Patent Publication Number: US-7721387-B1

Title: Track assembly for an overhead door

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of U.S. patent application Ser. No. 10/421,189 filed Apr. 22, 2003 now abandoned. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a track assembly for sectional overhead doors such as garage doors and the like. More specifically, this invention relates to such an assembly which is particularly suited for low headroom environments. 
     BACKGROUND ART 
     Overhead sectional garage doors or the like are typically provided with rollers that ride in a track system usually carried by a horizontally oriented angle member extending inwardly from the door frame. When the door is in the closed position, the rollers reside in opposed vertically oriented tracks, and when moved to an open position, the rollers travel up the vertical tracks, through opposed transitional tracks, and into opposed generally horizontally oriented tracks. 
     Traditionally, the transitional tracks are of a circular radius of curvature to make the ninety degree transition from the vertical tracks to the horizontal tracks. These transitional tracks may be a separate piece, having their ends attached to the vertical and horizontal tracks, or they may be incorporated into either the vertical tracks or the horizontal tracks thereby creating a two-piece system instead of a three piece system. In some instances, the track system may be formed as one piece incorporating the vertical tracks, the horizontal tracks and the transitional tracks. 
     The radius of the typical prior art transitional tracks generally varies between eight inches and thirty inches. Radii toward the upper end of the range are desirable because such provides for a smoother operation of the door. However, such requires more headroom. In situations where there is minimal headroom, transitional tracks with a short radius must be utilized to the sacrifice of smooth operation. 
     As a compromise, attempts have been made at providing a one piece track system which includes the vertical tracks, the horizontal tracks, and a transitional track portion having two radii of curvature. However, in order to accommodate for low headroom environments and yet still satisfactorily operate, the radii of curvature need to be quite different, that is, one of the radii needs to be substantially smaller than the other radii, and such cannot be readily accomplished in one piece. 
     Thus, the need exists for a track system which is not plagued by these problems of the prior art. 
     DISCLOSURE OF THE INVENTION 
     It is thus an object of the present invention to provide a track assembly for an overhead door which has the benefits of smooth operation while at the same time being usable in areas having low headroom. 
     It is another object of the present invention to provide a track assembly, as above, which can easily be used with a header-mounted, pivoting motorized door operator. 
     It is an additional object of the present invention to provide a track assembly, as above, which is easy to assemble and install. 
     These and other objects of the present invention, as well as the advantages thereof over existing prior art forms, which will become apparent from the description to follow, are accomplished by the improvements hereinafter described and claimed. 
     In general, a track assembly adapted to be carried by the jamb of an overhead door and made in accordance with one embodiment of the present invention includes a first track segment which has a generally straight portion and a curvilinear portion having a first radius of curvature. A second track segment includes a generally straight portion and a curvilinear portion having a second radius of curvature. The second radius of curvature is different than the first radius of curvature. The curvilinear portion of one of the segments is telescopically received within the curvilinear portion of the other of the segments to provide the only connection between the segments. A first bracket is adapted to attach the first track segment to the jamb, and a second bracket is adapted to attach the second track segment to the jamb. 
     In accordance with another aspect of the invention, a track assembly for an overhead door includes a first track segment which is generally U-shaped in profile and which includes a generally straight portion and a curvilinear portion having only a first radius of curvature. A second track segment is generally U-shaped in profile and includes a generally straight portion and a curvilinear portion having only a second radius of curvature which is larger than the first radius of curvature. Means are provided to attach the curvilinear portion of the first track segment to the curvilinear portion of the second track segment which includes an enlarged U-shaped end profile on the end of the curvilinear portion of one of the track segments to receive the end of the curvilinear portion of the other of the track segments. 
     In another aspect of the invention, the track assembly includes a first track segment which is generally U-shaped in profile and which has a generally straight portion and a curvilinear portion having only a first radius of curvature. A second track segment is generally U-shaped in profile and has a generally straight portion and curvilinear portion having only a second radius of curvature. Bracket means are attachable to the first track segment and attachable to the second track segment so as to attach the first and second track segments to each other. The end of the curvilinear portion of the first track segment has an enlarged U-shaped profile to receive the end of the curvilinear portion of the second track segment. 
     A preferred exemplary track assembly for an overhead door made in accordance with the concepts of the present invention is shown by way of example in the accompanying drawings without attempting to show all the various forms and modifications in which the invention might be embodied, the invention being measured by the appended claims and not by the details of the specification. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a fragmentary perspective view of a sectional overhead door having a track assembly made in accordance with the concepts of one embodiment the present invention. 
         FIG. 2  is an enlarged elevational view of the portion of the track assembly encircled in  FIG. 1 . 
