SIMPLE FIRE ALARM

PROBLEM TO BE SOLVED: To enable a handicapped person or an aged person also to simply replace a battery when power supply voltage is dropped by fitting a simple fire alarm near the ceiling of a room and storing a battery in a storing box fitted to the sidewall of the room. SOLUTION: Power is always supplied from the battery 5 stored in the storing box 4 to an electronic circuit in the simple fire alarm 3 fitted to the ceiling 1 through a cord 6. When a comparatively long period has elapsed from the installation of the fire alarm 3, the voltage of the battery 5 is dropped in proportion to the time elapsed. When the voltage of the battery 5 is dropped, a voltage drop alarm circuit warns the necessity of substitution of the battery 5 by the intermittent ringing of a buzzer or the flashing of an LED. The preparation of a stepladder or a stool is not required at all for the replacement of the battery 5. The battery 5 can be replaced by opening the open/close cover of the storing box 4 fitted to the sidewall 2 near to the floor of the room and replacing the battery 5 held on a battery holder. Thus the replacement of the battery 5 can be extremely easily executed in the room.