Abstract:
An integrated protective apparatus extruded from a PVC material for semi-rigidly attaching a planar protective element to a lens assembly and chassis in a projection television (PTV). The apparatus includes a plurality of channels, each configured to accept one or more of a plurality of lenses or protective elements. The apparatus can include molded protrusions that can be arranged to apply a retentive force against the lenses and protective elements supported within the channels.

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 60/275,392, filed Mar. 13, 2001. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to the field of projection televisions, and more particularly to an apparatus for protecting a cathode ray tube during storage and shipment. 
     BACKGROUND OF THE INVENTION 
     In projection television (PTV) applications, a high intensity light beam with a video image is projected through a series of lenses onto a viewing plane. To preserve image quality, the surfaces of the lenses must be kept free of dirt, dust, and smudges that can result from direct handling of the PTV during movement and storage. 
     Consequently, an additional planar protective element is typically attached over the surfaces to be protected during the manufacturing and shipping process and removed when the PTV is installed at a destination location. Conventional protective planar elements are typically attached to the PTV using adhesive or mechanical fastening elements. This results in time being added to the manufacturing and installation process, which together with the adhesives and fastening elements add unnecessary cost to the finished PTV. 
     Fasteners and spacers are conventionally used to mount the lenses in a PTV chassis enclosure. However, at present, such conventional mounting apparatus do not include means for holding a protective element It is therefore an object of the present invention to provide such an apparatus which will eliminate the need for a separate manufacturing step to add the protective element, thereby reducing the number of fabrication steps, the materials required, and thus the cost of a PTV. 
     SUMMARY 
     An integrated support apparatus for semi-rigidly attaching a planar protective element to a lens assembly and chassis in a projection television (PTV). The apparatus can be extruded from a PVC material. The apparatus includes an attachment interface comprising a multitude of channels each being constructed to accept in mating arrangement one or more lenses and/or protective elements along an edge dimension of the lenses and/or protective elements. 
     The apparatus can include molded protrusions that can be arranged to apply retentive pressure against major planar surfaces of the lenses and/or protective element to be attached and supported in the receiving channels. Both rigid structural elements and resilient padding elements of the apparatus can be manufactured together by simultaneously co-extruding a rigid PVC material and a resilient PVC material, respectively. The apparatus can further include protrusions for special separation boundaries in the PTV. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a side view of a first exemplary embodiment of a mounting apparatus for a projection television (PTV) for mounting a plurality of lenses and a protective planar element in a predetermined spatial arrangement according to the present invention. 
     FIG. 2 shows a perspective view of a section of the mounting apparatus shown in FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a side view of an exemplary embodiment of a mounting apparatus  10  for selectively mounting a planar protective element  12  over an exterior surface of a focal assembly of a projection television (PTV) in a predetermined spatial arrangement according to the present invention. Element  12  is clear, thereby enabling the PTV to be viewed without having to remove element  12 . Apparatus  10  is permanently mounted to the PTV, with protective element  12  able to be selectively removed from said apparatus. 
     The focal assembly, which is comprised of a plurality of projection lenses, e.g., a fresnel lens  14  and a lenticular lens  16 , is preferably supported and retained in a channel-like mounting slot  18  in a generally rigid manner. Similarly, protective element  12  is supported and retained in a second channel-like mounting slot  20 . Apparatus  10  can include any number of mounting slots. One or more resilient pads  22  can be added to apparatus  10  to cushion the interfaces of the focal assembly and protective element  12 , respectively, from the weight of such elements. Pads  22  are not required in all applications, and their use will depend on the characteristics of a particular element being supported, i.e. weight, fragility, etc. Pads  22  can be separately attached when used. 
     A first resilient, semi-rigid protrusion  24  is preferably included to hold the focal assembly in place with sufficient lateral force in mounting slot  18 , so that lenses  14  and  16  cannot move, either as an integrated focal assembly or one lens relative to the other. Planar protective element  12  can also be frictionally supported to the same degree using second resilient protrusion  26 . The structure of protrusions  24  and  26  can be designed so that they exert sufficient lateral pressure in the desired direction. This will normally involve either an angular orientation of protrusions  24  and  26  relative to the mounting plane and/or a curved or coiled structural arrangement. As shown in the figures, the semi-rigid protrusions are curved along parallel inner and outer surfaces. 
     Apparatus  10  can also include predetermined spacing or gaps between protective element  12  and lenses  14  and  16 , using planar separating protrusions that comprise the outer walls of mounting slots  18  and  20 . Such spacing prevents protective element  12  and lenses  14  and  16  from being damaged during drops, bumps and routine movement of the PTV. FIG. 1 shows an exemplary 1.5 mil air gap  28  between the front of the lens assembly and protective element  12 . It should be noted that although FIG. 1 shows a non-spacer arrangement between fresnel lens  14  and lenticular lens  16 , a particular application can include spacers and still be within the scope of the invention. To properly fit and secure apparatus  10  within a PTV chassis, various standoffs  30  and hooks or snaps  32  can also be included as part of apparatus  10 . As shown in the figures, both the chassis snap connector  32  and the standoffs  30  are isolated from the first and second semi-rigid protrusions. In addition, in the illustrated embodiment, the chassis snap connector is oriented at an orthogonal angle with respect to the mounting slots. 
     FIG. 2 shows a perspective view of a section of the mounting apparatus  10  shown in FIG.  1 . As shown in FIG. 2, apparatus  10  includes slots  18  and  20  for receiving and retaining the focal assembly comprised of fresnel lens  14  and lenticular lens  16 , and planar protective element  12  with separator  34  juxtaposed between them. Like the other components of apparatus  10 , separator  34  is an extruded component. The finished apparatus  10  is then cut to an appropriate length. 
     Apparatus  10  can be quickly and inexpensively fabricated using conventional extrusion methods. Apparatus  10  is preferably fabricated from extruded PVC, although it can be fabricated from any similar material. Pads  22  are preferably fabricated from a heat-resistant and chemically treated portion of apparatus  10 . Alternatively, pads  22  can be fabricated from simultaneous co-extrusion of a flexible PVC material and a rigid PVC material. 
     Once apparatus  10  is fabricated, lenses  14  and  16  can be installed in mounting slot  18  in a clean-room environment to prevent dust contamination of the assembly. The lens/mounting slot assembly can then be installed in the PTV chassis. After the lens/mounting slot assembly is installed, planar protective element  12  can be installed into slot  20 . The PTV will then be ready for shipment and/or storage, with protective element  12  being removed from apparatus  10  when the PTV is to be used. 
     Numerous modifications to and alternative embodiments of the present invention will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best mode of carrying out the invention. Details of the embodiments may be varied without departing from the spirit of the invention, and the exclusive use of all modifications which come within the scope of the appended claims is reserved.