Patent Publication Number: US-7588354-B1

Title: Recessed lighting fixture having a locking assembly

Description:
RELATED APPLICATIONS 
     Priority is claimed from our provisional patent application 60/871,405, filed Dec. 21, 2006, the disclosure of which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to a recessed lighting fixture having a locking assembly for mounting the fixture in the space above the ceiling with the light projecting downwards from the ceiling to illuminate the room below. 
     BACKGROUND OF THE INVENTION 
     U.S. Pat. No. 6,505,960 issued 2003 to Schubert et al, the disclosure of which is incorporated herein by reference, teaches a recessed lighting fixture comprises a housing comprising a sidewall extending downward to a lower housing aperture and terminating in a lip extending outwardly around at least a portion of the perimeter of the aperture, a slot in the sidewall extending away from the aperture and, at least one housing locking assembly positionable at a preselected height in the slot to clamp/mount the housing in an opening in a ceiling so that the housing extends into the space above the ceiling and the lip extends around a lower edge of the ceiling opening. 
     A disadvantage of the prior approach is a requirement for an additional frame resting on the ceiling surface adjacent an upper edge of the ceiling opening for sliding receipt of the housing and for clamping engagement by the locking assembly to protect the surface of the ceiling from damage from the pressure of the locking assembly when mounting the housing in the aperture. 
     An additional disadvantage is that the slot opens at a mouth at the bottom of the housing to admit the housing locking assembly resulting both in a weakening of a lower end of the housing and a broken lip at the lower end of the housing in direct engagement with the lower face of the ceiling which may not be visually pleasing. 
     SUMMARY OF THE INVENTION 
     Objects of the invention are to provide a recessed lighting fixture which obviates or ameliorates at least some of the disadvantages of the prior art. 
     According to one aspect, the invention provides a recessed lighting fixture having a locking assembly which provides an extensive edge-line engagement with a ceiling, distributing clamping force sufficiently to obviate need for an additional underlying frame to reduce contact pressure on the ceiling. 
     According to another aspect, the invention provides a recessed lighting fixture in which the lamp housing has a locking assembly mounting slot having a laterally enlarged portion to accommodate insertion of an enlarged portion of the locking assembly and, preferably, the enlarged portion of the locking assembly is laterally resilient permitting manual compaction to permit insertion through the laterally enlarged portion of the slot. 
     Such construction obviates need for the slot to open at a mouth at an edge of the housing both avoiding a consequential weakening of a lower end of the housing and enabling an unbroken lip to be provided at the lower end of the housing in direct engagement with the lower face of the ceiling for a more pleasing visual effect. 
     In addition, replacement of a locking assembly is possible with the housing assembly remaining in the installation position in the ceiling. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       In order that the invention may be readily understood, a specific example thereof will now be described with reference to the accompanying drawings in which: 
         FIG. 1  is a side view of a locking assembly according to the invention; 
         FIG. 2  is a front view of the locking assembly shown in  FIG. 1 ; 
         FIG. 3  is an exploded view of the locking assembly; 
         FIG. 4  is a diagrammatic perspective view of the locking assembly during insertion into a mounting slot of a lamp housing; 
         FIG. 5  is a cross-sectional view of the locking assembly inserted in the mounting slot, prior to a clamping step; 
         FIG. 6  is a side view of the locking assembly inserted in the mounting slot, after the clamping step; 
         FIG. 7  is a cross-sectional view of the locking assembly inserted in the mounting slot, after the clamping step; 
         FIG. 8  is a schematic side view (rotated through 90 degrees) of the locking assembly clamping the housing in a ceiling opening; and, 
         FIG. 9   a  is a schematic showing locking assemblies engaging the outside wall surface of a housing and the upper surface of the ceiling in locked positions so as to retain the housing extending through a ceiling openings, and 
         FIG. 9   b  is a schematic showing locking assemblies engaging the inside wall surface of a housing and the upper surface of the ceiling before and after locking, respectively. 
     
    
    
