Cage rib anti-rotation mechanism

The utility model provides a cage rib anti-rotation mechanism which is used for limiting rotation of cage ribs, a plurality of protruding pieces protruding outwards are fixedly arranged at the ends of the cage ribs, the cage rib anti-rotation mechanism comprises a support capable of moving to the ends of the cage ribs, a spring and a check block movably installed on the support, one end of the spring is kept on the support, and the other end of the spring abuts against the check block. The stop block is provided with an anti-rotation limiting part extending out of the support; when the support is moved to the end part of the cage rib, the anti-rotation limiting part of the stop block is embedded between the two adjacent protruding pieces, so that the rotation range of the protruding pieces is limited, the protruding pieces are only allowed to rotate in a certain small angle range, and the cage rib is limited to only rotate in a certain small angle range; therefore, the cage rib is prevented from excessively r