Sheet conveying apparatus and image forming apparatus

Patent metadata

Field	Value
Publication number	US-9446923-B2
Application number	US-201214349816-A
Country	US
Kind code	B2
Filing date	Dec 4, 2012
Priority date	Dec 9, 2011
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

Provided is a sheet conveying apparatus including: a pair of rollers which includes an upper roller and a lower roller and conveys a sheet in a nipping manner; a driving unit which independently drives the upper roller and the lower roller; a conveying unit which is disposed at the upstream of the pair of rollers in the sheet conveying direction and conveys the sheet to the pair of rollers; an overlapping unit which is provided between the pair of rollers and the conveying unit and overlaps a subsequent sheet on a precedent sheet in the conveying direction; and a control unit which controls the driving unit, wherein the control unit controls the driving unit so that: the upper roller and the lower roller are driven before a leading end of the precedent sheet conveyed by the conveying unit reaches the pair of rollers and the driving of the upper roller and the lower roller is stopped before a tail end of the precedent sheet passes the pair of rollers; the pair of rollers is driven again before a leading end of the subsequent sheet conveyed by the conveying unit and overlapped on the precedent sheet nipped by the pair of rollers reaches the pair of rollers and only the upper roller is driven so as to convey the subsequent sheet to the downstream in the conveying direction after the leading end of the subsequent sheet conveyed by the conveying unit reaches the pair of rollers; and the upper roller and the lower roller are driven so as to convey the precedent sheet and the subsequent sheet overlapped on the precedent sheet to the downstream in the conveying direction.

First claim

The invention claimed is:

1. A sheet conveying apparatus comprising:
a pair of rollers which includes an upper roller and a lower roller and conveys a sheet in a sheet conveying direction and in a nipping manner;
a driving unit which independently drives the upper roller and the lower roller;
a conveying unit which is disposed upstream of the pair of rollers with respect to the sheet conveying direction and conveys the sheet to the pair of rollers;
an overlapping unit which is provided between the pair of rollers and the conveying unit and overlaps a subsequent sheet on a precedent sheet with respect to the sheet conveying direction;
a control unit which controls the driving unit; and
a sheet post-processing unit that includes a stacking portion which temporarily stacks the sheets thereon so as to align the sheets, a reference wall which is provided in the stacking portion as a reference for aligning the sheets in the sheet conveying direction, and an aligning unit which is disposed downstream of the reference wall with respect to the sheet conveying direction, abuts the sheets from an upper side, and conveys the sheets to the reference wall so as to align the sheets,
wherein the pair of rollers is disposed upstream of the sheet post-processing unit with respect to the sheet conveying direction, and
wherein the control unit controls the driving unit so that:
the upper roller and the lower roller are driven before a leading end of the precedent sheet conveyed by the conveying unit reaches the pair of rollers, and the driving of the upper roller and the lower roller is stopped before a tail end of the precedent sheet passes the pair of rollers,
the pair of rollers is driven again before a leading end of the subsequent sheet conveyed by the conveying unit and overlapped on the precedent sheet nipped by the pair of rollers reaches the pair of rollers, and only the upper roller is driven so as to convey the subsequent sheet downstream in the sheet conveying direction after the leading end of the subsequent sheet conveyed by the conveying unit reaches the pair of rollers, and form an overlapping state where the leading end of the subsequent sheet advances by a predetermined amount downstream in the sheet conveying direction from the leading end of the precedent sheet, and
the upper roller and the lower roller are driven so as to convey the precedent sheet and the subsequent sheet overlapped on the precedent sheet downstream in the sheet conveying direction.

2. The sheet conveying apparatus according to claim 1 , further comprising:
a detecting unit which is disposed upstream of the pair of rollers with respect to the sheet conveying direction and which detects the sheets,
wherein the control unit controls the driving unit based on a detection result of the detecting unit.

3. The sheet conveying apparatus according to claim 1 ,
wherein the overlapping unit includes a step which is formed in a conveying path between the conveying unit and the pair of rollers, and
wherein the subsequent sheet conveyed by the conveying unit is overlapped on the precedent sheet on the step.

4. An image forming apparatus comprising:
an image forming unit which forms an image; and
the sheet conveying apparatus according to claim 1 .

5. A sheet conveying apparatus comprising:
a pair of rollers which includes an upper roller and a lower roller and conveys a sheet in a sheet conveying direction and in a nipping manner;
a driving unit which independently drives the upper roller and the lower roller;
a conveying unit which is disposed upstream of the pair of rollers with respect to the sheet conveying direction and conveys the sheet to the pair of rollers;
an overlapping unit which is provided between the pair of rollers and the conveying unit and overlaps a subsequent sheet on a precedent sheet with respect to the sheet conveying direction;
a control unit which controls the driving unit;
a sheet post-processing unit that includes a stacking portion which temporarily stacks the sheets thereon so as to align the sheets, a reference wall which is provided in the stacking portion as a reference for aligning the sheets with respect to the sheet conveying direction, and an aligning unit which is disposed downstream of the reference wall with respect to the sheet conveying direction, moves downward from an upper side so as to abut the sheets, and conveys the sheets to the reference wall so as to align the sheets,
wherein the pair of rollers is disposed upstream of the sheet post-processing unit with respect to the sheet conveying direction,
wherein the control unit controls the driving unit so that:
the upper roller and the lower roller are driven before a leading end of the precedent sheet conveyed by the conveying unit reaches the pair of rollers and the driving of the upper roller and the lower roller is stopped before a tail end of the precedent sheet passes the pair of rollers,
the pair of rollers is driven again before a leading end of the subsequent sheet conveyed by the conveying unit and overlapped on the precedent sheet nipped by the pair of rollers reaches the pair of rollers, and only the upper roller is driven so as to convey the subsequent sheet downstream in the sheet conveying direction after the leading end of the subsequent sheet conveyed by the conveying unit reaches the pair of rollers, and form an overlapping state where the subsequent sheet advances by a predetermined amount downstream in the sheet conveying direction from the precedent sheet, and
the upper roller and the lower roller are driven so as to convey the precedent sheet and the subsequent sheet overlapped on the precedent sheet downstream in the sheet conveying direction.

Assignees

• Canon Kk

Inventors

• Yoshida Masatoshi
• Tsuji Hiroharu
• Koyama Tomooku
• Keino Takuya
• Ochi Junichi

Classifications

• B65H7/06 Primary

  responsive to presence of faulty articles or incorrect separation or feed (B65H7/14 takes precedence) · CPC title

• G03G15/6573

  Feeding path after the fixing point and up to the discharge tray or the finisher, e.g. special treatment of copy material to compensate for effects from the fixing · CPC title

• B65H2511/20

  Location in space · CPC title

• B65H2404/16

  Details of driving · CPC title

• B65H2220/09

  indicating that several of an entity are present · CPC title