Abstract:
A hanger assembly including an adjustable bar and a fixture box for rapidly installing and centering an electrical fixture over a hole in a ceiling. The adjustable bar includes an elongated tubular member, a threaded rod rotatably connected to the tubular member, joist engaging members on each end of the bar, and a fastening arrangement for securing the fixture box with respect to the adjustable bar. The adjustable bar can be adjusted to a shortened configuration to allow easy passage through a hole in a ceiling and the tubular member then rotated to force the joist engaging members into secure contact with the joists. The fastening arrangement permits loosening and readjustment of the hanger assembly to enable centering the fixture box above the hole.

Description:
FIELD OF THE INVENTION 
   This invention relates to hangers for electrical fixtures and specifically to a hanger assembly including a fixture box that may be inserted through a hole in a ceiling to secure an electrical fixture to overhead joists and that further permits adjustments in the positioning of the fixture box to insure that it is centered above the hole. 
   BACKGROUND OF THE INVENTION 
   Electrical fixtures such as fans and lights are commonly suspended from overhead joists of buildings to provide air circulation, lighting, and similar services. 
   Many devices have been proposed for the suspension of electrical fixtures from ceilings. U.S. Pat. No. 4,463,923 to Reiker, for example, discloses a hanger assembly for installation from beneath a ceiling through a junction box aperture in the ceiling without complete prior removal of a previously installed light-weight hanger assembly. The hanger assembly includes an elongated linearly expanding brace means connected between two joist engaging means for expanding from a short to a longer length to bring each of the joist engaging means into pressure contact with the joists. Reiker&#39;s hanger assembly includes a junction box that is rigidly connected to the brace means for rigidly connecting the junction box with the brace assembly. 
   Although the hanger assembly of Reiker will adequately support an electrical fixture from overhead joists, there is no easy means for centering the junction box over the hole in the ceiling through which the hanger assembly has been installed. Readjusting the position of the junction box on Reiker&#39;s hanger assembly requires (see FIG. 3) several steps, including 1) removal of two screws (86), 2) removal of the lower box portion (88) from the upper box portion (74), 3) removal of a locking nut (82). 4) removal of the upper box portion (74), and then 5) loosening of two screws (66) which connect the lower bracket (64) to the upper bracket (62) and to the brace (42). After the screws (66) are loosened, the brackets could be slid along the brace to the correct position. However, as the junction box has been disassembled at this point and is not mounted on the brace, the installer would not be able to align the junction box with the hole in the ceiling, but would rather have to estimate the junction box&#39;s final position based upon the position of the brackets. The junction box would then need to be reattached to the brace, which would require the reversal of the above enumerated steps. 
   Accordingly, what is needed is a hanger assembly including a junction box that may be inserted through a hole in a ceiling to secure an electrical fixture to overhead joists and that further permits an easy adjustment of the positioning of the junction box to insure that it is centered above the hole. 
   SUMMARY OF THE INVENTION 
   The invention is a hanger assembly including an adjustable bar and a fixture box assembly for rapidly installing and centering an electrical fixture over a hole in a ceiling. The adjustable bar, which includes an elongated tubular member and a threaded rod rotatably connected thereto, can be adjusted to a shortened configuration to allow easy passage through the hole in the ceiling. The adjustable bar has joist engaging members on each end including a first joist engaging member rotatably attached to the tubular member and a second joist engaging member rigidly attached to the threaded rod. A fixture box assembly is secured to the tubular member. A pair of downward depending legs is rigidly secured to each of the joist engaging members. After being placed through the hole in the ceiling with the downward depending legs resting on the upper surface of the ceiling, the tubular member can be rotated to force the joist engaging members into secure contact with the joists. The fixture box assembly can then be easily centered above the hole by loosening of a fastening arrangement that is easily accessible from below. Retightening of the fastening arrangement secures the fixture box assembly to the tubular member and renders it ready to accept an electrical fixture thereto. 
   OBJECTS AND ADVANTAGES 
   The hanger assembly of the present invention exhibits several advantages over the prior art including:
         a) A fixture box assembly that can be easily accessed from below and simply adjusted in position longitudinally along the tubular member without having to remove the fixture box assembly from the hanger assembly.   b) A fastening arrangement that may be loosened and then reconnected without causing misalignment of the fixture box assembly with respect to the tubular member.   c) A fixture box assembly that can be easily adjusted to a plurality of positions along the tubular member.   d) All the fasteners required to complete the installation of a fixture box from overhead joists are included with the hanger assembly.       

   These and other objects and advantages of the present invention will be better understood by reading the following description along with reference to the drawings. 

