EMERGENCY LAMP

摘要

PURPOSE:To prevent degradation of service life and leakage of liquid of battery due to over discharge by providing an over discharge preventing function. CONSTITUTION:A battery 1 and a lamp 2 are connected in series and the lamp 2 is ON/OFF controlled through a switching element 3. A switching control circuit 4 controls the switching element 3 so that the switching element 3 is latched when the voltage of the battery 1 drops below a predetermined level while the switching element 3 is latched off for the battery voltage drop of shorter duration than the delay time of a delay element. The battery 1 is charged by a commercial power source 7 through a rectifying/smoothing circuit 8 and a charging circuit 9.