         FIG. 3  is an exploded perspective view of the components of the track assembly shown in  FIG. 2 . 
         FIG. 4  is an exploded view of the components of a track assembly made in accordance with another embodiment of the present invention. 
         FIG. 5  is a perspective view showing the components of  FIG. 4  assembled adjacent to a door. 
     
    
    
     PREFERRED EMBODIMENTS FOR CARRYING OUT THE INVENTION 
     An overhead-type garage door is indicated generally by the numeral  10  and includes a plurality of panels  11 , each having guide rollers  12  on the lateral edges thereof. Door  10  is formed within a frame which includes vertically oriented jambs J spaced by a header H, and is suspended by a conventional counterbalance system  13  which is schematically shown in  FIG. 1 . Rollers  12  ride in a track assembly which includes opposed generally vertically positionable track segments, generally indicated by the numeral  14 , and opposed generally horizontally positionable track segments generally indicated by the numeral  15 . 
     Each vertically positionable track segment  14  includes a straight portion  16  which, when positioned for use with door  10 , is generally vertically oriented, and includes a curvilinear portion  17  at one end thereof. Both portions  16  and  17  are generally U-shaped in end profile having opposed branches  18  interconnected by a base portion  19 . As such, rollers  12  are adapted to be received between branches  18  and directed thereby as they move along track segment  14 . 
     Similarly, each horizontally positionable track segment  15  includes a straight portion  20  which, when positioned for use with door  10 , is generally horizontally oriented, and includes a curvilinear portion  21  at one end thereof. Both portions  20  and  21  are generally U-shaped in end profile having opposed branches  22  interconnected by a base portion  23 . As such, rollers  12  are adapted to be received between branches  22  and directed thereby as they move along track segment  15 . 
     It has been found that the radius of curvature of curvilinear portion  17  can be in the range of approximately four to eight inches. A radius of curvature of about four inches extending over approximately sixty-eight degrees is preferred. The radius of curvature of curvilinear portion  21  can be in the range of fifty to eighty inches depending on the height of the panels  11  which make up door  10 . A radius of curvature of about seventy-one inches extending over approximately twenty-two degrees is preferred. Thus, the ratios of the radius of portion  21  to the radius of portion  17  could be in the range of approximately twenty-to-one to approximately six-to-one. The combination of these radii provide for smooth operation while at the same time rendering the door  10  useable in areas of low headroom. 
     Curvilinear portion  17  is attached to curvilinear portion  21  by means of a flag angle or bracket generally indicated by the numeral  30 . As shown in  FIGS. 2 and 3 , bracket  30  is generally L-shaped in configuration having a generally vertically oriented structural mounting face  31  and a generally horizontally oriented track engaging face  32 . An offset rib  33  runs down mounting face  31  and extends into track engaging face  32 , and a second offset rib  34  runs along the junction of faces  31  and  32 . Together, ribs  33  and  34  add strength to bracket  30 . 
     Mounting face  31  includes an aperture  35  to facilitate attachment to a portion of counterbalance system  13 , and the top of face  31  is provided with a notch  36  to permit the passage of counterbalance system  13  therethrough. As shown in  FIG. 3 , face  31  is also provided with a mounting flange  37  having a plurality (one shown) of apertures  38  therein to facilitate attachment of bracket  30  to the header H or a jamb J of the frame around door  10 . Flange  37  is integrally formed with a flange  39  on track engaging face  32  to further strengthen bracket  30 . 
     Track engaging face  32  of bracket  30  is provided with a pair of tabs  40  spaced from face  32  and oriented 180° of each other. Face  32  is also provided with a lock lug  41  which is also spaced from face  32 . The base portion  19  of track portion  17  is provided with a slot aperture  42  which is generally circular in shape with its circumference being interrupted by a pair of diametrically opposed semicircles  43 . The base portion  23  of track portion  21  is provided with a tapered, generally tear drop-shaped, slot  44  having an end  45  with a narrow opening and an end  46  with an opening wider than the opening at end  45 . The larger end  46  is positioned to be adjacent to the end of track portion  21 . 
