Multi-cutterhead vertical straw smashing and returning machine

The utility model discloses a multi-cutterhead vertical straw smashing and returning machine in the technical field of agricultural machinery, which comprises a frame, a transmission system, a suspension mechanism, a support mechanism and a cutterhead assembly, and the frame is composed of an upper guard plate, side guard plates, a bottom guard plate, spacing plates and frame rods. Three transmission gear box installation holes with the same size are formed in the middle of the upper protection plate, an impurity discharging opening is formed in the side face protection plate, the transmission system is composed of a main transmission gear box, a secondary transmission gear box and a belt, and the main transmission gear box and the secondary transmission gear box are connected through the belt. The cutter head assembly is composed of a cutter head fixing plate, a cutter head connecting pipe, movable cutters and an air plate, the movable cutters are fixed to the cutter head fixing plate through bolts, and the