Abstract:
A recessed light fixture includes a light source enclosure face defining an aperture. The enclosure face includes a spring retainer spaced outward from the aperture. The spring retainer includes a bridge portion forming a portion of the circumference of the aperture and a slot defined between the bridge portion and the enclosure face.

Description:
This application claims the benefit of U.S. Provisional Application Ser. No. 60/349,362, filed Jan. 22, 2002, incorporated herein by reference. 
    
    
     BACKGROUND 
     This invention relates to recessed lighting. 
     Light fixtures that are recessed in thermal barriers in buildings may form conducting thermal conduits across the barriers. For example, a light fixture recessed in a ceiling separating a heated room from an unheated attic may penetrate into insulation above the ceiling and form a low resistance path for the flow of heated air from the room to the attic, decreasing the energy efficiency of the house and increasing the monthly energy bill of the homeowner. 
     SUMMARY 
     To limit the flow of air across a thermal barrier, a recessed light fixture may include a light source enclosure face defining an aperture. The enclosure face may include a spring retainer spaced outward from the aperture. The spring retainer may include a bridge portion forming a portion of the circumference of the aperture and a slot defined between the bridge portion and the enclosure face. 
     Implementations may include one or more of the following features. For example, the enclosure face may be a reflector face. The aperture may be dimensioned to pass a connection portion of alight source. The slot may be oriented substantially transversely relative to the aperture. The bridge portion may be substantially coplanar with the enclosure face. The bridge portion may be inside the light source enclosure bounded by the enclosure face, for example, the bridge portion may be less than about ⅛ of an inch inside. The bridge portion may be joined to the enclosure face by a pair of joining portions at the ends of the bridge portion. 
     The recessed light fixture may also include a socket configured to connect to a light source. The socket may be mounted in alignment with the aperture. The recessed light fixture may also include a spring received in the slot to mount the socket in alignment with the aperture. The aperture may be substantially circular and the spring retainer may be spaced radially outward from the aperture. 
     The light source enclosure face may also include a second spring retainer including a second bridge portion forming a second portion of the circumference of the aperture and a second slot defined between the second bridge portion and the enclosure face. The spring may include a pair of legs, with each leg joined to the socket and having a curved latching end. The spring retainers may be diametrically opposed about the aperture. 
     In another general aspect, a recessed light fixture includes a light source enclosure face defining an aperture and a slot spaced outward from the aperture. The slot may be oriented substantially transversely relative to the aperture. 
     Implementations may include one or more of the following features and one or more of the features noted above. For example, the light source enclosure face may define a second slot spaced radially outward from the aperture. The second slot may be oriented substantially transversely relative to the aperture. The slots may be diametrically opposed about the aperture. The aperture may be substantially circular, and the slot may be spaced radially outward from the aperture. 
     The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims. 
    
    
     DESCRIPTION OF DRAWINGS 
     FIG. 1 is schematic view of a recessed light fixture in a ceiling of a building. 
     FIG. 2 is a side view of a reflector portion of the recessed light fixture of FIG. 1 with a mounted socket. 
     FIG. 3 is a top view of the reflector portion of the recessed light fixture of FIG.  2 . 
     FIG. 4 is a diagrammatic view of the reflector portion of FIG.  2 . 
     FIG. 5 is a sectional view of the reflector portion of FIG. 2 taken along the section  5 — 5  of FIG.  3 A. 
     FIG. 6 is a top view of the reflector portion of FIG. 2 with the mounted socket. 
     FIG. 7 is a sectional view of the reflector portion of FIG. 2 taken along section  7 — 7  of FIG. 6 during mounting of the socket. 
     FIG. 8 is a sectional view of the reflector portion of FIG. 2 taken along section  7 — 7  of FIG. 6 after mounting of the socket. 
    
