Four-ledge zigzag dynamic variable-gap internal mixer rotor

The invention discloses a four-ledge zigzag dynamic variable-gap internal mixer rotor. The internal mixer rotor comprises a rotor body, wherein four ledges are arranged on the rotor body and comprise two long ledges and two short ledges; the ledges spirally extend from two ends of the rotor body to the middle of the rotor body; each ledge comprises an initial end and a tail end; a plurality of tooth grooves are formed in the top of each ledge; widths of the tooth grooves of each ledge are not changed in the direction from the initial end to the tail end; and distances among the tooth grooves are gradually reduced. The four-ledge zigzag dynamic variable-gap internal mixer rotor has the beneficial effects that the tooth grooves are formed in the ledges of the internal mixer rotor, circumferential flowing of rubber is changed, and distributing and dispersing of various packing and ingredients are facilitated; and the number and the distribution density of the tooth grooves are increased along with increasing of circumferential flowing speed of the rubber, the effect of mutual kneading of the lump-shaped rubber among the ledges is improved, so that flowing of the rubber in a mixing chamber is disordered, and rubber mixing quality and rubber mixing efficiency are improved.