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[0001]    This application is being filed as a PCT International Patent Application in the name of Kent A. FORSLAND, a U.S. citizen and resident, on Apr. 6, 2001, designating all countries.  
         FIELD OF THE INVENTION  
         [0002]    The present invention generally relates to doors used to selectively open and close openings in structures. More specifically, the present invention relates to doors used with buildings having doorways located in a vertical position to close the doorway and a horizontal position to open the doorway.  
         BACKGROUND OF THE INVENTION  
         [0003]    Doorways in antiquated garages are closed with swinging garage doors attached to upright supports with hinges. These doors must be moved outwardly to open the doorway. The swinging doors require ground and head clearances to allow the doors to open and close.  
           [0004]    In order to obviate the clearance requirements of the swinging doors, lateral roll doors were developed. The lateral roll doors have a number of vertical sections hinged together in side-by-side relation. The doors are supported on right angle tracks for movement along the tracks between a closed position and an open position. The tracks are mounted on headers above the doorways and also include side supports extending inwardly to the part of the garage where vehicles are typically housed. This typical arrangement of lateral roll doors makes it difficult to access and egress the garage when a side of the vehicles is located adjacent the doors in the open position.  
           [0005]    Roll-up overhead doors were developed to reduce the access and egress problems. Typically, roll-up overhead doors have horizontal sections hinged together between sections. Rollers mounted on the sections engage side tracks having vertical and horizontal sections to locate the door in a vertical closed position and an overhead horizontal position. An example of a roll-up garage door having hinged sections is shown in U.S. Pat. No. 5,168,915. These roll-up doors are heavy and, in some cases, have been usually not efficient at keeping the elements out of the interior of the garage. Improvements are desired.  
         SUMMARY OF THE INVENTION  
         [0006]    The invention of the present application relates to a lightweight, strong, and economical overhead door having a plurality of transverse sections for closing a doorway in a structure, such as a garage. Each section comprises a one-piece, sturdy rigid structure that has a high strength against bending and twisting. Adjacent sections are connected with hinges to allow the door to articulate from a vertical position to a horizontal position as it moves along side tracks supporting the door adjacent a doorway. Preferably, each section is a rigid, laminated panel having a foam plastic core bonded to an inside sheet member and an exterior sheet member. Typically, the inside sheet member comprises plywood sheet bonded with an adhesive to one side of the core. Typically, the exterior sheet member comprises an exterior siding, for example, cedar siding, bonded with an adhesive to the opposite side of the foam plastic core. Border members located between the peripheral edges of the sheet members surround the foam plastic core. One or more sections may include a window assembly. The window assembly typically includes means for framing a window pane. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]    [0007]FIG. 1 is a front elevational view of an example embodiment of a roll-up door;  
         [0008]    [0008]FIG. 2 is a side elevational view of the door of FIG. 1;  
         [0009]    [0009]FIG. 3 is a rear elevational view of the door of FIG. 1;  
         [0010]    [0010]FIG. 4 is a top plan view of FIG. 3;  
         [0011]    [0011]FIG. 5 is a bottom plan view of FIG. 3;  
         [0012]    [0012]FIG. 6 is an enlarged sectional view taken along line  6 - 6  of FIG. 1;  
         [0013]    [0013]FIG. 7 is an enlarged sectional view taken along line  7 - 7  of FIG. 1;  
         [0014]    [0014]FIG. 8 is an enlarged sectional view taken along line  8 - 8  of FIG. 1;  
         [0015]    [0015]FIG. 9 is an enlarged foreshortened sectional view taken along the line  9 - 9  of FIG. 1;  
         [0016]    [0016]FIG. 10 is a front elevational view of a second example embodiment of a roll-up door;  
         [0017]    [0017]FIG. 11 is a side elevational view of the door of FIG. 10;  
         [0018]    [0018]FIG. 12 is an enlarged sectional view taken along line  12 - 12  of FIG. 10;  
