JP2003233228A - Paper post-processor and image forming system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper post-processor and an image forming system which can continue the paper-feeding of cover sheets efficiently without stopping image forming processing even when there is no cover sheet in a paper-feeding tray of one side in a post-processor where the same size cover sheets are stored in a plurality of the paper-feeding trays. <P>SOLUTION: This post-processor FS is provided with paper-feeding devices of multi-steps which consists of the paper-feeding tray storing cover sheets, a paper-feeding means feeding cover papers and a remaining paper detecting means. In the case that the same size cover papers are stored in the paper- feeding tray of multi-steps, when the remaining paper detecting means of one side paper-feeding device detects that there is no cover sheet in the paper-feeding tray, a controlling means acts the paper-feeding means of the other side paper- feeding device and follows the paper-feeding operation of one side paper-feeding device and starts the paper-feeding operation of the cover sheets by means of the other side paper-feeding device. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed tray for containing cover sheets, and a paper feed means for feeding the cover sheets.
The present invention relates to a sheet post-processing apparatus including a plurality of sheet feeding devices including the sheet feeding apparatus, and an image forming system including the sheet post-processing apparatus.

[0002]

2. Description of the Related Art In recent years, a sheet post-processing apparatus performs edge-stitching processing, saddle-stitching processing on a sheet on which an image is recorded by an image forming apparatus such as a copying machine, a printer, or a complex machine thereof.
There is provided an image forming system including a sheet post-processing device that performs center folding processing and makes a booklet like a weekly magazine, and an image forming apparatus.

As a sheet post-processing device for carrying out saddle stitching processing on a bundle of sheets made up of a plurality of sheets, there is conventionally known Japanese Patent Laid-Open No.
-72064, JP-A-7-187479, JP-A-8
No. 192951 publications and the like are known.

Further, as post-processing devices capable of performing center folding processing, Japanese Patent Laid-Open Nos. 7-48062 and 10-148 are known.
983, JP-A-10-167562, JP-A-11-
No. 348451 and US Pat. No. 5,108,0
No. 82 specification is proposed.

Further, Japanese Unexamined Patent Publication No. 2001-261220 describes a sheet post-processing device for superposing a cover sheet on a recording sheet discharged from an image forming apparatus and binding and folding the book to make a book. There is.

[0006]

SUMMARY OF THE INVENTION In a conventional sheet post-processing apparatus having a plurality of sheet feeding devices each including a sheet feeding tray for storing a cover sheet and a sheet feeding unit for feeding the cover sheet, Even if the cover sheets accommodated in the paper feed tray of No. 1 have the same size, if the remaining paper amount detection means of one of the paper feed devices detects the absence of the cover paper in the paper feed tray,
The image forming process was stopped.

As a result, there arises a problem that the image forming process is interrupted, unnecessary waiting time and paper replenishing operation are required, and other image forming processes cannot be performed and become stagnant.

The present invention provides a post-processing apparatus and an image forming system including the post-processing apparatus, which solves the above-mentioned problems in the conventional paper post-processing apparatus and achieves efficiency in feeding cover sheets. The purpose is to

[0009]

The objects of the present invention can be achieved by the following inventions.

(1) In a sheet post-processing apparatus in which recording sheets discharged from an image forming apparatus are sequentially sent to a stacking unit and post-processed by a post-processing unit, the sheet post-processing apparatus supplies a cover sheet. When a plurality of paper feed devices each including a paper tray, a paper feed unit for feeding cover paper, and a paper remaining amount detection unit are provided, and cover papers of the same size are accommodated in the plurality of paper feed trays, When the remaining paper amount detecting means of one of the paper feeding devices detects the absence of cover paper in the paper feeding tray, the control means for controlling the paper feeding device controls the paper feeding means of the other paper feeding device. A sheet post-processing apparatus that is operated to start a sheet feeding operation of a cover sheet by the other sheet feeding apparatus, following the sheet feeding operation of the one sheet feeding apparatus.

(2) In a sheet post-processing apparatus in which recording sheets discharged from the image forming apparatus are sequentially sent to a stacking unit and post-processed by a post-processing unit, the sheet post-processing apparatus supplies a cover sheet. A plurality of paper feed devices including a paper tray, a paper feed device for feeding the cover paper, and a paper remaining amount detection device are provided, and the size of the cover paper stored in the paper feed trays of a plurality of stages is detected. When the remaining paper amount detection means of one of the paper feeding devices detects the absence of cover paper in the paper feeding tray, the control means for controlling the paper feeding means has a paper size detection means. A sheet post-processing apparatus characterized by comparing the sizes of cover sheets by a detection unit and selecting whether to permit or prohibit the continuation of the sheet feeding operation by the sheet feeding unit of the other sheet feeding device.

