Pin shaft

The invention relates to a pin shaft. The pin shaft comprises a cylindrical body, an expanding sleeve and a fixing part. The peripheral wall at one end of the body is provided with a first slope surface, and the distance from the first slope surface to an axis of the body is gradually decreased along the direction departing from the other end of the body. The expanding sleeve comprises a sleeve body sleeving one end of the body, the inner peripheral wall of the sleeve body is provided with a second slope surface in abutting joint with and matched with the first slope surface, and the sleeve body is provided with at least one slit penetrating the sleeve body radially and extending towards two ends of the sleeve body. The fixing part is used for applying axial pressure, towards the body, on the expanding sleeve so as to enable the sleeve body to be expanded open by the first slope surface. The pin shaft is capable of eliminating gaps between pin shaft holes of hinge joint seats and the pin shaft, so that service life of the pin shaft is prolonged and connection precision of the pin shaft is improved.