         [0019]    [0019]FIG. 13 is a rear elevational view of the door of FIG. 10;  
         [0020]    [0020]FIG. 14 is a top plan view of FIG. 12;  
         [0021]    [0021]FIG. 15 is a bottom plan view of FIG. 12;  
         [0022]    [0022]FIG. 16 is a front elevational view of a third example embodiment of a roll-up door;  
         [0023]    [0023]FIG. 17 is a side elevational view of FIG. 16;  
         [0024]    [0024]FIG. 18 is a rear elevational view of FIG. 16;  
         [0025]    [0025]FIG. 19 is a top plan view of FIG. 18;  
         [0026]    [0026]FIG. 20 is a bottom plan view of FIG. 18;  
         [0027]    [0027]FIG. 21 is an enlarged front plan view of the top section of the door of FIG. 16 showing a window assembly; and  
         [0028]    [0028]FIG. 22 is an enlarged foreshortened sectional view taken along line  22 - 22  of FIG. 21. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0029]    One example embodiment of a roll-up door  20  is shown in FIGS.  1 - 5 . Door  20  includes an upper section  21  and a lower section  22  pivotally coupled using one or more hinges  23 ,  24  and  25 . One or more brackets  26 ,  27  are secured to opposite upper corners of the portion of section  21  located inside the garage when door  20  is in the closed position. Support brackets  28 ,  29  are mounted on opposed corners of inside portion of section  22 . Rollers (not shown) mounted on hinges  23  and  25  and brackets  26  and  29  movably support door  20  on tracks that guide door  20  between open and closed positions.  
         [0030]    In the example embodiment shown, upper section  21  is a one-piece laminated panel further including one or more window assemblies  31 ,  32 . However, there are many alternative window assemblies can be used with section  21 . For example, a single window assembly or multiple window assemblies may be incorporated in section  21 . The size and arrangement of the window assemblies can vary to fit the length and height of section  21 . In another example embodiment, upper section  21  is a solid continuous panel without window assemblies.  
         [0031]    One example embodiment of paneling of section  22  is shown in FIGS.  6  to  8 . Section  22  includes a flat internal core  33 . Preferably, core  33  is fabricated from expanded or foamed plastic. Preferably, core  33  is a continuous body of rigid polystyrene or rigid expanded polyurethane. However, many other types of foamed, closed-cell plastic can be used to fabricate core  33 . In the example embodiment shown, a plywood sheet member  34  is coupled with a layer of adhesive  36  to a first surface  300  of core  33 , preferably using an adhesive  36 . Alternatively, other coupling methods can be used, depending on the overall appearance desired for door  20 . Member  34  may be a 0.25 inch plywood sheet having a finished outer surface  340  that is generally planar. An outer sheet member  37  typically is coupled with an adhesive  38  to a second surface  302  of core  33 . One example of outer sheet member  37  is 0.375 inch, 3-ply siding. In another example, sheet member  37  is 0.375 inch medium density overlay. As shown in FIGS. 6 and 7, one or more linear border members  39 ,  41  are located between the peripheral edge portions of sheet members  34  and  37 . In the example embodiment shown, border members  29  and  41  are coupled to sheet members  34  and  37  with adhesive  36 ,  38 . Upper section  21  further includes first edge  401 , a second edge  401 , a third edge  403  and a fourth edge  404 . Generally, sheet members  34 ,  37  have edges located coextensive with the corresponding edge of section  21 .  
         [0032]    Referring to FIG. 8, section  22  includes a stepped border member  43  having a first surface  430  and a second surface  432 . First surface  430  of border member  43  typically is coupled to sheet member  34  using adhesive  36 . Second surface  432  of border member  43  also typically is coupled to sheet member  37  using adhesive  38 . Border members  39 ,  41 ,  43  surround core  33  and engage flat outer peripheral surfaces of core  33 . In the example embodiment shown, border members  39 ,  40  and  41  are coextensive with the outer edges of sheet members  34  and  27 . Lower section  22  further includes a first edge  405 , a second edge  406 , a third edge  407  and a fourth edge  408 . Generally, sheet members  34 ,  37  have edges located coextensive with the corresponding edge on the section  22 .  