(3) image writing means, image processing section,
An image forming apparatus including an image forming unit and a sheet conveying unit,
An image forming system comprising the sheet post-processing device according to (1) or (2) above.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a sheet post-processing apparatus (hereinafter referred to as a post-processing apparatus) of the present invention and an image forming apparatus equipped with the post-processing apparatus will be described with reference to the drawings.

[Image Forming System] FIG. 1 is an overall configuration diagram of an image forming system including an image forming apparatus A, an image reading apparatus B, and a post-processing apparatus FS.

[Image Forming Apparatus] In the image forming apparatus A, a charging unit 2, an image exposing unit (image input unit) 3, a developing unit 4, a transfer unit 5A, and a discharging unit 5 are provided around a rotating image carrier 1.
The image forming unit includes B, the separation claw 5C, and the cleaning unit 5D.

The image of the document placed on the document table is read by the optical system of the image reading device B. The signal photoelectrically converted by the CCD image sensor is subjected to analog processing, A / D conversion, shading correction, image compression processing, etc. in the image processing section 6, and then sent to the image exposure means 3.

The charging means 2 uniformly charges the surface of the image carrier 1. In the image exposure means 3, the output light from the semiconductor laser is subjected to exposure scanning on the image carrier 1 of the image forming portion based on the image data read from the original to form a latent image. The latent image is reversely developed by the developing means 4 to form a toner image on the image carrier 1.

On the other hand, the recording paper (hereinafter referred to as paper) S fed from the paper storage means 7A is sent to the transfer position. At the transfer position, the toner image is transferred onto the paper S by the transfer means 5A. After that, the charge on the back surface of the sheet S is erased by the charge removing unit 5B, separated from the photoconductor 1 by the separation claw 5C, and conveyed by the intermediate conveyance unit 7B.
Subsequently, it is heated and fixed by the fixing means 8 and discharged from the paper discharge section 7C.

When images are formed on both sides of the paper S,
The sheet S heated and fixed by the fixing means 8 is branched from the normal sheet discharge path by the conveyance path switching plate 7D, and is switched back by the reversal conveyance means 7E to reverse the front and back,
The paper is discharged to the outside of the apparatus by the paper discharge unit 7C. The paper S discharged from the paper discharge unit 7C is sent to the receiving unit 11 of the post-processing device FS.

On the other hand, the surface of the image carrier 1 after image processing is
The developer remaining on the surface is removed by the cleaning unit 5D downstream of the separation claw 5C to prepare for the next image formation.

An operation unit 9 for selecting and setting an image forming mode and a sheet post-processing mode is arranged on the upper front side of the image forming apparatus A.

On the upper part of the image forming apparatus A, an image reading apparatus B equipped with an automatic original feeding apparatus of a moving original reading type is installed.

[Post-Processing Device] FIG. 2 is a cross-sectional view showing the conveying path of the sheet S in the post-processing device FS according to the present invention. FIG. 3 is a cross-sectional view of the punching means 40, the shift means 50, and the paper discharge means 60 that are arranged substantially horizontally in the middle stage of the post-processing device FS.

In the post-processing device FS, the first sheet feeding device 20A, the second sheet feeding device 20B, and the fixed sheet discharging table 30 are arranged in the upper stage of the drawing, and the punching means 40, the shift means 50, and the sheet discharging means are arranged in the middle stage. 60 are arranged in series on the same plane which is almost horizontal,
Stapling means (stapling means) 70 and folding means 80 in the lower stage
Are arranged in series on the same plane forming an inclined surface.

Further, on the left side surface of the post-processing device FS in the drawing,
Elevating and discharging tray 91 for stacking shift-processed sheets and edge-stitched sheet bundles, and fixed sheet-discharging tray 9 for stacking processed sheet bundles folded in three or two.
2 and are arranged.

In the post-processing apparatus FS, the receiving section 11 for the sheet S carried out from the image forming apparatus A is the sheet discharging section 7 of the image forming apparatus A.
The position and height are adjusted so that it matches C.

In the receiving section 11, the sheet S subjected to the image forming process from the image forming apparatus A, the cover sheet (cover sheet) K1 supplied from the first sheet feeding apparatus 20A, and the second sheet feeding apparatus 20B are supplied. The cover sheet (cover sheet) K2 is introduced.

A sensor PS for detecting passage of the leading edge of the sheet S is arranged near the receiving section 11.

Cover Paper Feeding Device The first paper feeding device 20A includes a paper feeding tray 21A for accommodating the cover paper K1 and a paper feeding means 22A for feeding the cover paper K1.
It consists of and. The second sheet feeding device 20B includes a sheet feeding tray 21B that stores the cover sheet K2, and a sheet feeding unit 22B that sends out the cover sheet K2.

