JP2010247956A - Sheet postprocessing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem of becoming unable to slip out when hands and fingers of an operation worker enter, since the hands and the fingers of the operation worker easily enter the inside of an opening of a sheet carrying means. <P>SOLUTION: In this sheet postprocessing device, when loading a sheet on a processing tray 29, a first toller 26a rises up to a first height, and the sheet is loaded between the first roller 26a ad a fixed second roller 26b and on the processing tray 29. When predetermined processing by a processing means 31 is not applied to the loaded sheet, when detecting that the first roller 26a rises to a second height or more, a control means 160 stops at least the processing means. When applying the predetermined processing by the processing means 31 to the loaded sheet, when detecting that the first roller 26a rises to a third height or more, the control means 160 stops at least the processing means. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a sheet post-processing apparatus that performs processing on a sheet.

  The sheet post-processing apparatus has a configuration as shown in FIG. For example, the sheet post-processing apparatus B is used by being connected to the image forming apparatus A shown in FIG. The sheet post-processing apparatus B receives a sheet such as a recording medium on which an image is formed from the image forming apparatus or the like, and then stacks the processing tray 29 on which the sheet is stacked, and the sheets stacked on the processing tray 29 in a bundle And a sheet conveying unit 26 that conveys the sheets processed by the edge binding unit 31 to the stack tray 21. The sheet conveying means 26 includes a first roller 26a (switchback roller) that is movable in the vertical direction and a second roller 26b that is provided at a position facing the switchback roller 26a and adjacent to the processing tray 29. (Fixed roller) and height detecting means (microswitch) for detecting the height of movement of the first roller 26a. Controls such as vertical movement of the switchback roller 26a and stapling operation are controlled by a control means (post-processing control unit).

The stapling operation performed by the end binding unit 31 is performed after a sheet such as a recording medium received on the processing tray 29 is transported by the sheet transport unit 26, guided to the sheet end regulating unit, and the sheet bundle is aligned. A stapling operation is performed.
The opening formed between the switchback roller and the fixed roller is changed by the above-described vertical movement of the switchback roller 26a.

When the sheets are stacked on the processing tray 29, the switchback roller 26a rises to the first height, and the sheets are stacked between the switchback roller 26a and the fixed roller 26b and on the processing tray 29. When a hand or finger enters the opening of the sheet conveying means while the sheets are being stacked or during stapling by the end binding unit 31, the first roller 26a is higher than the first height, Rise above the height of. The post-processing control unit is configured to stop the operation of the sheet post-processing apparatus when the height detection unit detects that the height has risen above the second height.

JP 2006-82153 A JP 05-169396 A

  However, in recent years, the maximum number of sheets to be stapled by the stapling means has been greatly increased (for example, 100 sheets at the maximum) compared to the conventional technique (for example, 100 sheets at the maximum), and the sheet conveying means is configured corresponding to the increase. The height of the opening formed between the switchback roller 26a and the fixed roller 26b on the lower side is also greatly increased as compared with the prior art. When such a large opening height is provided, the operator's hand and fingers can easily enter the opening, and there is a risk that the operator's hands and fingers will not enter and cannot be removed. is there.

  Accordingly, the present invention provides a configuration in which the operation is stopped when the first roller is raised above the second height due to an operator's hand or finger entering the opening of the sheet conveying means. When processing the sheet by the processing means, when the height detecting means detects that the first roller has risen above the third height different from the second height, the control means An object of the present invention is to provide a sheet post-processing apparatus that stops at least the processing means.

  In order to achieve the above object, a first invention according to the present application is directed to a processing tray for stacking sheets to be processed, processing means for processing the sheets stacked on the processing tray, and transporting the sheets to the processing tray. Sheet conveying means, control means for controlling the processing means and the sheet conveying means, the sheet conveying means being fixed at a position facing the first roller and a first roller movable in the vertical direction. Provided by a second roller adjacent to the processing tray and a height detecting means for detecting a height of movement of the first roller. When stacking sheets on the processing tray, the first roller A roller is raised to a first height, and a sheet is stacked between the first roller and the second roller and on the processing tray. During operation, the first roller moves from the first height. high In the sheet post-processing apparatus configured to stop the operation when the height detecting unit detects that the height has been raised to a second height, the processing unit applies a predetermined amount to the sheets stacked on the processing tray. When the height detecting means detects that the first roller has risen above a third height that is different from the first height and the second height, The control means stops at least the processing means.

  In addition, the second invention according to the present application is characterized in that the third height is lower than the first height and the second height.

  Furthermore, a third invention according to the present application is characterized in that the predetermined process is a staple process.

  Furthermore, the fourth invention according to the present application is characterized in that the height detecting means detects the height of the first roller by a micro switch.

  As described above, in the present invention, the processing operation is stopped when the sheet conveying means rises above the second height during the processing operation other than the staple binding operation, while the sheet is stopped during the staple binding operation. A configuration that stops the processing operation when the conveying means rises above the third height, or a micro that detects the height of the first roller corresponding to the second height and the third height. It is possible to adopt a configuration in which a switch is provided.

  The present invention is configured such that the height set for the sheet conveying means for stacking the sheet bundle on the processing tray is made smaller during the staple binding operation than during the operation other than the staple binding operation. Even if the height of the opening formed in the sheet conveying means is increased and the operator's hand or finger is easily placed inside the opening, the staple binding operation can be performed. Since it is configured to ensure good safety when being executed, the trailing edge alignment operation of the sheet carried on the processing tray can be performed well with a simple configuration, The reliability of the sheet post-processing apparatus and the image forming system can be significantly improved at low cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory side view showing an overall configuration of an example of an image forming system to which the present invention is applied. FIG. 2 is an enlarged side view illustrating an overall configuration of a post-processing device (sheet handling device) of the image forming system illustrated in FIG. 1. FIG. 3 is an enlarged partial cross-sectional explanatory view showing a staple unit provided in the post-processing apparatus of FIG. 2 and a structure in the vicinity thereof. It is a configuration explanatory view of the rear end regulating means and alignment means of the processing tray. It is explanatory drawing of the discharge mechanism of a processing tray, (a) is side explanatory drawing showing the structure of a switchback roller, (b) is side explanatory drawing showing the standby state of the switchback roller, (c) is switch It is side surface explanatory drawing showing the sheet engagement state of the back roller. It is a flowchart regarding the height detection operation | movement of a switchback roller. It is a flowchart at the time of changing and controlling the opening height in a switchback roller. FIG. 8 is a flowchart showing a control operation related to a high position condition in the flowchart shown in FIG. 7. FIG. 8 is a flowchart showing a control operation related to a low position condition in the flowchart shown in FIG. 7. It is explanatory drawing of the sheet aligning mechanism of a processing tray, (a) is explanatory drawing which shows the whole structure, (b) shows a state with a small sheet | seat stacking amount, (c) shows a state with a large sheet | seat stacking amount. (D) is the positional relationship between the carry-in guide and the carry-out guide, (e) shows the configuration of the kick means, and (f) is an explanatory view showing the drive mechanism. The position movement mechanism of the alignment plate in a processing tray is shown, (a) is explanatory drawing which shows the regulation state of a large size sheet (b) and a medium size sheet. FIG. 4 is a diagram illustrating a position movement mechanism of an alignment plate in a processing tray, (c) is an explanatory view showing a restricted state of a small size sheet, and (d) is an offset state of a large size sheet. It is a perspective view which shows the whole structure of a sheet bundle carrying-out means. It is explanatory drawing which shows the planar structure of a sheet bundle carrying-out means. It is explanatory drawing of the guide mechanism of a sheet bundle carrying-out means. It is explanatory drawing of the drive mechanism of a sheet bundle carrying-out means. 4A and 4B are explanatory views of a grip mechanism of the sheet bundle carrying-out means, where FIG. 4A is an explanatory view of a state where a sheet bundle is nipped, and FIG. FIG. 2 is a block diagram of a control configuration in the image forming system of FIG. 1.

