Paper sheet feeding apparatus

Abstract

A paper sheet feeding apparatus according to an embodiment includes a first feeding tray 210, a pickup unit 150, a second feeding tray 310, an air blow unit 130, a status sensor 140, and a controller 100. The first feeding tray 210 and the second feeding tray 310 respectively feed a batch of sheets to the pickup unit 150. The air blow unit 130 blows air to loosen an upper part of the batch of sheets. The status sensor 140 detects sparseness value of the upper part of the batch of sheets. The controller 100 makes the batch of sheets on the first feeding tray 210 to fall on top of that of the second feeding tray 310 when switching the feeding tray in charge of feeding the sheets from the first feeding tray 210 to the second feeding tray 310.

What is claimed is: 
     
         1 . A paper sheet feeding apparatus, comprising:
 a first feeding tray configured to support and feed a batch of sheets, said first feeding tray movable in a vertical direction;   a second feeding tray configured to support and feed a batch of sheets, said second feeding tray movable in a vertical direction;   a pickup unit configured to pick up sheets, arranged above the first feeding tray or the second feeding tray in charge of feeding;   an air blow unit configured to blow air towards an upper part of the batch of sheets on the first feeding tray or the second feeding tray in charge of feeding from a side of the upper part of the batch of sheets;   a status sensor configured to detect a sparseness value of the upper part of the batch of sheets loosened by the air blow unit; and   a controller configured to control the vertical movement of the first feeding tray or the second feeding tray in charge of feeding so that the sparseness value of the upper part of the batch of sheets stays within an upper limit sparseness value and a lower limit sparseness value that is suitable for picking up a sheet from the batch of sheets;   wherein the first feeding tray is movable in a direction perpendicular to the vertical direction after making the first feeding tray ascend until the status sensor detects the upper limit sparseness value, such that the batch of sheets on the first feeding tray falls on top of the batch of sheets on the second feeding tray.   
     
     
         2 . A paper sheet feeding apparatus according to  claim 1 ,
 wherein the controller is configured to move the first feeding tray in the perpendicular direction so that a distance d is greater than a margin D,   wherein the distance d is a distance between a position of the first feeding tray when reaching the upper limit sparseness value and a position of the first feeding tray when reaching the lower limit sparseness value, and   wherein the margin D is a distance the batch of sheets on the first feeding tray falls on top of the batch of sheets on the second feeding tray when the first feeding tray moves perpendicularly from the vertical direction.   
     
     
         3 . A paper sheet feeding apparatus according to  claim 2 ,
 wherein the controller elevates the second feeding tray while moving the first feeding tray perpendicularly from the vertical direction.   
     
     
         4 . A paper sheet feeding apparatus according to  claim 1 ,
 wherein the first feeding tray and the second feeding tray configure a meshing structure in a plane perpendicular to the vertical direction; and   wherein the controller moves the first feeding tray downwards below the second feeding tray after the first feeding tray is moved perpendicularly from the vertical direction, and then elevates the first feeding tray to a common plane as the second feeding tray such that the batch of sheets on the second feeding tray is transferred to the first feeding tray.   
     
     
         5 . A paper sheet feeding apparatus according to  claim 2 ,
 wherein the first feeding tray and the second feeding tray configure a meshing structure in a plane perpendicular to the vertical direction; and   wherein the controller moves the first feeding tray downwards below the second feeding tray after the first feeding tray is moved perpendicularly from the vertical direction, and then elevates the first feeding tray to a common plane as the second feeding tray such that the batch of sheets on the second feeding tray is transferred to the first feeding tray.   
     
     
         6 . A paper sheet feeding apparatus according to  claim 3 ,
 wherein the first feeding tray and the second feeding tray configure a meshing structure in a plane perpendicular to the vertical direction; and   wherein the controller moves the first feeding tray downwards below the second feeding tray after the first feeding tray is moved perpendicularly from the vertical direction, and then elevates the first feeding tray to a common plane as the second feeding tray such that the batch of sheets on the second feeding tray is transferred to the first feeding tray.   
     
     
         7 . A paper sheet feeding apparatus according to  claim 1 ,
 wherein the controller elevates the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the lower limit sparseness value, and stops the elevation of the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the upper limit sparseness value.   
     
     
         8 . A paper sheet feeding apparatus according to  claim 2 ,
 wherein the controller elevates the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the lower limit sparseness value, and stops the elevation of the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the upper limit sparseness value.   
     
     
         9 . A paper sheet feeding apparatus according to  claim 3 ,
 wherein the controller elevates the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the lower limit sparseness value, and stops the elevation of the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the upper limit sparseness value.   
     
     
         10 . A paper sheet feeding apparatus according to  claim 4 ,
 wherein the controller elevates the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the lower limit sparseness value, and stops the elevation of the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the upper limit sparseness value.   
     
     
         11 . A paper sheet feeding apparatus according to  claim 5 ,
 wherein the controller elevates the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the lower limit sparseness value, and stops the elevation of the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the upper limit sparseness value.   
     
     
         12 . A paper sheet feeding apparatus according to  claim 6 ,
 wherein the controller elevates the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the lower limit sparseness value, and stops the elevation of the first feeding tray or the second feeding tray in charge of feeding when the status sensor detects the upper limit sparseness value.