Abstract:
The present invention is an L-bracket formed, shaped and threaded to become a suspended ceiling anchor capable of engaging multiple diameters of threaded hanging rods, providing spacing means between threaded sections for a user to avoid threading the end of a threaded hanging rod up to two thirds of the end threads of the threaded hanging rod, thereby reducing installation time and complexity.

Description:
FIELD OF THE INVENTION 
     The present invention is broadly directed to installation of internal hanging ceilings and more particularly to an improved anchor device affixed at a desired position to a solid portion of said ceiling for connecting a threaded hanger from which said internal hanging ceiling will be suspended. 
     BACKGROUND OF THE INVENTION 
     In construction of commercial offices, immediately visible ceilings are often comprised of lightweight fiber panels supported from a horizontal framework of aluminum struts and T- or L-cross section pieces, which also generally will include recessed lighting fixtures. The visible portion of the internal ceiling is actually supported from a horizontal structure above it, which horizontal structure has sufficient structural strength to prevent the suspended ceiling from falling into the room space below. Said horizontal structure may be formed of metal beams or plates, wood beams or sheets, concrete, or similar structural materials. 
     It is well known that installation of suspended ceilings is generally accomplished by way of first setting anchors into the horizontal structure by workers standing at floor level, which is often a distance of five or more feet from a worker&#39;s elevated arms. Because of the number of anchors required for installation of suspended ceilings from the horizontal structure, it is not efficient for workers to use a ladder to set said anchors. Instead, it is common practice for workers to use a special tool with an explosive charge device and anchoring shaft at the end of a pole to work from ground level to fix said anchors to the horizontal structure, as shown and described in U.S. Pat. No. 5,544,800, which incorporated by reference herein. 
     U.S. Pat. No. 4,979,715 discloses the simplest anchor and twisted hanger assembly, one which uses a screw as an anchor that must be directly screwed into a horizontal structure. U.S. Pat. No. 8,602,365 discloses a method of attaching a threaded positioner on a hanging threaded rod. U.S. Pat. No. 5,667,181 discloses an anchor with a nut with a single diameter, but which can be replaced with a nut of a different diameter. U.S. Pat. No. 3,266,202 discloses an anchor using a triangular flange but introducing an efficient means for forming a threaded section in the anchor, i.e., stamping lateral semi-circular sections in adjacent and opposite directions, within which concave portions are formed threads. U.S. Pat. No. 2,725,127 discloses an anchor that is capable of supporting a threaded hanging rod of a single diameter. 
     Some of the problems hanger assemblies of anchors and their threaded hanging rod have been their cost, multiple parts, and difficulty of installation. Such hanger assemblies have a minimum of three parts and may have five or more, depending on whether a separate fixing device or washer is employed. Since the installation is usually done on a scaffold or step ladder, loose parts can be a problem. Even if all of the parts as a set are packaged, the opening of the package and assembly of the parts can be a problem. If one of the parts drops or rolls away, the installer has to climb down to retrieve the part, if it can be found, or get another package. Multiple part fasteners always take more time to install, and are more costly, especially if packaged. 
     Structural and weight requirements of a specific area of a suspended ceiling are often not known beforehand. It is well known that later modifications to a planned installation of a suspended ceiling may require a change in diameter of threaded hanging rods than those installed in said anchors, requiring either installation of adjacent anchors capable of receiving greater diameter threaded hanging rods or manually changing nuts by tedious ladder supported work as in the &#39;181 patent. 
     There is a need for an anchor for suspended ceilings which is inexpensive, lightweight, and can accommodate more than one diameter of threaded hanging rods. 
     SUMMARY OF THE INVENTION 
     The present invention is an L-bracket formed, shaped and threaded to become a suspended ceiling anchor capable of engaging multiple diameters of threaded hanging rods, providing spacing means between threaded sections for a user to avoid threading the end of a threaded hanging rod up to two thirds of the end threads of the threaded hanging rod, thereby reducing installation time and complexity. 
