U.S. patent application number 12/193931 was filed with the patent office on 2009-08-27 for sheet collecting device, post-processing apparatus and image forming apparatus.
This patent application is currently assigned to Konica Minolta Business Technologies, Inc.. Invention is credited to Tsutomu Anezaki, Masato Hizuma, Tomohiko Kiryu, Tsuyoshi Mizubata, Satoru SHIMIZU, Ryohei Sunayama, Mikihiro Yamakawa.
Application Number | 20090212485 12/193931 |
Document ID | / |
Family ID | 40997531 |
Filed Date | 2009-08-27 |
United States Patent
Application |
20090212485 |
Kind Code |
A1 |
SHIMIZU; Satoru ; et
al. |
August 27, 2009 |
SHEET COLLECTING DEVICE, POST-PROCESSING APPARATUS AND IMAGE
FORMING APPARATUS
Abstract
Providing a sheet collecting device capable of being downsized
and of operating stably wherein a sheet ejecting device that
conveys and ejects a sheet in the direction for making the sheet
fall along a slanted sheet collecting board is provided, and a
leading edge stopper that holds sheets on the sheet collecting
board is set so that a trailing edge of the sheet may be at a
constant height independently of a sheet size.
Inventors: |
SHIMIZU; Satoru; (Tokyo,
JP) ; Mizubata; Tsuyoshi; (Tokyo, JP) ; Kiryu;
Tomohiko; (Tokyo, JP) ; Yamakawa; Mikihiro;
(Tokorozawa-shi, JP) ; Anezaki; Tsutomu; (Tokyo,
JP) ; Hizuma; Masato; (Tokyo, JP) ; Sunayama;
Ryohei; (Tokyo, JP) |
Correspondence
Address: |
FRISHAUF, HOLTZ, GOODMAN & CHICK, PC
220 Fifth Avenue, 16TH Floor
NEW YORK
NY
10001-7708
US
|
Assignee: |
Konica Minolta Business
Technologies, Inc.
Tokyo
JP
|
Family ID: |
40997531 |
Appl. No.: |
12/193931 |
Filed: |
August 19, 2008 |
Current U.S.
Class: |
271/213 |
Current CPC
Class: |
B65H 2801/27 20130101;
B65H 2511/20 20130101; B65H 31/02 20130101; B65H 2511/11 20130101;
B65H 2405/221 20130101; B65H 2511/414 20130101; B65H 2511/11
20130101; B65H 2220/01 20130101; B65H 2511/20 20130101; B65H
2220/02 20130101; B65H 2220/11 20130101; B65H 2511/414 20130101;
B65H 2220/01 20130101 |
Class at
Publication: |
271/213 |
International
Class: |
B65H 31/04 20060101
B65H031/04 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 22, 2008 |
JP |
JP2008-041346 |
Claims
1. A sheet collecting device comprising: a sheet collecting board
including a sheet supporting surface which is inclined so that an
upstream side thereof in a sheet conveyance direction when a sheet
is carried in is higher than a downstream side thereof; an ejecting
device which is positioned upstream of the sheet collecting board
and which ejects the sheet on the sheet collecting board by
conveying the sheet in a direction so that the sheet falls along
the sheet collecting board; a leading edge stopper which stops the
sheet on the sheet collecting board; a stopper moving device which
changes a position of the leading edge stopper; and a control
device which controls the stopper moving device so that a position
of a trailing edge of the sheet when the sheet is carried in on the
sheet collecting board is constant regardless of a difference of a
size of the sheet.
2. The sheet collecting device of claim 1, wherein the control
device controls the stopper moving device based on sheet size
information.
3. The sheet collecting device of claim 1, wherein the ejecting
device has an ejection exit for ejecting the sheet and the position
of the trailing edge of the sheet on the sheet collecting board is
lower than a position of the ejection exit.
