Patent ID: 9616605
Date: 2017-04-11
CPC Classifications: B29B,B29C,B30B

Claim:
1. A pellet mill for forming pelleted material, comprising: a die having a cylindrical inner surface with a plurality of apertures formed therein and extending to the outside of the die, the volume bounded by said inner cylindrical surface defining a die chamber, at least two cylindrical rollers adapted to travel over said inner cylindrical surface of the die in a rolling motion, drive means for causing relative rotation of the die and the rollers, so that the rollers will travel over the inner cylindrical surface of the die, thereby forming wedge-shaped spaces between the rollers and the inner cylindrical surface of the die, a feed system, comprising at least two conduits, one associated with each of the at least two rollers, extending into the die chamber, said conduits having a circular cross section, and each comprising a screw conveyor having a shaft tapering in the direction of feed, each of the conduits further having a side opening for feeding the pelletizable material into the wedge- shaped spaces between the rollers and the inner cylindrical surface of the die, the side opening extending axially along the conduit and having an extension that is equal to the length of the rollers, characterized in that at least one of the conduits is configured for expelling the pelletizable material through its side opening in an upward direction directly to a wedge-shaped space, which is at a higher location in the die chamber than said conduit, and in that the screw conveyor comprises a first section comprising a helical screw and a second section comprising a plurality of curved expulsion blades having an increased curvature in the direction towards the helical screw and a length corresponding to the length of the side opening in the conduits.