  Hereinafter, an embodiment in which the present invention is applied to an image forming system provided with a sheet post-processing apparatus B in a copying machine A as an image forming apparatus will be described in detail with reference to the drawings.

[Configuration of image forming system]
The image forming system shown in FIG. 1 includes a sheet post-processing apparatus B connected to an image forming apparatus A that forms an image on a sheet-like recording medium such as a cut sheet. A carry-in port 23 of the sheet post-processing device B is connected to the paper discharge port 3 of the device A. The sheet-shaped recording medium on which an image is formed by the image forming apparatus A is configured to be stapled by the sheet post-processing apparatus B and stored in the stack tray 21 or the saddle tray 22.

[Configuration of Image Forming Apparatus]
As shown in FIG. 1, the image forming apparatus A in such an image forming system sends a sheet-like recording medium such as a cut sheet from the paper feeding unit 1 to the image forming unit 2, and the image forming unit 2. Then, after printing on the sheet-like recording medium, the sheet is discharged from the discharge port 3. The sheet feeding unit 1 stores a plurality of sizes of sheet-like recording media in the sheet feeding cassettes 1a and 1b, and feeds the designated sheet-like recording media one by one to the image forming unit 2. The image forming unit 2 includes, for example, an electrostatic drum 4, a print head (laser light emitter) 5 disposed around the electrostatic drum 4, a developing device 6, a transfer charger 7, and a fixing device 8. An electrostatic latent image is formed on the electrostatic drum 4 by the laser emitter 5, toner is attached to the developer by the developing device 6, and the image is transferred onto the sheet-like recording medium by the transfer charger 7. Heat fixing with the fixing device 8. The sheet-like recording medium on which the image is formed in this manner is sequentially carried out from the paper discharge port 3. Reference numeral 9 in FIG. 1 indicates that the sheet-like recording medium printed on the front surface side from the fixing device 8 is turned upside down via the switchback path 10, and then is fed again to the image forming unit 2 to be the back surface of the sheet-like recording medium. This is a circulation path of double-sided printing for printing on the side. The sheet-like recording medium printed on both sides in this way is turned upside down by the switchback path 10 and then carried out from the paper discharge port 3.

  The image reading device 11 is a device that scans an original sheet set on the platen 12 with a scanning unit 13 and electrically reads it with a photoelectric conversion element (not shown). The image data is digitally processed by the image processing unit, for example, and then transferred to the data storage unit 14, and an image signal corresponding to the image data is sent to the laser emitter 5. The document feeder 15 is a feeder device that feeds document sheets stored in the stack tray 16 to the platen 12.

The image forming apparatus A having the above configuration is provided with an image forming apparatus control unit (controller) 150 as shown in FIG. 18. The control panel 18 controls image forming conditions such as sheet size designation, color Print conditions such as monochrome print designation, print number designation, single-sided / double-sided print designation, enlarged / reduced print designation, and the like are set.
On the other hand, in the image forming apparatus A in FIG. 1, image data read by the scan unit 13 or image data transferred from an external network is accumulated in the data storage unit 17. The image data is transferred from the data storage unit 17 to the buffer memory 19, and data signals are sequentially conveyed from the buffer memory 19 to the laser emitter 5.

[Configuration of sheet post-processing apparatus]
The sheet post-processing apparatus B receives a sheet-like recording medium on which an image is formed from the paper discharge port 3 of the image forming apparatus A, and (i) stores the sheet-like recording medium in the stack tray 21 (print-out mode) (Ii) Sheet-like recording media from the paper discharge outlet 3 are aligned in a bundle and stapled, and then stored in the stack tray (first stack tray) 21 (binding finish mode), or (iii) paper discharge In order to align the sheet-like recording medium from the mouth 3 in a bundle and staple the center thereof, fold it into a booklet and store it in the saddle tray (second stack tray) 22 (booklet finishing mode) It is configured as follows.

  In particular, as shown in FIG. 2, the casing (apparatus frame) 20 of the sheet post-processing apparatus B is provided with a carry-in port 23a, which is a discharge port of the image forming apparatus A. 3 is connected. In the casing 20, the sheet-like recording medium from the carry-in entrance 23a is partly collected and stacked, and the sheet-like recording medium from the carry-in entrance 23a is partly accumulated. A second processing unit BX2 for finishing a booklet is provided. A first loading path P1 is provided between the first processing unit BX1 and the loading port 23a, and a second loading path P2 is provided between the second processing unit BX2 and the loading port 23a. The sheet-like recording medium from the opening 23a is distributed and guided to the first processing unit BX1 and the second processing unit BX2. The carry-in entrance 23a is provided with a carry-in roller 23, a sheet sensor S1, and a path switching means (flapper member) 24 that distributes the sheet-like recording medium to the first or second carry-in paths P1 and P2.

  A “buffer path P 3” is provided between the punch unit 60 and the processing tray 29 in the first transport path P 1. This buffer path P3 is used when a post-processing such as stapling is performed on a stack of sheet-like recording media (hereinafter referred to as a sheet bundle) that are stacked and arranged on the processing tray 29 during the post-processing operation. The subsequent sheet-like recording medium sent to 23a is temporarily retained. For this reason, the buffer path P3 is branched and arranged in the vertical direction of the casing 20 on the upstream side of the path to the processing tray 29 in the first transport path P1, as shown in FIG. The sheet-like recording medium from the first transport path P1 is switched back and stays in this path. Accordingly, when post-processing (end binding processing described later) is performed on the sheet bundle that has been aligned and stacked on the processing tray 29, the subsequent sheet-like recording medium sent to the carry-in port is temporarily retained, and the processing of the processing tray 29 is performed. After the sheet is carried out, the succeeding sheet-like recording medium in this path can be conveyed to the tray 29.

  The first carry-in path P1 is disposed substantially horizontally in the upper part of the apparatus housing constituted by the casing 20, and the first processing unit BX1 is disposed downstream of the first carry-in path P1, and the stack tray 21 is disposed downstream thereof. Is arranged. A punch unit 60 (to be described later) is disposed between the carry-in port 23 and the first processing unit BX1 in the first carry-in path P1. In the first carry-in path P1, a paper discharge roller 25 and a paper discharge outlet 25x are provided at the exit end of the path, and a paper discharge sensor S2 is disposed in the paper discharge outlet 25x, and passes through the first carry-in path P1. The sheet-shaped recording medium to be detected is detected to detect jam and to count the number of passing sheets. Then, a processing tray 29 described below is arranged with a step formed downstream of the paper discharge port 25x.

