Ball nut, ball connector assembly and vehicle

The utility model relates to a car lamp connecting piece, and discloses a ball head nut which is used for connecting a ball head screw and a part to be connected, a mounting hole for the ball head nut to be inserted is formed in the part to be connected, the ball head nut comprises a ball socket part and a mounting part, and the ball socket part forms a hollow cylinder structure with one end being an open end; cantilever structures and connecting columns which are evenly distributed in the circumferential direction are arranged on the peripheral face of the ball socket part, a gap is formed between the outer diameter of the end, away from the open end of the ball socket part, of each cantilever structure and the corresponding mounting hole, a limiting protruding part is arranged on or integrally formed on the peripheral face of the end, away from the open end of the ball socket part, of each connecting column, and the limiting protruding parts are in interference fit with the mounting holes. In addition, the