Patent Publication Number: US-6655442-B2

Title: Sectional door with extruded panel members

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The subject invention generally pertains to sectional doors and more specifically to door panel with extruded panel members. 
     2. Description of Related Art 
     A sectional door typically includes a series of panels whose adjacent horizontal edges are each pivotally connected by a row of hinges. As the door opens or closes, the door panels travel along two lateral tracks that in one configuration curve between horizontal and vertical. To close the door, the tracks guide the panels to a vertical position. When the door opens, the hinges allow the panels to curve around onto horizontal sections of the tracks, where the door panels store horizontally overhead. In other configurations, the sectional door maintains a generally vertical, planar configuration and is stored more directly above the doorway. Such doors, regardless of their configuration, can be powered up or down or can be manually operated. To ease the operation of the door, a torsion spring is often used to offset the weight of the door panels. Sectional doors are commonly used as residential garage doors; however, they are also often used in warehouses and other industrial buildings. 
     When used in high-traffic industrial applications, sectional doors are very susceptible to being struck by large trucks, trailers, forklifts and other vehicles passing through the doorway. Collisions are often caused by a door&#39;s torsion spring becoming weak with age or not being properly preloaded, which can allow a door to droop into the doorway by not opening fully. Consequently, an upper edge of a vehicle may catch the lowest panel of the door, which often breaks or destroys just that panel. 
     To avoid having to repeatedly replace the lowest panel with an identical one, a more impact-resistant panel can be used as a replacement, such as a panel that is tougher and more flexible. However, to do so, the replacement panel should be about the same size as the one being replaced. The replacement panel should also have a seal member whose shape and location is suitable for sealing against an existing door panel. Providing such a replacement door panel can be difficult to do, because of the different types of seals and the wide range of existing door panel sizes. A panel design whose length, width or seal configuration is not readily altered would generally require a large inventory of panels to meet the requirements of numerous door applications. 
     Some door panels have metal frames with sheet metal skins. Such construction features can make a door panel difficult to shorten or lengthen (along the width of the doorway) to match the existing panels. Such features also make it difficult to change a door panel&#39;s width (vertical dimension when the door is closed). 
     Other door panels may perhaps be extruded, such as those of U.S. Pat. Nos. 5,718,276; 5,445,206; 5,170,832; 4,979,553; 4,924,932; 4,432,591 and 3,247,637. Extruded panels may be relatively easy to cut to length (i.e., doorway width); however, their width and seal geometry is generally fixed. It&#39;s conceivable that interconnecting a series of relatively narrow panels could create doors having various accumulated heights. However, with current designs, flexing between each adjacent panel means each individual panel may need to have its own means for guiding itself along the track. Since each additional guide member contributes drag to the door&#39;s movement, a door with numerous narrow panels may be more difficult to open and close than a door with fewer panels. The problem of drag not only applies to doors whose bottom panel is replaced, but also applies to new door construction. 
     Consequently, there is a need to be able to manufacture replacement door panels as well as entire doors for doorways of various width and height, and to be able to do so without having to manufacture and stock numerous door panels of various sizes and seal geometries. 
     SUMMARY OF THE INVENTION 
     In some embodiments, a sectional door is provided with several panel members with at least one panel member having more freedom to pivot relative to a first adjacent panel or panel member than it is able to pivot relative to a second adjacent panel member. 
     In some embodiments, one panel member is substantially fixed to a first adjacent panel member, but is able to pivot relative to a second adjacent panel or panel member. 
     In some embodiments, a door panel comprises a series of extruded panel members. 
     In some embodiments, a sectional door is provided with a door panel comprising several panel members of various widths. 
     In some embodiments, a door panel is comprised of several interlocking panel members. 
     In some embodiments, a door panel member is provided with a hollow interior, so the panel can be readily extruded. 
     In some embodiments, a door panel member is provided with a hollow interior, so the panel can be filled with thermal insulation. 
     In some embodiments, a seal member can be attached to a door panel member at alternate locations, so the resulting panel can serve as a replacement panel for existing doors of various seal designs. 
     In some embodiments, a door panel comprises a set of interlocking panel members that are reinforced by two end caps, wherein the end caps facilitate the mounting of various door hardware. 
     In some embodiments, a door panel is made of door panel members of plastic for flexibility and includes a hinge made of steel for strength. 
     In some embodiments, a sectional door includes a door panel of a transparency ranging from transparent to opaque. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of one embodiment of an overhead-storing sectional door in a partially open position, with the door being viewed from inside a building and looking out. 
     FIG. 2 is a cross-sectional view taken along line  2 — 2  of FIG.  1 . 
     FIG. 3 is a top view of a door panel of in FIG.  1 . 
     FIG. 4 is a cross-sectional end view in an exploded arrangement showing various parts of a door panel used in the door of FIG.  1 . 
     FIG. 5 is a cross-sectional end view of the door panel of FIG. 4, but shown assembled and connected to an adjacent door panel having a tongue and groove seal design. 
     FIG. 6 is a cross-sectional end view similar to FIG. 5, but showing a door panel of a different assembled width and with the door panel connected to an adjacent door panel having a shiplap seal design. 
     FIG. 7 is a cross-sectional end view of an alternate embodiment of two adjoining panel members. 
     FIG. 8 is similar to FIG. 7, but showing yet another embodiment of two adjoining panel members. 