The sheet feeding means 22A has a sheet size detecting means 26A for detecting the size of the cover sheet K1 contained in the sheet feeding tray 21A, and the remaining amount of the cover sheet K1 contained in the sheet feeding tray 21A. Remaining Paper Detecting Means 2
7A is arranged. Similarly, the paper feeding means 22B also has a paper size detecting means 26B and a paper remaining amount detecting means 27.
B is arranged.

Each of the paper feed trays 21A and 21B can accommodate about 300 sheets of cover paper K1 (or K2) made of 64 g / m ² plain paper (commonly called 55 kg paper). Also, a thick letter of 128 g / m ² (commonly known as 110 kg
The cover sheet K1 (or K2) made of paper can accommodate about 200 sheets.

The cover sheet K1 stored in the sheet feeding tray 21A of the first sheet feeding device 20A is separated and fed by the sheet feeding means 22A, and is nipped by the conveying rollers 23, 24 and 25, and the receiving section 11 is provided. Will be introduced to. In addition, the second sheet feeding device 20
The cover sheet K2 stored in the B sheet feed tray 21B is
The feeding roller 22B separates and feeds the sheet, and the conveying roller 2
It is sandwiched between 4, 25 and introduced into the receiving section 11. Hereinafter, the cover sheets K1 and K2 are also referred to as cover sheets K.

The post-processing apparatus FS is the image forming apparatus A.
The sheet S discharged from the first sheet feeding device 20A,
An online mode in which cover sheets K fed by the second sheet feeding device 20B are overlapped to perform binding processing, folding processing, and the like, and sheets S are stored in the first sheet feeding device 20A and the second sheet feeding device 20B. It is possible to switch between the offline mode and the offline mode in which the sheet is fed and fed, and the binding process and the folding process are performed.

A perforating means 40 is arranged on the downstream side of the perforating means receiving section 11 in the sheet conveying direction. The punching means 40 includes a disc 41 that is driven to rotate by a motor M as a drive source, a crank 42 that has one end locked at an eccentric position of the disc 41, a punch 43 that is driven up and down by the crank 42, and a blade portion of the punch 43. Has a die 44 that fits in the. A transport roller 45 is disposed upstream of the punching position by the punch 43 and the die 44 in the sheet transport direction, and a transport roller 46 is disposed downstream of the punching position in the sheet transport direction.

FIG. 4 is a plan view of the sheet S punched by the punching means 40. The figure shows an example (two-hole file) in which two holes h are formed near the side edge a of the paper S.

Paper branching means A paper branching means composed of switching gates G1 and G2 is provided on the downstream side of the punching means 40 in the paper carrying direction.
The switching gates G1 and G2 are selectively driven by driving a solenoid (not shown) to one of the three paper conveyance paths, that is, the first conveyance path for discharging the upper stage, the second conveyance path in the middle stage, and the third conveyance path in the lower stage. Branch.

Simple paper discharge When this paper transportation is set, the switching gate G1 shuts off the second transportation path and the third transportation path and opens only the first transportation path.

The sheets S passing through the first transport path are nipped by the transport rollers 31 and ascended, discharged by the discharge rollers 32, placed on the fixed sheet discharge tray 30, and sequentially stacked. When the sheet S is punched, the punching means 4 is used.
0 works.

The fixed paper discharge table 30 is configured so that a maximum of about 200 sheets S can be stacked.

Shift processing When this transport mode is set, the switching gate G1 is retracted upward, the switching gate G2 shuts off the third transport path, and opens the second transport path, thereby switching the sheet S. It passes between the gates G1 and G2.

The image-formed sheet S discharged from the image forming apparatus A, the cover sheet K1 fed from the first sheet feeding apparatus 20A, or the cover sheet fed from the second sheet feeding apparatus 20B. K2 passes through the intermediate paper passage of the switching gates G1 and G2, is subjected to shift processing by the shift means 50 in the direction orthogonal to the paper transport direction, and is transported by the transport rollers 51.

The shift means 50 carries out a shift process for changing the discharge position of the paper S in the carrying width direction for every predetermined number of sheets. The shift-processed sheets S are discharged by the sheet discharging unit 60 to the up-and-down sheet discharge tray 91 outside the machine and sequentially placed. The elevating and discharging tray 91 is configured to sequentially descend when discharging a large number of sheets S, and a maximum of about 3000 sheets (A4, A4
It is possible to store the sheet S of B5).

Binding Process FIG. 5 is a sectional view of the post-processing unit 10 including the binding unit 70 and the folding unit 80.

When the binding process or the folding process is set in the operation section 9, the image-formed sheet S which has been subjected to the image forming process in the image forming apparatus A and sent to the receiving section 11 of the post-processing apparatus FS is After passing through the punching means 40, it is sent to the third transport path below the switching gate G2, is sandwiched by the transport rollers 12, and is transported downward.