   
     DESCRIPTION OF THE DRAWINGS 
       FIG. 1  has been amended to add reference numeral  28 , which was referred to in the specification but mistakenly omitted in the original figure. 
       FIG. 2  is a bottom view of the hanger assembly of  FIG. 1 . 
       FIG. 3  is a is a side view of the hanger assembly of  FIG. 1   
       FIG. 4  is an end view of a first end of the hanger assembly taken along line  4 - 4  of  FIG. 3 . 
       FIG. 5  is a side view of the first end of the hanger assembly taken along line  5 - 5  of  FIG. 2 . 
       FIG. 6  is an end view of a second end of the hanger assembly taken along line  6 - 6  of  FIG. 3 . 
       FIG. 7  is a side view of the second end of the hanger assembly taken along line  7 - 7  of  FIG. 2 . 
       FIG. 8  is a plan view of an electrical fixture box, which forms a portion of the hanger assembly of  FIG. 1 . 
       FIG. 9  is a side view of the fixture box taken along line  9 - 9  of  FIG. 8 . 
       FIG. 10  is a side view of the fixture box taken along line  10 - 10  of  FIG. 8 . 
       FIG. 11  is a sectional view of the fixture box taken along line  11 - 11  of  FIG. 8 . 
       FIG. 12  has been amended to add reference numeral  52 , which was referred to in the specification but mistakenly omitted in the original figure. 
       FIG. 13  is a plan view of a top mounting plate portion of the hanger assembly of  FIG. 1 . 
       FIG. 13A  is a side view of the top mounting plate taken along line  13 A- 13 A of  FIG. 13 . 
       FIG. 13B  is a plan view of a top mounting plate taken along line  13 B- 13 B of  FIG. 13 . 
       FIG. 14  has been amended to add reference numerals  34 ,  36 ,  38 ,  68 ,  72 ,  76 , and  80 , which were referred to in the specification but mistakenly omitted in the original figure. 
   

   TABLE OF NOMENCLATURE 
   The following is a listing of part numbers used in the drawings along with a brief description: 
   
     
       
             
             
           
             
             
           
         
             
                 
             
             
               Part Number 
               Description 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
               20 
               hanger assembly 
             
             
               22 
               tubular member 
             
             
               24 
               first end of tubular member 
             
             
               26 
               second end of tubular member 
             
             
               28 
               central bore of tubular member 
             
             
               30 
               threaded bore portion 
             
             
               32 
               threaded rod 
             
             
               34 
               first joist engaging member 
             
             
               36 
               second joist engaging member 
             
             
               38 
               fixture box assembly 
             
             
               40 
               fixture box 
             
             
               42 
               lower edge of fixture box 
             
             
               44 
               pair of downward depending legs 
             
             
               45 
               two-piece bracket arrangement 
             
             
               46 
               top mounting plate 
             
             
               48 
               lower mounting plate 
             
             
               50 
               screw 
             
             
               52 
               top of fixture box 
             
             
               53 
               fastening arrangement 
             
             
               54 
               fastener 
             
             
               56 
               threaded bores in top mounting plate 
             
             
               58 
               opposing corners of top mounting plate 
             
             
               60 
               second plane 
             
             
               62 
               lower surface of downward depending leg 
             
             
               64 
               first plane 
             
             
               66 
               ceiling covering 
             
             
               68 
               outwardly extending spike 
             
             
               70 
               top portion of electrical fixture 
             
             
               72 
               joist 
             
             
               74 
               hole 
             
             
               76 
               first overhead joist 
             
             
               78 
               top surface of ceiling covering 
             
             
               80 
               second overhead joist 
             
             
               82 
               top wall of fixture box 
             
             
               84 
               sidewall of fixture box 
             
             
               86 
               corners of fixture box 
             
             
               88 
               inner cavity 
             
             
               90 
               bent over tab 
             
             
               91 
               opening in sidewall of fixture box 
             
             
               92 
               lug 
             
             
               94 
               rivet 
             
             
               96 
               large diameter knockout 
             
             
               100 
               temporary storage receptacle 
             
             
               102 
               fixture fastener 
             
             
               104 
               permanent receptacle 
             
             
               106 
               C-shaped fitting 
             
             
               108 
               large apertures in top wall of fixture box 
             
             
               110 
               small apertures in top wall of fixture box 
             
             
               T 
               thickness of ceiling covering 
             
             
                 
             
           
        
       
     
   
