Rotary coupling for lifting hook

The utility model discloses a rotary coupling for a lifting hook, which relates to the field of lifting hooks and comprises a shell and a bearing, the shell is fixedly connected to a lifting frame, an outer ring of the bearing is fixedly connected to the inner wall of the shell, an inner ring of the bearing is fixedly connected with the lifting hook, and the lifting hook is rotatably connected to the shell. A quick locking mechanism is arranged in the shell; the quick locking mechanism comprises a rotating disc, a locking ring, a limiting ring, a large arc block, a small arc block, a U-shaped groove, a limiting groove, a semicircular groove and a semicircular protruding block. By arranging the rotating disc, the locking ring, the limiting ring, the large arc block, the small arc block, the U-shaped groove, the limiting groove, the semicircular groove and the semicircular convex block, the rotating disc is extruded to be close to the bearing by rotating the rotating disc, so that the semicircular convex block