4. A post-processing apparatus comprising: the sheet collecting
device of claim 1; a stapler which staples sheets on the sheet
collecting board, the sheets having been collected on the sheet
collecting board, wherein the control device controls the stopper
moving device so as to move and set the leading edge stopper at a
second stop position after setting the leading edge stopper at a
first stop position for collecting the sheets and wherein the
stapler staples the sheets supported by the leading edge stopper
set at the second stop position.
5. A post-processing apparatus comprising: the sheet collecting
device of claim 1; a folding device which folds the sheet having
been collected on the sheet collecting board, wherein the control
device controls the stopper moving device so as to move and set the
leading edge stopper at a third stop position after setting the
leading edge stopper at a first stop position for collecting the
sheet and wherein the folding device folds the sheet supported by
the leading edge stopper set at the third stop position.
6. The post-processing apparatus of claim 4 comprising: a gripping
member which grips the sheets, wherein when the leading edge
stopper moves while supporting the sheets, the control device
controls the stopper moving device and the gripping member so that
the leading edge stopper moves after the gripping member grips the
sheets.
7. The post-processing apparatus of claim 5 comprising: a gripping
member which grips the sheet, wherein when the leading edge stopper
moves while supporting the sheet, the control device controls the
stopper moving device and the gripping member so that the leading
edge stopper moves after the gripping member grips the sheet.
8. An image forming apparatus comprising: an image forming
apparatus main body which forms an image on a sheet; and the sheet
collecting device of claim 1 which collects the sheet on which the
image is formed by the image forming apparatus main body.
Description
[0001] This application is based on Japanese Patent Application No.
2008-041346 filed on Feb. 22, 2008 in Japanese Patent Office, the
entire content of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to improvement of a sheet
collecting device which is provided on an image forming apparatus
or on a post-processing apparatus.
[0003] A stapler that binds a plurality of sheets generally has a
sheet collecting board on which plural sheets are stacked, and it
conducts stitching process for sheets stacked on the sheet
collecting board.
[0004] A folding device that folds therein a center portion of a
sheet also has a sheet collecting board, and it conducts folding
process for sheets stacked on the sheet collecting board.
[0005] In a technology disclosed in Unexamined Japanese Patent
Application Publication No. 2000-63031, a sheet collecting board
(compile tray) is provided, and a sheet is caused to go up above
the sheet collecting board by conveyance by a sheet ejection
device, and the sheet released from the sheet ejection device falls
on the sheet collecting board to be stopped at a prescribed
position on the sheet collecting board.
[0006] Then, by repeating these operations, a plurality of sheets
are stacked on the sheet collecting board.
[0007] In a technology disclosed in Unexamined Japanese Patent
Application Publication No. 2000-63031, a leading edge (trailing
edge in the case of carrying-in) of a sheet is stopped at a fixed
position or at a position for saddle stitching or center
folding.
[0008] In Unexamined Japanese Patent Application Publication No.
11-322163, there is disclosed a sheet processing device wherein
plural sheets are stacked on a slanted sheet collecting board
(vertical path) by repeating sheet conveyance in which a sheet is
supplied to the vertical path and the sheet is dropped along the
vertical path to be stopped by a stopper, and thereby, the stacked
sheets are stitched.
[0009] In Unexamined Japanese Patent Application Publication No.
11-322163, when stacking sheets which are ejected continuously, a
trailing edge (upper end) of the precedent sheet hits a leading
edge (lower end). Therefore, to avoid this problem, a position of a
sheet ejection exit of a sheet ejection device is switched by use
of a flapper.
[0010] In the case of sheet ejection by a sheet ejection device in
Unexamined Japanese Patent Application Publication No. 2000-63031
wherein a sheet is caused to rise above a collecting board, and a
sheet released from a sheet ejection device is allowed to fall on
the sheet collecting board to be stacked on a prescribed position,
a space for securing a conveyance path for switchback of a sheet is
required, resulting in a problem that a size of the apparatus is
increased.
[0011] There is also a problem that high-speed conveyance becomes
difficult, because switchback of a sheet makes a conveyance time
per one sheet longer.