   DETAILED DESCRIPTION OF THE INVENTION 
   With reference to  FIG. 1 , a first embodiment is shown of an adjustable hanger assembly  20  according to the present invention. The adjustable hanger assembly  20  includes an elongated tubular member  22  having two ends  24  and  26  and a central bore  28 , a threaded bore portion  30  in the central bore  28  at the second end  26  of the tubular member  22 , a threaded rod  32  rotatably received in the threaded bore portion  30 , a first joist engaging member  34  rotatably attached to the first end  24  of the tubular member  22 , and a second joist engaging member  36  rigidly fastened to the threaded rod  32 . A fixture box assembly  38  is secured to the tubular member  22 . The fixture box assembly  38  includes a fixture box  40  with a lower edge  42 . The adjustable hanger assembly  20  includes a pair of downward depending legs  44  integral with the first joist engaging member  34  and a pair of downward depending legs  44  integral with the second joist engaging member  36 . 
   Referring to  FIG. 12 , the fixture box assembly  38  includes a two-piece bracket arrangement  45  including a top mounting plate  46  and a lower mounting plate  48  that clamp around the tubular member  22 . Screws  50 , one of which is in view in  FIG. 12 , secure the lower mounting plate  48  to the top  52  of the fixture box  40 . A fastening arrangement  53  secures the fixture box  40  to the tubular member  22 . The fastening arrangement  53  includes fasteners  54  that extend from the fixture box  40  and are received in threaded bores  56  in opposing corners  58  of the top mounting plate  46  (see  FIG. 13 ). 
   As shown in  FIG. 2 , the fasteners  54  of the fastening arrangement  53 , being fastened into opposing corners  58  of the top mounting plate  46 , thereby straddle the tubular member  22 . The fastening arrangement  53  includes a loosened state and a tightened state. The adjustable hanger assembly  20  is typically shipped with the fasteners  54  in the tightened state, which includes the fasteners  54  tightened into the threaded bores  56  in the top mounting plate  46  and the fixture box assembly  38  secured tightly to the tubular member  22 . 
   As shown in  FIG. 12 , in the tightened state, the fixture box  40  is prevented from axial rotation with respect to the tubular member  22  by the top mounting plate  46  and lower mounting plate  48  being clamped around the polygonal shaped tubular member  22 . In the tightened state, the fixture box  40  is also fixed longitudinally in one position along the tubular member  22 . By slightly loosening the fasteners  54  of the fastening arrangement  53 , the fixture box  40  is placed in its loosened state and is rendered slideable with respect to the tubular member  22 . Since screws  50  remain in place, securing the lower mounting plate  48  to the fixture box  40 , and the fasteners  54  remain in place straddling the tubular member  22 , the fixture box  40  can be slid along the tubular member  22  to the desired position whereupon the fasteners  54  are tightened thereby clamping the fixture box  40  to the tubular member  22 . 
   With reference to  FIG. 3 , the fastening arrangement  53  in the loosened state therefore enables sliding of the fixture box  40  linearly along the tubular member  22  in such a manner that the lower edge  42  of the fixture box  40  slides along a plane  60  parallel to and at a fixed distance from the tubular member  22 . 
   With further reference to  FIG. 3 , the downward depending legs  44  of the adjustable hanger assembly  20  include lower surfaces  62 . The lower surfaces  62  of the legs  44 , when oriented on the tubular member  22  in the same direction as the fixture box  40 , intersect a first plane  64  equidistant from a second plane  60  through the lower edge  42  of the fixture box  40 . The first plane  64  is offset from the second plane  60  preferably by the thickness T of the ceiling covering  66  that will be used in conjunction with the adjustable hanger assembly  20 . 
   As shown in  FIGS. 2 and 3 , the adjustable hanger assembly  20  includes one or more outwardly extending spikes  68  on the first and second joist engaging members  34  and  36 . 
   With reference to  FIGS. 3 ,  4 , and  6 , the downward depending legs  44  are substantially V-shaped when viewed from a distance beyond the first  24  and second  26  ends of the tubular member  22  (see  FIG. 2 ). 
   The adjustable hanger assembly  20  is adjustable to a plurality of lengths from a fully compressed position, as shown in  FIGS. 2 and 3 , to a fully expanded position (not shown). With the lower surfaces  62  of the downward depending legs  44  resting on the upper surface  78  of a ceiling, a portion  66  of which is shown in  FIG. 3 , the tubular member  22  can be rotated to change the length of the adjustable hanger assembly  20 . The length of the adjustable hanger assembly  20  at the fully compressed position is 13.37 inches and the length at the fully expanded position (not shown) is 24.5 inches. Thus the adjustable hanger assembly  20  is capable of spanning the distance between the joists of most building structures. 
