JP3719013B2 - Sheet post-processing apparatus and image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In the present invention, sheets discharged after image formation from an image forming apparatus such as an electrophotographic copying machine, a printer, and a facsimile are sequentially taken into a sheet post-processing apparatus, and post-processing such as binding (stapling) and folding is performed on the sheet. The present invention relates to a sheet post-processing apparatus having a function of performing and discharging to a paper discharge unit.
[0002]
[Prior art]
A sheet post-processing device called a finisher is used as a device that collates a plurality of image-recorded recording sheets discharged from the image forming apparatus for each number of copies and binds them with staples.
[0003]
This finisher is connected to a main body of an image forming apparatus such as a copying machine or a printer, and is driven in response to a sequence operation of a copy or print process.
[0004]
Therefore, for an image forming apparatus capable of processing an image forming process at high speed, a finisher capable of high speed processing capable of performing a function following the processing speed is required.
[0005]
With regard to such a finisher, JP-A-60-142359, JP-A-60-158463, JP-A-62-239169, JP-A-62-228802, JP-A-63-267667, JP-A-2-276661, It is disclosed in Japanese Laid-Open Patent Publication Nos. 8-319054 and 5-41991.
[0006]
A bookbinding apparatus disclosed in Japanese Patent Application Laid-Open No. 60-183459 includes a cover sheet supply device, and performs bookbinding finishing operations such as punching or stapling after the copy paper group and the cover sheet are overlapped.
[0007]
JP-A-6-72064, JP-A-7-187479, and JP-A-8-192951 are sheet post-processing apparatuses having a saddle stitching processing function.
[0008]
A paper processing apparatus disclosed in Japanese Patent Laid-Open No. 10-148983 is a paper processing apparatus having a paper folding means for folding a paper sheet in half.
[0009]
[Problems to be solved by the invention]
(1) A conventional sheet post-processing apparatus is provided with a drive source (motor or the like) for a movable stopper member for a saddle stitching mode and a drive source (motor or the like) for a movable stopper member for saddle stitching. Therefore, the manufacturing cost is increased.
[0010]
(2) When a stepping motor is used as a drive source, a phase shift may occur due to an external force. Therefore, an initialization operation for positioning the drive startable position must be performed prior to the start of drive. When other parts are operated in conjunction with the operation of a certain part, it is necessary to limit the order of each initialization operation. If the order is incorrect, interference occurs between the operating members, resulting in failure of the apparatus. In order to prevent this, there is a drawback that the drive system of the apparatus becomes complicated.
[0011]
(3) The length of the sheet in the conveyance direction varies depending on environmental humidity, cutting accuracy, single-sided or double-sided recording, and the like. When the leading edge alignment is performed with reference to the leading edge of the sheet having the difference in length, and then saddle stitching and folding are performed, the trailing edge becomes uneven due to the difference in sheet length. When cutting the rear end irregular part of the sheet bundle that has been folded in half with a cutter or the like, if the sheet is cut by looking at the end of the outermost sheet, the sheet with a short overall length is inside the sheet bundle. However, the irregularity remains and the finished appearance of the sheet bundle is impaired.
[0012]
(4) A stepping motor is used as the drive source when the movable stopper member for folding is moved in accordance with the sheet size and stopped at a predetermined position to position the leading end of the sheet bundle being conveyed. In this case, the movable stopper member moves due to an impact force with the leading end portion of the sheet bundle conveyed. If the movable stopper member moves and deviates from the predetermined position, the bi-fold position at the center of the sheet is deviated, the leading end and the trailing end of the sheet bundle do not match, and the finished appearance of the sheet bundle is impaired.
[0013]
[Means for Solving the Problems]
The present invention has been made to solve the above-described problems in the saddle stitching and bi-folding process, and provides a sheet post-processing apparatus having the following means.
[0014]
(1) Conveying means for sequentially receiving and conveying the image-formed sheets carried out from the image forming apparatus, stacking means for positioning and stacking the received sheets, and staples for binding the sheets stacked on the stack means In the sheet post-processing apparatus having the means, both the end binding process for binding one end of the sheet and the saddle stitching process for binding the central part in the conveyance direction of the sheet can be performed, and the sheet can pass therethrough. And a stapling unit movable stopper member that moves to a predetermined position in the sheet conveying direction in accordance with the sheet size of the sheet placed on the stack unit and positions the sheet end portion. In conjunction with the movement of the movable binding member for saddle stitching processing, the sheet conveying path is blocked and the sheet edge is positioned. And a movable stopper member for end-stitching processing that enables the end-stitching processing and allows a sheet to be saddle-stitched while being retracted from the sheet conveyance path, and a sheet post-processing Apparatus (claim 1).
[0015]
(2) Conveying means for sequentially receiving and conveying image-formed sheets carried out from the image forming apparatus, stacking means for positioning and stacking the received sheets, and staples for binding sheets stacked on the stacking means In the sheet post-processing apparatus having the means, both the end binding process for binding one end of the sheet and the saddle stitching process for binding the central part in the conveyance direction of the sheet can be performed, and the sheet can pass therethrough. And a stapling unit movable stopper member that moves to a predetermined position in the sheet conveying direction in accordance with the sheet size of the sheet placed on the stack unit and positions the sheet end portion. In conjunction with the movement of the movable binding member for saddle stitching processing, the sheet conveying path is blocked and the sheet edge is positioned. An end-stitching process movable stopper member that enables the end-stitching process and allows a sheet to be saddle-stitched by being retracted from the sheet conveyance path. When the member is located at the home position, the movable binding member for the end binding process is set to the sheet leading end positioning position that blocks the sheet conveyance path, and when the power is turned on to the sheet post-processing apparatus A sheet post-processing apparatus that initializes a stop position of the stapling means after an initialization operation of the saddle stitching stopper unit.
(Claim 3).
[0016]
(3) Conveying means for sequentially receiving and conveying the image-formed sheets carried out from the image forming apparatus, stacking means for positioning and stacking the received sheets, and staples for binding the sheets stacked on the stacking means In the sheet post-processing apparatus having the means, both the end binding process for binding one end of the sheet and the saddle stitching process for binding the central part in the conveyance direction of the sheet can be performed, and the sheet can pass therethrough. And a stapling unit movable stopper member that moves to a predetermined position in the sheet conveying direction in accordance with the sheet size of the sheet placed on the stack unit and positions the sheet end portion. In conjunction with the movement of the movable binding member for saddle stitching processing, the sheet conveying path is blocked and the sheet edge is positioned. The edge-binding processing movable stopper member that allows the sheet to be saddle-stitched while being retracted from the sheet conveyance path, and the sheet that is carried into the sheet post-processing device. A sheet post-processing apparatus, comprising: a sheet positioning unit that makes it possible to adjust the position of the movable stopper member for saddle stitching processing according to the length in the conveying direction.