[0012] In a sheet processing device wherein sheets in various sizes
are stacked on the sheet collecting board through switching of
sheet ejection exits by using a flapper, like the device disclosed
in Unexamined Japanese Patent Application Publication No.
11-322163, a mechanism is complicated and operations are not
stabilized to cause conveyance troubles easily, because a
conveyance path switching mechanism is needed.
[0013] Further, in the case of sheet sizes wherein a difference of
the length is small, there is a problem that coping with various
sizes is difficult, because switching conveyance paths is
difficult.
SUMMARY
[0014] The aforesaid problems are solved by the following
embodiments of the invention. [0015] 1. A sheet collecting device
having therein a sheet collecting board that has a sheet supporting
surface which is slanted so that the upstream side thereof in the
sheet conveyance direction in the case of sheet carrying-in is
higher than the downstream side, an ejecting device that is
arranged upstream of the sheet collecting board, and that conveys a
sheet in a direction so that the sheet falls along the sheet
collecting board to be ejected onto the sheet collecting board, a
leading edge stopper that stops the sheet on the sheet collecting
board, a stopper moving device that changes the position of the
aforesaid leading edge stopper and a control device that controls
the stopper moving device, wherein the control device controls the
stopper moving device so that the trailing edge of the sheet in the
case of sheet carrying-in on the sheet collecting board is at a
fixed position regardless of a sheet size difference. [0016] 2. A
post-processing apparatus having therein the sheet collecting
device described in the aforesaid Item 1 and a stapler that
conducts a stitching process on the sheet collecting board for
sheets stacked on the aforesaid sheet collecting board, wherein the
aforesaid control device controls the stopper moving device to set
the leading edge stopper at the first stop position for sheet
collecting, and then, to move the leading edge stopper to be set at
the second stop position, and the aforesaid stapler conducts the
stitching process for the sheets supported by the leading edge
topper that is set at the second stop position. [0017] 3. A
post-processing apparatus having therein the sheet collecting
device described in the aforesaid Item 1 and a folding device that
conducts a folding process for sheets collected on the sheet
collecting board, wherein the aforesaid control device controls the
stopper moving device to set the leading edge stopper at the first
stop position for sheet collecting, and then, to move the leading
edge stopper to be set at the third stop position, and the
aforesaid folding device conducts the folding process for the
sheets supported by the leading edge stopper that is set at the
third stop position. [0018] 4. An image forming apparatus that has
the sheet collecting device described in the aforesaid Item 1.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 shows an overall view of an image forming apparatus
relating to an embodiment of the invention.
[0020] FIG. 2 is a diagram showing a sheet collecting device
relating to an embodiment of the invention.
[0021] FIG. 3 is a diagram showing a sheet carry-in section of a
sheet collecting device.
[0022] FIG. 4 is a block diagram of a control system of a
post-processing apparatus relating to Embodiment 1 of the
invention.
[0023] FIG. 5 is a flow chart of operations of a post-processing
apparatus in saddle stitching/center folding.
[0024] FIG. 6 is a block diagram of a control system of a
post-processing apparatus relating to Embodiment 1 of the
invention.
[0025] FIG. 7 is a flow chart of operations of a post-processing
apparatus in side stitching.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0026] The invention will be described as follows, referring to the
illustrated embodiments to which, however, the invention is not
limited.
<Image Forming Apparatus>
[0027] FIG. 1 is an overall view of an image forming apparatus
relating to an embodiment of the invention equipped with image
forming apparatus main body A and post-processing apparatus FS.
[0028] Illustrated image forming apparatus main body A is equipped
with image reading section 1, image processing section 2, image
writing section 3, image forming section 4, sheet-feeding cassette
5, sheet-feeding device 6, fixing unit 7, sheet discharge section 8
and automatic two-sided copying sheet-feeding section (ADU) 9.
[0029] On the upper part of the image forming apparatus main body
A, there is mounted automatic document feeding device DF. The
post-processing apparatus FS is connected on the illustrated left
side of the image forming apparatus main body A, that is, the sheet
discharge section 8 side.
