Medium discharge device and image reading apparatus

Abstract

A medium discharge device includes a discharge roller pair that discharges a medium and a discharged-medium placement unit that includes a placement surface on which the medium being discharged is placed. The discharge roller pair is configured to change a discharge angle of the medium in a discharge angle, the medium being discharged from the discharge roller pair, the discharged-medium placement unit is configured to change a placement angle of the placement surface in the discharge direction, and at least one of the discharge angle and the placement angle is changed in accordance with a discharge speed of the medium being discharged from the discharge roller pair.

What is claimed is: 
     
         1 . A medium discharge device comprising:
 a discharge roller pair that discharge a medium; and   a discharged-medium placement unit including a placement surface at which the medium being discharged is placed, wherein   the discharge roller pair is configured to change a discharge angle of the medium in a discharge angle, the medium being discharged from the discharge roller pair,   the discharged-medium placement unit is configured to change a placement angle of the placement surface in the discharge direction, and   at least one of the discharge angle and the placement angle is changed in accordance with a discharge speed of the medium being discharged from the discharge roller pair.   
     
     
         2 . A medium discharge device according to  claim 1 , comprising:
 a discharge angle change unit configured to change the discharge angle, wherein   the discharge angle change unit moves a second roller with respect to a first roller along a circumferential surface of the first roller to change a nipping position between the first roller and the second roller, the first roller being one of the discharge roller pair, the second roller being the other one thereof.   
     
     
         3 . A medium discharge device according to  claim 1 , comprising:
 a placement angle change unit configured to change the placement angle, wherein   the placement angle change unit vertically moves a downstream end of the placement surface in the discharge direction with an upstream end of the placement surface in the discharge direction as a starting point.   
     
     
         4 . A medium discharge device according to  claim 1 , wherein
 the discharge angle and the placement angle are changed by a single driving unit.   
     
     
         5 . A medium discharge device according to  claim 1 , comprising:
 a discharge angle change unit configured to change the discharge angle;   a placement angle change unit configured to change the placement angle;   a first driving unit configured to drive the discharge angle change unit;   a second driving unit configured to drive the placement angle change unit; and   a control unit, wherein   the control unit is configured to drive the first driving unit, based on first data, to change the discharge angle, drive the second driving unit, based on second data, to change the placement angle, and change the discharge angle and the placement angle, based on third data,   the first data is set as an appropriate range of the discharge angle with respect to the discharge speed of the medium,   the second data is set as an appropriate range of the placement angle with respect to the discharge speed of the medium, and   the third data is set as an appropriate range of the discharge angle and the placement angle with respect to the discharge speed of the medium.   
     
     
         6 . A medium discharge device according to  claim 1 , wherein
 at least one of the discharge angle and the placement angle is changed in accordance with a basis weight of the basis weight of the medium.   
     
     
         7 . An image reading apparatus comprising:
 the medium discharge device according to  claim 1 ; and   a reading unit being positioned upstream of the medium discharge device and being configured to read the medium being transported.