QUICK CHARGING CIRCUIT OF NO-BREAK POWER UNIT

PURPOSE:To miniaturize a device economically and enable the device to be quickly charged, by using the primary side voltage of a transformer at the time of commercial conduction, and by forming the charging circuit of a battery. CONSTITUTION:At the time of commercial conduction, an AC switch ACSWO is in an ON-state, and by a charging circuit RF, a battery E is charged to be kept. When the voltage of the battery E is low, then to the primary side P of a main transformer T, the commercial voltage ep of the main transformer T according to a turn ratio is applied, and so when the commercial voltage ep is higher than the sum of the forward voltage drop component of a thyristor THY 1 or THY 2 and the voltage Vo of the battery E, then charging current is fed to the battery E, also from the thyristors THY 1 and THY 2 and a rectifier circuit due to the main transformer T. When the battery E is set in a filled-up state, then current flowing through the main transformer T is not generated in the battery E.