When the first sheet S having a size larger than A4 and B5 is conveyed in the third conveying path, the solenoid SD is driven and the sheet S is changed over to the switching gate G3.
Passing through the sheet passing path 13A on the left side of FIG.
It is pinched by and conveyed downward. The sheet S is further sandwiched by the registration rollers 15 on the further downstream side and sent out, and is ejected to the space above the intermediate stacker 71 that is inclined,
It contacts the upper surface of the intermediate stacker 71 or the sheets S stacked on the intermediate stacker 71 and is conveyed obliquely upward.

The rear end of the sheet S in the traveling direction is the transport roller 14.
After being discharged from the nipping position of the sheet S, the sheet S is turned downward by its own weight, is conveyed on the inclined surface of the intermediate stacker 71, and is a movable stopper member for end binding in the vicinity of the binding unit 70 (hereinafter referred to as an end binding stopper). ) The sheet S abutting surface of 72 abuts the rear end of the sheet S and stops.

A movable switching gate G3 is provided in order to efficiently and continuously convey small size sheets S such as A4 and B5 sizes in the third conveying path to improve copy productivity.
And a sheet passage 13B parallel to the sheet passage 13A on the left side of the switching gate G3 in the figure.

When the solenoid SD connected to the switching gate G3 is driven, the paper path 13A is closed and the paper path 1 is closed.
Open 3B.

The leading end of the first small-sized sheet S sent out from the conveying roller 12 passes through the sheet passing path 13B and comes into contact with the peripheral surface of the registration roller 15 in the rotation stopped state and stops.

Next, the solenoid SD is de-energized, the tip of the switching gate G3 swings clockwise,
The paper passage 13B is closed and the paper passage 13A is opened. The leading end of the second sheet S sent out from the transport roller 12 passes through the sheet passing path 13A, comes into contact with the peripheral surface of the registration roller 15 in the rotation stopped state, and stops. Therefore, the first sheet S and the second sheet S
The leading ends of the first sheet S are overlapped and stopped, and a standby state is set.

At a predetermined timing, the registration roller 15 is driven and rotated, and the two sheets S are nipped and conveyed at the same time and discharged onto the intermediate stacker 71. After the 3rd one,
The registration rollers 15 discharge the sheets S one by one.

Reference numeral 73 denotes a pair of width matching members movably provided on both side surfaces of the intermediate stacker 71. The width aligning member 73 is movable in a direction orthogonal to the paper transport direction,
When the sheet is conveyed to the intermediate stacker 71, the sheet is opened wider than the sheet width, and when the sheet is conveyed on the intermediate stacker 71 and comes into contact with the end binding stopper 72 and stops, the side edge of the sheet S in the width direction is lightened. The sheets S are hit to align the width (width matching). At this stop position, when a predetermined number of sheets S are stacked and aligned on the intermediate stacker 71, the binding unit 70 performs the binding process, and the sheets S are bound.

A cutout portion is formed in a part of the sheet stacking surface of the intermediate stacker 71, and a plurality of discharge belts 74C wound around a drive pulley 74A and a driven pulley 74B.
Is rotatably driven. A discharging claw 74D is formed integrally with a part of the discharging belt 74C, and the tip end portion thereof draws an elliptical locus as indicated by a dashed line in the drawing. The bound paper S is held by the discharge pawls 74D of the discharge belt 74C at the rear end of the paper S, placed on the discharge belt 74C, and slides on the mounting surface of the intermediate stacker 71 to be obliquely upward. It is pushed up and advances to the position where the discharge roller 61 of the discharge unit 60 is held. The paper S sandwiched by the rotating discharge rollers 61 is discharged and stacked on the elevating paper discharge tray 91 (see FIG. 3).

Edge Stitching Processing FIG. 6A is a plan view of the binding means 70 which performs staple binding processing by tapping the staples SP at two centrally distributed locations in the vicinity of the side edge a of the sheet bundle Sa, and FIG. FIG. 6B is a plan view of the binding unit 70 that staples the binding needle SP at one location near the corner of the sheet bundle Sa and performs the edge binding process.

The binding means 70 has a two-part structure of a stapling mechanism 70A and a staple receiving mechanism 70B, and a sheet passage 75 through which the sheet S can pass is formed in the middle thereof (see FIG. 5).

Two sets of the binding means 70 are arranged in a direction orthogonal to the sheet conveying direction, and are moved in a direction orthogonal to the sheet conveying direction by a driving means (not shown) so that the cover sheet K and all the pages of the sheet S are separated. The staples SP are struck at two centrally distributed locations in the sheet width direction of the formed sheet bundle Sa. Also, the binding means 70
Is rotatably supported and hits the binding needle SP at one corner of the sheet bundle Sa corresponding to the sheet size.

