Internal and external corner detection device with corner leveling mechanism for decoration engineering

The utility model relates to the technical field of decoration engineering, and discloses an internal and external corner detection device with a corner leveling mechanism for decoration engineering, which comprises a main ruler and an auxiliary ruler, the auxiliary ruler is movably arranged in the main ruler, the lower end of the main ruler is provided with a leveling unit, and the leveling unit comprises a push plate and a leveling plate A fixedly arranged on one side of the push plate. A sliding block is arranged at the lower end of the pushing plate, a ball is arranged at the lower end of the sliding block, the pushing plate is installed in a sliding groove A in the lower end of the main ruler through the sliding block arranged at the lower end of the pushing plate, and the leveling plate A is flush with the side face of the main ruler. The leveling unit and the auxiliary plate are arranged at the lower ends of the main ruler and the auxiliary ruler, after the leveling unit and the auxiliary plate are pla