Medium separating and supplying mechanism

Abstract

The present invention provides a medium separating and supplying mechanism that may reduce the causes of jams and errors on a conveyance path and so forth from supply onward. Namely, by making the skew angle of a medium less than a limit angle θmax, at which skewing is regard to increase, when the medium reaches a gate portion, the present invention may prevent the medium from rotating at an overlap point in a direction in which the skew angle is increased, which occurs as a result of the medium reaching the overlap point.

1 . A medium separating and supplying mechanism comprising:
 a side surface guide having paper sheet mediums stacked inside;   a pickup roller that supplies the mediums stacked inside the side surface guide;   a gate portion including a separation feed roller and a separation gate roller that are arranged on a downstream side of the pickup roller in a supply direction in which the mediums are supplied, form an overlap portion as a result of channels and ridges disposed in their outer peripheral surfaces overlapping one another, hold in the overlap portion the mediums supplied by the pickup roller, and separate and supply the mediums one item at a time;   supply feed rollers that supply the mediums that have been separated one item at a time in the gate portion; and   supply rollers that are arranged touching the supply feed rollers on the downstream side of the gate portion in the supply direction and hold and supply the mediums at contact points where the supply rollers touch the supply feed rollers,   wherein the medium separating and supplying mechanism is configured such that the skew angle, with respect to a width direction orthogonal to the supply direction, of the mediums reaching the gate portion becomes smaller than a limit angle formed by a straight line that joins a contact point farthest from the center in the width direction and a point, nearest to the contact point, of the overlapping channels and ridges in the gate portion farthest from that contact point and a straight line that is parallel to the width direction.   
     
     
         2 . The medium separating and supplying mechanism according to  claim 1 , wherein supply direction and width direction lengths of the side surface guide are determined such that the skew angle, with respect to the width direction, of the mediums reaching the gate portion becomes smaller than the limit angle. 
     
     
         3 . The medium separating and supplying mechanism according to  claim 1 , wherein the supply feed rollers and the supply rollers that are farthest from the center in the width direction are disposed nearer to the center so that the limit angle becomes larger. 
     
     
         4 . The medium separating and supplying mechanism according to  claim 1 , wherein in the gate portion, the number of channels and ridges disposed on the outer peripheral surfaces of the separation feed roller and the separation gate roller is few so that the limit angle becomes larger.