The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 06, 1999
Filed:
Feb. 14, 1996
Applicant:
Inventor:
Aarne Laatikainen, Valko, FI;
Assignee:
Sunds Defibrator Loviisa Oy, Valko, FI;
Primary Examiner:
Int. Cl.
CPC ...
B07B / ;
U.S. Cl.
CPC ...
209 44 ; 209673 ;
Abstract
The invention relates to a method and apparatus for screening pulverized or chip material, such as fibers or wood chips, free from impurities. The material to be screened is fed onto a roll set formed by a number of adjacent, essentially parallel rolls (1) and is brought to an advantageous movement with the help of the rolls (1), whereby material particles of highest density drift downward closest to the surfaces of the rolls and that the material fraction closest to the roll surfaces can escape the rolls via a gap (B) a width essentially larger than the gap width (A) of the preceding roll pairs.