To provide a floodlight easy to use and suitable to emergency use by charging a secondary battery through a charging circuit when a lamp it turned on with AC current, and forcing the lamp to connect to the secondary battery by the operation of a switch circuit when a commercial AC power source was cut off to turn on the lamp with DC current.
When a device is connected to a commercial AC power source, AC voltage is generated in the secondary winding 33 and the tertiary winding 34. A DC output is generated between the output terminals of a full-wave rectifier circuit 37, a coil 41 of a relay 40 is excited, and gate current is supplied to a thyrister 45 through resistors 44, 48. As a result, the thyrister 45 is turned on, and charging to a secondary battery starts. When the commercial AC power source is cut off by some reason, the excitation of the coil 41 is released and a coil of a relay 58 is excited by the energy stored in a capacitor 62, a common contact (c) is connected to a usually open contact 58a. Thereby, a lamp 11 is connected to both ends of the secondary battery 2.