[0017]
(4) Conveying means for sequentially receiving and conveying image-formed sheets carried out from the image forming apparatus, stacking means for positioning and stacking the received sheets, and staples for binding the sheets stacked on the stack means And a folding means for folding the sheet in half, an end binding process for binding one end of the sheet, and a saddle stitching process for binding a central portion in the conveyance direction of the sheet The stapler is configured to be divided so that the sheet can pass through, and the sheet is moved to a predetermined position in the sheet conveyance direction corresponding to the sheet size of the sheet placed on the stacker. A movable stopper member for saddle stitching processing for positioning the sheet end portion and a movement of the movable stopper member for saddle stitching processing are linked to the movement. Then, the sheet feeding path is blocked and the sheet edge is positioned to enable the end binding process, and the end binding process movable stopper that allows the sheet to be saddle stitched while being retracted from the sheet feeding path is allowed to pass. A movable stopper member for folding means for positioning a sheet leading end by moving a member conveyed on a stacking base of the folding means to a predetermined position in the sheet conveying direction corresponding to the sheet size, and the sheet post-processing Measuring means for measuring the length of the sheet carried in the apparatus in the conveying direction, and a sheet positioning means for the saddle stitching movable stopper member and a sheet positioning means for the movable stopper member for the folding means, During the sheet post-processing operation to create one booklet, based on the measured value of the sheet length in the sheet conveying direction by the measuring means, the minimum in the sheet conveying direction Sheet post-processing apparatus, characterized in that the stop position in the criterion is determined is (claim 5).
[0018]
(5) Conveying means for sequentially receiving and conveying image-formed sheets carried out from the image forming apparatus, stacking means for positioning and stacking the received sheets, and staples for binding the sheets stacked on the stack means In the sheet post-processing apparatus, the sheet post-processing apparatus includes: a folding unit configured to position and place the stapled sheet on the sheet placing table and to fold the sheet in half. A movable stopper member for folding means for moving the sheet to a predetermined position in the sheet conveying direction corresponding to the sheet size to position the leading end of the sheet, a stepping motor driving means for movably driving the movable stopper member, Control means for controlling stepping motor drive means, and movable stopper member for the folding means Detecting means for detecting the entrance of the sheet, and controlling the stepping motor driving means by a detection signal of the detecting means, so that the stepping motor driving means immediately before the leading end of the sheet comes into contact with the movable stopper member The sheet post-processing apparatus is characterized in that the rotation of the sheet is stopped and fixed (claim 6).
[0019]
(6) An image forming apparatus comprising the sheet post-processing apparatus according to any one of claims 1 to 7 (claim 8).
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the sheet post-processing apparatus of the present invention will be described with reference to the accompanying drawings.
[0021]
FIG. 1 is an overall configuration diagram of an image forming apparatus A including a sheet post-processing device (finisher) FS and an automatic document feeder DF.
[0022]
The illustrated image forming apparatus A includes an image reading unit 1, an image processing unit 2, an image writing unit 3, an image forming unit 4, a cassette paper feeding unit 5, a large capacity paper feeding unit (LCT) 6, a fixing device 7, and a paper discharge. A unit 8 and an automatic duplex copy feeding unit (ADU) 9 are provided.
An automatic document feeder DF is mounted on the upper part of the image forming apparatus A. A sheet post-processing device (finisher) FS is connected to the left side of the image forming apparatus A shown in the drawing on the paper discharge unit 8 side.
[0023]
The document d placed on the document table of the automatic document feeder DF is conveyed in the direction of the arrow, and an image on one or both sides of the document is read by the optical system of the image reading unit (scanning exposure device) 1, and a CCD image sensor. 1A is read.
[0024]
The analog signal photoelectrically converted by the CCD image sensor 1 </ b> A is subjected to analog processing, A / D conversion, shading correction, image compression processing, and the like in the image processing unit 2, and then sent to the image writing unit 3.
[0025]
In the image writing unit 3, output light from the semiconductor laser is applied to the photosensitive drum of the image forming unit 4 to form a latent image. In the image forming unit 4, processing such as charging, exposure, development, transfer, separation, and cleaning is performed, and the image is transferred to the recording paper S conveyed from the cassette paper feeding unit 5 or the large-capacity paper feeding unit 6. . The recording paper S carrying the image is fixed by the fixing device 7 and sent from the paper discharge unit 8 to the sheet post-processing device FS. Alternatively, the recording sheet S that has undergone single-sided image processing sent to the automatic double-sided copy paper feeding unit 9 by the conveyance path switching plate 8A is again processed by the image forming unit 4 from the paper discharge unit 8 to the sheet post-processing device FS. It is sent.
[0026]
The sheet post-processing apparatus FS includes a fixed discharge tray 10, a cover (cover sheet) sheet feeding unit 40, a shift processing conveyance unit (large-capacity sheet conveyance unit) 20, an intermediate placement unit 30, and a staple from the upper stage in the figure. The means 50 and the folding means 60 are arranged in a column in a substantially vertical direction.
[0027]
An entrance conveyance unit 70 is disposed on the upper right side of the sheet post-processing apparatus FS. Further, on the left side of the sheet post-processing device FS in the figure, there are a movable paper discharge tray 81 for stacking sheets that have undergone end binding and shift processing, and a fixed paper discharge tray 82 for stacking sheets that have undergone saddle stitching and folding processing. Has been placed.
[0028]
FIG. 2 is a schematic diagram illustrating a sheet conveyance path of the sheet post-processing apparatus FS, and FIG. 3 is a cross-sectional view illustrating an upper mechanism of the sheet post-processing apparatus FS.
[0029]
The sheet post-processing device FS is installed with its position and height adjusted so that the receiving portion 71 of the recording paper S carried out from the image forming device A matches the paper discharge portion 8 of the image forming device A.
[0030]
The conveyance path of the recording sheet S connected downstream of the sheet conveyance of the inlet roller pair 72 of the receiving section 71 is the upper first conveyance path (1), the middle second conveyance path (2), and the lower third conveyance path. Branching into three systems {circle around (3)}, the recording paper S is fed to one of the transport paths by selecting the angle occupied by the switching gates G1 and G2.
[0031]
(1) First transport path {circle around (1)} (non-staple, non-sort mode, discharged to the fixed discharge tray 10 at the top of the apparatus)
The image-formed recording sheet S discharged from the image forming apparatus A is introduced into the receiving portion 71, conveyed by the inlet roller pair 72, and passes through the right passage 73 of the upper first switching gate G1. Then, it is nipped and conveyed by the upper conveying roller pair 74 (drive roller 74A, driven roller 74B) and conveying roller pair 75, and is further nipped by the discharge roller pair 76 to be fixedly discharged at the upper part outside the apparatus. It is discharged onto the tray 10 and stacked sequentially.