         [0033]    One method of fabricating section  22  includes arranging core  33 , sheet members  34 ,  37 , border members  39 ,  41 ,  43  and adhesive  36 ,  38  in their preferred positions and subjecting the entire assembly to pressure. This method provides for sheet members  34 ,  37  and border members  39 ,  41 ,  43  to be coupled to core  33 . One advantage of the described structure is that section  22  is a strong and rigid and relatively light weight structure that has substantial strength against bending and twisting. Another advantage is that reinforcing webs and ribs are not required to inhibit horizontal and vertical bending of the section  22 , thus reducing manufacturing cost as well as reducing the labor and materials required to fabricate door  20 . Another advantages is that material used for core  33  provides door  20  with sound and thermal insulation.  
         [0034]    Upper section  21  has essentially the same laminated panel structure as lower section  22 . Parts of the panel of section  21  that correspond with the parts of the panel of section  22  have the same reference numbers with the leading digit  4 . The bottom border member  443 , as shown in FIG. 8, includes a reverse or downward facing step border member  44  is located adjacent to and is shaped complimentary to the step of border member  43 . When door  20  is in the closed or upright position, step surfaces of border members  43  and  443  contact each other, thereby inhibiting air, water, snow and dirt from flowing through door  20 .  
         [0035]    Referring to FIGS. 1 and 9, window assembly  31  fits in a rectangular hole  46  cut into the panel of section  21 . Window assembly  32  is located in similar rectangular hole in section  21 . Window assembly  31  includes a first-frame  47  having an outside flange  48  coupled to sheet member  237 . The flange  48  is joined to a rectangular body  49  having an inwardly directed shoulder  50 . A vertical transparent pane  51 , for example glass or plastic, fits in body  49  and engages shoulder  50 . A lower surface  52  of body  49  slopes downwardly and outwardly from pane  51  to allow water to drain away from pane  51 . A second frame  53  retains pane  51  on body  49 . Frame  53  has an outwardly directed flange  54  secured with one or more fasteners  56 , for example, bolts, to sheet member  434 . Flange  54  is joined to a rectangular body  57  that telescopes into body  49  and contacts pane  51 . Second frame  53  can be removed from the first frame  47  if it is necessary replace broken pane  51 . Window assembly  32  has substantially the same structure as window assembly  31 .  
         [0036]    Another example embodiment of a roll-up door  100  is shown in FIGS.  10  to  15 . Door  100  includes four rectangular sections  101 ,  102 ,  103  and  104 . Adjacent sections are pivotally connected with hinges  106 - 114 , as shown in FIGS. 11 and 12. Section  101 - 104  each include rigid panel construction, as shown in FIGS. 6 through 9. A cross section of the panel of section  103 , shown in FIG. 12, includes a plywood sheet member  116  secured with an adhesive  117  layered to an core  118 . Preferably, core  118  is fabricated from an expanded plastic, for example Styrofoam or expanded polyurethane.  
         [0037]    Referring to FIGS. 10 and 12, outside sheet member  119  can be fabricated from many different materials, depending on the appearance desired for door  100 . In the embodiment shown, the appearance could be accomplished by using, for example, grooved cedar siding. Sheet member  119  is coupled to core  118  with layer of an adhesive  121 . An outside surface  419  of sheet member  119  includes a vertical groove  122 . In the embodiment shown, sheet member  119  includes a plurality of horizontally spaced vertical grooves  122 , as shown in FIG. 10. Sections  102  and  104  include corresponding vertical grooves  122  that are vertically aligned with the grooves in sheet member  119 . The panels of sections  102  and  104  have the same structure as section  103  as shown in FIG. 12. An advantage of this example embodiment is sections  102 ,  103  and  104  are flat, strong, sturdy and light weight structures.  
         [0038]    Referring to FIGS. 10 and 13, upper section  101  has a pair of window assemblies  123  and  124 . In the example embodiment shown, window assembly  123 ,  124  has three glass panes. The number of window assemblies and glass panes in each window assembly can vary, depending on the appearance desired for door  100 . Each window assembly can have a single glass pane as shown in door  20  in FIGS. 1 and 3. Window assemblies  123  and  124  have frames  126  and  127  and glass pane  128  structures shown in FIG. 9. The window assembly shown in FIGS. 21 and 22 can be mounted on upper section  101 .  