     In order to attach curvilinear portion  17  of track segment  14  to curvilinear portion  21  of track segment  15 , and thereby install the track assembly for use with door  10 , tabs  40  of bracket  30  are aligned with opposed semicircles  43  of slot aperture  42  and then pushed therethrough. Then, bracket  30  and track segment  14  can be rotated ninety degrees relative to each other so that bracket  30  is engaging track segment  14  as shown in  FIG. 2 . Thereafter, in order to attach curvilinear portion  21  to bracket  30  and to curvilinear portion  17  to track segment  14 , the end of curvilinear portion  21  can be slid into, or otherwise telescoped into, the end of curvilinear portion  17 . For this purpose, the U-shaped profile of portion  17  is enlarged near the end of portion  17 , as at  47 , to receive the end of portion  21 . As such, there is a smooth roller transition between portions  17  and  21  so that there is no undue noise and so that there is otherwise no bumpy transition of rollers  12  as they pass between track segment  14  and track segment  15 . At the same time that track portion  21  is slid into track portion  17 , lug  41  of bracket  30  is received through the large end  46  of slot  44 . When portion  21  is fully seated in portion  17 , lug  41  will be positioned in the smaller end  45  of slot  44  such that bracket  30  is then holding track portion  21 . 
     At this point, bracket  30  may be attached to the door frame while carrying and attaching one end of track segments  14  and  15 , and the other ends of track segments  14  and  15  may be conventionally attached to the frame and surrounding structure so that track portion  21  cannot be slid out of track portion  17  and otherwise released from bracket  30 . 
     It should be appreciated that a track assembly constructed in accordance with this embodiment and installed as described herein does not require the conventional horizontally extending support angle at the area of the transition of the track from vertical to horizontal because the long curvilinear portion  21  effectively acts to provide such support. In addition, this track assembly enables one to use a header mounted pivotal door operator without requiring additional components to account for the lack of headroom as was required in the prior art. That is, when door  10  is moving through the track assembly of the present invention, door  10  begins to move back almost immediately on track segment  15  which allows one to use a pivotal door operator which is desirable to lock the door in the down position. 
     A track assembly made in accordance with another embodiment of the invention is indicated generally by the numeral  50  and is shown in  FIGS. 4 and 5 . Track assembly  50  includes a vertically positionable track segment  14  and a horizontally positionable track segment  15  which, except as will hereinafter be discussed, are basically identical to that shown in  FIGS. 1-3  and previously described. Thus, identical components shown in  FIGS. 4 and 5  have been given the same reference numerals as that shown in  FIGS. 1-3 , and the description thereof will not be repeated with reference to  FIGS. 4 and 5 . 
     In addition to track segments  14  and  15 , track assembly  50  includes a bracket, or what is known in the art as a flag angle, generally indicated by the numeral  51 , and another angle bracket generally indicated by the numeral  52 . Flag angle  51  is a conventional bracket having several features which render it usable in many types of track assemblies. When used in track assembly  50 , face  53  of bracket  51  is provided with a plurality of apertures  54 , selected of which receive fasteners  55  ( FIG. 5 ) to attach bracket  51  to jamb J. A second face  56  of bracket  51  is provided with a plurality of vertical slot apertures  57  to receive one or more fasteners  58  with a nut  59  to attach bracket  52  to bracket  51  in a manner to be hereinafter described. Bracket  51  is also provided with a flag or tab  60  having slot apertures  61  formed therein. Tab  60  is attached to track segment  15  by fasteners  62  which pass through holes  63  in track segment  15 , and through slot apertures  61  to be held by nuts  64 . 
     Angle bracket  52  includes angled faces  65  and  66  and is also a conventional item having several features which render it usable in many types of track assemblies. When used in track assembly  50 , a slot aperture  67  in face  65  is used to receive bolt  58  as previously described to attach bracket  52  to bracket  51  and thereby to jamb J as well. Face  65  also includes longitudinally spaced apertures  68  which are adapted to receive fasteners (not shown) to attach bracket  52  to track segment  15 . To that end, track segment  15  is provided with spaced key-hole slots  69  which are alignable with apertures  68  to receive the fasteners. If necessary, bracket  52  may also be provided with an aperture  70  adjacent to at least one of the apertures  68  which may be aligned with an aperture  71  in track segment  15  and receive a fastener (not shown) to maintain the other fasteners in slots  69 . 
     Thus, flag angle bracket  51 , which is attached to jamb J, carries the vertical track segment  14  and the angle bracket  52  which, in turn, carries the horizontal track segment  15 . The curvilinear portion  21  of track segment  15  telescopes within enlarged end  47  of curvilinear portion  17  of track segment  14 , which is advantageously the only connection between track segments  14  and  15 . 
     To assemble track assembly  50 , flag angle bracket  51  is preferably first attached to jamb J and to track segment  14 , and angle bracket  52  is attached to track segment  15  as previously described. The end of track segment  15  can then be telescoped into the end of track segment  14 , and angle bracket  52  may then be attached to flag angle bracket  51  as previously described. 
     As such, the track assemblies described herein substantially improve the art and otherwise accomplish the objects of the present invention.