[0032]
In this sheet conveyance process, the switching gate G1 is swung by the drive of the solenoid SD1 to close the passage 77 and open the passage 73 to allow the recording paper S to pass through the fixed paper discharge tray 10.
[0033]
The fixed paper discharge tray 10 can accommodate a maximum of about 200 recording sheets S and can be easily taken out from the upper part of the sheet post-processing apparatus FS.
[0034]
(2) Second transport path {circle around (2)} (offset mode or non-sort mode, discharged to the movable discharge tray 81)
When this transport mode is set, the switching gate G1 closes the passage 73, keeps the passage 77 open, and allows the recording paper S to pass through the passage 77 when the solenoid SD1 is off.
[0035]
The image-formed recording sheet S discharged from the image forming apparatus A passes through the receiving portion 71 and the entrance roller pair 72, passes through the passage 77 formed in an open state below the switching gate G1, and is conveyed. Passed by the pair of rollers 78, passes through the passage 21 above the second switching gate G2 that is obliquely below the second transport path (2), is sandwiched by the pair of transport rollers 22, and passes through the passage 23 to be transported. The sheet is sandwiched between a roller pair (shift roller pair) 24, passes through a passage 25, and is discharged and placed on a movable discharge tray 81 outside the apparatus by a discharge roller pair 26 (upper roller 26 </ b> A and lower roller 26 </ b> B). Reference numeral 27 denotes a swinging means for swinging the upper roller 26A so as to be able to press and separate from the lower roller 26B.
[0036]
The movable sheet discharge tray 81 can accommodate up to about 3000 sheets (A4, B5) of recording sheets S.
[0037]
(3) Third conveyance path {circle around (3)} (edge binding mode, paper discharged to the movable paper discharge tray 81)
The image-formed recording sheet S that has been subjected to image formation processing in the image forming apparatus A and sent to the receiving section 71 of the sheet post-processing apparatus FS is a path below the inlet roller pair 72 and the first switching gate G1. Passing through 77, sandwiched between the pair of transport rollers 78 and transported to the third transport path (3).
[0038]
When the large recording paper S larger than A4 and B5 size is transported in the third transport path (3), the solenoid SD2 is driven, and the recording paper S passes through the passage 31A below the switching gate G2. The paper is sandwiched and transported by the downstream transport roller pair 32. The recording paper S is further sandwiched and fed out by a pair of downstream conveying rollers 34 (drive roller 34A, driven roller 34B), and is discharged into an upper space of the intermediate stacker 35 that is inclined, and the intermediate stacker 35 or the intermediate stacker 35 is discharged. After touching the upper surface of the recording paper S stacked thereon and sliding up, after the trailing edge of the recording paper S is discharged from the conveying roller pair 34, the recording paper S turns down due to its own weight, and the intermediate stacker 35 The end of the recording paper S abuts against the sheet abutting surface of an end closing movable stopper member (hereinafter referred to as an end closing stopper) 51 in the vicinity of the stapling means (binding means) 50. Stop.
[0039]
In the third transport path (3), in order to improve the copy productivity by transporting a small-sized recording paper S such as A4, B5 size, etc. continuously and efficiently, the passage 31A below the switching gate G2 is provided. Parallel passage 31B and switching gate G3 were provided.
[0040]
When the solenoid SD2 for the switching gate G2 and the solenoid SD3 for the switching gate G3 are driven together, the leading ends of the switching gates G2 and G3 both swing counterclockwise as shown in the figure, and the passages 21 and 31A are closed. Open the passage 31B. . The leading end portion of the first recording sheet S sent out from the conveyance roller pair 78 passes through the passage 31B and comes into contact with the circumferential surface of the conveyance roller pair 34 in the rotation stopped state to stop.
[0041]
Next, the energization of the solenoid SD3 is turned off, the tip of the switching gate G3 is swung clockwise, the passage 31B is closed, and the passage 31A is opened. The leading edge of the second recording sheet S sent out from the conveying roller pair 78 passes through the passage 31A and comes into contact with the peripheral surface of the conveying roller pair 34 in the rotation stopped state to stop.
[0042]
At a predetermined timing, the conveying roller pair 34 is driven and rotated, and the two recording sheets S are sandwiched and simultaneously conveyed, and discharged onto the intermediate stacker 35.
[0043]
Reference numeral 36 denotes a pair of width alignment members that are movably provided on both side surfaces of the intermediate stacker 35. The width aligning member 36 is movable in a direction orthogonal to the sheet conveying direction. When the recording sheet S is received on the intermediate stacker 35, the width aligning member 36 is opened wider than the sheet width and slides down on the intermediate stacker 35. When contacting the edge binding stopper 51 and stopping, the side edges in the width direction of the recording paper S are tapped to perform width alignment (width alignment) of the sheet bundle. At this stop position, when a predetermined number of recording sheets S are stacked and aligned on the intermediate stacker 35, the stapling unit 50 performs a binding process to bind the sheet bundle.
[0044]
A cutout portion is formed in a part of the sheet stacking surface of the intermediate stacker 35, and a plurality of discharge belts 38 wound around a driving pulley 37A and a driven pulley 37B are driven to be rotatable. A discharge claw 38 a is integrally formed on a part of the discharge belt 38, and the tip of the discharge belt 38 draws an elliptical locus as shown by a one-dot chain line in the drawing. The stapled sheet bundle is held on the trailing edge of the recording sheet S by the discharge claw 38a of the discharge belt 38, and is placed on the discharge belt 38. The sheet bundle slides obliquely upward on the loading surface of the intermediate stacker 35. It is pushed up and proceeds to the nip position of the discharge roller pair 26. The sheet bundle sandwiched between the rotating discharge roller pair 26 is discharged and stacked on the movable discharge tray 81.
[0045]
(4) Fourth transport path (4) (cover paper feed mode)
The cover sheet feeding means 40 is composed of a cover sheet placing portion comprising a sheet feeding tray 41, a movable bottom plate 42 and a push-up lever 43, and a cover sheet feeding means comprising a pickup roller 44, a feed roller 45, a separating roller 46, and the like. Yes.
[0046]
One cover sheet (cover sheet) K fed from the cover sheet feeding means 40 passes through the passage 47, passes through the nip position between the driving roller 74 </ b> A and the driven roller 74 </ b> C of the conveyance roller pair 74, and passes through the passage 79. Then, after passing through the transport roller pair 78, it reaches the intermediate stacker 35 through the transport roller pair 32, the passage 33, and the transport roller pair 34 in the third path (3).
