Centering cutting assembly

The utility model discloses a centering cutting assembly which comprises a left slotting assembly and a right slotting assembly, the left slotting assembly and the right slotting assembly are symmetrically installed on the two sides of a middle frame assembly in a left-right mode respectively, the left slotting assembly and the right slotting assembly each comprise a slotting blade and a pressing wheel set, the number of the slotting blades is two, and the number of the pressing wheel sets is two. The blade frame is connected to a middle connecting rod horizontally hinged to the middle of the parallelogram mechanism in parallel in a telescopic mode through a blade telescopic mechanism, and the pressing wheel set is rotationally connected to the roller frame. The roller frame is fixedly connected to a top connecting rod hinged to the top of the parallelogram mechanism through a base plate cantilever and keeps in the same direction with the slotting blade, a side connecting rod of the parallelogram mechanism is