Abstract:
A semi-standard threaded base lamp assembly may be formed with a substitutable optical housing. The assembly enables a standard set of components to be assembled as a threaded base lamp, but during construction any one of a variety of specialty reflector shells may be substituted in the assembly process to specialize the lamp for a particular market, need or interest.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The invention relates to electric lamps and particularly to electric lamp assemblies. More particularly the invention is concerned with electric lamp assemblies with included shell bodies.  
         [0003]     2. Description of the Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98  
         [0004]     PAR lamps are commonly made with aluminized clear glass envelopes supported by a thread brass base. They are commonly used in indoor and outdoor fixtures without regard to esthetic appearance. Manufacturing lamps with reflectors having different colors, shapes, and other decorative aspects would be appealing in the market, but expensive in practice to make as each component would have to be performance qualified in the lamp assembly. Changes in market can be rapid, whereas redesign of manufacturing equipment is difficult and slow. There is then a need for a lamp assembly that enables rapid change in the lamp appearance, but allows a reasonably stable manufacture process.  
       BRIEF SUMMARY OF THE INVENTION  
       [0005]     A lamp may be made from a light source having a first rigid lead and a second rigid lead, the light source being fixed in position relative to at least the first lead. A coupler is formed with a first passage and a second passage, and the light source is positioned relative to the coupler with the first lead and the second lead extended through the coupler passages. A threaded base is fixed to the coupler and has a first electrically conductive exterior contact point electrically coupled to the first lead and a second electrically conductive exterior contact point electrically coupled to the second lead and electrically insulated from the first contact point. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0006]      FIG. 1  shows an exploded view of a lamp assembly.  
         [0007]      FIG. 2  shows a perspective view of the coupler.  
         [0008]      FIG. 3  shows sectional view of the assembled lamp.  
         [0009]      FIG. 4  shows a perspective view of a base. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0010]     The lamp  10  may be simply made from a light source  12 , a coupler  18 , a base  28 , and a shell  38 .  
         [0011]     The preferred light source  12  is a press sealed tungsten halogen lamp with a first rigid lead  14  and a second rigid lead  16 . The light source  12  may be fixed in position relative to at least the first lead  14  with a brace.  
         [0012]     The preferred coupler  18  is formed from an electrically insulative material, such as ceramic, but could be made from plastic or other sufficiently rigid and electronically insulating material. The preferred coupler  18  is cylindrical with a latching structure  20  on a first end and a blocking face  22  on a second end. The preferred latching structure  20  is a threading, but may be a formed depression or protrusion that the base  28  may be fixed to, for example by peening the metal base  28  to the coupler  18 . The preferred blocking face  22  is a radially extending flange, but may be any similar set of protrusions to block axial motion through a closely formed passage. The coupler  18  is further formed with a first passage  24  and a second passage  26 . The passages  24 , and  26  extend from the first end to the second end of the coupler  18 . The light source  12  is positioned relative to the coupler  18  with the first lead  14  and the second lead  16  extended through the respective passages  24 ,  26 . A snug fit between the leads  14 ,  16  and the respective passages  24 ,  26  is preferred to properly locate and stabilize the light source  12 . The ceramic coupler  18  then centers the light source  12  with respect to the reflector shell  38 . The coupler  18  electrically isolates the leads  14 ,  16 , the base  28  and light source  12 .  
         [0013]      FIG. 4  shows a perspective view of a base  28 . The preferred threaded base  28  is a standard brass or aluminum threaded cup shaped base that is sized and shaped so as to be threadable into an appropriately sized lamp socket. The base  28  may be fixed to the coupler  18  by threading it onto the coupler  18  with or without glue, or alternatively by threading it in place and peening portions of the base  28  to lock with corresponding indents or protrusions formed on the coupler  18 . The base  28  has a first electrically conductive exterior contact point  32 , that is electrically coupled to the first lead  14  for example by welding or soldering. The base  28  also has a second electrically conductive exterior contact point  34  electrically coupled to the second lead  16 , for example by welding or soldering. The first electrically conductive exterior contact point  32  and the second electrically conductive exterior contact point  34  are electrically insulated with respect to each other, for example by an intermediate glass gob  36 .  
         [0014]     The preferred reflector shell  38  forms an optical housing around the light source  12 , and includes a defined housing passage  40 . The coupler  18  extends through the housing passage  40 , and the optical shell  38  is fixed between respective faces of the coupler  18  and threaded base  28 . The blocking face  22  may abut a face edge of the shell passage  40  to fix the axial location of the coupler  18  in the shell  38 . The shell  38  may include a mirrored or similar formed reflective surface  48  to project light received from the light source in a desired beam pattern. Alternatively, the shell  38  may include colored, decorated, artistically shaped or similarly specialized features.  
         [0015]     The preferred lamp  10  includes a first fitting  42  intermediate the coupler  18  and the optical shell  38 . The first fitting  42  may be a compressible ring positioned between and conforming to a face of the coupler  18  and a face of the shell  38 , for example a high temperature nylon washer.  
         [0016]     The preferred lamp may also include a second fitting  44  intermediate the threaded base  28  and the shell  38 . Again, the second fitting  44  may be a compressible ring positioned between the blocking face of the threaded base  28  and a face of the optical shell  38 , for example a high temperature nylon washer.  
         [0017]     The lamp  10  is assembled by positioning the light source  12  leads  14 ,  16  in the coupler  18  passages  24 ,  26 . This subassembly is then threaded through the defined passage in the shell  38  with (or without if preferred) the optional first fitting  42 . The second fitting  44 , if any, is assembled over the coupler  18  and adjacent the shell  38 . The coupler  18  is then fixed to the base  28  from the other side of the shell  38 , for example by threading the two together with glue, or peening the base  28  to fit to the coupler  18 . This joining traps the shell  38  intermediate the coupler  18  and the base  28 , with any included first fitting  42  or second fitting  44 . In the preferred embodiment the intermediate fittings  42  and  44  are used to cushion the contacts between the coupler  18  and the shell  38  and between the base  28  and the shell  38 , for example by using compressible washers as fittings.  
         [0018]     The reflector shell  38  may be closed by an optional light transmissive lens  46 . The lens  46  may be glued or melt fused to the shell  38  to enclose a cavity including the light source  12 .  
         [0019]     The assembly may be adapted for a variety of pre-made shells having a particular artistic, optical or other special reflector or shell feature. For example differing colors, optical surfaces, or other attributes may be molded in or otherwise made part of the shell. In this way a variety of special or small volume production lamps may be made only changing the single shell component. Soft glasses are the most readily adapted for such specialized shell construction, but are at the same time friable, scratchable or otherwise subject to injury in assembly. They can also have significant thermal expansion, making them difficult to build into standard lamp constructions. The preferred construction is then particularly useful when using a soft glass, such as a high expansion glass reflector (shell) since there is an opportunity that materials with differing thermal expansion rates and abrasive surfaces to come in contact with the soft glass reflector can result in glass failure. The coupler mechanically supports the reflector shell. The use of threads on the coupler reduces or eliminates the need to use adhesives to hold the assembled reflector and lamp. The threading to the base also provides the mechanical means to compress the reflector between the fittings or washers and the threaded metal base. While the assembly is oriented to small volume productions, it enables quickly variable constructions for particular, unique or artistic uses.  
         [0020]     While there have been shown and described what are at present considered to be the preferred embodiments of the invention, it will be apparent to those skilled in the art that various changes and modifications can be made herein without departing from the scope of the invention defined by the appended claims.