[0047]
The conveying roller pair 74 includes a central driving roller 74A and two driven rollers 74B and 74C that are in pressure contact with the driving roller 74A. When the driving roller 74A is driven to rotate counterclockwise, the driven roller 74B rotates to the right and conveys the recording sheet S conveyed from the passage 73 upward. At the same time, the driven roller 74 </ b> C also rotates to the right to convey the cover sheet K conveyed from the passage 47 to the lower passage 79. Accordingly, it is possible to simultaneously convey the recording sheet S in the first conveyance path {circle around (1)} and the cover sheet K in the fourth conveyance path {circle around (4)} by the driving rotation of the drive roller 74A.
[0048]
(5) Fifth transport path <5> (saddle stitching mode)
FIG. 4 is a cross-sectional view showing the staple processing unit and the two-fold processing unit of the sheet post-processing apparatus FS.
[0049]
A stapling means 50, an end binding stopper 51, and a saddle stitching movable stopper member (hereinafter referred to as a saddle stitching stopper) 53 are formed in the binding unit U and can be pulled out to the front side of the sheet post-processing apparatus FS. Yes.
[0050]
The stapling means 50 is configured in a two-part structure of an upper mechanism and a lower mechanism, and a passage 52 through which the sheet S can pass is formed in the middle.
[0051]
When the saddle stitching mode is set, the end stitching stopper 51 in the vicinity of the staple processing position of the stapling means 50 is retracted from the transport path, and at the same time, the saddle stitching stopper 53 downstream thereof is activated to block the passage 52.
[0052]
The saddle stitching stopper 53 moves to a predetermined position and stops when the size of the cover sheet K and the recording sheet S (length in the transport direction) is set or detected.
[0053]
After the cover sheet K is placed at a predetermined position on the intermediate stacker 35, the recording sheet S carried out from the image forming apparatus A passes through the third conveyance path (3) from the inlet conveyance section 70 of the sheet post-processing apparatus FS. Then, the sheets are sequentially stacked on the upper surface of the cover sheet K placed on the intermediate stacker 35, and the leading end portion of the recording sheet S is brought into contact with the saddle stitching stopper 53 and positioned.
[0054]
After the final recording paper S is positioned and placed on the intermediate stacker 35, the saddle stitching process by the stapling means 50 is performed on the sheet bundle composed of the cover sheet K and all the pages of the recording paper S. By this saddle stitching process, the staple is driven into the center of the cover sheet K and the recording sheet S in the transport direction.
[0055]
(6) Sixth transport path {circle around (6)} (bi-fold processing mode)
After the saddle stitching process, the saddle stitch stopper 53 swings to open the passage downstream of the passage 52. The sheet bundle composed of the cover sheet K and the recording sheet S subjected to the saddle stitching process is conveyed by being guided by the guide plate 63 on the conveyance belt 62 obliquely below through the curved path 61 and further on the guide plate 64. The end of the sheet bundle comes into contact with a folding portion movable stopper member (hereinafter referred to as a folding portion stopper) 65 and stops at a predetermined position. The folding portion stopper 65 can be moved to a predetermined position by setting the sheet size or the detection result and the driving means.
[0056]
A protruding unit 66 is installed at the center in the conveyance direction of the stopped sheet bundle, that is, obliquely below the saddle stitching position. A folding roller pair 67 and a two-fold sheet conveying means 68 are installed obliquely above the saddle stitching position.
[0057]
FIG. 5 is a cross-sectional view of the folding means 60 including the ejection unit 66, the folding roller pair 67, the folded sheet conveying means 68, and the like.
[0058]
The movable holding member 662 moves straight along the guide bar 663 fixedly arranged in response to the folding start signal, and the protruding plate 661 fixed to the movable holding member 662 protrudes upward from the sheet placement surface. The protruding plate 661 has a thin knife shape, and its tip portion forms an acute angle.
[0059]
The leading end portion of the protruding plate 661 that protrudes straightly upward as shown in the figure pushes up the center portion of the sheet bundle composed of the cover sheet K and the recording sheet S, and pushes the nip portion of the folding roller pair 67 through the sheet bundle. Swing and separate.
[0060]
After the leading end of the protruding plate 661 passes through the nip portion, the protruding plate 661 moves backward, and the central portion of the sheet bundle is pinched by the folding roller pair 67 to form a fold. This fold line substantially coincides with the staple needle driving position on the sheet bundle by the saddle stitching process.
[0061]
One pressing means 67A of the pair of folding rollers 67 supports a first pressing roller 671A that is driven by being connected to a driving source, and the first pressing roller 671A so as to be rotatable, with the support shaft 673A as a center. Connected to the drive source and driven by a foldable arm 672A and a front folding portion that is locked to one end of the arm 672A and biases the first pressing roller 671A toward the nip position, and a drive source The second pressing roller 676A, and the first folding roller 671A, a pulley 675A coaxial with the second pressing roller 676A, and a folding portion at the rear stage composed of a conveyor belt 677A wound around the second pressing roller 676A. Has been.
[0062]
The other pressing means 67B has the same configuration and includes a first pressing roller 671B, an arm 672B, a support shaft 673B, a spring 674B, a pulley 675B, a second pressing roller 676B, and a conveying belt 677B. The second pressing rollers 676A and 676B are supported to be swingable by an arm, a support shaft, and a spring (not shown) similar to the first pressing rollers 671A and 671B.
[0063]
The central portion of the sheet bundle formed with a fold by being pressed by the rotating first pressing rollers 671A and 671B is sandwiched and conveyed by the conveying belts 677A and 677B, and the nip position between the second pressing rollers 676A and 676B. In this position, the crease is further tightened and fed into the folded sheet conveying means 68.
[0064]
The double-folded sheet conveying unit 68 includes a lower conveying belt 681 and an upper conveying belt 682 that convey the sheet bundle while sandwiching the sheet bundle. The lower conveyor belt 681 is stretched between the driving roller 683 and the driven roller 685 and is rotatable. The upper conveying belt 682 is stretched between the driving roller 684 and the driven roller 686 and is rotatable.
[0065]
The sheet bundle fed into the folded sheet conveying means 68 is nipped between the lower conveying belt 681 and the upper conveying belt 682 and conveyed, and is discharged onto a fixed paper discharge tray 82 outside the apparatus.
[0066]
FIG. 6 is a schematic diagram illustrating the conveyance path of the cover sheet K and the recording sheet S, the saddle stitching and folding process of the sheet bundle, and FIG. 7A is a perspective view of the booklet that has been subjected to the saddle stitching and folding process. FIG. 7B is a perspective view showing a state in which the post-processed booklet is double-opened.
[0067]
On the sheet feeding tray 41 of the cover sheet feeding means 40, the cover sheet K is placed with the first side (first page p1 and eighth page p8) facing upward. The cover sheet K fed from the sheet feeding tray 41 by the sheet feeding means is transported through the fourth transport path (4) and the third transport path (3), and on the intermediate stacker 35, the first surface. (P1 and p8) are placed on the lower side.
