Novel alarm device

The utility model relates to the field of building electrical technology, in particular to a novel alarm device. The quick mounting device comprises a base and a transparent protective cover, the transparent protective cover is assembled on one side of the base, a quick mounting mechanism is assembled on the other side of the base, and a protective mechanism is assembled between the base and the transparent protective cover. The quick mounting mechanism comprises a first semicircular seat, a first U-shaped frame, a first cylindrical rod, a threaded rod, a nut, a second U-shaped frame, a second cylindrical rod, a boss, a second semicircular seat and a third U-shaped frame. Through the structural design of the quick mounting mechanism, the device can be automatically mounted without other tools, the mounting and dismounting work efficiency of the device is improved, and through the structural design of the protection mechanism, the device can protect the alarm device and prevent the alarm device from being acci