[0030] A document placed on a document stand of automatic document
feeding device DF is conveyed in the direction of an arrow, and
images on one side or on two sides of the document are read by an
optical system of image reading section 1 and further read into CCD
image sensor 1A.
[0031] Analog signals which have been converted photoelectically by
CCD image sensor 1A are subjected to analog processing, A/D
conversion, shading correction and image compression in image
processing section 2, and then, are sent to image writing section
3.
[0032] When forming images, output light is emitted from a
semiconductor laser of image writing section 3, to irradiate
photoconductor drum 4A of image forming section 4, so that a latent
image is formed on the photoconductor drum 4A. In the image forming
section 4, processes such as charging, exposure, developing,
transfer, separation and cleaning are conducted. Recording sheet S1
fed by sheet-feeding device 6 from sheet-feeding cassette 5 comes
in contact with the photoconductor drum 4A on which the latent
image is made to be a toner image through developing process, and
the toner image is transferred by transfer device 4B onto the
recording sheet S1. The recording sheet S1 carrying the toner image
is subjected to fixing by fixing unit 7, and is fed into
post-processing apparatus FS from sheet discharge section 8. In the
case of two-side copying, the recording sheet S1 whose one side has
been finished in terms of image processing is fed into automatic
two-side copying sheet feeding section 9 through conveyance path
switching plate 8A, and is subjected to image processing on its
reverse side in image forming section 4 to be discharged from sheet
discharge section 8 after being fixed.
[0033] Next, a post-processing apparatus relating to an embodiment
of the invention will be described, referring to FIG. 1.
[0034] Post-processing apparatus FS has therein sheet carry-in
section 20, insertion sheet feeding sections 30a and 30b and a
plurality of post-processing sections. The post-processing section
has therein punching process section 40, folding process section
50, superposing process section 60, staplers 71 and 103 and sheet
discharge section 80.
[0035] Insertion sheet S2 is loaded in insertion sheet feeding
section 30a, and another insertion sheet S3 is loaded in insertion
sheet feeding section 30b.
[0036] Insertion sheets S2 and S3 are sheets to be inserted in
recording sheet S1 discharged from image forming apparatus main
body A, such as a cover sheet and an inserted sheet, and they can
be subjected to punching process and folding process in the same
way as recording sheet S1.
[0037] Inserted sheets S2 and S3 fed out of insertion sheet feeding
sections 30a and 30b are conveyed to sheet carry-in section 20
through a conveyance path running downward (having no reference
symbol).
[0038] Punching process section 40 is arranged on sheet carry-in
section 20.
[0039] Meanwhile, in the description hereafter, recording sheet S1,
insertion sheets S2 and S3 are given a generic name of sheet S.
[0040] Folding process section 50 is arranged on conveyance path H1
that is branched downward from sheet carry-in section 20.
[0041] Superposing process section 60 is arranged at downstream
side of conveyance path H2 that is branched upward from sheet
carry-in section 20, and is equipped with conveyance paths H3, H4
and H5.
[0042] The superposing process section 60 causes succeeding sheet S
to stand by at conveyance path H4 and conveyance paths H3 and H5 to
secure a period of time for preceding sheet S to conduct stitching
process in stapler 71 located on the downstream side.
[0043] The conveyance path positioned at the downstream side of
conveyance path H2 is branched into conveyance paths which are
curved doubly as inside conveyance path H4 and outside conveyance
paths H3 and H5.
[0044] On an exit of conveyance path H4 that is branched from
conveyance path H2 to form a curved inside conveyance path, there
is provided conveyance roller 21. When the first sheet of sheets S
to be stitched is conveyed there, the conveyance roller 21 is at
standstill and stops a leading edge of the first sheet. It causes
the first sheet to stand by under the condition that the first
sheet is in contact with conveyance roller 21.
