Cam and connecting rod combined duckbilled opening and closing mechanism

The invention relates to the technical field of agricultural machinery, and particularly discloses a cam and connecting rod combined duckbilled opening and closing mechanism. Comprising a duckbilled assembly and a cam, a connecting rod assembly is arranged on a seeding roller, the contour surface of the cam is composed of sine acceleration cambered surfaces on the two sides and an arc surface in the middle, the connecting rod assembly comprises a deflector rod connected with the duckbilled assembly and a direct-acting piece acting with the cam, and an elastic piece is arranged between the deflector rod and the seeding roller. One end of the direct-acting piece is connected with the driving lever through a pin-groove pair, and the other end of the direct-acting piece acts on the contour surface of the cam; the cam connecting rod combined duckbilled opening and closing mechanism ensures stable seeding of the seeding roller, the duckbilled opening and closing mechanism keeps the maximum opening state for unearth