Sheet stacking apparatus and bookmaking apparatus using the same

Abstract

A sheet stacking apparatus includes a tray for sequentially stacking sheets from a discharge path. The tray including a fixed support member, a movable support member, and a drive device disposed on the moveable support member. The drive device moves the movable support member to allow the movable support device to support different sheet position according to a length of the sheet in a conveyance direction.

1 . A sheet stacking apparatus comprising: 
 a discharge path configured to convey out a sheet;    tray means for sequentially stacking the sheet from the discharge path, the tray means further comprising a fixed support member configured to support a side edge of a sheet in a conveyance direction and a movable support member configured to support the other side edge of the sheet and movable in the conveyance direction; and    drive means for moving the movable support member so that the movable support member supports different positions of the sheet according to a length of the sheet in the conveyance direction.    
     
     
         2 . The sheet stacking apparatus according to  claim 1 , wherein 
 the fixed support member and the movable support member for forming the tray means are configured such that the fixed support member is disposed at an upstream side of a sheet discharge direction from the discharge path and the movable support member is disposed at a downstream side of the sheet discharge direction;    the drive means is operable to move the movable support member to a position to bend a sheet by operation of a leading edge of the sheet hanging downward and outside the tray.    
     
     
         3 . The sheet stacking apparatus according to  claim 1 , further comprising aligning means including paired left and right aligning members configured to engage right and left sides of a sheet stacked in the tray means; and 
 a movable aligning member operably connected to at least one of the paired right and left aligning members, the moveable aligning member operable to move in a width direction orthogonal to the conveyance direction of the sheet.    
     
     
         4 . The sheet stacking apparatus according to  claim 3 , wherein:  
       the aligning means are arranged above the fixed support member forming the tray means, 
 the drive means is configured to move the movable support member to a position to bend a sheet by operation of a leading edge of the sheet hanging downward and outside the tray, and the movable aligning member is configured to move in a width direction of the sheet in order to engage the bent sheet.  
 
     
     
         5 . The sheet stacking apparatus according to  claim 1 , wherein the movable support member comprises a sheet pressing member configured to engagingly press an uppermost stacked sheet, the sheet pressing member being movable along the sheet conveyance direction above the movable support member and comprising pressing position movement means for varying a position in order to touch a sheet according to a length of the sheet in the conveyance direction.  
     
     
         6 . The sheet stacking apparatus according to  claim 3 , further comprising: 
 auxiliary conveyance means disposed above the fixed support member for conveying the sheet from the discharge path to a predetermined position of the fixed support member; wherein the auxiliary conveyance means is configured to move between a position operable to touch the sheet on the fixed support member and a position retracted thereabove; and    wherein the auxiliary conveyance means includes elevator shifting means for retracting to the retracted position when the aligning members move the sheet in a width direction.    
     
     
         7 . The sheet stacking apparatus according to  claim 6 , wherein the auxiliary conveyance means further comprises: forward and reverse-rotating rollers operable to rotate in the sheet conveyance direction in order to convey the sheet to a predetermined position of the fixed support member; and guide members operable to guide the sheet from the discharge path to a predetermined position of the fixed support member.  
     
     
         8 . The sheet stacking apparatus according to  claim 1 , wherein the fixed support member forming the tray means includes:  
       controlling means comprising at least one side for controlling a position of an edge of the sheet in the conveyance direction; and  
       auxiliary conveyance means for conveying the uppermost sheet on the fixed support member; 
 wherein the fixed support member is obliquely arranged to move the sheet to the controlling means; and wherein the drive means is operable to move the movable support means to the controlling means.  
 
     
     
         9 . A sheet stacking apparatus comprising: 
 a discharge path configured to sequentially convey a sheet from a discharge outlet;    tray means configured below the discharge path for sequentially stacking the sheet, the tray means including a length in a conveyance direction shorter than a minimum-sized sheet, a fixed support member operable to support a trailing edge of the sheet in the conveyance direction, a movable support member configured to support a leading edge of the sheet and move in the conveyance direction, and drive means for varying a sheet support position according to a length of the sheet in the conveyance direction, wherein the tray means is further configured so that the leading edge of the sheet hangs down and outward from the tray;    aligning means for aligning a width direction orthogonal to the conveyance direction on the tray means;    auxiliary conveyance means arranged above the tray means for turning over the sheet in the conveyance direction and conveying the sheet to a predetermined position on the tray means; and    wherein the auxiliary conveyance means and the aligning means are arranged on the fixed support member of the tray means;    wherein the auxiliary conveyance means are operable to move between an acting position engaging the sheet, and a retracted position retracted from the sheet; and    wherein the auxiliary conveyance means are held at the retracted position when the aligning means are moving in a sheet width direction.    
     
     
         10 . A bookmaking system comprising: 
 a discharge path including a discharge outlet configured to sequentially convey a sheet out from an image forming apparatus;    tray means arranged below the discharge path for sequentially stacking the sheet from the discharge outlet;    a binding processing position comprising binding means for a bookmaking process;    bundle conveyance means for conveying the sheet bundle from the tray means to the binding processing position;    and storing stacking means for storing sheets bound by the bookmaking process;    wherein the tray means comprises a fixed support member operable to support a trailing edge of the sheet in a conveyance direction, a movable support member operable to support a leading edge of the sheet moving along the conveyance direction, and drive means disposed on the movable support means for varying a sheet support position according to a length direction of the sheet in the conveyance direction.    
     
     
         11 . The bookmaking apparatus according to  claim 10 , further comprising:  
       auxiliary conveyance means for conveying the sheet from the discharge path to a predetermined position on the tray means, the auxiliary conveyance means being arranged to move between a position touching the sheet on the fixed support member and a position retracted thereabove; and 
 aligning means for aligning an edge of a stacked sheet to a reference position, the aligning means including a left and right pair of aligning members operable to engage a right side and a left side of the sheet on the fixed support member, at least one of the aligning members further comprising a movable aligning member operable to move in a width direction that is orthogonal to the conveyance direction of the sheet.