Sheet manufacturing apparatus

Abstract

A sheet manufacturing apparatus includes a defibrating unit that generates a defibrated material, a web forming unit that generates a web, a supply pipe that supplies a mixture together with air, and a sheet forming unit that presses the web to generate a sheet, the supply pipe is provided with a first rectifying plate having a substantially trapezoidal shape and extending in a supply direction of the mixture, and the first rectifying plate has a first base angle formed by a lower base in contact with an internal wall of the supply pipe and a first leg located upstream in the supply direction, the first base angle being 25° or more and less than 45°, and a second base angle formed by the lower base and a second leg located downstream in the supply direction, the second base angle being 55° or more and less than 85°.

What is claimed is: 
     
         1 . A sheet manufacturing apparatus comprising:
 a defibrating unit that defibrates a raw material to generate a material containing fibers;   a web forming unit that accumulates the material to generate a web;   a supply pipe that supplies the material from the defibrating unit to the web forming unit together with air; and   a forming unit that presses the web generated by the web forming unit to generate a sheet, wherein   the supply pipe includes an inner wall provided with a first rectifying plate having a substantially trapezoidal shape and extending in a supply direction of the material, and   the first rectifying plate has a first base angle formed by a lower base in contact with the inner wall of the supply pipe and a first leg located upstream in the supply direction, the first base angle being 25° or more and less than 45°, and a second base angle formed by the lower base and a second leg located downstream in the supply direction, the second base angle being 55° or more and less than 85°.   
     
     
         2 . The sheet manufacturing apparatus according to  claim 1 , wherein
 the first base angle is 25° or more and less than 35°.   
     
     
         3 . The sheet manufacturing apparatus according to  claim 1 , wherein
 the second base angle is 55° or more and less than 65°.   
     
     
         4 . The sheet manufacturing apparatus according to  claim 1 , wherein
 the inner wall of the supply pipe is provided with a second rectifying plate having a substantially trapezoidal shape and extending in the supply direction of the material, and   the first rectifying plate and the second rectifying plate are disposed such that upper bases thereof face each other.   
     
     
         5 . The sheet manufacturing apparatus according to  claim 4 , wherein
 an interval between the upper base of the first rectifying plate and the upper base of the second rectifying plate is 20 mm or more.   
     
     
         6 . The sheet manufacturing apparatus according to  claim 1 , wherein
 the first rectifying plate is disposed in a linear first pipe of the supply pipe, and a length of the lower base is ½ or more and ⅔ or less of a length of the first pipe.   
     
     
         7 . The sheet manufacturing apparatus according to  claim 1 , further comprising
 a mixing unit that is provided between the defibrating unit and the supply pipe and mixes a binder for binding the fibers to each other with the material.