Saddle Stitching Process FIG. 6C is a plan view of the stapling means 70 for performing the saddle stitching process by stapling the stapling needles SP at two locations in the central portion of the sheet bundle Sa in the transport direction, which are distributed in the center in the sheet width direction. is there.

The binding means 70 strikes the binding needle SP at two centrally distributed portions in the paper width direction at the fold c at the center of the sheet bundle Sa in the transport direction (saddle stitching process).

When the saddle stitching mode is set, the stitching means 7
The end stapling stopper 72 near the 0 stapling position (stitching position of the stapling needle) retracts from the transport path, and at the same time, a movable stopper member for both saddle stitching and center folding (hereinafter referred to as saddle stitching center folding stopper) is located downstream thereof. 76 moves in the direction of the extension surface of the paper passing path 75 and blocks the paper passing path 77 (see FIG. 5).

The saddle-stitching stopper unit having the saddle-stitching and center-folding stopper 76, when the size (length in the transport direction) of the cover sheet K and the sheet S is set or detected, the lower edge of the sheet S to be saddle-stitched. It moves to the position where it abuts the section and stops.

After the cover sheet K is placed at the predetermined stop position on the intermediate stacker 71, the sheet S carried out from the image forming apparatus A passes from the receiving section 11 of the post-processing apparatus FS to the third conveying path. Then, the cover sheets K placed on the intermediate stacker 71 are sequentially stacked on the upper surface of the cover sheet K, and the leading ends of the sheets S are brought into contact with the saddle stitching and center folding stopper 76 to be positioned.

After the final sheet S is positioned and placed on the intermediate stacker 71, a saddle stitching process is performed by the binding means 70 on the sheet bundle Sa including the cover sheet K and all the pages of the sheet S.
By this saddle stitching process, the binding needle SP is driven into the central portion of the sheet bundle Sa in the transport direction. The staple SP is driven from the staple driving mechanism 70A on the staple driving side toward the staple receiving mechanism 70B on the staple clinching side.

.Folding processing FIG. 7 is a front view of the folding means 80.

After saddle stitching processing, saddle stitching center folding stopper 76
Moves linearly in the downstream direction of the sheet bundle Sa, and opens the downstream path of the paper passage 75. The movable saddle-stitching center-folding stopper 76 regulates the stop position of the sheet bundle Sa at the time of the saddle-stitching process at the upper position, and regulates the stop position of the sheet bundle Sa at the time of the center-folding process at the lower position.

A sheet bundle Sa consisting of the cover sheet K subjected to saddle stitching and all pages of the sheet S has a guide plate (frame) diagonally downward.
81 is guided and conveyed, and saddle stitching center folding stopper 76
The end of the sheet S in the transport direction comes into contact with and stops at a predetermined position. The saddle-stitching and center-folding stopper 76 can be moved to a predetermined position by the result of setting or detecting the sheet size and the driving unit.

The intermediate stacker 71 on the upstream side and the sheet passages of the guide plate 81 on the downstream side, which form the sheet conveying path of the post-processing unit 10, are formed in substantially the same plane, and
It forms a steep slope of ~ 30 degrees.

A projecting plate 82 of the folding means 80 is installed at the central portion of the stopped sheet S in the transport direction, that is, on the right side of the center folding position in the figure. A pair of first folding rollers 83 and 84 are installed on the left side of the middle folding position in the figure. The surfaces of the first folding rollers 83, 84 are made of a high friction resistance material such as rubber.

The folding means 80 is composed of a projecting plate 82, first folding rollers 83 and 84, a discharging means and the like.

FIG. 8 is a cross-sectional view showing a process of folding in half by the folding means 80, and FIG.
2 shows a state in which the sheet bundle Sa is pressed and brought into pressure contact with the first folding rollers 83, 84. FIG. 8B shows the protruding plate 82.
Shows a state in which the sheet bundle Sa has entered the position beyond the holding position of the first folding rollers 83 and 84 and the sheet bundle Sa has been folded in half. In FIG. 8C, the protruding plate 82 has the first folding rollers 83, 8
The sheet bundle Sa that has been folded in half is retracted from the nipping position of No. 4 and returns to the initial position, and the first folding rollers 83, 8
4 shows the state of being discharged.

In response to the double-folding process start signal, the protrusion plate 82 connected to the drive source protrudes leftward in the drawing from the sheet mounting surface. The protruding plate 82 has a thin knife shape,
Its tip makes an acute angle.

The front end of the protrusion plate 82 that projects straight to the left in the drawing pushes in the central portion of the sheet bundle Sa composed of the cover sheet K and the sheet S, and is rotated by the first bundle by the sheet bundle Sa. The nip portions of the rollers 83 and 84 are spread apart and separated from each other.

