Square magnetic ring with different poles

The utility model discloses a square magnetic ring with different poles in the technical field of magnetic rings, which comprises an outer ring and an inner ring, the inner ring is a two-half circular arc ring, the outer ring is a circular hole square ring formed by two half C-shaped rings, an outer expansion ring is fixedly connected outside the circular arc ring, a concave ring is arranged in the C-shaped ring, the outer expansion ring is matched with the concave ring, one end of the C-shaped ring is fixedly connected with a fixing hook, and the other end of the C-shaped ring is fixedly connected with the fixing hook. A locking cavity is formed in the other end of the fixing hook, a fixing plate is arranged in the locking cavity, fixing claws are connected to the two ends of the fixing plate, a closing plate is slidably connected to the inner side of the end of each fixing claw, a guide cut corner is formed in the side, facing outwards, of the bottom end of each closing plate, and the fixing hook enters the