  Further, the second carry-in path P2 is arranged substantially vertically in the lower part of the casing 20, the second processing unit BX2 is arranged on the downstream side of the second carry-in path P2, and the saddle is arranged on the downstream side thereof. A tray 22 is arranged. Further, a trimmer unit (cutting unit) 90 to be described later is disposed between the second processing unit BX2 and the saddle tray 22 in the second carry-in path P2. Furthermore, a conveyance roller 27 is provided in the second carry-in path P2, and a stacking guide 45, which will be described later, is disposed with a step formed on the downstream side thereof.

[Configuration of first processing unit]
Here, the first processing unit BX1 includes a processing tray 29 disposed in the first carry-in path P1, an end binding unit 31 as a processing unit disposed in the processing tray 29, an aligning unit (alignment unit). ) 51.

[Processing tray structure]
As shown in FIG. 3, the processing tray 29 is formed of a synthetic resin plate or the like, and includes a sheet support surface 29a for stacking and supporting sheet-like recording media. The sheet support surface 29a is arranged with a step formed on the downstream side of the paper discharge port 25x, and is configured to stack and store the sheet-like recording medium from the paper discharge port 25x. The illustrated sheet support surface 29 a is formed to have a length shorter than the length of the sheet in the sheet discharge direction, supports the rear end of the sheet from the sheet discharge outlet 25 x, and the sheet front end is above the uppermost sheet of the stack tray 21. To support (bridge support).

The processing tray 29 is provided with a sheet end regulating means 32 and abuts and aligns the sheet rear end (or may be the front end) from the sheet discharge outlet 25x. Above the processing tray 29, a switchback roller (first friction rotating body; hereinafter the same) 26 (first roller) as a sheet conveying means for conveying the sheet-like recording medium carried on the tray to the sheet end regulating means 32. 26a, the second roller 26b), aligning means (alignment means) 51, and side alignment means 34 are arranged.
Each configuration will be described below.

[Configuration of sheet edge regulating means]
The processing tray 29 is provided with a sheet end regulating means 32 for positioning one end edge of the leading and trailing ends of a loaded sheet-like recording medium (hereinafter simply referred to as a sheet). The sheet end regulating means 32 shown in FIG. 4 includes a stopper member having a sheet end surface regulating surface 32a that regulates butting the trailing edge of the sheet and a sheet upper surface regulating surface 32b that regulates the upper sheet surface of the uppermost sheet. Yes. The sheet end regulating means 32 is disposed at the rear edge of the processing tray 29, and abuts and regulates the rear edge of the sheet conveyed by a switchback roller (sheet conveying means) 26 and an aligning means 51, which will be described later. The sheet is positioned at a preset post-processing position (binding position; hereinafter the same). At this time, the sheet upper surface regulating surface 32b regulates the warping surface of the sheet with the curled tip, and the sheet end surface regulating surface 32a regulates the position of the sheet edge.

  The illustrated sheet end surface regulating surface 32a and sheet upper surface regulating surface 32b are formed of a stopper member integrally formed of a resin, a metal plate, or the like, but both the regulating surfaces can be formed of individual members. In the illustrated sheet end regulating means 32, a fixed stopper member 32A is disposed at the center in the sheet width direction, and first and second movable stopper members 32B and 32C are disposed at predetermined intervals on the left and right ends of the sheet, respectively. It is comprised with the stopper member. In addition, 32s in the drawing is a leaf spring attached to each stopper member in order to correct the curl at the front end of the sheet.

  As described above, the first and second movable stopper members 32B and 32C positioned at the left and right end portions of the sheet are moved according to the sheet size. Therefore, the right slide member 38a and the left slide member 38b are fitted and supported on the bottom wall of the processing tray 29 so as to be movable in the sheet width direction. The first movable stopper member 32B and the second movable stopper member 32C are fixed to the left and right slide members 38a and 38b. The left and right slide members 38a and 38b are connected so as to be interlocked with alignment plates 34L and 34R that align the seat sides as will be described later.

  The sheet end regulating means 32 configured as described above is configured such that at least the sheet upper surface regulating surface 32b can move up and down in the sheet stacking direction. This is because when the sheet bundle on the processing tray 29 is unloaded from the tray by the sheet bundle unloading means 100 described later, the sheet bundle on the tray 29 may be lifted upward by the sheet bundle unloading means 100. This is because the sheet upper surface regulating surface 32b is moved upward following the upward movement.

  Therefore, as shown in FIG. 4, the fixed stopper member 32 </ b> A is pivotally supported by the bottom wall of the processing tray 29 so as to be swingable, and is urged and supported by the urging spring 33 downward in the drawing. The first and second movable stopper members 32B and 32C are attached to the left and right slide members 38a and 38b so as to be elastically deformable (part 32α in the drawing).

[Configuration of sheet conveying means]
The processing tray 29 is provided with a sheet conveying means (switchback roller) 26 for guiding the sheet carried from the paper discharge port 25x to the sheet end regulating means 32 described above. The sheet conveying means 26 is composed of a friction rotating body such as a roller and a belt that conveys a sheet conveyed to the processing tray 29 from the sheet discharge outlet 25x to the sheet end regulating means 32. This will be described below according to the illustrated switchback roller mechanism.

  The switchback roller 26 is arranged above the processing tray 29 as shown in FIG. 5 and is configured to convey the uppermost sheet on the processing tray 29 in the forward and reverse directions. The switchback roller 26 includes a first roller 26a as a first roller movable in the vertical direction, and a first roller 26a adjacent to the processing tray 29, which is fixedly provided at a position facing the first roller 26a. 2 rollers 26b. In the following, the first roller 26a is referred to as a switchback roller 26a, and the switchback roller 26a is in an operating position in contact with the sheet on the processing tray 29 (state shown in FIG. 5C). It is axially supported by the elevating support arm 28 so as to move up and down between the standby position (the state shown in FIG. 5B) spaced above the seat. That is, the lifting support arm 28 is supported by an apparatus frame (not shown) so as to be swingable by a swinging rotary shaft 28a. The swinging rotary shaft 28a is supported by a lift motor (arm driving means; hereinafter) via a pinion 28p. Similarly, MY is connected. The elevation support arm 28 is provided with a position sensor S3 as a height detection means for detecting the height of movement of the switchback roller (first roller) 26a, and detects the position of the elevation support arm 28. Lifting control is performed between the standby position and the operating position.

  The movable switchback roller 26a, which is axially supported by the elevating support arm 28, is connected to a forward / reverse motor (not shown) via a transmission means, and discharges the sheet carried on the processing tray 29 in the paper discharge direction and in the opposite direction. It is designed to reverse forward and backward. Therefore, the roller rotating shaft 26z of the switchback roller 26a is supported by a long groove 28u formed in the lifting support arm 28 as shown in FIG. 5A, and moves up and down in the sheet stacking direction (FIG. 5A vertical direction). The shaft is supported as possible. The movable switchback roller 26a is provided with a paper surface contact sensor Ss. Incidentally, 28z shown in the figure is a leaf spring that constantly urges the roller rotation shaft 26z downward, for preventing the malfunction of the paper surface contact sensor Ss by lifting the shaft when the switchback roller 26a is lowered.