After the tip of the ejecting plate 82 has passed the sandwiching portion of the first folding rollers 83, 84, the ejecting plate 82 retracts, and the central portion of the sheet bundle Sa has the first folding rollers 83, 84.
It is pinched by and the fold c is formed. The fold c substantially coincides with the driving position of the staple SP on the sheet bundle Sa by the saddle stitching process.

The first folding rollers 83, 84 are composed of a pair of left and right pressing means having a substantially symmetrical shape. One pressing unit is connected to a drive source and driven by the first folding roller 83.
And a support plate 832 that rotatably supports the first folding roller 83 and that can swing around a support shaft 831, and is locked at one end of the support plate 832 to hold the first folding roller 83 in the nipping position direction. And a spring 833 that biases the spring. The first folding roller 84 is substantially symmetrical to the first folding roller 83, and includes a support shaft 841, a support plate 842, and a spring 843.

Sheet bundle S that is pinched to form a fold c
The sheet a is carried out along the guide member by the pair of first folding rollers 83 and 84 which are driven to rotate, and the fixed sheet discharge table 92 outside the machine.
Placed on top.

FIG. 9 is a schematic diagram showing the conveyance path of the cover sheets K1, K2 and the sheet S, the saddle stitching and folding process of the sheet bundle Sa consisting of the cover sheet K1 (or K2) and the sheet S. FIG. 10A is a perspective view of a sheet bundle Sa that has undergone saddle stitching and half-folding post-processing, and FIG. 10B shows a perspective view showing a state in which the post-processed sheet bundle Sa has been opened. 8B is a schematic cross-sectional view of the post-processed sheet bundle Sa.

On the paper feed tray 21A of the first paper feeder 20A, the cover paper K1 is on the first side (first page p1 and eighth page p1).
8) is placed with the upper side. The cover sheet K1 fed by the sheet feeding means 22A from the first sheet feeding device 20A is conveyed through the punching means 40 and the third conveying path, and is placed on the intermediate stacker 71 on the first surface (p1, p8). Placed with the bottom side. Cover sheet K stored in the second sheet feeding device 20B
Even when the sheet 2 is fed by the sheet feeding unit 22B, it passes through the punching unit 40 and the third conveyance path and is placed on the intermediate stacker 71 with the first surface (p1, p8) facing downward. .

Next, the image-formed sheet S carried out from the image forming apparatus A has a first surface (third page p3 and sixth page p3).
6) is placed on the lower side and introduced into the post-processing device FS. The sheet S is conveyed from the receiving section 11 through the punching means 40 to the third conveying path, and is placed on the cover sheet K placed on the intermediate stacker 71 with the first side thereof facing down. .

The cover sheet K and the sheet S are aligned on the intermediate stacker 71, and the binding means 70 drives the binding needle SP to perform the saddle stitching process.

In the saddle-stitched sheet bundle Sa, the sheet S has the first surface (p3, p6) on the upper side, and the cover sheet K1 thereon.
Is placed with the first surface (p1, p8) facing upward.

Next, the pushing-up operation of the ejection plate 82,
By the driving rotation of the first folding rollers 83 and 84, the sheet is folded in two and conveyed, and is discharged onto the fixed paper discharge tray 92 outside the machine.

The sheet bundle Sa created by the saddle-stitching process and the half-folding process has the first surface (p1, p8) of the cover sheet K facing outward, the second surface (p2, p7) on the back surface side, and further. Inside of it, the first side (p3, p6) of the sheet S, which is the content,
The second surface (p4, p5) of the paper S is arranged inside thereof,
As shown in the figure, the page bundle of the sheet bundle Sa consisting of 8 pages (p1 to p8) can be aligned.

When the booklet creation auto mode is selected and set on the operation section of the image forming apparatus A, the cover sheet K1 is stacked on the first sheet feeding apparatus 20A, and printing is started, the control section of the image forming apparatus A causes The above-mentioned image process is executed, and the sheet S carrying the image is subjected to saddle-stitching processing and half-folding processing by the post-processing device FS to continuously create and discharge the sheet bundle Sa.

In the operation section of the post-processing apparatus FS, the booklet making manual mode is selected and set, and the second sheet feeding apparatus 20 is set.
When the cover sheet K and the sheet S for which one image has been formed by another image forming means are stacked on B and the feeding operation is started, the control unit of the post-processing device FS separates the cover sheet K1 and the sheet S from each other. The post-processing apparatus FS performs saddle stitching processing and half-fold processing to create and eject one sheet bundle Sa.

In the present embodiment, the folding means 80 is arranged along the paper path having the same inclination as the intermediate stacker 71 which constitutes the binding means 70.

The folding means 80 shown in FIG.
It has a first folding means for folding the paper in two and a second folding means for folding the paper S in three, and can execute two modes of the half folding processing and the three folding processing.