[0045] Sheet S conveyed through conveyance path H4 stands by under
the state where its leading edge is stopped by conveyance roller 21
as stated above, while, a succeeding sheet S enters conveyance path
H3 from conveyance path H2 and arrives at the conveyance roller
21.
[0046] From the conveyance roller 21, preceding sheet S and
succeeding sheet S are conveyed together under the state where both
sheets S are superposed, and are conveyed to collecting section
70.
[0047] Conveyance path H3 is connected with conveyance path H2 at
the downstream side of the conveyance path H2, and conveyance path
H5 is connected with conveyance path H3.
[0048] The conveyance path H3 is branched into conveyance path H5
and conveyance path H6.
[0049] Conveyance path H6 forms a sheet discharge path through
which sheet S is discharged to fixed sheet discharge tray 81.
[0050] Fixed sheet discharge tray 81 is arranged at a position so
as to be protruded from post-processing apparatus FS that is at the
downstream side of conveyance path H6 branched from superposing
process section 60 at conveyance rollers 24 on conveyance path
H3.
[0051] As stated above, sheet S conveyed through conveyance paths
H2, H3 and H6 and discharged is stacked on the fixed sheet
discharge tray 81.
[0052] Sheet discharge section 80 has sheet discharge roller 22,
and discharges sheet S on elevating sheet discharge tray 82.
[0053] The sheet discharge rollers 22 are composed of a pair of
rollers, and in the case of non-sheet-discharge, the paired rollers
stay apart from each other, while, in the case of sheet discharge,
the paired rollers come in contact with each other to nip and
convey sheet S to discharge it on the elevating sheet discharge
tray 82.
[0054] Sheet S conveyed by conveyance roller 21 travels in the
direction toward a left side between a pair of rollers 22 which
stay away from each other, and when a trailing edge of the sheet S
leaves the conveyance roller 21, the sheet S falls on collecting
section 70 to slide down its slope, and it is caught by a stopper
(not shown) to stop on the collecting section 70.
[0055] After the set number of sheets S have been stacked on the
collecting section 70, stapler 71 operates to stitch the sheets
S.
[0056] The sheets S thus stitched are lifted up by the aforesaid
stopper, and move on the collecting section 70 toward a left
side.
[0057] In this case, a pair of rollers constituting the sheet
discharge rollers 22 come in contact with each other to nip and
convey sheet S to discharge it on the elevating sheet discharge
tray 82.
[0058] In the folding mode, sheet S is conveyed downward through
conveyance path H1 from sheet carry-in section 20, and then, is
subjected to center folding or folding into three in folding
process section 50, and is discharged to lower sheet discharge tray
83.
[0059] In the saddle stitching mode, sheet S is conveyed downward
through conveyance path H1 from sheet carry-in section 20. The
sheet S is subjected to saddle-stitching process in stapler 103 and
is discharged to lower sheet discharge tray 83 after being
subjected to center folding process in folding process section
50.
[0060] Sheet discharge paths for sheet S include the following four
paths; [0061] 1) sheet carry-in section 20.fwdarw.conveyance path
H2.fwdarw.conveyance path H3.fwdarw.conveyance path H6.fwdarw.fixed
sheet discharge tray 81 [0062] 2) sheet carry-in section
20.fwdarw.conveyance path H2.fwdarw.conveyance paths H3, H4 and
H5.fwdarw.collecting section 70.fwdarw.sheet discharge section
80.fwdarw.elevating sheet discharge tray 82 [0063] 3) sheet
carry-in section 20.fwdarw.conveyance path
H2.fwdarw.H4.fwdarw.sheet discharge section 80.fwdarw.elevating
sheet discharge tray 82 [0064] 4) sheet carry-in section
20.fwdarw.conveyance path H1.fwdarw.folding process section
50.fwdarw.lower sheet discharge tray 83
[0065] Paths 1), 2) and 4) are those described above.
[0066] Path 3) is selected when forming a large amount of images
without conducting stitching process and folding process.
