Image forming apparatus

Abstract

An image forming apparatus includes a placement portion that include a first surface on which a medium is placed and a protruding portion, a feed roller that opposes the placement portion, a second surface that forms an obtuse angle with the first surface, and a restriction portion disposed downstream of the feed roller in a conveyance direction on the placement portion and that restricts movement of the medium to a predetermined direction. The protruding portion is disposed between the feed roller and the restriction portion.

What is claimed is: 
     
         1 . An image forming apparatus, comprising:
 a placement portion that include a first surface on which a medium is placed and a protruding portion;   a feed roller that opposes the placement portion;   a second surface that forms an obtuse angle with the first surface; and   a restriction portion disposed downstream of the feed roller in a conveyance direction on the placement portion and that restricts movement of the medium to a predetermined direction, wherein   the protruding portion is disposed between the feed roller and the restriction portion.   
     
     
         2 . The image forming apparatus according to  claim 1 , further comprising:
 one or more restriction portions, wherein   the restriction portions comprise supporters that support the medium placed on the placement portion.   
     
     
         3 . The image forming apparatus according to  claim 2 , wherein
 the supporters comprise a first supporter and a second supporter,   a second friction coefficient of the second supporter is larger than a first friction coefficient of the first supporter, and   the protruding portion is disposed between the first supporter and the second supporter.   
     
     
         4 . The image forming apparatus according to  claim 3 , wherein the first friction coefficient is smaller than a friction coefficient of the first surface. 
     
     
         5 . The image forming apparatus according to  claim 3 , wherein the feed roller, the protruding portion, and the second supporter are disposed on one end-part side in a rotational axis direction of the feed roller on the first surface and the second surface. 
     
     
         6 . The image forming apparatus according to  claim 3 , wherein a length of the second supporter from the second surface is greater than a length of the first supporter from the second surface. 
     
     
         7 . The image forming apparatus according to  claim 3 , wherein the second supporter is a friction part mounted on the first supporter. 
     
     
         8 . The image forming apparatus according to  claim 3 , wherein the first supporter and the second supporter are formed from different materials. 
     
     
         9 . The image forming apparatus according to  claim 1 , wherein a length of a region on which the protruding portion is formed on the first surface in a rotational axis direction of the feed roller is at least one third of a length of the feed roller in the rotational axis direction. 
     
     
         10 . The image forming apparatus according to  claim 1 , wherein the protruding portion is disposed within a length of the feed roller in a rotational axis direction of the feed roller. 
     
     
         11 . The image forming apparatus according to  claim 1 , wherein a length of the protruding portion from the first surface is one seventh or more and one fourth or less of a radius of the feed roller. 
     
     
         12 . The image forming apparatus according to  claim 1 , wherein an end part on a feed roller side of the protruding portion is disposed below the feed roller in a direction perpendicular to the first surface. 
     
     
         13 . The image forming apparatus according to  claim 1 , wherein an end part on a feed roller side of the protruding portion is slanted in a direction approaching the first surface as the end part separates from the second surface. 
     
     
         14 . The image forming apparatus according to  claim 1 , wherein the protruding portion contacts the second surface. 
     
     
         15 . The image forming apparatus according to  claim 1 , wherein the protruding portion is separated from the second surface by a predetermined interval. 
     
     
         16 . The image forming apparatus according to  claim 1 , wherein a length of the protruding portion in a rotational axis direction of the feed roller is shorter than half a length of the feed roller in the rotational axis direction. 
     
     
         17 . The image forming apparatus according to  claim 16 , further comprising:
 one or more protruding portions, wherein   the protruding portions are disposed in the rotational axis direction, and   an interval between the protruding portions is a predetermined interval.   
     
     
         18 . The image forming apparatus according to  claim 1 , wherein a length of the protruding portion in a rotational axis direction of the feed roller is greater than or equal to half a length of the feed roller in the rotational axis direction. 
     
     
         19 . The image forming apparatus according to  claim 18 , wherein
 the protruding portions are lined up in the conveyance direction, and   a longitudinal direction of the protruding portions is the rotational axis direction.   
     
     
         20 . The image forming apparatus according to  claim 1 , wherein a corner of the protruding portion is rounded.