     The present invention has improved on the stamped, threaded, and semi-circular sections of the &#39;202 patent. The present inventor has found that all structural requirements for suspended ceilings, even for engineering in earthquake prone areas, are met with providing only three semi-circular sections (instead of four as taught in the &#39;202 patent), reducing installation time and requirements. Further, by providing non-threaded spaces between the semi-circular sections, the present invention allows a user to avoid up to two thirds or more of the threading work that prior art anchors as shown in the &#39;202 patent. 
     The present invention provides two or more vertically adjacent rod areas, each comprising three semi-circular sections, where each vertically inferior rod area comprises an effective threaded diameter substantially greater than a rod area above it. Thus, a user installing a smaller diameter threaded hanging rod will insert it into and bypass the threads of the lowest rod area of the invention device until the smaller diameter threaded hanging rod engages an effective threaded diameter of a higher rod area that results in threaded engagement of the smaller diameter threaded hanging rod with the semicircular sections of the higher rod area. 
     Various objects and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings submitted herewith constitute a part of this specification, include exemplary embodiments of the present invention, and illustrate various objects and features thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side perspective view of the invention anchor, showing means for receiving threaded hanging rods of multiple diameters. 
         FIG. 2  is front view of  FIG. 1 . 
         FIG. 3  is a rear view of  FIG. 1 . 
         FIG. 4  is a bottom view of  FIG. 1 . 
         FIG. 5  is a side view of  FIG. 1 . 
         FIG. 6  is cutaway view of  FIG. 5 . 
         FIG. 7  is the anchor of  FIG. 6  showing an angled insertion of a largest diameter threaded hanging rod into the invention hanger without need for threading for up to two thirds of the engaging threads. 
         FIG. 8  is the assembly of  FIG. 7  showing the largest diameter threaded hanging rod in a fully threaded engagement with the invention hanger. 
         FIG. 9  is the anchor of  FIG. 6  showing an angled insertion of a smaller diameter threaded hanging rod into the invention hanger without need for threading up to two thirds of the engaging threads. 
         FIG. 10  is the assembly of  FIG. 9  showing the smaller diameter threaded hanging rod in a fully threaded engagement with the invention hanger. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
     Referring to the drawings in more detail,  FIG. 1  is a side perspective view of the invention anchor  10  is generally an L-shaped bracket, showing means for receiving threaded hanging rods of multiple diameters along direction  10   a . Plate  11  comprises a punched down conical receiver  24  defining opening  24   a , which is adapted to receive a nail, screw, bolt or the like from below and which then is driven into the horizontal structure to affix anchor  10  into the horizontal structure. 
     By way of such affixation of plate  11  to the horizontal structure, plate  12  is suspended vertically downward, causing direction  10   a  to also be aligned vertically as well. A central portion of plate  12  from elevation  13  to end  14  comprises two rod areas in which two or more vertically adjacent rod areas (larger diameter and lower rod area  22  is shown), each comprising three semi-circular sections (sections  15 ,  16  and  17  in lower rod area  22 ) (sections  18 ,  19  and  20  in an upper rod area), where each vertically inferior rod area  22  comprises an effective threaded diameter substantially greater than the upper rod area above it. Thus, a user installing a smaller diameter threaded hanging rod will insert it into and bypass the threads of the lowest rod area  22  of the invention device until the smaller diameter threaded hanging rod engages an effective threaded diameter of an upper rod area that results in threaded engagement of the smaller diameter threaded hanging rod with the semicircular sections of the higher rod area. 
     It is critical to the operation of the invention anchor  10  that non-threaded sections  21   b  through  21   f  be provided between the separated threaded sections  15  through  20  respectively. A non-threaded section  21   a  is optional for the invention. Non-threaded sections  21   b  through  21   f  allow easy insertion of a threaded hanging rod as described below. Further, it is critical to the formation of sections  15  through  20  that non-threaded sections  21   a  through  21   f  be formed before forming of sections  15  through  20 . The threaded sections shown in the &#39;202 patent cannot be formed by stamping—the stamping process would mis-form the semi-circular sections, making them un-usable for later machining of threads and threaded connection to a threaded hanging rod. Those threaded sections of the &#39;202 patent must be formed in some other machining method other than stamping. 
