Abstract:
A method and apparatus for making inexpensive, form-fitted, protective cases of thermal plastic or polycarbonate material that can be easily printed with decorative imagery and/or electronic circuitry for a variety of products, such as portable music players or radios, cell phones, lap-top computers, and the like. The method involves creating a tool having substantially the same surface dimensions of a product. An element is then molded from bulk film of thermoplastic material using the tool. Once the element is molded, it is trimmed from the bulk film. The resulting apparatus is a protective case intended to form-fit over the surface features and dimensions of the actual product used to define the tool.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates generally to the making of form-fitted, molded protective cases for products, and more particularly, to a method and apparatus for making inexpensive, form-fitted, protective cases made from a polycarbonate or thermoplastic material that can be readily printed with decorative imagery and/or electronic circuitry. The protective cases can be made for a variety of products, such as portable music players, radios, cell phones, lap-top computers, and the like.  
       BACKGROUND OF THE INVENTION  
       [0002]     A variety of consumer electronic products, such as portable music players like the Ipod™ from Apple Computer, lap-tops, cell phones, etc., have become extremely popular in recent years. Since these devices are all portable, they are typically carried or otherwise accompany a person to and from work, while traveling, working out or exercising, socializing, etc. The portability of these products makes them convenient, but typically at the expense of added wear and tear on the product. Very often these products are dropped by accident, get bang or bounced around, causing the exterior to be scratched or damaged. For some products, it is known to use a carrying case to both carry and protect the product. These cases, however, are typically made of leather, silicon rubber, or nylon, are non-decorative, and are clumsy to use. It is often difficult to insert and remove the product from the case.  
         [0003]     Both manufacturers and consumers of many portable electronic devices are also extremely brand conscience. For example, companies like Apple Computer and Nokia have developed very strong brand awareness associated with their Ipod™ and cell phone product offering respectively. These organizations go to great lengths to appropriately brand their products with decorative company logos, trademarks, and the like.  
         [0004]     One known method of forming art work on the exterior case of a product is called In Mold Decoration or (IMD). With this technique, a hard plastic element that is shaped to form-fit over a product or a portion of a product is created. The hard plastic element may be formed in a number of ways, for example by milling, using a mold, etc. After the element has been fabricated, it is placed into a mold with a film containing the art work. Structural plastic is then injected into the mold, causing the hard element and the film containing the art work to bond. After removal from the mold, the element with the bonded art work is then placed onto the product or portion of the product it was intended to cover. The element with the art work typically becomes an integral part of the product, meaning it is affixed to the product in some way, such as snapping or screwing it onto the body of the product. While beneficial, the aforementioned process has a number of drawbacks. Foremost it is very expensive. The hardened element must be made for each product. This will often require the creation of a specific mold for each element to be used with a product. Secondly, since the element becomes an integral part of the product, it does not provide a protective cover for the product.  
         [0005]     Accordingly, a method and apparatus for making inexpensive, form-fitted, protective cases of polycarbonate or thermal plastic material that can be easily printed with decorative imagery and/or electronic circuitry for a variety of products, such as portable music players or radios, cell phones, lap-top computers, and the like, is therefore needed.  
       SUMMARY OF THE INVENTION  
       [0006]     To achieve the foregoing, and in accordance with the purpose of the present invention, a method and apparatus for making inexpensive, form-fitted, protective cases of thermal plastic or polycarbonate material that can be easily printed with decorative imagery and/or electronic circuitry for a variety of products, such as portable music players or radios, cell phones, lap-top computers, and the like, is disclosed. The method involves creating a tool having substantially the same surface dimensions of a product. An element is then molded from bulk film of thermoplastic material using the tool. Once the element is molded, it is trimmed from the bulk film. The resulting apparatus is a protective case intended to form-fit over the surface features and dimensions of the actual product used to define the tool. In various embodiments, the bulk film can be pre-printed with a decorative image or electronic circuit prior to molding. As a result, the image or circuitry appears on the element after it is molded.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]     The invention, together with further advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings in which:  
         [0008]      FIG. 1  is a diagram of an music player tool used for fabricating protective cases according to the present invention.  
         [0009]      FIG. 2  is a diagram of a protective case made by the tool of  FIG. 1  according to the present invention.  
         [0010]      FIG. 3  is a diagram for fabricating the protective case according to one embodiment of the present invention.  
         [0011]      FIG. 4  is a diagram for fabricating the protective case according to another embodiment of the present invention.  
         [0012]      FIG. 5  is a diagram for fabricating the protective case according to another embodiment of the present invention.  
         [0013]      FIG. 6  is a diagram for fabricating the protective case according to another embodiment of the present invention.  
         [0014]      FIG. 7  is a diagram for fabricating the protective case according to another embodiment of the present invention.  
         [0015]      FIG. 8  is a diagram showing a molded element before being trimmed from the bulk film according to one embodiment of the present invention.  
         [0016]      FIG. 9  is a diagram illustrating the trimming of the molded element from the bulk film according to the present invention.  