   With reference to  FIG. 14 , the adjustable hanger assembly  20  of the present invention is typically used to support an electrical fixture  70  (portion shown) from overhead joists  72  covered by a ceiling covering  66  through which a hole  74  has been made. The adjustable hanger assembly  20  is initially in the fully collapsed position and with the fixture box assembly  38  secured firmly to the tubular member  22 . The adjustable hanger assembly  20  is placed in operation by first passing the adjustable hanger assembly  20  through the hole  74  in the ceiling covering  66 . The adjustable hanger assembly  20  is placed on the ceiling covering  66  in such a manner that the first joist engaging member  34  is in contact with a first  76  of the overhead joists and the pairs of downward depending legs  44  rest upon the top surface  78  of the ceiling covering  66 . The tubular member  22  is then rotated in a first direction to thereby increase the length of the adjustable hanger assembly  20 . The rotation of the tubular member  22  is continued until the outwardly extending spikes  68  on the first joist engaging member  34  and the outwardly extending spikes  68  on the second joist engaging member  36  are driven completely into the overhead joists  76  and  80  and the adjustable hanger assembly  20  is firmly wedged between the overhead joists. The fastening arrangement  53  is then placed in the loosened state thereby making the fixture box  40  slideable with respect to the tubular member  22 . The fixture box  40  is then slid along the tubular member  22  until the fixture box  40  is aligned above the hole  74 . The fastening arrangement  53  is then converted to the tightened state to secure the fixture box  40  in a fixed position with respect to the tubular member  22 . 
   Referring to  FIGS. 8-11 , a preferred embodiment of the fixture box  40  is shown. The fixture box  40  includes a top wall  82 , a sidewall  84 , corners  86 , an inner cavity  88 , a tab  90 , openings  91  in the sidewall  84 , and two lugs  92  on opposite corners  86  secured to the fixture box  40  by rivets  94 . As shown in  FIG. 11 , the top wall  82  includes one or more knockout wall portions  96 . The sidewall  84  of the fixture box  40  may also include knockouts  96 . The lugs  92  are secured at opposite corners  86  of the fixture box  40  or 180° apart on opposite sides of the sidewall  84  in order to evenly distribute the suspended load of an installed fixture (not shown) directly under the tubular member  22  as shown in  FIG. 2 . The lugs  92  are right-angle shaped bars that extend through the openings  91  in the sidewall  84  of the fixture box  40  and are fastened to the sidewall  84  by rivets  94  (see FIG. 
   By supporting the load from the lugs  92 , it is possible to construct the fixture box  40  from thinner metal such as 0.063 inch thick galvanized steel or plated steel. The lugs  92  are constructed of thicker metal, such as 0.125 inch thick galvanized steel or plated steel to withstand the stress of a supported load, which may be a fan weighing up to 35 pounds or an electrical fixture weighing up to 50 pounds. By supporting the suspended load from the lugs  92 , which are typically 0.125 inch thick, the top wall  82  and sidewall  84  of the fixture box  40  may be constructed of much thinner metal, such as 0.063 inch thick steel, to lower production cost of the fixture box  40 . 
   With reference to  FIGS. 8 and 11 , the tab  90  is preferably a bent over portion of the sidewall  84  and offers temporary storage receptacles  100  for the fixture fasteners  102  that will be used to support the suspended load. The temporary storage receptacles  100  are threaded bores that match the threads of the fixture fasteners  102 . The fixture fasteners  102  are preferably load bearing fasteners #10-32×⅞″ philips/slotted combo serrated hexagon washer head screws or larger. The lugs  92  include permanent receptacles  104  to receive the fixture fasteners  102  after they are removed from the temporary storage receptacles  100  in the tab  90 . The permanent receptacles  104  for the fixture fasteners  102  are on the centerline  11 - 11  diagonally through the fixture box  40 , as shown in  FIG. 8 . Thus, all the fasteners that are needed to complete the installation of a ceiling fan or ceiling electrical fixture (not shown) are included integrally with the adjustable hanger assembly, which is a significant advantage to the installer who will not be forced to search for fasteners and other components at the job site. As shown in  FIG. 11 , the fixture fasteners  102 , when “parked” in the temporary storage receptacles  100 , do not extend beyond the lower edge  42  of the fixture box  40 . Thus the overall profile of the adjustable hanger assembly  20  is minimized to create a compact package for easy storage and transport. 
   With reference to  FIGS. 8-10 , the fixture box  40  portion of the adjustable hanger assembly my further include a C-shaped fitting  106 , such as the BLACK BUTTON™ push-in connectors available from Arlington Industries, Inc., 1 Stauffer Industrial Place, Scranton, Pa. The fitting  106  could be snapped into the knockout  96  to provide a quick snap-in type fitting that provides strain relief to any non-metallic cable (not shown) later inserted therethrough. 
   As shown in  FIG. 8 , the top wall  82  of the fixture box  40  includes large apertures  108  and small apertures  110 . The small apertures  110  will later accommodate the fasteners  50  that will secure the lower mounting plate  48  (see  FIG. 12 ) to the fixture box  40 . The large apertures  108  will later accommodate the fasteners  54  (see  FIG. 12 ) that will secure the top mounting plate  46  to the lower mounting plate  48 . 
   Having thus described the invention with reference to a preferred embodiment, it is to be understood that the invention is not so limited by the description herein but is defined as follows by the appended claims.