"Paper contact sensor"
The switchback roller 26a is provided with a paper surface contact sensor Ss for detecting the position of a roller rotation shaft 26z that moves up and down along the long groove 28u. This paper surface contact sensor Ss is fixedly disposed on the above-described lifting support arm 28, and a roller rotating shaft 26z that moves (moves upward) in the long groove 28u by the contact pressure with which the switchback roller 26a contacts the uppermost sheet on the processing tray is provided. It is configured to detect a position. For this reason, the lift support arm 28 is provided with a sensor lever 30 having a rotation center o1 at a position different from the swing rotation shaft 28a, and a roller rotation shaft 26z is axially connected to the tip of the sensor lever 30. The paper surface contact sensor Ss is configured by a photo sensor that detects a sensor flag 30f formed at the rear end of the sensor lever 30.

  The switchback roller 26a configured as described above is configured such that the lifting support arm 28 is vertically swung by the lifting motor MY, and the standby position above the processing tray (FIG. 5B) and the sheet carried on the processing tray. It moves up and down with respect to the operating position (FIG. 5C) in contact with. Then, it is detected by the paper surface contact sensor Ss disposed on the elevating support arm 28 that the switchback roller 26a comes into contact with the sheet carried on the processing tray 29. The detection of the stacking height of the sheet at this time has been conventionally performed by swinging a relatively light flag-like member. For example, when the sheet is fed at a high speed or a curled portion is generated on the sheet. The flag-like member may swing more than the actual sheet stacking height and stop, which may cause an error in the detection value.

"Configuration of control means"
Therefore, the lifting control means 165 for controlling the lifting motor MY is configured as follows. The raising / lowering control means 165 is comprised by control CPU160 mentioned later, and raises / lowers the raising / lowering support arm 28 between a standby position and an operating position. First, the lift control means 165 is stopped at the standby position by a position sensor S3 disposed on the lift support arm 28. First, an initial operation for determining the current height position of the switchback roller 26a is executed.

Hereinafter, it demonstrates along the flowchart of FIG.
First, the switchback roller 26a provided on the lifting / lowering support arm 28 together with the lifting / lowering support arm 28 starts to descend (ST1), and the sheet surface contact sensor Ss for detecting the position of the roller rotation shaft 26z is turned on as described above. (ST2) Stop descent (ST3). Thereafter, the raising of the switchback roller 26a is started together with the elevating support arm 28 (ST4), and the distance (height) H0 until the paper surface contact sensor Ss is turned off is measured (ST5). The height at which the switchback roller (first roller) 26a ascends when the sheets are stacked on the processing tray 29 in this way is referred to as a “first height”.

Such measurement is repeatedly performed a plurality of times (for example, three times), an average value is calculated based on the obtained plurality of measurement values, and is determined as a measurement height H0 from the conveyance surface of the processing tray 29. And remember. Then, the measured height H0 is set as a descending amount with respect to the next first sheet. Thereafter, the switchback roller 26a is lifted to the home position together with the lifting support arm 28 to enter a standby state (ST6).

  When the first sheet is transported, the sheet sensor S2 detects the leading edge of the sheet carried out from the sheet discharge port 25x, and the sheet leading edge passes immediately below the switchback roller 26a ( ST7) The elevating motor MY is rotated counterclockwise in FIG. Then, the elevating support arm 28 rotates in the counterclockwise direction in FIG. 5A around the swing rotation shaft 28a. As a result, the roller rotating shaft 26z of the switchback roller 26a is supported by the long groove 28u, so that the switch back roller 26a is moved from the standby position (FIG. 5B) to the operating position (FIG. 5C) at substantially the same speed as the lifting support arm 28. (ST8). At this time, the sensor lever 30 connected to the switchback roller 26a moves (lowers) in the same direction at the same speed as the lifting support arm 28. Further, the switchback roller 26a at this time descends to a predetermined height calculated from the above-described measured height H0 from the tray conveyance surface (ST9).

  At this time, the raising / lowering control means 165 makes the lowering speed (rotational speed of the raising / lowering motor MY) Va of the raising / lowering support arm 28 equal to the speed (free fall speed) Vr at which the movable switchback roller 26a falls by its own weight in the long groove 28u. Or it is set so as to be later (Va ≦ Vr). This is to prevent the paper surface contact sensor Ss from malfunctioning due to rebound or the like when the descending speed Va of the lifting support arm 28 is made faster than the switchback roller 26a that freely falls in the long groove 28u. That is, the speed Vr at which the switchback roller 26a falls is limited by the speed of the lifting support arm 28 and gently lowered to prevent erroneous detection such as chattering of the paper surface contact sensor Ss.

  Next, when the peripheral surface of the switchback roller 26a contacts the uppermost sheet on the processing tray 29, the switchback roller 26a stops on the uppermost sheet (ST10), but the lifting support arm 28 swings in the same direction. Move and descend. At this time, in the paper surface contact sensor Ss, the sensor lever 30 swings in the clockwise direction (the direction indicated by the arrow in FIG. 5C) about the center rotation center o1. Then, the paper surface contact sensor Ss detects the sensor lever 30 and is turned “ON”. The lift motor MY is stopped by the detection signal of the paper surface contact sensor Ss. By controlling in this way, the switchback roller 26a always abuts on the uppermost sheet with a constant pressure contact force (for example, its own weight) Pt regardless of the amount of sheets stacked on the processing tray 29 (FIG. 5 ( c)).

  Concurrently with the lowering of the switchback roller 26a to the operating position, the elevation control means 165 drives a forward / reverse motor (not shown) to rotate the switchback roller 26a in the forward / reverse direction. Then, the sheet carried on the uppermost sheet of the processing tray 29 from the sheet discharge outlet 25x receives a certain conveyance force and is conveyed in the sheet discharge direction and the sheet discharge opposite direction. In the illustrated apparatus, when the sheet from the sheet discharge outlet 25x is conveyed in the sheet discharge direction from the sheet discharge outlet, the switchback roller 26a is rotated in the clockwise direction in the figure, and the leading end of the sheet is drawn into the processing tray 29. Then, after the rear end of the sheet has passed through the paper discharge port 25x, the switchback roller 26a is reversely rotated and conveyed back to the sheet end regulating means 32 side. During the sheet conveyance process, the sheet and the switchback roller 26a are engaged with a constant pressing force regardless of the amount of sheets stacked on the processing tray, and a predetermined conveying force set in advance is applied to the sheet. .

  Next, the switchback roller 26a starts to rise (ST11), and the distance (height) to reach a certain height (first height) position where the paper surface contact sensor Ss for detecting the position of the roller rotation shaft 26z is turned off. ) H1 is measured (ST12). Such measurement is repeatedly performed a plurality of times (for example, three times), an average value is calculated based on the obtained measurement values, and is determined as the measurement height H1 from the top surface of the stacked sheets. Remember. Then, the measured height H1 is set as a descending amount with respect to the next second sheet. Thereafter, the switchback roller 26a is raised to the home position (height 22 mm) together with the lifting support arm 28 to be in a standby state (ST13), and the second and subsequent sheets are also subjected to the same sheet by the switchback roller 26a. Transport is performed.

