Patent ID: 7431482

Claim:
A modular downlight assembly comprising: a back housing for mounting in a cavity formed in one of a conventional ceiling and dropped ceiling comprising a frame of inverted channel section with opposite sidewalls extending downwards from opposite sides of a channel base wall and free, lower ends of the sidewalls defining a channel mouth so that the housing can be mounted in the ceiling cavity with the sidewalls and base concealed within the cavity and the channel mouth opening to below the ceiling; a plurality of apertures of a same size as each other formed in the base wall for receiving, respectively, when mounted in the cavity, selected individual downlight modules; respective groups of downlight module attachment means on the base wall spaced around respective apertures, the attachment means of one group being at a similar spacing in respect to an aperture as the spacing of an attachment means of any other group to an aperture; a plurality of downlight modules each comprising a lamp holder housing suspended from a lower face of a mounting plate by one of an extensible toggle linkage and an extensible scissor linkage; the mounting plates all having module attachment means at a same location to permit registration and fastening of a mounting plate of any selected module with any selected one of the module attachment means of the back housing; each downlight module comprising a junction box mounted to an upper face of each mounting plate and carrying a power supply, being one of a transformer and a ballast; the junction boxes and power supplies of all modules being within a cross-sectional envelope smaller than any one of the apertures in the back housing base wall and the mounting plates being sized for engagement with the base wall at edge portions of respective apertures so as to cover respective apertures when the attachment means on the mounting plates and the base wall are engaged to mount the selected modules in the back housing with the power supply extending through the aperture above the base into the ceiling cavity; whereby a selected, variable, number of modules can be mounted individually in a back housing which has been installed in the ceiling cavity by inserting, from below, the junction box and power supply through a selected aperture until a respective mounting plate is brought into covering relation with a respective aperture and the attachment means thereof are brought into registration with and operatively engage respective downlight module attachment means on the base wall; and whereby a selected, variable, number of modules can be demounted and removed individually from below from the back housing which remains installed in the ceiling cavity by disengaging said attachment fastening means from below and withdrawal of the respective junction boxes and power supplies from below through the respective apertures.