Vertical pressing device of cutting machine

The invention discloses a vertical pressing device of a cutting machine. The vertical pressing device of the cutting machine comprises a crane sliding rail installed on a crane supporting frame, a sensing device is fixed to the bottom end of the crane supporting frame and connected with an air cylinder switch through a wire, a four-connecting-rod mechanism with a roller wheel supporting frame fixed to the bottom end is fixed to the crane supporting frame through a hinge, and an air cylinder is fixed to the crane supporting frame and makes contact with the four-connecting-rod mechanism. One end of a pull spring is fixed to the crane supporting frame, the other end of the pull spring is connected with the four-connecting-rod mechanism, a check ring for a hole is fixed to one side of a roller wheel arranged on a roller wheel shaft, a bearing end cover is arranged on the other side of the roller wheel, and check rings for shafts are arranged at the two ends of the roller wheel shaft respectively. The vertical pre