As described above, in the present embodiment, when the Nth sheet is conveyed, the leading edge of the sheet carried out from the discharge port 25x is detected by the sheet sensor S2, and the leading edge of the sheet passes just below the switchback roller 26a. After that (ST14), the switchback roller 26a together with the lifting support arm 28 is lowered from the standby position (FIG. 5B) to the operating position (FIG. 5C) (step 15 in FIG. 6). At this time, when the switchback roller 26a is lowered to a predetermined height calculated from the measured height H _N-1 from the top surface of the paper surface measured at the previous time to the first height position (step 16 in FIG. 6). The lowering is stopped (ST17), the switchback roller 26a is rotated in the clockwise direction in the drawing, and the leading end of the sheet is drawn into the processing tray 29. Then, after the rear end of the sheet has passed through the paper discharge port 25x, the switchback roller 26a is reversely rotated and conveyed back to the sheet end regulating means 32 side. During the sheet conveyance process, the sheet and the switchback roller 26a are engaged with a constant pressing force regardless of the amount of sheets stacked on the processing tray, and a predetermined conveying force set in advance is applied to the sheet. .

Next, the switchback roller 26a starts to rise (ST18), and the distance (height) H _N to the first height position where the paper surface contact sensor Ss for detecting the position of the roller rotation shaft 26z is turned off is measured (FIG. Step 19 of 6). Such measurement is repeatedly performed a plurality of times (for example, three times), an average value is calculated based on the obtained plurality of measurement values, and the average value is calculated from the top surface of the sheet to the first height. Determine as H _N and store. Then, the measurement height H _N, the lowering amount for the next (N + 1) -th th sheet. Thereafter, the switchback roller 26a rises to the home position together with the lift support arm 28 and enters a standby state (ST20), and the same sheet conveyance by the switchback roller 26a is performed for the (N + 1) th and subsequent sheets. ST21).

  According to such a configuration, for example, even when a sheet is fed at a high speed or a curled portion is generated on the sheet, the sheet conveying unit 26a is once brought into contact with the uppermost surface of the stacked sheets on the processing tray 29. In addition, the detection value of the sheet stacking height can be obtained with high accuracy as a reference position for height measurement in a state where the sheet has the original stacking height by the contact action of the sheet conveying unit 26a.

Here, the maximum number of sheets to be stapled by the stapling means 31 to be described later is greatly increased (for example, 100 sheets at the maximum) compared to the conventional one (for example, 100 sheets at the maximum), and a switchback roller which is a sheet conveying means corresponding to the increase. The height of the opening formed between the upper switchback roller 26a and the lower fixed roller 26b in the pair 26 is also significantly increased (for example, 22 mm in height). Further, the distance L between the center position of the switchback roller 26 and the center position of the stapling means 31 is reduced to the smallest possible distance (for example, 130 mm) in order to reduce the size.
By reducing the distance L due to such a large opening height or downsizing, the operator may be injured by the stapling means or the like when the operator's hand or finger enters. For this reason, the switchback roller 26a in the present embodiment is configured to stop the processing operation when the switchback roller 26a rises to a predetermined height or more when the operator's hand or finger enters the opening.

  That is, the opening formed between the upper switchback roller 26a as the sheet conveying means and the lower fixed roller 26b is changed by the vertical movement of the upper switchback roller 26a. In the present embodiment, the switchback roller 26a has a preset safety reference height, that is, the above-described "first height" when the operator's hand or finger enters the opening of the sheet conveying means. A configuration is adopted in which the processing operation of the entire apparatus is urgently stopped in order to ensure the safety of the stapling means 31 when it is raised to a higher “second height”.

In particular, in the present embodiment, when predetermined processing is performed on the sheets stacked on the processing tray 29 by the end binding unit 31 as processing means, the above-described “first height” and “second height” are described. When the height detecting means (not shown) detects that the switchback roller (first roller) 26a has risen above the “third height” that is different from the “height”, the elevation control means 165 A configuration is employed in which the end binding unit (processing means) 31 is stopped. The “third height”, which is the safety reference height when the processing means 31 performs processing, that is, the emergency stop in the staple binding operation, is the safety reference height in the operation other than the staple binding operation. It is configured to be lower than a certain “second height”.

For this reason, first, the elevation that supports the switchback roller 26a as the sheet conveying means corresponding to the reference height (second height) at the high position and the reference height (third height) at the low position. A micro switch (not shown) for detecting the height position of the support arm (conveyance guide member) 28 is provided. In an operation other than the stapling operation, for example, when the switchback roller 26a rises above the safety reference height at the high position (second height) of 26 mm, the switchback roller 26a is raised. The high-position microswitch detects the processing operation based on the detection output from the high-position microswitch. This is because even if a relatively large opening is formed because the stapling operation is not performed, safety against the stapling means 31 is ensured, so that an emergency stop is not performed until the large opening is formed. It is a thing. On the other hand, at the time of stapling operation, when the switchback roller 26a rises to a safety reference height (third height) at a low position, for example, 18 mm high, a processing operation is performed by the detection action of the low position microswitch. Emergency stop.
This is because the staple binding operation is performed, so that the safety of the stapling means cannot be ensured unless the opening is made small.

  More specifically, as shown in FIG. 7, when the post-processing operation is started, first, the process of the first condition I is executed (ST70). In the first condition I, as shown in FIG. 8, the lifting support arm (conveying guide member) 28 supporting the switchback roller 26a has a safety reference height at a high position “second”. It is determined whether or not it has risen to “height” (for example, height of 26 mm) (ST81), and if it has not risen to the safety reference height at the high position (second height), the first condition I Is finished (ST82). On the other hand, when the height is higher than the safety reference height at the high position (second height), the post-processing operation is stopped urgently and a warning is issued (ST83), and the post-processing operation ends ( ST84). The control operation based on the first condition I is always executed until the control operation is switched to the control operation based on the second condition II described later.

  As described above, when the lifting support arm (conveying guide member) 28 supporting the switchback roller 26a has not risen to the safety reference height at the high position (second height), the lifting / lowering support arm 28 is moved up and down. The support arm 28 is raised toward the home position (for example, height 22 mm) until a photo sensor (not shown) detects it (ST71). Thereafter, the printed sheet (recording medium) is received on the processing tray 29 as described above (ST72), and the sheet bundle is sandwiched and conveyed by the switchback roller pair 26 (ST73). If the stapling operation is not performed on the sheet bundle (ST74), the sheet bundle on the processing tray 29 is aligned (ST75).

  On the other hand, when the stapling operation is performed on the sheet bundle on the processing tray 29 (step 74), the height detection member relating to the “third height” which is an appropriate low position (not shown) is set to a predetermined value. It is moved to a detectable position (ST76), and the process of the second condition II is executed using the height detection member at the low position (third height) (ST77). In the second condition II, as shown in FIG. 9, the elevating support arm (conveying guide member) 28 supporting the switchback roller 26a has a safety reference height (for example, a height) at a low position. 18 mm) or more is determined (ST91), and if the safety reference height is not raised to the low position (third height), the operation of the second condition II is ended ( ST92). Further, when the safety level is higher than the safety reference height at the low position (third height), the post-processing operation is urgently stopped and a warning is issued (ST93), and the post-processing operation ends ( ST94). The control operation according to the second condition II is always executed until the control operation according to the first condition I described above is switched.

  If the lifting support arm (conveying guide member) 28 supporting the switchback roller 26a is not raised to the safety reference height at the low position (third height), the sheet on the processing tray 29 is displayed. After aligning the bundle. A stapling operation is executed (ST78). In this way, the alignment process is performed on the processing tray 29 (ST77), or the sheet bundle after the stapling operation is performed after the alignment process is conveyed toward the stack tray 21 (ST79). The post-processing operation is terminated.