         [0017]      FIGS. 10A and 10B  illustrate a sheet of bulk material and a molded element fabricated thereon having a decorative logo printed thereon respectively according to the present invention.  
         [0018]      FIG. 11  illustrates a molded element with a printed logo fitted over an Apple Ipod™.  
         [0019]      FIG. 12  illustrates a molded element having a conductive circuit printed thereon according to the present invention.  
         [0020]      FIG. 13  is a flow diagram illustrating the sequence of making the protective case of the present invention.  
         [0021]      FIG. 14  is a diagram illustrating the receipt and printing of an image onto the bulk film used to make the molded elements according to the present invention. 
     
    
       [0022]     In the Figures, like reference numbers refer to like components and elements.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0023]     Referring to  FIG. 1 , a diagram of a tool of a music player used for fabricating protective cases for an actual music player according to the present invention is shown. The tool  10 , for the sake of illustration, resembles an Apple Ipod™. The tool can be made from a variety of materials such as plastic, metal, wood, etc. The tool can also be fabricated in a variety of ways, including milling, molding or three dimensional printing The key feature of the tool is that its external features and dimension be substantially identical to the actual product the case is intended to cover and protect. In the illustrated example for instance, the tool includes a surface bump  12  having substantially the same height and diameter as the “Apple Click Wheel”, and openings  14 ,  16  and  18 , corresponding to the hold switch, remote port and headphone jacks on an actual Apple Ipod™ respectively. It should be noted that the tool  10  as shown is merely illustrative. In accordance with the present invention, the tool could be shaped to be substantially similar to virtually any product or object.  
         [0024]     Referring to  FIG. 2 , a diagram of a protective case according to the present invention is shown. The tool  10  is used to mold the protective case  20  so that it will form-fit an actual Apple Ipod™. The protective case  20  includes a front member  22  intended to be placed over the front of an actual Ipod™ and a second back member  24  intended to be placed over the back of the Ipod™. The front member  22  includes a surface bump  24  to accommodate the Click Wheel of the Ipod™. Both the front member  22  and back member  24  include recess regions  26   a ,  27   a , and  28   a  and  26   b ,  27   b , and  28   b  to accommodate the hold switch, remote port and headphone jacks on an actual Apple Ipod™ respectively.  
         [0025]     In various embodiments, the two members  22  and  24  of the protective case  20  are made from a bulk film of a thermoplastic or polycarbonate material. A thermoplastic is any plastic material that becomes soft and compliable when heated and hard when cooled. Examples of thermoplastics that can be used with the present invention include acrylonitrile butadiene styrene, polyvinyl chloride (PVC), polypropylene, acrylic, celluloid, etc. A polycarbonate is a class of thermoplastics characterized by high-impact strength and light weight. The material can be either clear, colored, or opaque. In one specific embodiment, the material used is a thermoplastic such as Lexan™, available from General Electric Corporation. As described in more detail below, the raw material used to make the protective case  20  is initially in large bulk film form. The film is subsequently molded, using any one of a variety of machines and techniques, that rely on pressure, heat, or a combination thereof, to mold the material to the shape of the tool  10 . A trimming machine is then used to excise or cut the case  20  from the bulk film.  
         [0026]     Referring to  FIG. 3 a  diagram of a machine used for fabricating the protective case according to one embodiment of the present invention is shown. In this embodiment, a film  30  is placed over the tool  10 . A heating element  32  is then used to heat the film  30  and tool  10  while a vacuum  34  is used to pull the film  30  onto the tool  10 . This process is highly versatile and inexpensive. Both male and female shaped tools can be used.  
         [0027]     Referring to  FIG. 4 , a diagram for fabricating the protective case according to another embodiment of the present invention is shown. This embodiment relies on pressure to assist in the molding process and is more advanced than simply using heat and a vacuum. In this process, a clamp  42  is used to clamp the film  30  over the tool  10 . Air pressure is then applied to the top of the film while a vacuum is applied to the bottom of the film. This results in improved molding definition, increased consistency, and better replication for a better fit. Both male and female molds can be used.  
         [0028]     Referring to  FIG. 5 , a diagram for fabricating the protective case according to another embodiment of the present invention is shown. In this embodiment, a zero gravity fabrication machine  50  is used. The fabrication machine  50  includes a vacuum chamber  52 . The tool  10  is placed within the chamber  52  and the film  30  is placed over the tool  10  and under a heating element  54 . Air is then purposely introduced inside the chamber  52  to compensate for the natural sag of the heated film  30 . The zero gravity fabrication machine  50  tends to retain the uniformity of the film thickness after the protective case has been fabricated. This technique is particularly useful for the fabrication of large protective cases.  
         [0029]     Referring to  FIG. 6 , a diagram for fabricating the protective case according to another embodiment of the present invention. In this embodiment, a hydro-forming tool  60  uses a pressurized bladder  62  to exert pressure and force the film  30  onto the tool  10 . The pressure causes the film  30  to assume the shape of the tool  10 .  
