| 摘要 |
<p>The invention concerns a sifting procedure intended for treating materials difficult to sift, in which any one component of the material tends to become adherent to the surface of the sieve, and a sifting apparatus for applying such a procedure. An example of said materials difficult to sift is the mixture consisting of sunflower seeds and of other kinds of inflorescence material accompanying them, which is produced in connection with harvesting these seeds. The adhesion problem has been solved in the invention by using a brush roll (3) disposed against the surface of the sieve (2), in the manner that the brush roll is rotated about its own axis (4) and, at the same time, the surface of the sieve and the brush roll are displaced in relation to each other. Hereby the brush roll (3) sets the material to be sifted in motion and, on the side, detaches material that has become adherent to the surface so that the sieve is kept permeable. The sieve may consist of a rotating drum sieve (2) against the inner surface of which the brush roll (3) is mounted. To the purpose of moving the material to be sifted, introduced at one end of the drum sieve (2), during the sifting process towards the opposite end of the sieve, the brush roll (3) may be provided with a helical thread (7) moving the material to be sifted.</p> |