     Formation of the sections  15  through  20  in the central portion of plate  12  is important to the invention concept, in that no separate pieces are required for this invention anchor than the piece shown in  FIG. 1  (excepting some means for fixing anchor  10  to a horizontal structure). In a first step, plate  12  is flat and has no openings or indentations. In a second step, slots are cut which ultimately become non-threaded sections  21   a  through  21   f  defined in plate  12 . In a third step, a convex stamp first stamps the concave semi-circular shapes of sections  15 ,  17 ,  18  and  20 . In a fourth step, plate  12  is flipped over and a convex stamp first stamps the concave semi-circular shapes of sections  16  and  19 . In a fifth step, threads are cut in sections  18 ,  19 , and  20 . In a sixth step, threads are cut in sections  15 ,  16  an  17 . 
     One skilled in the art will appreciate from the disclosure of the figures and this description that each section of lower rod area  22  or the upper rod area are adapted to engage only one side of a threaded hanging rod, but that forming vertically adjacent threaded sections of the rod areas on opposite sides of the flat portion of plate  12  results in a structure which provides substantially the same resistance to vertical downward for on an engaged threaded hanging rod as a fully cylindrical threaded bore or at least dramatically more such support than the short threaded sections shown in the &#39;127 or &#39;181 patents could possible provide. 
       FIG. 2  is front view of the anchor  10   FIG. 1 .  FIG. 3  is a rear view of the anchor  10   FIG. 1 .  FIG. 4  is a bottom view of the anchor  10   FIG. 1 , showing a much smaller threaded diameter of section  18  than that of section  15 .  FIG. 5  is a side view of the anchor  10   FIG. 1 .  FIG. 6  is cutaway view of the anchor  10   FIG. 5 , showing a punched down space  24   b  and opening  24   a , whereby space  24   b  results from a stamping operation of a flat plate  11  to accommodate fixing means driven with sufficient force to deform receiver  24  upward. 
       FIG. 7  is the anchor of  FIG. 6  showing an angled insertion along paths  26  and  27  of a largest diameter threaded hanging rod  25  past the threads of sections  15  and  16  into the invention hanger  10  without need for threading for up to two thirds or more of the engaging threads in sections  15  and  16 . 
       FIG. 8  is the assembly of  FIG. 7  and the largest diameter threaded hanging rod  25  in a fully threaded engagement with the invention hanger after having been rotated in direction  31 . 
       FIG. 9  is the anchor of  FIG. 6  showing an insertion of a smaller diameter threaded hanging rod  28  into the invention hanger anchor  10  without need for threading up to two thirds of the engaging threads (those of sections  18  and  19 ) by moving rod  28  first past the larger diameter of the lower rod area and moving rod  28  in direction  29  so that, similar to the actions shown in  FIGS. 7 and 8 , smaller diameter threaded hanging rod  28  moves past the threads of sections  18  and  19  into the invention hanger  10  without need for threading for up to two thirds or more of the engaging threads in sections  17  and  18 . 
       FIG. 10  is the assembly of  FIG. 9  showing the smaller diameter threaded hanging rod  28  in a fully threaded engagement with the invention anchor  10  at sections  18 ,  19  and  20 . 
     In a specific example, the upper rod area comprises effective diameter and threads of ¼″-20UNC and the lower rod area of ⅜″-16UNC. Preferably, the difference in effective diameters of the upper rod area and the lower rod area is one fourth inch or less, one eighth inch or less, or one sixteenth inch. In a preferred embodiment, a vertical length of the sections is 12 millimeters or less, 10 millimeters or less, or from 6 to 8 millimeters. Preferably, vertical distance of non-threaded sections is 5 millimeters or less, 4 millimeters or less, or 2 millimeters or more. 
     It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown.