Ball hinge universal shaft assembly

The embodiment of the invention discloses a ball hinge universal shaft assembly, and belongs to the technical field of drilling tools. The ball hinge universal shaft assembly comprises a connector, a hinge shaft, a hinge ball, a first sealing piece, a second sealing piece, an elastic piece and a locking cap. The first end of the hinge shaft extends into the blind hole to form an annular gap, the hinge shaft is sequentially sleeved with the first sealing piece, the second sealing piece, the elastic piece and the locking cap, the locking cap is fixedly connected with the first end of the connector, the first sealing piece, the second sealing piece and the elastic piece are limited in the annular gap, and the elastic piece is clamped between the second sealing piece and the locking cap. The first seal and the second seal can cooperate to seal the annular gap. In the embodiment of the invention, when the first sealing piece and the second sealing piece are abraded, the elastic piece can extrude the second sealing