Abstract:
A light fixture mounting post includes an upper threaded portion for attaching the post to a light shade and a lower portion for attaching light fixtures to the post. The upper threaded portion has left handed threads, and an O-ring and a shaped rubber washer residing between a post nut and the shade. A post flange limits the insertion depth of the upper threaded portion through the shade. The threaded segments include right handed pipe threads for tightly engaging the light fixtures. Embodiments include a continuous lower portion with straight or tapered threads and a segmented lower portion with reduced thickness spaces separating the taper or straight threaded segments allowing easy shortening of the lower portion.

Description:
[0001]    The present application is a Continuation In Part of U.S. patent application Ser. No. 12/906,404 filed Oct. 18, 2010, and a Continuation In Part of U.S. patent application Ser. No. 14/054,535 filed Oct. 15, 2013, which applications are incorporated in its entirety herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to light fixtures and in particular to light fixture mounting posts. 
         [0003]    Known light fixture mounting posts comprise a hollow threaded tube which is screwed into a base unit and a light fixture is screwed onto, with wiring running through the tube into the light fixture. A single post length is often not suitable for a specific installation, or the tube requires a nut to tighten to fix the position of the light fixture on the tube, and such nuts are often very difficult to tighten, resulting in a loose fixture. 
       BRIEF SUMMARY OF THE INVENTION 
       [0004]    The present invention addresses the above and other needs by providing a light fixture mounting post which includes an upper threaded portion for attaching the post to a light shade and a lower portion for attaching light fixtures to the post. The upper threaded portion has left handed threads, and an O-ring and a shaped rubber washer residing between a post nut and the shade. A post flange limits the insertion depth of the upper threaded portion through the shade. The threaded segments include right handed pipe threads for tightly engaging the light fixtures. Embodiments include a continuous lower portion with straight or tapered threads and a segmented lower portion with reduced thickness spaces separating the taper or straight threaded segments allowing easy shortening of the lower portion. shoulder which facilitates the attachment of known light fixtures. 
         [0005]    In accordance with one aspect of the invention, there is provided a light fixture mounting post having a plurality of segments, wherein each segment includes a new tapered thread. The post is cut to the desired length, and the fixture is screwed onto the tapered thread until it is tight, therefore not requiring a nut because of the taper, and correctly positioning the light fixture. 
         [0006]    In accordance with another aspect of the invention, there is provided a continuous light fixture mounting post having either straight or tapered thread. 
         [0007]    In accordance with still another aspect of the invention, there is provided a light fixture mounting post having a short unthreaded shoulder between sequential threaded segments. The vertical positioning of light fixtures is often critical in obtaining a desired light appearance. Each threaded segment includes tapered pipe threads which limit the ability to vertically position the light fixtures and in some instances there is a need to position the light fixtures lower. Providing the unthreaded shoulder (shorter than the threaded segments) allows additional options for vertically positioning the light fixture. 
         [0008]    In accordance with yet another aspect of the invention, there is provided a light fixture mounting post having a hexagonal shoulder which engages a hexagonal passage in a light shade to prevent the mounting post from rotating in the light shade when a light fixture is attached or removed from the taper threaded post. 
         [0009]    In accordance with still another aspect of the invention, there is provided a light fixture mounting post having left handed threads on an upper portion which engages the light shade to prevent the mounting post from rotating in the light shade when a light fixture is removed from the taper threaded post. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0010]    The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein: 
           [0011]      FIG. 1  is a perspective view of a light assembly according to the present invention. 
           [0012]      FIG. 2  is a perspective view of the separate elements of the light assembly according to the present invention. 
           [0013]      FIG. 3  is a perspective view of a light fixture mounting post according to the present invention. 
           [0014]      FIG. 4A  is a side view of the light fixture mounting post attached to a light shade according to the present invention. 
           [0015]      FIG. 4B  is a top view of the light fixture mounting post attached to the light shade according to the present invention. 
           [0016]      FIG. 4C  is a bottom view of the light fixture mounting post attached to the light shade according to the present invention. 
           [0017]      FIG. 5  shows a top view of a center of a light shade according to the present invention. 
           [0018]      FIG. 6A  is a side view of the light fixture mounting post alone according to the present invention. 
           [0019]      FIG. 6B  is a top view of the light fixture mounting post alone according to the present invention. 