[0067] Sheet S is discharged on elevating sheet discharge tray 82
without any post processing, and the elevating sheet discharge tray
82 moves downward as shown by chain lines in FIG. 1 so that the
uppermost surface of discharged sheets S may be always at the
constant height.
[0068] Therefore, several thousand sheets may be stacked on the
elevating sheet discharge tray 82.
<Sheet Collecting Device>
[0069] A sheet collecting device relating to Embodiment 1 of the
invention will be described as follows, referring to FIGS. 2 and
3.
[0070] FIG. 2 is a diagram showing a sheet collecting device
relating to an embodiment of the invention, and FIG. 3 is a diagram
showing a sheet carry-in section of a sheet collecting device.
[0071] The numeral 100 represents an intermediate stack tray that
is a sheet collecting board supporting sheets S to be stitched or
folded, 101 represents a guide that constitutes conveyance path H1
in FIG. 1, 102 represents a conveyance roller that forms a lower
end of a sheet ejection section which ejects a sheet to
intermediate stack tray 100, 103 represents a stapler that conducts
stitching process for sheets S, 104 represents an aligning member
that aligns sheets S in their width direction (direction
perpendicular to the conveyance direction), 105 represents a
leading edge stopper that stops sheet S having been conveyed and
that supports sheet S on intermediate stack tray 100, 106
represents an gripping member that grips sheet S, 52 represents a
folding plate, and 53-55 represent folding rollers. The folding
rollers 53-55 constitute a folding process section 50.
[0072] The intermediate stack tray 100 is provided below conveyance
path H1 as is illustrated.
[0073] Further, the intermediate stack tray 100 is provided to be
inclined so that a downstream side in the conveyance direction may
be positioned to be lower and an upstream side may be positioned to
be upper, thus, sheet S ejected on the intermediate stack tray 100
slides down along the intermediate stack tray 100 and is caught by
the leading edge stopper 105 to be stopped.
[0074] The stapler 103 conducts stitching operations to staple
sheets on the intermediate stack tray 100.
[0075] The aligning member 104 is driven by motor M2 to be
reciprocated in the width direction that is perpendicular to the
conveyance direction of sheet S, to align edges of sheets S in the
width direction.
[0076] The leading edge stopper 105 is driven by motor M1
representing a stopper moving device to move in the sheet
conveyance direction, and is set at the position corresponding to a
sheet size.
[0077] A position for the leading edge stopper 105 to be set at
will be described as follows, referring to FIG. 3.
[0078] Sheet S conveyed by conveyance roller 102 that serves as an
ejecting device that ejects sheet S to the intermediate stack tray
100 falls at the moment when it leaves conveyance rollers 102 that
forms an ejection exit through which the sheet is ejected, and it
is caught by the leading edge stopper 105 to be placed on the
intermediate stack tray 100.
[0079] The leading edge stopper 105 is set so that the sheet S may
stop after the trailing edge leaves conveyance roller 102
surely.
[0080] The leading edge stopper 105 is driven by motor M1 to move
to be set so that trailing edge position H2 of sheet S that is
placed on the intermediate stack tray 100 may be always at a
constant height, even in the case where sheets S each having a
different size are conveyed.
[0081] A plurality of sheets S are placed on the intermediate stack
tray 100 and when plural sheets are placed, succeeding sheet S is
supplied to the intermediate stack tray 100 under the state where
preceding sheet S exists on the intermediate stack tray 100.
[0082] In this case, it is necessary to set the position of the
leading edge stopper 105 so that a trailing edge of carry-in (upper
end) of the preceding sheet may not hit a leading edge of carry-in
(lower end) of the succeeding sheet.
[0083] The leading edge of the succeeding sheet is ejected along a
path shown with chain line L1 from conveyance roller 102.
[0084] Path L1 is determined by a shape of a conveyance path
although it may be slightly changed depending on properties of
sheet S, and it does not take a position that is higher than the
upper limit leading edge landing point shown by landing position
height H3 where the Leading edge of sheet S lands on the
intermediate stack tray 100.
