Universal ball bearing and movable assembly

The utility model relates to a universal ball bearing and a movable assembly. The universal ball bearing comprises a shaft seat, a universal ball, a ball and a retainer. The retainer is arranged in the rotating groove of the shaft seat, and the balls are arranged in the rolling grooves in the retainer, so that the rolling positions of the balls can be limited by the retainer, the balls cannot be concentrated together when bearing eccentric force, and the relative rolling contact positions of the balls and the universal balls are kept unchanged. Meanwhile, the number of the retainers is at least two, each retainer is provided with a ball, and the retainers can abut against and support different positions of the universal ball through the balls, so that the reliability of supporting and abutting against the universal ball is improved, the friction coefficient of rolling of the universal ball is reduced, the smooth degree of rolling of the universal ball is guaranteed, and the service life of the universal ball