     FIG. 9 is similar to FIG. 1, but showing another embodiment of a door panel. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A sectional door  10 , shown partially open in FIGS. 1 and 2, includes a series of door panels  12 ,  14 ,  16  and  18  that are interconnected along their adjacent horizontal edges by hinges  20 . In this description, the term, “panel” describes one of typically four or five sectional door components, each of which is generally planar and hingedly interconnected to panels above and below, except for the top and bottom panels. As door  10  opens or closes relative to a doorway  22 , guide members, such as rollers  24 , guide the movement of the panels along two lateral tracks  26  and  28 . In this example, tracks  26  and  28  curve between horizontal and vertical; however, it is well within the scope of the invention to have tracks  26  and  28  run generally linearly or only curve slightly, so that when the door opens, the door panels move above doorway  22 , but remain in a generally vertical or slightly angled orientation. To close door  10 , the vertical sections of tracks  26  and  28  guide the panels to a vertical position across doorway  22 , as indicated by the positions of panels  12  and  14 . When door  10  opens, hinges  20  allow the panels to curve around onto the horizontal sections of tracks  26  and  28 , where the door panels store horizontally overhead, as indicated by the position of panel  18 . 
     The actual structure of panels  12 ,  14 ,  16  and  18  can vary from one door to another, vary among panels of the same door, or be the same for each panel of the same door and still remain well within the scope of the invention. However, many of the door panel embodiments are especially useful in retrofit applications where a new panel replaces the lowest panel of a door whose original panels are not as impact resistant as the new one. So, a preferred embodiment will be described with reference to door  10  whose lowest panel  12  comprises a set of interconnected panel members  30 ,  32  and  34  that are relatively tough and impact resistant. 
     Panel members  30 ,  32  and  34  can be extruded of PVC in different shapes and sizes, as shown generally in FIGS. 4-6. The panel members can be cut to a particular length  36  that is appropriate for a width  38  of doorway  22  (see FIG.  1 ), or two or more panel members can be laid end-to-end to create any desired length for other doorways (e.g., see panels  84  and  86  of FIG.  9 ). A thickness  39  of each of the panel members is generally the same; however, the exposed width of a panel member can vary from one panel member to the next. When referring to a panel member, the term “width” refers to a dimension of the panel member measured along a direction generally parallel to the direction the panel member translates as the door opens or closes. For example, when the door is closed with a panel member lying generally along a vertical plane, the width of the panel member is measured vertically. For door panel  12 , the width of panel members  30 ,  32  and  34  is approximately 6 inches, 3 inches, and 1 inch, as indicated by dimensions  40 ,  42  and  44 , respectively (see FIG.  4 ). This allows the panel members to be interconnected in various combinations to create door panels of various total widths. In FIG. 5, for example, panel members  30 ,  32  and  34  provide door panel  12  with a total width of about 22 inches (1+3+6+6+6). In FIG. 6, panel members  30  and  34  provide a door panel  12 ′ whose total width is 19 inches (1+6+6+6). 
     To interconnect the panel members, each panel member  30 ,  32  and  34  includes a T-slot  46  adapted to receive a mating protrusion  48  of an adjacent panel member by sliding protrusion  48  lengthwise into slot  46 . T-slot  46  and protrusion  48  can be extruded along with the rest of the panel member to comprise a unitary piece. In some cases, sheet metal end caps  50  (see FIG. 3) can be fastened to each end of door panel  12  to provide panel  12  with greater rigidity and provide a strong surface to which rollers  24  and metal hinges  20  can be attached. Although, T-shaped slots and protrusions are preferred, because they provide the panel members with an interlocking connection  52 , other panel-to-panel interfaces are also well within the scope of the invention. For example, in some embodiments, a tongue and groove connection  58  provides an interface between adjacent panels  54  and  56 , as shown in FIG.  7 . In another embodiment, a butt connection  64  provides an interface between panels  60  and  62 , as shown in FIG.  8 . With connections  58  and  64 , however, additional hardware, such as end caps  50 , would be needed to hold the panels together. It should be noted that the top surface of panel member  34  may be generally flat to facilitate a pivotal connection to the adjacent panel  14  or  14 ′. 
     Panel members  30  and  32  can have a hollow interior  66  and  68 , as shown in FIG. 5, or its interior can be filled with a thermal insulating filler material  70 , such as foam, as shown in FIG.  6 . Other portions of members  30 ,  32  and  34  are also hollow to provide a panel member with a relatively thin and substantially uniform material thickness  72 . This not only reduces the amount of material required to make a panel member, but also facilitates the use of a conventional plastic extrusion process, wherein softened extruded material is able to solidify at a quick, uniform rate. 
     To enable door panel  12  to seal against various adjoining panels, such as panel  14  of FIG. 5 or panel  14 ′ of FIG. 6, panel member  12  includes several slots  74 ,  76  and  78  into which a compliant vinyl seal member  80  can be selectively installed to suit the geometry of the adjoining panel. Seal member  80  installed in slot  76  fits the tongue and groove seal geometry of panel  14 , and seal member  80  installed in slot  78  accommodates the shiplap seal design of panel  14 ′. 
     In some cases, a door panel may include one or more panel members with different levels of transparency. In FIG. 9, for example, a door  10 ″ includes a door panel  12 ″ comprising opaque panel members  82  and  84 , transparent panel members  86  and  88 , and a translucent panel member  90 . Transparent panels  86  and  88  serve as windows, and translucent panel  90  allows some light to pass, but provides more privacy than what is provided by panels  86  and  88 . For door  10 ″, panels  14 ″,  16 ″ and  18 ″ are of a construction similar to that of panel  12  of door  10 . 
     The door panel thus described, formed from interconnected door panel members, may advantageously be used as a replacement panel for the bottom panel of a sectional door. At the same time, the resulting door panel may be used to replace any other door panel. Finally, the entire door may be formed of such panels. 
     Although the invention is described with reference to a preferred embodiment, it should be appreciated by those skilled in the art that various modifications are well within the scope of the invention. Therefore, the scope of the invention is to be determined by reference to the claims that follow.