"Aligning mechanism"
On the processing tray 29, an aligning mechanism (aligning means) 51 for conveying the sheet to the sheet end regulating means 32 together with the switchback roller 26a is provided. As shown in FIG. 10A, the aligning means 51 is disposed immediately below the sheet discharge outlet 25x, scrapes the rear end of the sheet carried into the processing tray 29, and conveys the sheet toward the sheet end regulating means 32. The friction rotating body 52 is configured.

  The friction rotating body 52 is composed of a rotating body such as a rubber material, sponge (porous foam), other rollers, and a belt, and engages with the uppermost sheet on the tray and conveys it in a predetermined direction by the friction force. The illustrated friction rotator 52 is configured to move up and down according to the amount of sheets stacked on the processing tray 29. For this reason, a friction rotating body (roller) 52 is supported by a support on an elevating support arm 54 that is rotatably supported by an oscillation frame 53 on an apparatus frame (not shown). A driving pinion 53p is attached to the oscillating rotating shaft 53, and a stepping motor MC is connected to the driving pinion 53p. A torque limiter (not shown) is built in between the drive pinion 53p and the swing rotation shaft 53. Therefore, when the friction rotating body 52 attached to the lifting support arm 54 comes into contact with the uppermost sheet on the processing tray 29, the torque limiter idles by the reaction force, and always engages with the uppermost sheet with a constant pressure. .

  For this reason, regardless of the amount of sheets stacked on the processing tray 29, the friction rotating body 52 engages on the uppermost sheet, and the lifting support arm 54 stops at this position. Then, after the elevating support arm 54 stops on the uppermost sheet, a torque limiter (not shown) idles and applies a predetermined pressing force to the friction rotating body 52. An idle pulley is supported on the swing rotation shaft 53, and a drive motor (not shown) is connected to the pulley. The rotational force of the drive motor is transmitted from the pulley to the friction rotating body 52 by a belt or the like. The friction rotating body 52 configured as described above rotates in the counterclockwise direction in FIG. 10 at the operation position shown in FIGS. 10B and 10C and directs the sheet carried on the processing tray toward the sheet end regulating means 32. It is designed to be transported.

  The above-described lifting support arm 54 is provided with a carry-in guide 54 a on the upstream side of the friction rotating body 52 and a carry-out guide 54 b on the downstream side. The carry-in guide 54a is formed in a guide shape for guiding the sheet leading end to the friction rotating body 52, and the carry-out guide 54b is positioned between the friction rotating body 52 and the sheet end regulating means 32. The guide shape is configured to guide each.

"Import guide"
As shown in FIG. 10A, the carry-in guide 54a is integrally formed with the lifting support arm 54 so that the sheet carry-in side is high and the friction rotator side is low so as to guide the leading end of the sheet in the circumferential surface direction of the friction rotator 52. An inclined taper surface 54a1 is provided. Therefore, even if the trailing edge of the sheet fed toward the sheet edge regulating means 32 by the switchback roller 26a is curled and warped, it is guided to the friction rotating body 52 along the tapered surface 54a1. . Since this carry-in guide 54a is integrally formed with the lifting support arm 54, it is lifted upward according to the amount of sheets stacked on the processing tray. The carry-in guide 54a is formed integrally with the friction rotator 52 as described above. When the roller diameter of the rotator is reduced (for miniaturization), the sheet with the trailing edge curled is caught in the roller and jammed. Therefore, when guiding with the carry-in guide, the angular relationship between the guide surface (the taper surface described above) and the roller peripheral surface changes according to the sheet stacking amount, causing jamming. In order to solve such a problem, the friction rotating body 52 and the carry-in guide 54a are integrated so as to move up and down according to the sheet stacking amount.

"Unloading guide"
The carry-out guide 54 b includes a guide surface 54 b 1 that guides the rear end side of the sheet fed by the friction rotating body 52 from above and guides it to the sheet end regulating means 32. Similarly to the carry-in guide 54a, the carry-out guide 54b is integrally formed with the lifting support arm 54 and is configured integrally with the friction rotating body 52. Accordingly, the sheet is moved upward in accordance with the sheet stacking amount on the processing tray.

  Therefore, the carry-in guide 54a and the carry-out guide 54b are set such that the distance (L1) between the carry-in guide 54a and the uppermost sheet with respect to the uppermost sheet of the processing tray 29 is as shown in FIG. (L1> L2) is set larger than the interval (L2).

"Configuration of kicker means"
The carry-in guide 54a guides the sheet from the paper discharge port 25x to the friction rotating body 52 in cooperation with the kicker means 55 arranged on the upstream side. The kicker means 55 will be described. As described above, a step is formed between the paper discharge outlet 25x and the processing tray 29, and the trailing edge of the sheet sent from the paper discharge outlet 25x by the switchback roller 26a falls onto the processing tray 29. Therefore, a kicker means 55 is provided at the paper discharge port 25x.

  As shown in FIG. 10A, the kicker means 55 is composed of a base end swing lever 55a and a front end kick lever 55b installed on the apparatus frame by a rotating shaft 56. A drive motor 57 is connected to the rotating shaft 56 of the base end swing lever 55a by a gear. In addition, the shaft is pivotally connected to the tip of the tip kick lever 55b. As shown in FIGS. 10E and 10F, the rotary shaft 56 is swung at a predetermined rotation angle by a drive motor 57, and the shaft fulcrum 55b1 of the tip kick lever 55b is connected to the rotary shaft 56 via a gear and a belt. It is connected. Accordingly, the kicker means 55 at the broken line position (standby position) in FIG. 10 (e) rotates the base end swing lever 55a in the direction indicated by the arrow a (counterclockwise) when the drive motor 57 is rotated in the clockwise direction. . At this time, since the tip kick lever 55b is connected to the rotating shaft 56, the gear, and the belt, the tip kick lever 55b rotates in the direction indicated by the arrow b (clockwise). Accordingly, when the drive motor 57 is rotated forward (clockwise in the drawing), the kicker means 55 is moved from the broken line state to the solid line state in FIG. 10 (e). Strike 29.

  The control CPU 160, which will be described later, energizes the drive motor 57 at the timing when the trailing edge of the sheet passes the discharging roller 25 by the detection signal that the trailing edge of the sheet has passed through the discharging sensor S2 of the discharging port 25x, and the trailing edge of the sheet is set to the tray. Kick it up. The rear end of the sheet dropped by the kicker means 55 is arranged to be guided to the friction rotating body 52 by the carry-in guide 54a.

[Configuration of side alignment means]
The processing tray 29 is provided with side aligning means 34 for aligning and aligning sheets. The side aligning unit 34 employs either a center reference for aligning with respect to the center of the sheet carried into the processing tray 29 from the sheet discharge outlet 25x or a side reference for aligning with respect to the left and right side edges of the sheet. Is done. The operation will be described with reference to the perspective view shown in FIG. 4 and the operation state diagrams shown in FIGS.

  As shown in FIG. 4, the side alignment means 34 includes a left alignment plate 34L that engages with the left edge of the sheet on the processing tray 29, and a right alignment plate 34R that engages with the right edge of the sheet. The left and right alignment plates 34L and 34R are fitted and supported in guide grooves (see FIG. 4) formed in the sheet support surface 29a of the processing tray, respectively, and can be moved in the sheet width direction. As shown in FIG. 11, a pair of pulleys 35 is disposed along the guide groove on the bottom of the processing tray 29, and a belt 36 is bridged over the pulleys 35. The left and right alignment plates 34L and 34R are fixed to the belt 36. Further, shift motors MZ1 and MZ2 are connected to one of the pulleys 35.