[0068]
Next, the image-formed recording sheet S carried out from the image forming apparatus A is introduced into the sheet post-processing apparatus FS with the first side (the third page p3 and the sixth page p6) facing down. This recording sheet S is transported from the entrance transport section 70 to the third transport path (3), and on the cover sheet K placed on the intermediate stacker 35, the first surface (p3, p6) is on the lower side. Placed.
[0069]
The cover sheet K and the recording sheet S are aligned on the intermediate stacker 35, and the staple needle SP is driven by the stapling means 50 to perform saddle stitching.
[0070]
The sheet bundle subjected to the saddle stitching process passes through the fifth conveyance path (5), is placed at a predetermined position on the guide plate 64 and the conveyance belt 62, and stops. At this time, the sheet bundle is placed with the recording paper S on the first side (p3, p6) on the upper side and the cover sheet K on the recording paper S on the first side (p1, p8) on the upper side.
[0071]
Next, the folding operation is performed by the push-up operation of the ejection unit 66 and the driving rotation of the folding roller pair 67, and then the folding unit 66 is sandwiched and conveyed by the folded sheet conveying means 68, and is fixed outside the machine. 82 is discharged.
[0072]
The booklet created by the saddle stitching process and the half-folding process has the first side (p1, p8) of the cover K facing outward, the second side (p2, p7) on the back side, and the contents inside the booklet. The first side (p3, p6) of the recording paper S and the second side (p4, p5) of the recording paper S are arranged on the inside thereof, and the page alignment of the booklet consisting of 8 pages (p1 to p8) as shown in the figure. it can.
[0073]
FIG. 8 is a block diagram showing the control of the sheet post-processing apparatus according to the present invention.
[0074]
In the control unit 556 of the image forming apparatus A, the booklet creation auto mode is selected and set, the cover K is loaded on the paper feed tray 41, and printing is started. The sheet S carrying the image is subjected to the saddle stitching process and the half-folding process by the sheet post-processing device FS, and a booklet is continuously generated and discharged.
[0075]
In the operation section of the sheet post-processing apparatus FS, the booklet creation manual mode is selected and set, and the cover sheet K and an image-formed recording sheet S are stacked on the sheet feeding tray 41 and sent out. When the operation is started, the control unit of the sheet post-processing device FS performs saddle stitching processing and bi-folding processing on the cover sheet K and the recording paper S by the sheet post-processing device FS, thereby creating one booklet. Discharged.
[0076]
9 is a cross-sectional view of the staple processing unit of the sheet post-processing apparatus, and FIG. 10 is a plan view of the staple processing unit in FIG.
[0077]
The staple processing unit includes a staple unit 50 that is divided into an upper mechanism 50A and a lower mechanism 50B, and a drive unit that drives an end binding stopper 51 and a saddle stitch stopper 53.
[0078]
Two sets of stapling means 50 are arranged in a direction orthogonal to the sheet conveying direction, and can be moved in a direction orthogonal to the sheet conveying direction by a driving means (not shown). With this stapling means 50, staples are placed at two central sorting positions in the sheet width direction or at one corner portion corresponding to the sheet size.
[0079]
The end binding stopper 51 is supported by the upper mechanism 50A of the stapling means 50 and moves integrally in a direction perpendicular to the sheet conveying direction.
[0080]
One end of the end binding stopper 51 is a sheet front end abutting surface 51A, and the other end is fitted to a support shaft 501 supported by the upper mechanism 50A of the stapling means 50 and is supported so as to be swingable. Yes.
[0081]
A torsion spring 502 is wound around the support shaft 501, and the sheet leading end abutting surface 51A side of the end binding stopper 51 is spring-biased toward the passage 52, and is stopped at the sheet stop position during the end binding process.
[0082]
A support plate 503 fixed to the frame of the binding unit U is disposed in the middle part of the two sets of stapling means 50. A release lever 54 is swingably supported on a support shaft 504 supported on one end of the support plate 503.
[0083]
A pressing shaft body 552 of a saddle stitching stopper unit 55 described later comes into contact with one lever portion 54A of the release lever 54 so as to be able to contact and separate. The other lever portion 54B of the release lever 54 presses the base portion of the sheet leading end abutting surface 51A of the end binding stopper 51 to lower it to a predetermined stop position.
[0084]
The torsion spring 505 wound around the support shaft 504 urges and swings the release lever 54 and stops it at the upper retracted stop position.
[0085]
Two guide bars 506 supported at both ends by the support plate 503 fixed above the passage 52 move the saddle stitch stopper unit 55 linearly.
[0086]
The frame body 551 of the saddle stitching stopper unit 55 includes a bearing portion that slides on the two guide bars 506 and a detection portion 556 that projects from one end of the frame body 551.
[0087]
A pressing shaft body 552 is fixed in the vicinity of one end portion of the frame body 551, and a support shaft 553 is fixed to the other end portion. The saddle stitching stopper 53 is fitted to the support shaft 553 and swings. A torsion spring 531 is wound around the support shaft 553 to urge the saddle stitch stopper 53 in a direction to retract upward from the passage 52.
[0088]
A lower end portion of the saddle stitching stopper 53 is a stopper surface portion 53A that contacts the leading end portion of the sheet and performs positioning of the sheet bundle during the saddle stitching process. The upper end portion of the saddle stitching stopper 53 is a cam follower surface portion that comes into contact with a cam surface of an eccentric cam 555 described later. The torsion spring 531 wound around the support shaft 553 presses and urges the saddle stitch stopper 53 against the cam surface of the eccentric cam 555.
[0089]
FIG. 11A is a plan view showing a drive system of the saddle stitching stopper unit 55, and FIG. 11B is a front view of the drive system of the saddle stitching stopper unit 55.
[0090]
The gear G1 fixed to the drive shaft of the motor M1 fixed to the frame body 551 meshes with the gear G2 fixed to one end of the cam shaft 554 that is rotatably supported by the frame body 551. An eccentric cam 555 and a home position detector 556 are integrally formed and fixed to the other end of the cam shaft 554.
[0091]
The home position detection unit 556 has a shape in which a notch is provided in a part of the hollow cylindrical surface, and corrects the home position of the saddle stitching stopper 53 by detecting the notch by the photosensor PS3.
[0092]
A timing belt 557 is locked to a side surface of the frame body 551 by a locking member (not shown). A timing pulley 558 around which the timing belt 557 is wound is rotated from a motor M2 as a drive source via a drive transmission system such as a gear train.
[0093]
FIG. 12 is a front view showing an interlocking mechanism between the end binding stopper 51 and the saddle stitch stopper 53.