    
     DETAILED DESCRIPTION 
     Referring to FIG. 1, a recessed light fixture  100  is recessed in a ceiling  105  to illuminate a room  110  in a building. Ceiling  105  is part of a thermal barrier between room  110  and an attic  115 . Ceiling  105  is supported by ceiling joists  120  and covered by thermal insulation  125 . Light fixture  100  penetrates into the thermal barrier separating room  110  and attic  115 , but limits the flow  130  of air between room  110  and attic  115  due to the penetration. 
     Referring to FIG. 2, recessed light fixture  100  includes a reflector chamber  200 , a connection rivet  205 , a socket  210 , and a spring retainer  215 . Reflector chamber  200  encloses a bulb  220  and reflects downward light emitted by bulb  220 . Connection rivet  205  joins spring retainer  215  to socket  210 . Socket  210  is releasably mounted to reflector chamber  200  by spring retainer  215  and forms a mechanical and electrical connection to bulb  220  to retain bulb  220  in position and supply bulb  220  with power. 
     Reflector chamber  200  has an upper face  225  that defines a substantially circular aperture  230  and includes a pair of spring receivers  235 . Aperture  230  is bounded by a circumferential wall  240 . 
     Socket  210  includes a socket body  245  with a top face  250  and an opposing bottom face  255 . Bottom face  255  is joined to an annular lip  260 . Annular lip  260  is dimensioned to be insertable into aperture  230  so that bottom face  255  of socket  220  abuts reflector upper face  225 . Socket body  245  and annular lip  260  together define a female threaded chamber  265  for connecting to a threaded portion  270  of bulb  220 . 
     Spring retainer  215  is generally shaped like an inverted “U” and includes a top flat portion  275  joined to a pair of downwardly extending lateral legs  280 . Each of legs  280  includes an arcuate lever portion  285  and an insertable latch portion  290 . Each lever portion  285  bends outwardly away from the opposite leg  280  and provides a surface that an operator can manipulate to press legs  280  together. Latch portions  290  are disposed at the end of respective legs  280  and are curved outwardly for mating with spring receivers  235  to mount socket  210  to reflector chamber  200 . 
     Referring to FIG. 3, which illustrates upper face  225  of reflector chamber  200  without socket  210  or spring retainer  215  being present, spring receivers  235  are disposed on diametrically opposite sides of the circumferential wall  240  of aperture  230  to receive latch portions  290  of a straight spring retainer  215  (not shown). 
     Referring also to FIG. 4, each spring receiver  235  includes a stamped bridge portion  400 , a pair of joining portions  405  on opposite sides of bridge portion  400 , and an upper face wall  410 . Bridge portions  400  are substantially coplanar with upper face  225  but depressed into reflector chamber  200  by, for example, stamping. Bridge portions  400  include an inner radial face  415  and an outer face  420 . Inner radial face  415  is formed from the circumferential aperture wall  240  when bridge  400  is depressed into reflector chamber  200 . Outer face  420  separates from upper face wall  410 , for example, during stamping. Joining portions  405  rise from bridge portion  400  to join with reflector face  225  and maintain bridge portions  400  in a fixed position below reflector face  225 . 
     Referring also to FIG. 5, outer radial face  420 , joining portions  405 , and upper face wall  410  together define a pair of opposing slots  500  disposed radially outward from circumferential aperture wall  240 . Slots  500  are dimensioned to receive latch portions  290  of spring retainer  215 , and may have a height of D. D may be approximately equal to the thickness of latch portion  290 . For example, D may be less than ⅛ of an inch, or D may be about {fraction (1/16)} of an inch. The relatively small size of slots  500  limits air flow through slots  500  and across a thermal barrier into which light fixture  100  is recessed. 
     Referring to FIG. 6, when light fixture  100  is assembled, top flat portion  275  of spring retainer  215  traverses top face  250  of socket  210  and is joined to top face  250  at rivet  205 . Legs  280  are aligned with spring receivers  235 . 
     Referring to FIG. 7, to assemble light fixture  100 , an operator first applies a force F to each lever portion  285  to press legs  280  together and inward toward socket  210 . The operator then inserts annular lip  260  into aperture  230  such that bottom face  255  of socket  210  abuts upper face  225  of reflector chamber  200 . Socket  210  is rotated so that latch portions  290  are aligned with slots  500 . 
     Referring to FIG. 8, the operator then releases lever portions  285 , which permits spring retainer legs  280  to expand to slide latch portions  290  into slots  500  and retain socket  210  at upper surface  225 . Sliding latch portions  290  into slots  500  fills at least a portion of slots  500  and limits air flow across a thermal barrier into which light fixture  100  is recessed. 
     When assembled, annular lip  260  extends past inner radial faces  415  of the bridges  400  to loosely seal aperture  230  and minimize the flow of air between socket  210  and reflector chamber  200 . This too limits air flow across a thermal barrier into which light fixture  100  is recessed. 
     A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made. For example, the shape of spring retainer  215  may be changed. Accordingly, other implementations are within the scope of the following claims.