Papermaking strainer, foreign material separation apparatus for papermaking, and manufacturing method of papermaking strainer

Abstract

A papermaking strainer disposed adjacent to a rotor, for sieving a disintegrated paper material, includes a strainer for facing the rotor, including a plurality of strainer holes formed in the strainer; and a plurality of peripheral walls protruding from a surface of the strainer to surround the plurality of strainer holes, or a plurality of peripheral concaved groove portions concaved from the surface of the strainer to surround the plurality of strainer holes.

What is claimed is: 
     
         1 . A papermaking strainer disposed in proximity to a rotating rotor, for sieving a disintegrated paper material, comprising:
 a strainer adapted to be disposed adjacent to the rotor, and having a plurality of strainer holes passing therethrough; and   a plurality of peripheral walls protruding from a surface of the strainer to surround the plurality of strainer holes, or a plurality of peripheral concaved groove portions concaved inwardly from the surface of the strainer to surround the plurality of strainer holes.   
     
     
         2 . A papermaking strainer according to  claim 1 , wherein each peripheral wall of the plurality of peripheral walls or each peripheral concaved groove portion of the plurality of peripheral concaved groove portions surrounds a periphery of each strainer hole or some strainer holes of the plurality of strainer holes. 
     
     
         3 . A papermaking strainer according to  claim 1 , wherein the plurality of peripheral walls or the plurality of peripheral concaved groove portions has an annular shape, and
 the plurality of strainer holes is formed not only inside the peripheral walls or the peripheral concaved groove portions but outside the peripheral walls or the peripheral concaved groove portions.   
     
     
         4 . A foreign material separation apparatus for papermaking, comprising:
 a separator adapted to be disposed adjacent to a rotor, and having a plurality of holes for separating a paper material passing through the plurality of holes from a foreign material not passing through the plurality of holes; and   a plurality of peripheral walls protruding from a surface of the separator to surround the holes of the separator; or a plurality of peripheral concaved groove portions concaved from the surface of the separator to surround the holes of the separator.   
     
     
         5 . A foreign material separation apparatus for papermaking according to  claim 4 , wherein the plurality of peripheral walls is formed from a material having a hardness greater than that of the separator,
 each peripheral wall of the plurality of peripheral walls surrounds a periphery of each hole or some holes of the plurality of holes, and   the plurality of peripheral walls is formed.   
     
     
         6 . A manufacturing method of a papermaking strainer, comprising:
 a boring step for boring a plurality of strainer holes in a strainer; and   a peripheral-wall forming step, after the boring step, for forming a plurality of peripheral walls protruding from a surface of the strainer to surround at least one periphery of the plurality of strainer holes, wherein the plurality of peripheral walls is formed from a material having a hardness greater than that of the strainer around the strainer holes.   
     
     
         7 . A manufacturing method of a papermaking strainer, comprising:
 a peripheral-wall forming step for forming a plurality of peripheral walls protruding from a surface of a strainer wherein the plurality of peripheral walls is formed from a material having a hardness greater than that of the strainer; and   a boring step, after the peripheral-wall forming step, for boring at least one strainer hole in the strainer inside the plurality of peripheral walls while avoiding boring the peripheral walls on the surface of the strainer.