[0094]
FIG. 12A is a front view showing the saddle stitching process. During the saddle stitching process, the saddle stitch stopper unit 55 is moved to a predetermined position in the sheet conveyance direction corresponding to the sheet size and stopped by a driving mechanism including the driving source (not shown), the timing pulley 558, the timing belt 557, and the like. .
[0095]
At this stop position, the saddle stitch stopper 53 is driven by the motor M1 and swings, and is held in the illustrated stop state, thereby enabling the leading edge of the sheet to be aligned. After the saddle stitching process, the saddle stitch stopper 53 is swung by the reverse drive of the motor M1 and retracts to the illustrated wavy line position.
[0096]
In the saddle stitching processing stop position, the end binding stopper 51 is urged by the torsion spring 502 and urged counterclockwise around the support shaft 501. By the release lever 54 biased by the torsion spring 505 having a biasing force stronger than the biasing force, the lever portion 54B presses the locking portion 51B, and the end binding stopper 51 swings and stops at a predetermined retracted position. . Note that the release lever 54 is urged by the torsion spring 505 and is swung clockwise around the support shaft 504 so as to come into pressure contact with the locking portion 51B of the end binding stopper 51.
[0097]
FIG. 12B shows the end binding process. During the end binding process, the saddle stitch stopper unit 55 moves along the guide bar 506 by the drive mechanism and stops. That is, when the home position detection unit 556 of the moving saddle stitch stopper unit 55 approaches the detection position of the photosensor PS2, the pressing shaft body 552 comes into contact with one lever portion 54A of the release lever 54.
[0098]
When the saddle stitching stopper unit 55 overcomes the torque of the torsion spring 505 and further advances and continues to push and swing the lever portion 54A, the other lever portion 54B also swings in the same manner, and the end binding stopper 51 Press down on the top edge. By this depressing operation, the end binding stopper 51 located at the upper retracted position is swung in the illustrated counterclockwise direction around the support shaft 501, and the sheet front end abutting surface 51 </ b> A is a sheet alignment for a predetermined end binding process. Stop in position.
[0099]
Since the torque of the torsion spring 505 of the release lever 54 is set to be larger than the torque of the torsion spring 502 of the end binding stopper 51, the torsion spring 505 of the release lever 54 overcomes the biasing force of the torsion spring 502 and ends. The binding stopper 51 is lifted to the upper retracted position.
[0100]
As described above, by selecting the sheet stop for the saddle stitching process and the sheet stop for the end stitching process according to the moving direction of the saddle stitching stopper unit 55, the driving mechanism becomes simple and reliable.
[0101]
FIG. 12C is a plan view showing an end binding process in which staple needles SP are hit at two central sorting positions in the vicinity of the end surface of the sheet S. FIG.
[0102]
FIG. 12D is a plan view showing an end binding process in which the staple needle SP is driven at one place in the vicinity of the corner portion of the sheet S.
[0103]
FIG. 12E is a plan view showing a saddle stitching process in which staple needles SP are hit at two centrally distributed locations along the crease of the sheet S. FIG.
[0104]
Next, initialization of the drive source in the interlocking mechanism of the saddle stitching stopper 53 and the end stitching stopper 51 will be described.
[0105]
FIG. 10 is a plan view showing a state in which the two sets of stapling means 50A arranged in parallel in the direction orthogonal to the sheet conveying direction perform the saddle stitching process at two centrally distributed portions of the sheet.
[0106]
When the power is supplied to the sheet post-processing apparatus FS, first, the motor M1 shown in FIG. 11 starts to drive, rotates the home position detection unit 556, and detects it by the photosensor PS3, thereby detecting the saddle stitching stopper 53. Correct the home position and stop.
[0107]
Next, the saddle stitching stopper unit 55 shown in FIG. 11 is driven by the motor M2 to move toward the end stitching stopper 51 (in the direction of the one-dot chain line in FIG. 12A), and the pressing shaft 552 is the lever of the release lever 54. The portion 54A is pressed, the lever portion 54B is lowered, the home position detection unit 556 at the tip of the frame 551 is moved to the detection position of the photosensor PS2, the home position of the saddle stitching stopper unit 55 is detected, and the saddle stitching stopper The unit 55 is initialized.
[0108]
After initialization by the movement of the saddle stitching stopper unit 55, the stapling means 50 to which the end stitching stopper 51 is attached is initialized.
[0109]
9 and 10, a detection unit 50a protrudes from the tip of the bottom plate 500 of the lower mechanism 50B of the stapling means 50. The position of the detection unit 50a is detected by a photosensor PS4 fixed to the binding unit U, and the home position of the stapling means 50 is detected.
[0110]
After the sheet post-processing apparatus FS is turned on and the saddle stitching stopper unit 55 is initialized, the stapling means 50 located outside the home position passes through the motor M4, the drive transmission system, the timing belt 509, etc., and the sheet conveying direction. It moves in the direction orthogonal to and stops at the home position.
[0111]
In this home position, the end binding stopper 51 is moved by being pressed by the release lever 54 after initialization, stops at a predetermined position, blocks the passage 52, and enables end binding processing.
[0112]
If the initialization order is the reverse of the above, the staple means 50 is first moved to the home position, and then the saddle stitching stopper unit 55 is moved to the home position. If the binding stopper unit 55 is moved from the home position, the engagement between the lever portion 54B of the release lever 54 and the engaging portion 51B of the end binding stopper 51 attached to the stapling means 50 may be disengaged, causing interference.
[0113]
FIGS. 13A to 13D are schematic views showing the processes of the saddle stitching process and the folding process.
[0114]
13A is a plan view of a plurality of sheets S1 and S2 that are placed on the intermediate stacker 35, aligned at the edge by the saddle stitching stopper 53, and subjected to the saddle stitching process, and FIG. 13B is subjected to the saddle stitching process. FIG. 13C is a front view of the sheets S1 and S2 subjected to the middle folding process. FIG. 14 is a block diagram showing the control of the sheet post-processing apparatus FS.
[0115]
A plurality of sheets sent from the image forming apparatus A to the sheet post-processing apparatus FS are passed through the leading end and the trailing end of the sheet by the sheet passing sensor PS1 installed in the vicinity of the receiving portion 71 of the entrance conveying portion 70 shown in FIG. Is detected.
[0116]
In the control means 90, the length (sheet size) in the sheet conveyance direction for each passing sheet is measured by a sheet leading edge / rear edge detection signal from the sheet passing sensor PS1 and a timer. The control means 90 sets the minimum size L after measuring all the sheet sizes of each sheet for one booklet.
[0117]
Next, based on the set value of the minimum size L, the control unit 90 aligns the leading edges so that the staple processing position (staple needle SP driving position) is one half (L / 2) of the minimum size L. As is done, the saddle stitching stopper 53 is moved and positioned.