  The left alignment plate 34L and the right alignment plate 34R, which are formed as a pair on the left and right sides in such a configuration, are moved to the left and right in the sheet width direction by driving the shift motors MZ1 and MZ2. Therefore, the left and right shift motors MZ1 and MZ2 are synchronously driven in the opposite direction by the same amount so that the sheets carried on the processing tray can be aligned with the center reference. FIG. 11A shows a state in which large size sheets are aligned, and FIG. 11B shows a state in which medium size sheets are aligned. FIG. 12C shows a state in which small-size sheets are aligned. On the other hand, the sheet bundle aligned on the processing tray with the center reference can be offset by rotating the left and right shift motors MZ1, MZ2 in the same direction by the same amount. FIG. 12D shows a case where the large size sheet is offset. In this way, offsetting a large-size sheet by a predetermined amount requires that the post-processing means 31 be moved to the side of the apparatus when the post-processing position is biased to the sheet corner (corner staple described later), and the size of the apparatus is increased. Bring. Thus, post-processing such as corner binding can be performed by offsetting the sheet bundle accumulated on the processing tray 29 by a predetermined amount. This achieves a compact and compact device.

[Linking mechanism of alignment plate and movable stopper]
The pair of left and right alignment plates 34L and 34R configured as described above are interlocked with the sheet end regulating means 32 described above as follows. The sheet end regulating means 32 includes a left movable stopper (second movable stopper member) 32C and a right movable stopper (first movable stopper member) 32B. The left and right movable stoppers 32B and 32C are arranged on the processing tray 29. Are connected to left and right slide members 38a and 38b which are fitted and supported so as to be movable in the sheet width direction.

  Therefore, the left and right movable stoppers 32B and 32C are connected to the left and right alignment plates 34L and 34R by a connection spring 37 as shown in FIG. That is, the right slide member 38a having the right movable stopper 32B is connected by the connecting spring 37a, and the left slide member 38b having the left movable stopper 32C is connected by the connecting spring 37b. The left and right alignment plates 34L and 34R reciprocate between the strokes LS1 in the sheet width direction. On the other hand, the left and right movable stoppers 32B and 32C are driven between the strokes LS2. For this reason, stop members (not shown) are arranged on the processing tray 29 side in the left and right movable stoppers 32B and 32C.

  The strokes LS1 and LS2 are set such that LS1> LS2, and the left and right movable stoppers 32B and 32C move by the same amount until they hit the stop member in conjunction with the movement of the left and right alignment plates 34L and 34R. . The movable stoppers 32B and 32C stop at this position after hitting the stop member, and the alignment plates 34L and 34R further move. At this time, the connecting springs 37a and 37b connecting the two extend (extend). Accordingly, the left and right alignment plates 34L and 34R move between strokes LS1 corresponding to the sheet size, and the movable stoppers 32B and 32C move between strokes LS2. The reason why the strokes of the left and right movable stoppers 32B and 32C are set to be short is that a sheet bundle carrying-out means 100 described later is arranged at the center of the sheet.

  As described above, when the left and right movable stoppers 32B, 32C constituting the sheet end regulating means 32 are interlocked with the side aligning means 34 and the movement strokes of the both are made different, the coupling spring 37 is used in the illustrated embodiment. . The left and right alignment plates 34L and 34R and / or the left and right movable stoppers 32B and 32C may use “sliding transmission mechanism” or “deceleration transmission mechanism”.

In the case of the “sliding transmission mechanism”, the left and right alignment plates 34L and 34R and the left and right movable stoppers 32B and 32C are connected by a sliding friction clutch, and the left and right movable stoppers 32B and 32C come into contact with the stop member, and then the clutch plate is moved. Configure to slide.
In the case of the “deceleration transmission mechanism”, the left and right alignment plates 34L and 34R and the left and right movable stoppers 32B and 32C are connected by a gear transmission mechanism, and at this time, the alignment plates 34L and 34R move by the stroke LS1. The gear ratio is set so that 32B and 32C move with the stroke LS2.

[Configuration of sheet bundle carry-out means]
The processing tray 29 is provided with a sheet bundle carrying-out means 100 for carrying out the processed sheet bundle to the downstream stack tray 21. The sheet bundle carrying-out means 100 is disposed at the bottom of the processing tray 29, protrudes above the sheet support surface 29a and engages with the sheet bundle, and mounts and supports the sheet engaging member 105. It is comprised with the carrier member 110. FIG. 13 is an explanatory view showing a perspective configuration of the sheet bundle carrying-out means 100, and FIG. 14 is an explanatory view showing a planar structure of the sheet bundle carrying-out means 100. FIG. 16 is an explanatory diagram of the drive mechanism.

  As shown in FIGS. 13 and 17, the sheet bundle carrying-out means 100 includes a sheet engaging member 105, a carrier member 110, an engaging member driving means 127, and a carrier member driving means 114. The sheet engaging member 105 includes a movable gripper 105a and a fixed gripper 105b. The carrier member 110 is mounted with the sheet engaging member 105 and is configured to reciprocate from the base end portion (post-processing position) of the processing tray 29 to the front end portion (bundle unloading position).

[Description of control configuration]
The control configuration of the above-described image forming system will be described with reference to the block diagram of FIG. The image forming system shown in FIG. 1 includes a control unit (hereinafter referred to as “main body control unit”) 150 of the image forming apparatus A and a control unit (hereinafter referred to as “post-processing control unit”) 160 of the post-processing apparatus B. The main body control unit 150 includes an image formation control unit 151, a paper feed control unit 152, and an input unit 153. Then, “image formation mode” and “post-processing mode” are set from the control panel 118 provided in the input unit 153. As described above, the image forming mode sets the number of printouts, sheet size, color / monochrome printing, enlargement / reduction printing, duplex / single-sided printing, and other image formation conditions. Then, the main body control unit 150 controls the image formation control unit 151 and the paper feed control unit 152 according to the set image forming conditions, and after the image is formed on a predetermined sheet, the sheets are sequentially carried out from the main body discharge port 3. .

  At the same time, the post-processing mode is set by input from the control panel 118. The post-processing mode is set to, for example, “print-out mode”, “staple binding finishing mode”, or the like. Therefore, the main body control unit 150 transfers the post-processing finishing mode and the number of sheets, the upper number of copies, and the binding mode (one-position binding or two or more bindings) information to the post-processing control unit 160. At the same time, the main body control unit 150 transfers a job end signal to the post-processing control unit 160 every time image formation is completed.

  The post-processing control unit 160 includes a control CPU 161 that operates the post-processing apparatus B according to a designated finishing mode, a ROM 162 that stores an operation program, and a RAM 163 that stores control data. The control CPU 161 includes a sheet conveyance control unit 164a that performs conveyance of the sheet sent to the carry-in entrance 23a, a sheet accumulation operation control unit 164b that performs sheet accumulation operation, and a binding operation control that performs sheet binding processing. A unit 164c and a sheet bundle folding operation control unit 164d that executes a sheet bundle folding operation.

