in the retainer  240  is rectangular. Additionally, the lug  270  includes a portion  330 , which is shaped to compliment and fit inside of aperture  280 . Such engagement prevents or reduces relative movement between the retainer  240  and base  250  in a direction parallel to the major plane of the retainer  240 , thus reducing forces applied to the receiver  291  and  290 , which might cause undesired separation of the base  250  from the retainer  240 . One skilled in the art will recognize other non-circular shapes will also accomplish the same stability and prevent rotation of the lug  270  in the aperture.  FIG. 23  also shows a retainer  240  with a perimeter flange  299 . 
     As shown in  FIG. 24 , an alternate base  400  includes a raised portion  410 , but does not include a lug or post for attachment of a clip. Such a base  400  is used to occupy or otherwise obstruct the aperture  280  when the base with the lug is removed. Use of the alternate base  400  thus renders a case without the projecting lug or post, resulting in a generally smooth case. The portion of the base  400  visible through the aperture  280  can include indicia  420  such as advertising, logos, or other indications of sponsorship. 
     One skilled in the art will recognize that other types of constructions may be utilized in attaching the post to the case. One such constructive is a bayonet mount, as shown in  FIGS. 25 and 26 . The post  500  is attached to a mounting base  510 . The mounting base  510  includes an aperture having a plurality of notches  522  a-d about its perimeter. The notches  522  a-d are sized and spaced so as to accept projections  525  a-d position about the bade of the post  500 . The bottom  530  mounting base  510  is attached to the outside surface of the case by stitching adhesive, rivets, or other means of mechanical attachment. When attached to the outside of the case, the use of the bayonet mount allows the post  500  to be inserted and removed from the outside of the case. Thus, the case does not need an aperture. 
     In use, the post  500  is inserted into aperture base end  540  first, such that projections  525  a-d are inserted into notches  522  a-d. Adjacent notches  525  a-d are flanges  535  a-d. The flanges are generally arcuate in shape and form part of the aperture  520  perimeter, thus restraining the post  500  from side to side movement. The flanges  535  a-d are of a thickness less than the thickness of the base  510 , so as to accommodate the projections  525  a-d when the post  500 . The base  510  also includes stops  545  a-b on the flanges  535  a-b so that rotation of the post is stopped, preventing over rotation of the post  500 . 
     The embodiments disclosed herein are illustrative of the invention and are not meant to limit the scope of the invention.