[0118]
Further, the control means 90 is installed by moving the folding portion stopper 65 of the folding means 60 shown in FIGS. 4 and 5 to a position where the length of the sheet leading edge and the crease is equal to the above L / 2. .
[0119]
After the half-folding process, the end of the booklet is aligned with the front end of the minimum size sheet, and a sheet longer than the minimum size protrudes as an ear part a. This ear | edge part a is cut | judged on the basis of the short front end side with which the sheet | seat of the minimum size was aligned after folding in half. A booklet composed of sheets after cutting is easily and uniformly aligned with the minimum trimming size regardless of the size of the sheet (see FIG. 13D).
[0120]
In consideration of misalignment of the sheet bundle and uneven end of the thick sheet bundle, the cutting dimension may be set to a dimension slightly shorter (1-2 mm) than L / 2.
[0121]
The holding member 651 that holds the folding portion stopper 65 of the folding means 60 shown in FIGS. 4 and 5 is guided by the guide bar 652 and can move linearly. The auxiliary member 651 is moved by a timing belt, a drive transmission system, and a motor M4 (not shown).
[0122]
The motor M4 is a stepping motor. When the size of the sheet fed into the sheet post-processing device FS (the length in the sheet conveyance direction) is detected, the motor M4 is driven, and the folding stopper 65 is moved to a predetermined position corresponding to the sheet size and stopped. To do. The folded sheet stopper 65 in the stopped state slides and collides with the guide plate 64 on which the saddle stitched sheet bundle is inclined.
[0123]
The folding portion stopper 65 moves the saddle stitched sheet bundle conveyed on the guide plate (stack base) 64 of the folding means 60 to a predetermined position in the sheet conveying direction according to the sheet size and positions the sheet leading end. This is a movable stopper member for the folding means, and is driven by a motor (stepping motor) M4, a stepping motor driving means, a control means 90, and the like.
[0124]
At the bottom of the inclined guide plate 64, detection means for detecting the entrance of the sheet bundle into the folding portion stopper 65 is disposed. The detection means includes an actuator 653 and a photosensor PS5. The actuator 653 is supported by the guide plate 64 so as to be capable of swinging, and swings in contact with the leading end of the sheet S sliding down the guide plate 64, thereby intermittently detecting the optical path of the photosensor PS5. The passage of the tip of S is detected.
[0125]
The stepping motor driving means of the control means 90 is controlled so as to prevent the rotation of the stepping motor M4 immediately before the leading edge of the sheet bundle abuts against the folding portion stopper 65, based on the leading edge passage detection signal of the sheet S by the photosensor PS5. To do.
[0126]
Even when the thick sheet bundle subjected to saddle stitching slides on the surface of the guide plate 64 at a high speed and collides with the folding stopper 65, the folding stopper 65 is electrically fixed by the stepping motor M4. Therefore, it does not move from a predetermined position withstanding the impact at the time of the collision. Therefore, the middle folding process is performed at an accurate position.
[0127]
In the embodiment of the present invention, a sheet post-processing apparatus connected to a copying machine is shown. However, the present invention is also applicable to an image forming apparatus such as a printer or a facsimile, or a sheet post-processing apparatus used by connecting to a light printing machine. Is possible.
[0128]
【The invention's effect】
According to Claims 1 and 2 of the sheet post-processing apparatus of the present invention, the end stitching stopper occupies the operating position and the retracted position in conjunction with the movement of the saddle stitching stopper. Both stoppers can be reliably driven by the means.
[0129]
According to the third aspect, the saddle stitching stopper unit moving in the sheet conveying direction and the end binding stopper mounted on the stapling means movable in the direction orthogonal to the sheet conveying direction interfere with each other during the end binding process. Malfunctions and failures are prevented.
[0130]
According to the fourth aspect, even when there is a variation in the specified length in the sheet conveyance direction, the saddle stitching position and the edge stitching position can be accurately fine-tuned and post-processed.
[0131]
According to claim 5, when there is a variation in the specified length in the conveyance direction of the sheet, the minimum length of the sheet is measured and selected, and the post-processing is performed by finely adjusting the position of the saddle stitching and the position of the edge binding. By easily cutting the end portion of the booklet that has been folded in half, the quality of the finished booklet can be improved.
[0132]
According to claims 6 and 7, when the leading end of the sheet bundle subjected to saddle stitching is abutted against a stopper for abutting the leading end of the sheet that can be moved by the folding means, the stopper is moved by an impact with the leading end of the sheet bundle. Accordingly, the folding position is prevented from being shifted, so that the folding process is performed at an accurate position.
[0133]
According to the eighth aspect, desired digital processing is performed by an image forming apparatus such as a copying machine, a printer, or a facsimile, and the discharged recording paper has processing modes such as edge binding, saddle stitching, and folding in the sheet post-processing apparatus. The pages are aligned and placed in the correct position.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an image forming apparatus including a sheet post-processing apparatus and an automatic document feeder.
FIG. 2 is a schematic diagram illustrating a sheet conveyance path of a sheet post-processing apparatus.
FIG. 3 is a cross-sectional view showing an upper mechanism of a sheet post-processing apparatus.
FIG. 4 is a cross-sectional view illustrating a staple processing unit and a two-fold processing unit of the sheet post-processing apparatus.
FIG. 5 is a cross-sectional view of a protrusion unit, a pair of folding rollers, and a folded sheet conveying unit.
FIG. 6 is a schematic diagram showing a cover and recording sheet conveyance path, a sheet bundle saddle stitching, and a folding process.
FIG. 7 is a perspective view of a booklet that has been subjected to post-processing of saddle stitching and bi-folding, and a perspective view showing a state in which the post-processed booklet is double-opened.
FIG. 8 is a block diagram showing control of the sheet post-processing apparatus.
FIG. 9 is a cross-sectional view of a staple processing unit of the sheet post-processing apparatus.
10 is a plan view of the staple processing unit in FIG.
FIG. 11 is a plan view and a front view showing a drive system of the saddle stitching stopper unit.
FIG. 12 is a front view of the saddle stitching processing unit and the edge stitching stopper during the saddle stitching process and the edge stitching process, and a plan view showing the staple processing position and the stopper position of the sheet.
FIG. 13 is a schematic diagram showing a process of saddle stitching processing and folding processing.
FIG. 14 is a block diagram illustrating control of the sheet post-processing apparatus.
