Abstract:
Apparatus and method for mounting a downrod, and therefore a fixture, to a ceiling, according to which an adapter is disposed in a bore of a hanger ball that is connected to the ceiling, a portion of the downrod is disposed in a bore of the adapter and the downrod is between the hanging ball and the fixture.

Description:
BACKGROUND 
   This invention relates to an apparatus for mounting a fixture to a ceiling utilizing a downrod extending between the fixture and the ceiling. 
   Various ceiling-mountable fixtures, such as fans, lights (semiflushes, chandeliers, pedants, etc,) are usually connected to an electrical box, terminal, or the like, at the ceiling. When it is desired to lower the fixture from the ceiling, a downrod is often connected between the electrical box, or terminal and the fixture. To this end, a hanger ball has been used that is mounted to the ceiling and has an inner bore that receives the upper end portion of the downrod in a manner so that the downrod can be hung from the hanger ball. 
   The diameter of the bore of the hanger ball should correspond to the outer diameter of the downrod so that the end portion of the downrod can fit in the bore with minimum clearance to insure a stable connection. However, the diameters of the downrods often vary, creating a compatibility problem with the hanger ball, and vice versa. 
   Therefore, what is needed is an adapter to enable a downrod to be connected to a hanger ball in a stable manner despite variances in the diameter of the downrod and the bore of the hanger ball. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an elevational view of an assembly according to an embodiment of the present invention. 
       FIG. 2  is an exploded view of the assembly of  FIG. 1 . 
       FIG. 3  is a sectional view of the assembly of the embodiment of  FIG. 1  in an assembled condition. 
       FIG. 4  is a sectional view taken along the line  4 — 4  of  FIG. 2 . 
   

   DETAILED DESCRIPTION 
   Referring to the drawings, the reference  10  refers, in general, to a downrod having an upper end portion, as viewed in the drawing, extending in, and connected to, a hanger ball  12  in a manner to be explained. It is understood that the hanger ball  12  is designed to be connected to a ceiling via a conventional mounting bracket, or the like not shown). The other end portion of the downrod  10  is adapted for connection, in a conventional manner, to a fixture, such as a ceiling fan, light fixture, or the like, (not shown) in a spaced relation to the ceiling. 
   The downrod  10  is tubular and has two aligned, diametrically opposed, openings  10   a  and  10   b  ( FIG. 3 ) extending through its wall near its upper end and transverse to the longitudinal axis of the downrod. A ground screw  14  extends through an opening in the upper end portion of the downrod  10  for the purpose of enabling a ground conductor from the ceiling and/or the fixture to be electrically and mechanically connected to the downrod. The remaining electrical conductors from the ceiling and/or the fixture can be threaded through the hanger ball  12  and the downrod  10 , in a conventional manner. 
   The hanger ball  12  is spherical in shape and has an internal bore  12   a . Two diametrically opposed slots  12   b  and  12   c  are formed in the hanger ball  12  that extend from the bore and from the upper end of the ball. A groove  12   d  is provided in the upper end portion of the hanger ball  12  to permit access to the ground screw  14 . 
   It will be assumed that the hanger ball  12  is designed to be used with a downrod having a diameter corresponding to the diameter of its bore  12 , and that the outer diameter of the downrod  10  is much less than this diameter. Hence if the downrod  10  were directly mounted in the hanger ball  12  it would create an unstable connection due to the above differences in diameters. 
   To enable the downrod  10  to be supported by the hanger ball  12  in a stable manner, a tubular adapter  20  is provided that extends between the outer diameter of the upper end portion of the downrod  10  and the bore  12   a  of the hanger ball and in a coaxial relation with the downrod and the hanger ball. The length of the adapter  20  is substantially the same as the length of the hanger ball  12 , and, as better shown in  FIGS. 3 and 4 , the outer diameter of the adapter  20  corresponds to the diameter of the bore  12   a  of the hanger ball  12  so that the adapter  20  extends in the latter bore with minimum clearance. Similarly, the bore of the adapter  20  corresponds to the outer diameter of the downrod  10  so that the upper end portion of the downrod extends in the adapter  20  with minimum clearance. 
   The wall of the adapter  20  has two aligned, diametrically opposed, openings  20   a  and  20   b  ( FIG. 3 ) extending therethrough and transverse to the longitudinal axis of the downrod. The openings  20   a  and  20   b  are aligned with the openings  10   a  and  10   b  in the downrod  10 , and a pin  22  extends through the aligned openings. The respective end portions of the pin rest on the shoulders of the hanger ball  12  formed by the slots  12   b  and  12   c , to support, or hang, the downrod  10  from the hanger ball. The axial positions of the openings  20   a  and  20   b  in the wall of the adapter  20  relative to the depth of the slots  12   b  and  12   c  of the hanger ball  12  are such that the upper ends of the downrod  10  and the adapter  20  extend flush with the upper end of the hanger ball  12 , as shown in  FIG. 3 , to enable the hanger ball to be mounted directly to the ceiling. 
   A groove  20   d  is provided in the upper end portion of the adapter  20  to permit access to the ground screw  14 . 
   As a result, the upper end portion of the downrod  10  is supported along its entire length by the adapter  20 , which, in turn, engages the bore  12   a  of the hanger ball with minimum clearance. As a result, the downrod  10  is supported by the hanger ball  12  in a very stable manner. 
   VARIATIONS 
   It is understood that several variations may be made in the foregoing without departing from the scope of the invention. For example, the upper end portion of the downrod  12  can be externally threaded and the bore of the hanger ball  12  and the adapter  20  can be internally threaded. Moreover, the grounding screw  14  could be eliminated. 
   Although only a few exemplary embodiments have been described in detail above, those skilled in the art will readily appreciate that many other variations and modifications are possible in the exemplary embodiment without materially departing from the novel teachings and advantages of this invention. Accordingly, all such variations and modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures.