Building intelligent fire alarm device

The utility model discloses an intelligent building fire alarm device, which belongs to the technical field of fire alarm, and comprises a positioning plate and a protective shell arranged below the positioning plate, the bottom of the positioning plate is fixedly connected with a connecting sleeve, the outer wall of the connecting sleeve is slidably connected with an adjusting ring, the outer wall of the connecting sleeve is symmetrically provided with two through holes, and the adjusting ring is slidably connected with the positioning plate. A pushing column is slidably connected into a through hole of the connecting sleeve, a fixing block is fixedly connected to the end face, located in the connecting sleeve, of the pushing column, a supporting spring is fixedly connected between the connecting sleeve and the fixing block, guide grooves allowing the pushing column to move are formed in the inner walls of the two sides of the adjusting ring, and the protective shell is inserted into the connecting sleeve. T