| 摘要 |
PURPOSE:To make an elevator operatable even in power failure, by connecting a DC output obtained through rectification of AC power supply in parallel to a power supply comprising diodes connected in series to a battery and automatically supply electric power from the battery during power failure. CONSTITUTION:When an AC power supply 1 is in normal operation, power is supplied to an electric motor 7 via a rectifier 2, a capacitor 3 and an inverter 4 and to a control circuit 20 and a brake 9 via a transformer 15 a rectifier 16, a capacitor 17 and a converter 19. Simultaneously, reverse voltage is applied to diodes 30, 31 and an electric charger 14 charges a battery 13. Hereat, if AC power supply 1 fails, electric power is automatically supplied from the battery 13 to the motor 7 via the diode 30 and to the control circuit 20 and the brake 9 via the diode 31. In this case, the speed reference of the motor 7 is limited and set up by a battery voltage detected by a detector 32 or DC power supply voltage of an inverter bridge 4. Thus, running to the closes story can be continued without any shock in case of power failure. |