The first folding means is the first folding roller 8
3, 84 and the protruding plate 82. The second folding unit includes a second folding roller 85, a conveyance belt 86, a conveyance switching member 87, a guide plate 88, and a sheet leading end stop member 89.

[Feeding Control of Cover Sheet] FIG. 11 is a block diagram showing the control of the image forming apparatus A and the post-processing apparatus FS.

Image exposure means 3, image forming section (2, 4, 5A, 5B, 5C, 5D) of image forming apparatus A, image processing section 6
Are controlled by the main control means 100 based on the signals selected and set by the operation unit 9.

The communication means 101 of the main control means 100 of the image forming apparatus A and the post-processing control means 200 of the post-processing apparatus FS.
The communication means 201 is electrically connected, and control signals are mutually exchanged.

The post-processing device F is selected by the selection means of the operation unit 9.
S sheet feeding by the first sheet feeding device 20A and the second sheet feeding device 20B, punching processing by the punching means 40, edge binding, side stitching, saddle stitching processing by the binding means 70, center folding by the folding means 80, three Each processing of folding is set.

With this setting, the main control means 100 sends a control signal to the post-processing apparatus FS via the communication means 101.
The control signal is sent to the post-processing control means 20 via the communication means 201.
Transmitted to 0. The post-processing control means 200 drives each of the connected means.

When cover sheet feeding, cover sheet size, sheet size, edge stitching, saddle stitching, center folding, and punching are selected by the operation unit 9, the post-processing control means 200 causes the image forming apparatus A to perform printing.
Each processing of cover sheet paper feeding, edge binding, saddle stitching, center folding, punching, and sheet transportation is executed in accordance with the sheet size of the sheet S discharged from the post-processing apparatus FS.

FIG. 12A shows a user setting screen of the operation unit 9 of the image forming apparatus A. FIG. 12B shows a paper feed tray automatic selection setting screen.

Select "applied function" on the operation unit 9 and select the "user setting" function to open the user setting screen shown in FIG. 11. The function of "automatic setting of paper feed tray" of 11 is selected.

12B, a sheet feed tray automatic selection setting screen is opened, and in the presence or absence of automatic selection, either "with automatic switching" or "without automatic switching" is selected and set. . When automatic switching is selected, automatic switching of the paper feed trays 21A and 21B is permitted. If no automatic switching is selected, the paper feed trays 21A, 2A
Automatic switching of 1B is prohibited.

FIG. 13 is a flow chart showing the paper feed control of cover sheets K1 and K2. (1) The cover unit automatic paper feed mode is set on the operation unit 9.

(2) In the image forming apparatus A, the copy operation is started. (3) The cover sheet K1 is fed from the sheet feeding tray 21A of the first sheet feeding device 20A, is superposed on the sheet S discharged from the image forming apparatus A, and the end binding process is performed on the sheet bundle Sa with the cover sheet. Alternatively, saddle stitching and center folding processing is performed in the online mode.

(4) The remaining paper amount detecting means 27 indicates that there is no cover paper K1 stored in the paper feed tray 21A.
A detects.

(5) When "with automatic switching" is set, the remaining sheet amount detecting means 27B detects that the cover sheet K2 is stored in the sheet feeding tray 21B, and the post-processing control means 200 The size detection signal of the cover sheet K1 stored in the sheet feed tray 21A by the sheet size detection unit 26A and the size detection signal of the cover sheet K2 stored in the sheet feed tray 21B by the sheet size detection unit 26B match. If it is determined that they coincide with each other, the automatic paper feed switching is permitted, and after the paper feed of the paper feed tray 21A is completed, the cover sheet K2 stored in the paper feed tray 21B is
Is fed by the paper feeding device 22B, and the copy operation by the image forming apparatus A is continued.

(6) The remaining paper amount detecting means 27 indicates that the cover paper K1 stored in the paper feed tray 21A is completely exhausted.
When A is detected, but “no automatic switching” is preset, the copy operation by the image forming apparatus A is stopped.

(7) The size detection signal of the cover sheet K1 stored in the sheet feed tray 21A by the sheet size detection means 26A and the size detection signal of the cover sheet K2 stored in the sheet feed tray 21B by the sheet size detection means 26B. When the control means 100 compares and judges that the and do not match,
The feeding of the cover sheet is stopped, and the copy operation by the image forming apparatus A is stopped.

(8) Cover sheet K1 is placed in the sheet feeding tray 21A.
When the sheet is replenished, the sheet feeding means 22A is operated to start feeding the cover sheet K1 and restart the copy operation by the image forming apparatus A.

[0103]

The post-processing apparatus and the image forming system of the present invention have the following effects.