[0085] The upper limit of height H3 of the landing position is
determined, in a design stage of the device, by a sheet-feeding
test wherein the maximum thickness of sheets S stacked on the
intermediate stack tray 100 is estimated.
[0086] By setting the leading edge stopper 105 so that height H2 of
a position of a trailing edge of sheet S on the intermediate stack
tray 100 may be higher than height H3 of a landing position, sheets
S supplied continuously on the intermediate stack tray 100 are
stacked on the intermediate stack tray 100 smoothly, without any
collision between respective sheets.
[0087] As described above, when the position of the leading edge
stopper 105 is set so that height H2 of a trailing edge of sheet S
stacked on the intermediate stack tray 100 may be lower than the
lower bottom (ejection exit) of conveyance roller 102 that forms a
lower end of a sheet ejection section of conveyance path Hi, and
height H2 of a trailing edge of sheet S may be higher than height
H3 of a landing position of sheet S, sheets S supplied continuously
on the intermediate stack tray 100 are stacked smoothly.
[0088] When sheets S of the set quantity are stacked on the
intermediate stack tray 100, gripping member 106 rotates in the
direction of arrow W1 to grip sheet S. In this case, the gripping
member 106 moves together with leading edge stopper 105.
[0089] The gripping member 106 is driven by solenoid SL to rotate
in the direction of arrow W1, and grips sheet S between the
intermediate stack tray 100 and the gripping member 106.
[0090] In the processing of saddle stitching for a plurality of
sheets S, leading edge stopper 105 is set to the position where a
center line of sheet S in its conveyance direction agrees with a
stapling position of stapler 103, under the state where sheet S is
gripped by gripping member 106.
[0091] Under this state, a stitching process is conducted by
stapler 103.
[0092] Folding process section 50 has folding plate 52 and folding
rollers 53, 54 and 55.
[0093] In center folding process, leading edge stopper 105 is set
to the position where a center line of sheet S agrees with a middle
position between folding roller 53 and folding roller 54. Under
this condition, when folding plate 52 enters a space between
folding roller 53 and folding roller 54, then, sheet S is inserted
in a space between both rollers 53 and 54, and when folding rollers
53 and 54 are rotated under the condition that sheet S is inserted,
the sheet S is conveyed while it is subjected to the folding
process.
[0094] A processing apparatus that conducts folding process by
using folding plate and three folding rollers 53-55 is widely
known, and for example, those disclosed in Unexamined Japanese
Patent Application Publication No. 2006-56669 can be used.
[0095] As stated above, leading edge stopper 105 moves to the first
stop position that is a position for stacking sheets S, the second
stop position for a stitching process and to the third stop
position for a folding process, and as is shown with dotted lines
in FIG. 2, the leading edge stopper 105 and the gripping member 106
move unitedly when they move between the aforesaid plural stop
positions.
[0096] Operations of the post-processing apparatus with the
aforesaid structure will be described as follows, referring to
FIGS. 4-6.
[0097] FIG. 4 is a block diagram of a control system of a
post-processing apparatus relating to Embodiment 1 of the
invention, FIG. 5 is a flow chart of operations of a
post-processing apparatus in saddle stitching-center folding and
FIG. 7 is a flow chart of operations of a post-processing apparatus
in side stitching.
[0098] In FIG. 4, the numeral 200 represents a control device
provided on post-processing apparatus FS, and 201 represents a main
control device that is provided on an image forming apparatus main
body and controls an overall image forming apparatus.
[0099] The control device 200 controls post-processing apparatus FS
shown in FIG. 1.
[0100] In step ST1 sheet size information, namely, size information
such as A4 size and B4 size are acquired from the main control
device 201. Meanwhile, this size information includes information
of longitudinal feeding (conveyance wherein a length in a width
direction is of the long side) and information of lateral feeding
(conveyance wherein a length in a conveyance direction is of the
long side).
[0101] In step ST2, motor M1 operates, and leading edge stopper 105
moves to the first stop position.
