Capsule type sealing structure self-adaptive to pressure

The invention relates to the technical field of medical instruments, in particular to a pressure self-adaptive capsule type sealing structure which comprises an outer sheath, an upper cover covering the top end of the outer sheath and a self-adaptive sealing ring mounted between the outer sheath and the upper cover, and the self-adaptive sealing ring comprises a sealing plate with a cross opening in the center and a capsule fixed to the top end of the sealing plate. The outer ring of the bag body is fixed on the periphery of the sealing plate, the inner ring of the bag body is fixed on the periphery of the cross-shaped opening, a closed cavity is formed between the bag body and the sealing plate, at least two through holes are formed in the sealing plate below the cavity, the bag body encloses towards the center to form a swim ring-shaped opening, and the swim ring-shaped opening is located right above the cross-shaped opening; by means of the self-adaptive pressure bag type sealing structure, the blood leaka