Alarm convenient to overhaul

The utility model discloses an alarm convenient to overhaul in the technical field of alarms, which comprises a fixing plate, a connecting shell arranged at the bottom of the fixing plate, an alarm outer shell arranged at the bottom of the connecting shell, an external thread arranged at the bottom of the outer wall of the connecting shell, and an internal thread arranged at the top of an inner cavity of the alarm outer shell and matched with the external thread. An electrical component mounting plate is arranged at the bottom of an inner cavity of the alarm shell, connecting blocks are arranged in the middles of the front and rear end faces of the electrical component mounting plate, and clamping blocks are arranged at the ends, away from the electrical component mounting plate, of the connecting blocks; the connecting shell and the alarm outer shell are movably connected through the matched external threads and internal threads, so that a worker can disassemble the alarm outer shell from the bottom of the c