Self-adaptive lower pressing head for shaft part straightening machine

The invention discloses a self-adaptive lower pressing head for a shaft part straightening machine. The self-adaptive lower pressing head comprises an upper cover plate, a self-locking device, a buffering device, a universal joint, a positioning pin and a lower bottom plate. The upper cover plate is connected with the lower bottom plate through a positioning spring; the self-locking device is connected with the positioning pin through a supporting ball table and a supporting connecting rod in the universal joint; the upper part of the buffer device is connected with the tail part of the upper cover plate through a sleeve, and the tail part is tangent to the circular truncated cone transition curved surface on the lower bottom plate; the supporting connecting rod is hinged with the mounting positioning boss on the lower bottom plate through the positioning pin; and the lower surface of the lower bottom plate is wavy, two sides of the lower bottom plate are symmetrically raised, and the middle of the lower bott