         [0030]     Referring to  FIG. 7 , a diagram for fabricating the protective case according to another embodiment of the present invention is shown. In this embodiment, the film  30  is squeezed between a male tool  10   a  and a female tool  10   b . The pressure on the film  30  created during the squeezing action causes the film  30  to assume the shape of the tools  10   a  and  10   b.    
         [0031]     Referring to  FIG. 8 , a diagram illustrating a molded sheet  30  including a molded element  22  formed thereon is shown. The element can be molded using any of the aforementioned machines or methods. The molded sheet has excess bulk material  82  surrounding the molded element  22 . It should be noted that in the embodiment illustrated, only a single element  22  is shown. It should be understood that according to other embodiments, multiple elements  22  or  24  could be fabricated on the sheet  30 , either serially or in parallel. When the element is molded in a serial fashion, the bulk sheet  30  is typically stepped, aligned, and molded. This sequence is repeated over and over. Alternatively, the elements  22  and/or  24  could be molded in parallel using a machine capable of molding one or more elements simultaneously. With such a machine, the film would again be stepped, aligned, and then multiple elements would simultaneously be molded in the machine.  
         [0032]     Referring to  FIG. 9 , a diagram illustrating the element  22  trimmed from the bulk sheet  30  is shown. According to various embodiments, the trimming machine used to excise the element  22  from the sheet  30  can be capable of either cutting in two dimensions in the X and Y directions or cutting in three dimensions along the X, Y and Z directions. In the example illustrated, the element  22  is trimmed or cut from the sheet  30  along the Z axis around the perimeter  90  of the element  22 . The trimming can be performed using for example steel rule die cutting, matched metal dies, or laser trimming. As a general rule the steel rule die cutting would be used for two-dimensional elements whereas the matched metal dies would be used for three dimension elements.  
         [0033]      FIGS. 10A and 10B  show yet another embodiment of the present invention. With this embodiment, the bulk sheets  30  are printed with decorative imagery. In the example shown, the image is the logo for the NY Yankees baseball team. It should be noted, however, that the sheet  30  can be printed with any logo or imagery, such as but not limited to a sports team logo, the logo of a popular product such as Coca Cola or Harley Davidson, a flag or other patriotic symbol, a photograph, or any other desirable image. The bulk sheets  30  can be printed in one of a variety of ways, such as using a digital press, silk screening, four color press, or any other printing process.  
         [0034]     Referring to  FIG. 11 , a diagram illustrating elements  22  and  24  with the NY Yankee logo printed thereon is shown. The two elements are placed over and used to protect an Apple Ipod™ 110. Again it should be noted that the elements  22  and  24  can be molded to form-fit any product, and not just the Apple Ipod™ as illustrated.  
         [0035]     Referring to  FIG. 12 , a molded element having a conductive circuit printed thereon is shown. The element  120  has a metal circuit  122  that is printed thereon. According to various embodiments, the metal circuit can be made from any conductive material, such as aluminum or gold. It can be printed onto the element  120  prior to its being molded while still in bulk film form. For example, the metal circuit can be printed onto the film in a number of ways, for example by silk screening, digital press, color press, or any other printing process capable of printing a conductive metal or ink. The circuit  122  can be any type of circuit, for example an antenna for a cell phone or a portable radio. In other embodiments, the printed circuit can be used for implementing a touch sensitive control surface or status indicator, etc. with the addition of discrete components (such as resistors, diodes, ICs. In yet another embodiment, a second element  124  may be used to cover the first element  120  with the printed circuit  122  formed thereon. The second element is form-fitted to the first element  120  and is designed to fit over and protect the printed circuit  122 . The second element  124  can be either transparent, opaque, colored, and/or have a decorative logo or imagery formed thereon.  
         [0036]     Referring to  FIG. 13 , a flow chart illustrating the sequence of making elements configured to form-fit another product is shown. In the initial step, the tool  10  is fabricated (box  132 ). Next the image to appear onto the elements is defined (box  134 ) and then printed onto the bulk sheet  30  (box  136 ). Thereafter, the sheet is molded using any of the above described techniques to form the elements (box  138 ). In the final step, the bulk sheet material is trimmed (box  140 ), excising the elements from the bulk material.  
         [0037]     Referring to  FIG. 14 , a diagram illustrating the receipt and printing of an image onto the bulk film used to make the molded elements according to the present invention is shown. In the diagram, an end user, such as a customer, using a computer  140  uploads an image file to a server  142  via a computer network  144 , such as the Internet. The server  142  then manipulates the file as necessary and provide the image file to a digital printer  146 . The image defined by the image file is then printed onto the bulk film material  30 . After the image is printed, the film  30  can be molded using any of the above-described embodiments. In this manner, protective case for a product with virtually any image printed thereon can be easily and readily made. For example, a favorite photograph, image, logo, etc. can be printed onto the protective case.  
         [0038]     Although the foregoing invention has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the appended claims. Therefore, the described embodiments should be taken as illustrative and not restrictive, and the invention should not be limited to the details given herein but should be defined by the following claims and their full scope of equivalents.