Patent ID: 7896275
Filing Date: 2011-03-01
Classification: B02C

Abstract:
1. A comminution plant for comminuting material and comprising at least one set of fixed bottom knifes separated by openings, at least two parallel shafts extending crosswise of the bottom knifes, a set of upper knifes attached on each shaft, with the upper knifes extending partly into the openings between the bottom knives, and at least one drive assembly for rotating the shafts during operation, wherein the upper knifes on one of the at least two shafts comprise at least one first upper knife having a first diameter and at least one second upper knife having a second diameter which is smaller than the first diameter, that the upper knifes on another of the at least two shafts comprise at least one third upper knife having a third diameter and at least one fourth upper knife having a fourth diameter which is smaller than the third diameter, and that the first diameter and third diameter together are of a size which is larger than twice the distance between the axes of rotation of the at least two shafts, wherein the sum of the sizes of the first diameter and the fourth diameter and of the second diameter and third diameter, respectively, is less than twice the distance between the axes of rotation of the at least two shafts.