[0102] The first stop position is a position where sheet S is
supported so that the trailing edge of sheet S on intermediate
stack tray 100 in the case of carry-in in all sheet sizes may be at
the height shown by H2 in FIG. 3.
[0103] Sheets S of the set quantity are supplied to intermediate
stack tray 100 while leading edge stopper 105 is set to the first
stop position.
[0104] Sheet alignment in step ST3 means operations wherein the
aligning member 104 is driven by motor M2 to be reciprocated in the
width direction, and this sheet alignment is carried out every time
each sheet S is supplied.
[0105] When sheets S of the set quantity have been stacked,
solenoid SL operates in step ST4 to rotate gripping member 106,
whereby, edges of sheets S are gripped.
[0106] Next, in step ST5, a judgment is made whether the mode is
for saddle stitching-center folding or for center folding in which
no saddle stitching is carried out. The judgment in step ST5 is
made based on information coming from main control device 201.
[0107] In the case of the saddle stitching-center folding (Y of
step ST5), motor M1 operates to move leading edge stopper 105 in
step ST6. A movement of the leading edge stopper 105 is a movement
to the second stop position where a center line of sheet S in its
conveyance direction agrees with a stapling position of stapler
103.
[0108] In step ST7, stitching process for stapling on sheets S is
carried out, and in step ST8, edges of sheets S are gripped again
by gripping member 106.
[0109] Gripping of sheet S is continued while leading edge stopper
105 is moving, and the gripping is released when the movement of
the leading edge stopper 105 is completed and when the sheet S is
set to the set height.
[0110] In step ST9 following the step ST8, leading edge stopper 105
moves and stops. This movement in ST9 is to move leading edge
stopper 105 to the third stop position where the center line of
sheet S agrees with a middle position between folding roller 53 and
folding roller 54.
[0111] In step ST10, the sheets are folded. The folded sheets S are
discharged to lower sheet discharge tray 83.
[0112] In a folding process without stitching, namely, in a center
folding process, the procedure proceeds from step ST5 to step ST11,
then, leading edge stopper 105 is moved to the third stop position,
and a center line of sheet S in the conveyance direction is caused
to agree with a middle position between folding roller 54 and
folding roller 55.
[0113] In step ST12 that follows step ST11, a folding process is
carried out, and the sheet S folded in step ST12 is discharged to
end the processes.
[0114] FIG. 6 is a diagram showing a sheet collecting device
relating to Embodiment 2 of the invention, and FIG. 7 is a flow
chart of operations of Embodiment 2.
[0115] Embodiment 2 is an example wherein side stitching is carried
out for sheets S stacked on an intermediate stack tray.
[0116] Side stitching is a processing to stitch edges of sheets S.
In the side stitching, stitched sheets S are discharged without
being folded.
[0117] Leading edge stopper 105 supports sheet S under the
illustrated state, in collecting and in stitching process of sheet
S.
[0118] When the stitching process has been completed, leading edge
stopper 105 is driven by solenoid SLa to rotate in the direction of
arrow W2, and releases sheet holding.
[0119] Sheet S released in terms of holding falls along
intermediate stack tray 100 to be discharged.
[0120] In FIG. 7, steps from step ST1 to step ST4 are the same as
those in FIG. 5, and sheet S is gripped by gripping member 106 at
the first stop position.
[0121] In step ST20 following ST4, leading edge stopper 105 moves
so that a stitching position of sheet S may agree with stitching
position of stapler 103.
[0122] In step ST 21, stapler 103 conducts a stitching process, and
in step ST22, gripping member 106 releases gripping and leading
edge stopper 105 rotates in the direction of arrow W2 to cause
sheet S to fall, thus, sheet S is discharged.
[0123] In the present embodiment, a sheet is caused to fall in the
direction of ejecting from a sheet ejecting device on a sheet
collecting board, and a position of a leading edge stopper is set
so that a trailing edge of the sheet (upper end) may be at a
constant position, whereby, downsizing is possible and a sheet
collecting device that operates stably can be realized.
* * * * *