Air tightness detection device for box cover

The utility model relates to the technical field of air tightness detection equipment, in particular to an air tightness detection device for a box cover. The device comprises a support and a box cover body, the top of a base is detachably connected with a sealing seat, and the box cover body is inversely arranged on the sealing seat; a jacking mechanism and an airtightness detection mechanism are arranged at the top of the fixing plate, the jacking mechanism comprises an air cylinder arranged at the top of the fixing plate, the end of a piston rod of the air cylinder penetrates through the fixing plate and is connected with a top plate, and a plurality of jacking assemblies are distributed at the bottom of the top plate at intervals; the air tightness detection mechanism comprises a first air pipe and a pressure reducing valve arranged on the first air pipe, the first air pipe is connected with a second air pipe and a third air pipe through a three-way connector, the second air pipe is provided with a first