In the post-processing apparatus having a plurality of stages of sheet feeding devices including a sheet feeding tray for storing cover sheets, a sheet feeding unit for feeding cover sheets, a sheet size detecting unit, and a sheet remaining amount detecting unit, any one of the sheet feeding units is provided. If the paper tray is also loaded with cover paper or paper of the same size, as soon as there is no more cover paper or paper stored in the paper feed tray that is currently feeding paper, cover paper stored in another paper feed tray. Alternatively, by automatically feeding the paper, the post-processing with high copy productivity can be performed at high speed without interrupting the copy operation.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an image forming system including an image forming apparatus, an image reading apparatus, and a post-processing apparatus.

FIG. 2 is a cross-sectional view showing a sheet conveyance path in the post-processing apparatus.

FIG. 3 is a cross-sectional view of punching means, shift means, and paper discharge means.

FIG. 4 is a plan view of a sheet that has been punched by punching means.

FIG. 5 is a sectional view of a post-processing unit including a binding unit and a folding unit.

FIG. 6 is a plan view of a binding unit that performs side stitching processing, a plan view of a binding unit that performs edge binding processing, and a plan view of a binding unit that performs saddle stitching processing.

FIG. 7 is a front view of a folding unit.

FIG. 8 is a cross-sectional view showing a process of folding in half by a folding unit.

FIG. 9 is a schematic diagram illustrating a cover sheet, a sheet conveyance path, a saddle stitching process of a sheet bundle, and a folding process.

FIG. 10 is a perspective view of a sheet bundle that has undergone saddle stitching and half-folding post-processing, a perspective view showing a state in which the post-processed sheet bundle is opened, and a schematic cross-sectional view of the post-processed sheet bundle.

FIG. 11 is a block diagram showing control of the image forming apparatus and the post-processing apparatus.

FIG. 12 is a user setting screen of the operation unit of the image forming apparatus,
And the paper tray automatic selection setting screen.

FIG. 13 is a flowchart showing a paper feed control for a cover sheet.

[Explanation of symbols]

9 Operation part 20A first paper feeding device 20B second paper feeding device 21A, 21B paper feed tray 22A, 22B paper feeding means 26A, 26B Paper size detecting means 27A, 27B Paper Remaining Amount Detection Means 70 binding means (stapling means) 80 folding means 100 main control means 200 Post-processing control means A image forming apparatus FS paper post-processing device (post-processing device) K, K1, K2 cover sheet (cover sheet) S recording paper (paper) Sa paper bundle

Continued front page    F-term (reference) 2H072 AA12 AA23 AA27 AA31 AB04                       AB18 GA08                 3F108 AA01 AC02 AC03 BA03 CD01                       GA02 GA04 GB01 GB03 HA02                       HA33 HA36 HA39 HA46                 3F343 FA01 FB01 GA02 GB01 GC01                       GD01 HC02 HC11 HC28 KB04                       MA03 MA09 MA23 MA24 MA26                       MB03 MB13 MC21 MC23

Claims (3)

[Claims] 1. A sheet post-processing apparatus in which recording sheets discharged from an image forming apparatus are sequentially sent to a stacking unit and post-processed by a post-processing unit.
A plurality of sheet feeding devices including a sheet feeding tray for storing cover sheets, a sheet feeding unit for feeding the cover sheets, and a sheet remaining amount detecting unit are provided, and the cover sheets of the same size are provided in the plurality of sheet feeding trays. If the remaining paper amount detecting means of one of the paper feeding devices detects that there is no cover paper in the paper feeding tray, the control means for controlling the paper feeding means controls the other paper feeding device. A sheet post-processing apparatus, characterized in that a sheet feeding device of the apparatus is operated to start a sheet feeding operation of a cover sheet by the other sheet feeding apparatus, following a sheet feeding operation of the one sheet feeding apparatus. 2. A sheet post-processing apparatus in which recording sheets discharged from an image forming apparatus are sequentially sent to a stacking unit and post-processing is performed by a post-processing unit.
A cover sheet accommodated in a plurality of stages of the sheet feed tray, which is provided with a plurality of stages of a sheet feed device including a sheet feed tray for storing cover sheets, a sheet feed unit for feeding the cover sheets, and a sheet remaining amount detection unit. It has a paper size detection means to detect the size of the paper,
When the remaining paper amount detecting means of one of the paper feeding devices detects the absence of cover paper in the paper feeding tray, the control means for controlling the paper feeding means controls the size of the cover paper by the paper size detecting means. In comparison, a sheet post-processing apparatus characterized by selecting whether to permit or prohibit the continuation of the sheet feeding operation by the sheet feeding means of the other sheet feeding device. 3. An image forming apparatus comprising an image writing unit, an image processing unit, an image forming unit, and a sheet conveying unit, and the sheet post-processing apparatus according to claim 1 or 2. Image forming system.