     DESCRIPTION OF PARTICULAR EMBODIMENT 
     As seen, for example, in  FIGS. 4-6  and  FIG. 9   a , the recessed lighting fixture comprises a lamp receiving housing  1  and a locking assembly  2 . 
     As shown in  FIGS. 1-3 , the locking assembly comprises a support member  3  pivotally connected to a latching member  4 . 
     The support member  3  is stamped and formed from a single piece of sheet metal stock with a lower strut portion  5  and an upper attachment portion  6 . 
     The strut portion  5  comprises a channel shape, ceiling engaging portion  7  having a base/foot  8  from opposite side edges of which a pair of leg forming, channel walls  9 , 9 ′ extend upwards in divergent, face to face relation and mainly obliquely of the channel axis except for portions  10 , 10 ′ of corresponding lower edges of the channel walls adjacent a lower axial end of the base  8  which extend perpendicularly to the channel axis so as to combine with a lower edge  20  of the base  8  to form a foot with a continuous, U-shape edge-line of engagement with the ceiling when clamping the housing thereagainst, as shown in  FIGS. 8 and 9A . A pair of flanges  11 , 11 ′ extend outwards from upper edge portions of the channel walls remote from the ceiling engaging foot and have respective flat, tapering, tooth forming extensions  12 , 12 ′ protruding upwards therefrom. 
     The attachment portion  6  comprises a pair of flanges  13 , 13 ′ extending outwards from upper ends of the leg form sidewalls, providing shoulders extending in a plane parallel to the base and having respective upwardly bent extensions  15 , 15 ′ in parallel, face to face relation, having opposite, (small and large), pin receiving, through-sockets  16 , 16 ′ providing a biasing spring mounting portion or yoke, having outer, rear ends of which locating tabs  17 , 17 ′ are bent towards each other with free ends  18 , 18 ′ overlapping in sliding engagement. Respective front edge portions of the shoulders are bent downwards to form housing locking feet  19 , 19 .′ 
     A pivot pin  21  has a head  22  force fitted in the small socket  16  and the shank  23  freely received in the other socket  16 ′ so as to span the extensions  15 , 15 ′. An helical compression spring  14  is mounted axially on the pivot pin so as to bias the upper ends of the legs apart. 
     The latching member  4  is stamped and formed from a single piece of sheet metal stock and comprises a bracket-form land  24 , opposite sides of which are formed with a pair of spaced apart, flange-form ears  25 , 25 ′ having through-sockets  26  freely receiving the pivot pin. 
     A finger-piece or handle  27  extends from a front end of the land  14  and has a locking tongue  28  struck from a central portion, with a tapering/wedging free end  29  extending towards the legs, perpendicularly of the handle. 
     The housing  1  is box-like and comprises a sheet metal sidewall  31  extending downward to a lower housing aperture  32  and terminating in an outwardly extending ceiling engaging lip  33  around the perimeter of the aperture. A series of vertically extending T-shaped slots  34  are struck in the (opposite) sidewalls. Series of horizontal locking grooves  35  are provided on each side of the vertical portion  36  of each slot on both opposite faces of each of the sidewalls. 
     The recessed lighting fixture is installed by raising the housing through an opening in the ceiling  37 , until the lip  33  engages the lower edge of the opening, partially inserting the strut forming legs  9 , 9 ′ into the upper end of the slot  34 , with the teeth and flanges in registration with the laterally enlarged “cross” portion  41 , and manually squeezing the upwardly bent extensions  15 , 15 ′ and therefore the adjacent ends of the legs together, against both their natural resiliency and the action of the compression spring  14 , to permit the leg flanges  11 ,  11 ′ and teeth to be inserted from the inside of the housing through the horizontal or ‘cross’ portion  41  of the slot with the legs passing through the vertical portion  36 , as shown in  FIG. 4 , until the entire strut portion  5  is located on the outside of the housing as shown in  FIG. 5 . 
     The sliding engagement of the overlapping free ends  18 , 18 ′ of the tabs  17 , 17 ′ assists in maintaining structural integrity, resisting deformation during the squeezing action. 
     Release of the extensions  15 ,  15 ′ permits the recovery of the spring and the legs to resile apart so that the teeth  12  overlie aligned serrations  35  on the outer surface of the housing and, the locking feet  19  overlie those on the inside of the housing. In this state, as shown in  FIG. 5 , the outside surfaces of the legs  9 , 9 ′ are in frictional sliding engagement with the slot edges enabling the clip to stay, temporarily in a selected position reached by sliding the latching assembly down the slot until the bottom edge of the foot  8  engages the upper surface of the ceiling  37 . The handle  27  is then pivoted towards the inside wall surface of the housing, thrusting the locking tongue  28  progressively between the legs  9 , 9 ′, pivoting the clip so that the feet  19  are drawn to seat immovably in aligned locking grooves  35  and, the teeth  12 , 12 ′ are drawn with some resilient flexure against the serrations on the outer surface of the housing until opposite edges of the tongue  28  wedge between the opposed surfaces of the legs  9 , 9 ′, clamping the locking assembly in position, as shown in  FIG. 6 . 
     Upward pivoting of the handle withdraws the locking tongue, unclamping the locking assembly to enabling readjustment of the position thereof by sliding up or down the vertical slot. 
     It will be noted that in the clamped position, the edge portions  10 , 10 ′ combine with a lower edge  20  of the base  8  to form a foot with a continuous, U-shape edge-line of engagement with the ceiling when clamping the housing thereagainst, as shown in  FIGS. 8 and 9A .