[Explanation of symbols]
10 Fixed paper tray
20 Shift processing transport section (large capacity discharge transport path)
30 Intermediate mounting means (stacking means)
35 Intermediate stacker
40 Cover paper feeding means
50 Staple means
51 Movable stopper member for end binding (end binding stopper)
53 Moveable stopper member for saddle stitching (saddle stitching stopper)
54 Release lever
55 Saddle Stitch Stopper Unit
60 folding means
62 Conveyor belt
63 Guide plate
64 Guide plate (stack base)
65 Folding part movable stopper member (Folding part stopper)
653 Actuator
66 Projection unit
67 Folding roller pair
70 Inlet transport section (transport means)
71 Receiving part
72 Inlet roller pair
81 Movable output tray
82 Fixed paper tray
90 Control means
A Image forming apparatus
FS sheet post-processing equipment (finisher)
K cover (cover sheet)
M1, M2, M3, M4 motor (stepping motor)
PS1 Sheet passing sensor
PS2, PS3, PS4, PS5 Photo sensor
S Recording paper
S1, S2 sheet
SP staple needle

Claims (8)

Conveying means for sequentially receiving and conveying the image-formed sheets carried out from the image forming apparatus, stacking means for positioning and stacking the received sheets, and stapling means for binding the sheets stacked on the stacking means In a sheet post-processing apparatus having
A stapler configured to be configured so as to be capable of performing both of an end binding process for binding one end of the sheet and a saddle stitching process for binding a central portion in the conveyance direction of the sheet, and to allow the sheet to pass;
A saddle-stitching movable stopper member that moves to a predetermined position in the sheet conveyance direction in accordance with the sheet size of the sheet placed on the stack means and positions the sheet end portion;
In conjunction with the movement of the movable binding member for saddle stitching processing, the sheet conveying path is blocked and the sheet end portion is positioned to enable the end binding process, and the saddle stitching process is performed while avoiding the sheet conveying path. A sheet post-processing apparatus, comprising: an end-stitching movable stopper member that allows a sheet to pass therethrough. The sheet post-processing according to claim 1, wherein when the saddle stitching stopper unit having the saddle stitching process movable stopper member is in a home position, the end stitching process movable stopper member is in a sheet positioning stop position. apparatus. Conveying means for sequentially receiving and conveying the image-formed sheets carried out from the image forming apparatus, stacking means for positioning and stacking the received sheets, and stapling means for binding the sheets stacked on the stacking means In a sheet post-processing apparatus having
A stapler configured to be configured so as to be capable of performing both of an end binding process for binding one end of the sheet and a saddle stitching process for binding a central portion in the conveyance direction of the sheet, and to allow the sheet to pass;
A saddle-stitching movable stopper member that moves to a predetermined position in the sheet conveyance direction in accordance with the sheet size of the sheet placed on the stack means and positions the sheet end portion;
In conjunction with the movement of the movable binding member for saddle stitching processing, the sheet conveying path is blocked and the sheet end portion is positioned to enable the end binding process, and the saddle stitching process is performed while avoiding the sheet conveying path. A movable stopper member for end binding processing that allows the sheet to pass through,
When the saddle stitching process movable stopper member is positioned at the home position, the end stitching process movable stopper member is configured to be set at a sheet leading edge positioning position that blocks the sheet conveyance path,
The sheet post-processing apparatus, wherein when the power is supplied to the sheet post-processing apparatus, the stop position of the stapling unit is initialized after the initialization operation of the saddle stitching stopper unit. Conveying means for sequentially receiving and conveying the image-formed sheets carried out from the image forming apparatus, stacking means for positioning and stacking the received sheets, and stapling means for binding the sheets stacked on the stacking means In a sheet post-processing apparatus having
A stapler configured to be configured so as to be capable of performing both of an end binding process for binding one end of the sheet and a saddle stitching process for binding a central portion in the conveyance direction of the sheet, and to allow the sheet to pass;
A saddle-stitching movable stopper member that moves to a predetermined position in the sheet conveyance direction in accordance with the sheet size of the sheet placed on the stack means and positions the sheet end portion;
In conjunction with the movement of the movable binding member for saddle stitching processing, the sheet conveying path is blocked and the sheet end portion is positioned to enable the end binding process, and the saddle stitching process is performed while avoiding the sheet conveying path. A movable stopper member for end binding processing that allows the sheet to pass through;
A sheet positioning unit that enables adjustment of the position of the movable stopper member for the saddle stitching process according to the length of the sheet carried into the sheet post-processing apparatus in the conveyance direction. Post-processing device. Conveying means for sequentially receiving and conveying the image-formed sheets carried out from the image forming apparatus; stacking means for positioning and stacking the received sheets; and stapling means for binding the sheets stacked on the stack means; In a sheet post-processing apparatus having folding means for folding the sheet in half,
A stapler configured to be configured so as to be capable of performing both of an end binding process for binding one end of the sheet and a saddle stitching process for binding a central portion in the conveyance direction of the sheet, and to allow the sheet to pass;
A saddle-stitching movable stopper member that moves to a predetermined position in the sheet conveyance direction in accordance with the sheet size of the sheet placed on the stack means and positions the sheet end portion;
In conjunction with the movement of the movable binding member for saddle stitching processing, the sheet conveying path is blocked and the sheet end portion is positioned to enable the end binding process, and the saddle stitching process is performed while avoiding the sheet conveying path. A movable stopper member for end binding processing that allows the sheet to pass through;
A movable stopper member for folding means for positioning the leading end of the sheet by moving the sheet conveyed on the stacking table of the folding means to a predetermined position in the sheet conveying direction corresponding to the sheet size;
Measuring means for measuring the length in the conveyance direction of the sheet carried into the sheet post-processing apparatus,
The sheet positioning means of the movable stopper member for saddle stitching processing and the sheet positioning means of the movable stopper member for folding means are sheets in the sheet conveyance direction by the measuring means during the sheet post-processing operation for creating one booklet. A sheet post-processing apparatus, wherein a stop position is determined on the basis of a minimum length in a sheet conveyance direction based on a measurement value of a length. Conveying means for sequentially receiving and conveying the image-formed sheets carried out from the image forming apparatus; stacking means for positioning and stacking the received sheets; and stapling means for binding the sheets stacked on the stack means; A sheet post-processing apparatus having a folding means for positioning and placing the stapled sheet on a sheet placing table and folding the sheet in half;
A movable stopper member for folding means for positioning the leading end of the sheet by moving the sheet conveyed on the stacking table of the folding means to a predetermined position in the sheet conveying direction corresponding to the sheet size;
Stepping motor driving means for movably driving the movable stopper member;
Control means for controlling the stepping motor driving means;
Detecting means for detecting entry of the sheet into the movable stopper member for the folding means,
The stepping motor driving unit is controlled by a detection signal of the detecting unit, and the rotation of the stepping motor driving unit is stopped and fixed immediately before the leading end of the sheet comes into contact with the movable stopper member. Post-processing device. The sheet post-processing apparatus according to claim 6, wherein the control unit releases the rotation stop of the stepping motor after the bi-folding process is started. An image forming apparatus comprising the sheet post-processing apparatus according to claim 1.

Images