The magnetic stripe attracts unevenly. When the steel plate is lifted by suction, the original four magnetic strips can't contact and press the surface of the lifted steel plate at the same time, resulting in a great impact between the steel plate and the magnetic strips, which affects the lifting ability, which is caused by the uneven suction of the magnetic strips. The hard connection between the four scattered magnetic strips and the upper balance hanging beam is changed into the soft connection of chain connection. When the four magnetic strips are in contact with the steel plate, the shape of the steel plate can be self-adaptive and the suction force is balanced, thus ensuring the lifting ability of the magnetic sucker.