           [0020]      FIG. 6C  is a bottom view of the light fixture mounting post alone according to the present invention. 
           [0021]      FIG. 7  is a cross-sectional view of the light fixture mounting post according to the present invention taken along line  7 - 7  of  FIG. 6A . 
           [0022]      FIG. 8A  is a side view of the light fixture mounting post nut according to the present invention. 
           [0023]      FIG. 8B  is a top view of the light fixture mounting post nut according to the present invention. 
           [0024]      FIG. 8C  is a bottom view of the light fixture mounting post nut according to the present invention. 
           [0025]      FIG. 9  is a cross-sectional view of the light fixture mounting post nut according to the present invention taken along line  9 - 9  of  FIG. 8A . 
           [0026]      FIG. 10A  is a side view of a second embodiment of the light fixture mounting post according to the present invention. 
           [0027]      FIG. 10B  is a top view of the second embodiment of the light fixture mounting post according to the present invention. 
           [0028]      FIG. 10C  is a bottom view of the second embodiment of the light fixture mounting post according to the present invention. 
           [0029]      FIG. 11  is a cross-sectional view of the second embodiment of the light fixture mounting post according to the present invention taken along line  11 - 11  of  FIG. 10A . 
       
    
    
       [0030]    Corresponding reference characters indicate corresponding components throughout the several views of the drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0031]    The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims. 
         [0032]    A perspective view of a light assembly  10  according to the present invention is shown in  FIG. 1  and a perspective view of the separate elements of the light assembly  10  is shown in  FIG. 2 . The light assembly  10  includes a light fixture mounting post nut  11 , an O-ring  12 , a light shade  14 , a shaped rubber washer  13 , a light fixture mounting post  16 , and a light fixture  18 . The light shade  14  includes a larger bowl shaped shading portion  14   a  and a smaller upper attaching portion  14   b  for attaching the light fixture mounting post  16 . The shaped rubber washer  13  provides a seal between the post  16  and the shade  14   a . The light fixture  18  may be any fixture which may support a light and/or provide electrical connections to a light, or a second fixture which may support a light and/or provide electrical connections to a light. 
         [0033]    A perspective view of the light fixture mounting post  16  is shown in  FIG. 3 . The light fixture mounting post  16  includes an upper portion  20  for attaching to the attaching portion  14   b , a post flange  22 , and a lower portion for attaching the light fixture  18 . 
         [0034]    A side view of the light fixture mounting post  16  attached to the attaching portion  14   b  of the light shade  14  is shown in  FIG. 4A , a top view of the light fixture mounting post  16  attached to the attaching portion  14   b  is shown in  FIG. 4B , a bottom view of the light fixture mounting post  16  attached to the attaching portion  14   b  is shown in  FIG. 4C , and a top view of a center portion of the lamp shade is shown in  FIG. 5 . The attaching portion  14   b  includes a non-round (for example, hexagonal) passage  15  and the light fixture mounting post  16  includes a cooperating non-round (for example, hexagonal) shoulder  34  (see  FIG. 6A ) on a flange  22  on the light fixture mounting post  16 . The shoulder  34  preferably engages the passage  15  to restrict or prevent rotation of the light fixture mounting post  16  once attached to the light shade  14 , for example, when the light fixture  18  is attached to or detached from the light fixture mounting post  16 . However, other center portion structure may be provided to cooperate with the light shade to resist rotation of the mounting post with respect to the light shade. For example, a tapered shoulder providing an interference fit, a rough top surface of the flange  22 , a star washer between the flange  22  and light shade  14 . The shaped washer  13  is sandwiched between the nut  11  and light shade  14 . The O-ring  12  is concealed between the nut  11  and shaped washer  13 . While a hexagonal shaped shoulder  34  is preferred, any non-round shape may be sufficient to restrict rotation of the light fixture mounting post  16 . 
         [0035]    The mounting post  16  includes a left hand threaded upper portion  20  and a lower portion  21  having spaced apart tapered pipe threaded segments  29  separated by spaces  28 . The lower portion  21  also includes an unthreaded shoulder  30  adjacent to a space  28  for extending threaded segments  29  below the unthreaded shoulder  30  downward. The unthreaded shoulder  30  provides additional length to the lower portion  21  which facilitates the attachment of known light fixtures. The spaces  28  preferably have reduced thickness to allow easier shortening of the lower portion  21 . 