  The sheet conveyance control unit 164a is connected to the control circuit for the drive motor (not shown) of the carry-in roller 23 and the paper discharge roller 25 in the first carry-in path P1 described above, and from the sheet sensor S1 disposed in the carry-in path. The detection signal is configured to be received. The sheet stacking operation control unit 164b is connected to a drive circuit of a forward / reverse rotation motor of the switchback roller 26a and a shift motor of a sheet end regulating member in order to stack sheets on the processing tray 29. Further, the binding operation control unit 164 c is connected to a drive circuit of a drive motor MD built in the end binding unit 31 of the processing tray 29 and the saddle stitching staple unit 40 of the accumulation guide 45.

  The sheet bundle folding operation control unit 164d is connected to a drive circuit of a drive motor that drives and rotates the folding rolls 46a and 46b and a drive circuit of a clutch unit. The sheet bundle folding operation control unit 164d is connected to a control circuit of shift means for controlling the movement of the conveying roller 27 of the second carry-in path P2 and the leading end stopper 43 of the stacking guide 45 to predetermined positions, and is arranged in these paths. Wired so as to receive a detection signal from the sheet sensor.

The control unit configured as described above causes the post-processing apparatus B to execute the next processing operation.
"Printout mode"
In this mode, the image forming apparatus A forms an image of a series of documents from the first page, for example, and sequentially unloads from the main body discharge port 3 face down, and the sheet sent to the first carry-in path P1 is discharged to the discharge roller 25. Led. Therefore, after the expected time that the leading edge of the sheet reaches the switchback roller 26a of the processing tray 29 based on the signal that the leading edge of the sheet is detected at the paper discharge port 25x, the sheet conveyance control unit 164a moves the switchback roller 26a from the upper standby position onto the tray. The roller is lowered and rotated in the clockwise direction in FIG. Then, the sheet that has entered the processing tray 29 is transported toward the stack tray 21 by the switchback roller 26a and is stored on the tray. In this way, the subsequent sheets are sequentially carried out to the stack tray 21 and accumulated and stored on the tray.

  Accordingly, in this printout mode, the sheet on which the image is formed by the image forming apparatus A passes through the first carry-in path P1 of the post-processing apparatus B and is accommodated in the stack tray 21, for example, n pages sequentially from page 1 in a face-down posture. It will be loaded and stored in order.

"Staple binding finish mode"
In this mode, the image forming apparatus A forms an image of a series of documents from the first page to the nth page in the same manner as in the above-described mode, carries out the document from the main body discharge port 3 in a face-down state, and enters the first carry-in path P1. The fed sheet is guided to the paper discharge roller 25. Therefore, after the expected time that the leading edge of the sheet reaches the switchback roller 26a of the processing tray 29 based on the signal that the leading edge of the sheet is detected at the paper discharge port 25x, the sheet conveyance control unit 164a moves the switchback roller 26a from the upper standby position onto the tray. Then, the switchback roller 26a is rotated clockwise in FIG. Next, the sheet conveyance control unit 164a drives the switchback roller 26a to rotate counterclockwise in FIG. 2 after the estimated time when the sheet trailing edge is carried onto the processing tray 29. Then, the sheet that has entered from the paper discharge port 25x is switched back and conveyed onto the processing tray 29. By repeating this sheet conveyance, a series of sheets are stacked on the processing tray 29 in a face-down state.

  Note that each time the sheets are stacked on the processing tray 29, the control CPU 161 operates the side aligning unit 34 to align the width direction positions of the sheets to be stacked. Next, the control CPU 161 operates the edge binding unit 31 in response to a job end signal from the image forming apparatus A to bind the trailing edge of the sheet bundle stacked on the processing tray. After this stapling operation, the control CPU 161 moves the sheet bundle carrying-out means 100. Then, the staple-bound sheet bundle is carried out and stored in the stack tray 21. As a result, a series of sheets formed by the image forming apparatus A is stapled and stored in the stack tray 21.

  As mentioned above, although the embodiment of the invention made by the present inventor has been specifically described, the present invention is not limited to the above embodiment, and it goes without saying that various modifications can be made without departing from the scope of the invention. Nor.

  For example, in each of the above-described embodiments, the present invention is applied to an apparatus that cuts a folded sheet bundle that has been subjected to the folding process. The present invention can be similarly applied to an apparatus for cutting a sheet bundle that has not been formed.

  In each of the above-described embodiments, the present invention is applied to an image forming system including a copying machine. However, an image forming system including another image forming apparatus such as a printer, or an image forming apparatus. The present invention can be similarly applied to a single case or a single sheet cutting apparatus.

  As described above, the sheet post-processing apparatus and image forming system according to the present invention can be widely applied to a wide variety of image forming apparatuses such as printers and copiers, and other apparatuses.

A Image forming apparatus 2 Image forming section B Sheet post-processing apparatus BX1 First processing section BX2 Second processing section 20 Casing (apparatus frame)
21 Stack tray (elevating tray)
22 Saddle Tray 23 Carry-in Roller 25 Paper Discharge Roller 26 Switch Back Roller 26a First Roller 26b Second Roller 27 Transport Roller 29 Processing Tray 31 Edge Binding Unit (Post-Processing Unit)
40 Saddle Stapling Unit (Saddle Stitching Unit)
44 Folding mechanism (middle folding unit)
45 Stacking Guide 46 Folding Roller Pair 47 Folding Blade 51 Aligning Means 60 Punch Unit 70 Driver 75 Clincher 85 Sheet Conveyance Path (Discharge Path)
90 Trimmer unit (sheet cutting device)
95 Support frame 150 Main body control unit 160 Post-processing control unit 201 Trimmer entrance roller pair (bundle conveying means)
202 Bundle conveying press means (pressing means, bundle conveying means)
202b Bundle press roller 202c Bundle press roller 202d, 202e Rotating arm 202f Link rod 203 Paper discharge roller pair 204 Cutting means 204 Cutting blade (cutting means)
205 Sheet retainer 207 Scrap flapper 208 Dust chute 209 Scrap box 210 Registration plate (positioning means)
210a Standing wall portion 211 Registration removal driving portion T Middle folded sheet bundle

Claims (4)

A processing tray for stacking sheets to be processed, processing means for processing the sheets stacked on the processing tray, sheet transporting means for transporting sheets to the processing tray, and controlling the processing means and the sheet transporting means Control means,
The sheet conveying means includes a first roller that is movable in the vertical direction, a second roller that is fixedly provided at a position facing the first roller, and that is adjacent to the processing tray, and the movement of the first roller. Constituted by a height detecting means for detecting the height,
When stacking sheets on the processing tray, the first roller rises to a first height, and stacks sheets between the first roller and the second roller and on the processing tray. A sheet post-processing apparatus configured to stop the operation of the control means when the height detection means detects that the first roller has risen to a second height higher than the first height. In
When a predetermined process is performed on the sheets stacked on the processing tray by the processing unit, the first roller is raised above a third height different from the first height and the second height. The sheet post-processing apparatus, wherein when the height is detected by the height detection means, the control means stops at least the processing means.   The sheet post-processing apparatus according to claim 1, wherein the third height is lower than the first height and the second height.   The sheet post-processing apparatus according to claim 1, wherein the predetermined process is a staple process.   The sheet post-processing apparatus according to claim 1, wherein the height detection unit detects a height of the first roller with a micro switch.

Images