Emergency lighting device

Abstract

Abstract PURPOSE:To obtain light required for long hours by the use of a storage battery with small capacity, by controlling a continuity pulse width of a lighting control transistor so that constant lamp power is supplied to an incandescent lamp and that a luminous flux of the lamp is made to become a prescribed value. CONSTITUTION:A lighting control transistor Q1 is interposed between a storage battery BT and an incandescent lamp LP, and the transistor Q1 is held on an off state by a power-off detection circuit DT at the normal time of a commercial power source AC, and the off state of the transistor Q1 is released at the power-off time of the commercial power source AC. A continuity pulse width of the transistor Q1 is controlled by a controlling circuit CT so that constant lamp power is supplied to the incandescent lamp LP and that a luminous flux of the lamp LP is made to become a prescribed value. Accordingly the lighting and putting out control of the lamp LP and the luminous flux control of the lamp LP can be performed by using only a single lighting control transistor Q1. Hence, the lamp LP can be lighted with required light for long hours by using a storage battery BT with small capacity.

Inventors

• 👤 Seiji Soga
• 👤 Seiji Hamahata

Bibliographic Details