         [0039]    Referring to FIGS.  16  to  22 , is shown a second example embodiment of a door  200 . Door  200  includes the rigid panels shown in FIGS.  6  to  8  in rectangular door sections  201 ,  202  and  203 . As seen in FIGS. 18 and 19, adjacent section  201  and  202  and  202  and  203  are pivotally connected with hinges  204 ,  205 ,  206 ,  207 ,  208  and  209 .  
         [0040]    Upper section  201  has a pair of window assemblies  211  and  212 . Trim members  213 ,  214 ,  215  and  216  secured to the front of flat panel  217  surrounding window assemblies  211  and  212 . Upper section  201  can have a single window assembly or more that two window assemblies, depending on the appearance desired for door  200 .  
         [0041]    Middle section  202  includes a flat panel  218 . Horizontal and vertical trim members  219 ,  220 ,  221  and  222  are secured to the front of panel  218 . Lower section  203  includes a flat panel  223 . A bottom trim member  224  is attached to the bottom of the front of panel  223 . Vertical trim members  225 ,  226  and  227  are secured to the sides and middle of the front of panel  223 . Panels  217 ,  218  and  223  are fabricated as shown in FIGS.  6  to  8 , as flat, strong laminated structures having rigid sheet members secured to a foam plastic core.  
         [0042]    Window assembly  212 , shown in FIGS. 21 and 22 includes a rectangular frame  228  located in a rectangular opening  236  in panel  217 . Frame  228  includes a rectangular body  229  that fits in opening  236  and engages flat portions of panel  217  surrounding opening  236 . The inside end of body  229  is joined to an outwardly directed flat flange  230  located in engagement with the inside sheet member of panel  217 . Adhesives or other fasteners (not shown) secure flange  230  to panel  217 . Body  229  has an inwardly projected rib  231  having a shoulder  232 . A flat glass pane  233  engages shoulder  232 . Rib  231  has a convex outer surface to direct water and snow away from glass pane  233 . A rectangular stop member  234  telescoped into body  229  engages glass pane  233  to firmly hold pane  233  on shoulder  232 . One or more fasteners  235 , such as a screw, secure member  234  to frame  229 . Stop member  234  can be removed from frame  229  to allow a broken glass pane to be removed and replaced with a new glass pane. Other transparent sheet members, such as plastic, can be used in the window assembly in lieu of glass pane  233 . Window assembly  211  typically has the same structure as window assembly  212 .  
         [0043]    Referring to FIG. 22, panel  217  may comprise a rigid plywood inner sheet member  237  and a rigid exterior sheet member or siding  238 . Panel  217  may also include an upper border member  239  and a lower border member  240 . Sheet members  237 ,  238  and border members  239 ,  240  typically are secured to core  243  with layers of adhesive such as  241  and  242 . In this construction, panel  217  is a rigid, strong and sturdy structure that provides the support for window assemblies  211  and  212 . One advantage of the present embodiment is that sheet members  237  and  238  bonded to core  243  and border members  239  and  240  provide a panel with high strengths against bending, buckling and twisting.  
         [0044]    While there has been shown and described several embodiments of the roll-up doors of the invention, it is understood that changes and modifications in structure, material, arrangement or structures and materials may be made by those skilled in the art without departing from the invention.

Summary:
A roll-up door having one or more sections. Each section includes a foam plastic core between two opposed first and second sheet members. The first and second sheet members are generally similar in overall size, but can be fabricated from different materials. The core is housed between the sheet members and typically is fastened directly to the sheet members. The sections typically also include one or more border members around the periphery of the core. Adjacent panel sections are pivotally hinged. The border members located along the opposed mating portions of adjacent panel sections are stepped, thereby allowing the door to be raised or lowered. One or more panel sections may contain openings and securing means for one or more window assemblies.