Emergency lighting system

An emergency lighting system for providing low voltage DC battery powered illumination to one or more areas of a home, apartment, office or other building structure in an emergency mode upon the failure or termination in such areas of a normal AC power mode, said system comprising:

• a) a hard wired smoke detector which provides through its junction box a source of normal 120 volt AC power having interconnecting power leads to the primary high voltage winding of a 10-to-1 voltage step-down transformer and forming therewith an AC power circuit;
• b) AC power rectifying means, including input terminals and output terminals, having its input terminals connected to the secondary low voltage winding of said transformer to receive 12 volt AC power therefrom and rectify said AC power to 12 volt DC power;
• c) an emergency 12 volt DC rechargeable battery power source having its terminals interconnected to the output terminals of said power rectifying means to receive 12 volt DC power for storage therein when said normal AC power source is operative;
• d) a multiplicity of 12 volt DC incandescent lamps for providing emergency illumination, said lamps interconnected in parallel to low voltage leads from the terminals of said battery power source and forming therewith an emergency DC circuit;
• e) main control relay means for interacting between said AC circuit and said DC circuit, said main relay means including DC circuit contact means interconnected in one of the low voltage leads of said DC circuit from said lamps to said battery source, and said main relay means including coil means in said AC circuit for maintaining said DC circuit contacts in their open position during AC current flow in said AC circuit and responsive to a termination or failure of said AC power source and cessation of AC current flow in said AC circuit to close said DC circuit contact means whereby said incandescent lamps are energized by said battery source to produce emergency illumination;
• and
• f) smoke detector relay means including normally closed AC circuit contact means interconnected in said AC power circuit and including means responsive to the detection of smoke by said smoke detector to open said AC circuit contact means whereby AC current flow in said AC circuit is terminated and the DC circuit contacts of said main relay means are closed whereby said incandescent lamps are energized by said battery source to produce emergency illumination.