         [0036]    A side view of the light fixture mounting post  16 , according to the present invention, is shown in  FIG. 6A , a top view of the light fixture mounting post  16  is shown in  FIG. 6B , a bottom view of the light fixture mounting post  16  is shown in  FIG. 6C , and a cross-sectional view of the light fixture mounting post  16  taken along line  7 - 7  of  FIG. 6A  is shown in  FIG. 7 . The flange  22  positions the light shade  14  on the mounting post  16  and the hexagonal shoulder  34  is formed on the flange  22 . 
         [0037]    The mounting post  16  includes left hand male threads T 1  and female threads T 2  on the upper portion  20  and male threads T 3  on the lower portion  21 . 
         [0038]    The threads T 1  are preferably ¾ inch or ⅞ inch National Pipe Thread (NPT) or National Pipe Straight (NPS). 
         [0039]    The threads T 2  are preferably ½ inch or ¾ inch and NPT or NPS by 14. 
         [0040]    The threads T 3  are preferably ½ inch or ¾ inch and NPT or NPS by 14. 
         [0041]    The lower portion  21  has a length L 1 , the flange  22  has a length L 2 , the hexagonal shoulder  34  has a length L 3 , the threads T 1  have a length L 4 , the spaces  28  between threaded segments  29  have a length L 5 , the threaded segments  29  have lengths L 6 , and the unthreaded shoulder  30  has a length L 7 . The hexagonal shoulder  34  has a land width W 1 , the mounting post  16  has an inside diameter D 1 , and the flange  22  has an outside diameter D 2 . The length L 1  is preferably approximately 3.74 inches. The length L 2  is preferably approximately 0.25 inches. The length L 3  is preferably approximately 0.25 inches, the length L 4  is preferably approximately 0.575 inches, the length L 5  is preferably approximately 0.085 inches, the length L 6  is preferably approximately 0.66 inches, the length L 7  is preferably approximately 0.1445 inches, the width W 1  is preferably approximately 1.3172 inches, the diameter D 1  is preferably approximately 0.455 inches, and the diameter D 2  is preferably approximately 1.3172 inches. 
         [0042]    A side view of the light fixture mounting post nut  11  according to the present invention is shown in  FIG. 8A , a top view of the light fixture mounting post nut  11  is shown in  FIG. 8B , a bottom view of the light fixture mounting post nut  11  is shown in  FIG. 8C , and a cross-sectional view of the light fixture mounting post nut  11  taken along line  9 - 9  of  FIG. 8A  is shown in  FIG. 9 . The nut  11  includes a nut flange  38  and a nut hexagonal portion  36  extending from the nut flange  38 . A nut recess  42  is preferably provided on a bottom surface  40  of the nut  11  providing clearance for any portion of the hexagonal shoulder  34  reaching above the light shade  14  (see  FIG. 2 ). The bottom surface  40  further preferably includes an O-Ring recess  44  for accepting the O-Ring  12  (see  FIG. 2 ). The post nut  11  includes female threads T 4  for cooperating with male threads T 1  (see  FIG. 6A ). 
         [0043]    The nut flange  38  has a length L 8  and diameter D 3 , and the nut hexagonal portion  36  has a length L 9  and a land width W 2 . The length L 8  is preferably approximately 0.177 inches, the diameter D 3  is preferably approximately 2.08 inches, the length L 9  is preferably approximately 0.391 inches, and the land width W 2  is preferably approximately 1.8 inches. The nut recess  42  had a length L 10  and a diameter D 4 , and the O-Ring recess  44  is preferably circular and has a semi-circular cross-section with a radius R. The length L 10  is preferably approximately 0.25 inches, the diameter D 4  is preferably approximately 1.5 inches, and the radius R is preferably approximately 0.05 inches. 
         [0044]    A side view of a second embodiment of the light fixture mounting post  16 ′ according to the present invention is shown in  FIG. 10A , a top view of the light fixture mounting post  16 ′ is shown in  FIG. 10B , a bottom view of the light fixture mounting post  16 ′ is shown in  FIG. 10C , and a cross-sectional view of the light fixture mounting post  16 ′ taken along line  11 - 11  of  FIG. 10A  is shown in  FIG. 11 . The light fixture mounting post  16  is similar to the light fixture mounting post  16  except the lower portion  21 ′ is continuous with threads T 2  and T 4  described above. 
         [0045]    While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.