A processing apparatus comprises: a conveyance part for conveying a sheet; a processing part including a processing member that is installed in a manner of being movable in an intersecting direction of intersecting with a conveyance direction of the conveyance part and that performs predetermined processing at a predetermined position of the sheet under conveyance; a stacker part for accumulating processing articles obtained by the processing of the processing part; and a control part for controlling the stacker part such as to sort a predetermined amount of precedently ejected ones of the processing articles from the subsequent ones of the processing articles among the processing articles ejected to the stacker part by the conveyance part.

Disclosed is a post-processing apparatus couplable to an image forming apparatus. The post-processing apparatus comprises: a paper discharging roller to convey, from a conveying path, a first paper discharged from the image forming apparatus, to a standby path connected to the conveying path, and convey the first paper from the standby path and a second paper discharged from the image forming apparatus from the conveying path, to an intermediate loading part, in a state in which a leading end of the first paper toward the intermediate loading part protrudes more than a leading end of the second paper toward the intermediate loading part to process the first paper and the second paper.

According to one embodiment, a sheet separator has a first driving roller and a pressing body. The first driving roller rotates about a first rotation shaft. The first driving roller conveys a sheet bundle including a plurality of sheets. The pressing body is capable of approaching the first driving roller. The first driving roller is rotatable in a first direction with the sheet bundle sandwiched between the first driving roller and the pressing body. The pressing body pivots in the first direction about the first rotation shaft with the sheet bundle sandwiched between the first driving roller and the pressing body to cause the plurality of sheets to deviate from one another at edges.

A post-processing apparatus for post-processing paper discharged from an image forming apparatus comprises: a paper discharging roller for conveying both first and second paper sequentially discharged from an image forming apparatus to an intermediate loading part; a main paddle part for conveying the first and second paper loaded on the intermediate loading part to a compiling region; a reverse roller for conveying, together with the main paddle part, the first and second paper to the compiling region; and a binding part for processing the first and second paper conveyed to the compiling region, the paper discharging roller allows the first paper to stand by on a standby path, and conveys the first and second paper to the intermediate loading part in a state in which the leading end of the first paper protrudes further than the leading end of the second paper.

According to an embodiment, a sheet processing apparatus includes a transport unit and a holding unit. The transport unit transports a first sheet to a first position. The transport unit transports a second sheet, which is transported after the first sheet, to a second position displaced to the upstream side of a sheet transport direction relative to the first position. The transport unit transports a third sheet, which is transported after the second sheet, to a third position displaced to the downstream side of the sheet transport direction relative to the second position. In the case where the second sheet is transported to the second position, the holding unit holds the first sheet at the first position. In the case where the third sheet is transported to the third position, the holding unit holds the second sheet at the second position.

The sheet stacker includes a sheet conveyor arrangement, configured for feeding a plurality of sheets and having a sheet discharge end, and a stacking bay. In the stacking bay sheets delivered by the sheet conveyor arrangement are formed into stacks. A stack conveyor is provided in the stacking bay and is movable in a conveyor direction parallel to a sheet feeding direction, according to which the sheets are fed from the sheet discharge end onto the stack conveyor. The sheet discharge end is configured and controlled such that it is gradually lifted during sheet stacking, in order to accommodate a growing stack of sheets being formed on the stack conveyor. A stop plate is positioned in the stacking bay above the stack conveyor and in front of the sheet discharge end of the sheet conveyor arrangement. The stop plate is configured and controlled to be gradually lifted from the stack conveyor as the sheet stack grows, to be withdrawn upon completion of the stack thus allowing removal of the stack in an evacuation direction substantially parallel to the conveyor direction, and to be lowered towards the stack conveyor again.

A sheet stacker includes a sheet conveyor arrangement and a stacker platform. The sheets are fed in a sheet feeding direction on the stacker platform, to form stacks of sheets thereon. The stacker platform supports a stack conveyor configured and controlled to move in a conveyor direction to move the stack under formation such that sequentially piled up jobs are placed in an approximately centered position one with respect to the other according to the sheet feeding direction.

According to one embodiment, a sheet separator has a first driving roller and a pressing body. The first driving roller rotates about a first rotation shaft. The first driving roller conveys a sheet bundle including a plurality of sheets. The pressing body is capable of approaching the first driving roller. The first driving roller is rotatable in a first direction with the sheet bundle sandwiched between the first driving roller and the pressing body. The pressing body pivots in the first direction about the first rotation shaft with the sheet bundle sandwiched between the first driving roller and the pressing body to cause the plurality of sheets to deviate from one another at edges.

A buffer means includes a buffer unit that makes paper sheets temporarily stand by and a paper stacking unit that intermittently conveys paper sheets and sucks the trailing edges of the paper sheets to stack the paper sheets stepwise and make them temporarily stand by.

Disclosed herein is a sheet processing apparatus comprising a sheet tray configured to hold a bundle composed of the sheets fed from conveyance rollers, a wait path configured to keep waiting following sheets upstream the conveyance rollers, an accumulating tray configured to hold a sheet bundle, delivery rollers configured to nip the sheet bundle mounted on the sheet tray and the following sheets, to set off from one another, and to deliver them to the accumulating tray, and to switch back the following sheets to the sheet tray, and a conveyance member configured to convey the following sheets from the sheet tray.